JPH0536191A - Magnetic disk - Google Patents

Abstract

(57) [Summary] [Purpose] An object of the present invention is to provide a magnetic disk in which good contact between a magnetic sheet and a magnetic head is guaranteed without pressing the sheet. [Structure] The magnetic sheet 1 is fixed near the center of the metal disk 11 via an adhesive layer 5. A space 12 is provided between the magnetic sheet 1 and the metal disk 11, and a regulating surface 13 is provided near the outer edge of the magnetic sheet 1 so as to be displaced toward the recording surface side of the magnetic sheet 1 with respect to the reference surface 3. [Effect] Good contact between the magnetic sheet and the magnetic head can be guaranteed semipermanently.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk for recording and reproducing information.

[0002]

2. Description of the Related Art FIG. 6 is a sectional perspective view of a conventional magnetic disk. In FIG. 6, 1 is a magnetic sheet, 2 is a center hub, 3 is a reference surface of the center hub 2, 4 is an engagement hole with a spindle motor for rotating the magnetic sheet 1, and 5 is an adhesive layer. The vicinity of the center of the magnetic sheet 1 is fixed to the center hub 2 via an adhesive layer 5. On the other hand, since the outer edge of the magnetic sheet 1 is a free end, the recording surface of the magnetic sheet 1 becomes flat as shown in FIG. 7 due to the action of unavoidable internal stress generated in the manufacturing process of the magnetic sheet 1. In many cases, it is greatly displaced.

FIG. 8 shows an example of a recording / reproducing apparatus using a conventional magnetic disk. 6 is a magnetic head,
Reference numeral 7 is a spindle motor, 8 is a feed screw, 9 is a stepping motor, and 10 is a sheet retainer. The magnetic head 6
By driving the stepping motor 9 and rotating the feed screw 8, the magnetic sheet 1 can be moved to an arbitrary position in the radial direction. The sheet presser 10 is attached to the magnetic sheet 1 as shown in FIG.
The magnetic sheet 1 is pressed toward the magnetic head 6 side in the vicinity of the magnetic head 6 in order to ensure a close contact between the magnetic sheet 1 and the magnetic head 6 even if there is a bending deformation as shown in FIG.

[0004]

However, in the recording / reproducing apparatus using the above-described conventional magnetic disk, the sheet retainer 10 is indispensable, and since the sheet retainer 10 and the magnetic sheet 1 are in contact with each other, the magnetic sheet 1 is damaged. Attached
There is a problem that the sheet presser 10 is worn, the correction force for the magnetic sheet 1 is weakened, and the head touch is deteriorated.

The present invention solves the above-mentioned conventional problems, and provides a novel magnetic disk in which a good contact between a magnetic sheet and a magnetic head is guaranteed without providing a recording / reproducing apparatus with a sheet retainer. To aim.

[0006]

In order to achieve this object, a magnetic disk according to the present invention comprises a magnetic sheet and a hard disk having a rigidity at least higher than that of the magnetic sheet, and the magnetic sheet is provided near the center of the hard disk. The hard disk is provided with a restricting surface that contacts the magnetic sheet, and the hard disk has a recess that does not contact the magnetic sheet, and the restricting surface is the reference surface. On the other hand, the magnetic sheet is displaced toward the recording surface side of the magnetic sheet so as to approach the magnetic head.

[0007]

According to the present invention having the above-mentioned structure, the magnetic sheet is pressed against the magnetic head by contacting the magnetic sheet with the magnetic head in the concave portion provided in the middle portion of the hard disk, and the regulation surface is the magnetic sheet. Corrects flexural deformation. Further, since the regulation surface is closer to the magnetic head with respect to the reference surface, the magnetic sheet is sufficiently pressed against the magnetic head even at the outer peripheral portion of the magnetic sheet, and good recording / reproducing can be realized.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. However, the same components as those of the conventional example are designated by the same reference numerals and the description thereof will be omitted.

(First Embodiment) FIG. 1 is a sectional perspective view of a magnetic disk according to a first embodiment of the present invention. Reference numeral 11 is a metal disk, and the magnetic sheet 1 is fixed to the vicinity of the central portion of the disk through an adhesive layer 5. Reference numeral 12 is a space portion provided between the magnetic sheet 1 and the metal disk 11, and reference numeral 13 is a regulation surface provided near the outer edge of the magnetic sheet 1 and further below the reference surface 3. The bending deformation of the magnetic sheet 1 is
Deflection in the direction away from the metal disk 11 is allowed,
It is restrained by the deflection restricting surface 13 in the direction approaching the metal disk 11. It should be noted that the thinner the adhesive layer 5 is (5 μm or less) as much as possible, the smaller the expansion and contraction due to the change in temperature and humidity, and the wrinkle does not occur in the magnetic disk.

FIG. 2 shows a sectional view of a magnetic disk mounted on a recording / reproducing apparatus. The tip of the magnetic head 6 is positioned so as to enter the space 12. The magnetic sheet 1 has its inner peripheral portion fixed to the reference surface 3 and its outer peripheral portion supported by the regulating surface 13, so that it bends in a chevron shape as shown in FIG. As a result, the magnetic sheet 1 is pressed against the magnetic head 6 by the action of its elastic restoring force. As described above, by using the magnetic disk of the present invention, the contact force between the magnetic sheet 1 and the magnetic head 6 can be obtained even if the recording / reproducing apparatus does not have the sheet retainer 10 as shown in FIG. However, in order to realize good contact, the height relationship among the reference surface 3, the magnetic head 6, and the restriction surface 13 is important.

FIG. 3 is a view for explaining the height relationship among the reference surface 3, the magnetic head 6 and the restriction surface 13. The magnetic head 6 is located above the reference plane 3 by a distance DH, and
3 is configured to be located below the reference plane 3 by a distance DS. For example, when a magnetic sheet having a thickness of 40 μm and a diameter of 47 mm is used, both DH and DS are 50 to 100 μm.
Is appropriate.

By doing so, the magnetic head 6
The deformation of the magnetic disk in the vicinity becomes substantially symmetrical with respect to the magnetic head 6, and good contact can be obtained. Metal disk 11
Since it rotates integrally with the magnetic sheet 1, there is no possibility that the regulation surface 13 will be worn or the magnetic sheet 1 will be damaged by the regulation surface 13.

(Embodiment 2) FIG. 4 is a sectional view of a magnetic disk according to a second embodiment of the present invention. The magnetic disk according to the first embodiment has a reference surface 3, an engagement hole 4, and a space 1.
2, the regulation surface 13 is integrally formed of the same metal body,
As shown in FIG. 4, the center member 14, the disk member 15, and the protruding member 16 may be divided into three members to achieve the object of the present invention. Therefore, the optimum combination of members can be selected according to the purpose of use of the magnetic disk and the environment.

(Embodiment 3) FIG. 5 is a sectional view of a magnetic disk according to a third embodiment of the present invention. Magnetic sheet 1,
Since the reference surface 3, the space portion 12, and the regulation surface 13 are arranged on both sides of the metal disk 11, the recording capacity of one magnetic disk can be double that of the first embodiment.

[0015]

As is apparent from the above embodiments, according to the present invention, the magnetic sheet is fixed to the reference surface provided near the center of the hard disk, and the outer periphery of the hard disk is in contact with the magnetic sheet. The surface of the hard disk is provided with a concave portion that does not contact the magnetic sheet, and the regulation surface is configured to approach the magnetic head with respect to the reference surface. It is possible to provide a magnetic disk capable of guaranteeing stable permanent contact.

[Brief description of drawings]

FIG. 1 is a sectional perspective view of a magnetic disk according to a first embodiment of the present invention.

FIG. 2 is a sectional view when the magnetic disk of the same embodiment is mounted on a recording / reproducing apparatus.

FIG. 3 is a diagram for explaining the main dimensions of the magnetic disk of the embodiment.

FIG. 4 is a sectional view of a magnetic disk according to a second embodiment of the present invention.

FIG. 5 is a sectional view of a magnetic disk according to a third embodiment of the invention.

FIG. 6 is a sectional perspective view of a conventional magnetic disk.

FIG. 7 is a cross-sectional perspective view for explaining flexural deformation of the magnetic disk of the conventional example.

FIG. 8 is a sectional view when the magnetic disk of the conventional example is mounted on a recording / reproducing apparatus.

[Explanation of symbols]

 1 Magnetic Sheet 3 Reference Surface 11 Metal Disk 12 Space 13 Regulation Surface

Claims (1)

Claim: What is claimed is: 1. A magnetic sheet, and a hard disk having rigidity at least higher than that of the magnetic sheet. The magnetic sheet is fixed to a reference surface provided near the center of the hard disk.
An outer peripheral portion of the hard disk is provided with a restricting surface in contact with the magnetic sheet, a concave portion not in contact with the magnetic sheet is provided in the middle peripheral part of the hard disk, and the restricting surface is relative to the reference surface. A magnetic disk constructed by displacing to the recording surface side of the magnetic sheet.