JPH02252302A - Reflector for parabolic antenna and manufacture of reflector - Google Patents

Abstract

PURPOSE:To simplify the manufacture process by forming a reflection plate with mold forming and adhering incorporatedly the reflecting plate and a reflection film with a reaction heat of a forming material at molding. CONSTITUTION:A metallic die 5 of a forming machine is separated into a lower metallic die 51 and an upper metallic die 52, a nearly spheric or parabolic curved face 54 is provided to the lower metallic die 51 and a curved face 57 nearly equal to the curved face 54 of the lower metallic die 51 is provided to the upper metallic die 52 at a prescribed interval. A release agent 4 is coated to the lower metallic die 51 and a paint being the mixture of urethane resin colored in advance and aluminum powder is painted to form the reflecting film 3. Then the upper metallic die 52 is fitted to the lower metallic die 51 and a forming material made of a foamed urethane resin is injected to the reflecting film 3 from a gate 53 to form the reflecting plate 2. The reflecting film 3 is cross-linked and cured the reaction heat of a forming material, bonded and incorporated with the reflecting plate 2 and the manufacture of the reflector 1 is finished.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a reflector for a parabolic antenna and a method for manufacturing the reflector.

[Conventional technology]

As shown in FIG. 5, the reflector for a parabolic antenna includes a reflector 6 made of FRP (glass fiber reinforced plastic) and having a substantially spherical or parabolic cross section and a substantially circular or elliptical plane, and a surface of the reflector 6. A reflective layer 7 made of aluminum foil or the like is provided on the reflective plate 6 and is integrally adhesively formed with the reflective plate 6.
A protective film 8 of paint is formed on the surface of the protective film 8. By the way, there are various methods for molding FRP, but for the reflector, SMC
(sheet molding compound) method is often used. This SMC method involves cutting and laminating sheets of molding material mixed with glass-woven polyester resin, fillers, etc. and aluminum foil, etc., and then hardening this under pressure in heated male and female molds. Expensive materials and 120 to 150 degrees
There were disadvantages in that it required repeated heating of the mold and a molding time of 5 minutes or more, and that the protective film 8 had to be coated in a separate process after molding.

[Problem to be solved by the invention]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional drawbacks and to provide a reflector for a parabolic antenna and a method for manufacturing the reflector that is inexpensive and easy to manufacture.

[Means to solve the problem]

In order to solve the above problems, the present invention provides a reflector for a parabolic antenna comprising a substantially spherical or parabolic reflecting plate and an electromagnetic wave reflecting film covering the surface of the reflecting plate,
The reflective plate was formed by molding, and the reflective plate and the reflective film were integrally bonded together using the reaction heat of the molding material during molding. A urethane resin was used as the molding material, a pre-colored urethane resin was used as the reflective film, and a resin mixed with an electromagnetic wave reflective material was used as the reflective film.

Then, an electromagnetic wave reflecting film is formed by painting on the approximately spherical or parabolic part formed in the mold for molding,
A manufacturing method was adopted in which a molding material was injected through the reflective crotch, and the reflective film was cured together with the reflective plate by the reaction heat of the molding material.

[Effect]

According to the above configuration, the reflecting plate is formed into a predetermined shape by a molding material injected into a molding die formed into a substantially spherical or parabolic shape, and is coated on the molding die. The reflective film formed is crosslinked and cured by the reaction heat of the molding material, and is bonded and integrated with the reflective plate.

〔Example〕

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

1 is a reflector for a parabolic antenna, and this reflector 1 is made of foamed urethane resin and is molded to include a reflecting plate 2 whose cross section is approximately spherical or parabolic and whose plane is approximately the same or elliptical, and which covers the surface of the reflecting plate 2. The reflective plate 2 is integrally bonded with a reflective film 3 made of a colored urethane resin mixed with aluminum powder as an electromagnetic wave reflective material. Next, a method for manufacturing the reflector 1 will be described in the following, in which the electromagnetic wave reflecting material includes powders of other metals, carbon, etc., fibers, and the like can be used in addition to the aluminum powder.

5 is a mold of a mold forming machine, and this mold 5 is a lower mold 51.
and an upper mold 52. Then, the lower mold 51
has an apex above and a cross section that is approximately spherical or parabolic;
A curved surface 54 whose plane is approximately the same or elliptical, and the same curved surface 5
A through hole 55 for cooling or heating is provided in the lower part of No. 4, and the lower end 56 of the peripheral edge of the curved surface 54 is formed into a curved surface to improve moldability. On the other hand, the upper mold 52 is provided with a curved surface 57 such as a groove between the curved surface 54 of the lower mold 51 and a predetermined distance from the curved surface 54 of the lower mold 51, and a peripheral lower end 58 of the curved surface 57. is formed into a curved surface to improve moldability, and the upper part of the curved surface 57 has a through hole 55 for cooling or auxiliary heating, and around the curved surface 57, an injection port 53 for molding material and an air vent 59 are provided. have.

Further, a wide cross-section of the fitting portion of the lower mold 51 and the upper mold 52 forms a crank-shaped stepped portion 60.

Then, apply a thin layer of mold release agent 4 to the lower mold 51 of the mold forming machine.
The reflective film 3 is formed by applying a paint mixture of pre-colored urethane resin and aluminum powder to a thickness of about 100 microns. Then, the upper mold 52 is fitted into the lower mold 51, and a foamed urethane resin molding material is injected onto the reflective film 3 through the injection port 53, thereby forming the reflective plate 2 into a predetermined shape. Then, the reflector 113 formed by painting on the lower mold 51 is cross-linked and hardened by the reaction heat of the molding material, and is adhesively fixed to the reflector 2 to complete the manufacture of the reflector 1.

Furthermore, in the case of a satellite broadcasting antenna using the above-mentioned reflector, it is possible to easily create a structure in which the reflector and the installation leg are integrally molded by changing the shapes of the upper and lower molds.

〔Effect of the invention〕

As described above, according to the present invention, the manufacturing process of the reflector can be carried out in the same mold, so it is possible to save space in the workplace, and it is also possible to save time in a short time by using inexpensive materials and without the need for external heating. Since it can be made into

Furthermore, the lighter weight also reduces the burden of transportation and installation.

[Brief explanation of drawings]

Fig. 1 is an external view of a reflector for a parabolic antenna showing an embodiment of the present invention, Fig. 2 is a side sectional view of the same main part, and Fig. 3 is a side sectional view of a mold for explaining the manufacturing method of the reflector. 4 are side sectional views for explaining the manufacturing method using the same mold, and FIG. 5 is a side sectional view of the main part of the conventional example. DESCRIPTION OF SYMBOLS 1...Reflector, 2...Reflection plate, 3...Reflection film, 5...Mold. Patent applicant: Fujitsu General Ltd. Figure 1 Figure 3

Claims (5)

[Claims] (1) A reflector for a parabolic antenna consisting of a substantially spherical or parabolic reflecting plate and an electromagnetic wave reflecting film covering the surface of the reflecting plate, in which the reflecting plate is formed by molding, and the reflecting plate and . A reflector for a parabolic antenna, characterized in that the reflective film and the reflective film are integrally bonded together by reaction heat of a molding material during molding. (2) The reflector for a parabolic antenna according to claim (1), wherein the molding material is a urethane resin. (3) The reflector for a parabolic antenna according to claim (1), wherein the reflective film is made of a pre-colored urethane resin. (4) The reflector for a parabolic antenna according to claims (1) and (3), wherein the reflective film is a resin mixed with an electromagnetic wave reflective material. (5) Form a reflective film for electromagnetic waves by painting on the approximately spherical or parabolic part formed in the molding die, inject the molding material onto the reflective film, and use the reaction heat of the molding material to create a reflective plate. A method for manufacturing a reflector, characterized in that the reflective film is also cured.