JPH08335348A - Disk holding mechanism - Google Patents

Abstract

PURPOSE: To enable working of the disk holding mechanism at low cost and to obtain the mechanism of high performance and high reliability by providing three projecting parts at angular intervals of 120 deg. on a disk mounting surface of a turntable and holding a disk thereon. CONSTITUTION: The turntable 1 is constituted integrally with a spindle motor 2, and its upper surface is formed with the three projecting parts provided at angular intervals of approximately 120 deg., constituting one flat plane to be surely decided at the time of mounting the disk 6. A magnet 5 is embedded in the turntable 1, while a metal plate to be attracted by the magnet is stuck to the inside of a clamper 4, and the disk 6 is held between both sides of them as the upper and lower parts. At this time, the disk 6 is brought into contact with the three projecting parts on the turntable 1, and is stably held. Consequently, the performance of the disk holding mechanism can be enhanced particularly for a high speed CD-ROM disk device of more than quadruple the speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc holding mechanism in an information processing apparatus for recording or reproducing using a disc such as an optical disc and a magnetic disc, and more particularly to stable disc holding when the disc is rotated at a high speed. The present invention relates to a disk holding mechanism suitable for improving the property.

[0002]

2. Description of the Related Art In recent years, recording or reproducing apparatuses using disks such as optical disks and magnetic disks are rapidly becoming widespread due to the progress of large capacity, high density recording and high speed access. In such a situation, in order to realize even higher speed access, taking a CD-ROM device as an example, double speed,
As the speed is increased to 4 times and 8 times, the disk rotation speed is also increased to 2, 4, and 8 times. Here, as described in JP-A-2-223056 and JP-A-3-185669, the disk is usually held by being sandwiched by a turntable and a clamper, and is rotationally driven by a spindle motor integrated with the turntable. It is structured to do.

For example, in a CD-ROM device, since the peripheral speed of the disk is constant with respect to the pickup section for recording or reproducing information, the number of revolutions of the disk changes depending on the radial position for recording or reproducing. In the seek mode, the disk rapidly repeats acceleration and deceleration. At this time, since the disk has a unique frequency, it is excited by the rotation of the spindle motor, causing resonance.
It may be impossible to exchange signals with the pickup.

Here, the shape of a conventional turntable is shown in FIG. FIG. 7A is a perspective view of the turntable, FIG.
(B) shows the same top view. Although the disc has a structure in contact with the mounting surface 50a of the turntable, if the flatness of the entire mounting surface is not secured, as shown by the hatched portion in FIG. The point 50b can be contacted, and the mounting surface changes every time the disk is accelerated or decelerated. As a result, the holding of the disk becomes unstable and resonance is likely to occur.

[0005]

As described above, the conventional turntable has a problem that it is difficult to secure the flatness of the disk mounting surface and the disk cannot be stably held at high speed rotation. Further, if it is attempted to secure the flatness of the mounting surface over the entire mounting surface 50a shown in the conventional example of FIG. 7A, there is a problem that the processing requires high accuracy and the cost becomes high.

Further, since rapid deceleration is repeated during high-speed access, which is a characteristic of an information recording / reproducing apparatus using a disc, when the disc holding condition is bad, especially, other than three points on the mounting surface of the turntable. When the disc is held at, the disc holding surface becomes unstable. At this time, the rotation of the spindle motor excites the disk, which causes high-frequency disk resonance, making it impossible to exchange signals with the pickup.

An object of the present invention is to provide a disk holding mechanism of low cost, high performance and high reliability in order to solve the above problems.

[0008]

In order to solve the above problems, the present invention is characterized by having the following configuration.

(1) Three convex portions are provided on the disk mounting surface of the turntable.

(2) Spacer members are attached to three places on the disk mounting surface of the turntable.

[0011]

Since the disk is supported at three points, a stable flat surface can be easily formed, and the disk can be stably held even at high rotation.

[0012]

Embodiments of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is a schematic perspective view of a holding mechanism portion of a 12 cm CD-ROM disc which is a kind of optical disc according to the present invention, and FIG. 2 is a sectional view of the holding mechanism. The turntable unit 10 is composed of a turntable 1 and a spindle motor 2, and the turntable 1 is press-fitted onto a shaft 2a of the spindle motor 2 to be integrally formed. Also,
Three convex portions 1a are formed on the upper surface of the turntable at approximately 120 ° intervals, and one plane is surely determined when the disc is mounted.

The disk 6 is carried onto the turntable 1 by a disk transfer means (not shown), and then the disk 6 and the clamper 4 descend relative to the turntable 1. Here, since the magnet 5 is embedded in the turntable and the metal plate attracted to the magnet is adhered inside the clamper 4, the disc 6 can be held by being sandwiched from both upper and lower surfaces. Complete. At this time, the disc is in contact with the three convex portions 1a on the turntable and forms only one plane, so that the disc is stably held.

Subsequently, the spindle motor starts to rotate by a drive circuit (not shown), and a pickup (not shown) records and reproduces a signal from the disc. Since the CD-ROM disc described in this embodiment has a constant peripheral speed with respect to the pickup, the disc rotation speed is about 477 rpm (innermost circumference of the pickup position) at the time of 1 × speed access.
217 rpm (same outermost circumference), approx. 19 at 4x speed access
Although it varies from 10 rpm to 868 rpm from moment to moment, when the disc is placed by the three convex portions on the turntable as described in this embodiment, the disc can be stably held, so that the resonance is sufficiently suppressed and the stable signal is obtained. Can be exchanged.

Here, as means for forming the three convex portions,
Molding of the turntable as a unit, shaving from the material of the turntable, embossing with a press, etc.
There is a method of masking so that the dots are exposed, then applying a coating agent with, for example, a urethane-based resin, peeling off the masking to form three convex portions, and a method of forming convex portions by etching similarly.

By using the disk holding method as described above, a stable surface is formed only by forming three convex portions having a small area. Further, since it is integrally formed with the turntable, when the disk rotates at high speed, or Even when loading or unloading a disc, the protrusions do not peel off and the adhesive that fixes the protrusions does not elute, so a low-cost, high-performance, highly-reliable disc holding mechanism can be realized. This is effective for improving the performance of the disc holding device of the high speed CD-ROM disc device of double speed or more.

FIG. 3 is a sectional view showing the structure of the second embodiment of the present invention. Here, 1 is a turntable, 1b is a coating part that covers at least three convex surfaces, 2 is a spindle motor, 2a is a spindle motor shaft,
Reference numeral 5 is a magnet 5, 6 embedded in the turntable, and an optical disk capable of reading and writing information.

According to the present invention, in the first embodiment, a coating is applied with a material different from that of the turntable so as to cover at least the three protrusions serving as the disk mounting surface except when the protrusions are formed by the coating agent. Is. When holding the disc as in the present embodiment, even if the disc is rapidly decelerated, slippage between the turntable and the disc is small, and the disc surface is not damaged. In addition to the effects described in the embodiment, it is possible to realize a disk holding mechanism having higher performance and higher reliability.

FIG. 4 is an explanatory diagram showing the configuration of the third embodiment of the present invention. FIG. 4A is a view of the turntable portion of the present invention seen from above, and FIG. 4B is a sectional view of the turntable. In FIG. 4, 11 is a turntable, 2 is a spindle motor, 2a is a spindle motor shaft, 5 is a magnet 5 embedded in the turntable,
6 is an optical disk capable of reading and writing information, 1
Reference numeral 2 denotes three spacer members which are attached to the circumference of the turntable 11 with an adhesive or the like at intervals of approximately 120 degrees.
The material of the spacer member 12 is not particularly limited, and may be the same material as the turntable 11, or may be plastic, metal, felt, paper, coating material made of urethane-based material, or the like.

As with the first and second embodiments, the procedure for holding the disk 6 is such that the disk 6 is carried onto the turntable 1 by the disk transfer means (not shown), and the disk is continued relative to the turntable 1. 6 and the clamper 4 descend. At this time, the positions of the center of the turntable and the disc 6 are determined by the taper rings 7 and 8 for positioning the disc integrally formed with the turntable and the elastic body 9 accommodated in the taper ring 8. Since the magnet 5 is embedded in the turntable 11 and a metal plate attracted to the magnet is adhered to the inside of the clamper 4, the disc 6 is completely held by being sandwiched from both sides. .

According to the structure of the present invention, since the three turntables 15 can be attached on the circumference of the upper surface of the turntable 11 after the entire turntable portion 15 is assembled, a stable surface can be obtained as in the first embodiment. In addition to the effect that can be formed, there is a feature that an optimum material for holding the disc can be easily attached later.

FIG. 5 is an explanatory view showing the fourth embodiment of the present invention. FIG. 5A is a top view of the turntable portion of the present invention, and FIG. 5B is a sectional view of the turntable. In FIG. 5, 11 is a turntable, 2 is a spindle motor, 2a is a spindle motor shaft,
Reference numeral 5 is a magnet 5 embedded in the turntable, 6 is an optical disk capable of reading and writing information, 12 is three spacer members arranged on the circumference of the turntable 11 at approximately 120-degree intervals, and 13 is It is a resin thin film that covers the spacer member 12 and the turntable 11.

Here, the spacer member 12 forming the convex portion
The material of is not particularly limited, and may be the same material as the turntable 11 or may be a coating material such as plastic, metal, felt, paper, or urethane material. For the resin thin film, a material having excellent wear resistance, for example, a polyimide thin film is used.

In the fourth embodiment, by coating the spacer material with a thin film, in addition to the effect of the first embodiment, the spacer member peels off despite the rapid deceleration of the disk. None, there is always the effect that a stable surface is formed by three points.

Although the four embodiments have been described above, the present invention does not limit the shape of the turntable 20 to a circular shape as shown in FIG. 6, but is a three-spoke modification having three installation surfaces 20a. Can also be considered. In the various embodiments described so far, the invention is a CD-R which is a 12 cm optical disc.
The case of application to the OM has been described, but this is not limited to a CD-ROM that can be accessed at high speeds such as 2 × speed, 4 × speed, 8 × speed, 12 × speed, etc., and the application of the present invention is not limited to this. It can be applied to a disk holding mechanism of an information processing apparatus using various disks such as magnetic disks and magneto-optical disks.

[0026]

Since a stable surface is formed only by forming three convex portions having a small area, it is possible to realize a disk holding mechanism which can be processed at low cost and which has high performance and high reliability.

[Brief description of drawings]

FIG. 1 is a perspective view showing a disk holding mechanism of a first embodiment of the present invention.

FIG. 2 is a sectional view showing the configuration of the first exemplary embodiment of the present invention.

FIG. 3 is a sectional view showing a configuration of a second exemplary embodiment of the present invention.

FIG. 4 is a sectional view showing a configuration of a third exemplary embodiment of the present invention.

FIG. 5 is a sectional view showing a configuration of a fourth exemplary embodiment of the present invention.

FIG. 6 is an explanatory diagram showing a configuration of an exemplary embodiment of the present invention.

FIG. 7 is an explanatory diagram of a conventional example.

[Explanation of symbols]

 1, 11, 20 ... Turntable 1a ... Convex portion on turntable 1b ... Coating material 2 ... Spindle motor 4 ... Clamper 6 ... Disk 12 ... Spacer member 13 ... Resin thin film

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masayuki Inoue, 292 Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa, Ltd. Hitachi, Ltd. multimedia system development headquarters (72) Inventor Michio Miura Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa Hitachi, Ltd.Multimedia System Development Headquarters (72) Inventor, Seiichiro Nagai, Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa Prefecture, 292.Hitachi Corporation Multimedia System Development Headquarters (72), Inventor Kuniyuki Kimura 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa, Ltd.Information & Video Division, Hitachi, Ltd. (72) Inventor, Seiji Hamaya, 292, Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa, Ltd., Information & Video Division, Hitachi, Ltd. (72) Inventor Kei Kono Hitachi Co., Ltd.502 Kandamachi, Tsuchiura City, Ibaraki Prefecture Sakusho Mechanical Engineering Research Laboratory within the

Claims (5)

[Claims] 1. A disk holding mechanism comprising a turntable for holding a disk-shaped recording / reproducing medium, a spindle motor for rotating the turntable, and a clamp member for pressing the disk-shaped recording medium against the turntable. A disk holding mechanism, wherein the disk is supported at three points on the disk mounting surface of the turntable. 2. A disk holding mechanism comprising a turntable for holding a disk-shaped recording / reproducing medium, a spindle motor for rotationally driving the turntable, and a clamp member for pressing the disk-shaped recording medium against the turntable. , 3 on the disk mounting surface of the turntable
A disk holding mechanism that is provided with two convex portions. 3. The disk holding mechanism according to claim 2, wherein the convex portion of the turntable is formed by coating a material different from that of the turntable. 4. A disk holding mechanism comprising a turntable for holding a disk-shaped recording / reproducing medium, a spindle motor for rotationally driving the turntable, and a clamp member for pressing the disk-shaped recording medium against the turntable. A disc holding mechanism, wherein spacer members are attached to three places on the disc mounting surface of the turntable. 5. The disk holding mechanism according to claim 4, wherein the spacer member and the turntable are covered with a resin thin film.