JPS60137102A - Dielectric filter - Google Patents

Abstract

PURPOSE:To obtain a small-sized, lightweight dielectric filter of stable quality which is manufactured and assembled easily by providing spacers to the lower end part of a main housing body, and short-circuiting lower end parts of dielectric coaxial resonance elements to tops of the spacers. CONSTITUTION:Spacers 41a-41c made of metal are provided at the lower part of the main housing body 1 where dielectric coaxial resonance elements 2a- 2c are installed. Then short-circuit surfaces of the dielectric coaxial resonance elements 2a-2c are coated with fixing agents 42a-42c such as cream solder and adhered to the spacers 41a-41c, and the whole block is mounted inside of the main housing body 1. Consequently, the small-sized, lightweight dielectric filter of stable quality whick is manufactured and assembled easily is obtained.

Description

[Detailed description of the invention] Industrial applications The misfire ryll is related to dielectric filters.

Structure of a conventional example and its problems A conventional dielectric filter will be explained below with reference to all the drawings.

Fig. 1 is a sectional view of a dielectric filter consisting of three stages of dielectric coaxial resonant elements in a sheet metal case, which is considered as a conventional example, Fig. 2 is a sectional view taken along line A-1 in Fig. 1, and Fig. 3 is a dielectric filter. FIG. 3 shows a perspective view of a coaxial resonant element.

In Figures 1, 2, and 3, 1 is the housing body;
It is constructed by bending thin sheet metal.

2a, 2b, and 20 are dielectric coaxial resonant elements as shown in Fig. 3, in particular, 2a is the input side dielectric coaxial resonant element, and 2C is the output side dielectric coaxial resonant element, which is longer than the dielectric coaxial resonant element 2b at the crotch. is getting shorter. This is because the coupling capacitance between the dielectric coaxial resonant element 22L on the input side and the dielectric coaxial resonant element 2C on the output side is larger than that of the dielectric coaxial resonant element 2b between the legs, so changing the length can change the coupling capacitance. The resonant frequency fo is matched. 3 is an inner conductor, 4 is an outer conductor, and the surface of the dielectric 5 is coated with a highly conductive paste or copper plating. Reference numeral 6 denotes a coupling substrate, in which appropriate electrical coupling between adjacent dielectric coaxial resonant elements is achieved using a capacitance formed on the dielectric substrate.

7a, 7b, To are central conductors made of metal, and a fixing agent 8N, sb, sc, such as cream solder or conductive paste, is applied to the inner conductor 3 of each dielectric resonant element together with the bonding substrate 6.
is fixed.

9a and 9b are fixing agents such as cream solder or conductive paste that fix the dielectric coaxial resonant elements 2a, 2b, and 2C to the housing body 1 and the side plate 10 made of a metal plate. 11
Reference numerals a', 11b, and 11c are tuning screes made of metal, which are attached to the tuning screw 12 made of metal to adjust the frequency of each resonant element. 13a is an input side connector, and 13b is an output side connector. Reference numeral 14 denotes a bent portion at the lower end of the housing body 1, which is bent with an appropriate bending radius. A method for manufacturing the dielectric filter configured as described above will be described below.

Inside of Ushizu housing body 1 and dielectric coaxial resonant elements 2a, 2b
, 2C, apply a fixing agent 9a such as cream or conductive paste to the area where 2C contacts. Next, a fixing agent sa, '8b, 8c such as cream solder or conductive paste is applied to the inner conductor 3 of the dielectric coaxial resonant elements 2&, 2b, 2C. Next, the center conductor 7 is inserted into the hole of the coupling board 6 corresponding to the center of each dielectric coaxial resonant element 2a, 2b, 2G.
Attach the tips of a, 7b, and 7C (the one with the smaller outer diameter),
Further, dielectric coaxial resonant elements 2a, 2b, 2 are disposed at the tip of the dielectric coaxial resonant elements 2a, 2b, 2.
After mounting the blocks in the order of 0 so that the surface of the dielectric 3 faces the bonding substrate 6, the entire blocks are mounted inside the casing body 1. Next, dielectric coaxial resonant elements 2a, 2'b, 2
A fixing agent 9b such as cream solder or conductive paste is applied to the dielectric coaxial resonant element side of the surface where cm and the side plate 10 are in contact with each other. Next, after attaching the side plate 10, the whole is fixed by heating in a furnace. Next, after fixing the input side connector 13a and the output side connector 13b to the side surface of the open end of the housing body 1 with half lIl, etc., the input side connector 13a and the output side connector 13
Connect the tip terminal of b to each terminal on the input/output side of the joint JiV board 6. Next is the tuning screen v--112L.

11b and 11C on the tuning screw plate 12, attach the tuning screw plate 12 to the housing body 1.
Attach to the open end of the A dielectric filter can be formed relatively easily by fixing by soldering, conductive paste, or screws. However, in the above configuration, the length of the dielectric coaxial resonant elements 2a, 20 on the input side and the output side is shorter than that of the dielectric coaxial resonant element 2b in the crotch, so that the coupling board 6 tends to bend. The center conductors 7'a and 7b are in the deformed state.

By the completion C, each dielectric coaxial resonant element is attached to the surface of the dielectric 5. In such a state, troubles such as damage to the bonding substrate 6 and peeling off of the thin copper of the bonding pattern formed on the surface of the bonding substrate occur, leading to a decrease in productivity. Further, the dielectric coaxial resonant element 2a is attached to the shoulder of the bent portion 14 at the lower end of the housing body 1.

2b and 20 ride up, and the shape of the casing body 1 becomes wider from the two ends to the bottom end, resulting in unacceptable dimensional errors during manufacturing, resulting in a lower yield. Moreover, it has the disadvantage that it is unsightly in shape and difficult to install in equipment.

OBJECTS OF THE INVENTION The present invention overcomes the above-mentioned drawbacks of the prior art, and aims to provide a small and lightweight dielectric filter that is easy to manufacture and assemble and has stable quality.

Structure of the Invention In order to achieve the above object, the present invention provides a spacer at the lower end of the housing body, and makes the length of each dielectric coaxial resonant element including the spacer the same, so that the dielectric coaxial resonator on the bonding board mounting surface This eliminates the step difference in the resonant element.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 4 is a cross section of a dielectric filter composed of three stages of dielectric coaxial resonant elements according to an embodiment of the present invention, and FIG.
It shows a cross section taken along line A-A' in the figure.

This embodiment differs from the conventional configuration shown in FIGS. 1 to 3 in that a metal spacer 411L is provided at the bottom of the housing body 1 in which the dielectric coaxial resonant elements 8a to 8C are installed.
-41C was provided. The spacers 41a to 410 may have any shape such as a disk or a ring. spacer 41a,
41 (minimum plate thickness of t, input/output dielectric coaxial resonant element 2
a, the bending radius of the bending portion 14 at the lower end of the housing body 1 is added to the length difference between the dielectric coaxial resonant element 2b between the stage 20 and the stage. '-1: The minimum thickness of the spacer 4b may be the bending radius of the bending portion 14 of the lower portion 17iAH of the housing body 1.

These spacers are dielectric coaxial/resonant elements 2a.

A fixing agent 42 such as cream el'I soil 1 is applied to the surface of the spacers 41a, 41b, 4.
1c, the entire block is mounted inside the housing body 1.

According to the above configuration, the spacer 41 is provided at the lower end of the dielectric coaxial resonant elements 2a, 2b, 20 having different lengths.
A dielectric coaxial resonant element 2a including these spacers can be obtained by simply providing spacers a, 41b, and 41c.

2b, 2Q can be made the same, as shown in FIG.
By aligning the surfaces, troubles such as damage due to deformation of the bonding substrate 6 and peeling of the copper plate pattern provided on the bonding substrate can be prevented, and the clamps can be set in the opposite directions during production. Furthermore, spacer 4
By providing 1a, 41b, and 41C, the housing body 1
dielectric coaxial resonant element 2a to the bent part 14 of the lower part of
, 2b, and 20 can be prevented from running over each other, making it possible to provide a small and lightweight dielectric filter that is dimensionally stable.

Effects of the Invention As described above, the present invention provides a spacer at the bottom, il, and H portions of the casing body, and short-circuits the lower end of the dielectric coaxial resonant element on the spacer. You can reduce troubles and produce products with stable quality, and the effects are incredible.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventionally considered electrically transparent filter;
The figures are a sectional view taken along the line A' in FIG. 1, FIG. 3 is a perspective view of a dielectric coaxial resonant element, FIG. FIG. 4 is a cross-sectional view taken along line AA' in FIG. 4; 1--Housing body, 21L, 2b, 2C--Dielectric coaxial resonant element, 3--Inner conductor, 4--Outer conductor, 5--Dielectric, 6・・・・Bond substrate, 7&
, 7b, 7C...center conductor, sa, sb, sc
, 9a, 9b---fixing agent, 10---side plate, 11
a, 11b, 11c・Turing screw, 12
-・Screw plate, 13! L--Output side connector, 13b--Output side connector, 14- Lower end bent portion, 41a. 41b, 41cm...-spacer, 42a,
42b. 42C--Fixative.

Claims (1)

[Claims] When a housing has at least three or more dielectric coaxial resonant elements and the lower end of the dielectric coaxial resonant element is short-circuited to the lower end of the housing, a spacer is provided at the lower end of the housing, and a spacer is provided at the lower end of the housing. 11+J (a dielectric filter in which the lower end of the vibration element is short-circuited) between the dielectric and the spacer.