JPS6338886B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a corrugated horn serving as a primary radiator of a Cassegrain antenna and a method for manufacturing the same.

Conventionally, such corrugated horns have been manufactured by casting a metal material or by cutting an aluminum round bar into a tapered hollow material and cutting a desired corrugated groove into the inner periphery using a lathe. was. In this method, since the inner diameter is tapered in the axial direction, it is very difficult to process the depth, width, etc. of the corrugated groove on the inner periphery, and the manufacturing efficiency is poor, making it unsuitable for mass production. It was expensive, and because it was made of aluminum, it was heavy.

An object of the present invention is to eliminate such conventional drawbacks and provide a dielectric corrugated horn that is lightweight and suitable for mass production.

Another object of the present invention is to provide a method for manufacturing the above dielectric corrugated horn at low cost using a mold.

The dielectric corrugated horn according to the present invention is formed by forming a corrugated groove on the outer peripheral surface of a hollow dielectric, and forming a metal film on the outer peripheral groove of the dielectric. For example, after forming a horn material by laminating fiber-reinforced plastic (FRP) on the inside of a split mold in which a desired corrugated groove is formed on the inner wall surface of each mold, the formed horn material is removed from the split mold,
By performing aluminum metal spraying or adhesion on the outer peripheral groove of this material, it can be easily manufactured without using machining such as cutting.

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

FIG. 1 is a schematic diagram showing the manufacturing process of a conventional corrugated horn. Conventionally, the corrugated horn 2 was manufactured by cutting a desired corrugated slot 2a into an aluminum round bar 1 using a cutting tool 3 using an NC lathe or the like. In this method, the outer peripheral end of the aluminum round bar 1 has to be chucked on a lathe and rotated while machining the tapered slot, so it takes a lot of time to set dimensions such as groove depth and groove width. It's also inefficient.

FIG. 2 is a schematic diagram showing an embodiment of the manufacturing method according to the present invention in the order of steps. First, a split mold 5 having a desired corrugated groove 5a on the inner circumferential wall is prepared, a dielectric material such as FRP is laminated on the inner wall of this split mold 5, and a corrugated mold corresponding to the inner groove of the mold is formed on the outer periphery. A dielectric corrugated horn material 4 provided with grooves 4a is molded. After the split mold 5 is separated and the corrugated horn material 4 is demolded, aluminum composite is thermally sprayed from a thermal spray nozzle 6 into the corrugated groove portion 4a of the outer wall of the material to form an aluminum metal film on the outer periphery of the material. This metal film blocks leakage of electromagnetic waves that pass through the hollow part of the dielectric horn material, so a primary radiator that functions as a corrugated horn is obtained. Note that the dielectric material used in the present invention is not necessarily limited to FRP, but may be any other suitable dielectric material, and the metal film formed on the outer periphery may be made of not only aluminum but also other metals such as thermal spraying, vapor deposition, or adhesion. But that's fine.

As described above, according to the present invention, by providing a desired corrugated groove on the outer periphery of the horn, it becomes possible to manufacture the horn using a mold, and since it is a molding process, the same product can be mass-produced, thereby improving production efficiency. Moreover, the overall cost is lower and the resulting corrugated horn is much lighter than conventional one-piece metal corrugated horns manufactured by cutting or casting.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the manufacturing process of a conventional corrugated horn, and FIG. 2 is a schematic diagram showing the manufacturing process according to an embodiment of the present invention. 4...Dielectric corrugated horn material, 4a...
Corrugated groove on the outer periphery of the material, 5...Divided type, 5a
...Corrugated groove on the inner wall of the mold, 6...Aluminum spray nozzle.

Claims (1)

[Scope of Claims] 1. A dielectric corrugated horn comprising: a hollow dielectric member having a corrugated groove formed on its outer circumference; and a metal film formed on the outer circumference of the dielectric. 2. A dielectric material characterized by forming a dielectric corrugated horn material having corrugated grooves on the outer periphery using a split mold with corrugated grooves formed on the inner wall, and then performing metal spraying or adhesion on the outer periphery of the corrugated horn material. Method of manufacturing body corrugated horn.