JPH08129814A - Magnetic disk device - Google Patents

Abstract

PURPOSE: To prevent a magnetic disk medium etc., from warping by satisfactorily dispersing the clamping force given through a clamp ring. CONSTITUTION: The plural magnetic disk media 15 are arranged in the stacked state at the outer peripheral side of a spindle hub 14. These magnetic disk media 15 are positioned for every specified space through a spacer ring 16, then the magnetic disk media 15 and the spacer ring 16 are fixed while being held between a medium receiving surface 14C of spindle hub 14 and the clamp ring 17. The diameter of a pressurizing part 17B of clamp ring 17 to the spacer ring 16 and the diameter of a pressurizing part 14D formed on the medium receiving surface 14C of spindle hub 14 are arranged mutually to the same, thus, the device is made so that the warp does not occur on the magnetic disk media 15, etc., when the clamping force is given.

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 structure for preventing deformation such as warpage that may occur when a magnetic disk medium is fixedly arranged on a spindle hub.

[0002]

2. Description of the Related Art As shown in FIG. 5, a conventional magnetic disk device is inserted into a case 32 in which a predetermined space is defined by a base 30 and a cover 31, and a hole 30A formed in the base 30. A shaft 33 extending into the case 32, a spindle hub 34 arranged on the outer peripheral side of the shaft 33 to form a motor drive section, and a spindle hub 34 arranged on the outer peripheral side of the spindle hub 34 and recording predetermined information. A plurality of magnetic disk media 35, a spacer ring 36 for performing a predetermined positioning of the plurality of magnetic disk media 35 at a distance from each other along the axial direction of the spindle hub 34, and an upper surface of the uppermost spacer ring 36. Spindle hub 3 via a fastening screw (not shown)
4 is provided.

[0003] The clamp ring 37 is provided in a shape having a flange portion 37A whose cross section has an inverted U-shape. When the above-mentioned fastening screw is screwed in, the inner edge of the flange portion 37A becomes a spacer ring. The spacer ring 36 and the magnetic disk medium 35 are interposed and fixed between the pressing part 37B and the medium receiving surface 34A formed at the lower end of the spindle hub 34. ing.

[0004]

However, in recent years, the magnetic disk devices have been made smaller and lighter, and the thicknesses of the magnetic disk medium 35 and the medium receiving surface of the spindle hub 34 have become thinner and thinner. .

For this reason, the clamping force of the clamp ring 37 causes the magnetic disk medium 35 at the uppermost position,
The medium receiving surface 34A of the spindle hub 34 is easily warped and deformed, and this deformation causes a slight change in the flying height of the magnetic head that moves relative to the magnetic disk medium 35, resulting in read / write defects or head crashes. Therefore, there is a problem that the quality and reliability of the magnetic disk device as a whole are significantly impaired.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is to improve the disadvantages of the prior art, and in particular, it is possible to satisfactorily disperse the tightening force applied via a clamp ring, thereby avoiding warpage of a magnetic disk medium or the like. Accordingly, it is an object of the present invention to provide a magnetic disk drive capable of ensuring a predetermined read / write accuracy.

[0007]

According to the present invention, a spindle hub mounted on the outer periphery of a shaft, a magnetic disk and a spacer ring sequentially stacked on the outer periphery of the spindle hub, and one end of the spindle hub. A clamp ring, which is provided on the spindle hub and has an annular abutment surface for fixing the magnetic disk and the spacer ring to the spindle hub, and which functions at the other end of the spindle hub in cooperation with the clamp ring. In a magnetic disk device having a magnetic disk and a flange portion having a medium receiving surface for holding a spacer ring, the medium receiving surface of the flange portion has substantially the same size as the annular contact surface of the clamp ring. The ring-shaped receiving surface is used. This aims to achieve the above-mentioned object.

[0008]

In the present invention, since the pressing portion diameter of the clamp ring and the pressing portion diameter of the spindle hub are set to be the same, even if a predetermined tightening force is applied,
The balance of tightening force is maintained equally. As a result, no force is generated to warp the spacer ring and the magnetic disk medium fixed between the clamp ring and the medium receiving surface of the spindle hub.

[0009]

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

FIG. 1 is a schematic sectional view of a magnetic disk drive according to this embodiment. In this figure, a magnetic disk drive includes a case 12 in which a predetermined space is defined by a base 10 and a cover 11, a shaft 13 inserted into a hole 10A formed in the base 10 and extending into the case 12, A spindle hub 14 disposed on the outer peripheral side of the shaft 13 to constitute a motor driving unit; a plurality of magnetic disk media 15 disposed on the outer peripheral side of the spindle hub 14 and recording predetermined information; The magnetic disk medium 15 to the spindle hub 14
A spacer ring 16 for performing predetermined positioning at an interval from each other along the axial direction of
6 is provided with a clamp ring 17 fixed to the spindle hub 14 via a fastening screw (not shown) on the upper surface side.

The clamp ring 17 has a flange portion 17A having a reverse U-shaped cross section and an annular contact surface.
It has. The clamp ring 17 receives a deforming force when a tightening screw (not shown) is screwed in to apply a tightening force to the flange portion 17 of the clamp ring 17.
The inner edge of A acts as a pressing portion 17B for the uppermost spacer ring 16.

On the other hand, the lower end side of the spindle hub 14 in the drawing has a flange portion 14A protruding outwardly perpendicular to the axial direction of the spindle hub 14, and a flange portion 14A.
A bent portion 14B formed from the tip of A toward the flange portion 17A of the clamp ring 17 is integrally provided,
The upper surface of the bent portion 14B is formed as a medium receiving surface 14C. The inner edge of the medium receiving surface 17C acts on the lowest magnetic disk medium 15 as a pressing portion 17D when receiving the above-mentioned tightening force.

The pressing portion 17 of the clamp ring 17
B and the diameter of the pressing portion 14D of the annular medium receiving surface 17C of the spindle hub 14 are set to be the same. These diameters are set to be optimal with respect to the diameter and thickness of the magnetic disk medium 15 and the spacer ring 16. In this regard, according to the simulation, generally, the inner cylinder side surface of the spindle hub 14 and the medium receiving surface 14
It became clear that it was almost at the center of the outer diameter of C. And this coincided with the actual measurement.

Here, the clamp ring 1 according to the present invention.
The shape of 7 is not limited to the shape in the above embodiment, and various changes can be made. For example, as shown in FIGS. 2 to 4, the cross-sectional shape of the outer portion may be formed in a trapezoidal shape, a triangular shape, an arc shape, or the like, and the diameter of the pressing portion 17B formed in each of them corresponds to this. Medium receiving surface 14C
The same action and effect can be obtained as long as they match the diameter of the pressing portion 14D.

Further, in the above-mentioned embodiment, the case where a plurality of magnetic disk media 15 are adopted is shown and described, but the present invention is also applicable to a magnetic disk device adopting a single magnetic disk media 15. Applicable.

[0016]

Since the present invention is constructed and operates as described above, the diameter of the pressing portion of the clamp ring and the diameter of the pressing portion formed on the medium receiving surface of the spindle hub are the same. Since it is provided on the magnetic disk medium, the tightening force applied to the magnetic disk medium and the spacer ring via the clamp ring can be well dispersed, thereby effectively avoiding the cause of warpage of the magnetic disk medium and the like. In addition to the above, it is possible to provide an excellent magnetic disk device that has not been available in the related art in which a predetermined read / write accuracy can be ensured satisfactorily and head crashes and the like can be prevented. .

[Brief description of drawings]

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

FIG. 2 is a partial cross-sectional view showing an example of a clamp ring contact surface shown in FIG.

FIG. 3 is a partial cross-sectional view showing a modified example of the clamp ring shown in FIG.

FIG. 4 is a partial cross-sectional view showing another modified example of the clamp ring shown in FIG.

FIG. 5 is a schematic cross-sectional view showing a conventional magnetic disk device.

[Explanation of symbols]

 13 shaft 14 spindle hub 14C medium receiving surface 14D pressing portion 15 magnetic disk medium 16 spacer ring 17 clamp ring 17B pressing portion

Claims (4)

[Claims] 1. A spindle hub mounted on the outer circumference of a shaft, a magnetic disk and a spacer ring sequentially stacked on the outer circumference of the spindle hub, and a spindle hub mounted on one end of the spindle hub. A clamp ring having an annular abutment surface for fixing the magnetic disk and the spacer ring, and a clamp ring provided at the other end of the spindle hub and functioning in cooperation with the clamp ring to hold the magnetic disk and the spacer ring. In a magnetic disk device having a flange portion having a medium receiving surface, the medium receiving surface of the flange portion is an annular receiving surface of substantially the same size corresponding to the annular contact surface of the clamp ring. Characteristic magnetic disk device. 2. The magnetic disk drive according to claim 1, wherein the annular contact surface of the clamp ring has a flat cross section. 3. The magnetic disk drive according to claim 1, wherein the annular contact surface of the clamp ring has a triangular cross-sectional shape with a pointed portion on the contact side. 4. The magnetic disk drive according to claim 1, wherein the annular contact surface of the clamp ring has a cross-sectional shape that is a semi-circular shape that bulges toward the contact side.