JP2016063066A - Electrolytic capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrolytic capacitor that suppresses reduction in voltage resistance while enhancing acoustic properties.SOLUTION: The electrolytic capacitor includes: a capacitor element 7 around which an anode foil 1, on a surface of which an oxide film is formed, and a cathode foil 2 are wounded through a separator 3; a bottomed cylindrical outer case for accommodating the capacitor element; and a sealing body for sealing an opening part of the outer case. For the separator 3, blended paper containing hornet silk made of a cocoon of hornets is used.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an electrolytic capacitor, and more particularly to improvement of a separator.

  Conventionally, an anode foil of a valve metal such as aluminum that has been subjected to an etching treatment and an oxide film formation treatment and a cathode foil of a valve metal such as aluminum that has been subjected to an etching treatment are wound through a separator to form a capacitor element. An electrolytic capacitor is known which is formed and impregnated with a driving electrolyte in this capacitor element and then housed in a case (see, for example, Patent Document 1).

  In the electrolytic capacitor of Patent Document 1, for the purpose of improving sound quality when used in an acoustic device, a mixed paper of rice straw fibers and manila hemp having denseness and uniformity is used as a separator. The electrolytic capacitors disclosed in Examples 1 and 2 of Patent Document 1 both use a separator made of mixed paper of 30% by weight of rice straw fibers and 70% by weight of Manila hemp, and are used in Example 1. The separator used is not embossed, and the separator used in Example 2 is embossed. As a result of using these aluminum electrolytic capacitors as an output coupling capacitor of a CD player and evaluating sound quality, the embossed example 2 is superior to the example 1 in which the separator is not embossed. The acoustic characteristics are obtained. That is, it is known that higher acoustic characteristics can be obtained by embossing the separator.

Japanese Patent No. 2999949

  However, when embossing is applied to a separator made of mixed paper of rice straw fiber and manila hemp to enhance acoustic characteristics, the insulation is lowered due to mechanical stress applied to the separator, and the withstand voltage is lowered. Occurs.

  The present invention solves the above-described problems, and an object of the present invention is to provide an electrolytic capacitor capable of obtaining a sufficient withstand voltage while enhancing acoustic characteristics.

  The electrolytic capacitor of the present invention comprises a capacitor element in which a valve metal anode foil and a cathode foil are wound via a separator, a bottomed cylindrical outer case for housing the capacitor element, and an opening of the outer case. An electrolytic capacitor including a sealing body for sealing, wherein the separator is made of a mixed paper containing hornet silk made of sparrow beak.

  According to this configuration, as the separator, a mixed paper containing hornet silk made from sparrow bean cocoon having the property of imparting high insulation in addition to denseness and uniformity is used. Therefore, it has high acoustic characteristics due to the denseness and uniformity of the hornet silk, and a high withstand voltage can be obtained due to the high insulation of the hornet silk.

  In the electrolytic capacitor of the present invention, the separator may be a mixed paper subjected to embossing.

  According to this configuration, due to the high insulation of hornet silk, when the acoustic characteristics are further improved by embossing, the insulation is reduced due to the mechanical stress applied during embossing, and thus withstand voltage Even if it falls, sufficient withstand voltage as an electrolytic capacitor can be obtained.

  In the electrolytic capacitor of the present invention, the embossed separator is preferably a mixed paper in which 10 to 50% by weight of hornet silk is blended with Manila hemp.

  According to this configuration, it is possible to reliably improve the acoustic characteristics while reliably obtaining the effect of suppressing the decrease in pressure resistance.

  In the electrolytic capacitor of the present invention, the separator may be a mixed paper that has not been embossed. In this case, a mixed paper in which 10 to 50% by weight of hornet silk is blended with Manila hemp is preferable.

  According to the present invention, as the separator, a mixed paper containing hornet silk made from sparrow bean cocoon having the property of imparting high insulation in addition to denseness and uniformity is used. Therefore, it has high acoustic characteristics due to the denseness and uniformity of hornet silk. Furthermore, the high insulation property of hornet silk can be embossed to further enhance the acoustic characteristics, so that a sufficient withstand voltage can be achieved even if the insulation is reduced due to mechanical stress applied during embossing.

It is a principal part cutting front view of the electrolytic capacitor concerning one embodiment of the present invention. FIG. 2 is an exploded perspective view of the capacitor element shown in FIG. 1.

  A preferred embodiment of the present invention will be described below with reference to the drawings.

(Configuration of aluminum electrolytic capacitor)
As shown in FIG. 1, the aluminum electrolytic capacitor 10 of this embodiment mainly includes a capacitor element 7, an outer case 9, and a sealing body 8.

  As shown in FIG. 2, the capacitor element 7 is formed by connecting an aluminum anode foil 1 that has been subjected to an etching process and an oxide film forming process and an aluminum cathode foil 2 that has been subjected to an etching process through a separator 3. It is formed by being wound into a shape and fixed with an element stop tape 6. A lead tab (not shown) is connected to the anode foil 1 and the cathode foil 2, and lead portions 4 and 5 are drawn from the anode foil 1 and the cathode foil 2 through the lead tab, respectively. The capacitor element 7 is impregnated with a driving electrolyte.

  The outer case 9 is made of a light metal such as aluminum, and is formed in a bottomed cylindrical shape so that the capacitor element 7 can be accommodated therein. The sealing body 8 is a member for sealing the opening of the outer case 9 and is made of elastic rubber. Insertion holes 8 a and 8 b for inserting the lead portions 4 and 5 of the capacitor element 7 are formed in the sealing body 8. After the sealing body 8 is attached to the opening of the outer case 9, the outer case 9 is sealed by drawing.

(Example)
The separator is composed of a mixed paper of two kinds of fibers, fiber 1 and fiber 2, and 14 kinds of samples having various properties shown in Table 1 are used. Rating 63V, 100 μF, outer diameter diameter 18 mm, length 35. A 5 mm aluminum electrolytic capacitor was produced, and designated as Examples 1 to 9 and Comparative Examples 1 and 2. Examples 1 to 9 employ Manila hemp as fiber 1 and hornet silk made from sparrow beak as fiber 2; Comparative Examples 1 and 2 employ manila hemp as fiber 1 and rice straw as fiber 2 Yes.

<Comparison test 1>
For the aluminum electrolytic capacitors of Examples 1 to 9 and Comparative Examples 1 and 2 described above, an overvoltage of 63.1 V or more exceeding the rated voltage is increased at a rate of 0.1 V / second at a constant current of 1 mA when connected to a DC power source The dielectric breakdown voltage when the product failed was examined. The results are shown in Table 2.

  As shown in Table 2, the aluminum electrolytic capacitors of Examples 1 to 4 without embossing have a higher breakdown voltage than the aluminum electrolytic capacitor of Comparative Example 1 without embossing. Moreover, the aluminum electrolytic capacitors of Examples 5 to 9 with embossing also have a higher breakdown voltage than the aluminum electrolytic capacitor of Comparative Example 2 with embossing.

  According to the properties of each separator used in Examples 1 to 9 and Comparative Examples 1 and 2 shown in Table 1, the separators of Examples 1 to 9 containing hornet silk and a comparison not containing hornet silk The separators of Examples 1 and 2 have the same density, but the air permeability (air density), which is the time required for air to permeate within a certain period of time, is greater for the separators of Examples 1 to 9. It shows the characteristics that increase in general. Such a characteristic of the separator contributes to a high insulation property in which a short-circuit current between the electrodes hardly flows.

<Comparison test 2>
The aluminum electrolytic capacitors of Examples 1 to 9 and Comparative Examples 1 and 2 described above were used as output coupling capacitors for a CD player, and the sound quality was evaluated by a 10-point system. The results are shown in Table 3. Each numerical value shown in Table 3 means that the larger the value, the better the sound quality.

As shown in Table 3, the aluminum electrolytic capacitors of Examples 1 to 4 without embossing have higher sound quality (average) than the aluminum electrolytic capacitor of Comparative Example 1 without embossing.
In addition, the aluminum electrolytic capacitors of Examples 5 to 9 with embossing also have the same or higher sound quality (average) than the aluminum electrolytic capacitor of Comparative Example 2 with embossing. In particular, the dielectric breakdown voltage of the separator is high because the blending amount of hornet silk is 10% by weight or more and 50% by weight or less without embossing, and 10% by weight or more and 50% by weight or less even with embossing. A sound quality aluminum electrolytic capacitor can be obtained.

  As described above, in the aluminum electrolytic capacitor 10 according to the present embodiment, the separator 3 interposed between the anode foil 1 and the cathode foil 2 has a property of imparting high insulation in addition to denseness and uniformity. A mixed paper containing hornet silk made from sparrow bean cocoon is used. Therefore, it has high acoustic characteristics due to the denseness and uniformity of hornet silk. Furthermore, the high insulation properties of hornet silk enhance the acoustic characteristics by embossing, so that a high withstand voltage can be realized even if the insulation becomes low due to mechanical stress applied during embossing.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various design changes can be made as long as they are described in the claims. Is.

  In the above-described embodiment, the case where the separator is a mixed paper of manila hemp and hornet silk has been described. However, the present invention is not limited to this. That is, the separator may be a mixed paper containing at least hornet silk, and may be, for example, a mixed paper of esparto or kraft pulp and hornet silk.

1 Anode foil 2 Cathode foil 3 Separator 6 Element stopper tape 7 Capacitor element 10 Electrolytic capacitor

Claims (4)

A capacitor element in which a valve metal anode foil and a cathode foil are wound through a separator;
A bottomed cylindrical outer case for storing the capacitor element;
An electrolytic capacitor comprising a sealing body that seals the opening of the outer case,
The separator is made of a mixed paper containing hornet silk made from sparrow beak.   The electrolytic capacitor according to claim 1, wherein the separator is a mixed paper subjected to embossing.   3. The electrolytic capacitor according to claim 1, wherein the separator is a mixed paper in which 10 to 50 wt% hornet silk is blended with Manila hemp.   2. The electrolytic capacitor according to claim 1, wherein the separator is a mixed paper that has not been embossed and is a mixed paper in which 10 to 50 wt% hornet silk is blended with Manila hemp.