Brother DB2-DD7100A Service manual

SERVICE MANUAL
SL-710A
DB2-DD7100A
DB2-DD7100
Please read this manual before making any adjustments.
SINGLE NEEDLE DIRECT DRIVE STRAIGHT LOCK STITCHER
WITH THREAD TRIMMER
This service manual is intended for SL-710A, DB2-DD7100A, DB2-DD7100 ; be sure to read the SL-710A, DB2DD7100A, DB2-DD7100 instruction manual before this manual.
Carefully read the “SAFETY INSTRUCTIONS” below and the whole of this manual to understand this product before you
start maintenance.
As a result of research and improvements regarding this product, some details of this manual may not be the same as
those for the product you purchased.
If you have any questions regarding this product, please contact a Brother dealer.
SAFETY INSTRUCTIONS
1. Safety indications and their meanings
This service manual and the indications and symbols that are used on the machine itself are provided in order to ensure
safe operation of this machine and to prevent accidents and injury to yourself or other people.
The meanings of these indications and symbols are given below.
Indications
DANGER
The instructions which follow this term indicate situations where failure to follow the
instructions will almost certainly result in death or severe injury.
C AU T I O N
The instructions which follow this term indicate situations where failure to follow the
instructions could cause injury when using the machine or physical damage to
equipment and surroundings.
Symbols
........................................ This symbol (
) indicates something that you should be careful of. The
picture inside the triangle indicates the nature of the caution that must be
taken.
(For example, the symbol at left means “beware of injury”.)
........................................ This symbol (
) indicates something that you must not do.
........................................ This symbol (
) indicates something that you must do. The picture
inside the circle indicates the nature of the thing that must be done.
(For example, the symbol at left means “you must make the ground
connection”.)
SL-710A
i
2. Notes on safety
DANGER
Wait at least 10 minutes after turning off the power switch and disconnecting the power cord from the wall outlet
before opening the face plate of the control box. Touching areas where high voltages are present can result in
severe injury.
CAUTION
Environmental requirements
Use the sewing machine in an area which is free
from sources of strong electrical noise such as
high-frequency welders.
Sources of strong electrical noise may cause
problems with correct operation.
Any fluctuations in the power supply voltage
should be within
10% of the rated voltage for
the machine.
Voltage fluctuations which are greater than this
may cause problems with correct operation.
The power supply capacity should be greater than
the requirements for the sewing machine’s
electrical consumption.
Insufficient power supply capacity may cause
problems with correct operation.
The relative humidity should be within the range of
45 % to 85 % during use, and no dew formation
should occur in any devices.
Excessively dry or humid environments and dew
formation may cause problems with correct
operation.
Avoid exposure to direct sunlight during use.
Exposure to direct sunlight may cause problems
with correct operation.
In the event of an electrical storm, turn off the
power and disconnect the power cord from the
wall outlet.
Lightning may cause problems with correct
operation.
The ambient temperature should be within the
range of 5 to 35 during use.
Temperatures which are lower or higher than this
may cause problems with correct operation.
Installation
Machine installation should only be carried out by
a qualified technician.
Contact your Brother dealer or a qualified electrician
for any electrical work that may need to be done.
The sewing machine weighs more than 36 kg.
The installation should be carried out by two or
more people.
Do not connect the power cord until installation is
complete, otherwise the machine may operate if
the treadle is depressed by mistake, which could
result in injury.
Be sure to connect the ground. If the ground
connection is not secure, you run a high risk of
receiving a serious electric shock, and problems
with correct operation may also occur.
When securing the cords, do not bend the cords
excessively or fasten them too hard with staples,
otherwise there is the danger that fire or electric
shocks could occur.
If using a work table which has casters, the
casters should be secured in such a way so that
they cannot move.
Use both hands to hold the machine head when
tilting it back or returning it to its original position. If
only one hand is used, the weight of the machine
head may cause your hand to slip, and your hand
may get caught.
Be sure to wear protective goggles and gloves
when handling the lubricating oil, so that no oil
gets into your eyes or onto your skin, otherwise
inflammation can result.
Furthermore, do not drink the oil under any
circumstances, as they can cause vomiting and
diarrhea.
Keep the oil out of the reach of children.
Use a lamp which is rated at 6 V AC and 20 W or
less. If a lamp with a higher rating than this is
used, it could cause the lamp wires and the
transformer to overheat and burn out, which could
result in fire.
SL-710A
ii
CAUTION
Sewing
This sewing machine should only be used by
operators who have received the necessary
training in safe use beforehand.
Attach all safety devices before using the sewing
machine. If the machine is used without these
devices attached, injury may result.
The sewing machine should not be used for any
applications other than sewing.
Do not touch any of the moving parts or press any
objects against the machine while sewing, as this
may result in personal injury or damage to the
machine.
Be sure to wear protective goggles when using the
machine.
If goggles are not worn, there is the danger that if
a needle breaks, parts of the broken needle may
enter your eyes and injury may result.
Turn off the power switch at the following times,
otherwise the machine may operate if the treadle is
depressed by mistake, which could result in injury.
When threading the needle
When replacing the bobbin and needle
When not using the machine and when leaving
the machine unattended
If using a work table which has casters, the casters should
be secured in such a way so that they cannot move.
Use both hands to hold the machine head when
tilting it back or returning it to its original position. If
only one hand is used, the weight of the machine
head may cause your hand to slip, and your hand
may get caught.
If an error occurs in machine operation, or if abnormal
noises or smells are noticed, immediately turn off the
power switch. Then contact your nearest Brother
dealer or a qualified technician.
If the machine develops a problem, contact your
nearest Brother dealer or a qualified technician.
Cleaning
Turn off the power switch before carrying out
cleaning, otherwise the machine may operate if
the treadle is depressed by mistake, which could
result in injury.
Use both hands to hold the machine head when tilting it
back or returning it to its original position. If only one hand
is used, the weight of the machine head may cause your
hand to slip, and your hand may get caught.
Be sure to wear protective goggles and gloves
when handling the lubricating oil, so that no oil
gets into your eyes or onto your skin, otherwise
inflammation can result.
Furthermore, do not drink the oil under any
circumstances, as they can cause vomiting and
diarrhea.
Keep the oil out of the reach of children.
Maintenance and inspection
Disassembly, assembly, maintenance and inspection
of the sewing machine should only be carried out by a
qualified technician.
Ask your Brother dealer or a qualified electrician to
carry out any maintenance and inspection of the
electrical system.
Turn off the power switch and disconnect the
power cord from the wall outlet at the following
times, otherwise the machine may operate if the
treadle is depressed by mistake, which could
result in injury.
When carrying out inspection, adjustment and
maintenance
When replacing consumable parts such as the
rotary hook and knife
Turn off the power switch before inserting or
removing the plug, otherwise damage to the
control box could result.
Use both hands to hold the machine head when tilting it
back or returning it to its original position. If only one hand
is used, the weight of the machine head may cause your
hand to slip, and your hand may get caught.
If the power switch needs to be left on when
carrying out some adjustment, be extremely
careful to observe all safety precautions.
Be careful not to touch your fingers or the lubrication
amount check sheet against moving parts such as
the rotary hook or the feed mechanism when
checking the amount of oil supplied to the rotary
hook, otherwise injury may result.
Use only the proper replacement parts as
specified by Brother.
If any safety devices have been removed, be
absolutely sure to re-install them to their original
positions and check that they operate correctly
before using the machine.
Any problems in machine operation which result
from unauthorized modifications to the machine
will not be covered by the warranty.
SL-710A
iii
3. Warning labels
The following warning labels appear on the sewing machine.
Please follow the instructions on the labels at all times when using the machine. If the labels have been removed or
are difficult to read, please contact your nearest Brother dealer.
1
2
Safety devices
Finger guard
Thread take-up cover, etc.
Thread take-up cover
2
Finger guard
1
0766M
4. About the ground symbol
There is a ground symbol which is shown on
the control box in the position shown in the
illustration.
If other equipment needs to be grounded,
connect the ground wire to the screw which
is next to this ground symbol.
If the ground connection is not secure, you
run a high risk of receiving a serious shock,
and problems with correct operation may
also occur.
Ground symbol
Screw
0767M
SL-710A
iv
INDEX
1. SPECIFICATIONS.................................... 1
6. ASSEMBLY.......................................................29
2. OPTIONAL PARTS .................................. 3
6-1. Stitch length dial, reverse stitching lever
and feed regulator mechanism....................29
6-2. Rotary hook shaft, thread trimmer
cam and gear...............................................31
6-3. Plunger ........................................................31
6-4. Lower shaft, lower shaft gear
and feed regulator set..................................32
6-5. Timing belt, motor and pulley ......................34
6-6. Knee lifter lever mechanism ........................36
6-7. Needle bar and thread take-up mechanism 36
6-8. Presser foot mechanism..............................39
6-9. Feed rocker shaft ........................................40
6-10.Spring ..........................................................40
6-11.Feed bar mechanism...................................41
6-12.Sub tank, wick holder and wick ...................42
6-13.Thread tension mechanism .........................43
6-14.Oil (Feed rocker shaft).................................44
6-15.Thread trimming mechanism.......................44
6-15-1. Installing the thread trimmer cam lever 44
6-15-2. Adjusting the needle and
feed mechanism timing................................45
6-15-3. Installing the movable knife and
fixed knife.....................................................46
6-15-4. Adjusting the thread trimming timing....47
6-16.Rotary hook and bobbin case
holder position bracket ................................48
6-17.Ruler plate and needle plate .......................49
6-18.Reverse actuator assembly
and presser hoot..........................................49
6-18-1. Adjusting the presser foot height.............50
6-18-2. Adjusting the thread guide height............50
6-18-3. Adjusting the tension spring
vertical position............................................50
6-18-4. Adjusting the thread tension bracket
forward/back position...................................50
6-19.Tension release wire ...................................51
6-20.Quick reverse solenoid ................................52
6-21.Bed under cover (Gear box)........................53
6-22.Oil tank ........................................................54
6-23.Tension release wire ...................................55
6-24.Ground wire .................................................55
6-25.Operation panel ...........................................55
6-26.Face plate and thread take-up cover...........56
6-27.Safety switch ...............................................57
6-28.Arm cover, rear cover and
bobbin winder tension assembly .................57
6-29.Other devices ..............................................57
6-30.Connectors ..................................................58
6-31.Lubrication ...................................................59
6-32.Bed cover and knee lifter lever ....................60
6-33.Test operation..............................................61
6-34.Adjusting the safety switch position.............62
3. NOTES ON HANDLING .......................... 4
4. MECHANICAL DESCRIPTIONS ............. 5
4-1.
4-2.
4-3.
4-4.
4-5.
Upper shaft and needle bar mechanism .......5
Lower shaft and rotary hook mechanism ......5
Feed mechanism ...........................................6
Quick reverse mechanism .............................7
Lubrication mechanism
(Thread take-up lever and rotary hook)........8
4-6. Thread trimmer mechanism ........................10
4-6-1. Thread trimmer operation..........................10
4-6-2. Upper and lower thread trimming..............12
4-7. Tension release mechanism ........................13
4-8. Thread wiper mechanism .............................14
4-9. Presser foot lifter mechanism
(-9[][], Option) (built into machine head)......14
4-10. Lower thread detector mechanism .............15
5. DISASSEMBLY ...............................................16
5-1. Bed cover and safety switch........................16
5-2. Connectors ..................................................17
5-3. Solenoid-type presser lifter
(-9[][], Option) ..............................................17
5-4. Lower thread detector
(-31[], -41[], -91[], Option) ............................17
5-5. Covers and operation panel ........................18
5-6. Tension release wire, ground wire and
thread trimmer solenoid...............................19
5-7. Wick holder and oil tube
(Thread take-up lever) .................................20
5-8. Oil tank, Bed under cover and sub tank ......20
5-9. Quick reverse solenoid ................................21
5-10. Needle, presser hoot and
reverse actuator assy ..................................22
5-11. Thread tension mechanism ........................22
5-12. Needle plate and Feed dog .......................22
5-13. Bobbin case, rotary hook and
thread trimming mechanism ........................23
5-14. Feed bar mechanism..................................23
5-15. Feed rocker shaft .......................................23
5-16. Presser foot mechanism.............................24
5-17.Knee lifter lever mechanism ........................24
5-18. Needle bar and thread take-up mechanism25
5-19. Pulley and motor ........................................25
5-20. Timing belt ..................................................26
5-21. Spring and feed regulator ...........................26
5-22. Lower shaft, lower shaft gear and
feed regulator set.........................................27
5-23. Plunger, rotary hook shaft, gear
and thread trimmer cam ..............................27
5-24. Stitch length dial .........................................28
5-25. Reverse stitching lever and feed regulator.28
SL-710A
7. ADJUSTMENTS ..............................................63
7-1.
7-2.
7-3.
7-4.
7-5.
7-6.
7-7.
Adjusting the thread tension spring .............63
Adjusting arm thread guide R......................64
Adjusting the presser foot height.................64
Adjusting of the feed dog height..................65
Adjusting the feed dog angle .......................66
Adjusting the needle bar height...................67
Adjusting the needle and
feed mechanism timing ...............................67
7-8. Adjusting the needle and rotary
hook timing ..................................................68
7-9. Quick reverse mechanism ...........................69
7-10.Matching stitch lengths for normal
feed and reverse feed..................................69
7-11.Synchronizer Adjustment ............................70
7-12.Adjusting the tension release wire...............71
7-13.Adjusting the treadle....................................72
7-14.Adjusting the rotary hook lubrication amount.......73
8. CONTROL SYSTEM ....................................75
9. REMOVING AND INSTALLING
THE CONTROL BOX ...................................76
10. CONTROL BOX AND
MOTOR RATING PLATE ...........................77
17. SPEED SETTING METHODS ............... 100
17-1.Types of speed settings............................ 100
17-2.Setting method.......................................... 100
17-3.Checking the speed settings..................... 101
18. CLEARING THE MEMORY DATA ....... 102
19. CHECKING THE MOTOR AND
POWER SUPPLY ...................................... 103
20. CHECKING THE SOLENOIDS ............. 104
21. WIRING DIAGRAMS ................................ 105
21-1.Control circuit board assembly ................. 105
21-2.Power supply circuit board assembly
(DD7100A, 710A) ..................................... 111
21-3.Power supply circuit board assembly
(DD7100) .................................................. 120
21-4.Transformer .............................................. 129
21-5.Operation panel B-40................................ 130
21-6.Operation panel B-100.............................. 133
22. TROUBLESHOOTING ............................. 136
11. CONTROL CIRCUIT BOARD ...................79
12. FUNCTION SETTING METHODS ..........81
12-1.DIP switch functions ....................................81
12-2.Parameter setting flowchart.........................82
12-3.Parameters ..................................................83
12-4.Memory switch setting flowchart .................86
12-5.Memory switches.........................................87
13. TREADLE UNIT ASSEMBLY ...................90
13-1.Types...........................................................90
13-2.Standard setting values ...............................91
13-3.Setting method for standard
depression strokes ......................................92
14. STANDING OPERATION PEDAL ...........96
14-1.Installing the foot plug..................................96
14-2.Connectors ..................................................97
15. Puller
(commercially available) ..........................98
15-1.Timing..........................................................98
15-2.Connector ....................................................98
15-3.Binding the cord...........................................98
16. AUTO BOBBIN CHANGER ......................99
16-1.Timing..........................................................99
16-2.Connector ....................................................99
16-3.Binding the cord...........................................99
SL-710A
22-1.Sewing ...................................................... 136
22-2.Error code displays ................................... 143
1. SPECIFICATIONS
1. SPECIFICATIONS
Machine head
Models
DD7100DD7100SL-710A-
30
A
Use
Sewing speed
Start backtacking and continuous backtacking
speed
End backtacking speed
Maximum stitch length
Needle bar stroke
Thread take-up stroke
Feed dog
Feed dog height
Presser Presser bar lifter
foot
Knee lifter
height
Automatic presser lifter
Presser foot pressure
Bed size
Arm pocket size
Needle (DB X 1)
Rotary hook
Motor
Control circuit
Weight
*…
1
31
Thread trimmer
Thread wiper
Quick reverse
Automatic presser lifter
Bobbin thread detector
1
For light-weight and
difficult-to-sew
220 - 4,000 rpm
40
41
90
91
Solenoid
Solenoid
Solenoid
Solenoid
3
For medium-weight
materials
220 - 5,000 rpm *
5
For heavy-weight
materials
220 - 3,500 rpm
220 - 1,800 rpm
1,800 rpm
4.2 mm
29 mm
31 mm
57.4 mm
4 row
3 row
0.8 mm
5 mm
35 mm
61 mm
3 row (Long stitch)
1.2 mm
6 mm
13 mm
10 mm
10 - 40N
40 - 79 N
57 - 98 N
476 X 178 mm
266.5 X 134.5 mm
NS # 9
# 11
# 22
For light-weight
For medium-weight
For heavy-weight
materials
materials
materials
AC servo motor (three-phase/single-phase, 4-pole, 400 W)
Microprocessor
36 kg (41 kg for sub-class-900)
When using the rotary hook RP(Lubrication-free rotary hook),set the sewing speed to 4,000 rpm or less.
SL-710A
1. SPECIFICATIONS
Operation panel
Operation panel
B-40
B-100
Part code
J80627-001
J80629-001
SL-710A
2
2.OPTIONAL PARTS
2. OPTIONAL PARTS
Part name
Presser foot lifting solenoid set A
With knee switch
Presser foot lifting solenoid set B
Without knee switch
Lower thread detector set
DD7100A, 710A
DD7100
DD7100A, 710A
DD7100
DD7100A, 710A
DD7100
Thread wiper set
Tension gauge set
Sensor ll
Part code
S80008-001
183959-001
S80009-001
183960-001
S80007-001
183955-001
183956-001
183922-101
J80755-001
Part name
Part code
Set for new synthetic fabric *
For -[][]3 models
183910-101
If changing -[][]1 models to new synthetic fabric specifications, or if using the machine with standard specifications but
with the rotary hook replaced by the rotary hook RP (lubrication-free rotary hook), please use the following parts.
S44338-901 (Rotary hook box assembly)*
S35786-001 (Cap screw)
* …When using the rotary hook RP (lubrication-free rotary hook), set the sewing speed to 4,000 rpm or less.
Table parts
Part name
Part code
Standing operation 2 pedal #6
(Two pedals +kick pedal)
J80081-040
Standing operation 3 pedal #40
(Three pedals)
J80380-040
Standing operation 3 pedal two-speed
(Three pedals)
J80630-001
Spacer set
183504-009
Caster set
183501-001
Foot plug set, NDD (for control box)
J02953-001
0772M
0773M
0527M
0528M
1144M
SL-710A
3
3. NOTES ON HANDLING
3. NOTES ON HANDLING
About the machine set-up location
• Do not set up this sewing machine near other equipment such
as televisions, radios or cordless telephones, otherwise such
equipment may be affected by electronic interference from the
sewing machine.
• The sewing machine should be plugged directly into an AC
wall outlet. Operation problems may result if extension cords
are used.
0774M
Carrying the machine
• The machine should be carried by the arm by two people as
shown in the illustration.
* Do not hold the machine by the machine pulley.
0775M
Tilting back the machine head
• While pulling the bottom rear of the bed toward you with your
left hand, push the top right of the arm body with your rigth
hand to tilt back the machine head.
* Be careful not to get your left hand caught between the
bottom of the bed and the table.
0776M
Returning the machine head to the upright position
1. Clear away any tools, etc. which may be near the table holes.
2. While holding the face plate with your left hand, gently return
the machine head to the upright position with your right hand.
0777M
SL-710A
4
4. MECHANICAL DESCRIPTIONS
4. MECHANICAL DESCRIPTIONS
The mechanisms operate in the order of the numbers given in the illustrations.
4-1. Upper shaft and needle bar mechanism
5 Needle take-up lever
3 Upper shaft
4 Thread take-up crank
2 Rotor
1 Pulley
(1)
6 Needle bar
clamp
7 Slide block
(2)
8 Needle bar
The needle bar is guided by the needle bar bush U (1) and needle bar bush D (2).
1626M
4-2. Lower shaft and rotary hook mechanism
3 Joint
4 Timing pulley U
2 Rotor
1 Pulley
5 Timing belt
8 Lower shaft gear
6 Timing pulley D
7 Lower shaft
9 Gear
10 Rotary hook shaft assy
11 Rotary hook
1627M
SL-710A
5
4. MECHANICAL DESCRIPTIONS
4-3. Feed mechanism
1628M
Vertical movement of feed bar
1 Pulley
3 F-lifting eccentric
wheel assy
4 Feed bar
2 Lower shaft
Horizontal movement of feed bar
1 Pulley
3 Level feed
eccentric wheel
4 Level feed
2 Lower shaft
connecting rod
8 Feed bar
5 Feed regulator assy
7 Feed rocker bracket arm
6 Feed
1629M
SL-710A
6
4. MECHANICAL DESCRIPTIONS
4-4. Quick reverse mechanism
1630M
2 Quick reverse solenoid
3 Solenoid lever
4 Shaft
1 Actuator
(1)
5 Handle shaft arm
6 Connecting rod
7 Stud arm
9 F-regulator connecting rod S
10 Feed regulator assy
13 Feed rocker shaft
8 Joint
12 Feed rocker arm
11 Feed rocker arm link
<Reverse feed>
<Normal feed>
13 Feed rocker shaft
12 Feed rocker arm
11 Feed rocker arm link
10 Feed regulator assy
1631M
1632M
1. When the actuator is pressed lightly, the movement is transmitted to the various parts as shown in the illustration, so
that the angle of the feed regulator assembly is reversed.
2. When the angle of the feed regulator assembly is reversed, the feed rocker arm link and feed rocker arm change from
normal feed to reverse feed.
* Operation occurs in the same way as described above even when the reverse stitching lever (1) is lowered.
SL-710A
7
4. MECHANICAL DESCRIPTIONS
4-5. Lubrication mechanism (Thread take-up lever and rotary hook)
The lubrication mechanism for this sewing machine is a dry head method, with the oil supplied from a tank.
The oil level can be checked through the oil gauge window, without needing to tilt back the machine head or operate the
sewing machine.
DD7100A, 710A
When adding the lubricating oil for the first time after unpacking the sewing machine, pour 130 ml of lubricating oil in
through oil filler hole (1). The oil gauge in the oil gauge window (2) will rise as far as the upper reference line. (Refer to
page 59 for details on the lubrication method.)
1633M
To upper shaft, thread take-up
lever, needle bar, etc.
(2)
(3)
Upper reference line
Oil gauge
(1)
(4)
Lower reference line
(5)
Used oil
(2) Oil gauge window
To rotary hook and rotary
hook shaft
(4)
Oil gauge
(6)
(6)
Plunger pump
Decrease
Increase
(5)
1635M
1634M
1.
2.
3.
*
1636M
The lubricating oil that is poured into the oil filler hole (1) is stored in the oil tank (3).
The lubricating oil in the oil tank (3) is drawn up by the plunger pump (4).
The lubricating oil in the sub tank (5) is transferred to parts such as the thread take-up lever and needle bar by wicks.
The rotary hook lubrication amount can be adjusted using the adjusting screw (6). (Refer to page 73.)
SL-710A
8
4. MECHANICAL DESCRIPTIONS
DD7100
When adding the lubricating oil for the first time after unpacking the sewing machine, pour 120 ml of lubricating oil in
through oil filler hole (1). The oil gauge in the oil gauge window (2) will rise as far as the upper reference line. (Refer to
page 59 for details on the lubrication method.)
1637M
(2)
(3)
(1)
Upper reference line
Oil gauge
(4)
Lower reference line
To upper shaft, thread take-up
lever, needle bar, etc.
To rotary hook and rotary
hook shaft
Used oil
(2) Oil gauge window
(4)
Oil gauge
(6)
(6)
Plunger pump
Decrease
1634M
Increase
1635M
1638M
1. The lubricating oil that is poured into the oil filler hole (1) is stored in the oil tank (3).
2. The lubricating oil in the oil tank (3) is drawn up by the plunger pump (4).
3. The lubricating oil that is drawn up by the plunger pump (4) is transferred to parts such as the thread take-up lever and
needle bar by oil tubes and wicks.
* The rotary hook lubrication amount can be adjusted using the adjusting screw (6). (Refer to page 73.)
SL-710A
9
4. MECHANICAL DESCRIPTIONS
4-6. Thread trimmer mechanism
4-6-1. Thread trimmer operation
The figure below shows the thread trimmer without the high-speed rotary hook.
1) When the thread trimmer signal is received
1 Solenoid plunger
2 Solenoid lever
3 Thread trimmer cam lever shaft
4 Roller
(1)
(Moves over thread trimmer cam (1))
1639M
2) Thread trimmer holder action
4 Forked shaft
3 Roller block
5 Thread trimmer lever
6 Thread trimmer
connecting rod
2 Roller
1 Thread trimmer cam
7 Thread trimmer holder
8 Movable knife
1640M
SL-710A
10
4. MECHANICAL DESCRIPTIONS
3) Thread trimming complete stop
1641M
(1) Thread trimmer lever
<1> Thread trimmer lever
4 Solenoid
plunger
<2> Forked shaft
<3> Roller block
3 Solenoid lever
<4> Roller
2 Thread trimmer lever
(3) Thread trimmer holder
(2) Thread trimmer
connecting rod
1 Spring
(4) Movable knife
4) Thread trimmer safety device
When the movable knife does not return to its original position, the mechanism operates as shown in the illustration
below to move the movable knife to a position where it will not touch the needle.
4 Forked shaft
3 Roller block
5 Thread trimmer lever
2 Return pin
7 Thread trimmer holder
6 Thread trimmer connecting rod
8 Movable knife
1642M
SL-710A
11
1 Thread trimmer cam
4. MECHANICAL DESCRIPTIONS
4-6-2. Upper and lower thread trimming
Movable knife
1643M
1644M
2.The thread trimmer signal is then relayed, and the
thread trimmer cam drives the movable knife. The
rotary hook catches the upper thread and passes it
through the inner rotary hook.
1. When the needle rises 1.8mm (2.2mm with heavyweight materials) above the down position the rotary
hook point catches the loop formed by the needle.
Movable knife Lower thread
Fixed knife
Movable knife
Upper thread
Lower thread
finger
1645M
1646M
3. The tip of the movable knife passes through the middle of the triangular loop formed underneath the needle plate
by the rotary hook to separate the upper and lower threads. At this time, the thread take-up lever moves up slightly
from its lowest position. (The angular movement of the upper shaft is approximately 330°.)
* If the timing of this operation is advanced, it will affect the separation of the upper and lower threads by the
movable knife, and it may result in thread trimming errors.
Upper thread
Lower thread
Fixed knife
Movable knife
Lower thread
finger
1647M
(As seen with fixed knife removed)
1648M
4. The upper and lower threads caught by the movable knife in 3 above are gradually spread by the knife and lower
thread finger and cut by the fixed knife tip. The thread take-up lever has now approached the top of its stroke.
When the knife is spreading the thread, the tension release relieves the upper thread tension to prevent excessive
tension and to enable the upper thread to be smoothly extended. The length of thread spread by the movable knife
determines the length of thread remaining from the needle tip and bobbin when thread trimming is complete, and
effects stitch formation at the beginning of the next sewing procedure.
SL-710A
12
4. MECHANICAL DESCRIPTIONS
4-7. Tension release mechanism
1649M
When a thread trimming
signal is input
9 Discs
8 Disc presser
5 Tension release plate
4 Tension
1 Thread trimmer
release wire
solenoid
3 Solenoid lever
6 Tension release stud
7 Pin
2 Bolt
1650M
Seen from underneath
4 Tension release wire
1 Thread trimmer
solenoid
2 Bolt
5 Tension
release plate
4 Tension
release wire
3 Solenoid lever
1652M
6 Tension release stud
When raising the presser foot using a knee lifter or knee switch
3 Tension
release plate
1 Knee lifter
connecting rod
4 Tension
release stud
Tension release
stud
Pin
Discs
Disc presser
2 Presser bar
1651M
lifter lever
1653M
SL-710A
13
4. MECHANICAL DESCRIPTIONS
4-8. Thread wiper mechanism
When a thread wiping signal is
received after the thread is trimmed
1 Thread wiper solenoid
(Spring)
2 Thread wiper rod
3 Thread wiper crank assy
4 Thread wiper
1654M
4-9. Presser foot lifter mechanism (-9[][], Option) (built into machine head)
1655M
When knee switch is pressed
9 Knee lifter connecting rod
8 Knee lifter lever
10 Presser bar
lifter lever
11 Guide bracket
7 Knee lifter
connecting rod D
12 Presser bar
13 Presser foot
6 Knee lifter lever D
5 Presser foot lifting rod
5 Presser foot lifting rod
4 Presser foot lifting plate
1 Presser foot solenoid
3 Presser foot lifting shaft
2 Presser bar lifting lever
1656M
SL-710A
14
4. MECHANICAL DESCRIPTIONS
4-10.Lower thread detector mechanism
• The lower thread detector mechanism has been designed for materials which do not allow thread jointing or re-sewing
to be carried out when the lower thread runs out.
• The lower thread is detected after the thread is trimmed, and the amount of lower thread remaining is displayed on the
operation panel.
1658M
When a thread trimming
signal is input
(Bobbin case)
Amount of lower thread
remaining (%)
Remaining amount
setting value
1 Shaft of pin
driving solenoid
4 Detect pin
3 Slider
2 Driving lever
3 Potentiolever
1657M
Detect pin
Slider
Driving lever
Shaft of pin driving solenoid
Potentiolever
1659M
SL-710A
15
5. DISASSEMBLY
5. DISASSEMBLY
DANGER
Wait at least 10 minutes after turning off the power switch and disconnecting the power cord from the wall outlet
before opening the face plate of the control box. Touching areas where high voltages are present can result in
severe injury.
CAUTION
Disassembly and assembly of the sewing
machine should only be carried out by a qualified
technician.
Turn off the power switch and disconnect the
power cord from the wall outlet before
disassembly, otherwise the machine may operate
if the treadle is depressed by mistake, which could
result in injury.
Be sure to wear protective goggles and gloves
when handling the lubricating oil, so that no oil
gets into your eyes or onto your skin, otherwise
inflammation can result.
Furthermore, do not drink the oil under any
circumstances, as they can cause vomiting and
diarrhea.
Keep the oil out of the reach of children.
Use both hands to hold the machine head when
tilting it back or returning it to its original position. If
only one hand is used, the weight of the machine
head may cause your hand to slit, and your hand
may get caught.
Any problems in machine operation which result
from unauthorized modifications to the machine
will not be covered by the warranty.
Disassemble each part in order of the numbers.
5-1. Bed cover and safety switch
1660M
3 Bed cover
1 Knee lifter lever
[-30[], 31[], 40[], 41[]]
2 Screw [DD7100A, 710A]
2 Snap pin [DD7100]
5 Screw
6 Washer
7 Safety switch
4 Band [Cut]
1661M
SL-710A
16
5. DISASSEMBLY
5-2. Connectors
1662M
1 Operating panel connector
[Machine connector]
2 Synchronizer connector
3 Lower thread detector connector
4 Machine connector
7 Pins
6 Motor connector
5 Solenoid-type presser lifter connector
1663M
5-3. Solenoid-type presser lifter (-9[][], Option)
4 Studs [2 pcs]
3 Presser lifter solenoid assy
2 Bolts [3 pcs]
5 Shoulder screw
6 Presser foot lifting rod
1 Shoulder screw
1664M
5-4. Lower thread detector (-31[], -41[], -91[], Option)
2 Lower thread detector
1 Screws [2 pcs]
1665M
17
SL-710A
5. DISASSEMBLY
5-5. Covers and operation panel
1666M
3 Screws [4 pcs]
2 Bobbin winder
tension assy
4 Arm cover
1 Set screw
[Loosen]
5 Screws [2 pcs: Loosen]
6 Cords [2 pcs]
<DD7100>
8 Rear cover
7 Screws [6 pcs]
11 Screw
12 Thread take-up cover
13 Set screws [2 pcs: Loosen]
10 Face plate
15 Panel support
brackets [2 pcs]
9 Screws [3 pcs]
14 Operation panel
1667M
SL-710A
18
5. DISASSEMBLY
5-6. Tension release wire, ground wire and thread trimmer solenoid
1668M
7 Screw [2 pcs: Loosen]
1 Screw [Loosen]
2 Set screw [Loosen]
4 Tension release wire
3 Nuts [2 pcs]
8 Screw
6 Ground wire
9 Thread trimmer solenoid
[DD7100A,710A only]
5 Screw
12 Thread trimmer cam
lever shaft (Pull out)
11 Retaining ring E
14 Washer
18 Rubber cushion
13 Cushion
17 Collar
16 Spring
15 Thread trimmer cam lever assy
10 Set screw [Loosen]
1669M
1 Screw [Loosen]
2 Screw
3 Tension release wire
[Remove from wire holder]
4 Tension release wire
[Pull out from machine head]
1671M
1670M
19
SL-710A
5. DISASSEMBLY
5-7. Wick holder and oil tube (Thread take-up lever)
4 Screw [Loosen]
5 Oil tube
1 Wick [Untie the knot]
[Remove from underneath machine head]
2 Screws [2 pcs]
3 Wick holder
1673M
1672M
5-8. Oil tank, Bed under cover and sub tank
1674M
<DD7100A, 710A>
10 Felt
2 Screw [Loosen]
9 Bed under cover
11 Screws [2 pcs]
12 Sub tank
3 Oil tubes
5 Oil tank
4 Screws [2 pcs]
-3[][] -4[][]
Lubricating oil
1 Screw
1675M
Lubricating
oil
1) Place a dish under the lubricating oil
outlet, and then remove the screw and
drain the lubricating oil.
2) Securely tighten the screw into the
lubricating oil outlet.
8 Screws
[8 pcs]
7 Knee lifter arm connecting rod
6 Shoulder screw
While holding a pan under the gear box,
loosen the eight screws.
* The oil inside the gear box will start flowing
out from the gear box when you start to
loosen the eight screws.
SL-710A
20
5. DISASSEMBLY
1676M
<DD7100>
10 Felt
2 Screw [Loosen]
9 Bed under cover
11 Oil gauge guide
3 Oil tubes
5 Oil tank
4 Screws [2 pcs]
-3[][] • -4[][]
Lubricating oil
1 Screw
1675M
Lubricating
oil
1) Place a dish under the lubricating oil
outlet, and then remove the screw and
drain the lubricating oil.
2) Securely tighten the screw into the
lubricating oil outlet.
8 Screws
[8 pcs]
7 Knee lifter arm connecting rod
6 Shoulder screw
While holding a pan under the gear box,
loosen the eight screws.
* The oil inside the gear box will start flowing
out from the gear box when you start to
loosen the eight screws.
5-9. Quick reverse solenoid
1 Screw [3 pcs]
2 Quick reverse solenoid
1677M
21
SL-710A
5. DISASSEMBLY
5-10. Needle, presser hoot and reverse actuator assy
<Presser foot with integrated
finger guard>
1678M
3 Screw
4 Finger guard
5 Presser hoot
1 Set screw
2 Needle
7 Reverse actuator assy
6 Screws [2 pcs]
1679M
5-11. Thread tension mechanism
1 Set screw [Loosen]
2 Pre-tension assy
4 Arm thread guide
3 Screw
6 Thread tension bracket assy
7 Pin
8 Tension release stud
5 Set screw [Loosen]
10 Thread guide D
9 Thread guide
1680M
5-12. Needle plate and Feed dog
1 Screws [2 pcs]
4 Screws [2 pcs]
2 Needle plate
5 Feed dog
6 Screw
7 Ruler plate
3 Slide plate
1681M
SL-710A
22
5. DISASSEMBLY
5-13. Bobbin case, rotary hook and thread trimming mechanism
1682M
9 Screw
8 Lower thread finger
7 Washer
6 Screw
2 Bobbin case holder position bracket
1 Screw
10 Fixed knife
18 Screw [Loosen]
21 Forked shaft
22 Collar
11 Spring [Remove from stud]
20 Spring [Remove]
19 Movable knife holder assy
16 Shoulder screw
15 Knife holder presser plate
14 Screws [3 pcs]
17 Movable knife
holder
3 Bobbin case
Pull the movable knife holder in the direction
of the arrow so that the two pan screws can
be seen from the needle plate side.
13 Movable knife
12 Screws [2 pcs]
4 Screws [3 pcs]
5 Rotary hook
13 Movable knife
12 Screws [2 pcs]
1683M
5-14. Feed bar mechanism
6 Set screws [2 pcs: Loosen]
5 Oil cap
7 Feed bracket assy [Separate]
1 Set screw [Loosen]
2 Feed lifting rock bracket stud
[with wick]
4 Feed lifting eccentric wheel assy
3 Set screws [2 pcs: Loosen]
1684M
5-15. Feed rocker shaft
6 Feed rocker shaft [Pull out from the left]
5 Set screw [2 pcs: Loosen-DD7100]
2 Rubber cap
5 Set screw [2 pcs: LoosenDD7100A, 710A]
3 Screw [Loosen]
4 Feed rocker arm [separate]
1 Rubber cap
7 Collar
8 Washer [Removable]
23
[Gear box]
[Removable]
1685M
SL-710A
5. DISASSEMBLY
5-16. Presser foot mechanism
1686M
1 Adjusting screw
2 Spring guide
3 Spring
4 Washer
7 Thread guide
6 Bolt
10 Presser bar [Pull upward]
8 Guide bracket
5 Screw
9 Wick
14 Set screw [Loosen]
15 Shaft [Slide to the right]
13 Spring
12 Washer
11 Retaining ring E
17 Shaft [Pull toward the outside]
1687M
19 Tension release plate
18 Washer
16 Retaining ring E
1688M
5-17. Knee lifter lever mechanism
5 Presser bar lifter lever assy
3 Spring
1689M
[Remove in the direction of the arrow]
2 Knee lifter connecting
rod D [slide]
1 Shoulder screw
4 Shoulder screw
6 Retaining ring E
<-3[][] •-4[][]>
8 Knee lifter lever D
7 Lever shaft D
1690M
SL-710A
24
5. DISASSEMBLY
5-18. Needle bar and thread take-up mechanism
1 Rubber cap
8 Rubber cap
11 Set screws [2 pcs: Loosen]
6 Set screw [Loosen]
9 Set screws [3 pcs: Loosen]
12 Thread
7 Needle bar bush U
take-up assy
10 Crank
4 Needle bar clamp
2 Screw [Loosen]
3 Needle bar
5 Slide block
1691M
5-19. Pulley and motor
1692M
3 Screws [3 pcs]
Be careful not to confuse the screws that secure
the motor and the circuit board at this time.
2 Pulley
1 Set screws
[2 pcs: Loosen]
4 Set screws
[Loosen two screws at motor side]
5 Motor [and connectors]
Note;
Do not operate the motor by itself after it has
been removed.
1693M
If the motor will not come out
1. Insert the two screws (1) that were removed from
the end of the motor into the screw holes (A), and
tighten them. This will support the motor and make it
easier to remove.
Note; Tighten the screws (1) alternately left and right
a little at a time.
2. After removing the motor (2), remove the screws (1).
(2)
(A)
(A)
(1)
1694M
25
SL-710A
5. DISASSEMBLY
5-20. Timing belt
4 Flange
[DD7100 only]
3 Fan
[DD7100 only]
2 Screws
[3 pcs: DD7100 only]
1 Timing belt
4 Timing belt
[Remove from timing pulley D]
[Remove from the arm]
1696M
Note;
For the DD7100A and 710A, the fan and
flange do not need to be removed.
1695M
5-21. Spring and feed regulator
10 Rubber cap
13 Feed regulator shaft L
14 Washer
11 Set screws [2 pcs: Loosen]
12 Feed regulator support shaft
6 Set screw [Loosen]
9 Stud arm
7 Eccentric pin
15 Feed regulator
[Only the top can be removed]
8 Set screws
[2 pcs: Loosen]
5 Spring
4 Cover stud
3 Washer
2 Spring washer
1 Bolt
Note;
After removing the spring,
reinstall the cover stud if
working on a flat surface.
1697M
SL-710A
26
5. DISASSEMBLY
5-22. Lower shaft, lower shaft gear and feed regulator set
6 Lower shaft [Pull out]
<DD7100>
1 Set screw
[2 pcs: Loosen]
4 Set screw
[4 pcs: Loosen]
8 Lower shaft gear
1699M
5 Spacer [2 pcs]
2 Set screw
[2 pcs: Loosen]
4 Set screw [2 pcs]
3 Set screw [2 pcs: Loosen]
7 Feed regulator set
1698M
5-23. Plunger, rotary hook shaft, gear and thread trimmer cam
8 Rotary hook shaft [Pull out]
10 Thread trimmer cam
9 Gear
7 Set screw [2 pcs: Loosen]
6 Set screw [2 pcs: Loosen]
3 Plunger
5 Spacers [2 pcs]
4 Set screws [2 pcs]
2 Spring
1 Cap screw
27
1700M
SL-710A
5. DISASSEMBLY
5-24. Stitch length dial
1701M
7 Spring
2 Stitch length dial
[Turn counterclockwise
all the way]
6 Positioning pin
1 Lock lever
[Unlock: DD7100A, 710A only]
3 Positioning pin
[Push with a screwdriver or similar]
5 Stitch length dial
4 Stopper
[Turn the stitch length dial counterclockwise again so that
the stopper goes past the positioning pin]
1702M
[Turn counterclockwise
and remove]
1703M
5-25. Reverse stitching lever and feed regulator
1704M
1 Spring
[Remove from groove]
9 Washer
8 Spacer
7 Screw [2 pcs]
6 Screw [with washer and collar]
5 Spring
4 Reverse stitching lever
3 Reverse lever plate
2 Screw
[With retaining ring E]
14 Set screws
[2 pcs: Loosen]
15 Feed regulator
12 Shaft
[Pull out]
11 Bolt [Loosen]
13 Solenoid lever
Tilt back the machine head and loosen the
bolt from underneath the machine head.
10 Bolt [Loosen]
1705M
SL-710A
28
6. ASSEMBLY
6. ASSEMBLY
DANGER
Wait at least 10 minutes after turning off the power switch and disconnecting the power cord from the wall outlet
before opening the face plate of the control box. Touching areas where high voltages are present can result in
severe injury.
CAUTION
Disassembly and assembly of the sewing machine
should only be carried out by a qualified
technician.
Be sure to wear protective goggles and gloves
when handling the lubricating oil, so that no oil
gets into your eyes or onto your skin, otherwise
inflammation can result.
Furthermore, do not drink the oil under any
circumstances, as they can cause vomiting and
diarrhea.
Turn off the power switch and disconnect the
power cord from the wall outlet before assembly,
otherwise the machine may operate if the treadle
is depressed by mistake, which could result in
injury.
Keep the oil out of the reach of children.
Use only the proper replacement parts as
specified by Brother.
If the power switch needs to be left on when
carrying out some adjustment, be extremely
careful to observe all safety precautions.
If any safety devices have been removed, be
absolutely sure to re-install them to their original
positions and check that they operate correctly
before using the machine.
Use both hands to hold the machine head when
tilting it back or returning it to its original position. If
only one hand is used, the weight of the machine
head may cause your hand to slit, and your hand
may get caught.
Any problems in machine operation which result
from unauthorized modifications to the machine
will not be covered by the warranty.
6-1. Stitch length dial, reverse stitching lever and
feed regulator mechanism
1706M
(3)
[2 pcs.]
Screw stop
(2)
[A]
(2)
Horizontal
1. Insert the feed regulator assembly (1) into the
mounting hole in the arm so that the screw stop is
facing to the front.
2. Check that the feed regulator (2) moves smoothly with
no play in the direction of the arrow, and then tighten
the two set screws (3).
3. Set the feed regulator (2) so that it is horizontal as
shown in figure [A], insert the spring (4) and the
positioning pin (5) into the mounting hole, and then
screw in the stitch length dial (6).
(1)
< For DD7100A, 710A >
The positioning pin (5) should be in the groove of the
lock lever (7) when screwing in the stitch length dial (6).
(4)
(5)
(6)
(5)
1707M
SL-710A
29
(7)
1708M
6. ASSEMBLY
4. Turn the stitch length dial (6) clockwise all the way.
5. Push the positioning pin (5) with a screwdriver or
similar, and then turn the stitch length dial (6)
clockwise again so that the stopper (7) passes to the
right of the positioning pin (5).
(5)
(6)
(7)
(6)
1710M
1709M
6. Set the bolt (8) so that it is facing away from you as
shown in the illustration, and then pass the shaft (11)
through the solenoid lever (9) and the handle shaft
arm (10).
(9)
(11)
(9)
(10)
(8)
(8)
1711M
1712M
[F]
(18)
(16)
(14)
(12)
(19)
(20)
(16)
(15)
(11)
(13)
(18)
(E)
[B] <DD7100A,710A>
(16)
[C] <DD7100>
(17)
(16)
(D)
(11)
(11)
(15)
1713M
7. Place the washer (12) and spacer (13) onto the shaft
(11), and then tighten the two screws (14) and the
screw (with washer and collar) (15).
8. Pass the shaft (11) through the spring (16).
<DD7100A, 710A>
Hook the end of the spring onto the inside of the screw
(15) and under surface (D) as shown in figure (B).
<DD7100>
Hook the end of the spring onto the inside of the screw
(15) and under the stopper (17) as shown in figure (C).
9. Insert the reverse stitching lever (18).
10. Set the reverse lever plate (19) so that it is facing as
shown in the illustration, and while inserting it into the
groove in the reverse stitching lever (18), place it onto
the shaft (11).
11. Tighten the screw (20).
12. Tilt back the machine head.
13. Use tweezers or similar to hook the longer end of the
spring (16) into the second groove behind the reverse
stitching lever (18) from underneath as shown in figure
[F].
(15)
1714M
SL-710A
30
6. ASSEMBLY
6-2. Rotary hook shaft, thread trimmer cam and gear
1. Insert the rotary hook shaft (1) into the arm so that the
screw stops are at the right, and then place the thread
trimmer cam (2) onto the rotary hook shaft (1) so that it
(2)
faces as shown in the illustration.
2. Push the rotary hook shaft (1) all the way to the right,
and then install the gear (3).
3. Insert the spacers (4) into the holes in the thread
trimmer cam (2), and then tighten the set screws (5)
(two places).
4. Push the rotary hook shaft (1) 16.25 mm to the left of
the edge of the bush (6), and then tighten the two set
screws (7) and the two set screws (8).
* Align the screw stops of the rotary hook shaft (1)
with the set screw above the set screws (7) and (8).
* Check that the rotary hook shaft (1) turns smoothly
with no play in the axial (left-right) direction.
(7)
(1)
(3)
(8)
(5)
(4)
Screw stops
(1)
16.25mm
(1)
(6)
1715M
6-3. Plunger
1. Insert the plunger (1) into the mounting hole as far as it
will go.
2. Tighten the cap screw (3) that is attached to the spring
(2).
(2)
(1)
(3)
1716M
SL-710A
31
6. ASSEMBLY
6-4. Lower shaft, lower shaft gear and feed regulator set
1. Hold the lower shaft (1) so that it faces as shown in the
illustration, insert it into the arm, and pass it trough the
lower shaft gear (2) and the level feed eccentric wheel
(3) of the feed regulator assembly inside the gear box.
2. Insert the lower shaft (1) into timing pulley D (4) until it
is almost to the edge of timing pulley D (4).
3. Set so that the set screw (6) above the gear (5) and
the set screw (7) below the lower shaft gear (2) are
facing forward, and then align the blade of the gear (5)
with the blade of the lower shaft gear (2). In this
condition, align the screw stops on the lower shaft (1),
and then tighten the lower set screws (7).
4. Tighten the upper set screws (7).
5. Tighten the two set screws (8).
(At this time, align the screw stops of the lower shaft
(1) with the lower set screws (8).)
6. For the DD7100A and 710A, insert the two spacers (9)
into the screw holes in timing pulley D (4).
7. While pushing the lower shaft (1) in the direction of
timing pulley D (4), tighten the two set screws (10)
[four set screws (10) for the DD7100].
* Check that the lower shaft (1) turns smoothly with
no play in the axial (left-right) direction.
<DD7100>
(10)
(3)
(2)
(4)
(1)
(8)
(10)
Screw stops
(9)
(5)
(6)
Align
(1)
(7)
(2)
1717M
8. Insert the stud arm (11) into the arm, and then place it
straight into the joint (12).
(12)
(11)
1718M
SL-710A
32
6. ASSEMBLY
1719M
(13)
(15)
9. Push back the feed regulator (13) as shown in the
illustration, set so that the lower set screw (14) is
facing toward the front, align it with the screw stop of
the stud arm (11) and then tighten the set screw (14).
* Tighten the set screw (14) so that the stud arm (11)
and joint (12) turn smoothly with no play.
10. Tighten the upper set screw (15).
Screw stops
(11)
(12)
(14)
1720M
Screw stops
(18)
(19)
(17)
(16)
11. Insert the feed regulator support shaft (16) into the
gear box (17) as far as the inside edge and so that the
screw stop is facing toward the front.
12. Insert feed regulator shaft L (18) into the gear box (17)
so that it protrudes about 2--3 mm from the inside
edge and so that the screw stop is facing toward the
front, and then install the washer (19).
2 - 3mm
Screw stops
1721M
13. Push back the feed regulator (13) so that it goes into
the gear box (17), and then insert feed regulator shaft
L (18) and the feed regulator support shaft (16) into
the holes in the feed regulator (13).
14. Push feed regulator shaft L (18) further in until the feed
regulator (13) moves easily, and then tighten the set
screws (20) and (21).
(20)
(18)
(21)
(16)
(13)
(17)
1722M
SL-710A
33
6. ASSEMBLY
15. Align the lower set screw (22) and the set screw (7),
then align the lower set screw (22) with the screw stop
of the lower shaft (1) and tighten the set screw (22). At
this time, make sure that the movement of the feed
regulator (13) does not become stiffer.
16. Tighten the upper set screw (22).
17. Insert the rubber cap (23) into the left side of the gear
box.
(23)
(13)
(1)
(7)
(22)
1723M
6-5. Timing belt, motor and pulley
(2)
1. Insert the timing belt (1) through the motor mounting
hole, and place it onto timing pulley U (2).
2. Install the flange (3) and the fan (4) to timing pulley U
(2) with the three screws (5).
<For DD7100A, 710A>
This step is not required.
(3)
(4)
(5)
(1)
1724M
3. First pass the connector (7) of the motor (6) into the
arm, and then insert the motor (6) into the arm as far
as it will go.
4. Align the screw holes (8) in the arm with the screw
holes (9) in the motor, and then secure the motor by
tightening the three screws (10).
* Be careful not to confuse screw holes (9) and (11).
(8)
(6)
(9)
(11)
(10)
(7)
(9)
(8)
1725M
SL-710A
34
6. ASSEMBLY
(13)
5. Tighten the two motor-side screws (12) of the joint.
* At this time, align the screw stop of the rotor (13)
with the upper set screw (12).
Screw stops
(12)
1726M
Screw stops
Turning
direction
(15)
6. Set the rotor (13) so that the screw stop is facing
upward, and then install the pulley (14).
7. Secure the pulley (14) to the rotor (13) with the two set
screws (15)
* At this time, the screw stop of the rotor (13) should
be aligned with the set screw (15) that is at the rear
relative to the turning direction of the pulley (14).
(13)
(14)
1727M
8. Tilt back the machine head.
9. Check that the timing belt (1) is correctly attached to
timing pulley U (2) (refer to 1. on page 34), and then
set the timing belt (1) onto timing pulley D (16).
* While pushing the timing belt (1) in the direction of
the arrow, turn the pulley (14) to set the timing belt
(1) onto timing pulley D (16).
(16)
(1)
1728M
SL-710A
35
6. ASSEMBLY
6-6. Knee lifter lever mechanism
1. Move the knee lifter connecting rod D (1) as far to the
left as possible, and then insert knee lifter lever D (2)
into the arm bed.
2. Insert lever shaft D (3) into knee lifter lever D (2) from
underneath, and then attach retaining ring E (4).
(1)
(4)
<-3[][],-4[][]>
(2)
(3)
1729M
3. Insert presser bar lifter lever assembly (5) from the
side of the machine head, and then install the knee
lifter lever (7) to the arm bed with the shoulder screw
(6) as shown in the illustration.
4. Install knee lifter connecting rod D (1) to the knee lifter
lever (7) with the shoulder screw (8).
(5)
(7)
(1)
(6)
(8)
1730M
5. Install the spring (9) to the shoulder screw (6) so that it
faces as shown in the illustration.
6. Hook the bent end of the spring (9) onto the knee lifter
lever (7).
(7)
(9)
(6)
(9)
1731M
1732M
6-7. Needle bar and thread take-up mechanism
1. Insert the thread take-up support shaft (1) into the
machine head as shown in the illustration.
2. Insert the crank (2) into the thread take-up assembly
(3), and then insert it into the upper shaft assembly (4)
as far as it will go.
(1)
(2)
(3)
(4)
1733M
SL-710A
36
6. ASSEMBLY
1734M
(5)
(6)
3. Set the thread take-up crank (5) so that line (A) is at a
right angle to line (B) on the crank (2), and then while
pushing the crank (2), tighten the set screw (6).
(At this time, align the screw stop of the crank (2) with
the set screw (6) when tightening it.)
(2)
(A)
(5)
Approx. 90°
(B)
(2)
1735M
4. Turn the pulley to rotate the thread take-up crank (5),
and then tighten the two set screws (6).
5. Turn the pulley back and forth two or three times by
about 90°. (The upper shaft will turn and the thread
take-up assembly (3) will move into position.)
After doing this, provisionally tighten the set screw (7)
on the face plate.
(3)
(7)
(6)
(5)
1736M
(8)
Positioning notch
(7)
6. Gently move the thread take-up lever (8) to the left and
right and check that there is a small amount of
sideways play in the thread take-up lever (8).
7. Set the thread take-up support shaft (1) so that the
positioning notch is vertical, and then tighten the two
set screws (7).
(1)
1737M
SL-710A
37
6. ASSEMBLY
8. Insert the needle bar (9) into the arm from above.
9. Tap needle bar bush U (10) into the arm so that the
hole (C) is facing toward the pulley.
* Tap in needle bar bush U (10) while checking that
the needle bar (9) can move up and down
smoothly.
(This is to check that needle bar bush U (10) is
being tapped in straight downward.)
* Tap in needle bar bush U (10) until its top is about
flush with the top of the arm.
10. Pull the needle bar (9) out from the bottom of the arm.
(C)
(10)
(9)
1738M
11. Tighten the set screw (11) to secure needle bar bush
U (10).
12. Insert the slide block (12) into the groove in the arm so
that the bevelled side is facing inward.
13. Insert the needle bar clamp (13) into the crank rod (14)
and the slide block (12).
(11)
(10)
(14)
(12)
(13)
1739M
14. Insert the needle bar (9) into the arm from above.
15. Set the needle bar (9) so that the screw hole (D) is
facing toward the pulley.
16. Turn the pulley to set the needle bar (9) to its lowest
position, and then align the reference line (E) on the
needle bar (9) with the bottom edge of needle bar
bush D (15) in accordance with the type of needle to
be used.
17. Tighten the screw (16) of the needle bar clamp (13).
18. Insert the rubber caps (17) and (18).
(17)
(18)
(15)
(9)
(9)
(E)
DB X 1
DP X 5
DA X 1
(16)
(13)
(15)
(D)
0924M
1740M
SL-710A
38
6. ASSEMBLY
6-8. Presser foot mechanism
1. Insert the shaft (1) into the arm.
2. Place the tension release plate (2) and the washer (3)
onto the shaft (1).
3. Place the presser bar lifter lever (4) onto the shaft (1).
(1)
(2)
(3)
(4)
1741M
4. Push the shaft (1) to the right, and then install retaining
ring E (5) to the left-side groove.
5. Move the shaft (1) to the left, and then tighten the set
screw (6) on the arm.
6. Place the spring (7) onto the shaft (1), and then attach
it to the tension release plate (2) and to the pin of the
arm.
7. Place the washer (8) onto the shaft (1), and then install
retaining ring E (5) to the right-side groove.
(2)
(1)
(6)
(7)
(8)
(9)
(5)
(7)
1742M
8. Insert the presser bar (10) through the top of the arm,
and insert it into the bush (11).
9. Attach the wick (12) to the presser bar (10).
10. Install the guide bracket (13) to the arm and to the
presser bar (10).
11. Install the thread guide (14) to the guide bracket (13),
and provisionally tighten it with the bolt (15) and the
screw (16).
12. Place the washer (17) on top of the presser bar (10),
and then insert the spring (18) and the spring guide
(19) through the top of the arm.
13. Install the adjusting screw (20) to the top of the arm.
(20)
(19)
(18)
(17)
(14)
(15)
(10)
(13)
(16)
(11)
(12)
1743M
SL-710A
39
6. ASSEMBLY
6-9. Feed rocker shaft
1744M
(4)
(3)
(A)
(2)
(1)
(B)
(1)
<DD7100A>
<710A> (5)
<DD7100> (5)
1. Place the washer (2) onto the feed rocker shaft (1),
and then insert the feed rocker shaft (1) into the arm.
* Insert the feed rocker shaft (1) so that the screw
stop (A) of the feed rocker shaft (1) is facing upward
and the oil tube hole (B) is facing downward.
2. When the feed rocker shaft (1) is in the position shown
in the illustration, place the collar (3) onto it, and then
push the feed rocker shaft (1) in further.
* Tap a wedge or similar into the feed rocker arm (4)
so that the feed rocker shaft (1) can pass through.
3. Align the screw stop (A) on the feed rocker shaft (1)
with the rear set screw (5) relative to the pulley turning
direction, and then secure the collar (3) by tightening
the two set screws (5).
* Check that the feed rocker shaft (1) moves
smoothly with no play.
(3)
1745M
(6)
(4)
4. Remove the wedge, and then tighten the screw (6) of
the feed rocker arm (4).
* Check that the feed regulator (7) moves easily.
5. Insert the rubber cap (8) into the hole in the right side
of the gear box.
(8)
(7)
1746M
6-10. Spring
1. Insert the eccentric pin (1) into the connecting rod (2)
and the stud arm (3) so that the mark is facing in the
opposite direction to the motor (toward the bottom).
2. Tighten the set screw (4).
3. Loosen the bolt (5), and then remove the cover stud
(6).
4. Install the spring (7) to the stud arm (3) and stud (9) so
that it faces as shown in the illustration.
5. Install the cover stud (6) with the bolt (5).
(4)
(2)
(1)
Mark
(7)
(3)
(5)
(9)
(6)
1747M
SL-710A
40
6. ASSEMBLY
6-11. Feed bar mechanism
1. Install the feed dog (1) to the feed bracket assembly
(2) with the two screws (3).
(3)
(1)
(2)
1748M
(14)
(4)
1749M
(6)
(5)
(2)
(1)
2. Place the feed bracket assembly (2) onto the feed
rocker shaft (4).
3. Insert the wick (5) into the hole in the feed rocker shaft
(4), and then insert the oil cap (6).
(8)
(13)
(10)
[A]
(8)
(10)
[B]
(12)
(9)
(6)
(7)
4. Provisionally install the needle plate (7) in order to
position the feed bracket assembly (2).
1750M
(1)
(7)
Clearance Clearance
1751M
Clearance
Movement range
Clearance
1752M
5. Move the feed bracket assembly (2) to the left and
right until the left and right clearances between the
feed dog (1) and the needle plate (7) are the same.
[Feed dog left/right adjustment]
6. Place the feed lifting eccentric wheel assembly (8)
onto the lower shaft (9).
7. Place the end of the feed bracket assembly (2) into the
fork in the feed lifting eccentric wheel assembly (8),
and then insert the feed lifting rock bracket stud (10).
8. Align the O mark of the feed lifting rock bracket stud
(10) with the reference line on the feed lifting eccentric
wheel assembly (8), and then tighten the set screw
(11). (Figure (A))
9. Align the O mark of the feed lifting eccentric wheel (12)
with the reference line on the lower shaft (9), and then
tighten the two set screws (13). (Figure (B))
10. Adjust the forward/back position of the feed dog (1).
1) Turn the stitch length dial to the maximum setting.
2) Turn the pulley to rotate the feed bracket assembly
(2) in order to adjust so that the clearance between
the movement range of the feed dog (1) and the
needle plate (7) is equal at the front and the back.
3) Tighten the two screws (14).
SL-710A
41
6. ASSEMBLY
6-12.Sub tank, wick holder and wick
<DD7100A, 710A>
1. Install the sub tank (1) to the arm bed with the two
screws with washer (2).
* Be careful not to bend the oil gauge (3) at this time.
2. Insert all of the oil tubes (4) containing the wicks
through the hole in the arm bed.
(Continue to step 3.)
<DD7100A, 710A>
(4)
(3)
(2)
(1)
1753M
<DD7100>
1. Insert the oil gauge guide (1) into the mounting hole in
the arm bed so that it faces as shown in the
illustration.
* Be careful not to bend the oil gauge (3) at this time.
2. Insert all of the oil tubes (4) containing the wicks
through the hole in the arm bed.
<DD7100>
(4)
(1)
(3)
1754M
3. Route the oil tube (4) as shown in the illustration.
(4)
1755M
1755M
Piano wire
4. Use piano wire or similar to pass the wick in the oil
tube (4) through the thread take-up support shaft (5)
5. Use your finger to check that the end of the oil tube (4)
is inserted into the hole in the thread take-up support
shaft (5).
6. Secure the oil tube (4) with the cord holder (6), and
tighten the screw (7) from outside the arm.
(7)
(4)
(6)
(5)
1756M
SL-710A
42
6. ASSEMBLY
(5)
7. Install the wick holder (8) to the arm with the two
screws (9).
8. Tie together the wick that is coming out from the wick
holder (8) and the wick that is coming out from the
thread take-up support shaft (5).
9. Lift the felt support (10) up slightly.
10. Pull the wick (11) and insert the end under the felt
(12).
11. Run the wick (13) along the inside of the arm and
insert the end under the felt (12).
12. Clamp the felt (12) with the felt support (10).
(9)
(8)
(11)
(12)
(13)
(10)
1757M
6-13. Thread tension mechanism
1. Insert the pre-tension assembly (1) into the arm so
that it faces as shown in the illustration, and then
tighten the set screw (2).
2. Insert the tension release stud (3) into the mounting
hole.
3. Insert the pin (5) into the thread tension bracket
assembly (4), then insert it into the mounting hole and
tighten the set screw (6).
4. Install the arm thread guide (7) with the screw (8).
* Tighten the screw (8) so that it comes to about the
center of the arm thread guide (7).
5. Install thread guide D (9) to the groove in needle bar
bush D (10) so that the part that catches the thread
faces toward the front.
6. Install the thread guide (11) to the needle bar, and then
align the needle set screw hole (A) with the needle bar
hole.
(2)
(1)
(7)
(8) (7)
(8)
(4)
(5)
(3)
(6)
(9)
(10)
(11)
(11)
(A)
1758M
SL-710A
43
6. ASSEMBLY
6-14. Oil (Feed rocker shaft)
(1)
(DD7100A,710A)
(4)
1. Secure the end of the wick in the oil tube (1) using a
clip (2) or similar as shown in the illustration. (This is to
prevent the wick from being pulled into the oil tube.)
2. Pass the oil tube (1) behind the rotary hook shaft (3),
and insert oil cap (4) into the mounting hole in the feed
rocker shaft (5).
3. Secure the oil tube (1) with the cord holder (6) and
tighten the screw (7).
(2)
(DD7100)
(5)
(7)
(4)
(6)
(1)
(3)
1759M
6-15. Thread trimming mechanism
6-15-1. Installing the thread trimmer cam lever
(3)
(2)
(1)
(4)
Slide block
1. Place the collar (2) onto the forked shaft (1), and then
insert it into the bush (3).
2. Insert the thread trimmer cam lever shaft (4) into the
bed so that the groove is at the right.
3. Install the rubber cushion (5), collar (6) and spring (7)
to the thread trimmer cam lever shaft (4).
4. With the slide block of the thread trimmer cam lever
(8) set into the forked shaft (1), insert the thread
trimmer cam lever shaft (4) into the thread trimmer
cam lever (8).
(8)
(5)
(6)
(7)
1760M
5. Push the thread trimmer cam lever (8) to the left, and
then place the washer (9) and cushion (10) onto the
thread trimmer cam lever shaft (4). (Figure (A))
6. Push the thread trimmer cam lever shaft (4) to the right
so that the groove can be seen, and then install
retaining ring E (11). (Figure (B))
7. Push the thread trimmer cam lever (8) back to the right,
and then tighten the set screw (12).
(8)
[A]
(10)
(12)
(4)
(9)
[B]
(8)
(4)
(11)
1761M
SL-710A
44
6. ASSEMBLY
(13)
8. Place the spring (13) onto the bush (14) so that it
faces as shown in the illustration.
9. Place the thread trimmer lever (15) onto the bush (14).
* It will be easier to do this if you insert a screwdriver
or similar into the gap.
10. Hook the spring (13) onto the thread trimmer lever (15)
as shown in the illustration.
11. Place the movable knife holder (16) and the knife
holder presser plate (17) onto the pump bush (18),
and then tighten the three pan screws (19).
12. Connect the thread trimmer lever (15) and the thread
trimmer connecting rod (20) by tightening the shoulder
screw (21).
(14)
(15)
(21)
(20)
(19)(17)
(18)
(16)
(13)
(15)
1762M
13. With the solenoid lever (22) pushed all the way to the
right, install the thread trimmer solenoid (23) with the
three screws (24).
<For DD7100A, 710A>
At this time, install the stopper bracket (25) with two of
the screws (24) also.
(24)
(23)
(22)
*
Push the solenoid lever (22) to the left and check that
the solenoid lever (22) can move sideways by 5 - 6
mm.
(24)
(25)
[DD7100A,710A only]
1763M
6-15-2. Adjusting the needle and feed mechanism timing
Adjust so that the needle (3) is positioned as described
below (depending on the sub-class) when the feed dog
(1) drops from its highest position until it is level with the
top of the needle plate (2).
For sub-classes -[][]1 and -[][]3
The needle (3) should move down from its highest
position until the tip of the needle (3) is approximately 1
mm below the top of the needle plate (2).
For sub-class -[][]5
The needle (3) should move down from its highest
position until the tip of the needle (3) is approximately 3
mm above the top of the needle plate (2).
<-[][]1,-[][]3>
(3)
(2)
Approx. 1 mm
(1)
<-[][]5>
(3)
Approx. 3 mm
(2)
(1)
1764M
SL-710A
45
6. ASSEMBLY
1765M
1766M
Timing
pulley D
(5)
1. Install the needle (3) to the needle bar with the screw
(4).
2. Tilt back the machine head.
3. Loosen the two set screws (5) [four set screws for the
DD7100].
(4)
(3)
4. Turn the feed lifting eccentric wheel (6) toward you
so that the feed dog (1) moves down from its highest
position until it is level with the top of the needle plate
(2).
5. With the feed dog (1) secured in place, turn the pulley
toward you to adjust the position of the needle (3) in
accordance with the sub-class when the needle is
moving down from its highest position.
6. Tighten the two set screws (5) [four set screws for the
DD7100].
(1)
(6)
(2)
1767M
6-15-3. Installing the movable knife and fixed knife
1. Remove the needle plate and the needle.
2. Install the movable knife (1) to the movable knife
holder (3) with the two pan screws (2).
(1)
(3)
(2)
1768M
3. Tilt back the machine head.
4. Install the fixed knife (4) to the bed with the pan screw
(5).
5. Install the lower thread finger (6) to the bed with the
washer (7) and screw (8).
(5)
(4)
(6)
(8)
(7)
1769M
SL-710A
46
6. ASSEMBLY
6-15-4. Adjusting the thread trimming timing
Needle bar lowest position
Raised 5 mm
Reference line (a)
Reference line (b)
DA X 1
DA X 1
DB X 1
DP X 5
Remove the fed dog.
Thread trimmer cam position adjustment
1. Turn the pulley to raise the needle bar 5 mm from its
lowest position (reference line (a) position) so that
reference line (b) is aligned with the bottom of the
needle bar bush.
DB X 1
DP X 5
1770M
(1)
(4)
(C)
Cam rotating direction
(5)
[A]
(3)
(2)
[B]
0.5 mm
0.6 - 0.8 mm
(4)
(2)
(2)
(4)
1771M
(4)
1772M
(3)
(2)
1mm
1773M
(6)
(6)
1mm
(5)
(5)
(10)
(6)
(5)
(10)
2. From the above position, push the thread trimmer
solenoid (1) with a finger in the direction of the arrow.
At this time, adjust the position of the thread trimmer
cam (2) so that the roller shaft (4) of the thread trimmer
cam lever assembly (3) touches the hollow (c) in the
thread trimmer cam (2), and so that the clearance
between the surface of the thread trimmer cam (2) and
the roller shaft (4) is 0.6--0.8 mm. Then tighten the set
screw (5). (Figure (A))
3. Check that the clearance between the surface of the
thread trimmer cam (2) and the roller shaft (4) is 0.5
mm when the roller shaft (4) returns to the right.
(Figure (B))
* Tighten the set screw (5) at a torque of
approximately 4 N.m.
Movable knife and fixed knife position adjustment
1. Turn the pulley and push the thread trimmer solenoid
(1) with a finger.
2. While doing this, turn the pulley again until the roller
shaft (4) of the thread trimmer cam lever assembly (3)
is sitting on top of the thread trimmer cam (2). In this
position, move the thread trimmer lever (7) to adjust so
that the amount of overlap between the tip of the fixed
knife (5) and the edge of the movable knife (6) is 1 mm.
Then tighten the screw (8).
* At this time, adjust so that the meshing amount is 1
mm, using the alignment of the marks on the thread
trimmer holder and the bush as a guide.
* Tighten the screw (8) so that there is no play in the
forked shaft (9).
* The lower thread finger (10) must be below the
movable knife (6).
(7)
(8)
(9)
Marks
1774M
SL-710A
47
6. ASSEMBLY
6-16. Rotary hook and bobbin case holder position bracket
1. Remove the feed dog.
2. Tilt back the machine head.
3. Place the high-speed rotary hook (2) onto the rotary
hook shaft (1), and provisionally secure it with the
three set screws (3).
* When installing the high-speed rotary hook (2),
check that it does not touch the lower thread finger
(4).
4. Install the bobbin case holder position bracket (5) with
the screw (6).
At this time, align the notch in the high-speed rotary
hook (2) with the projection of the bobbin case holder
position bracket (5).
* Check that there is just enough clearance between
the bobbin case holder position bracket (5) and the
high-speed rotary hook (2) for the thread being
used to pass comfortably in between.
(4)
(6)
(5)
(2)
(5)
(1)
(2)
(3)
1775M
1776M
Needle bar lowest position
Raised 1.8mm (2.2mm)
(7)
Reference line (a)
DA X 1
Reference line (b)
DB X 1
DA X 1
DP X 5
DB X 1
DP X 5
(9)
(8)
0 - 0.5 mm
5. Adjust the needle and high-speed rotary hook (2)
timing.
1) Install the needle.
2) Turn the pulley raise the needle bar 1.8 mm (or 2.2
mm for sub-class -[][]5) from its lowest position
(reference line (a) position) so that reference line
(b) is aligned with the bottom of the needle bar
bush (7).
3) Loosen the three set screws (3), and then adjust
the position of the high-speed rotary hook (2) at the
condition described in step 2) above.
• Align the rotary hook tip (8) with the center of
the needle (9).
(At this time, the clearance between the top
edge of the needle hole and the rotary hook tip
(8) should be 0 - 0.5 mm.)
• Adjust the clearance between the rotary hook
tip (8) and the needle (9) to 0 - 0.5 mm.
4) Tighten the three set screws (3).
0929M
(9)
0 - 0.05 mm
0 - 0.05 mm
(8)
(3)
1078M
SL-710A
48
6. ASSEMBLY
6-17. Ruler plate and needle plate
(5)
(7)
(6)
(3)
(2)
(1)
(8)
(4)
1777M
1. Remove the needle for safety while working.
2. Install the ruler plate (1) to the bed with the screw (2).
3. Install the feed dog (3) to the feed bar (4) with the two
screws (5).
4. Install the needle plate (6) to the bed with the two pan
screws (7).
5. Install the feed dog (3) so that the clearances between
the left and right sides of the feed dog (3) and the
needle plate (6) are the same.
6. Tilt back the machine head and install the slide plate
(8).
(3)
(6)
Clearance
Clearance
1751M
6-18. Reverse actuator assembly and presser hoot
(5)
1. Install the reverse actuator (1) to the arm with the two
screws (2).
2. Install the presser foot (3) and finger guard (4) to the
presser bar with the screw (5).
(4) (3)
(1)
[A]
(3)
(2)
1779M
1778M
3. Pass the cord (6) of the reverse actuator (1) under the
arm as shown in the illustration.
<DD7100A, 710A>
(6)
<DD7100>
1780M
(6)
SL-710A
49
6. ASSEMBLY
6-18-1. Adjusting the presser foot height
The standard height for the presser foot (1) is 6 mm when
the presser foot (1) is raised by the presser bar lifter (2).
1. Raise the presser foot (1) using the presser bar lifter
(2).
2. Move the presser bar (3) up and down until the
presser foot (1) is 6 mm above the top of the needle
plate.
In addition, adjust so that the groove of the presser
foot (1) is parallel to the groove of the needle plate.
3. Tighten the bolt (4).
(4)
(1)
(2)
(3)
(1)
Parallel
6 mm
1781M
1782M
6-18-2. Adjusting the thread guide height
The standard height for the thread guide (5) is 121 mm
above the top of the bed when the presser foot (1) is
lowered.
1. Lower the presser foot (1).
2. Loosen the screw (6).
3. Adjust the position of the thread guide (5) so that it is
121 mm above the top of the bed, and then tighten the
screw (6).
(6)
(5)
(2)
121 mm
(1)
1783M
6-18-3. Adjusting the tension
spring vertical position
(7)
< For sub-classes -[][]1 and -[][]3>
6 - 8 mm
< For sub-class -[][]5>
(9)
4 - 6mm
(5)
(8)
0916M
6-18-4. Adjusting the thread tension
bracket forward/back position
(10)
The correct forward/back position of the thread tension
bracket (9) is when the tension discs (10) start to open
when the presser foot is 4 mm above the needle plate.
1. Loosen the set screw (8).
2. Move the thread tension bracket (9) forward and back
to adjust so that the tension discs (10) start to open
when the presser foot rises to 4 mm above the needle
plate.
3. Tighten the set screw (8).
* Check the vertical position of the tension spring (7)
when tightening the set screw (8).
(11)
(9)
4 mm
The standard position for the tension spring (7) is 6 - 8
mm (4 - 6 mm for sub-class -[][]5) above the top of the
thread guide (5) when the presser foot is lowered.
1. Lower the presser foot.
2. Loosen the set screw (8).
3. Turn the thread tension bracket (9) to adjust the
position of the tension spring (7).
4. Tighten the set screw (8).
* Check the forward/back position of the thread tension
bracket (9) when tightening the set screw (8).
1784M
SL-710A
50
6. ASSEMBLY
6-19. Tension release wire
1785M
(1)
1. Insert the terminal (2) end of the tension release wire
(1) through the top of the arm, and attach it to the
tension release plate (3).
(3)
(2)
2. Pass the other end of the tension release wire (1)
through the arm as shown in the illustration.
(1)
1786M
3. Secure the tension release wire (1) with the wire
holder (4) as shown in the illustration.
(1)
(4)
(4)
(1)
Approx. 10 mm
1787M
SL-710A
51
6. ASSEMBLY
6-20. Quick reverse solenoid
1. Pass the cord (2) of the quick reverse solenoid (1)
under the bed.
2. Install the quick reverse solenoid (1) to the arm with
the three screws (4) so that the plunger pin (3) fits into
the groove (A) in the solenoid lever.
* Pull the plunger (5) by hand and check that the
plunger pin (3) fits into the groove (A) in the
solenoid lever.
(A)
(4)
(1)
(5)
(2)
(3)
1788M
Quick reverse solenoid adjustment
1. Turn the stitch length dial to the maximum setting.
2. Tilt back the machine head.
3. Check that the position of the solenoid lever screw (6)
can be verified when the machine head is restored to
its normal position.
(6)
1789M
0.2 - 0.5mm
(8)
(A)
(5)
(3)
Push
(7)
(6)
4. Return the machine head to its normal position, and
loosen the screw (6).
5. Check that the plunger pin (3) is in the groove (A) in
the solenoid lever.
6. With the reverse stitching lever (7) lowered all the way,
push the plunger (5) until the clearance between the
setting plate (8) of the quick reverse solenoid (1) and
the plunger (5) is 0.2 - 0.5 mm.
7. Tighten the screw (6).
* If the above clearance of 0.2 - 0.5 mm is large, the
operation of the quick reverse solenoid (1) will
become slower.
In addition, if the clearance is small, the impact
noise from the quick reverse solenoid (1) will
become more apparent.
(1)
1790M
SL-710A
52
6. ASSEMBLY
6-21. Bed under cover (Gear box)
1791M
(5)
(4)
(1)
(2)
(3)
1. Tilt back the machine head.
2. Insert the felt (1) into the gear box as shown in the
illustration.
3. Install the bed under cover (2) to the bed with the eight
screws (3).
* Be careful not to clamp the felt (1) at this time.
4. Pour 70 ml of lubricating oil in through the oil filler hole
(4), and insert the rubber cap (5). (When the felt has
absorbed the lubricating oil, the oil level will be
reduced by about 50 ml.)
* Use only the lubricating oil (Nisseki Mitsubishi
Sewing Lube 10N; VG10) specified by Brother.
* Do not add more than the specified volume of
lubricating oil.
If you add too much lubricating oil, it may result in oil
leaks.
5. For sub-classes -3[][] and -4[][], connect the knee lifter
connecting rod (6) and the knee lifter arm (7) by
tightening the shoulder screw (8).
Checking the amount of oil
Check the amount of oil inside the gear box according to
the method below which matches the model being used.
<DD7100A, 710A>
Refer to "Cleaning" in the Instruction Manual.
<DD7100>
Refer to SE Information No. 2001-019.
<-3 [][], -4[][]>
(7)
(6)
(8)
1792M
SL-710A
53
6. ASSEMBLY
6-22. Oil tank
<DD7100A, 710A>
1. Install the oil tank (1) to the bed with the two screws
(2).
2. Place the tube clip (4) onto the oil tube (3).
3. Insert the oil tube (3) into the sub tank (5), and clamp it
with the tube clip (4).
4. Insert the oil tube [L=110] (6) into the oil feeding pipe
(7), and insert oil tube MS (8) into the oil feeding pipe
(9).
5. Insert the oil tube (10) from the horizontal feed shaft
into the hole (11) at the rear of the oil tank (1).
(11)
(10)
(5)
(9)
(7)
(4)
(3)
(1)
(6)
(8)
(2)
1793M
<DD7100>
1. Install the oil tank (1) to the bed with the two screws
(2).
2. Place the tube clip (4) onto the oil tube (3).
3. Insert the oil tube (3) into the oil gauge guide (5), and
clamp it with the tube clip (4).
4. Insert oil tube S (6) into the oil feeding pipe (7), and
insert oil tube M (8) into the oil feeding pipe (9).
5. Insert the oil tube (10) from the horizontal feed shaft
into the hole (11) at the rear of the oil tank (1).
6. Insert the oil tube (13) from the oil gauge guide (5) into
the terminal (14).
(11)
(13)
(10)
(9)
(5)
(7)
(4)
(3)
(14)
(1)
(6)
(8)
(2)
1794M
SL-710A
54
6. ASSEMBLY
6-23. Tension release wire
1795M
(7)
(1)
(2)
(6)
(8)
2 - 3 mm
1. With the holder (2) installed to the tension release wire
(1), pass the tension release wire (1) around the wire
holder (3) and install it to the solenoid lever (5) with the
two nuts (4).
* Tighten the two nuts (4) when the solenoid lever (5)
is at the center of the threaded part at the end of the
tension release wire (1).
2. Move the outside of the tension release wire (1) to the
position where the tension discs (7) start to open when
the solenoid plunger (6) is pressed by 2 - 3 mm, and
then tighten the set screw (8) to secure it in that
position.
* At this time, the holder (2) should be under the set
screw (8).
(3)
(4)
(5)
1796M
6-24. Ground wire
1. Secure the ground wire (1) to the bed with the screw
(2).
(The ground symbol (3) indicates the location.)
2. Group the ground wire (1), oil tube (4) [DD7100 only]
and thread trimmer solenoid cord (5) together in that
order, and secure them together with the cord holder
(6).
(2)
(6)
(3)
(5)
(4) DD7100 only
(1)
1797M
6-25. Operation panel
1. Pass the cord (2) of the operation panel (1) through
the hole in the arm.
2. Insert the two panel support brackets (3) into the
mounting holes.
3. Install the operation panel (1) to the arm, and then
secure it by tightening the two set screws (4).
(4)
(3)
(2)
(1)
1798M
SL-710A
55
6. ASSEMBLY
4. Pass the cord (2) of the operation panel (1) under the
arm as shown in the illustration.
(2)
1799M
6-26. Face plate and thread take-up cover
1. Install the face plate (1) to the arm with the three
screws (2).
2. Install the thread take-up cover (3) to the arm with the
screw (4).
3. Install the needle (5).
(4)
(3)
(2)
(1)
(5)
(2)
1800M
4. Pass the thread wiper cord (6) under the arm as
shown in the illustration.
5. Secure the thread wiper cord (6) together with the
reverse actuator cord (7) using the cord holder (8).
<DD7100A, 710A>
(8)
(6)
(7)
<DD7100>
(8)
(7)
(6)
1801M
SL-710A
56
6. ASSEMBLY
6-27. Safety switch
1. Tilt back the machine head.
2. Install the safety switch (1) to the bed with the washer
(2) and screw (3).
(3)
(2)
(1)
1802M
6-28. Arm cover, rear cover and bobbin winder tension assembly
1. Install the arm cover (1) to the arm with the four
screws (2).
2. Install the rear cover (3) to the arm with the seven
screws (4).
3. Insert the bobbin wider tension (5) into the mounting
hole so that it faces as shown in the illustration, and
then secure it with the set screw (6).
(5)
(2)
(1)
(6)
(4)
(3)
1803M
6-29. Other devices
Refer to the Instruction Manual for details on installing other devices.
SL-710A
57
6. ASSEMBLY
6-30. Connectors
1. Insert the pins for the solenoid cords and the safety
switch cord into the sewing machine 14P connector
(1).
• Match the numbers on the sewing machine 14P
connector (1) with the numbers (tube marks) (2) on
each pin.
• Insert the split ends (A) of each pin so that they face
toward the locking mechanism (B) for the sewing
machine 14P connector (1).
1804M
(2)
(A)
(B)
(1)
(5)
(6)
14P
1
2
3
4
5
6
7
(3)
(1)
(8)
(7)
(4)
(9)
1805M
Code
(Ground wire)
Thread trimmer solenoid
Thread wiper
Quick reverse solenoid
Reverse actuator
Safety switch
14P
8
9
10
11
12
13
14
Code
Thread trimmer solenoid
Thread wiper
Quick reverse solenoid
Reverse actuator
Safety switch
2. Insert the sewing machine 14P connector (1), the
lower thread detector mechanism 8P connector (3),
the solenoid-type presser lifter connector (4), the
synchronizer connector (5) and the operation panel
connector (6) into the control box circuit board.
3. Insert the motor connector (7) into the side of the
control box.
4. Bind the cords together with a cable tie (8).
5. Tilt back the machine head.
6. Close the control box cover (9).
* Be careful not to clamp the cords inside the control
box.
7. Bind the cords with a cable tie (10).
(10)
1806M
SL-710A
58
6. ASSEMBLY
6-31. Lubrication
Use only the lubricating oil (Nisseki Mitsubishi Sewing Lube 10N; VG10) specified by Brother.
<DD7100A, 710A>
1. Pour 130 ml of lubricating oil from the accessory oil
bottle (2) in through the oil filler hole (1).
* Do not pour all of the lubricating oil in at once at this
time. Pour the lubricating oil bit by bit while checking
the oil gauge to make sure that the lubricating oil
does not overflow from the oil filler hole (1)
2. Check that the oil gauge comes to the upper reference
line in the oil gauge window (3).
(2)
(1)
(3)
Upper reference line
Oil gauge
Low reference line
0783M
<DD7100>
1. Remove the oil tank cap (1), and pour in 120 ml of
lubricating oil from the accessory oil bottle (2).
(Use the reference line as a guide when pouring.)
2. Replace the oil tank cap (1).
(1)
(2)
Reference line
1807M
3. Return the machine head to its original position.
4. Check that the oil gauge comes to the upper reference
line in the oil gauge window (3).
(3)
Upper reference line
Oil gauge
Low reference line
1808M
SL-710A
59
6. ASSEMBLY
6-32. Bed cover and knee lifter lever
1. Install the bed cover (1) to the bed.
2. For sub-classes -30[], -31[], -40[] and -41[], push the
knee lifter lever (2) onto the knee lifter shaft (3).
(3)
(1)
(2)
(DD7100A,710A)
(DD7100)
1809M
SL-710A
60
6. ASSEMBLY
6-33. Test operation
CAUTION
Do not touch any of the moving parts or press any objects against the machine while sewing, as this may result
in personal injury or damage to the machine.
For machines with a lower thread detector, set the lower
thread remainder limit before carrying out test operation.
(2)
Turning on the power
Press the ON power switch (1).
The power indicator (2) will illuminate.
(1)
0789M
0790M
0791M
Treadle
(A)
(B)
(C)
Test operation
1. Check that the machine sews at low speed when the
treadle is gently pressed to position (B).
Then check that it sews at high speed when the
treadle is gently pressed to position (C).
2. After pressing the treadle forward, check that the
needle is lowered to the top of the needle plate when
the treadle is returned to the neutral position (A) [when
needle down stopping has been set].
3. If the treadle is pressed to position (D) [or if it is
pressed to position (D) and then returned to the
neutral position (A)], thread trimming is carried out and
the needle then rises above the needle plate and
stops.
(D)
0792M
If the sewing machine does not operate when the treadle is pressed
• If "of" is flashing on the operation panel, check the position of the safety switch. (Refer to the next page.)
If this does not solve the problem, refer to the description of error code "of" (page 144).
• If there is no error display on the operation panel, refer to page 140.
SL-710A
61
6. ASSEMBLY
6-34. Adjusting the safety switch position
1810M
The safety switch (1) is normally installed as shown in
figure (A).
However, if the processing method used for the table
leaves too much space between the machine head and
the table hole, it may adversely affect the operation of the
safety switch (1).
[A]
(1)
Adjustment method
The standard amount of clearance between the machine
head and the table hole is 1.25 mm. (At this time, the
clearance between the safety switch (1) and the table
hole is 4.5 mm.)
If the clearance is too great, place a washer (2) on the
machine head side as shown in figure (B) and re-install
the safety switch (1).
* If the position cannot be satisfactorily adjusted in this
way, add more washers of the same thickness.
(2)
[B]
Table
1.25 mm
Machine bed
(1)
(2)
4.5 mm
1811M
1812M
<Safety switch operation>
If the spring stroke is to small, the safety
switch will not operate.
(2)
Clearance
is too large
By changing the position of the safety switch, the
By changing
the be
position
of the safety switch,
required spring
stroke can
maintained.
the required spring stroke can be maintained.
(2)
4.5 mm
1813M
SL-710A
62
7. ADJUSTMENTS
7. ADJUSTMENTS
CAUTION
Maintenance and inspection of the sewing
machine should only be carried out by a qualified
technician.
Turn off the power switch and disconnect the
power cord from the wall outlet at the following
times, otherwise the machine may operate if the
treadle is de pressed by mistake, which could
result in injury.
When carrying out inspection, adjustment and
maintenance.
When replacing consumable parts such as the
rotary hook and knife.
Ask your Brother dealer or a qualified electrician to
carry out any maintenance and inspection of the
electrical system.
If any safety devices have been removed, be
absolutely sure to re-install them to their original
positions and check that they operate correctly
before using the machine.
If the power switch needs to be left on when
carrying out some adjustment, be extremely
careful to observe all safety precautions.
Use both hands to hold the machine head when
tilting it back or returning it to its original position.
If only one hand is used, the weight of the macnine
head may cause your hand to slip, and your hand
may get caught.
7-1. Adjusting the thread tension spring
(1)
<-[][]1, -[][]3>
6 - 8 mm
<-[][]5>
4 - 6 mm
(2)
(5)
(3)
(4)
Thread tension spring position
The standard position of the thread tension spring (1) is 6
- 8 mm [4 - 6 mm for -[][]5 models] above the surface of
the thread guide (3) when the presser foot (2) is lowered.
1. Lower the presser foot (2).
2. Loosen the set screw (4).
3. Turn the thread tension bracket (5) to adjust the spring
position.
4. Securely tighten the set screw (4).
0916M
1195M
Thread tension spring tension
The standard tension of the thread tension spring (1) is
0.1- 0.2 N for - [][] 1 models, 0.25 - 0.35 N for - [][]3
models, and 0.3 - 0.5 N for -[][]5 models.
1. Push the needle thread with your finger until it is
slightly higher than the thread tension bracket (5) and
so that the upper thread is not pulled out.
2. Pull the upper thread down until the thread tension
spring (1) is at the same height as the base of the
thread guide (3), and then measure the tension of the
thread tension spring(1).
3. Insert a screwdriver into the slot of the thread tension
stud (6), and turn the screwdriver to adjust the tension
of the thread tension spring (1).
Note: If using the tension gauge (7) (sold separately) to
measure the tension, take the reading from the
scale on the side of the red line.
(1)
(3)
(5)
(6)
Scale
(7)
<-[][]1>
0.1 - 0.2 N
<-[][]3>
0.25 - 0.35 N
<-[][]5>
0.3 - 0.5 N
0917M
SL-710A
63
7. ADJUSTMENTS
7-2. Adjusting arm thread guide R
The standard position of arm thread guide R (1) is the
position where the screw (2) is in the center of the
adjustable range for arm thread guide R. (1).
Becomes greater
Becomes less
*
(2)
To adjust the position, loosen the screw (2) and then
move arm thread guide R (1).
• When sewing thick material, move arm thread
guide R (1) to the left. (The thread take-up amount
will become greater.)
• When sewing thin material, move arm thread guide
R (1) to the right. (The thread take-up amount will
become less.)
0918M
7-3. Adjusting the presser foot height
The standard height of the presser foot (1) is 6 mm when
the presser foot (1) is raised by means of the presser bar
lifter (2).
1. Loosen the nut (3) of the adjustment screw (4), and
then turn the adjustment screw (4) so that there is no
pressure applied to the presser foot.
2. Raise the presser bar lifter lever (2). The presser foot
(1) will also rise.
3. Remove the oil cap (5).
4. Loosen the bolt (6) and then move the presser bar (7)
up or down until the presser foot (1) is at the standard
height of 6 mm.
5. Tighten the bolt (6).
6. Replace the oil cap (5).
7. Adjust the presser foot pressure using the adjustment
screw (4), and then tighten the nut (3).
(4)
(3)
(6)
(5)
(2)
(7)
(1)
6 mm
1196M
SL-710A
64
7. ADJUSTMENTS
7-4. Adjusting of the feed dog height
The standard height of the feed dog (1) when it is at its
maximum height above the top of the needle plate is 0.8
mm for -[][]1/[][]3 models, and 1.2 mm for -[][]5 models.
<-[][]1, -[][]3>
0.8 mm
<-[][]5>
1.2 mm
(1)
1930M
(6)
(5)
(4)
(4)
Becomes
higher
(3)
(2)
Becomes
lower
(3)
(2)
1814M
1. Turn the pulley until the feed dog (1) rises to the
highest position.
2. Tilt back the machine head.
3. Loosen screw (2).
4. Turn the feed lifting rock bracket stud (3) within a
range of 90° from the reference line (4) to adjust the
vertical height of the feed bar (5). (Fig.[A])
5. Tighten the screw (2).
* If you are worried about the angle of the feed dog (1),
turn the shaft (6) while carrying out the above
adjustment. (Figure (B))
(Refer to "7-5. Adjusting the feed dog angle" on the
next page for details of this operation.)
[A]
Becomes higher
(3)
Needle plate
(1)
(2)
Standard
Becomes lower
1815M
[B]
Becomes higher
Becomes higher
(3)
(6)
(1)
Standard
Becomes lower
Standard
Becomes lower
1816M
SL-710A
65
7. ADJUSTMENTS
7-5. Adjusting the feed dog angle
(2)
(3)
Raise the front
(2)
(4)
Lower
the front
(5)
(3)
1817M
[C]
Raise the front
Parallel
Needle
plate
(2)
The standard angle for the feed dog (1) when it is at its
highest position above the needle plate is when the “ ”
mark (or V groove) on the shaft (2) is aligned with the feed
rocker bracket arm (3) and the feed dog (1) is parallel to
the needle plate.
1. Turn the machine pulley to move the feed dog (1) to its
highest position above the needle plate.
2. Tilt back the machine head.
3. Loosen the two set screws (4).
4. Turn the shaft (2) in the direction of the arrow within a
range of 90° with respect to the standard position. (Fig.
[C])
* In order to prevent puckering, lower the front of the
feed dog (1).
* In order to prevent the material from slipping, raise
the front of the feed dog (1).
5. Securely tighten the set screws (4).
(4)
(1)
*
Standard
*
Lower the front
1818M
[D]
Raise the front
Back is lowered
(2)
(5)
(1)
Standard
Back is raised
If you would like to tilt the feed dog (1) further, turn the
feed lifting rock bracket stud (5) while carrying out the
above adjustment. (Figure [D])
(Refer to "7-4. Adjusting the feed dog height" on the
previous page for details of this operation.)
The height of the feed dog (1) will change after the
angle has been adjusted, so it will be necessary to readjust the height of the feed dog (1).
Standard
Lower the front
1819M
SL-710A
66
7. ADJUSTMENTS
7-6. Adjusting the needle bar height
(2)
0924M
(1)
(a)
DB X 1
DA X 1
DP X 5
Reference line (a), which is the second line from the
bottom of the needle bar (1)(fourth line from the bottom
when using a DA X 1 needle) should be aligned with the
lower edge of the needle bar bush D (2) as shown in the
illustration when the needle bar (1) is at its lowest position.
1. Turn the machine pulley to set the needle bar (1) to its
lowest position.
2. Remove the oil cap (3).
3. Loosen the screw (4) and then move the needle bar
(1) up or down to adjust its position.
4. Securely tighten the screw (4).
5. Replace the oil cap (3).
(4)
(1)
(3)
1197M
7-7. Adjusting the needle and feed mechanism timing
0926M
<For thin and medium-thick materials>
<For thick materials>
Approx. 3 mm
Approx. 1 mm
(2)
(2)
(1)
(1)
(3)
(C)
(4)
(5)
(B)
[C]
Needle timinig is
Advanced
[A]
[B]
(Standard)
Needle timinig is
retarded
0927M
The standard position for point of the needle is as
described below when the feed dog (1) is lowered from its
highest position until it is aligned with the top of the needle
plate (2). (At this time, the “ ” mark (4) on the vertical cam
(3) should be aligned with the “-“ mark on the lower shaft.
Refer to [A] in the illustration.)
[For thin and medium-thick materials]
The top of the feed dog (1) and the top of the
needle plate (2) should be aligned, and the point of
the needle should be approximately 1 mm below
the needle plate (2).
[For thick materials]
The top of the feed dog (1) and the top of the
needle plate (2) should be aligned, and there
should be a clearance of approximately 3 mm
between the point of the needle and the needle
plate (2).
1. Tilt back the machine head. (Refer to page 8.)
2. Loosen the two set screws (5), and then turn the
vertical cam (3) sligtly to adjust the timing.
• If setting the timing to the standard timing, turn the
vertical cam (3) until the “ ” mark (4) is aligned with
the “-“ mark on the lower shaft ([A] in the illustration).
• To prevent material slippage from occurring, retard
the needle timing. (Turn the vertical cam (3) in the
direction of (B). Refer to [B] in the illustration.)
• To improve thread tightening, advance the direction
of (C). Refer to [C] in the illustration.)
Note: Do not turn the vertical cam (3) too far in the
direction of (C), otherwise it could cause the
needle to break.
3. After adjustment is completed, securely tighten the
two screws (5).
SL-710A
67
7. ADJUSTMENTS
7-8. Adjusting the needle and rotary hook timing
0928M
0929M
(2)
(4)
(1)
0 - 0.5 mm
1.8 mm
(b)
DB X 1
(3)
DA X 1
DP X 5
0 - 0.05 mm
0 - 0.05 mm
(3)
(5)
The tip of the rotary hook (3) should be aligned with the
center of the needle (4) when the needle bar (1) moves
up from its lowest position to the position where reference
line (b), which is the line at the bottom of the needle bar
(1) (third line from the bottom when using a DA X 1
needle), is aligned with the lower edge of the needle bar
bush D (2) as shown in the illustration.
1. Turn the machine pulley to raise the needle bar (1)
from its lowest position until reference line (b) is
aligned with the lower edge of the needle bar bush D
(2) as shown in the illustration.
(The needle should rise by 1.8 mm [2.2 mm for -[][] 5
specifications] and the distance from the needle hole
to the tip of the rotary hook should be 0 - 0.5 mm.)
2. Loosen the set screws (5), and then align the tip of the
rotary hook (3) with the center of the needle (4).
The distance between the tip of the rotary hook (3)
and the needle (4) should be approximately 0 - 0.05
mm.
3. Securely tighten the set screws (5).
1078M
Checking the clearance between the rotary hook
and bobbin case holder position bracket
Check that the clearance between the rotary hook (6) and
the bobbin case holder position bracket (7) is enough to
allow the thread being used to pass through smoothly.
The clearance should be 0.4 - 0.7 mm for light and
medium-weight materials, and 0.6 - 0.9 for heavy-weight
materials.
<Seen from above>
(7)
(6)
(6)
(7)
<Light and medium-weight materials>
0.4 - 0.7 mm
<Heavy-weight materials>
0.6 - 0.9 mm
1820M
1821M
SL-710A
68
7. ADJUSTMENTS
7-9. Quick reverse mechanism
1.
2.
3.
4.
(1)
5.
6.
1789M
7.
0.5 - 0.7 mm
(5)
(A)
(6)
(2)
8.
Push
(3)
Turn the stitch length dial to the maximum setting.
Remove the rear cover.
Tilt back the machine head.
Check that the position of the solenoid lever screw (1)
can be verified when the machine head is restored to
its normal position.
* If the automatic presser lifter has been installed,
remove it. (Refer to page 17.)
Return the machine head to its normal position, and
loosen the screw (1).
Check that the plunger pin (2) is in the groove (A) in
the solenoid lever.
With the reverse stitching lever (3) lowered all the way,
push the plunger (6) until the clearance between the
setting plate (5) of the quick reverse solenoid (4) and
the plunger (6) is 0.5 - 0.7 mm.
Tighten the screw (1).
* If the above clearance of 0.5 - 0.7 mm is large, the
operation of the quick reverse solenoid (4) will
become slower.
In addition, if the clearance is small, the impact
noise from the quick reverse solenoid (4) will
become more apparent.
(4)
(1)
1790M
7-10. Matching stitch lengths for normal feed and reverse feed
1822M
Normal feed
Reverse feed
11 stitches
(1)
(2)
Normal feed length becomes
smaller
(2)
Normal feed length
becomes longer
The following operation matches the stitch lengths for
normal feed and reverse feed.
1. Turn the stitch length dial to the "3" setting.
2. At a low sewing speed (220 rpm), sew using normal
feed and using reverse feed (11 stitches in each
direction)
3. If adjustment is required, carry out the following.
1) Tilt back the machine head.
* If the automatic presser lifter has been installed,
remove it. (Refer to page 17.)
2) Loosen the screw (1).
3) Adjust by turning the eccentric pin (2) within a range
of 90°. (If the eccentric pin (2) is turned more than
90°, the adjustment will be reversed.)
• If the stitch length is larger for normal feed
than for reverse feed
Turn the eccentric pin (2) clockwise.
• If the stitch length is smaller for normal feed
than for reverse feed
Turn the eccentric pin (2) counterclockwise.
4) After adjusting, securely tighten the screw (1).
1823M
SL-710A
69
7. ADJUSTMENTS
7-11. Synchronizer Adjustment
0931M
Needle down position
19 - 25 mm
0741M
(2)
Needle up position
<-[][]1>
8 - 10.5 mm
<-[][]3>
10 - 12.5 mm
<-[][]5>
12.5 - 15 mm
Becomes lower
The synchronizer uses a single element to detect the
needle up stop position. The needle down single is fixed.
Checking method
1. Turn on the power switch.
2. Stop the machine with the needle in the needle down
position.
Check that the distance from the top of the needle
plate to the bottom edge of the needle set screw is 19
- 25 mm at this time.
3. After the thread is trimmed, stop the machine with the
needle in the needle up position.
4. Check that the distance from the top of the needle
plate to the tip of the needle is within the value shown
in the illustration in accordance with the machine
model.
Adjusting the needle up stop position.
1. Turn off the power switch.
2. Loosen the screw (1).
3. Move the screw (1) in the direction of rotation of the
machine pulley to raise the needle bar (2) to a higher
stop position.
Move the screw in the other direction to lower the
needle bar stop position.
4. Securely tighten the screw (1).
Note: Do not turn the pulley while the screw (1) is
loosened, otherwise other parts may become
damaged as a result of the looseness.
(1)
Becomes higher
0932M
SL-710A
70
7. ADJUSTMENTS
7-12. Adjusting the tension release wire
1824M
Open
2 - 3 mm
Opening
starts
(1)
(5)
(6)
(4)
If the tension discs stay open or if the upper thread pulls
out of the needle after thread trimming, carry out the
following adjustments.
* Lower the presser foot when making these
adjustment.
A. If the upper thread pulls out of the needle
(The tension release wire does not operate
enough during thread trimming)
• When the solenoid plunger (1) is pushed by 2 - 3
mm, the tension discs (2) start opening, and when
it is pushed all the way, the tension discs (2)
should always be open.
• When the solenoid plunger (1) is released, the
tension discs (2) close.
(3)
1. Loosen the nuts (3) and (4), and then push the
solenoid plunger (1) by 2 - 3 mm.
2. Tighten the left-side nut (3) until the tension discs (2)
start to open.
3. Check that the tension discs (2) open fully when the
solenoid plunger (1) is pushed all the way, and that the
tension discs (2) close when the solenoid plunger (1)
is released.
4. Tighten the right-side nut (4).
(2)
B. If the tension discs stay open
1. Check that the solenoid lever (5) has returned fully.
2. Check that the tension release wire (6) is not
stretched.
3. Adjust using nuts (3) and (4) as described above.
* If adjustment is not possible, adjust the tension of
the tension release wire (6). (Refer to 6-23 on page
55.)
0.5 - 1 mm
1795M
SL-710A
71
7. ADJUSTMENTS
7-13. Adjusting the treadle
0939M
(4)
(3)
(1)
(2)
Adjusting the treadle pressure
If the machine starts running at low speed when your foot
is simply resting on the treadle, or if the treadle pressure
is felt to be too weak, adjust the position (a to c) at which
the treadle spring (1) is hooked onto the treadle lever (2).
* The treadle pressure will increase from position a to
position c.
Adjusting the treadle return pressure
1. Loosen the nut (3) and turn the bolt (4).
The treadle return pressure becomes heavier as the
bolt (4) is tightened, and it becomes lighter as the bolt
(4) is loosened.
2. Tighten the nut (3).
Adjusting the treadle stroke
Remove the nut (5), and then move the connecting rod
joint (6) from the position in figure A to the position in
figure B. The treadle stroke will then be increased by
approximately 27 %.
* This adjustment will also affect the treadle pressure
and the treadle return pressure, so these setting
should be readjusted if necessary.
abc
B
A
(5)
(6)
(5)
(6)
0940M
SL-710A
72
7. ADJUSTMENTS
7-14. Adjusting the rotary hook lubrication amount
CAUTION
Be careful not to touch your fingers or the lubrication amount check sheet against moving parts such as
the rotary hook or the feed mechanism when checking the amount of oil supplied to the rotary hook,
otherwise injury may result.
Use the following procedure to check the amount of oil being supplied to the rotary hook when replacing the rotary hook
or when changing the sewing speed.
Note: If changing from the normal rotary hook to the rotary hook RP (lubrication - free rotary hook), a different
procedure should be followed. Refer to page 74 for further details.
0933M
Approx. 25 mm
(1)
Approx. 70 mm
(2)
Checking the lubrication amount
1. Run the machine at the normal sewing speed for
approximately 1 minute without sewing any material
(following the same start/stop pattern as when actually
sewing).
2. Place the lubrication amount check sheet (1)
underneath the rotary hook (2) and hold it there. Then
run the sewing machine at the normal sewing speed
for 8 seconds. (Any type of paper can be used as the
lubrication amount check sheet (1).)
3. Check the amount of oil which has spattered onto the
sheet.
Bed
5 - 10 mm
(1)
0934M
Spattered oil
Too much
Correct
Too little
0935M
(3)
Less oil
More oil
0936M
Adjusting the lubrication amount
1. Tilt back the machine head.
2. Turn the lubrication adjustment screw (3)
approximately 45° to adjust the lubrication amount.
• If the rotary hook lubrication adjustment screw (3) is
turned clockwise, the lubrication amount becomes
greater.
• If the rotary hook lubrication adjustment screw (3) is
turned counterclockwise, the lubrication amount
becomes smaller.
3. Check the lubrication amount again according to the
procedure given in “Checking the lubrication amount”
above.
* Turn the lubrication adjustment screw (3) and check
the lubrication amount repeatedly until the
lubrication amount is correct.
4. Check the lubrication amount again after the sewing
machine has been used for approximately two hours.
SL-710A
73
7. ADJUSTMENTS
When changing from the normal rotary hook to the rotary hook RP (lubrication-free rotary hook)
0937M
(3)
1. While referring to the instruction manual, replace the
rotary hook RP and the cap screw.
2. Tighten the lubrication adjustment screw (3) as far as it
will go, and then turn it back the other way about three
full turns.
(At this time, the head (A) of the lubrication adjustment
screw (3) should be almost flush with the edge (B) of
the bed.)
Note: If the sewing machine is used while the
lubrication adjustment screw (3) is in the fullytightened position, it will cause oil to leak out
through the gap between the rotary hook shaft (4)
and the bracket (5).
(4)
(5)
(3)
(A)
(B)
0938M
SL-710A
74
8. CONTROL SYSTEM
8. CONTROL SYSTEM
(5)
(6)
(1)
(3)
(4)
(2)
1825M
Turn on the power switch (1).
A. When the treadle is depressed
1. When the treadle (2) is depressed, a voltage corresponding to the amount of treadle depression is transmitted by the
treadle unit (3) to the control box (4).
2. The DD motor (5) that is directly linked to the sewing machine receives a voltage that corresponds to the treadle
depression amount from the control box (4), causing the DD motor (5) to operate at the speed represented by the
treadle depression amount, and this makes the sewing machine operate.
B. When the treadle is returned to the neutral position
1. When the treadle (2) is returned to the neutral position (when the operator's foot is removed from the treadle), a signal
indicating that the treadle is at the neutral position is transmitted by the treadle unit (3) to the control box (4), and the
electrical brake is then applied to slow the DD motor (5).
2. The encoder circuit board that is installed to the DD motor (5) sends a signal to the control box (4) so that the electrical
brake is applied in order to stop the sewing machine at the stopping position (needle up or needle down) set by the
pulley (6) that is attached to the DD motor (5).
C. When the treadle is depressed backward
1. When the treadle (2) is depressed backward, a signal indicating thread trimmer operation is transmitted by the treadle
unit (3) to the control box (4), and the DD motor (5) slows down to the thread trimming speed (inching speed).
2. The encoder circuit board that is installed to the DD motor (5) sends a signal to the control box (4) so that
the electrical brake is applied in order to stop the sewing machine at the needle up stopping position set by
the pulley (6) that is attached to the DD motor (5). The thread trimming operation is carried out
immediately before the sewing machine stops at the needle up stop position.
SL-710A
75
9. REMOVING AND INSTALLING THE CONTROL BOX
9. REMOVING AND INSTALLING THE CONTROL BOX
DANGER
Wait at least 10 minutes after turning off the power switch and disconnecting the power cord from the wall
outlet before opening the face plate of the control box. Touching areas where high voltages are present can
result in severe injury.
Removal
(2)
1. Remove the cable tie (1), and then disconnect the
connectors (2) to (6) from the sewing machine.
(4)
(5)
(3)
(1)
(1)
(6)
1826M
2. Disconnect the power supply connector (7) and the
motor connector (8).
(8)
(7)
1827M
3. Loosen the nuts (9) and (10) (without removing them).
4. Remove the bolt (11) and nut (12).
(11)
(10)
To rear
(9)
(12)
1828M
5. Pivot the control box around the bolt (13) and pull it out
to remove it from the table.
(13)
Installation
Install by following the removal procedure in reverse.
1829M
SL-710A
76
10. CONTROL BOX AND MOTOR RATING PLATE
10. CONTROL BOX AND MOTOR RATING PLATE
Control box
• Check the phase, voltage and type for the control box.
• Some specifications are identical for both single- and three-phase.
Model
MD-721:DD7100/Single-phase
MD-731:DD7100/Three-phase
MD-722: DD7100A/Single-phase
MD-732: DD7100A/Three-phase
MD-7220:SL-710A/Single-phase
MD-7320:SL-710A/Three-phase
Phase
Voltage (number in brackets indicates factory default setting)
1830M
Serial No.
NO. K 0 1 A 111 0 1
Design revision symbol (A, B, C...)
Year of manufacture (last two digits of year)
Month of manufacture (A - M)
Type
DD7100A,DD7100
*[ ] [ ] * [ ]
SL-710A
* [ ]*- [ ]***- [ ]*
Compliance
E
N
4 or 5
Others
CE compliant
None
Speed (limit speed setting)
3
4
5
6
7
7
8
9
A
B
3,000 rpm
3,500 rpm
4,000 rpm
4,500 rpm
5,000 (4,700) rpm
Treadle unit
G
H
77
4
6
No modulation forward & back first step
Modulation of forward & back first step
SL-710A
10. CONTROL BOX AND MOTOR RATING PLATE
Motor
Serial No.
NO. G 0 1 A 11111
Design revision symbol (A, B, C...)
Year of manufacture (last two digits of year)
Month of manufacture (A - M)
brother
MD720A
NO. G01A11111
DD7100A
brother
M-72A
NO. D02A22222
SL-710A
For DD7100A and SL-710A (J80829-001)
brother
MD710A
NO. G97D11111
For DD7100 (J80625-001)
1831M
SL-710A
DD7100
1832M
78
11. CONTROL CIRCUIT BOARD
11. CONTROL CIRCUIT BOARD
DANGER
Wait at least 10 minutes after turning off the power switch and disconnecting the power cord from the wall outlet
before opening the face plate of the control box. Touching areas where high voltages are present can result in
severe injury.
Name and function of each part
(1) (2)
(3)
(4)
(5) (6) (7)
(8)
(9)
(10)
(11)
(12)
(13)
(24)
(23)
(22)
(21) (20)
(19)
(18)
(17)
(16)
(15)
(14)
1833M
SL-710A
79
11. CONTROL CIRCUIT BOARD
Connectors
Fuses
Terminal board
DIP switch
Control dials
LED indicators
(17)
(18)
(2)
Name
Operation panel connector
Synchronizer connector
Lower thread detector connector
Sewing machine connector
Solenoid-type presser lifter connector
Coupler connector
Relay connector
Treadle connector
Standing operation connector
Control power supply connector
Illumination lamp connector
Puller connector
Output power supply connector
Bobbin changer connector
Solenoid power supply fuse (8 A)
Illumination lamp power supply
fuse (5 A)
Terminal board
DSW
PVR
(21)
FVR
(6)
(7)
Red LED
Green LED
(5)
(8)
(10)
(11)
(12)
(4)
(3)
(1)
(23)
(14)
(20)
(9)
(15)
(22)
(13)
(19)
Function
Connect to sewing machine connectors.
Connect to power supply circuit board connectors.
Connect to treadle unit connector.
(Already connected for some specifications.)
Connect to transformer connectors.
For optional devices.
For preventing overcurrent
For illumination lamp (6 V)
8-element DIP switch (*1)
Coordinates the treadle unit (24) and control circuit
board (16). (*2)
Use to adjust the fluorescent tube and lamp if they
are flickering when the sewing machine starts. (*3)
Indicates power supply circuit board problems.
Indicates that the power is on.
*1: When using the automatic presser lifter, set DIP switch 2 to ON. If the sewing machine is used while DIP switch 2 is
set to OFF, the sewing machine may start operating before the presser foot is lowered. (Refer to page 81.)
*2: This is adjusted at the time of shipment from the factory, and should generally not be touched. However, it should be
adjusted when either the control circuit board (16) or treadle unit (24) is replaced. (Refer to page 92.)
*3: This is set to the right-most position at the time of shipment from the factory. The flickering is reduced if turned to the
left, but the sewing machine operation will become slower.
In addition, the maximum speed may become lower.
SL-710A
80
12. FUNCTION SETTING METHODS
12. FUNCTION SETTING METHODS
12-1. DIP switch functions
DANGER
Wait at least 10 minutes after turning off the power switch and disconnecting the power cord from the wall outlet
before opening the face plate of the control box. Touching areas where high voltages are present can result in
severe injury.
Control box
DIP switches
ON: Up
OFF: Down
0973M
1
Presser foot position when the foot pedal is
returned to the neutral position after thread
trimming
2
Setting of a delay from the time the presser foot is
turned OFF until the motor starts (See NOTE 2.)
3
ON
Presser foot is lowered. (Export specification)
OFF
Presser foot is kept raised. (Japanese specification
only) (See NOTE 1.)
ON
With delay
OFF
Without delay
ON
The machine stops with the needle at its highest
position due to reverse rotation.
OFF
The machine stops with the needle at its highest
position without reverse rotation.
Needle up stop position due to reverse rotation
ON
4
OFF
5
Spare
6
Limited speed setting 1
7
Limited speed setting 2
Maximum sewing speed (during high-speed sewing)
that can be through the operation panel (See NOTE
3.)
8
Always set to off. (See NOTE 4.)
(NOTE 1) Once the knee lifter switch is used to lower the presser foot, the foot pedal can not be used to raise the
presser foot while the machine is stopped; at this time, only the knee lifter is able to raise and lower the
presser foot.
(NOTE 2) For -900 series specification macnines (machines with an automatic presser foot lifter), be sure to set DIP
switch 2 to on.
(NOTE 3) Limited sewing speeds depend on settings for DIP switches 6 and 7 as shown in the following table. When
the maximum sewing speed is specified as 5,000 rpm on the operation panel, it is actually limited to 4,700
rpm.
If the setting of memory switch 04 is changed to on, the set sewing speed is not limited to 4,700 rpm.
DIP switch 6
DIP switch7
Limited speed
OFF
OFF
3,500 rpm
ON
OFF
4,000 rpm
OFF
ON
4,500 rpm
ON
ON
5,000 rpm
(NOTE 4) If DIP switch 8 is set to on, all pedal operations are deactivated. Be sure to set it to off.
SL-710A
81
12. FUNCTION SETTING METHODS
12-2. Parameter setting flowchart
Start
• Set memory switch 01 to ON. *1
• Turn off all LEDs.
For the B-100 operation panel, select
pattern 1.
• Leave the machine stopped after thread
trimming.
• Press the thread trimming and AUTO
keys. (The LED of the thread trimming
key will blink, and a parameter number
will appear on the AB displays.)
The data currently set for the parameter can
be checked only while the key below the A
display is kept pressed. *2
• Select the desired parameter number using
the
and
keys below the B display.
Change
other parameter setting
or finish setting?
Finish
Change
• Press the thread trimming key. (The
Changing
Completely?
value corresponding to the currently set
parameter number will blink.)
No more changes
Further changes
• Change the value using the
below the AB displays. *3
Related to
and
keys
• Indicate parameter number
99 using the
and
keys
below the B display.
• Indicate parameter number
90.
No
backtacking?
Yes
• Press the thread trimming
key.
• Press the thread trimming keys. (The
plus or minus symbol currently selected
will blink.)
• Select the plus or minus symbol using
the key below the B display. *4
End
• Press
the thread trimming key.
(Parameter number will reappear.)
*1: Refer to the memory switch setting flowchart.
*2: As to the data related to backtacking, press the
key to indicate the timing angle
(X15°) and
key to indicate a plus or minus symbol.
*3: As to backtacking information, the timing angle (X15°) will appear.
*4: Select a plus <
> or minus symbol <
> for the value determined in *3.
SL-710A
82
12. FUNCTION SETTING METHODS
12-3. Parameters
The parameter numbers appear on the panel.
Parameter No.10 - 33
Parameter No.
Default value
Data value setting range
10
15 (150 ms)
00 - 25 [X10] (0 - 250 ms)
11
05 (50 ms)
03 - 10 [X10] (30 - 100 ms)
01 - 10
Function
Time delay from the time the machine starts to operate
with the automatic presser foot raised to the time the
moter operates.
Time delay from the time the thread wiper turns OFF
until the automatic presser foot turns ON
Time from when lower thread solenoid finally turns
OFF to when motor can operate
12 *1
03
(From
design
change B onward)
13
30 (300 ms)
10 - 90 [X 10] (100 - 900 ms)
Time to keep the automatic presser foot lifter raised
14 (a)
36 (3 min)
00 - 60 [X 5] (5sec - 5 min)
15 (b)
00 (30ms)
00 - 60 [X 2.5] (0 - 150 ms)
16
12
10 - 12
17
10 (10s)
05 - 30 (5 - 30 s)
The presser foot signal will be automatically off after the
set time passes. When the data is set to 00, the presser
foot signal is not automatically off.
Time from the presser foot lowering command to
when the presser foot momentarily turns ON
Detection voltage constant from the presser foot
lowering command to when the presser foot
momentarily turns ON
Continuous puller ON time
18
40 (40 stitches) 00 - 99 (0 - 99 stitches)
20
02 (20ms)
01 - 07 [X10] (10 - 70ms)
21
05 (50ms)
04 - 10 [X10] (40 - 100ms)
Number of stitches from sewing start to lowering of
puller
Time delay from end of thread trimming to the time
when thread wiper turns ON
Thread wiper ON time
22
50 (50ms)
40 - 70 [X1] (40 - 70ms)
Lower thread detect pin ON control time (all areas)
23
10 (10ms)
05 - 25 [X1] (5 - 25ms)
First ON time for lower thread detect pin
24
07 (7ms)
01 - 15 [X1] (1 - 15ms)
First OFF time for lower thread detect pin
26
03 (30ms)
00 - 05 [X10] (0 - 50ms)
27 (c)
05 (0.5s)
30
-04 (-60 °)
31
00 (0 °)
32
+02 (30 °)
33 (d)
-04 (-60 °)
Time delay from the time the thread wiper turns OFF to
the time when the lower thread detect pin turns ON
02 - 50 [X0.1] (0.2 - 5.0s)
Time delay from the time when the machine stops
with the needle at its highest/lowest position to the
lower thread detect pin ON (Lower thread detection
function at the needle up/down stop with the foot
pedal in neutral)
ON timing for quick reverse device during start
-23 to +23 (units of 15°)
(- appears as "-", and + backtacking and continuous backtacking
appears as " ".)
OFF timing for quick reverse device during start
-23 to +23 (units of 15°)
backtacking
and continuous backtacking
(- appears as "-", and +
appears as " ".)
OFF timing for quick reverse device during end
-23 to +23 (units of 15°)
backtacking.
(- appears as "-", and +
appears as " ".)
2nd ON timing for quick reverse device during
-23 to +23 (units of 15°)
double
end backtacking
(- appears as "-", and +
appears as " ".)
1834M
*1 ... Values are X10 ms.
Notes
(a) The timer-off function for the presser foot is activated only when memory switch 36 is set to off.
(b) The indicated parameters are only enabled when memory switch 35 is set to ON.
(c) The lower thread detection function for the needle up/down stop when the pedal is positioned at neutral is activated
only when memory switch 51is set to on.
(d) The indicated parameters are the settings when memory switch 22 is set to ON.
SL-710A
83
12. FUNCTION SETTING METHODS
Parameter No.P0 - S5
Parameter
Default value
No.
P0
00 (0 mm)
P1
P2
P3
P4
P5
S4
S5
Data value setting range
-07 - 07 [X0.25]
(-1.75 - 1.75 mm)
-01 (-0.25 mm) -05 - 05 [X0.25]
(-1.25 - 1.25 mm)
01 (0 mm)
-05 - 05 [X0.25]
(-1.25 - 1.25 mm)
00 (0 mm)
-05 - 05 [X0.25]
(-1.25 - 1.25 mm)
00 (0 mm)
-05 - 05 [X0.25]
(-1.25 - 1.25 mm)
00 (0 mm)
-06 - 06 [X0.75]
(-4.5 - 4.5 mm)
-01 (-0.25 mm) -02 - 02 [X0.50]
(-1.0 - 1.0 mm)
00 (0 mm)
-02 - 02 [X0.50]
(-1.0 - 1.0 mm)
Function
Thread trimmer operating point of depression stroke
Back automatic presser lifter operating point of
depression stroke
Forward automatic presser lifter operating point of
depression stroke
Low speed start operating point of depression stroke
Speed change starting point of depression stroke
Maximum speed reaching point of depression stroke
Speed change starting point of standing operation
variable speed pedal
Maximum speed reaching point of standing operation
pedal
With the value being 0 at the treadle neutral position, the value is positive when the treadle is depressed forward, and
negative when the treadle is depressed backward. The value is added to or deducted from the standard setting value.
(Refer to page 91 for details.)
(Example 1: Changing setting for P0)
Speed
Neutral
Depression stroke
1835M
(Example 2: Changing setting for P3)
Speed
Neutral
Depression stroke
1836M
(Example 3: Changing setting for P5)
Speed
Neutral
Depression stroke
1837M
SL-710A
84
12. FUNCTION SETTING METHODS
<Parameter time setting>
“T** ” in the diagram (where “**” is a two-digit number)
corresponds to the various parameter numbers.
Depressed forward
Depressed backward
Needle down signal
Needle up signal
Thread trimming
(with no lower thread)
Thread wiping
Lower thread
detector
Presser foot lifiting
Motor
1838M
SL-710A
85
12. FUNCTION SETTING METHODS
12-4. Memory switch setting flowchart
Start
• Leave the machine stopped after thread trimming
• Turn off all LEDs (except for the LED of the needle up/down stop key).
(For the B-100 operation panel, select pattern 1.)
• Press the needle up/down stop key while pressing the thread trimming
key.
(A memory switch number will appear on the AB displays, and either of
the two LEDs of the needle up/down stop key will be lit to indicate the
direction of movement. On the B-40 or B-100 operation panel, the setting
will be indicated on the D display.)
• Select the desired memory switch number using the
below the AB displays.
Indication when memory switch is set
and
keys
to off
• Press the needle up/down stop key to change the setting of the memory
switch.
And
(Either of the two LEDs of the needle up/down stop key will be lit. On the
B-40 or B-100 operation panel, the
and
keys below the D display
0975M
can be used instead.)
Indication when memory switch is set
Change
to on
Change other memory switch setting
or finish setting?
Finish
And
• Keep pressing the thread trimming key at least for 1 second to cause a
beep to be issued.
(All LEDs except for the LED of the needle up/down stop key will be
0976M
turned off.)
End
(NOTE) If the power is turned off before the end operation, memory switch settings are not renewed.
SL-710A
86
12. FUNCTION SETTING METHODS
12-5. Memory switches
Memory switches 01 - 08
Parameter setting can be changed.
Parameter setting change is prohibited.
Forward step is possible during backward step
ON
(for thread trimming).
02 Interlocking along with forward step
Forward step is impossible during backward step
OFF
(for thread trimming).
Power supply drop check (reset detection) function is
ON
activated.
03 Power supply drop check
OFF
Without the above-mentioned function
The same as settings of DIP switches 6 and 7.
ON
(See NOTE 1.)
04 Limited sewing speed
OFF
Maximum sewing speed is limited to 4,700rpm.
ON
Needle penetration force is strong.
05 Needle penetration force
OFF
Needle penetration force is ordinary.
ON
Overtime function disabled
06 Overtime function
OFF
Overtime function enabled (3 minutes)
ON
Backtacking speed is not limited by high speed setting
Independent backtacking speed
07
setting
OFF
Backtacking speed is limited by high speed setting
Number of stitches and sewing speed can be set using the
ON
Slow start function (From design
operation panel
08
change C onward)
OFF
Low speed is fixed at 2 stitches
(NOTE 1) When the power is turned on again, sewing speed can be set up to 5,000 rpm.
01
Parameter setting
Memory switches 11 - 18
Thread trimming and thread wiper
11
output
Presser foot position after thread
12
trimming (See NOTE 2.)
Presser foot position after the machine
13
stops with the pedal in neutral
14
Actuator switch
15
Slowdown stop control
16
Lower thread remaining detection
17
Half-stitch correction
18
Reverse stitch correction
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
Without thread trimming and thread wiper
With thread trimming and thread wiper
Presser foot is raised when the foot pedal is in neutral.
Presser foot is lowered when the foot pedal is in neutral.
Presser foot is at its highest position.
Presser foot is at its lowest position.
It is used as the thread trimming switch.
It is used as the reverse and correction switches.
Ordinary slowdown stop and control
Slowdown and stop control with 1 stitch elimination
Unable to be used
Able to be used.
A forward stitch or half stitch can be corrected. (See NOTE 3.)
A forward stitch can be corrected. A half stitch cannot be
corrected. (See NOTE 3.)
A forward stitch or reverse stitch can be corrected.
(See NOTE 3.)
A forward stitch can be corrected. A reverse stitch cannot be
corrected. (See NOTE 3.)
(NOTE 2) It is activated when DIP switch 1 is set to on.
(NOTE 3) A forward stitch can be corrected when the LED of the correction switch is lit. A half stitch or reverse stitch can
be corrected when the LED of the correction switch is not lit.
SL-710A
87
12. FUNCTION SETTING METHODS
Memory switches 21 - 28
21
ON
Double start backtacking
OFF
ON
22
Double end backtacking
OFF
Number of stitches for
backtacking plus 10 stitches
start
24
Number of stitches for
backtacking plus 10 stitches
end
25
Feed direction when the
backtacking is completed
start
26
Start end backtacking
27
Continuous backtacking setting
23
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
28
Number of stitches for continuous
backtacking plus 10 stitches
ON
OFF
Start backtacking is performed in the order of lengths A, B, A,
then B.
Start backtacking is performed in the order of lengths A and B.
End backtacking is performed in the order of lengths C, D, C,
and D (B, A, B, and A on the B-20 operation panel).
End backtacking is performed in the order of lengths C and
D (B and A on the B-20 operation panel).
Extra 10 stitches are added to the number of stitches set for
both lengths A and B.
No extra stitches are added.
Extra 10 stitches are added to the number of stitches set for
both lengths C and D
(B and A on the B-20 operation panel).
No extra stitches are added.
The machine will stop with the reverse feed remaining on.
The machine will stop after feed is returned to normal.
End backtacking will start without speed slowing down.
The machine will slow the sewing speed gradually to start
low speed sewing, then shift to end backtacking.
Forward stitching for the number of stitches set in the A
display, and backward stitching for the number of stitches set
in the B display will be performed repeatedly for the number
of times set in the D display. (The C display will be blank.)
Continuous stitching will be performed for lengths A, B, C,
and D as specified in the ABCD displays.
Extra 10 stitches are added to each lengths A, B, C, and D.
No extra stitches are added.
Memory switches 31 - 38
31
Start backtacking suspension by foot
pedal being placed in neutral or
backtacking speed change during the
start backtacking
ON
OFF
ON
32
The number of backtack stitches on
the B-20 or B-40 operation panel
33
Pleats presser stitching direction
34
-
35
Presser foot soft drop function
36
Presser foot timer-off function
37
Automatic presser lifter output selection
(From design change B onward)
38
(NOTE 4)
(NOTE 5)
(NOTE 6)
(NOTE 7)
OFF
ON
OFF
ON
OFF
ON
OFF
ON
Sewing can be suspended by returning the foot pedal to
neutral. During start backtacking, sewing speed depends on
the foot pedal stroke.
Sewing can not be suspended by returning the foot pedal to
neutral. During start backtacking, sewing speed is fixed
regardless of the foot pedal stroke.
The number of backtack stitches for fixed stitching, label
attaching, or pleats presser sewing can be changed.
The number of backtack stitches is fixed to 4 (for fixed
stitching, label attaching, and pleats presser sewing) (See
NOTE 4)
Without reverse stitching (Fixed stitching will be called back.)
With reverse stitching (Ordinary pleats presser stitching)
Manual soft drop function (NOTE 5)
Automatic soft drop function (NOTE 6)
Timer-off function is not activated. (Presser foot will not be
lowered by timer.)
Timer-off function is activated. (See NOTE 7)
Pneumatic-type presser lifter-compatible (Duty 1:1)
Solenoid-type presser lifter-compatible (Duty 1:6)
OFF
ON
OFF
ON
OFF
For the B-40 operation panel, the number of end backtack stitches can be changed for fixed stitching or
pleats presser sewing.
Adjustment is required using parameter No. 15. If set to "00", response is fastest and operating noise increases.
Can be adjusted using parameter No. 16. If set to "10", response is fastest and operating noise increases.
Timer-off function is not activated when parameter No.14 is set to 00.
SL-710A
88
12. FUNCTION SETTING METHODS
Memory switches 41 - 48
ON
41
Mode after lower thread alarm
42
Rotary hook used with the lower
thread detector
43
(See NOTE 8.)
44
(See NOTE 8.)
45
Delayed start of standing operation
46
Emergency stop by presser lifter
pedal during standing operation
47
48
Emergency stop using variable speed
pedal during standing operation
Lifting the presser foot using thread
trimming pedal during standing
operation
ON
Foot pedal can be used after lower thread alarm.
After lower thread alarm, the foot pedal operation is
deactivated until the cancel key is pressed.
1.7-time rotary hook
Standard rotary hook
Be sure to set to off.
Be sure to set to off
Without any delay.
With a delay (for 80 ms).
Impossible to make an emergency stop using presser lifter
pedal
During automatic sewing, emergency stop can be
performed using presser lifter pedal.
Impossible to make an emergency stop using variable
speed pedal.
During automatic sewing, emergency stop can be
performed using variable speed pedal.
It is always deactivated after the presser lifter pedal is used.
OFF
It is activated.
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
Memory switches 51 - 58
51
52
Lower thread detection after the
machine is stopped by putting foot
pedal in neutral (See NOTE 9).
Needle up/down stop key operation
53
54
Actuator correction stitches after
thread trimming ends (From design
change B onward)
55
56
57
58
ON
OFF
ON
Lower thread is detected while the machine is stopped by
putting foot pedal in neutral for the specified time.
Lower thread is not detected after the machine is stopped
by putting foot pedal in neutral.
Needle up/down stop key operation is deactivated. (Needle
stop position cannot be changed.)
Needle up/down stop key operation is activated.
OFF
ON
OFF
ON
Correction enabled
OFF
Correction disabled
ON
OFF
ON
OFF
ON
OFF
ON
OFF
(NOTE 8) Do not change these settings.
(NOTE 9) The time for delay can be changed in parameter No.27. If the foot pedal is pushed forward within the time,
lower thread will not detected. The default delay is 0.5 seconds.
This function is available for sewing process without thread trimming.
Memory switch 61
Puller output selection (lifting/lowering
61
the puller)
ON
OFF
Synchronizer signal output
Puller output
SL-710A
89
13. TREADLE UNIT ASSEMBLY
13. TREADLE UNIT ASSEMBLY
13-1.Types
• Two different types are available: a type that controls the automatic presser lifter, and a type does not control the
automatic presser lifter.
• The two specifications are changed over by (A) changing the attachment position of the spring (1) inside the treadle
unit, and (B) resetting the depression stroke signal.
Specification
Treadle unit G
Operation
Does not control automatic presser lifter
[a]
<A>
Difference in spring
position
Treadle unit H
Controls automatic presser lifter
[b]
(1)
(1)
1839M
<B>
Signal setting
Depression force
Depression signal
1840M
Carry out the setting in "Setting method for Carry out the setting in "Setting method for
standard depression strokes" on page 92.
standard depression strokes" on page 92.
"F1" and "r1" are set at the neutral position.
"F1" and "r1" are set at the first modulation point
for the depression force.
<When depressed forward and depressed backward> <When depressed forward and depressed backward>
The depression force hardly changes at all from The depression force suddenly changes at a
the start of depression until full depression.
point between the start of depression and full
depression.
<When depressed forward and depressed backward> <When depressed forward and depressed backward>
No automatic presser lifter signal is output.
An automatic presser lifter signal is output at the
point before the depression force suddenly
changes, and the sewing machine starts at the
point after the depression force suddenly
changes.
SL-710A
90
13. TREADLE UNIT ASSEMBLY
13-2.Standard setting values
Parameter
No.
Symbol
Specification
(diagram Operation
below)
Spring position setting
Function
-
S0
Treadle unit G
Does not control automatic
presser lifter
No forward/back 1st step
modulation (Figure [a] on
previous page)
Length from S0
Force (N)
(mm)
0
-
Treadle unit H
Controls automatic presser lifter
Forward/back 1st step modulation
(Figure [b] on previous page)
Length from S0
(mm)
0
Force (N)
Neutral point
Forward
automatic
P2
S1
presser lifter operating
2 (*1)
10
point
Low speed operation
P3
S2
3
10
5
25
starting point
Speed change starting
P4
S3
6
7
point
Maximum
speed
P5
S4
S5-1
S5-1
reaching point
Maximum
forward
S5
14.5
12
14.5
32
depression point
Back automatic presser
P1
S6
2 (*2)
14
lifter operating point
Thread
trimmer
P0
S7
5
22
5
35
operating point
Maximum
back
S8
8
28
8
43
depression point
*1 : Enabled when DIP switch 1 is ON and memory switch 13 is ON.
*2 : Enabled when memory switch 13 is OFF.
• When the connecting rod installation position is on the inside, the measurement value is the amount of movement of the
treadle from the neutral position to the forward position and to the backward position.
• For treadle unit -H, the point of change (F) in the forward depression force is between S1 and S2, and the point of
change (R) in the backward depression force is between S6 and S7.
Speed
Backward
depression
Neutral
Forward
depression
SL-710A
91
1841M
13. TREADLE UNIT ASSEMBLY
13-3. Setting method for standard depression strokes
CAUTION
If the power switch needs to be left on when carrying out some adjustment, be extremely careful to observe all
safety precautions.
When the specifications of the treadle unit are changed or if the treadle unit or control circuit board are replaced, it will be
necessary to make new settings according to the procedure described below.
Use the following procedure to set the operating positions for the depression stroke.
1) Signal setting entry
1. Set DIP switch No.8 to ON.
2. Turn on the power switch.
(1)
1842M
(2)
(3)
3. Press the thread trimming key (2) and the AUTO key
(3) simultaneously.
“FF” will appear in columns A and B (4) of the display
window.
(4)
1843M
(2)
4. Press the thread trimming key (2).
A value of “05” or higher will flash in columns A and B
(4) of the display window.
(4)
1844M
SL-710A
92
13. TREADLE UNIT ASSEMBLY
2) Memorizing the maximum forward position
• Carry out the following procedure while pressing the treadle forward as far as it will go.
0844M
1. Turn the PVR so that “45” appears in columns A and B
(4) of the display window.
(4)
1845M
(2)
2. Press the thread trimming key (2).
“nn” will flash in columns A and B (4) of the display
window.
(4)
1846M
3) Memorizing the neutral position
• Carry out the following procedure while removing your foot from the treadle.
1847M
1. Check the “nn” is flashing in columns A and B (4) of
the display window.
(4)
1848M
(2)
2. Press the thread trimming key (2).
“rr” will flash in columns A and B (4) of the display
window.
(4)
1849M
SL-710A
93
13. TREADLE UNIT ASSEMBLY
4) Memorizing the maximum backward position
• Carry out the following procedure while pressing the treadle backward as far as it will go.
1850M
1. Check that “rr” is flashing in columns A and B (4) of the
display window.
(4)
1851M
(2)
2. Press the thread trimming key (2).
“F1” will flash in columns A and B (4) of the display
window.
(4)
1852M
5) Memorizing the modulation position when pressing the treadle forward
• Press the treadle forward until the depression force suddenly becomes heavier, and hold the
pedal in that position while carrying out the following procedure. (For treadle unit H)
Press gently
• If the depression force of the pedal does not change suddenly when it is pressed forward, carry
out the following procedure with your foot removed from the pedal. (For treadle unit G)
Or in the
neutral position
1853M
1. Check that “F1” is flashing in columns A and B (4) of
the display window.
(4)
1854M
(2)
2. Press the thread trimming key (2).
“r1” will flash in columns A and B (4) of the display
window.
(4)
1855M
SL-710A
94
13. TREADLE UNIT ASSEMBLY
6) Memorizing the modulation position when pressing the treadle backward
Press gently
Or in the
neutral position
• Press the treadle backward until the depression force suddenly becomes heavier, and hold the
pedal in that position while carrying out the following procedure. (For treadle unit H)
• If the depression force of the pedal does not change suddenly when it is pressed backward,
carry out the following procedure with your foot removed from the pedal. (For treadle unit G)
1850M
1. Check that “r1” is flashing in columns A and B (4) of
the display window.
(4)
1856M
(2)
2. Press the thread trimming key (2).
“99” will flash in columns A and B (4) of the display
window.
(4)
1857M
7) Completion of setting
1. Check that “99” is flashing in columns A and B (4) of
the display window.
(4)
1858M
(2)
2. Press the thread trimming key (2).
Columns A and B (4) of the display window will be
cleared.
(4)
1859M
3. Turn off the power switch (1).
4. Set DIP switch No.8 to OFF.
(1)
1860M
SL-710A
95
14. STANDING OPERATION PEDAL
14. STANDING OPERATION PEDAL
Some sub-classes are not equipped with
a foot plug set.
In such cases, install the foot plug set
(J02953-001) by the following procedure.
<With foot plug set>
<Without foot plug set>
Foot plug
1861M
1862M
14-1. Installing the foot plug
DANGER
Wait at least 10 minutes after turning off the power switch and disconnecting the power cord from the wall outlet
before opening the face plate of the control box. Touching areas where high voltages are present can result in
severe injury.
1. Remove the three screws (1), and then remove the
treadle unit (2).
(2)
(1)
1863M
2. Install the foot plug (3).
3. Install the ground wire with the screw (4).
(3)
(3)
1864M
4. Insert the connector (5) of the foot plug (3) into the
CN3 connector of the control circuit board.
5. With the connector (5) passed through the opening (6),
install the treadle unit (2) with the three screws (1).
(6)
(2)
(5)
<CN3>
1865M
SL-710A
96
14. STANDING OPERATION PEDAL
14-2. Connectors
At control box
No.
1
2
3
4
5
6
7
8
9
Standing
operation
pedal
9P connector
DC+8 V
High-speed switch
Thread trimmer switch
SOV
Spare
Low-speed switch
Presser foot switch
Variable speed input
Ground
1866M
At pedal
<Note>
Connector types
Manufacturer
MOLEX
Connector No.
1292 P
Connector terminal
1380 TL
1867M
<B> Variable speed pedal
<A> Two-step pedal
Presser foot
Low speed
Thread trimming
High speed
Presser foot
Low speed
Thread trimming
High speed
SL-710A
97
1868M
15. Puller (commercially available)
15. Puller (commercially available)
DANGER
Wait at least 10 minutes after turning off the power switch and disconnecting the power cord from the wall outlet
before opening the face plate of the control box. Touching areas where high voltages are present can result in
severe injury.
15-1. Timing
Obtain the puller output from the CN15 connector on the
control circuit board.
• The puller is lowered after the 40th stitch from the
sewing start.
• After the sewing machine stops, it is raised together
with the automatic presser lifter, and then after 10
seconds it is lowered.
Note:
The 40th stitch and 10 seconds settings given above can
be changed by changing the parameter settings.
<CN15>
1869M
15-2. Connector
The following puller connector is provided.
Part name
Puller connector assembly
Part code
J03126-001
<Note>
If purchasing the connector as a single part from the
manufacturer, specify the following number.
Manufacturer
MOLEX
Connector No.
5557-10R
Connector terminal
5556PBTL
Terminal puller
57031-6000
(1) Puller output
(6) Puller power supply
1870M
15-3. Binding the cord
Secure the puller cord (1) using a cable tie (2).
(2)
(1)
1871M
SL-710A
98
16. AUTO BOBBIN CHANGER
16. AUTO BOBBIN CHANGER
DANGER
Wait at least 10 minutes after turning off the power switch and disconnecting the power cord from the wall outlet
before opening the face plate of the control box. Touching areas where high voltages are present can result in
severe injury.
16-1. Timing
Obtain the bobbin changer signal from the CN6 connector
on the control circuit board.
• When the lower thread amount is detected, a "L"
signal is output from pin (3) of CN6 for 500 ms.
• The motor will not operate while a "L" signal is being
output from pin (2) of CN6.
<CN16>
1872M
16-2. Connector
The following bobbin changer connector is provided.
Part name
Part code
Bobbin changer connector
J03136-001
assembly
1873M
1874M
<At control circuit board>
Note: If purchasing the connector as a single part from
the manufacturer, specify the following number.
(1) DC5V
Manufacturer
Connector No.
Connector terminal
(2) Input from bobbin changer
(3) Output to bobbin changer
(4) SoV
MOLEX
51103-400
50351-8100
<At bobbin changer>
+5V
Photocoupler
SoV
Start prevention switch
1875M
16-3.Binding the cord
Pass the bobbin changer cord (1) under the control circuit
board and secure it using a cable tie (2).
(2)
(1)
1876M
SL-710A
99
17. SPEED SETTING METHODS
17. SPEED SETTING METHODS
17-1. Types of speed settings
Signal
Type of speed
Speed
Lo
Speed setting range
Low speed
Initial setting
150 - 300
Minimum setting
unit
220
Tt
SL
Thread trimming speed 150 - Low speed
220
Slow speed
Low speed - 1000
220
Start backtacking limit
LI (*1)
Low speed - 3000
1800
speed
Low speed - Start backtacking limit
Sb (*2)
Start backtacking speed
1800
speed
Eb
End backtacking speed Low speed – 3000
1800
H (*2)
High speed
Low speed - Limit speed
Limit speed
Au
Automatic speed
Low speed - High speed
Limit speed
Stop
improvement
Po
(Do not change.)
1500
speed
*1: The actual speed for LI is dependent on Sb.
*2: Sb (Start backtacking speed) and H (High speed) can also be set and changed using the operation panel.
10
10
100
100
100
100
100
100
100
17-2.Setting method
DANGER
Wait at least 10 minutes after turning off the power switch and disconnecting the power cord from the wall outlet
before opening the face plate of the control box. Touching areas where high voltages are present can result in
severe injury.
1. Set DIP switch 8 to ON.
2. Turn on the power switch (1).
(1)
1842M
3. Press the half stitch key (2) and the AUTO key (3)
simultaneously.
The "Lo" (Low speed) symbol will appear in LED
display AB (4).
(4)
(3)
(2)
1877M
4. Press the sewing speed key (5).
5. The "Lo" (Low speed) setting speed will appear in LED
display ABCD (4).
(4)
(5)
1878M
SL-710A
100
17. SPEED SETTING METHODS
6. Press the sewing speed key (5).
7. The "t" (Thread trimming speed) symbol will appear in
LED display AB (4).
(4)
(5)
1879M
8. In this way, the symbol and the corresponding speed
will appear in the order given in the "Types of speed
settings" table on the previous page each time the
sewing speed key (5) is pressed.
LED display
(5)
1880M
(4)
(5)
(6)
1881M
9. Press the sewing speed key (5) several times to
display the speed setting corresponding to the symbol
for the speed that you would like to set in LED display
ABCD (4).
10. Press the
and
keys (6) to change the speed
setting.
* If you would like to operate the machine at this point
to check the speed, proceed to "17-3. Checking the
speed settings".
11. When the setting is complete, turn off the power switch (1).
12. Set DIP switch 8 to OFF.
17-3.Checking the speed settings
While the setting speed is being displayed as described in
step 10 above, carry out the following operations.
1. Press the half stitch key (1).
The sewing machine will operate at the set speed.
2. Press the half stitch key (1) once more to stop the
sewing machine.
3. Return to step 10 above.
Speed setting
(1)
1882M
Note:
When checking the "H" (High speed) setting, carry out the following operations.
1. Press the half stitch key (1) to start the sewing machine at low speed.
2. Depress the treadle to the maximum.
The sewing machine will operate at the high speed that has been set.
3. Return the treadle to the neutral position. The sewing machine will decelerate to low speed.
4. Press the half stitch key (1) once more to stop the sewing machine.
5. Return to step 10 above.
SL-710A
101
18. CLEARING THE MEMORY DATA
18. CLEARING THE MEMORY DATA
Types of data that are cleared
Clearing the memory data returns all of the following data items to the factory default settings.
• Panel settings
• Memory switch settings
• Parameter settings
• Speed settings
• Lower thread counter data
Forced clearing method
While holding down the half stitch key, turn on the power.
The memory data will be cleared, and the power indicator on the operation panel will illuminate and "CL" will appear in
the LED display. After this both will start flashing. In addition, the buzzer will sound continuously.
(After this, carry out the "Confirming the clear" below.)
Automatic clearing
If the sewing machine's computer judges that the memory data is corrupted when the power is turned on, the memory
data will be cleared automatically.
In this case, the power indicator on the operation panel will illuminate and "CL" will appear in the LED display. After this
both will start flashing. In addition, the buzzer will sound continuously.
(If the sewing machine has done this, carry out the "Confirming the clear" below.)
Confirming the clear
If "CL" is flashing in the LED display of the operation panel and the buzzer is sounding continuously, press the half stitch
key. The buzzer will stop sounding and the sewing machine can then be used.
SL-710A
102
19. CHECKING THE MOTOR AND POWER SUPPLY
19. CHECKING THE MOTOR AND POWER SUPPLY
CAUTION
Turn off the power and disconnect the power plug from the wall outlet before carrying out these operations,
otherwise the sewing machine may operate if the treadle is pressed by mistake, and injury may result.
If the power switch needs to be left on when carrying out some adjustment, be extremely careful to observe all
safety precautions.
Motor connector <4P>
Power supply connector <6P>
1827M
Motor
1. Disconnect the motor connector (4P) from the control box.
2. Measure the resistance of the motor connector using
an ohmmeter in the x1 range.
If the value is as shown in the table below, the
connector is normal.
Between 2 - 3
Between 3 - 4 Approx. 2 - 3 Ω
Between 4 - 2
1883M
Power switch
1. Disconnect the power supply connector (6P) from the
control box.
2. Turn on the power switch.
3. Measure the voltage at the power supply connector
using the AC voltage range of a multimeter, and check
that the voltage is within the allowable range for the
specified voltage rating.
<100 V type (100 - 120 V)>
Measure the AC voltage between terminals 2 - 3.
<200 V type (200 - 240 V)>
[A] For three-phase
Measure the AC voltage between terminals 4 5, 5 - 6 and 6 - 4.
[B] For single-phase
Measure the AC voltage between terminals 4 6.
<100 V type>
Ground wire
<200 V type>
1884M
SL-710A
103
20. CHECKING THE SOLENOIDS
20. CHECKING THE SOLENOIDS
DANGER
Wait at least 10 minutes after turning off the power switch and disconnecting the power cord from the wall outlet
before opening the face plate of the control box. Touching areas where high voltages are present can result in
severe injury.
Control box
Lower thread detector connector <8P>
Sewing machine connector <14P>
Solenoid-type presser
lifter connector (4P)
1885M
Machine head
Sewing machine connector (14P)
Thread trimmer solenoid
Thread wiper solenoid
Quick reverse solenoid
Actuator switch
Safety switch
1886M
1. Disconnect the sewing machine connector (14P) from
the control box.
2. Measure the resistance of the sewing machine
connector using an ohmmeter in the x1 range.
If the values are as shown in the table below, the
connector is normal.
Between 3 - 4 Thread trimming solenoid: Approx. 7 Ω
Between 4 - 11 Thread wiper solenoid: Approx. 6 Ω
Between 5 - 12 Quick reverse solenoid: Approx. 7 Ω
Between 6 - 13 When actuator is pressed: Approx. 0 Ω
When actuator is released: ∞ Ω
Between 7 - 14 When machine head is upright (switch
ON): 0 Ω
When machine head is tilted back
(switch OFF): ∞ Ω
Solenoid-type presser lifter connector
Solenoid-type presser lifter connector (4P)
Knee switch
Presser lifter solenoid
1887M
1. Disconnect the solenoid-type presser lifter connector
(4P) from the control box.
2. Measure the resistance of the solenoid-type presser
lifter connector using an ohmmeter in the x1 range.
If the values are as shown in the table below, the
connector is normal.
Between 2 - 4 Presser lifter solenoid: Approx. 9 Ω
Between 1 - 3 When knee switch is pressed: Approx. 0 Ω
When knee switch is released: ∞ Ω
Lower thread detector
1. Disconnect the lower thread detector connector (8P)
from the control box.
2. Measure the resistance of the lower thread detector
connector using an ohmmeter in the x1 range.
If the value is as shown in the table below, the
connector is normal.
Between 4 - 8 Lower thread solenoid Approx. 12 Ω
Lower thread detector connector (8P)
Lower thread solenoid
1888M
SL-710A
104
21. WIRING DIAGRAMS
1889M
21. WIRING DIAGRAMS
21-1. Control circuit board assembly (1/6)
105
SL-710A
21. WIRING DIAGRAMS
1934M
Control circuit board assembly (2/6)
SL-710A
106
21. WIRING DIAGRAMS
1890M
Control circuit board assembly (3/6)
107
SL-710A
21. WIRING DIAGRAMS
1891M
Control circuit board assembly (4/6)
SL-710A
108
21. WIRING DIAGRAMS
1892M
Control circuit board assembly (5/6)
109
SL-710A
21. WIRING DIAGRAMS
1893M
Control circuit board assembly (6/6)
SL-710A
110
21. WIRING DIAGRAMS
1894M
21-2. Power supply circuit board assembly (DD7100A, 710A)
Power supply circuit board assembly (DD7100A, 710A) D-ADD1-110V (1/3)
111
SL-710A
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100A, 710A) D-ADD1-110V (2/3)
1895M
SL-710A
112
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100A, 710A) D-ADD1-110V (3/3)
113
SL-710A
1896M
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100A, 710A) D-ADD1-240V (1/3)
1897M
SL-710A
114
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100A, 710A) D-ADD1-240V (2/3)
115
SL-710A
1898M
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100A, 710A) D-ADD1-240V (3/3)
1899M
SL-710A
116
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100A, 710A) D-ADD3-220V (1/3)
117
SL-710A
1900M
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100A, 710A) D-ADD3-220V (2/3)
1901M
SL-710A
118
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100A, 710A) D-ADD3-220V (3/3)
119
SL-710A
1902M
21. WIRING DIAGRAMS
1903M
21-3. Power supply circuit board assembly (DD7100)
Power supply circuit board assembly (DD7100) D-NDD1-120V (1/3)
SL-710A
120
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100) D-NDD1-120V (2/3)
121
SL-710A
1904M
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100) D-NDD1-120V (3/3)
1905M
SL-710A
122
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100) D-NDD1-230V (1/3)
123
SL-710A
1906M
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100) D-NDD1-230V (2/3)
1907M
SL-710A
124
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100) D-NDD1-230V (3/3)
125
SL-710A
1908M
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100) D-NDD3-240V (1/3)
1909M
SL-710A
126
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100) D-NDD3-240V (2/3)
127
SL-710A
1910M
21. WIRING DIAGRAMS
Power supply circuit board assembly (DD7100) D-NDD3-240V (3/3)
1911M
SL-710A
128
21. WIRING DIAGRAMS
1912M
21-4. Transformer
129
SL-710A
21. WIRING DIAGRAMS
1913M
21-5. Operation panel B-40
Operation panel B-40 (1/3)
SL-710A
130
21. WIRING DIAGRAMS
1914M
Operation panel B-40 (2/3)
131
SL-710A
21. WIRING DIAGRAMS
1915M
Operation panel B-40 (3/3)
SL-710A
132
21. WIRING DIAGRAMS
1916M
21-6. Operation panel B-100
Operation panel B-100 (1/3)
133
SL-710A
21. WIRING DIAGRAMS
1917M
Operation panel B-100 (2/3)
SL-710A
134
21. WIRING DIAGRAMS
1918M
Operation panel B-100 (3/3)
135
SL-710A
22. TROUBLESHOOTING
22. TROUBLESHOOTING
• Please check the following points before calling for repairs or service.
• If the following suggestions do not solve the problem, turn off the machine power supply and contact your nearest
Brother service center.
DANGER
Wait at least 10 minutes after turning off the power switch and disconnecting the power cord from the wall
outlet before opening the face plate of the control box. Touching areas where high voltages are present can
result in severe injury.
CAUTION
Turn off the power switch and disconnect the power cord before carrying out troubleshooting, otherwise the
machine will operate if the treadle is pressed by mistake, which could result in injury.
22-1. Sewing
Possible cause
Problem
1. Upper thread is not • Is the upper thread tension too weak, or is the lower thread tension too
tight.
strong?
Adjust the upper thread tension or lower thread tension.
• Is the needle and feed mechanism timing correct?
Advance the needle timing.
Page
Instruction manual
67
0573M
2. Lower thread is not • Is the lower thread tension too weak, or is the upper thread tension too
tight.
strong?
Adjust the lower thread tension or upper thread tension.
Instruction manual
0574M
3. Loops appear in seam. • Is the thread path not smooth enough?
Use a file with a fine grain or sandpaper to polish smooth the thread
path.
• Is the bobbin not turning smoothly?
Pull out the lower thread to check that there is no slackness in the thread
0977M
tension, or replace the bobbin or bobbin case.
4. Skipped stitches occur • Is the needle tip bent? Is the needle tip blunt?
while sewing.
If the needle tip is bent or broken, replace the needle.
• Is the needle properly installed?
If it is incorrect, install the needle correctly.
• Is the machine properly threaded?
If it is incorrect, thread the thread correctly.
• Is the presser foot pressure too weak?
Adjust the presser foot pressure.
• Is the needle too thin?
Replace the needle with a needle that is one rank thicker.
• Is the presser foot too high?
Adjust the height of the presser foot.
• Is the needle and rotary hook timing incorrect?
Adjust the height of the needle bar.
Adjust the clearance between the needle and the rotary hook.
• Is the thread tension spring too weak?
Adjust the tension of the thread tension spring.
• Is the rotary hook tip broken?
If it is broken, replace the rotary hook.
-
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Instruction manual
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64
67
68
63
48
0470M
SL-710A
136
22. TROUBLESHOOTING
Problem
Possible cause
5. Skipped stitches at • Are the thread tension spring tensions too strong?
sewing start
Reduce the tension of the thread tension springs.
Thread unravelling at • Is the thread tension spring operating range too large?
sewing start
Lower the position of the thread tension spring.
• Are the trailing lengths of the upper threads too short after thread
trimming?
Adjust the pretension.
• Are the threads not being trimmed cleanly?
Sharpen the fixed knives, or replace the fixed and movable knives if
necessary.
• Is the needle too wide?
Try using a needle with a count that is one lower than the current needle.
• Is the length of thread trailing out from the bobbin case after thread
trimming too short?
If the bobbin is spinning loosely, replace the stopper spring in the bobbin
case.
• Is the sewing speed too fast at the sewing start?
Use the slow start feature.
• Is the needle up stop position too high?
Adjust the synchronizer.
Page
63
63
Instruction manual
Instruction manual
-
Instruction manual
70
0749M
• Is the presser foot pressure too weak?
Adjust the presser foot pressure.
• Is the feed dog too low?
Adjust the feed dog height.
• Is the bobbin scratched?
If the bobbin is damaged, smooth it with an oiled grindstone or replace it.
6. Uneven seam
Instruction manual
65
-
0473M
7. Large degree of puckering
(excess tension)
• Is the upper thread tension too strong?
Make the upper thread tension as weak as possible.
• Is the lower thread tension too strong?
Make the lower thread tension as weak as possible.
• Are the thread tension spring tensions too strong?
Make the thread tension spring tension as weak as possible.
• Is the thread tension spring operating range too large?
Lower the position of the thread tension spring to as low a position as
possible.
• Is the presser foot pressure too strong?
Adjust the presser foot pressure.
• Is the sewing speed too fast?
Reduce the sewing speed slightly.
• Is the angle of the feed dog incorrect?
Tilt the front of the feed dog down slightly.
Instruction manual
Instruction manual
63
63
Instruction manual
Instruction manual
66
0978M
8. Seam position is incorrect.
• Is the presser foot pressure too strong?
Adjust the presser foot pressure.
• Is the angle of the feed dog incorrect?
Tilt the front of the feed dog up slightly.
• Is the needle and feed mechanism timing correct?
Retard the needle timing.
0750M
SL-710A
137
Instruction manual
66
67
22. TROUBLESHOOTING
Problem
Possible cause
9. Lower thread is tangled • Is the bobbin spinning direction correct when the lower thread is being
at the sewing start.
pulled?
Spinning of bobbin
Set the bobbin so that it turns in the opposite direction to the rotary hook.
during thread trimming • Is there too much thread wound onto the bobbin?
The bobbin winding amount should not be more than 80%.
• Is the free spinning prevention spring attached?
Attach the free spinning prevention spring.
Lower
thread
• Is the bobbin turning smoothly?
If the bobbin is not turning smoothly, replace the bobbin.
• Is a bobbin other than the light-alloy bobbins specified by Brother being
0751M
used?
Use only bobbins which are specified by Brother.
Page
Instruction manual
Instruction manual
-
-
80%
0801M
10.Upper and lower • Is the needle bent or is the needle tip broken?
threads are breaking.
Replace the needle if it is bent or broken.
• Is the needle properly installed?
If it is incorrect, install the needle correctly.
• Is the needle properly threaded?
If it is incorrect, thread the needle correctly.
• Is the rotary hook sufficiently lubricated?
If the oil gauge is down to the lower reference line in the oil sight glass,
add more oil.
• Is the upper or lower thread tension too weak or too strong?
Adjust the upper thread or lower thread tension.
• Is the upper thread may be loose because the thread tension spring
operating range is too small?
Adjust the position of the thread tension spring.
• Is the rotary hook, feed dog or other part damaged?
If they are damaged, smooth them with an oiled grindstone or replace
the damaged parts.
• Is the thread path damaged?
If the thread path is damaged, smooth it with sandpaper, or replace the
damaged part.
Instruction manual
Instruction manual
59
Instruction manual
63
48, 49
-
0471M
11. Incorrect thread trimming. • Is the fixed knife or movable knife damaged or worm?
(upper and lower
Replace the fixed knife or the movable knife.
threads are both not • Is the fixed knife and movable knife meshing amount correct?
being trimmed).
Adjust the fixed knife and movable knife meshing amount.
• Is the movable knife operating correctly?
Measure the resistance between terminals 3-4 of the sewing machine
connector with an ohmmeter. If the measured value is not normal,
replace the thread trimmer solenoid.
12. Incorrect thread trimming. • Is the needle properly installed?
(upper thread or
If it is incorrect, install the needle correctly.
lower thread is not • Is the fixed knife or movable knife blunt?
being trimmed).
Replace the fixed knife or the movable knife.
• Is the fixed knife and movable knife meshing amount correct?
Adjust the fixed knife and movable knife meshing amount.
SL-710A
Instruction manual
47
104
Instruction manual
Instruction manual
47
138
22. TROUBLESHOOTING
Problem
Possible cause
13. Movable knife does • Is the resistance between terminals 3 - 4 of the sewing machine
not operate.
connector normal?
Measure the resistance between terminals 3 - 4 of the sewing machine
connector with an ohmmeter. If the measured value is not normal,
replace the thread trimmer solenoid.
• Is the sewing machine connector
disconnected from the control
circuit board? Or, is the thread
trimmer
solenoid
cord
disconnected from the sewing
machine connector?
If the sewing machine connector
is connected correctly, there may
be a problem with the control
circuit board. Contact the place
0987M
of purchase.
14. Broken needle
• Is the material being pushed or pulled with excessive force during
sewing?
• Is the needle properly installed?
If it is incorrect, install the needle correctly.
• Is the needle bent, is the needle tip broken, or is the needle hole
blocked?
Replace the needle.
• Is the needle and rotary hook timing incorrect?
Adjust the height of the needle bar.
Adjust the clearance between the needle and the rotary hook.
• Is the needle timing advanced too far with respect to the feed dog?
Retard the needle timing.
Page
104
58
Instruction manual
67
68
67
Caution
• It is extremely dangerous to leave any pieces of broken needle
sticking in the material. If the needle breaks, search for all pieces until
the whole of the needle is found again.
• Furthermore, we recommend that through steps be taken to account
for such needles to comply with product liability regulations.
0469M
15. The stitch lengths in the • Is the eccentric pin adjusted properly?
normal feed direction
Adjust the eccentric pin.
and reverse feed
direction are not equal.
69
16. An impact noise is • Is the quick reverse solenoid clearance correct?
heard from the quick
Adjust the position of the solenoid lever.
reverse solenoid.
52
17.Oil gauge is not visible • Is the oil tank empty?
in oil sight glass.
Fill the oil tank with oil.
• Is the rotary hook lubrication adjusting screw too loose?
Check the rotary hook lubrication amount, and adjust the rotary hook
lubrication adjusting screw.
• Is the oil gauge damaged?
Replace the oil gauge.
Oil gauge
0979M
SL-710A
139
59
73
42
22. TROUBLESHOOTING
Problem
18.Machine does not
operate when power is
turned on and treadle
is pressed.
1) Operating panel power
indicator does not
illuminate.
Possible cause
• Is the power supply connector
disconnected from the control
box?
Insert the connector securely.
Page
Instruction manual
1002M
• Is the power supply plug incorrectly wired or is the voltage incorrect?
Check the power plug wiring and the power supply voltage. (Try
inserting into a different wall socket.)
2) Only operating panel • Is DIP switch No.8 inside the
power
indicator
control box set to ON?
illuminates.
Set DIP switch No.8 to OFF.
-
81
1003M
1001M
3) Operation panel operates • Is the treadle unit connector
normally.
inside
the
control
box
disconnected?
Securely connect the connector.
96
0998M
• Has the treadle unit or control circuit board been replaced?
Adjust the depression stroke to the standard setting.
• Is operation possible using the standing operation pedal?
If operation is not possible, turn the power off and then back on again.
19. Machine does not
operate at high speed.
• Is the sewing speed setting or backtack speed setting incorrect?
Set the speed to a higher speed using the operating panel.
• Is the FVR inside the control box
at the maximum setting?
Turn the FVR clockwise to the
maximum setting.
• Treadle unit signal abnormality.
Adjust the depression stroke to the standard setting.
92
Instruction manual
80
1920M
92
20. Thread is trimmed • Treadle unit signal abnormality.
when treadle
is
Adjust the depression stroke to the standard setting.
returned
to
the
neutral position.
• Is the FVR inside the control box
21. Startup is slow.
at the maximum setting?
Turn the FVR clockwise to the
maximum setting.
92
80
1920M
SL-710A
140
22. TROUBLESHOOTING
Problem
Possible cause
22.Sewing machine starts • Is DIP switch 2 inside the control
operating
before
box set to OFF?
presser foot is lowered
Set DIP switch 2 to ON.
(solenoid-type presser
lifter specifications).
Page
81
1921M
23. Presser foot does • Is the solenoid-type presser lifter
not lower (solenoid1P connector also connected?
type presser lifter
If not using the 1P connector,
specifications).
disconnect it.
• Treadle unit signal abnormality.
Adjust the depression stroke to the standard setting.
-
1922M
92
24. Machine stops during • Is the power supply voltage too low?
sewing.
Check the power supply.
(If the power cord is too long or too many appliances are being run from
a single outlet, this may cause voltage drops which will in turn cause the
reset function to activate and stop the machine, even if the power supply
itself is normal.)
25. Lower thread detector
does not operate.
• Is the lower thread detector
connector inside the control box
disconnected?
Insert the connector securely.
• Is the lower thread detector relay
cord inside the machine head
disconnected?
Securely connect the cord.
Instruction manual
0993M
-
• Is memory switch No. 16 set to ON?
Set memory switch No. 16 to OFF.
0994M
26. None of the solenoids • Is the 8 A fuse inside the control
operate.
box blown?
If the 8 A fuse is blown, check
the resistances of all the
solenoids, and replace any
solenoid that has an abnormal
resistance.
After this, replace the 8 A fuse.
SL-710A
87
104
1923M
141
103
22. TROUBLESHOOTING
Problem
Possible cause
27. The thread trimmer and • Is memory switch No. 11 set to ON?
thread wiper solenoids
Set memory switch No. 11 to OFF.
do not operate.
• Are the solenoid resistances normal?
If the resistances are not normal, replace the solenoids.
• Is the 8 A fuse inside the control box
blown?
If the 8 A fuse is blown, check
the resistances of all the
solenoids, and replace any
solenoid that has an abnormal
resistance.
After this, replace the 8 A fuse.
Page
87
104
104
1919M
28. Motor does not operate • Problem with speed sensor.
smoothly, or motor
Replace the motor.
makes
noise.
an
29. Fluorescent
flickers.
34
abnormal
lamp • This can occur if the power supply capacity is not sufficient.
Adjust the FVR inside the control box.
The flicker is reduced when the FVR is turned to the left.
(The sewing machine start-up also becomes slower when this is done.)
30. The illumination lamp • Is the lamp blown?
does not turn on.
Replace the lamp (6 V).
• Is the 5 A fuse inside the control
box blown?
Replace the 5 A fuse.
• Is the lamp cord disconnected
from the terminal board inside
the control box?
Securely connect the cord.
• Is the CN9 connector inside the
control box disconnected?
Securely connect the connector.
80
-
80
80
5 A fuse
Terminal
board
CN9
80
1924M
31. Stitch number display • Problem with control box.
on operation panel is
Replace the control box.
flashing.
32. Some other operating • Clear the memory data. The settings will be returned to their factory
problem is found.
defaults.
• Adjust the depression stroke to the standard setting.
SL-710A
76
102
92
142
22. TROUBLESHOOTING
22-2. Error code displays
If an error code is flashing on the operation panel display
Error code
Possible cause
• Is the bobbin changer power
switch turned on?
Turn on the bobbin changer
power switch.
bo
Page
-
0996M
0995M
dp
(DD7100A, 710A only)
• Is a standby signal still being input from the bobbin changer?
Check the bobbin changer.
-
• Is DIP switch 8 inside the control
box set to ON?
Set DIP switch 8 to OFF.
1925M
81
1003M
• Malfunction of speed sensor, or open circuit in cord.
Replace the motor.
Ec
34
0999M
• Has the setting for standard depression strokes been set correctly?
Repeat the setting for standard depression strokes.
• Treadle unit malfunction.
Replace the treadle unit.
Er
92
96
1000M
• Is the motor connector inside the
control box disconnected?
Insert the connector securely.
L
0988M
O
0989M
• Has the machine locked up?
Turn off the power and then turn the machine pulley by hand and check
that it turns easily.
-
• Was a key other than the half stitch key on the operation panel still on
when the power was turned on?
Take your hand off the operation panel and turn the power switch on.
• Problem with operation panel.
Replace the operation panel.
-
1926M
SL-710A
143
Instruction manual
55
22. TROUBLESHOOTING
Error code
Possible cause
• Is the machine connector inside
the control box disconnected?
Insert the connector securely.
oF
0986M
• Is the machine head tilted back?
Return the machine head to its
normal position.
Check the operation of the safety switch.
Page
Instruction manual
0987M
• This appears on the display when the sewing machine has been
operating continuously for 3 minutes or more.
Turn the power switch off and then back on again, and then operate the
sewing machine normally.
ot
62, 104
-
0991M
• Is the power supply voltage abnormally
high?
Check that the power supply voltage
matches the control box voltage
specifications.
ou
0980M
Voltage rating label
77
0981M
• Is connector CN7 or CN8 inside
the control box disconnected?
Securely connect the connectors.
• Problem with control box.
Replace the control box.
P
1927M
80
76
1928M
• Is the treadle unit connector
inside
the
control
box
disconnected?
Insert the connector securely.
PE
0997M
• Treadle unit malfunction.
Replace the treadle unit.
96
0998M
• Is the power supply voltage too low?
Check the power supply voltage.
• Was the power turned on while the treadle was still depressed?
Return the treadle to the neutral position, and then turn on the power
switch.
rE
96
103
-
0990M
SL-710A
144
22. TROUBLESHOOTING
Error code
Possible cause
• Is the synchronizer connector inside
the control box disconnected?
Insert the connector securely.
U
Page
80
• Problem with synchronizer.
Replace the motor.
34
0982M
1929M
• Is detector pin (1) of the bobbin
thread detector not retracted
correctly?
Retract the detector pin (1).
Use an Allen key to move the
slider (2), and check that the
detector pin (1) moves correctly.
UE
(1)
(2)
Instruction manual
• Problem with lower thread detector.
Replace the lower thread detector.
0985M
0984M
• Is the lower thread detector
connector inside the control box
disconnected?
Insert the connector securely.
Uo
Instruction manual
0993M
80
• Is there an open circuit in the
lower thread detector connecting
cord inside the machine head?
Replace the lower thread detector
or the connecting cord.
0994M
0992M
SL-710A
145
SERVICE MANUAL
15-1, Naeshiro-cho, Mizuho-ku, Nagoya 467-8561, Japan. Phone: 81-52-824-2177
Printed in Japan
117-S11
I2010820H
2002.09. H (1)