JPS6030032B2 - tape cassette - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tape cassette, and in particular, the guide roller can be easily inserted into the guide roller support shaft formed integrally with the tape cassette case, and can be automatically inserted by an automatic insertion machine. This provides a flexible support shaft shape.

A tape cassette is provided with guide rollers to guide the tape stored inside.

As shown in FIG. 1, this guide roller generally has a guide roller support shaft 2 integrally formed with a cassette case made of synthetic resin, into which a guide loaf 3 is inserted so as to be freely rotatable. The guide roller support shaft 2 of the conventional tape cassette has a cylindrical shape as shown in FIG. The base is bent over the outer peripheral surface of the tip of the support shaft 2 with a slight flat surface 6 interposed therebetween. However, having the flat surface 6 around the guide roller 3 in this way means that if the guide roller 3 deviates even slightly from the support shaft 2 when the guide roller 3 is inserted, it will come into contact with the flat surface 6, making insertion difficult.
In particular, automatic insertion using an automatic insertion machine was impossible. In order to eliminate such problems when inserting the guide roller 3, the flat surface 6 described above can be released, but the molding of the cassette case 1 is performed using a fixed mold 7 as shown in FIG.
A protruding pin 1 is inserted into a hole 9 for forming a guide roller support shaft formed in the movable mold 8 and the movable mold 8, and a protruding pin 1 is inserted between the fixed mold 7 and the movable mold 8 for forming a cassette case. A synthetic resin material is injected into the space 11 and the space 12 formed by inserting the pen 10 that protrudes halfway from above into the hole 9 for forming the guide roller support shaft, and is then removed from the mold. The mold 8 is opened and the ejection pin 10 is used to extrude the product. In this case, the protrusion 4 and flat surface 6 at the tip of the guide roller support shaft 2 are connected to the small diameter recess 13 of the protruding pin 10.
However, in order to eliminate the flat surface 6, the recess 13 is enlarged and the slope 1 of the recess 13 is increased as shown in FIG.
3a must intersect with the outer peripheral surface of the tip of the protruding pin 10 at a sharp edge 13b.However, if such a sharp edge 13b is formed all around the circumference, the strength of the edge will be weakened. , it is damaged due to the pressure etc. during molding, resulting in a mold failure and making it impossible to mold a cassette case.

The present invention provides a shape of the guide roller support shaft that allows easy insertion of the guide roller, including the problem of the mold, and one embodiment thereof will be explained below using FIGS. 5 to 7. . First, the cylindrical guide roller support 14 has a triangular pyramid-shaped protrusion 15 formed at its tip, as shown in FIG.
The three ridge lines 16 extending radially from the apex of the protrusion 15 in a sloping manner reach directly the outer periphery of the tip of the support shaft 14, so that three flat parts 17 are formed at the base of the slope of the protrusion 15. It is formed.

In this way, a tapered protrusion 15 is formed at the tip of the guide roller support shaft 14, and only three radially inclined portions of the protrusion 15 from the top directly intersect with the outer peripheral surface of the guide roller support shaft 14. Therefore, even if the guide roller 18 is slightly misaligned when inserting the guide roller, as shown in FIG. 6, it is corrected by the ridge line 16 in the direction of the arrow as the guide roller is inserted, and is automatically moved to the correct insertion position. It is something that will be done. Figure 7 shows the guide roller support 14.
This figure shows an ejection pin 19 that molds a protrusion 15 at the tip of the protrusion pin 19, and the ejection pin 19 has a triangular pyramid-shaped recess 2 at its tip.
0 is formed, and the three square lines of the recess 20 are directly connected to the outer peripheral surface of the ejector pin 19.

Since flat portions 21 are formed at three locations on the tip surface of the ejecting pin 19, the outer peripheral surface of the ejecting pin 19 and the slope of the recess 20 sharply intersect only at three partial edge portions 22. Therefore, there is no damage caused by pressure during molding, and the problem of the mold being damaged is also eliminated.

8 to 11 show a guide roller support shaft 23 according to another embodiment of the present invention, in which a flat portion 25 is formed at the top of each of these protrusions 24, and FIG. 8 shows a triangular pyramid shape. The ridge of the protrusion 24 in FIG. 9 is formed into an arc shape, the protrusion 24 in FIG.
The base is formed of a conical protrusion having a smaller diameter than the outer diameter of the support shaft 23, a flat portion 25, and a plurality of connecting ribs 26 that radially connect the outer peripheral surface of the support shaft 23, and FIG.
4 is formed by ten-shaped ribs, and the same applies to these.

As described above, the present invention forms a projection with a tapered tip at the tip of the guide roller support shaft provided in the cassette case,
Only a plurality of radially located locations on the slope of the protrusion are made to be directly different from the outer peripheral surface of the guide roller support shaft. Accordingly, when the guide roller is inserted, even if the guide roller is slightly misaligned with the guide roller support shaft, The guide roller is inserted while being automatically corrected, so it can be inserted by an automatic inserter, and the mold for forming the guide roller support shaft is not damaged, which is very effective.

[Brief explanation of drawings]

Figure 1 is a perspective view of the inner surface of the tape cassette, Figure 2 is a perspective view of the main parts of a conventional guide roller support shaft, Figure 3 is a sectional view of the mold, and Figure 4 shows other protrusions in the mold. FIG. 5 is a perspective view of essential parts of a guide roller support shaft according to an embodiment of the present invention, FIG. 6 is a partially sectional side view showing the guide roller in its inserted state, and FIG. 7 is a diagram showing the shape of the pin. A perspective view of the ejecting pin of the molding die, and FIGS. 8 to 11 are perspective views showing guide roller support shafts of other embodiments, respectively. 1...Tape cassette, 14...Guide loaf support shaft, 1
5... Protrusion, 16... Ridge line, 18...
...Guide roller, 23...Guide roller support shaft, 24...Protrusion. Fig. 10 Fig. 11 Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 8 Fig. 9

Claims (1)

[Claims] 1. A guide roller support shaft for supporting a guide roller of the tape is provided in a cassette case for storing a tape, and a protrusion with a tapered tip is formed at the tip of the guide roller support shaft, and a protrusion is formed radially on the inclined part of the protrusion. A tape cassette characterized in that only a plurality of locations where the tape cassette is connected directly to the outer circumferential surface of the guide roller support shaft.