JP2001160704A - Spherical dielectric resonator and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spherical dielectric resonator in which only one resonance peak is obtained by enhancing the symmetry of the structure, and a method of manufacturing the same. SOLUTION: This spherical dielectric resonator 100 is mounted on a metal cavity 2 having a cubic space, a spherical dielectric ceramics 1 arranged at a center position of the space inside the cavity 2, and a wall of the cavity 2. A metal output probe 5 is disposed near the dielectric ceramics 1 and has a tip end for taking out resonance energy, and is mounted on the wall of the cavity 2 opposite to the output probe 5 with the dielectric ceramics 1 as a center. Its center axis is set to be the same as the center axis of the output probe 5 and a metal frequency adjusting screw 4 for adjusting the resonance frequency, and a spherical dielectric ceramic 1 filled to fill the space in the cavity 2. The main part is constituted by the fluororesin 3 which fixes and supports the.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spherical dielectric resonator applied to a filter, a resonator and the like in a microwave band and a method of manufacturing the same. And a method of manufacturing the same.

[0002]

2. Description of the Related Art As a spherical dielectric resonator of this kind, for example, as shown in FIG. 4, a metal cavity 2 having a cubic space, and a spherical dielectric fixed at the center of the space inside the cavity 2 are shown. Body ceramics 1, a rod-shaped support base 6 made of a fluororesin that supports the dielectric ceramics 1, mounted on the wall surface of the cavity 2 and its tip end is arranged near the dielectric ceramics 1 and reduces resonance energy. A rod-shaped output terminal (output probe) 5 for taking out and mounted on the wall surface of the cavity 2 opposite to the rod-shaped output terminal 5 with the dielectric ceramic 1 at the center, and the central axis thereof is the same as the central axis of the output terminal 5 The main part is known with the frequency adjusting screw 4 set to the above.

In this spherical dielectric resonator, TE1
The resonance mode called the 01 mode is the lowest-order mode, and this resonance mode is most easily used industrially. For example, according to a document by Nakakita et al. (Proceedings of the 1989 Spring Meeting of the Institute of Electronics, Information and Communication Engineers, volume 2-p546, Hisao Nakakita, Kazuo Imai, "Millimeter-wave spherical dielectric resonator"). A TE101 mode 38 GHz band rejection filter is realized by using spherical dielectric ceramics having a relative dielectric constant of 24 and 6 mm.

[0004] This type of spherical dielectric resonator has a feature that a high no-load Q value can be realized because the ceramic has no corners as compared with a cylindrical dielectric resonator that has been widely used in the past. Have. Further, in the millimeter wave band, the processing of the spherical ceramic is easier than the processing of the columnar ceramic, so that the application in the millimeter wave band is advantageous.

[0005]

Since the spherical dielectric resonator has a symmetric structure with respect to three orthogonal axes, many resonance modes including the TE101 mode have triple degenerate modes. Becomes Therefore, if there is a structure that is slightly asymmetrical with respect to each of the three orthogonal axes, the triple degenerate mode is solved, and three independent resonance peaks are generated.

In particular, this phenomenon is often caused by a mechanism for supporting the spherical dielectric ceramic 1 in the metal cavity 2 as shown in FIG. That is, as shown in FIG. 4, the mechanism for supporting the spherical dielectric ceramics 1 by the bar-shaped support 6 from one direction has a structure that is asymmetric with respect to the other two orthogonal axes. There is a problem that one resonance peak is separated into two or more resonance peaks, thereby deteriorating the characteristics as a resonator.

The present invention has been made in view of such a problem, and an object thereof is to improve the symmetry of the structure so that only one resonance peak can be obtained. And a method of manufacturing the same.

[0008]

That is, according to the first aspect of the present invention, there is provided a cavity having a cubic space, a spherical dielectric ceramic fixed at a center position of the space in the cavity, and A rod-shaped output terminal for mounting and having a tip portion disposed near the dielectric ceramic and for extracting resonance energy,
A spherical dielectric resonator having a frequency adjusting screw whose center axis is set to be the same as the center axis of the output terminal, which is mounted on the cavity wall opposite to the rod-shaped output terminal with the dielectric ceramics at the center. Wherein the spherical dielectric ceramic is fixed with a fluorine-based resin filled so as to fill the cavity space.

According to the spherical dielectric resonator according to the first aspect of the present invention, the spherical dielectric ceramic is fixed by the fluorine resin filled so as to fill the cavity space. Since the incorporation of a rod-shaped support that hinders the symmetry of the structure is not required, it is possible to obtain only one resonance peak without causing the separation of the resonance peaks caused by the decompression of the triple mode. .

Next, claim 2, claim 3, and claim 4
The invention according to claim 1 relates to an invention that specifies a method for manufacturing a spherical dielectric resonator according to claim 1.

That is, the invention according to claim 2 is based on the method of manufacturing a spherical dielectric resonator according to claim 1, and the respective central axes are set on the same axis on a pair of opposed cavity wall surfaces. A first supporting screw and a frequency adjusting screw corresponding to the rod-shaped output terminal are respectively mounted on the first supporting screw, and the first supporting screw and the frequency adjusting screw are arranged so that a spherical dielectric ceramic is arranged at a center position of the cavity space. A step of clamping the dielectric ceramic at each tip of the screw, and a step of filling the uncured fluorine resin so as to fill the cavity and fixing the dielectric ceramic by curing the resin. A step of pulling out the first support screw and attaching a rod-shaped output terminal to the part thereof, wherein the invention according to claim 3 is characterized in that:
A first supporting screw corresponding to the rod-shaped output terminal so that the center axes are set on the same axis on a pair of opposing cavity walls, based on the method of manufacturing the spherical dielectric resonator according to claim 1. And the second support screw corresponding to the frequency adjustment screw, respectively, and, each of the first support screw and the second support screw so that a spherical dielectric ceramic is disposed at the center position of the cavity space A step of sandwiching the dielectric ceramic at a tip end, a step of filling an uncured fluororesin so as to fill the space in the cavity, and curing the same to fix the dielectric ceramic; A step of pulling out the supporting screw and the second supporting screw, and attaching a rod-shaped output terminal and a frequency adjusting screw corresponding to each part, respectively.

Further, the invention according to claim 4 is based on the method of manufacturing a spherical dielectric resonator according to claim 2 or 3, wherein the first supporting screw and the frequency are fixed in the step of holding the dielectric ceramic. The dielectric ceramic is sandwiched between the tip of the adjusting screw or the tip of the first support screw and the tip of the second support screw, and the tip of an additional support screw attached to another cavity wall surface. And, after fixing the dielectric ceramics, pull out the additional support screw attached to the other cavity wall surface, inject uncured fluororesin into the hole, and cure it to close the hole. It is characterized by doing.

[0013]

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

FIG. 1 is a schematic perspective view showing the structure of a spherical dielectric resonator according to the present invention, in which the upper side wall surface is not shown and the inside of the metal cavity is shown in a transparent manner.

That is, the spherical dielectric resonator 100
As shown in FIG. 1, a metal cavity 2 having a cubic space, a spherical dielectric ceramic 1 disposed at the center of the space inside the cavity 2, and a tip mounted on the wall of the cavity 2 A metal output probe 5 disposed near the dielectric ceramic 1 and for extracting resonance energy, and a dielectric ceramic 1
And a metal frequency adjusting screw 4 for adjusting the resonance frequency, the center axis of which is set to be the same as the center axis of the output probe 5 and mounted on the wall surface of the cavity 2 opposite to the output probe 5 with the center as the center. The main part is composed of a fluorine-based resin 3 filled so as to fill the space inside the cavity 2 and fixing and supporting the spherical dielectric ceramics 1.

According to the spherical dielectric resonator 100, the spherical dielectric ceramics 1 is fixed and supported by the fluorine-based resin 3 filled so as to fill the space inside the cavity 2. There is no need to incorporate a rod-shaped support that inhibits the symmetry, and the symmetry of the structure is thereby increased, so that there is an advantage that only one resonance peak can be obtained without causing separation of the resonance peak.

Incidentally, in the spherical dielectric resonator 100, the spherical dielectric ceramics 1 needs to be fixed at the center position of the space in the cavity 2, so that the dielectric ceramics 1 is fixed by the following procedure. Done.

First, as shown in FIG. 2, a hole (not shown) is provided in the wall surfaces of a pair of cavities 2 opposed to each other, and a first support screw 50 corresponding to the output probe 5 is provided in one of the holes.
And the frequency adjustment screw 4 is inserted into the other hole, and the first support screw 50 and the frequency adjustment screw 50 are adjusted so that the spherical dielectric ceramics 1 is disposed at the center of the space in the cavity 2. The dielectric ceramics 1 is sandwiched between each end of the screw 4 (claim 2). The holes are provided in advance so that the respective central axes of the first supporting screw 50 and the frequency adjusting screw 4 are set coaxially.

Next, an uncured fluororesin [for example, polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (PFEP), tetrafluoroethylene- Perfluoroalkyl vinyl ether copolymer (PFA), etc.] and cure. When the uncured fluororesin is filled, one of the walls of the cavity 2 (excluding the wall where the first supporting screw 50 and the frequency adjusting screw 4 are mounted) is opened, and the fluororesin is opened from the opening. After filling, the opening may be closed, or an opening for injection may be opened in one of the walls of the cavity 2, and after filling the opening with the fluororesin, A method of closing the opening with the same material as the cavity 2 may be adopted.

Here, it is known that a fluorine-based resin is not generally bonded to a metal or the like after curing. Therefore,
After the fluororesin is cured, the dielectric ceramic 1
Can be pulled out by rotating the first support screw 50 and the like that sandwich and support the. As a result, except for the portion where the first support screw 50 and the frequency adjusting screw 4 were located, the other portions are completely filled with the fluororesin, and the spherical dielectric ceramics 1 is positioned at the center of the space inside the metal cavity 2. Fixed to

Thereafter, the output probe 5 was attached to the hole of the first support screw 50 that was removed, and the frequency adjustment screw 4 was appropriately moved while being rotated and fixed at an optimum position as shown in FIG. The spherical dielectric resonator 100 is manufactured.

A second support screw is applied in place of the frequency adjustment screw 4, and after the dielectric ceramics 1 is fixed, the second support screw is pulled out and the frequency adjustment screw 4 is inserted into its hole.
Alternatively, a mounting method may be adopted (claim 3). Alternatively, as shown in FIG. 3, in addition to the first support screw 50 and the frequency adjustment screw 4, additional support screws 51, 52 are attached to the wall surface of the other cavity 2, and these four screws 50, 4,.
A method of sandwiching and holding the dielectric ceramics 1 between 51 and 52 may be adopted (claim 4). In this case, after fixing the dielectric ceramics 1, the additional support screws 51, 5
It is necessary to inject an uncured fluororesin into each of the holes from which 2 has been removed and to cure the resin to close the holes.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As a spherical dielectric ceramic, the diameter is 1.
8 mm, using Ba, Mg, Ta oxide-based ceramics (relative dielectric constant 24), and as a metal cavity,
A spherical dielectric resonator was experimentally manufactured using a brass having a cubic space with an inner size of 5 mm × 5 mm × 5 mm and having a silver plated surface. In addition, an M1.6 brass silver-plated screw was used for the frequency adjustment screw, and a 0.5 mm diameter metal (beryllium copper alloy) rod-shaped probe was used as the output probe. PTFE was applied as a system resin.

The prototype spherical dielectric resonator is about 37.5.
It was confirmed that resonance occurred at GHz. At this time, by providing the output probe and the frequency adjusting screw, one resonance mode of the triple mode was separated and two resonance peaks were generated. , And as a result, one resonance peak could be obtained.

[0025]

According to the spherical dielectric resonator according to the first aspect of the present invention, since the spherical dielectric ceramic is fixed by the fluorine resin filled so as to fill the cavity space, the structure is improved. Therefore, there is no need to incorporate a rod-shaped support table that hinders the symmetry of the above, so that there is an effect that only one resonance peak can be obtained without causing the separation of the resonance peak due to the degeneration of the triple mode.

According to the method for manufacturing a spherical dielectric resonator according to the second to fourth aspects of the present invention, there is an effect that the spherical dielectric resonator according to the first aspect can be manufactured simply and easily.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing the structure of a spherical dielectric resonator according to the present invention.

FIG. 2 is a schematic perspective view showing one step of a method for manufacturing a spherical dielectric resonator according to the present invention.

FIG. 3 is a schematic perspective view showing one step of a method for manufacturing a spherical dielectric resonator according to a modification of the present invention.

FIG. 4 is a schematic perspective view showing the structure of a conventional spherical dielectric resonator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spherical dielectric ceramics 2 Cavity 3 Fluorine resin 4 Frequency adjustment screw 5 Output probe 100 Spherical dielectric resonator

Claims (4)

[Claims] 1. A cavity having a cubic space;
A spherical dielectric ceramic fixed at the center position of the space in the cavity, a rod-shaped output terminal mounted on the cavity wall surface and having a tip portion disposed near the dielectric ceramic and for extracting resonance energy, A spherical dielectric resonator comprising: a frequency adjusting screw mounted on the cavity wall surface opposite to the rod-shaped output terminal with the dielectric ceramic as a center and having a central axis set to be the same as the central axis of the output terminal; A spherical dielectric resonator, wherein the spherical dielectric ceramic is fixed by a fluorine resin filled so as to fill a cavity space. 2. A method of manufacturing a spherical dielectric resonator according to claim 1, wherein said first and second output terminals correspond to said rod-shaped output terminals so that respective central axes are set on the same axis on a pair of opposing cavity walls. Attach the supporting screw and the frequency adjusting screw respectively, and set the dielectric material at each tip of the first supporting screw and the frequency adjusting screw so that the spherical dielectric ceramic is arranged at the center position of the space in the cavity. A step of sandwiching ceramics, a step of filling an uncured fluororesin so as to fill the space in the cavity and curing the same to fix the dielectric ceramics, and pulling out the first support screw to A method of manufacturing a spherical dielectric resonator, comprising the steps of: attaching a rod-shaped output terminal to a part. 3. A method of manufacturing a spherical dielectric resonator according to claim 1, wherein said first and second output terminals correspond to said rod-shaped output terminals such that respective central axes are set on the same axis on a pair of opposing cavity walls. The first supporting screw and the second supporting screw are attached so that the supporting screw and the second supporting screw corresponding to the frequency adjusting screw are respectively attached, and the spherical dielectric ceramic is arranged at the center position of the cavity space. A step of sandwiching the dielectric ceramic at each tip of the screw, and a step of filling the uncured fluororesin so as to fill the cavity and fixing the dielectric ceramic by curing the resin. A step of pulling out the first support screw and the second support screw and attaching a rod-shaped output terminal and a frequency adjustment screw corresponding to each part, respectively, Method for producing a dielectric resonator. 4. In the step of sandwiching the dielectric ceramic, in addition to the respective tip portions of the first supporting screw and the frequency adjusting screw or the respective tip portions of the first supporting screw and the second supporting screw, another cavity is provided. The dielectric ceramic is sandwiched between the tip of the additional support screw attached to the wall surface, and
After fixing the dielectric ceramic, pull out the additional support screw attached to the wall surface of the other cavity, inject uncured fluororesin into the hole, and cure it to close the hole. The method for manufacturing a spherical dielectric resonator according to claim 2 or 3, wherein: