JP3225339B2 - Radome for antenna and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radome for an antenna of a terrestrial microwave communication parabolic antenna, and more particularly to a strong and lightweight antenna radome which transmits electromagnetic waves well, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, a parabolic antenna has been used for terrestrial microwave communication. However, if rain or snow is attached or snow is present, the communication performance is reduced. Becomes It is sufficient to simply cover the roof, but in the case of fixing to a tall tower, it is preferable to cover the antenna directly with a coating called radome.

[0003]

Since a large parabolic antenna having a diameter of more than 2 m is used, a radome for a large antenna needs to have a diameter of more than 3 m. When such a radome is formed in a substantially shade-like body such as, for example, an Ajiro shade, a synthetic resin material such as FRP
When the thickness is 5 mm to 12 mm, there is a problem in transmission of communication microwaves. If the thickness of the FRP plate is reduced, there is a problem in terms of rigidity.
Although rigidity can be improved by sandwiching a urethane resin or the like between the two P plates, there is a problem that the manufacturing process is complicated and the cost is high. In view of these circumstances, the present invention provides an antenna radome that satisfies conditions such as good transmission of radio waves, light weight, excellent rigidity and durability, easy manufacturing and low cost burden. It has been developed for the purpose of providing a manufacturing method thereof.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a hollow double-walled structure in which a hollow portion between the front and back FRP plates and the front and back FRP plates is connected and supported by countless thin columns. An antenna radome having a substantially hat-shaped structure comprising a main body having a structure and an FRP flange formed at a peripheral edge of the main body, wherein the main body has a double cloth of a pair of opposing fibers. The front and back FRP plate formed by filling each with a synthetic resin filler, and the synthetic resin filler filled in the double cloth of the above-mentioned fibers are impregnated into the binding yarn fiber bundle connecting the double cloth, and each of the bonding is performed. Technical measures are taken to consist of a thin strut formed by hardening the yarn upright. In the invention according to claim 2, the antenna radome comprising the main body and the flange comprises a combination of several sections divided by a plurality of radiations passing through the center thereof, and the arc of each section is formed. A technical measure is taken such that a flange made of a single plate of FRP is formed at the curved edge portion, and an FRP flange for segmented body joining is projected from the isosceles side end to the concave surface side.

According to a third aspect of the present invention, there is provided a method of manufacturing a radome for an antenna, wherein a step of forming a coating film layer on a concave surface of a mold for forming a substantially cap-shaped structure, if necessary, Laying a heavy cloth and filling with a synthetic resin filler, impregnating the filler into the binding yarn fiber bundle of the double cloth and curing it upright; The technical means of combining a step of forming a flange by laminating a material and a fiber and a step of forming a bolt hole at predetermined intervals in the flange are taken.

[0006]

The present invention configured as described above has the following functions. (1) Since the shape is a substantially shade-like structure such as an Ajiro shade, rain and snow can be prevented by disposing it on the upper or front surface of the parabolic antenna. Further, the area for receiving wind is reduced. (2) Since the flange is provided on the outer peripheral edge, it can be easily fixed to the fixed object via the support member. (3) Since the central part of the substantially cap-shaped structure is hollow with a double structure, the front and back FRP plate materials are thin and easily transmit radio waves, and the narrow struts in the hollow part are also arranged thinly and roughly. In order to transmit radio waves per se, the loss of radio wave transmission is reduced as compared with the case where FRP is filled with the same thickness. (4) The narrow struts are formed by impregnating a synthetic resin filler into a fiber bundle having a length of, for example, 3 to 10 mm, and being hardened. The compression strength in the longitudinal direction is excellent,
Since the P plate is integrally connected and supported by the thin struts, the P plate has excellent rigidity and strength, and since the weight is lighter than the apparent volume, the strength of the support member can be reduced even when installed at a high place. (5) A substantially shade-shaped structure composed of a combination of a plurality of divided bodies is:
A large one having an overall diameter of 3 to 4 m or the like can be easily manufactured, and the joining flange on the concave side increases the overall strength.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a radome for an antenna and a method of manufacturing the same according to the present invention will be described below with reference to the drawings. FIG. 1 shows a first example of an antenna radome 1.
It is a partial vertical side view which shows an Example. The antenna radome 1 is, for example, a circle having a plane diameter of 50 to 300 cm, and is formed in a substantially conical shape with a raised central portion, and in a substantially hat-like shape such as a net-shaped cap on the side surface. The substantially cap-shaped structure 2 is formed with a flange 3 at the peripheral edge, and the main body is formed as a hollow double part 4 by front and back FRP plates 9 and 11.

As shown in detail in FIG. 2, the flange 3 is provided with a coating film layer 5 made of a synthetic resin material on the convex side, and a filler 6 and reinforcing fibers (inorganic, organic, whiskers) 7. Is formed as an FRP plate body by lamination with the above. Bolt holes 8 are formed in the flange 3 at predetermined intervals.

As shown in FIG. 2, the hollow double part 4 has a front plate 9 on the convex side, and a coating film layer 5 continuous with the coating film layer 5 of the flange 3 is formed as necessary. 6 is formed as an FRP plate by laminating the fiber 7 and the woven fabric 10, and the back plate 11 is formed as an FRP plate by laminating the filler 6, the fiber 7 and the woven fabric 10, and the inside is formed in the hollow portion 12. Have been.

The hollow portion 12 is provided with a number of narrow columns 13 which are orthogonal to the front and back plates 9 and 11 and have a length of 3 mm to 10 mm. The filler 6 is impregnated and cured in the fiber bundle of the binding yarn 10D connected to the woven fabrics 10, 10. At the boundary between the hollow double part 4 and the flange 3, the front and back plates 9, 11
The thickness is gradually increased toward the outside to form a thick portion 14.

As shown in FIG. 3, a drain hole 15 penetrating inward and outward is formed in the thick portion 14, and this drain hole 15 enters the concave side when the antenna radome 1 is disposed so as to cover the front surface of the antenna. This is for draining rainwater from below, and the inner surface of the hole is covered with a protective material 15A.

The antenna radome 1 having this configuration has a diameter of, for example, 50 to 200 cm, and the thickness of the flange 3 and the hollow double section is, for example, 5 to 15 mm, and is appropriately selected depending on the required strength depending on the size. As the fiber used for FRP (fiber reinforced plastic), metal, glass, carbon, or the like is selected from inorganic, organic, and whiskers. Glass is selected from the viewpoint of cost and performance balance.

When the woven fabric 10 is woven as a double weave with a binding yarn interposed therebetween, as shown in FIG. 4, for example, as shown in FIG. 4, the upper weft 10A and the weft 10C are plain woven and the lower warp 10B is woven. Plain weave with weft 10C ...
D may be moved up and down every several 10C weft yarns, and may be arranged every several warp yarns (for example, every 5 mm of weft). When the weaving is not performed, the binding yarn 10D can be inserted into the upper and lower cloths and implanted. Also, a tufted fiber can be stabbed into a flat cloth, and the implanted cloth can be placed with the fluff facing the tufted cloth.

When the woven fabric 10 is impregnated with a filler, the woven fabric 10 is impregnated with the filler as shown in the right end portion of FIG. The upper and lower parts are attached so as to be thick. The material of the woven fabric 10 is, for example, glass fiber, synthetic resin fiber, carbon fiber,
It is selected from metal fibers and the like according to the application.

FIG. 5 is a rear view (recessed surface) of an antenna radome 1 according to a second embodiment. In this embodiment, the same members as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. The radome 1 for an antenna has a center P
Divided by two radiations L, L passing through
A ... Each of the divided bodies 2A has a substantially fan-shaped flat surface composed of isosceles and an arc curved edge, and the same flange 3 as the flange 3 of the first embodiment is formed on the arc curved edge by FRP.

Further, FRP flanges 16 project from the concave surface side at the isosceles end of each of the divided bodies 2A, and bolt holes 17 are formed in the flanges 16 at predetermined intervals along the longitudinal direction.
Are opened, and the flanges 1 between the two adjacent divided bodies 2A are formed.
It is configured such that the joints 6 and 16 can be joined by bolts 18 or an adhesive. That is, FIG.
7 is a side view of a state in which one of the divided bodies 2A is removed, and FIG. 7 shows a flange 16 part. The difference from the first embodiment is that there is a flange 16 and is formed by a plurality of divided bodies 2A. Are approximately the same.

FIG. 8 is a schematic view showing a manufacturing process. Formwork 1
The coating film layer 5 is formed on the concave surface 20 of the substrate 9 as required.
After the coating film layer 5 is cured, a laminate of a filler 6 such as a thermosetting synthetic resin or the like and a fiber 7 is formed on the surface thereof to a thickness of 1 to 3 mm, and the thick portion 14 is formed in accordance with the design. Make it thick.

Thereafter, a woven fabric 10 as shown in FIG. 4 is disposed on the surface of the woven fabric, and the filling material 6 is filled. 10D, it is transmitted to the upper side, is impregnated with the upper woven fabric 10, is integrally joined with the lower layered body, and the thin struts 13 are formed in a state where the filler 6 is impregnated with the joining yarn 10D. You. Then, a laminate of the filler 6 and the fiber 7 is formed thereon, and the thickness is increased according to the design at the thick portion 14.
The lamination of the filler 6 and the fibers 7 is repeated until the set flange thickness is reached.

The filler 7 is a honey-like gel, and when impregnated into a cloth, is impregnated substantially uniformly by capillary action, and
0D is orthogonal to the surface of the woven fabric 10, and the lower and upper portions of the binding yarn 10D are impregnated with the filler 7 by the surface tension due to surface tension, and are hardened in a relatively short time.
The thin strut 13 in which the filler 6 is impregnated in OD forms a hollow portion between the front and back FRP plates 9 and 11, and the front and back FRP plates 9 and 1.
1 is firmly supported and connected.

The present invention is not limited to the above embodiment. In place of the double woven cloth, when a cloth in which fluffs are planted is laid and a filler is impregnated, the fluffed fluffs become thin struts. In this case, the filling of the filler can be achieved as a result. In addition, the outer shape may be substantially hemispherical or flat, instead of being shaded.
Therefore, a substantially hemispherical shape or a flat shape is also included in the range of the design change of the substantially cap-shaped structure.

[0021]

The present invention constructed as described above has the following excellent effects. (1) Since it is constructed in a substantially hat-like shape on the side, the primary radiator can be covered sufficiently by covering it in front of the parabolic antenna, and the radiator and parabolic reflector can be protected from rain and snow. There is an effect that the antenna can be protected and an effect that the antenna receiving tower can be simplified by reducing the wind receiving area against the wind. (2) Since the substantially cap-shaped structure has a flange formed at the peripheral edge, it can be fixed to the support on the back side of the parabolic reflector of the parabolic antenna to completely cover the parabolic reflector. Since the main body is formed as a hollow double structure, even if the front and back plates are FRP plates, they can be made into thin plates themselves and have radio wave permeability. Synthetic resin material is impregnated into the binding yarn fiber of the cloth, which has radio wave permeability and is sparsely arranged to create space, minimizing loss when radio waves are transmitted. There is an effect that can be. (3) Since the substantially cap-shaped structure has a hollow double structure, the weight can be reduced, and even if it is directly mounted on the parabolic antenna, the steel tower for supporting the parabolic antenna is simplified, and the strength of the supporting material is maintained. There is an effect that the burden can be reduced. (4) In the case where a substantially cap-shaped component is composed of a divided body, it is easy to form a mold for producing a large-diameter component, the thickness is made uniform, and the isosceles side edge is improved. Since the flange is formed in the portion, there is an effect that the rigidity after assembly is ensured.

[Brief description of the drawings]

FIG. 1 is a side view of an antenna radome.

FIG. 2 is a longitudinal sectional side view of a main part of a substantially cap-shaped structure.

FIG. 3 is a vertical sectional side view of a main part of the substantially cap-shaped structure.

FIG. 4 is a cross-sectional view showing the relationship between the double cloth and the narrow struts.

FIG. 5 is a rear view of an antenna radome according to a second embodiment.

FIG. 6 is a side view of an antenna radome.

FIG. 7 is a cross-sectional view of a substantially cap-shaped structure showing a flange portion.

FIG. 8 is a partial cross-sectional view of a mold showing a manufacturing process of an antenna radome.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Radome for antenna 2 Approximately cap-like structure 2A Division 3 Flange 4 Hollow double part 5 Paint film layer 6 Filler 7 Fiber 8 Bolt hole 9 Table FRP board 10 Woven cloth 10A Upper warp 10B Lower warp 10C Weft 10D Binding yarn DESCRIPTION OF SYMBOLS 11 Back FRP board 12 Hollow part 13 Narrow column 14 Thick part 15 Drainage hole 16 Flange 17 Bolt hole 18 Bolt 19 Formwork 20 Concave mold surface

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasuo Nakajima 511 Mekata, Shimodate City, Ibaraki Prefecture Inside Taiei Shoko Co., Ltd. (72) Inventor Yasuhide Kaneko 3-50-1 Kamiishihara, Chofu City, Tokyo (56) References JP-A-61-253902 (JP, A) JP-A-6-283918 (JP, A) JP-A-62-240543 (JP, A) JP-A-1-319306 ( JP, A) JP-A-4-167706 (JP, A) JP-A-6-252623 (JP, A) JP-A-56-114101 (JP, U) JP-A-2-133008 (JP, U) (58) ) Surveyed field (Int.Cl. ⁷ , DB name) H01Q 1/42

Claims (3)

(57) [Claims] 1. A main body having a hollow double structure in which a front and back FRP plate and a hollow portion between the front and back FRP plates are connected and supported by countless thin columns, and an FRP flange formed on a peripheral edge of the main body. A front and back FRP plate formed by filling a synthetic resin filler into a double cloth of a pair of opposing fibers, wherein
The synthetic resin filler filled in the double cloth of the fibers is composed of a thin strut formed by impregnating the binding yarn fiber bundle connecting the double cloth and erecting and curing each binding yarn. Radome for antennas. 2. An antenna radome comprising a main body and a flange is composed of a combination of several sections divided by a plurality of radiations passing through the center thereof, and the arc curved edge of each section is FRP. The radome for an antenna according to claim 1, wherein a flange made of a single plate is formed, and an FRP flange for segmented body joining is protruded from an isosceles side end to a concave surface side. 3. A step of forming a coating film layer as necessary on a concave surface of a mold forming a substantially cap-shaped structure, and laying a double cloth of fibers thereon and filling with a synthetic resin filler. A step of impregnating the filler into the binding yarn fiber bundle of the double cloth and curing it upright, and a step of forming a flange by laminating a synthetic resin filler and fibers outside the peripheral end of the double cloth. And a step of forming bolt holes at predetermined intervals in the flange.