JPH0544813B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a leadless aluminum electrolytic capacitor.

Conventional configuration and its problems Conventional chip-type aluminum electrolytic capacitors were constructed as shown in Figures 1a and 1b. That is,
An anode foil, which is made by roughening aluminum foil and forming a dielectric oxide film by anodizing, and a cathode foil, which is made by roughening aluminum foil, are wound through a separator and impregnated with a driving electrolyte to form a capacitor. This capacitor element 1 is housed in a cylindrical metal case 2 with a bottom, and the open end is sealed using an elastic sealing material 3 such as rubber to form an aluminum electrolytic capacitor. The lead wire 4 drawn out from the aluminum electrolytic capacitor is electrically and mechanically connected to the comb-shaped terminal 5 by a method such as welding, and a molded resin sheath 6 is applied to the entire body except for the comb-shaped terminal 5 to create a completed product. It was.

This type of chip-type aluminum electrolytic capacitor is
When mounting on a printed circuit board, a molded resin exterior 6 is applied as described above to provide soldering heat resistance, but generally molded resin exteriors are heated at 10 kg/cm for about 5 minutes at a temperature of 100°C to 150°C. ²
Under such harsh conditions, the driving electrolyte of the electrolytic capacitor evaporates, causing characteristic deterioration such as a decrease in capacitance and an increase in tanδ, and the molded resin exterior 6 However, the problem is that it is extremely expensive. Furthermore, since it is a horizontal type, when it is mounted on a printed circuit board, it occupies a large area of the printed circuit board, which is a factor that hinders miniaturization of various devices.

OBJECTS OF THE INVENTION The present invention eliminates these conventional drawbacks, and aims to provide an inexpensive vertical type leadless aluminum electrolytic capacitor that does not suffer from characteristic deterioration.

Structure of the Invention In order to achieve the above object, the aluminum electrolytic capacitor of the present invention is constructed by housing a capacitor element impregnated with a driving electrolyte in a case and sealing it with an elastic sealing member made of thermoplastic elastomer. , and an electrolytic capacitor body formed by leading out the lead wire connected to the capacitor element from the same end face, and a through hole through which the lead wire passes through and is arranged so as to come into contact with the end face of the electrolytic capacitor body from which the lead wire is drawn out. an insulating plate provided with a hole, a space connected to the through hole is provided on the external surface of the insulating plate, and a lead wire passing through the through hole is folded so that its tip end fits in the space. It is a curved one.

With this configuration, when an aluminum electrolytic capacitor is mounted on a printed circuit board, the tip of the lead wire is housed in the space provided in the insulating plate, so that a convex portion is formed on the surface where the insulating plate contacts the printed circuit board. In other words, the lead wire is flush with the insulating plate, so there is no tilting or wobbling of the aluminum electrolytic capacitor, and it is stable, making it possible to perform the mounting work extremely well and at high speed. It becomes possible.

In addition, since the elastic sealing member that seals the case is made of thermoplastic elastomer, the moldability of the elastic sealing member can be improved compared to conventional rubber-like elastic bodies. Since it is difficult for the drive electrolyte to pass through, the drive electrolyte is less likely to evaporate and the life of the aluminum electrolytic capacitor can be extended.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 2 to 4. In addition, in the figure, the same parts as in FIG. 1 are given the same numbers.

In the figure, 1 is a capacitor element similar to the conventional one, with an anode foil made by electrochemically roughening a high-purity aluminum foil and then anodizing it to form a dielectric oxide film, and a roughened aluminum foil. It is constructed by winding a planarized anode foil with a separator interposed therebetween, and impregnating the wound material with a driving electrolyte. This capacitor element 1 is housed in a cylindrical metal case 2 with a bottom. Further, a lead wire 4 is connected to the anode foil of the capacitor element 1 and the anode foil.

An elastic sealing member 7 made of thermoplastic elastomer is provided at the open end of the metal case 2.
The open end of the metal case 2 is sealed by attaching the metal case 2 and drawing it, thereby forming the electrolytic capacitor body. Further, the lead wire 4 connected to the capacitor element 1 passes through the elastic sealing member 7 and is drawn out from the same end surface.

8 is an insulating plate arranged so as to be in contact with the end surface from which the lead wire 4 of the electrolytic capacitor body is drawn out;
This insulating plate 8 is provided with a through hole 8a through which the lead wire 4 passes. In addition, this insulating plate 8
A recess 8b forming a space connected to the through hole 8a is provided on the outer surface of the recess 8b, and the tip 4a of the lead wire 4 passing through the through hole 8a is bent so as to fit within the recess 8b. ing. In this case, as shown in Fig. 4a and b, the round bar lead wire 4
The leading end portion 4a may be flattened and bent, or may be a round bar lead wire as it is.

With such a configuration, when mounting on a printed circuit board, the leadless aluminum electrolytic capacitor 21 of the present invention is mounted on the printed circuit board 22 with lead wires so that the terminal portion is connected to the conductive pattern, as shown in FIG. 23 and temporarily fixed with an adhesive 24, and then using a soldering method such as reflow, the terminal part of the aluminum electrolytic capacitor 21 is attached to the printed circuit board 22 with solder 25.
What is necessary is to connect and fix it to the conductive pattern 23 of. Also,
If cream solder is used as solder, temporary fixation is possible without using adhesive; in this case,
It is also easy to implement.

Effects of the Invention As described above, according to the aluminum electrolytic capacitor of the present invention, the insulating plate is disposed so as to come into contact with the end surface from which the lead wire is drawn out of the electrolytic capacitor body, and is provided with a through hole through which the lead wire passes. This aluminum electrolytic When mounting a capacitor on a printed circuit board, the aluminum electrolytic capacitor does not tilt or wobble, and as a result, the mounting process can be performed extremely well and at high speed. . Further, since an insulating plate having heat insulating properties is used, a molded resin exterior is not required, and thereby an aluminum electrolytic capacitor without deterioration of characteristics can be manufactured at a low cost.

Furthermore, since the elastic sealing member that seals the case housing the capacitor element impregnated with the driving electrolyte is made of thermoplastic elastomer, the moldability of the elastic sealing member is improved compared to conventional rubber-like elastic materials. This thermoplastic elastomer can improve
Since it is difficult for the driving electrolyte to pass through, the evaporation of the driving electrolyte is reduced, and the life of the aluminum electrolytic capacitor can be extended.

[Brief explanation of the drawing]

1a and 1b are cross-sectional views and side views showing a conventional chip-type aluminum electrolytic capacitor, FIG. 2 is a perspective view showing a leadless aluminum electrolytic capacitor according to an embodiment of the present invention, and FIG. 4A and 4B are perspective views showing a lead shape according to an embodiment of the present invention, and FIG. 5 is a front view showing a state in which the capacitor is mounted on a printed circuit board. . 1...Capacitor element, 2...Metal case, 4
... Lead wire, 7 ... Elastic sealing member, 8 ... Insulating plate, 8a ... Through hole, 8b ... Recess.

Claims (1)

[Claims] 1 A capacitor element impregnated with a driving electrolyte is housed in a case and sealed with an elastic sealing member made of thermoplastic elastomer, and a lead wire connected to the capacitor element is drawn out from the same end face. It is composed of an electrolytic capacitor main body and an insulating plate provided with a through hole that is disposed so as to come into contact with the end surface of the electrolytic capacitor main body from which the lead wire is drawn out, and through which the lead wire passes, and the outer surface of the insulating plate is An aluminum electrolytic capacitor, characterized in that a space portion connected to the through hole is provided in the aluminum electrolytic capacitor, and a tip end of a lead wire passing through the through hole is bent so as to fit within the space portion.