JPH0614460Y2 - High voltage penetration type porcelain capacitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a high-voltage through-type porcelain capacitor having excellent heat cycle resistance.

[Prior art]

High-voltage feedthrough porcelain capacitors are used as filter capacitors for magnetron tubes in microwave ovens,
Since the microwave oven is originally for heating food rapidly, the condenser provided therein is repeatedly heated and cooled rapidly. Therefore, it is important for this type of capacitor to have excellent heat cycle resistance.

By the way, conventionally, in this type of through-type porcelain capacitor, as shown in FIG. 4, one example is shown in FIG. Capacitor electrodes 16 are also provided on the opposing surfaces, and holes corresponding to the through holes 12 and 13 of the porcelain dielectric 11 are provided in these capacitor electrodes 14, 15 and 16, respectively. Then, the capacitor electrode 16 is connected to a ground plate 17 having a window 18 opened in the center thereof, and the center conductors 19 and 1
9a of the conductor portions 19-1 and 19a-1 to the capacitor electrode 1
Via the metal fittings 20 and 20a connected to the electrodes 4 and 15, the capacitor electrodes 14 and 15, the porcelain dielectric 11, the capacitor electrode 16, and the window 18 of the ground plate 17 are sequentially penetrated, and
-1, 19a-1 are protected by silicon tubes 21, 21a, and further, an insulating case 22 and an insulating cover 23 are fitted on both sides of the ground plate 17 to cover them, and an insulating resin mold such as an epoxy resin is provided inside thereof. It is fixed by (not shown). In addition, 19-2 and 19a-2 in the said drawing have shown the faston tab part.

[Problems to be solved by the invention]

Since the capacitor is installed in the microwave oven by fixing the ground plate 17 to a filter box (not shown), the heat of the microwave is transferred to the porcelain dielectric 11 through the ground plate 17 when the microwave oven is used. Although it is transmitted, since the ceramic dielectric 11 and the ground plate 17 have different heat capacities and coefficients of thermal expansion, peeling occurs at the boundary surface between the insulating resin mold and the ceramic dielectric 11 and the capacitor withstand voltage characteristic deteriorates. There was a problem that it was easy to become

The present invention has been made by paying attention to the above problems of the conventional capacitor, and by improving the heat cycle resistance by reducing the heat transfer amount from the ground plate to the porcelain dielectric, the high voltage having excellent withstand voltage characteristics is obtained. An object is to provide a feedthrough porcelain capacitor.

[Means for solving problems]

According to the present invention, a joint fitting wall portion of a ground plate is joined and fitted between an insulating case and an overlapping portion of an insulating cover, a porcelain dielectric is provided in the insulating case, and a ground electrode of the porcelain dielectric is connected to the ground plate. In a through-type porcelain capacitor in which an insulating resin is injected around the porcelain dielectric inside the insulating case and the insulating cover as well as conducting the connection, a joint fitting wall portion between the insulating case of the ground plate and the overlapping portion of the insulating cover. A high-voltage through-type porcelain capacitor, characterized in that a large number of through-holes are formed in it.

[Action]

Since a large number of through holes are formed in the joint fitting wall portion of the ground plate as described above, the conductive heat transfer area from the ground plate to the porcelain dielectric is reduced, so that the ground plate is used when the microwave oven is used. The amount of heat transferred from the filter box to the porcelain dielectric is reduced via, and peeling at the boundary surface between the porcelain dielectric and the insulating resin mold can be prevented.

〔Example〕

An embodiment of the present invention will be described with reference to the drawings. Although the overall structure of this capacitor is almost the same as that of the conventional example, it is characterized by the structure of the ground plate.

That is, FIG. 1 is a perspective view of the ground plate 1 as viewed from the upper side thereof, and the ground plate 1 has a large number of penetrations in the joint fitting wall portion 2 between the overlapping portions of the insulating case 22 and the insulating cover 23. A hole 3 is formed. In the figure, reference numeral 4 denotes a conducting surface that abuts the capacitor electrode of the porcelain dielectric in the porcelain capacitor (see FIGS. 2 and 3).

2 and 3 show sectional structures of through-type porcelain capacitors constructed by incorporating the above-mentioned ground plate 1, respectively. The ground plate 1 is joined and fitted between the overlapping portions of the insulating case 22 and the insulating cover 23. Insulating resin mold 24 provided together
Is injected into the cylindrical body formed by the insulating case 22 and the insulating cover 23 so as to cover the outer peripheral surface and the inner peripheral surface of the porcelain dielectric 11.

In such a ground plate 1, as a result of forming a large number of through holes 3 in the joint fitting wall portion 2, the heat transfer amount of heat of the filter box transmitted from the electrode 16 to the porcelain dielectric 11 through the ground plate 1 is the first. It is significantly reduced compared to the conventional example of FIG. In FIGS. 2 and 3, the same reference numerals as those shown in FIG. 4 indicate that the members have the same functions as those shown in FIG.

[Effect of device]

As described above, the capacitor of the present invention has a large number of through holes formed in the joint fitting wall of the grounding plate with the insulating case and the insulating cover. Since it is difficult to transfer heat to, the peeling at the interface between the insulating resin mold and the porcelain dielectric is reduced,
This has the effect of improving the heat cycle resistance of the capacitor and therefore reducing the deterioration of the withstand voltage characteristics.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention.
FIG. 1 is a perspective view of the ground plate seen from the upper surface side, FIG. 2 is a front sectional view of a high voltage through type ceramic capacitor, FIG. 3 is a side sectional view thereof, and FIG. 4 is a conventional high voltage through type ceramic capacitor. FIG. 1 ... Grounding plate, 2 ... Joining wall part, 3 ... Through hole, 1
1 ... Porcelain dielectric, 12, 13 ... Through hole, 14, 1
5, 16 ... Capacitor electrode, 17 ... Ground plate, 18 ...
... Window, 19, 19a ... Center conductor, 19-1, 19a-
1 ... Conductor part, 19-2, 19a-2 ... Faston tab part, 20, 20a ... Metal fittings 21,21a ... Silicon tube, 22 ... Insulation case, 23 ... Insulation cover, 24 ... Insulation Resin mold.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References: Showa Sho 52-95039 (JP, U) Showa 54-150868 (JP, U) Japanese Patent Sho 60-28117 (JP, B2)

Claims (1)

[Scope of utility model registration request] 1. A joint fitting wall portion 2 of a grounding plate 1 is joined and fitted between an insulating case 22 and an insulating cover 23, and a porcelain dielectric body 11 is provided in the insulating case 22.
Of the grounding plate 1 in which the ground electrode of the above is electrically connected to the grounding plate 1 and the insulating resin 24 is injected around the porcelain dielectric 11 inside the insulating case 22 and the insulating cover 23. A high-voltage through-type porcelain capacitor, characterized in that a large number of through holes 3 are formed in the joint fitting wall portion 2 between the overlapping portions of the insulating case 22 and the insulating cover 23.