JPS5815300A - Cover for preventing radio wave defect - 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 The present invention relates to a covering for preventing radio wave interference in electric discharge machining equipment and the like.

In electrical discharge machining equipment and the like, radio wave interference is a problem caused by radio waves generated during electrical discharge. In particular, wire-cut electric discharge machining equipment a uses a high voltage, and the electric field strength of the radiated radio waves is strong and the frequency range is wide, causing radio wave interference to surrounding television receivers and the like.

Conventionally, a shield room shown in FIG. 1 has been used as a means to prevent this radio wave interference.

In Fig. 1, (1) is a shield room, (2) is an electrical discharge machine housed in this shield room (1),
For example, in the wire-cut electrical discharge machining apparatus, (3) is the opening/closing door of the shield room (1). -Heki Sea Dorm (1)
) is generally constructed of a metal plate with high radio wave reflection efficiency such as a copper plate, and wire-cut electrical discharge machining equipment (
However, this shield room (1) has the following drawbacks. That is, in general, the separation between metal plates, side walls and opening/closing doors (3)
It is difficult to maintain sufficient airtightness at the mating part,
Because radio waves leak through this small gap, the effectiveness of the shield room (1) may be halved. Copper is the most commonly used metal plate, and although this material has extremely high radio wave reflection efficiency, its absorption efficiency is close to black, meaning that the radio waves radiated from the radio wave source are reflected internally. This is because, as mentioned above, if there is a small gap, most of the radio waves will leak out from that part. Furthermore, the shield room (1) must be made solid and is fixedly installed at an appropriate location within the factory, which creates difficulties when moving the equipment.

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional products, and uses cloth made of flexible fibers coated with a conductive material to form, for example, a tent shape, and is used to create a wire-cut electric discharge machining device that is a source of radio waves. The object of the present invention is to provide a covering for preventing radio wave interference that is easy to handle and prevents radio wave interference by covering the area.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 shows a part of the covering (4) made from a cloth made by coating glass fibers with nickel vf coating and bundling the fibers into a plain weave. The covering body (4) shown in Fig. 2 covers a rectangular parallelepiped (5) made of a framework of aggregates such as iron or aluminum as shown in Fig. 8, and its entrance and exit (6) are connected to the covering body (4). It has a structure in which the two are superimposed. The above covering (
4) is made of glass fiber, so it is highly flexible and has excellent fire resistance. However, when it is applied to wire-cut electrical discharge machining equipment, etc., which does not pose a risk of fire, it is recommended to use glass fiber, etc. Also good. In addition, after making glass fiber into a plain weave, it may be coated with nickel, etc. The coating material, which is a conductive substance, may be mixed with a material with a high radio wave absorption effect, such as ferrite, and conductive carbon, etc. It may also be used as

Next, the radio interference prevention principle of the covering (4) according to the present invention,
and its characteristics.

Although a conductive metal plate is used in the above-mentioned general shield room (1), the same effect can be obtained by using a fine wire mesh. This is because if the eye fMJ is sufficiently hidden from the wavelength of the radio wave to be shielded, the radio wave will not be able to pass through.

The cloth constituting the radio wave interference prevention covering (4) 41- according to the present invention is made of a cloth that is sufficiently finer than the wavelength of the target radio waves, for example, the TV Gene radio waves, so that at least the TV Gene radio waves can be transmitted. It has a sufficient shielding effect against radio waves with wavelengths longer than . Furthermore, by using nickel as the conductive material, the radio wave absorption efficiency is significantly improved, so that the radio wave absorption efficiency from the radio wave generation source such as the wire-cut electric discharge machining device (2) placed inside the covering body (4) is Most of the radio waves are absorbed by the covering (4) and only a portion is reflected. Therefore, when the covering body (4) is assembled as shown in Fig. 8, the covering body (4) becomes the entrance/exit (6).
) If the width of the overlapping portion is sufficiently large, the amount of radio waves leaked will be significantly reduced even if they are not in perfect contact, and the shielding effect will be sufficient.

Furthermore, since the radio wave interference covering (4) according to the present invention is light in weight, it is easy to move and has excellent ventilation, which improves the working environment. Furthermore, since the internal devices can be seen from the outside, it is convenient for monitoring automated machines such as wire-cut electric discharge machining equipment. In addition, the price is lower than that of a shield room, etc., and the covering (4
) It has the advantage of being easy to maintain, as it is only necessary to attach the fabric that makes up the structure.

In the above explanation, the case where the present invention is applied to prevent radio wave interference in electrical discharge machining equipment is illustrated and explained.
It goes without saying that the present invention is not limited to this, and can also be applied to other mechanical devices.

As described above, according to the present invention, a fabric roughly coated with a conductive material is used as a covering for preventing radio wave interference, and is used to protect machines that generate interference radio waves and those that receive interference radio waves. By coating a machine that does not like it, it has the effect of producing an inexpensive product that has a great radio wave shielding effect, is easy to move, easy to handle and maintain, and has excellent air permeability.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of a conventional shield room, Fig. 2 is an enlarged view of a covering body which is an embodiment of the present invention, and Fig. 3 is a diagram of an embodiment in which the covering body according to the present invention is specifically used. It is. In the figure, (1) is a u-shield room, (2) is a wire-cut electrical discharge machining device, and (4) is a covering for preventing radio wave interference. Note that the same reference numerals in the figures indicate the same or equivalent parts. Agent Shin Kuzuno −

Claims (4)

[Claims] (1) A covering for preventing radio wave interference, which is made by coating flexible fibers with a conductive substance. (2) The covering for preventing radio wave interference according to claim 1, wherein the flexible fiber is a flame-retardant material. (3) The covering for preventing radio wave interference according to claim 1 or 2, wherein the conductive substance is mainly composed of nickel. (4) Conductive Materials Co., Ltd. Claim 1, characterized in that the main components are carbon and ferrite.
The covering for preventing radio wave interference according to item 1 or 2.