JPH06140783A - Amorphous magnetic shield plate and magnetic shield technique - Google Patents

Abstract

PURPOSE:To provide a magnetic shield material which is easy to handle and has high magnetic shield performance. CONSTITUTION:An amorphous magnetic shield plate A is formed by laminating a plurality of layers of amorphous ribbons 2 in a silicon steel plate 1, by covering the lamination with a resin film 3, and by depressurizing an interior of the resin film to a vacuum pack. In a magnetic shield technique, a number of amorphous magnetic shield plates A are arranged like the same plane, and arranged so that a joint 4 of adjacent clearances of amorphous magnetic shield plates A' arranged thereon does not coincide with a joint 4 between amorphous magnetic shield plates arranged therebelow.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an amorphous magnetic shield plate for a magnetic shield room and a magnetic shield construction method installed for the purpose of shielding a fluctuating magnetic field of disturbance and protecting internal equipment.

[0002]

2. Description of the Related Art Recently, many devices installed in intelligent buildings and precision factories are sensitive to magnetism. For example, the electron microscope is designed to suppress the magnetic fluctuation component to 2 milligauss or less in order to increase the sensitivity. In addition, even general OA equipment may have an adverse effect on weak magnetism such as several Gauss. For example, a CRT for a computer may have a distorted screen or a color shift even at about 1 Gauss. Furthermore, if it is an alternating magnetic field, even about 10 milligauss will be a problem.

On the other hand, in the present everyday environment, various magnetic sources are present nearby. For example,
Large magnetism leaks around trains, cars, power lines, etc. When a building is built nearby, there is a fluctuating magnetic field of about several tens of milligauss. The precision equipment installed therein will be exposed to a magnetically adverse environment, and it will no longer be possible to demonstrate the performance of the equipment satisfactorily. As a countermeasure against this, enclose the surroundings of the equipment or the entire room in which the equipment is installed with a ferromagnetic material such as permalloy, amorphous, silicon steel plate, pure iron, etc. to prevent the invasion of magnetism by absorbing the invading magnetic field from the outside. The method of installing the magnetically shielded room is adopted.

The magnetic shield room has a great difference in performance and cost depending on the magnetic material used, the construction method, etc., and the optimum one is selected according to the purpose. Conventionally, it is made of permalloy that has been used for a high-performance magnetically shielded room, and a higher effect can be expected if a two-layer or three-layer structure is used. However, permalloy has the drawback that its magnetic properties are greatly deteriorated by stress, and it requires careful attention not only during processing but also during construction and use, making it difficult to use for general buildings. In addition, there are major restrictions on costs.

Therefore, recently, a magnetic shield room construction method using an amorphous material, which has a magnetic permeability higher than that of permalloy and has little deterioration of magnetic characteristics due to stress, has been attracting attention. Amorphous is an amorphous metal or alloy formed by quenching iron or cobalt. The material used for the magnetic shield material is a ribbon in the form of a foil (for example, METGLAS of Japan Amorphous Metal), or a flake alloy made by the cavitation method in the form of a sheet (for example, Riken's amolic sheet). Is provided. These are more advantageous than permalloy in terms of cost. It should be noted that silicon steel sheets and pure iron are largely inferior to permalloy and amorphous in terms of magnetic characteristics, and are generally used in combination with other materials.

[0006]

Sheet-shaped flaky alloy pieces of the prior art described above are materials that are widely used at present, but on the other hand, they have the advantage that they can be freely formed, but even if several layers are stacked. There is a gap between the flakes and the magnetic resistance due to the discontinuity of magnetism is large, so that the initial performance cannot be obtained. As a result, it is often used in combination with a silicon steel sheet, and although some magnetic shielding effect is recognized, it is hard to say that it utilizes the original amorphous characteristic of high magnetic shielding performance in a low magnetic field region. .

On the other hand, in the case of the above-mentioned ribbon which is a foil-shaped band, since it is a dense foil with no gaps, it is possible to make use of the original characteristics of the amorphous material as compared with the case where the flake-shaped alloy piece is made into a sheet shape. . However, there are many problems to be solved in order to fully exhibit the characteristics of the ribbon, which is a foil strip. The foil is usually about 25 μm thick, and it is necessary to stack a considerable number of sheets in order to enhance the magnetic shield effect without magnetic saturation. In addition, the maximum width that can be manufactured at present is 220 mm, and when a large flat surface is magnetically shielded, a lot of seam processing is required, which is a great labor for manufacturing, and the hand is cut by an edge during handling. Is dangerous and is difficult to manage on-site.

Therefore, a method is also used in which a required number of amorphous ribbons are attached to plaster boards at the factory and attached as unit plates on site, but there are various manufacturing problems such as seam treatment between unit plates. In addition, although iron-based amorphous is often used because of its cost advantage, iron has a problem of rusting, and amorphous has a tendency to largely deteriorate in magnetic characteristics due to rusting. As described above, the amorphous ribbon, which is a foil-shaped band, is expected as a main material for general magnetically shielded rooms, but its poor handling has slowed its widespread use. A new construction method was desired. Therefore, an object of the present invention is to provide a magnetic shield material that is easy to handle and has high magnetic shield performance.

[0009]

Means for Solving the Problems The present invention has achieved the above object, and an amorphous magnetic shield plate is obtained by laying a plurality of amorphous ribbons on a reinforcing plate such as a silicon steel plate in a planar manner in a plurality of layers without gaps. The laminated reinforcing plate and the plurality of layers of planar amorphous are covered with resin films on the upper and lower surfaces and the peripheral portion, and the inside covered with the resin film is decompressed to form a vacuum pack.
In the case of a plurality of layers of planar amorphous, it is preferable in terms of magnetic shield that the longitudinal direction of the amorphous ribbon and the bonding boundary position are changed in the vertically adjacent layers so that the bonding boundary lines of the amorphous ribbon do not overlap in the upper and lower layers. . According to the magnetic shield method of the present invention, a large number of the above-mentioned amorphous magnetic shield plates are arranged on the same plane to form a first magnetic shield surface, and then a large number of magnetic shield plates are arranged on the first magnetic shield surface to form a second magnetic shield. When the surface is formed, the shield plates of the second shield surface are arranged so that the joints between the amorphous magnetic shield plates of the first shield surface and the second shield surface do not match.

[0010]

The above-mentioned amorphous magnetic shield plate can be made as a unit plate at the factory, and is formed by laying a plurality of thin amorphous ribbons flatly in a plurality of layers on a reinforcing plate such as a silicon steel plate. Since the ribbon is spread over the reinforcing plate, it has good workability and is easy to handle. In addition, since the directions of the amorphous ribbons in each layer are changed so that the adjacent boundary lines of the amorphous ribbons do not match vertically,
The magnetic shield property is high. Furthermore, since the reinforcing plate and the plurality of amorphous layers are covered with the resin film in a laminated state and the inside is evacuated, each iron-based amorphous ribbon does not rust. When a magnetic shield surface is formed using the above-mentioned amorphous magnetic shield plate, a joint between the magnetic shield plates forming the first layer,
Since the seams between the magnetic shield plates of the second layer do not coincide with each other, the magnetic shield performance is good.
If the magnetic shield plates are arranged in three or more layers, the magnetic shield property is further improved, and the number of the magnetic shield plates may be partially different.

[0011]

EXAMPLE An example of the amorphous magnetic shield plate of the present invention will be described with reference to FIGS. In the amorphous magnetic shield plate A, a plurality of amorphous ribbons 2 are laid in a plane shape on a silicon steel plate 1 without any gaps, and a resin film 3 covers the upper and lower surfaces of the laminate of the silicon steel plate 1 and a plurality of amorphous layers and the peripheral portion. The inside of the cover and bag-shaped resin film 3 is decompressed to form a vacuum pack. The thickness of the amorphous magnetic shield plate A thus formed in the unit plate shape is about 1 mm. The silicon steel plate 1 has, for example, a flat surface of 600 × 900 mm and a thickness of 0.35 to 0.5.
It is formed in mm. The silicon steel plate 1 serves as a reinforcing plate for laying the thin amorphous ribbons 2 in a planar shape, and also has magnetic shield performance. Therefore, instead of the silicon steel plate 1, the amorphous ribbon 2 can be kept flat and a plate material having a good magnetic shield property can be used. Amorphous ribbon 2 laid on top of silicon steel plate 1
For example, those having a width of about 220 mm are used, and they are spread on the upper surface of the silicon steel sheet 1 without any gap. The spread amorphous ribbon 2 is firmly adhered to the peripheral edge of the silicon steel plate 1 by a method such as fusion bonding.

A plurality of amorphous layers composed of the amorphous ribbon 2 are stacked, and in the embodiment shown in FIG.
It is layered. These three amorphous layers are arranged so that the junction boundary lines of the respective amorphous ribbons 2 do not coincide with each other in the upper and lower parts so that there is no magnetic leakage. For example, in the embodiment of FIG. 2, the first amorphous layer on the side of the silicon steel sheet 1 has the amorphous ribbons 2 arranged in the long side direction, and the second amorphous layer thereon has the amorphous ribbons 2 arranged in the short side direction. The third amorphous layer thereon is arranged in the same direction as the amorphous ribbon 2 of the first amorphous layer so as to be offset so that the boundary line positions do not overlap.

A method of constructing a magnetic shield wall using the amorphous magnetic shield plate constructed as described above will be described with reference to FIG. In this embodiment, two unit plate-shaped amorphous magnetic shield plates A are attached to the base wall. In order to construct the first layer, the amorphous magnetic shield plates A are arranged vertically and horizontally as shown in FIG. 3, and in this case, the adjacent amorphous magnetic shield plates A are arranged.
In between, a seam 4 is formed. Then, in order to construct the second layer, the amorphous magnetic shield plates A ′ of the first layer are stacked and the amorphous magnetic shield plates A ′ are arranged as shown in FIG. Although a seam is formed between them, the seam is arranged so as not to coincide with the seam of the first layer, and the magnetic shield performance is improved. Amorphous magnetic shield plate A
When stacking 3 or more layers, the amorphous magnetic shield plate A
Are arranged. Further, when the amorphous magnetic shield plates A are stacked, the number of stacked sheets may be partially different to meet the magnetic shielding situation.

[0014]

Since the amorphous magnetic shield plate of the present invention can be manufactured as a standard unit plate in which a plurality of amorphous layers are laminated on a reinforcing plate in a factory, it is highly reliable in performance and accuracy and can be handled in the field. It will be easier and the site management will be easier. Further, since the amorphous magnetic shield plate itself has a predetermined number of amorphous ribbons spread over each other without a gap, it exhibits the original high magnetic shield performance of amorphous. Further, since the amorphous magnetic shield plate is covered with a resin film and formed in a vacuum pack shape, the amorphous ribbon does not come into contact with air, and there is no problem of rust even in iron-based amorphous. In the magnetic shield method, since a plurality of layers are stacked so that the seams between the unit plate-shaped amorphous magnetic shield plates do not overlap each other, it is possible to construct a magnetic shield room without magnetic leakage from the gap.

[Brief description of drawings]

FIG. 1 is a sectional view of an amorphous magnetic shield plate of the present invention.

FIG. 2 is an exploded perspective view of an amorphous magnetic shield plate.

FIG. 3 is an explanatory diagram of a magnetic shield method.

[Explanation of symbols]

 1 Silicon steel plate 2 Amorphous ribbon 3 Resin film 4 Seam A Amorphous magnetic shield plate

Claims (3)

[Claims] 1. A plurality of amorphous ribbons are spread in a planar manner on a reinforcing plate such as a silicon steel plate in a plurality of layers without a gap, and the upper and lower surfaces and peripheral portions of the laminated reinforcing plate and the plural layers of planar amorphous are An amorphous magnetic shield plate, which is covered with a resin film, and the inside covered with the resin film is decompressed to form a vacuum pack. 2. The planar amorphous material having a plurality of layers is formed so that the longitudinal direction of the amorphous ribbon and the bonding boundary position are changed in the vertically adjacent layers so that the bonding boundary lines of the amorphous ribbon do not overlap in the upper and lower layers. The amorphous magnetic shield plate according to claim 1, wherein: 3. A magnetic shield construction method for arranging a plurality of amorphous magnetic shield plates according to claim 1 to construct a magnetic shield surface, wherein a plurality of amorphous magnetic shield plates are arranged on the same plane to form a first magnetic shield surface, and First
When forming a second magnetic shield surface by stacking a large number of amorphous magnetic shield plates on the magnetic shield surface,
A magnetic shield construction method characterized in that the shield plates of the second shield surface are arranged so that the joints between the respective amorphous magnetic shield plates of the shield surface and the second shield surface do not match.