JPH0411717A - 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 fragile sections are formed to the leading-out terminal at regular intervals, the leading-out terminal is successively bent alternately in the fragile sections, 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. Fragile sections 7 composed of holes formed by a press, etc., are formed to the terminal 3 at regular intervals. The terminal 3 is bent alternately, and stretched. Consequently, the terminal 3 is not returned to an original state completely, and is brought to the state in which sections near 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. Accordingly, the irregular 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.

[Conventional technology]

Tubular electrolytic capacitors are manufactured by connecting the electrode lead terminal led out from one end face of the capacitor element to the inner bottom face of the exterior case, and then connecting the electrode lead terminal led out from the other end face to the external lead wire, and connecting it to the opening. It is configured to be electrically connected to the outside by penetrating the sealing body that seals it.

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.

[Problems 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 process of housing the capacitor element in the exterior case, adjacent weakened parts 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 to solve the problem]

This invention provides a method for manufacturing a tubular electrolytic capacitor, in which weak parts are provided at regular intervals in electrode lead terminals led out from a capacitor element, and after the weak parts are sequentially and alternately bent, the bent electrode lead terminals are It is characterized in that the capacitor element is housed in the outer case by extending it and connecting the tip of the electrode lead terminal to the end face of the outer case.

[Effect]

In the process of housing the capacitor element l in the exterior case 2, by alternately bending the electrode extension terminals 3 at the fragile portions 7 in advance, the electrode extraction terminals 3 housed in the exterior case 2 are folded regularly. .

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

In the process of housing the capacitor element 1 in the exterior case, the force applied to bend the electrode lead terminal 3 is concentrated on the fragile portion 7, which is the location where the electrode lead terminal 3 is bent. Therefore, the electrode lead-out terminal 3 comes to bend again at this weakened portion 7. Then, since the vicinity of the fragile portion 7 remains slightly bent in that direction, it 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.

1(a) to e) are partial sectional views showing the manufacturing process of the tubular electrolytic capacitor of the present invention, FIG. 3 is a perspective view showing the electrode lead-out terminal of the tubular electrolytic capacitor of the present invention, and FIG. 4 FIG. 2 is a perspective view showing an electrode lead-out terminal according to a second embodiment of the present invention.

The exterior case 2 that houses the capacitor element l shown in FIGS. 1(d) and (el) is formed of a metal such as aluminum into a cylindrical shape with a bottom. Also, an external terminal 6 is connected to the outer bottom surface of the case 2. There is.

The capacitor element 1 is formed into a cylindrical shape by winding an anode foil and a cathode foil with a separator in between, and 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. The electrode lead terminal 3 is provided with weakened portions 7 made of holes at regular intervals, which are formed by means such as pressing.

Then, as shown in FIG. 1(b), the electrode lead terminals 3 are alternately bent at the weakened portions 7. After this, Figure 1 (C
), the bent electrode lead terminal 3 is stretched out. When the electrode extension terminal 3 is stretched in this manner, the electrode extension terminal 3 does not completely return to its original state, and the vicinity of the fragile portion 7 remains slightly bent.

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, as shown in FIG. 1(e), when the capacitor element 1 is housed in the outer case 2, the electrode lead terminal 3 is bent at the weakened portion 7. Regarding the bending direction, since the electrode lead terminal 3 remains slightly bent near the fragile portion 7, it is regularly folded into a shape bent by -degree.

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.

Further, as a second embodiment, as shown in FIG. 4, concave fragile portions 27 formed by cutting or pressing are provided on both sides of the electrode terminal 23 at regular intervals. good. This electrode lead terminal 23
In the case of using a sheet, the sheet is bent alternately at the weak part 27, folded regularly, and then stretched, leaving the vicinity of the weak part 27 slightly bent, in exactly the same way as in the first embodiment. state. Therefore, when the electrode lead terminal 23 is bent again, the electrode lead terminal 23 is bent at the weak part 2.
At step 7, it is folded again into a regular shape with multiple bends and is properly stored in an outer case.

Furthermore, in the electrode lead terminal 23 of the second embodiment, it is possible to prevent the electrode lead terminal 23 from twisting when it is bent, so that the electrode lead terminal 23 can be folded more properly and regularly. , it is possible to prevent the welded portion from coming off at the inner bottom surface.

〔Effect of the invention〕

According to this invention, the electrode lead-out terminal led out from the capacitor element and connected to the inner bottom surface of the exterior case is bent once, and then the bent electrode lead-out terminal is stretched.
Since the capacitor element is connected to the inner bottom surface of the outer case and the capacitor element is housed in the outer case, the electrode lead-out terminal is folded into a bent shape at the fragile part, and is properly aligned with the gap between the end surface of the capacitor element and the inner bottom surface of the outer case. It will be stored in.

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 electrode lead-out terminal can be kept to a minimum, allowing the electrolytic capacitor to be made smaller.

Furthermore, since the folded state of the electrode lead terminals of each electrolytic capacitor is uniform, variations in electrical characteristics due to the storage state of the electrode lead terminals are eliminated, and the reliability of the tubular electrolytic capacitor is improved.

[Brief explanation of the drawing]

1(a) to e) are partial cross-sectional views showing the manufacturing process of the tubular electrolytic capacitor of the present invention, FIG. 2 is a partial cross-sectional view showing the conventional tubular electrolytic capacitor, and the third FIG. 4 is a perspective view showing an electrode lead terminal of a tubular electrolytic capacitor according to a second embodiment of the present invention. 11... Capacitor element 12... Exterior case 13.23... Electrode lead terminal 14... Electrode lead terminal 15... External lead wire 16... External terminal 27... Fragile part 18...・Sealing body

Claims (1)

[Claims] (1) In a method for manufacturing a tubular electrolytic capacitor, weak parts are provided at regular intervals on the electrode lead terminals led out from the capacitor element, and after the weak parts are sequentially and alternately bent, the bent electrode lead terminals are stretched and , a method for manufacturing a tubular electrolytic capacitor, characterized in that the tip of the terminal is connected to the inner bottom surface of the outer case, and the capacitor element is housed in the outer case.