JPS6040582A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To remove the dust attached to a disk by wavign a liner sheet to the case surface and adhering the liner sheet to a case through the top parts of the wave of the liner sheet. CONSTITUTION:Liner sheets 10 and 20 are formed by waving disk-shaped thin unwoven fabric toward its circumference so that top parts 11, 12, 21 and 22 are extended radially. The diameter of the fabric disk is approximately equal to a magnetic disk 1, and the height between top parts 11 (21) of one side and top parts 12 (22) of the other side are approximately equal to the depth of a groove 6.Then the sheets 10 and 20 are put on both sides of the disk 1 with cocontact secured between top parts 12 and 22. The top parts 11 and 21 are adhered to cases 4 and 5 respectively by melt fusion.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of a compact and highly replaceable flexible disk device.

FIG. 1 is an exploded perspective view of a conventional magnetic disk device of this type, in which a flexible magnetic disk 1 is coated with magnetic material such as ferrous oxide on both surfaces, and its magnetic A disc-shaped liner sheet (2.3) made of non-woven fabric having approximately the same dimensions as the disk 1 is arranged, and these liner notes (2, 3) are used to cover the magnetic disk (1' (f)).
The magnetic disk 1 and the liner sheet 2.3'e are housed in two plastic cases 4 and 5 from the outside of the liner sheet 2.3, and the cases 4 and 5 are glued together. A magnetic disk device was constructed using the following. Cases 4 and 5 are liner no. 1-2.
A circular cutout 6 is provided on the inner surface facing the liner sheets 2 and 3 with approximately the same outer diameter as the liner sheets 2 and 3, and a center hole 7 for rotationally driving the magnetic disk 1.
, and holes such as a head window 8 for recording and reproducing information on the magnetic disk l by a magnetic head (not shown).

In this type of magnetic disk device, the center hole 7
Alternatively, even if particles such as airborne dust from the head window 8 etc. adhere to the magnetic disk 1, if the magnetic disk 1 rotates while contacting the liner sheet 2.3 bonded to the case 4.5, the magnetic disc 1
Since the dust on the top can be removed by the liner sheets 2 and 3, high reliability can be maintained without reading errors caused by dust even in a relatively bad environment with a lot of dust.

However, in reality, since the magnetic disk 1 and the liner sheets 2 and 3 are thin, less than 1 mm, the IC, the magnetic disk 1, and the liner sheets 2 and 3 are always in contact with each other, and the rotational torque of the magnetic disk 1 increases due to the contact. It was extremely difficult to control the depth of the cutout 6 in the case 4.degree. That is, if the hollows 6 are made shallower to improve the contact between the magnetic disk 1 and the liner sheets 2 and 3, the rotational torque may increase and the magnetic disk 1 may not rotate. 1 and the liner sheet 2.3 may come into contact with each other, and the dust attached to the magnetic disk may be removed from the liner sheet 2.
, 3 could not be removed, and the reliability of the magnetic disk device would be extremely degraded.

In order to eliminate these drawbacks, the present invention makes the liner sheet corrugated against the case surface so that the magnetic disk and the liner sheet are always in contact with each other and there is no increase in rotational torque due to contact. The drawings will be explained in detail.

Figures 2 and 3 show one embodiment of the present invention.
In the figure, the same components as those of the conventional example are represented by the same reference numerals.

That is, ■ is a magnetic disk, 4, 51d case, 6 is a hollow, ], 0, 20 is a liner sheet. liner sea)], 0.

20 is a disc-shaped thin non-woven fabric with the top 11°12 in the radial direction.
．． 21.22 is corrugated in the circumferential direction so that the diameter is approximately equal to that of the magnetic disk 1, and the case 4.5
The height between one top 11 (21) and the other top 12 (22) extending in the radial direction of the cutout is equal to the depth of the cutout 6. Or (σ is slightly larger.

All of the liner sheets 10.20 are arranged so that their tops 12.22 are in contact with the upper and lower surfaces of the magnetic disk l, and the magnetic Disc l and liner sheet) 10.20 all stored, liner sheet 1
A magnetic disk device is constructed by adhering the top portion 11.21 of the 0°20 angle to the cases 4 and 5 by total heat fusion, etc., and adhering the cases 4 and 5 together.

According to the above Example IC, the liner sheet 10°20
The height between the two apexes is equal to the depth of the comb 6 of the cases 4 and 5, or is slightly cylindrical, so that the apex 12 extends in the radial direction.
22 is in reliable contact with the two surfaces and the bottom surface of the magnetic disk 1, so that the dust adhering to the magnetic disk 1 is completely removed by the top portion 12.22 when the magnetic disk 1 rotates. Become. Also liner sheet 1
0.20 and the magnetic disk 1 only at the top 12.22, the contact area is small, and it is made of a thin non-woven fabric.
Since the top portion 12.22 deforms in the direction of its lower part or the left and right gaps, the rotational torque of the magnetic disk 1 can always be kept small. Furthermore, liner sheet 1
0 and 20 have the same height between the two vertices, so
The magnetic disk 1 can be held in the middle of the case 4.degree. 5, allowing more accurate recording and reproduction.

In addition, this example (disc-shaped liner seam in C) 1
Although the entire surface of the 0.20 has a wavy structure, a part of the liner sea) 10.20, especially the plastic case 4
．． It is also possible to have a structure in which only the vicinity of the head window No. 5 is undulated. Further liner sea) 1.0.20
If the arrangement is such that the vertices 12 and 22 that come into contact with the magnetic disk 1 are placed in plane-symmetrical positions with respect to the magnetic disk 1, the magnetic disk 1 is moved closer to the center of the cases 4 and 5 according to liner sea) 10.20. It can be supported accurately, and the surface of the magnetic disk does not run out when recording and reproducing information using the magnetic head.

As explained above, according to the present invention, the liner sheet and the magnetic disk are always in contact with each other inside the case of the magnetic disk device, so that dust attached to the magnetic disk from the outside can be reliably removed by the liner sheet. Highly reliable FJE k can be maintained without reading errors, there is no increase in rotational torque of the magnetic disk due to contact between the liner sheet and the magnetic disk, and the magnetic disk can be supported in the center of the case. ,
It has the advantage of extremely stable recording and reproduction. Furthermore, the thickness of the case, the depth of the hollowing, etc. need only be moderately accurate, and there is an advantage that a magnetic disk device that is easy to manufacture and inexpensive can be obtained.

[Brief explanation of the drawing]

The drawings are for explaining the present invention, and FIG. 1 is an exploded perspective view of a conventional magnetic disk device, and FIGS. 2 and 3 show an embodiment of the magnetic disk device of the present invention.
The figure is a perspective view of the main part, and FIG. 3 is a sectional view of the main part. 1... Magnetic disk, 4, 5. Plastic case, 6. Hollow out, 10.20... Liner note, 11, 12, 21. 22... Top. Patent Applicant Nippon Telegraph and Telephone Public Corporation Agent Patent Attorney Yoshi 1) Takashi Sei Figure 1 Figure 2

Claims (1)

[Claims] In a magnetic disk device in which a flexible magnetic disk is housed in a flat case, and a liner sheet roller is interposed between the upper and lower surfaces of the magnetic disk and the case, the liner sheet has a wavy structure with respect to the case surface. The liner sheet and the case are bonded together at the part where the wavy top of the liner sheet and the case come into contact, and the liner note and the magnetic disk are brought into contact at the other top parts that do not come into contact with the case. disk device.