JPH0573761U - Tape cassette - Google Patents

Abstract

(57) [Summary] [Object] To provide a tape cassette in which a pair of 45-degree reflecting surfaces can be easily integrally formed with the upper half and the lower half of the cassette body. [Structure] A pair of 45-degree reflecting surfaces for returning the light incident from a tape end sensor for detecting the tape end of the magnetic tape to the sensor inside a cassette body composed of an upper half and a lower half for housing the magnetic tape. In the provided tape cassette, one of the pair of the 45-degree reflecting surfaces is formed on the upper protrusion integrally formed on the upper half, and the other is formed on the lower protrusion integrally formed on the lower half. Characterize.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a tape cassette, and more particularly to a tape cassette in which a pair of 45-degree reflecting surfaces can be easily integrally formed with the upper half and the lower half of the cassette body.

[0002]

[Prior Art]

 In a general tape cassette, the light emitted from the light emitting part of the tape end sensor equipped in the tape cassette drive toward the inside of the cassette body is reflected by the prism provided inside the cassette body, and the reflected light is The tape end sensor is configured to send back the light toward the light receiving portion, and the magnetic tape housed in the cassette body blocks the reflected light. The reflected light is transmitted through the transparent leader tape connected to the tape end of the magnetic tape, so that the tape end sensor detects the tape end of the magnetic tape.

Further, in the tape cassette as described above, the prism 9 is provided with a pair of 45-degree reflecting surfaces 91 and 92 as shown in FIG. 4, and is integrally formed on the upper half 2 of the cassette body 1. Has been done.

[0004]

[Problems to be solved by the device]

 However, in the above-described tape cassette, the prism 9 is undercut between the one 45-degree reflecting surface 91 and the upper half 2 (A portion), as shown in FIG. When integrally molding with the upper half 2, as shown in FIG. 5, in addition to the upper mold 11a and the lower mold 11b, a slide piece (mold) 10 or the like has to be used, so that the cost required for manufacturing the tape cassette is And labor will increase.

Therefore, an object of the present invention is to provide a tape cassette in which a pair of 45-degree reflecting surfaces can be easily integrally formed with the upper half and the lower half of the cassette body.

[0006]

[Means for Solving the Problems]

 According to the present invention, a pair of 45-degree reflecting surfaces for returning light incident from a tape end sensor for detecting the tape end of the magnetic tape to a cassette main body including an upper half and a lower half for accommodating the magnetic tape. In the tape cassette provided with, one of a pair of the 45-degree reflecting surfaces is formed on an upper protrusion integrally formed on the upper half, and the other is formed on a lower protrusion integrally formed on the lower half. The above object is achieved by providing a tape cassette characterized by the following.

[0007]

[Action]

 According to the tape cassette of the present invention, the light incident from the light emitting part of the tape end sensor into the cassette body is integrally molded with the lower half by the 45 ° reflection surface at the tip of the upper protrusion integrally molded with the upper half. The reflected light is sequentially reflected by the 45-degree reflecting surface at the tip of the lower projection thus formed, and sent back toward the light receiving portion of the tape end sensor.

[0008]

【Example】

 An embodiment of the tape cassette of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing an essential part of an embodiment of the tape cassette of the present invention, FIG. 2 is a sectional view showing a molding process of an upper protrusion of the embodiment shown in FIG. 1, and FIG. 3 is a drawing showing the embodiment shown in FIG. FIG. 6 is a cross-sectional view showing a process of forming the lower protrusion.

As shown in FIG. 1, the tape cassette of the present embodiment detects the tape end of the magnetic tape 4 in a cassette body 1 which is composed of an upper half 2 and a lower half 3 in which a magnetic tape 4 is housed. It is provided with a pair of 45-degree reflecting surfaces 51 and 61 for returning the light L incident from the tape end sensor (not shown) to the sensor.

In the tape cassette of this embodiment, therefore, one of the pair of 45-degree reflecting surfaces 51 is formed on the upper projection 5 integrally provided on the upper half 2, and the other 61 is formed on the lower hard disk. It is formed on the lower projection 6 provided integrally with the frame 3.

The tape cassette of this embodiment will be further described. The upper protrusion 5 and the lower protrusion 6 each have a rectangular columnar shape with the same cross-sectional dimension, and the upper half 2 and the lower half 3 are formed in the cassette body 1 respectively. It is projected to face each other. At the tip of the upper protrusion 5, there is formed a reflecting surface 51 inclined at 45 degrees for reflecting the light L incident from the light emitting portion (not shown) of the tape end sensor toward the tip of the lower protrusion 6. The light reflected from the 45-degree reflecting surface 51 of the upper protrusion 5 is reflected at the tip of the lower protrusion 6 toward the light receiving portion (not shown) of the tape end sensor. A reflecting surface 61 inclined at 45 degrees is formed. The magnetic tape 4 is arranged at a position that blocks the optical path of the reflected light between the reflecting surface 61 and the light receiving portion.

The reflecting surfaces 51 and 61 in the present embodiment are formed with a surface roughness Ra <0.1 μm, but the reflected light becomes weak depending on the type of resin to be formed. In such a case, the reflecting surface may be formed by plating or attaching a film.

In the tape cassette of this embodiment configured as described above, when the upper half 2 and the lower half 3 are molded, the upper protrusion 5 is formed by the upper mold 7a and the lower mold 7b as shown in FIG. When integrally molding with the upper half 2, one side 51 of the 45-degree reflecting surface is formed at the tip thereof, and as shown in FIG. 3, the lower protrusion 6 is integrally molded with the lower half 3 by the upper mold 8a and the lower mold 8b. In doing so, the other side 61 of the 45-degree reflecting surface is formed at the tip.

As described above, in the tape cassette of this embodiment, one of the pair of the 45-degree reflecting surfaces 51 is formed at the tip of the upper protrusion 5 integrally provided on the upper half 2 and the other is formed. 61 is formed at the tip of the lower protrusion 6 integrally provided on the lower half 3, and neither upper protrusion 5 nor lower protrusion 6 is undercut. At the time of molding the half 2 and the lower half 3, the pair of 45-degree reflecting surfaces 51 and 61 can be easily integrally molded with the upper half 2 and the lower half 3 respectively without using a slide piece or the like. .

The present invention is not limited to the above embodiment, one of the pair of the 45-degree reflecting surfaces is formed on the upper projection integrally provided on the upper half, and the other is formed on the lower projection. It may be formed on the lower protrusion integrally provided on the harf.

[0016]

[Effect of the device]

 In the tape cassette of the present invention, the pair of 45-degree reflecting surfaces can be easily integrally formed with the upper half and the lower half of the cassette body.

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of an embodiment of a tape cassette of the present invention.

FIG. 2 is a cross-sectional view showing a molding process of the upper protrusion of the embodiment shown in FIG.

FIG. 3 is a cross-sectional view showing a process of forming a lower protrusion of the embodiment shown in FIG.

FIG. 4 is a view corresponding to FIG. 1 showing a prism portion of a conventional tape cassette.

FIG. 5 is a cross-sectional view showing a molding process of a prism portion of a conventional tape cassette.

[Explanation of symbols]

 1 cassette body 2 upper half 3 lower half 4 magnetic tape 5 upper protrusion 51 45 degree reflecting surface 6 lower protrusion 61 45 degree reflecting surface

Claims (1)

[Scope of utility model registration request] 1. A pair of 45-degree reflections for returning light incident from a tape end sensor for detecting a tape end of the magnetic tape to a cassette main body composed of an upper half and a lower half for housing the magnetic tape. In a tape cassette having a surface, one of a pair of the 45-degree reflecting surfaces is formed on an upper protrusion integrally formed on the upper half, and the other is formed on a lower protrusion integrally formed on the lower half. A tape cassette characterized by that.