JPH0341348Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a magnetic tape cassette, and more particularly to a novel compact cassette for audio use of a size comparable to or smaller than the Philips type.

(Prior art) In recent years, cassette tape recorders have become smaller and lighter, and the magnetic tape cassettes used in them have also become smaller. It's starting to be desired. Digital methods such as pulse code modulation (PCM), which record and playback by converting input signals into pulses, are known to meet these demands. Video tape cassettes have become widely popular because of the need to widen the recording frequency band to about twice that of conventional audio tapes.

Except for special cases, these video tape cassettes use a rotating head system, which protects the magnetic tape and records and plays high-density wide-frequency bands.
In order to prevent the influence of dust on the recording and reproducing characteristics, a guard panel is provided that rotates to open and close the tape draw-out opening provided on the front side of the cassette.

The magnetic tape cassette that is the subject of this invention is a magnetic tape cassette for digital audio that employs a relatively wide frequency band recording and reproducing method, similar to the video tape cassette, and has a performance comparable to that of conventional compact cassettes for audio. It is extremely small, smaller in size. Furthermore, it is expected that magnetic tape cassettes for digital audio will be used more frequently outdoors, similar to conventional audio cassettes, and that they will often be carried and used without storage cases.

Under these circumstances, various magnetic tape cassettes for digital audio have been proposed. This magnetic tape cassette has a guard panel that rotates to open and close the tape drawer opening provided on the front side of the cassette like the video tape cassette described above, as well as a guard panel that slides back and forth along the outer surface of the bottom of the cassette. A slide guard is provided to close the lower side of the opening in front of the cassette.

However, the magnetic tape cassette for digital audio is smaller and lighter than the video tape cassette, and is also equipped with various members such as the slide guard and a lock member that stops the hub from rotating, and which operates these members. Since a biasing means such as a spring is incorporated to cause the cassette to move, the structure of the cassette becomes relatively complicated, and there is a problem in assembling the cassette.

(Purpose of the invention) The present invention has been made in view of the above problems, and its purpose is to provide a magnetic tape cassette that is easy to assemble and is configured so that the slide guard and lock member can operate reliably. It is something to do.

(Structure of the invention) The purpose of the invention is to
3, a pair of hubs 4 around which a magnetic tape T is wound;
, a friction sheet 5 and a locking member 6 for locking the hub 4, and a pair of tape guides 12 on the front side of the cassette of the lower half case 3
It has an opening 10 in front and below the magnetic tape T mounted between the tape guides 12 to allow the magnetic tape T to be pulled out to the front of the cassette, and the front side of the opening 10 is closed. The rotatable guard panel 8 is slidable in the front and back direction of the cassette, and the moving end on the front side of the cassette closes the lower side of the opening 10 and the reel shaft insertion hole 14 of the lower half case 3, and the rear side A transparent hole 23 communicating with the reel shaft insertion hole 14 at the moving end of the
In the magnetic tape cassette 1 comprising a slide guard 20 having The slide guard 20 is provided with a locking portion 7 extending to the rear of the cassette to stop the rotation of the cassette, and projecting pieces 19 extending to the front of the cassette and capable of being locked by the guard panel 8 at both ends of the cassette in the left-right direction, and the slide guard 20 is formed in a plate shape. A projecting portion 27 that projects inward from the side piece 26 that rises upward from the left and right ends of the cassette is connected to the side wall stepped portion 15 of the lower half case 3.
The cassette can be slid back and forth along the outer surface of the bottom of the lower half case 3 while being guided by the fulcrum part 31 on the boss 13 provided near the opening 10 of the lower half case 3. One arm 32 extending from the fulcrum 31 urges the locking member 6 toward the rear of the cassette, and the other arm 33 engages the engagement protrusion 22 of the slide guard 20 protruding into the opening 10. This is achieved by a magnetic tape cassette characterized in that it is provided with an integral spring 30 that engages with the slide guard 20 to bias the slide guard 20 forwardly.

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

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

Note that each of the hubs 4 is provided with the lock member 6.
An annular portion 4a is formed that protrudes concentrically with the tape winding surface so that it can be engaged with the tape winding surface.

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

Notches 18 are formed on the left and right sides of the lower edge of the front wall 17 of the guard panel 8, respectively, to prevent the cassette from being inserted in the front-back direction incorrectly when loading the magnetic tape cassette 1 into a recording/reproducing apparatus. It is configured. 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 is located in the notch 18.
By being compatible with this, the magnetic tape cassette 1 can be loaded into the recording/reproducing apparatus only when the magnetic tape cassette 1 is inserted correctly in the front and rear directions.

The lower half case 3 is provided with a pair of reel shaft insertion holes 14 through which the hub 4 corresponds, similar to a conventional video tape cassette, and the opening is opened 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 portion 10. Furthermore, a boss 13 having a slit 13a at its upper end is protruded near the tape outlet 11 (on the right side in the figure). The boss 13 is a portion to which an integral spring 30 is attached which urges the lock member 6 and the slide guard 20 in a desired direction.
Further, the bottom between the tape guides 12 near the tape outlet 11 of the lower half case 3 is cut out, and as shown in FIG. 4, the front side wall surface 45 of the lower half case 3 is curved from the left and right ends. The center part is retracted towards the rear of the cassette. The magnetic tape cassette 1 is constructed so that when it is loaded into a recording/reproducing apparatus, the tape pull-out member of the apparatus can enter into the cassette from below.

The integral spring 30 protrudes from a fulcrum portion 31 around which two arms, an upper arm 32 and a lower arm 33, are wound into a coil. The coiled portion of the fulcrum portion 31 is divided into an upper and a lower portion. The upper arm 32 extends from the upper coil part.
is formed in a shape such as a U-shape in the thickness direction of the cassette so that the tip thereof can be caught so as to urge the locking member 6 toward the rear of the cassette. The lower arm 33 engages with the engaging protrusion 22 provided on the slide guard 20 to urge the slide guard 20 forward of the cassette.

Further, a stepped portion 15a is formed on the upper edge of the side wall 15 of the lower half case 3 so as to form a slit through which the projecting portion 27 of the slide guard 20 can enter into the cassette when the cassette is assembled. has been done.

The slide guard 20 is plate-shaped, and has a transparent hole 23 corresponding to the reel shaft insertion hole 14 on a wall surface corresponding to the bottom surface of the cassette, the engaging protrusion 22, and a notch 1 in the guard panel 8.
A side piece 2 is formed with a protrusion 21 to be received in the cassette side wall 15, and has both left and right ends rising along the cassette side wall 15.
6, and each of the upper edges of the side pieces 26 is provided with the above-mentioned projecting portions 27 that project so as to slightly enter into the cassette case.

The front portion of the upper half case 2 is configured so that, when combined with the lower half case 3, the upper half case 2 forms the tape outlet 11 together 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 attached to the outer surface of the bottom of the lower half case.
Attach it so that it enters the cassette starting from 5a. 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. Furthermore, another friction sheet 5 is placed over it, and the locking member 6 is placed over the friction sheet 5.

Thereafter, the fulcrum portion 31 of the integral spring 30 is fitted into the boss 13, and the distal end portion of the upper arm 32 is engaged with the lock member 6, and the distal end portion of the lower arm 33 is engaged with the locking member 6. Projection 2
2. Furthermore, when the upper half case 2 is placed on the guard panel 8, the rotation support shaft 9 is rotatably inserted into the hole 16, and the guard panel spring 28 is also attached, so that the guard panel 8 is closed. It is attached so that it is biased in the direction.

In this way, the magnetic tape cassette 1 is assembled by overlapping the upper and lower half cases 2 and 3 and then fastening them with screws or the like.

When the magnetic tape cassette 1 is stored, the opening 10 is closed by the guard panel 8 and the slide guard 20, and the annular portion 4a of each hub 4 and the locking member 6 are not engaged with each other. The joint portion 7 is in contact with the hub 4, thereby preventing unexpected rotation of the hub 4.

The materials of the upper and lower half cases 2, 3, the guard panel 8, and the locking member 6 may be conventionally used plastic resins such as polyacetal resin, ABS resin, and PS resin. It is preferable to use a material similar to plastic resin because it can be manufactured at low cost, but it may also be made of metal such as stainless steel.

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 FIG. 2). During this push-in operation, the slide guard 20 slides toward the rear of the cassette (in the direction of arrow B) when the protrusion 21 comes into contact with, for example, a protrusion for preventing incorrect insertion in the cassette insertion portion, and the slide guard 20 slides toward the bottom of the opening 10. Along with opening the side,
Each of the transparent holes 23 corresponds to the reel shaft insertion hole 14, so that a reel shaft for driving the hub can be inserted therein.

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 is opened upwards (in the direction of arrow D) about the rotary shaft 9 as a fulcrum when a guard panel opening means provided deep inside the cassette insertion section comes into contact with its lower edge. Ru.

Further, when the guard panel 8 is opened, both left and right end pieces of the guard panel 8 are attached to the lock member 6.
Hook the tips of the left and right projecting pieces 19 and slide the lock member 6 toward the front of the cassette. Therefore, the hub 4 is released from the locking portion 7 of the locking member 6 and 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. 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 be rotated, making it possible to perform recording and reproducing using a rotating head system.

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 protrusion for preventing incorrect insertion, and the lower arm 3 of the integral spring 30 is released.
The cassette is slid forward with a biasing force of 3, and the opening 10 is completely closed.

Furthermore, as the guard panel 8 rotates to close the opening 10, the engagement between the left and right end pieces of the guard panel 8 and the tip of the overhang piece 19 is released. As a result, the integral spring 3
Due to the biasing force of the upper arm 32, the locking member 6 is slid toward the rear of the cassette, and the locking portions 7 abut against the annular portion 4a, thereby locking the hub 4 so that it does not rotate. Furthermore, since the slide guard 20 slid to close the lower side of the opening 10, the transparent hole 2
3 and the reel shaft insertion hole 14 are shifted, and the reel shaft insertion hole 14 is closed.

The integral spring 30 is connected to the slit 1 of the boss 13.
Since the center portion of the fulcrum portion 33 is fitted into the support portion 3a, the biasing forces of the upper arm 32 and the lower arm 33 do not influence each other, and both biasing forces can be set appropriately. and stabilize it.

In the embodiment, the integral spring 30 is
Although the fulcrum portion 31 is formed into a coil shape divided into two upper and lower parts, the present invention is not limited to this form; for example, the integral spring 30
Alternatively, the shape of the fulcrum portion 31 may be simply one coil, and the fulcrum portion 31 may be attached to the boss 13 so as to be inserted thereinto.

Furthermore, the integral spring 30 in the present invention
can also be changed as shown in FIG. 3, for example.

In FIG. 3, the integral spring 40 has a fulcrum portion 41 located at a boss 1 formed in the lower half case 3.
3, and is simply bent so that the tip of the upper arm 42 engages with the lock member 6 and the lower arm 43 engages with the engagement protrusion 22 of the slide guard 20. The fulcrum portion 41 is not configured in a coil shape.

Further, in the embodiment described above, the sliding of the slide guard 20 to the rear of the cassette was performed by the projections for preventing incorrect insertion coming into contact with the projections 21 formed on the left and right sides of the front edge of the slide guard. is not necessarily limited to such a configuration; for example, the engaging protrusion 22 that engages with the lower arm 33 of the integral spring 30 is provided at the front edge of the slide guard, and the engaging protrusion 22 that engages with the lower arm 33 of the integral spring 30 is also provided on the guard panel 8. It is also possible to provide a notch for receiving the engagement protrusion 22.

(Effects of the invention) As described above, the magnetic tape cassette 1 of the invention has the opening 10 of the lower half case 3.
An integral spring 3 locked to a boss 13 provided near the
One arm 32 of the spring 30 urges the locking member 6 toward the rear of the cassette, and the other arm 33 of the integral spring 30 biases the slide guard 20 toward the front of the cassette. The member 6 and the slide guard 20 can be operated reliably.

Further, according to the present invention, the means for urging the locking member 6 and the slide guard 20 to the hub locking position and the dustproof position, respectively, is the integral spring 30.
Since only one piece is required and the integral spring 30 is easy to assemble, the ease of assembling the cassette can be extremely improved.

Although it was stated at the beginning that the present invention is applicable to digital audio magnetic tape cassettes that are the same size or smaller than conventional audio compact cassettes, the present invention is not necessarily limited to this, and is applicable to video tape cassettes. It can also be applied to various other magnetic tape cassettes.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing one embodiment of the present invention, Fig. 2 is a perspective view showing the assembled state of the magnetic tape cassette shown in Fig. 1, and Fig. 3 is a modification of the embodiment shown in Fig. 1. FIG. 4 is a perspective view of the vicinity of the opening of the lower half case. 1... Magnetic tape cassette, 2... Upper half case, 3... Lower half case, 4... Hub, 4a
...Annular part, 5...Friction sheet, 6...
Lock member, 7... Locking part, 8... Guard panel, 9... Rotating shaft, 10... Opening, 11...
Tape drawer opening, 12...Tape guide, 13
... Boss, 13a ... Slit, 14 ... Reel shaft insertion hole, 15 ... Side wall, 15a ... Step, 16 ... Hole, 17 ... Front wall, 18 ... Notch, 19 ... Overhang piece , 20...Slide guard, 21...Protrusion, 22...Engagement protrusion, 23...
Transparent hole, 26... side piece, 27... overhanging part, 2
8... Guard panel spring, 30, 40... Integral spring, 31, 41... Fulcrum portion, 32, 42... Upper arm, 33, 43... Lower arm, 45... Front side wall surface.

Claims (1)

[Claims for Utility Model Registration] A pair of hubs 4 wrapped with magnetic tape T, a friction sheet 5, and a locking member 6 for locking the hubs 4 are built into the upper and lower half cases 2 and 3. A pair of tape guides 12 are provided on the front side of the cassette of the lower half case 3.
a rotatable guard for closing the front side of the opening 10, which has an opening 10 in front and below the magnetic tape T mounted between the cassette and the opening 10 to allow the magnetic tape T to be pulled out to the front of the cassette; The panel 8 is slidable in the longitudinal direction of the cassette, and the front moving end of the cassette closes the lower side of the opening 10 and the reel shaft insertion hole 14 of the lower half case 3, and the rear moving end closes the reel shaft insertion hole 14 of the lower half case 3. In the magnetic tape cassette 1 comprising a slide guard 20 having a transparent hole 23 communicating with the shaft insertion hole 14, the locking member 6 is slidable in the longitudinal direction of the cassette and is formed on the upper edge of the hub 4. The cassette is provided with a locking portion 7 extending toward the rear of the cassette that engages with the annular portion 4a to stop the rotation of both hubs 4, and has projecting pieces 19 extending toward the front of the cassette and capable of being locked by the guard panel 8 at both ends of the cassette in the left-right direction. The slide guard 20 is formed into a plate shape, and a projecting portion 27 that projects inward from the side piece 26 rising upward from the left and right ends of the cassette is connected to the side wall stepped portion 15 of the lower half case 3.
The cassette can be slid back and forth along the outer surface of the bottom of the lower half case 3 while being guided by the fulcrum part 31 on the boss 13 provided near the opening 10 of the lower half case 3. One arm 32 extending from the fulcrum 31 urges the locking member 6 toward the rear of the cassette, and the other arm 33 engages the engagement protrusion 22 of the slide guard 20 protruding into the opening 10. A magnetic tape cassette characterized in that an integral spring 30 is provided which engages with the slide guard 20 to urge the slide guard 20 forwardly.