JPS63119513A - 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) This invention relates to capacitors.

(Prior Art) It is already well known that a capacitor is constructed using a film in which electrodes are provided on the surface of a dielectric material. Figure 3 shows a conventional configuration, in which electrode 3 is provided on the surface of a film-like dielectric 2 made of resin such as polypropylene or polyethylene terephthalate by vapor deposition or by overlapping aluminum foil. A capacitor is constructed by winding two films stacked one on top of the other with an offset from each other, applying metallized silicone 4 to both end faces, drawing out electrodes, and molding the entire film with resin.

Alternatively, as shown in FIG. 4, there is also a structure in which a film 1 having electrodes 3 provided in a staggered manner on the front and back surfaces of a dielectric material 2 is wound.

The insulating properties of a capacitor with such a configuration are due to the air space between the film layers5. It also depends on the insulation performance in the gap 6 between the end of the electrode 3 and the metallicon 4 facing it. That is, if the partial discharge inception voltage at this location is low, the insulation properties will deteriorate.

Therefore, conventionally, in order to increase the discharge starting voltage, an insulating material such as paraffin is melted and impregnated. However, such an impregnating agent tends to peel or crack from the film 1 when it is cooled and solidified after impregnation, and therefore, sufficient improvement in dielectric strength may not be expected.

(Problems to be Solved by the Invention) An object of the present invention is to improve insulation performance in an air layer or a gap between films or at the end of an electrode.

(Means for Solving the Problems) This invention comprises a capacitor body by winding a film in which electrodes are stacked on a dielectric material, and impregnating this capacitor body with a liquid impregnating agent for insulation. , the capacitor body is characterized in that, while the impregnating agent is kept in a liquid state inside the capacitor body, only the impregnating agent on the external surface is solidified to form the exterior part.

(Example) An embodiment of the invention will be described with reference to FIG.

Reference numeral 1o denotes a capacitor body formed by winding a film 1, and metallic contacts 4 are provided at both ends of the capacitor body.

FIG. 2 shows a part of it enlarged. In this example, two sheets of the film 1 shown in FIG. 3 are overlapped and wound.

According to this invention, the capacitor body 10 is made of an insulating material.
Vacuum impregnation is performed with a liquid impregnating agent 11 (for example, a resin such as an acid anhydride or an amine curing agent) having excellent dielectric properties.

After sufficiently impregnating the inside of the capacitor body 10 with the impregnating agent 11, it is cured. The impregnating agent 11 that has spread throughout the process up to No. 6 is kept in a liquid state so that only the impregnating agent exposed to the external surface is cured. In the figure, numeral 12 indicates a hardened portion, which is used as it is as an exterior portion.

Various methods can be considered for curing only the portion 12, but in any case, it is necessary to cure the portion 12 within a short period of time. Therefore, specifically, a curing method using, for example, irradiation with ultraviolet rays or electron beams is preferable.

Although the film 1 shown in FIG. 2 is the same as the film 1 shown in FIG. 3, a film 1 as shown in FIG. 4 may be used instead.

In the capacitor constructed as described above, since the impregnating agent 11 inside the capacitor body 10 remains in a liquid state, the insulation performance is maintained sufficiently between the films 1 or the gaps between the electrodes. Become. Furthermore, since it is in a liquid state, even if mechanical stress is applied or expansion or contraction occurs due to heat cycles, it acts to absorb these, so the insulation performance is not impaired.

(Effects of the Invention) As described in detail above, the present invention has the effect that the insulation performance of a capacitor formed by winding a film in which electrodes are provided on a dielectric material can be significantly improved compared to the conventional one. play.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a film showing an embodiment of the present invention;
FIG. 2 is an enlarged sectional view of a part of FIG. 1, and FIGS. 3 and 4 are enlarged sectional views showing a conventional example.

Claims (1)

[Claims] A capacitor body is constructed by winding a film in which electrodes are stacked on a dielectric body, and this capacitor body is impregnated with a liquid impregnating agent for insulation, and the impregnating agent is applied in liquid form inside the capacitor body. The capacitor is formed by solidifying only the impregnating agent on the external surface while maintaining the temperature.