JPS6318272B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tape cassette that is most suitable for application to recording and reproducing devices such as video tape recorders and other various information processing devices.

As is well known, tape cassettes for video tape recorders have conventionally been provided with a pair of fulcrum pins integrally inside the pair of left and right side plates of the front cover, which have a substantially U-shaped planar shape. is rotatably attached to the cassette housing by the above pair of fulcrum pins,
The front cover of the cassette case is configured to be opened and closed by rotation of the front cover, and a torsion coil spring is attached to the inside of at least one side plate of the front cover,
The torsion coil spring biases the front lid to close.

By the way, in conventional tape cassettes of this type, the torsion coil spring is attached to the outer periphery of the fulcrum pin within the gap between the side plate of the front cover and the side wall of the cassette housing. After installing the torsion coil spring, it is not possible to install the torsion coil spring. Conventionally, therefore, when assembling this type of tape cassette, the front cover is attached to the cassette casing with the torsion coil spring inserted in advance around the outer periphery of the fulcrum pin. Because it was only inserted, when assembling the front cover, the torsion coil spring could rotate freely around the fulcrum pin and its direction could change, or it could easily fall off from the tip of the fulcrum pin. There was a significant inconvenience when assembling the front cover.

The present invention was invented in view of the above-mentioned circumstances, and provides a tape cassette which can be attached to a cassette housing together with a front cover with a torsion coil spring temporarily fixed to the front cover. This is what I am trying to do.

An embodiment in which the present invention is applied to a tape cassette for a video tape recorder will be described below with reference to the drawings.

As shown in FIGS. 1 to 3, a cassette housing 1 constituting a tape cassette is composed of a rectangular upper half 2 and a lower half 3 made of synthetic resin. They are fitted into each other from above and below, and are screwed together with setscrews 4 to 7 to form an integrated casing. A pair of tape reels 8 and 9 are rotatably housed within this cassette housing 1, and are used to store magnetic tape (hereinafter simply referred to as "tape").
) 10 is wound around both tape reels 8 and 9. Note that the lower ends of the reel hubs 8a, 9a of both tape reels 8, 9 are fitted into a pair of reel fitting holes 11, 12 provided in the bottom wall 3a of the lower half 3, as shown in FIG. Horizontal positioning is done. A pair of presser springs 13 are housed in each of the reel hubs 8a, 9a, and a pair of caps 14 are placed over the upper ends of the pair of presser springs 13. Then, when the tape cassette is installed in the cassette installation position inside the video tape recorder body, a pair of reel hubs 8
A pair of reel drive shafts (not shown) are inserted into a and 9a, and at this time, the pivot portions 15 of the pair of caps 14 abut against the upper wall 2a of the upper half 2, while both tape reels 8 and 9 are held against the presser spring 13. Therefore, the tape reels 8a, 9 are energized toward the reel drive shaft side, and the lower end surfaces of the respective reel hubs 8a, 9a come into contact with the positioning surfaces of the pair of reel drive shafts, so that the tape reels 8, 9 are positioned in the vertical direction. It is configured.

As shown in FIG. 2, a front opening 18 is provided on the front surface of the cassette housing 1, extending substantially over the entire width of the cassette. Also, on the bottom wall 3a of the lower half 3, there is a second
As shown in FIG. 3, FIG. 5, a bottom opening 19 is provided which is continuous with the front opening 18. Furthermore, as shown in FIG. 3, the upper wall 2a of the upper half 2 is provided with an upper opening 20 extending over its entire width and continuous with the front opening 18. The tape cassette is normally opened at its front opening 18 as shown in FIG.
is connected to the front lid 37, and the top opening 20 is connected to the top lid 3.
8, and as shown in FIGS. 5 and 12, the front opening 18 and the bottom opening 19 are separated by a rear lid 39.

Along the edge of the bottom opening 19, a partition wall 21 stands perpendicularly from the edge as shown in FIG.
is integrally molded with the lower half. Further, another partition wall 22 symmetrical to this partition wall 21 is integrally molded on the upper surface wall 2a of the upper half 2. When the upper and lower halves 2 and 3 are fitted together, the upper end surface of the partition wall 21 and the lower end surface of the partition wall 22 are in close contact with each other, so that the inside of the cassette housing 1 is connected to the bottom opening 19 side and both tape reels. Partition walls 21 and 22 between the 8 and 9 sides
It is configured to be partitioned by. When fitting the upper and lower halves 2 and 3 together, the tape 10 should be pulled out slightly as shown in FIG. 3 in order not to damage the tape 10. Furthermore, as shown in FIG. 8, a pair of positioning holes 17 are formed at both left and right ends of the partition wall 21 and are opened at the bottom surface of the lower half 3, so that when the tape cassette is installed in the video tape recorder body, the positioning hole 17 is positioned at the cassette installation position. A pair of positioning pins 1 provided
6 is inserted into the pair of positioning holes 17 to position the tape cassette.

A pair of guide surfaces 23 are formed at both left and right ends of the partition wall 21, as shown in FIG.
Another pair of guide surfaces 24 having the same shape as this guide surface 23 are formed at both left and right ends of the guide surface 2 . The guide surfaces 23 and 24 each have a dogleg shape, that is, they consist of vertical surface portions 25 and 26 that are perpendicular to each other and slope portions 27 and 28 that are slightly inclined, and both the upper and lower halves 2 and 3
The structure is such that the guide surfaces 23 and 24 can be formed simultaneously without producing an undercut when injection molding is performed using a mold. When the upper half 2 is fitted to the lower half 3 from the direction of arrow a in FIG.
As shown in FIG. 0, a pair of guide grooves 31 are formed into which a pair of guided pins 81 of a rear lid 39, which will be described later, are inserted. Therefore, when forming the guide groove 31 independently in the lower half 3, it was impossible to mold the upper half 2 with a mold because undercut would occur, but as described above, the guide surface 2
Since the guide groove 31 is formed by making the guide grooves 3 and 24 face each other, the guide surfaces 23 and 24 of the guide groove 31 can be molded at the same time when both the upper and lower halves 2 and 3 are injection molded using a mold. Good manufacturability.

A pair of cylindrical tape guide surfaces 32 are also formed at both left and right ends of the partition wall 22 in front of the guide surface 24, as shown in FIG. The lower end portions of the pair of tape guide surfaces 32 extend to the bottom wall 3a of the lower half 3 so that no seams are formed on the tape guide surfaces 32, and the tips of the setscrews 4 and 5 are inserted inside the lower end portions of the pair of tape guide surfaces 32. It is designed to be screwed in. Then, the tape 10 is
As shown in FIGS. 4 and 5, the tape is guided by a pair of tape guide surfaces 32 and stretched along the front opening 18.

A pair of bracket portions 36 are provided at both left and right ends of the front side of the upper half 2, as shown in FIGS. 3 and 8. As shown in FIGS. The pair of bracket portions 36 are provided with a pair of pin holes 42 into which the pair of fulcrum pins 41 of the front lid 37 are inserted. A pair of inclined surfaces 44 are formed on the outer surfaces of the pair of bracket parts 36 from the upper end surface 43 of the bracket part 36 to the edges of the pair of pin holes 42, and the pair of fulcrum pins 41 of the front lid 37 are connected to the eighth It is configured such that it can be inserted into a pair of inclined surfaces 44 from the direction of arrow b in the figure, and a pair of fulcrum pins 41 can be inserted into a pair of pin holes 42 in a click manner. Therefore, the front cover 37 can be easily attached.

As shown in FIG. 8, on the bottom wall 3a at both left and right ends of the front side of the lower half 3, there are provided elastic locking pawls 46 formed of synthetic resin and having a substantially U-shape. A mounting hole 48 is provided in the base end 47 of the lock claw body 46.
A fixing pin 49 provided on the bottom wall 3a is inserted and then heat welded. Note that the base end portion 47
The rotation of is regulated by a pair of retaining pins 50. The tip of the lock claw body 46 has an inclined portion 51.
This claw portion 52 projects outward from a pair of claw holes 53 provided in the left and right side walls 3b of the lower half 3.

Above, the structure of the front side of both the upper and lower halves 2 and 3 has been described, but next, the front cover 37 and the upper cover 3
8 and the rear lid 39 will be explained in detail. First, the front lid 37 has a substantially U-shaped planar shape as shown in FIGS. 6 and 7, and has a pair of left and right side plates 37a.
A pair of fulcrum pins 41 are integrally formed on the inner surface of the holder. The pair of fulcrum pins 41 are pivotally supported by the pair of pin holes 42 of the pair of bracket parts 36, so that the front cover 38 can freely rotate. As shown in FIG. 8, a pair of spring locking protrusions 56 and 57 are integrally formed on the inner surface of the side plate portion 37a in close proximity to both left and right sides of the fulcrum pin 41. As shown in FIG. 8, a pair of torsion coil springs 58 are inserted and attached to the outer periphery of the pair of fulcrum pins 41 by means of their central coil portions 58c. One end 58a and the other end 58b of the pair of torsion coil springs 58 are locked to the pair of spring locking protrusions 57 and 56 in a slightly torsionally biased state. In particular, the spring locking convex portion 5
7 is for temporarily fixing one end 58a of the torsion coil spring 58, and when the front cover 37 is attached to the pair of bracket parts 36 from the direction of arrow b in FIG. One end portion 58a is separated from the temporary fixing convex portion 57 and is pressed against and locked by a pair of regular spring locking portions 59 which are the left and right ends of the front edge of the upper half 2. There is. Therefore, when attaching the front cover 37 to the cassette case 1, the front cover 37 is attached in order to prevent the torsion coil spring 58 from accidentally falling off the fulcrum pin 41.
The torsion coil spring 58 thus temporarily fixed can be easily attached to the cassette case 1 together with the front cover 37. When the cover 37 is attached to the cassette case 1, one end 58a of the torsion coil spring 58 pressed against the spring locking part 59 of the cassette case 1 is strongly twisted counterclockwise in FIG. , the front cover 37 is attached to the torsion coil spring 58.
A spring force is accumulated that urges the fulcrum pin 41 to rotate counterclockwise in FIG. 9 about the fulcrum pin 41.

A pair of lock holes 60 are provided at the lower portions of the pair of side plate portions 37a of the front lid 37. Also, the front lid 37
A pair of slits 61 are provided at both left and right ends of the lower edge. The lock hole 60 is arranged at a position facing the claw hole 53 when the front lid 37 is closed, and the slit 61 communicates between the side wall 3b of the lower half 3 and the side plate portion 37a of the front lid 37. has been done. Therefore, the claw portions 52 of the pair of lock claw bodies 46 protruding from the pair of claw holes 53 are engaged with the pair of lock holes 60 when the front cover 37 is closed, but the tape cassette is not inserted into the main body of the video tape recorder. When installed inside the video tape recorder, a pair of lock release pieces 62 provided inside the video tape recorder body are inserted into the pair of slits 6 as shown in FIGS. 1 and 2.
1 is inserted in the direction of arrow j, and the pair of claws 52 and the lock hole 60 are disengaged from each other.

A pair of pin holes 63 are provided at the upper front side of the pair of side plate portions 37a of the front lid 37, as shown in FIGS. 6 and 7. On the other hand, a pair of fulcrum pins 64 and 65 are provided at both left and right ends of the upper lid 38, and the pair of fulcrum pins 64 and 65 are inserted into the pair of pin holes 63 so that the upper lid 38
It is said to be freely rotatable around 4. Note that one fulcrum pin 65 is longer than the other fulcrum pin 64, and a substantially C-shaped spacer 66 is click-fitted to the fulcrum pin 65 as shown in FIG. 64 and 65 are both pin holes 63
It is made to stay in place. That is, as shown in FIG. 7, the fulcrum pin 65 is provided to protrude from the notch step 67, and when attaching the top cover 38 to the front cover 37, the top cover 38 is first set up as shown by the dashed line in FIG. In this state, the fulcrum pin 65 is inserted into one pin hole 63, and then the upper cover 38 is slightly shifted laterally and the fulcrum pin 64 is inserted into the other pin hole 63. Then, the upper cover 38 is rotated in the direction of arrow c in FIG. 7 to make it horizontal, and the spacer 66 is clicked into the fulcrum pin 65 from the direction of arrow e in FIG. Since the spacer 66 is used in this way, the upper lid 38
The installation work is easy and the installation is reliable. The front edge of the upper lid 38 is formed into an arcuate surface 68 as shown in FIG. 7, so that there is no gap between the front edge of the upper lid 38 and the upper edge of the front lid 37. The rear edge of the upper lid 38 is shown in FIGS. 6 and 7.
As shown in FIGS. 9 and 10, the inclined surface 69
On the other hand, the front edge of the upper wall 2a of the upper half 2, which is in contact with the rear edge of the upper cover 38, is inclined at the same angle of inclination as the inclined surface 69, as shown in FIGS. 8, 9, and 10. It is assumed that the surface is 70. Therefore, the upper lid 38
When the top cover 38 is closed as shown in FIG.
8 can be slid rearward and upward as shown in FIG.

As shown in FIG. 6, a pair of spring locking portions 71 are provided at both left and right ends of the lower surface of the upper lid 38. As shown in FIG. A pair of spring locking portions 72 are also provided at both left and right ends of the inner surface of the front lid 37. A pair of tension springs 73 are installed between the pair of spring locking parts 71 and 72, and the upper lid 38 is urged to rotate in the direction of arrow d in FIG. 6 by the pair of tension springs 73. There is. A pair of bracket parts 74 are also provided at both left and right ends of the lower surface of the upper lid 38, which are located slightly closer to the center than the pair of spring locking parts 71 and adjacent to the rear edge of the upper lid 38. A pair of fulcrum pins 76 and 77 provided at both left and right ends of the rear lid 39 are pivotally supported in a pair of pin holes 75 provided in the pair of bracket portions 74. It is said to be freely rotatable around 77. Note that one of the fulcrum pins 76 is provided to protrude from the notch step 78 and is configured to be longer than the other fulcrum pin 77. When attaching the rear lid 39 to the upper lid 38, first insert the fulcrum pin 76 into one pin hole 75, then shift the rear lid 39 a little laterally and insert the fulcrum pin 77 into the other pin hole 75. Then, a substantially C-shaped spacer 79 is click-fitted onto the fulcrum pin 76 from the direction of arrow f in FIG. By doing so, the work of attaching the rear cover 39 becomes easier and the attachment is ensured. Further, one side surface of the pair of bracket portions 74 forms a pair of sloped surface portions 74a that are continuous with the sloped surface 69 formed at the rear edge of the upper lid 38, and when the upper lid 38 moves rearward and upward, this pair of sloped surface portions 74a are continuous. The inclined surface portion 74a of the upper half 2 is configured to come into sliding contact with the inclined surface 70 of the upper half 2.

As shown in FIG. 6, a pair of bracket portions 80 are protrudingly provided near the lower end of the rear lid 39 at both left and right ends of the outer surface (the surface facing the bottom opening 19) of the rear lid 39. A pair of guided pins 81 that are inserted into the pair of guide grooves 31 protrude toward the sides of the rear lid 39 at the distal ends of the pair of bracket parts 80 .

By the way, at the lower end of the front lid 37, as shown in FIG.
As shown in FIGS. 9 and 10, an edge plate part 84 is formed, and normally this edge plate part 84 closes a part of the front side of the bottom opening 19 as shown in FIG. The lower end edge of the edge plate portion 84 comes into contact with the inner surface of the tip portion of the edge plate portion 84 to define a space between the front opening 18 and the bottom opening 19 . The inner surface of the tip end of the edge plate part 84 forms an inclined surface 85 as shown in FIGS.
The front cover 37 can be opened smoothly without getting hit by the lower edge of the front cover 37.

The details of the front cover 37, upper cover 38, and rear cover 39 have been described above. When assembling these, first the rear cover 39 is attached to the upper cover 38, and then the upper cover 38 is attached to the front cover 37. Then, the front cover 37 and the torsion coil spring 58 are attached to the pair of bracket parts 36 of the upper half 2 from the direction of arrow b as shown in FIG. At this time, the pair of guided pins 81 of the rear lid 39 are inserted into the pair of guide grooves 31 from their upper ends.

Further, as shown in FIGS. 3, 4, 8, 11, and 12, the front surface of the cassette case 1 has a pair of left and right tape pulls that are continuous with both left and right ends of the front opening 18. An outlet 90 is provided. These two tape outlet ports 90 are connected to the upper and lower halves 2, respectively.
3, a pair of left and right bracket portions 36 and side walls 3b
and the tape guide surface 32 and the guide surface 2 integrally formed on the lower surface of the upper wall 2a of the upper half 2.
4 and a pair of left and right guide walls 91. And these two tape outlet ports 90
The upper edge 92 of the opening is at both left and right ends of the front edge of the upper wall 2a of the upper half 2 where the upper opening 20 is formed as described above (the inclined surface 70 is formed on this front edge). It is formed by the section. Then, the tape 10 wound around both tape reels 8 and 9 and stored in the cassette case 1 is pulled out from both tape outlet ports 90 to the front of the cassette case 1 and hung along the front opening 18. It has been passed.
As mentioned above, both tape guide surfaces 32 having a cylindrical shape can be used to guide the tape 10 at both left and right ends of the front opening 18.
I am guiding you.

However, when levering, Figures 8, 11 and 12
As shown in the figure, the opening upper edges 92 of both tape outlet ports 90 are located at the rear of the cassette housing 1 than the opening inner edge 93, which is the front end surface of the guide wall 91 having both tape guide surfaces 32 of both tape outlet ports 90. It is set at a position offset to the side by a predetermined distance l.

Next, the operating conditions of the tape cassette constructed as described above will be explained. As shown in FIG. 9, the tape cassette normally has a tape 10 stretched along the front opening 18, with the front side connected to the front cover 37, the back side connected to the rear cover 39, and the upper end connected to the upper cover 38. They are each covered and occluded by. Therefore, in this state, there is no risk that the tape 10 will be damaged by dust or the like, and the tape cassette is extremely reliable. At this time, a pair of fulcrum pins 76 provided at the upper end of the rear lid 39,
77 is pivotally supported by a pair of pin holes 75 of a pair of bracket parts 74 adjacent to the rear edge of the upper lid 38, and the lower end of the rear lid 39 is connected to an edge plate part 84 provided at the lower end of the front lid 37. Since they are in contact with each other, the rear cover 39 diagonally crosses the space between the front opening 18 and the bottom opening 19, and a somewhat wide space 108 is formed behind the tape 10. Therefore, even if the front cover 37 and the rear cover 39 are closed with the tape 10 slightly slack, the tape 10 will not close the front cover 37 and the rear cover 39.
There is no risk of damage caused by.

In addition, in the above-mentioned closed state, both lock claw bodies 4
The claw portions 52 of No. 6 engage with both lock holes 60 on both side plate portions 37a of the front lid 37, thereby preventing the front lid 37 from being opened inadvertently.

On the other hand, when the tape cassette is inserted into the video tape recorder body, the front cover 37 rotates upward and the top cover 38 slides rearward and upward, as shown in FIG. 10, and the rear cover 39 rotates upward. Move backward while moving. Therefore, the front and back sides of the tape 10 are open. That is, when a tape cassette is horizontally inserted into, for example, a cassette holder of a video tape recorder main body, a pair of left and right lock release pieces 62 provided on the cassette holder etc., release the front cover from the direction of arrow j as shown in FIG. 37 is relatively inserted into the pair of left and right slits 61. Then, the lock release pieces 62 press the inclined portions of the claw portions 52 of the lock claw bodies 46, and the engagement between the claw portions 52 and the lock holes 60 is released.

Next, when the tape cassette is moved downward in FIG. 9 and horizontally installed in the cassette mounting position, the pair of left and right positioning pins 16 provided at the cassette mounting position are inserted into both positioning holes 17 as shown in FIG.
The tape cassette is then positioned. In addition, the front lid 37 is pushed up by a pair of left and right protrusions 109 provided at the cassette mounting position.
The front cover 37 rotates upward against the pair of torsion coil springs 58 and the pair of tension springs 73, as shown in FIGS. 2 and 10. At this time, the upper lid 38 slides rearward and upward as shown in FIG. 10 while the sloped surface portions 74a of the pair of left and right bracket portions 74 are guided by the sloped surface 70 of the upper half 2, and finally the upper half 2 Climb onto the top of the. Also, the rear lid 3
9, the pair of left and right guided pins 81 are in both guide grooves 3.
1 and is pulled diagonally upward by the sliding movement of the top cover 38, so it moves rearward while rotating upward. Therefore, at this time, the lower end of the rear cover 39 rises while drawing a gentle circular arc trajectory that is almost vertical, so that the lower end of the rear cover 39 does not come into contact with the back surface of the tape 10. As shown in FIGS. 4, 5, and 9, the pair of left and right tension springs 73 are normally located on the sides of the pair of left and right tape guide sections 32, but when a cassette is attached, the
As shown in Figure 0, the tape escapes upward, so when the tape is pulled out using the loading pin 95, which will be described later,
A pair of tension springs 73 are pulled out from the tape 10
It won't get in the way.

The front lid 37, the upper lid 38, and the rear lid 39 are opened as described above, but since the upper lid 38 and the rear lid 39 are opened in conjunction with the opening operation of the front lid 37, the upper lid There is no need to provide any special projections or the like at the cassette attachment position for opening the rear lids 38 to 39. In addition, the front lid 37, the upper lid 38, and the rear lid 3
9 is in a horizontal state above the tape cassette as shown in FIG. 10 when the lid is opened. Therefore, the tape cassette according to this embodiment can improve the space factor at the cassette mounting position, and is suitable for downsizing video tape recorders.

By the way, as is well known, when a tape cassette is installed horizontally from above at the cassette installation position in the video tape recorder main body, a pair of left and right loading pins 95 etc. are attached to the front of the cassette housing 1, as shown by solid lines in FIG. It is inserted relatively into the inside of the tape 10 being pulled out from the bottom opening 19, and then both loading pins 95 and the like are moved to the front of the cassette housing 1 as shown by chain lines in FIG. Therefore, the tape 10 is placed on both tape guide surfaces 3.
2 and pulled out to the outside of both tape outlet ports 90, and the pulled out tape 10 is loaded onto a predetermined tape running path.

At this time, the tape 10 is moved to the tape outlet 90 by moving the loading pin 95 and the like while maintaining the correct vertical position as shown by the solid line in FIG.
can be pulled out horizontally and correctly. However, due to the looseness of the loading pin 95, etc.
The loading pin 95, etc. that received the tape tension,
If the tape 10 is tilted in the direction of the arrow X (the upper end 95a is tilted backward) as shown by the chain line in FIG. Hey, tape 1
The upper edge 96 of the cassette housing 1 is likely to be pressed against the upper edge 92 of the opening of the tape outlet 90 of the cassette housing 1 and easily be damaged.

However, in the tape cassette according to the present embodiment, the upper edge 92 of the opening of the tape outlet 90 is set at a position offset by a distance l rearward than the inner edge 93 of the opening, so that the tape 10 is Even if it is moved upward (in the direction of arrow Y), the tape 1
The upper edge 96 of the tape 10 is not pressed against the upper edge 92 of the opening, and damage to the upper edge 96 of the tape 10 can be prevented.

Note that when removing the tape cassette described above from the main body of the video tape recorder, the front cover 3
7. The operating conditions of the upper cover 38 and the rear cover 39 are completely opposite to those described above. That is, the front lid 37 is rotated in the closing direction by a pair of torsion coil springs 58 and a pair of tension springs 73, and the upper lid 38 and the rear lid 39 are respectively closed in conjunction with the rotation of the front lid 37. .
Note that the pair of torsion coil springs 58 are not necessarily necessary when the rotation moment of the top cover 38 by the pair of tension springs 73 is increased;
can also be rotated in the closing direction using only the pair of tension springs 73.

Although one embodiment of the present invention has been described above, the present invention is not limited to the structure shown in the above embodiment, and various modifications are possible. Further, the present invention is applicable not only to tape cassettes for video tape recorders, but also to tape cassettes for various other information processing devices.

As described above, the present invention includes integrally providing at least one locking protrusion in a position close to at least one fulcrum pin of the front cover, and attaching a torsion coil spring to the outer periphery of the one fulcrum pin by means of the coil portion. By inserting the torsion coil spring and locking the end of the torsion coil spring in the convex portion, the torsion coil spring is temporarily fixed to the front cover, and the temporarily fixed torsion coil spring is attached to the cassette case together with the front cover. This is a tape cassette constructed as follows.

Therefore, according to the present invention, when assembling the front cover to the cassette case, the torsion coil spring can be temporarily fixed to the outer periphery of the fulcrum pin of the front cover in an extremely stable manner. The torsion coil spring does not change its direction or easily fall off, and the front cover and the torsion coil spring can be assembled very easily. And yet,
Since the spring locking convex portion is simply provided integrally with the front cover, the structure and manufacturing are extremely simple.

[Brief explanation of the drawing]

The drawings show an embodiment in which the present invention is applied to a tape cassette for a video tape recorder, in which Fig. 1 is a perspective view of the tape cassette when it is not installed, and Fig. 2 is a perspective view of the same when the tape cassette is installed. Figure 3 is an exploded perspective view of the same as the above, Figure 4 is a plan view of the same as the above, Figure 5 is a bottom view of the same as the above, Figure 6 is a perspective view of the front cover, upper cover and rear cover, and Figure 7 is the upper cover. Fig. 8 is an exploded perspective view showing an enlarged front part of the tape cassette, and Fig. 9 is a perspective view for explaining the installation situation of the tape cassette.
10 is a sectional view showing the same lid opened as above, FIG. 11 is an enlarged plan view of the tape outlet of the tape cassette, and FIG. 12 is FIG. 11 XII-XII. It is a sectional view taken along the line. In addition, in the symbols used in the drawings, 1...Cassette housing, 18...Front opening, 37...Front cover,
37a... Side plate part, 41... Fulcrum pin, 56...
Spring locking convex part, 57... Spring locking convex part, 58
...Torsion coil spring, 58a... End of torsion coil spring, 58b... End of torsion coil spring, 58
c...A coil portion of a torsion coil spring, 59...A spring locking portion.

Claims (1)

[Claims] 1 A pair of fulcrum pins are integrally provided inside the pair of left and right side plates of the front cover, and this front cover is rotatably attached to the cassette casing by means of the pair of fulcrum pins, and the rotation of the front cover causes the above-mentioned In the tape cassette, the front of the cassette case is configured to open and close, and a torsion coil spring is attached to the inside of at least one side plate of the front cover, and the torsion coil spring biases the front cover to close. , at least one spring locking protrusion is integrally provided on the front cover at a position close to the at least one fulcrum pin, and the torsion coil spring is inserted into the outer periphery of the one fulcrum pin by the coil portion. and temporarily fix the torsion coil spring to the front cover by locking the end of the torsion coil spring to the convex portion,
A tape cassette characterized in that the temporarily fixed torsion coil spring is attached to the cassette casing together with the front cover.