JP2000298973A - Magnetic tape cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly prescribe the lower limit height for running of a magnetic tape. SOLUTION: In this magnetic tape cassette, a pair of take-up hubs 26 around which a magnetic tape 24 is wound are housed in a cassette case, which is formed by coupling an upper half 10 and a lower half 12 by capping, with sheets 34 and 36 having a throttled shape between these hubs and upper and lower halves 10 and 12, and a projecting shape approximately equal to the throttled shape is provided in a part of the bottom of the lower half 12 corresponding to the throttled shape of the sheet interposed between take-up hubs 25 and the lower half 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic tape cassette, and more particularly, to a magnetic tape cassette that defines a lower limit height at which a magnetic tape runs.

[0002]

2. Description of the Related Art As is well known, a magnetic tape cassette is
After fixing each end of the long magnetic tape, a pair of take-up hubs around which the magnetic tape is wound are exposed, and only a portion of the magnetic tape stretched between the two take-up hubs is exposed. (Upper half and lower half). The case (upper half) has a closed position for covering the magnetic tape stretched between the pair of winding hubs to protect the magnetic layer surface of the magnetic tape, and an open position for exposing the magnetic tape from the case. A front lid rotatably supported between the two is provided.

When a magnetic tape cassette is loaded into a recording / reproducing apparatus (deck), the front cover is turned to an open position by a mechanism in the apparatus in conjunction with the cassette, and the magnetic tape stretched between winding hubs. Is exposed from the case. Then, the take-up hub is rotated and the magnetic tape runs, and the magnetic head in the apparatus contacts the magnetic tape, records information on the magnetic tape, and reproduces information from the magnetic tape.

If the magnetic tape moves up and down during running of the magnetic tape, the magnetic tape does not properly contact the magnetic head, so that proper recording / reproducing is not performed, and there is a possibility that other troubles may occur. Therefore, it is important to suppress the vertical movement during the running of the magnetic tape, to improve the regulation accuracy of the running position of the magnetic tape, and to stabilize the running performance. Therefore, conventionally, various devices have been devised to adjust the running position of the magnetic tape.

FIG. 6 is a sectional view showing an example of a conventional magnetic tape cassette. As shown in FIG. 6, between the upper half 100 and the lower half 102, the magnetic tape 106 (represented by a broken line) wound around the winding hub 104 is housed.
4 and the lower half 102, a sheet 108, and between the winding hub 104 and the upper half 100, a sheet 110,
Each is arranged. Conventionally, each sheet 108, 11
0, the shaping portions (squeezed portions) 108a, 110a
Is provided, whereby the position of the winding hub 104 is regulated.

At this time, when the drive of the deck is a flat type, the shaping portion 10 of the sheet 108 on the lower half side is particularly used.
8a is a winding hub 104 around which the magnetic tape 106 is wound.
Will support the weight. However, conventionally, sheet 1
08 The bottom surface 102a of the lower half below the shaping portion 108a
Is not provided with a convex shape such as a rib for improving the cushioning property of the shaping portion 108a, but rather, on the bottom surface 102a of the lower half, there is provided a thinned portion (recessed portion) in order to increase the cushioning property. There were things.

[0007]

However, when the lower limit position of the winding hub is regulated only by the shaping portion of the sheet as in the prior art, the shaping height of the shaping portion is limited. If this is too high, the imprinted portion alone cannot support the tape weight. Even in such a case, the formed shape may be deformed due to a drop impact, vibration during transportation, or the like. At this time, on the lower half side, since the imprinted portion is faced, the imprinted portion may be completely crushed and the imprint height may become zero.

In this case, the take-up hub cannot be supported at all by the shaping portion of the sheet, and the lower portion of the take-up hub 104 comes into contact with the bottom surface 102a of the lower half 102, as shown in FIG. In this case, there is a problem that regulation of the running position of the magnetic tape becomes impossible at all. Further, at this time, there arises a problem that the winding hub and the lower half slide with each other around the reel shaft insertion hole provided in the lower half, thereby causing resin shaving.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and has as its object to provide a magnetic tape cassette capable of appropriately defining a lower limit height of a magnetic tape during traveling.

[0010]

In order to solve the above-mentioned problems, the present invention provides a cassette case formed by joining an upper half and a lower half in a lid-like manner, and a pair of magnetic tapes wound around a cassette case. A winding tape, a magnetic tape cassette containing a sheet having a shaped shape interposed between an upper half and a lower half, respectively, wherein the sheet is interposed between the winding hub and the lower half. It is an object of the present invention to provide a magnetic tape cassette characterized in that a convex shape having substantially the same shape as the shaped shape is provided on a bottom surface portion of the lower half corresponding to the shaped shape.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a magnetic tape cassette of the present invention will be described based on a preferred embodiment shown in the accompanying drawings.
This will be described in detail.

FIG. 1 is an exploded perspective view showing a schematic configuration of a magnetic tape cassette according to the present invention. The magnetic tape cassette is mainly composed of an upper half 10, a lower half 12, and a slider 14 mounted slidably in the front-rear direction on the lower outer side of the lower half 12 and the upper half 10, which are combined together in a lid-like shape to form a casing of the cassette. It is composed of

As will be described later, a magnetic tape wound around and wound around a pair of winding hubs is accommodated in a cassette case composed of an upper half 10 and a lower half 12. When the cassette is not used, the upper half 10 is provided with a brake member 16 for inhibiting the rotation of the take-up hub so that the take-up hub rotates and the magnetic tape does not loosen. The brake member 16 has two brake pieces 16a.
a engages with a gear provided on the winding hub. When the cassette is not used, the brake member 16
Is biased by a brake spring 18 using a torsion coil spring so that the braking piece 16a is engaged with the gear. Further, the upper half 10 is provided with a front lid 20 on the front surface of the upper half 10 to protect a portion of the magnetic tape stretched between the pair of winding hubs when the cassette is not used.

The lower half 12 has a rectangular bottom surface 12a.
In addition, when a cassette is used, there are provided reel shaft insertion holes 12b, 12b for inserting the reel shaft into the cassette case, and both right and left ends of the bottom surface 12a extend forward.
c and 12c. This reel shaft insertion hole 12b,
A step is provided around the periphery of the winding hub receiving portion 12b.
h and 12h. Also, the left and right overhang portions 12c,
12c is provided with cylindrical ribs 12d, 12d for guiding the magnetic tape. The space between the left and right overhanging portions 12c is a space into which a so-called tape loading device provided on the recording / reproducing device (deck) side into which the magnetic tape cassette is loaded enters. On the bottom surface 12a of the lower half 12, a wall-shaped member 12e in which two split-tube-shaped ribs are continuously provided in a C shape is erected, and a column-shaped rib 12f is provided at the front center thereof.
Is provided. Then, a V-shaped leaf spring 22 is inserted between the columnar rib 12f and the wall-shaped member 12e.

The slider 14 is mounted on the bottom surface 12 of the lower half 12.
a, and slides in the front-rear direction of the cassette, but when positioned forward, the space between the left and right overhanging portions 12c of the lower half 12 and the reel shaft insertion hole 12c.
b and 12b are closed by a bottom surface 14a of the slider 14 for dust prevention. When the slider 14 is located rearward, the right and left overhanging portions 12 of the lower half 12 are provided.
c and 12c, and release the slider 1
The two holes 14b, 14b provided on the bottom surface 14a of the lower half 4 are aligned with the reel shaft insertion holes 12b, 12b of the lower half 12. When the cassette is mounted on the deck, the slider 14 is automatically located rearward by the action of the device in the deck. When the cassette is not used, the slider 14 is located forward by the V-shaped leaf spring 22. . A wall-shaped rib 14c is provided in front of the slider 14 to receive the urging force of the V-shaped leaf spring 22.

A magnetic tape wound around a take-up hub is accommodated between the upper half 10 and the lower half 12 with a sheet having a shaping shape interposed therebetween. FIG. 2 is a perspective view showing the magnetic tape and the sheet wound around the take-up hub. As shown in FIG. 2, the magnetic tape 24 is wound around a pair of winding hubs 26, 26. The take-up hub 26 is provided with a gear 30 at an upper portion on the inner peripheral side, and the rotation of the take-up hub 26 is restricted by the engagement of the braking piece 16 a of the brake member 16 with the gear 30.

When the take-up hub 26 around which the magnetic tape 24 is wound is housed in a cassette, sheets 34,
36 are interposed. The sheets 34 and 36 are provided with holes 34a and 36a, respectively, as indicated by reference numeral 12 in the lower half 12 in FIG.
It is positioned by passing it through a rib indicated by g. Each of the sheets 34 and 36 has a substantially rectangular shaped shape 38 and 40 that is convex on the side of the two winding hubs 26 in the lateral direction of the cassette. Sheets 34 and 36
The winding resistance is reduced when the take-up hub 26 rotates, the rotation is smoothed, and the height is regulated by supporting the take-up hub 26 around which the magnetic tape 24 is wound by the shaping shapes 38 and 40. Plays a role.

FIG. 3 is a sectional view of the sheet 34 taken along the line III-III in FIG. As shown in FIG. 3, the sheet 34 is provided on both sides of the hole 34b with a substantially rectangular shaped shape 38 that is convex toward the winding hub 26 so as to define the position of the winding hub 26 from below. I have.

In FIG. 4, the upper half 10 and the lower half 12 are connected in a lid-like manner, and a take-up hub 26 around which a magnetic tape 24 is wound is accommodated between the upper half 10 and the lower half 12 with sheets 34, 36 interposed therebetween. This is shown in a sectional view. However, winding hub 2
6 is a side view, and the magnetic tape 24 is indicated by a broken line.
As shown in FIG. 4, the winding hub 26 around which the magnetic tape 24 is wound has sheets 34 and 36 arranged vertically, and the position is regulated by the shaping shapes 38 and 40.
In particular, the weight of the magnetic tape 24 is supported by the shaping shape 38 of the sheet 34 on the lower half 12 side.
Is defined.

Therefore, a convex shape 50 having substantially the same shape as the shaped shape 38 is provided on the bottom surface 12a of the lower half 12 so as to define the lower limit position of the magnetic tape 24 while maintaining the cushioning property of the shaped shape 38. . The convex shape 50 is provided on the bottom surface 12a of the lower half 12 over the entire position corresponding to the shaping shape 38 as shown in FIG. Further, in order to maintain the cushioning property of the shaping shape 38, the convex shape 5
The height is set so that the upper part of 0 does not touch the shaped shape 38.

FIG. 5 is an enlarged view of a circle V indicated by a broken line in FIG. As shown in FIG.
The convex shape 50 provided on the sheet a is the shaping shape 3 of the sheet 34.
8 has substantially the same shape. In addition, there is a gap between the convex shape 50 and the shaped shape 38 to maintain the cushioning property of the shaped shape 38. At the same time, even if the shaping shape 38 is crushed and the lower portion 26a of the winding hub 26 comes into contact with the convex shape 50, the contact here is via the sheet 34,
At this time, the lower portion 26b of the winding hub 26 is
Is set so that it does not directly contact the winding hub receiving portion 12h. Further, in the example shown here, as for the shaped shape, as shown in FIG. 3, two substantially rectangular shapes are provided on both sides of the hole 34b, respectively, but the shaped shape is not limited to this. Not something. For example, between the two shaping shapes 38, 38 in FIG. 3 (entire center), a convex shape (shaping shape) having the same height may be formed. Even in such a case, the lower half has this shaping shape. A convex shape corresponding to the shape is provided.
In addition to this, various shaping shapes are conceivable, and the shaping shape of the sheet can be variously selected. By providing the convex shape in the lower half, the same effect as in the present embodiment can be obtained.

By defining the lower limit position of the winding hub 26 in this manner, the lower limit of the running height of the magnetic tape 24 is defined. At the same time, the winding hub 26
And the lower half 12 are in direct contact with each other, so that resin shaving due to sliding of the resins does not occur. In addition, since the height of the shaped shape 38 is very small,
The height of the convex shape 50 is also very small, and the provision of the convex shape 50 does not affect the change in the resin flow due to the change in the thickness when the lower half 12 is formed.

The drive of the deck on which the magnetic tape cassette is loaded is not limited to the flat type as described above, but also to the vertical type.
Similarly to the case where the convex shape 50 corresponding to the shaped shape 38 is provided on the bottom surface 12a of the lower half 12 with respect to the shaped shape 38 of FIG. , May also be provided on the corresponding bottom surface of the upper half 10. In this way, the position of the take-up hub can be properly regulated even in the case of a vertical drive.

As described above, according to the present embodiment, it is possible to appropriately define the lower limit position of the running of the magnetic tape while maintaining the cushioning properties of the seat. Although the magnetic tape cassette of the present invention has been described in detail above, the present invention is not limited to the above examples, and various improvements and changes may be made without departing from the gist of the present invention. Of course.

[0025]

As described above, according to the present invention, the lower half is provided with a convex shape having substantially the same shape as the shape of the sheet,
As a result, the position of the winding hub is regulated.
It has become possible to appropriately define the lower limit height when the magnetic tape runs.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a schematic configuration of a magnetic tape cassette according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a sheet housed inside the magnetic tape cassette of FIG. 1 and interposed between a magnetic tape wound around a take-up hub.

FIG. 3 is a cross-sectional view of the sheet taken along line III-III in FIG. 2;

FIG. 4 is a cross-sectional view showing a state in which a take-up hub around which a magnetic tape is wound is accommodated between upper and lower halves joined in a lid-to-lid manner via upper and lower sheets.

FIG. 5 is an enlarged view showing a portion indicated by a dashed circle V in FIG. 4 in an enlarged manner.

FIG. 6 is a sectional view showing a conventional magnetic tape cassette.

FIG. 7 shows a problem of the conventional magnetic tape cassette.
It is sectional drawing similar to.

[Explanation of symbols]

 Reference Signs List 10 Upper half 12 Lower half 12a Bottom of lower half 12b Reel shaft insertion hole 12c Overhang 12d Rib (for tape guide) 12e Wall-like rib 12f Columnar rib 12g Rib (for sheet positioning) 12h Take-up hub receiver Part 14 Slider 14a Slider bottom surface 14b Hole 14c Wall-shaped rib 16 Brake member 16a Brake piece 18 Brake spring 20 Front cover 22 V-shaped leaf spring 24 Magnetic tape 26 Take-up hub 30 Gear 34, 36 Sheet 38, 40 Shape part 50 convex shape

Claims (1)

[Claims] 1. A pair of winding hubs each having a magnetic tape wound thereon are provided in a cassette case formed by connecting an upper half and a lower half in a lid-like manner. A magnetic tape cassette interposed between the lower half and the accommodated magnetic tape cassette, the bottom half of the lower half corresponding to the shaping shape of the sheet interposed between the winding hub and the lower half; A magnetic tape cassette provided with a convex shape having substantially the same shape as the shaping shape.