JP2858337B2 - Disc clamp device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-disc player (hereinafter, a disc player) which also plays a laser disc player or a compact disc (hereinafter, referred to as a CD) and a compact disc with video (hereinafter, a CDV). )
The present invention 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 reproduction type disc players have become widespread, and disk clamp devices developed for double-sided automatic reproduction have been used.

Hereinafter, a conventionally used disk clamp device will be described.

FIG. 10 and FIG. 11 show a main drive mechanism of a disk player having a conventional disk clamp device. As shown in FIGS. 10 and 11, the apparatus includes a laser disk 1, a tray 2 for transporting the loaded disk, a tray drive motor 30, and a tray base 36. Motor 3 for reproduction,
It comprises a turntable 4 fixed to the shaft 3S of the motor 3, a disk clamper 12, and a clamper beam 10 for raising and lowering the disk clamper 12.

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 cams 42R, the horizontal guides for the groove cams 42R, 42L, and the pins 39R, 39L, 37R , 37L vertical guides 41R, 41L, the pins 39R, 39L are both ends of the clamper beam 10, the pins 3
7R and 37L are caulked at both ends of the tray drive base 36, respectively.

Further, a laser pickup 60 for reading a signal of the disk, and a draft guide 61 for moving the laser pickup 60 in a U-shape to travel on the lower surface and the upper surface of the laser disk. The tray 2 shown in FIG. 11 includes a horizontal guide roller 35, a horizontal guide roller 34, and a pinion gear 32 for horizontal drive.

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

In FIG. 10, the laser disk 1 is placed on the tray 2.
Is placed, the tray 2 moves horizontally in the direction of arrow C until the hole at the center of the laser disk 1 is located directly above the turntable 4. In this horizontal movement, the rotation of the tray drive motor 30 in FIG. 11 is transmitted to the pinion gear 32 via the belt 31H, and the pinion gear 32
By engaging with a rack part integrally formed on the lower surface of the.

Next, the motor 50 rotates in FIG.
The gears 51 and 52 are rotated via. The gears 52 are coupled by a shaft 53 to form a pair, and synchronously drive the groove cams 42R and 42L in the direction of arrow D. At this time, 2 crimped on the tray base 36
The pair of pins 37R, 37L slide in the cam grooves 45R, 45L, and the tray base 36 descends. At the same time, the two pairs of pins 39R and 39L caulked by the clamper beam 10 slide in the cam groove 44, and the clamper beam 10 descends.

The laser disk 1 is placed on the turntable 4 by lowering the tray 2 and the clamper beam 10, and then the laser disk 1 is centered and fixed to the turntable 4 by the clamper 12.

The paths of the cam grooves 44R and 44L of the groove cams 42R and 42L are represented by a laser disk A-side clamp state 44A and a B-side clamp state 44B.
Is the position corresponding to The positions of the groove cams 42R and 42L are controlled while being detected by the limit switch 46.

FIGS. 12 and 13A and 13B show a state in which the clamper 12 has the laser disk 1 centered and fixed to the turntable 4 by the lowering of the clamper beam 10. FIG.

As shown in FIG. 12, the structure of a normal laser disc (hereinafter simply referred to as a laser disc) is composed of A side 1A and B side.
The center hole for determining the rotation center of reproduction has an eccentricity between the A surface 1A and the B surface 1B. Therefore, in order to perform ideal reproduction, when reproducing the A surface 1A, the hole of the A surface 1A is centered by the taper ring 7A, and when reproducing the B surface 1B, the hole of the B surface 1B is formed by the cone 7B. Need to be centered.

FIG. 13A shows a centering fixed state of the surface A of the laser disk 1 by a conventional disk clamping device, and FIG. 13B shows a centering fixed state of the surface B.

13A and 13B, the turntable 4 fixed to the shaft 3S of the motor 3 has a rubber-based friction material for contacting the laser disk 1 and transmitting the rotation adhered to the upper end surface. The taper ring A7 for centering the A surface of the laser disk 1 is urged upward by a compression spring 6. The taper ring B20 for centering the B surface is urged downward by the compression spring 19. A clamp ring 22 for pressing the laser disc 1 against the turntable 4, and a compression spring for urging the clamp ring 22.
21, a press ring for pressing the upper ends of the compression springs 19 and 22
18, a thrust bearing 13 provided on the lower surface of the clamper beam located at the center convex portion of the press ring 18, and a holder 11 for lifting the clamper 12 by raising the clamper beam 10.

Hereinafter, the operation of centering and fixing the laser disk A surface A and the surface B in the disk clamp device configured as described above will be described.

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

In order to cope with the B-side reproduction, the pins 39R and 39L in FIG. 10 are 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 taper ring B20 via the compression spring 19, the taper ring A7 is pushed down, and instead, the B surface of the laser disk 1 is centered by the taper portion 20b of the taper ring B20.

However, in the above configuration, the clamper must be constantly pressed by the clamper beam during reproduction of the laser disk. Therefore, when vibration or shock is applied to the clamper beam from the outside, the vibration or shock is transmitted to the laser disk through the clamper, which hinders ideal reproduction and also causes noise. In addition, a load is constantly applied to the thrust bearing of the clamper beam and the thrust bearing of the motor during the reproduction, and the load is increased due to the compression of the two springs particularly during the reproduction of the B-plane, so that the life of the thrust bearing is shortened. Was.

The present invention has been made in view of the above problems, and provides a disk clamp device for realizing centering and fixing of a laser disk to a turntable in a state in which a clamper and a clamper beam are not in contact during reproduction.

Means for Solving the Problems In order to solve the above problems, a disk clamp device of the present invention is arranged such that a laser disk is centered and fixed on a turntable by a main magnet of a clamper. The centering is performed by forcibly pressing down the surface centering taper ring with the clamper beam, but this state is immediately held by using a sub-magnet separate from the main magnet, and the clamper beam and the clamper are separated to form a non-contact state. To obtain the reproduction state of the A side and the B side.

According to the present invention, since the clamper beam and the clamper are kept out of contact with each other during the reproduction of the laser disk by the above-described configuration, even if the clamper beam is externally subjected to vibration or impact, it is shut off. Also, no load is applied to the thrust bearing. As a result, a significant improvement in the reliability of reproduction or the life point is obtained as compared with the conventional example.

Embodiment A disk clamp device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 9 shows an external drive mechanism of the disk clamp device according to the first embodiment of the present invention, and FIGS. 1 to 6 show internal sections of the disk clamp device.

The basic configuration of FIG. 9 is the same as that of the conventional example shown in FIG. 10, except that in the path of the cam grooves 44R and 44L formed in the groove cams 42R and 42L, Subsequently, the point that 44C is provided is different.

As shown in FIGS. 1 to 6, the device is a turntable.
64, Taper ring A67 for centering A side,
It consists of a suction link 65 made of a magnetic material, and this suction ring 65 is a tapered ring urged upward by the spring 6.
Also serves as A67 stopper. A press ring 8 in which the main magnet 82 is formed integrally with the yoke 81
0, compression spring 83, clamp ring 84 for pressing the laser disc against the turntable. Sub magnet 85, yoke 8
The yoke 86 is bonded to a taper ring B87 for centering the B surface. Taper ring B87
The tapered portion 87b is not completely continuous over the entire circumference, but is divided into a few places, and penetrates vertically through a slit formed in the press ring 80. Also tapering
The B87 is guided by the center hole of the press ring 80 and is slidable, but is urged away from each other by a compression spring 88, and is stopped by being caught by the claw C of the press ring 80. Further, the center hole 87H of the tapered ring B87 is dimensioned so as to be slidably fitted to the shaft 3S of the motor 3.

Regarding the disk clamp device configured as described above, the relationship between the components and the operation thereof will be described below with reference to FIG. 9 and FIGS. 1 to 6.

FIG. 9 shows an external driving mechanism of the disk clamp device, 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 disk 1 is mounted can move horizontally. Indicates the state.

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

FIG. 2 shows a state corresponding to A-side reproduction of a normal laser disk. The clamper 72 and the clamper beam 10 are not in contact. The laser disk 1 is centered on the surface A by the tapered portion 67a of the tapered ring A67, and is pressed against the turntable 64 by the clamp ring 84.

The pressing force is generated by the attraction force between the main magnet 82 fixed to the yoke 81 and the attraction ring 65. In this state, the press ring 80 and the clamp ring 84 are tightly attached to each other in the vertical direction and are rigid, so the magnitude of the pressing force is determined only by the attraction force of the main magnet 82 and the attraction ring 65, and depends on the compression spring 83. I haven't.

On the other hand, FIG. 3 shows a state corresponding to the reproduction of a laser disk (called a laser disk single) 101 consisting only of the A side. Reproduction of the laser disc single 101 is performed only on the A side. The centering state of the laser disk single 101 is the same as that of a normal laser disk, but the state of being pressed against the turntable 64 is different. That is, since the thickness of the laser disk single 101 is only half the thickness of a normal laser disk, the main magnet 82 and the attraction ring 65 come into close contact with each other before the press ring 80 and the clamp ring 84 come into close contact with each other. Therefore turntable 64 for laser disc single 101
The pressure contact force is generated by the compression spring 83.

FIG. 4 shows a state in which the clamper beam 10 is lowered to the lowest position in order to cope with the reproduction of the B surface of the laser disk 1 and the centering of the B surface is forcibly performed. That is, in a state where the tapered ring B87 is fitted and guided on the shaft 3S of the motor 3, the tapered ring A67 is pressed down and the tapered portion 87b of the tapered ring B87 causes the tape B 87 of the laser disk 1 to move.
Center the face. This state is caused by the action of the lowest portion 44C of the cam groove 44 in FIG. Further, in this state, the clamper beam 10 and the clamper 72 are in contact with each other only at the central convex portion of the tapered ring B87, so that even during the rotation of the turntable 64 and the laser disk 1, it may be acceptable.

FIG. 5 shows a state corresponding to the B-side reproduction of the laser disk 1. That is, the clamper beam is shifted from the state shown in FIG.
10, the clamper 72 is slightly in contact with the clamper beam. In this state, the sub magnet 85 bonded to the tapered ring B87 is sufficiently close to the yoke 81 of the main magnet 82, and the attraction force of the sub magnet 85 causes the compression spring
Laser Disc 1
B centering state is held by itself.

In FIG. 2, the actual thickness of the laser disk 1 varies considerably. However, since the press ring 80 and the clamp ring 84 are configured to be in tight contact with each other in a clamped state, the taper ring B87 The distance between the tapered portion 87b and the surface B of the laser disk 1 is constant without being affected by the variation in the thickness of the laser disk 1. Therefore, the variation in the movement stroke of the taper ring B87 when centering the surface B is reduced, and as a result, the variation in the distance between the sub-magnet 85 and the yoke 81 in the self-holding state is reduced, and the variation in the self-holding force is also reduced. There are advantages.

In order to switch the reproducing state from the side B to the side A of the laser disk 1, the clamper beam 10 is raised to the position shown in FIG. 6, the laser disk 1 is detached from the turntable 64, and then the operation returns to FIG. The state shown in FIG.

As in the present embodiment described above, the centering and fixing of the laser disk to the turntable are performed by the attraction force of the main magnet constituting the clamper, and the B-plane centering taper ring B slidable with respect to the main magnet is provided. A self-holding sub-magnet and a compression spring are disposed on the taper ring B to form a clamper. By switching the position of the taper ring B by the force of the clamper beam and self-holding, the clamper and the clamper beam are spatially separated. Reproduction can be performed in a state in which they are apart from each other.

Hereinafter, a second embodiment of the present invention will be described with reference to the drawings.

FIG. 7 is a sectional view of a disk clamp device in a B-side reproducing state according to a second embodiment of the present invention. The difference between the structure shown in FIGS.
Another point is that another compression spring 89 is provided between 80 and the tapering B87 in addition to the compression spring 88.

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

FIG. 7 shows a state corresponding to the B-side reproduction of the laser disk 1, and the clamper 72 is stabilized on the turntable 64 by the attraction between the main magnet 82 and the attraction ring 65. However, in this state, the attraction force of the sub magnet 85 works together with the compression spring 83 to separate the main magnet 82 from the turntable 64. The attraction force of the sub magnet 85 is F ₈₅ and the repulsion force of the compression spring 88 is
f _88, if f ₈₃ the repulsive force of the compression spring 83, if there is additional portion of the compression spring, f ₈₃ + f ₈₅ -f ₈₈ main magnet 82
Act as a force to pull apart.

The magnitude of the suction force F ₈₅ of the sub magnets, as shown in FIG. 8, varies with the distance S of the sub magnet 85 and the yoke 81, practically dimensional variations of the center hole of the laser disk 1, tapering B87 Therefore, it is necessary to consider the balance in a range having a certain width as shown by the hatched area in FIG. If the distance S decreases, the value of (F ₈₅ −f ₈₈ ) increases abruptly, so that there is a possibility that the attractive force of the main magnet 85 becomes insufficient and the main magnet 85 comes off the turntable 64.

To provide a repulsive force f ₈₉ by adding another compression spring 89 as a countermeasure, moreover F ₈₅ - (f
If the value of ( ₈₈ + _f89 ) is made substantially constant, the force for separating the main magnet 82 becomes almost constant between the practical regions, and a stable clamping state can be realized.

Effect of the Invention As is clear from the above description of the embodiment, in fixing the laser disk to the turntable, the present invention utilizes the attraction force of the main magnet, which is a constituent element of the clamper, to form a support for the main magnet. In the state of being in close contact with the rigid body, centering of the A side of the laser disk and fixing to the turntable are performed, and a taper ring for the B side centering which can be relatively moved is added to the main magnet. Sub-magnet and compression spring are arranged so as to be self-holding at both ends. When switching the playback surface of the laser disk, the self-holding position of the taper ring is switched by external force, and the external force is released during playback. By doing so, the laser disc in a state of non-contact with the external force operation unit Reproduction on both sides can be realized. Also B
By adding a spring that acts only near the end of the stroke of the surface centering taper ring, the holding force of the main magnet on the turntable in the B-side reproduction mode can be stabilized.

[Brief description of the drawings]

1 to 6 are sectional views of a disk clamp 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. FIG. 9 is a perspective view showing an 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,
FIG. 11 is a sectional view thereof. FIG. 12 is a cross-sectional view showing the principle of centering a laser disk, and FIGS. 13A and 13B are cross-sectional views showing a conventional disk clamp device. 1 ... Laser disc, 1A ... Laser disc A
Surface, 1B: Laser disk B surface, 64: Turntable, 67: Tapering A (tapered member), 67a
… Taper portion, 80… press ring, 82… main magnet, 83… compression spring, 84… clamp ring (disk pressing member), 85… sub magnet, 87… taper ring B (tapered member) ), 87b …… Tapered section, 88 ……
Compression spring, 89… spring.

Claims (3)

(57) [Claims] 1. A turntable for mounting and rotating a disc, a first magnet for fixing the disc to the turntable by suction, and a movable relative to the first magnet and biased by a spring force. A first tapered member for centering one surface of the disk, a second tapered member for centering the other surface of the disk, and the first magnet. A spring and a second magnet for self-holding the second tapered member at two relative positions, and means for applying an external force to the clamper for switching a clamp mode between the one surface and the other surface of the disk. And a disk clamp device comprising: 2. The method according to claim 1, wherein the first magnet is brought into contact with the disk pressing member via a member supporting the first magnet, so that the attraction force of the first magnet directly pushes the disk without the intervention of a spring force. 2. The disc clamp device according to claim 1, wherein the disc clamp device is configured to generate pressure. 3. A spring acting near the end of a suction stroke of the second tapered member by the second magnet is provided to smooth the self-holding force of the second tapered member obtained by the suction of the second magnet. The disk clamp device according to claim 1, wherein the disk clamp device is formed.