JPH0448481A - Cassette half - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a cassette knife for storing magnetic tapes.

BACKGROUND OF THE INVENTION There are two methods for storing magnetic tapes: storing them in an open reel and storing them in a cassette half. A major advantage of storing in a cassette half is that it is easy to operate, and currently most consumer products use a cassette half.

On the other hand, 8! Recording technology has become more dense, and cassette halves have become smaller. - For example, the 8mm format has been significantly downsized compared to the bidet known for the VH3 and β formants. As a trend in magnetic recording technology, advances have been made in the ability to store large amounts of information in compact cassettes through narrower tracks, higher density, and thinner tapes.

Hereinafter, a conventional cassette will be explained with reference to the drawings.

FIG. 3 is a top view showing the structure of a conventional cassette half, in which 1 is an unwinding reel, 2 is a take-up reel, 3 is a half body, 4 is a magnetic tape, 6 is a lid, and 6 is a post.

When storing magnetic tapes, the lid portion 6 is generally closed in order to prevent dust and the like and improve storage performance. Some formants with low recording density do not have this lid structure. However, with the advancement of high-density recording, the lid structure has become more and more thorough. Furthermore, in new formats, the unwinding reel 1 and the take-up reel 2 are usually locked to prevent rotation when the tape is stored, in order to prevent problems caused by disturbances in the magnetic tape.

When using a magnetic tape, the lid portion 5 is opened so that the magnetic tape 4 can come into contact with the magnetic head on the cassette deck main body side. In some formats, the magnetic tape drawer post on the cassette deck side moves to perform loading, while in other formats the post does not move and the magnetic head comes into direct contact with it. In any case, a post 6 is provided to place the magnetic tape 4 in a position where it can come into contact with the magnetic head.

Problems to be Solved by the Invention In such a conventional cassette half, when the magnetic tape 4 is stored and stored in the cassette half, a major problem is shape transfer. Traditionally, this has been a problem,
This involves transferring the shapes of the unwinding reel 1 and the take-up reel 2, and when a reel hub is used, serious problems arise such as the shape of the step between the reel harp and the reel. but,
All of these problems can be improved considerably by giving sufficient consideration. Another part where shape transfer is a problem is the post 6 part. For conventional magnetic tape, for example, the VHS format has a thickness of 16 to 19 μm.
Since the magnetic tape had a thickness of about 100 yen, shape transfer by the post 6 hardly occurred.

However, in the 8 mm format, the magnetic tape thickness is 10 mm.
．． It becomes about 6 to 13 pm, and shape transfer becomes a problem depending on the storage environment. The shape transfer referred to here is slightly different from the shape transfer that occurs in the reel section, in which the magnetic tape 4 winds around the post 6 and has a curl, and only that part curls strongly in the longitudinal direction of the tape depending on the post diameter. This is a phenomenon that occurs. When the shape transfer by this post 6 occurs,
The portion where the shape transfer has occurred can no longer make stable contact with the head, resulting in momentary vertical synchronization failure in the case of a video tape recorder. In the future, in order to miniaturize and increase the density of cassette halves, it will be necessary to use magnetic tape with a thickness of 10.5 μm or less, which is currently used, and this problem of shape transfer will become more and more serious. Conceivable. As a countermeasure, increasing the post diameter may be considered, but even the current 8 mm format has a diameter equivalent to 6 mm, and if the post diameter is increased too much, the cassette half will become larger.

In the conventional cassette half, there is a problem in that when a thin magnetic tape is used, stable signal recording and reproduction cannot be performed due to shape transfer by the post due to the post for ejecting the magnetic tape.

In order to solve the above problems, it is an object of the present invention to provide a cassette in which shape transfer does not occur.

Means for Solving the Problems In order to achieve the above object, the present invention provides a cassette half having a lid portion and four or more posts that contact the inside of the magnetic tape when the magnetic tape is stored and stored.

Operation According to the above-described structure of the present invention, the magnetic tape wraps around the post and the angle becomes smaller when the magnetic tape is stored and stored.

EXAMPLE Hereinafter, a cassette half according to a first example of the present invention will be described with reference to the drawings. FIG. 1 is a top view showing the structure of a cassette half according to a first embodiment of the present invention. In the figure, 7 is an unwinding reel, 8 is a take-up reel,
9 is the half body, 1° is the magnetic tape, 11 is the lid part,
12 is a post.

In the cassette half made of the above components, two posts are provided adjacently.

As is clear from the figure, the wrapping angle around the post can be made smaller than in the conventional example. In the first embodiment, a total of four posts, two each on the unwinding reel side and the take-up reel side, are used, so compared to the conventional example, the winding angle can be reduced to about 100 mm, and the post 12
shape transfer can be significantly improved. Also,
The magnetic tape can be easily pulled out by opening and closing the lid portion 11 in the same manner as in the conventional example.

As described above, according to the cassette huff according to the first embodiment of the present invention, by having a magnetic ted part when storing a magnetic tape, shape transfer by a post can be prevented, and the magnetic tape can be easily pulled. I can do it.

A cassette half according to a second embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a top view showing the structure of a cassette huff according to a second embodiment of the present invention, and 13 is a post. The post 13 has a steep cross section with two or more force points, a gently curved surface and a flat surface, and has a smaller contact angle than a round cross section. The difference from FIG. 1 is that the number of posts is small, and one post 13 has the same effect as the two posts 10 in FIG.

In this way, by using a post with a cross-sectional shape that connects two or more steeply curved surfaces with a gentle curved surface and a flat surface, one post can effectively reduce the This reduces the wrapping angle and prevents shape transfer.

In the first embodiment, the number of posts in contact with the inner side of the magnetic tape was four, but it goes without saying that the larger the number of posts, the greater the effect of reducing the wrapping angle, and the better the shape transfer.

In addition, in the second embodiment, absolute curvatures are not particularly specified for steep curved surfaces and gentle curved surfaces, but since steep curved surfaces correspond to the Bonuto diameter, the curvature radius is about 1 to 6 degrees. For gently curved surfaces, a radius of curvature of approximately 5 fins or more is considered appropriate.

Effects of the Invention As is clear from the above embodiments, four or more posts are provided inside the cassette body around which the tape is wound, and the arrangement of the posts is such that the contact angle is gentle when storing the magnetic tape. By doing so, it is possible to obtain excellent effects such as reducing the influence of shape transfer by the posts, and by providing a lead portion, it is possible to easily take out the magnetic tape.

[Brief explanation of drawings]

FIG. 1 is a top view showing the structure of the cassette half according to the first embodiment of the present invention, FIG. 2 is a top view showing the structure of the cassette half according to the second embodiment of the present invention, and FIG. 3 is a top view showing the structure of the cassette half according to the second embodiment of the present invention. It is a top view showing the structure of a half. Completion: Winding reel, 8: Take-up reel, 9: Half body, 10: Magnetic tape, 11: Lid section, 12 −・・−Post. Name of agent: Patent attorney Shigetaka Awano and one other person Figure 1? 7--lki81! (Thorn-1 and 8-flea, Sa1 and female-IL)l:i Figure

Claims (2)

[Claims] (1) A magnetic tape is wound inside a case consisting of a cassette half main body consisting of five sides and a lid part that can be opened and closed while covering the opening of the main body, and wound onto a reel and a take-up reel. and storing four or more posts for guiding the magnetic tape inside the cassette half;
The cassette half is arranged such that the post is located inside the winding of the magnetic tape when storing the magnetic tape, and the contact angle of the magnetic tape is made smaller than when using one post. (2) The magnetic tape is wound on an unwinding reel and a take-up reel inside a case consisting of a cassette half main body consisting of five sides and a lid part that can be opened and closed while covering the opening of the main body. A post for guiding the magnetic tape is provided inside the cassette half, and the post has a cross section such that a contact angle of the magnetic tape is smaller than that of a post having a circular cross section when the magnetic tape is stored and stored. Cassette half.