JPH05327267A - Radio wave absorbing external wall panel - Google Patents

Abstract

PURPOSE:To make the production at plants possible, to increase an efficiency of an installation work, to increase a safety and a reliability of a radio wave absorbing performance. CONSTITUTION:The plurality of radio wave absorbing plates 2 which are formed by mixing a conductive fiber such as a carbon fiber into dielectric substance such as concrete are arranged in the most outer layer or behind an outer- packaging tile. The conductive fiber extends parallelly with an electric field of a radio wave to be absorbed. Behind the plurality of the radio wave absorbing plates 2, a conductive reflecting body 3 which is common to the plurality of the radio wave absorbing plates 2 is located. Or, the conductive reflecting body is fixed behind the conductive absorbing plates.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio wave absorbing outer wall panel that can be used as a building exterior material.

[0002]

BACKGROUND OF THE INVENTION Ghosts occur due to the reflection of television broadcasts by tall buildings. A typical prior art for solving this problem is constructed by adhering a radio wave absorber made of ferrite tile to the outer peripheral surface of reinforced concrete of a building. In such a prior art, since ferrite is used, it is expensive, has a large weight, and has a problem of high construction cost.

In another prior art, ferrite tiles are used to manufacture a panel structure in a factory in order to improve the efficiency and safety of the outer wall of a high-rise building. This prior art also uses ferrite and has the same problem as described above.

As a prior art for absorbing electromagnetic waves, one in which carbon powder is impregnated in a synthetic resin foam and used as an electromagnetic wave absorbing plate for an anechoic chamber has been put into practical use. However, in this prior art, it is extremely thick, and the shape is an assembly of pyramids, which is complicated, and therefore cannot be implemented as an exterior material of a building.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electromagnetic wave absorbing outer wall panel which improves efficiency of construction work, improves safety, and is excellent in reliability of electromagnetic wave absorbing performance. is there.

[0006]

According to the present invention, a plurality of electromagnetic wave absorbing plates are arranged side by side in the outermost layer or behind a finishing material, and each electromagnetic wave absorbing plate includes a dielectric substance and a conductive fiber. The conductive fiber extends parallel to the electric field of the radio wave to be absorbed, and a conductive reflector common to these radio wave absorption plates is arranged or lined behind the radio wave absorption plates. It is a radio wave absorption outer wall panel.

Further, the present invention is characterized in that the conductive reflector has a large number of through holes, and concrete is poured and fixed together with the radio wave absorbing plate.

Further, the present invention is characterized in that the conductive reflector is a reinforced concrete reinforcing bar provided behind the electromagnetic wave absorbing plate.

Further, according to the present invention, the finishing material is an exterior tile, and a radio wave absorbing plate is fitted in a recess formed behind the exterior tile, and the radio wave absorbing plate and the exterior tile are integrally formed with concrete. It is characterized by being configured.

[0010]

According to the present invention, the electromagnetic wave absorption outer wall panel can be manufactured in the factory and the conventional so-called precast reinforced concrete assembly panel method can be used, thus improving the efficiency of the construction work on site. In addition, the safety is improved, and the reliability of the electromagnetic wave absorption performance is further improved.

In the radio wave absorbing outer wall panel of the present invention, a plurality of radio wave absorbing plates are arranged side by side in the outermost layer, and the radio wave absorbing plate is made of a dielectric material such as concrete or synthetic resin and a conductive fiber such as carbon. And the like, the conductive fiber extends parallel to the electric field of the electric wave to be absorbed, for example, the electric field of the electromagnetic wave of television broadcasting, thereby improving the absorption of the electric wave of television broadcasting,
The thickness of the radio wave absorber can be reduced.

Behind a plurality of radio wave absorbers, a conductive reflector common to these radio wave absorbers is arranged, or a conductive reflector is integrally lined for each radio wave absorber. The thickness from the surface on the radio wave entrance side to the conductive reflector is set to, for example, about 1 / the wavelength of the radio wave inside them.
It is possible to cancel the incoming wave of the radio wave and the reflected wave of the conductive reflector by this, and prevent the reflection of the radio wave. The conductive reflector is arranged commonly to the plurality of radio wave absorbers,
This can facilitate manufacturing.

The conductive reflector may have a large number of through holes, and concrete may be poured and fixed together with the electromagnetic wave absorbing plate to form an outer wall panel. Alternatively, the conductive reflector may absorb the electromagnetic wave. You may make it use the rebar which is made of the metal of the reinforced concrete provided behind the board.

A finishing material such as an exterior tile may be arranged on the surface of the radio wave absorber. Strength can be improved by forming a recess in the back of the exterior tile, fitting a radio wave absorption plate into this recess, and integrating the radio wave absorption plate and the exterior tile together with concrete.

[0015]

1 is a sectional view of an embodiment of the present invention, and FIG. 2 is a front view of the embodiment. This radio wave absorbing outer wall panel 1 is used as a building exterior material, is manufactured in a factory, and therefore can improve the efficiency of construction work on site.
Further, it is possible to improve safety and further improve reliability of electromagnetic wave absorption performance. The outer wall panel 1 can be constructed by a conventional precast reinforced concrete assembly panel technique to create a building. A plurality of elongated radio wave absorption plates 2 are arranged side by side in the outermost layer (on the left side of FIG. 1) with a space, and behind them, a conductive reflector 3 common to these radio wave absorption plates 2 is arranged, Furthermore, it is integrally connected with concrete 6 together with the reinforcing bars 4 and 5 behind it. By arranging the electromagnetic wave absorbing plates 2 in parallel and at intervals, each of the electromagnetic wave absorbing plates 2 is made of concrete 6.
Therefore, it is possible to prevent peeling and peeling due to secular change. The radio wave absorption plate 2 is configured by mixing conductive fibers such as carbon fibers in a dielectric substance such as concrete and synthetic resin. As the carbon fibers contained in the radio wave absorber 2, various kinds of carbon fibers such as rayon-based, polyacrylonitrile (PAN) -based, phenol resin-based, coal pitch-based, petroleum pitch-based can be used. The content of this carbon fiber is 0.1 to 10 relative to the dielectric substance, for example, the hydraulic component (for example, cement) in the hydraulic composition (for example, mortar).
%, Preferably 0.1 to 6% by weight. If it is less than 0.1% by weight, the matching condition for radio waves is difficult,
On the other hand, if it exceeds 10% by weight, it becomes difficult to uniformly disperse the carbon fibers in the dielectric substance. Moreover, as the yarn length of the carbon fiber, one having an average yarn length of 0.3 to 5 mm in the molded body can be used.

The carbon fibers extend parallel to the electric field E of the radio wave to be absorbed, that is, in the direction perpendicular to the paper surface of FIG. 1 and in the left-right direction of FIG. In television broadcasting, this electric field E is horizontal, for example. The inventor of the present invention has sought to be able to efficiently absorb the incoming electromagnetic wave 7 by this. In orienting such conductive fibers, a mixture of a dielectric substance and conductive fibers can be extruded to manufacture.

The conductive reflector 3 has a large number of through holes, and may be, for example, a carbon fiber net, a metal net, or a metal punching metal. The thickness D1 between the surface 8 of the electromagnetic wave absorber 2 on the side where the electromagnetic wave 7 enters and the conductive reflector 3 is equal to the thickness of the concrete between the electromagnetic wave absorber 2 and the back surface 9 of the electromagnetic wave absorber 2 and the conductive reflector 3. By selecting the sum of the respective wavelengths of the electromagnetic waves inside 6 and 6 to be, for example, about 1/4, it is possible to cancel the incoming wave of the radio wave and the reflected wave of the conductive reflector 3 and prevent the reflection of the radio wave. The conductive reflector 3 may be placed in contact with the back surface 9 of the radio wave absorber 2. Since the conductive reflector 3 has a large number of through holes as described above, it is easy to pour the concrete 6 to manufacture the outer wall panel of the present case, and also the joints between the radio wave absorbers 2 are easily joined. The concrete 6 will be filled.

FIG. 3 is a sectional view of a radio wave absorbing outer wall panel 11 according to another embodiment of the present invention, and FIG. 4 is an outer wall panel 11 thereof.
FIG. This embodiment is similar to the previous one,
Corresponding parts are designated by the same reference numerals. It should be noted that the exterior tile 12 is used as the finishing material in this embodiment. The exterior tile has a recess 13 formed in the back, and the radio wave absorber 2 is fitted into the recess 13. The exterior tiles 12 are arranged in close contact with each other in the upper and lower sides of FIG. 3 and FIG. The radio wave absorber 2 and the exterior tile 12 are rebar 4,
5 and concrete 6 are integrally configured. The conductive reflector 3 has a large number of through holes as in the above-mentioned embodiments. In this way, the concrete 6 is tightly bonded to the radio wave absorber 2 and the exterior tile 12, whereby peeling of the exterior tile 12 can be prevented, and the fixing strength can be improved. The thickness D2 from the surface 14 of the exterior tile 12 to the conductive reflector 3 is selected to be, for example, 1/4 of the wavelength of the radio wave inside the same, as in the above-described embodiment. Stone or mortar may be used instead of the tile.

As another embodiment of the present invention, the conductive reflector 3 may be omitted in each of the embodiments shown in FIGS. 1 to 4, and the reinforcing bars 4 and 5 may serve to reflect electromagnetic waves.
This simplifies the configuration.

FIG. 5 is a sectional view of another embodiment of the present invention. This embodiment is similar to the embodiment of FIGS. 1 and 2 and corresponding parts bear the same reference numerals. In this embodiment, the radio wave absorber 2a is constructed by backing a conductive reflector 3a behind it, as shown in FIG. Radio wave absorber 2
a has the same structure as the above-mentioned radio wave absorption plate 2, and the conductive reflector 3a has the same structure as the above-mentioned conductive reflector 3. The radio wave absorber 2a and the conductive reflector 3a are integrally formed.

FIG. 7 is a sectional view of another embodiment of the present invention. This embodiment is similar to the embodiment of FIGS. 3 and 4, and corresponding parts bear the same reference numerals. Each wave absorber 2a
The conductive reflectors 3a are integrally lined with each other. The other structure is the same as that of the embodiment shown in FIGS.

[0022]

As described above, according to the present invention, a plurality of electromagnetic wave absorbing plates containing a dielectric substance and a conductive substance are arranged in the outermost layer or behind the finishing material and the conductive reflector is provided. Since the electromagnetic wave absorbing outer wall panel is configured by providing the above, it is possible to manufacture such an electromagnetic wave absorbing outer wall panel at the factory and use the conventional method of precast reinforced concrete assembly panel, which makes it possible to use high-rise buildings etc. The efficiency of the construction work can be improved, the safety can be improved, and the reliability of the electromagnetic wave absorption performance can be improved.

Further, according to the present invention, since the conductive fiber of the radio wave absorbing plate extends parallel to the electric field of the radio wave to be absorbed, the imaginary part of the complex permittivity is increased to improve the radio wave absorption,
Therefore, the thickness can be reduced. The thickness from the surface of the outer wall panel on the radio wave entrance side to the conductive reflector is selected to be, for example, about 1/4 of the wavelength of the radio wave inside each of them, whereby the incoming wave of the radio wave and the reflected wave of the conductive reflector are selected. It will be possible to offset the and and prevent the reflection of radio waves.

The conductive reflector is provided commonly to a plurality of radio wave absorbers, which facilitates manufacturing.
This conductive reflector has a large number of through holes, and concrete can be poured and fixed together with the radio wave absorbing plate, whereby the strength can be improved.

Further, according to the present invention, the structure can be simplified also by using the reinforcing bar of the reinforced concrete formed behind the radio wave absorber as the conductive reflector.

An exterior tile is used as a finishing material, and a radio wave absorber is fitted in a recess formed in the back of the exterior tile,
By integrating the radio wave absorber, the exterior tile, and the conductive reflector together with the concrete, it is possible to prevent the exterior tile from peeling off and improve the strength.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a radio wave absorbing outer wall panel 1 according to an embodiment of the present invention.

FIG. 2 is a front view of the radio wave absorbing outer wall panel 1 shown in FIG.

FIG. 3 is a radio wave absorbing outer wall panel 11 according to another embodiment of the present invention.
FIG.

4 is a front view of the radio wave absorbing outer wall panel 11 shown in FIG.

FIG. 5 is a sectional view of another embodiment of the present invention.

6 is a cross-sectional view showing a configuration in which a conductive reflector 3a is integrally lined with a radio wave absorbing plate 2a of the radio wave absorbing outer wall panel 1 shown in FIG.

FIG. 7 is a cross-sectional view of a radio wave absorption outer wall panel 11 of still another embodiment of the present invention.

[Explanation of symbols]

 1,11 Radio wave absorbing outer wall panel 2,2a Radio wave absorbing plate 3,3a Conductive reflector 4,5 Rebar 6 Concrete 7 Electromagnetic wave 12 Exterior tile

Claims (4)

[Claims] 1. A plurality of radio wave absorbing plates are arranged side by side in the outermost layer or behind a finishing material, each radio wave absorbing plate containing a dielectric substance and a conductive fiber, and the conductive fiber is An electromagnetic wave absorbing outer wall panel, which extends in parallel to an electric field of a radio wave to be absorbed, and behind or behind a plurality of electromagnetic wave absorbing plates, a conductive reflector common to these electromagnetic wave absorbing plates is arranged or lined. 2. The electromagnetic wave absorbing outer wall panel according to claim 1, wherein the conductive reflector has a large number of through holes, and concrete is poured and fixed together with the electromagnetic wave absorbing plate. 3. The electromagnetic wave absorbing outer wall panel according to claim 1, wherein the conductive reflector is a reinforcing bar of reinforced concrete provided behind the electromagnetic wave absorbing plate. 4. The finishing material is an exterior tile, and a radio wave absorber is fitted into a recess formed behind the exterior tile,
The radio wave absorbing outer wall panel according to claim 1, wherein the radio wave absorbing plate and the exterior tile are integrally formed with concrete.