JP2535685B2 - Mesh material for antenna reflector - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna reflecting mirror surface mesh material used for forming a reflecting mirror surface of a mirror antenna mounted on, for example, an artificial satellite.

[0002]

2. Description of the Related Art As is well known, as a means for improving the characteristics of a mirror-surface antenna, it is essential to increase the diameter of the antenna reflection mirror surface and to improve the shape accuracy. As a method for obtaining such a large-diameter and high-precision mirror surface precision, it is advantageous to form an antenna reflecting mirror surface using a mesh material having high flexibility and elasticity. The antenna reflector using this mesh material can be easily transported and installed to tall buildings and mountainous remote areas because the supporting structure can be made smaller, and rainwater and snowmelt water can be reflected from the reflector surface. It has the advantage that drainage is easy. When such a mirror surface antenna is constructed in outer space, the antenna reflection mirror surface can be easily folded and unfolded, so that there is an advantage that it is easy to secure a launch fairing space.

FIG. 3 shows such a mirror antenna, in which a mesh material is spread through a support structure (not shown) to form a mesh mirror surface 1, and a power feeding section 2 feeds power on the mesh mirror surface 1. The support members 3 are arranged to face each other.

Since a highly accurate mirror surface precision is required as the mesh material used for the antenna reflecting mirror surface of such a mirror surface antenna, it is stretched to a desired mirror surface precision in a state where the support structure is assembled. Since it is set, it is formed of a conductive fiber that has high strength, is rich in flexibility and elasticity, and has desired electrical characteristics. The conductive fiber is also required to have small thermal expansion, corrosion resistance, and weather resistance so that it can be used in harsh environments including space environment.

[0005] Further, in the case of construction in outer space, it is necessary to fold as small as possible before transporting to outer space, and then, when reaching the outer space, unfold and secure the desired mirror surface accuracy set on the ground. Is required.

By the way, as such a conventional mesh material, US Pat. No. 4,609,923, US Pat.
te of Patent: Sep. 2, 1986) using a gold-plated molybdenum wire or a tungsten wire. Since the conductive material of the molybdenum wire or the tungsten wire, which is the base line, is easily oxidized in this mesh material, it is woven into a mesh shape after being subjected to a gold plating treatment (see FIG. 3). (See) is formed.

However, the above mesh material has a problem that pinholes and hydrogen gas, which are inevitable in the plating process, remain in the plating layer, and the bulk gold lowers the mechanical strength, resulting in brittleness. According to this, the conductive fibers themselves react through the pinholes, and the mechanical strength of the coating is reduced, and the fibers rub against each other due to vibrations such as wind and rain during the mirror surface adjustment of the mesh mirror surface and after installation. There is a risk of scratching, peeling of the coating, or corrosion due to erosion such as wind and rain. This is a serious problem especially in the field of space development, which is difficult to maintain and check.

Therefore, increasing the thickness of the gold plating layer can be considered as a means for removing pinholes and residual hydrogen gas. However, according to this, since the weight of the material itself increases and the rigidity thereof decreases, it becomes difficult to achieve the required weight reduction, high strength, and high rigidity in the field of space development.

Further, in the above-mentioned plating treatment, the solution after the plating treatment is drained from the viewpoint of environmental pollution,
There was also a problem that the manufacturing work including the wastewater treatment was very troublesome.

[0010]

As described above, in the conventional mesh material for antenna reflecting mirrors, when the gold plating layer is made thin, the coating is damaged or peeled off due to the friction between the fibers, resulting in corrosion resistance. When the thickness and the thickness of the plating layer are increased, the weight and the rigidity of the plated layer are reduced.

The present invention has been made in view of the above circumstances, and it is possible to promote high strength and high rigidity without making a plating treatment, and to have high corrosion resistance and weather resistance. An object of the present invention is to provide a mesh material for an antenna reflecting mirror surface, which can be improved in performance.

[0012]

According to the present invention, there is provided a mesh material for an antenna reflecting mirror surface, wherein conductive fibers are woven in a mesh shape to form a mesh mirror surface. At least the surface of the conductive fibers is coated with titanium carbide or titanium nitride. It is configured to cover.

[0013]

According to the above structure, the titanium carbide or titanium nitride coating has excellent electrical conductivity, is lighter than the gold-plated layer, and has robust characteristics. Along with mutual wear and corrosion resistance,
It is lightweight and promotes high strength and high rigidity.

[0014]

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

FIG. 1 shows a mesh material for an antenna reflecting mirror surface according to an embodiment of the present invention, which is a conductive fiber 10 constituting the mesh mirror surface 1. That is, the conductive fibers 10 are formed on the surface of the fibers 10a made of a molybdenum metal alloy having a wire diameter of 20 μm, for example, by a plasma CVD, a thermal CVD, or the like to form titanium carbide (Ti
C) or titanium nitride (Ti N) coating 10b is applied. Of these, titanium carbide has an electric conductivity of about 5 Ms / m, a hardness of H _v = 2000, and a density of 4.9 g / m.
It is cc. On the other hand, titanium nitride has an electric conductivity of about 2 Ms / m, a hardness of H _v = 3000, and a density of 4.4.
It is g / cc.

A plurality of, for example, four conductive fibers 10 are twisted (twisting frequency: 1 time / 25 mm) to form a fiber bundle, and the fiber bundle is, for example, 2 mm × 2 mm by using a tricot knitting machine. 2 is manufactured by being woven into the mesh shape of FIG.
However, the mesh mirror surface 1 (see FIG. 3) is formed by cutting into a desired shape such as a diameter of 2.5 m.

As an evaluation test of the above mesh material, a test piece in which the mesh 11 was cut into, for example, 25 mm × 25 mm and attached to a plate was brought into contact with a load load of 1 kg to perform a friction test with a friction sliding distance of 10 km. Then, a salt spray test was conducted to evaluate the corrosion resistance.

Further, as an evaluation of corrosiveness by an erosion test, sic powder having an average diameter of 40 μm was applied to the same test piece, and 4 kg / cm ² was used as a carrier gas. The electrically conductive fiber was vertically placed 10 mm backward with the compressed air of, and this state was held for 100 hours. Further, as the electrical characteristic test, measurements were performed in reflectance 14GH _z zone.

As the test pieces used in these tests, a titanium carbide coating 10b is formed on the surface of the fiber, which is a feature of the present invention.
The test piece A using the conductive fiber having the above-mentioned structure and the test piece B having the titanium nitride film 10b formed on the surface of the fiber were used, and the results are shown in Table 1. Then, in order to compare with the evaluation results of these test pieces A and B, a conductive fiber obtained by forming a 0.5 μm gold-plated layer on a fiber made of a molybdenum metal alloy having a wire diameter of 20 μm by an electroplating method as in the conventional case 4 fibers (twisting frequency: 1 time / 25 mm) are twisted to form a fiber bundle, and the fiber bundle is 2 mm × 2 by a tricot knitting machine.
25mm x 25mm mesh woven into a mesh
A test piece C cut into mm was similarly tested. As a result,
As shown in Table 1, the test pieces A and B according to the present invention ensure the same reflectance as the test piece C having the conventional gold-plated layer, and the corrosion resistance after the friction test and the corrosion resistance after the erosion test. It is confirmed that they are excellent and do not corrode. Also in terms of weight, the test piece A according to the present invention
It is confirmed that B and B are lighter than the conventional test piece C.

[0020]

[Table 1]

As described above, the antenna reflecting mirror surface mesh material is coated with the titanium carbide or titanium nitride coating 10b so as to cover the surface of the fiber 10a, and the coating 10b.
The conductive fiber 10 adhered to was woven into a mesh shape to form the mesh mirror surface 1. According to this, the coating film 10b adheres to the fibers 10a to promote abrasion resistance and corrosion resistance between the fibers. Further, this coating is lighter in weight than the conventional gold-plated layer and has robust characteristics, so that it is light in weight, promotes high strength and high rigidity, and secures excellent electrical conductivity. Further, according to this, since it is possible to prevent environmental pollution by eliminating the plating process, the manufacturability can be simplified.

Although the conductive fiber 10 is made of molybdenum metal alloy in the above-mentioned embodiment, the present invention is not limited to this, and metal alloy wire such as tungsten, piano, stainless steel, niobium wire, carbon fiber, or sic. Fiber, B fiber, si3N
It is also possible to use inorganic fibers such as 4 fibers, BN fibers, Al203 fibers and sio2 fibers, and polymer fibers such as aramid fibers and polyimide fibers. Therefore, it goes without saying that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

[0023]

As described above in detail, according to the present invention, it is possible to reduce the weight and promote high strength and high rigidity without performing the plating treatment, and to improve the corrosion resistance and the weather resistance. It is possible to provide a mesh material for an antenna reflecting mirror surface, which can achieve high performance.

[Brief description of drawings]

FIG. 1 is an enlarged view showing a mesh material for an antenna reflecting mirror surface according to an embodiment of the present invention.

FIG. 2 is a diagram showing the conductive fiber of FIG. 1 taken out.

FIG. 3 is a diagram showing a mirror antenna to which the present invention is applied.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Antenna reflecting mirror surface, 2 ... Feed part, 3 ... Feed part support member, 10 ... Conductive fiber, 10a ... Fiber, 10b ... Coating,
11 ... Mesh.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Tatsuyoshi Aisaka 1 Komukai Toshiba Town, Komukai-cho, Kawasaki City, Kanagawa Prefecture Komu Plant, Toshiba Corporation (72) Koichi Furukawa Toshiba Komukai Toshiba, Kawasaki City, Kanagawa Prefecture No. 1 in the town Inside the Toshiba Komukai factory (72) Inventor Yuji Tsutsumi No. 1 Komukai Toshiba town, Komukai-ku, Kawasaki-shi, Kanagawa Inside the Toshiba Komukai factory

Claims (1)

(57) [Claims] 1. A mesh material for an antenna reflecting mirror surface, wherein conductive fibers are woven into a mesh shape to form a mesh mirror surface, wherein at least the surface of the conductive fibers is coated with a film of titanium carbide or titanium nitride. Mesh material for antenna reflector.