Automatic threading video recorder

Automatic threading video recorder
United States Patent
[151
3,697,679
[451 Oct. 10,1972
Hathaway
1541
AUTOMATIC THREADING VIDEO
' RECORDER
[72] Inventor: Richard Allen Hathaway, Saratoga,
Calif.
[73] Assignee: Ampex Corporation, Redwood City,
3,208,682
9/1965
Pastor ...................... ..242/195
3,190,575
3,550,983
6/1965
12/1970
Hayner .................... ..242/195
Probst ............... ..179/1002 Z
Primary Examiner-Howard W. Britton
Attorney—-Fitch, Even, Tabin & Luedeka and Robert
G. Clay
Calif.
[22] Filed:
July 1, 1970
[21] Appl. No.: 51,447
[5 7]
ABSTRACT
A video tape is automatically threaded from a supply
means such as a tape cartridge or cassette about a
[52]
[51]
[58]
U.S. Cl. ........ ..l78/6.6 A, 179/1002 Z, 242/192
Int. Cl. ..... ..G03b 1/58, G1 lb 15/66, H04n 5/78
Field of Search ........... ..178/6.6 A; 179/1002 Z;
242/192, 195
[56]
References Cited
UNITED STATES PATENTS
3,312,407
3,160,704
4/1967
Goldberg ................. ..242/195
12/ 1 964
Hollingsworth ....... .. 1 78/66 A
video scanner and past appropriate sound, control
track and erase heads to a take up means. Preferably,
a stripping means is effective to strip a leader from a
tape cartridge having coiled video tape therein and
feed the leader to the take up means. The video tape
attached to the leader is preferably threaded at opera
tional speed and with operational tension by a tape
capstan and pressure roller means which is automati
cally disabled when the video tape is threaded.
13 Claims, 6 Drawing Figures
3.697.679
PATENTEDnm 10 I972
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3.697.679 ‘
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INVENTOE
1
3,697,679
2
AUTOMATIC THREADING VIDEO RECORDER
23 in the cartridge for facilitating an automatic start of
threading.
This invention relates generally to machines such as
video tape recorders for recording on or playing back
from a video tape contained in a roll in a cartridge and
In accordance with the present invention, the tape
leader 21 is automatically pulled from the cartridge 17
and fed forwardly for threading along a path of travel
more particularly to an apparatus in a video tape
recorder for threading the video tape from the car
through a standard arrangement of video tape recorder
tridge through instrumentalities and to a takeup reel in
components, including a video erase head 27, a scanner
assembly 29, a combined audio, audio erase and con
trol track head means 31 and a capstan tape drive
means 33 to a take-up supply station 35 at which is
the video recorder.
'
The usual manner of threading a video tape recorder
is to pull a length of tape from a roll of tape on a supply
reel and manually thread the leading tape end about a
scanner assembly which requires forming an arcuate
located a tape take-up reel 37. As will be explained, the
tape leader is fed forwardly to thread the tape by a
threading drive means 38 (FIG. 4) into the capstan
tape drive means 33, which then may control the speed
loop in the video tape, and then threading the tape
through a capstan tape drive and through suitable
audio and erase heads before attaching the leading end
of the tape to the take-up reel. This manual operation
and feed of the tape as it is threaded to assure that the
tape is fed at the desired speed and with the desired
tension in the tape. Preferably, the threading tape drive
means 38 is automatically disabled when the capstan
necessitates that the user understand the proper thread
path for the tape; and moreover, requires a considera
ble handling and manipulation of the tape and access to
drive means 33 is enabled so that tape is driven at
the interior of the recorder which is best kept covered 20 operational speed for winding on the take-up reel.
and protected from dust, damage or dirt. Such con
Referring now in greater detail to the individual ele
siderations are particularly pertinent to video tape
ments, the illustrated tape cartridge 17 is provided with
recorders for home use where relatively unskilled users
means to retain the leading end 22 of the tape leader 21
may improperly thread the tape or permit damage to 25 to the cartridge 17 so that the same will not fall or un
the internal components of the tape recorder. Thus, it
is desirable to provide an automatic and self-threading
capability for a video tape recorder to assure easy and
coil from the cartridge as the same is handled, shaken,
vibrated or otherwise manipulated prior to or after use
with the video tape recorder 11. The preferred manner
of retaining the leader at the tape cartridge is to enlarge
proper tape threading. However, the self-threading ap
paratus is difficult to achieve while still retaining a stan 30 the leading end to a width dimension, which is wider
dard layout of video tape recorder components such as
than the usual V2 inch width for the remainder of the
the scanner assembly, tape-driving assembly capstan,
leader and for the conventional standard video tape,
and to insert the widened, leading end 22 into recesses
sound and video head assemblies and proper tension in
the video tape. Additionally, the tape recorder should
or slots 41 formed in the outer edges 43 of upper and
thread a standard size of video tape and also operate at 35 lower reel ?anges on opposite sides of the slot 23
the conventional speed.
Accordingly, an object of the invention is to provide
an automatic self-threading capability for a video tape
machine of the foregoing kind.
Other objects and advantages of the invention will
become apparent from the following detailed descrip
40
through which the tape may exit the cartridge. The
leading end 22 is thus held against unwinding or being
expelled from the cartridge when manually shaken dur
ing handling or shipping. As best seen in FIG. 1, the tip
of the tape leader projects outwardly from the edges of
cartridge walls 43 for peeling from the slots 41.
tion taken in connection with the accompanying
Preferably, the supply cartridge has a center reel hub
drawings, in which:
opening 47, which telescopingly receives a spindle 49
FIG. 1 is a top view of a video tape cartridge;
of the video tape recorder when the cartridge is placed
FIG. 2 is a fragmentary, partially sectioned view of a 45 on a turntable (not shown) at this supply station 13.
tape leader and means to secure it to the cartridge;
Handling of the tape and leader 21 and an initial
FIG. 3 is a top view of an automatic threading video
manual threading start of the tape are avoided by auto
tape recorder embodying the novel features of the in
matically peeling the leading end 22 from the retaining
vention;
slots 41. That is to say, there is no need for an initial
FIG. 4 is a diagrammatic, enlarged view of the self 50 manual manipulation of the leader to remove the lead
threading mechanism for the video tape recorder of
ing end 22 from the cartridge and to insert the same
FIG. 3;
into the threading drive means 38. The means for peel
FIG. 5 illustrates winding of the video tape in a
ing the leading end 22 is in the form of a pointed ?nger
reverse direction from the winding direction of FIG. 4;
51 of generally triangular crosssection which is
55
and
mounted on a pivot post 52 for pivoting to bring a knife
FIG. 6 illustrates another embodiment of the inven~
like edge 53 thereon from a spaced inoperative position
tion.
from the cartridge 17 and leader 21 to an operative
As shown in the drawings for the purpose of illustra
peeling position adjacent to the outer pheripheral wall
tion, the invention is embodied in a video tape recorder
43 of the tape cartridge to engage the leading end 22 of
11, which has a tape supply station 13 at which is 60 the leader 21. When the tape cartridge beings its initial
located a supply reel drive means which accepts and
rotation in the unwinding direction, which is a counter~
supports a self-contained tape cartridge 17 within _ clockwise direction, when viewed as in FIG. 4, the edge
which is a coil 18 of video tape 19. Attached and
53 of the peeling ?nger engages the under side of the
disposed about to the outer coil of the video tape is a
65 leader and as the cartridge continues to turn the leader
tape leader 21 which is of a sti?er material than the
21 moves forwardly across the upper side of the finger
tape. A leading end or portion 22 of the tape leader is
and to the threading drive means 38 which is closely
supported by the tape cartridge and projects from a slot >
located adjacent to the peeling ?nger.
3
3,697,679
The self-threading operation may be instituted by
depression of a thread push button 55 on a control
panel of the video tape recorder 1 l, as best seen in FIG.
3, which causes the supply cartridge 17 to turn and the
4
jacent the outlet end of the scanner guide 73. Closely
adjacent but spaced from the ?xed guide chute 85 is an
exit edge guide 87 about which the tape will be guided.
A vertical edge guide 88 in the form of ' a roller is
peeling ?nger 51 to pivot to a position to peel the pro
spaced from the concave surface 84 of the ?xed guide
jecting end 22 of the tape leader from the tape car
tridge and start the same to move forwardly. The push
chute 85 and the leader will move through the gap
therebetween. As the leading end of the leader exits the
button accomplishes the foregoing by completing a cir
concave surface 84 of the ?xed guide chute 85, it
cuit to energize a solenoid 57, as best seen in FIG. 4,
moves into a space between an audio, erase and control
which has a plunger 59 connected to a rotatable idler l0 track, head means 31, which are located in a single
61 by a link means to move the idler into contact with
stanchion and a thread guide 89 which is spaced from
an annular drive surface 63 on a turntable which sup
and is disposed on the opposite side of the leader from
ports and carries the tape cartridge 17. The idler 61 is
this stanchion. The pusher roller 67 continues to push
pulled by the solenoid 57 into frictlonal engagement
with and is driven by a push roller 67 which is con
nected to a motor (not shown) and supplies the driving
power for turning the tape cartridge turntable. The
the leader 21 and its leading end 22 forwardly from this
stanchion to the capstan drive means 33 and more
speci?cally into a gap 91 between a tape feed capstan
93 and a cooperating pinch roller 95. At this time, the
pinch roller 95 may be spaced from the capstan 93 by a
shifting from a position spaced from the path of travel
20 distance greater than thickness of the tape leader so
for the leader and tape with operation of the solenoid
that the leading end 22 passes quickly through the gap
57 to a position in which it establishes a feeding nip
91 therebetween and forwardly to a sensing means 96
with a pinch roller 69 which is disposed on the opposite
which detects that the leading end 22 has progressed
side of the leader or tape. Thus, during the initial rota
through the capstan drive means 33. Alternatively, the
tion of the tape cartridge, the leading end of the leader 25 pinch roller 95 and capstan 93 may be engaged before
is peeled from the slot and is guided into the nip
entry of the leading end of the leader. At the time that
between the pusher roller 67 and the pinch roller 69,
the leading end 22 of the leader is sensed by the sensing
which then begin to push the leader forward.
means 96, the leader 21 extends for about 2 feet
The leader 2]. is preferably of such a stiffness that it
will be self supporting in comparison to the relatively 30 through the various assemblies of the video tape
recorder and back through the nip of the thread driving
limp video tape 19 to which it is attached and yet suffi
means at the push roller 67.
ciently ?exible to be guided for travel along curved
The preferred manner of assuring that the video tape
paths particularly about the scanner assembly 29. The
is
threaded
through the machine at the usual operating
preferred leader is about two feet in length in order that
speed
and
with
the normal amount of tension needed
it may extend from the pusher roller 67 all the way to 35
for
operation
is
to have the sensing means 96 disable
the tape capstan drive means 33 during the threading
the
push
drive
initial
threading means 38 and to enable
operation. This length has been found to be suf?cient
‘the
capstan
drive
means
33 for pulling the video tape
to extend the full tape about the video erase head 27,
from
the
tape
reel
and
moving
the same through the
scanner assembly 29, and other audio, erase and track
scanner assembly and past the respective heads of the
heads 31 when the latter are positioned in accordance
video tape recorder. More speci?cally, the sensing
with the conventional arrangement for video tape
push roller 67 is also mounted on a lever means for
recorders.
means 96, which is in the form of a photocell 97 and a
light source 98 disposed on opposite sides of the leader
21 and tape travel path, sense the leading end 22 of the
receive the leading end 22 of the leader 21 as the latter 45 leader 21 and operating relay (not shown) to open the
circuit for the solenoid 57 whereby the solenoid
exits from the nip between the push roller 67 and pinch
The video erase head 27 is disposed immediately
downstream of the push roller 67 and pinch roller 69 to
roller 69. When leaving the push and pinch rollers, the
leading end 22 is generally aligned with a slot formed
between a stationary guide chute 71 and the video
plunger 59 is returned by a spring (not shown) to shift
the link means to move the idle roller 61 to its position
spaced from the turntable surface 63 (as shown in
erase head 27, the leader exits the video erase head 50 dotted lines FIG. 4). Also, the return of the solenoid
past ?xed edge guide 74 and is aligned to insert into a
gap 72 formed between a curved guide 73 and a cylin
drical surface 77 of a scanner disk of the scanner as
sembly 29. Another guide 75 may be placed adjacent
the scanner cylindrical surface and spaced up-stream
from the inlet end of the curved guide 73 to assure that
the leading end enters a throat between the scanner
plunger 59 swings the push roller 67 from the leader to
a position in which it is spaced from the pinch roller 69
sufficiently that it will not feed the leader or the tape
19. The sensing means also energizes solenoid 99 to
55 move its plunger 101 to shift the pinch roller 95 toward
the tape and into operative position with the capstan 93
so that the leader is now being pulled forwardly by the
capstan drive means 33 at the usual operational speed,
and the curved guide. Within the scanner assembly, is
e.g. 71/2 ips.
the conventional scanning bar 79 containing two video
heads 81. Preferably, the scanner guide 73 is substan 60 As the leading end of the leader is fed forwardly by
the tape capstan drive means 33, it passes a roller guide
tially continuous and guides through an arcuate path
107 and moves into engagement with a ?rst, pivotally
’ about the scanner surface 77 until the leader exits at an
outlet end 83 of the curved guide 73.
mounted arcuate guide follower 109 at the take-up reel
As the leading end 22 of the leader 21 exits the outlet 65 station 35 and is guided partially about the reel hub
end 83 of the curved guide 73 for the scanner assembly
into engagement with a second guide follower l 11. The
29, it abuts and slides alonga concave surface 84 of a
guide followers 109 and 111 are substantially identi
?xed guide chute 85 which has edge 86 closely ad
cally in construction and include a curved member 1 12
5
3,697,679
pivotally mounted on a pivot post 113 and urged by a
spring 115 against a friction surface such as rubber or
vinyl on a cylindrical, peripheral surface of a hub 117
of the take up reel 37. The spring biased follower 111
holds the leading end of the leader with sufficient force
against the frictional surface on the hub 117 that the
leader moves therewith and wraps thereon. The take up
reel hub 117 is driven at operational speed to wind the
leader and to take up tape from the capstan drive
means.
It is preferred that a time delay (not shown) be pro
vided to de-energize the solenoid 99 to retract the
pinch roller 95 and to disable the motor drive of take
up hub 117 after a time sufficient to assure that the 2
feet of leader is wrapped on the take up reel and the
6
leaving scanner surface 77 and the outlet end 83 of the
tape guide 73 passes between the roller 88a and the
?xed edge guide 85 and past the sound head means 31a
and tape capstan drive means 33a to the upper and left
quadrant of the take up reel 37a for being wound in a
clockwise direction about the take up reel hub 1 170.
With an arrangement of heads, guides, scanner as
sembly similar to that heretofore described in connec
tion with FIG. 4, the tape take up means may be posi
tioned to conserve space by shortening the distance
between centers for the tape cartn'dge l17b and the
take up reel 37b. A suffix “b” has been added to
reference characters previously used to identify and
describe similar elements in the above speci?cations.
More speci?cally, a supply tape cartridge 17b may be
video tape is in operational position. Thus, the tape
placed on and removed from a spindle 49 on a turnta
transport is automatically terminated at the end of the
threading operation and the unit is ready for a sub
sequent operation of a play or record push button
operation to commence recording or playback.
In the preferred embodiment of the invention the
inner end of tape 19 coiled within the tape cartridge is
fastened by a length of material similar to the leader
tending into large arcuate cutouts 133 in take up reel
outer ?anges 131. The cutouts 133 allow the supply
cartridge 17b to be inserted or moved from the supply
turntable without interference. The take up reel outer
ble at the supply station with its ?anges 44 and 45 ex
?anges 131 may be ?xed to and suitably supported by
the video tape recorder frame. At the center portion of
material to a central hub 120 of the supply cartridge. 25 the take up reel 37b are small inner reel ?anges 135
When the video tape 19 has been stripped and uncoiled
which are attached to the take up reel hub 117 b for
from the cartridge, an additional pulling of the tape 19
rotation with the hub. The small reel ?anges are about
by the tape capstan drive means 93 applies sufficient
‘A inch larger in diameter than the take up reel hub
torque to a tape tension arm 121 to swing it counter
1 17b to center and support the initially wound turns of
clockwise as viewed in FIG. 4 to operate a switch 123 30 the leader and tape. The smaller reel ?anges rotate
which will indicate the end of the tape. Preferably, the
within a circular opening 137 in the ?xed ?anges and as
tape tension arm 121 is pivotally mounted on a pivot
the diameter of the tape roll 18b becomes larger, the
post 124 and is formed with an arm 125 on a free end of
outer turns of video tape will progress outwardly into
which is joumaled a roller for engaging the inner side of
the space between the fixed outer ?anges 133 and then
the video tape and exerting an outward tension or pull 35 across a gap 139 to the supply cartridge and into space
on the tape. The stripping ?nger 51 may also be
between the ?anges 44b and 45b of supply reel car
mounted on the tape hold back tension arm 125 if so
tridge 17b. The distance saved by moving the reel cen
desired.
ters toward on another is represented by the shaded
As an alternative to the use of the time delay relay
area in FIG. 5, which indicates the proportional
for disabling the tape capstan drive means 33 at the end
amount of overlays available when the tape is ?rst all
of the tape threading operation, it may be desired to
on the supply cartridge and then wound all on the take
utilize a clear transparent plastic material for the leader
up reel.
21 and to continue the feeding of the tape and leader
From the foregoing it was seen that there is provided
until the opaque video tape is sensed by the photocell 45 a convenient and reliable method of obtaining a self
sensing means 96 at which time the tape capstan means
threading of a reel of tape about scanner heads and
33 may be disabled. Thus, the tape will be threaded and
guides, etc., and on to the take up reel. The self-con
the apparatus made ready for a subsequent play or
tained cartridge having a leader provides a simple and
record mode of operation when the sensing means 95
reliable manner for automatically threading the tape
stops the tape movement.
through the video tape recorder prior to initiation of a
As will be understood by those skilled in the art, in
play record function. The usual standard layout of
the above described embodiment of the invention the
components such as the scanner heads, guides and take
video tape was described as being threaded and
up reel may be retained. The device is particularly ef
wrapped on the take-up hub 117 in a so-called “A”
fective in obtaining the proper tension in tape and to
wrap with the oxide layer in when wound on the take 55 automatically suspend tape feeding after the tape has
up hub 117 turning a counterclock-wise direction as
viewed in FIG. 4. On the other hand, the oxide layer of
been properly threaded.
Iclaim:
the video tape may be wrapped on the take up hub with
1. In a video tape recorder, an apparatus for auto
the oxide layer facing out by wrapping the video tape in
matically threading a tape from a supply cartridge hav
a clockwise direction on a take up hub in a so-called 60 ing a roll of video tape which has a leader affixed to the
“B” wrap. When it is desired to provide a “B" wrap,
the audio erase and sound head means 31a, capstan
drive means 33a and sensing means 95a along with the
leading end of the tape, said apparatus comprising sup
port means for supporting said supply cartridge, a take
up means spaced from said support means and having
tape guides are placed in the positions shown in FIG. 6
means
for winding said video tape thereon, a video
65
in which common reference characters with the suffix
scanner assembly including a rotatable scanning disk
“a” are used to designate components similar to those
having an outer circular peripheral surface spaced from
described hereinbefore. Thus, the tape or leader 21
said support means and mounted for operative associa
7
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8
tion with saidvideo tape transported from said car
7. A video recorder in accordance with claim 6 in
which said sensing means includes a photosensitive
tridge, sound recording and reproducing transducer
means for operative cooperation with said video tape at
system for detecting a change in light characteristics
with movement of said tape and leader therepast.
8. A video tape recorder in accordance with claim 6
positions along said path of tape transport intermediate
said support means and take-up means; means for in
itiating movement of said video tape leader forwardly
from said cartridge and along the path of tape move
in which said sensing means senses said leader and said
tape and disables said video tape drive means and said
take-up means after a predetemiined period of time.
ment; feed means downstream from said supply car
tridge support means having a leader feed nip for feed
9. In a video tape recorder for playing back from or
ing said leader forwardly and about said rotatable disk 10 recording on a video tape wound in a coil in a supply
of said video scanner assembly and past said sound
cartridge and having a leader secured to the leading
recording and reproducing means; ?rst guide means in I end of the video tape, the combination comprising sup
termediate said supply cartridge and said rotatable cir
port means for supporting said cartridge as said video
cular scanning disk for guiding said leader to adjacent
tape is unwound from said coil, a take-up means for
said outer circular peripheral surface of said scanning 15 winding said leader and tape into a coil, leader trans
disk, arcuate guide means extending about a substantial
porting means downstream from said support means
peripheral portion of said circular disk to guide said
for transporting said leader along a predetermined path
leader in an arcuate path of substantial length about
from said cartridge to said takeup means, a scanner as
said circular scanning disk, said ?rst guide means
sembly downstream of said support means and having a
directing said leader in a ?rst direction and said arcuate
rotatable scanning disk with a circular, peripheral sur
guide means directing said leader to depart from said
face for contacting said video tape, ?rst guide means
?rst direction through a substantial angular change of
intermediate said supply cartridge and said rotatable
direction, means guiding said video tape for an arcuate
circular scanning disk for guiding said leader to ad
wrap of substantial length about said rotatable circular 25 jacent said outer circular peripheral surface of said
scanning disk, exit guide means for guiding said tape
scanning disk, arcuate guide means extending about a
leader exiting from said scanning disk past said sound
substantial peripheral portion of said circular disk to
recording and reproducing means to said take-up reel
guide said leader in an arcuate path of substantial
means, video tape drive means for driving said video
length about said circular scanning disk, said ?rst guide
tape at operational speed and with a predetermined 30 means directing said leader in a ?rst direction and said
tension in said video tape to establish the tension in said
arcuate guide means directing said leader to depart
video tape for a subsequent video recording or
from said ?rst direction through a substantial angular
reproducing operation, and means for disabling said
change of direction, means for guiding said video tape
leader feed nip of said feed means as said video tape is
for an arcuate wrap of at least 180° about said rotatable
being driven by said tape drive means and being wound 35 circular scanning disk, exit guide means for guiding
on said take-up means.
said tape leader exiting from said scanning disk past an
2. A video recorder in accordance with claim 1 in
audio recording and reproducing means to said take-up
which said feed means includes a push roller which is
reel means, means including audio, audio erase, and
driven and a guide roller; said push roller and guide
track heads located downstream of said video scanner
roller being disposed on opposite sides of said leader 40 for operative association with said video tape, a capstan
and movable from and to gripping relationship with
tape feeding means for feeding the tape operational
said video tape.
'
speeds, and means for guiding said leader to said take
3. A video recorder in accordance with claim 1 in
up means and for attachment thereto so that said leader
which said vfeed means comprises a push roller and a
may be wrapped on said take-up means.
guide roller, said push roller and guide roller being 45 10. A video tape recorder in accordance with claim 9
disposed on opposite sides of said leader, in which said
in which said means for transporting said leader in
cartridge support means includes a turntable and in
cludes a feed means for feeding said leader forwardly
which a means is engageable with said turntable and
past said scanner assembly, said audio head, said audio
said push roller to turn said turntable with driving of
erase head, and said track heads and further includes a
50 video tape drive means for driving said leader to said
said tape.
'
4. A video recorder in accordance with claim 1 in
' take-up means and for driving said video tape at opera
which said video tape has an oxide surface coating and
tional speed and with a predetermined tension in the
in which guide means are provided on the exit side of
said scanner assembly to wrap said tape with said oxide
video tape.
coating facing inwardly when coiled on said take up
10 in which means are provided to disable said feed
means when said leader reaches said video tape drive
means.
5. A video recorder in accordance with claim 1 in ‘
.
, 11. A video tape recorder in accordance with claim
-
means.
which said video tape has an oxide surface coating and
" 12. A video tape recorder in accordance with claim
in which guide means are provided on the exit side of
10
in which said cartridge is separate and separable
said scanner assembly to wrap said video tape with said 60 from a take-up reel for said take-up means, said tape
oxide coating facing outwardly when coiled on said
being wound'about ?rst and second axes which are
take up means.v
spaced from each other by a distance which is less than
6. A video tape‘ recorder in accordance with claim 1
twice the radius of a fully wound coil of tape in said
in which said means for disabling said feed means in
supply
cartridge.
65
cludes sensing means for sensing the position of said
13. A video tape recorder in accordance with claim
tape at a predetermined position along said path of
12 in which said take up means includes a stationary
travel.
cover having a portion on a side facing said supply por
3,697,679
9
10.
tion cut out to accommodate a portion of said supply
cartridge whereby when said tape from said supply car
tridge is fully wound in a coil on said take up means a
portion of said coil may project into said supply car
tridge.
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