JPH0411718A - Manufacture of tubular type electrolytic capacitor - Google Patents

Abstract

PURPOSE:To fold an electrode leading-out terminal properly, and to prevent the damage of a capacitor element by a method wherein the leading-out terminal is successively bent alternately and stretched, the front end of the leading-out terminal is connected to the end face of a sheathing case and the leading-out terminal is housed. CONSTITUTION:A beltlike electrode leading-out terminal 3 is connected to a cathode foil, and led out of an end face reverse to the electrode leading-out terminal 4 of an anode. The terminal 3 is bent alternately, and the terminal 3 is stretched. Consequently, the terminal 3 is not returned to an original state completely, and sections in the vicinity of bent sections are brought to the state in which the sections in the vicinity of the bent sections are left as they are bent slightly. When the front end of the terminal 3 is connected to the inner base of a sheathing case 2 and a capacitor element 1 is housed in the case 2, the terminal 3 is folded regularly in a once bent shape. Accordingly, the irregulr bending of the terminal 3 is removed, thus preventing the damage of the element 1.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing a so-called tubular electrolytic capacitor in which external lead wires are led out in opposite directions.

[Prior Art] In a tubular electrolytic capacitor, an electrode lead terminal led out from one end face of a capacitor element is connected to the inner bottom face of an exterior case, and an electrode lead terminal led out from the other end face is connected to an external lead wire. The opening is electrically connected to the outside by passing through a sealing body that seals the opening.

As shown in FIG. 2(a), in the electrolytic capacitor having such a configuration, the electrode lead terminal 13 connected to the inner bottom surface of the outer case 12 is formed into a flat strip shape with a conductor made of aluminum or the like. ing. Further, this electrode lead terminal 13 is connected to the inner bottom surface of the outer case 12, but when connecting, the capacitor element 11 is connected to the outer case 12.
Since it is necessary to take it outside, the outer case 1
It is formed longer than the vertical dimension of 2.

Then, the electrode lead terminal 13 is connected to the inner bottom surface of the outer case 12 by means such as ultrasonic welding, and then the capacitor element 11 is housed in the outer case 12.

[Problem to be solved by the invention]

However, as shown in FIG. 2(b), the outer case 12
The cathode-side electrode extension terminal 13 housed in the capacitor element 11 may be irregularly bent in the gap between the end surface of the capacitor element 11 and the inner bottom surface of the outer case 12. In such a case, an irregular bending angle is formed in the electrode lead terminal 13, and this bending angle digs into the inside of the capacitor element 11, sometimes even destroying the electrolytic paper insulating the anode foil and the cathode foil. There is a risk that the electrical characteristics of the electrolytic capacitor may be significantly deteriorated, such as short-circuiting or an increase in loss angle.

In order to prevent such inconvenience, the outer case 12
Although it would be possible to obtain a sufficient storage space for the electrode lead terminal 13 by increasing the vertical dimension of the capacitor element 11 or by shortening the dimension of the capacitor element 11, this becomes one of the factors that impede miniaturization of the electrolytic capacitor.

In order to solve the above problems, for example,
It is conceivable to bend the drawer terminal at the unprocessed portion by providing one or more reinforcing portions in the longitudinal direction of the drawer terminal connected to the exterior case, as in the idea disclosed in Japanese Patent No. 8-31400.

However, when the reinforcing portion is provided on the pull-out terminal in this way, although the bending position can be specified, the direction in which the pull-out terminal is bent cannot be specified.

Therefore, in the step of housing a capacitor element in an exterior case, adjacent weakened portions may be bent in the same direction in the unprocessed portion of the lead terminal, in other words, in the weakened portion.

This invention has been made to solve the above-mentioned problems, and an object of the present invention is to properly fold the lead terminals and prevent damage to the capacitor element in the process of housing the capacitor element in an exterior case.

[Means for Solving the Problems] The present invention provides a method for manufacturing a tubular electrolytic capacitor, in which electrode lead terminals led out from a capacitor element are sequentially and alternately bent, and then the bent electrode lead terminals are stretched and the electrodes are This method is characterized in that a tubular electrolytic capacitor is manufactured by connecting the tip of the lead-out terminal to the end face of the outer case and housing the capacitor element in the outer case.

[Effect]

In the step of storing the capacitor element 1 in the outer case 2, by alternately bending the electrode lead terminals 3 in advance, the electrode lead terminals 3 housed in the outer case 2 are folded regularly.

That is, when the alternately bent electrode lead terminals 3 are stretched, the bent portions remain slightly bent.

Then, in the process of housing the capacitor element 1 in the exterior case 2, the force applied to bend the electrode lead terminal 3 is concentrated at the point where the electrode lead terminal 3 is bent once. Therefore, the electrode lead terminal 3 is bent again at this bending portion. Moreover, the direction follows the direction of the bent state, and is again bent in the direction in which it was bent - degree.

[Example] Examples of the present invention will be shown below and explained in more detail.

FIGS. 1(a) to 1(e) are partial cross-sectional views showing the manufacturing process of the tubular electrolytic capacitor of the present invention.

An exterior case 2 housing the capacitor element 1 shown in FIGS. 1(d) and 1(e) is made of metal such as aluminum and has a cylindrical shape with a bottom. An external terminal 6 is connected to its outer bottom surface.

The capacitor element 1 is made by winding an anode foil and a cathode foil with a separator in between to form a cylindrical bulge, which is impregnated with an electrolyte.

Further, an electrode lead terminal 4 is connected to the anode foil, and a round bar-shaped tip portion protrudes from one winding end surface of the capacitor element 1. An external lead wire 5 for electrical communication with the outside is connected to its tip.

On the other hand, a strip-shaped electrode lead terminal 3 is connected to the cathode foil,
The anode is led out from the end face opposite to the end face from which the electrode lead terminal 4 is led out.

Then, as shown in FIG. 1(b), the electrode lead terminals 3 are bent alternately. After this, as shown in FIG. 1(C), the bent electrode lead terminal 3 is stretched. When the electrode lead terminal 3 is stretched in this way,
The electrode lead terminal 3 does not completely return to its original state, but remains slightly bent near the bent portion 11.

Next, as shown in FIG. 1(d), the tip of the electrode lead-out terminal 3 is connected to the inner bottom surface of the outer case 2 by means such as ultrasonic welding.

Therefore, when the capacitor element 1 is housed in the outer case 2, as shown in FIG. When the electrode lead terminal 3 is bent again, the deforming force for bending the electrode lead terminal 3 is concentrated at the bending part, and the electrode lead terminal 3 is deformed at the bend part and is regularly folded into a -degree bent shape. become.

Then, a sealing body 8 made of an elastic member such as rubber and having a through hole is inserted into the open end, and the open end of the outer case 2 is tightened to perform electrolysis as shown in FIG. 1(e). form a capacitor.

In the tubular electrolytic capacitor formed in this manner, the electrode lead terminal 3 led out from the capacitor element 1 and connected to the outer case 2 is properly positioned in the gap between the inner bottom surface of the outer case 2 and the end surface of the capacitor element 1. It will be stored.

Therefore, irregular bending angles of the electrode lead terminals 3 are not formed, and damage to the capacitor element 1 can be prevented.

[Effects of the Invention] According to the present invention, the electrode lead terminal led out from the capacitor element and connected to the inner bottom surface of the exterior case is bent once, and the bent electrode lead terminal is stretched.
After connecting the capacitor element to the inner bottom surface of the outer case, the capacitor element is stored in the outer case, so the electrode lead terminal is folded into a bent shape and is properly stored in the gap between the end surface of the capacitor element and the inner bottom surface of the outer case. will be done.

In this way, by regularly folding the electrode lead-out terminals, bending angles are not formed, and the capacitor element is not damaged by the bending angle, and the end face of the capacitor element and the inner bottom surface of the outer case are prevented from being damaged. The gap between the capacitor and the capacitor can be kept to a minimum for accommodating the electrode lead-out terminal, making it possible to downsize the electrolytic capacitor.

Further, since the folded state of the electrode lead-out terminals of each electrolytic capacitor becomes uniform, variations in electrical characteristics depending on the state of the electrode lead-out terminals are eliminated, and the reliability of the tubular electrolytic capacitor is improved.

[Brief explanation of the drawing]

FIGS. 1A to 1E are partial cross-sectional views showing the manufacturing process of the tubular electrolytic capacitor of the present invention, and FIG. 2 is a partial cross-sectional view showing a conventional tubular electrolytic capacitor. 11... Capacitor element 12... Exterior case 13... Electrode lead terminal 14... Electrode lead terminal 15... External lead wire 16... External terminal 18... Sealing body m1 tb+ Fig. 2 (al (bl (CI Figure 1 dl (sr

Claims (1)

[Claims] (1) In the manufacturing method of a tubular electrolytic capacitor, after the electrode lead terminals led out from the capacitor element are bent in turn and alternately, the bent electrode lead terminals are stretched and the tips of the electrode lead terminals are connected to the inner bottom surface of the exterior case. A method for manufacturing a tubular electrolytic capacitor, which comprises connecting the capacitor element to an external case and housing the capacitor element in an external case.