JPH0643877Y2 - Magnetic disk body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a magnetic disk body, and more particularly to a magnetic disk body having an improved structure of a hub for supporting the magnetic disk.

[Conventional technology]

A conventional 2-inch magnetic disk cassette includes a magnetic disk body mainly composed of a magnetic disk, a container for rotatably housing the magnetic disk body, and a shutter for opening and closing a head insertion hole formed at one side edge of the container. It is equipped with. Further, the container is provided with a spindle insertion hole facing a hub made of a synthetic resin of a magnetic disk body and a rectangular head insertion hole adjacent to the spindle insertion hole and facing a recording / reproducing magnetic head. There is. The magnetic disk body includes an annular metal plate, a hub mounted along the inner peripheral edge of the annular metal plate, and a magnetic disk fixedly supported by both. Therefore, if the recording / reproducing apparatus is loaded with a magnetic disk cartridge, the drive shaft is inserted into the shaft hole of the hub and rotationally driven to rotate the magnetic disk body. It is configured to record information on the disc and reproduce the recorded information. Further, in order to smoothly rotate the magnetic disk body by the drive shaft, a metal leaf spring is fitted into a pair of grooves provided on the inner peripheral wall of the hub, and the leaf spring is inserted into the hub for driving. It is adapted to engage a part of the shaft. Further, the leaf spring has a bent portion formed at the lower end, and the bent portion prevents excessive deformation of the leaf spring.

[Problems to be solved by the device]

However, in the conventional magnetic disk body, when the leaf springs are supplied in accordance with the manufacturing of the magnetic disk body, two leaf springs are erroneously overlapped and supplied, and the two leaf springs supplied are used as they are in the hub. It was sometimes inserted in the groove.

In addition, in the conventional magnetic disk body, when a pencil or the like is inserted into the shaft hole of the hub by the carelessness of the user, the leaf spring is excessively deformed, and the magnetic disk body through which the drive shaft is inserted at the time of recording / reproducing. However, there was a problem in that it deviated from the reference position.

Therefore, the object of the present invention is to provide a magnetic disk body at the time of manufacture.
A magnetic disk capable of preventing excessive deformation of the leaf springs and securely chucking the drive shaft without mounting the two leaf springs even if one leaf spring is erroneously supplied. To provide the body.

[Means for Solving the Problems]

The present invention is directed to an annular metal plate supporting a magnetic disk and a hub mounted along the inner peripheral edge thereof, and a pair of grooves provided on both sides of a flat wall forming part of a peripheral wall of an axial hole of the hub. A magnetic disk body having a leaf spring having a bent portion directed toward the flat wall at the lower end, which is inserted into the flat wall. A flat protrusion and a second flat protrusion in the lateral direction are respectively formed, and the protrusion size of the first flat protrusion is made smaller than the protrusion size of the second flat protrusion. The object is achieved by providing a magnetic disk body characterized in that a difference obtained by subtracting the added dimension of the projecting dimension and the width dimension of the bent portion is made smaller than the thickness of the leaf spring.

[Action]

According to the present invention, when the leaf springs are mounted in the grooves of the hub in the magnetic disk body, even if two leaf springs are supplied in an overlapped manner, the second flat protrusions allow the leaf springs to reach the hubs of the two leaf springs. It is possible to prevent the leaf spring from being elastically inserted and prevent the leaf spring from being excessively deformed in the first flat projection of the shaft hole of the magnetic disk body, and the leaf spring elastically behaves to chuck the drive shaft. You can

〔Example〕

The present invention will be described below based on the embodiments shown in FIGS. In each drawing, FIG. 1 is a plan view showing the appearance of a 2-inch magnetic disk cassette to which an embodiment of the magnetic disk body of the present invention is applied, and FIG. 2 is a sectional view taken along the line II-II of FIG. FIG. 3 is a perspective view showing a state in which a leaf spring is attached to a hub of a magnetic disk body according to an embodiment of the present invention, and FIG. 4 is an enlarged plan view showing an essential part of the hub shown in FIG. 5
The figure is a front view taken along the line VV of FIG. 4, and FIG.
FIG. 7 is a sectional view taken along line VI-VI in FIG. 7, and FIG. 7 is a sectional view taken along line VII-VII in FIG.

A 2-inch magnetic disk cassette to which the magnetic disk body 2 of this embodiment is applied is rotated in a container 1 composed of a lower shell 11 and an upper shell 12 and a container 1 as shown in FIGS. And a magnetic disk body 2 that is freely accommodated. Further, the container 1 has a drive shaft insertion hole 1A through which the hub of the magnetic disk body 2 faces and a drive shaft is passed through the hub, and a rectangular shape that is adjacent to the drive shaft insertion hole 1A and faces a magnetic head for recording and reproduction. The head insertion hole 1B is formed, and the head insertion hole is formed.
A shutter S for opening and closing 1B is slidably attached to one side edge of the container 1.

Thus, the magnetic disk body 2 includes a magnetic disk 21 and
The hub body 22 supports the magnetic disk 21. As shown in FIGS. 2 and 3, the hub body 22 includes an annular metal plate 23, a synthetic resin hub 24 mounted along the inner peripheral edge of the annular metal plate 23, and an axial hole of the hub 24. 25 and a leaf spring 26 that crosses the plate 25 in one direction.

As shown in FIG. 3, the leaf spring 26 is formed in a substantially horizontally long rectangular shape, and has contact ends 26A, 2A with the hub 24 at both lateral ends thereof.
6A is formed, and a bent portion 26B for imparting strength to the leaf spring 26 is formed at the lower end between the contact ends 26A, 26A of the leaf spring 26. The leaf spring 26 is arranged along the flat wall 24A forming a part of the inner peripheral wall of the hub 24. Further, in the leaf spring 26, the contact end portions 26A, 26A are fitted and inserted in a pair of grooves 24B, 24B formed on both sides of the flat wall 24A. Then, a resin ring (not shown) is fitted so as to cover the hub 24 and a part of the metal plate 23, and the plate spring 26 is fixed to the hub 24 by the resin ring. In this state, the leaf spring 26 is reinforced by the bent portion 26B so as to elastically contact the drive shaft of the magnetic disk body with a predetermined spring force. The leaf spring 26 fixed to the hub 24 is a shaft hole of the hub 24.
When the drive shaft of the recording / reproducing apparatus is inserted into the drive unit 25, the drive shaft comes into contact with the drive shaft and deforms elastically to come into close contact with the drive shaft.
Is held at the reference position.

In addition, a vertical first flat protrusion 24C and a horizontal second flat protrusion 24D, which intersect each other in a cross shape, are formed wide in the horizontal center of the flat wall 24A of the hub 24 (see FIG. 5). reference). The first flat protrusion 24C is formed over the entire length in the height direction of the flat wall 24A to prevent the leaf spring 26 from excessively deforming when the magnetic disk cartridge is loaded, and the second flat protrusion 24C. 24D prevents the leaf spring 26 from being inserted incorrectly as described later.

Further, the protrusion dimension l ₁ of the first flat protrusion 24C is formed smaller than the protrusion dimension l ₂ of the second flat protrusion 24D (see FIG. 4) to prevent excessive deformation of the leaf spring 26 and to Hole
The elastic behavior range of the leaf spring 26 is ensured so that the drive shaft is surely chucked by the leaf spring 26 within 25. Further, since such a behavior region exists between the flat wall 24A and the leaf spring 26, even if the flatness of the second flat protrusion 24C becomes slightly rough due to the sink of the synthetic resin, Deformation can be suppressed within the range of elastic deformation to prevent settling.

Also, the protrusion dimension l of the second flat protrusion 24D from the flat wall 24A
₂ is the dimension δ of the gap of the groove 24B and the bent portion of the leaf spring 26.
It is set in relation to the width dimension w of 26B (see FIG. 7). That is, the value obtained by subtracting the added dimension (l ₂ + w) of the protruding dimension l ₂ of the second flat protrusion 24D and the width dimension w of the bent portion 26B from the gap dimension δ of the groove 24B is the thickness of the leaf spring 26. The protrusion dimension l ₂ of the second flat protrusion 24D is set to be smaller than t. By setting the projecting dimension ₂ of the second flat protrusion 24D in this way, even if _two overlapping leaf springs 26 are erroneously supplied, the width dimension w at the bent portion 26B of the leaf spring 26.
Is larger than the width of the bent portion 26B by the thickness t of the leaf spring 26, the contact ends 26A and 26A of the leaf spring 26 are not fitted into the grooves 24B and 24B of the hub 24, and It is designed to prevent insertion. In addition, the second flat protrusion 24D has the first flat protrusion 24D.
The flat protrusion 24C is formed by a left half portion 24D ₁ and a right half portion 24D ₂ that are continuously provided in both left and right directions.

Thus, the protrusion dimension l ₁ of the first flat protrusion 24C is 50 to 150.
μm is preferable, about 100 μm is more preferable, and its width is preferably about 1.5 mm. In addition, the second flat protrusion 24D
The protrusion size l ₂ of is preferably 150 to 250 μm, more preferably about 180 μm. Further, it is preferable that the second flat protrusion 24D is provided at a position about 1.3 mm from the upper end of the flat wall 24 and has a vertical width of about 600 μm.

Since the magnetic disk body 2 of this embodiment has the above-mentioned configuration, even if two leaf springs 26 are erroneously supplied at the time of manufacture, it is possible to insert the two leaf springs 26 as they are by the second flat protrusions 24D. Can be prevented. Further, even if a pencil or the like is inadvertently inserted into the shaft hole 25 of the hub 24 of the magnetic disk body 22, excessive deformation of the leaf spring 26 is prevented by the first flat protrusion 24C, and the drive shaft is secured by the leaf spring 26. The magnetic disk body 2 can be held at the reference position by chucking.

The present invention is not limited to the above embodiment, but the left half portion 24D ₁ and the right half portion 24D _{2 of} the second flat protrusion 24D integrated with the first flat protrusion 24C in a cross shape. And each may be separated from the first flat protrusion 24C. The point is that the first flat protrusion in the vertical direction and the second flat protrusion in the horizontal direction intersect with the flat wall in a cross shape at approximately the center in the horizontal direction. And the projection size of the first flat projection is smaller than the projection size of the second flat projection, and the projection size of the second flat projection and the projection size of the second flat projection from the clearance size of the grooves at the left and right ends of the flat wall. If the difference obtained by subtracting the additional dimension of the width of the bent portion is made smaller than the thickness of the leaf spring, it is all included in the present invention.

[Effect of device]

According to the magnetic disk body of the present invention, the first flat projections in the vertical direction and the second flat projections in the horizontal direction that intersect in a cross shape at approximately the center in the horizontal direction are respectively specified in the flat wall forming the axial hole of the hub. Since the protrusions are formed, even if two leaf springs are erroneously supplied at the time of manufacturing the magnetic disk body, it is possible to prevent excessive deformation of the leaf springs without attaching the two leaf springs. In addition, the drive shaft can be reliably chucked.

[Brief description of drawings]

FIG. 1 is a plan view showing the appearance of a 2-inch magnetic disk cassette to which an embodiment of the magnetic disk body of the present invention is applied,
2 is a sectional view taken along the line II-II of FIG. 1, FIG. 3 is a perspective view showing a state in which a leaf spring is attached to a hub of a magnetic disk body in an embodiment of the present invention, and FIG. 4 is a view of FIG. The top view which expands and shows the principal part of the hub shown, FIG. 5 is the front view from the VV line direction of FIG. 4, FIG. 6 is the VI-VI sectional view taken on the line of FIG. 4, and FIG. FIG. 7 is a sectional view taken along line VII-VII of FIG. 3. 2; magnetic disk body 21; magnetic disk, 23; annular metal plate 24; hub, 24A; flat wall 24B; groove 24C; first flat protrusion 24D; first flat protrusion 25; shaft hole, 26; leaf spring 26B; folding Music section

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Claims (1)

[Scope of utility model registration request] 1. A ring-shaped metal plate supporting a magnetic disk and a hub mounted along the inner peripheral edge of the plate, and a pair of flat walls formed on both sides of a flat wall forming part of a peripheral wall of an axial hole of the hub. In a magnetic disk body having a leaf spring fitted in a groove and having a bent portion toward the flat wall side at the lower end, a vertical first portion that crosses the flat wall in a cross shape at approximately the center in the horizontal direction. 1 flat protrusions and 2nd horizontal flat protrusions are formed respectively, and the projecting dimension of said 1st flat protrusions is made smaller than the projecting dimension of said 2nd flat protrusions. The magnetic disk body is characterized in that a difference obtained by subtracting the added dimension of the protruding dimension and the width dimension of the bent portion is smaller than the thickness of the leaf spring.