JPH0621106Y2 - Magnetic tape cassette - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a magnetic tape cassette, and more particularly to a magnetic tape cassette having a structure in which a magnetic tape is pulled out to the front of the cassette for recording and reproduction.

[Prior Art] In recent years, high-density recording has been performed using a magnetic tape. A typical example of this is a magnetic tape cassette (video tape cassette) such as the VHS system or the β system.

This kind of magnetic tape cassette has different recording formats or some structural differences depending on its application such as consumer use, commercial use, etc., but the basic structure is that the magnetic tape is opened from the opening in front of the cassette. It is to be pulled out for recording and reproduction. That is, it has a rotatable guard panel that closes the opening when the cassette is stored (when not in use) and opens the opening when recording and reproducing. Further, the magnetic tape cassette loaded in the recording / reproducing apparatus (VTR) is first inserted in the horizontal direction, and then continuously moved in the cassette thickness direction (generally downward), so that the guard panel is opened. The structure is such that the tape pull-out member enters the back side (non-magnetic surface side) of the tape and the magnetic tape is pulled out appropriately.

The magnetic tape cassette (video tape cassette) has a β system or M format system used for business, and a β system or VH for consumer use.
There are various types corresponding to the S method, and in order to avoid the inconvenience of erroneously using them, for example, the correspondence between the guide groove provided on the outer surface of the cassette case and the insertion guide protrusion of the cassette holder of the VTR is shifted. Although it has been devised, in order to guarantee its reliable operation, the groove length and groove depth of the guide groove must be large to some extent,
In addition, since a structure that does not affect other cassette structures is preferable, in the conventional case, the structure is slightly displaced in the central region of the bottom surface of the cassette.

However, if the positions of the guide groove and the like are slightly shifted as in the above-described device, for example, when a magnetic tape cassette that is smaller than the cassette holder and is mistakenly recognized is inserted, the guide groove and the guide protrusion correspond to each other. In some cases, there was a possibility of trouble due to misidentification. In recent years, in particular, various researches and developments have been made in various fields in order to realize higher quality recording and reproduction than ever before, and as a part of that, new magnetic tape cassettes have been developed, and similar magnetic tape cassettes have been developed. It is expected that there will be many types. Therefore, if the shape of the newly developed magnetic tape cassette is similar to the conventional one,
The problem of misidentification as described above is highlighted as an even greater issue. In particular, magnetic tape cassettes with different cassette sizes and specifications should be loaded by VT.
If it is loaded in a VTR different from R, a problem will occur which causes not only cassette damage but also VTR failure.

[Object of the Invention] The present invention has been made in view of the above problems, and it is possible to reliably prevent the inconvenience caused by erroneous recognition of a magnetic tape cassette, and to provide a magnetic tape provided with means that does not restrict the cassette structure. The purpose is to provide a cassette.

[Construction of the Invention] An object of the present invention is to incorporate a pair of tape reels around which a magnetic tape is wound, and to open and close the opening for recording and reproducing by pulling the magnetic tape outside on the front surface of the cassette. In a magnetic tape cassette having a guard panel that operates, at least 3
Guide grooves corresponding to the insertion guide projections of the book along the front-rear direction of the cassette are provided on the same line on both ends with the notch provided on the lower edge of the front wall of the guard panel, and on the central portion of the bottom surface of the cassette, and The guide groove can be achieved by a magnetic tape cassette, which is formed at a position deviated from a rotation area of the tape reel.

Embodiments of the present invention illustrated in the drawings will be described below.

FIG. 1 is a perspective view of the magnetic tape cassette 1 according to the present embodiment as viewed from the back side.

The magnetic tape cassette 1 shown in the figure has a pair of tape reels 5 around which magnetic tapes are wound, and is rotatably housed in a cassette case composed of upper and lower half cases 2 and 3 respectively corresponding to the hub holes 4. Most of the structure is conventional V
It is constructed almost in the same manner as an HS system video tape cassette. However, the structure of the bottom surface of the cassette is different from the conventional one. That is, at least three guide grooves 10, 11, 12 are provided on the bottom surface of the cassette.

The guide grooves 10, 11 and 12 are respectively along the front-rear direction of the cassette, and for example, the wide guide groove 10 is provided at substantially the center in the left-right direction of the cassette so as to pass through the hole 16 for inserting the optical sensor as in the conventional case. Guide grooves 11 and 12 are provided at both ends of the cassette, that is, at corners of the cassette case. Also, in the center of the lower edge of the guard panel 7, a guide groove 10
Corresponding to the above, a notch 14 is formed on the same line along the cassette insertion direction so that the guide groove 10 and the notch 14 communicate with each other, and the notch formed at the left and right ends of the guard panel 15. 13 and 15 have guide grooves 11 as well as notch 14.
And the guide groove 12 to communicate with each other.

The guide grooves 10, 11 and 12 described above are positioned so as not to adversely affect other components of the magnetic tape cassette 1. That is, the guide groove 10 provided in the center is located at a position outside the rotation region of the flange (lower flange) of the left and right tape reels 5 even if the guide groove 10 is somewhat wide and the groove depth is deep.
The guide grooves 11 and 12 at the left and right ends are also out of the rotation area of the tape reel 5. Therefore, the guide grooves 10, 11, 12 can be configured to have a sufficient depth, for example, to sufficiently exert their action.

On the other hand, in the cassette holder (not shown) on the VTR side,
For example, rib-shaped guide protrusions are provided at positions corresponding to the above-mentioned guide grooves 10, 11 and 12.
Alternatively, at a position corresponding to one of the guide grooves 12,
An opening member for opening the guard panel 7 is provided.

Therefore, if the magnetic tape cassette 1 is inserted into the cassette holder of the VTR in the correct direction, the guide grooves 10, 11 and 12 and the guide protrusions of the cassette holder are aligned, and these are fitted to each other so that the magnetic tape cassette 1 Is allowed to be inserted into the cassette holder, and the cassette holder is continuously moved downward, whereby the guard panel 7 is opened, the tape drawer member is inserted into the mouth portion 6, and the tape reel 5 and the rotary shaft are engaged. The cassette is loaded normally.

However, a magnetic tape cassette different from the magnetic tape cassette 1 having, for example, one guide groove substantially similar to the above-mentioned guide groove 10 only at the center of the bottom surface of the cassette is erroneously recognized as the magnetic tape cassette 1 of the present embodiment. Then, when trying to insert into the VTR (when the mistakenly recognized magnetic tape cassette has the same or smaller external dimensions than the magnetic tape cassette 1), it is possible to insert it to some extent, but the guide protrusion prevents insertion of a certain amount or more. Be blocked. In such a state, if the eject mechanism of the VTR is operated, the magnetic tape cassette is ejected from the VTR, and the magnetic tape cassette is damaged due to erroneous insertion and the VTR is out of order. To be prevented.

The above-mentioned erroneous insertion prevention effect is not simply due to the fact that a plurality of guide grooves are provided to distinguish it from other magnetic tape cassettes, but at least three guide grooves 10, 11 and 12 are provided at the center and left and right of the cassette bottom surface. Because it is located at both ends. That is, as shown in FIG. 1, the distance L ₂ between the central guide groove 10 and the other guide grooves 11, 12 is about half the dimension L _{1 in} the cassette longitudinal direction, and the magnetic tape If the size L _{1 of the} cassette is different, the size L ₂ between the guide grooves is naturally different, and even if a similar guide groove is formed in a similar magnetic tape cassette, the size L _{1 in the} cassette longitudinal direction is simply different. The type of magnetic tape cassette can be specified very easily.

In the above embodiment, three guide grooves are provided as shown in FIG. 1, but the present invention is not limited to this embodiment, and other guide grooves than those shown in FIG. 1 may be provided. Of course, there is no problem.

[Effect of the Invention] As described above, the magnetic tape cassette according to the present invention is
Since there are at least three guide grooves corresponding to the insertion guide protrusions provided on the cassette holder of R along the front-rear direction of the cassette at the center of the cassette bottom and at both left and right ends, the guide grooves are provided. The type of the cassette is naturally specified by the difference in the dimension in the longitudinal direction of the cassette, and the trouble due to the incorrect insertion of the similar magnetic tape cassette into the VTR can be very effectively prevented. In particular, the guide groove according to the present invention has an extremely easy structure and is effective as a cassette misidentification preventing means for the future increase in types of magnetic tape cassettes. Further, according to the present invention, since the guide groove is formed at a position deviating from the rotation area of the tape reel, for example, the groove depth can be increased and the VTR can be extended.
Since the insertion guide protrusion on the side can be configured to be large, the effect of preventing erroneous insertion can be made more reliable.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a magnetic tape cassette according to the present invention. 1 ... Magnetic tape cassette, 2 ... Upper half case, 3 ... Lower half case, 4 ... Hub hole, 5 ... Tape reel, 6 ... Mouse part, 7 ... Guard panel, 8 ... Rotating shaft , 10,11,12 …… Guide groove, 13,14,15 …… notch, 16 …… hole.

Claims (1)

[Scope of utility model registration request] 1. A magnetic tape having a pair of tape reels around which a magnetic tape is wound, having an opening on the front surface of the cassette for recording / reproducing by pulling the magnetic tape outside and a guard panel for opening / closing the opening. In the cassette, guide grooves along the cassette front-rear direction corresponding to at least three insertion guide protrusions of the recording / reproducing apparatus are provided on the bottom surface of the cassette.
Notches respectively provided in the lower edge of the front wall of the guard panel,
Lined up on the same line at the center and both ends of the cassette bottom,
The magnetic tape cassette is characterized in that the guide groove is formed at a position deviated from a rotation area of the tape reel.