JPH05136596A - Floor magnetic shield device - Google Patents

Abstract

PURPOSE:To obtain a floor magnetic shield device which is enhanced in workability and profitability by a method wherein flooring material possessed of magnetic shield function is laid on a floor surface as floor finishing material. CONSTITUTION:An amorphous ribbon 1 is sandwiched between a molded plastic tile surface layer 2 and a plastic main material 3, which is formed into one piece with adhesive agent for the formation of a magnetic shield flooring material A. Or, through-holes are provided to the amorphous ribbon 1, and the amorphous ribbon 1, the surface layer 2, and the plastic main material 3 are welded together through the through-holes. The magnetic shield flooring material A composed as above is tightly laid on a floor surface, and the plastic tile main material 3 is pasted on a base B of mortar or concrete through the intermediary of an adhesive layer 4. Magnetic line of force 5 arriving from below is absorbed by the magnetic shield flooring material A. By this setup, as compared with a conventional method where equipments are separately, magnetically shielded, all the floor surface can be lessened in magnetism, so that a countermeasure is not required to be taken into consideration again even if a new equipment is installed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic shield device for a floor surface which prevents magnetic fields from leaking from an underground transformer room or a machine room to the floor surface of an upper floor and adversely affecting precision instruments.

[0002]

2. Description of the Related Art In recent years, equipment installed in office buildings typified by intelligent buildings, precision plants in which clean rooms are installed, and the like are increasingly sensitive to magnetism. Of these, special equipment that dislikes magnetism, such as electron microscopes, is equipped with a magnetically shielded room to provide a high degree of magnetically controlled space, but generally, unless a strong magnetic field source is nearby, At present, it is installed at the required position without any measures taken.

However, some of these devices have an adverse effect even on weak magnetism of several G (Gauss). For example, in a CRT for a computer, the screen may be distorted or color misregistration may occur even at the level of IG. Furthermore, if it is an alternating magnetic field, even about 30 mG (milligauss) will cause a problem. On the other hand, in the present everyday environment, various magnetic sources are present nearby. For example, large magnetism is generated around a train, a car, a power transmission line, or the like, and when a building is built nearby, an environment-changing magnetic field of several tens of mG exists. Further, a substation room is often provided in the basement of a building, but there is a large fluctuating magnetic field (AC magnetic field) of about several hundred mG directly above it. The precision equipment installed here is exposed to a bad magnetic environment, and the performance of the equipment cannot be exhibited satisfactorily.

As described above, the problem of the magnetic field that fluctuates with the environment, particularly the problem of the magnetic field generated from the floor, is becoming a very important issue in modern society. Fig. 4 is an example of actual measurement of the magnetic field generated from the floor surface in the clean room of a precision factory. It is a plane distribution map of the magnetic field at a height of 25 mm from the floor measured by field measurement. It is distributed irregularly in.

Generally, the following five points can be considered as sources of the magnetic field leaking onto the floor surface in the building. (A) Remanent magnetism of ferromagnetic materials such as reinforcing bars, steel frames, and bolts that are building structural materials (b) Magnetism generated from electric equipment such as power lines (c) Magnetism leaked from substations and machine rooms below ( ) Magnetism generated from permanent magnets accidentally embedded in concrete (e) Magnetism generated from permanent magnets and coils in equipment (f) Magnetism due to stray currents flowing through equipment pipes and reinforcing bars, among which (a) The magnetic field of No. 29 does not newly occur once degaussed.
It can be removed by 8957 (automatic degaussing device on the floor). However, since (b) to (f) permanently generate magnetism, there is no way to completely eliminate it by removing the source itself, and an effective solution that can be easily implemented without changing the current configuration is , Currently, there is no such thing, but replace the precision equipment with a place where the influence of magnetism is small, or conversely, place the magnetic source far away or put a magnetic shield around the equipment. is there.

[0006] Especially for the magnetic field leaking from the underground substation room or the machine room in the building of (C) where a large magnetic field is generated, the CRT is buried deep in the substation or used on the first floor which is the upper floor. The current situation is that individual magnetic shields are applied to each of the above.

[0007]

As described above, the magnetism generated from the floor surface, particularly the magnetism leaking from the underground substation room or the machine room to the first floor immediately above, has a great influence on precision equipment. However, the countermeasure is only to magnetically shield precision equipment, not to reduce the overall magnetism. It is not a fundamental solution to the problem. If you insert a new device, you have to think about the measures again,
Depending on the device, individual magnetic shields may not be possible.

Further, in the case of an underground substation room, a machine room, etc., the source of magnetism may be placed far away and a distance attenuation effect may be used as a countermeasure, but the layout change also affects the shape of the building. It also leads to higher costs. Also, a means such as magnetically shielding the floor surface may be considered. This is a magnetic shield that covers the floor surface with a ferromagnetic material such as permalloy, amorphous silicon steel plate, and pure iron, and absorbs the invading magnetic field to prevent invasion of magnetism. However, in this method, a magnetic shield layer is separately provided under the floor finishing material, which is troublesome and it is not easy to obtain the accuracy of the floor surface, and the cost is increased accordingly.

Under such circumstances, there is a demand for a means for easily and effectively reducing the magnetism generated from the floor surface, particularly the magnetism leaking from the underground substation room or machine room to the floor directly above.
The present invention has been proposed in view of such circumstances, and an object of the present invention is to provide a magnetic shield device for a floor surface, which has improved workability and is excellent in economic efficiency.

[0010]

In order to achieve the above object, a floor magnetic shield device according to the present invention is constructed by laying on the floor surface as a floor finishing material of a floor material having a magnetic shield function. There is.

[0011]

According to the present invention, as described above, the floor finishing material having the same shape as the conventional one has a magnetic shield function, and by laying the floor finishing material on the floor surface, the leakage magnetic field on the floor surface is cut off. Therefore, the magnetic shield floor can be easily constructed by the conventional method without requiring special labor.

Further, according to the present invention, not only the magnetism leaking from the underground substation room or the machine room but also the temporary magnetism or permanent magnetism from another source can be removed.

[0013]

The present invention will be described below with reference to the illustrated embodiments. A is a magnetic shield floor material, and as shown in FIG. 2, the amorphous ribbon 1 is sandwiched between the molded plastic tile surface layer 2 and the plastic tile main material 3 and is integrated with an adhesive. Has been done. Alternatively, it is also possible to provide a through hole at each appropriate portion of the amorphous ribbon 1 and weld through the through hole. The diameter of the through holes is about 10 mm to 20 mm, and if they are separated by about 100 mm, there is no fear of magnetic leakage. In order to reduce the gap in the amorphous ribbon 1, the edge face is assumed to extend to the end of the floor material. The number of sheets is determined according to the target magnetism.

The commercially available amorphous ribbon has a maximum width of 200 mm, but at the laboratory level, an amorphous ribbon having a width of 300 mm or more has been manufactured. As long as there is a production line, it is possible to sandwich a single amorphous ribbon with a width of 303 mm in a plastic tile in a state where it can be produced. Even if only 200 mm width can be used, it can be used by stacking them. In this case, it is necessary to take care that the overlapping width is 50 mm and that the overlapping position is shifted so that the seams are not concentrated.

FIG. 3 shows another embodiment of the floor material 3, which is composed of an amorphous mixed plastic tile 3'molded by mixing amorphous flakes or amorphous powder with a resin which constitutes the floor material. .. The amorphous powder is uniformly mixed in the resin, and the mixed amount is determined according to the target magnetism. Thus, the magnetic shield floor material A configured as described above is spread on the floor surface, and the plastic tile main material 3 of the floor material A is attached to the base B of mortar or concrete via the adhesive layer 4.

Magnetic shielding is performed by the magnetic shield floor material A so as to absorb the magnetic force lines 5 from under the floor.
The standard size of the plastic tile constituting the magnetic shield floor material A is 303 mm × 303 mm, and joints 6 are formed at the joints, but since the magnetic shield layer extends to the end of the floor material, the gap is almost eliminated. It almost disappears and the leakage of magnetism can be suppressed to a small level.

INDUSTRIAL APPLICABILITY The present invention is applied in order to prevent a magnetic field from leaking from an underground substation room or a machine room in a building to the floor surface of an upper floor, which may adversely affect precision equipment. It is related to the magnetic shield on the floor surface, and it is not a precision instrument that is sensitive to magnetism and does not require an ultra-precise magnetic environment such as an electron microscope. Instead, a magnetic shield is conventionally provided such as a CRT. It is intended for devices that do not have or have individual magnetic shields.

The magnetism leaking from the substation room or machine room on the floor directly below is transmitted to the upper floor through the floor surface. Therefore, if the floor surface is magnetically shielded as in the above embodiment, the magnetism can be efficiently removed. The target leakage magnetism is a variable magnetic field (AC magnetic field) of several 100 mG, which is reduced to about 30 mG which is a problem in CRT. In this embodiment, a flooring material having a magnetic shield function is used as a floor finishing material, and by laying it on a target floor, it is possible to cut off a leakage magnetic field on the floor surface.
Since the floor finishing material, which has the same shape as the conventional one, has a magnetic shield function, it can be installed without any special effort.

Next, the reason why amorphous is used as the material for the magnetic shield will be described. Amorphous permalloy silicon steel sheet is suitable in terms of magnetic performance when the target magnetic field is the above. These exhibit high magnetic permeability in a low magnetic field and have excellent characteristics against an alternating magnetic field. However, Permalloy cannot be applied to a place such as a floor where a constant load is applied, because the magnetic characteristics deteriorate due to stress strain. Further, the silicon steel sheet cannot exhibit the characteristics in a thin state, and becomes heavy when it is thick. Therefore, amorphous is optimal because it is thin and light and does not cause deterioration of magnetic properties due to stress.

Amorphous is an amorphous metal or alloy formed by quenching iron or cobalt and has a thickness of 25 μm.
It is a degree. Commercially available as a thin film ribbon (for example, METALGLAS of Japan Amorphous Metal), flakes made by the cavitation method (for example, Riken amolic flake), and powder (for example, Riken amolic powder). Has been done.

[0021]

According to the present invention, as described above, a floor material having a magnetic shield function is laid on the floor surface as a floor finishing material, so that the floor surface can be individually shielded from the precision equipment. Since the overall magnetism can be reduced, it is not necessary to consider measures again even if a new device is inserted, and it can be applied to devices that cannot individually shield the magnetic field.

Compared with the case where a separate magnetic shield layer is provided on the floor, the present invention provides a magnetic shield function to the floor finishing material itself having the same shape as in the conventional case, so that the conventional case can be realized without any special effort. It can be installed easily by the same method, which leads to cost reduction. Furthermore, it is possible to remove not only the magnetism leaking from the underground substation room or the machine room, but also the temporary magnetism or permanent magnetism from another source.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing an embodiment of a magnetic shield device for a floor according to the present invention.

FIG. 2 is a vertical sectional view showing an example of a magnetic shield flooring material.

FIG. 3 is a vertical cross-sectional view showing another embodiment of the floor material.

FIG. 4 is an example of actual measurement of magnetism generated from the floor surface.

[Explanation of symbols]

 A Magnetic shield floor material B Base 1 Amorphous ribbon 2 Plastic tile surface layer 3 Plastic tile main material 3'Amorphous mixed plastic tile main material 4 Adhesive layer 5 Magnetic field lines 6 Joints

Claims (5)

[Claims] 1. A magnetic shield device for a floor surface, wherein a floor material having a magnetic shield function is laid on the floor surface as a floor finishing material. 2. The flooring material having a magnetic shield function,
The floor magnetic shield device according to claim 1, wherein the amorphous ribbon is sandwiched between upper and lower molded materials in a sandwich shape. 3. The flooring material having a magnetic shield function,
The floor magnetic shield apparatus according to claim 1, wherein the amorphous flakes are sandwiched between upper and lower molded materials in a sandwich shape. 4. The flooring material having the magnetic shield function,
The magnetic shield device for a floor surface according to claim 1, which is molded by mixing amorphous flakes in a resin forming a base material of the floor material. 5. The flooring material having the magnetic shield function,
The magnetic shield device for a floor surface according to claim 1, which is molded by mixing amorphous powder into a resin that constitutes a base material of the floor material.