JPH0534097Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Purpose of the invention] (Field of industrial application) This invention is an SH (self-healing type) consisting of a capacitor element embedded in a resin such as epoxy.
It relates to capacitors, and in particular to SH capacitors with improved structure of the resin case part. (Conventional technology) Conventionally, capacitor elements are embedded in resin.
As SH capacitors, those shown in FIGS. 3A and 3B are known. In the SH capacitors shown in FIGS. 3A and 3B, an electrode lead-out part 2 made of metallicon is formed on the end face of a capacitor element 1, a lead wire 3 is connected to this electrode lead-out part 2 by welding or soldering, and in this state a resin case is 4, filled with resin such as epoxy resin 5, and sealed. However, in the SH capacitor configured as above, the internal pressure is reduced due to heating, shrinkage, and cooling during resin curing, and this reduced pressure tends to cause corona discharge, which causes problems such as capacity reduction and shortened life. It was hot. On the other hand, there is also an SH capacitor in which an elastic material such as urethane or rubber is interposed between the capacitor element 1 and the epoxy resin 5 as a buffer material to alleviate mechanical stress. However, even in this case, it is hardly possible to absorb the decrease in the pressure of the resin 5, and there is a drawback that the pressure decrease is significant especially when used at low temperatures below room temperature, and the capacitor is likely to deteriorate. (Problems to be solved by the invention) The present invention was proposed to solve the above-mentioned drawbacks of the conventional technology, and its purpose is to:
SH that effectively absorbs internal depressurization and maintains sufficient capacitor capacity and has a long life.
is to provide capacitors. [Structure of the invention] (Means for solving the problems) The SH capacitor according to the invention is characterized in that a hollow resin tube is wound multiple times around the outer periphery of the capacitor element. (Function) In the present invention having the above configuration,
The air inside the resin tube acts as an absorber for the internal pressure of the resin. That is, depending on the pressure change around the element,
As the resin tube expands and contracts,
Since changes in the pressure applied to the element are absorbed, there is no longer any reduction in capacitor capacity or shortening of life. (Example) An example of the SH capacitor according to the present invention as described above will be specifically described with reference to the drawings.
Note that the same parts as in the prior art shown in FIGS. 3A and 3B are denoted by the same reference numerals, and the description thereof will be omitted. *Configuration of the embodiment* Figures 1A and 1B show a basic embodiment of the SH capacitor according to the present invention, in which a capacitor element 1 has an elastic hollow vinyl chloride tube 6 wound several times around its outer periphery. It is housed in a resin case 4 in a closed state and is filled with epoxy resin 5. 2A and 2B show a second embodiment of the present invention, in which a capacitor element 1 formed by winding an elastic hollow vinyl chloride tube 6 is once embedded in a soft urethane or wax layer 7. ,
Only the surface thereof, that is, the opening portion of the resin case 4 is filled with the epoxy resin 5. *Effects of Examples* The following tables show the first,
4 is a table comparing the characteristics of the SH capacitor of the second embodiment and the conventional SH capacitor shown in FIG. 3. All samples were made of 5 μm metallized polyethylene terephthalate film.
It consists of 200V-6μF.

【table】

【table】

【table】

[Table] First, as shown in Table 1, in the conventional technology, the occurrence of corona discharge at 20°C is 150 to 180V.
, which is lower than the rated voltage of 200V,
In the first and second embodiments of the present invention, the occurrence of corona discharge at 20° C. is 210 to 240 V and 240 to 280 V, which is the rated voltage of 200 V or more. The voice is
The air inside the PVC tube 6 acts as a pressure absorber, and the tube 6 expands and contracts slightly in response to changes in the pressure around the capacitor element 1, absorbing a considerable amount of pressure changes around the capacitor element 1, and as a result, the pressure decreases. This is thought to be because there are no significant changes. Further, effects such as release of gas generated by healing (pressure absorption) and absorption of swelling of the element are also considered. Further, as shown in Table 2, regarding the capacitance change, in each of the examples of the present invention, a change that is one order of magnitude smaller than the amount of change in the prior art is observed. moreover,
As shown in Table 3, each of the examples of the present invention can be expected to have an estimated lifespan of 10 times or more compared to the conventional technology. Therefore, according to each of the embodiments of the present invention, internal reduced pressure can be effectively absorbed, and as a result, sufficient capacitor capacity can be maintained and the life of the capacitor can be extended. As is clear from each table, in the second embodiment in which the outer peripheral portion of the capacitor element 1 is once embedded in a soft urethane or wax layer 7, the effect of absorbing pressure changes is even higher than in the first embodiment. ing. *Other Examples* It should be noted that the present invention is not limited to the above-mentioned examples, and for example, the number of turns of the resin tube wound around the capacitor element can be selected as appropriate.
The material is not limited to vinyl chloride either. [Effects of the invention] As explained above, in the present invention, internal pressure changes can be effectively absorbed by improving the simple structure of winding a resin tube around the capacitor element. We can provide stable SH capacitors that can maintain sufficient capacitance and have a long life.

[Brief explanation of the drawing]

1A and 1B are an internal side view and an internal front view showing a basic embodiment of the SH capacitor according to the present invention, and FIGS. 2A and 2B are an internal side view and an internal front view showing another embodiment according to the present invention. , Figure 3 A and B are conventional SH
FIG. 3 is an internal side view and an internal front view showing the capacitor. 1... Capacitor element, 2... Electrode lead-out part, 3
... Lead wire, 4 ... Resin case, 5 ... Epoxy resin, 6 ... Vinyl chloride tube, 7 ... Urethane or wax layer.

Claims (1)

[Scope of utility model registration claims] (1) SH consisting of a capacitor element embedded in resin
The capacitor is characterized in that a hollow resin tube is wound multiple times around the outer periphery of the capacitor element.
SH capacitor. (2) Utility model registration claim No. 1 for using epoxy resin as the resin for embedding capacitor elements
SH capacitor described in section. (3) Utility model registration claim described in paragraph 1 that uses a vinyl chloride tube as a resin tube.
SH capacitor. (4) The SH capacitor according to claim 1, wherein the capacitor element is once embedded in a urethane or wax layer, and an epoxy resin layer is formed on the surface of the urethane or wax layer.