JPH0411272Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a magnetic tape cassette, and more specifically, to a new compact cassette used for audio equipment of the same size or smaller than the Phillips type. It is something.

(Prior art) In recent years, cassette tape recorders have become smaller and lighter, and as a result, smaller magnetic tape cassettes have become popular, and audio technology is also becoming more compact and lightweight. - There is a strong demand for magnetic tape cassettes that allow long-time, high-quality recording and playback. Unlike analog methods, digital methods such as pulse code modulation (PCM), which record and reproduce input signals by converting them into pulses, are known as suitable for meeting these demands. Video tape cassettes, which are larger than compact audio tape cassettes, are generally in widespread use because of the need to widen the recording frequency band to about five times that of conventional audio tapes.

Except for special cases, these video tape cassettes are compatible with a rotary head system, and are provided with a guard panel that closes an opening provided in front of the cassette and can be opened above the cassette. In other words, when using a digital method,
Compared to conventional audio compact cassettes, in order to perform high-density, wide-frequency recording and reproduction, a cassette structure that takes sufficient measures to prevent dust and protect the tape is required.

The magnetic tape cassette that meets the above requirements, that is, the subject of the present invention, can be applied to audio equipment that uses a relatively wide frequency band recording and reproducing method, similar to the video tape cassette, and is large in size. This is an extremely small magnetic tape cassette that is intended for use with devices that are comparable to or smaller than conventional audio compact cassettes. Therefore, it is expected that this magnetic tape cassette will be carried and used outdoors as frequently as or more frequently than conventional audio compact cassettes, and that it will often be carried and used without a storage case. Therefore, a structure that is more dust-proof than conventional video tape cassettes has been desired.

Under these circumstances, various magnetic tape cassettes that meet the above requirements have been proposed. These magnetic tape cassettes, in addition to a guard panel that can be opened above the cassette like the video tape cassette described above, can also be slid in the front-rear direction of the cassette along the outer surface of the bottom of the cassette, and are constantly biased toward the front of the cassette. A slide guard is provided for closing the lower side of the opening, that is, the portion into which the tape pull-out member of the recording/reproducing apparatus enters.

This slide guard slides toward the rear of the magnetic tape cassette to open the opening when the magnetic tape cassette is in use, and in consideration of this function, it is provided in a shape that provides excellent sliding performance between the slide guard and the cassette body. In addition, in conjunction with the miniaturization of the cassette body, it is necessary to construct it from a thin plate material.

Therefore, if the slide guard is made of a molded plastic material or a thin metal material, the slide guard provided in this manner may be subject to plastic deformation due to aging, molding distortion, deformation due to mechanical external pressure, or the cassette. There is a problem in that the cassette can easily come off from the cassette body due to an impact such as a fall applied to the cassette body.

(Purpose of the invention) The present invention was made to solve the above problems, and is an easy-to-assemble audio device that has a slide guard that has a structure that prevents it from falling off and has an excellent dustproof effect when sliding. The object of the present invention is to provide a magnetic tape cassette.

(Structure of the invention) That is, the above-mentioned object of the invention is to include a pair of hubs around which magnetic tape is wound, an opening for allowing the magnetic tape to be pulled out in front of the cassette, and a hub on the front side of the opening. In the magnetic tape cassette, the slide guard is arranged along the outer surface of the lower half case, and the magnetic tape cassette is composed of an upper and lower half case including a guard panel that covers the lower half case, a slide guard that covers the lower side, and a locking member and friction sheet that lock the hub. The cassette can be slid in the front and back direction, and has side pieces that rise along the cassette side walls on both left and right sides and whose upper portions are bent toward the inside of the case. A magnetic tape cassette comprising an engaging part for preventing the slide guard from coming off and for dustproofing, which rises and extends from the inwardly bent end of the piece along the side piece with a length substantially equal to that of the side piece. This is achieved by

Hereinafter, the present invention will be described in detail based on embodiments illustrated in the drawings.

The magnetic tape cassette 1 shown in FIG.
It is about the same size or smaller than the compact cassette used for audio equipment. The magnetic tape cassette 1 includes a pair of flangeless type hubs 4 in which a magnetic tape T is wound inside a cassette case consisting of upper and lower half cases 2 and 3, and a friction case 5 for smoothing the rotation of the hubs 4. and a locking member 6 for preventing unexpected rotation of the hub 4, a guard panel 8 that closes the front side of the opening 10 at the front of the cassette case, and a slide that closes the lower side of the opening 10. A guard 20 is attached.

The slide guard 20 has a thin plate shape, and its left and right end portions are formed into side pieces 26 that rise at right angles along the side wall 15 of the lower half case 3, and its vertical cross-sectional shape is approximately U-shaped. It is structured like this. Further, the tips of the both side pieces 26 are bent so as to fit into the cassette case. An engaging portion 27 is formed at the inner end of the bent cassette and extends along the side piece 26 with substantially the same length as the side piece 26. The engaging portions 27 engage with the inner surfaces of the left and right side walls of the upper half case 2 when the cassette is assembled. That is, the engaging portion 27 has a function of preventing the slide guard from coming off, and also has a sliding guide function of the slide guard, and also has a dust-proofing function of blocking a considerable range of the slit formed by the step portion 15a. It is something that you have. Furthermore, the tip 27a of the engaging portion 27
is formed in a tapered shape that is inclined toward the outside of the slide guard 20 (see FIG. 2).

Further, the slide guard 20 has a transparent hole 23 corresponding to the reel shaft insertion hole 14 on a surface corresponding to the bottom of the lower half case 3, and a slide guard that urges the slide guard 20 forward of the cassette. An engagement protrusion 22 is formed with which the spring 25 is engaged and which is received in a notch 18 formed in the guard panel 8, which will be described later.

Hereinafter, each of the other constituent elements will be explained in order.

In FIG. 1, each of the hubs 4 is formed with an outer peripheral edge 4a that protrudes concentrically with the tape winding surface so that the engaging portion 7 of the locking portion 6 can engage with the hub.

The guard panel 8 has a U-shaped horizontal cross section as in the case of a conventional video cassette, and has rotating support shafts 9 protruding from both left and right end pieces facing each other. The guard panel 8 is provided with a hole 16 formed when the upper and lower half cases 2 and 3 are stacked together, or a hole (not shown) formed in one of the upper and lower half cases 2 and 3. It is attached so that the support shaft 9 is rotatably inserted and fitted. Further, the guard panel 8 is urged in a direction to close the opening 10 by a guard panel spring 28.

A notch 18 is formed in the center of the lower edge of the front wall 17 of the guard panel 8, and is configured to prevent the cassette from being inserted in the front-rear direction incorrectly when loading the magnetic tape cassette 1 into a recording/reproducing apparatus. has been done. That is, the protrusion for preventing incorrect insertion provided on the bucket, which is the cassette receiving part of the cassette insertion part of the recording and reproducing apparatus, corresponds to the notch 18, so that the magnetic tape cassette 1 can be inserted normally in the front and rear directions. It is designed so that it can be loaded into a recording/reproducing device only when the

In the lower half case 3, the hub 4 is provided with a pair of corresponding reel shaft insertion holes 14, as in a conventional video tape cassette, and the opening is formed so that the magnetic tape T can be pulled out in front of the cassette. A tape outlet 11 is formed at both left and right ends of the tape 10. or,
The bottom of the cassette between the tape drawer openings 11 is
The side wall thereof is formed to recede to the rear of the cassette, and when the magnetic tape cassette 1 is loaded into a recording/reproducing apparatus, the tape pull-out member of the recording/reproducing apparatus can enter into the cassette from below. ing.

At the upper edge of the side wall 15 of the lower half case 3,
A stepped portion 15a is formed to form a slit along the front-rear direction of the cassette when the upper and lower half-cases 2 and 3 are stacked on top of each other to assemble the cassette.

The front portion of the upper half case 2 is constructed so as to form the tape outlet 11 together with the lower half case 3 when combined with the lower half case 3, similar to a conventional video tape cassette. Further, although not shown in the drawings, means for regulating the rotational position of the hub 4 is provided on the inner surface of the upper half case 2.

When assembling the magnetic tape cassette 1,
First, the slide guard 20 is inserted into the lower side of the lower half case 3 from the front of the lower half case 3, and the lower surface of the engaging part 27 is attached to the step on the upper edge of the side wall 15 of the lower half case 3. Fit it so as to engage with the portion 15a.

Further, in the slide guard 20, one end of the slide guard spring 25 is fitted onto the locking pin 13 formed on the lower half case 3, and the other end is engaged with the engagement protrusion 22. This urges the cassette forward and allows the cassette to slide forward and backward.

Thereafter, the hub 4 with the magnetic tape T wound thereon is placed on the friction sheet 5 laid on the inner surface of the lower half case 3, so as to correspond to the reel shaft insertion hole 14, and the magnetic tape The T is mounted between the left and right tape guides 12 in such a way that it comes out of the cassette from the tape draw-out port 11. A friction sheet 5 is further placed on top of the friction sheet 5, and the locking member 6 is disposed on top of the friction sheet 5. The locking member 6 is biased toward the rear of the cassette by a biasing means (not shown) so that the cassette can slide in the front-rear direction. Incorporated.

The guard panel 8 is attached to the upper half case 2.
When the guard panel is covered, the rotary support shaft 9 is rotatably inserted into the hole 16 and is attached so as to be biased in the closing direction by the guard panel spring 28.

Finally, the upper half case 2 is overlapped with the lower half case 3 so as to fit into the lower half case 3. At this time, since the tip 27a of the engaging portion 27 of the slide guard 20 that is overlapped is formed in a tapered shape, the upper half case 2 can be inserted into the upper half case 2 to improve the ease of assembling the upper and lower half cases 2 and 3. are doing.

In this way, the magnetic tape cassette 1 is constructed by stacking the upper and lower half cases 2 and 3 on top of each other.
It is assembled by fastening with screws etc.

Note that the upper half case 2 is provided with a stopper portion (not shown) for preventing the slide guard 20 from jumping out forward, and by overlapping the upper and lower half cases 2 and 3, the slide Guard 20 is held in a cassette.

When the magnetic tape cassette 1 is stored, the guard panel 8 and the slide guard 20 close the opening 10, and the outer peripheral edge 4a of each of the hubs 4 and the engaging portion 7 of the lock member 6 close. are in contact with each other to prevent the hub 4 from rotating.

The materials of the upper and lower half cases 2, 3, the guard panel 8, and the lock member 6 may be conventionally used plastic resins such as polyacetal resin, ABS resin, and PS resin. Constructed from plastic resin. Note that the slide guard 20 is
For example, the cassette body may be made of metal such as stainless steel, but since the cassette body is made of plastic resin, the cassette body will be scraped by repeated sliding operations of the slide guard, so preferably the upper and lower half cases 2,
The same quality as 3 is desirable.

The magnetic tape T may be a ferromagnetic iron oxide or chromium dioxide tape, but preferably one suitable for high-density recording and reproduction, such as a metal tape or a vapor-deposited tape.

The operation of each member when the magnetic tape cassette 1 constructed as described above is loaded into a recording/reproducing apparatus will be described below.

When the magnetic tape cassette 1 is loaded into a cassette insertion section of a recording/reproducing apparatus, the opening 1
It is pushed in with the 0 side facing forward (in the direction of arrow A shown in Figure 3). During this push-in operation, the slide guard 20 allows the engagement protrusion 22 to come into contact with, for example, a protrusion for preventing incorrect insertion in the cassette insertion section, so that the slide guard 20 moves the outside of the rising wall surface of the engagement section 27 upward. The cassette slides rearward (in the direction of arrow B) while slidingly contacting the inner surface of the side wall of the half case 2 to open the lower side of the opening 10 and open the through hole 2.
3 are aligned with the reel shaft insertion hole 14, so that a reel shaft for driving the hub can be inserted.

Thereafter, the magnetic tape cassette 1 moves in a direction perpendicular to the pushing direction, that is, downward (in the direction of arrow C). During this downward movement, the guard panel 8 uses the pivot shaft 9 as a fulcrum, for example, by having its lower edge abutted by a guard panel opening means provided deep within the cassette insertion section. The cassette case is opened upward (in the direction of arrow D).

Further, when the guard panel 8 is opened, the left and right ends of the guard panel 8 catch the tips of the left and right projecting pieces 19 of the lock member 6, and slide the lock member 6 toward the front of the cassette. let Therefore, the engagement between the hub 4 and the locking member 6 is released, and the hub 4 becomes rotatable.

In this way, loading of the magnetic tape cassette 1 is completed by the pushing operation and downward movement, and the opening 10 is completely opened by sliding the slide guard 20 and opening the guard panel 8. The contact between the outer peripheral edge 4a and the engaging portion 7 is released, and as a result, the magnetic tape T can be pulled out from the opening 10 toward the front of the cassette, and the hub 4 can rotate. , recording and reproducing using a rotating head system becomes possible.

When the magnetic tape cassette 1 is taken out from the recording/reproducing apparatus, it moves with a stroke opposite to that when it was loaded, and first, the guard panel 8 is released from contact with the guard panel opening means, and the guard panel 8 is released from the guard panel opening mechanism. Due to the biasing force of the panel spring 28, the opening 1
Close the front side of 0. As the magnetic tape cassette 1 continues to be pulled out, the slide guard 20 is released from contact with the erroneous insertion prevention protrusion, so that the slide guard spring 25 is released.
The cassette is slid forward by the urging force of , and the opening 10 is completely closed.

Further, by rotating the guard panel 8 so as to close the opening 10, the engagement between the left and right end pieces of the guard panel 8 and the tip of the projecting piece 19 is released. As a result, the locking member 6 is slid toward the rear of the cassette by a biasing means (not shown), and the engaging portions 7 abut against the outer peripheral edge 4a, thereby locking the hub 4 so that it does not rotate. do. Furthermore, as the slide guard 20 slides to close the opening 10, the positions of the reel shaft insertion hole 14 and the hole 23 are shifted, and the reel shaft insertion hole 14 is closed.

(Effects of the Invention) As described above, when the magnetic tape cassette 1 of the present invention is stored, the guard panel 8 and the slide guard 20 completely close the opening 10, and the slide guard 20 completely closes the opening 10. Since the reel shaft insertion hole 14 is also closed, the protective effect and dustproof effect for the magnetic tape T mounted in the opening 10 are extremely excellent. Further, the slide guard 20 is provided so that the outer side of the rising wall surface of the engaging portion 27 is always in sliding contact with the inner surface of the side wall of the upper half case 2, so that the engaging portion 27 does not fall out of the slit. At the same time, it is possible to prevent dust from entering the slit between at least the slide guard 20 and the side wall end surface of the upper half case 2, thereby preventing deterioration of recording and reproducing characteristics.

Further, as in the embodiment described above, the tip of the engaging portion 27 of the slide guard 20 is formed into a tapered shape to facilitate insertion of the upper half case 2, thereby improving the ease of assembling the magnetic tape cassette 1. I'm doing well.

Although it was mentioned earlier that the present invention is applicable to magnetic tape cassettes that are the same size or smaller than conventional audio compact cassettes (Philips type), it is not necessarily limited to this, and can be applied to conventional video tape cassettes. cassette or other types of magnetic tape cassettes.

[Brief explanation of drawings]

Fig. 1 is an exploded perspective view showing one embodiment of the present invention, Fig. 2 is a sectional view of essential parts of the magnetic tape cassette shown in Fig. 1, and Fig. 3 is an assembled state of the magnetic tape cassette shown in Fig. 1. FIG. 1... Magnetic tape cassette, 2... Upper half case, 3... Lower half case, 4... Hub, 4a
...Outer peripheral edge, 5... Friction seat, 6...
... Lock member, 7 ... Engagement part, 8 ... Guard panel, 9 ... Rotation shaft, 10 ... Opening, 11 ...
Tape drawer opening, 12...Tape guide, 13
... Locking pin, 14 ... Reel shaft insertion hole,
15... Side wall, 15a... Step, 16... Hole, 1
7... Front wall, 18... Notch, 19... Overhanging piece, 20... Slide guard, 22... Engaging protrusion, 23... Transparent hole, 25... Spring for slide guard, 26... Side piece, 27... Engaging portion, 27a...
...Tip.

Claims (1)

[Claims for Utility Model Registration] 1. A guard that houses a pair of hubs 4 wrapped with magnetic tape, has an opening 10 that allows the magnetic tape to be pulled out to the front of the cassette, and covers the front side of the opening. In a magnetic tape cassette consisting of upper and lower half cases 2 and 3, each of which includes a slide guard 20 that covers a panel 8 and the lower side, a locking member 6 that locks the hub, and a friction sheet 5, the slide guard covers the lower half of the magnetic tape cassette. The cassette can be slid forward and backward along the outer surface of the case, and has side pieces 26 on both left and right sides that rise along the side walls of the cassette and whose upper portions are bent toward the inside of the case, so that the vertical cross section is approximately U-shaped. The slide guard has an engaging portion 27 for preventing the slide guard from slipping off and for dustproofing, which extends from the inwardly bent end of the side piece and extends along the side piece with approximately the same length as the side piece. A magnetic tape cassette made of 2. The magnetic tape cassette according to claim 1, wherein the distal end of the engaging portion is formed into a tapered surface that is inclined toward the outside of the slide guard.