F/G.4.
Mardh 31, 1970
Filed Ju?y 26, 1965
`F? v. BELLIS s
`
3,504,133
INDEXING MEANS FOR MULTI-TRACK MAGNETIC
'I'APE REPRODUCING APPARATUS
2 Sheets-Sheet 1
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F/G.4.
37
Mardh 31, 1970
Filed July 26, 1965
.
F. V. BELLlS
3,504,133
`
INDBXING MEANS FOR MULTI-TRACK MAGNETIG
TAPE REPRODUCING APPARATUS
2 Sheets-Sheet 2
“WN
i
F/G. 2. `
%unit/Mick. V- Edhè,
INV EN'TOE
BY
mâm_
United States Patent Office
3,504,l33
Patented Mar. 31,- 1970
l
2
3,504,133
at a spooling speed substantially higher than said ?rst
speed; a mount for said head comprising track selection
INDEXING MEANS FOR MULTI-TRACK MAG
NETIC TAPE REPRODUCING APPARATUS
means for providing controlled movement of said head
in a direction transverse to said path for selection of one
Frederick Victor Bellis, Carshalton Beeches, England,
assignor to Clarke & Smith Manufacturing Company
track from said plurality and comprising a manually op
erable member for displacing the head in said direction
to a position for alternatively selecting an indexing track,
,and guide means for guiding movement of the head in
said direction.
Limited
Filed July 26, 1965, Ser. No. 474,623
Claims priority, application Great Britain, July 24, 1964,
29,794/ 64
Ir?t. Cl. Gllb 5/ 02
U.S. Cl. 179-100.2
4 Claims
10
term “transducer head” is meant to include a recording
head and a playback head and a combined record and
ABSTRACT OF THE DISCLOSURE
Magnetic tape recording and reproducing apparatus
and method for use in connection with multi-track tape
at least one track of which is an intelligence track re
corded at one e?ective recording speed, and at least one
other track of which is an indexing signal recorded at a
higher playback speed, whereby during the high-speed re
wind operation, the indexing signal may be utilized to
aiford an instantaneous indication of the position of the
head relative to the tape. The invention is characterized
By the term “magnetic tape apparatus" used in this
speci?cation is meant apparatus for recording on mag
netic tape, or playing back magnetic tape, or both; the
15
playback head.
Other features and advantages of the invention will ap
pear from the following description of an embodiment
thereof, given by way of example in conjunction with the
accompanying drawings; in which:
20
` FIGURE 1 is a fragmentary diagram of a portion of
recorded magnetic tape, showing a suitable form of track
disposition for use in accordance with the invention;
' FIGURE 2 is a plan view, with the cover removed, of
by the provision of cam-operated indexing means for 25 a head assembly in accordance with the invention;
FIGURE 3 is a fragmentary sectional view taken on
shifting a magnetic playback head transversely of the
the line 3-3 of FIGURE 2, and
.
tape between positions assocíated with the various tracks,
Iespectively.
This invention relates to indexing magnetic tape rec
ords. Though not limited in its application to such appa
ratus, the invention is particularly suited for use in con
nection with so-called talking books, for use by the blind.
Talking books using magnetic tape have the advantage
FIGURE 4 is a further sectional view taken on the
line 4-4 of FIGURE 2.
The head assembly shown in the drawings is intended
30
for use with a magnetic tape recording of the kind which
is currently used with talking -books, consisting of a mag
netic tape having a width of 0.500". The number of
tracks used on such a tape is not standardized, but in one
arrangement 15 tracks are recorded, having a width of
approximately 0.015", with a guard space between ad
jacent tracks of 0.015". FIGURE 1 shows a fragment
of such a tape; the tape 10 has a spoken recital, for in
This is especially a problem with recorded text books,
stance of a book recorded on it in parallel tracks 11, 12,
where the user may require to select a particular passage
13, etc., it will be appreciated that such tracks will not
40
of the complete recording, for reference purposes. The
be visible on the tape itself. The recording speed may be
present invention is concerned with indexing by which a
uniform along the length of the tape, or as with the pres
user may rapidly ?nd a part of a recording.
cnt practice, the tape may be driven at a varying speed
The invention provides a magnetic tape record on
along its length, averaging one or two inches per second.
which a ?rst signal is recorded in a plurality of parallel
For convenience of the user, the talking 'book machine
spaced tracks, said ?rst signal being intelligible on play
has a fast wind device, when the speed is advanced at
of a long playing time but this makes it more dif?cult
for the user to ?nd a particular part of the recording.
ing back said tracks in succession with said tape being
fed at a tape playback speed and on which an indexing
signal is recorded in an indexing track disposed between
adjacent tracks of said plurality, said indexing signal
being audibly intelligible on playing back said indexing
track with the tape being fed at a tape spooling speed
substantially higher than said tape playback speed.
about ten times its playing speed.
In accordance with the invention, an index track is
recorded in the guard space between adjacent recital
50 tracks such as 11 or 12, such index tracks being indi
cated diagrammatically at 14, 15, 16, etc. in FIGURE 1.
The index tracks are less than the width of the guard
spaces and a convenient width is 0.005". Further, the
Another aspect of the invention provides a method of
index track will be a recording of suitable index infor
producing a magnetic tape record in which a signal is
55 mation, such as a spoken announcement of numbers cor
recorded at one effective recording speed in a plurality of
responding to page numbers, paragraph numbers, or the
spaced parallel tracks on the tape, and an indexing signal
like, and this information is recorded at a much higher
is recorded on the tape at a substantially higher effective
eñective recording speed, corresponding to the fast spool
recording speed in at least one indexing track spaced
from the tracks of said plurality.
Yet another aspect of the invention provides in a mag
netic tape apparatus for use in conjunction with a mag
netic tape record on which a ?rst signal for playback at
ing speed of the reproducing machine. When the user
60 wishes to ?nd a particular passage in the recording, for
example as indicated by an index in Braille, the playback
head is moved to scan the index track such as 14, 15,
16, etc. and the machine set to the fast feeding speed.
a playback tape speed is recorded in a plurality ot' paral
As the tape is thus advanced at high speed an intelligible
lel spaced tracks and an indexing signal for playback 65 reproduction will be atforded the user, indicating the posi
at a tape spooling speed is recorded in at least one index
tion of the main recording. The same playback head of
ing track disposed between adjacent tracks of said plu
the machine can be used to scan both the index tracks
rality; said machine comprising a transducer head, means
and the recital tracks alternatively.
for guiding the tape in a transducing path beside said
FIGURES 2, 3 and 4 are views of part of a talking
head, drive means for driving the tape along said path 70 book machine, by which the present invention can be car
substantially at said playback speed, and spooling drive
ried into eñect. -It will be understood that the remaining
means for driving the tape substantially along said path
parts of the machine, including the tape driving mecha
3
3,504,133
nism and the electronic and reproducing means can be
of conventional Construction.
The apparatus shown comprises a base plate 20, formed
of sheet metal, which ?ts on top of the tape deck of the
4
i
.
mitting the head 27 to come to its uppermost position.
The spring 57 enables lever 54 and plate 41 to move
relatively, and to yield if any excessive pressure should
be produced during this operation.
The rod 50 will be in the innermost position when the
cassette is in Operating position on the machine, and so
that the detent mechanism can be restored to operation,
Imeans are provided to disconnect rod 50` from lever 54.
For this purpose guide plate 5-1 is also formed with a
cam surface 62, against which the top end of cross pin
53 is held by the tension of spring 52. As the rod ap
rangement being such that when the cassette is in position
proaches the innermost limit of its travel the upper end
the spools are driven on spindles passing through open
of the cross pin will engage the cam surface 62, causing
ings 24, 25, in the base plate and platform.
the rod 50 to rotate about its longitudinal axis, and there~
Tape passing from one to the other of the spools is
gnided by means of upper and lower guide ?ngers 26, 15 by releasing the lower part of cross pin 53 from engage
ment with lever 54. Thereupon the lever moves under the
past a magnetic reproducing head 27. The head 27 can
tension of spring 55 to the position shown in FIGURE 2.
be moved vertically so that the narrow gap in the head
Means are provided for changing the vertical position
can be brought to register with the tracks recorded on
of head 27 step by step, to reproduce from the successive
the tape. A vertically movable head carriage is provided
by means of two posts 29 and 30, fastened to sub 20 recorded tracks on the tape. For this purpose there is
provided a lever 70, pivoted at 71 to the sub-assembly
assembly plate 31, upon which is mounted the carriage
plate 31, and carrying 'at its tip a spring-loaded pawl
32 consisting of a metal strip bent to U-shape. The arms
72 which is arranged to project into the path of star wheel
of the U are pierced and passed over the posts 29 and
40, and to advance it one tooth position each time lever
30, and the head is attached to the base of the U by means
of screws 33. A hair-pin spring 34a biases the carriage 25 70 is moved. The lever 70 moves between a ?xed abut
ment 73 and an adjustable abutment 74 and is spring
upwardly but the vertical position of the carriage is deter
biased by a flat leaf spring 75. The end of lever 70 ?may
mined by means of a cam groove member 34. Cam mem
be actuated by a solenoid controlled by a control signal
ber 34 has in it a cam groove 35, which is helical, and
recorded at the end of each track of the tape.
the carriage has a projectíng cam follower 36, the tip of
which enters the cam groove 35. The member 34 can 30
As thus far described, the apparatus can be used to
reproduce from a con'ventionally recorded tape, and to
rotate upon a spindle 37 fastened in the sub-assembly
allow the head 27 to be moved to a monitoring position
plate 31 and as the cam member 34 is rotated, the car
talking book apparatus; the base carries spring clips 21,
22, to enable it to be detachahly fastened to the appa
ratus. A platform 23 is secured above and parallel to
the base plate. The base plate normally carries a cover,
not shown, to form a receptacle for a magnetic tape
cassette, including two spools, also not shown, the ar 10
riage 32, and with it head 27, Will be moved vertically
to a predetermined position depending upon the angular
position of member 34.
An indexing mechanism is provided for member 34.
As shown, this comprises a star wheel 40, rigidly ?xed
to the member 34, and a detent roller plate 41, pivoted
on a short pillar at 42, fastened to sub-assembly plate
31. Plate 41 carries a detent roller 43, which is located 40
so as to drop into one of the detents of the star wheel 40.
The plate 41 is spring-biased in the clockwise direction,
so that roller 43 is biased into a detent of st-ar wheel
to reproduce from the index track, such as 14, 15, etc.,
it is arranged that the head has a further degree of
Vertical movement. This is very simply provided merely
by arranging that the cam follower 36 ?ts within the
groove of the cam member 34 with a small tolerance
of approximately 0.015". Normally the hairpin spring
34:: biases the carn follower 36 so that it bears against
the upper edge of the groove in the cam member, but if
the head carríage 32 is depressed, the carriage can be
moved downwardly against the tension of the spring, until
the cam follower ?bears against the lower edge of the cam
groove. It is arranged that in this position the head
40. The star wheel has sixteer? teeth, corresponding to
?fteen vertical positions of head 27 and a sixteenth posi 45 will read from the index track. Thus, the user can set the
tion which is a homing position for the head. In this
`controls of the apparatus to fast wind and by depressing
last position the cam follower 36 is arranged to enter a
the carriage 32 by a suitable control member, not shown,
longitudinal slot 3417 in the surface of the cam member
the index track will be read_ It may be that the head will
scan partiof the normal track when reproducing the index
34, joining the ends of the one turn helical cam groove,
track, but owing to the very great diiference in recording
so that under the action of the return spring 34a the car
speeds intelligibilíty is not a?ected. If through slight
riage will tend to move to the uppermost positionwhen
displacement of the head the index track is scanned dur
the cam follower encounters the longitudinal groove.
ing normal use, the index signal will be reproduced at so
The head is arranged to move to its uppermost posi
low a. frequency as not to be e?iciently ampli?ed by a
tion in this way when a cassette is inserted in the ma
chine. When this is done, the cassette is arranged to move 55 suitable reproducing ampli?er, so that interference is
minimised.
in actuating rod 50, mounted in the arms of a guide plate
While the embodiment of the invention described is of
51, the rod being biased to one limit of its movement
a complete apparatus, the sub-assembly can also be used
by a spring 52, its movement being limited by a cross
to modify an existing talking book apparatus.
pin 53. A lever 54, the end of which is pivoted on the
One convenient method of producíng large numbers
pillar at 42, extends into the path of the cross pin 53. 60
A tension spring 55 extends between the guide plate 51
of the tape records begins by the direct recording in a
and an attachment point 56 on lever '54 and a further
single track on standard master tape of the recital. This
recording is then transferred to a master cassette, where
and stronger spring 57 extends from the point 66 to a
projection on roller 43. When the rod 50 is moved end
the recital is sectionalízed into the appropriate number
wise on insertion of a cassettee, the cross pin 53 engages 65 of tracks (in the present instance, ?fteen). The master
cassette may then be used to .generate copy cassettes, and
the end of lever 54 and causes it to pivot in an anticlock
for this purpose the master and copy cassettes can be
wise direction, as seen in FIGUR-E 2, thereby releasing
placed in a high speed copying machine which feeds
roller 43 from engagement with the star wheel. By this
the cassette tapes at similar high speeds past playback
same movement a tail 58, forming part of plate 41, and
carrying on its underside a small projection 59, is moved 70 and record heads respectively. A signal picked up from
into engagement with a cardioid cam 60 attached to the
the master cassette is re-recorded on the copy cassette.
underside of star wheel 40. Thereby, the star wheel, now
freed of detent 43, is moved by the projection 519 to the
position in which the vertical groove in the cam face
so that all tracks are recorded simultaneously.
permits the çam fçllower to move vertieally, thus per
Separate heads are provided for each track of the cassettes,
The indexing signal may be inserted in several ways.
For instance, the appropriate passages of the recital may
5
3,504,133
be collated with the corresponding physical part of the
original master recording (identi?ed for instance by the
number of spool revolutions from the end of the tape),
and the tape run through again at a suitable high speed
while announcements are recorded as a second track of
the master tape, at the appropriate part of the tape. The UI
indexing announcements may for instance refer to the
page numbers or chapters and paragraphs, of a book if
this is what is recorded by the recital, and will slightly
precede the actual position of the corresponding passage 10
of the recital so that when the copy tape is played back
by the user he Will arrest the spooling of the tape at the
right passage. The indexing announcements may be re
corded both forwards and backwards so as to provide in~
telligible indexing whether the user is spooling the copy 15
6
?rst selection means for positioning said transducer
head means at a ?rst position on said guide means
to reproduce information recorded on said ?rst
track during the transport of the tape at said play
back speed, said ?rst selection means comprising
rotary cam means including a cylinder rotatable
about an axis parallel with said guide post means
and having on its outer periphery a helical cam
groove, and a cam follower member connected with
said transducer head means and extending into said
,cam groove;
second selection means for positioning said transducer
head means at a second position on said guide means
to reproduce the indexing information during the
transport of the tape at said rewind speed;
cassette forwards or backwards. With this method the in
dexing track may be transferred to the master cassette
and spring means biasing said transducer head means
on said guide post means in the direction from said
simultaneously with the main recital by use of separate
second position toward said ?rst position.
2. Apparatus as de?ned in claim 1, and further wherein
heads. The indexing signals could be recorded directly
onto the master cassette. In either of these methods, 20 the width of said helical groove is greater than the cor
separate heads are preferably provided in the high speed
copying machine to transfer the indexing track from the
respopding dimension of said follower member to` per
mit shifting of said transducer means on said guide post
master cassette to the copy cassettes simultaneously with
means from the ?rst position to the second position while
the main recital.
the cam means _is maintained stationary.
Another method of providing indexing signals, of 25
3. Apparatus as de?ned in claim 1 wherein said tape
a different type, is suitable where the user wishes to mark
includes a plurality of parallel pairs of said ?rst and sec
certain passages of the recital for future reference, Pro
ond tracks, and further including indexing means for
vision may be made in the user's playback apparatus for
rotatably stepping the cylinder between angular positions
recording a suitable tone in the indexing track of the
in which said transducer head is opposite successive ones
tape while the user is playing the recording at normal 30 of said ?rstvtracks, respectively.
playback speed. This tone will then appear at a con
4. Apparatus as de?ned in claim 3, wherein said in
siderably higher frequency when the tape is spooling at
high speed, if the index track is selected by depressing
the head of the playback machine described above.
In the playback machine, the playback head may be
dexing means includes a star wheel (40) connected with
said cylinder, detent means (43) cooperating with said
star wheel to step said cylinder between the indexing posi
tions, means (50, 54) for releasing said detent means
used to record the indexing tone. One suitable means
from said star wheel, and means including a longitudinal
for accomplishing this is to provide a record button for
slot (3412) in said cylinder for returning said transducer
switching an alternating signal, for instance at mains
head means to an initial position upon release of said
frequency, onto the windings of the playback head. No
detent means from said star wheel.
bias signal is necessary, and no record ampli?er need 40
References Cited
be provided. A safety device could be used so that the
indexing tone could not `be recorded into the main recital
UNITED STATES PATENTS
`
track.
2,468,198
4/1949 Heller ___________ _._ 179--100„2
I claim:
1. In a magnetic tape reproducing apparatus adapted 45 2,422,143 6/ 1947 Somers et al. ____ __ 179-1002
and including drive means for transporting the tape along
a given path alternately at a lower playback speed and
2„857,164
3,048,083
3,056502
10/ 1958
8/ 1962
10/ 1962
.Camras _________ __ 179-1002
Rosenbaum _____ __ 179-1002
Proctor _________ _._ 179-100.2
at a higher rewind speed, respectively, at least a ?rst track
3,166,328
1/1965
Roberts _________ _._ 179-100.2
for use in connection with a multi-track tape record
on said tape comprising an intelligence signal recorded 50
FOREIGN PATENTS
comprising an indexing track parallel With and spaced
810,111 5/1955 Great Britain.
from said first track, said indexing track being recorded
BERNARD KONICK, Primary Examiner
at the higher rewind speed, the invention which comprises
stationary guide post means arranged to extend trans 55 JEROME P. MULLINS, Assistant Examiner
versely of the tape;
transducer head means mounted for reciprocatory
U.S. Cl. X.R.
sliding movement on said guide post means;
274-4
at the tape playback speed and at least a second track
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