JPH03215925A - Electrolytic capacitor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention includes a capacitor element, a cylindrical metal case with a bottom that houses the capacitor element, and a sealing body that seals an opening of the metal case. The present invention relates to electrolytic capacitors.

2. Description of the Related Art A conventional electrolytic capacitor of this type has a structure as shown in FIG. That is, a bottomed cylindrical metal case 2 that houses the capacitor element 1, a sealing rubber 3 that seals the opening of the metal case 2, a temporary seal 4, and a lead wire 5 led out from the capacitor element 1. The metal case 1 is provided with a lead terminal 6 connected to the
An explosion-proof valve 7 was provided at the bottom of the tank.

However, in this configuration, since the explosion-proof valve 7 is provided at the bottom of the metal case 1, there is a risk of secondary disasters due to ignition due to short circuit or gas spouting. As shown in the publication, an electrolytic capacitor with a safety device as shown in FIG. 6 has been proposed.

That is, in the electrolytic capacitor shown in FIG. 6, a capacitor element 8 is positioned and fixed in a metal case 9 by a fixing agent 10 made of resin, and the capacitor element 8 has a bottom so as to be in contact with at least one side surface of the capacitor element 8. A cylindrical inner case 11 is placed over the capacitor element 8 to form a space 12 between the end face of the capacitor element 8 and the bottomed part 11a of the inner case 11, and a pair of lead wires 13.
13a, and the pair of lead wires 13.
13a is a pair of lead terminals 14 located outside the metal case 9. 14a, and the pair of lead wires 13. 13a, an electrical contact portion 15 made of a lead wire is provided in the middle of one lead wire 13, and the bottomed portion 1 of the inner case 11 is provided so as to face the electrical contact portion 15.
1a is provided with a safety valve 16 made of rubber, and when the internal pressure of the inner case 11 increases in an abnormal situation, this safety valve 1
6 is pushed up by the internal pressure to cut and open the electrical contact portion 15 made of the lead wire, thereby interrupting the current.

However, the above-mentioned conventional electrolytic capacitor with a safety device has a structure in which only the safety valve 16 made of rubber cuts and opens the electrical contact part 15 made of a lead wire to interrupt the current, so the safety valve 16 made of rubber does not have a glue. In this case, since this type of electrolytic capacitor does not have an explosion-proof valve in the metal case 9, the internal pressure will increase rapidly in the event of an abnormality, and the electrolytic capacitor will eventually explode. This has the problem of causing damage to other electronic components.

In addition, this safety device-equipped electrolytic capacitor has a double case configuration consisting of a metal case 9 and an inner case 11, so the outer diameter and height of the electrolytic capacitor itself are larger than conventional electrolytic capacitors with anti-fan valves. Become a thing,
Moreover, since the internal configuration is vastly different from conventional electrolytic capacitors with explosion-proof valves, not only can existing parts not be reused, but the construction method itself must also be changed, which is extremely unreasonable from a cost perspective. Met.

In order to solve these problems, the inventors of the present invention have made various studies and have developed an electrolytic capacitor with a safety device as shown in FIG.

That is, the electrolytic capacitor with a safety device shown in FIG. 7 includes a capacitor element 21, a cylindrical metal case 22 with a bottom that houses the capacitor element, and a sealing body 23 that seals the opening of the metal case 22. A terminal plate 25 is arranged inside the metal case 22 via a reinforcing member 24 made of hard resin separately from the sealing body 23, and a pair of terminals led out from the capacitor element 21 are attached to the terminal plate 25. A pair of lead plates 28. which are electrically connected to the lead wires 26.26a and connected to the external lead terminals 2727a. 28a, and this pair of lead plates 28
．． 28a, one lead plate 28, and a pair of lead wires 26 led out from the capacitor element 21. 2
An electrical contact part 29 made of a lead wire that has a thin part between it and one of the lead wires 6a in A safety device 30 is provided to cut off the current, and this safety device 30 includes a rubber valve 31 and a rubber valve 3.
1, and cuts the thin-walled portion 29 of the electrical contact portion. Alternatively, it was constructed with a cut piece 32 made of hard resin.

Problems to be Solved by the Invention However, in the conventional electrolytic capacitor with a safety device shown in FIG. 7, the safety device 30 requires a cut piece 32 and a garbage valve 31 made of ceramic or hard resin. Not only does this increase the number of times, but it is also difficult to work with and is unreasonable in terms of cost.

The present invention solves these problems, and aims to provide an electrolytic capacitor that reduces the number of parts, improves workability, and has the same effects as conventional electrolytic capacitors with safety devices. It is something to do.

Means for Solving the Problems In order to achieve the above objects, the electrolytic capacitor of the present invention has the following features:
A safety device is provided in which when internal pressure rises in the event of an abnormality, a terminal board installed inside a metal case and equipped with a cranock expands, thereby opening the electrical contact and interrupting the current.

Effect According to the above configuration, when an abnormality occurs, the terminal board with the crack that constitutes the safety device swells due to the increase in internal pressure of the metal case, and this bulge breaks the electrical contact part and disconnects the electrical contact. Since the section can be opened and the current can be cut off, the safety device can be operated reliably without gas leaking to the outside.

Embodiment Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings. In FIGS. 1 to 3, a capacitor element 41 is placed inside a metal case 42 made of aluminum in a cylindrical shape with a bottom and a fixing agent 43 made of resin.
The position is fixed by. The opening of the metal case 42 is sealed with a sealing member 46 made of a sealing rubber 44 and a sealing plate 45 made of Bakelite l. A terminal plate 48 is disposed within the metal case 42. A crack 49 is provided on this terminal plate 48, and a pair of lead plates 50. 50a, and this pair of lead plates 50. One end of 50a is connected to a pair of external lead terminals 51, 51a attached to the sealing body 46 by caulking. Further, the pair of leads 50. 50a, a pair of lead wires 52.50a led out from the capacitor element 41 is provided at the other end of the other lead plate 50a. Among the lead wires 50a, the other lead wire 52a is connected by caulking. moreover,
The terminal plate 48 includes a pair of lead plates 50. A separate lead plate 53 is attached between the capacitor elements 41 and 50a, and at the other end of the lead plate 53, a pair of lead wires 52. Among the lead wires 52a, one lead wire 52 is connected by caulking.

Further, the pair of lead plates 50. Between one lead plate 50 in 50a and the other end of a separate lead plate 53, an electrical contact part 54 made of a lead wire is attached by bonding, and this electrical contact part 54 has a wire as shown in FIG. The thin wall portion 55 is formed as shown in FIG.

A safety device 56 constituted by a terminal plate 48 provided with the crack 49 and an electrical contact portion 54 made of a single lead wire provided with a thin wall portion 55 is configured to protect the metal case 42 in the event of an abnormality.
As shown in FIG. 3, when the pressure inside the metal case 42 increases abnormally, the terminal board 48 has a crack 49, so the terminal board 48
swells and breaks the thin wall portion 55 of the electrical contact portion 54. In this case, there is a risk that the terminal board may crack and gas will blow out, but the opening of the metal case 42 is
Because it is sealed, there is no risk of gas blowing out to the outside, and the sealing body 46 prevents the safety device 56 from being exposed to the outside, so this electrolytic capacitor can also be used as a board-standing type. can do.

In the above embodiment, the electrical contact portion 54 is made of a lead wire, but as shown in FIG. 4, the electrical contact portion 54' may be made of Ag or Cu paste. It has the same effect as the embodiment. In this FIG. 4, the other configurations are the same as in the above embodiment.

Effects of the Invention As is clear from the description of the embodiments above, in the electrolytic capacitor of the present invention, the terminal plate provided in the metal case and provided with cracks swells due to an increase in internal pressure during abnormal conditions, causing the electrical contact to swell. The electrolytic capacitor with a safety device is equipped with a safety device that interrupts the current by opening the terminal board, and this safety device consists of a crack provided on the terminal board and the electrical contact section. Compared to the conventional method, it is possible to reduce the number of parts and improve workability, and it is also extremely cost effective.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view of an electrolytic capacitor showing an embodiment of the present invention, Fig. 2 is a cross-sectional view taken along the line A-A' in Fig. 1, and Fig. 3 is a state in which the safety device of the electrolytic capacitor is in operation. FIG. 4 is a vertical cross-sectional view of an electrolytic capacitor showing another embodiment of the present invention, FIG. 5 is a vertical cross-sectional view of an electrolytic capacitor showing a conventional example, and FIG. 6 is a vertical cross-sectional view of another conventional example. FIG. 7 is a vertical cross-sectional view showing an electrolytic capacitor with a safety device at the development stage of the present invention. 41...Capacitor element, 42...Metal case, 44...Sealing logo, 45...
・Hake plate, 46... Sealing body, 47...
・Reinforcement member, 48...Terminal board, 49...
・Crack, 50. 50a...a pair of lead plates, 51. 51a... External lead terminal, 52. 52a...Pair of lead wires, 54
．． 54'... Electric contact section, 56...
Safety device.

Claims (1)

[Claims] It comprises a capacitor element, a bottomed cylindrical metal case containing the capacitor element, and a sealing body that seals the opening of the metal case. A terminal board with a crack is arranged inside the metal case, and a pair of leads are electrically connected to the pair of lead wires led out from the capacitor element and connected to an external lead terminal. attaching a plate, and providing an electrical contact portion between one lead plate of the pair of lead plates and one lead wire of the pair of lead wires led out from the capacitor element,
Furthermore, the electrolytic capacitor is provided with a safety device that opens the electrical contact portion and cuts off the current when the terminal plate provided with the crack swells as the internal pressure increases in the event of an abnormality.