JPH02193378A - Disk cartridge - Google Patents

Abstract

PURPOSE:To uniformize the cleaning effect by forming a lifter having a moving part turned around a stationary part fixed to a disk holding face and having a moving part pressing a liner onto a disk through a folded part. CONSTITUTION:When a force from a liner 5a is exerted to a 2nd moving part 49 of a lifter 41, the moving part 49 is sufficiently deflected, and then a 1st moving part 47 and a folded part 45 are floated from a disk support face 13 of an upper case 11 accordingly. Thus, the liner 5a is depressed even at one end of the moving part 47 and the folded part 45 is floated from the support face 13 and close to the liner 5a, then the liner 5a is pressed onto a magnetic disk 3 with a wide area to disperse the pressing force, thereby obtaining a high cleaning effect with a wide area.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a disk cartridge rotatably housing a magnetic disk for recording information.

(Prior Art) As a magnetic disk for recording information, for example, a disk cartridge, which rotatably houses a flexible magnetic disk, is currently used in personal word processors, personal computers, etc. due to its ease of handling. It is used for.

For example, in a 3.5-inch disk cartridge, a flexible magnetic disk is rotatably housed in the disk holding surfaces of a pair of upper and lower cases molded from ABS resin. A liner made of nonwoven fabric is welded to the disk holding surfaces of the pair of upper and lower cases to prevent the magnetic disk from coming into direct contact with the case and to clean the surface of the magnetic disk. One side of a lifter formed by bending PET film or the like is fixed to the magnetic disk holding surface of one case in order to press the aforementioned liner onto the magnetic disk, and the other side of the magnetic disk holding surface of the other case is fixed to the magnetic disk holding surface of the other case. A raised convex portion is formed to improve the pressing effect of the lifter.

(Problem to be Solved by the Invention) The lifter for the disc cartridge described above forms a movable part through a fixed part fixed to the disc holding surface of the case and a bent part bent at one end of the fixed part. , the movable portion presses the liner due to the restoring force of the bent portion. The liner pressed against the magnetic disk by the lifter removes foreign matter such as dust on the magnetic disk, making the surface of the magnetic disk good.

However, the magnetic disk has some waviness due to various causes, and this waviness causes a large difference in the pressing force of the lifter. In areas with high undulations, the pressing force of the lifter is large and the cleaning effect is high, but in areas with low undulations, the pressing force of the lifter is small and a sufficient leaning effect cannot be obtained.

Further, changes in the pressing force of the lifter also cause variations in rotational torque, which adversely affects recording or reproduction on the magnetic disk.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a disk cartridge that can obtain a uniform leaning effect and perform good recording and reproduction with stable rotational torque by minimizing the amount of change in the pressing force of the lifter. .

[Structure of the Invention] (Means for Solving the Problems) A disk cartridge of the present invention has a magnetic disk for recording information and a disk holding surface for holding the magnetic disk, and rotatably accommodates the magnetic disk. a pair of cases, a liner for cleaning the magnetic disk installed on the disk holding surfaces of the pair of cases, and a lifter installed on at least one disk holding surface of the pair of cases so as to press the liner against the magnetic disk. In the disc cartridge equipped with the above, the lifter has a fixed part fixed to the disc holding surface of the case, a first movable part that is movable about the fixed part, and a direction from the first movable part in the direction of the fixed part. The second movable part presses the liner toward the magnetic disk through the bent part that is bent so as to extend to the magnetic disk.

(Function) Through various experiments, the present inventors discovered that there is the following relationship between the structure of the lifter and the pressing force of the lifter.

W constant number Let the amount of deflection of the suppressing portion of the lifter be (S), and the elastic modulus of the lifter be (E).

Figure 5 shows the relationship between the length (1) of the lifter's suppressing surface and the pressing force (W) of the lifter. ) can be seen to be dispersed and become smaller. Fig. 6 shows the relationship between the lifter deflection m (s) and the lifter pressing force (W), and the lifter pressing force (W) is determined by the lifter deflection f
it (s), and the length of the suppressing surface of the lifter (
It can be seen that as 1) becomes longer, the pressing force (W) of the lifter becomes more stable with respect to fluctuations in the deflection ff1 (s).

The deflection m (s) of the lifter is determined by the waviness of the magnetic disk, and the elastic modulus (E) is determined by the quality of the material used for the lifter.

In order to stabilize the pressing force (W) under such circumstances, it is conceivable to keep the amount of change in the pressing force (W) low by increasing the length (1) of the lifter.

However, it is not possible to make major design changes such as increasing the length (1) of the lifter within a given case.

Therefore, the present inventors designed the lifter to have a unique structure having at least two movable parts as described above, so that the lifter is stored in a predetermined case and the actual length of the lifter is the same as that of the first movable part and the second movable part. It has been found that it can be made equivalent to the sum of the moving parts of . This effectively increases the length of the lifter (
1), the amount of change in pressing force (W) can be made much smaller than in the past.

(First Embodiment) A disk cartridge according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic perspective view of the disk cartridge of this embodiment, and this disk cartridge (1) has a pair of upper and lower cases (I l), (21
) A flexible magnetic disk for recording information is rotatably housed in the disk, and is normally sealed with a shutter (31) to prevent dust from entering the magnetic disk (3) from the outside. .

FIG. 2 shows a schematic cross-sectional view of this disk cartridge (1), which has the following configuration. There is a lifter (41) on the disk holding surface (23) of the lower case (21).
is welded to the lower case (21), and the peripheral portion of the liner (5a) is fixed to the lower case (21) with the lifter (41) in between. Also, the disk holding surface (13) of the upper case (11)
A convex portion (15) is formed at a position facing the lifter (41), and the liner (5) is placed across the convex portion (15).
The peripheral part of b) is welded to the upper case ([1).

A magnetic disk (3) is rotatably housed between the upper case (11) and the lower case (21). Therefore, the dust on the surface of the magnetic disk (3) is removed by the liners (5a) and (5b) every time the magnetic disk (3) rotates.

Next, the structure of the lifter (41) will be explained with reference to FIG. This lifter (41) is integrally formed of SUS, and includes a fixed part (43), a first movable part (47),
It consists of a bending part (47) and a second movable part (49). This fixing portion (43) is firmly fixed to the disk holding surface (23) of the lower case (21), and furthermore, this fixing portion (
A first movable part (47) is formed integrally with the movable part (43). Therefore, the first movable part (47) moves the fixed part (43) -
The ends are movable. A bent part (47) is formed by bending a part of the first movable part (47), and the second movable part (47) is formed by bending a part of the first movable part (47).
9) is formed.

The operation of the disk cartridge (1) having such a configuration will be explained with reference to FIG. FIG. 4(a) shows a state in which no force from the liner (5a) is applied to the second movable portion 49) of the lifter (41).

When force from the liner (5a) is applied to the second movable part (49) of the lifter (41), the second movable part (49) of the lifter (41) is sufficiently deflected, and along with this deflection, The first movable part (47) and the bending part (47) are connected to the upper case (1
1) floats up from the disk holding surface (13).

Therefore, one end of the first movable part also presses the liner (5a), and the bent part (47) also presses against the disk holding surface (13).
Since the liner (5a) floats up from above and approaches the liner (5a), it becomes possible to press the liner (5a) against the magnetic disk (3) over a wide area.

In this way, in the disk cartridge (1) of this embodiment, since the liner (5a) is pressed against the magnetic disk (3) over a wide area, the pressing force that was concentrated locally in the conventional SUS lifter is dispersed and pressed over a wide area. A high Kooning effect can be obtained.

Further, the length of the lifter (41) of this embodiment is equivalent to a lifter having a length equal to the sum of the first movable part (47) and the second movable part (49). Therefore, fluctuations in the pressing force are much smaller than in the past, and a stable cleaning effect can be obtained. Accordingly, it becomes possible to stabilize the rotational torque, and the disk cartridge (1) can perform good recording and reproduction.

Here, we have shown the one for SUS split lifter, but P
A lifter made of ET film may also be used.

(Second Embodiment) A disk cartridge according to a second embodiment of the present invention will be described with the same reference numerals assigned to the same parts as in the first embodiment.

FIG. 7 shows a disk cartridge (
1) is a schematic perspective view of the lifter (41) of the lower case (21), similar to the first embodiment.
It is installed in

This lifter (41) is integrally formed from PET film, and is made by bending a plate-shaped PET film near the center. This bent one side forms a fixed part (43) and a first movable part (47) that are welded to the disk holding surface (23) of the lower case (21),
The other bent side connects the liner (5a) to the magnetic disk (
3) forms a second movable part that presses toward.

By doing so, the liner (5a) comes into contact with the magnetic disk (3) over a wide area as in the first embodiment, so that a sufficient leaning effect can be obtained. Furthermore, since the actual length of the lifter (41) can be increased, fluctuations in the pressing force are small, stable rotational torque can be obtained, and the disk cartridge (1) can perform good recording and playback.
).

Further, it is easy to configure the lifter (4I) as described above, and there is no increase in the number of man-hours or cost compared to the conventional method.

Here, a lifter made of PET film was used, but SU
It is also possible to use a lifter made by S. By using a lifter made of SUS, the elastic modulus changes less over time than a lifter made of PET film, and a stable cleaning effect can be obtained over a long period of time.

[Effects of the Invention] As described in detail above, the disk cartridge of the present invention shows little decrease in the pressing force of the lifter even after long-term use, and a stable pressing force is obtained, so that a sufficient leaning effect can be obtained. .

[Brief explanation of the drawing]

1 is a schematic perspective view of a disk cartridge according to a first embodiment of the present invention, FIG. 2 is a schematic sectional view of the disk cartridge of FIG. 1, and FIG. 3 is a schematic perspective view of a disk cartridge of the first embodiment. 4 is a schematic sectional view showing the operation of the lifter of the disk cartridge according to the first embodiment; FIG. 5 is a graph showing the relationship between the lifter pressing force and the length of the lifter suppressing surface; FIG. FIG. 6 is a graph showing the relationship between lifter pressing force and lifter deflection amount, and FIG. 7 is a schematic perspective view of a lifter related to a disk cartridge according to a second embodiment of the present invention. (1) Disk cartridge (3) Magnetic disk (5a) Liner (5b) Liner (11) Upper case (21) Lower case (41) ...Lifter (43)...Fixed part (45)...Bending part (47)...First movable part (49)...Second movable part 11

Claims (1)

[Scope of Claims] A pair of cases having a magnetic disk for recording information, a disk holding surface for holding the magnetic disk, and rotatably housing the magnetic disk, and the disk holding surface of the pair of cases. A disk cartridge comprising: a liner for cleaning the magnetic disk installed in the magnetic disk; and a lifter installed on the disk holding surface of at least one of the pair of cases so as to press the liner against the magnetic disk; The lifter has a fixed part fixed to the disk holding surface of the case, a first movable part movable about the fixed part, and a first movable part extending from the first movable part in the direction of the fixed part. and a second movable part that presses the liner toward the magnetic disk through a bent part.