Note: Descriptions are shown in the official language in which they were submitted.
~ 1~38566
RCA 72,596
VIDEO DISC PLAYER
This invention generally relates to record players,
and more particularly, it relates to players suitable for
use with a record caddy.
In certain video disc systems, information is
stored on a disc record in the form of geometric variations
in the bottom of a continuous spiral groove disposed on the
record surface. The variations in capacitance between an
electrode incorporated in a groove-riding stylus and a
conductive coating disposed on the record surface are
sensed to reproduce the stored information. A capacitance-
type video disc system is illustratively disclosed in U. S.
Patent No. 3,842,194 (Clemens).
In such systems, it is advantageous to mount a
groove-riding pickup stylus in a demountable cartridge. The
cartridge is, in turn, mounted in a translatable carriage,
which is radially driven during playback in correlation
with the motion of the groove-riding stylus. U. S. Patent
No. 3,870,320 (Torrington), discloses a type of carriage
translating system.
It is beneficial to enclose a record in a thin
plastic caddy. For record loading, an occupied caddy is
inserted into an input slot provided in the player. A
record extracting mechanism disposed in the player removes
the record from the caddy during subsequent caddy withdrawal,
whereby the record is retained in the player. mhe player
is equipped with a platform for supporting the retained
record when it is disposed in an elevated position. The
retained record is transferred to the turntable for playback
during motion of the platform to a depressed position. For
subsequent record retrieval, the platform, with the retained
record resting thereon, is raised, and an empty caddy is
inserted into the player, thereby returning the record back
36 into the caddy. Withdrawal of the caddy, effects record
removal from the player. U. S. Patent No. 4,098,511
(~eedom) ~! Canadian Patent 1,104,717 (Coleman) and
Canadian Patent 1,107,859 (Torrington) illustrate systems
suitable for use with a record caddy.
B
1138566
1 -2- RCA 72,596
In such systems, the carriage is typically mounted
for side-to-side motion and the direction of caddy insertion
6 is from front-to-back, a direction which is orthogonal to
the carriage path. Such configuration imposes several
constraints on player design and construction: for example,
it is necessary that the starting position of the carriage
is beyond the record periphery: one of the caddy guiding
rails is mounted on the carriage to prevent interference
thereof with the motion of the carriage toward the record
center; a separate mechanism is needed to return the
carriage to the starting position subsequent to playback;
and a stylus landing adjustment mechanism is necessary to
16 insure that the stylus is lowered precisely over the
beginning of the recorded band during travel of the carriage
from an off-record starting position toward a postion
overlying the record.
The player incorporating the principles of the
preqent invention, overcomes hereinbefore mentioned
constraints. The player includes a housing provided with an
input 810t into which a record caddy is inserted along a
path for loading a record therein. A turntable centers and
rotatably supports a loaded record The player is equipped
26 with a mechanism for translating a pickup carriage along a
second path extending æubstantially parallel to the caddy
path at a speed correlated to the speed of rotation of the
turntable durin~ playback.
Pursuant to a further feature of the invention,
the direction of translation of the carriage during playback
is opposite to the direction of the caddy insertion. The
location of the caddy path relative to the carriage path is
such that the caddy engages the carriage, when the carriage
i at a position other than at a starting position, during
8~ a caddy insertion to reset the carriage at the starting
position .
I~l THE DRAWINGS:
.
FIGURE 1 is a plan view of a video record ~layer
incorporating the principles of the present invention:
FIGURE 2 is a perspective end view of the player
113~3S~6
1 -3- RCA 72,596
of FIGURE 1, with a depressible platform being shown in the
raised position;
FI~URE 3 is a perspective end view of the player
of EI5URES 1 and 2, with the depressible platform being
shown in the lowered position;
FIGURES 4 and 5 depict a record caddy, comprising
a jacket and a record retaining member, suitable for use
with the player of FIGURES 1-3;
FIGURE 6 illustrates a record extracting mechanism
disposed in the player of FIGURES 1-3;
FIGURES 7 and 8 show the operation of the record
extracting mechanism of FIGURE 6;
FIGURES 9 and 10 demonstrate the sequence involved
in transferring a record, resting on the depressible
platform of FIGURES 1-3, to the player turntable;
FIGURES 11-13 illustrate a mechanical toggle switch
suitable for use with a pickup carriage translating
mechanism provided in the player of FIGURES 1-3;
FI~URE 14 shows an arrangement suitable for
operating the toggle switch of FIGURES 11-13 by means of
contxols provided at the input end of the player;
FIGURE 15 depicts an alternate carriage translating
mechanism suitable for use with the player of FIGURES 1-3;
and
FIGURE 16 illustrates a stylus lifting/lowering
apparatus suitable for use with the player of FIGURES 1-3.
In FIGURES 1, 2 and 3, a video disc player 20
includes a housing 22 which is provided with an input slot
24 at the front end thereof, through which a record caddy is
inserted for loading an enclosed record into the player. A
turntable 26 includes a record centering spindle 28, and a
soft annular pad 30 for supporting the record. The
turntable diameter is made less than the record diameter,
36 and the soft annular pad supports the record in the grooved
area.
The turntable 26 is driven by a motor 32 (FIGURE
1) to rotate at a predetermined speed within preset limits
(e.g., 450 rpm + 0.01%). U. S. Patent No. 3,912,283
(~ammond, et al.), discloses an alternate form of a
1131~S66
1 -4- RCA 72,5~6
turntable drive system.
A platform 34, mounted on a shaft 36 which is
located at the non-input end of the housing 22, is subject
6 to motion between an elevated position (FIGURE 2) and a
depressed position (FI~URE 3). A pair of rails 38 and 40
are disposed on the platform 34. The rails have grooves 42
and 44 for guiding insertion of a caddy into the housing
along a path. The front ends of the caddy guiding grooves
are aligned with the input slot 24 when the platform is
occupying the elevated position for permitting insertion of
a caddy into the player.
As shown in FIGURES 4 and 5, the record caddy 50
comprises an outer jacket 52 and a record retaining member
16 54 removably located within the jacket. The retaining
member comprises (1) an annular portion 56, that encircles
the enclosed record 58, and (2) a spine portion 60, which
serves as a closure to keep dust and debris from entering
the record enclosing cavity. The spine has an opening 62
into which the latch arms 70 and 72 of a record extracting
mechanism 7~ (FIGURE 1) protrude during arrival of a
record caddy at a fully inserted position in the player to
effect record removal during subsequent caddy withdrawal.
The record extracting mechanism 7~ is mounted on
26 the platform 34, In the manner shown in FIGURE 6, the
extracting mechanism 74 includes latch arms 70 and 72
pivotally secured to a platform-mounted bracket 76. The
latch arms are alternated between an open condition
(FIGURES 6 and 7) and a closed condition IFIGURE ~), in
respon~e to each caddy arrival at the fully inserted
position in the player. The arrangement for rendering the
extxacting mechanism caddy responsive includes a pivotally-
mounted actuating arm 78 disposed in the caddy path. The
actuating arm advances a ratchet B0, carrying a square-
86 shaped cam ~, through 45 degrees each tim a cover arrivesat a fully inserted position in the player. Each
advancement of the square-shaped cam changes the condition
of latch arms from the condition they occupied ~rior to
cover insertion to the other condition thereof. Springs
(not shown) are provided for returning the actuating arm to
1138566
1 -5- RCA 72,596
the rest position thereof, and to bias the latch arms into
engagement with the square-shaped cam 82. A pawl (not
shown) is provided to prevent the ratchet from rotating in
6 the reverse direction when the actuating arm is returned to
its rest position. U. S. Patent No. 4,109,919 tElliott~
et al.), discloses a suitable caddy-actuated record
extracting mechanism.
To load a record into the player, the latch arms
70 and 72 are disposed in the closed condition (FIGURE 8),
the platform 34 is disposed in the elevated position
(FIGURE 2) and an occupied caddy is inserted through the
input slot 24 along the caddy guiding grooves 42 and 44.
The latch arms enter the opening 62 in the spine 60 as the
caddy reaches the fully inserted position in the player.
The engagement of the caddy with the actuating arm 78
indexe~ the latch arms into the cpread apart condition
(FIGURE 7), whereby the retaining member and the associated
record are locked to the platform. Subsequent withdrawal of
the caddy removes the record therefrom, thereby retaining
the record in the player resting on the raised platform
(FIGURE 9). To transfer the retained record to the
turntable, the platform is lowered to the depressed position
(FIGURE 10).
2~ For record retrieval, the above sequence is
reversed. The platform, wlth the record resting thereon, is
raised (FIGURE 9). The inner diameter of an opening 90 in
the platform 34 is sufficiently less than the record
diameter to positively insure lifting of the retained record
during upward motion of the platform. The platform is
provided with a set of depressible lifting pads 92, 93, 94,
95 and 96 (FIGUR~ 1) to align the record resting thereon
with the caddy guiding grooves 42 and 44 to cause return of
the record into an empty caddy during insertion thereof into
36 the player. As a caddy is loaded into the player, the
leading edge thereof depressed the lifting pads to allow
forward motion of the caddy. The engagement of the caddy
with the actuating arm 78 reindexes the latch arms to the
closed condition (FIGURE 8), thereby freeing the record from
the player. Subsequent caddy withdrawai removes the
113~566
-6- RCA 72,596
enc lo~;e(l record th erewi th .
The rails 38 and 40 are further provided with a
second set of grooves 100 and 102 (FIGURES 2 and 3) for
6 guiding a carriage 104 along a second path substantially
parallel to the caddy path (front-and-back). The carriage
is provided with a pair of projections (not shown), which
are respectively received in the carriage guiding grooves.
A pickup cartridge 106, carrying a groove-riding
stylus 107 at the end of a stylus arm 108, is installed in
a compartment provided in the carriage 104 (FIGURE 1). The
carriage is translated during playback along the rails
toward the turntable center (a direction opposite to the
direction of caddy insertion) in correlation with the speed
16 Of rotation of the turntable in the manner hereinafter
described. An armstretcher apparatus 109 oscillates the
pickup stylus back-and-forth along the groove so as to
offset cyclical errors in stylus/record relative velocity.
U. S. Patent No. 4,030,12~ (Allen), discloses a pickup
~0 cartridge suitable for use with the player described herein.
A suitable armstretcher apparatus is shown in U. S. Patent
No. 3,983,318 (Miller, et al.).
A pair of racks 110 and 112 are respectively
secured to the platform rails 38 and 40. A shaft 114,
26 carrying a set of pinions 116 and 118, is rotatably secured
to the carriage 104 (FIGURE 1). A respective one of the
pinions engages a respective one of the racks to ensure
that the carriage path lies radially of a turntable-
supported record throughout the operating range thereof.
Prior to playback, the carriage i9 restored to a
starting position. The resetting of the carriage to the
starting position is done automatically when a caddy is
inserted, for example, to retrieve a record, resting on the
platform while it is disposed in the raised position, from
3~ the player. The location of the caddy path relative to the
carriage path is such that a caddy engages the carriage
during insertion thereof into the player. The player is
dimensioned such that the arrival of the carriage-engaging
caddy at the fully inserted position in the player coincides
with the arrival of the engaged carriage at the starting
113~566
1 -7- RCA 72,596
position.
For playback, the platform, with a retained
record resting thereon, is depressed to transfer the record
6 to the turntable. The carriage is translated during
playback along the rails in a direction opposite to the
direction of caddy insertion in correlation with the speed
of rotation of the turntable. In addition to normal
correlated translation of the carriage during playback, the
carriage is translatable in either direction at a speed
independent of the speed of rotation of the turntable
during active search.
The carriage drive mechanism includes an endless
play belt 130, an endless search belt 132 and a carriage-
16 mounted, mechanical toggle switch 134 (FIGURE 1). The toggleswitch selectively connects one of the two belts to the
carriage to effect carriage translation by a selected one of
the belts. The play belt is driven in correlation with the
turntable rotational speed, and in a direction cau~ing
carriage translation toward the record center. The search
belt is driven independent of the turntable rotational
speed, and in either direction. The belts are driven in the
manner described hereinafter. The play belt is disposed
about a pair of pulleys 136 and 138, and the search belt i9
2B disposed about an additional set of pulleys 140 and 142.
Pulleys 136 and 140 are loosely mounted on the platform
shaft 36 for motion independent thereof. The other pulleys
138 and 142, serving as idling members, are freely mounted
for rotation about a pin 144 secured to the platform 34, and
extending parallel to the platform shaft 36. The respective
locations of the pulleys are such that the belts lie along a
path parallel to the carriage path.
The mechanisms for driving the tw~ belts will now
be described. As shown in FIGURE 1, a turntable-driven
3~ pulley 150 and a thumbwheel-driven pulley 152 are also
loo~ely mounted on the platform qhaft 36 for motion
independent thereof. The play belt driving pulley 136 and
the ~earch belt driving pulley 140 are respectively
secured to the turntable-driven pulley 150 and the
thumbwheel-driven pulley 152 for rotation therewith.
1138S66
1 -8- RCA 72,596
The turntable-driven pulley 150 is coupled to a
pulley 154 which, in turn, is driven by the turntable drive
motor 32 via a drive chain 156. The selection of proper
6 gear ratios permits carriage translation in correlation
with the radial motion of the groove-riding stylus during
playback.
~ serrated thumbwheel 160 is rotatably mounted in
the housing 22, and has a portion, which is accessible to
the user of the player through a slot in the front
instrument panel 230 of the player. A pulley 162 is mounted
coaxially with the thumbwheel for rotation therewith. The
coaxially mounted pulley drives the thumbwheel-driven
pulley 152 by means of endless belts 164 and 166 via an
16 intermediate pulley 168. It will be seen that the speed of
the bidirectional search belt is continuously variable over
a range of speeds in either direction by utilizing the
manually-actuated thumbwheel. All of the endless belts and
the pulleys herein used are equipped with teeth to provide
nonslip coupling.
An apparatus 170 (FIGURES 1 and 16) for causing
motion of the pickup stylus between a lowered position,
permitting engagement between the stylus and a turntable-
supported record, and a raised position, precluding stylus/
26 record engagement, is mounted in the carriage 104. The
pickup stylus is lowered for engagement with a turntable-
supported record during playback and active search. The
pickup stylus is raised when the player is in a pause mode
and when the carriage reaches an end-of-play position.
Essentially, as shown in FIGURE 16, the stylus
lifting/lowering apparatus 170 includes a stylus arm rest
172 moun~ed for motion between an elevated position and a
depressed position. The stylus arm rest in the elevated
position support4 the stylus arm 108 (FIGURE 1) in a manner
86 precludin~ stylus~record contact. The stylus arm rest in
the depre3sed position permits the stylus arm to occupy a
lowe~ed position. The lowered position of the stylus arm is
such that the stylus/record contact is established when the
carriage is in the over-record play position. An
electromagnet 174 is energized to repel a permanent magnet
113~566
1 -9- RCA 72,596
176 secured to the stylus arm rest to dispose the stylus arm
rest in the depressed position. A leaf spring 178 secured
to the stylus arm rest lifts the stylus 107 off the record
6 when the electromagnet is deenergized. A selectively
actuated plunger 179 depresses the stylus arm rest when
actuated. U. S. Patent No. 4,053,161 (Bleazey, et al.),
discloses such stylus lifting/lowering apparatus.
Disposed in the carriage are pickup circuits
coupled to the output of the groove-riding stylus for
developing a signal representative of the information
stored on the turntable-supported record. Signal processing
circuits, coupled to the output of the pickup circuits, are
located in the housing for developing a signal suitable for
16 application to a television receiver for audio/visual
presentation o~ the information stored on the record. U. S.
Patent No. 4,080,625 (Kawamoto, et al.), discloses suitable
pickup circuits. U. S. Patent No. 4,097,899 (Yu),
illustratively describes signal processing circuits.
To obtain various special effects, the mechanical
toggle switch 134 is thrown into an active search mode to
connect the carriage to the variable speed, bidirectional
search belt 132 to the exclusion of the constant speed,
unidirectional play belt 130. It will be noted that in the
2~ active search mode, as well as in the play mode, the stylus
lifing/lowering apparatus permits stylus/record engagement.
To realize, for example, fast forward motion, the carriage
is translated at a rapid rate in the forward direction by
rotating the thumbwheel 160 at appropriate speed in the
required direction, while the sytlus is allowed to ride on
the record, The reverse motion can be obtained by
translating the carriage in the reverse direction (i.e.,
away from the turntable center or toward the starting
position). To obtain stop motion effect, the carriage is
86 allowed to remain stationary, thereby causing the groove-
riding stylus to repetitively trace a selected set of groove
convolutions.
The mechanical toggle switch 134 for selectively
coupling the carriage to one of the two belts to effect
carriage translation by a chosen one of the belts will now
1~3B566
1 -10- RCA 72,596
be described. FIGURES 11, 12 and 13, respectively,
illustrate (1) the pause mode, wherein the carriage-mounted
toggle switch is disconnected from both belts, (2) the play
6 mode, wherein the toggle switch is secured to the play belt
130, and (3) the search mode, wherein the toggle switch is
connected to the search belt 132.
The toggle switch includes a block 180 secured to
the platform-mounted carriage for translation therewith.
The block has a pair of surfaces 182 and 184 defining a
slot 186 through which the upper runs of the play and the
search belts pass. The block is equipped with a recess 18
in communication with the top surface 182. ~ bifurcated
- plate 190 is mounted in the recess for arcuate motion about
16 a pin 192 to selectively occupy the above-mentioned three
positions. In the play mode, the upper run of the play
belt 130 is squeezed between the toggle plate and the
bottom surface 184 (FIGURE 12). In the search mode, the
upper run of the search belt 132 is held between the toggle
plate and the bottom surface 184 (FIGURE 13). In the
pause mode, the carriage is freed from both belts (FIGURE
11) .
The switch actuating mechanism includes a pin 194
rotatably secured to the carriage-mounted block. An
26 eccentric protrusion 196 is disposed at one end of the pin
194 for reception in a cutout 198 provided in the toggle
plate 190. The position and orientation of the pin l94
relative to the toggle plate is such that the rotation of
the pin effects pivotal motion of the toggle plate. A mode
select lever 200 is secured to the pin 194 to selectively
dispo~e the toggle plate in a selected one of the modes.
It is advantageous to be able to operate the
toggle switch by means of controls provided at the input end
of the player. One such arrangement 210 is illustrated in
a6 FIGURE 14. As shown therein, the mode selection lever 200
is curled upward at the free end thereof to provide an
offset tab 212. A flap 214 is swingably mounted on the
platform for arcuate motion about an axis lying parallel to
the carriage path. A torsional spring 216 is provided to
bias the mode selection lever to occupy an extreme position
~13~566
RCA 72,596
adjacent to the flap, whereby the carriage 104 is connected
to play belt 130. The flap is rotated to a first extent
(corresponding to the midway position of the toggle plate
6 190) and a second extent (corresponding to the other extreme
position of the toggle plate) in anti-clockwise direction
(when viewed from the input end) to, respectively, set the
toggle switch in the pause mode, wherein the carriage is
released from both belts, and the search mode, wherein the
carriage is under the influence of the search belt 132.
An extension 220 is disposed on the flap 214 at
the non-input end of the player for cooperation with struts
222 and 224. The struts 222 and 224 are actuated,
respectively, by a pause button 226 and a search button 228
16 (FIGURE 1) to cause the flap to, respectively, rotate to the
first and the second extent. Thus, operation of the pause
button and the search button indexes the toggle switch,
respectively, into the pause mode and the search mode. The
mode selection buttons are disposed on the front instrument
panel, and are of push-on/push-off variety.
The flat flap 214 is additionally equipped with a
~econd extension 232 at the input end of the player for
cooperation with a stationary overhanging member 234. The
relative location of the stationary memher is such that, when
26 the platform 34 is raised to the elevated position, the
stationary member depresses the second extension 232 to an
extent that disposes the toggle switch into the pause mode,
thereby freeing the carriage from both belts. Thus, the
action of the stationary member on the flap when the platform
i~ rai3ed allows restoration of the carriage to the starting
position, with freedom from interference by the carriage
translating mechanism, during insertion of an empty caddy
into the player for record retrieval.
The platform lifting/lowering mechanism will now
36 be described in conjunction with FIGURES 1-3. A function
selection lever 250, secured to a rotatably mounted wheel
252, extends through a slot provided in the front instrument
panel of the player. The function selection lever is moved
to the positions shown in FIGURES 2 and 3, respectively, to
raise and lower the platform. ~n the raised position of
1~3~566
1 -12- RCA 72,596
the platform, the front ends of the caddy guiding grooves 42
and 44 are aligned with the input slot to permit caddy
insertion and extraction. The depression of the platform,
with a retained record resting thereon, effects transfer of
the retained record to the turntable for playback. The
function selection lever may also serve to shut off power
to the player, for example, when it is shifted to a position
beyond the caddy in/out position (FIGURE 2).
The function selection wheel is provided with
peripheral, axial notches 254 and 256 corresponding to the
raised and lowered position of the platform. A detent 258,
secured to a pivotally mounted lever 260, is received in
one of the notches to releasably hold the function selection
lb wheel in a selected one of the positions thereof, A spring
262 urges engagement between the detent and the periphery
of the function selection wheel 252.
The linkage between the function selection lever
and the platform includes a pair of spaced levers 264 and
266 secured to a rotatably mounted shaft 268. A set of
platform-engaging rollers 270 and 272 are respectively
disposed at the free ends of the spaced levers. As shown
in FIGURE 1, an endless toothed belt 274 is disposed about
a toothed pulley 276, securely mounted on the shaft 268,
26 and another toothed pulley 278, mounted coaxially with the
function selection wheel for rotation therewith. The
relative angular location of the spaced levers 264 and 266
is such that the motion of the function selection lever
between the two positions causes corresponding motion of
the platform between the elevated and the depressed
position,
A rotatably-mounted dial 290 (~IGURE 1), bearing
an indicia indicative of the respective playing times
associated with ~istance traveled by the carriage from a
~6 starting position, is visible through a readout window
provided in the front instrument panel of the player. A
cord 292 extends between the carriage 104 and the indicia
bearing dial such that the displacement of the carriage
along the guiding rails effects synchronized rotation of
the dial. A torsion spring 294 is disposed about the axis
1138566
1 -13- RCA 72,596
of rotation of the dial such that it gets coiled during
translation of the carriage away from the starting position,
whereby energy is stored in the torsion spring. The coiled
6 spring applies a force to the carriage in a sense urying
carriage travel toward the starting position. The applied
force aids resetting of the carriage to the starting
position, when it is at a position other than the starting
position, during a caddy insertion. The cord 2g2 is passed
over a grooved pulley 296 and another grooved pulley 298.
The pulley 298 is coa~ially mounted on the platform shaft.
One end of the cord is fastened to the carriage-mounted
block 180, and a portion of the other end thereof is wrapped
around the stem portion of the dial. The stiffness of the
16 torsion spring is selected to give the desired feel to the
user of the player as he inserts a caddy into the player to
restore the carriage to the starting position.
An alternate carriage translating mechanism is
shown in ~IGURE 15. As shown therein, a spiral groove 310
is disposed on the periphery of a shaft 312 rotatably
secured to the carriage 314. A cord 316 has a portion
wrapped around the carriage shaft along the spiral groove
therein. The cord, moreover, has further portions
respectively passing over a grooved, turntable-driven pulley
26 318 and an idler pulley 320. A pair of pinions 322 and 324
are secured to the respective ends of the carriage shaft for
engagement with platform-mounted racks 326 and 328. A
drive chain 330 rotates the tur~able-driven pulley at a
speed such that the carriage is translated in synchronism
with a pickup stylus riding in an information bearing track
disposed on a turntable-supported record. For playing back
variable pitch records, the diameter of the peripheral
groove in the carriage shaft is varied in correspondence with
the variation in the record pitch, ~hereby providing precise
36 carriage translation throughout the operating range.
The input slot i5 covered with a flap for keeping
dust and debris from entering the record chamber in the
player. When the player is disposed in the caddy in/out
mode (FIGU~E 2) by means of the function selection lever,
the flap uncovers the input slot to allow caddy insertion
113~5~6
1 -14- RCA 72,596
and extraction. In other modes of the player, the flap
remains closed.
It will be noted that both the caddy guiding
grooves and the carriage guiding grooves are integrally
molded with the platform to provide a single-main-frame
construction. This permits a precise positioning of the
caddy relative to the carriage and the carriage relative
to the ~ntable throughout the operating range.
The mounting of the play belt driving pulley 136,
the search belt driving pulley 140, the turntable-driven
pulley 150, the thumbwheel-driven pulley 152 and the
grooved pulley 298 on the platform shaft 36 permits platform
motion without disturbing the rest of the player system.
16
2~
26
36
