JP2000048474A - Turntable device for disk player - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a turntable device capable of performing a disk rotating operation in a stable state. SOLUTION: A plurality of ball bearings 12 are disposed in a groove 11 movably along the groove 11 formed in a rotation control member 10 attached so as to be integrally rotated with a turntable 4 for loading a disk D, and a coil spring 13 is disposed between the ball bearings 12. Thus, the rotary- driving operation of the disk D is performed in a stable state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turntable device on which a disk is placed and which rotates the disk.

[0002]

2. Description of the Related Art Disk players which read signals recorded on a disk using an optical pickup have become widespread. Such a disk player has a turntable on which the disk is placed. . The disc placed on the turntable is fixedly held on the turntable so as to rotate together with the turntable by means called a clamp,
A device utilizing the attraction force of a magnet has been developed as the clamping means. In the technique of performing the clamping operation of the disk by using the attraction force of the magnet, a magnetic material that is attracted by the magnet is provided on the turntable side. Such a turntable is disclosed in Japanese Utility Model Laid-Open No. 5-21354. Something was done.

[0003] As a disk player, a CD player is generally used, but recently, a CD called a CD-ROM for recording a data signal used by a computer, not a sound signal of music or the like, is reproduced. -Disk players called ROM players are widespread.

[0004]

The CD-ROM player, unlike the CD player that reproduces an audio signal, requires a high-speed reading operation of a signal. 2. Description of the Related Art Disk players configured to perform a signal reading operation by rotating a disk at a high linear velocity such as 6 times, 8 times, and 10 times have been commercialized.

In order to rotationally drive the disk so that the linear velocity becomes constant at a high speed, an expensive spindle motor with good characteristics and a high-precision drive control circuit are required. Disc players have been commercialized that are configured to control the angular velocity not at a constant linear velocity but at a constant angular velocity.

[0006] Among disks used in such a disk player, there is a disk called an eccentric disk whose center of gravity is shifted from the center. When such a disk is rotated at high speed, abnormal vibration occurs. However, there is a problem that abnormal noise is generated. As a method for solving such a problem, a turntable device using a ball bearing has been developed. However, when the rotation speed is low, the ball bearings collide with each other and generate noise.

An object of the present invention is to provide a turntable device for a disk player which solves such a problem.

[0008]

A turntable device according to the present invention has a mounting portion on which a disk is mounted, a center ring portion inserted into a center hole formed in the disk, and a spindle. A turntable fixed to the rotating shaft of the motor, a rotation control member mounted to rotate integrally with the turntable and having a ring-shaped groove formed therein, and formed on the rotation control member. The ball bearing includes a plurality of ball bearings movably disposed along the groove and elastic means disposed between the ball bearings.

[0009]

FIG. 1 is a side sectional view of an essential part showing an embodiment of a turntable device of the present invention, and FIGS. 2, 3 and 4 are plan views for explaining the operation of the turntable device of the present invention. It is.

In FIG. 1, reference numeral 1 denotes a spindle motor which is rotated when supplied with power when reproducing a signal recorded on a disk D. The spindle motor 1 has a rotating shaft 2 and a screw (shown in FIG. )). Reference numeral 4 denotes a turntable in which a mounting portion 5 on which the disk D is mounted and a press-fitting hole 6 for press-fitting the rotary shaft 2 of the spindle motor 1 are formed. The turntable 4 is inserted into a center hole formed in the disk D. A centering portion 7 is formed.

A tapered portion 7A is formed on the upper side surface of the center ring portion 7, and a positioning hole 8 is formed in the center of the upper surface of the center ring portion 7, and the opening is formed in a mortar shape as shown in the figure. Is formed. 9
Is a ring-shaped magnetic body fixed to the center ring portion 7, and is fixed to a mounting portion provided on the center ring portion 7 with an adhesive or the like.

Reference numeral 10 denotes a rotation control member in which a ring-shaped groove 11 is formed, and is attached so as to rotate integrally with the turntable 4. Reference numeral 12 denotes a ball bearing inserted and arranged inside the groove 11 provided in the rotation control member 10, and a plurality of, for example, eight ball bearings are provided. Reference numeral 13 denotes a coil spring disposed between each of the ball bearings 12 disposed in the groove 11, and all the ball bearings 1 when the turntable 4 is in the rotation stop state or the low-speed rotation state.
2 is configured to be in a state of applying an elastic urging force.

In such a configuration, the rotation control member 10 is formed of a synthetic resin, and eight ball bearings 12 and 8 are provided in a groove 11 formed in the rotation control member 10.
After the coil springs 13 are inserted, the rotation control member 1
The rotation control member 10 can be attached and fixed to the turntable 4 so that the rotation control member 10 rotates integrally with the turntable 4 by bonding the rotation control member 10 to the lower surface of the turntable 4 with an adhesive.

The press-fitting hole 6 formed in the turntable 4 assembled as described above is pressed into the rotary shaft 2 of the spindle motor 1 to fix the turntable 4 to the rotary shaft 2 of the spindle motor 1. I can do it.

In the turntable device having such a configuration, when the disk D is driven to rotate by the spindle motor 1, the position of the center of rotation does not coincide with the position of the center of rotation, that is, the position of the rotating shaft 2, so that the disk D Is performed in an unbalanced state. When the rotation of the turntable 4 is stopped or the rotation speed is low, the positional relationship between the ball bearing 12 and the coil spring 13 arranged in the groove 11 formed in the rotation control member 10 is as follows. It is in the state shown in FIG. In such a state, all the ball bearings 12 are in a state of receiving the urging force of the coil spring 13, so that not only the ball bearings do not collide with each other, but also the unnecessary displacement operation of each ball bearing is performed. Nothing is done.

As the rotation speed of the turntable 4 increases, the centrifugal force acting on the ball bearing 12 gradually increases, and the ball bearing 12 moves in the rotation direction while rolling in the groove 11. And
Since the movement of the ball bearing 12 is performed against the elastic force of each coil spring 13, the coil spring 13 is compressed. FIG. 3 shows a state at the time of acceleration to a medium speed rotation state or a high speed state. In such a state, the ball bearings 12 do not collide with each other, so that no noise is generated. Also,
In such a state, one of the coil springs is in a non-compressed state, and this coil spring moves together with the ball bearing 12 to a position that improves the unbalanced state.

FIG. 4 shows a high-speed rotation state, in which the coil spring 13 is largely compressed. Also, in this case, one coil spring is in a non-compressed state.
2 together with the position for improving the unbalanced state. As described above, the ball bearing 12 and the coil spring 13 are at a position where the unbalanced state is improved as the rotation speed of the turntable 4 increases.
Moves to a position corresponding to the degree of imbalance.

As a result of the movement of the ball bearing 12 to a position where the unbalanced state is improved, the rotational driving operation of the disk D by the spindle motor 1 is performed in a balanced state. Therefore, disk D
Even when the disk is an eccentric disk, the rotational drive operation of the disk D can be performed in a well-balanced manner, so that occurrence of abnormal vibration can be suppressed.

As described above, the rotation drive operation of the disk D by the turntable device of the present invention is performed, but when the rotation stop operation of the disk D is performed, the deceleration operation and the stop operation of the spindle motor 1 are performed. For,
The turntable 4 is rapidly moved from the high-speed rotation state to the stop state. When the rotation speed of the turntable 4 decreases, the centrifugal force acting on the ball bearing 12 gradually decreases. When the force becomes smaller than the elastic force of the coil spring 13, the ball bearing 12 is moved by the elastic force of the coil spring 13. It moves while rolling in the groove 11 and moves to the position shown in FIG.

In this embodiment, the coil spring is used as the elastic means disposed between the ball bearings. However, an elastic member such as a sponge may be used.

[0021]

According to the turntable device of the present invention, a plurality of balls are provided in a ring-shaped groove formed in a rotation control member mounted to rotate integrally with a turntable on which a disk is mounted. Since the bearing and the elastic means are arranged, even when the position of the center of gravity and the rotation axis do not coincide with each other as in the case of the eccentric disk, the ball bearing and the elastic means move to a position where the unbalanced state is improved, and the balance is improved. In order to achieve the balanced state, the disk can be driven to rotate in a balanced state. Therefore, according to the present invention, it is possible to suppress abnormal vibration that has occurred when the eccentric disk is rotated at high speed, so that it is possible to prevent the generation of abnormal noise and to read signals from the disk. Can be improved.

Further, according to the present invention, since the elastic means is disposed between the ball bearings, the ball bearings do not collide with each other, and the generation of abnormal noise due to the collision between the ball bearings can be prevented.

According to the present invention, when the turntable is in the rotation stop state, all the ball bearings are in a state of receiving the urging force of the elastic means, so that the ball bearings are moved unnecessarily. In addition to this, the ball bearing does not move to the lower end when the disk is driven to rotate in the vertical direction instead of the horizontal direction, so that the characteristics at the start of rotation of the turntable can be improved. It has the advantage of being able to.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a main part showing one embodiment of a turntable device of the present invention.

FIG. 2 is a plan view for explaining the operation of the turntable device of the present invention.

FIG. 3 is a plan view for explaining the operation of the turntable device of the present invention.

FIG. 4 is a plan view for explaining the operation of the turntable device of the present invention.

[Explanation of symbols]

 D disk 1 spindle motor 2 rotation axis 4 turntable 10 rotation control member 11 groove 12 ball bearing 13 coil spring

Claims (4)

[Claims] A turntable formed with a mounting portion on which a disk is mounted and a center ring portion inserted into a center hole formed in the disk, and fixed to a rotating shaft of a spindle motor; A rotation control member mounted to rotate integrally with the turntable and having a ring-shaped groove formed therein; and a rotation control member disposed in the groove formed in the rotation control member so as to be movable along the groove. A turntable device for a disk player, comprising: a plurality of ball bearings; and elastic means disposed between the ball bearings. 2. The turntable device according to claim 1, wherein a coil spring is used as the elastic means. 3. The turntable device according to claim 1, wherein a sponge is used as the elastic means. 4. The turntable device according to claim 1, wherein when the turntable is in a rotation stop state, all the ball bearings are in a state of receiving the urging force of the elastic means.