JPH0115037Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a floppy disk cassette equipped with a lifter for pressing a liner sheet for cleaning the recording surface of the floppy disk onto the floppy disk.

[Background technology and its problems]

The floppy disk cassette prevents the drop-out phenomenon in which the recorded signal cannot be partially recorded or reproduced due to dust getting between the stored floppy disk and the magnetic head of the recording/reproducing device, or due to the floppy disk being charged. Therefore, a liner sheet made of nonwoven fabric or the like is provided to clean the floppy disk. In order to ensure the cleaning effect of this liner sheet, a lifter is provided to press the liner sheet against the floppy disk.

FIG. 1 is an exploded perspective view of such a conventional floppy disk cassette. 1 is a floppy disk (hereinafter referred to as "a floppy disk") in which a recording surface made of a magnetic layer is formed at least on the lower side of a thin disc-shaped polymer film.
It's simply called a disk. ), 2 is a center plate attached to the center of the disk 1 with a double-sided adhesive tape 3, 4 is an upper liner sheet disposed above the disk 1, and is provided with an elongated hole 5. Reference numeral 6 denotes a lower liner sheet disposed below the disk 1, which has an elongated hole 7 at a position facing the elongated hole 5.
is provided.

8 is an upper half, with a long hole 9 at a position facing the long holes 5 and 7, and a recess 10 on the outer surface including the long hole 9.
However, a group of protrusions 11 (see FIGS. 2 a and b) that are uniform in height in the radial and circumferential directions of the disk 1 are provided at predetermined positions on the inner surface, and the upper liner sheet 4 is partially welded. and installed. 12
is the lower half, with a long hole 14 at a position facing the long holes 5, 7, and 9, and a recess 1 on the outer surface including this long hole 14.
A concave portion 15 is provided at a position facing 0, a protrusion 16 is uniform in height in the radial direction of the disk 1, and a protrusion 16 is uniform in height in the circumferential direction of the disk 1 at a predetermined position on the inner surface facing the protrusion group 11. A protrusion 17 is provided, and
A portion of the lower liner sheet 6 is welded and attached.

18 is a lifter made of synthetic resin or metal,
Consisting of a mounting part 18A and a pressing part 18B, the mounting part 18A is attached to the lower half 12, and the pressing part 1
8B is a square.

A shutter 19 is slidably attached to the recesses 10 and 15 of the cassette case consisting of the upper and lower halves 8 and 12, and when the shutter is slid to a predetermined position in the opening direction, the shutter opens into the elongated holes 5, 7, 9, 14. Elongated holes 20 and 21 are provided that overlap with the.

When the floppy disk cassette with the above configuration is assembled and the lifter 18 is shown, the cross-sectional view in the circumferential direction of the disk 1 is shown in FIG. 2a, and the cross-sectional view in the radial direction of the disk 1 is shown in FIG. 2b. . As can be seen from these figures, the pressing portion 18B of the lifter 18 presses the lower liner sheet 6 against the disk 1 by its elastic force, and the disk 1 is in a state of being cleaned. Therefore, it is possible to prevent the dropout phenomenon from occurring. In addition, there is a group of protrusions 1 on the upper and lower halves 8 and 12.
1 and the protrusions 16 and 17 are provided to ensure that the lower liner sheet 6 is pressed against the disk 1 and to prevent the lifter 18 from coming into close contact with the lower half 12.

However, if the upper half 8 protrudes outward or deforms due to loading the floppy disk cassette into the recording/reproducing device and chucking the disk 1, or due to changes over time, the lower half 1
2 is protruded or deformed, and if the lower half 12 is made to protrude outward in a spherical shape to ensure clearance for the portion of the upper and lower halves 8 and 12 that accommodates the disk 1, the disk In the circumferential and radial direction of 1, the cross-sectional views are shown in Figure 3 a and b,
The pressing force of the lifter 18 that presses the lower liner sheet 6 toward the inner periphery of the disk 1 becomes weaker. Therefore, there is a problem that the inner periphery of the disk 1 cannot be cleaned sufficiently and a dropout phenomenon occurs.

[Purpose of invention]

This invention was devised in view of the above-mentioned problems, and aims to provide a floppy disk cassette that allows the inner periphery of the disk to be sufficiently cleaned even when the cassette case is deformed.

[Summary of the idea]

In order to achieve the above-mentioned purpose, this idea is to provide a member on the upper half opposite to the lifter, which increases in height toward the inner periphery of the disk, so that even when the cassette case is deformed, the inner periphery of the disk can be maintained. This allows for thorough cleaning.

〔Example〕

FIG. 4 is a partial sectional view of a group of protrusions taken by cutting the upper half in the radial direction of the disk, showing an embodiment of this invention, where 8 is the upper half, and 22 is a position facing the lifter on the inner surface of the upper half 8. The height increases from the outer circumference to the inner circumference of the disk, and the height is uniform in the circumferential direction of the disk.

As shown in FIG. 4, when the upper half 8 is provided with a group of protrusions 22 which become higher toward the inner circumference of the disk, the clearance with the lower half becomes smaller toward the inner circumference of the disk. This means that the clearance between the group of protrusions 22 and the lifter becomes smaller toward the inner circumference of the disk, and the pressing force of the lifter becomes larger toward the inner circumference of the disk. Therefore, even if the cassette case is deformed as shown in FIG. 3, the circumference and radial direction of the disk 1 will be the cross-sectional views shown in FIGS. 6 can be uniformly pressed by the pressing portion 18B of the lifter 18. That is, the inner periphery of the disk 1 can be sufficiently cleaned, and the dropout phenomenon will not occur.

FIG. 6 is a partial cross-sectional view of the pressing member of another embodiment of the invention, taken by cutting the upper half in the radial direction of the disk, where 8 is the upper half, and 23 is a position facing the lifter on the inner surface of the upper half 8. It is a pressing member attached to the lifter, has a predetermined area facing the lifter, is made of an elastic material such as nonwoven fabric, rubber, etc., and is made higher than the height of the protrusion group 11 shown in FIGS. 2a and 2b.

If the pressing member 23 made of an elastic body is attached as shown in FIG. 6, even if the pressing force of the lifter 18 becomes weak, such as when the cassette case is deformed as shown in FIG. As shown in the figure, the lower liner sheet 6 can be uniformly pressed onto the inner and outer peripheries of the disk 1 by the pressing portion 18B of the lifter 18. Therefore, the inner periphery of the disk 1 can be sufficiently cleaned and the dropout phenomenon will not occur.

In the above embodiment, the height of the protrusion group 22 increases from the outer circumference to the inner circumference of the disk 1, and is uniform in the circumferential direction of the disk 1. A plurality of strips may be provided in the radial direction of the disk 1.

[Effect of idea]

As explained in detail above, in the floppy disk cassette of this invention, a member that becomes higher toward the inner circumference of the disk is provided on the upper half facing the lifter, so that even if the cassette case is deformed, the disk will remain stable. The inner periphery of the can be thoroughly cleaned. Therefore, there is an advantage that the dropout phenomenon does not occur.

[Brief explanation of the drawing]

Figure 1 is an exploded perspective view of a conventional floppy disk cassette, Figures 2 and 3 are partial sectional views of the lifter, each figure a shows a circumferential cross section of the floppy disk, and each figure b shows a cross section of the floppy disk in the circumferential direction. Figure 3 shows a radial cross section of the floppy disk. Fig. 4 is a partial sectional view of a group of protrusions taken by cutting the upper half in the radial direction of the disk, showing an embodiment of this invention, and Fig. 5 a and b show the circumference and radial direction of the floppy disk in the lifter section. FIG. 6 is a partial sectional view of a pressing member in another embodiment of the invention, with the upper half cut in the radial direction of the disk. In the figure, 1 is a floppy disk, 4 is an upper liner sheet, 6 is a lower liner sheet, 8 is an upper half, 12 is a lower half, 18 is a lifter, 2
2 is a group of protrusions, and 23 is a pressing member.

Claims (1)

[Scope of utility model registration request] A floppy disk cassette in which a floppy disk and a liner sheet are housed in a cassette case consisting of an upper half and a lower half, and a lifter for pressing the liner sheet onto the floppy disk is attached to the lower half, A floppy disk cassette characterized in that a member that increases in height toward the inner periphery of the floppy disk is provided on the upper half so as to face the lifter.