JPH0945041A - Tape cassette - Google Patents

Abstract

(57) [Abstract] [Problem] When a signal is recorded / reproduced without causing a transfer phenomenon,
Provide a tape cassette that does not cause dropouts or errors. SOLUTION: A locking recessed portion 3a recessed on the outer periphery of a hub 3 and a clamper 14 fitted in the locking recessed portion 3a.
In the tape cassette, in which the base end of the tape is wound around the hub 3 and the tape is wound around the hub 3, and the base end of the tape winding surface of the clamper 14 is locked. The end portion on the side is provided with a protruding curved surface portion 14a formed so as to project in the width direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base end portion of a tape between a locking recess formed in the outer periphery of a hub and a clamper fitted in the locking recess. A tape cassette formed by stopping the tape and winding the tape around the hub. More specifically, a transfer phenomenon does not occur on the tape wound around the hub, and a dropout or an error does not occur at the time of recording / reproducing a signal. Regarding tape cassettes.

[0002]

2. Description of the Related Art Conventionally, as a tape cassette, a space between a locking recess formed in the outer periphery of a hub and a clamper fitted in the locking recess. In addition, a tape is known in which the base end portion of the tape is locked and the tape is wound around the hub. In this tape cassette, as shown in FIG. 6 attached, a pair of hubs 3 and 3 around which a tape 2 is wound are housed in a cassette body case 1. Hereinafter, one of the pair of hubs 3 and 3 will be described, but the other is similarly formed. The tape 2 wound around the hub 3 is composed of a magnetic tape and a leader tape, an end portion of the magnetic tape is joined to one end portion of the leader tape, and the other end portion of the leader tape, that is, the leader tape. , The base end portion 2a of the tape 2
As shown in FIG. 7, is locked between a locking recess 3a recessed in the outer periphery of the hub 3 and a clamper 4 fitted therein.

In the above-mentioned tape cassette, there is a possibility that a step or a gap may occur between the hub 3 and the clamper 4. Also, a step is formed between the hub 3 and the clamper 4 due to so-called sink marks during molding. Then, a so-called transfer phenomenon occurs, which causes a linear transfer trace at a right angle to the longitudinal direction of the tape 2 on the surface of the tape 2 wound and laminated on the step or the gap, and recording / reproducing of a signal. When the above is performed, there is a possibility that a signal may be lost at the transfer mark portion, resulting in a dropout or an error. Various techniques for eliminating the above-mentioned steps and gaps have been studied, but the transfer phenomenon could not be avoided.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a tape cassette which does not cause a transfer phenomenon on a wound tape and does not cause a dropout or an error when recording / reproducing a signal.

[0005]

DISCLOSURE OF THE INVENTION The inventor has found that the base end portion of a tape is placed between a locking recess formed in the outer periphery of a hub and a clamper fitted in the locking recess. In a tape cassette formed by locking and winding the tape around the hub, a protruding curved surface portion is formed at the end of the clamp winding side of the tape winding surface of the clamper on which the tape base end is locked. It has been found that the above-mentioned object can be achieved.

The present invention has been made on the basis of the above findings, and the base of the tape is provided between the locking recess formed in the outer periphery of the hub and the clamper fitted in the locking recess. In a tape cassette in which an end portion is locked and the tape is wound around the hub, the clamper has at least an end portion on a side where the tape base end portion is locked on the tape winding surface. The above object is achieved by providing a tape cassette having a protruding curved surface portion formed so as to project in the width direction.

The tape according to claim 1, wherein the protruding curved surface portion has a semicircular cross section in the width direction of the clamper at the highest portion of the protruding curved surface portion. The above object has been achieved by providing a cassette.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the tape cassette of the present invention will be specifically described below with reference to the drawings. In this embodiment, the same members as those in the conventional tape cassette shown in FIGS. 6 and 7 are designated by the same reference numerals, and the description thereof will be omitted. 1 is a plan view of an essential part of an embodiment of a tape cassette of the present invention, FIG. 2 is an enlarged plan view of an essential part of the tape cassette of FIG. 1, and FIG. 3 is a sectional view of a clamper according to the tape cassette of FIG. FIG. 3 is a sectional view taken along line AA and a sectional view taken along line BB of FIG. 2. Note that the tape is omitted in FIGS. 1 to 5 for convenience.

The tape cassette of this embodiment has a locking recess 3a formed in the outer periphery of the hub 3 and the locking recess 3a.
The tape is wound around the hub 3 by locking the base end of the tape between the tape and the clamper 14 fitted in a, and these are the same as those of the above-mentioned conventional technique.
Thus, in the tape cassette according to the present embodiment, the clamper 14 has the protruding curved surface portion 14a formed on the winding surface of the tape base end portion so as to protrude in the width direction thereof.

The tape cassette of the present embodiment will be described in detail. When viewed from the side, the protruding curved surface portion 14a rises in a convex shape and reaches the highest portion as shown in FIG. It is smoothly connected to the winding surface. The cross section of the protruding curved surface portion 14a in the width direction of the clamper 14 at the highest portion has a semicircular shape as shown in FIG. 3 (a). The distance d from the end of the clamper 14 on the side that locks the base end of the tape to the highest part of the protruding curved surface portion 14a is 0.05 to 3 mm, more preferably 0.2 to 1.5 mm. 14 protruding surface from the tape winding surface other than the protruding curved surface portion 14a
The height h up to the highest point of is 0.005 to 0.2 mm, more preferably 0.005 to 0.050 mm. The shape of the clamper other than the protruding curved surface portion 14a is the same as the conventional one, and as shown in FIG. 3B, the cross section in the width direction has a rectangular shape.

The molding die of the clamper in the tape cassette having the above-mentioned structure may be a cutting die of a conventional molding die of the clamper, so that it is not necessary to newly prepare a special die. In the tape cassette having the above-described configuration, the tape is wound in a state in which the step and the gap between the hub 3 and the clamper 14 are absorbed by the protruding curved surface portion 14a, so that the tape between the hub 3 and the clamper 14 is wound. Tape transfer phenomenon due to steps and gaps does not occur.

As described above, the tape cassette of this embodiment is
It can be manufactured by cutting and using a conventional mold, and the tape can be wound and laminated without causing a transfer phenomenon due to a step.

The tape cassette of the present invention is not limited to the above-mentioned embodiment, and the specific shapes and dimensions of each member can be appropriately changed without departing from the spirit of the present invention. For example, the shape of the protruding curved surface portion 14a is
A cross section in the longitudinal direction of the clamper 14 may have a semicircular shape like a so-called semi-drum shape as shown by a dotted line in FIG. 4, or may have a shape like a broken line shown in FIG. Further, the cross-section of the clamper 14 in the width direction does not have to be a semicircular shape, and as shown in FIG. 5A, even if both ends of the cross-section of the clamper 14 in the width direction are curved, )
As shown in, the cross section of the clamper 14 in the width direction may be rectangular. Further, the protruding curved surface portion 14a may be provided on the other end portion of the tape winding surface of the clamper 14 adjacent to the hub, if necessary.

[0014]

As described above, according to the tape cassette of the present invention, the transfer phenomenon does not occur on the tape wound around the hub, and the dropout and the error at the time of recording / reproducing the signal can be avoided. it can.

[Brief description of drawings]

FIG. 1 is a main part plan view showing a tape cassette according to an embodiment of the present invention.

FIG. 2 is an enlarged plan view of an essential part of the tape cassette shown in FIG.

3A and 3B are cross-sectional views of a clamper according to the tape cassette of FIG. 1, where FIG. 3A is a cross-sectional view taken along the line AA of FIG. 2 and FIG. 3B is a cross-sectional view taken along the line BB of FIG.

FIG. 4 is an enlarged plan view of an essential part of a clamper according to another embodiment of the present invention, which is a view corresponding to FIG. 2 in the cassette tape of FIG.

5 is a cross-sectional view of a clamper according to another two embodiments of the present invention and is a view corresponding to FIG. 3 (a) in the tape cassette of FIG.

FIG. 6 is a perspective view showing a general tape cassette.

FIG. 7 is a perspective view showing a hub and a clamper of a general tape cassette.

[Explanation of symbols]

 1 tape cassette body case 2 tape 2a base end 3 hub 3a locking recess 14 clamper 14a protruding curved surface

Claims (2)

[Claims] 1. A base end portion of a tape is locked between a locking recess formed on the outer periphery of a hub and a clamper fitted in the locking recess, and the tape is fixed to the above-mentioned portion. In a tape cassette wound around a hub, the clamper has a protruding curved surface formed so as to protrude in the width direction at least at the end of the tape winding surface where the tape base end is locked. A tape cassette characterized by having a section. 2. The tape cassette according to claim 1, wherein the protruding curved surface portion has a semicircular cross section in the width direction of the clamper at the highest portion of the protruding curved surface portion.