JPH03215926A - Aluminum electrolytic capacitor - Google Patents

Abstract

PURPOSE:To prevent the gas of a driving electrolyte from running out of an aluminum electrolytic capacitor by a method wherein, when an abnormal voltage higher than the rated voltage is impressed, an electric circuit is cut off by actuating a safety device through the intermediary of a temperature-sensing switch. CONSTITUTION:A dielectric oxide film is formed on the rough surface of an aluminum foil while a capacitor element comprising the aluminum foil wound up together with a separator is sealed up in an aluminum case 5 together with a driving electrolyte. Next, a safety device 3 comprising a fuse or a breaker, etc., is connected to one electrode terminal 2 out of a pair of electrode terminals 2, 2a provided on an electrolytic capacitor main body 1. Furthermore, a temperature-sensing switch 4 such as a make-type temperature sensing reed switch or a bimetal, etc., is built-in the aluminum case 5 wherein the capacitor element is sealed up. Through these procedures, since the electric circuit can be cut off before the safety device 3 such as explosion-proof valve, etc., installed in the metallic case is actuated, the driving electrolyte can be prevented from running out of the electrolytic capacitor.

Description

[Detailed description of the invention] Industrial applications The present invention relates to an aluminum electrolytic capacitor.

Conventional technology Conventional aluminum electrolytic capacitors are made by forming a dielectric film on roughened aluminum foil, winding this aluminum foil together with a separator to form a capacitor element, and impregnating this capacitor element with a driving electrolyte. At the same time, the capacitor element was enclosed in an aluminum case.

If this aluminum electrolytic capacitor is used at a higher temperature or higher voltage than the rated value, the temperature of the driving electrolyte rises and vaporizes, causing the internal pressure of the aluminum case to rise. If Fukuroka exceeds,
Will the capacitor element come off the aluminum case and pop out?
Or, conversely, the aluminum case may fly away,
It is extremely dangerous.

Normally, aluminum electrolytic capacitors have a safety device by providing a weak point in the sealing material or aluminum case, and if the internal pressure of the aluminum case suddenly increases, the weak point in the aluminum case will break. Because the gas from the driving electrolyte escapes, a large explosion does not occur.

Problems to be Solved by the Invention However, with the conventional safety device described above, gas from the drive electrolyte escapes outside the aluminum electrolytic capacitor, which can stain the inside of the device and is indistinguishable from smoke from a fire. There was a problem.

An object of the present invention is to provide an aluminum electrolytic capacitor that solves these problems.

Means for Solving the Problems In order to solve the above-mentioned conventional problems, the present invention provides an aluminum electrolytic capacitor main body having a pair of electrode terminals, and an aluminum electrolytic capacitor body having an aluminum electrolytic capacitor main body having a pair of electrode terminals, and an aluminum electrolytic capacitor main body having an aluminum electrolytic capacitor body having a pair of electrode terminals. A make-type temperature-sensitive switch is connected between the pair of electrode terminals, and the temperature-sensitive switch is built into an aluminum case in which a capacitor element is housed.

Function The make-type temperature-sensitive switch with the above configuration has its contacts turned off below a certain set temperature.
Since it has the characteristic of turning ON when the temperature rises above that level, if an abnormal voltage is applied to the aluminum electrolytic capacitor, the leakage current increases and internal heat generation increases, causing the temperature of the capacitor 4 element to rise. When this temperature rises above a certain temperature, the temperature-sensitive switch changes from OFF to ON.

As a result, a large current flows through the temperature-sensitive switch to the safety device connected to one electrode terminal, and the safety device can be operated, for example, the fuse can be blown to interrupt the electric circuit. In this case, the operation of the thermostatic switch occurs instantaneously, and the electric circuit is cut off before a safety device such as an explosion-proof valve installed in the metal case is activated, so that the driving electrolyte flows into the aluminum electrolytic capacitor. It is possible to prevent leakage to the outside.

EXAMPLE Hereinafter, an example of the present invention will be described based on the accompanying drawings. In the figure, 1 is an aluminum electrolytic capacitor body, and this aluminum electrolytic capacitor body 1 has a capacitor element formed by forming a dielectric oxide film on the surface of roughened aluminum foil and winding this together with a separator. The capacitor element is sealed together with a driving electrolyte in an aluminum case. Reference numerals 2 and 2a denote a pair of electrode terminals provided on the aluminum electrolytic capacitor body 1. Of the pair of electrode terminals 2 and 2a, one electrode terminal 2 is connected to a safety device 3 such as a fuse or breaker. . Reference numeral 4 denotes a make-type temperature-sensitive reed switch or a high-metal temperature-sensitive switch connected between the pair of electrode terminals 2.2a, and the temperature-sensitive switch 4 is built in an aluminum case 5 containing a capacitor element. There is.

Next, the 250 V 33 used in the input circuit of the power supply
A 0 μF aluminum electrolytic capacitor element is prepared as a sample, a temperature-sensitive switch 4 consisting of a make-type thermal reed switch with an operating temperature of 110°C is connected between a pair of electrode terminals 2 and 2a, and this is wound. It is enclosed in an aluminum case 5 together with the capacitor element. When an abnormal voltage of 360 µm was applied to this aluminum electrolytic capacitor, the leakage current increased and the internal temperature rose dramatically. After 90 seconds, the internal temperature reached 110°C, and the temperature-sensitive switch 4 was turned from OFF to ON. At that moment, a large current flowed through the temperature-sensitive switch 4, blowing out the fuse or breaker constituting the safety device 3, and cutting off the electric circuit. In this case, the internal pressure of the aluminum case 5 increases and the electric circuit is cut off before the explosion-proof valve installed in the aluminum case 5 operates, causing the gas of the driving electrolyte to leak out of the aluminum electrolytic capacitor. There is no such thing.

In the above embodiment, a temperature-sensitive reed switch is used as the temperature-sensitive switch 4, but similar results can be obtained with other make-type thermostatic switches such as Himekuru.

Effects of the Invention As is clear from the description of the embodiments above, the aluminum electrolytic capacitor of the present invention operates a safety device via a temperature-sensitive switch to interrupt the electrical circuit when an abnormal voltage higher than the rated voltage is applied. Since the aluminum electrolytic capacitor is shifted, the gas of the driving electrolytic solution can be prevented from flowing out to the outside of the aluminum electrolytic capacitor.

[Brief explanation of drawings]

FIG. 1 is an electrical circuit diagram showing an aluminum electrolytic capacitor according to an embodiment of the present invention in which a safety device and a temperature-sensitive switch are connected. 1... Aluminum electrolytic capacitor body, 2, 2a.
...Pair of electrode terminals, 3...Safety device, 4...
...Temperature-sensitive switch, 5...Aluminum case.

Claims (1)

[Claims] It has an aluminum electrolytic capacitor main body having a pair of electrode terminals, a safety device connected to one of the pair of electrode terminals, and a make type temperature sensitive switch between the pair of electrode terminals. This is an aluminum electrolytic capacitor characterized by a temperature-sensitive switch built into an aluminum case in which the capacitor element is housed.