JPS6220932Y2 - - Google Patents

Description

[Detailed description of the invention] This invention provides a magnetic tape cartridge that has a front lid closing lock mechanism for tape protection and a reel brake mechanism that prevents rotation of the tape reel. The main objective is to improve the mounting method of the torsion spring, which is one of the members constituting the lid lock mechanism and the reel brake mechanism, and to eliminate assembly defects of the torsion spring.

That is, in the video magnetic tape cartridge shown in FIGS. 1 and 2, when the cartridge is not in use, the tape protection front cover 4 attached to the front of the case is locked closed, and the tape mounted inside the case is locked. When the reel 2 is prevented from rotating and loaded into the video camera, the closing lock of the front lid 4 and the reel brake are both released in conjunction with each other.

As a structure for this purpose, two support shafts 7 and 8 are installed vertically from the inner bottom surface at the front right corner of the main body case 1, and a stopper 9 for the reel brake is installed on one support shaft 7, and a stopper 9 for the reel brake is installed on the other support shaft 8. A lock plate 10 for locking the front cover is fitted and supported horizontally rotatably, and a loop portion 11 of a torsion spring 11 is attached to one support shaft 7.
A is fitted from above, one end 11b thereof is abutted and locked to a spring receiver 24 provided on the stopper 9, and the other end 11c is abutted and latched to a spring receiver 25 provided on the lock plate 10, Torsion spring 11
Stopper 9 and lock plate 1
0 to the lock position.

The problem is the torsion spring 11, its both ends 11b,
The problem is how to set the shape of the spring receivers 24 and 25 that receive the springs 11c.

That is, as a property of the torsion spring 11, its loop portion 11a is fitted onto the vertical shaft, and its both ends 11
When b and 11c are extended horizontally and brought into contact with other objects in a free state, one end portion 11b protruding from the upper end of the loop portion 11a is directed upward toward the loop portion 11a.
The other end portions 11c protruding from the lower end of are each trying to shift downward.

However, in the past, the torsion spring 11 has tended to be installed without fully recognizing its general properties, and each end of the torsion spring 11 has been attached to each spring receiving portion 24, 25 of the stopper 9 and the lock plate 10. All that was required was a means to prevent the parts 11b and 11c from coming off upward. Therefore, from the viewpoint of ease of assembly in a narrow space, the one end 11 protruding from the upper end of the loop portion 11a of the torsion spring 11 is
b is often brought into contact with and locked in the spring receiving part 24 of the stopper 9, but in that case, the spring receiving part 25 of the lock plate 10 receives the other end 11c protruding from the lower end of the loop part 11a of the torsion spring 11. No special means was taken to prevent the other end portion 11c from shifting downward. As a result, the fact that the straight line distance between the support shaft 7 on which the loop portion 11a of the torsion spring 11 is mounted and the spring receiving portion 25 on the lock plate side and the distance between the left and right sides of the two are extremely small in terms of space also has a large influence. Therefore, at the stage of assembling the torsion spring 11, the tip of the other end 11c protruding from the lower end of the loop portion 11a is already in a state in which the tip of the other end 11c is largely displaced below the spring receiving portion 25 and is stretched out against the vertical surface. When the front cover 4 is attached to the front cover 4, the spring pressure becomes abnormally high and the lock plate 10 cannot be smoothly moved back to the unlocked position inside the case. It was happening.

This inconvenience is caused by the fear that if the torsion spring 11 is subjected to an impact even after being assembled, the other end 11c will easily shift downward.

This invention eliminates such conventional drawbacks and prevents the torsion spring from exhibiting a poor installation condition not only during assembly but also after assembly, and thereby locking the front lid and the brake of the tape reel. The final purpose is to interlock the two to ensure effective and reliable operation.The main feature of this system is that it uses a torsion spring whose winding direction is specified for the loop part, and a stopper and lock that receive both ends of the torsion spring. Specify the shape of each spring receiving part with the plate, and then one end protruding from the top end of the loop part of the torsion spring is brought into contact with the spring receiving part set up on the stopper to prevent it from coming off upwards. The other end protruding from the lower end of the loop portion is brought into contact with and locked to a spring receiving portion provided upright on the lock plate while preventing downward displacement.

The details will be explained below based on the drawings.

1 and 2 illustrate certain types of video magnetic tape cartridges. The main case 1 of this is plastic upper and lower cases 1a and 1b.
tape reels 2, 2 are rotatably installed on the left and right sides of the tape reels 2, 2, and both ends of the magnetic tape 3 are latched and connected to both reels 2, 2, respectively. Magnetic tape 3 is on one reel 2
It is fed out, passes through the front of the case, and is wound onto the other reel 2.

Reference numeral 4 denotes a front cover for covering and protecting the magnetic tape 3 led out to the front of the case when not in use, and the front cover 4 has left and right sides 4a, 4a that can be pivoted to open and close in front of the upper case 1a. Of the left and right pivot shafts 5, 5, the lid is urged to close by a spring 16 wound around the left pivot shaft 5 in the figure.

At the top right corner of the lower case 1b, there is a means for applying a brake to the tape reel 2 on the right side and a front cover 4.
A means for locking the lid is incorporated.

That is, two support shafts 7 and 8 are vertically erected from the corresponding portions of the bottom wall 6 of the lower case 1b, and a stopper 9, a lock plate 10, and a torsion spring 11 are assembled to these support shafts 7 and 8, respectively. It is attached.

The stopper 9 has a vertically long cylindrical boss 12, and the boss 12 is fitted onto one of the support shafts 7 from above so as to be horizontally rotatable. And behind boss 12,
An engagement piece 1 whose tip engages with square engagement teeth 13 continuously formed on the outer periphery of the lower flange 2a of the tape reel 2
4 are connected in series, and in front of the boss 12 is connected an operating piece 15 whose tip is bent into an L-shape.

The lock plate 10 has a vertically elongated cylindrical boss 17 at the rear end, and the boss 17 fits into the other support shaft 8 from above so as to be horizontally rotatable.
It is disposed along the right side wall portion 18 recessed inward of the case in front of the case b, and has an engaging protrusion 19 at the tip.
is installed protrudingly. The engaging protrusion 19 projects out of the case through a hole 21 formed in the right side wall portion 18, and its protruding end is fitted into an engaging hole 22 provided on the right side 4a of the front cover 4. .

After the torsion spring 11 is fitted with the stopper 9 on the support shaft 7, the loop portion 11 of the torsion spring 11 is attached to the upper end of the support shaft 7.
a is fitted, and one end 11b protruding from the upper end of the loop portion 11a abuts and locks on the spring receiver 24 which is vertically connected and raised from the engagement piece 14 of the stopper 9, and the lower end of the loop portion 11a The other end 11c coming out from
is abutted against and locked to a spring receiving part 25 which is vertically connected and raised from near the base end of the lock plate 10.

In this case, when the magnetic tape cartridge is not in use, the elastic force of the torsion spring 11 causes the stopper 9 to move its engagement piece 14 to the right tape reel 2.
The lock plate 10 is pressed to a position where it engages with the engagement teeth 13 of the lock plate 10, and the lock plate 10 also engages with the engagement protrusions 19 thereof.
is pressed to the lock position where it engages with the engagement hole 22 of the front cover 4, the brake is applied to the tape reel 2, and the front cover 4 is brought into a closed and locked state.

Furthermore, a brake means for preventing rotation of the left tape reel 2 when the magnetic tape cartridge is not in use is also incorporated in the front left corner of the lower case 1b. That is, a support shaft 27 and a spring bearing pin 28 are vertically provided in the case bottom wall 6 at the corresponding part, and a stopper 9 and a torsion spring 30, which are substantially the same as those described above, are attached to the support shaft 27, respectively. Supported. However, the loop portion 30 of the torsion spring 30
One end 30b protruding from the upper end of the loop part 30a is brought into contact with and locked to the spring receiving part 24 connected to the engaging piece 14 of the stopper 9, while the other end 30c protruding from the lower end of the loop part 30a It is abutted and supported by the receiving pin 28, and this point is slightly different from the method of hanging the torsion spring 11 described above.

Next, assume that a magnetic tape cartridge is loaded into the video camera. Operation member 32 on the video unit side
As shown in FIG. 3, the lock plate 10 enters the notch 33 provided at the front right end of the lower case 1b and hits the inclined surface 10a at the tip of the lock plate 10, thereby locking the lock plate 10 into the lock on the inside of the case. It is moved back to the release position against the torsion spring 11. With this, the closing lock of the front cover 4 is released, and the front cover 4 rotates upward about the pivot shafts 5, 5 against the spring 16 and opens. As the front cover 4 is opened, the protrusions 34, 34 provided on the two rotating pivot shafts 5, 5 move as shown in FIG.
5 and 15 to push each operating piece 15 forward against the torsion spring. As a result, each stopper 9 rotates around the support shaft, and its engaging piece 14 disengages from the engaging teeth 13 of each tape reel 2, releasing the reel brake.

Note that when the upper case 1a is placed on the lower case 1b, members provided on the inner surface of the upper case 1a fit into each of the above-mentioned support shafts 7, 8, and 27, respectively. This is intended to prevent the mated assembly members from coming off.

The magnetic tape cartridge to which this invention is directed is basically constructed as described above, but the main point of this invention lies in what will now be described.

First, a retaining surface 35 is formed protrudingly on the spring receiving surface side of the spring receiving portion 24 of the stopper 9, and the retaining surface 35 abuts and prevents one end 11b of the torsion spring 11 from coming off upward. It was designed to be received and supported in a substantially horizontal position. Next, lock plate 10
On the spring receiving surface side of the spring receiving part 25, a retaining surface 36 is formed upwardly and a retaining surface 37 is protrudingly formed downwardly.
The retaining surface 37 prevents the other end 11c of the screw from shifting downward. The other end of the spring 11c is received and supported between the spring 36 and the receiving surface 37 in a substantially horizontal position.

In such a case, if the other end 11c of the torsion spring 11 is made long, the tip will interfere with the support shaft 8, so it has to be made short. As long as this is done, there will be no downward displacement during and after assembly, so that it can be guided diagonally to the spring receiving portion 25 and reliably received and supported in a substantially horizontal position.

In addition, one end 11b of the torsion spring 11 is sufficiently long, and the spring receiving part 24 of the stopper 9, which has a relatively large space, is provided with a retaining surface 35 to prevent the spring from coming off upward, so that it can be easily and reliably held in a substantially horizontal position. Since the torsion spring 11 can be received and supported by the torsion spring 11, it will not come off upward after being assembled.

In addition, the spring receiving part 25 on the lock plate side has the following:
As shown in FIG. 8, the spring receiving surface side may be partially recessed to form the aforementioned retaining surface 36 and receiving surface 37 above and below. Similarly, in the spring receiving portion 24 of the stopper 9, the spring receiving surface may be recessed to form the retaining surface 35.

In summary, according to this invention, the torsion spring 1
1 can be reliably received and supported by the spring receiving part 24 of the stopper 9 and the spring receiving part 25 of the lock plate 10 in substantially horizontal positions, respectively. Therefore, this torsion spring 11 acts in contact with the stopper 9 and the lock plate 10 with an appropriate pressure, and the stopper 9 brakes and releases the tape reel 2, and the lock plate 1
It has now become possible to effectively and reliably lock and release the front cover 4 by using the zero key.

[Brief explanation of the drawing]

The drawings illustrate a magnetic tape cartridge according to the present invention, and FIG. 1 is a schematic perspective view of the entirety, and FIG.
The figure is a plan view showing the overall internal structure, Figure 3 is an enlarged plan view of main parts, Figure 4 is a view taken along line A-A in Figure 3, and Figure 5 is a view taken along line B-B in Figure 3. visual view,
FIG. 6 is a perspective view of the main parts, and FIG. 7 is a perspective view of a lock plate, which is one of the structural members of the present invention. FIG. 8 is a front view of a lock plate according to another embodiment of the present invention. 1...Main case, 1a...Upper case, 1b...
...lower case, 2...tape reel, 2a...lower flange of tape reel, 3...magnetic tape, 4...
...Front cover, 4a... Left and right sides of the front cover, 5... Pivot shaft of the front cover, 6... Bottom wall of the case, 7, 8... Support shaft,
9... Stopper, 10... Lock plate, 1
1...Torsion spring, 11a...Loop portion of torsion spring, 11b...One end of torsion spring, 11c...Other end of torsion spring, 12...Boss of stopper, 1
3... Engaging teeth provided on the tape reel side, 14...
Engagement piece, 15... Action piece, 17... Lock plate boss, 19... Engagement protrusion, 21... Hole provided on the side wall of the lower case, 22... Hole provided on the side of the front cover, 24...Spring receiving part of stopper, 25...
Spring receiving part of lock plate, 27... Support shaft, 28
... Spring receiving pin, 30 ... Torsion spring, 32 ... Operating member, 33 ... Notch, 34 ... Protrusion provided on the pivot shaft of the front cover, 35 ... Provided on the spring receiving portion of the stopper. 36... A retaining surface provided on the spring receiving part of the lock plate, 37... A receiving surface provided on the spring receiving part of the lock plate.

Claims (1)

[Scope of utility model registration request] The spring receiving part 24 of the stopper 9 is arranged in a substantially vertical manner, and one end 11b extending from the upper end of the loop part 11a of the torsion spring 11 is attached to the spring receiving part 24 substantially horizontally so as not to come off upward. The lock plate 1 is formed with a retaining surface 35 that receives and supports the lock plate 1 in its posture.
0 spring receiving portions 25 are vertically arranged in series, and the loop portions 11a of the torsion springs 11 are attached to the spring receiving portions 25.
A magnetic tape cartridge characterized in that a receiving surface 37 is formed to receive and support the other end portion 11c extending from the lower end in a substantially horizontal position so as not to shift downward.