JPH03203065A - Disk clamper - Google Patents

Abstract

PURPOSE:To reproduce both sides of a laser disk under the state of non-contact with an external operation part by constituting the disk clamper to keep a clamper beam and a clamper in noncontact with each other during the reproducing of the laser disk. CONSTITUTION:Under the state for reproducing the A-side 1A of the laser disk, the clamper 72 and the clamper beam 10 are not in contact with each other. The laser disk 1 is centered on the A-side 1A by a tapered part 67a of a taper ring A 67, and is pressed by a clamp ring 84 to a turntable 64. This pressing force is decided by attracting force between a main magnet 82 and an attracting ring 65, and is not dependent upon a compression spring 83. On the other hand, under the state for reproducing the B-side 1B of the laser disk, the beam 10 is slightly raised, whereas the clamper 72 is not in contact with the beam 10. Under this state, a submagnet 85 bonded to a taper ring B 87 is close enough to a yoke 81 of the magnet 82, and because of attracting force of the magnet 85 overcoming resiliency of a compression spring 88, the B-side 1B is self-held accordingly.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a multi-disc player (hereinafter referred to as a disc player) which also serves as a laser disc player, a compact disc (hereinafter referred to as CD), and a compact disc with video (hereinafter referred to as CDV). ) relates to a disk clamp device for concentrically fixing a laser disk to a turntable.

2. Description of the Related Art In recent years, double-sided automatic playback type disc players have become popular, and disc clamping devices developed for double-sided automatic playback have been used.

A conventionally used disk clamp device will be explained below.

10 and 11 show the main drive mechanism of a disc player equipped with a conventional disc clamper device. As shown in FIGS. 10 and 11, the apparatus includes a laser disc 1, a tray 2 for transporting the loaded disc, a tray drive motor 30°, a tray base 36°, a playback motor 3, and a shaft 3S of the motor 3. fixed turntable 4
, a disk clamper 12, and a clamper beam 10 for raising and lowering the disk clamper 12.

It also serves as a horizontal guide for the groove cams 42R, 42L for driving the tray 2 and the clamper beam 10 in the vertical direction, the motor 50 for driving the groove cam 42R, and the groove cam 42R42I.
7L vertical guides 41R411, the bins 39R, 39L are at both ends of the clamper beam 10, the bins 37
R and 37L are caulked to both ends of the tray drive base 36, respectively.

Further, a laser pickup 60 for reading signals from the disk, a traverse guide 61 for the laser pickup 60 to move in a U-shape and run on the lower and upper surfaces of the laser disk, and the horizontal guide rollers of the tray 2 in FIG. 11. 35, the left and right direction is composed of an idle roller 34 and a horizontal drive binion gear 32.

The mutual relationship and operation of each of the above elements will be explained below.

In Figure 10, the laser disc 1 is placed on the tray 2.
With the laser disc 1 placed thereon, the tray 2 is moved horizontally in the direction of arrow C until the center hole of the laser disc 1 is positioned directly above the turntable 4. This horizontal movement is caused by the rotation of the tray drive motor 30 in FIG.
is transmitted to the pinion gear 32 via the pinion gear 32.
This is done by engaging a rack portion integrally formed on the lower surface of the tray 2.

Next, in FIG. 10, the motor 50 rotates and the belt 3
Gears 51 and 52 rotate through 1V.

The gears 52 are connected by a shaft 53 and act as a pair to synchronously drive the grooved cams 42R and 42L in the direction of the arrow. At this time, the two pairs of bins 37R caulked to the tray base 36,
37L slides within the cam grooves 45R, 45L, and the tray base 36 descends. At the same time, the two pairs of pins 39R and 39L crimped to the clamper beam -0 slide within the cam groove 44, and the two clamper beams 10 descend.

By lowering the tray 2 and clamper beam 10)
Place the laser disc 1 on the turntable 4,
Next, use Crano <12 to center and fix it on Turnchy Pull 4.

The paths of the cam grooves 44R, 44L of the grooved cams 42R, 42L correspond to the A-side lamp states 44, A, and 8 of the laser disc.
This is the position corresponding to the surface clap state 44B. The positions of the grooved cams 42R and 42L are controlled while being detected by a second sensor 46.

12 and 13 A and B show a state in which the clamper 12 centers and fixes the laser disc 1 on the turntable 4 by lowering the clamper beam 10.
It is.

As shown in Fig. 12, the structure of a normal laser disc (hereinafter simply referred to as a laser disc) consists of an A side IA and a 3 side A side IA.
The surfaces 1f3 are bonded together, and the central hole for determining the center of rotation for reproduction is eccentric between the A surface IA and the B surface IB. Therefore, in order to perform ideal playback, it is necessary to
When reproducing A, it is necessary to center the holes on the A side IA with the taper ring 7A, and when reproducing B side IB, it is necessary to center the holes on the B side IB with the cone 7B.

FIG. 13A shows a state in which the A side of the laser disc 1 is centered and fixed by a conventional disc clamp device.
Figure B shows the eight-plane centering fixed state.

In FIGS. 13A and 13B, a turntable 4 fixed to the shaft 3S of the motor 3 has a rubber friction material adhered to its upper end surface for contacting the laser disk 1 and transmitting rotation. A tapered ring A7 that performs A-plane centering of the laser disc 1 is urged upward by a compression spring 6.

The tapered ring B20 for eight-sided centering is urged downward by a compression spring 19. Also, a clamp ring 22 for press-contacting the laser disc 1 to the turntable 4, a compression spring 21 that biases the clamp ring 22, a press ring 18 that presses the upper ends of the compression springs 19 and 22, and a A holder 11 is provided for lifting the clamper 12 by raising the clamper beam 10 using a thrust bearing 13 provided on the r-plane of the clamper beam located at the convex portion.

In the disc clamp device configured as above, the operation of centering and fixing the A side and B side of the laser disc will be explained below.

Immediately before the 131' WA state, laser disc 1 is A
The hole in the center of the surface IA is centered by fitting into the tapered portion 7a of the tapered ring A7 which is urged upward by the compression spring 6. In the state shown in FIG. 13A, the clamper beam 10 presses the press ring 18 by the thrust bearing 13 on the lower surface, this force is transmitted to the clamp ring 22 via the compression spring 21, and the laser disc 1 is pressed against the turntable 4. A state corresponding to A-side playback is obtained. In this A-side reproduction state, the bins 39R and 39L caulked to the clamper beam 10 in FIG. 10 are located at 44A in the path of the cam grooves 44R and 44L.

To support side B playback, use bin 39R139 in Figure 10.
L is located at 44B in the path of the cam grooves 44R and 44L, and the clamper beam 10 pushes down the press ring 18 to the state shown in FIG. 13B. Therefore, as a result of pushing down the tapered ring B20 I7 via the compression spring 19, the tapered ring A7 is pushed down, and instead, the B surface of the laser disc 1 is centered with the tapered portion 20b of the tapered ring B20.

Problems to be Solved by the Invention However, with the above configuration, the clamper must be constantly pressed by the clamper beam during laser disc playback. Therefore, if external vibrations or shocks are applied to the clamper beam, the vibrations or shocks will be transmitted to the laser disc through the clamper, interfering with ideal playback and causing noise. In addition, during regeneration, a load is applied to the thrust bearing of the clamper beam and the thrust bearing of the motor, and especially during regeneration of the B side, the load increases because the two springs are compressed, which causes the problem that the life of the thrust bearing is shortened. Ta.

The present invention takes the above-mentioned problems into consideration and provides a disk clamping device for centering and fixing a laser disk on a turntable in a state where the clamper and the clamper beam are not in contact with each other during playback.

Means for Solving the Problems In order to solve the problems, the disc clamping device of the present invention centers and fixes the laser disc on the turntable using the main magnet of the clamper, and when playing the B side, Centering is performed by forcibly pushing down the taper ring for 8-sided centering with the clamper beam, but this state is immediately maintained using a sub-magnet separate from the main magnet, and the clamper beam and clamper are separated, allowing for non-contact. 17 so as to obtain the reproduction state of side A and side B in the state.

Operation According to the above-described structure of the present invention, the clamper beam and the clamper are kept out of contact during reproduction of a laser disc, so that even if external vibrations or shocks are applied to the clamper beam, they are blocked. Also, no load is applied to the thrust bearing. As a result, there will be a significant improvement in playback reliability or lifespan compared to the conventional example.Embodiment A disc clamping device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 9 shows the external drive mechanism of the disk clamp device in the first embodiment of the present invention, and FIGS.
The figure shows an internal cross section of the disc clamping device.

The basic configuration of FIG. 9 is the same as the conventional example shown in FIG. 10, but the cam grooves 42R and 42L are
In the path of 4R and 44L, 44B corresponds to the B-side playback state.
The difference is that 44C is provided following .

As shown in FIGS. 1 to 6, the device includes a turntable 6
4. Taper ring A67 for centering the A side
, an attraction link 65 made of a magnetic material, and this attraction ring 65 also serves as a stopper for the tapered ring A67 that is urged upward by the spring 6. Furthermore, it is composed of a press ring 80 integrally molded with the yoke 81 of the main magnet 82, a compression spring 83, a clamping ring 84° that presses the laser disc against the turntable, a sub magnet 85, and a yoke 86, and the yoke 86 is centered on the B side. It is bonded to the taper ring B87 for The tapered portion 87b of the tapered ring B87 is not completely continuous all around, but is divided into 2.3 parts, and vertically passes through the slit formed in the press ring 80. Further, the tapered rings B87 are guided and slidable in the center hole of the press ring 80, but are urged away from each other by a compression spring 88.
It is caught and stopped by the claw 80C of the press ring 80. Furthermore, the center hole 87H of the tapered ring B87 is dimensioned so as to be slidably fitted onto the shaft 3S of the motor 3.

Regarding the disk clamping device configured as described above, the relationship between each component and its operation will be explained below using FIG. 9 and FIGS. 1 to 6.

FIG. 9 shows the external drive mechanism of the disk clamp device,
This represents a state in which the clamper beam 10 is raised, that is, the clamper 72 and the turntable 64 are separated, and the tray 2 on which the laser disc 1 is placed can be moved horizontally.

FIG. 1 shows an internal cross section of the disk clamp device in the state shown in FIG. 9.

FIG. 2 shows a state corresponding to reproduction of side A of a normal laser disc. The clamper 72 and the clamper beam 10 are not in contact. Laser disc 1 has taper ring A67
The A side is centered by the taper portion 67a, and is pressed against the turntable 64 by the crumpling ring 84.

The pressure contact force is generated by the main magnet 82 fixed to the yoke 81.
This is generated by the suction force between the suction ring 65 and the suction ring 65. In this state, the press ring 80 and the clamp ring 84 are in close contact with each other in the vertical direction and have become rigid bodies, so the magnitude of the pressing force is determined only by the suction force of the main magnet 82 and the suction ring 65, and does not depend on the compression spring 83. I haven't.

On the other hand, FIG. 3 shows a state corresponding to reproduction of a laser disc (referred to as a laser disc single) 101 consisting of side A only. Only side A of Laser Disc Single 101 is played (1). Further, the centering state of the laser disc single 101 is similar to that of a normal laser disc, but the state in which it is pressed against the turntable 64 is different. That is, since the laser disc single 101 has only half the thickness of a normal laser disc, the main magnet 82 and the suction ring 65 come into close contact with each other first before the press ring 80 and the crumbling ring 84 come into close contact with each other. Therefore laser disc single 1
01 to the turntable 64 is applied by the compression spring 83.
Occurs due to

FIG. 4 shows a state in which the clamper beam 0 has been lowered to the lowest position to force centering of the B side of the laser disc 1 in order to reproduce the B side. In other words, the taper ring B87 is fitted and guided by the shaft 3S of the motor 3, pushes down the taper ring A67, and centers the B surface of the laser disc 1 by the tapered portion 87b of the taper ring B87. This state is the 1st O
In the figure, this occurs due to the action of the lowest portion 44C of the cam groove 44. Further, in this state, the clamper beam 10 and the clamper 72 are in contact only at the central convex portion of the tapered ring B87, so there is no problem even while the turntable 64 and the laser disc 1 are rotating.

FIG. 5 shows a state corresponding to reproduction of the B side of the laser disc 1. In other words, from the state shown in Fig. 4, the clamper beam 1
0 has risen slightly and the clamper 72 is not in contact with the clamper beam. In this state, the sub-magnet 85 bonded to the taper ring B87 is sufficiently close to the yoke 81 of the main magnet 82, and the suction force of the sub-magnet 85 exceeds the repulsive force of the compression spring 88, so that the laser disc 1 The 8-plane centering state is self-maintained.

Incidentally, although there is considerable variation in the actual thickness of the laser disc 1 in FIG. 2, since the press ring 80 and the clamp ring 84 are constructed so as to form a tight and rigid body in the clamped state, the taper ring B87 The distance between the tapered portion 87b and the B surface of the laser disc 1 is
It is constant without being affected by variations in the thickness of the laser disk 1. Therefore, the variation in the movement stroke of the taper ring B87 when centering the B surface is reduced, and as a result, the sub magnet 85 and the yoke 8
There is an advantage that the variation in distance in the self-holding state 1 is also reduced, and the variation in self-holding force is also reduced.

To switch the playback state from side B to side A of the laser disc 1, raise the clamper beam 10 to the position shown in FIG.
After removing the disc, it is sufficient to return to the A-side playback compatible state as shown in FIG.

As in this embodiment described above, the laser disk is centered and fixed on the turntable by the suction force of the main magnet that constitutes the clamper, and the tapered ring B for surface centering is slidable relative to the main magnet.
If the taper ring B is equipped with a sub-magnet and a compression spring for self-holding, and the position of the taper ring B is changed and held by the force of the clamper beam, the clamper and the clamper can be Reproduction can be performed with the beams spatially separated.

A second embodiment of the present invention will be described below with reference to the drawings.

FIG. 7 is a sectional view of a disc clamping device in an 8-side playback state showing a second embodiment of the present invention. The difference in the configuration from the one shown in FIGS. 1 to 6 is that the press ring 8
0 and the tapered ring B87, in addition to the compression spring 88, another compression spring 89 is provided.

The operation of the disk clamp device configured as described above will be explained below.

FIG. 7 shows a state corresponding to the reproduction of the B side of the laser disc 1, in which the clamper 72 is stabilized on the turntable 64 by the attraction force between the main magnet 82 and the suction ring 65. However, in this state, the suction force of the sub magnet 85 acts together with the compression spring 83 to pull the main magnet 82 away from the turntable 64. The attractive force of the sub magnet 85 is Fss, the repulsive force of the compression spring 88 is fss, and the repulsive force of the compression spring 83 is f
83, if there is no additional compression spring, fss+
fas fas acts as a force that pulls the main magnet 82 apart.

The magnitude of the attraction force F85 of the sub-magnet varies depending on the distance S between the sub-magnet 85 and the yoke 81, as shown in FIG. Since there are variations in dimensions, it is necessary to consider the balance within a certain width range as shown in the shaded area in FIG. If the distance S becomes small, the value of (F ss - f ss) increases suddenly, and there is a possibility that the suction force of the main magnet 85 becomes insufficient and the main magnet 85 becomes detached from the turntable 64 .

As a countermeasure for this, another compression spring 89 is added to give a repulsive force f89, and Fss
If the value of (fss+fa9) is configured to be approximately constant, the force that tries to separate the main magnet 82 will be approximately constant in the practical range, and a stable clamping state can be realized.

Effects of the Invention As is clear from the description of the embodiments above, the present invention utilizes the suction force of the main magnet, which is a component of the clamper, when centering and fixing the laser disc on the turntable. With the laser disc in close contact with the rigid body, the A side of the laser disc is centered and fixed to the turntable, and a taper ring for surface centering that can be moved relative to the main magnet is added, and this taper ring is attached to both ends of the stroke. 1. When switching the playback surface of the disc, the self-holding position of the ten-bar ring is switched by external force, and the external force is released during playback. By operating the laser disc in this manner, it is possible to realize reproduction of both sides of the laser disc without contacting the external force operating section. Also 1
By adding a spring that acts only near the end of the stroke of the three-plane centering taper ring, it is possible to stabilize the holding force of the main magnet to the turntable in the eight-plane playback mode.

[Brief explanation of drawings]

1 to 6 are cross-sectional views of a disk clamping device according to a first embodiment of the present invention. FIG. 7 is a sectional view of a disk clamp device according to a second embodiment of the present invention, and FIG. 8 is a diagram for supplementary explanation of FIG. 7. FIG. 9 is a perspective view showing the external drive mechanism of the disk clamp device according to the first embodiment of the present invention. FIG. 10 is a perspective view showing an external drive mechanism of a conventional disk clamp mechanism, and FIG. 11 is a sectional view thereof. FIG. 12 is a sectional view showing the principle of centering a laser disk, and FIG. 13A is a cross-sectional view showing the principle of centering a laser disk. B is a sectional view showing a conventional disk clamp device. 1...Laser disc, lA...Side A of the laser disc, IB...Side 8 of the laser disc, 64...Turntable, 67.
...Chiba 2.G A (tapered member), 6
7a... Taper part, 80... Press ring, 82... Main magnet, 83...
...Compression spring, 84... Crumbly: zY(
disc pressing member), 85... sub magnet, 87... taper ring B (tapered portion 4.4
), 87 b... Taper part, 88...
・Compression spring, 89... Spring.

Claims (3)

[Claims] (1) A turntable for mounting and rotating a disk, a first magnet for fixing the disk to the turntable by suction, and a turntable that is movable relative to the first magnet and biased by a spring force. a disk pressing member, a first tapered member for centering one side of the disk, a second tapered member for centering the other side of the disk, and a first tapered member for centering the other side of the disk; a spring and a second magnet for self-holding the second tapered member in two relative positions; and means for applying an external force to the clamper for switching the clamp mode between the one surface and the other surface of the disk. Equipped with a disc clamp device. (2) By bringing the first magnet into contact with the disc pressing member through the member that supports the first magnet, the suction force of the first magnet can be directly applied to the disc pressing force without using a spring force. Claim 1 constituted so that
Disc clamping device as described. (3) providing a spring that acts near the end of the suction stroke by the second magnet of the second tapered member;
2. The disk clamp device according to claim 1, wherein the self-holding force of the second tapered member obtained by attraction of the second magnet is smoothed.