JPH0552593B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to improvements in cassettes, and more particularly to a cassette provided with a lid for opening and closing the front surface of the cassette.

Conventional structure and its problems In recent years, magnetic recording using tape cassettes has been trending towards higher performance and higher density, and it is necessary to prevent the tape from being exposed to the outside air or from being exposed to fingerprints. It's here. Therefore, it has been considered to put a lid on the front opening of the cassette, and this has already been done for video cassettes and the like. If such a device is to be applied to an audio cassette, it is desired that the structure be simpler and that it can be implemented at a lower cost.

The cassettes proposed by the present inventors so far will be explained below. FIG. 1 is a perspective view showing the opened and closed state of the cassette, where a shows the closed state and b shows the open state. FIG. 2 is a plan perspective view of the main part, and FIG. 3 is a side view.

In Figures 1 to 3, 1 is the cassette body;
2 is the opening on the front of the cassette, 3 is the cassette lid, 4
5 is a fitting hole for the rotation support shaft 4 provided on the cassette lid 3, and is formed on the side surface of the cassette body 1 in a substantially triangular shape that tapers toward the rear. . Reference numeral 6 denotes a spring hanging pin formed integrally with the cassette main body 1, and 7 a spring whose one end is hung on the cassette lid rotation support shaft 4, which always urges the cassette lid 3 backward. 8 is magnetic tape, 9
is a protective wall that protects the magnetic surface of the magnetic tape 8 from the spring 7. Reference numeral 10 denotes a virtual line indicating the maximum diameter of the magnetic tape 8 that can be wound into a cassette having such a structure, and 11 indicates a magnetic tape which does not have such a structure and can be wound into an audio cassette which is currently widely used. This is an imaginary line indicating the maximum diameter of 1.

The operation of the cassette constructed as above will be explained. First, in order to open the lid of the cassette in the closed state shown in FIG. 1a, the lower front edge of the lid 3 is pushed upward. Since the lid 3 is biased backward by the spring 7, the lid 3 rises along the front surface of the cassette opening, and when it rises more than half way, it rotates clockwise about the upper part of the front edge of the opening as a fulcrum. It fits tightly against the top of the cassette. When closing, move the cassette lid 3, which is in the state shown in Figure 1b, forward along the cassette body 1, and it will move in the opposite direction to the opening to close the opening, as shown in Figure 1a. The state will be as follows. Although the lid can be opened downward, when used in an actual device, the cassette can be used on both sides, and the lid 3 always opens upward in the device.

However, in the above configuration, the spring 7 that biases the pivot shaft 4 provided on the cassette lid 3 toward the rear of the cassette body 1 is constructed of a so-called tension spring and is housed inside the cassette, so that the surface of the magnetic tape 8 is Coupled with the need for a protective wall 9 to protect the tape and the need for the winding diameter of the spring 7 to be at least 2 mm, the available volume within the cassette is reduced and the maximum tape that can be wound into the cassette is reduced. The winding diameter was smaller than the current cassette half, making it difficult to ensure long-term recording and playback.

Purpose of the invention The present invention solves the above-mentioned conventional problems.
To provide a cassette with a lid that has an extremely simple structure and operates reliably without impairing the maximum allowable tape winding diameter.

Structure of the Invention The present invention comprises a cassette body, a U-shaped lid for opening and closing an opening of the cassette body, a pair of pivot shafts for the lid provided on the sides of the U-shaped lid, and a cassette body. a pair of substantially triangular fitting holes that taper toward the rear, into which the pivot shaft fits, and a biasing means for biasing the pivot shaft toward the rear of the cassette body; This is a cassette in which the biasing means is arranged symmetrically with respect to the center line in the thickness direction passing through the center of the rotation support shaft toward the rear of the cassette body, and the configuration is extremely simple without reducing the maximum tape winding diameter. This makes it possible to realize a cassette with a lid that operates reliably.

DESCRIPTION OF EMBODIMENTS FIG. 4 is a front perspective view showing a closed state of a cassette lid according to an embodiment of the present invention, and FIG. 5 is a side perspective view.

In FIGS. 4 and 5, 1 is the cassette body;
2 is the opening on the front of the cassette, 3 is the cassette lid, 4
5 is a pivot shaft provided on the side of the cassette lid 3;
is a fitting hole for the cassette lid rotation support shaft 4, which is formed on the side surface of the cassette body 1 in a substantially triangular shape that tapers toward the rear. Reference numeral 12 denotes a spring support block, which is formed in a convex shape on one side and has a pair of stiff springs 17a,
It has shafts 16a and 16b that support the cassette body 17b, and wall surfaces 13a and 13b that are formed in a convex shape and are in contact with the hard springs 17a and 17b, and the upper and lower sides are the cassette body 1.
It is sandwiched between. 16a and 16b are spring hanging shafts formed integrally with the spring support block 12; 17a and 17b are walls having one end pressed against the cassette lid rotation support shaft and the other end being formed integrally with the spring support block 12. A pair of so-called tight springs 13 are supported by a center line 14 in the thickness direction of the cassette body 1 passing through the center of the pivot shaft 4 and facing toward the rear of the cassette body 1.
It is disposed axially symmetrically with respect to the cassette half, always urges the cassette lid 3 backward, and is incorporated inside the cassette half. The springs 17a and 17b are connected to the spring support block 1.
Fitted into shafts 16a and 16b provided in 2,
Since one end is biased by the rotation support shaft 4, the shaft 16
17a is biased to rotate clockwise, and 17b is biased counterclockwise, with a and 16b as rotation centers. However, the other ends of the springs 17a, 17b are formed integrally with the spring support block 12, such as a wall surface 13a,
13b and are prevented from rotating, and are pressed and supported by the respective spring biasing forces. Reference numeral 8 indicates a magnetic tape, and reference numeral 11 indicates the maximum winding diameter of the magnetic tape wound within the cassette main body 1 in this configuration.

An example of the operation of the cassette of this embodiment constructed as described above will be explained with reference to FIGS. 6 and 7.
Each component numbered 1, 3, 4, and 5 in the figure is shown in Figure 1 and 5.
It is similar to that shown in the figure. Also, FIG. 6 shows forces F, F', and
7 shows how F'' works according to the position of the cassette lid 3, and FIG. The forces ₁ , ₂ , ₁ ' ₂ ', _{1''2 '} ' acting on the pivot shaft 4 provided are shown according to the position of each cassette lid 3.

As an example, using FIG. 7a, the cassette lid 3 is
Examining the state of the force when closing the opening 2 of the cassette body 1, one end of the springs 17a and 17b is in pressure contact with the rotation support shaft 4 of the cassette lid 3, so that the rotation support shaft 4 Forces ₁ and ₂ are applied to . Rotation support shaft 4 provided on the side of the cassette lid 3
Since it is restrained by the fitting hole 5 provided in the side surface of the cassette body 1, it is urged toward the rear of the cassette body 1 when it receives either ₁ or ₂ . This causes a force F equivalent to that in the example shown in FIG. 6a to be applied, and the movement of the cassette lid 3 to be the same as in the case shown in FIG. 2. This means that the position of the cassette lid 3 is different b,
The same applies to case c, and the movement of the lid 3 in this embodiment is the same as that of the cassette shown in FIG.

As described above, according to this embodiment, as a biasing means for biasing the pivot shaft of the lid body toward the rear of the cassette body,
By using a pair of tight springs, the volume occupied inside the cassette due to the winding diameter of the tension spring 7 can be reduced to the thickness of the tight springs 17a and 17b, making it possible to wind the wire inside the cassette. This makes it possible to set the maximum diameter of the tape to the same diameter 11 as the so-called current analog cassette, and it becomes possible to guarantee long-time recording and playback characteristics. Furthermore, by using a configuration that uses two stiff springs as the biasing means, it is generally possible to
Even when assembling a split cassette body, the spring support block 12 to which the tightening spring 17b is attached can be assembled into the lower cassette body, and the lid 3 and the tightening spring 17a can be assembled in this order to the upper cassette, further improving the ease of assembly. It is something that can be done.

In addition, tight springs 17a and 17b shown in FIG.
17a and 17b have a configuration in which the portions in contact with wall surfaces 13a and 13b formed integrally with the spring support block 12 are located below the portion in contact with the rotation support shaft 4, and 17a and 17b have different shapes on the left and right sides. They have different configurations.

On the other hand, the hard spring shown in FIG. 8a is the same as the hard spring 13a shown in FIG.
Even if 13a is used in place of 3b with the left and right sides reversed, the same effect can be obtained, and in addition, the effect that the present invention can be realized with one type of spring is added.

Needless to say, this also applies to the use of the stiff spring 13b in FIG. It is also possible to use an integrally configured stiff spring as shown in FIG. 8b, and in this case, the effect of reducing the number of parts can be seen. Also, the tight spring shown in Fig. 8c is α=
If used as β, the number of types of parts will be reduced and there will be no directionality during assembly, which will have the effect of improving workability. Furthermore, as shown in FIG. 8d, even if an elastic material such as a wire is used, the same effect can be obtained in opening and closing the lid, and the unit cost of parts can be significantly reduced.

In addition, in FIG. 8d, a pair of tight springs 17
Since the members other than a' and 17b' are the same as those in FIG. 5, the same reference numerals are used.

Effects of the Invention The present invention provides a cassette body, a U-shaped lid for opening and closing the opening of the cassette body, a pair of pivot shafts for the lid provided on the side surfaces of the U-shaped lid, and a pivot shaft provided on the cassette body. and a pair of substantially triangular fitting holes into which the rotation support shaft fits and taper toward the rear, and a line passing through the center of the rotation support shaft to the center line in the thickness direction toward the rear of the cassette body. By using biasing means arranged symmetrically and biasing the pivot shaft toward the rear of the cassette body, it is possible to create a cassette with a lid that has a simple structure without impairing the maximum permissible tape winding diameter. can be realized.

[Brief explanation of the drawing]

Figure 1 shows the opened and closed state of the cassette with a lid.
a is a perspective view of the closed state, b is a perspective view of the open state, the second
The figure is a plan perspective view of the main part, and Figure 3 is a side view.
FIG. 4 is a plan perspective view of the cassette in the closed state in an embodiment of the present invention, FIG. 5 is a side perspective view thereof, and FIG.
Figures a, b, and c are explanatory diagrams of the urging force of the cassette in Figure 2, Figures 7 a, b, and c are explanatory diagrams of the urging force of this embodiment, and Figures 8 a, b, c, and d are illustrations of other biasing forces. FIG. 3 is an enlarged view of main parts of the embodiment. 1...Cassette body, 2...Opening, 3...
Lid, 4... Lid rotation support shaft, 17a, 17b... Spring, 12... Spring support block.

Claims (1)

[Scope of Claims] 1. A cassette body having an opening on one side, a U-shaped lid for opening and closing the opening, and a pair of pivot shafts provided on the sides of the U-shaped lid. A pair of substantially triangular fitting holes which are provided in the cassette body and into which the pivot shaft fits and taper toward the rear, and a biasing means for biasing the pivot pivot cassette body rearward. Become,
A cassette characterized in that the biasing means is arranged symmetrically with respect to a center line in the thickness direction passing through the center of the pivot shaft and extending toward the rear of the cassette body. 2. The cassette according to claim 1, characterized in that the urging means is integrally constructed.