JPH0447814Y2 - - Google Patents

Description

[Detailed Description of the Invention] A. Field of Industrial Application The present invention relates to a tape cassette, particularly a tape cassette for a video tape recorder (VTR).

B. Prior art Conventionally, in tape cassettes for VTRs,
A lid stopper serving as a locking member provided on the lower half locks the opening/closing lid on the front surface of the upper half. When in use, the lid stopper is rotated to the unlocked position by the release pin on the VTR body, and at the same time the stopper claw is removed from the upper half lid, allowing the lid to be rotated to the open position. and tape loading begins.

In this case, the lid stopper is always elastically biased toward the locked position by, for example, a metal leaf spring attached to the lower half, so the unlocking operation is performed against the elastic force of this leaf spring. It will be done. Since this unlocking and locking operation is repeated, it is required that the mounting state of the leaf spring is stable and highly reliable.

However, in conventional cassettes, it is not so easy to install the leaf spring, and its point of action (i.e., the point of contact with the lid stopper) is located far away from the point of application of external pressure for unlocking the lid stopper. In addition, the spring force against the external pressure is insufficient, and therefore the locked state cannot be maintained reliably.

C. Purpose of the invention An object of the present invention is to provide a tape cassette having a locking mechanism with a spring that exerts sufficient spring force and allows easy and stable mounting.

D. Structure of the invention That is, in the present invention, the front closing lid is locked by the lock claw of the locking member provided on the lower half engaging with the engagement recess of the opening/closing lid on the front surface of the upper half. In a tape cassette in which a lock release protrusion for releasing the lock member is provided on the lock member at a location different from the lock pawl, the elastic material is free to urge the lock member to the lock position. an engaging wall portion whose end side is in elastic contact with the locking member in a line-like contact at a position corresponding only to the vicinity of the protrusion, and whose proximal end side of the elastic material is formed on the lower half; The tape cassette is attached so as to be engaged with the lower half, and in this attached state, the elastic material is in contact with the bottom surface of the lower half over its entire length.

E. Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows the lower half of a VTR tape cassette, and FIG. 2 shows the upper half of the same cassette. Between the take-up reel 2 and the supply reel 3 of the lower half 1, the magnetic tape 5 wound on the supply reel 3 side is joined to the leader tape 4 on the take-up reel 2 side by a splice tape 6. Ru. This joining position is not necessarily limited to the illustrated position. In the figure, 7 is a guide pole, 8 is a tape restraining flap, 9 is a tape guide, and 10 is a guide roller. In addition, in the upper half 11, reel 2
Transparent windows 12 and 13 are provided corresponding to and 3,
Furthermore, an opening/closing lid 14 that covers the front side of the lower half 1 is attached. As shown in FIG. 2, the opening/closing lid 14 is kept in a normally closed state by a coil spring 16 attached to a protrusion 15 on one end side and in contact with the inner surface of the upper half. In FIG. 1, the opening/closing lid 14 is shown by a chain line.

In the above, the opening/closing operation of the opening/closing lid 14 with respect to the front surface of the lower half 1 is performed as shown in FIGS. 3 to 5.

As clearly shown in FIG. 3, a locking mechanism 17 for the opening/closing lid 14 is provided at one end of the front side of the lower half 1. This locking mechanism consists of a locking member 10 consisting of a rotatable lid stopper having pivot shafts 18 and 19 engaged with the wall of the lower half, and a spring (plate spring) fixed to the lower half.
21 is elastically biased toward the lock position. The locking member 20 includes a locking pawl 22 for locking the opening/closing lid 14 and a protrusion 23 for unlocking.
are formed integrally with the through holes 24 and 25 in the lower half wall portion, respectively, passing through with a margin (see FIGS. 4 and 5).

The fixed end 21a of the leaf spring 21 is connected to the lower half 1.
The free end 21b is inserted and fixed into the engagement groove 27 formed by the wall portion 26 of the lock member 20, and the free end 21b is attached to the lock member 20 at a position near the lock release protrusion 23 of the lock member 20 (i.e., the external pressure application point for unlocking). It is forced to abut. This leaf spring 21 is provided in contact with the bottom surface of the lower half 1 over its entire length.
That is, the leaf spring 21 has its free end 21b in elastic contact with the lock member 20 at a position corresponding only to the vicinity of the protrusion 23 of the lock member 20, such as in a line contact. And in the locked state,
As shown by solid lines in FIGS. 3 to 5, the locking pawl 22 of the locking member 20 locks into the engaging recess 28 of the opening/closing lid 14.
Since the opening/closing lid 14 is stuck inside, the opening/closing lid 14 cannot be opened. However, when the lock release pin (not shown) on the VTR body presses the protrusion 23 in the direction of arrow 29, the leaf spring 21 is released as shown by the imaginary line in FIG.
The locking member 20 rotates counterclockwise against the spring force, and at the same time, the locking pawl 22 is disengaged from the engagement recess 28 of the opening/closing lid 14 as shown by the imaginary line in FIG. As a result, the opening/closing lid 14 is unlocked and rotated upward at the front surface of the lower half, as shown by the arrow 30 in FIG. 5, to be in the open state.

As described above, according to this embodiment, the leaf spring 21 as a locking (lid stopper) spring is arranged as shown in the figure, and its action position 21b is set near the external pressure application point (i.e., the protrusion 23). Therefore, sufficient elastic resistance force or spring force against external pressure can be generated. Therefore, even if the leaf spring is the same, its operating position can be changed to, for example, lock pawl 2.
Compared to the case of position 2 or further forward, the spring action of the leaf spring can be effectively exerted, so the locked state can be maintained well and reliability is increased.

Moreover, the leaf spring 21 itself is connected to the lower half wall portion 26.
It can be easily attached by simply inserting (or dropping) into the engagement groove 27, making the attachment work very easy. Moreover, since the leaf spring 21 is in contact with the bottom surface of the lower half over its entire length,
The mounting state is stable, and its elastic deformation is always constant and reliable.

In addition, since the leaf spring 21 undergoes elastic deformation not only on the free end 21b side but also on the fixed end 21a side, the amount of deformation at each part is not very large, making it difficult for fatigue to occur during repeated use. ing.

FIG. 6 shows an embodiment of the present invention.

In this example, compared to the example shown in FIG.
The shape of the fixed side is different, and the wall portion 26 forming the engagement groove 27 is formed with an inclined side 31 facing the locking member 20, and the leaf spring 21 is attached along this inclined side.
is bent into an acute angle. By this, leaf spring 2
This makes it difficult for the elastic deformation of 1 to occur, and the locked state can be more firmly maintained.

Next, still another embodiment of the present invention will be described.

According to this example, the lid stopper spring 21 is made of plastic, particularly polyethylene terephthalate (PET), instead of metal as in the examples of FIGS. 1-6.

Not only can this PET spring produce sufficient spring force, but it is also advantageous over metal springs in that the spring itself can be easily manufactured by punching. The manufacturing method may be molding, and various shapes can be easily created. Moreover, not only PET but also other plastics (eg, polycarbonate) can be used.

Although the present invention has been illustrated above, the above-mentioned example can be further modified based on the technical idea of the present invention.

For example, the shape and position of the lid stopper spring, as well as the shape and structure of the locking member, may be changed in various ways. Furthermore, the method of mounting the spring is not limited to the above-mentioned method.

F. Effects of the Invention As described above, in the present invention, the acting position of the spring is located near the point of application of external pressure on the locking member, so that a sufficient elastic resistance force or spring force against external pressure can be generated. Therefore, since the spring action of the same leaf spring can be effectively exerted, the locked state can be maintained well and reliability is increased. Since the free end side of the resilient material that urges the locking member to the locking position is brought into elastic contact with the locking member at a position corresponding only to the vicinity of the protrusion, like a line contact, the locking member The locking properties are good, and in particular, there is little risk of the locking member being accidentally released, and there is little risk of damaging the tape. In addition, no torsional force is applied to the lock member, and the lock member is less likely to be deformed, so that a situation where the lock is not released even after the lock release operation is performed will not occur. In addition, the spring itself can be easily installed by simply engaging with the engagement wall of the lower half, making the installation process very easy. Furthermore, since the above spring is in contact with the bottom surface of the lower half over its entire length,
The mounting state is stable, and its elastic deformation is always constant and reliable.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which FIG. 1 is a plan view of the lower half of the tape cassette, and FIG.
The figure is a plan view of the upper half of the same tape cassette, the third
The figure is an enlarged view of the main part of Figure 1, and Figure 4 is the - of Figure 3.
A line sectional view, FIG. 5 is a - line sectional view of FIG. 3,
FIG. 6 is a plan view similar to FIG. 3 according to another example. In addition, in the symbols shown in the drawings, 1, 11...
Half, 2, 3...Reel, 5...Magnetic tape,
14... Opening/closing lid, 20... Lock member (lid stopper), 21... Leaf spring, 22... Lock claw,
23...Protrusion, 26...Lower half wall, 27...
Engagement groove, 28... engagement recess, 29... external pressure.

Claims (1)

[Scope of utility model registration request] The locking claw of the locking member provided on the lower half engages with the engagement recess of the opening/closing lid on the front surface of the upper half, thereby locking the opening/closing lid, and releasing the lock from the locking member. In a tape cassette in which a protrusion is provided on the locking member at a location different from the locking pawl, the free end side of the elastic material that urges the locking member to the locked position corresponds only to the vicinity of the protrusion. The resilient material is in elastic contact with the locking member in a linear manner, and the base end of the resilient material is attached to engage with an engagement wall formed on the lower half. A tape cassette characterized in that, in an attached state, the elastic material is in contact with the bottom surface of the lower half over its entire length.