JPS63250810A - Through type capacitor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is applicable to a filter case for preventing microwave leakage from the cathode side lead wire of a magnetron, for example.
The present invention relates to a feedthrough capacitor suitable for use as a filter at a point where a lead wire is drawn out.

[Conventional technology]

Conventional feed-through capacitors, for example, filter feed-through capacitors installed at the point where the lead wire is pulled out from the filter case to prevent leakage of microwaves from the cathode side lead wire of a magnetron, are used in the Utility Model Application Publication No. 57-10, for example.
As disclosed in Japanese Patent No. 4446, the center conductor, that is, the lead wire is perpendicular to the filter case wall, but inside the center conductor, the cylindrical dielectric surrounding the center conductor does not come into direct contact with the center conductor. It was widely used to have an electrode connected to the center conductor on one end surface and an electrode connected to the case on the other end surface. However, in such a structure, the dimensions of the electrode are relatively small, making it difficult to increase the capacitance.

On the other hand, it is easy to construct a structure in which a linear conductor penetrating the inside of a cylindrical dielectric is used as one electrode, and the outer circumferential surface of the dielectric surrounding the outside of the dielectric substantially parallel to the linear conductor is used as the other electrode. A large capacitance can be obtained by making a hole into which the cylindrical dielectric is inserted in a metal plane (for example, a filter case wall) extending at right angles to the central linear conductor (for example, a cathode lead wire). When used with the dielectric outer circumferential electrode in direct contact with the metal plane, the dielectric (usually some type of ceramic) that forms the capacitance and the money luck are generally removed.
However, since metal has a much larger coefficient of thermal expansion than dielectric, when a thermal shock test is performed in which high and low temperatures are periodically repeated, the outer circumferential surface of the dielectric will be affected by temperature changes from the flat metal plate perpendicular to it. As a result, the dielectric material is subjected to intense thermal stress, and repeated stress causes cracks to form in the dielectric material. If a crack occurs, applying high voltage between the central conductor and the metal plane will easily destroy the insulation between the two, making it impossible to function as a capacitor.

[Problems to be Solved by the Invention] The present invention solves the problems of the conventional feedthrough capacitors, and uses a linear conductor that directly penetrates the dielectric as one electrode.
It is an object of the present invention to provide a feedthrough capacitor which has a structure in which the outer peripheral surface of the dielectric material is used as the other electrode, but which does not cause cracks in the dielectric material even when subjected to a thermal shock test in which high and low temperatures are periodically repeated. purpose.

[Means for solving problems]

In order to solve the above problems, in the present invention, the dielectric outer peripheral surface electrode of the feedthrough capacitor is connected to the
The connecting member was connected to a metal plate extending approximately perpendicularly to the linear central conductor, and this connecting member was provided with a stepped portion that was substantially parallel to or nearly parallel to the linear conductor. Furthermore, a plurality of notches are provided at the end of the stepped portion of the connecting member on the side to be connected to the dielectric outer circumferential surface electrode, and the end of the resulting plurality of claw-like portions is
If the non-notched side of the connecting member is connected to the metal plate at the dielectric outer peripheral surface electrode, the thermal shock mitigation effect of the stepped portion becomes even more remarkable.

[Effect]

With the above structure, the strong force that causes the area around the hole drilled in the metal plate to move in the radial direction due to temperature changes will no longer act directly on the dielectric outer circumferential surface of the capacitor. Only the force that expands and contracts the ends of the section will act. In particular, if a notch is provided, the force acting on the outer circumferential surface of the dielectric will be only the force that bends the plate of the claw-shaped part created by providing the notch. The wall thickness of the end portion of the stepped portion in contact with the surface may be made thinner.

〔Example〕

FIG. 1 is a longitudinal sectional view of a first embodiment of the present invention.

1 is a dielectric material made of ceramics, etc. For example, the entire outer surface is first plated with nickel, and then the upper and lower end surfaces are ground to peel off the nickel plating layer, and the nickel plating layer that will serve as the electrode is applied only to the inner and outer cylindrical surfaces. 2 is a center conductor which is inserted into the dielectric 1 and fixedly connected by soldering or the like. Reference numeral 3 denotes a connecting member having a stepped portion 3a formed therein. The other stepped portion 3b shown is a portion into which a plastic case 5.6 is fitted, which accommodates the filling resin 4 to be injected later and improves the creeping withstand voltage of the capacitor.

Note that a good effect can be obtained by press-molding the step portion 3a and its end portions to be relatively thin.

FIG. 2 is a longitudinal sectional view of a second embodiment of the present invention.

In this embodiment, a notch is made at the end of the connecting member 3 on the side that connects to the electrode on the outer peripheral surface of the dielectric 1, and the connecting member 3 is divided as shown in a perspective view in FIG. 3 to form a claw-like portion 3c. be. The ends of the claw-like portions 3c are soldered to the electrodes on the outer peripheral surface of the dielectric 1. In this embodiment, the hoop stress on the dielectric 1 is reduced, and the claws themselves can also absorb the stress.

Note that in the first embodiment, the step portion 3a of the connecting member 3 is parallel to the center conductor, but it may be close to parallel and diagonal as in the second embodiment.

In addition, in the above embodiment, there is one center conductor, but there are two reciprocating conductors.
It goes without saying that exactly the same effect can be obtained even if one or more conducting wires are arranged centrally.

〔Effect of the invention〕

As explained above, according to the present invention, a highly reliable and inexpensive feedthrough capacitor can be obtained.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a first embodiment of the invention, FIG. 2 is a longitudinal sectional view of a second embodiment of the invention, and FIG. 3 is a perspective view of a connecting member of the second embodiment. 1-dielectric, 2-center electrode, 3-connection member 3a
-・One step part, 4- Filled resin. "t!A 11""゛>I+ 95(-,". \, -2- 3rd Figure 4 - Large tool sharpening

Claims (1)

[Claims] 1. A linear conductor penetrating a substantially cylindrical dielectric is used as one electrode, and an outer circumferential surface of the dielectric surrounding the conductor substantially parallel to the linear conductor is used as the other electrode. , the dielectric outer peripheral surface electrode is
In a feed-through capacitor connected to a metal plate extending approximately perpendicularly to a linear conductor via a connecting member, the connecting member has a stepped portion that is substantially parallel to or nearly parallel to the linear conductor. A feed-through capacitor featuring: 2. A plurality of notches are provided at the end of the stepped portion of the connecting member on the side to be connected to the dielectric outer circumferential surface electrode, and the ends of the resulting plural claw-like portions are connected to the dielectric outer circumferential surface electrode, 2. A feedthrough capacitor according to claim 1, wherein a side of the connecting member without a notch is connected to the metal plate.