JPS6389803A - Reflecting mirror made of fiber reinforced plastic - Google Patents

Abstract

PURPOSE:To obtain a reflecting mirror which is free from nonuniform molding strain and thermal deformation, is reduced in weight and has high accuracy by using a carbon fiber reinforced plastic (CFRP) sheet which has uniform quality, isotropic mechanical and thermal characteristics, coefft. of thermal expansion smaller than the coefft. of thermal expansion of a high-polymer foam and a low density as a core material after working said sheet to a currugated fiberboard shape. CONSTITUTION:The fiber reinforced plastic (FRP) sheets 2 are adhered to both faces of the core material 8 by an adhesive agent 3. A reflection film 4 is formed by vapor deposition, etc., on the surface to be formed as the reflection surface of the FRP sheet 2. Rays of an IR to UV region are reflected by the reflecting mirror constituted in the above-mentioned manner. The core material 8 consists of a currugated sheet 9 formed by folding the CFRP sheet having 0.03-1.0g/cm<3> density and uniform quality to the corrugated shape and the flat CFRP sheet 10 adhered thereto. Since this reflecting mirror consists of the core material 8 having the isotropic mechanical and thermal characteristics, the generation of the nonuniform molding strain and thermal deformation is obviated. The core material 8 can be made to have about <=1X10<-5> deg.C coefft. of thermal expansion by which the reflecting mirror having the excellent thermal dimension stability, lightweightness, high rigidity and high accuracy is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a reflective mirror made of fiber-reinforced plastic, particularly to a reflective mirror that reflects light in the infrared to ultraviolet range.

[Conventional technology]

Figures 4 and 5 are cross-sectional views of another conventional optical mirror made of fiber reinforced plastic (hereinafter referred to as FRP). In Figure 2, (1) is a core material made of a honeycomb core or polymer foam; 2) is an adhesive (
3) A bonded FRP board, for example, a carbon fiber reinforced plastic (hereinafter referred to as CFF1a) board.

(4) is a reflective film formed by vapor deposition or the like on the surface of the FRP board (2) that will become a reflective surface, (5) is a support that supports the reflection vl, and (6) is an FRP plate that does not become a reflective surface ( 2) is a reflecting mirror support body which is attached to a support body (5). In Figure 4, 2
A hard and smooth base layer such as glass or metal is applied to the surface of the FRP board (2), which becomes the reflective surface (9 reflective film (4)
is applied to its surface.

In the FRP reflector configured as above, F
The reflective film (4) provided on the surface of the RP board (2) reflects light in the infrared to ultraviolet range.

[Problem that the invention seeks to solve]

Since the conventional pRpg reflector is configured as described above, when the core material (1) is a honeycomb core, the mechanical
Since the thermal properties are not isotropic, 2, for example, molding distortion and thermal deformation occur. Even if the honeycomb core is divided and arranged in consideration of directionality, anisotropy remains within the two divided cores, and uneven molding distortion and thermal deformation cannot be completely eliminated.

Furthermore, when the core is divided, the mirror surface is deformed due to the discontinuity of the core divided portion. As a result, when the light beam is reflected and imaged, the image becomes blurred, and even when the light beam emitted from the light source at the focus of the two reflecting mirrors is reflected, it does not become a parallel light beam with a uniform intensity distribution. .

On the other hand, if the core material (11) is a homogeneous polymer foam, non-uniform deformation will not occur, but the coefficient of linear expansion will be 3 to 7 x 10'/
℃, the thermal deformation is generally large, as in the case of an aluminum honeycomb core, for example. Furthermore, when considering the stiffness versus weight as a sand inch board.

Polymer foams had problems such as being inferior to those with honeycomb cores as core materials (11).

This invention was made to solve the above-mentioned problems, and provides a PRP reverse reflector that is free from uneven molding distortion and thermal deformation, is lightweight, has high rigidity, and has excellent thermal dimensional stability. The purpose is to

[Means for solving problems]

The core material of the FRP reverse reflector according to this invention has a density of +
103-1. op/cII? A corrugated core material consisting of a corrugated plate made by bending a homogeneous CFRP (carbon fiber reinforced plastic) plate into a corrugated shape and a flat plate of CFRP attached to this corrugated plate is used, and FRP plates are fixed to both sides of the corrugated core material. However, a reflective film is formed on the surface of this FRP board that becomes the reflective surface.

[Effect]

The FRP counter-reflector core material in this invention is made of a low-density CFRP plate processed into a cardboard shape, which is homogeneous, has isotropic mechanical and thermal properties, and has a linear expansion coefficient smaller than that of polymer foam. As a result, there is no uneven molding distortion or thermal deformation.
A lightweight, high-precision four-reflector can be obtained.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

Figures 1 and 2 are sectional views showing other embodiments of the present invention.
The same or corresponding parts as in FIG. 5 and FIG. 5 are shown. The basic structure of these FRP counter-reflectors is similar to the conventional FRP counter-reflector shown in FIGS. 4 and 5.

Further, in FIG. 3, (8) is the core material of the reflecting mirror according to the present invention, and has a density of 0.03 to L 01/ar? The corrugated plate (9) is made by bending a homogeneous CFRP plate into a corrugated shape, and the CFRP flat plate a is attached to the corrugated plate (9). FRP boards (2), such as CFRP boards, are bonded to both sides of this core material (8) with an adhesive (3).

Furthermore, in the embodiment shown in FIG. 1, a υ reflection film (4) is formed by vapor deposition or the like on the surface of the concave FRP plate (2) where reflection rfi<mirror surface. Further, in the embodiment shown in FIG. 2, a hard and smooth base layer (7) is provided on the surface of the FRP board (2) on the concave side, that is, the reflective surface side, and this base layer (7)
A reflective film (4) is formed on the surface by vapor deposition or the like.

The base layer (7) may be made of glass, for example.

Metal etc. are used.

In the FRP counter-reflector configured as described above, since the core material (8) has isotropic mechanical and thermal properties, uneven molding distortion and thermal deformation do not occur. Furthermore, since the linear expansion coefficient of the core material (8) can be made 1×10° C. or less, it has excellent thermal dimensional stability.

A lightweight, highly rigid, and highly accurate reflector can be obtained.

In addition, although the above embodiment shows a reflecting mirror having a curved shape as a whole with a concave surface serving as a light reflecting surface, the present invention can also be applied to a reflecting mirror having two convex reflecting surfaces or a flat reflecting mirror. . Furthermore, a similar effect can be obtained by using a core material formed into a cardboard shape by attaching flat plates σQ to both sides of the corrugated plate (9).

〔Effect of the invention〕

As described above, according to the present invention, the core material of the two-reflector has a density of 0.03 to 1.0 g/clr? homogeneous CFR
Since we use a cardboard-like core material consisting of a corrugated P plate bent into a corrugated shape and a flat CFRP plate attached to this corrugated plate, there is no uneven molding distortion or thermal deformation, and it is lightweight and rigid. An FRPfi reflecting mirror with high thermal stability and excellent thermal dimensional stability can be obtained.

[Brief explanation of the drawing]

1 and 2 are respectively a sectional view of an FRP anti-reverse mirror according to another embodiment of the present invention, and FIG. 3 is a perspective view showing a core material used in another embodiment of the present invention. 4 and 5 are cross-sectional views of other conventional FRP reverse reflecting mirrors, respectively. In the valley diagram, the same symbol indicates the same or equivalent part. (1), (8) are core materials, (2) is FRP board, (3) is adhesive, (4) is reflective film, (7) is base layer, (9) is corrugated board, α1 is CFRP It is a flat plate.

Claims (3)

[Claims] (1) Homogeneous C with a density of 0.03 to 1.0 g/cm^3
A cardboard-shaped core material consisting of a corrugated FRP board bent into a wave shape and a CFRP flat plate attached to this corrugated board, fiber-reinforced plastic plates fixed to both sides of this core material, and this fiber-reinforced plastic. A reflective mirror made of fiber-reinforced plastic, characterized by comprising a reflective film formed on a surface of a plate that serves as a reflective surface. (2) The fiber-reinforced plastic reflective mirror according to claim 1, further comprising a hard and smooth base layer between the reflective film and the fiber-reinforced plastic plate. (3) The fiber-reinforced plastic reflecting mirror according to claim 2, wherein the base layer is glass or metal.