JP2001344888A - Turntable device of disk player - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the generation of vibration of a high frequency during motor driving with inexpensive constitution. SOLUTION: This device 1 is a device for rotating a disk 17 of a circular plate form and has a turntable 3, a weight 4 and a spindle motor 5. The turntable 3 is a member to be mounted with the disk 17. The weight 4 is mounted in an outer peripheral region 3a of a portion of the turntable 3. The spindle motor 5 rotationally drives the turntable 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turntable device, and more particularly to a turntable device for rotating a disk.

[0002]

2. Description of the Related Art A disc player for reproducing a disc such as a CD or an MD generally includes a turntable device for rotating the disc. The turntable device includes a turntable on which a disc is placed, and a motor for driving the turntable to rotate. The motor has a rotating shaft connected to the turntable.

[0003] In this device, the rotation shaft is rotated by driving the motor, and the turntable fixed to the rotation shaft is rotated. In this type of turntable device, when an eccentric disk with an eccentric center of gravity is mounted, when the turntable rotates, the rotation shaft is shaken, and vibration occurs, which may cause a tracking error.

To cope with such a problem, Japanese Patent Application Laid-Open
Techniques such as those disclosed in JP-A-11-39787, Utility Model Registration No. 3048548, JP-A-11-39784, and JP-A-10-275411 have already been proposed. In the device disclosed in the above publication, a member serving as a weight is movably disposed inside a turntable or a member that can be integrally rotated with the turntable, and the weight member receiving the centrifugal force is balanced in the turntable. Is moved, the occurrence of vibration when the eccentric disk is placed can be suppressed.

[0005]

By the way, in addition to the case where the vibration occurs due to the eccentric disk as described above, the case where the vibration occurs due to the turntable itself constituting the turntable device may occur. is there. That is, the center of gravity of the turntable may be shifted from the center of rotation of the turntable due to a manufacturing error. If a turntable having such a shift is used in the device, the rotation of the motor causes the rotation shaft of the motor to rotate. Vibration occurs.

In particular, when the deviation from the position of the center of gravity to the center of rotation is slight, a high frequency vibration is generated when the turntable rotates, so that there is no room for the servo following performance of the pickup (reading device). The tracking function is degraded, and a disk reading error is likely to occur. However, the apparatus disclosed in the above publication can suppress vibration when the eccentric disk is placed, but suppresses vibration when there is a manufacturing error in the turntable itself constituting the turntable device. It is not possible.

Although it is possible to suppress the vibration by suppressing the variation in the manufacturing accuracy of the turntable, the manufacturing cost of the turntable becomes extremely high. SUMMARY OF THE INVENTION It is an object of the present invention to suppress the occurrence of high-frequency vibration during motor driving with an inexpensive configuration.

[0008]

According to a first aspect of the present invention, there is provided a turntable device for rotating a disk-shaped disk, comprising a turntable, a weight member, and a motor. I have. The turntable is a member on which a disc is placed. The weight member is mounted on a part of an outer peripheral area of the turntable. The motor rotates the turntable.

In this apparatus, when a disk is placed on a turntable and a motor is driven, the turntable rotates and the disk rotates. At this time, since the weight member is mounted on the turntable and the center of gravity is eccentric, the rotation shaft of the motor rotates with a shake. As a result, low-frequency vibration is generated, and high-frequency vibration is suppressed.

Generally, the servo following characteristic of the pickup when low-frequency vibration occurs has more margin than when high-frequency vibration occurs. For this reason, a disk reading error can be suppressed. The turntable device according to claim 2 is the device according to claim 1,
The weight member has a male screw portion formed therein, and the turntable has a female screw portion to which the weight member is mounted.

In this device, since the weight member is mounted by screwing the male screw portion into the female screw portion, the attachment / detachment operation with respect to the turntable becomes easy. The turntable device according to a third aspect is the device according to the second aspect, wherein the female screw portion is formed to extend in a radial direction on an outer peripheral surface of the turntable. In this device, since the weight member moves in the radial direction and is screwed into the female screw portion, the position of the center of gravity of the turntable can be adjusted steplessly.

[0012] The turntable device according to claim 4 is
In the apparatus according to any one of claims 1 to 3, a plurality of weight members are mounted on the turn table. In this device, since the center of gravity of the turntable is decentered by the plurality of weight members, the position of the center of gravity of the turntable can be easily adjusted.

[0013]

FIG. 1 shows a turntable device 1 employing a first embodiment of the present invention. The turntable device 1 is a device for rotating a disc 3 such as a CD or MD, and includes a turntable 3, a weight 4, a spindle motor 5, a bearing 7, and a motor bracket 15.
And a side pressure spring 9.

The turntable 3 is a disk-shaped member on which the center of the disk 3 is placed. The weight 4 is attached to the outer peripheral area 3 a of the turntable 3. For this reason, the center of gravity of the turntable 3 is eccentric toward the outer peripheral region 3a. As shown in FIGS. 2 and 3, the weight may be attached to a plurality of positions on the turntable 3, and the arrangement position is not particularly limited.

The spindle motor 5 comprises a rotating shaft 11 extending in a vertical direction, and a motor body 13 for driving the rotating shaft 11 to rotate. The tip of the rotating shaft 11 is connected to the center of the turntable 3 so that the rotating shaft 1
1 and the turntable 3 can be integrally rotated.
The bearing 7 is a member for supporting the rotating shaft 11 of the spindle motor 5. The bearing 7 is provided with a bearing hole 7a, and the rotating shaft 11 is disposed through the bearing hole 7a.
On the outer peripheral surface of the bearing 7, a locking groove 7b that is locked to the end of the side pressure spring 9 is formed over the entire circumferential direction.

The motor bracket 15 is mounted on the motor body 13.
And has a portion extending upward to a side position of the rotating shaft 11. In this portion, a locking groove 15a for locking the end of the side pressure spring 9 is formed. The side pressure spring 9 is a member formed of a coil spring for biasing the bearing 7 to the side, and is attached in an extended state to bias the bearing 7 toward the motor bracket 15. An arc-shaped locking portion 9 a is formed at one end of the side pressure spring 9, and the locking portion 9 a is extended over a locking groove 7 b of the bearing 7. At the other end of the side pressure spring 9, a locking portion 9b that can be locked in the locking groove 15a is formed.

Next, the operation of the turntable device 1 will be described. When the disk 17 is placed on the turntable 3 and reproduction of the disk 17 is instructed from the operation unit of the disk player, the spindle motor 5 is driven to rotate the rotating shaft 11. Thereby, the turntable 3 rotates and the disk 17 rotates. Then, a tracking servo of the disk 17 is performed by a control unit (not shown), and information on the disk 17 is read by a pickup (not shown).

At this time, the bearing 7 receives the urging force of the side pressure spring 9 and presses the rotating shaft 11 of the spindle motor 5 toward the motor bracket 15, so that the motor body 13 and the rotating shaft 11 rattle. Can be suppressed. Further, since the center of gravity of the turntable 3 is eccentric by the weight 4, the rotating shaft 11 of the spindle motor 5 rotates with blur. As a result, low-frequency vibration is generated, but high-frequency vibration is suppressed. Generally, turntable device 1
When the frequency of the vibration generated is low, the servo following characteristics of the pickup have more margin than when the frequency of the vibration is high. Therefore, according to the turntable device 1 of the present embodiment, it is possible to allow a margin for servo tracking, and to suppress a reading error of the disk 17. Further, according to the turntable device 1, low-frequency vibration is generated irrespective of variations in the manufacturing accuracy of the motor, so that the range of motor selection at the time of assembling the device is widened. Furthermore, since the center of gravity can be decentered by attaching the weight 4 to the turntable 3, an existing turntable can be used.

(Experimental Example) FIG.
5 shows the result of measuring the vibration generated during the reproduction of the disk 17 using. The vertical axis in FIG. 5 indicates amplitude, and the horizontal axis indicates frequency. In FIG. 5, A shows the vibration in the low frequency region, and B
Indicates vibration in a high frequency range. FIG. 6 shows a similar measurement result using a conventional turntable device. FIGS. 6A and 6B show frequency regions corresponding to A and B in FIG. 5, respectively. Comparing these measurement results, the vibration generated when the turntable device 1 of the present embodiment is used is A
6A and 6B, the vibrations are smaller than those of FIGS. In particular, the vibration at B is almost suppressed. Therefore, according to the turntable device 1 of the present invention, it can be said that high-frequency vibration is suppressed.

[Second Embodiment] The following description focuses on differences from the first embodiment. FIG. 4 shows a turntable 3 and a weight 4 according to a second embodiment of the present invention. A female screw portion 3c extending in the radial direction is provided on the outer peripheral surface 3b of the turntable 3.
The weight 4 has a male thread 4a corresponding to the female thread 3c.

The weight 4 is formed by connecting the male screw portion 4a to the turntable 3
It is attached by screwing into the female screw portion 3c of the. At this time, the center of gravity of the turntable 3 can be set to a desired position by screwing the weight 4 to the turntable 3 by an appropriate radial length. [Other Embodiments] (a) On the back surface of the turntable 3, a concave portion may be formed at a predetermined location so that the weight 4 is positioned and mounted.

(B) The method of mounting the weight 4 is not particularly limited to sticking and screwing, but may be other methods such as locking, press-fitting, welding and the like. (C) The turntable driving device 1 of the present invention is not only applied to a disk player for reproducing an optical disk, but is also applicable to a disk player for reproducing a magnetic disk such as a hard disk or another disk-shaped disk. Can also be applied.

(D) Turntable driving device 1 of the present invention
The disc player to which is applied is not limited to a disc player that only plays a disc, but can also be applied to a recordable disc player.

[0024]

According to the present invention, since the center of gravity of the turntable is formed eccentrically, it is possible to suppress the occurrence of high-frequency vibrations when driving the motor.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view showing a turntable device according to an embodiment of the present invention.

FIG. 2 is a bottom view showing a turntable of the turntable device.

FIG. 3 is a bottom view showing a turntable of the turntable device.

FIG. 4 is a side view of a vertical section and a weight of a turntable according to a second embodiment of the present invention.

FIG. 5 is a diagram showing a waveform of vibration generated by the turntable device of the present invention.

FIG. 6 is a diagram showing a waveform of vibration generated by a conventional turntable device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Turntable device 3 Turntable 3a Outer peripheral area 4 Weight 5 Spindle motor 17 Disk

Claims (4)

[Claims] 1. A turntable device for rotating a disk-shaped disk, comprising: a turntable on which the disk is mounted; a weight member mounted on an outer peripheral area of a part of the turntable; A motor for rotationally driving the turntable. 2. The turntable device according to claim 1, wherein a male screw portion is formed on the weight member, and a female screw portion on which the weight member is mounted is formed on the turntable. 3. The turntable device according to claim 2, wherein the female screw portion is formed to extend in a radial direction on an outer peripheral surface of the turntable. 4. The turntable device according to claim 1, wherein a plurality of said weight members are mounted on said turntable.