JPH11250613A - Magnetic tape cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic tape cassette which does not allow a lid lock spring to be disengaged from a lower half at the time of assembling a magnetic tape cassette. SOLUTION: A magnetic tape cassette is provided with a spring insertion rib 118 at the side wall of a mounting pin 116 provided at the bottom wall of a lower half 61. Moreover, an end widening spring fixing rib 120 is formed in a gap between the side wall of a guide spring 87 and a mounting pin 116. Moreover, a lid lock spring 110 is formed of a long-length line spring 112 and a coil spring type ring 114. The free end of the line spring 112 is in contact with a projection 82c within a slit 82b in the vertical direction formed in a lid lock 82 to bias the lid lock 82 in the locking direction A and thereby the ring 114 is fitted on the mounting pin 116. Winding height of the ring 114 is set larger than the gap between the upper and lower halves which are formed when these are assembled and the lid lock spring 110 is never disengaged from this gap.

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 use in a video tape cassette or the like, and more particularly, to a lid lock for closing a lid for opening and closing a front end opening of a cassette case in a closed state. The present invention relates to a magnetic tape cassette provided.

[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 as a digital video cassette (DVC) whose disassembly structure is shown in FIG.

As shown in FIG. 3, a pair of reels 62 and 63 composed of upper and lower flanges are rotatably accommodated in a lower half 61 forming a cassette case half. , 63 are wound with a magnetic tape (not shown). Each reel 62, 63
Is composed of upper flanges 84 and 85 and lower flanges 70 and 71, and engagement teeth are formed on the entire periphery of the lower flanges 70 and 71. Then, the reel 62,
63 is urged toward the lower half 61 by leaf springs 51 and 52. The magnetic tape is provided at the front (left side in FIG. 3) of the cassette and at the left and right tape guides 65, 65.
The lower half 61 passes through an opening 67 on the front side of the lower half 61.

[0004] An upper half 75 as the other half forming a cassette case together with the lower half 61 includes:
A lid 69 that covers the magnetic tape passing through the opening 67 at the front end of the cassette is attached to be openable and closable. The lid 69 includes three members, an outer lid 76, a top lid 77, and an inner lid 78.

A lock pin 80 protrudes from the inside of the side plate 79 of the outer lid 76. A lid lock 82 that locks the lock pin 80 and locks the lid 69 in the closing direction of the opening 67 is rotatably attached to the side plate portion 87 of the lower half 61. Further, a lid lock spring 83 that biases the lid lock 82 in the closing direction of the lid 69 is provided on the rear side of the cassette of the lid lock 82.

[0006] As shown in FIG.
A ring portion 83b is formed at one end of a wire spring 83a, a ring portion 83b is mounted on a mounting pin 84a of a cylindrical boss 84 formed on the lower half 61, and an intermediate portion of the free end of the wire spring 83 is a side wall. The lower half 6 is engaged with a guide groove 87a formed at an upper end of a guide member 87 provided at a part of the lower half 6.
1 and urges the lid lock 82 in the lock direction A. In addition, the mounting pin 84a has a sufficient height that the wire spring 83a can take a temporary engagement until the upper half 75 is put on the lower half 61 by taking such an engaged state.

When the upper half 75 is put on the lower half 61, the guide groove 72a of the guide member 72 protruding from the inner wall surface of the upper half 75 is provided on the cylindrical boss 84 and the guide provided on a part of the side wall. Wire spring 83 bridged with member 87
The wire spring 83a is engaged with the middle portion of the wire spring 83a from above to position the wire spring 83a. Therefore, the free end of the wire spring 83a is engaged with the lid lock 82 from the upper half 75 side (upper side) to urge the wire spring 83a to the closed state.

Then, with the lid lock 82 mounted on the lower half, the upper half 75 is assembled from above the lower half 61, and then, the cassette case is turned over and the lower half 61 is turned upward. The screw 90 shown in FIG. 3 is tightened with a screwdriver or the like to complete the assembly.

[0009]

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 half 61 is slightly floating from the upper half 75 due to the urging force of the leaf spring 51, and there is a slight gap. Here, the ring portion 83 of the lid lock spring 83
It is sufficient that b is tightly fitted to the mounting pin 84a, but the ring portion 83b may be in a loosely fitted state with the mounting pin 84a due to an error at the time of manufacturing or the like. In this case, if the winding height of the ring portion 83b of the lid lock spring 83 is small, there is a problem that the ring portion 83b comes off the mounting pin 84a or the wire spring 83a rotates about the mounting pin 84a due to vibration or the like. .

The two guide grooves 72a and 87a are slightly different in position along the direction in which the wire spring extends.
In the state where 1 is floating from the upper half 75, the guide grooves 72a, 8
A horizontal gap is formed between 7a. Accordingly, the wire spring 83a rotates due to vibration or the like, and the guide grooves 72a, 87
Once separated from a, when the upper and lower halves 61 and 75 are to be tightened with screws, the wire spring 83a cannot return into the guide grooves 72a and 87a, and cannot be properly assembled.

Further, even after the cassette is assembled, the wire spring 83a causes the guide groove 72 to move due to 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. SUMMARY OF THE INVENTION 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 a magnetic tape cassette.

[0012]

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 the 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 which engages with a lid lock and urges it to a closed state, the one end of the lid lock spring is attached to a mounting pin formed on a bottom wall of the lower half. Comprising an elongated coil portion to be inserted,
The winding height of the coil portion is set to be larger than a half gap formed at the time of assembling the upper and lower halves, and the coil portion has the mounting pin of the lower half and a side wall of the lower half facing the mounting pin. The magnetic tape cassette is characterized in that the magnetic tape cassette is held by a spring fixing rib provided in the gap.

According to the magnetic tape cassette of the present invention, when the upper half is assembled to the lower half, and the cassette case is turned upside down and the lower half is screwed up with the lower half facing upward, the lower half is attached to the lower half by a leaf spring. Even if a gap is generated between the side walls of the upper and lower halves under the influence of the force, since the winding height of the coil section is longer than the gap, the lid lock spring is disengaged from the gap. There is no. A fixing rib is provided in a gap between the lower half mounting pin and the lower half side wall facing the mounting pin, so that the coil portion is securely held by the mounting pin. It does not rotate. Therefore, the upper and lower halves are properly tightened by the screw to assemble the magnetic tape cassette, thereby improving the assemblability. In addition, the lid lock spring does not come off from the mounting portion due to the impact when the cassette is dropped after assembly, so that a highly reliable lid lock can be guaranteed.

[0014]

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 will be described using the same reference numerals. FIG. 1 is an exploded perspective view of the vicinity of a lid lock before assembling upper and lower halves of a magnetic tape cassette according to an embodiment of the present invention, and FIG.
FIG. 5 is a partial cross-sectional view near the lid lock after the upper and lower halves are assembled.

As shown in FIG. 1, the lid lock 82 has a notch 61 formed on a side wall of a guide member 87 of the lower half 61.
The shaft 82a is supported by a and swingably mounted. A spring insertion rib 118 is provided on the side wall of the prismatic mounting pin 116 provided on the bottom wall of the lower half 61 to contact an inner peripheral surface of a lid lock spring described later. A divergent spring fixing rib 120 is formed in a gap between the side wall of the guide member 87 and the mounting pin 116. The distance S between the lower end portion of the spring fixing rib 120 and the mounting pin 116 is substantially equal to the wire diameter forming the lid lock spring. In this embodiment, the mounting pin 116 is formed from the bottom wall of the lower half 61, but a configuration in which a boss is formed on the bottom wall and the mounting pin is formed thereon may be used.

The lid lock spring 110 comprises a long wire spring 112 and a coil spring-like ring portion 114. The free end of the wire spring 112 abuts a projection 82c in a vertical slit 82b formed in the lid lock 82 to urge the lid lock 82 in the locking direction A. 116 is inserted. Since the winding height of the ring portion 114 is set to be larger than the gap between the upper and lower halves formed at the time of assembling the upper and lower halves, it does not come off from this gap.

Next, a method of assembling the above-described magnetic tape cassette will be described (see FIG. 3). First, lower half 6
After the reel and other various components are stored in the guide lock 1, the shaft portion 82 a of the lid lock 82 is swingably mounted in the notch 61 a of the guide member 87.
Ring portion 114 is inserted into the mounting pin 116. At this time, the inner peripheral surface of the ring portion 114 is
Since it is inserted while abutting on the upper part, the assembling work becomes easy. Since the lower end portion of the ring portion 114 is engaged with the gap between the lower end portion of the spring fixing rib 120 and the mounting pin 116, the lid lock spring 110 does not easily come off from the mounting pin 116. Further, the tip of the wire spring 112 of the lid lock spring 110 abuts on the projection 82c in the slit 82b of the lid lock 82 to urge the lid lock 82 in the locking direction A, so that the lid 69
Lock to closed state.

Next, the upper half 7 with the lid 69 assembled
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, a biasing force is applied to the lower half 61 by the leaf springs 51 and 52 attached to the upper half 75, and the lower half 61 floats and a slight minute gap is formed between the side wall of the upper half 75 and the side wall of the lower half 61. Occurs. However, the winding height of the ring portion 114 of the lid lock spring 110 is not
It is set such that even if at least one of the first and the first 75 is warped and a larger gap is generated, it does not easily come off the mounting pin 116. Therefore, the lid lock spring 1
10 does not fall out of the gap.

Guide members 72, 8 of upper and lower halves 75, 61
In 7, the guide grooves 72 a and 87 a are opposed to the wire spring 112, and the position of the wire spring 112 in the horizontal direction is substantially regulated by accommodating the wire spring 112 in the guide grooves 72 a and 87 a. When the upper and lower halves 75 and 61 are combined and tightened with the screw 90, the position of the wire spring 112 in the vertical direction is also substantially regulated.

Therefore, when the upper and lower halves 75 and 61 are reversed when the upper and lower halves 75 and 61 are tightened with the screw 90, a gap is formed between the side walls of the upper and lower halves 75 and 61 by the action of the leaf springs 51 and 52. Toki Wire Spring 1
Even if a force in the rotational direction acts on the lid lock spring 1,
The ten wire springs 112 are held at appropriate positions without being separated from the guide grooves 72a and 87a. That is, even if the upper and lower halves 75 and 61 are inverted during the assembly of the cassette, the lid lock spring 110 does not come off from the mounting portion, so that the assembling workability is improved.

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 configured to regulate the position of a wire spring by upper and lower halves.

[0022]

As described above, according to the magnetic tape cassette of the present invention, one end of the lid lock spring is provided with the elongated coil portion which is inserted into the mounting pin formed on the bottom wall of the lower half. The winding height of the coil portion is set to be larger than a half gap formed when assembling the upper and lower halves, and the coil portion is provided in a gap between a mounting pin of the lower half and a side wall of the lower half facing the mounting pin. Held by the provided spring fixing ribs. Therefore, even if a gap is formed between the side walls of the upper and lower halves due to the urging force applied to the lower half by the leaf spring, the lid lock spring does not come off from the gap. Also, since the coil portion is securely held by the mounting pin, the lid lock spring does not rotate around the mounting pin, the upper and lower halves are properly tightened with screws, and the magnetic tape cassette is assembled, The assemblability is improved. In addition, the lid lock spring does not come off from the mounting portion due to the impact when the cassette is dropped after assembly, and a highly reliable magnetic tape cassette can be obtained.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a main part near a lid lock of a magnetic tape cassette according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing an assembled state in FIG.

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

FIG. 4 is an exploded perspective view of the vicinity of a lid lock in FIG. 3;

[Explanation of symbols]

 51, 52 leaf spring 61 lower half 72a, 87a guide groove 75 upper half 82 lid lock 82a shaft portion 82b slit 82c protrusion 87 guide member 110 lid lock spring 112 wire spring 114 ring portion 116 mounting pin 118 spring insertion rib

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 be in a closed state. A biasing magnetic tape cassette, wherein the one end of the lid lock spring has an elongated coil portion which is inserted into a mounting pin formed on a bottom wall of the lower half. The winding height of the coil portion is set to be larger than a half gap formed at the time of assembling the upper and lower halves, and the coil portion has the mounting pin of the lower half and a side wall of the lower half facing the mounting pin. The magnetic tape cassette is held by a spring fixing rib provided in a gap of the magnetic tape cassette.