JPS6112667Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flat electrolytic capacitor in which a capacitor element and an electrolyte are completely sealed to prevent leakage of the electrolyte, particularly at the electrode lead-out portion.

A general electrolytic capacitor has an electrolytic solution and a capacitor element built into a metal case, and an elastic sealing material such as rubber is inserted into the opening of the case.
The structure is sealed by drawing the case.

However, this structure has shape restrictions and is unsuitable for electrolytic capacitors with special shapes such as thin or flat shapes, and in the case of electrolytic capacitors with such shapes, other structures must necessarily be used. .

That is, the material is formed into a bag shape by laminating and pasting an insulating synthetic resin film on the outer surface of a metal film.
Then, the peripheral edge is heat-pressed to form a bag-like case with one end open.

Next, the capacitor element and the electrolyte are sealed in this bag-like case, and the lead wire connected to the capacitor element is brought out through the opening, and under this condition, the opening is heat-pressed and sealed.

However, in the flat electrolytic capacitor of the conventional structure described above, a gap easily forms between the synthetic resin part of the bag-shaped case and the lead wire, and the adhesion here is not completed completely, causing the sealed electrolyte to leak from there. I was afraid.

This invention was created in view of the above problems.
The electrolytic tabs connected to the capacitor element are each welded to separate metal films, and the periphery of the other metal film is crimped with an insulating synthetic resin film interposed, and the capacitor element and electrolyte are sealed inside. The object of the present invention is to provide a flat electrolytic capacitor that has no gaps and eliminates the risk of electrolyte leakage.

Embodiments of the present invention will be described below with reference to the drawings.

First, a plurality of electrode tabs 2a and 2b formed into arbitrary shapes are welded to both electrode terminal portions of the capacitor element 1, respectively.

The other ends of the electrode tabs 2a, 2b are welded to the inner surfaces of a pair of thin metal plates, for example, metal films 3a, 3b, cut into a predetermined shape, and the peripheral edges of both metal films 3a, 3b are insulated. After overlapping them with a thin film body such as a synthetic resin film 4 interposed therebetween, they are tightly bonded by heat and pressure bonding. Close the opening in the above state. Next, arbitrary external electrodes 7a and 7b are welded to the outer surfaces of both metal films 3a and 3b, respectively.

With this configuration, the circuit configuration of one external electrode 7a - metal film 3a - electrode tab 2a - capacitor element 1 and the other external electrode 7b
The circuit configuration of ~metal film 3b~electrode tab 2b~capacitor element 1 is formed.

Further, the case bag 5 encloses only the capacitor element 1 and the electrolyte 6, and its entire outer periphery is tightly sealed with the synthetic resin film 4 interposed therebetween, resulting in a completely sealed state. Therefore, it is possible to completely prevent an accident in which a gap is formed at the lead wire drawn out from the inside to the outside, as in a conventional flat capacitor, and the electrolyte leaks out from the gap.

In addition, the shapes of the metal films 3a, 3b and the synthetic resin film 4 can be freely set, and the electrode tabs 2
Of course, the shapes of the external electrodes 7a and 7b of a and 2b are free, and the welding locations with the metal films 3a and 3b are also arbitrary, so the shape of the flat capacitor as well as the electrode position, direction, and size can be freely determined. It is free. Of course, the synthetic resin film 4 is not necessary if a metal plate or metal film on which an insulating film is laminated and pasted in advance is used.

As explained above, according to the present invention, both electrodes of a capacitor element are connected to the inner surfaces of separate metal films, and the peripheral edges of both metal films are welded together via an insulator to form a bag-like case. Since the external electrodes are welded to the outer surfaces of both metal films after the electrolyte is sealed, there is no leakage of the electrolyte, and the position, direction, and overall shape of the external electrodes can be freely adjusted. It is possible to achieve remarkable effects in that it can be formed to

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the outer shape of a flat capacitor according to an embodiment of the present invention, and Fig. 2 is a -
FIG. 1... Capacitor element, 2a, 2b... Electrode tab, 3a, 3b... Metal film, 4... Synthetic resin film, 5... Case bag, 6... Electrolyte, 7
a, 7b...external electrodes.

Claims (1)

[Scope of utility model registration request] Each electrode of the capacitor element is connected to the inner surface of a pair of thin metal plates, and the two metal plates are brought together and an insulating thin film is interposed and welded to the periphery of the thin metal plates to enclose the capacitor element. A flat electrolytic capacitor is formed by forming a bag-like case, filling and sealing an electrolyte in the bag-like case, and further welding external electrodes to the outer surfaces of both of the metal thin plates.