JPS6281801A - Movable transmission line for microwave - Google Patents

Abstract

PURPOSE:To attain the curving in an optional direction by adopting a circular bellows structure for a moving part and providing a mode selector. CONSTITUTION:The moving transmission line consists of the moving part A of the circular bellows structure and a cross section changing part B1 converting the circular cross section into a rectangular cross section of a waveguide B2. The circular bellows structure of the moving part A is in waving form in the lengthwise direction and since the lateral cross section is formed circularly, the other end is being to one end in either direction, but the direction of the electric field in the moving part A is not defined. As the countermeasures, the mode selector made of a thin conductor 2 is provided to a part of II-II of the moving part A. Through the constitution above, the curing in an optional direction is attained.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a movable microwave transmission line.

[Conventional technology]

In order to direct the microwaves emitted from the antenna to the workpiece, the transmission line is flexible so that it can move in the axial direction and in the direction perpendicular to the axial direction.

Conventionally, such a movable microwave transmission line has a configuration as shown in FIG. That is, it consists of a tubular body having a rectangular opening with a width a and a height b (<a), and this tubular body has a so-called bellows structure that is wave-shaped in its length direction. A transmission line having such a configuration can efficiently transmit microwaves and is usually used in the TE01 mode.

And, as mentioned above, because it has a bellows structure,
It is curved not only in the length direction but also in the width a direction and the cavity b direction, so that the antenna connected once to this movable transmission path can be directed toward the workpiece.

[Problem that the invention seeks to solve]

However, when the above-mentioned movable transmission path is bent, for example, in the width a direction, that is, around one side corresponding to the height b, the moment required for this must be increased, so it is difficult to bend the movable transmission path easily. The problem was that I couldn't do it.

Further, there is a problem in that diagonal curvature at the opening of the movable transmission path requires a larger force.

Therefore, one object of the present invention is to provide a movable microwave transmission path that can be easily curved in any direction.

[Means for solving problems]

In order to achieve such an object, the present invention provides a movable part with a circular bellows structure, and a mode selector installed in the movable part to prevent changes in the direction of the electric field in the transmission path due to bending. It is something.

〔Example〕

FIGS. 1(a) and 1(b) are configuration diagrams showing one embodiment of a movable microwave transmission line according to the present invention.

FIG. 1(a) shows a plan view, and FIG. 1(b) shows a side view.

First, the movable transmission line has a movable part A, and each end has a cross-section changing part B1 and a rectangular waveguide B2 fixedly connected to this.
have. The rectangular waveguide B2 has a rectangular shape with a width a and a height b, and the cross-section changing portion B□ has a shape in which the opening changes from a rectangular shape to a circular shape, as shown in the perspective view of FIG. . The movable part A is connected to the circular opening of the cross-section changing part B1, and is constituted by a cylindrical bellows having the same diameter. This bellows structure has a wavy shape in the longitudinal direction, as shown in FIG. 3(a) or (b), which is a cross-sectional view thereof.

By configuring the movable part A with a cylindrical bellows in this way, one end of the movable part A can be moved relative to the other end, but the direction of the electric field within the movable part A will not be constant. For this reason, a mode selector is formed at the location indicated by the line 1--2 shown in FIG. 1(a) to maintain the direction of the electric field constant. As shown in FIG. 4, which is a cross-sectional view taken along the line ■-■, this mode selector uses a thin conductor 2.
is being set up. In the mode selector made up of these thin conductors 2, the arrangement or number of conductors 2 is set depending on the mode.

The movable transmission line configured in this way has a cylindrical bellows structure in its movable part, so no matter which direction you try to bend the waveguide at one end with respect to the other end, the moment is the same, so it requires less effort. become easily achievable. Moreover, since a mode selector is installed in the movable part to keep the direction of the electric field constant, the disadvantages of having the movable part of the waveguide in a cylindrical shape can be avoided.

〔Effect of the invention〕

As is clear from the above explanation, the microwave movable transmission line according to the present invention can be easily curved in any direction.

[Brief explanation of drawings]

FIGS. 1(a) and 1(b) are configuration diagrams showing one embodiment of a movable microwave transmission path according to the present invention, FIG. 1(a) is a plan view, FIG. 1(b) is a side view, FIG. 2 is a perspective view showing a cross-sectional change part of the movable transmission path, FIGS. 3('a) and (b) are sectional views showing the bellows part of the movable part of the movable transmission path, and FIG. 4 is a perspective view showing the movable section of the movable transmission path. A cross-sectional view showing a mode selector installed in the
FIG. 5 is a configuration diagram showing an example of a conventional movable transmission line. A... Movable part, B1... Cross section changing part, B2... Rectangular waveguide, 2... Conductor.

Claims (1)

[Claims] In a microwave movable transmission path comprising a movable waveguide with rectangular waveguides connected to both ends, the movable waveguide has a flexible cylindrical portion and an opening shape at each end of the movable waveguide. a cross-sectional changing section having a cross section that changes to the shape of the opening of the wave tube, and a mode selector that maintains the direction of the electric field constant by curving the movable wave guide. movable transmission line.