JPH03260975A - Cassette for storage disk - Google Patents

Abstract

PURPOSE:To prevent a projection from being held in a gap by inclining the joint surface of a half shell with respect to a surface which divides a shell into equal halves in a thickness direction at the terminating end surface of the shutter closing direction of a groove which guides the projection of a shutter. CONSTITUTION:The groove 5 which guides the projection 4 provided on the shutter 2 is formed to the shell. Then, the joint surface of the half shell is inclined with respect to the surface which divides the shell in half in the thick ness direction at the terminating end surface 51 of the shutter closing direction of the groove 5. As the result, even in the case that the gap forms on the joint surface, the projection 4 is not held in the gap even when the shutter 2 is pressed by a spring 3 and it abuts on the terminating end surface 51 of the groove because the gap forms to a position which is deviated from the projec tion 4. Thus, the actuation of the shutter is smoothly executed and the shutter is prevented from being deviated from a prescribed closed position.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a disk cassette of a type in which a storage disk such as a floppy disk is stored therein and the disk can be rotated and recorded and reproduced from the outside.

(Prior Art) As shown in an exploded perspective view in FIG. 5, a disk cassette stores a disk in a shell 1 having an opening 11 for inserting a recording/reproducing head, and has a head on the outer surface of the shell 1. A shutter 2 for opening and closing the insertion opening 11 is attached.

The shutter 2 has a U-shaped cross section consisting of a front plate 21, a rear plate 22, and an end plate 23 connecting the two.
A spring locking protrusion 4 is formed vertically upward inward.

This shutter 2 is installed in a shallow recess 12 provided in the shell 1, and is slidably engaged with a groove 13G of the shell 1, with a spring latched to the protrusion 4 so as to normally close the opening 11. is biased in the closing direction. Correspondingly, a groove 5 for guiding the spring locking projection 4 is provided on the end face of the shell 1.

The shutter 2 has conventionally been made of metal, but it has been proposed that it be made of plastic for the purpose of reducing weight and preventing the shell from being scraped during sliding.

(Problem to be Solved by the Invention) However, since the shell 1 is constructed by joining two half shells 1a and 1b, when the shell is subjected to a fall f# blow or when the shell is thermally deformed, the two half shells There was a risk that a gap would be created between the half shells and the protrusion 4 would get caught.

To explain this with reference to FIG. 6, FIG.
- A cross-sectional view from Vl, half shells 1a, 1b
This shows a state in which the protrusion 4 has entered the gap 1c created between the two.

That is, since the plastic shutter is more easily deformed than the metal shutter, the shutter 2 biased by the spring may come off the recess 12 and ride on the thick inside of the shell 1. The protrusion 4 in contact with the terminal end surface 51 of 5 enters the gap IC. As a result, the shutter 2 will move far from the specified closed position, deform and expand, causing the shutter 2 to get caught when attached to the device, the protrusion 4 to be damaged, and the shutter 2 not to open and close smoothly. There was a risk of

(Means for Solving the Problems) The present invention improves the above-mentioned drawbacks, and prevents the protrusion 4 of the shutter 2 from entering the gap in the shell 1.

The present invention will be explained in detail below with reference to the drawings.

Fig. 1 is a partially cutaway front view of the main part of the cassette of the present invention with the shutter attached to the shell, Fig. 2 is an enlarged end view taken from Fig. 1 - ■, and Figs. 3 and 4 are FIG. 2 is an enlarged end view taken from the same position as FIG. 2 showing different examples of the cassette of the present invention.

Since the shutter 2 in the cassette of the present invention is the same as the conventional one, the front plate 21,
It has a U-shaped cross section consisting of a rear plate 22 and an end plate 23, and the spring locking projection 4 stands up almost perpendicularly to the end plate 23.

The thickness is usually about 0.2 to 0.4 mm.

On the other hand, as shown in FIG. 1, the shell 1 is provided with a groove 5 on the end surface for guiding the protrusion 4. At the end surface 51 of the eraser 5 in the shutter closing direction, as shown in FIG.
A joint surface 1d of the half shells 1a and 1b is inclined with respect to a plane XX that equally divides the shell 1 into two in the thickness direction.

As a result, even if a gap is formed on the joint surface 1d, the gap is located at a position shifted from the protrusion 4, so even if the shutter 2 is biased by the spring 3 (FIG. 1) and comes into contact with the end surface 51 of the groove. , the protrusion 4 is not pinched.

The angle θ of the joint surface 1d relative to the The above may be sufficient.

FIG. 3 shows another example of the cassette of the present invention, in which the joint surface 1d
is offset from the plane XX by a distance t.

The distance t is preferably 0.2 mm or more in the case of a 3.5 inch floppy disk cassette.

Further, in the example shown in FIG. 4, the half shells 1a and 1b fit together to form an uneven joint surface 1d.

In the present invention, the position of the other joining surfaces does not matter as long as the groove terminal surface 51 has the above configuration.

In order to shift the joint surface from the XX plane, the shape of the relevant portion may be made asymmetric between the front and back sides during injection molding of the half shell.

In the present invention, preferably, when the shutter 2 is in a predetermined closed position, the protrusion 4 or the terminal surface 51 of the groove 5 is brought into contact with the shutter 2 .

That is, in the past, when the shutter 2 came to a predetermined closed position, the protrusion 4 did not come into contact with the terminal end surface 51 of the i5, so the shutter 2 sometimes came off from the recess 12 of the shell. Therefore, by making the groove 5 shorter than before or changing the position, width, etc. of the protrusion 4, the shutter 2 is brought into contact with the closing direction end of the recess 12 of the shell 1, as shown in FIG. The protrusion 4 is made to touch the terminal end surface 51 of the spring 5 immediately before.

As a result, when the shutter 2 reaches the predetermined closed position, the protrusion 4 comes into contact with the groove end surface 51, and since the protrusion 4 does not enter the gap between the shells, it is ensured that the shutter 2 comes off from the recess 12. can be prevented.

The present invention is suitable for a disc cassette equipped with a plastic shutter, and specific materials for the shutter include ABS resin, polycarbonate, polyvinyl chloride, polyester, and the like.

If the shutter 2 is made of plastic, it can be manufactured by injection molding or by folding a plastic sheet, but the sheet folding method is particularly preferred because it allows a thin shutter to be obtained, and since the sheet is thin, In addition to solving the above-mentioned problems occurring in the above, it is possible to obtain a lightweight cassette with no shell abrasion.

(Effects of the Invention) According to the present invention, in the shutter closed position, the spring locking protrusion does not enter the gap between the shells, the shutter operates smoothly, and the shutter can be enlarged from the predetermined closed position. Is it possible to prevent this?

[Brief explanation of drawings]

Fig. 1 is a partially cutaway front view of the main part of the cassette of the present invention with the shutter attached to the shell, Fig. 2 is an enlarged end view taken from Fig. 1 - ■, and Figs. 3 and 4 are FIG. 5 is an expanded perspective view of a conventional cassette, and FIG. 6 is a state in which a shutter is attached to the shell. - Main part sectional view from Vl. 1... Shell 1a, 1b... Half shell 1
d...Joint surface 11...Head insertion opening 2...
・Shutter 22...Rear plate 3...Spring 5...Groove 21...Front plate 23...End plate 4...Protrusion 51...Terminal surface of groove

Claims (1)

[Claims] A shell formed by joining two half shells, a shutter with a U-shaped cross section for opening and closing the head insertion opening of the shell, and a spring that biases the shutter to the closed position. In a storage disk cassette, in which one end of a spring is locked to an inward protrusion provided on an end plate that connects to a rear plate, and a groove for guiding the protrusion is provided on the end face of the shell, the terminal end of the groove in the shutter closing direction. A storage disk cassette characterized in that a joining surface of two half shells is offset from a surface dividing the shell into two equal parts in the thickness direction.