JPH0445185Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a tape cassette equipped with a slide cover, which is characterized by the shape of the spring for returning the slide cover.

[Prior Art] A conventional tape cassette with a slide cover has a cassette body which is a combination of an upper half 1 and a lower half 2, and a cassette body which can be opened and closed, as shown in FIGS. 7 and 8, for example. Installed front cover 3
and a slide cover 4 that is slidably attached to the lower half 2 in the direction of arrow O.

When this tape cassette is stored, the front cover 3 is in a closed state as shown in Fig. 7, and the slide cover 4 is also in the forward position (closed state) to prevent the tape from getting dirty. There is.

On the other hand, when this tape cassette is loaded onto a deck, a mechanism provided on the deck rotates the front cover 3 and moves the slide cover 4 backward, both of which are in an open state. In other words, it becomes as shown in FIG.

Furthermore, when the tape cassette is removed from the deck, the front cover 3 rotates and the slide cover 4
move forward and return to the closed state, that is, the state shown in FIG. This movement of the slide cover 4 from the open state to the closed state is automatically performed by the action of a return spring provided within the cassette.

Among these automatic return operations, automatic return of the slide cover 4 is performed by a slide cover return spring 10' shown in FIG. That is, a figure-eight-shaped slide cover return spring 10' is disposed between a spring arrangement wall 5 provided on the lower half 2 and an abutment wall 6 provided at the end of the slide cover 4. This slide cover return spring 10'
The slide cover 4 is always pressed forward by the repulsive force. Therefore, during storage, etc., the slide cover 4 is always in a closed state.
Also, when loading the tape cassette onto the deck as described above, push the slide cover 4 backwards and release the spring 1.
The slide cover 4 is moved back against the force of 0' to open it. Further, when the tape cassette is removed from the deck, the slide cover 4 is moved forward by the repulsive force of the spring 10' and is automatically closed.

As described above, this slide cover return spring 10' is, for example, a plate spring formed into a figure-eight shape, and both ends of which are bent outward to form leg portions 10'a.

As shown in FIG. 9, the conventional slide cover return spring 10' having such a shape lowers the leg portion 10'a as the slide cover 4 approaches the open state.
The whole comes into contact with the abutment wall 6. the result,
The effective length of the spring-acting portion of the leaf spring 10' is reduced, and the repulsive force F of the leaf spring 10' becomes too strong, resulting in the maximum value Fmax of the return force of the slide cover 4.
It exceeds. In other words, the repulsive force F by the spring 10' against the moving amount L of the slide cover 4 in this conventional example is as shown in FIG. Although it increases little by little, the amount of movement L ₁
It increases rapidly from around , and exceeds the maximum repulsive force Fmax at the open stop position (Lmax).

The repulsive force of the return spring is preferably an appropriate value within a certain range within the sliding range of the slide cover for the following reason, and is not preferable if it is too strong or too weak.

That is, the slide cover 4 inserts the lower half 2 into the insertion hole 8 (see FIG. 7) provided in the slide cover 4.
A locking pawl (not shown) formed with spring properties is inserted and locked to maintain the open state. Therefore, if the return force by the return spring 10' is too strong, the locking pawl will deteriorate, making it impossible to maintain the open state. Furthermore, if the return force of the spring 10' is too strong, loading of the cassettes into the deck will not be carried out smoothly because loading will be carried out against this force.

On the other hand, if the repulsive force of the return spring 10' is too weak, the slide cover will not return to the completely closed state when the cassette is removed from the deck.

[Problem that the invention attempts to solve]

The problem to be solved by the present invention is to provide a tape cassette having a slide cover configured such that the repulsive force of the slide cover return spring is always within an appropriate range.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides a biasing member for returning the slide cover, such as a leg of a figure-eight spring, with a semicircular protrusion that protrudes inward. It is something that

According to this, even when the slide cover is in the most open state (opening stop position), the leg portion of the spring contacts the abutment wall only by the protrusion, and the entire leg portion does not come into contact with the abutment wall. Therefore, regardless of the position of the slide cover, the portion that contributes to the spring's repulsive force is substantially the same, and as a result, the spring's repulsive force (slide cover's return force) does not increase rapidly. do not have. In other words, sufficient return force can be obtained even in the weakest force state near the closed stop position when the slide cover is completely closed, and conversely, even in the strongest state of the open stop position, the maximum repulsive force Fmax cannot be exceeded. It is easy to avoid this.

〔Example〕

Next, a first embodiment of the tape cassette of the present invention will be described.
This will be explained based on FIGS. 6 to 6.

FIG. 1 is an exploded perspective view of one embodiment of the present invention.
is an upper half, 2 is a lower half, 3 is a front cover, 4 is a slide cover, 5 is a wall for arranging a spring for returning the slide cover, 6 is an abutment wall for the return spring provided on the front side of the slide cover 4, 7 is a closing stop hole for stopping the slide cover 4 in the closed state;
8 is an opening stop hole for stopping the same in the open state;
Reference numeral 9 denotes a fitting claw provided on the lower half 2, all of which are substantially the same as in the conventional example shown in FIGS. 7 to 9 (the fitting claw 9 is not shown in the conventional example). Further, 11 is a reel stopper, and 12 is a spring for pressing the reel stopper, which are also provided in the conventional example.

In this embodiment, the slide cover return spring 10
The shape is different from the conventional one, as shown in detail in FIG. That is, semicircular protrusions 10b are formed at the tips of the leg portions 10a of the figure-eight-shaped leaf spring 10 so as to face each other and protrude inward. As a result, the slide cover return spring 10 is activated at approximately one point between the contact wall 6 and the tip of the leg portion 10a, whether the slide cover 4 is in the open state shown in FIG. 2 or in the closed state shown in FIG. We will meet at As a result, as shown in FIG. 5, the repulsive force F of the slide cover return spring 10 changes linearly and slightly increases at a constant rate with respect to changes in the amount of movement L of the slide cover. Therefore, even when the amount of movement of the slide cover in the open state shown in Fig. 2 is Lmax, the repulsive force is at its maximum value.
Fmax will not be exceeded.

FIG. 6 is a diagram showing a second embodiment of the slide cover return spring. The spring 13 of this embodiment is a torsion coil spring, and has protrusions 13b similar to those of the first embodiment at the tips of its legs 13a.

Also in this second embodiment, the slide cover 4
In all states from the open state to the closed state, the leg portion 13a of the slide cover return spring 13 and the contact wall 6 are in contact with each other at almost one point, so that the spring repulses against the movement amount L of the slide cover 4. The change in force F is as shown in FIG. 5, and even when the slide cover 4 is in the open state (at Lmax), the repulsive force F does not exceed the maximum repulsive force Fmax.

As described above, in both embodiments, the repulsive force of the slide cover return springs 10, 13 does not exceed Fmax, so that the drawbacks of the conventional example do not occur. Note that the protrusions 10 of the leg portions 10a, 13a of the slide cover return springs 10, 13 mentioned above
b, 13b are not limited to semicircular shapes, but may be U-shaped, V-shaped, etc.

[Effect of idea]

The tape cassette of the present invention has a shape in which a protrusion is provided on the leg of the spring for returning the slide cover.
The repulsive force of the spring does not increase rapidly near the open position of the slide cover, so even if the slide cover is opened and the spring deformation is maximized, the return force remains within an appropriate range ( Fmax or below), and has the advantage that the return spring can be easily designed. In addition, the tape cassette can be loaded onto the deck smoothly, and
To smoothly and reliably return a slide cover when it is removed from a deck. Furthermore, there is no reduction in deterrent force or damage due to deterioration of the stopper claw provided on the lower half, and the stopper in the open state is reliable.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing the first embodiment of the tape cassette of the present invention, FIGS. 2 and 3 are cross-sectional views showing the open and closed positions of the slide cover in the first embodiment, 4 is a perspective view of the slide cover return spring used in the first embodiment, FIG. 5 is an explanatory diagram showing changes in return force with respect to the slide cover movement amount in the first embodiment, and FIG.
The figure is a perspective view of the slide cover return spring used in the second embodiment of the present invention, and FIGS. 7 and 8 are perspective views showing a conventional tape cassette with the slide cover in the closed and stopped positions, respectively. ,
FIG. 9 is a sectional view of a conventional tape cassette with the slide cover in the open and stopped position, and FIG. 10 is an explanatory diagram of the conventional tape cassette showing changes in return force with respect to the amount of movement of the slide cover. 1...Upper half, 2...Lower half, 3...Front cover, 4...Slide cover, 5...Slide cover return spring arrangement wall, 6...Abutting wall, 7...
Closing stop hole, 8... Opening stop hole, 9... Fitting claw, 10, 13... Slide cover return spring.

Claims (1)

[Scope of utility model registration request] A dustproof device with a front cover that is rotatably attached to the cassette body for opening and closing, and a contact wall that is vertically raised on the front side of the front cover and that is slidable back and forth along the bottom of the body. and a biasing member that biases the slide cover in the closing direction, and the biasing member is a figure-of-eight spring whose intermediate bent portion is supported by the main body, and whose legs at both ends are attached to the slide cover. The tape cassette is arranged so as to be in contact with the abutting wall of the cassette, and the abutting wall has a length that covers most of the tape located at the front inside the cassette body, and both legs are in the most open state. The structure is configured such that it comes into contact with the abutment wall even when the legs are in contact with each other, and has semicircular protrusions that protrude toward the sides that come into contact with the legs, so that even when the legs are widest apart, the intermediate portions of the legs do not come into contact with each other. A tape cassette characterized in that it is configured to be separated from a contact wall.