JPH10208366A - Disk drive - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To suppress unnecessary vibration during rotation of a disk without significantly increasing cost. SOLUTION: In a disk drive device 1, a rotating means 3 for rotating a disk 2 and a holding means 5 for holding the disk 2 between the rotating means 3 are provided. Then, an additional vibration system 4 ′ including the holding means 5 is attached to the rotary vibration system 4 including the disk 2 and the rotating means 3, and the natural frequency of the additional vibration system is substantially equal to the rotation frequency of the disk 2. Set to a value. As a result, unnecessary vibration of the rotary vibration system 4 (main vibration system) during disk rotation is dynamically absorbed by vibration of the additional vibration system 4 '.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk drive device capable of reducing unnecessary vibration generated when a disk is rotated without a significant increase in cost.

[0002]

2. Description of the Related Art In an apparatus using a disk as a recording medium, it is necessary to minimize unnecessary vibrations during rotation of the disk.

For example, in a disk in which the center of gravity of the disk is designed as designed, there is no problem if the disk is rotated around the center of gravity. When using a disk, when the disk is rotating (for example, at high speed)
In some cases, unnecessary vibration may occur, and if the vibration is excessive, an adverse effect may be caused on devices around the disk drive.

For example, when a computer system incorporates a hard disk drive or a CD-ROM drive as an external storage device, a CD-ROM
Rotational vibration of the disk in the drive device may be transmitted to the hard disk drive device to adversely affect the recording and reproduction of information, or vibration noise may occur when the disk rotates.

In order to reduce the influence of external vibration, the frame or chassis of the disk drive is made of a metal material to make it heavy, or a case or bottom plate which is an outer case is used. Is formed from a sheet metal material, and the thickness of the sheet is increased to increase the weight to obtain a vibration damping effect.

[0006]

However, in the above method, there is a problem that the design of the entire device needs to be reconsidered, and the cost increases.

SUMMARY OF THE INVENTION It is an object of the present invention to suppress unnecessary vibration during disk rotation without a significant increase in cost.

[0008]

According to the present invention, in order to solve the above-mentioned problems, an additional vibration system including the holding means is provided for a rotary vibration system including a disk and a rotating means, and the additional vibration system is provided. The natural frequency is substantially equal to the rotation speed of the disk.

Therefore, according to the present invention, by vibrating the additional vibration system added to the rotary vibration system,
Unwanted vibration of the rotary vibration system can be dynamically absorbed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 conceptually shows the basic structure of a disk drive according to the present invention. The disk drive 1 comprises a rotary vibration system 4 including a disk 2 and a rotating means 3 thereof. Have. It should be noted that the disk 2 includes ones according to all recording systems such as magnetic recording and magneto-optical recording. The rotating means 3 includes all components related to the rotation control of the disk 2, such as a drive source such as a spindle motor and a control system such as a motor driver.

The holding means 5 is required to hold the disk 2 between the rotating means 3 and includes, for example, a chucking plate and a clamper. Holding means 5
Constitutes an additional vibration system with respect to the rotary vibration system 4.

Here, the "additional vibration system" means a vibration system added to the main vibration system for dynamic absorption in forced vibration having two degrees of freedom. For example, as shown in FIG. ,
For a main vibration system having a mass M and an elastic coefficient K (the damping coefficient is omitted in the figure), a mass m and an elastic coefficient k
By adding the above vibration system, the vibration system of mass m vibrates when an external force is applied, but the vibration system of the main vibration system can be stopped. In this case, the natural frequency of the additional vibration system needs to be equal to the frequency ω of the external force.

In the configuration shown in FIG. 1, the rotary vibration system 4 corresponds to the main vibration system, whereas an additional vibration system 4 'including the holding means 5 is provided. It is set so as to be equal to or substantially equal to the number of rotations (that is, the frequency of rotation).

Although such dynamic absorption is effective for a specific frequency ω, resonance at resonance points located on both sides of the dynamic absorption causes a problem. As shown in FIG. 2, the vibration damping member 6 may be interposed between the main vibration system and the additional vibration system.

For example, in FIG. 1, damping members 6 and 6 (these often actually also function as members having the elastic coefficient k) are provided between the disk 2 and the holding means 5. At the same time, they are fixed to the holding member by an appropriate method such as adhesion. As the material of the damping member 6, rubber or foamable urethane (for example, high-density microcell polymer foam, PORON (trade name of Rogers Inoac)) or the like can be used. By selecting the material of the damping member 6, the natural frequency of the additional vibration system 4 'can be freely set to some extent, and there is an advantage that it is only necessary to attach the damping member 6 to the existing holding means.

The chucking member 5 constituting the holding means 5
A can be formed by attaching a predetermined weight to a member made of a synthetic resin, but it is simple to form a member using a material having a high specific gravity (for example, a metal material). It is preferable in terms of conversion.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a CD-ROM drive will be described below with reference to FIGS. Incidentally, the CD-ROM drive has recently been remarkably tended to rotate at a high speed, and it is necessary to take the above-described countermeasures against vibration.

FIG. 3 shows a configuration of a main part of the CD-ROM drive device 7. The base unit 8 includes a spindle motor 9 and an optical reading system 10 (optical head 10a).
And its driving mechanism 10b. ) Is provided.

As shown in FIG. 4, the spindle motor 9 has a chucking table 12 on which the disk 11 is mounted, and a chuck 11 fitted in a circular hole 11a formed in the center of the disk 11. A king yoke 13 is provided.

The chucking portion 14 corresponding to the holding means 5 is rotatably supported by a case body (not shown), and includes a chucking pulley 15 (corresponding to the chucking member 5a) and a vibration damping member. 16, a magnet 17, and a yoke plate 18.

The chucking pulley 15, which is formed in a substantially dish shape by a metal material, has a disk portion 19 in which a circular hole 15a is formed in the center as shown in the figure, and a portion near the outer peripheral edge thereof is formed. The peripheral wall portion 20 is formed by being bent at a predetermined angle, and the magnet 17
And an annular mounting wall 21 for mounting the yoke plate 18
Are formed around the circular hole 15a with a diameter slightly larger than the diameter of the circular hole 15a.

The vibration damping member 16 is formed in a ring shape, and a part thereof is formed on the surface of the disk portion 19 facing the chucking table 12 as shown in FIG. It is fixed to the disk portion 19 using a double-sided adhesive tape 23 in a state of being received in the formed annular concave portion 22.

The disk-shaped magnet 17
The magnet 17 is received in the concave portion 21a formed by the mounting wall 21, and the magnet 17 is prevented from detaching from the mounting wall 21 by mounting a yoke plate 18 having a locking portion from above. In addition to the method of providing the magnet 17 separately from the chucking pulley 15 and the method of magnetizing a predetermined portion of the chucking pulley 15 as described above, the same magnetization as that of the magnet 17 is given to reduce the number of parts. The reduction may be achieved.

When chucking the disk 11, the disk 11 is held between the chucking pulley 15 and the chucking table 12 with the chucking yoke 13 fitted in the circular hole 11a of the disk 11. That is, the magnet 17 and the chucking yoke 1
The disk 11 is sandwiched between the vibration damping member 16 and the chucking table 12 by a magnetic attraction force acting between the chucking section 3 and the chucking section. 14, disc 11, and chucking table 12 rotate integrally.

For example, when the rotation speed of the spindle motor 9 is about 6000 rpm (100 Hz) (a drive device of 12 times speed), the chucking unit 1
The material, configuration, and the like of the disk portion 19 and the vibration damping member 16 are designed so that the natural frequency of the additional vibration system 4 is approximately 100 Hz. Thus, even if the center of gravity of the disk is deviated from the specified position, the vibration of the additional vibration system including the chucking portion 14 contributes as an anti-phase vibration component to the rotational vibration system of the disk 11. Unnecessary vibration during disk rotation can be reduced by the principle of dynamic absorption described above.

The rotation speed of the disk is CLV
(Constant Liner Velocity) method (constant linear velocity method) or CAV (Constant Line Velocity) method.
An angular velocity (constant angular velocity) method can be used, but the latter method, in which the rotation speed is guaranteed to be constant, is more effective because the vibration frequency is constant.

[0027]

As is apparent from the above description, according to the first aspect of the present invention, unnecessary vibration of the rotary vibration system is reduced by vibrating the additional vibration system added to the rotary vibration system. Dynamic absorption can provide a vibration damping effect on the rotary vibration system (especially effective when the number of rotations of the disk is constant). And
Therefore, it is only necessary to provide an additional vibration system including the disk holding means, and it is not necessary to increase the weight of the mechanical structure of the disk drive device, so that there is no significant increase in cost. In addition, since unnecessary vibration can be reduced at the source of the rotational vibration, vibration control measures for other components of the disk drive device become unnecessary or the vibration control measures are reduced.

According to the second aspect of the present invention, by providing the vibration damping member interposed between the disk and the holding means, the natural frequency of the additional vibration system can be set by selecting the material of the vibration damping member. And the vibration damping effect can be obtained with a simple configuration in which a vibration damping member is attached to the holding means.

According to the third and fourth aspects of the present invention,
By forming the chucking member as a single member using a material having a high specific gravity, the configuration of the holding unit can be simplified.

[Brief description of the drawings]

FIG. 1 is a diagram conceptually showing a basic configuration of a disk drive device according to the present invention.

FIG. 2 is a principle diagram for explaining dynamic absorption.

3 shows an embodiment according to the present invention together with FIG. 4, and FIG. 3 is a perspective view showing a main part.

FIG. 4 is a view showing a cross section of a chucking portion and a spindle motor to show a chucking state of a disk.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Disk drive device, 2 ... Disk, 3 ... Rotation means,
4 ... rotational vibration system, 4 '... additional vibration system, 5 ... holding means, 5
a: Chucking member, 6: Damping member

Claims (4)

[Claims] 1. A disk drive device comprising: a rotating means for rotating a disk; and a holding means for holding the disk between the rotating means and a rotating vibration system including the disk and the rotating means. A disk drive device provided with an additional vibration system including the holding means, and a natural frequency of the additional vibration system is set substantially equal to a rotation speed of the disk. 2. The disk drive according to claim 1, further comprising a vibration damping member interposed between the disk and the holding means. 3. The disk drive device according to claim 1, wherein the chucking member constituting the holding means is formed as a single member from a material having a high specific gravity. 4. The disk drive according to claim 2, wherein the chucking member constituting the holding means is formed as one member from a material having a high specific gravity.