JPH08203242A - Tape cassette - Google Patents

Abstract

PURPOSE: To obtain a tape cassette which prevents drop in sound quality due to the damage of a magnetic tape by making a tape cassette have a constitution wherein a recessed part which houses a burr protruding by a welding operation is formed in the butting part of a positioning pin. CONSTITUTION: Positioning pins 24, 25 by which a gap between an upper shell 2 and a lower shell 3 forming a tape housing chamber in held to be constant are installed at one pair of shells 2, 3 of the tape cassette. In the positioning pins 24, 24, ringed grooves 26, 27 which are continued in the circumferential direction are formed in butting parts as their tip parts. Thereby, even when a magnetic tape T comes into contact with side faces of the positioning pins 24, 25, a welding burr 28 does not come into contact with a magnetic face of the magnetic tape T. As the result, it is possible to prevent the magnetic tape T from being damaged due to the burr 28.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape cassette using a magnetic tape as an information recording medium, and more particularly, a cassette in which a pair of upper and lower shells are superposed and welded at a contact surface to integrate the pair of shells. The present invention relates to a tape cassette that forms a housing.

[0002]

2. Description of the Related Art Conventionally, as a tape cassette of this type, there are those shown in FIGS. 11 to 13, for example. FIG. 11 is a plan view showing a state in which the upper shell 2 forming one of the cassette housings 1 is laterally cross-sectioned. A pair of tape reels 5, 6 around which a magnetic tape T is wound from both sides are rotatably accommodated in a tape accommodating chamber 4 provided inside a pair of upper and lower shells 2, 3. The magnetic tape T wound on one of the tape reels 5 passes through the guide roller 7 and the opening 9 on one side through the tape accommodating chamber 4.
It is exposed to the outside, passes through the mouth part 11, and the other opening 10
From the inside again into the tape storage chamber 4 and the guide roller 8
And is wound on the other tape reel 6.

In the pair of shells 2 and 3 of the tape cassette having such a structure, positioning pins 12 and 13 for keeping the inner size of the tape accommodating chamber 4, that is, the gap between the tape accommodating chambers 4 constant, are provided. It is provided. The pair of positioning pins 12 and 13 are formed so as to overlap each other in the vertical direction when the shells 2 and 3 are overlapped with each other, and ultrasonic welding is performed in the superposed state to melt the abutting portions of each other. By doing so, the pair of shells 2 and 3 are integrated.

[0004]

However, in the conventional tape cassette as described above, when the upper and lower shells 2 and 3 are welded, both shells 2 and 2 are formed in order to increase the welding strength.
When 3 is strongly pressed, as shown in FIG. 12, the welded portion protrudes outward from the outer peripheral surfaces of the positioning pins 12 and 13, and burrs 14 are generated. In this way, the positioning pins 12, 13
When the burr 14 is generated at the welded portion between the tape reels 5 and 6, the winding force of the tape reels 5 and 6 is loosened and the magnetic tape T is slackened. There was a problem that it would hurt.

In this case, there is no problem while the leader tape connecting the tape reels 5 and 6 and the magnetic tape T is in contact with the burr 14, but the leader tape passes and the magnetic tape T comes into contact with the burr 14. In this case, there is a problem that the magnetic tape T is scratched and the sound quality is deteriorated. In particular, in recent years, since the length of the leader tape tends to be set short, the above problems are likely to occur.

Further, with respect to the above-mentioned problems, the same can be said with respect to the side surface plate as the overlapping portion where the pair of shells 2 and 3 are superposed. FIG. 13 is an explanatory diagram showing a state in which the side plates 2a and 3a of the pair of shells 2 and 3 are welded to each other. In the center of the side plate 2a of the upper shell 2,
Welding ribs 15 each having a triangular cross-sectional shape extending in the surface direction of the side surface plate 2a are provided at a plurality of positions with an appropriate length. By welding the side plates 2a and 3a having such welding ribs 15 by ultrasonic welding, the pair of shells 2 and 3 are welded and integrated.

In this case, the welding condition is usually set within the range where the protrusion does not occur, but there are cases where sufficient welding strength cannot be secured, and if the welding becomes stronger than the normal welding condition, it is shown in FIG. As described above, the burr 14 is generated at the welded portion due to the protrusion. Thus a pair of shells 2,
When the burr 14 is generated between the side plates 2a and 3a of the No. 3, not only is it uncomfortable to feel on the outside of the cassette housing 1, but also it looks bad, and the magnetic tape is on the inside of the cassette housing 1. There is a risk that the magnetic surface may be damaged by contact when T is loosened, which is not functionally preferable.

The present invention has been made in view of such conventional problems. Even when a burr due to welding is generated between a pair of shells, the burr does not come into contact with the magnetic tape, and the magnetic tape is made magnetic. An object of the present invention is to provide a tape cassette that does not damage the magnetic surface of the tape.

[0009]

The present invention solves the above-mentioned problems and the like, and in order to achieve the above-mentioned object, in the tape cassette of the present invention, the magnetic tapes of a pair of positioning pins can contact each other. It is characterized in that at least one of the positioning pins on a certain surface is provided with a recess for accommodating the burr protruding by welding and preventing the magnetic tape from coming into contact with the burr.

Further, in the tape cassette of the present invention, the magnetic tape is formed by accommodating burrs protruding by welding in at least one of the superposed portions of the superposed portions of the shells which may come into contact with the magnetic tape. It is characterized in that a recess is provided to prevent contact with the burr.

[0011]

The present invention has the above-mentioned configuration,
Even when the magnetic tape comes loose due to the looseness of the winding force of the tape reel and the magnetic tape comes into contact with the positioning pin, the burrs formed by welding are contained in the recesses provided in the positioning pin, and the magnetic tape is positioned at the positioning pin. Since it does not come into contact with the burr, there is no fear that the burr will damage the magnetic tape.

Similarly, when the magnetic tape is loosened by loosening of the winding force of the tape reel and the magnetic tape comes into contact with the overlapping portions of the pair of shells, the burr formed by welding is provided in the overlapping portions. Stored in the recess
Since the magnetic tape does not come into contact with the burr of the overlapping portion, there is no possibility that the magnetic tape will be damaged by the burr.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 10 show an embodiment of the present invention, FIG. 1 is an exploded perspective view of a tape cassette showing an embodiment of the present invention, and FIGS. 2 to 7 are views in which the present invention is applied to a positioning pin. FIGS. 8 to 10 are explanatory views showing examples, respectively, showing the embodiments in which the present invention is applied to the side plates. still,
1 to 10, the same parts as those of FIGS. 11 to 13 showing the conventional example are designated by the same reference numerals and described.

The cassette housing 1 shown in FIG. 1 is composed of a pair of upper shell 2 and lower shell 3 which are vertically stacked.
Each of the shells 2 and 3 is formed of a synthetic resin having appropriate rigidity (for example, ABS resin). The upper shell 2 has two insertion holes 16 and 1 into which the reel drive shaft is inserted.
A quadrilateral top plate 2a having 6 and side plates 2b continuous with the four sides of the top plate 2a and provided on both ends of the front face and on the rear face and left and right sides respectively, and between the front face plates 2b, 2b. The upper wall 2c is formed of a mouse wall 2c that forms the upper part of the portion 11, and two reference holes 17, 17 for positioning, and capstan holes 18, which are arranged outside each reference hole 17, are provided on the front part of the top plate 2a. And 18 are provided.

The lower shell 3 also has a rectangular lower surface plate 3a having two insertion holes into which reel drive shafts are inserted.
And a side plate 3b which is continuous with the four sides of the bottom plate 3a and is provided on both ends of the front face and on the rear face and left and right sides, respectively, and a mouse which is provided between the front side plates 3b and 3b and forms the lower part of the mouse portion 11. The lower surface plate 3a is provided with two reference holes for positioning and a capstan hole arranged outside each of the reference holes. By stacking the pair of shells 2 and 3 having such a configuration vertically, the cassette housing 1 having the tape storage chamber 4 therein is configured.

In the tape housing chamber 4 of the cassette housing 1, a pair of tape reels 5 and 6 each having a magnetic tape T wound from both sides are rotatably housed. An upper sheet 20 is interposed between the tape reels 5 and 6 and the upper shell 2, and a lower sheet 21 is interposed between the tape reels 5 and 6 and the lower shell 3. Reel 5,
The reel holes 5a and 6a of 6 are assembled so as to coincide with the insertion holes of the upper and lower sheets 20 and 21 and the insertion holes of the upper and lower shells 2 and 3. Most of the magnetic tape T is wound around the supply-side reel 5 which is one of the tape reels, and the magnetic tape T ejected from the supply-side reel 5 passes through the guide pin 22 and the guide roller 7 and one opening 9 is formed. Is exposed outside the tape storage chamber 4. Then, the magnetic tape T that has come out of the tape accommodating chamber 4 passes through the mouth portion 11 and enters the tape accommodating chamber 4 again through the other opening 10, and passes through the guide roller 8 and the guide pin 23 to the other tape reel. Is wound on the take-up reel 6.

In the pair of shells 2 and 3 of the tape cassette having such a structure, the inner size of the tape accommodating chamber 4, that is, the gap between the upper and lower shells 2 and 3 forming the tape accommodating chamber 4 is kept constant. Positioning pins 24 and 25 are provided for this purpose. The pair of positioning pins 24, 25 are formed at positions that vertically overlap each other when the shells 2, 3 are superposed, and ultrasonic welding is performed with the tips of the positioning pins 24, 25 abutting each other. By
Both abutment portions can be melted to connect the positioning pins 24 and 25.

It is preferable that these positioning pins 24 and 25 have, for example, a shape as shown in FIG. Figure 2
The positioning pins 24 and 25 shown in FIG. 2 are cylindrical bodies, respectively, and annular grooves 26 and 27 that are continuous in the circumferential direction are provided at the abutting portions that are the tips of the annular pins 26 and 27. The first specific example of the recess is formed. Specific sizes of the annular grooves 26 and 27 can be set as follows. For example, in the case of an ordinary tape cassette used for recording music, conversation, etc., the thickness D of the positioning pins 24, 25 is 1.6 mm, but the size of the annular grooves 26, 27 in this case is large. Saha
The width B may be about 0.5 mm and the depth C may be about 0.2 mm. Therefore, the diameter d of the abutting portion left at the tips of the positioning pins 24 and 25 is 1.2 mm.

When the annular grooves 26 and 27 are set to have such a size, when the pair of positioning pins 24 and 25 are butted against each other and ultrasonic welding is performed, the height of the burr 28 generated at the abutting portion is thereby caused. Varies depending on the material used and the strength of the welding strength that is set, but generally 0.1 to
It will be about 0.2 mm. Therefore, as shown in FIG. 2, even when the magnetic tape T comes into contact with the side surfaces of the positioning pins 24 and 25, the welding burr 28 does not come into contact with the magnetic surface of the magnetic tape T. It is possible to prevent the tape T from being scratched.

In FIG. 3, the shape of the recess is an annular groove 30 having a triangular cross section. Also, FIG.
Is the annular groove 3 whose cross-sectional shape is an arc shape.
1,31. In this way, the annular groove 26,
27, 30, 30, 31, 31 may be provided on both abutting portions of the pair of positioning pins 24, 25, but as shown in FIG. 5, they may be provided on only one positioning pin 24 or 25. It is possible to obtain the same effect as the above embodiment.

That is, in FIG. 5, an annular groove 26 is provided only in the upper positioning pin 24 in the embodiment shown in FIG. 2, and a concave portion for accommodating the burr 28 is formed only in the annular groove 26. . As the shape of such an annular groove,
In addition to the shape shown in FIG. 5, it is needless to say that the shape shown in FIGS. 3 and 4 can be applied, and recesses having other shapes can be applied.

6 and 7, the positioning pin 3 is shown.
Another embodiment of the recesses provided in Nos. 2 and 33 will be shown. The recessed portion shown in FIG. 6 has partial grooves 34, 35 only in the abutting portions of the surfaces of the positioning pins 32, 33 with which the magnetic tape T may come into contact.
Is provided. The partial grooves 34 and 35 extend in the circumferential direction to both side surfaces with the front side of the cassette housing 1 as the center. In the embodiment shown in FIG. 6, if the burr 28 is formed over the entire range in the circumferential direction, the positioning pin 3
A burr 28 is formed on the surface of the abutting portions 2 and 33 where the magnetic tape T does not come in contact (the rear surface on the left side in the figure).
However, since the magnetic tape T does not contact the burr 28 of such a protruding portion, there is no problem that the magnetic tape T is scratched.

Further, in the embodiment shown in FIG. 7, the partial grooves 36, 3 having substantially the same shape as the partial grooves 34, 35 shown in FIG.
Of the pair of locating pins 32 and 33 having 7, the welding rib 3 having a conical shape at the tip of the upper locating pin 32.
8 is provided. The welding rib 38 is melted by ultrasonic welding and spreads over the entire surface of the abutting portion like an adhesive, and the upper and lower positioning pins 32, 33 are interposed via the welding portion.
Are combined.

In this case, in the embodiment shown in FIG. 7, the center line of the welding rib 38 is set to be displaced from the center line of the positioning pin 32 toward the partial groove 34 with a displacement e. With such a configuration, the length of the welding rib 38 that melts and flows to the back side can be increased, and the burr 28 can be prevented from reaching the back side, and thus the protrusion to the back side can be prevented. In particular, this embodiment is effective when the positioning pins 32 and 33 have large diameters.

The embodiment shown in FIGS. 8 to 10 is one in which the present invention is applied to the side plate. Usually, of the pair of upper and lower shells 2 and 3, the end faces of the side plate 2b (or 3b) and the mouse wall 2c (or 3c) provided on the four sides of one shell 2 (or 3) are appropriately arranged in the plane direction. A triangular chevron-shaped welding rib 40 extending in length is formed.
0 melts by ultrasonic welding like the rib 38, and the upper and lower shells 2 and 3 are welded. in this case,
Regarding the specific size of the welding rib 40, for example, in the case of an ordinary tape cassette used for recording music, conversation, etc., the width G is 0.5 mm to 0.3 mm and the height H is H.
Is about 0.1 mm to 0.2 mm.

In such a side plate 2b, continuous grooves 41, 42 and 43, 4 showing a concrete example of recesses on both inner and outer surfaces.
8 shows an example in which the continuous groove 4 is provided only on the inner surface.
FIG. 9 shows an example in which 1, 43 are provided. In FIGS. 8 and 9, the continuous grooves 41, 42, 43, and 44 are all continuous in the edge direction and make one round around the cassette housing 1.

In the embodiment shown in FIG. 8, however, when the cassette housing 1 is assembled, ultrasonic welding is performed on the pair of upper and lower shells 2 and 3 to weld the side plates 2b and 3b, and the melted welding ribs are released. A part of 40 is projected on both the inner and outer surfaces, and they are solidified to form burrs 28, 28. However, these burrs 28 are housed in the continuous grooves 41, 43 on the inner surface and the continuous grooves 42, 44 on the outer surface, respectively, and the tips of the burrs 28 are positioned farther than the inner and outer surfaces of the side plates 2b, 3b. Does not project outside. Therefore, even when the magnetic tape T loosens and comes into contact with the inner surfaces of the side plates 2b and 3b, the burr 28 protruding inward does not damage the magnetic tape T.

Further, in the embodiment shown in FIG. 9, when the cassette housing 1 is assembled, the pair of upper and lower shells 2 and 3 are ultrasonically welded to each other to weld the side plates 2b and 3b to each other so that the melted welded A part of the rib 40 sticks out on both the inside and outside of the burr 2
8 and 28 are generated, the burr 28 protruding to the outer surface of the side surface plates 2b and 3b does not affect the magnetic tape T in the tape accommodating chamber 4, so that there is no problem.
The burrs 28 projecting from the inner surfaces of b and 3b are continuous grooves 41 and 43.
Since it is housed inside, the magnetic tape T is attached to this burr 28.
Does not come into contact with. Therefore, also in this case, the magnetic tape T is loosened and the side plates 2b and 3b are released as in the above embodiment.
Even when it contacts the inner surface of the magnetic tape T, the burr 28 protruding inward does not damage the magnetic tape T.

Further, in the embodiment shown in FIG. 10, the burr 28 which is exposed on the outer surfaces of the side plates 2b and 3b in the embodiment shown in FIG.
However, the side plates 2b and 3b are designed so as not to project outward from the outer surfaces thereof. In this case, as shown in FIG.
This can be easily realized by disposing the welding rib 40 so as to be offset toward the continuous grooves 41, 43 with the displacement amount e. That is, in this embodiment, as in the embodiment shown in FIG. 7, the distance to the back side becomes longer, so that the ends of the melted welding ribs 40 do not reach the outer surfaces of the side plates 2b, 3b. The position of the rib 40 is set.

The present invention is not limited to the above embodiments, but can be variously modified without departing from the spirit thereof.

[0031]

As described above, according to the present invention,
Since the concave portion for accommodating the burr protruding due to welding is provided at the abutting portion of at least one of the positioning pins, there is no risk of scratching the magnetic tape even when the magnetic tape comes into contact with the positioning pin. It is possible to prevent deterioration of sound quality due to attachment. Furthermore, the length of the leader tape can be shortened, and the tape cassette (for example, audio compact cassette) having a short leader tape can be commercialized.

Further, according to the present invention, since the recessed portion for accommodating the burr protruding due to the welding is provided in the overlapping portion of at least one shell, the magnetic tape can be used even when the magnetic tape comes into contact with the overlapping portion. It is possible to prevent scratches on the magnetic surface of the magnetic tape due to contact with burrs. Further, even if the welding rib is made larger, the protruding burr is accommodated in the concave portion, so that the effect that the welding rib can be made larger and the welding strength can be increased is obtained.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a tape cassette showing an embodiment of the present invention.

FIG. 2 is an explanatory view showing a first embodiment in which the present invention is applied to a positioning pin.

FIG. 3 is an explanatory view showing a second embodiment in which the present invention is applied to a positioning pin.

FIG. 4 is an explanatory view showing a third embodiment in which the present invention is applied to a positioning pin.

FIG. 5 is an explanatory view showing a fourth embodiment in which the present invention is applied to a positioning pin.

FIG. 6 is an explanatory view showing a fifth embodiment in which the present invention is applied to a positioning pin.

FIG. 7 is an explanatory view showing a sixth embodiment in which the present invention is applied to a positioning pin.

FIG. 8 is an explanatory diagram showing a first embodiment in which the present invention is applied to a side plate.

FIG. 9 is an explanatory view showing a second embodiment in which the present invention is applied to a side plate.

FIG. 10 is an explanatory diagram showing a third embodiment in which the present invention is applied to a side plate.

FIG. 11 is a plan view showing a cross section of an upper shell showing a conventional tape cassette.

FIG. 12 is an explanatory diagram showing a state of a conventional positioning pin.

FIG. 13 is an explanatory diagram showing a state of a conventional side plate.

[Explanation of symbols]

 1 cassette housing 2 upper shell 3 lower shell 2b, 3b side plate (overlapping part) 4 tape accommodating chamber 5,6 tape reel 24, 25 positioning pin 26, 27, 30, 31 annular groove (recess) 28 burr 34, 35, 36, 37 Partial grooves (recesses) 38, 40 Welding ribs 41, 42, 43, 44 Continuous grooves (recesses)

Claims (10)

[Claims] 1. A pair of tape reels for winding and feeding out a magnetic tape wound from both sides are rotatably accommodated in a tape accommodating chamber formed in a pair of upper and lower shells that are superposed on each other, respectively. Tape cassette in which a pair of shells are integrated by abutting a pair of positioning pins projecting from the shell into the tape housing chamber to hold a constant gap in the tape housing chamber and at least welding between the positioning pins to each other In the above, at least one positioning pin of the pair of positioning pins on which the magnetic tape may come into contact is provided with a recess for accommodating the burr protruding by the welding and preventing the magnetic tape from contacting the burr. A tape cassette characterized by being provided. 2. The tape cassette according to claim 1, wherein the recess for accommodating the burr is an annular groove provided in the positioning pin and continuous in the circumferential direction. 3. The tape cassette according to claim 1, wherein the recess for accommodating the burr is a partial groove provided on a surface of the positioning pin with which the magnetic tape may come into contact. . 4. The tape cassette according to claim 1, 2, or 3, wherein at least one positioning pin of the pair of positioning pins is provided with a welding rib that melts and welds the contact surfaces of the respective positioning pins. Tape cassette characterized by. 5. The tape cassette according to claim 1, wherein the recess for accommodating the burr is a partial groove provided on a surface of the positioning pin that may come into contact with the magnetic tape,
A tape cassette, characterized in that a welding rib, which melts and welds between the contact surfaces, is provided in a biased manner on the side where the partial groove is located. 6. A pair of tape reels for winding and delivering a magnetic tape wound from both sides are rotatably accommodated in a tape accommodating chamber formed in a pair of upper and lower shells which are overlapped with each other. In a tape cassette in which a pair of shells are integrated by welding at least a part of the superposed portions between the shells to each other, at least one of the surfaces of the superposed portions of the pair of shells that may come into contact with the magnetic tape A tape cassette, characterized in that the overlapping portion is provided with a recess for accommodating the burr protruding by the welding and preventing the magnetic tape from coming into contact with the burr. 7. The tape cassette according to claim 6, wherein the recess for accommodating the burr is a continuous groove provided on the inner surface of the overlapping portion of one of the shells and continuous in the surface direction. cassette. 8. The tape cassette according to claim 6, wherein the recess for accommodating the burr is a continuous groove provided on both the inner surface and the outer surface of the overlapping portion of the one shell and continuous in the respective surface directions. Tape cassette characterized by. 9. The tape cassette according to claim 6, 7 or 8, wherein at least one shell of the pair of shells has a welding rib at a superposed portion for welding between the superposed portions by melting. A tape cassette characterized by being provided. 10. The tape cassette according to claim 6, wherein the recess for accommodating the burr is a continuous groove provided on the inner surface of the overlapped portion of one of the shells, and the gap between the overlapped portions is melted by melting. A tape cassette, wherein a welding rib to be welded is provided so as to be biased to the side where the continuous groove is provided.