JPH03250903A - Manufacture of dielectric resonator - Google Patents

Abstract

PURPOSE:To easily and stably connect a coupling capacitor to an inner conductor film under the condition of no use of solder or less quantity of use of solder by inserting at least part of the coupling capacitor to a throughhole for resonance, bending a projection of a connection member simultaneously so as to be in elastic contact with an inner conductor film. CONSTITUTION:In order to couple 2nd electrodes 16, 17 of coupling capacitors 10, 11 to an inner conductor film with lead terminals 24, 25, a connection member 26 having a circular center part 32 made of a metallic plate with elasticity such as a phosphorous bronze having a thickness of 0.05mm whose diameter is 2.5mm and four fin-shaped or wing-shaped projections 34 projecting from an outer circumferential ridge 33 is prepared. In the connection members 26, 27, the 1st and 2nd coupling capacitors 10, 11 are engaged with the 2nd lead terminals 24, 25 before being inserted through a throughhole 4. Then the assembly is fitted to the throughhole 4 from a 1st end face 2 of the dielectric block 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a dielectric resonator for use in communication equipment such as, for example, car telephones, personal radios, and cordless telephones.

[Prior Art] A 1/4 wavelength distributed constant dielectric resonator for use in communication equipment, etc. includes a dielectric block having one or more resonance through holes, and a dielectric block having one or more resonance through holes. The device consists of an inner conductor film provided, an outer conductor film provided on the outer peripheral surface of the dielectric block, and a coupling capacitor connected to the inner conductor film.
For example, it is disclosed in Japanese Patent Application Laid-Open No. 1-181203.

[Problems to be Solved by the Invention] Incidentally, since the electrodes of the coupling capacitor and the inner conductor film are connected within the resonance through-hole, it has been difficult to achieve a robust and reliable connection between the two. Furthermore, when the two are bonded together with solder, microcracks may occur in the ceramic dielectric block due to thermal shock caused by the heat of the solder, which may cause characteristic fluctuations.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for manufacturing a dielectric resonator that can stably and easily connect a coupling capacitor to an inner conductor film without using solder or using a small amount of solder.

[Means for Solving the Problems] To achieve the above object, the present invention will be described with reference to the reference numerals in the drawings showing the embodiments. a dielectric block 1 having an outer circumferential surface 7 between and one or more resonance through holes 4 extending from the first end surface 2 to the second end surface 3; and a wall surface of the through hole 4. an inner conductor film 6 provided on the outer peripheral surface 7 of the dielectric block 1, an outer conductor film 8 provided on the outer peripheral surface 7 of the dielectric block 1, and first and second lead terminals 20, 24, A terminal 20 is led out to the first end surface 2 side of the dielectric block 1, and the second lead terminal 24 is connected to the inner conductor film 6 of the through hole 4 via a connecting member 26. In the method for manufacturing a dielectric resonator, the coupling capacitor 10 and a portion 29d for limiting the insertion depth of the coupling capacitor 10 into the through hole 4 are integrated into the coupling capacitor 10. a step of preparing the first
a central portion 32 having a size that can be inserted into the inner conductor film 6 of the through hole 4 at the end surface 2 of the through hole 4; a plurality of protrusions 34,
a step of preparing a conductive connecting member 26 provided with a notch 35 into which the second lead terminal 24 can be press-fitted or engaged in the central portion 32;
By inserting the second lead terminal 24 into the notch 35, an electrical and mechanical connection is established between the connecting member 26 and the second lead terminal 24, and the limiting portion 29d is connected to the dielectric At least a portion of the coupling capacitor 10 is inserted into the through hole 4 so as to come into contact with the first end surface 2 of the body block 1, and at the same time, the protruding portion 33 of the connecting member 26 is bent to close the inner conductor film. 6. The present invention relates to a method for manufacturing a dielectric resonator characterized by comprising a step of bringing the dielectric resonator into elastic contact with the dielectric resonator.

[Function] According to the present invention, the coupling capacitor 10 and the connecting member 2
6 into the through hole 4, the second lead terminal 24
Electrical connection between the inner conductor film 6 and the inner conductor film 6 is achieved. Therefore, this connection becomes extremely easy.

Embodiment Next, a dielectric filter including a 1/4 wavelength distribution constant type dielectric resonator according to an embodiment of the present invention will be described with reference to FIGS. 1 to 9.

This dielectric filter is made of barium titanate porcelain. Oms prismatic dielectric block 1
It is equipped with The dielectric block 1 is provided with two circular resonance through holes 4 and one coupling through hole 5 with a diameter of 2.7H extending from the first end surface 2 to the second end surface 3. An inner conductor film 6 is provided on the wall surface of each resonance through hole 4, an outer conductor film 8 is provided on the outer peripheral surface 7 between the pair of end surfaces 2. An end conductor film 9 is provided to connect the inner conductor film 6 and the outer conductor film 7. The inner conductor film 6, the outer conductor film 8, and the end face conductor film 9 are made of silver paste coated and baked, and have a film thickness of 10 μm. Note that the other end surface 2 is an open end surface.

The axial lead type II and second coupling capacitors 10.11, which are respectively disposed so as to be partially inserted into each resonance through hole 4, are connected to the respective cylindrical capacitor ceramic dielectrics 12.13. , a respective first electrode 14.15 provided near one end of each dielectric 12.13, and a respective second electrode 16.17 provided in a region near the other end; The electrodes 14.15 and the second electrodes 16.17 are formed so as to provide a capacitance between them.

A respective first lead terminal 20.21 is connected to one electrode 14.15 of each coupling capacitor 10, 11 via a metal cap 18.19.

The second electrodes 16.17 are also respectively covered with metal caps 23.24, and respective second lead terminals 24.25 are led out. Each lead terminal 20.21.24.25 consists of a lead wire with a diameter of 0.55 mm.

Connection members 26 and 27 are arranged between the second lead terminals 24 and 25 in the resonance through-hole 4 and the inner conductor film 6, respectively.

The first and second coupling capacitors 10, 11 and the metal shield member 28 are integrated by a common insulating support 29 made of thermoplastic synthetic resin. This integration is performed before placing the first and second coupling capacitors 10.11 in the resonance through hole 4. That is, as shown in FIG. 5 and FIG.
9 to obtain an assembly 30.

The shield member 28 is made of a phosphor bronze plate with a thickness of 0.2 mm and soldered, and includes an upper surface portion 28a that covers the upper part of the coupling through hole 5 and the vicinity of the resonance through hole 6, and A pair of side surfaces 28b and 28c for connection to the outer conductor membrane 8 on the longitudinal pair of sides, and four protrusions 28d for attachment to a circuit board (not shown) and for connection to ground. The upper surface part 28a
is fixed to the insulating support 29.

The insulating support 29 connects the first and second coupling capacitors 10.
11 connecting portions 29a, protrusions 29b and 29c for achieving radial positioning of the first and second coupling capacitors 10.11 with respect to the resonance through hole 6, and first and second coupling capacitors 10.11 with respect to the resonance through hole 6. Second coupling capacitor 10.11
Flange portions 29d, 2 for achieving positioning in the depth direction of
9e, and functions as a position limiter. In addition, the first
and the second coupling capacitor 10.11 is connected to the lead terminal 2.
0.21.24.25 and metal cap 18.19.22
．． 23 is covered with an insulating support 29.

When assembling the dielectric filter shown in FIGS. 1 to 3, a dielectric block 1 provided with each conductor film 6, 8, and 9 shown in FIG. 4 is prepared, and a dielectric block 1 shown in FIGS. 5 and 6 is prepared. An assembly 30 of the coupling capacitor 10.11 and the shield member 28 is prepared. Since the dimensions and mutual spacing of the protrusions 29b and 29c surrounding the first and second coupling capacitors 10.11 of the insulating support 29 are determined to fit the resonance through hole 4, the protrusions 29b, 29C can be coaxially fitted into each resonance through hole 4.

Further, the depth of insertion of the protrusions 29b and 29c is the flange 29d.
, 29e are in contact with the upper surface of the dielectric block 1.

The pair of side surfaces 28b, 28C of the shielding member 28 are determined to approximately match the distance between the side surfaces of the outer conductor film 8 of the dielectric block 1, so the pair of side surfaces 28b, 28C
The state shown in FIG. 3 in which the opposing side surfaces of the outer conductor film 8 of the dielectric block 1 are sandwiched at c can be easily obtained. Since the shield member 28 is formed of a slightly elastically deformable metal plate, even if the opposing distance between the side surfaces 28b and 28c is slightly smaller than the width of the dielectric block 1, mounting can be easily achieved. You can. In order to ensure electrical and mechanical connection of the shield member 28 to the outer conductor film 8, the two are connected by solder 31, which is shown in principle in FIG.

In order to connect the second electrode 16.17 of the coupling capacitor 10.11 to the inner conductor membrane 6 by means of the lead terminal 24.25, a connecting member 26 shown in FIGS. 7 and 8 is prepared.

This connecting member 26 is made of a metal plate having spring properties such as phosphor bronze with a thickness of 0.05 mm, and has a diameter of 2.5 g.
It has a +m circular center portion 32 and four fin or wing-shaped protrusions 34 protruding from this outer peripheral edge 33. Central part 3
2 has a width of 0.2 as and a length of 1 formed radially in the center.
A cutout portion 35 is provided which is a group of a plurality of slits of ゜O■. As a result, a plurality of acute angle portions 36 protruding toward the center are formed in the central portion 32. The diameter of the inscribed circle with respect to the tips of the plurality of acute angle portions 36 is somewhat smaller than the diameter of the second lead terminal 24. The diameter of the central portion 32 is approximately the same as or somewhat smaller than the diameter of the resonance through hole 4 provided with the inner conductor film 6. Projections 34 arranged in four directions at 90 degree intervals
is formed with a width of 0.51 layers and a length of 0.7 layers, and has a length that protrudes from the resonance through hole 4 when the connecting member 26 shown in FIG. 7 is arranged coaxially with the resonance through hole 4. It has a certain quality. Note that the second connecting member 27 for the second coupling capacitor 11 is formed exactly the same as the first connecting member 26.

The connecting member 26.27 is engaged with the second lead terminal 24.25 as shown in FIG. 6 before inserting the first and second coupling capacitor 10.11 into the through hole 4. That is, the second lead terminal 24 is press-fitted into the notch 35 of the connecting member 26. As a result, the acute angle portion 36 is pushed apart, and the acute angle portion 36 comes into elastic contact with the second lead terminal 24 . When the connecting member 26 is pushed in until it contacts the metal cap 22, the connecting member 26 is firmly electrically and mechanically coupled to the second lead terminal 24 at the acute angle portion 36.

Note that the second connecting member 27 is also engaged with the second lead terminal 25 in the same manner as the first connecting member 26 .

Next, the assembly shown in FIG. 6 is fitted into the through hole 4 of the dielectric block 1 from the first end surface 2 side. That is, the second lead terminals 24, 25 are inserted into the through holes 4, and the assembly 30 is pressed from the first end surface 2 toward the second end surface 3. Since the fin-shaped or wing-shaped protrusion 34 protrudes from the resonance through hole 4, its tip is pressed and bent into an L shape so as to face the first end surface 2 side, and comes into elastic contact with the inner conductor film 6. while entering the inside of the resonance through hole 4. When the connection member 26 is continued to be pushed in, the flanges 29d, 29 of the insulating support 29
e comes into contact with the first end surface 2, and further pushing is prevented. The bent protrusion 34 is elastically connected to the inner conductor film 6, and an electrical connection is established. The pushing of the second connecting member 27 into the resonance through hole 4 is also done by the first connecting member 26.
Do exactly the same thing.

The protrusions 29b and 29c of the insulating support 29 are press-fitted into the resonance through hole 4, and the pair of side surfaces 2 of the shield member 28
8b and 28c have elasticity and are pressed against the outer conductor film 8, and the connecting members 26.27 are engaged with the second lead terminals 24.25, so that the first and second coupling capacitors 10
．． The assembly 30 including the dielectric block 11 is relatively firmly integrated with the dielectric block 1. However, in order to bond more firmly, in this embodiment, the shield member 28 is bonded to the outer conductor film 8 with solder 31.

In the completed dielectric filter, for example, the input and output lead terminals 20.21 and the protrusion 28d of the shield member 28 are inserted into a through hole of a circuit board (not shown), and the input and output lead terminals 20.21 are used for signal transmission. At the same time, the shield member 28 is connected to the ground.

FIG. 9 shows an equivalent circuit of a dielectric filter. The first resonant circuit consisting of the capacitor C1 and the inductance LL is based on the inner conductor film 6 of one of the pair of through holes 4, the grounded outer conductor film 8, the end surface conductor film 9, and the dielectric block 1. A second resonant circuit that is formed and includes a capacitor C2 and an inductance L2 is formed by connecting the other inner conductor film 6 of the pair of through holes 4, the grounded outer conductor film 8, the end surface conductor film 9, and the dielectric block 1. The two resonant circuits are coupled by a dielectric impedance Z1.

According to this embodiment, simply pushing the connecting members 26, 27 together with the coupling capacitors 10, 11 into the resonance through hole 6,
Since the connection between the coupling capacitor 10.11 and the inner conductor film 6 is achieved, this connection becomes easy.

Further, since the above connection can be achieved without using solder, the problem of microcracking due to thermal shock during soldering does not occur.

In addition, since the first and second coupling capacitors 10.11 are supported by the insulating support 29 and the flange portions 29d129e are provided there, this functions as a stopper and prevents the resonance of the first and second capacitors 10.11. The positioning of the through-hole 4 in the depth direction is achieved, and the embedded position of the connecting member 26, 27 becomes constant.

[Modifications] The present invention is not limited to the above-described embodiments, and, for example, the following modifications are possible.

(1) The present invention can also be applied to a dielectric resonator in which the dielectric block 1 has only one resonance through hole 4. That is, the present invention can be applied even when forming only one resonant circuit.

When configuring only one resonant circuit, the dielectric block is usually formed in a cylindrical shape.

(2) Three or more resonance through holes 4 in the dielectric block 1
The present invention can also be applied to a case where a multi-stage dielectric filter is configured.

(3) A 1/2 wavelength dielectric resonator or filter can be formed by omitting the end face conductor film 9.

(4) The dielectrics 12.13 of the first and second coupling capacitors 10.11 can be cylindrical.

(5) A circular hole is formed as a notch 35 at the center of the central portion 32 of the connecting member 26, 27, a plurality of grooves are provided radially extending from this hole, and the second lead terminal 24 is inserted into this hole. It may be press-fitted or fitted.

(6) The connecting members 26, 27 may be bonded to one or more of the inner conductor membrane 6, the lead terminals 24, 25, and the metal caps 18, 19 with a small amount of solder.

Even if solder is used in combination, there is no need to increase the amount of solder because the connecting members 26 and 27 have spring properties and are in firm contact. If the amount of solder is small, the thermal shock will be small.

(7) Coaxially position the connecting members 26 and 27 in the through hole 4 on the first end surface 2, and insert the second
While inserting the lead terminals 24.25 of and the first and second coupling capacitors 10.11 into the through hole 4,
The lead terminals 24.25 may be engaged with the connecting members 26.27. In this case, it is convenient to provide the connecting members 26, 27 with projections for positioning with respect to the through hole 4.

[Effects of the Invention] As is clear from the above, according to the present invention, the connection between the coupling capacitor and the inner conductor film can be easily and reliably achieved.

[Brief explanation of drawings]

FIG. 1 shows a second dielectric filter according to an embodiment of the present invention.
Figure 2 is a plan view of the dielectric filter shown in Figure 1, Figure 3 is a cross-sectional view taken along line ■-■ in Figure 2, Figure 4 is a cross-sectional view of the dielectric filter shown in Figure 1. A perspective view of a dielectric block having a conductive film, FIG. 5 is a plan view showing an assembly for configuring the dielectric filter of FIG. 1, and FIG. 6 is a perspective view of the assembly shown in FIG. 7 is a plan view showing the connection member before attachment, FIG. 8 is a front view of the connection member shown in FIG. 17, and FIG. 9 is an equivalent circuit diagram of the dielectric filter shown in FIG. 1. 1... Dielectric block, 2... First end surface, 3...
- Second end surface, 4... Resonance through hole, 6... Inner conductor film, 7... Outer peripheral surface, 8... Outer conductor film, 10... First coupling capacitor, 11. ...Second coupling capacitor, 20.21...First lead terminal, 24.25.
...Second lead terminal, 26...First connection member, 2
7... Second connection member, 28... Shield member, 2
9... Insulating support body, 32... Center part, 34... Projection part, 35... Notch part. Agent Nori Takano Figure 1 Figure 5 Figure 6

Claims (1)

[Claims] [1] Having first and second end surfaces (2) and (3) facing each other and an outer circumferential surface (7) between them, and from the first end surface (2) A dielectric block (1) having one or more resonance through holes (4) reaching the second end surface (3), and an inner conductor film (6) provided on the wall of the through hole (4). and an outer conductor film (8) provided on the outer circumferential surface (7) of the dielectric block (1), and first and second lead terminals (20) and (24), and the first A lead terminal (20) is connected to the dielectric block (1).
) is led out to the first end surface (2) side, and the second lead terminal (24) is connected to the inner conductor film (6) of the through hole (4) via the connecting member (26). A method for manufacturing a dielectric resonator comprising a coupling capacitor (10) connected to the coupling capacitor (10).
0) of integrating a portion (29d) into the coupling capacitor (10) for limiting the insertion depth into the through hole (4); a central portion (
32), and a plurality of protrusions (34) that protrude outward from the center part (32) and are bendable so as to protrude from the through hole (4),
2) preparing a conductive connecting member (26) provided with a notch (35) into which the second lead terminal (24) can be press-fitted or engaged; ) in the notch (35) of the second
By inserting the lead terminal (24) of the connecting member (26) and the second lead terminal (24), an electrical and mechanical connection is established between the connecting member (26) and the second lead terminal (24), and the limiting portion (2
9d) is the first end surface (
2), at least a portion of the coupling capacitor (10) is inserted into the through hole (4) so as to be in contact with the inner conductor film. (6) A method for manufacturing a dielectric resonator, comprising the step of bringing the material into elastic contact with the material.