JPH051006Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a disc playback device, and particularly to a disc playback device that can be made smaller and thinner.

BACKGROUND TECHNOLOGY There are generally known playback devices that are equipped with a small disk on which information signals are recorded and play back the disk using an optical pickup. A method has been proposed in which the disc is placed in a case and the small disc is transported to the playback device along with the case. In addition, the attachment/detachment mechanism for attaching the case to a predetermined position within the playback device has generally had a structure in which the case is first horizontally inserted into a position on the spindle and then moved vertically toward the spindle.
That is, in the conventional playback apparatus, the case was moved stepwise in two directions by an attachment/detachment mechanism, and the optical pickup and spindle were fixed within the playback apparatus.

However, in the conventional playback device described above, it was necessary to move the case stepwise in two directions in order to mount the small disk in a predetermined position, so a large moving space had to be secured within the playback device, and the device The problem was that it became too large. In addition to this, the structure of the attachment/detachment mechanism becomes complicated in order to move the case stepwise in two directions.
This also has the problem of increasing the size of the playback device.

Conventionally, therefore, a disk playback device has been proposed in which the case is moved in one direction during mounting and removal, and the optical pickup, spindle motor, etc. are movable, thereby reducing the size of the device.

The specific configuration of the conventional device is that the above-mentioned optical pickup, spindle motor, etc. are attached to a movable base, and by displacing this movable base toward the disk, the optical pickup, spindle motor, etc. are moved to a predetermined playback position. It was designed to allow

In addition, as a mechanism for displacing the movable base, there are, for example, mechanisms that utilize a rotating cam or mechanisms that utilize a rack and pinion mechanism.

Problems to be Solved by the Invention As is well known, when playing a disc using an optical pickup, it is necessary to position the optical pickup with respect to the disc with high precision.

However, in the configuration using a rotating cam or rack-and-pinion mechanism as described above, an expensive stepping motor and drive control of this stepping motor are required in order to move and stop the movable base at a predetermined playback position. It is necessary to provide a control device to
There was a problem that the product cost increased.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a disc playback device that can facilitate movement control of a movable base and reduce costs.

Means for Solving the Problems In order to solve the above problems, the present invention provides a mounting method in which a case in which a disk is housed is displaced horizontally in one direction with respect to a fixed base, and the case is mounted and removed at a predetermined mounting position. a movable base which is provided with a disc reproducing means and a disc driving means and which is rotatably attached to the fixed base; and when the disc is regenerated, the disc reproducing means moves the movable base to face the disc; A movable base driving means for rotationally displacing the movable base to a predetermined playback position where the drive means engages with the disk, and for rotating the movable base in a direction in which the movable base is moved away from the playback position when the disk is ejected. In the playback device, a rotation support shaft is provided at one end of the movable base for movably supporting the movable base relative to the fixed base, and an engagement pin is provided at the other end, and the movable base driving means is provided on the opposite side of the rotation support shaft via the lower movable base, and is configured to be displaceable in parallel to the rotation support shaft in a plane parallel to the horizontal plane of the fixed base, and the movable A guide groove is formed in the base driving means, and includes an upper horizontal guide groove, a lower horizontal guide groove, and an inclined guide groove that connects the upper horizontal guide groove and the lower horizontal guide groove. This is characterized by a configuration in which a dowel pin is engaged.

Embodiment Next, an embodiment of the disc playback device (hereinafter referred to as playback device) according to the present invention will be described.

As shown in FIGS. 3 to 5, the playback device 1 generally includes a fixed base 2, a movable base 3, a lock mechanism 4, a movable base drive mechanism 5, an optical pickup 6, an optical pickup drive mechanism 7, and an optical pickup drive mechanism. It is composed of a displacement regulating mechanism 8 (hereinafter referred to as displacement regulating mechanism), etc., and is used to reproduce signals recorded on the small disk 9 by attaching a case 10 containing a small disk 9 shown in FIG. .

First, the configuration of the case 10 attached to the playback device 1 will be explained using FIG. 6. The case 10 includes a case body 10a and a lid 10b for opening and closing the case body 10a. A storage recess 11 for storing the small disk 9 is formed at the center of the case body 10a. In addition, a small disk 9 is provided on the bottom of the storage recess 11.
Insertion port 1 into which the turntable that rotates the
2 and an opening 13 formed at a position facing the optical pickup 6. This opening 1
3 is closed by a shutter 14 except during playback (the figure shows the opening 13 in an open state) to prevent dust and the like from entering. Shutter 1
4 is operated by operating a shutter lever 15 provided on the side of the case body 10a. Further, a stabilizer 16 is provided at a predetermined position facing the insertion opening 12 of the lid body 10b. Furthermore, knobs 18a and 18b are provided on one side of the case body 10a to engage with claws 17a and 17b formed on the lid 10b to lock the lid 10b in the closed position. The small disk 9 is attached to the storage recess 11 of the case body 10a, and is inserted into and removed from the playback device 1 with the lid 10b closed.

The playback device 1 is provided with a locking mechanism 4, a loading cover 19, etc. on the upper surface of a fixed base 2, as shown in FIG. 2
It is inserted into the playback device 1 from 0. Loading rails 21 are provided on both sides of the loading cover 19.
a, 21b are provided, and the case 10 is inserted in the direction of arrow _Y2 in the figure with both sides guided and held by the loading rails 21a, 21b. Further, on the upper surface of the loading cover 19, there is a misinsertion prevention lever that allows insertion of the case 10 only when the case 10 is inserted properly, and engages with the case 10 when it is not inserted properly to prevent misinsertion. 22
Opening/closing levers 23a, 23b are provided which engage with the shutter lever 15 provided on the case 10 and the case 10 to open and close the shutter 14.

A slider 24 is provided at the front of the loading cover 19 in the case insertion direction. The slider 24 is formed by bending a plate material into a substantially Z shape,
It is configured to be movable relative to the fixed base 2 in the directions of arrows Y ₁ and Y ₂ in the figure. This slider 24 is connected to rollers 25a and 25 provided on the fixed base 2.
It moves while being guided by the upper plate portion 24a and the loading cover 19, and is always biased in the direction of arrow _Y1 in the figure by coil springs 26a and 26b stretched between the upper plate portion 24a and the loading cover 19. case 10
passes through the loading cover 19 and the slider 2
4, the tip surface of the case 10 is connected to the slider 24.
The wall portion 24b formed by bending the
(shown in FIG. 5) and presses it. As a result, the slider 24 is connected to the coil spring 26.
It is displaced together with the case 10 in the direction of arrow _Y2 in the figure against the elastic force of the elements a and 26b. Further, at approximately the center position in FIG. 4 of the lower plate portion 24c of the slider 24, there is a
A lock pin 27 is implanted which engages with the lock mechanism 4 and locks the slider 24 when the case 10 is inserted to a predetermined mounting position. In addition, roller 25
a and 25b guide the slider 24 and come into contact with the side of the case 10 to be inserted, so that they also function to guide the insertion of the case 10.

The lock mechanism 4 includes a lock lever 28, a switch lever 29, a set lever 30, and a switch 3.
1, a set spring 32, etc. This lock mechanism 4 locks the slider 24 by engaging a lock pin 27 with a claw 28a formed on a lock lever 28, thereby placing the case 10 (that is, the small disk 9) in a predetermined position in the playback device 1. Position and install.

The lock lever 28 is rotatably provided on a support shaft 33 erected on the fixed base 2, and a switch lever 29 and a switch 31 are attached to the upper surface of the lock lever 28. The switch lever 29 is a substantially semicircular plate member, and is rotatably provided on the support shaft 33, so that the switch lever 29 can slide and rotate on the lock lever 28. The switch 31 is fixed to the right side of the lock lever 28, and its switch knob 31a engages with a protrusion 29a formed on the switch lever 29. The lock lever 28 is always urged to rotate clockwise by the spring 34, while the switch lever 29 is urged counterclockwise by the pressing force of the switch knob 31a. Lever 2
Rotation is restricted at a predetermined position by engagement with a long hole 29b formed in 9. In this state, the claw part 2
8a is configured to protrude slightly from the side end of the switch lever 29. Further, the switch 31 is configured such that its switch knob 31a is tilted to the left, and when the switch knob 31a is tilted to the right against this, the switch 31 is closed.
The set lever 30 is rotatably supported by the roller 25a, and a set spring 32 is stretched between its tip and the lock lever 28. Further, the set lever 30 is provided with an abutting portion 35 that comes into contact with and presses the case 10 to be inserted.

The locking mechanism 4 is in the unlocked state in FIG. 4, and in this state the slider 24 is in the Y ₂
It does not lock even if you move in the direction.

That is, when the case 10 is not inserted, the set lever 30 is rotatable.
Therefore, the lock lever 28 is rotated clockwise by the spring 34. Therefore, the claw portion 28a is retreated to the left from the locus of movement of the lock pin 27 (moves in the _Y2 direction) as the slider 24 moves, and the lock pin 27 is not locked by the lock mechanism 4. This results in case 1
When 0 is not inserted, playback device 1
Even if an external force is applied to the slider 24 and the slider 24 moves, or even if a rod-shaped member is inserted through the insertion opening 20 and presses the slider 24 due to a child's mischief, the slider 24 will move. 24 is not locked and the playback device 1 is not locked even though the case 10 is not inserted.
It is reliably prevented from entering the regenerating state.

On the other hand, when the case 10 is properly inserted, the case 10 comes into contact with the contact portion 35 and presses it. This causes the set lever 30 to rotate counterclockwise, thereby forcing the lock lever 28 to rotate counterclockwise via the set spring 32. Since the elastic force of the set spring 32 is selected to be greater than the elastic force of the spring 34, the lock lever 28 rotates counterclockwise, and the claw portion 28a
reaches the locus of movement of the lock pin 27 (the position indicated by the dashed line in the figure), and the lock mechanism 4 enters the standby state. When the lock mechanism 4 is in the standby state, when the slider 24 moves in the _Y2 direction together with the case 10,
The lock pin 27 comes into contact with the claw portion 28a, climbs over it, and engages with the lock lever 28, so that the slider 24 is locked. Further, when the lock pin 27 passes over the claw portion 28a, the lock pin 27 rotates the switch lever 29 clockwise. As a result, the switch knob 31a of the switch 31 is tilted to the right, the switch 31 is closed, and the movable base drive mechanism 5, which will be described later, is started.

When the small disk 9 housed in the case 10 is attached to and removed from a predetermined position of the playback device 1, it should be noted that the case 10 moves only in the Y ₁ and Y ₂ directions. This simplifies the structure of the mechanism for attaching and detaching the case 10, and eliminates the need to displace the case 10 in the Z ₁ and Z ₂ directions in the figure while maintaining the operating state of the shutter lever 15 that opens and closes the shutter 14. Malfunctions can be prevented. In addition, since the case 10 is configured to move only in the Y ₁ and Y ₂ directions in the figure and not in the Z ₁ and Z ₂ directions,
In this embodiment, the movable base 3 includes an optical pickup 6,
Optical pickup drive mechanism 7, spindle motor 3
6, etc., and these are moved towards the case 10 (small disk 9) during playback.

Next, the lock plates 24d and 24e attached to the slider 24 will be explained using mainly FIGS. 4 and 10. In addition, Figure 10 is the 4th
A cross section taken along the line XX in the figure is shown. Lock pins 24 are attached to the lock plates 24d and 24e.
d _-1 and 24e _-1 are installed, and slider 2
It is rotatably supported on support shafts 33a and 33b provided at 4. This lock plate 24d, 2
Coil springs 26c and 26d are installed at the top of 4e.
are connected, and the lock plates 24d, 24
In FIG. 10, e is normally biased to rotate clockwise (therefore, it is normally in the state shown in FIG. 10A).

On the other hand, lock holes (not shown) are formed at both front sides of the bottom surface of the case 10. These lock holes are configured so that lock pins 24d _-1 and 24e -1 installed in lock plates 24d and _24e can be fitted therein. Case 10 has lock plate 24
d and 24e are rotated, and the lock pins 24d _-1 ,
24e _-1 engages with the lock hole, as shown in the figure.
Displacement in the Y ₁ and Y ₂ directions is regulated.

The operation of the lock plates 24d and 24e will now be explained. In FIG. 10A, the case 10 is inserted through the insertion port 20, and its tip end is attached to the slider 24.
The state immediately after contact with the wall portion 24b is shown. In this state, the lock plate 24d,
24e has been rotationally displaced clockwise and has retreated into the opening 2a formed in the fixed base 2. When the case 10 is further inserted in the _Y2 direction from this state, the slider 24 also moves in the _Y2 direction together with the case 10. Then, as the lock plates 24d and 24e move, the back surfaces of the lock plates 24d and 24e move to the edge 2a of the opening 2a.
a _-1 and relatively lock plate 24d,
24e is biased to rotate counterclockwise, as shown in FIG. 10B.
As shown in FIG. 2, the lock pins 24d _-1 and 24e _-1 fit into lock holes formed in the bottom surface of the case 10.
This prevents unnecessary displacement of the case 10 in the Y ₁ and Y ₂ directions, and prevents the case 10 from separating from the playback device 1 even if an attempt is made to pull out the case 10 in the Y ₁ direction in the locked state. It is possible to prevent unexpected accidents. Also, the lock plates 24d and 24e are connected to the slider 24.
Therefore, even if the case 10 is inserted at an angle, the slider 24 is provided in the case 1.
Therefore, the lock pins 24d _-1 and 24e _-1 can always fit into the lock holes.

Here, the movable base 3 and each component provided thereon will be explained using mainly FIGS. 1 and 3. The movable base 3 is provided on the back surface of the fixed base 2, and shaft bearing parts 37a and 37b protruding from both sides of the left end in FIG. brackets 38a, 38b (shown in Figure 4)
The bearing is mounted on the shaft. Therefore, the movable base 3
It is configured to be rotatable in the directions of arrows A ₁ and A ₂ in the figure. This movable base 3 is moved in the _A1 direction by a movable base drive mechanism 5, which will be described later, when playing the small disk 9 (shown in FIG. 2).
When ejecting (when removing the case 10 shown in FIG. 1), it is moved in the _A2 direction.

Optical pick-up 6 is optical pick-up base 39
Y ₁ , Y ₂ relative to the movable base 3 by the movable base drive mechanism 7 composed of a linear motor 42, etc.
(In FIG. 3, the optical pickup 6 is fixed to the back surface of the optical pickup base 39.) The optical pickup base 39 has an opening 4 formed in the movable base 3.
0 is supported on sliding shafts 41a and 41b installed horizontally, and is displaced in the Y ₁ and Y ₂ directions using a linear motor 42 as a drive source, and the information recorded on the small disk 9 Read. Further, a spindle motor 36 is provided at a predetermined position on the movable base 3.

Next, the movable base drive mechanism 7 will be explained.
The movable base drive mechanism 7 is roughly referred to as the movable base 3.
The base pins 42a and 42b are implanted near both sides of the end in the _Y1 direction, and the guide shaft 43 is provided horizontally across the fixed base 2, so that the base pins _42a and 42b are slidable in the directions of arrows X1 and _X2 in the figure. It is composed of an elevator member 44, a motor 45 serving as a driving source, and the like. The rotation of the motor 45 is transmitted to a rack 48 provided on the elevator member 44 via gears 46 and 47, and therefore, the elevator member 44 moves in the directions of arrows X ₁ and X ₂ in the figure depending on the direction of rotation of the motor 45. This motor 45 is connected to a switch 31 (shown in FIG. 4) which is closed when the lock mechanism 4 is in the locked state, in other words, when the case 10 is installed at a predetermined mounting position.
It is started by. The elevator member 44 is a plate-like member, and is provided with brackets 49 and 50 at two locations on the left and right sides through which the guide shaft 43 is inserted. The bracket 50 also functions as a component of displacement regulation means 8, which will be described later.

Here, FIG. 7 shows the BB arrow view in FIG. 3. Note that in FIG. 7, illustration of the rack 48 is omitted. As shown in the figure, the elevator member 44
Resin plates 51a, 51 with good slipperiness are provided on both sides of the
b is attached, and these resin plates 51a, 51
Cam grooves 52a and 52b are formed in the grooves 52a and 52b, which are inclined diagonally upward toward the left. This cam groove 5
2a, 52b are the upper horizontal guide groove portions 52a _-1 . 5
2b _-1 and the lower horizontal guide groove portion 52a _-3 . 52b _-3 and
Upper horizontal guide groove portion 52a _-1 . 52b _-1 and lower horizontal guide groove 52a _-3 . 52b _-3 is continuous with the inclined guide groove portion 52a _-2 . 52b _-2 . In addition, the movable base 3 is provided in the cam grooves 52a and 52b.
Base pins 42a and 42b implanted in are inserted and engaged. Now consider the case where the motor 45 rotates and the elevator member 44 moves in the direction of arrow _X2 .
As the elevator member 44 moves in the _X2 direction, the base pins 42a, 42b are guided by the cam grooves 52a, 52b and are relatively displaced, and along the inclination, the base pins 42a, 42b move toward the lower horizontal guide groove portion 52a _-3 . 52b _-3 to the inclined guide groove portion 52a _-2 . 52b _-2 , and further to the upper horizontal guide groove portion 52a _-1 . 52b _-1 . As a result, the movable base 3 is rotationally displaced in the direction of arrow _A1 in FIG. It is displaced toward disk 9. and base pin 42a,
42b reaches the left end of the cam grooves 52a, 52b, the playback device 1 engages the spindle motor 36 with the small disk 9 inside the case 10, and starts the optical pickup, as shown in FIGS. 6 is in a reproduction state in which it faces the small disk 9 at a predetermined distance. Note that when the playback device 1 is in the playback state, the lever portion 4 formed on the elevator member 44
4a operates a switch 55 provided on the fixed base 2 as the motor 4a moves.
5 is stopped, and the movement of the elevator member is stopped.

As described above, the case 10 containing the small disk 9 is installed and removed by moving it horizontally in the Y ₁ and Y ₂ directions with respect to the fixed base 2,
In addition, an optical pickup 6, a spindle motor 36, etc. are provided on the movable base 3, and this is rotatably attached to the fixed base 2, so that the movable base 3 is displaced toward the small disk 9 during playback. The movement space of each component to be driven and displaced can be made small, and furthermore, by providing the rotary shaft of the movable base 3 protruding above the surface of the fixed base 2, the playback device 1 can be made smaller and thinner. be able to. Furthermore, by having the above configuration,
The height control of the reproducing position and non-reproducing position of the movable base 3 is facilitated both mechanically and electrically, and costs can be reduced. That is, according to the above configuration, if the dimensions of the elevator member 44 and the cam grooves 52a, 52b, etc. formed therein are formed with a predetermined precision, the heights of the regeneration position and the non-regeneration position of the movable base 3 can be adjusted. is determined by the precision of these parts, so control for horizontally displacing and driving the elevator member 44 can be performed relatively easily, and detection of the amount of displacement of the elevator member 44 does not require much precision. Therefore, it is possible to move the movable base 3 up and down with high precision with a simple and low-cost configuration. Note that a plurality of positioning protrusions 53 are provided on the upper surface of the movable base 3, and as shown in FIGS. 2 and 8, when the playback device 1 is in the playback state, each positioning protrusion 53
and push it up to fix the case 10 to the base 2 and loading rails 21a, 2.
Separate from 1b. As is well known, the distance between the optical pickup 6 and the small disk 9 during playback must be set with high precision. Each positioning projection 53 is provided on the movable base 3, and the optical pickup 6 is also provided on the movable base 3. Therefore, by appropriately selecting the protruding dimensions of the positioning protrusions 53, when each positioning protrusion 53 pushes up the case 10 during playback, the distance between the case 10 (small disk 9) and the optical pickup 6 is automatically set to a predetermined value. Set to dimensions. Further, the loading cover 19 is provided with leaf springs 54a and 54b that urge the case 10 in the _Z1 direction, and the above-mentioned predetermined spacing is also maintained thereby.

Next, the displacement regulating means 8 will be explained using mainly FIGS. 3 and 9. The displacement regulating means 8 is generally composed of a lock arm 56, a locking pin 57, the above-mentioned bracket 50, and the like. The lock arm 56 has one end rotatably supported on the movable base 3 and the other end connected to the bracket 50. Further, a large number of engagement grooves 56a are formed in the side portion of the lock arm 56 over a predetermined length range. Further, a locking pin 57 is installed on the optical pickup base 39 facing the engagement groove 56a. As described above, the bracket 50 is provided on the elevator member 44, and the guide shaft 43 is inserted through the left and right arm portions 50a, 50b, respectively. A sliding member 58, which is also slidably attached to the guide shaft 43, is disposed between the arms 50a and 50b, and one end of the lock arm 56 is connected to the sliding member 58. ing. This sliding member 58 and both arm parts 50
Coil springs 59 are provided between a and 50b, respectively.
a and 59b are inserted through the guide shaft 43.

When the playback device 1 is in the ejected state, the elevator member 44 is moved in the _X1 direction, as shown in FIG. Bracket 50 too
The sliding member 58 is at the position moved in the _X1 direction and is biased in the _X1 direction by the coil spring 59b. This biasing force causes the lock arm 56 to move toward the support shaft 6.
0 as the rotation center and rotate counterclockwise to engage the engagement groove 5.
6a and the locking pin 57 are engaged, and the movement of the optical pickup base 39 is restricted.

On the other hand, when the reproducing apparatus 1 enters the reproducing state, the bracket 50 together with the elevator member 44 moves in the _X2 direction from the state shown in FIG. 3, resulting in the state shown in FIG. 9. In this state, the bracket 50 is moved in the _X2 direction, so the coil spring 59
a biases the sliding member 58 in the _X2 direction, and this biasing force causes the lock arm 56 to move toward the support shaft 6.
Rotate clockwise around 0 as the rotation center. As a result, the lock arm 56 is separated from the locking pin 57, the optical pickup base 39 becomes movable, and is driven by the optical pickup drive mechanism 7 to perform the regeneration process. Further, when returning from the reproduction state to the eject state, the eject state shown in FIG. 3 is achieved by performing the reverse operation to the series of operations described above.

Effects of the invention As described above, according to the invention, it is possible to control the horizontal displacement of the movable base drive means relatively easily, and the detection of the amount of displacement of the movable base drive means does not require much precision. Therefore, it has features such as being able to move the movable base up and down with high precision with a simple and low-cost configuration.

[Brief explanation of the drawing]

1 and 2 are main part configuration diagrams for explaining the displacement of the movable base of one embodiment of the playback device of the present invention, FIG. 3 is a bottom view of the device of the present invention, and FIG. 4 is a diagram of the main parts of the playback device of the present invention. FIG. 5 is a plan view of the device, FIG. 5 is a side view of the device of the present invention, FIG. 6 is a perspective view for explaining a case that houses a small disk and is inserted into the device of the present invention, and FIG. 7 is a side view of the device of the present invention.
8 and 8 are diagrams for explaining the displacement of the elevator member and the movable base, FIG. 9 is a bottom view of the reproducing apparatus in the reproducing state, and FIG. 10 is a side view for explaining the lock plate. DESCRIPTION OF SYMBOLS 1... Playback device, 2... Fixed base, 3... Movable base, 4... Lock mechanism, 5... Movable base drive mechanism, 6... Optical pick-up, 7... Optical pick-up drive mechanism, 8... Displacement Regulatory measures, 9...
Small disk, 10... Case, 19... Loading cover, 20... Insertion slot, 24... Slider, 27... Lock pin, 28... Lock lever, 28a... Claw portion, 29... Switch lever,
30...Set lever, 31...Switch, 32
...Set spring, 35...Abutment part, 36...
...Spindle motor, 39...Optical pickup base, 42a, 42b...Base pin, 43...
Guide shaft, 44...Elevator member, 4
9, 50... Bracket, 52a, 52b... Cam groove, 53... Positioning protrusion, 56... Lock arm, 56a... Engagement groove, 57... Locking pin, 5
8...Sliding member.

Claims (1)

[Claims for Utility Model Registration] An attachment/detachment mechanism for displacing a case containing a disk in one direction horizontally relative to a fixed base to attach and detach the case to a predetermined attachment position, a disk playback means, and a disk drive means. A movable base is provided and rotatably attached to the fixed base, and when the disc is played, the movable base is held so that the disk playback means faces the disk and the disk drive means engages with the disk. A disk playback device comprising a movable base drive means for rotationally displacing the movable base to a predetermined playback position and moving the movable base in a direction in which the movable base is moved away from the playback position when the disc is ejected. A rotating support shaft is provided at one end of the base to movably support the movable base relative to the fixed base, and an engagement pin is provided at the other end, and the movable base driving means is connected to the lowering base. provided on the opposite side of the rotation support shaft via the movable base drive means, and configured to be displaceable in parallel to the rotation support shaft in a plane parallel to the horizontal plane of the fixed base; A guide groove is formed by an upper horizontal guide groove, a lower horizontal guide groove, and an inclined guide groove connecting the upper horizontal guide groove and the lower horizontal guide groove, and the engagement pin is engaged with the guide groove. A disc playback device characterized in that it has a configuration in which it is combined.