JPS5814629Y2 - Magnetic curtain in shield room - Google Patents

Description

[Detailed description of the invention] This invention is mainly composed of Fe, Co, Ni, Si, and B, and has high magnetic permeability and conductivity, is corrosion resistant, and has high elasticity.
Regarding the magnetic curtain of the shield room, which covers the entire surface of the entrance and exit of the shield room and through-holes with a sheet made of woven thin amorphous metal tape that is resistant to bending and mechanical distortion, and is attached so that it can be opened and closed. The purpose is to shield magnetic disturbances from inside and outside the shield room.

It is used as a shield room for various types of experimental measurements to shield unnecessary external electromagnetic waves from various high-frequency electrical devices and trains, earth's magnetism, and electromagnetic waves emitted from internal devices under test.

These shielded rooms contain personnel, ventilation, and lighting.

Since doors and through holes are provided for the entry and exit of measurement cables, electromagnetic intrusion and leakage occur here.

Conventionally, doors and shields were used to prevent magnetic intrusion and leakage.
I tried to reduce the gap between the rooms by using the force of a spring to make them close together, but the effect was not sufficient.

In addition, entrances and exits and through holes have been shielded with radio wave absorbing sheets, but although radio wave absorbing sheets are sufficiently effective in shielding high frequency magnetic fields, they have no effect at all in shielding DC magnetic fields. It has shortcomings.

In order to eliminate such drawbacks of the conventional method and enhance the shielding effect, the present invention covers entrances and through-holes with a magnetic curtain constructed by weaving thin tapes of amorphous metals mainly composed of Fe, Co, Ni, Si, and B. This relates to magnetic curtains for shielded rooms.

This invention was published in Japanese Patent Application No. 51-11579 (Japanese Unexamined Patent Publication No. 53-43
Fe, Co, Ni, S as shown in No. 028)
The main components are i and B, and the composition has an atomic ratio of 3 to 12% Fe, 50% or less Ni, 20% or less Si, and B.
is 5 to 25% (however, the total of Si and B is 20 to 35%)
), the remainder being Co, and relates to a magnetic shielding curtain for a shield room constructed by weaving an amorphous metal tape consisting of Co.

This material has high magnetic permeability and conductivity, is corrosion resistant, has high elasticity, and is resistant to bending and mechanical strain, making it extremely suitable for magnetic seals.

Table 1 shows an example of the properties of this material. As is clear from Table 1, this material has a saturation magnetic flux density Bs of 7,100G.
auss, coercive force Hc is 4m0e, magnetostriction λS is 0.2X
10-6 or less, and the permeability μe is 30 in the east
,000, for direct current magnetism and high frequency magnetism,
Furthermore, since the electrical resistance ρ is as small as 134 μΩ·cm, it is an effective magnetic shielding material against high frequency magnetism.

The present invention is applied to a shield room 1 equipped with an entrance/exit door 2 equipped with a handle 3 and a hinge 4 as shown in FIG.
As shown in the embodiment shown in the figure, a sheet 5 woven from amorphous metal is attached along curtain rails 6 provided above and below the doorway to cover the doorway 2 so as to be able to open and close from side to side.

The sheet 5 is preferably large enough to cover at least twice the gap between the sheet 5 and the shield room 1 so that most of the magnetic energy leaking from the gap between the sheet 5 and the shield room 1 can be shielded. .

FIG. 4 shows an embodiment of the present invention in which a through hole in a shield room is shielded. A magnetic sheet 5 is attached to a curtain rail 6 so that the curtain can be opened and closed.

The sheet 5 used for shielding the shield room 1 has a thickness Q of 1 mm or less and a width of 0.5 mm to 2 m, as shown in FIG.
The amorphous metal tape of m is a horizontal tape 8 and a vertical tape 9.
By weaving these together, a mechanically strong and flexible network structure is created.

As mentioned above, it is made by weaving thin tapes of amorphous metals mainly composed of Fe, Co, Ni, Si, and B into a net shape.It has high magnetic permeability and extremely low electrical resistance, and is also corrosion resistant, elastic, and flexible. The shield room, which uses a magnetic shielding sheet with high mechanical strength, is capable of shielding not only conventional high wave magnetic fields but also direct current magnetic fields, and can be easily installed in the opening of the shield room.

[Brief explanation of the drawing]

Figure 1 is a front view looking at the entrance and exit of the magnetically shielded room.
Figure 2 is a front view of the entrance/exit of the shield room using the present invention using an amorphous metal net-like magnetic shielding sheet, Figure 3 is a side view of the entrance/exit of the shield room shown in Figure 2, and Figure 4 is a side view of the entrance/exit of the shield room shown in Figure 2.
The figure shows a cross-sectional view of a through hole shielded by a magnetic shielding sheet, and FIG. 5 shows a partial plan view of a magnetic shielding sheet constructed by weaving an amorphous metal tape. In the diagram: 1: Shield room, 2: Entrance/exit door, 3
: Handle, 4: Hinge, 5: Sheet, 6: Curtain rail,
7: through hole, 8: horizontal tape, 9: vertical tape, 1a: outer layer, 1b: inner layer.

Claims (1)

[Scope of utility model registration request] A magnetic sheet made by weaving amorphous metal tape with high magnetic permeability and electrical conductivity, mainly composed of Fe, Co, Ni, Si, and B, into a net shape for the entrance and exit of the shield room.
A magnetic curtain for the shield room that covers the through-hole opening so that it can be opened and closed.