JPH11328917A - Magnetic tape cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic tape cassette, a lid lock spring of which does not separate off from the proper mounting position of a lower half at the time of assembling the magnetic tape cassette. SOLUTION: The problem is resolved by providing the magnetic tape cassette such as holding means 3, 5, 7, 8, 61a are arranged on the lower half 61 for holding the lid lock spring 1 to the proper position in the manner of shifting the coil part 1b, which is furnished on the lid lock spring 1 pressing the lid lock to the closed state, to the radial direction.

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 or the like.
More specifically, the present invention relates to a magnetic tape cassette provided with a lid lock for locking a lid that covers an opening at the front end of a cassette case so as to be freely opened and closed.

[0002]

2. Description of the Related Art There are various types of conventional magnetic tape cassettes. For example, there is a magnetic tape cassette 60 for a digital video cassette (DVC) as shown in FIG.

As shown in FIG. 3, a pair of reels 62 and 63 composed of upper and lower flanges are rotatably housed in a magnetic tape cassette 60 in a lower half 61 forming a cassette case half. A magnetic tape (not shown) is wound around the reels 62 and 63.

Each of the reels 62, 63 has an upper flange 84,
85 and lower flanges 70 and 71, and the lower flange 7
Engagement teeth are formed on the entire periphery of 0,71. The reels 62 and 63 are connected to the leaf spring 5
1 and 52 urges the lower half 61 side. 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. 3) and passes through the opening 67 on the front side of the lower half 61.

A lid 69 for covering a magnetic tape passing through an opening 67 at the front end of the cassette is provided on an upper half 75 as the other half forming a cassette case together with the lower half 61.
Is attached to open and close freely. This lid 69
It is composed of three members, an outer lid 76, a top lid 77, and an inner lid 78.

A lock pin 80 projects from the inside of the side plate 79 of the outer lid 76. A lid lock 8 that locks the lock pin 80 and locks the lid 69 in the closed state of the opening 67 on the side plate portion of the lower half 61.
2 is rotatably mounted. Further, a lid lock spring 83 for urging the lid lock 82 to the closed state of the lid 69 is provided on the rear side of the cassette of the lid lock 82.

[0007] As shown in FIG.
A ring portion 83b is formed at one end of a wire spring 83a, and the ring portion 83b is mounted on a mounting pin 84a of a columnar boss 84 formed on the lower half 61.
Guide member 8 having a free end intermediate portion provided on a part of the side plate portion.
7 is engaged with a guide groove 87a formed at the upper end of the cover 7 and attached to the lower half 61 to urge the lid lock 82 in the lock direction A. The mounting pin 84a is connected to the wire spring 8
3a takes such an engaged state, so that the upper half 75
Have sufficient height to be able to be temporarily fixed until they are put on the lower half 61.

When the upper half 75 is put on the lower half 61, the guide groove 72 a of the guide member 72 projecting from the inner wall surface of the upper half 75 is connected to the line formed by the cylindrical boss 84 and the guide member 87. The wire spring 83a is positioned from above by engaging with the intermediate portion of the spring 83a from above. Therefore,
The free end of the wire spring 83a is on the upper half 75 side (upper side).
To engage with the lid lock 82 to urge it to the closed state.

When the lid lock 82 is mounted on the lower half 61, the upper half 75 is connected to the lower half 61.
Then, the cassette case is turned upside down and the lower half 61 is turned up, and the screw 90 shown in FIG.
With a screwdriver or the like to complete the assembly.

[0010]

However, when the cassette case is turned over and the lower half 61 is turned up,
Until the upper and lower halves 75 and 61 are screwed by the screw 90, the lower halves 6 are biased by the leaf springs 51 and 52.
1 slightly floats from the upper half 75. Here, it is sufficient that the ring portion 83b of the lid lock spring 83 is tightly fitted to the mounting pin 84a. However, if the ring portion 83b is loosely fitted to the mounting pin 84a due to an error at the time of manufacture, etc., the lower half There is a problem in that the ring portion 83b comes off the mounting pin 84a while the 61 is floating from the upper half 75, and the wire spring 83a rotates around the mounting pin 84a due to vibration or the like.

The two guide grooves 72a and 82a are slightly different in position along the extending direction of the wire spring.
In the state where 1 is floating from the upper half 75, the guide grooves 72a, 8
There is a gap between 7a. Therefore, the wire spring 83a
Is rotated by vibration or the like, and once separated from the guide grooves 72a, 87a, when the upper and lower halves 61, 75 are to be tightened with screws, the wire spring 83a is moved by the guide grooves 72a, 8a.
7a, it cannot be returned, and it cannot be assembled properly.

Further, even after the cassette is assembled, the wire spring 83a causes the guide groove 72 by the impact when the cassette is dropped.
a, 87a. To prevent such a problem beforehand, the ring portion 83b and the mounting pin 84a
The ring portion 83b and the mounting pin 84a need to be formed with high precision.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a magnetic tape cassette in which a lid lock spring does not separate from a proper mounting position of a lower half when assembling the magnetic tape cassette.

[0014]

SUMMARY OF THE INVENTION The object of the present invention is to provide a cassette case comprising upper and lower halves and having an opening at a front end, and a cassette which is urged toward the lower half by a leaf spring. A reel that is rotatably housed and winds a magnetic tape, a lid that opens and closes the magnetic tape that passes through the opening, a lid lock that locks the lid in a closed state of the opening, and the lid. A lid lock spring for urging the lock to the closed state of the lid, the lid lock spring comprising a cantilever spring having one end locked to the lower half, and a free end of the lid lock spring from the upper half side. In a magnetic tape cassette that engages with a lid lock and urges it to a closed state, the lid lock spring includes a coil portion, and the coil portion is displaced in a radial direction. Ri is accomplished by providing a magnetic tape cassette holding means for holding the lid lock spring in the correct position, characterized in that provided in the lower half.

According to the magnetic tape cassette of the present invention, when the upper half is assembled to the lower half, the cassette case is turned over, and the screwing is performed with the lower half upward, the urging force is applied to the lower half by the leaf spring. Even if a gap is generated between the side walls of the upper and lower halves, the coil portion of the lid lock spring is shifted in the radial direction by the holding means provided on the lower half, and the lid lock spring is held at an appropriate position. . Therefore, since the lid lock spring does not come off from the proper position, the upper and lower halves are properly tightened by the screw and the magnetic tape cassette is assembled, so that the assemblability is improved.
In addition, the lid lock spring does not come off from the proper mounting position due to the impact when the cassette is dropped after the assembling, and a highly reliable lid lock can be guaranteed.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the accompanying drawings. The same components as those of the conventional magnetic tape cassette shown in FIGS. 3 and 4 are denoted by the same reference numerals and described. FIG. 1 is an inner view of the vicinity of a side plate portion of a lower half of a magnetic tape cassette according to an embodiment of the present invention, and FIG. 2 is a partial cross-sectional view when a lid lock and a lid lock spring are assembled to the lower half.

As shown in FIG. 1 and FIG.
A guide member 87 is provided on the side plate portion. The lid lock 82 is supported by a notch 61a formed on the side wall of the guide member 87 and supported by the shaft portion 82a so as to be swingable. And the wire spring 1 of the lid lock spring 1
The free end of “a” acts on a projection 82 c in a vertical slit 82 b formed in the lid lock 82. Therefore, the lid lock 82 is supported by the shaft portion 82a, and is urged in the locking direction A by receiving a force from the wire spring 1a to the protrusion 82c.

A support portion 9 for supporting the coil portion 1b of the lid lock spring 1 is provided on the rear side of the cassette of the guide member 87, and ribs 3, 5, 7 serving as holding means formed on the support portion 9. And the coil portion 1b of the lid lock spring 1.
A rib 8 is provided as a holding means that comes into contact with the rear end portion 1c. Each of the ribs 3, 5, and 7 is formed in a flat plate shape and has substantially the same width and thickness. The width of each of the ribs 3, 5, 7 is approximately half of the axial length of the coil portion 1 b of the lid lock spring 1, and the upper end thereof is tapered to guide the insertion of the lid lock spring 1. Consists of a shape. If the length of the wire spring 1a of the lid lock spring 1 is increased by a predetermined amount, or if the diameter of the coil portion 1b is increased, the support portion 9 does not need to be provided.

The distance between the ribs 3 and 7 is
And the distance between the side plate 61a as the holding means. The ribs 3 and the ribs 5 and the ribs 7 and the side plates 61a are respectively positioned in parallel. Therefore, as shown in FIG. 1, if the coil portion 1b of the lid lock spring 1 is accommodated in the ribs 3, 5, 7, the side plate 61a and the rib 8, the coil portion 1b is shifted in the radial direction. Become. Therefore, the rear end 1c of the coil portion 1b contacts the rib 8, a part of the end of the coil portion 1b contacts the rib 3 and the side plate 61a, and the substantially central portion of the coil portion 1b contacts the rib 5 and the rib 7. The abutment holds the lid lock spring 1 immovably. Note that a configuration may be used in which a rib is separately provided to abut the coil portion 1b without using the side plate 61a.

Next, a method of assembling the above-described magnetic tape cassette will be described. First, a reel and other various components are stored in the lower half 61. And lid lock 8
The second shaft portion 82a is swingably mounted in the notch 61a of the guide member 87, and then the coil portion 1b of the lid lock spring 1 is mounted.
Are housed in the ribs 3, 5, 7, the side plate 61 a and the rib 8. Further, the closed state of the lid 69 is locked by the wire spring 1a of the lid lock spring 1 abutting on the projection 82c in the slit 82b of the lid lock 82 to urge the lid lock 82 in the locking direction A.

Next, the upper half 7 to which the lid 69 is attached
5 is attached to the lower half 61. Thereafter, screwing is performed using the screw 90 with the cassette case turned upside down and the lower half 61 turned up. Here, the biasing force is applied to the lower half side 61 by the leaf springs 51 and 52 attached to the upper half 75, and the lower half 61 floats and a slight gap is formed between the side wall of the upper half 75 and the side wall of the lower half 61. Occur. However, the ribs 3, 5, 7, the side plate 61a, and the rib 8 displace the coil portion 1b of the lid lock spring 1, and the lid lock spring 1 is held at an appropriate position. Can be prevented from falling off. Therefore, the upper and lower halves are appropriately tightened by the screw, and the magnetic tape cassette is assembled, so that the assemblability is improved. Also, by the action of the ribs 3, 5, 7, the side plate 61a, and the rib 8, the lid lock spring does not come off from the proper mounting position due to the impact when the cassette is dropped after assembly, so that the lid having high reliability is provided. Lock can be guaranteed.

The embodiment of the present invention has been described above.
The present invention is not limited to the above-described embodiment, and can be appropriately changed and improved based on the spirit of the present invention. For example, the magnetic tape cassette of the present invention is not limited to DVC, but can be applied to various cassettes having a lid lock spring provided with a coil unit for urging the lid lock. Further, the shape and position of the holding means for holding the lid lock spring at an appropriate position are not limited to the above-described embodiment. For example, by disposing a plurality of cylindrical protrusions and displacing the coil portion, A configuration for holding the information may be used.

[0023]

As described above, according to the present invention, the lid lock spring has the coil portion, and the coil portion is displaced in the radial direction to hold the lid lock spring at an appropriate position. Since the means are provided in the lower half, the lid lock spring does not disengage from the proper position.
Therefore, the upper and lower halves are appropriately tightened by the screw, and the magnetic tape cassette is assembled, so that the assemblability is improved. In addition, the lid lock spring does not come off from the proper mounting position due to the impact when the cassette is dropped after the assembling, and a highly reliable lid lock can be guaranteed.

[Brief description of the drawings]

FIG. 1 is an inner view of the vicinity of a side plate portion of a lower half of a magnetic tape cassette according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view when a lower half lid lock and a lid lock spring are assembled.

FIG. 3 is an exploded perspective view of a conventional magnetic tape cassette.

FIG. 4 is an enlarged perspective view showing the vicinity of a side plate portion of a lower half.

[Explanation of symbols]

 1 lid lock spring 1a wire spring 1b coil part 3,5,7,8 rib 51,52 leaf spring 60 magnetic tape cassette 61 lower half 61a side plate 62,63 reel 69 lid 75 upper half 82 lid lock

Claims (1)

[Claims] 1. A cassette case comprising upper and lower halves and having an opening at a front end, and rotatably housed in the cassette case while being urged toward the lower half by a leaf spring, and wound with a magnetic tape. A lid for opening and closing the magnetic tape passing through the opening; a lid lock for locking the lid in a closed state of the opening; and urging the lid lock to a closed state of the lid. A lid lock spring comprising a cantilever spring having one end locked to the lower half, the free end of which is engaged with the lid lock from the upper half side to close the lid. In the biasing magnetic tape cassette, the lid lock spring includes a coil portion, and the coil portion is displaced in a radial direction so that the lid lock spring is moved. Magnetic tape cassette holding means for holding the positive position, characterized in that provided in the lower half.