JPH036007A - Electric double layer capacitor - Google Patents

Abstract

PURPOSE:To obtain airtightness of an insulating case by a method wherein a volume of a bonding overlap width at a lead terminal extraction sidewall of the insulating case and at a lid sheet is made equal to a volume of a bonding overlap width at a sidewall facing the lead terminal extraction sidewall and at the lid sheet. CONSTITUTION:When a sidewall 12 used to extract terminals 3, 8 is bonded to a lid sheet 6, semicircular ribs 14 are formed around protrusions 10, 11 and a bonding operation is executed by using the ribs. In a bonding structure at an insulating case 1 and at the lid sheet 6, it is set that a volume of a bonding overlap width at a terminal extraction sidewall 12 and at a sidewall 15 in a position facing it is identical. In addition, it is set that also a volume of a bonding overlap width at opposite sidewalls 16, 17 of two remaining sides and at the lid body 6 is identical to that of the terminal extraction sidewall 12. Thereby, it is possible to execute an overall uniform bonding operation and the insulating case 1 can be made completely airtight.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to electric double layer capacitors used in electronic circuits,
In particular, it relates to a fusion structure for sealing an insulating case that houses an electric double layer capacitor element and an electrode plate.

<Prior art> Figures 5 and 6 show a conventional electric double layer capacitor, in which 1 is a bottomed box-shaped insulating case made of an insulating material;
An electrode plate 2 made of a metal plate is placed on the bottom of the electrode plate 2, and its lead terminal 3 is made to protrude outside from a notch 4 in the side wall 12.

Reference numeral 5 denotes an electric double layer capacitor element, and a plurality of electric double layer capacitor elements are housed in a stacked state inside the insulating case 1 so as to overlap with the electrode plate 2.

Reference numeral 6 denotes a lid plate that closes the upper opening of the insulating case 1. The electrode plate 7 stacked on the lower surface of the cover plate is placed on the laminated electric double layer capacitor element S, and the lead terminal 8 of the electrode plate 7 is connected to the cutout of the insulating case l. With the protrusion 10.11 provided on the lower surface of the drawer cover plate 6 fitted into the cutout 4.9, the overlapping portion of the insulating case 1 and the cover plate 60 are fused by ultrasonic welding or the like. The clothes are integrated.

In the above electric double layer capacitor, in order to maintain the characteristics of the electric double layer capacitor element 5 housed inside the insulating case 1, the insulating case 1 and the cover plate 6 are welded together.
The inside of the insulating case 1 must be configured to be airtight.

The insulating case 1 and the cover plate 6 are formed using an insulating synthetic resin such as PBT, and are welded together by a method such as ultrasonic welding to make the inside airtight.

By the way, the shape of the fused portion between the insulating case 1 and the lid plate 6 is not the same on all four sides, as in the examples shown in FIGS. The fused portion with the plate 6 has a shape that is significantly different from the other sides.

<Problems to be Solved by the Invention> By the way, when performing ultrasonic welding of the insulating case 1 and the cover plate 6, if the shapes of each side are different, there will be variations in the way each side melts, and the welded part will be There is a problem that some parts are fused and others are not, making it impossible to make the inside of the insulating case completely airtight.

The purpose of this invention is to solve the above-mentioned problems, and to solve the problem that the ultrasonic welding between the four sides of the insulating case and the cover plate is uneven (
It is an object of the present invention to provide an electric double layer capacitor that can be used in an insulating case to ensure airtightness inside the insulating case.

<Means for Solving the Problems> In order to solve the above-mentioned problems, the present invention solves the following problems:
The volume of the welding margin between the side wall facing the lead terminal drawer side wall and the lid plate is made equal.

Effect> Since the volume of the welding margin between the lead terminal drawer side wall of the insulating case and the cover plate of the side wall opposite to this side wall is equal, when the insulating case and cover plate are ultrasonically fused, both sides The melting process at the fused portion between the wall and the cover plate becomes uniform, ensuring airtightness of the insulating case.

<Embodiments> Hereinafter, embodiments of the present invention will be described based on FIGS. 1 to 4 of the accompanying drawings.

The basic structure of the electric double layer capacitor is the same as that shown in FIGS. 5 and 6, so the same parts will be explained using the same figures.

As shown in FIG. 5, the joint portion between the insulating case l and the cover plate 6 is divided into a terminal drawer portion and three other sides, and the three sides have basically the same shape.

There are several types of joint methods for fusing the insulating case l and the cover plate 6 by ultrasonic welding. For example, as shown in FIGS. 1(A) and 1(B), The protrusion 13 provided on the insulating case 1 and the peripheral wall of the insulating case 1 are fused together using a scarf joint method in which the protrusion 13 is fitted to the peripheral wall of the insulating case 1 using an inclined surface.

On the other hand, as shown in FIGS. 2 and 3, the side wall 12 from which the terminal 3.8 is pulled out and the cover plate 6 are fused together at the protrusion 10111.
A semicircular rib 14 is provided around the periphery of the terminal drawer side wall 12, and the position facing the terminal drawer side wall 12 and the position facing each other are side wall 1 in
The volumes of the fusion allowances of No. 5 are set to be the same.

Incidentally, it is preferable that the volume of the welding margin between the remaining two opposing side walls 16 and 17 and the lid body 6 is set in the same manner as the terminal drawer side wall 12.

Here, the volume of the welding margin differs depending on the joint type, but for example, in the case of the above-mentioned scarf joint, as shown in FIG. is melted, and this part is called fusion allowance 3.

By calculating the area of this hatched portion 19 and integrating it in the length direction, the volume of the fusion margin on the - side is determined.

Next, when the rib joint method is adopted for the terminal drawer side wall 12, the semicircular rib 14 is melted and fused as shown in FIG. 3(B).

This is multiplied by the length of the rib 14 to find the volume of the welding margin.

The radius and height of the rib 14 are set so that this volume is equal to the volume of the welding margin between the side wall 15 and the protrusion 13.

In addition to the above, joint methods include shear joints (Fig. 4 (A)) and bead joints (Fig. 4 (B)).
)) and the Guirectage Indian method (Figure 4 (C)), and these can be considered in the same way.

The electric double layer capacitor of the present invention has the above-mentioned structure, and when the insulating case 1 and the cover plate 6 are fused together by ultrasonic fusion, the drawer side wall 12 of the terminal 3.8 and the side wall opposite to this side wall 12 are Since the volumes of the welding margins 15 are set equal, the overall balance at the joint between the insulating case 1 and the cover plate 6 is maintained, and the ultrasonic welding of the four sides with different shapes becomes uniform over the entire surface, resulting in no fusion bonding. There is no generation of parts, and the insulating case l
Improves airtightness inside.

Effects> As described above, according to the present invention, in an electric double layer capacitor in which a cover plate is fused by ultrasonic welding to an insulating case that houses an electric double layer capacitor element, the terminal drawer side wall of the insulating case and this side wall Since the volume of the welding margin between the cover plate and the opposite side wall is made equal, the overall balance is maintained when welding the cover plate to the insulating case, and uniform welding can be performed on the entire surface. Complete airtightness is possible.

[Brief explanation of drawings]

Each of FIGS. 1 to 4 is an explanatory diagram showing different examples of the joint method of the insulating case and the cover plate, FIG. 5 is an exploded perspective view of an electric double layer capacitor, and FIG. 6 is a longitudinal sectional view of the same. FIG. 7 is an exploded perspective view showing another example of the insulating case and the cover plate. 1... Insulating case 2.7... Electrode plate 3.8... Terminal 4.9... Notch 5... Electric double layer capacitor element

Claims (1)

[Claims] Electrode plates are stacked on both sides of multiple laminated electric double layer capacitor elements, and this is housed in a synthetic resin insulating case. The upper opening of the insulating case was closed with a cover plate, the protrusion provided at the bottom of the cover plate was fitted into the notch, and the overlapping part of the insulating case and cover plate was fused using ultrasonic welding. The electric double layer capacitor is characterized in that the volume of the fusion bond between the lead terminal drawer side wall of the insulating case and the cover plate is equal to the volume of the fusion bond between the side wall facing the lead terminal drawer side wall and the cover plate. electric double layer capacitor.