JPH03165605A - Dielectric resonator - Google Patents

Abstract

PURPOSE:To adjust the resonance frequency efficiently and to improve the mass-productivity by removing a dielectric substance of a resonator at the open end face side and removing part of an inner conductor and/or an outer conductor at the open end face side. CONSTITUTION:The resonance frequency is decided by removing part of the end ridge of an inner conductor 4 and/or an outer conductor 2 at the open end face side of a dielectric resonator in which the inner conductor 4 is formed in the inside of a dielectric block 1 and the outer conductor 2 is formed at least at the outer side face. Thus, part of the end ridge of an inner conductor 4 and/or an outer conductor 2 at the open end face side of the dielectric resonator is removed in this way to remove part of the inner conductor 4 and/or the outer conductor 2 at the open end face side together with the dielectric substance thereby decreasing the capacitive component near the open end of the dielectric resonator and varying the resonance frequency over a comparatively wide range in an increasing direction.

Description

Detailed Description of the Invention (a) Industrial Application Field This invention forms an inner conductor inside a dielectric block,
The present invention relates to a dielectric resonator having an outer conductor formed thereon.

(b) Prior art A conventional dielectric resonator of this type is, for example, a dielectric coaxial block in which an inner conductor is formed on the inner wall of a cylindrical dielectric block, and an outer conductor is formed on the outer surface and, if necessary, the bottom surface. An example is a resonator. Such a dielectric coaxial resonator is used alone as a resonator in an oscillation circuit, or together with several dielectric resonators in a duplexer, a bandpass filter, etc. In this case, the resonant frequency of the dielectric coaxial resonator The dielectric constant of the dielectric material and the dimensions of each part are designed to have a predetermined value.

However, the resonant frequency usually varies due to the influence of the dimensional accuracy of the dielectric block after sintering. Therefore, conventionally, the resonant frequency has been finely adjusted by cutting off a part of the open end face of the dielectric coaxial resonator.

FIG. 5 is an external perspective view of a dielectric coaxial resonator whose resonance frequency is adjusted. In the figure, 1 is a dielectric block in which a through hole 3 for forming an inner conductor is formed.
An inner conductor 4 made of a metal film is formed on the inner wall of the through hole 3. Further, an outer conductor 2 made of a metal film is formed on the side surface and, if necessary, the bottom surface of the dielectric block l. Conventionally, the dielectric constant near the open end of the dielectric coaxial resonator was reduced by removing part of the dielectric block from the open end surface of the dielectric coaxial resonator configured in this way to form the deleted portion 6. The resonant frequency is adjusted in the upward direction.

In addition, as a method to adjust the resonant frequency in the downward direction,
There is a method of increasing the capacitance component by attaching another dielectric chip to the open end surface of the dielectric coaxial resonator, and a method of increasing the inductive component by scraping off a part of the electrode on the short-circuited surface of the resonator.

(C1 Problem to be Solved by the Invention) However, in the method of removing a part of the dielectric block at the open end surface of the resonator as shown in FIG. The decrease in dielectric constant, that is, the amount of decrease in the capacitance component, is small.Therefore, the amount of change in the resonance frequency is small, and it has not been possible to efficiently adjust the resonance frequency over a relatively wide range.

The above-mentioned problems to be solved are not limited to dielectric coaxial resonators, but also apply to integrated multistage dielectric resonators in which a plurality of resonators are configured in a dielectric block.

An object of the present invention is to provide a dielectric resonator that allows efficient adjustment over a relatively wide range when adjusting the resonance frequency in the direction of increasing it.

(d) Means for Solving the Problems This invention forms an inner conductor inside a dielectric block,
A dielectric resonator having an outer conductor formed on at least the outer surface thereof is characterized in that a part of the edge portion of the inner conductor and/or the outer conductor on the open end surface side is removed to determine the resonant frequency.

(81 Effect) In the dielectric resonator of the present invention, a portion of the inner conductor and/or the edge portion on the open end surface side of the outer 4 members is removed, so that the inner conductor is removed together with the dielectric at the open end surface of the resonator. and/or a part of the outer conductor is also removed.Therefore, the capacitance component between the inner conductor and the outer conductor near the open end of the dielectric resonator is relatively significantly reduced.For this reason, the resonant frequency is compared. The resonant frequency can be varied in the upward direction over a wide range, and the resonance frequency can be efficiently adjusted during production.

(f) Embodiment FIGS. 1(A) and 1(B) show external perspective views of a dielectric resonator according to a first embodiment of the present invention. 1 in both figures
is a dielectric block in which a through hole 3 for forming an inner conductor is formed. An inner conductor 4 made of a metal film is formed on the inner wall of the through hole 3, and an outer conductor 2 made of a metal film is formed on the side and bottom surfaces of the dielectric block l. The inner conductor 4 is connected to the outer conductor 2 at the bottom surface. This constitutes a dielectric coaxial resonator whose top surface in the figure is an open end surface and whose bottom surface is a short-circuited end surface.

In both cases shown in FIGS. 1A and 1B, the ``deleted portion 6'' is formed by deleting a part of the edge portion of the outer conductor on the open end surface side of the resonator. Figure 1 (A)
is an example in which the capacitance component between the inner conductor 4 and the outer conductor 2 near the open end of the resonator is relatively greatly reduced by mainly deleting a part of the outer conductor 2, and the resonant frequency is relatively greatly increased. It is. Furthermore, in FIG. 1(B), the dielectric constant between the inner conductor 4 and the outer conductor 2 near the open end of the resonator is increased by reducing the amount of the outer conductor 2 and mainly removing the dielectric block 1. This is an example in which the resonant frequency is lowered and the resonant frequency is increased with a relatively small change width.

As described above, since the rate of change in the resonance frequency is different depending on the deletion of the outer conductor 2 and the deletion of the dielectric block 1, the former can be performed as a coarse adjustment, and the latter can be performed as a fine adjustment. For example, by using a dielectric resonator as a filter and grinding it using a small grinding tool while measuring its filter characteristics with a network analyzer or the like, the resonant frequency can be efficiently adjusted.

Next, FIG. 2 shows the appearance of a dielectric coaxial resonator according to a second embodiment of the present invention. This dielectric coaxial resonator is an example in which a removed portion 6 is formed by removing a portion of the edge portion of the inner conductor 4 on the open end surface side. By removing the dielectric plot together with a part of the electrode on the inner conductor side in this way, the capacitance component between the inner conductor 4 and the inner conductor 2 near the open end (J) of the resonator is reduced, and the resonant frequency can be raised.

Next, external perspective views of integrated dielectric resonators according to third and fourth embodiments of the present invention are shown in FIGS. 3 and 4. In both figures, 1 is a dielectric block, inside which is a through hole 3a for forming an inner conductor.

3b, and an electromagnetic field coupling through hole 5 located between these two through holes. Inner conductors 4a and 4b made of metal films are formed on the inner walls of the through holes 3a and 3b, and outer conductors 2 made of metal films are formed on the four side surfaces and the bottom of the dielectric block l. Further, the inner conductor 4 is connected to the outer conductor 2 at the bottom surface. In this way, an integrated dielectric resonator is constructed in which the top surface is an open end surface and the bottom surface is a short-circuited end surface.

In the example shown in FIG. 3, the resonant frequency of the resonator by the inner conductor 4b is adjusted by removing the edge portion on the open end surface side of the outer conductor 2 adjacent to the inner conductor 4b to form a deleted portion 6. There is.

On the other hand, in the example shown in FIG. 4, a portion of the edge portion on the open end surface side of the inner conductor 4a is deleted to form a deleted portion 6, thereby adjusting the resonant frequency of the resonator by the inner conductor 4a. There is.

In the first and second embodiments, a cylindrical dielectric coaxial resonator is used as an example, but the present invention can be similarly applied to a rectangular cylindrical dielectric coaxial resonator. Further, in both the coaxial resonator and the integrated resonator, the resonant frequency may be adjusted by removing both the inner conductor and the outer conductor. In addition, in some cases other tuning methods to tune the resonant frequency downward (
This method may also be combined with a method of attaching a dielectric chip to a dielectric block, a method of removing part of the electrode on the short-circuit side, etc.).

(g1 Effect of the invention According to this invention, since the dielectric material which is troublesome at the open end of the resonator is removed and a part of the troublesome open end of the inner conductor and/or outer conductor is removed, the amount of change in the resonant frequency is large. , the resonance frequency can be adjusted efficiently, improving mass productivity.

[Brief explanation of the drawing]

1A and 1B are external perspective views showing the structure of a dielectric coaxial resonator according to a first embodiment of the present invention, and FIG. 2 is a dielectric coaxial resonator according to a second embodiment. FIG. Figures 3 and 4 are the third and fourth diagrams of this invention.
1 is an external perspective view of an integrated dielectric resonator according to an example of FIG. FIG. 5 is an external perspective view of a conventional dielectric coaxial resonator. 1-dielectric block, 2-outer conductor, 3-through hole, 4-inner conductor, 6-deletion part.

Claims (1)

[Claims] (1) In a dielectric resonator in which an inner conductor is formed inside a dielectric block and an outer conductor is formed on at least the outer surface, a part of the edge portion of the inner conductor and/or the outer conductor on the open end surface side. A dielectric resonator characterized in that the resonant frequency is determined by removing the .