JPS63266903A - Dielectric resonator - Google Patents

Abstract

PURPOSE:To prevent the reproducibility of a resonance frequency from being deteriorated by forming a silver electrode with a prescribed width from the end face of an inner dielectric case brought into contact with an inner wall face to the side face, uniformizing the shape of the electrode formed to the side face of the inner dielectric when bonding the inner dielectric onto the inner wall face of the case. CONSTITUTION:The dielectric resonator consists of an inner dielectric 1, silver electrodes 2, 3, a case 4 and silver pastes 9, 10. Through the constitution above, the inner dielectric 1 is made of a dielectric material having a high dielectric constant such as titanium oxide group ceramic and the silver electrodes 2, 3 with a prescribed width are formed to both end faces. The silver electrodes 2, 3 are formed by coating and baking the silver paste. Moreover, the side plate 4a of the case 4, the bottom plate 4b and the ceiling plate 4c are formed on the surface of the ceramics plate whose linear expansion coefficient is matched with that of the inner dielectric 1 by baking the silver conductor film.

Description

[Detailed description of the invention] (Al industrial application field The present invention relates to a 7M mode dielectric resonator.

(b) Conventional technology A 7M mode dielectric resonator has a column-shaped internal dielectric placed inside a case made of ceramics or a metal case with a conductive film formed on the surface, and a coupling loop inside the case. It is configured by providing coupling means such as. 4 and 5 show the structure of a conventional 7M mode dielectric resonator. Figure 4 is a cross-sectional view, where l represents a cylindrical internal dielectric, and 4a, 4b, and 4C are ceramic plates whose linear expansion coefficients match those of the internal dielectric, and plates in which a conductive film is formed on the surface are combined. This case is baked and hardened, and the inner surfaces of the bottom plate 4b and top plate 4C of this case (
9. Both end surfaces of the cylindrical internal dielectric are covered with silver paste (inner wall surface).9.
10 and baked and hardened.

(The problem that the C1 invention aims to solve However, in such a conventional dielectric resonator,
When joining the end face of the internal dielectric to the inner wall of the case, excess silver paste sometimes protruded. FIG. 5 is a diagram showing the joint portion between the top plate 4C of the case and the end surface of the internal dielectric 1. In the figure, 9 is a silver paste that joins the top surface of the internal dielectric 1 and the inner wall surface of the top plate 4c. However, as shown in the figure, the excess paste protrudes from the side surface of the internal dielectric 1, causing wavy unevenness, resulting in a problem in that the reproducibility of the pre-designed resonance frequency is reduced and the aesthetic appearance is impaired.

The purpose of this invention is to solve the above-mentioned conventional problems by making the shape of the electrodes formed on the side surfaces of the internal dielectric uniform when joining the columnar internal dielectric to the inner wall surface of the case. A dielectric resonator of the present invention has a columnar internal dielectric arranged inside a case, and the end face of this internal dielectric is covered with silver paste. The dielectric resonator is bonded to the inner wall surface and fired, and is characterized by the fact that silver electrodes of a constant width are formed from the end surface of the inner dielectric case in contact with the inner wall surface to the side surface.

(81 Effect) In the dielectric resonator of the present invention, the internal dielectric has silver electrodes of a certain width formed in advance from the end surface in contact with the inner wall surface of the case to the side surface. Even if excess silver paste protrudes when bonded, it will protrude onto the fixed-width silver electrode formed on the side of the internal dielectric, and the dimensions of the electrode formed on the side of the internal dielectric will not change. In addition, the protruding silver paste is not noticeable because it is made of the same material as the silver electrode formed in advance.Therefore, a dielectric resonator with high reproducibility of the resonance frequency and without spoiling the aesthetic appearance can be obtained.

if) Embodiment FIG. 1 is a sectional view showing the structure of a dielectric resonator according to an embodiment of the present invention, FIG. 2 is a view showing the joint between the end face of the internal dielectric and the inner wall of the case, and FIG. FIG. 3 is a partially cutaway perspective view showing the structure of the same dielectric resonator.

In Fig. 1, 1 represents a cylindrical internal dielectric, which is made of a dielectric material with a high dielectric constant such as titanium oxide ceramic, and silver electrodes 2 and 3 of a constant width are formed on the sides from both end faces. . This silver electrode is formed by applying silver paste, baking, etc. 4a is a side plate of the case, 4b is a bottom plate, and 4c is a top plate, each of which has a silver conductive film baked onto the surface of a ceramic plate whose linear expansion coefficient matches that of the internal dielectric. As shown in FIG. 3, these plates and the internal dielectric are assembled with silver paste and baked. As shown in FIG. 1, through holes are formed in the two opposing side plates 4a, and a signal input/output connector 5.7 is attached to these holes, and an inductive coupling loop 6.8 is installed inside the case. are respectively projected and input/output of signals is performed.

Figure 2 shows the joint between the end face of the internal dielectric and the inner wall of the case.
In particular, the connection portion between the upper end of the internal dielectric 1 and the inner wall surface of the top plate 4c is shown. As shown in the figure, a silver electrode 2 having a constant width is formed from the end face to the side face of the internal dielectric 1, and the top plate 4c and the inner wall surface are joined by silver paste 9.

During this bonding, silver paste is applied to either or both of the end face of the internal dielectric 1 and the inner wall of the case, and the bonded state is baked and hardened, but the silver paste 9 that protrudes from the end face of the internal dielectric It is integrated with the silver electrode 2 on the side.

As a result, the formation area of the silver electrode formed near the end face of the internal dielectric does not change, and variations in resonance frequency due to the protrusion of the silver paste are eliminated. Furthermore, the protruding grudge paste becomes less noticeable, so the aesthetic appearance is not impaired.

(g) Effects of the Invention As described above, according to the present invention, when bonding the internal dielectric to the inner wall surface of the case, it is possible to improve the reproducibility of the resonant frequency regardless of the amount of silver paste applied. It is possible to reduce appearance defects due to paste protrusion.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the configuration of a dielectric resonator according to an embodiment of the present invention, FIG. 2 is a view showing the joint between the inner wall surface of the case and the internal dielectric in the same dielectric resonator, and FIG. is a partially cutaway perspective view showing the structure of the same dielectric resonator, Fig. 4 is a cross-sectional view showing the structure of a conventional dielectric resonator, and Fig. 5 is a diagram showing the case inner wall surface and internal dielectric in a conventional dielectric resonator. It is a diagram showing a joint part with the body. 1-internal dielectric, 2,3-silver electrode, 4a, 4b, 4cm case, 9.10-silver paste.

Claims (1)

[Claims] (1) In a dielectric resonator in which a columnar internal dielectric is placed inside the case, and the end face of this internal dielectric is joined to the inner wall surface of the case with silver paste and then baked, the inside dielectric of the case is A dielectric resonator characterized in that a silver electrode of a constant width is formed from an end surface in contact with an inner wall surface to a side surface.