JPH0127164Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a compact disc playback device.

Compact discs differ from conventional analog records in that they have an information recording surface formed by a plurality of minute pits (grooves), and the information is generally read out without contact using a laser beam. A protective film made of thin transparent resin is provided on the information recording surface, but if fat such as finger grime adheres or is scratched, the laser beam may be refracted or scattered, causing false detection. There is a high possibility that this will happen. For this reason, compact disks are stored in standardized general-purpose cassette cases, and care must be taken when handling them.

Under these circumstances, in order to be more careful when handling compact discs, it is now possible to automatically open the cassette case and remove the compact disc stored in the cassette case without touching it with your fingers. It would be desirable to develop an automatic loading mechanism that can be removed and placed into the playing position. However, it is not desirable to use a new special cassette case that is different from the current general-purpose cassette case that has already been agreed upon, as it may cause unnecessary confusion on both the manufacturer's side and the user's side.

This idea was devised in view of the above-mentioned circumstances, and its purpose is to allow the use of the current general-purpose cassette case as is, and to allow the lid to be removed from the compact disk when the cassette case is inserted into the main body of the device. To provide a compact disc playback device equipped with a cassette case opening/closing means that can automatically open to an angle that does not interfere with the playback of a compact disc.

Hereinafter, this invention will be described in detail with reference to embodiments shown in the accompanying drawings.

First, referring to FIG. 1, a general-purpose cassette case for compact discs will be briefly described. This cassette case 1 has a case board 2
and a lid 3 pivotally attached to the case base plate 2 so as to be openable and closable. An inner collection chuck 5 for removably holding a compact disk (hereinafter referred to simply as a disk) 4 is provided approximately at the center of the case substrate 2. This inner collet chuck 5 is made up of an assembly of inverted L-shaped elastic pieces 6 made by dividing a bottomed cylindrical boss member into a plurality of pieces in the center direction. The elastic piece 6 is deformed toward the center, the entire diameter is reduced, and the restraining force on the disk 4 is released. Furthermore, a surrounding wall 7 that fits into the inner surface of the side wall of the lid 3 and a flange 8 that abuts the open end of the lid 3 are formed on the periphery of the case substrate 2 . On the other hand, a pair of square holes 9, 9 in the front and rear are bored in both side walls of the lid body 3, respectively, and this invention makes it possible to automatically open the lid body 3 by using these square holes 9. Intended.

FIG. 2 shows a schematic perspective view of the reproduction device according to this invention. That is, this playback apparatus is equipped with a cassette case opening/closing means 11 for automatically opening and closing the cassette case 1. Further, this playback device takes out the disk 4 from inside the cassette case 1 opened by the opening/closing means 11, places it on the turntable 12, and returns the disk 4 back into the cassette case 1. A disk transport means 13 including an arm 14 is provided. Note that each of the cassette case opening/closing means 11, turntable 12, and disk transport means 13 is provided on a deck side base 15,
The cassette case 1 is inserted horizontally onto the base 15 from an insertion opening (not shown) into a cassette case mounting section.

Referring to FIGS. 3 to 5, the cassette case opening/closing means 11 has a vertical pin 16 on the side of the cassette case mounting portion of the base 15.
The cassette case 1 has a dog 17 that is rotatably supported by a shaft, and an arm 18 that acts on the lid 3 of the cassette case 1 in conjunction with the movement of the dog 17. The dog 17 has a tip 17a that comes into contact with the front surface of the cassette case 1 that is inserted, and in the normal state, the dog 17 is in the state shown in FIG. 3 by the stopper pin 19.
That is, it is kept in its initial state. Further, this dog 17 is integrally provided with an arm shifter 20. In this case, the arm shifter 20 is provided with the dog 1 that engages with the stopper pin 19 described above.
7 in the initial state, and the arm 18
a first cam surface 20b that holds the arm 18 in an inoperative state (non-engaged state) with respect to the lid body 3, and a second cam surface 20c that releases this inoperative state and engages the arm 18 with the lid body 3. is formed.

The arm 18 consists of a main arm 22 and an auxiliary arm 23 articulated to one end of the main arm 22. In this case, on one end side of the main arm 22,
A first stopper 24 (see FIG. 2) that prevents the auxiliary arm 23 from rotating counterclockwise from the solid line position in FIG. A stopper (not shown) is provided, and the auxiliary arm 23 is normally held by the coil spring 25 at the position shown in solid line in FIG. There is. A pin 26 is implanted at the tip of the auxiliary arm 23 to fit into a square hole 9 formed in the lid 3. Main arm 22
The other end is supported by a rod 28 held horizontally on the base 15 via a pair of bearing brackets 27, 27. A coil spring 29 is wound around the rod 28, which presses the main arm 22 toward the side surface of the cassette case 1 and urges the main arm 22 to rotate counterclockwise in FIG. The main arm 22 also includes a cam surface 20 of the arm shifter 20.
A protrusion 22a is formed to serve as a cam follower of cam surfaces 20b and 20c.
It is always in pressure contact with either 0c. In addition, in this embodiment, the cassette case opening/closing means 11
Although only one is shown, they are actually provided on both sides of the cassette case mounting section.

The operation of this cassette case opening/closing means 11 will be explained. Initially, the dog 17 is held in the state shown in FIG. 3 by the stopper pin 19, and the arm 18 is placed in an inoperative state against the coil spring 29 by the cam surface 20b of the arm shifter 20. When the cassette case 1 is inserted through the insertion slot (not shown), the front side of the cassette case 1 is inserted into the tip 17 of the dog 17.
a and rotate the dog 17 clockwise in FIG. 3. At that time, the tip 17a of the dog 17 is
engages with the upper surface of the peripheral flange 8 of the case substrate 2;
Thereafter, the case substrate 2 is held down to prevent its vertical movement. When the dog 17 is rotated by a predetermined angle (for example, 15 degrees) by the cassette case 1, the arm shifter 20 also rotates, and the protrusion 22a of the main arm 22, which is a cam follower, moves onto the cam surface 20c. As a result, the main arm 22 and the auxiliary arm 23 are shifted toward the cassette case 1 by about 3 mm by the coil spring 29, and the pin 26 of the auxiliary arm 23 is fitted into the square hole 9 in the front drilled in the lid 3. match. When the cassette case 1 is subsequently pushed to the right in FIGS. 3 to 5, the auxiliary arm 23 uses the joint with respect to the main arm 22 as a fulcrum and moves against the coil spring 25 at a second stopper (not shown). The lid body 3 is rotated clockwise to the regulated position indicated by the chain line in FIG. Furthermore, when the cassette case 1 is pushed in,
The main arm 22 rotates clockwise together with the auxiliary arm 23 as shown by the imaginary line in FIG. 5, pushing up the lid 3 to an angle that does not hinder the removal of the disk 4 and holding it in the open state. At the end of this pushing process, the cassette case 1 is held by a mechanical flip-flop type locking means (not shown), for example. In this way, this opening/closing means 11
In this case, the lid 3 of the cassette case 1 is opened by an extremely simple operation of just inserting the cassette case 1.

Release the locking means and remove the cassette case 1.
When the lid 3 is pulled out, the lid 3 is closed through an operation opposite to that described above. In that case, the dog 17 is attached to the arm shifter 20 in which the groove 20a of the arm shifter 20 attempts to return to the initial engagement position along its tapered surface.
The arm 1 including the main arm 22 and the auxiliary arm 23 is returned to the initial position by the restoring force of
8 is pushed downward in FIG. 3 by the cam surface 20b of the arm shifter 20 against the coil spring 29, and the pin 26 is removed from the square hole 9.

Next, for reference, the disk transport means 13 will be explained. A chuck member 31 as illustrated in FIG. 6 is attached to the tip of the rotating arm 14 of the disk transport means 13. As shown in FIG. The chuck member 31 includes a pusher 33 that is held movably up and down relative to the frame base plate 32 of the swing arm 14, and a plurality of fingers 34, for example, four fingers, arranged around the pusher 33. There is. The pusher 33 is made of a cylindrical body with a bottom, and has a head 35 in the center thereof extending upward through a through hole bored in the frame board 32 and having an enlarged diameter head 35 at the upper end to prevent the pusher from coming off. A central shaft 36 is provided upright. As is clear from FIG. 8, which shows a bottom view of the pusher 33, a guide groove 45 for arranging the fingers 34 is provided in the body of the pusher 33. A flange 37 is formed at the open end of the pusher 33 and protrudes outward in the radial direction, which serves as a pivot point for the finger, and a coil spring 38 is provided between the pusher 33 and the frame board 32. It has been intervened. As shown in the figure, the head 35 of the pusher 33 is formed with a tapered surface 39 having, for example, an upward slope to the right.
A lift lever 41 having a wedge surface 40 matching the tapered surface 39 is slidably provided. Therefore, the pusher 33 is normally urged downward by the coil spring 38, but by sliding the lift lever 41 to the left in FIG.
It is lifted upward by the vertical component force when it comes into contact with 9. Although not shown, the swing arm 14 includes the lift lever 41.
A driving means such as a solenoid is provided for sliding the.

Each of the fingers 34 is disposed within a guide groove 45 of the pusher 33 and is tightened by a ring spring 42 that is expandable and retractable in the radial direction.
In this case, the ring spring 42 is arranged above the flange 37 of the pusher 33 which is urged downward by the coil spring 38, and therefore the lower end 34a of each finger 34 is aligned with the central axis of the pusher 33. As a reference, it will be biased radially outward, while the upper end 34b will be biased radially inward. As illustrated in FIG. 7, the lower end 34a of the finger 34 is formed into a knife edge shape, and a U-shaped groove 34c that engages with the inner edge of the center hole of the disk 4 is provided near the lower end 34a. There is. Upper end 3 of finger 34
4b extends upward through an opening 44 formed in the frame substrate 32 and is bent inward in a hook shape, and the bent top portion is provided on the lower surface of the cover member 43. protrusion 43
The finger 34 is held in an upright state by slidingly contacting the finger 34 and having its end surface abut against the upper surface of the frame substrate 32. Further, a receiving groove 34d for locking the ring spring 42 is provided on the outer surface of the finger 34, and on the other hand, a receiving groove 34d is provided on the inner surface of the finger 34 at a position higher than the receiving groove 34d. a tapered surface 34 that slopes radially outward toward the
e is formed.

A skirt-like cover 46 is provided around the chuck member 31, as illustrated in FIG. A driven ring 47 is arranged to lightly press the disc 4 from above when playing. This driven ring 47 has a flange portion 47a whose diameter is enlarged so as not to slip out from the opening of the cover 46, and a race member 49 having a ball bearing 48 is placed on the upper surface side of the flange 47a. This lace member 49
A coil spring 50 is interposed between the frame board 32 and the frame board 32.

The operation of this chuck member 31 will be explained in connection with FIG. It is assumed that the cassette case 1 is opened in advance by the arm 18 of the cassette case opening/closing means 11 as described above.

When the swing arm 14 is brought to the disk removal position, that is, above the inner collection chuck 5 of the case base plate 2, and lowered, the lower end 34a of each finger 34 enters between each elastic piece 6 of the inner collection chuck 5. At the same time, the pusher 33 comes into contact with the upper surface of the inner collector chuck 5. Due to its shape, the inner collection chuck 5 loses its restraining force on the disk 4 because each elastic piece 6 bends inward and contracts in diameter when a pressing force is applied upward. An appropriate pressing force for the inner collection chuck 5 is approximately 0.4 kg. moreover,
When the swing arm 14 descends, the lower end 34a of the fingers 34 comes into contact with the inner edge of the center hole of the disk 4, and each finger 34 is forcibly displaced radially inward against the ring spring 42 and moves into the center hole. enter in. And the knife edge shaped lower end 3
When 4a passes over the inner edge of the center hole of disk 4,
Each finger 34 is urged to expand radially outward by the tightening force of the ring spring 42, and the groove 3
4c firmly engages with the inner edge of the center hole of the disk 4. Then, when the swing arm 14 is raised,
The disk 4 is removed from the inner collection chuck 5 while being held by the fingers 34, and placed on the turntable 12 by rotating the arm 14 at a predetermined angle. The constraint is solved as follows. That is, when the swing arm 14 is lowered and the disk 4 is placed on the turntable 12, the lift lever 41 slides to the left in FIG.
By the pressing action of 0, the pusher 33 resists the coil spring 38 and is lifted to a height position where its flange 37 faces the tapered surface 34e of the finger 34. As a result, each finger 34
As shown in FIG. 9, due to the diameter reduction action of the ring spring 42, the lower ends 34a of the ring springs 42 are tilted toward the center, thereby releasing the restraining force on the disk 4. Therefore, even if the turntable 12 is rotated, each finger 34 and the turntable 12
There is no interference between the two. In this case, disk 4
Since it is lightly pressed down by the above-mentioned driven ring 47, there is almost no possibility that slips or the like will occur between the disc 4 and the turntable 12, and a stable playing condition can be obtained.

At the end of the performance, the lift lever 41 slides to the right, and the pusher 33 releases the coil spring 3.
8 to the initial state shown in FIG. 6, and the disk 4 is held by each finger 34. Thereafter, the disk 4 is carried into the cassette case 1 by the rotating arm 14 and fitted into the inner collet chuck 5, but in this case,
Each finger 34 is lifted with the pusher 33 being pulled upward by the lift lever 41 and in an inclined state as shown in FIG. The pressing force of the driven ring 47 not only acts to press the disc 4 onto the turntable 12 during performance, but also conveniently acts when the disc 4 is fitted into the inner collection chuck 5.

In this playback device, the turntable 12 includes a disk 4 with each finger 34 released.
A disk relay 52 is provided for accurately centering the turntable 12 with respect to the turntable 12. As illustrated in FIGS. 9 and 10, the disc relay 52 is a perfect circle that is rotatably held by a bearing pin 54 in a circular recess 53 bored in the center of the turntable 12. The disk 52a has a circular plate 52a, on which a plurality of claws 52b are arranged in an annular manner at equal intervals so as to fit into the center hole of the disk 4. In this case, the arrangement and shape of the fingers 34 and claws 52b are important, and it is necessary to prevent them from coming into contact with each other on their surfaces and causing blocking during the downward movement of the chuck member 31. Therefore, in this invention, the claw 5
The tip of the finger 34 is formed into a sharp knife edge with a diameter of about 0.05 to 0.1 mm, for example, like the lower end 34a of the finger 34, and in order to prevent the finger 34 and the claw 52b from coming into contact with each other at two or more points at the same time. If there are four fingers 34 arranged at equal intervals, seven claws 52a are arranged at equal intervals, and if there are five fingers 34, eight claws 52b are arranged at equal intervals (both are arranged at equal intervals). So, 2
Points or more are prevented from having the same phase angle.

Next, the disk transport means 13 and its operation control system will be explained with reference to FIGS. 2 and 11. In FIG. 11, point C is the position at which the disk 4 is taken out from the inner collection chuck 5, point D is the center position of the turntable 12, and point F
indicates the rotation center position of the rotation arm 14.

The disk transport means 13 includes a drive gear 61 connected to, for example, a low-speed rotating motor, and a driven gear 62 that meshes with the drive gear 61. In this case, the gear ratio between the drive gear 61 and the driven gear 62 is 1:2, and the rotation axis of the driven gear 62 is placed on the rotation center position F of the swing arm 14. That is, in this embodiment, the swing arm 14 is attached to a pair of brackets 6 with respect to a disc seat 63 rotatably provided on the base 15.
4, 64 and a bearing pin 65 installed horizontally thereon, the driven gear 62 is rotatably fitted around the disk seat 63 as a bearing. .

Although not shown, a counterweight is attached to the rear end of the swing arm 14, and the counterweight holds the tip of the swing arm 14 at a predetermined height in normal conditions. .

A crankcase 66 that rotates integrally with the drive gear 61 is attached to the drive gear 61. Inside the crankcase 66 is a slider 68 having a crank pin 67 extending in the vertical direction, and a slider 68 that is always rotated in the radial direction. A timing spring 69 that biases outward is housed. On the other hand, the swing arm 14 has a long hole 70 extending in the longitudinal direction, and a slider 71 having a bearing hole into which the crank pin 67 is fitted is slidably provided in the long hole 70. ing. The crank pin 67 is attached to the slider 68 via a bearing member (not shown) so that it always faces vertically even when the swing arm 14 moves up and down.
In this way, the pivot arm 14 is connected to the crank pin 67.
It is connected to the drive gear 61 via a crank mechanism including a crank mechanism, and is driven to swing around point F. On the base 15, there is a first stopper 72 that stops the swing arm 14 at the point C position. , and a second stopper 73 for stopping at the D point position.

Three cams are provided on the driven gear 62 to push up a roller 75 attached to the rear end of the swing arm 14 and lower the chuck member 31 at the tip end of the swing arm 14 to a predetermined position. That is, the first cam 76 lowers the swing arm 14 to take out the disk 4 at point C.
Then, at point D, the rotating arm 14 is lowered to place the disc 4 on the turntable 12.
cam 77 and a third cam 78 for storing the disk 4 in the cassette case 1 at point C. In this case, the first cam 76 and the third cam 78 are 180 degrees apart from each other. It's separated,
The second cam 77 is arranged so as to act on the roller 75 on the line connecting points C and F, while the second cam 77 is arranged so as to act on the roller 75 on the line connecting points D and F.

Note that, unlike this embodiment, the roller 75 is provided not on the rear end side of the swing arm 14 but on the front end side of the bearing pin 65, and a recess is provided in the portion where the first to third cams are provided. It is also possible to form a swiveling arm 14 and deform such that the tip thereof descends at a predetermined position due to the weight of the swiveling arm 14.

One cycle operation of the swing arm 14 by the above mechanical control system will be explained. Incidentally, the rotation locus of the crank pin 67 is shown by an imaginary line in FIG. Further, the standby position of the swing arm 14 before the lid 3 of the cassette case 1 is opened is at point D, that is, on the turntable 12, and the crank pin 67 is located between points m and p.

When the lid 3 of the cassette case 1 is opened by the cassette case opening/closing means 11, the drive gear 61 rotates clockwise in FIG. It is moved from point C towards point C. In this case, the crank pin 67 moves in an arc from point m to point n, which intersects the CF line, and when it reaches point n, the swing arm 14 comes into contact with the first stopper 72. Therefore, the crank pin 67 moves linearly within the elongated hole 70 from point n toward point o on the CF line. in this way,
While the crank pin 67 moves from point n to point o, the swing arm 14 remains at point C, but the driven gear 6
2 is continuously rotating in the counterclockwise direction in FIG. He is lowered onto the inner collect chuck 5 and grabs the disk 4.
Then, when the first cam 76 passes below the roller 75, the tip side of the swing arm 14 rises again to its original height position. Thereafter, the crank pin 67 moves from point O to point P while drawing an arc, and along with this, the swing arm 14 moves to point D.
is moved onto the turntable 12 of. When the swing arm 14 comes into contact with the second stopper 73, the crank pin 67 moves linearly in the elongated hole 70 from point p toward point m on the DF line, and the second cam 77 moves straight on the DF line. Then, the roller 75 is pushed up, and as a result, the tip side of the swing arm 14 is lowered, and the disk 4 is placed on the turntable 12. At this point, the rotation of the drive gear 61 is stopped, and a rotation command signal is output to the turntable 12 to start playing. When the performance ends and the drive gear 61 rotates again, the second cam 7
7 and the roller 75 are released, the tip end of the swing arm 14 returns to a predetermined height position. Next, the swing arm 14 is moved toward point C, and at that position, its tip side is lowered onto the inner collect chuck 5 by the third cam 78 to transfer the disk 4 to the inner collect chuck 5. . After that, the swing arm 14 rises,
It is then returned to point D to wait for the next performance.

As is clear from the above description of the embodiment, this invention has a pin at its tip that can be fitted into the square hole of the lid of the cassette case, and an arm that extends parallel to the insertion/removal direction of the cassette case. , a bearing member that pivotally supports the other end of the arm so that the tip end of the arm can rotate in an imaginary vertical plane perpendicular to the base including the cassette case mounting part; and a bearing member inserted into the cassette case mounting part. a dog that is rotated in contact with the front surface of a cassette case; and an arm shifter that is rotatable together with the dog and that selectively shifts the arm between a non-engaging position and an engaging position with respect to the lid body. When the dog rotates by a predetermined angle, the arm is shifted to the engagement position by the arm shifter to fit the pin into the square hole and push the pin into the cassette case. It is characterized by the fact that it rotates around the bearing member while being lifted from the case base plate by receiving force. Therefore, it can be applied as is to current general-purpose cassette cases.
This is extremely convenient for both manufacturers and users.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a current general-purpose cassette case in an open state, Fig. 2 is a schematic perspective view showing an embodiment of the playback device according to this invention, and Fig. 3 is a main part of the cassette case opening/closing means. FIG. 4 is a schematic side view thereof, FIG. 5 is an explanatory diagram of the operation of the cassette case opening/closing means, FIG. 6 is a vertical sectional view showing the main parts of the chuck member, and FIG. 7 is a schematic side view thereof. is a side view of the finger applied to the chuck member, FIG. 8 is a bottom view of the pusher, FIG. 9 is a schematic longitudinal sectional view showing the operational relationship between the finger and the disc relay of the turntable, and FIG. 10 is a side view of the finger applied to the chuck member. 10a is a plan view of the disk relay, FIG. 10b is a vertical sectional view showing a part thereof, and FIG. 11 is a plan view schematically showing the disk conveying means. In the figure, 1 is a cassette case, 2 is a case board,
3 is a lid body, 4 is a compact disk, 5 is an inner collection chuck, 6 is an elastic piece, 8 is a flange,
9 is a square hole, 11 is a cassette case opening/closing means, 12
1 is a turntable, 13 is a disk conveyance means, 1
4 is a rotating arm, 15 is a base, 17 is a dog, 1
8 is an arm, 20 is an arm shifter, 22 is a main arm, 23 is an auxiliary arm, 29 is a coil spring, 31 is a chuck member, 32 is a frame member,
33 is pushsha, 34 is finger, 35 is head,
38 is a coil spring, 39 is a tapered surface, 40
is a wedge surface, 41 is a lift lever, 42 is a ring spring, 45 is a guide groove, 47 is a driven ring, 52 is a disc relay, 61 is a drive gear, 62 is a driven gear, 66 is a crank case, 67 is a crank pin, 70 is a The long holes, 72 and 73 are stoppers, 75 is a roller, and 76 to 78 are cams.

Claims (1)

[Claims for Utility Model Registration] (1) It has a case substrate and a lid pivotally attached to the case substrate so as to be openable and closable, and the case substrate has a lid that is elastically deformed and frictionally attached to the center hole of the compact disk. A cassette case, which is provided with a fitting inner collet chuck and square holes are bored in both side walls of the lid, is inserted into and removed from the cassette case mounting portion on the base side inside the device. A compact disk playback device having a cassette case opening/closing means that automatically opens and closes during the playback process, wherein the cassette case opening/closing means has a pin at its tip that can be fitted into a square hole of the lid, and the cassette case opening/closing means an arm extending parallel to the insertion/removal direction, and the other end of the arm being pivotally supported so that the distal end of the arm can rotate within an imaginary vertical plane perpendicular to the base including the cassette case mounting section. a bearing member, a dog that is inserted into the cassette case mounting portion and rotates in contact with the front surface of the cassette case; and a dog that is rotatable together with the dog and that moves the arm to a non-engaging position with respect to the lid body. and an arm shifter that selectively shifts the pin to the engagement position, and when the dog rotates a predetermined angle, the arm is shifted to the engagement position by the arm shifter to move the pin into the square hole. 1. A compact disk playback device, wherein the compact disk playback device is configured to rotate about the bearing member while being inserted into the cassette case and lifting the cover from the case base plate in response to a pushing force against the cassette case. (2) In claim (1) for utility model registration, the arm includes a main arm that is pivotally supported by the bearing member, and an auxiliary arm that is articulated at the rotating end side of the main arm and that has the pin at the tip. 1. An apparatus for playing a compact disc, characterized in that the auxiliary arm is normally held by the main arm so as to have a predetermined angle of elevation with respect to the insertion direction of the cassette case. (3) In claim (1) of the utility model registration, the dog is characterized in that it has an engaging end that engages with a peripheral flange of the case board to suppress vertical movement of the case board. Compact disc playback device. (4) In claim (1), the arm shifter includes a first cam surface that holds the arm in a non-engaged position with respect to the lid, and a second cam that shifts the arm to an engaged position. 1. A compact disc playback device, comprising a surface and a groove that engages with a stopper pin to hold the dog at an initial position. (5) In claim (1) or (2), the bearing member biases the arm toward the engaging position with respect to the cassette case, and biases the arm toward the standby position. A compact disk playback device characterized by being equipped with a spring that biases rotation. (6) In claim (2) of the utility model registration, a first stopper is provided on the rotation end side of the main arm to hold the auxiliary arm at a predetermined elevation angle position, and the auxiliary arm is moved from the elevation angle position. 1. A compact disc playback device, characterized in that a second stopper is formed for restricting rotation of the auxiliary arm relative to the main arm when the auxiliary arm is rotated by a specific angle.