JP2000156330A - Aluminum electrolytic capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aluminum electrolytic capacitor which can withstand vibrational stresses after the capacitor is mounted on a wiring board. SOLUTION: A highly vibration-proof aluminum electrolytic capacitor which can prevent a capacitor element 11 from vibrating in a metallic case 13 when vibrational stresses are applied to the capacitor after the capacitor is mounted on a wiring board is obtained by inserting a metallic or resin fixing bar 14 into the central part of the capacitor element 11 and, after putting the upper end section 14a of the bar 14 in a hole 12b made into the bottom face of a sealing members 12 together with lead wires 15, tightly fixing the member 12 to the case 13 by drawing the case 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum electrolytic capacitor having excellent vibration resistance after being mounted on a wiring board.

[0002]

2. Description of the Related Art FIGS. 3A to 3C are an exploded perspective view, a perspective view and a cross-sectional view showing a conventional general aluminum electrolytic capacitor. In FIGS. Is a capacitor element, and the capacitor element 1 is configured by winding an anode foil and a cathode foil (not shown) through a separator between them, and the capacitor element 1 separates the anode foil and the cathode foil from each other. The connected external lead wires 5 are drawn out in a pair. 3 is a bottomed cylindrical metal case for accommodating the capacitor element 1 together with a driving electrolyte not shown, and 2 is a pair of lead wires 5
Is a sealing member provided at the opening of the metal case 3 with a through hole 2a penetrating therethrough. The outer peripheral surface near the opening of the metal case 3 is sealed by drawing.
This constitutes an aluminum electrolytic capacitor 6.

FIG. 4 shows a state in which a conventional aluminum electrolytic capacitor 6 configured as described above is mounted on a wiring board 7. A pair of lead wires 5 of the aluminum electrolytic capacitor 6 is connected to the wiring board 7. After being inserted into the provided hole 7a, the connection is fixed by performing soldering (not shown).

[0004]

However, in such a conventional aluminum electrolytic capacitor, after the aluminum electrolytic capacitor 6 is mounted on the wiring board 7, vibration in the three-dimensional XYZ directions as shown in FIG. When stress is applied, the capacitor element 1 vibrates in the metal case 3 due to a slight gap between the inner surface of the metal case 3 and the capacitor element 1, and when excessive vibration stress is applied, the electrode foil In addition, the film at the connection portion between the lead wire 5 and the lead wire 5 may be degraded, and furthermore, the metal fatigue inside the lead wire 5 may be caused. On the other hand, in electronic components including aluminum electrolytic capacitors, in recent years, there has been a demand for an improvement in vibration resistance particularly for applications such as automotive electrical equipment.

The present invention solves such a conventional problem,
It is an object of the present invention to provide an aluminum electrolytic capacitor having excellent vibration resistance.

[0006]

According to the present invention, there is provided a fixing device in which a fixing rod made of metal or resin is inserted into the center of a capacitor element, and the upper end of the fixing rod is provided in a sealing member. Then, the sealing member is drawn together with the metal case and closed by sealing.

According to the present invention, an aluminum electrolytic capacitor resistant to vibration stress can be obtained.

[0008]

DETAILED DESCRIPTION OF THE INVENTION According to the first aspect of the present invention, a capacitor element in which an anode foil and a cathode foil are wound with a separator interposed therebetween and a driving electrolyte is impregnated, and the capacitor element is housed therein A cylindrical metal case with a bottom, a metal or resin fixing rod disposed at the center of the capacitor element, and a hole in which the upper end of the fixing rod fits, is attached to the opening of the metal case. The metal case is formed of a sealing member for sealing by drawing processing, and has an effect of being excellent in vibration resistance after mounting.

According to a second aspect of the present invention, in the first aspect, the other end of the metal or resin fixing rod is fixed or connected to the inner bottom surface of the metal case. This has the effect that the vibration resistance of the capacitor element in the case can be further improved.

According to a third aspect of the present invention, in the first or the second aspect of the present invention, the lead wire for external drawing out from the capacitor element via the sealing member is brought into close contact with the opening of the metal case. It is made into a chip-type structure by penetrating the attached insulated terminal plate and bending along the recess formed on the outer surface of this insulated terminal plate. It has the function of obtaining an aluminum electrolytic capacitor.

An embodiment of the present invention will be described below with reference to the drawings. (Embodiment 1) FIGS. 1A and 1B are an exploded perspective view showing a configuration of an aluminum electrolytic capacitor according to a first embodiment of the present invention and a perspective view of a product, respectively. In (b), reference numeral 11 denotes a capacitor element. The capacitor element 11 is formed by winding an anode foil and a cathode foil (not shown) between the anode foil and the cathode foil with a separator interposed therebetween. External lead wires 15 connected to the foil and the cathode foil, respectively, are led in a pair. Reference numeral 13 denotes a cylindrical metal case having a bottom for accommodating the capacitor element 11 together with a driving electrolyte (not shown). Reference numeral 12 denotes a through-hole 12a through which the pair of lead wires 15 pass. It is a sealing member provided.

Reference numeral 14 denotes a metal or resin fixing rod.
The fixing rod 14 is disposed at the center of the capacitor element 11, and the upper end 14 a of the fixing rod 14 fits into a hole 12 b provided on the bottom surface of the sealing member 12, and the outer peripheral surface of the metal case 13 near the opening is closed. At the time of drawing and sealing, the upper end portion 14a of the fixing rod 14 is fastened and fixed by the sealing member 12 so that the aluminum electrolytic capacitor 18 is assembled.

The metal or resin fixing rod 1
Numeral 4 may be either insertion as a core at the time of winding the capacitor element 11 or insertion after winding.
It is desirable that the outer surface of 4 and the internal member of capacitor element 11 be in close contact with each other. The fixing rod 14 may be made of metal or resin. However, when metal is used, the innermost member of the capacitor element 11, that is, the surface in contact with the fixing rod 14 must be a separator. In addition, fixed rod 1
It is necessary to select a material 4 that is not affected by the driving electrolyte.

(Embodiment 2) FIGS. 2A to 2D are an exploded perspective view showing a structure of an aluminum electrolytic capacitor according to a second embodiment of the present invention and a perspective view of a product, respectively. The difference from the first embodiment shown in FIG. 1 is that the lower end of the fixing rod is fixed to the inner bottom surface of the metal case, and the other configuration is the same as that of the first embodiment. is there.

That is, in FIGS. 2 (a) to 2 (d),
Reference numeral 14 denotes a fixing rod made of metal or resin. After the lower end 14b of the fixing rod 14 is fixed to the inner bottom surface 13a of the metal case 13, the capacitor element 11 is inserted into the metal case 13, and the metal The aluminum electrolytic capacitor 19 is formed by tightening and fixing the upper end portion 14a of the fixed rod 14 by drawing and sealing the case 13, and the fixed rod 1
The vibration resistance of the capacitor element 11 can be further improved because the both end portions 14a and 14b of the capacitor element 4 are fixed.

The lower end 14b of the fixing rod 14 is fixed to the inner bottom surface 13a of the metal case 13 by:
The method of bonding by ultrasonic connection or laser welding using the metal fixing rod 14 is the most stable from the viewpoint of strength, and an excellent effect can be obtained.

The thus constructed aluminum electrolytic capacitors according to the first and second embodiments of the present invention are mounted on a wiring board, and XY-
In the three-dimensional direction of Z, amplitude 7.5 mm, vibration acceleration 30
G, Table 1 shows the results of a vibration test in which vibration was applied under vibration conditions of a frequency of 10 to 400 Hz.

[0018]

[Table 1]

As is clear from Table 1, the aluminum electrolytic capacitor according to the present invention is very little affected by vibration and can exhibit stable performance.

In the above embodiment, a lead wire type aluminum electrolytic capacitor in which a lead wire is inserted and mounted on a wiring board has been described as an example. After that, it is needless to say that the present invention can be similarly applied to a chip type aluminum electrolytic capacitor which is bent along the concave portion on the outer surface of the insulating terminal plate.

[0021]

As described above, in the aluminum electrolytic capacitor according to the present invention, the fixing rod is disposed at the center of the capacitor element, and at least the upper end of the fixing rod is fixed with the sealing rubber. This makes it possible to obtain an aluminum electrolytic capacitor having extremely small deterioration in characteristics with respect to vibration stress after mounting on the substrate and having excellent vibration resistance.

[Brief description of the drawings]

FIG. 1A is an exploded perspective view showing a configuration of an aluminum electrolytic capacitor according to a first embodiment of the present invention; FIG.

FIG. 2A is an exploded perspective view of a metal case and a fixing rod showing the configuration of an aluminum electrolytic capacitor according to a second embodiment of the present invention. FIG. 2B is an exploded perspective view of the capacitor element and the metal case. Exploded perspective view of a metal case containing a capacitor element and a sealing member (d) Perspective view of the completed product

FIG. 3 (a) is an exploded perspective view showing a configuration of a conventional aluminum electrolytic capacitor. FIG. 3 (b) is a perspective view.

FIG. 4 is a cross-sectional view showing a state where an aluminum electrolytic capacitor is mounted on a wiring board.

FIG. 5 is a perspective view showing a state of a vibration test of the aluminum electrolytic capacitor mounted on the wiring board;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Capacitor element 12 Sealing member 12a Through-hole 12b Hole 13 Metal case 13a Inner bottom surface of metal case 14 Fixing rod 14a Upper end 14b Lower end 15 Lead wire 18, 19 Aluminum electrolytic capacitor

Claims (3)

[Claims] 1. A capacitor element impregnated with a driving electrolyte by winding an anode foil and a cathode foil therebetween with a separator interposed therebetween, a bottomed cylindrical metal case for housing the capacitor element, and A metal or resin fixing rod provided in the center, and a sealing hole having a hole into which the upper end of the fixing rod fits, which is attached to an opening of the metal case and which is sealed by drawing the metal case. Aluminum electrolytic capacitor made of components. 2. The aluminum electrolytic capacitor according to claim 1, wherein the other end of the metal or resin fixing rod is fixed or connected to the inner bottom surface of the metal case. 3. A lead wire for external lead-out led from a capacitor element via a sealing member is passed through an insulating terminal plate which is attached in close contact with an opening of a metal case, and an outer surface of the insulating terminal plate. 3. The aluminum electrolytic capacitor according to claim 1, wherein the aluminum electrolytic capacitor has a chip-shaped structure by being bent along a concave portion formed in the aluminum electrolytic capacitor.