Rotary recording medium reproducing apparatus having a jacket opening enlarging mechanism

A rotary recording medium reproducing apparatus reproduces a rotary recording medium on a turntable after an operation is performed in which the case accommodating the rotary recording medium therein is inserted into the reproducing apparatus and the case is then extracted from the reproducing apparatus with leaving the rotary recording medium with the apparatus. The reproducing apparatus comprises a jacket opening enlarging mechanism for engaging with the jacket to enlarge the opening according to the movement of the enlarging mechanism towards the innermost part of the reproducing apparatus from an inserting opening according to the insertion of the case, and a locking mechanism provided at a position substantially center along right and left directions of the enlarging mechanism, for normally locking the enlarging mechanism in the vicinity of the inserting opening to restrict the movement of the enlarging mechanism towards the innermost part of the reproducing apparatus. The locking mechanism is maintained in its original locking state upon insertion of the case or jacket in a state where a front edge of the case or jacket is slanted with respect to the enlarging mechanism, and assumes a locking released state only when the front edge is parallel with the enlarging mechanism and the locking mechanism is pushed by the front edge.

BACKGROUND OF THE INVENTION 
The present invention generally relates to rotary recording medium 
reproducing apparatuses capable of placing and leaving a rotary recording 
medium in a state possible for reproduction within the reproducing 
apparatus when a jacket having a lid for accommodating the recording 
medium therein is inserted into and then extracted from within the 
reproducing apparatus, and also capable of incasing the recording medium 
within the jacket so that the recording medium can be obtained outside the 
reproducing apparatus together with the jacket, when the empty jacket is 
inserted into and then extracted from within the reproducing apparatus. 
More particularly, the present invention relates to the above type of a 
rotary recording medium reproducing apparatus having a jacket opening 
enlarging mechanism for enlarging an opening of the jacket which is 
inserted into the reproducing apparatus upon loading and unloading of the 
recording medium with respect to the reproducing apparatus, wherein the 
jacket opening enlarging mechanism is provided with a locking mechanism 
which is maintained in a locked state even upon insertion of the case or 
the jacket if the insertion is not normal and is released of the locked 
state only when the case or the jacket is inserted in a normal position. 
Conventionally, in an apparatus for reproducing a rotary recording medium 
(referring to a video disc, PCM audio disc, and the like, and hereinafter 
simply referred to as a disc), there are types of apparatuses in which the 
disc is reproduced when the disc is loaded upon clamping and placing of 
the disc within the reproducing apparatus, by inserting into and then 
extracting a jacket (disc case) which has a lid and accommodates a disc 
therein, from within the reproducing apparatus. As a conventional 
apparatus of this type, a reproducing apparatus was proposed in a U.S. 
patent application Ser. No. 231,868 filed Feb. 5, 1981, entitled 
DISC-SHAPED RECORDING MEDIUM REPRODUCING APATUS, now U.S. Pat. No. 
4,352,174, in which the assignee is the same as that of the present 
application. This previously proposed reproducing apparatus operates 
together with a disc case comprising a jacket which has a space for 
accommodating a disc and an opening for allowing the disc to go in and out 
of the jacket, and a lid member inserted through the jacket opening for 
closing the jacket opening, where the reproducing apparatus comprises an 
inserting opening through which the case is inserted, a turntable for 
rotating the disc, holding means for holding at least one of the disc and 
the lid member provided at an innermost part on the opposite side from the 
inserting opening with respect to the turntable, a jacket opening 
enlarging mechanism provided in the vicinity of the inserting opening, 
capable of moving over the turntable between the position in the vicinity 
of the inserting opening and the innermost part of the reproducing 
apparatus, for enlarging the jacket opening by entering inside cutouts of 
the lid member upon insertion of the jacket into the reproducing apparatus 
through the inserting opening, lowering and raising means for lowering the 
disc to a position where the disc is placed on the turntable from a 
holding position where the disc is held by the holding means upon starting 
of the reproduction, and raising the disc to the holding position from the 
turntable upon finishing or discontinuing of the reproduction, a 
reproducing transducer for reproducing the disc placed onto the turntable, 
and moving means for moving the reproducing transducer from a waiting 
position to a reproducing position with respect to the disc. 
In the above previously proposed reproducing apparatus, a locking mechanism 
is provided for locking the jacket opening enlarging mechanism in the 
vicinity of the inserting opening. This locking mechanism is provided in 
order to prevent the enlarging mechanism from moving, when the reproducing 
apparatus receives a shock upon transport or the operator pushes the 
enlarging mechanism by his finger tips in mischief, for example. The 
locking mechanism is independently provided on both the right and left end 
sides of the enlarging mechanism. These locking mechanisms are 
simultaneously released by being pushed by the case, when the case is 
inserted through the inserting opening, to allow the enlarging mechanisms 
to move according to the insertion of the case. 
On the other hand, if the manner in which the case is inserted into the 
reproducing apparatus, it is normal for the case to be inserted straight 
in a position where the front surface edge thereof is parallel with the 
enlarging mechanisms. However, in some instances, the case may be inserted 
into the reproducing apparatus in a special manner, in which the rear edge 
of the case along the inserting direction which is held by the operator is 
repeatedly swung to the right and left. During such a special case 
inserting operation, the right and left locking mechanisms are released 
alternately, and one of the locking mechanisms constantly remain in the 
locking state. Hence, the enlarging mechanism is maintained in the locked 
state and usually does not move, although the locking provided by the 
locking mechanisms is incomplete. However, if the case is swung swiftly, 
for example, the following movement of the locking mechanisms towards the 
returning direction is delayed, and the right and left locking mechanisms 
both assume the lock releasing state. As a result, the locking with 
respect to the enlarging mechanism is released, and the enlarging 
mechanism is pushed by the case and is caused to move towards the 
innermost part of the reproducing apparatus. On the other hand, as will be 
described hereinafter, the positional relationship between the case and 
the enlarging mechanism in the above state becomes such that the front 
edge of the case is inclined with respect to the enlarging mechanism. That 
is, the enlarging mechanism may assume a state where one or both pairs of 
enlarging fingers of the enlarging mechanism do not engage with the 
opening of the inserted jacket, for example, that is, the enlarging 
mechanism may assume a state deviated from the normal state. Under such 
circumstances, even when the enlarging mechanism operates, the enlarged 
state of the jacket opening may become incomplete, or the jacket opening 
may not be enlarged at all. If the case or the jacket is inserted in a 
state where the enlarged state of its opening is incomplete, the loading 
of the disc into the reproducing apparatus and the recovery of the disc 
within the jacket cannot be carried out in a normal manner, and abnormal 
loading and recovery of the disc takes place. Moreover, an accident may 
occur in which the recording surface of the disc is scratched by the 
jacket when the disc enters and leaves the jacket. 
SUMMARY OF THE INVENTION 
Accordingly, it is a generally object of the present invention to provide a 
novel and useful rotary recording medium reproducing apparatus having a 
jacket opening enlarging mechanism, in which the above described problems 
have been eliminated. 
Another and more specific object of the present invention is to provide a 
rotary recording medium reproducing apparatus comprising a mechanism for 
locking jacket opening enlarging means at an original position in the 
vicinity of a case inserting opening, wherein the mechanism is provided 
substantially center along right and left direction of the enlarging 
means, so that the locking with respect to the enlarging means is only 
released when a case or jacket is inserted in a normal manner. According 
to the reproducing apparatus of the present invention, the case or jacket 
will not be inserted into the reproducing apparatus in a state where the 
opening of the case or jacket is closed or in an incompletely enlarged 
state. Therefore, abnormal loading and recovery of the disc is prevented, 
and further, accidents in which the disc is damaged are positively 
prevented. 
Other objects and further features of the present invention will be 
apparent from the following detailed description when read in conjunction 
with the accompanying drawings.

DETAILED DESCRIPTION 
In FIG. 1, a disc case 10 comprises a jacket 11 and a lid plate 12. The 
jacket 11 is assembled from a pair of jacket halves 13a and 13b, and 
comprises a flat cavity or space 14 therein. This space 14 is open at an 
opening 23 at the front of the jacket 11, and accommodates a disc 15. The 
lid plate 12 comprises a plate-shaped main lid body 16, and a rim portion 
17 formed unitarily at the front edge of the main lid body 16. A pair of 
engaging arms 18 are formed on both sides of the main lid body 16. The 
main lid body 16 of the lid plate 12 is inserted into a predetermined 
position within the jacket 11. Moreover, projections 19 of the engaging 
arms 18 engage into depressions 20, and thus, the lid plate 12 engages 
with the jacket 11. 
As shown in FIG. 2, a reproducing apparatus 30 substantially comprises a 
jacket opening enlarging mechanism 31 which constitutes an essential part 
of the reproducing apparatus according to the present invention, a 
turntable 32 for rotating the disc 15 placed thereon, a disc clamping 
mechanism 33 for clamping the disc 15, a lid plate locking mechanism 34 
for locking the lid plate 12, and the like. 
A reproducing transducer 42 comprises a pickup device 45 including a 
cantilever 44 provided with a reproducing stylus 43 at the tip end 
thereof, a resonator 46, and the like, and is mounted to a carriage 47. 
The carriage 47 is transferred in the directions of arrows Y1 and Y2 by 
means of a transferring mechanism 50, in a state where rollers provided on 
the carriage 47 roll along rails 49a and 49b which are respectively 
provided on a chassis 48. 
The disc clamping mechanism 33 is provided at the inner part of the 
reproducing apparatus 30 on the opposite side of an inserting opening 51, 
and comprises a pair of upper and lower clamping fingers 52. 
Upon reproduction of the disc 15, the disc case 10 is inserted through the 
inserting opening 51 of the reproducing apparatus 30, by inserting the 
disc case 10 with the side of the lid plate 12 into the direction of an 
arrow X1. 
When the disc case 10 is inserted into the reproducing apparatus 30 in the 
above described state, the jacket opening enlarging mechanism 31 is pushed 
in the direction of the arrow X1 by the disc case 10. As the jacket 
opening enlarging mechanism 31 moves, the front part of the upper and 
lower jacket halves 13a and 13b are enlarged upwards and downwards, to 
enlarge the opening 23 as will be described hereinafter. 
When the disc case 10 is inserted into the innermost part of the 
reproducing apparatus 30 together with the enlarging mechanism 31 over the 
turntable 32, cutouts 22 of the lid plate 12 becomes locked by the lid 
plate locking mechanism 34. Hence, the lid plate 12 is locked and held at 
the innermost part of the reproducing apparatus 30. 
In addition, engagement releasing members 54 enter inside the openings on 
the right and left sides of the disc case 10, and push sloping surfaces at 
the tip ends of the engaging arms 18. Accordingly, the engaging arms 18 
are respectively distorted inwards, and the projections 19 respectively 
slip out from the depressions 20, to release the engagement of the lid 
plate 12 with respect to the jacket 11. Further, the disc 15 is clamped at 
a predetermined height by the clamping fingers 52. 
Next, the jacket 11 is extracted in the direction of an arrow X2. Since the 
lid plate 12 and the disc 15 are respectively locked and clamped as 
described above, only the jacket 11 is moved in the direction of the arrow 
X2, leaving behind the lid plate 12 and the disc 15. Accompanied by this 
extraction of the jacket 11, the lid plate 12 and the disc 15 are 
relatively extracted from within the jacket 11. In a state where the 
jacket 11 is completely extracted from the reproducing apparatus 30, the 
disc 15 is supported horizontally at a position directly above the 
turntable 32. 
When a play operation is carried out thereafter, the disc 15 is lowered and 
placed onto the turntable 32, and is clamped by a disc clamping mechanism 
35. In addition, the disc 15 is rotated clockwise together with the 
turntable 32. 
Moreover, the carriage 47 moves in the direction of the arrow Y1 from a 
waiting position, to reproduce the information signal by the reproducing 
stylus 43 which relatively scans over the recording surface of the disc 
15. 
Next, description will be given with respect to an operation in which the 
disc 15 is recovered from within the reproducing apparatus 30. 
Upon completion of the reproducing operation, the disc 15 is pushed 
upwards. Further, the disc 15 thus pushed upwards, is clamped by the disc 
clamping mechanism 33. 
Upon recovery of the disc 15, an empty jacket 11 is again inserted into the 
reproducing apparatus 30 through the inserting opening 51, with the 
opening of the jacket 11 first. Hence, the enlarging mechanism 31 is 
pushed by the jacket 11 and moves in the direction of the arrow X1, to 
enlarge the opening of the jacket 11. As the jacket 11 is inserted along 
the direction of the arrow X1, the disc 15 is relatively inserted into the 
jacket 11 through the opening of the jacket 11. 
When the jacket 11 is inserted into the innermost position within the 
reproducing apparatus 30, the disc 15 becomes completely incased within 
the jacket 11, and further, the locked lid plate 12 is relatively inserted 
within the opening of the jacket 11. 
As the jacket 11 is inserted into a final position, the disc 15 becomes 
accommodated within the jacket 11, and the main part of the lid plate 12 
which has been locked, becomes inserted inside the jacket opening. 
Furthermore, the lid plate locking mechanism 34 releases the lid plate 12. 
Therefore, when the jacket 11 is extracted in the direction of the arrow 
X2, the lid plate 12 then moves in the direction of the arrow X2 together 
with the jacket 11, and the disc 15 is pushed by the lid plate 12 and 
becomes forcibly pushed out in the direction of the arrow X2 by the 
holding part thereof. Accordingly, the disc 15 separates from the 
reproducing apparatus 30 to become recovered within the disc case 10. 
Next, description will be given with respect to an embodiment of a jacket 
opening enlarging mechanism which constitutes an essential part of the 
reproducing apparatus according to the present invention, by referring to 
FIG. 3 and the following figures. In each of these figures, those parts 
which are the same as those corresponding parts in FIGS. 1 and 2 are 
designated by the same reference numerals, and their description will be 
omitted. 
The jacket opening enlarging mechanism 31 is substantially constructed from 
elongated upper and lower enlarging members 61 and 62 extending in the 
directions of the arrows Y1 and Y2, and sliders 65 and 66 respectively 
fitted on guide rails 63 and 64. The sliders 65 and 66 respectively 
support both ends of the above enlarging members 61 and 62. In accordance 
with the insertion and extraction of the disc case 10, the above jacket 
opening enlarging mechanism 31 moves in the directions of the arrows X1 
and X2 under the guidance provided by the guide rails 63 and 64, passing 
above the turntable 32 between a position in the vicinity of the inserting 
opening 51 and the innermost part of the reproducing apparatus 30. 
The upper enlarging member 51 is axially supported by bearing parts 65a and 
66a provided at the upper parts of the sliders 65 and 66, at trunnions 67a 
and 67b provided at the left and right sides of the upper enlarging member 
61. Accordingly, the upper enlarging member 61 is capable of pivotting 
towards the directions of arrows A1 and A2. On the other hand, the lower 
enlarging member 62 is also axially supported in a similar manner, to 
pivot in the directions of arrows B1 and B2. Trunnions 68a and 68b (only 
one shown) of the lower enlarging member 62 are respectively supported by 
bearings (not shown) provided on the lower parts of the sliders 65 and 66. 
The trunnions 67a, 67b, 68a, and 68b are respectively disposed on the 
enlarging members 61 and 62 at lateral edges, in the direction of the 
arrow X2. In addition, tension coil springs 69a and 69b are respectively 
stretched between the ends of the upper and lower enlarging members 61 and 
62, to urge these enlarging members towards closing directions indicated 
by the arrows A1 and B1. 
Furthermore, a downwardly bent part 61a is formed at the edge on the 
opposite side from the trunnions 67a and 67b, in the upper enlarging 
member 61. Two enlarging fingers 61b and 61c are provided on this 
downwardly bent part 61a at two positions. These enlarging fingers 61b and 
61c extend towards the inserting opening 51 (in the direction of the arrow 
X2), at positions confronting the two cutouts 22 of the lid plate 12 of 
the inserted disc case 10. Similarly, the lower enlarging member 62 is 
also provided with a bent part 62a and enlarging fingers 62b and 62c. The 
two sets of enlarging fingers 61b, 61c, 62b, and 62c confront in the 
upward and downward directions, and mutually cooperate to carry out a 
jacket opening enlarging operation as will be described hereinafter. In 
addition, locking pins 70 and 71 are respectively provided at a central 
position along the right and left directions, on the upper and lower 
enlarging members 61 and 62. These locking pins 70 and 71 respectively fit 
into corresponding windows 24 and 25 in the jacket halves 13a and 13b when 
the jacket 11 is enlarged, to mechanically link the jacket 11 and the 
enlarging mechanism 31. 
In addition, the upper and lower enlarging members 61 and 62 are 
respectively provided with rollers 72a and 72b, and rollers 73a and 73b, 
for rolling over the guide rails 63 and 64 to separate the enlarging 
members in the upward and downward directions. 
When the jacket opening enlarging mechanism 31 is positioned on the side of 
the inserting opening 51 as shown in FIG. 2, the rollers 72a and 73a (72b 
and 73b) oppose the narrow part of tapered parts 63a on the front of the 
guide rail 63 (64). At this point, the upper enlarging member 61 is 
angularly rotated in the direction of the arrow A1 due to a force exerted 
by the tension coil springs 69a, and is in a downwardly inclined state. 
The lower enlarging member 62 at this point is rotated in the direction of 
the arrow B1, and is in an upwardly inclined state. Therefore, the bent 
parts 61a and 62a at the free edges of the upper and lower enlarging 
members 61 and 62, are pressing against each other, thereby closing the 
inserting opening 51 as will be understood from FIGS. 2 and 3. Thus, the 
upper and lower enlarging members 61 and 62 have a function of closing the 
inserting opening 51. 
Moreover, in the above described state, the enlarging fingers 61b, 61c, 
62b, and 62c mutually close upon each other, and are at a height position 
at the center of the inserting opening 51. 
Lock levers 75 and 76 are respectively provided on the sliders 65 and 66. 
The lock lever 75 is substantially of an L-shape in the plan view, and is 
axially supported on the upper surface of the slider 65 by a pin 77, at a 
part in the vicinity of the bent portion of the lock lever 75. An E-shaped 
part 75a is formed on one arm portion of the lock lever 75. The E-shaped 
part 75a comprises upper and lower fingers 75b and 75c and a center finger 
75d. This lock lever 75 is urged to angularly rotate clockwise by a coil 
spring 79 which is stretched across between the tip end part of the other 
arm portion of the lock lever 75 and a bracket 78 which is fixedly screwed 
onto the slider 65. 
The lock lever 76 is of the same construction as the lock lever 75, and 
those parts of the lock lever 76 which are the same as those corresponding 
parts of the lock lever 75 have the same subscripts. The lock lever 76 is 
axially supported by a pin 80, and is urged to angularly rotate 
counterclockwise by a coil spring 82 which is stretched across between the 
tip end part of an arm portion of the lock lever 76 and a bracket 81 which 
is fixedly screwed onto the slider 66, similarly as in the case of the 
lock lever 75. 
When the jacket opening enlarging mechanism 31 is positioned on the side of 
the inserting opening 51 as shown in FIG. 2, the lock levers 75 and 76 are 
at angularly rotated positions shown in FIGS. 2, 3, and 4. That is, the 
E-shaped parts 75a and 76a are moved in the direction of the arrow X2, and 
the upper fingers 75b and 76b oppose the upper surface of the upper 
enlarging member 61 while the lower fingers 75c and 76c oppose the lower 
surface of the lower enlarging member 62, to restrict the angular rotation 
of the enlarging members 61 and 62 in the directions of the arrows A2 and 
B2 (enlarging directions). As a result, the movement of the enlarging 
mechanism 31 towards the direction of the arrow X1 is restricted. 
In addition, the center fingers 75d and 76d are inserted between the upper 
and lower enlarging members 61 and 62, and are at positions corresponding 
to the left and right ends of the front surface facing the inserting 
direction of the disc case 10 or jacket 11 which is inserted into the 
reproducing apparatus 30 through the inserting opening 51. 
A locking mechanism 90 for locking the jacket opening enlarging mechanism 
31, which constitutes an essential part of the apparatus according to the 
present invention, is provided at a position substantially center along 
the right and left directions on the upper enlarging member 61. This 
locking mechanism 90 substantially comprises a locking member 91 provided 
on the upper enlarging member 61, and a bracket 92 fixed to the main 
apparatus body, for engaging with the locking member 91. 
The locking member 91 comprises a case or jacket insertion detecting arm 
part 91a, and a locking arm part 91b, and is provided angularly rotatable 
by a pin 93 at the upper surface of the upper enlarging member 61 at a 
position substantially center along the right and left directions thereof. 
The locking member 91 is urged to angularly rotate clockwise by a torsion 
spring 94. The detecting arm part 91a is a downwardly bent part, which 
penetrates through a cutout 61d of the upper enlarging member 61, to 
protrude into a case inserting path of the enlarging mechanism 31 formed 
between the upper and lower enlarging members 61 and 62. The detecting arm 
part 91a is provided at a position substantially center of the enlarging 
mechanism 31, at an inner part along the case inserting direction. By this 
arrangement of the detecting arm part 91a, the detecting arm part 91a is 
pushed by a front edge 11a of the jacket 11 on the side of the opening 23, 
when the disc case 10 is inserted in a normal manner, and is not pushed by 
the front edge 11a if the disc case 10 is inserted in a slanting manner, 
as will be described hereinafter. The locking arm part 91b is an upwardly 
bent part, and penetrates through an inner part 95a of an L-shaped cutout 
95 in the bracket 92. 
In a state where the locking member 91 is angularly rotated clockwise, the 
enlarging mechanism 31 is restricted of its movement along the direction 
of the arrow X1 because the locking arm part 91b becomes locked by a hook 
part 96. The locking member 91 assumes a state movable along the direction 
of the arrow X1, when the locking arm part 91b moves out from the inner 
part 95a of the L-shaped cutout 95 on the side of a path 95b by the 
counterclockwise angular rotation of the locking member 91. 
Next, description will be given with respect to the operation of the 
enlarging mechanism 31 having the above described construction, especially 
regarding the operation of the locking mechanism 90. 
The disc case 10 is inserted into the reproducing apparatus 30 along the 
direction of the arrow X1, with a height position shown in FIG. 6A. When 
the disc case 10 is inserted in a normal position where the front edge 11a 
thereof is parallel with the enlarging mechanism 31, the disc case 10 
enters within the innermost part of the enlarging mechanism 31. The disc 
case 10 and the enlarging mechanism 31 accordingly assume a state shown in 
FIG. 6B. That is, the enlarging fingers 61b and 62b (61c and 62c) enter 
within the cutouts 22 of the lid plate 12 to relatively enter within the 
opening 23 of the jacket 11, and the windows 24 and 25 of the jacket 11 
respectively oppose the locking pins 70 and 71. 
Further, the right and left end parts of the jacket 11 push the center arm 
parts 76d and 75d of the locking levers 76 and 75, to angularly rotate the 
locking levers 75 and 76 counterclockwise and clockwise, respectively, as 
shown in FIG. 7. Due to the angular rotation of these locking levers 75 
and 76, the arm parts 75b and 76b at the upper parts thereof and the arm 
parts 75c and 76c at the lower parts thereof respectively separate from 
the positions opposing the parts in the vicinity of the right and left 
ends of the enlarging members 61 and 62. As a result, the enlarging 
members 61 and 62 assume states angularly rotatable in the enlarging 
directions (in the directions of the arrows A2 and B2), respectively 
against the forces exerted by the springs 69a and 69b, and the enlarging 
mechanism 31 is released of the locking at the right and left ends 
thereof. In addition, the center part of the front edge 11a of the jacket 
11 almost simultaneously pushes the detecting arm part 91a, to angularly 
rotate the locking member 91 counterclockwise, as indicated by a two-dot 
chain line in FIG. 4 and FIG. 7. Thus, the locking arm part 91b escapes 
from the inner part 95a unto the path 95b. Therefore, the locking 
mechanism 90 is put into a lock released state. 
Accordingly, the enlarging mechanism 31 is released of the locking by the 
right and left locking mechanisms and the central locking mechanism 90, 
simultaneously, and becomes movable along the direction of the arrow X1. 
When the disc case 10 (jacket 11) is further inserted, the enlarging 
mechanism 31 moves in the direction of the arrow X1 as shown in FIGS. 6C 
and 7. Hence, the rollers 72a and 73a ride over the tapered parts 63a to 
reach the upper and lower surfaces of the guide rail 63, and the enlarging 
members 61 and 62 respectively rotate angularly in the directions of the 
arrows A2 and B2. 
In the above state, the enlarging finger 61b (61c) positively locks and 
pulls up the jacket half 13a, and the enlarging finger 62b (62c) 
positively locks and pulls down the jacket half 13b. Moreover, as will be 
described hereinafter, the windows 24 and 25 are positively fitted with 
the locking pins 70 and 71, to normally enlarge the jacket opening 23 in 
the upward and downward directions. 
The disc case 10 is thereafter inserted along the direction of the arrow X1 
in the enlarged state, and only the jacket 11 is extracted in the 
direction of the arrow X2, to normally load the disc as previously 
described. 
When the jacket 11 assumes the enlarged state, the windows 24 and 25 of the 
jacket halves 13a and 13b respectively fit over the locking pins 70 and 71 
of the enlarging members 61 and 62. Accordingly, the jacket 11 and the 
enlarging mechanism 31 become engaged, and upon extraction of the disc 
case 10, the enlarging mechanism 31 is pulled back together with the 
jacket 11 along the direction of the arrow X2 in a state where the windows 
24 and 25 are fitted over the locking pins 70 and 71. 
One side surface 95b1 of the path 95b is formed as a sloping surface, so 
that when the enlarging mechanism 31 returns to its original position, the 
locking arm part 91b is guided by the above side surface 95b1 and 
positively enter within the L-shaped cutout 95. 
Next, description will be given with respect to the operation of the 
locking mechanism 90, when an attempt is made to insert the disc case 10 
while swiftly swinging the disc case to the right and left as described 
before. In the conventional apparatus, the disc case will be inserted in a 
state where the opening of the jacket is not enlarged under such an 
abnormal insertion. 
If the rear end of the disc case 10 is swung towards the right in a state 
where the tip end thereof is inserted within the enlarging mechanism 31, 
the disc case 10 assumes a state indicated by a one-dot chain line in FIG. 
4. On the other hand, if the disc case 10 is swung towards the left, the 
disc case 10 assumes a state indicated by a two-dot chain line in FIG. 4. 
That is, when the disc case 10 is swung rightwards, the right lock lever 76 
is pushed by the right end of the jacket 11 and assumes a locking released 
state. Conversely, if the disc case is swung leftwards, the left lock 
lever 77 is pushed by the left end of the jacket 11 and assumes a locking 
released state. If such a swinging operation is swiftly performed 
exceeding the speed with which the lock levers 76 and 77 are returned, the 
lock levers 76 and 77 both assume the locking released state for an 
instant. Hence, in the conventional apparatus, because both the lock 
levers 76 and 77 instantaneously assume the locking released state, the 
jacket 11 becomes inserted in a state where the front edge 11a thereof is 
slanted with respect to the longitudinal direction of the enlarging 
mechanism 31 as indicated by the one-dot chain line and the two-dot chain 
line in FIG. 4. That is, the jacket 11 becomes inserted in a state where 
the enlarging fingers 61b (61c) and 62b (62c) are only partially inserted 
or not at all inserted within the opening 23, or in a state where the 
windows 24 and 25 assume positions shifted from those of the corresponding 
locking pins 70 and 71. As a result, the jacket 11 may be inserted into 
the reproducing apparatus 30 in a state where the opening 23 is not at all 
enlarged or enlarged in an incomplete manner. 
However, according to the reproducing apparatus of the present invention, 
the detecting arm part 91a of the locking member 91 is provided at a 
center position along the right and left directions of the enlarging 
mechanism 31, at the inner part thereof. Hence, due to this arrangement of 
the detecting arm part 91a, the detecting arm part 91a is not pushed by 
the front edge 11a of the jacket 11 upon swinging of the disc case 10 or 
the jacket 11 in the rightward and leftward directions, even at the 
extreme points of the swinging. Thus, the locking member 91 remains in the 
original position angularly rotated clockwise, and is maintained in the 
locking state. Even if the disc case 10 or the jacket 11 is inserted in an 
abnormal manner as described above, the enlarging mechanism 31 is locked 
in the vicinity of the inserting opening 31 and cannot move. As a result, 
the disc case 10 or the jacket 11 is prevented from being inserted into 
the reproducing apparatus 30 in a state where the opening 23 is not at all 
enlarged or enlarged in an incomplete manner. This accordingly prevents 
accidents upon loading and recovering of the disc, and the disc is 
prevented from being damaged. 
The detecting arm part 91a of the locking member 91 is arranged and 
provided at a position away from the front edge 11a of the jacket 11 which 
is inserted in an abnormal manner in the plan view, as described above. In 
addition, the arrangement is such that when the upper enlarging member 61 
of the enlarging mechanism 31 rotates angularly in the direction of the 
arrow A2, the detecting arm part 91a moves upwards away from the upper 
jacket half 13a with respect to the height direction thereof. For this 
reason, even if the enlarging mechanism 31 is forcibly opened in its 
original position due to the abnormal insertion of the disc case 10 or 
jacket 11, and the disc case 10 or jacket 11 passes through the enlarging 
mechanism 31 to enter within the reproducing apparatus, the disc case 10 
will move below the detecting arm part 91a and the detecting arm part 91a 
will therefore not be pushed. Accordingly, the locking mechanism 90 is 
maintained in its original state, and the enlarging mechanism 31 remains 
locked in its original position by the locking mechanism 90. 
Furthermore, the detecting arm part 91a of the locking member 91 protrudes 
downwards from the upper enlarging member 61, and is provided at the inner 
part. Hence, it is convenient in that the external appearance is not 
spoiled, because the detecting arm part 91a is hidden from the outside. 
Moreover, there is less chance of this detecting arm part 91a from being 
played in mischief. When a person is wiping the front face of the 
reproducing apparatus 30, for example, there is almost no possibility of 
his finger tips being caught by the detecting arm part, and assures 
safety. 
The arrangement of the enlarging mechanism 31 is not limited to that 
described before, and the locking mechanism 90 may be provided at the 
center of the lower enlarging member 62 instead of the upper enlarging 
member 61, or provided on both the upper and lower enlarging members 61 
and 62. 
In addition, it should be apparent that the lock levers 75 and 76 provided 
on both sides of the enlarging mechanism 31 may be omitted in the 
reproducing apparatus according to the present invention. 
Further, the present invention is not limited to these embodiments, but 
various variations and modifications may be made without departing from 
the scope of the present invention.