JPH0240633Y2 - - 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. 6 to 8.

First, as shown in FIG. 6, 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 toward the liner sheet 12 (i.e., , diagonally upward). The width of the elastic plate 18 in the radial direction of the magnetic disk 1 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. Further, 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. 7, 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 8, 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 of the liner sheet 12 against the magnetic disk 1 increases, 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 above-described effects of cleaning the magnetic disk 1 and stabilizing the rotational state of the magnetic disk 1 by the elastic plate 18.

Further, the conventional flat elastic plate 18 is easily bent in the width direction (radial direction of the magnetic disk 1) and curved into an arc shape, especially at the tip portion 18c of the elastic plate 18.
When the liner sheet 12 is bent in its width direction, the liner sheet 12 is likely to be pressed against the magnetic disk 1 only at the widthwise center of its tip portion 18c. Moreover, due to the deformation of the upper and lower halves 3 and 4, the elastic plate 18
If the tip end portion 18c of the elastic plate 18 is slightly inclined in the width direction, the contact state between the tip portion 18c and the liner sheet 12 of the flat elastic plate 18 changes, and the entire tip portion 18c of the elastic plate 18 changes. In this case, the liner sheet 12 could not be brought into constant uniform contact over almost the entire width of the recording surface of the magnetic disk 1, resulting in the inconvenience that cleaning of the recording surface of the magnetic disk 1 was partially missed.

Therefore, in the present invention, even if the internal dimensions of the case slightly change due to dimensional tolerances or aging, the point of action where 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 problems]

In order to solve the above-mentioned problems, the present invention provides the above-mentioned disk cartridge, in which the elastic plate is provided with a plurality of protrusions that protrude toward the liner sheet side and are close to each other over almost the entire surface of the elastic plate. The plurality of protrusions on at least the tip portion of the plate are arranged so that their respective widths overlap each other in the radial direction of the disk.

[Effect]

According to the above-mentioned technical means, the plurality of protrusions provided over almost the entire surface of the elastic plate significantly increases the rigidity of the elastic plate in the direction of inclination. 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.

Further, since the plurality of projections significantly increases the rigidity of the elastic plate in the width direction (radial direction of the disk), the tip portion of the elastic plate does not bend in the width direction and curve in an arc shape. Moreover, since the plurality of protrusions protrude toward the liner sheet side and their respective widths overlap each other in the radial direction of the disk, the tip of the elastic plate extends the liner sheet over almost the entire width of the recording surface of the magnetic disk. Uniform contact can be maintained at all times.

〔Example〕

An embodiment in which the present invention is applied to an MFD cartridge will be described below with reference to FIGS. 1 to 5.
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 of all, FIGS. 1 to 3 show a first embodiment, in which a plurality of protrusions 20 protrude toward the liner sheet 12 side (i.e., upper side) and are close to each other on the inclined portion 18b of the elastic plate 18. is provided over almost the entire surface. These plurality of protrusions 20 each have a substantially T-shape, and are arranged along the direction of inclination of the inclined portion 18b, which is the direction of rotation of the magnetic disk 1, and in the width direction of the elastic plate 18, which is the radial direction of the magnetic disk 1. are arranged in opposite directions. The plurality of protrusions 20 are arranged so that their respective widths ω overlap each other in the radial direction of the magnetic disk 1. Further, the lengths l of each of the magnetic disks are arranged so that they overlap with each other in the direction of rotation of the magnetic disk 1.

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 process of forming a plurality of protrusions 20 using a press and the punching process of the elastic plate 18 are performed at the same time, and in the case of a plastic film, the process of forming a plurality of protrusions 20 by heating or the like is performed simultaneously. After processing, the elastic plate 18 is made by pressing.
Perform the punching process. Therefore, in any case, the elastic plate 18 having a plurality of protrusions 20 can be easily molded in large quantities using common materials.

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 .

Incidentally, since the plurality of protrusions 20 are present over the entire surface of the inclined portion 18b of the elastic plate 18, the rigidity of the inclined portion 18b of the elastic plate 18 in the direction of inclination is extremely high. 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 the elastic plate 18 bends, the elastic plate 18 will not bend into an arc shape. 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 also does not substantially change. In this way, 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 elastic plate 18 The spring pressure of 18 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.

On the other hand, due to the plurality of protrusions 20 existing over almost the entire surface of the inclined portion 18b of the elastic plate 18, the rigidity of the elastic plate 18 in the width direction is also significantly increased. Therefore, the tip portion 18c of the elastic plate 18 does not bend in the width direction and curve into an arc. As a result, the tip portion 18c of the elastic plate 18 can always and reliably press the liner sheet 12 uniformly over almost the entire width of the recording surface of the magnetic disk 1 in its entire width direction.

Incidentally, since the plurality of protrusions 20 of the elastic plate 18 protrude upward, the liner sheet 12 can be pressed onto the magnetic disk 1 more reliably by the plurality of protrusions 20. For example, by deforming the upper and lower halves 3 and 4, the tip portion 18 of the elastic plate 18
Even if c is slightly inclined in the width direction, it is possible to ensure that the liner sheet 12 is pressed against the magnetic disk 1, and the cleaning effect of the magnetic disk 1 can be greatly enhanced. That is, the present inventor powdered pencil lead and sprayed it onto the magnetic disk 1, and by using an MFD cartridge incorporating this magnetic disk 1 and the elastic plate 18 according to this embodiment, the magnetic disk 1 by the elastic plate 18 was created.
As a result of confirming the cleaning effect of the elastic plate 18 according to this embodiment, it was found that the powder attached to the magnetic disk 1 was removed in an extremely large amount (approximately 2 ~3 times).

Moreover, since the plurality of protrusions 20 are arranged so that their respective widths ω overlap each other in the radial direction of the magnetic disk 1, the tip portion 18c of the elastic plate 18 is always reliably secured in its entire width direction. The liner sheet 12 can be uniformly pressed over almost the entire width of the recording surface of the magnetic disk 1, and there is no inconvenience such as the recording surface of the magnetic disk 1 being partially cleaned.

Next, FIG. 5 shows a second embodiment, in which, similarly to the above, the inclined portion 18b of the elastic plate 18 has a plurality of pieces protruding toward the liner sheet 12 side (i.e., upper side) and close to each other. Although the protrusions 21 are provided over almost the entire surface, these plural protrusions 2
1 is composed of substantially elliptical projections. The plurality of protrusions 21 are arranged so that their respective widths ω overlap each other in the radial direction of the magnetic disk 1, and their respective lengths 1 overlap each other in the rotational direction of the magnetic disk 1.

Also in this second embodiment, similarly to the first embodiment described above, the elastic plate 18 is
The rigidity of the inclined portion 18b in the inclination direction and the width direction is significantly increased.

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

For example, in the embodiment, the widths and lengths of the plurality of protrusions are arranged so as to overlap with each other in the radial direction and rotational direction of the disk, but the widths and lengths of these plurality of protrusions at least at the distal end portion of the elastic plate are It is sufficient that they overlap each other in the radial direction of the disk.

[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, the tip of the elastic plate does not bend in the width direction of the elastic plate and curve into an arc, and since the plurality of protrusions actively bring the liner sheet into contact with the disk, the tip of the elastic plate The liner sheet can always be reliably pressed uniformly over almost the entire width of the recording surface of the disk over its entire width. Therefore, the effectiveness of disk cleaning by the elastic plate can be significantly improved.

[Brief explanation of the drawing]

Figures 1 to 5 show an embodiment in which the present invention is applied to a micro floppy disk cartridge. Figure 1 is a plan view of an elastic plate in the first embodiment, and Figure 2 is a plan view of an elastic plate in the first embodiment. Figure 3 is an enlarged sectional view of the main part to explain the state in which the liner sheet is crimped onto the magnetic disk by the same elastic plate as above, and Figure 3 is the same as Figure 2 with the height of the elastic plate lowered. FIG. 4 is a diagram showing the relationship between the height of the elastic plate and the spring pressure, and FIG. 5 is a perspective view of the elastic plate in the second embodiment. 6 to 8 show conventional examples of micro floppy disk cartridges. FIG. 6 is an exploded perspective view of the entire cartridge, and FIG. 7 shows a liner sheet held by an elastic plate. FIG. 8 is an enlarged sectional view of the main parts for explaining the state in which the elastic plate is pressed against the magnetic disk, and FIG. 8 is an enlarged sectional view of the main parts similar to FIG. 7 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, 18c
... tip portion, 20 ... protrusion, 21 ... protrusion.

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, the elastic plate has a plurality of protrusions protruding toward the liner sheet side and close to each other on almost the entire surface. 2. A disk cartridge, characterized in that the plurality of projections on at least the tip end portion of the elastic plate are arranged such that their respective widths overlap with each other in the radial direction of the disk.