JPS6253Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cassette front lid unlocking device provided for protecting cassette tapes.

The front cover of the cassette (referred to as the front cover) always closes the front opening so that the tape is not exposed through the front cover opening of the cassette when not in use, and is locked in the closed state.

The lock is released only when the cassette is inserted into the video tape recorder (VTR), and the automatic opening/closing mechanism of the front lid opens the front opening of the front lid to expose the tape surface.

The present invention relates to an improvement of such a front cover unlocking device, and aims to provide a mechanism that helps prevent damage to the cassette and the unlocking member when the cassette is attached or detached.

First, one embodiment of a front cover locking device provided on a cassette will be described with reference to FIGS. 1 to 3.

FIG. 1 is an exploded perspective view of the locking device, FIG. 2 is a perspective view of essential parts of the front cover, and FIGS. 3a and 3b are cross-sectional views illustrating the operation of the same. In addition, in FIG. 1, a leaf spring for unlocking is also shown.

The front end of the cassette 1 is provided with a storage part 3' in which the lock piece 3 is stored, and curved parts 17 and 1 on which the rotation pins 7 and 10 of the lock piece 3 are placed, respectively.
8 is formed, and furthermore, holes 14 and 15 are formed through which the lock pin 5 and the lock release pin 6, which are integrally provided on the lock piece 3, pass through. Further, a recess 16 is formed at the front end, on which the rotation pin 11 of the front lid 2 is placed.

Therefore, the rotation pins 7 and 1 are attached to the curved portions 17 and 18.
0 is mounted and is rotatable, and the lock piece 3 is stored in the storage part 3', and both ends of the helical spring 8 inserted into the spring mounting pin 9 of the lock piece 3 are connected to the storage part 3' and the lock piece. 3, the locking piece 3 is elastically biased by the helical spring 8 so that the locking pin 5 and the lock release pin 6 protrude outward from the holes 14 and 15.

The front cover 2 is rotatable with a rotation pin 11 placed in a recess 16, and is appropriately biased by a spring to open the front opening of the cassette 1. When the opening is rotated to the position where the opening is closed, the locking protrusion 13 engages with the locking pin 5 protruding from the hole 14 as described above, as shown in FIG. is locked.

In this locked state, the lock release pin 6 protrudes outward from the hole 15 as shown in FIG. When pushed in, the locking pin 5 disengages from the locking protrusion 13 as shown in FIG. develop.

In addition, the small protrusion 12 provided on the rotation pin 11 in FIG.
It prevents the front cover from falling off in the lateral direction and serves as a point of action for a spring that always biases the front cover in the direction of closing.

The cassette holder into which the cassette 1 having the front lid 2 as described above is inserted has a regulating piece such as a lock release spring 4 so that the lock release pin 6 can be pushed into the cassette holder.
An embodiment of the present invention in this case will be described in detail below.

Figures 4a and 4b are side views and A-A sectional views of essential parts of an embodiment of the lock release device of the present invention, and Figures 5a and b and Figures 6a and b illustrate the principle of the same operation. A side view and a cross-sectional view are shown, respectively.

A cassette holder (not shown) has a side wall member 19 fixedly disposed on the side wall facing the lock release pin 6 of the cassette to be inserted.

The outer surface of this side wall member 19 facing the side wall (the side opposite to the internal space of the cassette holder)
The guide pins 21 and 21' are implanted at a predetermined interval in the insertion direction of the cassette.
The long holes 20, 20' drilled at both ends of the lock release spring 4 are fitted into the lock release spring 4, and there is a gap corresponding to the lock release spring 4 between the side wall member 19 and the side wall of the cassette holder. The lock release spring 4 is configured to move forward and backward relative to the guide pins 21 and 21' along the elongated holes 20 and 20', that is, in the direction of insertion and movement of the cassette.

A through hole 19' is formed in the center of the side wall member 19, and the lock release spring 4 has a substantially dogleg shape, and the apex portion 4' of the dogleg shape is inserted through the through hole 19' into the cassette receiver. It juts out into the internal space of the stand.

Therefore, when the cassette is inserted into the cassette cradle, when the apex 4' comes into contact with the cassette and is pushed backward, the lock release spring 4 moves rearward, and when the cassette is removed from the cassette cradle, the cassette When the apex portion 4' is pushed forward, the lock release spring 4 moves forward.

Here, the long holes 20, 20' and the guide pin 2
1 and 21' are arranged in the following relationship. That is,
When the lock release spring 4 moves backward as in the former case, the front edge of the elongated hole 20' first comes into contact with the pin 21' to prevent further movement, and as in the latter case, the lock release spring 4 moves forward. When it retreats, the rear end edge of the elongated hole 20 first comes into contact with the pin 21, preventing further retreat.

The operation of the above embodiment of the present invention will be explained with reference to FIGS. 5 and 6.

When the cassette is inserted into the cassette holder and moves rearward, that is, in the direction of arrow _A1 , the apex portion 4' comes into contact with the cassette, and the lock release spring 4' moves rearward together with the cassette. The front edge of the lock release spring 4 hits the pin 21', so that a force is applied to the lock release spring 4 to rotate it in the direction of arrow _B1 with the pin 21' as a fulcrum. That is, the lock release spring 4 is pushed away from the cassette against its elastic force, resulting in the state shown in FIGS. 5a and 5b.
Note that the front end edge of the elongated hole 20 is prevented from coming into contact with the pin 21.

In this way, the lock release spring 4 can be pushed away without interfering with the movement of the cassette.

However, if the front edge of the elongated hole 20 hits the pin 21 first, the lock release spring 4
Since a force acts in the direction of arrow _C1 , a large force is required to push the lock release spring 4 away from the cassette, which may cause the cassette to get caught or damage the lock release spring 4 when the cassette is inserted. There is a possibility that this is a problem.

At a predetermined position such as the loading position, the apex portion 4' releases the lock release pin 6.
The front cover 2 is opened by pressing .

When the cassette is pulled out from the cassette holder and moves in the direction of arrow _A2 , the pressure on the lock release pin 6 by the apex portion 4' is released, the front cover 2 is closed, and the cassette, for example, the apex portion 4' is removed by the front cover. When pushed, the lock release spring 4 retreats forward together with the cassette, and first the rear end edge of the elongated hole 20 comes into contact with the pin 21. As a result, the lock release spring 4 is
With 1 as a fulcrum, a force is applied in _{the 2} directions of arrow B and the object is pushed away from the cassette. thus,
The lock release spring 4 can be pushed away in a direction where it does not interfere with the movement of the cassette. At this time, it is assumed that the rear end edge of the elongated hole 20 does not come into contact with the pin 21'.

However, if the rear edge of the elongated hole 20' hits the pin 21' first, the lock release spring 4
A force is applied in the _two directions of arrow C, and there is a risk that the tape will get caught on the front cover 2 and open it, exposing the tape and possibly causing damage to the tape.

In this way, the lock release spring can move with the cassette when pushed, and can be pulled away from the cassette, thereby preventing damage to the cassette or the lock release spring, and further simplifying operation. You can also do it.

According to the lock release device for the cassette front cover of the present invention, it is possible to prevent damage to the cassette or the release piece and to improve operability as described above, and the lock release device can be improved by preventing damage to the cassette or the release piece and improving operability. It is possible to have a simple configuration.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view of the locking device for the cassette front cover, Fig. 2 is a perspective view of the main parts of the front cover, Figs. Figures a and b are a side view and a sectional view taken along line A-A of an embodiment of the cassette front cover lock release device of the present invention, and Figures 5 a and b and Figures 6 a and b illustrate the principle of the same operation. A side view and a cross-sectional view are shown, respectively. 1: Cassette, 2: Front cover, 6: Lock release pin, 4: Lock release spring, 19: Side wall member, 20
and 20': long hole, 21 and 21': pin.

Claims (1)

[Scope of Claim for Utility Model Registration] The cassette holder is designed so that when the cassette to be inserted reaches a predetermined position, the front lid lock pin of the cassette is pressed to unlock the front lid and open the front lid. In the case of a lock release device having a release piece for controlling the lock, the release piece is composed of an elastic strip whose central part projects inward of the cassette holder so as to be able to press the front cover lock pin, and at its front and rear ends. A lock release device for a cassette front lid, characterized in that the strip has elongated holes long in the longitudinal direction of the strip, each of which is loosely fitted into a pin installed in the cassette holder.