JPH07296476A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To suppress deformation of magnetic disks at assembling time by providing projecting parts on projected parts from annular groove parts in a magnetic disk receiving part and top and other individual spacer rings of a spindle hub respectively and a groove part of a clamp ring. CONSTITUTION:The magnetic disk receiving part 6A and the top and following individual spacer rings 17 and 13-16 are provided with their respective annular groove parts 6a, 13a and 13b,... Therefore, the surface of the receiving part 6A and the rings 13-17 to be in contact with the magnetic disks 8-12 are formed with annular outer and inner side contact parts 6b, 6c, 13c-13f,.... Then, the clamp ring 20 is provided with a projection 20a in an approximately hemicycle for pressing a part to be in contact with a V-groove in the back surface of the groove of the ring 17. The hub 6 between the receiving part 6A and the ring 20 is inserted into the individual disks and rings, and the ring 20 is pressingly fixed to the hub 6 by screws 18 and 19. By this method, force is equally impressed upon the individual disks in the radial direction at the time of assembly, thus preventing deformation.

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, 61 fixed to the outer peripheral portion of the spindle hub 55, and annular spacer rings 62, 63, 6 inserted between the magnetic disks.
4, 65 and an annular clamp ring 68 fixed to the spindle hub 55 via screws 66 and 67.

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, 61, spacer rings 62, 63, 64, 65, spindle hub 55, and clamp ring 68 constitute a magnetic disk assembly.

The clamp ring 68 has a flat lower surface that abuts the upper surface of the uppermost magnetic disk 57 (see FIG. 7), and the spacer rings 62 to 65 are connected to the respective surfaces of the magnetic disks 57 to 61. The abutting upper surface portion and lower surface portion are configured as flat surfaces (see FIG. 8). Reference numerals 68a and 68b in FIG. 6 indicate screw holes. Magnetic disk 5
When fixing 7 to 61 to the outer peripheral portion of the spindle hub 55, the disks 57 to 61 are set to spacer rings 62 to 65.
By alternately laminating the clamp ring 68 with the screw 6
The disks 57 to 61 and the spacer rings 62 to 6 can be fixed by tightening and fixing them to the spindle hub 55 with 6, 67.
5 is held and fixed to the spindle hub 55.

[0005]

However, in the above-mentioned conventional magnetic disk device, the disk contact surfaces of the spacer rings 62 to 65 are formed as flat surfaces, and the disk contact surfaces of the clamp rings 68 are also flat. Since it is configured as a surface, when the clamp ring 68 is tightened and fixed to the spindle hub 55 with the screws 66 and 67, the spindle hub 55 is elastically deformed, or the pressing load due to the tightening force of the clamp ring 68 abuts the disk. If it is applied irregularly to the surface, there is a problem that the magnetic disks 57 to 61 on the outer peripheral portion of the spindle hub 55 are warped (warped / warped down) and deformed accordingly. This was particularly remarkable in the highest and lowest magnetic disks.

When the magnetic disks 57 to 61 are warped, when a magnetic head (not shown) writes or reads information to or from the disks 57 to 61, distortion occurs in a write waveform or 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 No. 1 is further increased, it becomes impossible to secure a predetermined gap between the magnetic head and the magnetic disks 57 to 61 during standby or seek operation of the magnetic head, so that the magnetic head moves to the magnetic disks 57 to 61. There is a problem that a so-called head crash phenomenon occurs in which the contact occurs.

[0007]

It is an object of the present invention to improve the disadvantages of the above conventional example, and in particular, to suppress the deformation of the magnetic disk during assembly, thereby causing a phenomenon that the write / read waveform by the magnetic head is distorted and the magnetic disk. It is an object of the present invention to provide a magnetic disk device which prevents the phenomenon that a magnetic head comes into contact with the magnetic disk device.

[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 for holding and holding a radially inner portion in the magnetic disk stacking direction, the magnetic disk is provided at a radial center portion of a magnetic disk contact surface of the magnetic disk receiving portion. An annular groove is provided along the circumferential direction of the receiving portion, and the radial direction central portion of the magnetic disk contact surface of each spacer member is provided along the circumferential direction of each spacer member. A groove portion continuous in an annular shape, and an annular top spacer member is interposed between the clamp member and the uppermost magnetic disk, and at the radial center portion of the magnetic disk contact surface of the top spacer member, A configuration is provided in which a groove portion that extends in an annular shape is provided along the circumferential direction of the top spacer member, and a projecting portion that extends in an annular shape along the circumferential direction of the clamp member is provided at a portion of the clamp member facing the groove portion of the top spacer member. Is taking. This aims to achieve the above-mentioned object.

[0009]

According to the present invention, the pressing force generated by the clamp member is applied to the top spacer member via the annular protrusion of the clamp member. Further, the pressing force applied from the clamp member to the top spacer member is divided into an annular outer portion and an annular inner portion formed by the annular groove portion of the top spacer member. The same pressing force is applied to each. The pressing force equally applied to the outer portion and the inner portion of the groove portion of the top spacer member is equal to the annular outer portion and the inner portion formed by the annular groove portion of each spacer member, and the magnetic disk receiving portion of the spindle hub. It is respectively transmitted to an annular outer portion and an annular inner portion formed by the annular groove portion. Along with this, the pressing force applied from the clamp member to the top spacer member is applied to each annular outer portion and each annular inner portion formed by each spacer member and each groove portion of the magnetic disk receiving portion of the spindle hub. They are applied as equal forces. Therefore, the same force is always applied to the magnetic disk through the contact points with the annular outer portions and the annular inner portions.

[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, 12 fixed to the disk, and an annular spacer ring 13 interposed between the magnetic disks,
14, 15, 16; an annular top spacer ring 17 mounted on the upper surface of the uppermost magnetic disk 8; and an annular clamp ring 20 fixed to the spindle hub 6 via screws 18, 19. Has become.

The above-mentioned spindle shaft 2, stator 3 and rotor magnet 7 constitute a spindle motor assembly,
The magnetic disks 8, 9, 10, 11, 12 described above, the spacer rings 13, 14, 15, 16, the top spacer ring 17, the spindle hub 6, and the clamp ring 20 constitute a magnetic disk assembly.

The lowermost portion of the spindle hub 6 is configured as a collar-shaped magnetic disk receiving portion 6A for supporting the magnetic disks 8-12 and the spacer rings 13-16, and the magnetic disk receiving portion 6A has An annular groove portion 6a is formed along the circumferential direction so that the radially outer side and the radially inner side of the annular groove portion 6a come into contact with the lower surface of the lowest magnetic disk 12 in an annular outer contact portion. 6b and the inner contact portion 6c.

As shown in FIG. 2, the clamp ring 20 is formed with an annular projection 20a along the circumferential direction of the lower surface thereof, and the projection 20a is formed in a semicircular vertical cross-section. ing. The protrusion 20a of the clamp ring 20 presses the annular groove portion 17a of the top spacer ring 17. Reference numeral 20 in the figure
Reference numerals b and 20c denote screw holes.

As shown in FIG. 3, the top spacer ring 17 is formed with a groove portion 17a which is continuous in an annular shape along the circumferential direction of the lower surface portion thereof, whereby the annular groove portion 1 is formed.
The radially outer side and the radially inner side of 7a are configured as an annular outer abutting portion 17b and an inner abutting portion 17c that abut the upper surface of the uppermost magnetic disk 8.

As shown in FIG. 4, the spacer ring 13 is provided with groove portions 13a and 13b which are continuous in an annular shape along the circumferential direction of the upper surface portion and the lower surface portion thereof, respectively, whereby the diameter of the annular groove portion 13a is formed. The outer side and the inner side in the radial direction are configured as an annular outer abutting portion 13c and an inner abutting portion 13d that abut the lower surface of the uppermost magnetic disk 8, and the radial outer side and the radial inner side of the annular groove portion 13b. Are configured as an annular outer contact portion 13e and an inner contact portion 13f that contact the upper surface of the magnetic disk 9. The other spacer rings 14 to 16 also have the same structure as the spacer ring 13.

The top spacer ring 17, the spacer rings 13 to 16 and the grooves 17a, 13a, 13b, ... 6a of the magnetic disk receiving portion 6A are formed to have the same width. In other words, the outer contact portion 6b of the spindle hub 6, the inner contact portion 6c, the outer contact portion 17b of the top spacer ring 17, the inner contact portion 17c, and the outer contact portion 13c of each spacer ring 13-16. , 1
3e ..., the inner contact portions 13d, 13f, ... are formed to have the same cross-sectional shape, and the outer diameters of these outer contact portions are set to the same size, and the inner diameters are set to the same size. The outer diameters of these inner contact portions are set to the same size, and the inner diameters are set to the same size.

The magnetic disks 8 to 12 are attached to the spindle hub 6.
When fixed to the outer peripheral portion of the magnetic disk 8, the magnetic disks 8 to 12 are alternately laminated via the spacer rings 13 to 16 and the top spacer ring 20 is formed on the upper surface of the magnetic disk 8.
By mounting and fixing the clamp ring 20 to the spindle hub 6 with screws 18 and 19 to hold and fix the magnetic disks 8 to 12, the top spacer ring 17 and the spacer rings 13 to 16 to the spindle hub 6. Has become.

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

By fixing the magnetic disks 8 to 12, the top spacer ring 17, and the spacer rings 13 to 16 to the spindle hub 6 of the spindle motor assembly of the magnetic disk device with the screws 18 and 19 via the clamp ring 20. In the assembled state of the magnetic disk assembly, the pressing force generated by the clamp ring 20 is
It is applied to the upper portion of the annular groove portion 17a of the top spacer ring 17 via the annular protrusion portion 20a of the clamp ring 20.

Further, the pressing force applied from the clamp ring 20 to the upper portion of the annular groove portion 17a of the top spacer ring 17 is applied to the annular outer contact portion 17b of the top spacer ring 17 and the annular inner contact portion 17c. And is applied to the outer contact portion 17b and the inner contact portion 17c as equal pressing forces.

Outside contact portion 1 of top spacer ring 17
7b and the inner contact portion 17c are equally applied to the outer contact portions 13c, 1 of the spacer rings 13-16.
3e, inner contact portions 13d, 13f, and the outer contact portion 6b and inner contact portion 6c of the magnetic disk receiving portion 6A of the spindle hub 6, respectively.

That is, the outer contact portion 6b, the inner contact portion 6c, the outer contact portion 17b, and the inner contact portion 17 of the top spacer ring 17 of the magnetic disk receiving portion 6A of the spindle hub 6.
c, and the outer contact portion 13 of each spacer ring 13-16
c, 13e ..., Inner contact portions 13d, 13f ...
Are arranged to face each other via the magnetic disks 8 to 12, the pressing force applied from the clamp ring 20 to the top spacer ring 17 is equal to the spacer rings 13 to 1.
The same force is applied to the outer abutting portion and the inner abutting portion of the magnetic disk receiving portion 6A of the spindle 6 and the spindle hub 6.

Therefore, for the magnetic disks 8-12, the magnetic disks 8-12 and the top spacer ring 1 are used.
7, the spacer rings 13 to 16 and the outer hub contact portion and the inner hub contact portion of the spindle hub 6 are always applied with the same force, so that the magnetic disks 8 to 12 include the clamp ring 20, the top spacer. It is held in a horizontal state by the ring 17, the spacer rings 13 to 16 and the spindle hub 6. As a result, the magnetic disks 8-12
It is possible to prevent the warp and warp from occurring.

As described above, according to this embodiment, the top spacer ring 1 is formed by the protrusion 20a of the clamp ring 20.
The pressing force applied to the annular groove portion 17a of No. 7 is dispersed as a uniform force to the top spacer ring 17, the spacer rings 13 to 16 and the outer and inner contact portions of the magnetic disk receiving portion 6A. Therefore, the magnetic disk 8
As a result, the same force is always applied from the clamp ring 20 to the radially inner portion of the magnetic disks 8 to 12 via the outer contact portion and the inner contact portion, so that the magnetic disks 8 to 12 can be prevented from being deformed. . 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 12 by a magnetic head (not shown). Writing / reading can be performed.

Further, according to the present embodiment, the contact portion (the point of application of the pressing force) of the protruding portion 20a of the clamp ring 20 with the top spacer ring 17 is always located above the groove portion 17a of the top spacer ring 17. Therefore, when the clamp ring 20 is fastened to the spindle hub 6 with the screws 18 and 19, for example, the clamp ring 2
Even if 0 is deformed, the magnetic disks 8 to 1
It is possible to always hold and hold 2 with a uniform pressing force.

Further, according to this embodiment, since the magnetic disks 8 to 12 can be prevented from being deformed as described above, the magnetic head and the magnetic disk 8 are in standby or in seek operation.
As a result of ensuring a predetermined gap between the magnetic head and the magnetic disk, it is possible to prevent a so-called head crash phenomenon in which the magnetic head contacts the disk.

Here, in the present embodiment, as shown in FIG. 5, for example, a contact portion of the clamp ring 20 on the top spacer ring 17 is formed into a V-shaped groove 17d which is annularly continuous along the circumferential direction of the top spacer ring 17. May be formed. Thereby, the protrusion 20 of the clamp ring 20
By engaging a with the groove portion 17d of the top spacer ring 17, the clamp ring 20 can be easily positioned with respect to the top spacer ring 17, so that the work of assembling the clamp ring 20 with the top spacer ring 17 can be performed efficiently. It can be carried out.

[0029]

As described above, according to the magnetic disk device of the present invention, the magnetic disk receiving portion, the spacer members, and the top spacer member are provided with the annular groove portions along the circumferential direction, and the top of the clamp member is provided. Since the annular protrusion is provided at the groove facing portion of the spacer member, the clamp member is always provided to the radially inner portion of each magnetic disk through the annular outer portion and the annular inner portion formed by the respective groove portions. As a result of applying equal force, it is possible to prevent the deformation of the magnetic disk, which causes a so-called modulation phenomenon in which the write waveform and the read waveform are distorted when information is written in or read from the magnetic disk by the magnetic head. Can be prevented, and therefore proper writing /
It can be read. Further, 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 of the magnetic head or seek operation. This has the effect of preventing the crash phenomenon.

Further, in the magnetic disk device of the present invention, when the widths of the top spacer member, each spacer member and each groove portion of the magnetic disk receiving portion are set to the same dimension, the same dimension width formed by each groove portion. Since even more equal force can be applied respectively from the clamp member to the radially inner portion of the magnetic disk through the contact points between the annular outer portion and the inner portion having the same size width, the same as above. This has the effect of preventing deformation of the magnetic disk.

Further, in the magnetic disk device of the present invention, when the vertical cross-sectional shape of the protruding portion of the clamp member is semicircular, the pressing force of the clamp member is applied to the top spacer member through the protruding portion. From this structure, the force applied to the top spacer member from the semicircular protrusion in the vertical cross section of the clamp member is more exerted on the annular outer portion and the annular inner portion formed by the annular groove portion of the top spacer member. It is possible to disperse it as a more even force, and thus it is possible to effectively prevent the deformation of the magnetic disk.

[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 top spacer ring in this embodiment.

FIG. 4 is a vertical cross-sectional view showing the structure of a spacer ring in this embodiment.

FIG. 5 is a vertical cross-sectional view showing a mounting state of a clamp ring and a top spacer ring in a modified example with a part omitted.

FIG. 6 is a vertical cross-sectional view showing configurations of a magnetic disk assembly and a spindle motor assembly of a conventional magnetic disk device.

FIG. 7 is a vertical cross-sectional view showing the structure of a clamp ring in a conventional example.

FIG. 8 is a vertical sectional view showing a structure of a spacer ring in a conventional example.

[Explanation of symbols]

2 spindle shaft 4,5 bearing 6 spindle hub 6A magnetic disk receiving portion 6a groove portion 6b outer contact portion 6c inner contact portion 8, 9, 10, 11, 11, 12 magnetic disk 13, 14, 15, 16 spacer as spacer member Rings 13a, 13b Grooves 13c, 13e Outer abutment 13d, 13f Inner abutment 17 Top spacer ring as a top spacer member 17a Groove 17b Outer abutment 17c Inner abutment 20 Clamp ring 20a as a clamping member Projection

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 provided with a disk-shaped clamping member that holds and holds the magnetic disk in a direction, in a radial center portion of a magnetic disk contact surface of the magnetic disk receiving portion, along a circumferential direction of the magnetic disk receiving portion. An annular groove portion is provided, and an annular groove portion is provided along the circumferential direction of each spacer member at the radial center portion of the magnetic disk contact surface of each spacer member. , An annular top spacer member is interposed between the clamp member and the uppermost magnetic disk, and a radial direction center portion of the magnetic disk contact surface of the top spacer member has a circumferential direction of the top spacer member. A magnetic disk device, characterized in that a groove portion which is connected in an annular shape is provided along a groove, and a protruding portion which is connected in an annular shape is provided along a circumferential direction of the clamp member at a position of the clamp member facing the groove portion of the top spacer member. . 2. The magnetic disk drive according to claim 1, wherein the top spacer member, each spacer member, and each groove portion of the magnetic disk receiving portion are set to have the same width. 3. The magnetic disk drive according to claim 1, wherein the protrusion of the clamp member has a semicircular vertical cross section.