JPH05160603A - Dielectric filter - Google Patents

Abstract

PURPOSE:To reduce the number of parts and man-hour of assembling to reduce the cost by coupling first and second filter constituting members to assemble a dielectric filter and cascading dielectric coaxial resonators as their constituting elements by coupling circuit parts of an electrode. CONSTITUTION:A dielectric filter 1 consists of a resonator constituting member 2 as a first filter constituting member to be a part of a dielectric coaxial resonance part, a base substrate 3 as a second filter constituting member to constitute an internal unit, and a cover 4 which protects the side of a surface 31 and ground the case. In this constitution, plural recessed grooves 22 are provided on the surface facing the substrate 3 of the member 2, and conductors 32a to 32c of the electrode provided on the substrate 3 are fitted to these grooves to connect a conductor film 5 provided on side faces of the member to the outer conductor 32a and the inner conductor 32b out of electrode conductors provided on the substrate 3, thereby completing each dielectric coaxial resonator 6 constituting the filter 1. Thus, the resonator 6 and the unit 8 are assembled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric filter structure in which a plurality of dielectric coaxial resonators are connected in cascade.

[0002]

2. Description of the Related Art FIG. 11 is an exploded perspective view showing an example of the structure of a conventional dielectric filter. A conventional dielectric filter 10 includes a plurality of dielectric coaxial resonators 11 formed by coating a cylindrical dielectric made of ceramics or the like on an outer peripheral surface and an inner peripheral surface except for one end surface 11a with a conductive material and coupling electrodes 12a. The filter main body 13 is configured by being coupled to each other via the coupling substrate 12 on which the filter main body 13 is formed.
Are housed in cases 14 and 14 '.

An input / output terminal 15 for guiding a signal is attached in a protruding manner to the open end surface 11a side of the hole 11b forming the inner conductor of the dielectric coaxial resonator 11, and each dielectric coaxial resonator 11 is attached. , The input / output terminal 15 to the coupling electrode 12
It is connected to a and is bonded to the bonding substrate 12. Also, terminals 16 are connected to both ends of the combined substrate 12, and the dielectric filter 10 is connected by these terminals 16.
I / O terminals are configured.

[0004]

The above-mentioned conventional dielectric filter 10 includes a dielectric coaxial resonator 11, an input / output terminal 15 of the dielectric coaxial resonator 11, a coupling substrate 12, and an input / output terminal of the dielectric filter 10. Since it is composed of a large number of parts such as 16 and cases 14 and 14 ', the cost is disadvantageous and the assembly process is complicated.

Further, since the shapes and sizes of the respective parts are different, it is difficult to mechanically perform each assembling work, and it is also difficult to automate the manufacturing process.

The present invention has been made in view of the above problems, and an object thereof is to provide a dielectric filter having a simple structure and capable of automating the manufacturing process.

[0007]

In order to solve the above-mentioned problems, the invention according to claim 1 is characterized in that one side face is provided with one recessed groove in the axial direction, and the outer circumference except for this side face and one end face. A first filter component member whose surface and the groove are covered with a conductive material; an outer conductor portion to which the side face and the other end face of the first filter component member are connected; An electrode including a coupling circuit portion for coupling between the conductor portion and the inner conductor portion and an input / output terminal portion is provided at a predetermined position on the front and back surfaces and side surfaces of the substrate; By combining the first and second filter constituent members, a filter circuit formed by vertically connecting a plurality of dielectric coaxial resonators is configured.

In the invention according to claim 2, at least two recessed grooves are provided on one side surface at predetermined intervals in the axial direction, and the outer peripheral surface excluding this side surface and one end surface and the recessed groove. And a plurality of inner conductor portions to which the concave groove is connected and an outer conductor portion to which the side surface and the other end surface of the first filter constituent member are connected A second filter component member having electrodes formed of terminal portions formed at predetermined positions on the front and back surfaces and side faces of the substrate, and a plurality of dielectric coaxial members by combining the first and second filter component members. The filter circuit is formed by vertically connecting the resonators.

[0009]

According to the first aspect of the present invention, the dielectric filter is assembled by connecting the first filter constituent member and the second filter constituent member.

The side surface and the other end surface of the first filter component are formed on the outer conductor of the electrode formed on the surface of the second filter component, and the first conductor is formed on the inner conductor of the electrode.
Each of the dielectric coaxial resonators that are the constituent elements of the filter circuit is formed by connecting the concave grooves of the filter constituent member, and these dielectric coaxial resonators are vertically connected by the coupling circuit portion of the electrodes. , A dielectric filter is constructed.

According to the invention described in claim 2, the first
A dielectric filter is formed by integrally coupling a plurality of dielectric coaxial resonators by coupling the filter component and the second filter component.

[0012]

1 is an exploded perspective view showing an embodiment of the structure of a dielectric filter according to the present invention.

A dielectric filter 1 shown in FIG. 1 is a combination of a resonator constituent member 2 (first filter constituent member) forming a part of a dielectric coaxial resonator, and the resonator constituent member 2 in combination. A base substrate 3 (second filter component member) that constitutes a dielectric coaxial resonator, and couples a plurality of dielectric coaxial resonators to each other to configure an internal unit 8 of the dielectric filter 1, and the base substrate. 3 and the cover 4 for protecting the surface 31 side and for grounding the case.

The resonator constituent member 2 is a dielectric member 21 made of ceramics or the like and having a U-shaped cross section and having a predetermined outer peripheral surface coated with a conductive material 5. That is, FIG.
As shown in, the one side surface 21a and one end surface 21e of the prism-shaped dielectric body 21 in which one groove 22 is bored at a predetermined depth along the axial direction at the substantially center of the one side surface 21a. Side surfaces 21b to 21d to be excluded, the other end surface 21f and the groove 22
Is coated with a conductive paste such as silver or copper and baked at a predetermined temperature to form the conductor film 5.

The resonator component 2 corresponds to the upper portion of the dielectric coaxial resonator 6 having a rectangular cross section, which is shown in phantom in the figure, when it is divided into two parts in the axial direction. The dielectric coaxial resonator 6 that constitutes the dielectric filter 1 is configured by being combined with the substrate 3.

Therefore, the conductor film 5 of the side surfaces 21b to 21d constitutes an outer conductor of the dielectric coaxial resonator 6, and the conductor film 5 of the concave groove 22 is an inner conductor of the dielectric coaxial resonator 6. The conductor film 5 on the other end face 21f constitutes a short-circuit conductor that short-circuits the outer conductor 61 and the inner conductor at the end.

In consideration of the mountability between the resonator component 2 and the base substrate 3, preferably, the conductor films 5 on the side surfaces 21b to 21d of the dielectric 21, the groove 22 and the other end surface 21f are formed as shown in FIG. As shown in FIG. 7, it may be formed by wrapping around the one side surface 21a.

The concave groove 22 of the dielectric component member 2 is also provided.
Is not limited to a U-shape, but may be a V-shape or a semi-circle shape as shown in FIGS. 4 and 5, for example.

The base substrate 3 is made of the same material as the resonator component 2 and has a thickness substantially the same as that of the lower portion 61 of the dielectric coaxial resonator 6.

On the surface 31 of the base substrate 3, as shown in the plan view of FIG.
21d is connected to the conductor film 5 and the dielectric coaxial resonator 6 is connected.
Adjacent to an outer conductor portion 32a constituting an outer conductor of the resonator, and an inner conductor portion 32b connected to the conductor film 5 of the concave groove 22 of the resonator constituting member 2 to form an inner conductor of the dielectric coaxial resonator 6. An electrode 32 including a coupling circuit portion 32c for capacitively coupling the dielectric coaxial resonator 6 is formed.

One end of the inner conductor portion 32b is connected to the outer conductor portion 32a, and when the resonator constituting member 2 is attached to the base substrate 3, it constitutes a coaxial resonator having a short-circuit termination. There is.

The other end of the inner conductor portion 32b is connected to each land 33 of the coupling circuit portion 32c. A predetermined gap 7 is provided between the lands 33, and the adjacent dielectric coaxial resonators 6 are electrically coupled via the capacitance formed by the gap 7.

On the back surface of the base substrate 3, as shown in FIG.
As shown in (AA cross-sectional view of FIG. 6), a ground conductor 35 is formed, and the outer conductor portion 32 a has a plurality of through holes 34.
Is connected to the ground conductor 35. When the resonator component 2 is attached to the base substrate 3,
The conductor film 5 on the side surfaces 21b to 21d of the resonator component 2 is connected to the ground conductor 35 through the through hole 34, and the conductor film 5, the through hole 34, and the ground conductor 3 are connected.
The outer conductor of the dielectric coaxial resonator 6 is constituted by 5.

Also, on the side surface of the base substrate 3, FIG.
As shown in the side view of FIG. 3, side electrodes 36 for connecting the outer conductor portion 32a and the ground conductor 35 on the back surface are provided, and electrodes 37 as input / output terminals of the dielectric filter 1 extend the coupling circuit portion 32c. Is formed. The shaded portion in the figure is the portion where the conductor film 5 is formed.

If necessary, a lead terminal may be connected instead of the electrode 37, and the input / output terminal may be provided so as to project from the body of the dielectric filter 1.

With the above structure, as shown in FIG. 1, the resonator component 2 is placed on the surface of the base substrate 3 with the concave groove 22 facing the inner conductor portion 32b of the electrode 32, and the resonator is The conductor film 5 on the side surfaces 21b to 21d of the constituent member 2 and the outer conductor portion 32a of the base substrate 3 are connected to each other, and the conductor film 5 of the groove 22 and the inner conductor portion 32b of the base substrate 3 are connected to each other to form a dielectric. Each dielectric coaxial resonator 6 that constitutes the filter 1 is completed, and the internal unit 8 of the dielectric filter 1 in which these dielectric coaxial resonators 6 are coupled to each other is assembled. In addition, the resonator component 2
Is connected to the base substrate 3 by using, for example, soldering or a conductive paste.

In the dielectric filter 1, the inner unit 8 is covered with the cover 4 so as to cover the resonator constituting member 2.
Is attached and completed.

As described above, a dielectric filter 1 is formed by vertically connecting the dielectric coaxial resonators 6 by combining the resonator component 2 forming a part of the dielectric coaxial resonator 6 and the base substrate 3. Since the internal unit 8 is configured, the number of parts and the number of assembling steps can be reduced.

Further, the internal unit 8 is constructed only by placing the resonator forming member 2 at a predetermined position on the base substrate 3 and connecting the resonator forming member 2, and further the internal unit 8 is formed.
Since the dielectric filter 1 is completed by covering the cover 4 with the cover 4, the dielectric filter 1 can be assembled by a simple operation, and the assembly process can be automated.

FIG. 9 is a front view showing another embodiment of the structure of the dielectric filter according to the present invention. In this embodiment, a dielectric filter 1 using a dielectric coaxial resonator formed by integrally molding a plurality of dielectric coaxial resonators is constructed in the same manner as described above.

Therefore, the resonator constituent member 2'corresponds to the upper portion of the dielectric coaxial resonator 6'in which a plurality of (here, three) dielectric coaxial resonators shown in FIG. 10 are integrally molded. Is becoming That is, the resonator component 2'is a dielectric body in which one side surface 21a 'is provided with a predetermined interval and three concave grooves 22' are bored at a predetermined depth along the axial direction (direction B in the drawing). 21, one side surface 21a 'and one end surface 21e'
The conductive film 5 is formed by applying a conductive paste such as silver or copper to the side surfaces 21b 'to 21d' other than and the other end surface 21f 'and the concave groove 22' and firing the paste at a predetermined temperature.

On the other hand, on the front and back surfaces of the base substrate 3 ', as described above, the electrodes including the outer conductor portion, the inner conductor portion and the input / output terminal portion are formed. In the case of a dielectric coaxial resonator formed by integrally molding a plurality of dielectric coaxial resonators, the dielectric coaxial resonators are magnetically coupled to each other by a magnetic field component in the dielectric 21 ', and No electrode corresponding to the coupling circuit portion 32c is provided on the electrode of the substrate 3 '.

Then, as shown in FIG. 9, the internal unit 8'is assembled by mounting the resonator constituting member 2'at a predetermined position on the surface of the base substrate 3 '.

[0034]

As described above, according to the present invention,
Since the dielectric filter is constituted by the first filter constituent member which constitutes a part of the dielectric coaxial resonator and the second filter constituent member which is combined with the first filter constituent member to form the filter circuit. The number of constituent parts and the number of assembling steps are reduced, and the cost can be reduced.

Further, the assembling work is simplified and the assembling process can be automated.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of the structure of a dielectric filter according to the present invention.

FIG. 2 is a perspective view showing a structure of a resonator constituent member.

FIG. 3 is a front view showing the structure of a resonator constituent member.

FIG. 4 is a front view showing the structure of a second embodiment of the resonator constituting member.

FIG. 5 is a front view showing the structure of a third embodiment of the resonator constituting member.

FIG. 6 is a plan view of a base substrate.

7 is a cross-sectional view taken along the line AA of FIG.

FIG. 8 is a side view of the dielectric filter according to the present invention.

FIG. 9 is a front view showing another structure of the dielectric filter according to the present invention.

FIG. 10 is a perspective view showing a structure of a resonator constituting member applied to the dielectric filter.

FIG. 11 is an exploded perspective view showing the structure of a conventional dielectric filter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Dielectric filter 2,2 'Resonator constituent member (first filter constituent member) 3,3' Base substrate (Second filter constituent member) 4 Cover 5 Conductive material 6 Dielectric coaxial resonator 7 Gap 8,8 ′ Internal unit 31 Surface 32 Electrode 33 Land 34 Through hole 35 Grounding conductor 36, 37 Side electrode

Claims (2)

[Claims] 1. A first filter component member in which one groove is formed in one side surface in the axial direction, and the outer peripheral surface excluding this side surface and one end surface and the groove are covered with a conductive material, An outer conductor portion to which the side surface and the other end surface of the first filter component member are connected, a plurality of inner conductor portions to which the concave groove is connected, a coupling circuit portion for coupling the inner conductor portions, and an input / output terminal portion. And a second filter component formed on the front and back surfaces and side faces of the substrate at predetermined positions, and a plurality of dielectric coaxial resonators are formed by combining the first and second filter components. A dielectric filter comprising a filter circuit formed by cascade connection. 2. At least two recessed grooves are provided on one side surface at predetermined intervals in the axial direction, and the outer peripheral surface excluding this side surface and one end surface and the recessed groove are covered with a conductive material. 1
Of the substrate, the electrode including the filter constituent member, the outer conductor portion to which the side surface and the other end surface of the first filter constituent member are connected, the plurality of inner conductor portions to which the concave groove is connected, and the input / output terminal portion. Second formed on the front and back surfaces and side surfaces at predetermined positions
And a filter circuit formed by vertically connecting a plurality of dielectric coaxial resonators by combining the first and second filter constituent members. ..