JPH0210641Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention relates to the improvement of waveguides for high-frequency circuits, and its characteristics are
In order to prevent the adjustment screw, which is used to cancel VSWR (reflection loss) or change the phase of radio waves, from rotating, a plate-shaped elastic member is attached to the screw.

First, before explaining this invention, a conventional waveguide will be explained.

FIGS. 1 and 2 are diagrams showing conventional waveguides, and a is a cross-sectional view of the waveguide b viewed from the direction of arrow A. FIG. In the figure, 1 is the waveguide body, 2a, 2
b is an adjustment screw, and 3a and 3b are locking nuts.

By the way, the positions of the adjustment screws 2a and 2b and the interval d between the screw portions are determined in advance by electromagnetic calculation, but the amount of protrusion of the screw portion into the inside of the waveguide body 1 is determined in advance. _a and 1 _b , while rotating the adjusting screws 2a and 2b, respectively, and stopping them at the optimum amount, and tightening the locking nut 3.
Fix with a and 3b. Finally, as shown in FIG. 2, the entire threaded portion is fixed with a conductive adhesive 4 for use.

However, in the conventional structure described above, as shown in FIG. 3, the adjustment screws 2a and 2b are close to each other,
When the distance d becomes smaller, the locking nuts 3a, 3
b also come close to each other and finally come into contact and lock nut 3
There was a problem that made it impossible to rotate a and 3b. As a solution, locking nut 3
There is a method of manufacturing the outer dimensions of a and 3b to be specially small, but it is clear that this method also has a limit when the distance d becomes extremely small.

This invention was made to improve this problem, and will be explained in detail below using figures.

FIG. 4 shows the structure of the waveguide according to this invention, and a is a cross-sectional view of b as seen from arrow A.

In the figure, reference numeral 5 denotes a plate-shaped elastic member according to this invention, which is connected to and attached to adjustment screws 2a and 2b. FIG. 5 is an enlarged view of the plate-like elastic member 5,
a is one embodiment, and b is another embodiment. Figure 5a
, 5 is a plate-like elastic member, 6a and 6b are first
These holes correspond to the positions of the adjustment screws 2a and 2b shown in FIGS.
It is set smaller than the outer diameters of a and 2b.

Further, in another embodiment b, the adjusting screws 2a, 2b
Notches 7a are made around the holes 6a and 6b corresponding to the holes 6a and 6b.
7b is provided.

Since the plate-like elastic member 5 is structured like this,
When the adjustment screws 2a, 2b are inserted, they are elastically deformed downward as shown in FIG. 6 along the insertion direction A, as shown in FIG. When the adjusting screw 2 stops in this state, tightening stress (hoop stress) is applied to the outer circumferential surface of the screw 2 due to elastic deformation of the plate-like elastic member 5. As a result, the rotational force of the adjusting screw 2a is transmitted to the plate-like elastic member 5, but
Since the plate-shaped elastic member 5 is also connected to the other adjusting screw 2b, the rotational forces are mutually resisted within the elastic stress of the plate-shaped elastic member 5, thereby achieving the effect of preventing the screw from rotating.

According to this invention, when the threaded portion is rotated during adjustment, a resistance force is generated due to the elastic deformation of the plate-like elastic member, but the magnitude of this resistance force is larger than that of a normal screwdriver. The diameter of the hole provided in the plate-like elastic member may be set to a sufficient extent. After the adjustment of the threaded portion is completed, the threaded portion is permanently fixed with a conductive adhesive 5 for use, as shown in FIG. 7, as in the case of a conventional waveguide.

As described in detail above, according to this invention, even if the intervals between adjacent adjustment screws are very close to each other, it is possible to prevent the threaded portion from rotating without using a lock nut. The plate-shaped elastic member may be a synthetic resin having elasticity molded into a plate shape, such as rubber, nylon, or acrylic resin, but other elastic bodies such as metal may also be effective.

Further, for convenience of explanation, the number of adjusting screws is two in the embodiment, but it goes without saying that the present invention can be applied even if there are two or more adjusting screws.

[Brief explanation of the drawing]

Figures 1 and 2 are diagrams showing the structure of a conventional waveguide, Figure 3 is a diagram showing a state in which the adjusting screw parts are close to each other, and Figures 4 and 7 are based on the present invention. A diagram showing the structure of the waveguide, FIG. 5 is an enlarged view of the plate-like elastic body, and FIG. 6 is an enlarged view of the adjusting screw portion. In the figure, 1 is the waveguide body, 2a and 2b are adjustment screws, 3 is a locking nut, 4 is a conductive adhesive, and 5
is a plate-shaped elastic member, 6a and 6b are holes, and 7a and 7b are notches. It should be noted that the same or corresponding parts in the figures are indicated by the same reference numerals.

Claims (1)

[Scope of utility model registration request] In a waveguide having a plurality of adjacent VSWR or phase adjustment screws, a plate-shaped elastic member with a hole smaller than the outer diameter of the adjustment screw is provided at a position corresponding to the adjustment screw. A waveguide characterized in that the screws are interconnected and attached to the outer surface of the waveguide.