JPS60195920A - Aluminum electrolytic condenser - 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 Field of Industrial Application The present invention relates to an aluminum electrolytic capacitor used in various electronic devices, and more particularly to a separator for an aluminum electrolytic capacitor.

Conventional Structure and Problems A conventional aluminum electrolytic capacitor using this type of aluminum foil is constructed as shown in FIGS. 1 and 2.

That is, the anode internal lead wire 2 is connected to the anode foil 1, which is made by electrochemically roughening a high-purity aluminum foil to expand its surface area, and further forms a dielectric oxide film on this surface by anodizing. , to form an anode body, and a cathode internal lead Ii! 4 are connected to form a cathode body, and the anode body and cathode body are wound together with a separator 5 in between, and impregnated with an electrolytic solution to form a capacitor element 6. The capacitor element 6 constructed in this way was assembled and completed as shown in FIG. That is, the external lead wire 7 is connected to the capacitor element 6, and the bottomed cylindrical metal case 8 is opened.
The elastic sealing body 9 was attached to the open end, and a drawing process was performed to obtain a finished product.

To explain the capacitor element 6 in more detail, generally a wide high-purity aluminum foil is electrochemically roughened, a dielectric oxide film is formed by anodizing, and then cut into desired sizes (width and length). The anode foil 1 and the cathode foil 3 were wound together with a separator 5 interposed therebetween.

When this aluminum foil is cut, a cut burr occurs, and the cut burr breaks through the separator 6, so even if both electrode foils 1 and 3 are wound through the separator 5, both electrode foils 1 and 3 will contact and short-circuit. There were many defects that occurred. Particularly in recent years, with the miniaturization of various electronic devices, there has been a demand for smaller electrolytic capacitors, and the use of thin separators 5 has become common, resulting in an increase in short-circuit failures.

OBJECTS OF THE INVENTION The object of the present invention is to eliminate such conventional drawbacks, and to provide an aluminum electrolytic capacitor that does not cause short-circuit defects even when a thin separator is used.

Structure of the Invention In order to achieve this object, the present invention involves winding an anode foil and a cathode foil together with a separator in which the cut portions of the anode foil and the cathode foil come into contact with each other with a separator that is highly dense or thick, and is impregnated with an electrolyte. The capacitor element is housed in a bottomed cylindrical metal case, and the open end is sealed with an elastic sealant.

This configuration prevents cut edges generated when cutting the anode foil and the cathode foil into desired shapes to penetrate the separator and cause a contact short circuit.

Description of examples An embodiment of the present invention will be described below with reference to the drawings.

The overall structure of the aluminum electrolytic capacitor of the present invention is substantially the same as that shown in the conventional example, and only the features of the present invention will be described here.

In FIG. 3, there are 10 separators, and 1 is an anode foil (the cathode foil is not shown). Of the separators 10, 11 has a normal density or a normal thickness, and 1
2 is a high-density part or a thickened part.

Characteristic comparisons were made between five products of the present invention and conventional products for products with a rated value of 10 V and 4700 μF. Each wound capacitor element, that is, the capacitor element before being impregnated with electrolyte, weighs 5,000
A short circuit test was conducted in which wound capacitor elements with a current of 1 mA or more were judged to be defective, and the results are shown in the table below.

Table: Short-circuit defects Effects of the invention As described above, by using the separator according to the present invention in which the portion where the cut portion of the electrode foil contacts is made highly dense, short-circuit defects are drastically reduced, and its industrial value is great.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a capacitor element, FIG. 2 is a sectional view of an aluminum electrolytic capacitor, and FIG. 3 is a partial perspective view of a separator according to the present invention. 1... Anode foil, 2... Anode internal lead wire, 3... Cathode foil, 4... Cathode internal lead wire, 5...... Separator, 6... Capacitor element, 7... External lead wire, 8...
・Bottomed metal case, 9...Elastic sealing body, 1o・
... Separator, 11 ... Normal density, thick part, 12 ... High density change part. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3

Claims (1)

[Claims] The capacitor element is made by winding the anode foil and cathode foil with a high-density or thick separator around the part where the cut parts of the anode foil and cathode foil come into contact and impregnating it with electrolyte is placed in a bottomed cylindrical metal case. An aluminum electrolytic capacitor whose open end is sealed with an elastic sealant.