JPH079747B2 - Tape car ledge - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a tape cartridge having a front lid on the front side of a main body case, and an improvement in a lock mechanism for holding the front lid in a closed posture when not in use. It was added.

[Conventional technology]

As a prior art of this type of tape cartridge, the present applicant has previously proposed an unpublished tape cartridge shown in FIGS. 6 to 11 (Japanese Patent Laid-Open Nos. 63-276772 and 63-281289).
issue).

As shown in FIG. 6, reels 3 and 4 around which a tape 2 is wound are rotatably arranged on the left and right sides of a main body case 1 formed by abutting a plastic upper case 1a and a lower case 1b. 2 is fed from one reel 3 to a tape loading pocket 5 on the front side of the case and wound on the other reel 4. And body case 1
A front lid 6 for pivotingly opening and closing the front cover 6 for covering and protecting the front outer side of the tape 2 when not in use is rotatably openable and closable.

In FIG. 8, the left and right side pieces 6b, 6b of the front lid 6 are pivotally attached to the upper case 1a via a horizontal shaft 7.7, and the front lid 6 is rotated around the shaft 7 to open and close. A torsion coil spring 8 is attached to one of the horizontal shafts 7, one end of which is engaged with the front lid 6 side and the other end of which is engaged with the upper case 1a side, so that the front lid 6 is always urged to rotate in the closing direction. Has been done. As shown in Figure 10,
On the inner surface side of the one side piece 6b of the front lid 6, there is provided a recess 21 having an engaging surface 21a with which a lock claw 13 of a lock plate 10 described later is engaged and disengaged.

In FIGS. 7 and 8, a lock plate 10 for holding the front lid 6 in a closed posture is provided on the inner surface of one side wall 9 of the main body case 1 in a narrow space in front of the central portion of the side wall 9 in the front-rear direction. It is stored in the space.

In FIG. 11, the lock plate 10 is a plastic molded product, and has a base 11 made of a flat rectangular plate having a relatively wide vertical and front-rear direction and a bendable extension extending forward from the upper front end of the base 11. It consists of a large arm 12. Then, a lock claw 13 is provided on the tip of the arm 12 so as to project outward,
A pyramid-shaped release protrusion 14 is provided on the outer surface side of the lower part of the protrusion 11 so as to
A groove 15 is formed in a part of the upper edge of the base 11 so as to be located right above the release projection 14.

On the other hand, in FIG. 7 and FIG. 8, an opening 16 is provided in a part of the side wall 9 of the upper case 1a where the lock plate 10 is housed, and the position regulating rib 18 is provided on the inner surface of the upper wall 17. Is provided so as to run in the thickness direction of the side wall 9 and to be located right above the opening 16. Also, from the inner surface of the upper wall 17,
19 is provided so as to project downward, and the spring receiving portion 19 and the side wall 9 are connected by a rib 20. The spring receiving portion 19 also serves as a boss for screwing the screw 23 when the upper case 1a and the lower case 1b are butted and fastened.

As shown in FIGS. 7 and 8, the lock plate 10 is installed along the inner surface of the side wall 9 of the upper case 1a, the release projection 14 is projected from the opening 16, and the groove 15 is slid on the position regulating rib 18. The lock claw 13 is engaged with the engaging surface 21a of the concave portion 21 of the front lid 6 while being movably fitted. A spring member 22 composed of a V-shaped leaf spring is interposed between the base portion 11 and the spring receiving portion 19 of the lock plate 10, and the lock plate 10 is constantly moved by this spring force.
It is urged to move to the lock position along the inner surface of the
The projecting state and the engaging state of the lock claw 13 are maintained.

In such a tape cartridge, as a method of unlocking the front lid 6, there are a method of pressing the release projection 14 of the lock plate 10 and a method of forcibly opening the front lid 6 from a certain opening angle with a constant force. .

In the former release method in which the release protrusion 14 of the lock plate 10 is pressed, the lock plate 10 is loaded into the VTR and the release protrusion 14 is completely pushed into the case by the release operation member (holder) on the VTR side.
Moves in parallel in the direction away from the inner surface of the side wall 9, and the lock claw 13 is disengaged from the recess 21 of the front lid 6. Subsequently, the front cover 6 is pushed upward by the front cover opening operation member on the VTR side and rotated upward.

Regarding the latter forced release method, when the front lid 6 is opened by a certain angle θ ₁ as shown in FIG. 8, the locking claw 13 causes the engaging surface of the concave portion 21 of the side piece 6b as shown in FIG. When it comes into contact with 21a and comes into a locked state, and then a forced release force F ₁ is applied,
As shown in FIG. 7, the moment M ₁ in the plate thickness t direction acts on the lock claw 13 and the arm 12 and bends to the position A of the chain double-dashed line in FIG. 7 to prevent the release projection 14 from being pushed in. It can be canceled automatically. This is a VTR
This is for compatibility with models that do not have a release member for releasing the release protrusion 14 on the side.

[Problems to be solved by the invention]

However, in the tape cartridge that allows forced release as described above, the forced release force F ₁ is large to some extent (however, V
The force that can be forcibly released in TR is less than f ₁ g), that is, F ₁ ≤f ₁ , F
It is desirable that ₁ ≈ f ₁ to obtain a stable and reliable locking function.

However, conventionally, the engaging surface 21a with which the lock claw 13 in the recess 21 of the front lid 6 abuts is inclined at the same angle as the forced release opening angle θ ₁ as shown in FIG. As shown in, the toe 13a of the lock claw 13 was formed vertically. Therefore, f force the locking pawl 13 as shown in FIG. 9 acts in the direction of the arrow, bending but moments M ₁ is to act, the lock plate at a small bending moment M ₁ that time
Arm 12 of 10 bends inward of the case, small force release force
The lock is released at F ₁ , and the lock effect is extremely low. Therefore, the front cover 6 may be easily opened when not in use.

In order to increase the forced release force F ₁ , the rigidity of the arm 12 I = bt ³ /
12 (b is the width of the arm 12 and t is the plate thickness of the arm 12) or the spring pressure of the spring member 22 needs to be increased, but the space for installing the lock plate 10 in the tape cartridge is required. Due to the restriction, the plate thickness t of the arm portion 12 cannot be made too large, and if the spring pressure is increased, the body case 1 is likely to be deformed by the spring pressure in a high temperature environment. There is a limit. Further, it is conceivable to mold the material of the lock plate 10 with engineering plastic to increase the rigidity, but this has the disadvantage of increasing the cost.

Therefore, in the present invention, the lock plate 10 having the lock claw 13 that can be engaged with and disengaged from the engagement surface 21a of the front cover 6 is provided on the side wall 9 of the main body case 1.
Is installed on the inner surface side of the front lid 6 and the front lid 6 has a certain opening angle θ ₁
It is an object of the present invention to improve the lock function by increasing the forcible release force of the front lid 6 in the tape cartridge which is forcibly opened at a position of with a constant force.

[Means for solving problems]

In the present invention, the shape of the lock claw 13 of the lock plate 10 is improved so as to increase the force of the front cover 6 forcibly released. That is, the engaging surface 21a of the concave portion 21 of the front lid 6 is formed vertically, while the toe 13a engaging the engaging surface 21a of the lock pawl 13 has an angle θ ₁ with which the front lid 6 is forcibly opened. By tilting at the same angle, the direction of the force acting on the lock claw 13 is changed and the arm 12
Increase the rigidity of. Further, the claw tip surface 13b facing the engagement surface 21a of the lock claw 13 is inclined in the plate thickness t direction of the arm 12, and the claw tip 13a engages with the lock claw 13 in point contact with the engagement surface 21a. The frictional force with the surface 21a is increased.

〔Example〕

1 to 5 show an embodiment of the tape cartridge according to the present invention.

Since the entire basic structure of the tape cartridge is the same as that described above, the same reference numerals are given, the description thereof is omitted, and only different points will be described.

First, in FIG. 3, the engaging surface 21a of the recess 21 of the front lid 6 is formed vertically. On the other hand, in the lock plate 10, as shown in FIGS. 1 and 5, the toe 13a of the lock claw 13 is tilted by the same angle as the angle θ ₁ at the forced release position of the front lid 6.

At this time, as shown in FIGS. 1 and 2, the engaging surface 21a of the lock claw 13 and the concave portion 21 of the front lid 6 has a forced release force F ₁ when the front lid 6 is tilted at an angle θ _1. To work. Therefore, the bending moment M due to the upward component force f'shown in FIG. The bending moment M is, M = M ₁ + M ₂ a section modulus Z _1, Z _2, if the bending stress _{σ, M 1 = σZ 1 Z} 1 = bt 2/6 M 2 = σ'Z 2 Z 2 = tb ^2/6 here, a t (plate thickness of the arm portion) <b (width of the arm portion).

From this relationship, in addition to the conventional bending moment M ₁ in the plate thickness t direction described above, the bending moment M ₂ acts in the upward direction by the bending moment M _{2 in the} width b direction, which increases the rigidity of the arm portion 12 and is difficult to bend. It turns out to be a thing.

Further, in FIG. 2, the claw tip surface 13b of the lock claw 13 facing the engagement surface 21a on the front lid 6 side is tilted by a predetermined angle θ _{2 with} respect to the plate thickness t direction of the arm portion 12, and Toe 13a
Are point-contacted by the engaging surface 21a. As a result, the frictional force between the lock claw 13 and the engagement surface 21a can be increased, and the forced release force F ₁ can be further increased.

〔The invention's effect〕

According to the present invention, since the are is inclined at an opening angle theta ₁ with the same angle of a forced release position the toe 13a front lid 6 of the locking pawl 13 for locking plate 10, the front lid 6 from the open-out angle theta ₁ When it is forcibly opened, a bending moment acts on the arm 12 of the lock plate 10 not only in the plate thickness direction but also in the width direction, and the rigidity of the lock claw 13 in the bending direction (plate thickness direction) can be improved. It was Further, since the claw tip surface 13b of the lock claw 13 facing the engagement surface 21a on the front lid 6 side is inclined in the plate thickness t direction of the arm portion 12 to bring the toe 13a into point contact with the engagement surface 21a,
The frictional force between the lock claw 13 and the engagement surface 21a could be improved. Therefore, even when the arm portion 12 of the lock plate 10 is formed of an inexpensive plastic material such as polyacetal, it is difficult to bend, and the forced release force F ₁ of the front lid 6 is improved several times as compared with the conventional _one described above. Since the lock function is improved, it is possible to prevent accidental opening of the front lid 6.

[Brief description of drawings]

1 to 5 show an embodiment of a tape cartridge according to the present invention. FIG. 1 is a side view of a lock claw of a lock plate, and FIG. 2 is a lock claw on an engaging surface of a front lid. Fig. 3 is a plan view showing the engaged state, Fig. 3 is a partial side view, and Fig. 4 is a vertical sectional side view showing the state in which the front lid is opened to the forced release position.
FIG. 5 is a perspective view of the lock plate. 6 to 11 show a conventional tape cartridge. FIG. 6 is an internal plan view of the whole, FIG. 7 is a plan view of essential parts, FIG. 8 is a partial side view, and FIG. The figure is a vertical sectional side view showing the state in which the front lid is opened to the forced release position, FIG. 10 is a perspective view showing the concave portion of the front lid, and FIG. 11 is a perspective view of the lock plate. 1 ... Main body case, 6 ... Front lid, 7 ... Horizontal axis, 9 ... Side wall, 10 ... Lock plate, 13 ... Lock claw, 13a ... Toe tip, 13b ... Claw tip surface, 14 ... Release Projection, 21 ... Recess, 21a ... Engaging surface.

Claims (1)

[Claims] 1. A front cover 6 is mounted on the front side of a main body case 1 so as to be openable and closable about a horizontal axis 7, and the front cover 6 is held in a closed posture on the inner surface side of a side wall 9 of the main body case 1. A lock plate 10 is arranged. The lock plate 10 is disengaged from a flexible arm 12 and an engagement cotton 21a provided at the tip of the arm 12 perpendicularly to the inner surface of the side piece 6b of the front lid 6. The front lid 6 has a free locking claw 13 so that the front cover 6 is forcibly opened with a constant force even when the locking claw 13 is engaged with the engaging surface 21a at an opening position of a certain angle θ _1. The toe 13a of the lock claw 13 that comes into contact with the engaging surface 21a has the angle θ
The claw tip surface 13b of the lock claw 13 is inclined by ₁ and the claw tip surface 13b of the lock claw 13 facing the engagement surface 21a is pointed to the engagement surface 21a. A tape cartridge characterized in that