JPH07296546A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To suppress deformation of a magnetic disk at the time of assembly. CONSTITUTION:The parts of spacer rings 12 to 15 which come into contact with magnetic disks are provided with annular outer contact parts 12c, 12e... and annular inner contact parts 12d, 12f.... The part of a clamping ring 18 which come into contact with the magnetic disk 8 is provided with an annular outer contact part 18b and an annular inner contact part 18c. The outside diameters of these annular outer contact parts are set at the same size and the bores are set at the same size. The outside diameters of these annular inner contact parts are set at the same size and the bores are set at the same size.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device, and more particularly to a magnetic disk device suitable for preventing deformation of a magnetic disk.

[0002]

2. Description of the Related Art Conventionally, a spindle motor assembly and a magnetic disk assembly which constitute a magnetic disk device have a spindle shaft 5 fixed to a substrate 50 as shown in FIG.
1, a stator 52 fixed to the outer peripheral portion of the spindle shaft 51, and a spindle hub 55 rotatably supported on the outer peripheral side of the spindle shaft 51 via bearings 53 and 54 and having a flanged magnetic disk receiving portion 55a. And the rotor magnet 56 fixed to the inner peripheral wall of the spindle hub 55.
, Magnetic disks 57, 58, 59, 60 fixed to the outer peripheral portion of the spindle hub 55, and the magnetic disks 57 to
60 and an annular spacer ring 61, 62, 63, 64 inserted between the spindle hub 55 and an annular clamper 67 fixed to the spindle hub 55 via screws 65, 66. .

The aforementioned spindle shaft 51 and stator 5
2, the rotor magnet 56 constitutes a spindle motor assembly, and the above-mentioned magnetic disks 57, 58, 59, 6
0, the spacer rings 61, 62, 63, 64, the spindle hub 55, and the clamper 67 constitute a magnetic disk assembly.

The clamper 67 is the highest magnetic disk 5.
7 is configured as a flat bottom surface (see FIG. 5) that comes into contact with the top surface, and the spacer rings 61 to 64 are top surfaces that come into contact with the respective surfaces of the magnetic disks 57 to 60 and the magnetic disk receiving portion 55a of the spindle hub 55. The lower portion and the lower portion are configured as flat surfaces (see FIG. 6). Reference numerals 67a and 67b in FIG. 5 indicate screw holes. Magnetic disks 57-6
When fixing 0 to the outer periphery of the spindle hub 55,
The disks 57-60 are alternately laminated via the spacer rings 61-64, and the clamper 67 is tightened and fixed to the spindle hub 55 with the screws 65, 66, whereby the disks 57-60 and the spacer rings 61-64 are fixed to the spindle hub 55. It is designed to be held and fixed on.

[0005]

However, in the above-mentioned conventional magnetic disk device, the disk contact surfaces of the spacer rings 61 to 64 are formed as flat surfaces, and the disk contact surfaces of the clampers 67 are also flat surfaces. Since the clamper 67 is configured as
When the pressing load due to the tightening force of the clamper 67 is irregularly applied to the disk abutting surface when it is fixed to the spindle hub 55 by 6, the magnetic disks 57 to 60 on the outer peripheral portion of the spindle hub 55 are accordingly accompanied. There is a problem in that a warp (warp up / warp down) occurs and it is deformed. This was particularly remarkable in the highest and lowest magnetic disks.

When a warp occurs in the magnetic disks 57-60, when a magnetic head (not shown) writes / reads information to / from the disks 57-60, distortion occurs in a write waveform and a read waveform, a so-called modulation phenomenon. However, there is a problem that proper writing / reading cannot be performed. In addition, the magnetic disks 57-6
If the warp of 0 is further increased, it becomes impossible to secure a predetermined gap between the magnetic head and the magnetic disks 57-60 during standby or seek operation of the magnetic head. There is a problem that a so-called head crash phenomenon occurs in contact with the magnetic disk device and the reliability of the magnetic disk device is deteriorated.

[0007]

It is an object of the present invention to improve the disadvantages of the above-mentioned conventional example, and in particular, to suppress the deformation of the magnetic disk at the time of assembly so that the writing / reading waveform by the magnetic head is distorted and the magnetic disk is prevented. It is an object of the present invention to provide a magnetic disk device that prevents the phenomenon that a magnetic head makes contact.

[0008]

SUMMARY OF THE INVENTION The present invention provides a cylindrical spindle hub which is rotatably supported by a spindle shaft via a bearing and has a collar-shaped magnetic disk receiving portion at one end thereof. A plurality of magnetic disks stacked on the outer peripheral portion of the spindle hub via an annular spacer member, and mounted on the other end of the spindle hub, and cooperates with the magnetic disk receiving portion of each of the magnetic disks. In a magnetic disk device provided with a disk-shaped clamp member that holds and holds a radially inner portion in the magnetic disk stacking direction, in the radial center portion of the magnetic disk contact surface of the clamp member, the circumference of the clamp member is provided. An annular groove portion is provided along the direction, and the annular portion is formed along the circumferential direction of each spacer member at the radial center portion of the magnetic disk contact surface of each spacer member. That the groove is provided respectively, and employs a configuration that. This aims to achieve the above-mentioned object.

[0009]

According to the invention, the pressing force generated by the clamping member is divided into equal pressing forces on the annular outer part and the annular inner part formed by the annular groove of the clamping member, which outer part and inner part. An equal pressing force is applied to the innermost side portion of the uppermost magnetic disk via. Further, the pressing force applied from the clamp member to the inner peripheral side portion of the uppermost magnetic disk is applied to the magnetic disk of the spindle hub via the annular outer portion and annular inner portion formed by the annular groove portion of the spacer member. Each is transmitted to the receiving portion. That is, the pressing force of the clamp member is applied as an equal force to the annular outer portion and the annular inner portion formed by the annular groove portion of the spacer member. Therefore, with respect to the radially inner portion of the magnetic disk, the annular outer portion formed by the annular groove portion of the clamp member, the contact point between the annular inner portion and the radially inner portion of the magnetic disk, and the magnetic disk Equal forces are always applied via the contact points between the radially inner part and the outer and inner parts formed by the grooves of each spacer member.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of the main part of the magnetic disk device according to the present embodiment. The spindle shaft 2 is fixed to the substrate 1, the stator 3 is fixed to the outer peripheral portion of the spindle shaft 2, and the spindle. A substantially cylindrical spindle hub 6 rotatably supported on the outer peripheral side of the shaft 2 via bearings 4, 5, a rotor magnet 7 fixed to an inner peripheral wall portion of the spindle hub 6, and an outer peripheral portion of the spindle hub 6. Magnetic disks 8, 9, 10, 11 fixed to the disk and annular spacer rings 12, 1 interposed between the magnetic disks and between magnetic disk receiving portions (described later) of the spindle hub 55.
3, 14, 15 and screws 16, 17 on the spindle hub 6.
And a ring-shaped clamp ring 18 fixed via the.

The above-mentioned spindle shaft 2, stator 3 and rotor magnet 7 constitute a spindle motor assembly,
The magnetic disks 8, 9, 10, 11 described above, the spacer rings 12, 13, 14, 15, the spindle hub 6, and the clamp ring 18 constitute a magnetic disk assembly.

The lowermost portion of the spindle hub 6 is provided with magnetic disks 8-11 via spacer rings 12-15.
Is formed as a brim-shaped magnetic disk receiving portion 6A, and the spacer ring 15 contact surface of the magnetic disk receiving portion 6A is formed as a flat surface.

As shown in FIG. 2, the clamp ring 18 has a groove portion 1 continuous in an annular shape along the circumferential direction of the lower surface thereof.
8a is formed, whereby the outer side and the inner side of the groove portion 18a are configured as an annular outer abutting portion 18b and an annular inner abutting portion 18c that abut the upper surface of the uppermost magnetic disk 8. The outer abutting portion 18b and the inner abutting portion 18c of the clamp ring 18 press the inner peripheral upper surface portion of the uppermost magnetic disk 8. Reference numerals 18d and 18e in the figure denote screw holes.

As shown in FIG. 3, the spacer ring 12 is formed with groove portions 12a and 12b, which are continuous in an annular shape along the circumferential direction of the upper surface portion and the lower surface portion, respectively, whereby the outside and inside of the groove portion 12a are formed. Is configured as an annular outer abutment portion 12c and an inner abutment portion 12d that abut on the inner peripheral side lower surface portion of the uppermost magnetic disk 8, and
The outer side and the inner side of the groove 12b are configured as an annular outer abutting portion 12e and an annular inner abutting portion 12f that come into contact with the upper surface of the magnetic disk 9. Other spacer ring 13
˜15 also have the same structure as the spacer ring 12.

The groove portion 18 of the clamp ring 18 described above.
a, grooves 12a, 12b of each spacer ring 12-15
The widths of .. are formed to have the same size. In other words,
Outer contact part 18b of clamp ring 18, inner contact part 1
8c and the outer contact portion 12 of each spacer ring 12-15
c, 12e ..., Inner contact portions 12d, 12f, ... Have the same sectional shape, and the outer contact portions have the same outer diameter and the same inner diameter. The inner contact portions are formed to have the same outer diameter and the same inner diameter.

The magnetic disks 8 to 11 are attached to the spindle hub 6.
When the magnetic disks 8 to 11 are alternately stacked via the spacer rings 12 to 15 and the clamp ring 18 is fixed to the spindle hub 6 with screws 16 and 17, the magnetic disks 8 to 11 are fixed to the outer peripheral portion of the magnetic disk. Disk 8-
11 and spacer rings 12 to 15 to the spindle hub 6
It is designed to be held and fixed on.

Next, the operation of this embodiment constructed as described above will be described.

Magnetic disks 8-11 and spacer rings 12-15 are tightened and fixed to the spindle hub 6 of the spindle motor assembly of the magnetic disk device with screws 16 and 17 via clamp rings 18, whereby the magnetic disk assembly is assembled. When assembled, the clamp ring 18
The pressing force generated by the ring-shaped outer contact portion 18b formed by the ring-shaped groove portion 18a of the clamp ring 18 is
And the annular inner contact portion 18c is divided into equal pressure forces, and the same pressure force is applied to the inner peripheral side portion of the uppermost magnetic disk 8 through the outer contact portion 18b and the inner contact portion 18c.

Further, the pressing force applied from the clamp ring 18 to the inner peripheral side portion of the uppermost magnetic disk 8 is an annular outer contact portion formed by the annular grooves 12a and 12b of the spacer rings 12-15. 12c, 12e ...
.. is transmitted to the magnetic disk receiving portion 6A of the spindle hub 6 via the annular inner contact portions 12d, 12f.

That is, the outer contact portion 1 of the clamp ring 18
8b, inner contact portion 18c, and spacer rings 12 to 1
5, outer contact portions 12c, 12e ..., Inner contact portion 12
.. are arranged so as to face each other via the magnetic disks 8 to 11, so that the pressing force of the clamp ring 18 causes the outer contact portions 12 of the spacer rings 12 to 15 to contact.
c, 12e ..., And inner contact portions 12d, 12f ...

Therefore, for the magnetic disks 8-11, the magnetic disks 8-11 and the spacer rings 12-1 are used.
5, outer contact portions 12c, 12e ..., Inner contact portion 12
Since the same force is always applied through the contact points with d, 12f ..., The magnetic disks 8 to 11 are held in parallel by the clamp ring 18 and the spacer rings 12 to 15. As a result, it is possible to prevent the magnetic disks 8 to 11 from being deformed and warped up or down.

As described above, according to the present embodiment, the clamp ring 18 and the annular groove portions of the spacer rings 12 to 15 are arranged to face each other in the magnetic disk stacking direction. The clamp ring 18 and the spacer rings 12 to 15 are attached to the radially inner portion.
As a result that a uniform pressing force is always applied through the contact points with the annular outer abutment portion and the annular inner abutment portion formed by the annular groove portions 18a, 12a, 12b, ... 11 can be held in a horizontal state by the clamp ring 18, the spacer rings 12 to 15 and the magnetic disk receiving portion 6A of the spindle hub 6, and as a result, the deformation of the magnetic disks 8 to 11 can be prevented. This makes it possible to prevent a so-called modulation phenomenon in which a write waveform or a read waveform is distorted when information is written in or read from the magnetic disks 8 to 11 by a magnetic head (not shown). Writing / reading can be performed.

Further, according to this embodiment, since the magnetic disks 8 to 11 can be prevented from being deformed as described above, the magnetic head and the magnetic disk 8 are in standby or seek operation.
As a result, a so-called head crash phenomenon in which the magnetic head comes into contact with the magnetic disk can be prevented as a result of securing a predetermined gap between the magnetic disk and the magnetic disk, and thus the reliability of the magnetic disk device can be improved. .

Further, according to this embodiment, the clamp ring 18 and the annular groove portions 18a of the spacer rings 12 to 15,
The above effect can be obtained by holding and pressing the magnetic disks 8 to 11 through the annular outer abutment portion and the annular inner abutment portion formed by 12a, 12b ... It is not necessary to insert a top spacer ring between the uppermost magnetic disk 8 and the topmost magnetic disk 8. As a result, the number of parts can be reduced and the cost can be reduced especially in mass production.

Further, according to this embodiment, it is not necessary to insert the top spacer ring between the clamp ring 18 and the uppermost magnetic disk 8 as described above.
Assembling work of the magnetic disk assembly is facilitated, and as a result, productivity can be improved especially in mass production.

[0027]

As described above, according to the magnetic disk device of the present invention, the groove portion which is annularly continuous along the circumferential direction of the clamp member is provided at the central portion in the radial direction of the magnetic disk contact surface of the clamp member. Since a groove portion that is annularly continuous along the circumferential direction of each spacer member is provided in the radial center portion of the magnetic disk contact surface of each spacer member, the clamp member and each spacer are attached to the radially inner portion of the magnetic disk. Since the same force is always applied via the contact points with the annular outer portion and the annular inner portion formed by the groove portion of the member, each magnetic disk is clamped, each spacer member, and the magnetic disk of the spindle hub. As a result of being held horizontally by the receiving portion, it is possible to prevent the magnetic disk from being deformed. When performing the writing and reading of information to disk, it is possible to prevent a so-called modulation phenomenon distortion in the write waveform and reading the waveform, thus, it is possible to perform proper writing / reading. Also,
As described above, since the deformation of the magnetic disk can be prevented, a predetermined gap is secured between the magnetic head and the magnetic disk during standby or seek operation of the magnetic head, resulting in a so-called head crash in which the magnetic head contacts the magnetic disk. It is possible to prevent the phenomenon, and thereby to improve the reliability of the magnetic disk device.

Further, according to the magnetic disk device of the present invention, the radial direction of each magnetic disk is passed through the annular outer portion and the annular inner portion formed by the annular groove portions of the clamp member and the spacer member as described above. Since the above effect can be obtained by applying the uniform pressing force to the inner portion, it is not necessary to insert the top spacer member between the clamp member and the uppermost magnetic disk,
As a result, the number of parts can be reduced and the cost can be reduced especially in mass production. Furthermore, since it is not necessary to insert the top spacer member between the clamp member and the uppermost magnetic disk as described above, the assembling work of the magnetic disk assembly is facilitated, and as a result, especially in mass production. In the above, there is an effect that productivity can be improved.

Further, in the magnetic disk device of the present invention, when the periphery of the groove portion of the clamp member on the magnetic disk contact side is projected toward the radially inner portion of the magnetic disk, the protruding portion of the clamp member, It is possible to reliably sandwich and hold each magnetic disk in the magnetic disk stacking direction via the spacer member and the magnetic disk receiving portion.

Further, in the magnetic disk device of the present invention, when the width of each groove of the clamp member and each spacer member is set to the same size, each groove is formed on the radially inner part of the magnetic disk. Since even more equal force can be applied from the clamp member via the contact points with the annular outer portion having the same width and the annular inner portion having the same width, the deformation of the magnetic disk is effective as described above. The effect is that it can be prevented.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a configuration of a magnetic disk assembly and a spindle motor assembly of a magnetic disk device according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view showing the structure of a clamp ring in this embodiment.

FIG. 3 is a vertical cross-sectional view showing the structure of a spacer ring in this embodiment.

FIG. 4 is a vertical cross-sectional view showing a configuration of a magnetic disk assembly and a spindle motor assembly of a conventional magnetic disk device.

FIG. 5 is a vertical sectional view showing a configuration of a clamper in a conventional example.

FIG. 6 is a vertical sectional view showing a structure of a spacer ring in a conventional example.

[Explanation of symbols]

2 spindle shafts 3, 4 bearings 6 spindle hubs 6A magnetic disk receiving portions 8, 9, 10, 11 magnetic disks 12, 13, 14, 15 spacer rings as spacer members 12a, 12b groove portions 18 clamp rings as clamp members 18a groove portions

Claims (3)

[Claims] 1. A cylindrical spindle hub, which is rotatably supported by a spindle shaft via a bearing and has a flange-shaped magnetic disk receiving portion at one end, and an annular ring on the outer peripheral portion of the spindle hub. A plurality of magnetic disks stacked via a spacer member, and the other end of the spindle hub are mounted on the other end of the magnetic disk. In a magnetic disk device including a disk-shaped clamp member that clamps and holds the magnetic disk in a direction, a groove portion that is annularly continuous along the circumferential direction of the clamp member at the radial center portion of the magnetic disk contact surface of the clamp member. Each of the spacer members is provided with a groove portion continuous in an annular shape along the circumferential direction of the spacer member at the radial center portion of the magnetic disk contact surface. DOO magnetic disk apparatus characterized by. 2. The magnetic disk device according to claim 1, wherein a periphery of a groove portion on the magnetic disk contact side of the clamp member is provided so as to project toward a radially inner portion of the magnetic disk. 3. The magnetic disk drive according to claim 1, wherein the width of each groove of the clamp member and each spacer member is set to be the same.