JPS6334323Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a coupling structure applied to distributed constant filters and the like.

Conventionally, filters in the several 100 MHz range have used LC resonant circuits or coaxial cavity resonators, but they are structurally unstable or complex, have unsatisfactory characteristics, and require adjustment. There were problems such as it was time-consuming and the cost could not be reduced.

For this purpose, as shown in FIG. 1, two through holes 12 and 13 are provided in the dielectric block 11, and conductive films 14 and 15 are provided on the inner surfaces of these through holes 12 and 13. A conductive film 16 is provided on the side surface, and the conductive films 14 and 15 are provided on the inner surfaces of the through holes 12 and 13, and the dielectric block 1
The conductive film 16 provided on the conductive film 1 and the dielectric block 11 interposed therebetween constitute a pair of resonant units, and the dielectric block 1 between these resonant units
An equivalent circuit as shown in FIG. 2 is provided with a cavity 17 in FIG. There is a distributed constant type filter with .

In Fig. 2 above, 21 is an input terminal, 22 is an output terminal, 23 is an input coupling capacitance, 24 is an output coupling capacitance, and 25 and 26 are 1/4 wavelength resonant circuits shown as lumped constant circuits. It is. Therefore,
The distributed constant filter shown in FIG. 1 is a filter in which quarter-wavelength resonant circuits are inductively coupled to each other, and an external circuit and the quarter-wavelength resonant circuit are capacitively coupled.

By the way, in the distributed constant type filter shown in FIG. 1, an input coupling capacitor is used, in which a mounting member 31 made of a metal cylinder or a conductive paste is connected and fixed to a conductive film 14, and counter electrodes 33 and 34 are formed on a columnar dielectric body 32. 18 of the above-mentioned counter electrodes 33 are connected and fixed to the mounting member 31, while the mounting member 35 is also connected and fixed to the conductive film 15 in the same manner as above, and counter electrodes 37 and 38 are formed on the columnar dielectric body 36. Since the opposing electrode 37 of the capacitor 19 is connected and fixed to the mounting member 35, the work of mounting the input coupling capacitor 18 and the output coupling capacitor 19 is troublesome.

The present invention was made in view of the above-mentioned circumstances regarding high frequency components such as distributed constant filters.

That is, the purpose of this invention is to simplify the electrostatic coupling structure.

The gist of this invention is that a hole is formed in a dielectric material, a conductive film is formed on the inner surface of the hole, and a cylindrical column separate from the dielectric material is formed in a space surrounded by the conductive film. The coupling structure is characterized in that a terminal is present via a dielectric material having protrusions or protrusions on the outer peripheral surface, and the terminal and the conductive film are electrostatically coupled.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

In FIG. 3, 11 is a rectangular parallelepiped dielectric block made of titanium oxide ceramic dielectric;
12 and 13 are through holes, 14 and 15 are conductive films provided on the inner surfaces of these through holes 12 and 13, respectively, 16 is a conductive film provided on at least four sides of the dielectric block 11, and 17 is a cavity, The above is the same as the distributed constant type filter shown in FIG.

In the distributed constant type filter shown in FIG. 3, dielectric units 41 and 41 as shown in FIGS. It is press-fitted.

As shown in FIGS. 4 and 5, the dielectric unit 41 is formed into a substantially cylindrical shape by coating a part of a conductive wire 42 with a diameter of, for example, 0.5 mmφ with a dielectric material such as plastic or titanium oxide. The conductive wire 42 is formed so as to pass through the axial center.
There are four protrusions 4 in the axial direction on the outer peripheral surface of the approximately cylindrical body.
3, 43, 43, 43 are integrally formed at 90° intervals. The holes 12 and 13 of the dielectric block 11 are provided at the rear end of the dielectric unit 41.
A flange portion 44 is provided which is abutted against the periphery of the opening on the side where the conductive film 16 is not formed.

As shown in FIG. 3, the dielectric units 41, 41 have flange portions 44, 44 of the dielectric units 41, 41 inserted into the holes 12, 13 of the dielectric block 11 having conductive films 14, 15 formed on their inner surfaces. The dielectric block 11 is press-fitted until it contacts the dielectric block 11.

By doing as described above, the conductive wires 42, 42 and the conductive films 14, 15 formed on the inner surfaces of the holes 12, 13 of the dielectric block 11 can be connected to the dielectric unit 41,
The input coupling capacitor 18 as shown in FIG.
The output coupling capacitor 19 is no longer necessary.

Therefore, there is no need for troublesome installation work such as the input coupling capacitor 18 and the output coupling capacitor 19. Moreover, if the dielectric units 41, 41 are larger than the holes 12, 13 due to manufacturing errors, it is preferable that the protrusions 43 be cut so that they can be easily press-fitted. Without the protrusions, the entire outer periphery would have to be scraped, which would reduce work efficiency, which is undesirable. The number of protrusions is not limited to four, and may also be a simple protrusion.

The present invention is not limited to the distributed constant filter shown in FIG. 3, but can be widely applied to other high frequency components. For example, in addition to the dielectric coaxial resonator having the above-mentioned structure, a cylindrical dielectric material, or a rectangular cylindrical dielectric material formed by forming a circular through hole in a prismatic column, may have inner and outer surfaces, respectively. The present invention can also be applied to a single dielectric coaxial resonator formed with a conductor film and an outer conductor film. A band rejection filter can be constructed by connecting the terminals of such a single dielectric resonator with a 1/4λ coaxial line.

As is clear from the detailed description above, the present invention has a hole formed in a dielectric, a conductive film formed on the inner surface of the hole, and a space surrounded by the conductive film. Since there is a terminal via a dielectric material which is separate from the dielectric material and has a cylindrical shape and has protrusions or protrusions on the outer circumferential surface, and the terminal and the conductive film are electrostatically coupled, conventional methods There is no need for input coupling capacitors and output coupling capacitors, which are troublesome to install, and the assembly of high frequency components to which the present invention is applied becomes extremely simple, and the cost thereof can be reduced.

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view of a conventional distributed constant filter, Figure 2 is an equivalent circuit diagram of the distributed constant filter shown in Figure 1, and Figure 3 is a vertical cross-section of a distributed constant filter that is an example of the present invention. 4 is a front view of the dielectric unit, and FIG. 5 is a plan view thereof. 11...Dielectric block, 12, 13...
Hole, 14, 15, 16... Conductive film, 17... Cavity, 41... Dielectric unit, 42... Conductive wire, 4
3... protrusion, 44... flange portion.

Claims (1)

[Claims for Utility Model Registration] (1) A hole is formed in a dielectric material, a conductive film is formed on the inner surface of the hole, and a space other than the dielectric material is formed in a space surrounded by the conductive film. 1. A coupling structure characterized in that a terminal is provided via a dielectric material having a cylindrical shape and having protrusions or protrusions on an outer circumferential surface, and the terminal and the conductive film are electrostatically coupled. (2) The dielectric material in which the hole is formed is a dielectric material of a dielectric coaxial resonator, and the conductive film formed on the inner surface of the hole is an inner conductor of the dielectric coaxial resonator. Scope of claim for utility model registration
Bonded structure described in (1).