JPH0240632Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention is a method for storing magnetic disks such as micro floppy disks and other magnetic, electrostatic, optical, etc. recording and reproducing disks in a case. It relates to a disk cartridge, in particular, between a disk rotatably housed in a case, at least one recording surface of the disk, and an inner surface of the case opposite to the one recording surface. A disk cartridge comprising an interposed liner sheet and an elastic plate fixed to the inner surface of the case and inclined so as to elastically press the liner sheet to the disk at a tip end thereof. It is related to.

[Conventional technology]

The conventional technology for this type of disk cartridge will be explained using a micro floppy disk cartridge (hereinafter referred to as an MFD cartridge) shown in FIGS. 5 to 7.

First, as shown in FIG. 5, the MFD cartridge is equipped with a magnetic disk 1 and a case 2 that houses the magnetic disk 1, and this case 2 is used to connect a pair of upper and lower halves 3 and 4. It is formed by twisting. The magnetic disk 1 is made of a flexible polymer film with a recording surface formed on at least its lower surface, and a dish-shaped core metal 5 is provided at the center of the magnetic disk 1. A pair of small holes 6 are formed in this core metal 5, in which a center pin of a spindle of a magnetic recording/reproducing device (not shown) and a drive pin eccentric to the center pin engage. The magnetic disk 1 is configured to be rotated within the case 2.

Upper and lower halves 3 and 4 that make up case 2 are made of ABS
It is molded into a substantially square shape from a synthetic resin such as the like, and a protrusion 7 is formed on its peripheral edge. Then, by joining the upper and lower halves 3 and 4 with the tip surfaces of these protrusions 7 in contact with each other, the magnetic disk 1 is inserted inside the halves 3 and 4.
A case 2 is formed having a space for rotating the . A long hole 8 for inserting a magnetic head is formed in the lower half 4, and a long hole 9 for inserting a pad is formed in the upper half 3 corresponding to this long hole 8. Further, a circular hole 10 for inserting a spindle is formed in the lower half 4. Note that 17 is slidably attached to the case 2 with the upper and lower halves 3 and 4 in between, and is inserted into long holes 8 and 9.
It is a shutter that opens and closes.

A liner sheet 1 is provided between the upper half 3 and the magnetic disk 1 and between the lower half 4 and the magnetic disk 1.
These liner sheets 11 and 12 are partially fixed to the upper half 3 and the lower half 4 by ultrasonic welding or the like, respectively. These liner sheets 11 and 12 are made of a nonwoven fabric such as polyester or rayon, and are intended to apply an appropriate rotational load due to friction to the magnetic disk 1 within the case 2. The upper liner sheet 11 has an approximately rectangular cut 13 for inserting the pad and a circular hole 1 for the core bar 5.
4, and the lower liner sheet 12 is formed with a substantially rectangular cut 15 for inserting a magnetic head and a circular hole 16 for inserting a spindle.

An elastic plate 18 is arranged between the lower liner sheet 12 and the lower half 3. This elastic plate 18
is formed into a substantially rectangular shape using an elastic plastic film made of polyethylene terephthalate. The elastic plate 18 is bent into a substantially dogleg shape, and its fixed end portion 18a is fixedly supported on the inner surface of the lower half 4 by adhesive or the like. The inclined portion 18b bent from the fixed end portion 18a of the elastic plate 18 is inclined (i.e., , diagonally upward). The width of the elastic plate 18 is approximately equal to the recording track width of the recording surface of the magnetic disk 1.

Therefore, as shown in FIG.
c partially attaches the liner sheet 12 to the magnetic disk 1.
It is pressed onto the recording surface. As a result, the crimped portion of the liner sheet 12 forcibly removes foreign matter such as dust adhering to the recording surface of the magnetic disk 1 (so-called cleaning), and the foreign matter such as dust remains attached. This prevents the magnetic disk 1 from coming into contact with the magnetic head. Furthermore, by elastically pressing the liner sheet 12 onto the magnetic disk 1, a predetermined rotational load can be applied to the magnetic disk 1, and the rotational state of the magnetic disk 1 can be stabilized.

[Problem that the invention attempts to solve]

However, the conventional MFD cartridge described above has the following problems.

That is, the elastic plate 18 is made of polyethylene terephthalate and elastically presses the liner sheet 12 onto the magnetic disk 1 as a cantilever beam. Due to this, there was a problem of creep in high temperature environments. The elastic plate 18 gradually loses its effectiveness as a cantilever due to aging, and it is difficult to expect the elastic plate 18 to be effective in cleaning the magnetic disk 1 and stabilizing the rotational state over a long period of time. It was hot.

Therefore, in order to solve the above-mentioned creep problem, the present inventor considered thin metal plates such as stainless steel and plastic films such as polyester as materials for the elastic plate 18. However, although these materials improve the creep problem, the spring pressure of the elastic plate 18 changes rapidly in response to subtle changes in the height of the elastic plate 18 between the upper and lower halves 3 and 4. A problem had arisen.

In other words, as shown in Fig. 6, the upper and lower halves 3 and 4
Within the inner dimension H ₁ (approximately 1.4 mm) between the elastic plates 18
When the height of the tip portion 18c of the elastic plate 18 is normal (height h ₁ ), the tip portion 18c of the elastic plate 18 presses the liner sheet 12 against the recording surface of the magnetic disk 1. At this time, the distance between the fulcrum P of the elastic plate 18 and the point of action _Q1 is _l1 .

However, as shown in Figure 7, due to dimensional tolerances, changes over time, etc., the inner dimension H ₂ between the upper and lower halves 3 and 4
becomes smaller and the height of the tip portion 18c of the elastic plate 18 becomes lower (height h ₂ ), the elastic plate 18 bends and curves into an arc, and the central portion moves further inward from the tip portion 18c. The elastic plate 18 comes into contact with the liner sheet 12, and the distance between the fulcrum P of the elastic plate 18 and the point of action _Q2 located in the center changes to _l2 .
Note that the heights h ₁ and h ₂ mentioned above are approximately 0.9 mm to 0.9 mm in the actual usage range.
It is 0.4mm. When the height of the tip portion 18c of the elastic plate 18 is reduced in this way, the distance between the fulcrum of the elastic plate 18 and the point of action where the elastic plate 18 presses the liner sheet 12 becomes shorter, and as a result, the liner sheet 12 The applied spring pressure of the elastic plate 18 suddenly becomes stronger. As the pressure force of the liner sheet 12 against the magnetic disk 1 becomes stronger, too much rotational load is applied to the magnetic disk 1, making it impossible to obtain a stable rotational state of the magnetic disk 1. If the friction is too strong, the magnetic disk 1 will be scratched.

In this way, the spring pressure of the elastic plate 18 changes rapidly in response to a slight change in the height of the elastic plate 18. Due to the sudden change in spring pressure, it becomes difficult to always reliably obtain the effects of cleaning the magnetic disk 1 and stabilizing the rotational state by the elastic plate 18 as described above.

Further, the tip portion 18c of the elastic plate 18 easily bends in the width direction and curves into an arc shape, and the tip portion 18c of the elastic plate 18 presses the liner sheet 12 to the magnetic disk 1 only at the center portion in the width direction. It was easy to get into a state of being. As a result, there was a problem in that the cleaning of the magnetic disk 1 by the elastic plate 18 was performed only at the center of the recording surface of the magnetic disk 1 in the width direction.

Therefore, in the present invention, even if the internal dimensions of the case change slightly due to dimensional tolerances or aging, the point of action at which the elastic plate presses the liner sheet hardly changes, and the elastic plate The purpose of the present invention is to enable the liner sheet to constantly and uniformly contact substantially the entire width of the recording surface of the disk by the tip portion.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides the above-mentioned disk cartridge with a fixed end fixed to the tip portion of the elastic plate and the inner surface of the case. A plurality of first protrusions extending along the inclination direction and arranged at intervals in the width direction of the elastic plate are provided on the inclined part between the two parts, and a plurality of first protrusions are provided at the tip of the elastic plate. A second protrusion is provided extending along the width direction of the elastic plate.

[Effect]

According to the above-mentioned technical means, the plurality of first protrusions are provided on the inclined portion of the elastic plate so as to extend along the inclined direction, so that the stiffness of the inclined portion of the elastic plate in the inclined direction is significantly increased. It gets expensive. Therefore, even if the internal dimensions of the case change slightly due to dimensional tolerances or aging, and the height of the tip of the elastic plate changes slightly, the elastic plate will not bend and curve into an arc. Therefore, the point of action where the elastic plate presses the liner sheet hardly changes.

Moreover, the second protrusion provided at the tip of the elastic plate so as to extend along the width direction of the elastic plate significantly increases the rigidity of the tip of the elastic plate in the width direction. Therefore, the tip of the elastic plate does not bend in the width direction and curve into an arc, so the tip of the elastic plate keeps the liner sheet uniform over almost the entire width of the recording surface of the disk. can be contacted.

〔Example〕

An embodiment in which the present invention is applied to an MFD cartridge will be described below with reference to FIGS. 1 to 4.
Note that the same parts as those of the conventional example explained in the above [Prior Art] section are given the same reference numerals, and the explanation thereof will be omitted.

First, as shown in FIG. 1, the inclined portion 18b of the elastic plate 18 in this embodiment has a plurality of rods (for example, 4) first protrusions 20 are provided. These first protrusions 2
0 is the inclined portion 18b of the elastic plate 18 and projects downward (toward the lower half 4 side). Note that these first protrusions 20 do not reach the tip end portion 18c of the elastic plate 18, but are provided slightly inside the tip portion 18c.

Further, the tip portion 18c of the elastic plate 18 has a second protrusion 21 extending along the width direction of the elastic plate 18.
is provided. This second protrusion 21 is located on the upper side (liner sheet 12
protruding from the side). Note that this second protrusion 21 is not formed over the entire width of the elastic plate 18, and both ends 21a thereof are each slightly bent in the direction of inclination of the elastic plate 18.

The elastic plate 18 in this embodiment is made of a general spring metal thin plate such as a stainless steel plate, a phosphor bronze plate, or a nickel silver plate, or a plastic film made of polyester, polypropylene, polycarbonate, polyoxymethylene, etc. There is. In the case of a thin metal plate, the first and second protrusions 20 and 21 are stamped using a press, and the elastic plate 18 is punched out at the same time; in the case of a plastic film, the first and second protrusions 20 and 21 are stamped by heating, etc. 1. 2nd
After forming the protrusions 20 and 21, the elastic plate 18 is punched out using a press. Therefore, in any case, the elastic plate 18 having the first and second protrusions 20 and 21 can be easily molded in large quantities using a common material.

According to this embodiment configured as described above, first, as shown in FIG.
When the height of 8c is normal (height h ₁ ), the elastic plate 18
As in the prior art, the liner sheet 12 is pressed against the recording surface of the magnetic disk 1 at its leading end portion 18c. At this time, the fulcrum P of the elastic plate 18 and the point of action
The distance from Q ₃ is l ₃ .

By the way, since the inclined portion 18b of the elastic plate 18 has the first protrusion 20 extending along the inclined direction, the inclined portion 18b of the elastic plate 18
has significantly increased rigidity in the direction of inclination. Therefore, due to dimensional tolerances, aging, etc., the inner dimension _H2 between the upper and lower halves 3 and 4 becomes smaller, and as shown in FIG. h ₂ ) Even if it gets old, this elastic plate 18
will not bend into an arc. As a result, the elastic plate 18 can press the liner sheet 12 onto the recording surface of the magnetic disk 1 at its leading end portion 18c. That is, the point of action Q ₃ of the elastic plate 18 hardly changes, and the distance l ₃ between the fulcrum P and the point of action Q ₃
does not change substantially. In this way, the elastic plate 18
Even if the height of the elastic plate 18 changes, the distance l ₃ between the fulcrum P and the point of action Q ₃ that presses the liner sheet 12
does not change, so the spring pressure of the elastic plate 18 against the liner sheet 12 does not change suddenly.

In addition, FIG. 4 compares the relationship between the height of the elastic plate 18 formed of a thin stainless steel plate with a thickness of about 50 μm and the spring pressure between the conventional example (indicated by the dotted line) and the present example (indicated by the solid line). However, within the actual usage range a (approximately 0.4 mm to 0.9 mm) of the height of the elastic plate, the spring pressure of the conventional elastic plate changes rapidly as the height changes, but in this example, the spring pressure changes rapidly. The elastic plate does not have such sudden changes, but instead changes gradually.

Next, the tip portion 18c of the elastic plate 18 has a second protrusion 21 extending along the width direction of the elastic plate 18.
, the rigidity of the tip portion 18c of the elastic plate 18 in the width direction is significantly increased. Therefore, the tip portion 1 of this elastic plate 18
8c does not bend in the width direction and curve in an arc shape. As a result, the tip portion 18c of the elastic plate 18
liner sheet 1 at all times in its entire width direction.
2 can be uniformly pressed over almost the entire width of the recording surface of the magnetic disk 1.

Note that, since the second protrusion 21 of the tip portion 18c of the elastic plate 18 projects upward, the liner sheet 12 can be more securely pressed onto the magnetic disk 1 by the second protrusion 21. Therefore, the cleaning effect of the magnetic disk 1 can be greatly improved. That is, the present inventor turned pencil lead into powder and sprayed it onto the magnetic disk 1, and incorporated this magnetic disk 1 and the elastic plate 18 according to this embodiment.
As a result of confirming the cleaning effect of the elastic plate 18 on the magnetic disk 1 using an MFD cartridge, it was found that the elastic plate 18 according to this embodiment can remove particles attached to the magnetic disk 1 from the inside of the second protrusion 21 (the magnetic disk 1 (upstream side in the direction of rotation) in an extremely large amount (approximately 2 to 3 times that of conventional methods).

Although one embodiment of the present invention has been described above, various effective modifications can be made based on the technical idea of the present invention.

[Effect of idea]

As mentioned above, according to the present invention, even if the height of the elastic plate inside the case changes slightly due to the internal dimensions of the case changing slightly due to dimensional tolerances, aging, etc. Since the plate does not bend and curve into an arc, the point of action of the elastic plate that presses the liner sheet to the disk hardly changes, and the spring pressure of the elastic plate against the liner sheet changes the height of the elastic plate. It is possible to effectively prevent sudden changes in the Therefore, the effect of cleaning the disk and stabilizing the rotational state by the elastic plate can be guaranteed for a long period of time.

In addition, since the tip of the elastic plate does not bend in the width direction of the elastic plate and curve into an arc, the tip of the elastic plate can always securely record the liner sheet in the entire width direction of the disk. It is possible to apply pressure uniformly over almost the entire width of the surface. Therefore, the effectiveness of disk cleaning by the elastic plate can be significantly improved.

[Brief explanation of drawings]

Figures 1 to 4 show an embodiment in which the present invention is applied to a micro floppy disk cartridge. Figure 1 is a perspective view of an elastic plate, and Figure 2 is a perspective view of an elastic plate. Figure 3 is an enlarged cross-sectional view of the main part to explain the state in which the liner sheet is crimped to the magnetic disk. 4 are diagrams showing the relationship between the height of the elastic plate and the spring pressure. 5 to 7 show conventional examples of micro floppy disk cartridges. FIG. 5 is an exploded perspective view of the entire cartridge, and FIG. 6 shows a liner sheet supported by an elastic plate. FIG. 7 is an enlarged cross-sectional view of the main parts for explaining the state in which the elastic plate is pressed against the magnetic disk, and FIG. 7 is an enlarged cross-sectional view of the main parts similar to FIG. 6 in a state where the height of the elastic plate is lowered. In addition, in the symbols used in the drawings, 1...magnetic disk, 2...case, 11...liner sheet,
12...Liner sheet, 18...Elastic plate, 18a
...Fixed end portion, 18b...Slanted portion, 18c...
...Tip portion, 20...First protrusion, 21...Second
It is a ridge.

Claims (1)

[Scope of utility model registration request] A disk rotatably stored inside the case,
A liner sheet is interposed between at least one recording surface of the disk and the inner surface of the case opposite to the one recording surface, and the liner sheet is fixed to the inner surface of the case and is inclined, and has a tip portion. In a disk cartridge each comprising an elastic plate configured to elastically press the liner sheet to the disk, a tip portion of the elastic plate and a fixed end portion fixed to the inner surface of the case are connected. A plurality of first protrusions extending along the inclination direction and spaced apart in the width direction of the elastic plate are provided on the inclined part between the elastic plates, and the elastic plate is disposed at the distal end of the elastic plate. 1. A disk cartridge characterized in that a second protrusion extends along the width direction of the disk cartridge.