JPH10247374A - Magnetic tape cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic tape cassette capable of reducing the cost and having good assembling easiness, by forming a lid lock spring in a with high versatility. SOLUTION: The magnetic tape cassette 1 is provided with a pair of freely turnably mounted reels 62, 63 on which magnetic tapes are wound and an opening part 67 is arranged at front ends of cassette cases 61, 75 and also an outer lid 76 is mounted for covering the magnetic tape passing through the opening part 67 so as to be freely openable/closable, then the lid lock 82 for locking the lid 76 so as freely closing the opening part 67 and a compression coil spring 11 for energizing this lid lock 82 so as to close the lid 76 are furnished. On the side plate part 81 of the cassette case, a spring accepting means capable of restraining the end part of one side of the compression coil spring 11 is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic tape cassette suitable for application to a video tape cassette and the like.
The present invention relates to a lid lock spring that biases a lid lock that locks a lid that opens and closes an opening at a front end of a cassette case, and a magnetic tape cassette with improved incorporation thereof.

[0002]

2. Description of the Related Art There are various types of conventional magnetic tape cassettes. For example, there is a relatively small magnetic tape cassette as shown in FIG. In the magnetic tape cassette 6, a pair of reel hubs 62 and 63 are rotatably arranged in a lower half 61, and a magnetic tape (not shown) is wound around the two reel hubs 62 and 63. The magnetic tape is guided by tape guides 65 and 66 on the left and right sides in front of the cassette (left side in FIG. 5), and passes through the opening 67 on the front side of the lower half 61. The teeth (70, 71) extend over the entire periphery (the periphery of the lower flange) of the reel hubs (62, 63).
Are formed.

On the other hand, when the magnetic tape cassette 6 is not loaded on a video deck (not shown), that is, when the cassette is stored or carried, the magnetic tape is prevented from being loosened on the rear side of the cassette. Reel hub 6
2 and 63, the reel hub 6
A slide member 72 which constitutes a reel lock device for preventing the rotation of the reel brakes 63, 63, that is, locks, the reel brakes 73, 73 serving as engaging claws, and the reel brake 7
A brake spring 74 for urging the members 3 and 73 in the locking direction via the slide member 72 is provided.

In the upper half 75, a lid for covering the magnetic tape passing through the opening 67 in front of the cassette case is composed of three parts, an outer lid 76, an upper lid 77, and an inner lid 78, which can be opened and closed freely. Installed. The side plate 79 of the outer lid 76
Has a lock pin 80 protruding therefrom. The outer lid 76 is provided on one side plate portion 81 of the lower half 61.
A lid lock 82 that locks the lock pin 80 to close the opening 67 and locks the opening 67 is rotatably mounted. Further, a lid lock that biases the lid lock 82 to close the outer lid 76 is provided. A leaf spring 83 as a spring is attached.

Reference numeral 85 in the figure denotes an upper flange of the reel hub, and reference numeral 86 denotes a lid spring mounted on a rotation shaft of the outer lid 76. In the figure, the members other than the main part are not denoted by the reference numerals, and the description is omitted.

[0006] As shown in an enlarged view in FIG. 6 (an arrow view of a portion along the section AA in FIG. 5), the shape of the leaf spring 83 presses the lid lock 82 when viewed from the side. And a curved portion 83a extending so as to engage with the lower half. That is, the leaf spring 83 has a curved portion 83a on the opposite side to the portion pressing the lid lock 82.
Is elastically deformed and inserted between the rib 88 protruding from the bottom wall or the side wall of the lower half 61 and a part 87 of the side wall facing the rib 88. With such an engagement state, the leaf spring 83 is temporarily fixed until the upper half 75 is covered.

[0007]

However, in the conventional magnetic tape cassette 6, since the leaf spring 83 is a leaf spring bent into a shape corresponding to the mounting portion as described above, a special spring is used. Will be used,
There is no versatility that can be used in other parts, causing an increase in cost.

In order to mount the leaf spring 83, the rib 88 must be formed on the lower half 61 as described above. When such a rib 88 is formed on the lower half 61, deformation due to shrinkage is likely to occur near the rib 88 when the lower half 61 is formed. Therefore, it is difficult to maintain good molding accuracy of the mounting portion of the leaf spring 83. On the other hand, since the leaf spring 83 is an extremely small elastic member, it is relatively difficult to improve the accuracy of sheet metal, bending, and the like.

As described above, conventionally, the processing accuracy of the leaf spring 83 is difficult to stabilize, and the molding accuracy of the mounting portion is also difficult to stabilize. However, there is a possibility that a situation may occur where the assembly is displaced from a predetermined mounting position, or in some cases jumps out of the lower half 61, resulting in extremely poor assemblability. In particular, when an automatic installation device or the like is used, this leaf spring 83
There has been a problem that automatic assembly becomes difficult.

Accordingly, an object of the present invention is to solve the above-mentioned problems, and to provide a magnetic tape cassette which can be reduced in cost and is easy to assemble by making the lid lock spring a highly versatile form. It is in.

[0011]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a cassette case having a pair of reels rotatably mounted by winding a magnetic tape, having an opening at a front end of a cassette case, and opening the opening. A lid for covering the magnetic tape passing therethrough so as to be openable and closable, and a lid lock for locking the lid to close the opening; and a lid lock spring for urging the lid lock to close the lid. Wherein the lid lock spring comprises a compression coil spring, and a side plate portion of the cassette case is provided with a spring receiving means capable of engaging one end of the compression coil spring. This is achieved by a magnetic tape cassette.

In a preferred embodiment, the spring receiving means comprises an engaging means which is open toward the front of the cassette case and forms a spring storage space which widens toward the rear of the cassette case.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A case where a magnetic tape cassette according to the present invention is applied to a video tape cassette will be described below in detail with reference to FIGS. FIG.
1 is an exploded perspective view showing a video tape cassette 1 to which a magnetic tape cassette according to an embodiment of the present invention has been applied. Since the video tape cassette 1 shown in FIG. 1 is substantially the same as the conventional magnetic tape cassette 6 (FIG. 6), the same parts as those in the related art are denoted by the same reference numerals and description thereof will be omitted as appropriate.

The video tape cassette 1 is different from the conventional one in that a compression coil spring 11 is used as a lid lock spring, and the compression coil spring 11 is attached to a side plate portion 81 of the lower half 61.
The spring receiving means 10 is provided with locking portions 13 and 14 capable of locking the spring and a spring storage space 12 formed by the locking portions.

As shown in FIG. 2, in this embodiment, the spring accommodating space 12 is in the form of a deep groove extending toward the rear of the cassette along the direction in which the compression coil spring 11 is urged. Are provided with the locking portions 13 and 14 protruding toward the other side. Then, as shown in FIG. 3, the width b1 on the back side of the spring storage space 12 is
1 and the distance W between the locking portions 13 and 14 is smaller than the diameter D of the compression coil spring 11.

When the compression coil spring 11 is mounted, the compression coil spring 11 is inserted from above the lower half 61, and its end is inserted into the spring storage space 12. Then, the locking portions 13 and 14 enter between the first and second turns, for example, from the end side of the compression coil spring 11, and the compression coil spring 11 is locked. Therefore, the compression coil spring 11 is positioned in a seated and stable state.

As described above, since the video tape cassette 1 uses the compression coil spring 11 as a lid lock spring, a compression coil spring in which the lid lock spring is used for other parts, such as a reel lock device, is used. And the brake spring 74 for urging the slide member 72 in the locking direction can be used in common.

Further, since the spring receiving means 10 capable of locking the compression coil spring 11 is provided on the side plate portion 81 of the lower half 61, the seating of the compression coil spring 11 is improved. It is possible to prevent the compression coil spring 11 from displacing or jumping out when assembling. Therefore, automatic assembly becomes easy. Further, since the displacement of the compression coil spring 11 during use of the completed video tape cassette 1 can be prevented, there is no risk of malfunction.

In the above-described embodiment, the case where the locking portions 13 and 14 of the spring receiving means 10 are provided continuously over the entire height of the spring accommodating space 12 has been described. Like the spring receiving means 20, the spring storage space 15
A structure in which a plurality of locking portions 16, 17, 18 are partially provided at an edge portion of the frame. Further, the bottom surface of the spring storage space 15 may be formed in an arc shape.

[0020]

As described above, according to the magnetic tape cassette of the present invention, since the compression coil spring is used as the lid lock spring, it is shared with the compression coil spring used in other parts. As a result, the cost can be reduced.

Further, since the spring accommodating means for locking the end of the compression coil spring is provided on the side plate of the cassette case, the locking of the spring can be ensured. Furthermore, since a rib for locking the spring is not required as in the conventional case, the resin shrinkage during molding of the cassette case can be reduced and deformation during molding can be prevented, as compared with the case where the rib is provided as in the conventional case. It is possible to provide a magnetic tape cassette that can be accurately attached by a spring and that can be easily assembled.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a video tape cassette to which a magnetic tape cassette according to one embodiment of the present invention is applied.

FIG. 2 is an enlarged perspective view of a main part showing a compression coil spring and spring receiving means shown in FIG. 1;

FIG. 3 is a plan view showing dimensions of each part of a compression coil spring and spring receiving means shown in FIG. 2;

FIG. 4 is a perspective view showing a modification of the spring receiving means.

FIG. 5 is an exploded perspective view showing a conventional video tape cassette.

FIG. 6 is an enlarged sectional view of a main part showing a conventional lid lock spring.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Video tape cassette 10 Spring receiving means 11 Lid lock spring 12 Spring storage space 13,14 Locking means 61 Lower half 62,63 Reel hub 76 Outer lid 81 Side plate part 82 Lid lock

Claims (1)

[Claims] 1. A cassette case comprising a pair of reels rotatably mounted around a magnetic tape, wherein an opening is provided at a front end of a cassette case, and the magnetic tape passing through the opening is openably and closably covered. A lid lock for locking the lid to close the opening, and a lid lock spring for biasing the lid to close the lid. A magnetic tape cassette, wherein the spring comprises a compression coil spring, and a spring receiving means capable of engaging one end of the compression coil spring is provided on a side plate of the cassette case.