JPH027199B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a ferrite member for absorbing radio waves in a radio wave absorbing wall.

(Prior Art) Conventionally, a tile-shaped ferrite board a has been used as a radio wave absorber in a building's radio wave absorbing wall, and the ferrite board a is attached to a concrete frame b as shown in Fig. 12.
The ferrite plate a is fixed via a holding metal fitting c that holds it and a holding metal fitting d that fixes the metal fitting c to the body b, or via a metal holding jig e as shown in Fig. 13. and is fixed via an anchor bolt f as shown in FIG.

Alternatively, as shown in FIG. 15, a ferrite plate a may be adhered to a metal plate g or a reflective plate layered on a concrete body b via an adhesive b, or a first
As shown in Figure 6, a metal reflective leg piece i attached to a ferrite plate a is glued to a concrete frame.

(Problem to be Solved by the Invention) However, fixing a tile-shaped ferrite plate to a concrete frame using holding hardware, presser metal fittings, anchor bolts, etc. is a problem in that a radio wave reflecting object is placed on the front of the ferrite board, which is a radio wave absorber. A certain metal surface protrudes and impedes the radio wave absorption performance of ferrite.

Also, when fixed to a metal plate etc. using adhesive,
There is a risk of peeling due to differences in thermal expansion coefficients,
There are also problems with heat resistance and water resistance.

(Means for solving the problems) The present invention relates to a modified ferrite member for radio wave absorption proposed to solve the above problems,
A ferrite member for absorbing radio waves in a radio wave absorbing wall that solves the above problems by being molded to have an irregular cross section, an uneven surface, or a rough surface so as to increase the adhesion area with concrete. It is.

(Function) The ferrite member according to the present invention is installed in a concrete frame, and in this case, the member is molded to have an uneven surface or a rough surface,
Alternatively, since it is molded to have an irregular cross section, the adhesion area to the concrete is increased, and it is firmly fixed to the concrete frame without using any special support or fixing material, and exhibits radio wave absorption performance.

(Example) The present invention will be described below with reference to the illustrated embodiments.

In the embodiment shown in FIGS. 1 to 3, A is a tile-shaped ferrite member, on the back surface of which grooves 1 and convex ridges 2 with a dovetail cross section are alternately provided, and each of the grooves The surfaces of the ridges 1 and 2 are roughened to increase the area of contact with concrete.

The ferrite member A is implanted in a predetermined position within the concrete wall B, and functions as a radio wave absorbing material.

At this time, the ferrite member A can be used without using special supporting materials or fixing materials due to the grooves 1 and ridges 2 provided on its back surface, as well as the rough surface portions formed on these surfaces. , firmly anchored to the concrete part.

In the figure, 3 is a surface finishing material applied by spraying or other methods, and 4 is a metal reflective material.

4 and 5 show another embodiment of the present invention, in which a protruding strip 5 with a T-shaped cross section is provided protruding from the center of the back surface of the flat body of the ferrite member A in the longitudinal direction. The strips 5 increase the adhesion to concrete, and the protruding strips 5 also serve as spacers for positioning the main body of the ferrite member A, increasing construction accuracy. Furthermore, by forming a long molded body, the void in the direction of the magnetic field is minimized and the radio wave absorption performance is improved. FIG. 5 shows the state in which the ferrite member A is used, and in the figure, parts equivalent to those of the embodiment described above are given the same reference numerals.

Note that the protrusions 5 may be arranged at predetermined intervals as shown in FIG.

FIG. 7 shows another embodiment of the present invention, in which the ferrite member A is a bar-shaped material in the shape of a deformed reinforcing bar, and the adhesion force to concrete is increased by the ridges 6 protruding from the outer periphery of the bar-shaped body. It is something.

As shown in FIG. 8, the ferrite member A is
Like reinforcing bars, they are arranged in a mesh in the vertical and horizontal directions to obtain the required electric field porosity, and because they are long rods, they can be constructed so that the magnetic field porosity is almost zero.

In the drawings, parts equivalent to those of the above embodiments are given the same reference numerals.

FIG. 9 shows still another embodiment of the present invention, in which the ferrite member A is formed to have a square cross section and is formed so as to increase its adhesion to concrete, and the bent pieces 7 on both sides are attached to a metal reflecting plate on the back side. It is installed in concrete wall B so as to face 4. (See FIG. 10) In addition, as shown in FIG. 11, the ferrite member A may have both rising pieces 8 and bent pieces 7 cut out in the middle portion thereof.

(Effects of the Invention) As described above, the irregularly shaped ferrite member for absorbing radio waves according to the present invention has an increased adhesion force to concrete because the member itself is molded into an irregular cross section or has an uneven surface or a rough surface. However, it is firmly buried in the concrete structure without using special supports or fixing materials, which simplifies construction and prevents radio wave absorption performance from being hindered by supports and fixing materials as in the past. Moreover, by embedding the ferrite member of the present invention in a concrete wall body, the range of selection of surface finishing materials increases, and it can be adapted to various designs.

Further, as described above, the electromagnetic wave absorbing deformed ferrite member according to the present invention is formed to be elongated in the direction of the magnetic field, thereby improving its electromagnetic wave absorption performance.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of the irregularly shaped ferrite member for absorbing radio waves according to the present invention, FIG. 2 is a side view thereof, and FIG. 3 is a longitudinal cross-sectional view showing its usage state.
FIG. 4 is a perspective view showing another embodiment of the present invention, and FIG.
The figure is a vertical cross-sectional view showing its use, FIG. 6 is a perspective view showing another embodiment of the present invention, FIG. 7 is a perspective view showing still another embodiment of the invention, and FIG. 8 is a perspective view showing its use. 9 is a perspective view showing another embodiment of the present invention, FIG. 10 is a longitudinal sectional view showing its usage state, and FIG. 11 is a further embodiment of the present invention. 12 to 15 respectively show a state in which a conventional ferrite member is attached to a concrete wall, FIGS. 12, 13, and 15 are respectively slope views, and FIG. 14 is a cross-sectional plan view thereof. 16th
The figure is a perspective view of a conventional ferrite member. A... Ferrite member, B... Concrete wall, 1... Concave groove, 2... Convex ridge, 5... Protruding ridge, 6... Protruding ridge, 7... Bent piece, 8... Rising pieces on both sides.

Claims (1)

[Claims] 1. A ferrite member for radio wave absorption in a radio wave absorption wall, characterized by being formed to have an irregular cross section, an uneven surface, or a rough surface part so as to increase the adhesion area with concrete, and to be elongated in the direction of the magnetic field. A deformed ferrite member for absorbing radio waves.