JPH0514382Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to magnetic tape cassettes used in VTRs (video tape recorders), etc.
This invention relates to the mounting structure of the front cover that is mounted on the front of the cassette main body which is the VTR insertion side.

[Conventional technology]

Figures 4 to 6 show conventional magnetic tape cassettes used in household VCRs, with Figure 4 being a partially cutaway rear view of the magnetic tape cassette seen from the lower half side, and Figure 5 being a rear view of the magnetic tape cassette seen from the lower half side. 4 is a sectional view taken along line V-V in FIG. 4, and FIG. 6 is a partial view of the lower half corner corresponding to the notch in FIG. 4.

The magnetic tape cassette 1 has a cassette body 4 composed of an upper half 2 and a lower half 3, and a supply reel 6 on which a magnetic tape 5 is wound within the cassette body 4.
A pair of take-up reels 6 and 7 are housed in the front part of the cassette main body 4, which is the side where the VTR is inserted. A front cover 8 is attached to cover the magnetic tape 5 running on the magnetic tape 5 in an openable and closable manner.

This front lid 8 is formed in a U-shape in plan with side plates 8c, 8c extending on both sides of a front plate 8a and a top plate 8b.
A rotation support shaft 9 protruding from the inside of the side plates 8c, 8c.
10 is attached to the mounting recess 2b bored in the front side of the side walls 2a, 2a of the upper half 2, and the front cover 8 is attached to the long pivot shaft 9 to keep the front cover 8 closed. A helical spring 11 is locked.

At the corner of the lower half 3 corresponding to the spring 11, a front lid locking member 12 is attached to the support shafts 12 on both sides of the upper part.
a, 12a are rotatably suspended from the ribs 3a, 3a of the lower half 3, and the front lid locking member 12 is supported by the biasing force of the front lid locking member spring 13 attached to one shaft 12a. Therefore, the locking protrusion 12b and the releasing protrusion 12c protrude outward from the side wall 3b of the lower half 3, and the locking protrusion 12b engages with the front cover 8 to hold the front cover 8 in the closed state. ing.

The spring 11 is formed by bending a spring wire, and has a coil portion 11a fitted onto the pivot shaft 9, and a locking pin 14 with a fixed end 11b protruding from the pivot shaft 9. The free arm portion 11c, which curves toward the inner surface of the upper half 2, is loosely fitted into the guide groove 15 formed on the inner surface of the upper half 2, and is attached to the front lid 8. , both halves 2,
3 are screwed together with screws 16 to form the cassette body 4, and then the cassette body 4 is normally biased in the closing direction by the biasing force of the spring 11.

[The problem that the idea attempts to solve]

However, in the above-mentioned device, when the front cover 8 is attached to the upper half 2 before the lower half 3 is attached to the upper half 2, the state of connection between the upper half 2 and the front cover 8 via the spring 11 becomes unstable. Therefore, the rotation support shaft 9 on which the spring 11 is mounted is likely to come off, requiring time and effort to reassemble it, and the spring may be lost during this process, resulting in poor workability.

Further, the front lid 8 is attached to the upper half 2 with a front lid locking member 1.
2 are respectively assembled to the lower half 3, but when the lower half 3 is attached to the upper half 2, the helical spring 11 that keeps the front lid 8 in the closed state and the spring 13 for the front lid locking member are assembled. Despite their proximity, they needed both.

The present invention was developed against the background of the above circumstances, and it not only improves assembly workability by ensuring attachment of the front cover to the lower half, but also connects the front cover and the front cover locking member with a single spring. It is an object of the present invention to provide a magnetic tape cassette that is reliably energized.

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention forms a cassette body for storing a magnetic tape with an upper half and a lower half, and a mounting recess formed on the side wall of the upper half is provided with an opening/closing mechanism for opening and closing the front part of the cassette body. Attach the pivot shaft of the front cover that can cover the front cover, and lock the fixed end of the spring that keeps the front cover closed to the pivot shaft, and connect the tip of the free end of this spring to the inner surface of the upper half. In the magnetic tape cassette pressed against the
The spring is a plate spring, and has a curved portion that bulges toward the lower half between the fixed end and the tip of the spring, and this curved portion is pressed against the protruding piece of the front lid locking member. Constantly biases the front cover in the direction of locking it,
Further, a stopper protrusion is formed on the inner surface of the upper half to abut the tip of the spring and press the pivot shaft into the mounting recess when the front cover is rotated to the closed position. It is something to do.

[Effect]

With the above configuration, the tip of the spring that comes into contact with the stopper protrusion is held down without wobbling, so that the pivot shaft of the front cover that locks the fixed end is moved above the cassette body through the biasing force of the spring. The front lid is pressed and held in the mounting recess of the half, preventing the front lid from falling off from the upper half, and the biasing force of the curved portion of the spring against the protruding piece of the front lid locking member is stabilized, so that the front lid and the front lid are The locking member can be held securely with one spring.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

The spring 18, which is locked to the pivot shaft 17 of the front lid 8 and keeps the front lid 8 in the closed state, is connected to the lower half 3 side, which connects the fixed end 18a, the free end side tip 18b, and both ends 18a, 18b. The spring 18 has a curved portion 18c that bulges out, and is formed from a plate spring. The tip 18b of the free end is inserted through the axial slit 19 and is attached with the curved portion 18c bulging toward the lower half 3 side, and is guided by the guide groove 20 formed on the inner surface of the upper half 2 on the left and right sides. It comes into contact with a stopper protrusion 21 formed at the front of the groove 20 and is supported by the upper half 2 under pressure.

The front lid 8 is then assembled to the upper half 2 by mounting the rotation support shaft 17 equipped with the spring 18 together with the other rotation support shaft into the mounting recess 2b.

At the corner of the lower half 3 facing the attachment part of the spring 18, a front lid locking member 22 for locking the front lid is provided.
However, the support shafts 22a, 22a on both sides of the upper part are connected to the lower half 3.
It is rotatably suspended from the ribs 3a, 3a of
The front lid locking member 22 includes a rotating protrusion 22b that is pressed against the curved portion 18c of the spring 18 and pushed.
A locking protrusion 22c and a releasing protrusion 22d are provided which protrude outward from the side wall 3b of the lower half 3, and the front cover 8 is engaged with the locking protrusion 22c to maintain the closed state. The working claw pushes the release protrusion 22d to release the engaged state.

When the front cover 8 is in the closed state covering the front part of the cassette body 4, the spring 18 has its free end tip 18b in contact with the stopper protrusion 21 of the upper half 2, and the curved part 18c moves toward the lower half 3. When it expands, the curved portion 18c pushes the protrusion 22b of the front lid locking member 22, so that the locking protrusion 22c protruding outside engages with the front lid 8, and the tip abuts against the stopper protrusion 21. Due to the reaction force of 18b, the pivot shaft 17 that locks the fixed end 18a is locked in the corner of the mounting recess 2b without wobbling.

This embodiment is configured as described above,
Load the magnetic tape cassette 1 into the VTR and close the front cover 8.
When opened, the pivot shaft 17 that locks the spring 18 rotates clockwise in FIG. The tip 18b slides on the inner surface of the guide groove 20 of the upper half 2 and retreats toward the rotation shaft 17, and the tip 18
b is separated from the stopper protrusion 21 of the upper half 2.

Then, when the magnetic tape cassette 1 is removed from the VTR and the front cover 8 is released from the open engagement,
Curved portion 1 of spring 18 expanding toward lower half 3 side
Due to the restoring force of 8c, the rotation support shaft 17 is rotated counterclockwise in FIG.
b comes into contact with the stopper protrusion 21 again, and the front cover 8 is urged to the closed position.

As described above, in this embodiment, the pivot shaft 17 of the front cover 8 is attached to the corner of the mounting recess 2b of the upper half 2 before the lower half 3 is assembled, and the spring 18 that comes into contact with the stopper protrusion 21 Since the pressure is applied using a biasing force, the upper half 2 with the front cover 8 attached can be held securely when being transported or assembled with the lower half 3, thereby eliminating the need for reassembly or loss of the spring 18. This eliminates the risk of this, and improves assembly work efficiency.

Moreover, after the halves 2 and 3 are assembled, the spring 18 is fixed at the fixed end 1 which is locked to the rotation support shaft 17.
8a and the tip 18b on the free end side that comes into contact with the stopper protrusion 21 stabilizes the biasing force of the curved portion 18c toward the lower half 3 side, and the front lid locking member 22 pushed by the curved portion 18c 8 reliably biases in the closing direction, and the front lid 8 and the front lid locking member 22 can be reliably held with one spring.

Furthermore, locking protrusions 23 and 24 may be protrudingly provided on the opening side and the bottom of the mounting recess 2b so as to surround the corner where the rotation support shaft 17 is mounted.
4, it is possible to further prevent the rotation support shaft 17 from falling off.

[Effect of idea]

As explained above, the magnetic tape cassette of the present invention has a mounting recess formed in the side wall of the upper half.
A rotation support shaft for the front cover that covers the front of the cassette body so that it can be opened and closed is attached, a spring that keeps the front cover closed is formed of a leaf spring, and the fixed end of the spring is locked to the rotation support shaft. At the same time, a curved portion bulging toward the lower half side is formed between the fixed end and the tip of the free end,
This curved portion is pressed into contact with the projecting piece of the front lid locking member to constantly bias the front lid in the direction of locking the front lid, and when the front lid is rotated to the closed position, the tip of the spring Since a stopper protrusion is formed on the inner surface of the upper half to abut and press the rotation shaft into the mounting recess,
Before the lower half is assembled, the front lid's pivot shaft is pressed by the biasing force of the spring that comes into contact with the stopper projection at the corner of the mounting recess of the upper half, making it easy to transport the upper half with the front lid attached. The front cover can be reliably held on the upper half even when assembled with the upper half and the lower half, eliminating the need for reassembly and the risk of losing the spring, improving assembly work efficiency.

Furthermore, after both halves are assembled, the biasing force toward the lower half of the curved portion of the spring is stabilized by the fixed end that is locked to the pivot shaft and the free end that abuts the stopper protrusion. , the front lid locking member pushed at the curved portion reliably biases the front lid in the closing direction,
The front cover and the front cover locking member can be securely held with one spring.

Furthermore, since a leaf spring is used, the durability of opening and closing the front cover is superior to that of a helical spring.

[Brief explanation of the drawing]

Figures 1 to 3 show an embodiment of the present invention. Figure 1 is a sectional view taken along line I-I in Figure 2, and Figure 2 is a cross-sectional rear view of the main part of the upper half viewed from the inner side. 3 are cross-sectional side views of the same essential parts, FIGS. 4 to 6 show conventional examples, FIG. 4 is a partially cutaway rear view of the magnetic tape cassette seen from the lower half side, and FIG. The figure is a sectional view taken along the line V-V in FIG. 4, and FIG. 6 is a plan view of the lower half corner corresponding to the notch in the upper left corner of FIG. 4. 1... Magnetic tape cassette, 2... Upper half,
2b...Mounting recess, 3...Lower half, 4...Cassette body, 5...Magnetic tape, 6...Supply reel, 7...Take-up reel, 8...Front lid, 17...
Rotating shaft, 18... Spring that keeps the front cover 8 in the closed state, 18a... Fixed end, 18b... Tip, 18
c...Curved portion, 21...Stopper projection, 22...
Front lid locking member, 22b... protrusion, 22c... locking protrusion, 22d... releasing protrusion.

Claims (1)

[Scope of utility model registration request] The upper half 2 and the lower half 3 form a cassette body 4 that stores the magnetic tape 5, and a mounting recess 2b formed in the side wall of the upper half 2 is provided with a front lid that opens and closes the front of the cassette body 4. 8 rotation support shaft 17
The fixed end 18a of the spring 18 that keeps the front cover 8 in the closed state is locked to the pivot shaft 17, and the free end tip 18b of the spring 18 is attached to the pivot shaft 17.
In the magnetic tape cassette in which the spring 18 is pressed against the inner surface of the upper half 2, the spring 18 is a plate spring, and between the fixed end 18a and the tip 18b of the spring 18 is a curved portion 18c that bulges toward the lower half 3 side. The curved portion 18c presses against the projecting piece 22b of the front lid locking member 22 to constantly bias the front lid 8 in the locking direction, and when the front lid 8 is rotated to the closed position. In this case, the tip portion 18b of the spring 18
A magnetic tape cassette characterized in that a stopper protrusion 21 is formed on the inner surface of the upper half 2, the stopper protrusion 21 coming into contact with the rotation support shaft 17 and pressing the rotation support shaft 17 into the mounting recess 2b.