JPH0832306A - Dielectric filter - Google Patents

Abstract

PURPOSE:To perform coupling degree adjustment among resonators with a simple operation which is turning among the resonators by freely turnably attaching the plural resonators for constituting a dielectric filter to a supporting rod with screws. CONSTITUTION:The coupling degree adjustment of the plural pieces of the resonators 2 is performed by rotating and moving the resonators 2 screwed to the supporting rod 3 with the screws. In order to facilitate the turning movement of the resonators 2, for instance, a groove in a longitudinal direction is provided in a conductor case 1, it is performed through the groove and a lid is put over the groove after the adjustment is completed. Also, as the mode of the resonators 2, a TM mode or a TE mode is defined when the supporting rod 3 is a nonconductor and a TEM mode is defined when it is a conductor. Or, by turning male screws 1b at both ends to which input/output coupling probes 1c are attached, the coupling degree adjustment of input/output coupling is made possible as well.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric filter in which a plurality of resonators are rotatably housed in a conductor case by means of support rods with screws.

[0002]

2. Description of the Related Art Conventionally, the structure of this type of dielectric filter is shown in FIG. In the figure, reference numeral 10 is a three-division type cutoff waveguide, and a plurality of resonators 11 are fitted into a resin ring 12 made of expanded polyethylene and the resin ring 12 is press-fitted into the waveguide 10. ing. In addition, 13 is a connector and 14 is a coupling degree adjusting screw.

[0003]

However, in the dielectric filter of this conventional structure, when adjusting the coupling degree between the resonators 11, as shown in FIG. Therefore, the position of the resonator 11 should be easily adjusted, or 2) the coupling degree adjusting screw 14 should be inserted between the resonators 11. In this case, the following problems will occur. That is, in the case of 1), the division structure becomes complicated, and it is difficult to maintain the reproducibility of the coupling degree before and after the division and assembly.
In the case of 2), by inserting the coupling degree adjusting screw 14,
The unloaded Q of the resonator 11 will deteriorate.

Therefore, according to the present invention, the degree of coupling between the resonators can be adjusted by a simple operation of rotating the resonator that is rotatably attached to the threaded support rod. It is an object of the present invention to provide a dielectric filter which does not cause the problem of deterioration of the no-load Q due to the coupling degree adjusting screw which has been a problem in the conventional example.

[0005]

Means for solving the problems of the present invention are as follows. The present invention relates to an axially symmetric or quasi-axially symmetric resonator having a screw in the central part, or a plurality of axially symmetric or quasi-axially symmetric resonators in which a bush having a screw at the central part is fitted in the central part. , The plurality of resonators are housed through a threaded support rod rotatably attached at an appropriate interval, and a spacer that screws-couples the support rod to each other, and female screws are provided inside both ends. A dielectric filter comprising a formed conductor case, and male and female threads at both ends, which are rotatably screwed to female threads at both ends of the conductor case and to which an input / output coupling probe is attached.

[0006]

In the present invention, since a plurality of resonators are rotatably attached to the support rod with a screw, the coupling degree between the resonators can be adjusted by a simple operation of rotating the resonators. it can. Also, the coupling degree of the input / output coupling can be adjusted by rotating the male screws at both ends to which the input / output coupling probe is attached.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a partial cross-sectional view of an embodiment of the present invention. FIG. 2 is a sectional view taken along line XX of FIG. In FIG. 1 and FIG. 2, reference numeral 1 denotes a cylindrical conductor case, and female screws 1a are provided inside both ends thereof. This female screw 1a
A male screw 1b is rotatably attached to the. An input / output coupling probe 1c is attached to the male screw 1b at its central shaft portion.

Reference numeral 2 is an axially symmetric or quasi-axially symmetric resonator, which has a female screw at the center as shown in FIG. 3A or has a screw formed at the center as shown in FIG. 3B. The bush 2a is fitted to the center of the bush 2a.

Reference numeral 3 is a support rod with a screw, and a plurality of resonators 2
Are rotatably screwed at appropriate intervals.
After adjusting the plurality of resonators 2, the fixing nuts 2b are fixed.
It is fixed so that it will not rotate. The support rod with screw 3 to which the plurality of resonators 2 are attached is the conductor case 1
A plurality of resonators 2 are held and housed in a conductor case 1 by being supported by two spacers 4 which are fitted to the inside of the with a screw.

This embodiment has the above-mentioned structure, but the degree of coupling of the plurality of resonators 2 is adjusted by rotating the resonator 2 screwed to the threaded support rod 3. It is done by At that time, as shown in FIG.
The characteristic of the degree of coupling between resonators [%] with respect to the resonator spacing [mm] is referred to. To facilitate the rotational movement of the resonator 2, for example, a groove is provided in the longitudinal direction in the conductor case 1,
All you have to do is go through this groove. After the adjustment is completed, the groove may be covered. Also, the resonator 2
The mode is TM if the threaded support bar 3 is non-conductive.
_{It becomes 01δ} mode or TE _01δ mode. This embodiment shows the case of TM _{01 delta} mode. If the support rod 3 with screw is a conductor, the TEM mode is set.

[0011]

According to the present invention, since a plurality of resonators are rotatably attached to a support rod with a screw, the degree of coupling between the resonators can be adjusted by a simple operation of rotating the resonators. be able to. Also, the coupling degree of the input / output coupling can be adjusted by rotating the male screws at both ends to which the input / output coupling probe is attached.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

3A and 3B show a screwed support structure of the resonator shown in FIG. 1, where A is a configuration diagram of the resonator screwed to a threaded support rod by a screw formed at the center, and B is a screwed shape. Shape diagram of resonator with bush that is screwed to support rod fitted in the center

FIG. 4 is a characteristic diagram of a degree of coupling between resonators with respect to a resonator spacing in the present embodiment.

FIG. 5 is a partial cross-sectional view of a conventional example.

[Explanation of symbols]

 1 Conductor case 1a Female screw 1b Male screw 1c Input / output coupling probe 2 Resonator 2a Bushing 2b Fixing nut 3 Support rod with screw 4 Spacer

Claims (1)

[Claims] 1. A plurality of axisymmetric or quasi-axisymmetric resonators having a screw at the center, or a plurality of axisymmetric or quasi-axisymmetric resonators having a bush having a screw at the center fitted in the center. A plurality of resonators, the support rod with a screw being rotatably attached at an appropriate interval, and the support rod via a spacer screwed to the support rod. And a conductor case in which the conductor case is formed, and is rotatably screwed to female screws at both ends of the conductor case,
A dielectric filter comprising: a male screw at both ends to which an input / output coupling probe is attached.