JPH01105372A - Magnetic disk housing case - Google Patents

Abstract

PURPOSE:To improve cleaning ability with a liner and to improve recording/ reproducing characteristics by arranging the liner, which is slidingly connected to a disk, at the internal side of a case main body to house the magnetic disk. CONSTITUTION:A magnetic disk cartridge 1 is separated to an upper half 2 and a lower half 3, apertures 7 and 8 are formed for the respective halves 2 and 3, and the cartridge 1 is constituted so as to face the magnetic disk 10. At the internal surface of the respective halves 2 and 3 of the cartridge 1, approximately C-shaped lines 4 and 5 for disk cleaning are arranged. Peripheral parts 4a, 4b, 5a and 5b are joined and fixed by a thermal deposit or a supersonic welding while the both liners 4 and 5 are made into a slightly slack condition. Further, a sliding area to the disk 10 is increased with the slackness of the liners 4 and 5, the disk 10 is sufficiently cleaned, and a residual foreign material and a dropout because of the attachment of the head 19 due to the foreign material, etc., are prevented from generating.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a magnetic disk storage case, for example 3.5
This relates to inch floppy disk cartridges.

BACKGROUND OF THE INVENTION Conventionally, for example, in a 3.5-inch floppy disk cartridge, a disk cleaning member called a liner is disposed on the inner surface of a half, which is the case body. This liner is typically a non-woven fabric (e.g. rayon braided with thermoplastic polypropylene).
The peripheral side portion is joined to the inner surface of each half by thermal welding or ultrasonic welding. At that time, the liner is punched out so that it has the same area as the liner attachment part of the half.

Therefore, since the conventional liner is tightly joined to the half, the part that contacts the media (magnetic disk) is near the beam lid on the lower half side, and near the beam lid on the upper half side.
It was limited to the vicinity of the ribs, and the cleaning performance was not high. As a result, the head bites into the remaining foreign matter, resulting in dropout.

OBJECTS OF THE INVENTION An object of the present invention is to provide a magnetic disk storage case with improved cleaning performance using a liner and improved recording/reproducing characteristics.

20 Structure of the Invention That is, the present invention provides a magnetic disk storage case in which a liner that is in sliding contact with the magnetic disk is disposed inside a case body that stores a magnetic disk, in which the liner is loosened. This relates to a magnetic disk storage case characterized by being attached to the case body.

E, Example The present invention will be explained in detail below.

1 to 3 show a 3.5 inch floppy disk cartridge 1 according to this embodiment.

Figure 2 shows the inner surfaces of the upper half 2 and lower half 3 of the cartridge 1 after being separated. Each half is formed with an open lower part 8, and the internal floppy disk 10 is configured to face the open lower part 8. The open lower 8 is normally shielded by a metal shutter (not shown) with a U-shaped cross section when the disk is not in use, and the disk 10 (media) is not exposed, but when the disk is not in use, the disk 10 (media) is not exposed. (When recording magnetically)
The shutter is moved to the open position, and the recording surface of the disk 10 is exposed to the open lower part 8. The disk 10 is rotatably housed in the main body half 2.3 while being fixed to a center hub 8 attached to a spindle on the driver side.

What is important about this cartridge 1 is that the approximately C-shaped liner 4.5 (indicated by diagonal lines in Figure 1) for disk cleaning attached to the inner surface of each half is fundamentally different from conventional ones. different, its peripheral edge 4a in a somewhat slack state,
4b, 5a, and 5b are bonded and fixed to the inner surface of each half by heat welding or ultrasonic welding.

Therefore, since the liner 4.5 (especially the liner 4) is loose, as shown in Figs. 2 and 3, when driving a disk (-
A dashed dotted line 9 indicates a magnetic head. ), the liner 5, disk 10, and liner 4 are fixed to the lower half 3 and pressed by the lid 11 against the upper half 2 side rail 7 and 12 at the lifter position, and the sliding contact between the disk and the liner there (i.e., cleaning) Not only is this good, but the liner (particularly 4) comes into sliding contact with the disk 10 over a relatively wide range at other locations as well. Note that the lip 12 is composed of a group of linear projections arranged in a row in the radial direction. Further, one end 11a of the lifter 11 is adhesively fixed to the half 3, and the other end is bent diagonally upward to become a free end. disk 10
The rotation direction of the lower half 30 in FIG. 1 is clockwise.

As described above, since the sliding contact area with the disk 10 increases due to the loosening of the liner, cleaning of the disk can be performed on the 13th bone. Therefore, good recording/reproduction is possible without causing dropouts or the like due to the above-described foreign matter remaining and adhering to the head.

FIG. 4 shows the area where the liner 4 or 5 (particularly 4) is in contact with the media during actual driving. This evaluation is performed experimentally as follows.

First, insert the disk into the drive, and use a dropper to apply 10 mj of diluted magnetic coating liquid on the disk evenly in the radial direction! Drip. After dropping, rotate the disk for 1 minute, remove the disk, and disassemble the outer case (half). If you look at the liner, you can see that the part that was in contact with the disc is colored blue. The cleaning performance was evaluated based on the area ratio of the colored portion 13. Note that the colored portions 13 are often seen particularly at the positions of the lid 11 or the ribs 12 mentioned above.

In addition, in order to loosen the liner as described above, as shown in FIG. Either process the liner to make it longer, or make the width larger in the radial direction as shown by the two-dot chain line 15, and then join the peripheral part of each liner at a predetermined position (this is the same as before). do. However, if it is loosened too much, the sliding contact area will increase too much and the rotational torque of the disk will increase. Therefore, it is better to determine the amount of slack appropriately.

Next, the present invention will be explained in more detail using specific examples.

The liner should be made longer in the circumferential direction than the liner pasting part of the outer case (half) (as shown in 14 in Fig. 4), and the area is 0%, 1%, 2%, 3%, respectively. It was punched out to a size of 4%, and its peripheral side was joined to the outer case by heat welding so that it did not protrude from the liner attachment area. The liner is a nonwoven fabric (for example, Kendall #3 (j
3) was used.

FIG. 5 shows the relationship between disks manufactured under each condition and torque. The torque was measured one month after molding.

Here, running torque (N-cm) is usually 0.25
It is desirable that the thickness is N-cm or less.

As can be seen from FIG. 5, if the area is 3% or more larger than the liner attachment portion, the running torque tends to increase.

Next, FIG. 6 shows the relationship between the disks manufactured under each condition and the cleaning performance described above (the same applies hereinafter). Cleanability is indicated by the percentage of the colored portion (area ratio) in the total area. As shown in the figure, when the area is 1% or more larger than the liner attachment part, the cleaning performance is considerably improved.

From the results shown in FIGS. 5 and 6, it can be seen that increasing the area of the liner by 1% to 2% provides better cleaning performance and requires less torque.

Insert the liner approximately C from the liner pasting part of the outer case.
The width of the shape is increased as shown in 15 in Figure 4, and the area is punched out so that it increases by 0%, 1%, 2%, 3%, and 4%, respectively, and the liner is attached to the surrounding area. The outer case surface was joined by heat welding to prevent it from protruding from the outside. Kendall #303 liner was used. The results of similar tests are shown in FIGS. 7 and 8.

From this result, it can be seen that when the area is increased by 2 to 3%, the cleaning performance is better and the torque is also reduced.

The width of the C-shaped liner and the circumferential length of the liner are made longer than the liner pasting part of the outer case, and the area is 0% for each.
, 1%, 2%, 3%, and 4%, and the peripheral side part was joined to the outer case by heat welding so that it did not protrude from the liner attachment part. Kendall #303 was used as the liner. The results of similar tests are shown in FIGS. 9 and 10.

From this result, it can be seen that when the area is increased by 2 to 3%, the cleaning performance is better and the torque is also reduced.

Incidentally, even when the same tests as in Examples 1 to 3 were conducted using ultrasonic welding when joining the peripheral side portion to the exterior case, similar results were obtained.

↓ Next, we placed fine powder on the disc, put it in a drive for one minute, and spun it to see if it would drop out. Regarding dropouts, the evaluation was based on the number of dropouts of 45% or less. The results are shown in Figure 11, and it can be seen that increasing the liner area (however, increasing the length in the circumferential direction) actually improves cleaning performance and reduces the probability of dropouts occurring. Recognize.

FIG. 12 shows another embodiment of the invention.

In this example, the lower half 3 side will be described (the upper half 2 side may also be treated in the same way, so it is omitted from illustration).
Fix by ultrasonic welding, etc.

At this time, the other end 5d of the liner 5 is located at the position indicated by the dashed line. Next, the other end 5d is moved to the solid line position, and 5a5b is also fixed to the half 3 at the same time using ultrasonic waves or the like. As a result, it is possible to form an appropriate slack in the liner 5 as described above.

FIGS. 13 and 14 show other embodiments of the present invention.

In this example, welded portions 13, 14, and 15 for the halves of the liner 4 or 5 are formed in the radial direction by ultrasonic welding or the like, but during this welding, the liner is preliminarily slackened 16 between the welded portions 13 and 14. Perform welding while leaning.

The welding parts 13, 14, 15 may be entirely welded, or
It may be partially welded.

In this way, the cleaning effect of the liner becomes remarkable due to the slack 16, so it is possible to improve the performance of the - layer, and even if the lid 11 is omitted, the same effect can be achieved by providing the slack 16 at the same position. Cleaning performance is obtained. In this case, the liner may have a structure of two or more layers having different physical properties.

FIG. 15 is similar to FIG. 14, but with the slack 16
This is an example in which the shape of the liner 4 or 5 is changed, and a crease 17 is formed on a part of the liner 4 or 5, and the liner is partially folded back at this point to improve cleaning performance. However, in this case, it is preferable that the disk traveling direction be the A-+8 direction in the drawing.

For example, as shown in the example of FIG. 16, the original shape of the liner 5 (the liner 4 may also be made in the same manner) is made into a complete ring shape at the manufacturing stage, and this ring-shaped sheet
After cutting at position 7, it is welded and fixed at the solid line position in the same manner as in the above example. Therefore, since the liner end portions are moved closer to each other and welded from the position indicated by the two-dot chain line to the position indicated by the solid line, the same slack as described above can be formed. Further, in the welding process according to this example, the liner itself needs only to be prepared in a simple ring shape, cut and welded, so the efficiency of utilization of the nonwoven fabric used for the liner is increased, and it is advantageous in terms of cost. Moreover, manufacturing becomes easy.

FIGS. 17 and 18 show still another embodiment of the present invention.

In this example, the liner 4 or 5 has a heat-shrinkable film (for example, a shrink material such as polypropylene) 2 on the back side of the original liner material 20 as shown in FIG. 17 before loading the cartridge.
1 is laminated. Then, such a liner is made in advance in a large size, and then heated by an appropriate method (for example, surface heating with a heater) to shrink the film 21 as shown in FIG. 18. As a result, the liner material 20 also changes shape and wrinkles, that is, loosens 2.
2 occurs. Therefore, when this is installed on the half as shown in the figure, it makes good contact with the slack parts and improves cleaning performance, and at the same time, the liner itself is reinforced with the film 21, making it strong and preventing it from sagging. .

Although the present invention has been illustrated above, the above-mentioned example can be further modified based on the technical idea of the present invention. 1. For example, the liner to be loosened may be only the liner 4 on the upper half 2 side, and the shape and material of the liner itself may be other than those described above. Further, the shape, structure, and various parts of the outer case (half) can be changed in various ways, such as the rib pattern, the shape and material of the lid, etc. If a rib (not shown in the above example) is also provided on the lower surface of the lifter,
This rib urges the lifter upward (particularly when the lifter is about to be pressed against the lower half surface), and is desirable in that it promotes or assists this effect. Note that the size, type, etc. of cases to which the present invention is applied are not limited to those described above.

(1) Functions and Effects of the Invention As described above, in the present invention, the liner is installed with the liner loosened, so that the slack increases the sliding contact area with the disk.
The disk can be cleaned more than adequately.

Therefore, due to the remaining foreign matter and its attachment to the head,
Dropouts are less likely to occur and good recording/reproduction is possible.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a plan view of the inner surface of the upper and lower halves (exterior case) shown separated, and Fig. 2 is a magnetic disk with both halves joined. Figure 1 is a sectional view taken along the line ■-■ when the
Figure I [1-III sectional view; Figure 4 is a plan view of the liner to explain liner slack and day-screen cleaning effects; Figures 5, 6, 7, 8, and Figure 9, 1st
Figures 0 and 11 are graphs showing performance results for increased liner area, Figures 12, 13, and 14 (X IV in Figure 13).
-XIV line sectional view), 15M, 16, 17,
FIG. 18 is a plan view or a sectional view of main parts according to other embodiments. In addition, in the symbols shown in the drawings, 1......Magnetic disk cartridge 2...
...... Upper half 3... Lower half 4.5... Liners 4a, 4b, 5a, 5b... Joint part (peripheral part) 9... Head 10... Magnetic disk 11... Lifter 12... Rib 13... is a colored portion.

Claims (1)

[Claims] 1. A magnetic disk storage case in which a liner that comes into sliding contact with the magnetic disk is arranged inside a case body housing a magnetic disk, characterized in that the liner is attached to the case body in a slack state. A magnetic disk storage case.