JPS5864680A - Cassette half - Google Patents

Abstract

PURPOSE:To improve the shielding properties of a cassette half by using synthetic resin, which contains silicon carbide and carbon powder having radio wave absorbability, as a material. CONSTITUTION:A casette half A has the combined structure of half bodies 1 and 2 formed of synthetic resin in one body, and the synthetic resin uses ABS, acrylic resin, etc. This synthetic resin is obtained by mixing silicon carbide powder independently, or silicon carbide powder with carbon powder of graphite, carbon black, etc., and then formed thermally in a mold. The blending ratio of the resin, silicon carbide, and carbon is 10-30% according to the kind of a tape and the extent of shielding, and the blending ratio of silicon carbide and carbon is 1.0:(0.0-0.3). Because carbon has lubricity, an incease in the mixing ratio of carbon improves, specially, a run of the tape.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cassette half made of silicon carbide powder or a synthetic resin containing a mixture of silicon carbide powder and carbon powder.

Generally, cassette halves such as compact cassettes, micro cassettes, video cassettes, etc. are molded products of synthetic resin, but when using them, the internal magnetic tape is susceptible to external radio waves, and conversely, the magnetic tape There is also the problem that the movement of the camera introduces noise to the outside. However, there are no shielding cassette halves designed to suppress the influence of radio waves.

Therefore, the present invention utilizes silicon carbide powder or a synthetic resin that is a mixture of silicon carbide powder and carbon powder as a material, and utilizes the radio wave absorbing properties of silicon carbide and carbon to realize a cassette half with good shielding properties. It is something.

The present invention will be explained in detail below based on embodiments shown in the drawings.

The figure shows the assembled state of cassette half A, which has a structure in which halves 1 and 2 obtained by integral molding of synthetic resin are combined. The synthetic resin material used is ABS, acrylic resin, etc., and the manufacturing method is to use silicon carbide powder alone or to mix silicon carbide powder with carbon powder such as graphite or carbon black, and heat mold this in a mold. The blending ratio of resin, silicon carbide, and carbon is not constant depending on the type of tape to be accommodated and the degree of shielding required, but it is in the range of 10% to 30% (weight ratio), and the blending ratio of silicon carbide and carbon is Although the ratio is not specified, it is in the range of 1.0 to O1O to 0.3 (weight ratio). In particular, since carbon has slipperiness, increasing the mixing ratio of carbon has the advantage of making the tape run more easily.

Further, in order to improve the shielding properties, a single molded body of the above-mentioned synthetic resin may be coated with a resin paint containing silicon carbide powder or silicon carbide powder and carbon powder. In this case, the paint used is acrylic, epoxy, etc., and the blending ratio of paint and silicon carbide or carbon is 10% to 20% (by weight).
It is.

Next, examples of the present invention will be specifically described.

[Example 1] Silicon carbide powder with an average particle size of 10 μm was mixed into ABS at a weight ratio of 9:1, and this was heated and molded in a mold to form a half-piece, and the upper and lower half-pieces were combined to form a cassette half. Assembled.

[Example 2] ABS was mixed with silicon carbide powder and carbon black with an average particle size of 10μ at a weight ratio of 6.5:3:0.5,
This was molded in the same manner as in Example 1, and then a cassette half was assembled.

[Example 3] An epoxy resin paint containing 10% wt of silicon carbide powder with an average particle size of 10 μm was applied to the surface of a semicircle molded from ABS and acrylic to a thickness of about 0.1 mm. I used that half day off to assemble half a cassette.

[Example 4] Approximately 40% wt of silicon carbide powder with an average particle size of 10 μm and carbon black with an average particle size of 10 μm were mixed into the surface of a half-housing molded with ABS and acrylic resin at a blending ratio of 3:1. The epoxy resin 3111 paint was applied to a thickness of about 1/2 inch, and the cassette halves were assembled by combining the half coats.

When the cassette half obtained in each of the examples above was loaded into a tape recorder and tested for recording and playback, it was possible to listen to clear reproduced sound without any turbidity in the auditory sense.

[Brief explanation of the drawing]

The drawing is a perspective view of one embodiment of the invention.

Claims (1)

[Claims] (11) A cassette half made of a synthetic resin mixed with silicon carbide powder. (2) A cassette half made of a synthetic resin mixed with silicon carbide powder and carbon powder.