JP3683344B2 - Electrolytic capacitor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an aluminum electrolytic capacitor, and more particularly, to an electrolytic capacitor having an open mode security mechanism.
[0002]
[Prior art]
Aluminum electrolytic capacitors are widely used for consumer equipment, industrial equipment, and the like, and a typical structure thereof is shown in FIG. Capacitor element 5 in which an anode foil and a cathode foil made of aluminum foil are wound through a separator is impregnated with an electrolytic solution, and the capacitor element 5 is accommodated in metal case 4. 2 is hermetically sealed by an elastic sealing body 3 through which 2 penetrates. Conventionally, an aluminum electrolytic capacitor has a problem that the internal pressure of the aluminum case 4 is increased by hydrogen gas generated during energization. Then, due to the increase of the internal pressure, for example, a problem such as the elastic sealing body 3 jumping out with an explosion sound occurs. For this reason, a safety mechanism that releases the internal gas before the internal pressure of the aluminum case 4 becomes abnormally high due to the thin wall portion formed on the bottom side of the aluminum case 4 is used. Yes.
[0003]
[Problems to be solved by the invention]
However, since such an explosion-proof structure employs a structure that releases the internal gas, there is a problem that the electrolytic solution impregnated in the capacitor element 5 is blown out in the form of a mist when the valve is operated. To do. Here, as the electrolytic solution, a conductive one is used, and since most of the combustible materials are used, when the sprayed electrolytic solution adheres to the circuit pattern or the like, the pattern may be short-circuited, In some cases, there is a risk of ignition.
[0004]
In order to cope with such a situation, various devices have been studied that can prevent malfunctions such as short-circuiting or ignition by causing the capacitor itself to be open when an abnormality occurs in the aluminum electrolytic capacitor.
However, all of the devices that have been studied in the past only require a large space inside the capacitor, or are extremely complicated in structure, reducing the advantages of the small and inexpensive aluminum electrolytic capacitor. It was.
[0005]
Therefore, in view of the above problems, the present invention has an object to provide a small and inexpensive aluminum electrolytic capacitor having an open mode security mechanism.
[0006]
[Means for Solving the Problems]
In the present invention, an electrolytic solution is impregnated into a capacitor element 5 in which an anode foil and a cathode foil made of an aluminum foil to which electrode lead leads 2a and 2b are connected is wound through a separator, and the capacitor element 5 is attached to a metal case 4 In an electrolytic capacitor that is housed and the opening of the metal case 4 is sealed with an elastic sealing body 3,
An electrode lead with which the convex portion 12 having a hollow portion provided in the elastic sealing body 3 and the electrode holding member 11 to which the eyelet-shaped external lead electrodes 9a and 9b are fixed are in contact with each other and the weak portions 13a and 13b are provided. The external lead 1a, 1b connected to 2a, 2b is covered with the eyelet type external lead electrode 9a, 9b and protruded, and the external lead 1a, 1b is fixed to the eyelet type external lead electrode 9a, 9b. An aluminum electrolytic capacitor characterized by the following.
[0007]
The hollow eyelet-shaped external lead electrodes 9a and 9b are made of a solderable metal such as iron, copper, or brass.
[0008]
The elastic sealing body 3 is mainly composed of isobutylene, isoprene, and rubber IIR, and the elastic sealing body 3 is provided with a hollow convex portion 12 having a thin-walled portion that can be deformed to the outside by increasing the internal pressure of the case. .
[0009]
A deformation preventing protrusion 15 is provided at the center of the electrode holding member 11, and a plurality of protrusions 16 are provided on the periphery of the protrusion so as to be substantially flush with the protrusion.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
In the aluminum electrolytic capacitor according to the present invention, the convex portion 12 having a hollow portion provided in the elastic sealing body 3 is brought into contact with the electrode holding material 11 to which the eyelet-shaped external lead electrodes 9a and 9b are fixed, and the fragile portion. The external lead leads 1a and 1b connected to the electrode lead leads 2a and 2b provided with 13a and 13b are projected by covering the eyelet-type external lead electrodes 9a and 9b with the crown-type external lead electrodes 9a and 9b. External drawer leads 1a and 1b are fixed.
[0011]
The hollow eyelet-shaped external lead electrodes 9a and 9b are made of a solderable metal such as iron, copper, or brass.
[0012]
The elastic sealing body 3 is mainly composed of isobutylene, isoprene, and rubber IIR, and the elastic sealing body 3 is provided with a hollow convex portion 12 having a thin-walled portion that can be deformed to the outside by increasing the internal pressure of the case. .
[0013]
A deformation preventing protrusion 15 is provided at the center of the electrode holding member 11, and a plurality of protrusions 16 are provided on the periphery of the protrusion so as to be substantially flush with the protrusion.
[0014]
【Example】
Hereinafter, the present invention will be described with reference to the embodiments shown in FIGS.
[0015]
FIG. 1 is a sectional view of an aluminum electrolytic capacitor with a security mechanism of the present invention.
Hollow eyelet type external lead electrodes 9a and 9b are fixed to the electrode holding member 11, and lead holes 17a and 17b are provided at the tips of the lead electrodes.
Further, the external lead leads 1a and 1b are connected to the electrode lead leads (2a and 2b) provided with the weak portions (13a and 13b) for blocking the adhesion with the capacitor element.
The hollow eyelet-shaped external lead electrodes 9a, 9b of the electrode holding member 11 are crowned on the external lead leads 1a, 1b, pushed up until the hollow convex portion 12 of the elastic sealing member 3 contacts the electrode holding member 11, and the lead is drawn out. External lead leads 1a and 1b are projected from holes 17a and 17b, which are fixed to eyelet type external lead electrodes 9a and 9b to serve as external electrode terminals.
[0016]
FIG. 2 shows an electrode holding member 11 to which eyelet-shaped external extraction electrodes 9a and 9b into which electrode extraction leads can be inserted are fixed, and extraction holes (17a and 17b) are provided at the tips thereof. A capacitor body 14 is inserted into the inner surface of the electrode holding member 11.
[0017]
FIG. 3 shows an aluminum electrolytic capacitor main body using an elastic sealing body 3 provided with a deformable portion 12 that can be deformed outward by a pressure increase in the capacitor case, and electrode lead leads 2a and 2b having thin portions 13a and 13b. Other members use conventional ones.
[0018]
FIG. 4 is a perspective view of an aluminum electrolytic capacitor with a security mechanism of the present invention, in which a deformation preventing projection 15 is provided at the center of the electrode holding member 11, and a plurality of projections 16 are formed so as to be substantially flush with the projection. Therefore, when soldering the capacitor to the substrate, a space is formed between the capacitor and the flux gas generated during the soldering can be released.
[0019]
FIG. 5 is a cross-sectional view when the aluminum electrolytic capacitor with a security mechanism of the present invention is operated. The deformed portion 12 of the elastic sealing member 3 deformed outward due to the pressure increase in the capacitor case is shown in FIG. The capacitor body is displaced by the repulsive stress, tensile stress is generated in the electrode lead that is press-fixed to the electrode holding member, and the thin portions 13a and 13b provided in advance on the electrode lead are broken to open the state. Become.
[0020]
【The invention's effect】
As described above, in the aluminum electrolytic capacitor according to the present invention, when the pressure in the capacitor case increases, the deformed portion 12 of the elastic sealing body 3 pushes up the electrode holding member 11, and the electrode lead ( 2a, 2b) breaks the fragile parts (13a, 13b) to cut off the connection between the electrode lead (2a, 2b) and the capacitor element 5; therefore, when an abnormality occurs in the capacitor, the capacitor itself opens. It becomes a state, and it is possible to prevent problems such as short circuit or ignition.
Further, since the deformation preventing projection 15 is provided at the center of the electrode holding member 11, the electrode holding member 11 can be prevented from being deformed, and the peripheral portion of the deformation preventing projection 15 is substantially flush with the projection. Thus, when the capacitor is soldered to the substrate, a space is formed between the capacitor and the substrate, and flux gas generated during soldering can be released.
Accordingly, an aluminum electrolytic capacitor having a simple structure and incorporating a highly reliable safety mechanism can be provided in a small size and at a low cost.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an aluminum electrolytic capacitor with a security mechanism according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of an electrode holding member according to an embodiment of the present invention.
FIG. 3 is a cross-sectional view of an aluminum electrolytic capacitor body according to an embodiment of the present invention.
FIG. 4 is a perspective view of an aluminum electrolytic capacitor with a security mechanism according to an embodiment of the present invention.
FIG. 5 is a cross-sectional view of an aluminum electrolytic capacitor with a safety mechanism according to an embodiment of the present invention during operation.
FIG. 6 is a cross-sectional view of an aluminum electrolytic capacitor according to a conventional structure.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1a, 1b ... External extraction electrode 2a, 2b ... Electrode extraction lead 3 ... Elastic sealing body 4 ... Metal case 5 ... Capacitor element 6 ... Sleeve 7 ... Lead shoulder 8・ ・ ・ Case explosion-proof valves 9a, 9b ... Eyelet type external lead electrodes 10a, 10b ... Electrode lead lead bending fixing part 11 ... Electrode holding member 12 ... Convex parts 13a, 13b ... Electrode lead Lead thin portion 14 ... capacitor main body 15 ... deformation preventing projection 16 ... projection 17a, 17b ... lead extraction hole

Claims (4)

An electrolytic solution is impregnated in a capacitor element (5) in which an anode foil and a cathode foil made of an aluminum foil connected with electrode lead (2a, 2b) are wound through a separator, and the capacitor element (5) is placed in a metal case. In an electrolytic capacitor which is housed in (4) and the opening of the metal case (4) is sealed with an elastic sealing body (3),
The convex portion (12) having a hollow portion provided in the elastic sealing body (3) and the electrode holding material (11) to which the eyelet-shaped external lead electrodes (9a, 9b) are fixed are brought into contact with each other, and the fragile portion (13a, 13b) is projected onto the external lead (1a, 1b) connected to the electrode lead (2a, 2b) provided with the above-mentioned eyelet-shaped external lead electrode (9a, 9b). An aluminum electrolytic capacitor characterized in that the external lead (1a, 1b) is fixed to (9a, 9b). 2. The aluminum electrolytic capacitor according to claim 1, wherein the hollow eyelet-shaped external lead electrode (9a, 9b) is made of a solderable metal such as iron, copper, or brass. The elastic sealing body (3) is mainly composed of isobutylene, isoprene, and rubber (IIR), and the elastic sealing body (3) has a hollow convex portion (12) having a thin-walled portion that can be deformed to the outside by increasing the internal pressure of the case. The electrolytic capacitor according to claim 1, further comprising: A deformation preventing projection (15) is provided at the center of the electrode holding member (11), and a plurality of projections (16) are provided on the periphery of the projection so as to be substantially flush with the projection. The aluminum electrolytic capacitor according to claim 1.

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