JPH10242012A - Electrolytic capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrolytic capacitor wherein, when a terminal plate provided in a case is expanded because the pressure in a metal case rises to abnormal level, the supply of electric current to an electrolytic capacitor is surely cut off to stop rising of the pressure in the metal case, so that possibility of gas blowout outside the metal case is prevented. SOLUTION: The capacitor comprises projections 2 and 2a and projections 3 and 3a comprising inclined terminal surface provided, individually, while facing on the same axis between a opening-sealing plate 5 and a terminal plate 18, and lead plates 10 and 10a inserted in the interval between facing projections. Here, dislocation in facing projections 2 and 3, and projections 2a and 3a when the terminal plate 18 expands cuts the lead plates 10 and 10a, so that the supply channel of current to the capacitor is cut off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolytic solution in which a capacitor element is housed in a bottomed cylindrical metal case, the opening of the metal case is sealed with a sealing plate, and an internal sealing plate is provided inside the sealing plate. It relates to a capacitor.

[0002]

2. Description of the Related Art A conventional electrolytic capacitor of this type is shown in FIG. In FIG. 5, a capacitor element 41 formed by winding a resin-made anti-winding tape 40 is impregnated with an electrolytic solution and housed in a bottomed cylindrical aluminum metal case 42,
It is positioned and fixed by the fixing agent 43. Metal case
The opening of 42 is closed by a cylindrical sealing plate 45 such as bakelite in which an annular sealing rubber 44 is arranged on the upper peripheral edge. The sealing plate 45 is integrally provided with a pair of external lead-out terminals 51 and 51a penetrating vertically. An annular reinforcing member 47 made of hard resin is provided separately from the sealing plate 45.
A terminal plate 48 functioning as an internal sealing plate is disposed in the metal case 42 through the terminal. The terminal plate 48 is provided with three relay terminals 53, 53a, 53b integrally penetrating up and down and cracks in a V-shaped groove crossing substantially the center of the lower surface in a straight line.
49 are provided. Relay terminals 53, 53 provided on the terminal plate 48
b, a pair of lead plates 50, 50a is attached to each upper part, and one end of the pair of lead plates 50, 50a is caulked to each lower part of a pair of external lead terminals 51, 51a provided on the sealing plate 45. It is connected. A pair of lead wires 52, 52a led from the capacitor element 41 are connected to the relay terminals 53, 53a by caulking, respectively. Also, the relay terminal
The lead 54 is joined between the upper part of the terminal 53a and the upper part of the relay terminal 53b. Terminal plate 48 with cracks 49 and leads 54
Constitutes a safety device.

[0003] This safety device is a metal case at the time of abnormality.
When the pressure inside the metal case 42 rises abnormally as shown in FIG. 6, the terminal plate 48 functioning as an internal sealing plate has a crack 49. 48 swells and cuts the lead 54, and the terminal plate 48
Is broken and gas is ejected to the outside of the terminal plate 48, but the opening of the metal case 42 is closed by the sealing plate 45, and the supply of current to the electrolytic capacitor is cut off by cutting the lead 54, The risk of gas blowing out of the metal case 42 is prevented.

[0004]

A safety device comprising a terminal plate 48 as an internal sealing plate and a lead 54 shown in FIG.
When the pressure inside the metal case 42 rises abnormally,
The swelling alone does not cut the lead 54, and the lead 54 cuts when the terminal plate 48 breaks at the crack 49, so that the pressure inside the metal case 42 becomes extremely high, so that the outside of the terminal plate 48 It is necessary to increase the volume of the space between the terminal plate 48 and the sealing plate 45 in order to relieve the pressure inside the metal case 42 when the gas is blown out, which causes a problem that the electrolytic capacitor is unnecessarily increased in size. is there.

When the pressure inside the metal case 42 is abnormally increased and the terminal plate 48 expands, the lead 54 may come off from the terminal plate 48 near the lead plate 50a.
Even if the supply of current to the electrolytic capacitor is temporarily cut off by cutting the lead 54, the lead 54 that has peeled off when the swelling of the terminal
a and the relay terminal 53b, and as a result, the lead 54 may be short-circuited to the lead plate 50a. As a result, the supply of current to the electrolytic capacitor is resumed and the metal case 42
The internal pressure is further increased, and the sealing plate 45 at the opening of the metal case 42 is also damaged, which may cause an explosion.

According to the present invention, when the pressure inside the metal case is abnormally increased and the terminal plate functioning as an internal sealing plate arranged inside the case expands, the supply of current to the electrolytic capacitor is reliably cut off. It is an object of the present invention to provide an electrolytic capacitor in which a rise in pressure in a case is stopped to prevent a risk of gas ejection to the outside of a metal case.

[0007]

According to an electrolytic capacitor of the present invention, the capacitor element is housed in a cylindrical metal case having a bottom and the opening of the metal case is sealed with a first sealing plate. A second sealing plate is provided inside the plate, and a pair of projections having inclined end surfaces are provided on each sealing plate so as to be coaxially opposed to each other to supply current to a pair of lead wires led out from the end surface of the capacitor element. The lead plate is inserted into the gap between the opposed protrusions, and the lead plate is cut by the movement of the opposed protrusions caused by expansion of the second sealing plate due to an increase in internal pressure at the time of an abnormality, thereby cutting the lead plate. The first feature is to cut off a current supply path.

In the electrolytic capacitor according to the present invention, the capacitor element is housed in a bottomed cylindrical metal case, and the opening of the metal case is sealed with a first sealing plate. A second sealing plate is provided, and the first block and the second block are joined by a lead plate that supplies a current to a pair of lead wires led out from an end face of the capacitor element. Disposing between the sealing plates, cutting the lead plate by the movement of the two blocks due to the swelling of the second sealing plate due to the internal pressure rise at the time of abnormality, and interrupting the current supply path to the lead wire. 2.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings shown in FIGS. FIG. 1 is a cross-sectional view showing a first embodiment of the electrolytic capacitor of the present invention, and FIG. 2 is a cross-sectional view showing a state in which the safety device operates due to abnormally high pressure in the metal case in the electrolytic capacitor of the same embodiment. is there. Further, in FIG. 2, the same reference numerals as those in FIG. 1 indicate the same components.

In FIG. 1, a capacitor element 11 formed by winding both electrode foils through an electrolytic paper and winding a resin-made winding tape 6 is impregnated with an electrolytic solution to form a bottomed cylindrical aluminum material. It is housed in a metal case 12 and positioned and fixed by a resin fixing agent 7. Metal case 12
Is sealed by a sealing plate 5 made of phenol or the like in which an annular sealing rubber 4 is arranged on the upper peripheral edge. Sealing plate 5
A pair of cylindrical projections 2 and 2a having inclined end surfaces are provided upright at a predetermined distance from each other. The pair of external lead-out terminals 1 and 1a are provided integrally with the sealing plate 5 so as to pass through the inside of the pair of protrusions 2 and 2a from the upper surface of the sealing plate 5, respectively. A metal case at a position separated from the sealing plate 5 by a predetermined distance
A terminal plate 18 functioning as an internal sealing plate is hermetically housed in 12. A pair of relay terminals 1 that penetrate up and down the terminal plate 18
3, 13a are provided integrally.

As shown in the figure, a pair of cylindrical projections 3 and 3a having inclined end surfaces are erected on the upper surface of the terminal plate 18 at predetermined intervals, and a pair of projections 2 and 2a of the sealing plate 5 are provided.
The end face of the projection 2 and the end faces of the pair of projections 3 and 3a of the terminal plate 18 are coaxially opposed to each other.
And the end face of the projection 2a and the end face of the projection 3a are arranged substantially in parallel. Relay terminal 1 provided on terminal plate 18
A pair of lead plates 10, 10a each made of a rectangular aluminum wire are attached to one upper end of each of the upper portions 3, 3a. The lead plate 10 is inserted into a gap formed between the end face of the projection 2 and the end face of the projection 3 disposed coaxially and facing each other between the sealing plate 5 and the terminal plate 18. Is inserted into a gap formed between the end face of the projection 2a and the end face of the projection 3a. The other ends of the pair of lead plates 10 and 10a are connected to a pair of external lead terminals 1 attached to the sealing plate 5,
1a is connected to each lower portion by means such as caulking or welding. A pair of lead wires 8 and 8a led from the capacitor element 11 are connected to the lower portions of the relay terminals 13 and 13a by caulking or welding. The projections 2 and 3 and the projections 2a and 3a, which are disposed coaxially facing each other between the sealing plate 5 and the terminal plate 18, and the leads inserted into the respective gaps formed between the pair of opposed projections. The plates 10, 10a constitute a safety device.

The safety device shown in FIG. 1 operates by increasing the pressure in the metal case 12 at the time of an abnormality. When the pressure in the metal case 12 becomes abnormally high as shown in FIG. 2, it functions as an internal sealing plate. Between the end surfaces of the protrusions 2 and 3 and the end surfaces of the protrusions 2a and 3a, which are coaxially arranged between the sealing plate 5 and the terminal plate 18 so as to face each other. The lead plates 10 and 10a inserted into the respective gaps formed in the above are cut. Since the current supply path to the electrolytic capacitor is cut off by cutting the lead plates 10 and 10a, the pressure rise in the metal case 12 stops and the metal case 12
The danger of gas ejection to the outside of the vehicle is prevented.

Next, another embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIGS. 4A and 4B and FIGS. 4A and 4B. FIG. 3A is a sectional view showing a second embodiment of the electrolytic capacitor of the present invention, and FIG. 3B is a perspective view of the joining block 33 shown in FIG. FIG.
FIG. 4A is a cross-sectional view showing a state in which the pressure in the metal case is abnormally high and the safety device is operated in the electrolytic capacitor of the embodiment, and FIG. 4B is a joining block shown in FIG. 34 is a perspective view of FIG. 4 (a) and 4 (b), which are the same as those in FIGS. 3 (a) and 3 (b).

3 (a) and 3 (b), the electrode foils of both electrodes are wound through an electrolytic paper to form a resin-made tape.
The capacitor element 31 formed by winding the coil 26 is impregnated with an electrolytic solution, housed in a bottomed cylindrical aluminum metal case 32, and positioned and fixed by a resin fixing agent 27. The opening of the metal case 32 is closed by a sealing plate 25 made of phenol or the like in which an annular sealing rubber 24 is arranged on the upper peripheral edge. The sealing plate 5 is integrally provided with a pair of external lead terminals 21 and 21a penetrating vertically. The peripheral edge of the lower surface of the sealing plate 25 projects annularly to form an annular guide 35. Also,
The annular end face of the annular guide 35 further protrudes at the center, and an annular projection 34 is formed along the end face of the annular guide 35. A block 33a is provided on the lower surface of the sealing plate 25 in the annular guide 35.
Are fixed to the sealing plate 25 by adhesion, adhesion or the like. (The block 33a may be formed integrally with the sealing plate 25.)

The base of the terminal plate 28 is made of bakelite, and rubber 30 is attached to the entire upper surface of the base. The terminal plate 28 is hermetically housed in the metal case 12 below the sealing plate 5 with the annular projection 34 of the sealing plate 5 biting into the rubber 30 on the upper surface. In the annular guide 35 on the upper surface of the terminal plate 28, a block 33b is fixed to the terminal plate 28 by adhesion, adhesion or the like. (This block 33b is a terminal plate
28 may be formed by integral molding). The two blocks 33a and 33b are joined by a lead 20 made of a rectangular aluminum wire having a predetermined length to form a joining block 33.
Is composed. The terminal plate 28 is provided with a pair of relay terminals 23 and 23a integrally penetrating vertically.

One end of each of lead plates 22 and 22b made of a rectangular aluminum wire is mounted on each of the relay terminals 23 and 23a. The other end of the lead plate 22b is connected to one end of the lead 20, and the other end of the lead 20 is connected to a lead plate 22a made of a rectangular aluminum wire. The other end of the lead plate 22a is connected to a lower portion of the external lead-out terminal 21a attached to the sealing plate 25 by means such as caulking or welding. The other end of the lead plate 22 is connected to the lower part of the external lead-out terminal 21 attached to the sealing plate 25 by means such as caulking or welding. Further, a pair of lead wires 29, 29a led from the capacitor element 31 are connected to the lower portions of the relay terminals 23, 23a, respectively, by means such as caulking or welding. Lead 20 and two blocks 33a, 33b
The joining block 33 which is joined together constitutes a safety device.
In the second embodiment, a configuration is adopted in which the leads 20 are arranged only on one surface of the joining block 33. However, another lead (not shown) is attached to a surface of the joining block 33 facing the surface on which the leads 20 are arranged. Leads may be arranged on both sides of the block 33. In this case, the lead plate 22 may be divided into two parts, one of the two parts may be connected to one end of the lead, and the other part of the lead plate 22 may be connected to the other end of the lead.

The safety device shown in FIG. 3B operates by increasing the pressure in the metal case 32 at the time of an abnormality, and the pressure in the metal case 32 abnormally increases as shown in FIG. And the terminal plate 28 functioning as an internal sealing plate swells, and the two blocks 33a in the joining block 33,
By the movement of 33b, the position where the two are joined shifts and the lead 20 is cut. Since the supply path of the current to the electrolytic capacitor is cut off by cutting the lead 20, the pressure increase in the metal case 32 is stopped, and the risk of gas ejection to the outside of the metal case 32 is prevented. In the second embodiment, as compared with the first embodiment, since the joining block arranged between the two sealing plates is arranged near the center of the sealing plate, the terminal plate 28 functioning as an internal sealing plate is provided. It acts even on a slight swelling, further improving safety.

[0018]

The electrolytic capacitor of the present invention is provided with a safety device for interrupting a current supply path to the electrolytic capacitor when a terminal plate functioning as an internal sealing plate expands due to a pressure rise in the metal case at the time of abnormality. ing.

In the first safety device, a pair of projections 2, 2a, 3, 3a having inclined end faces are provided one by one on the sealing plate 5 and the terminal plate 18 functioning as an internal sealing plate. Each of the lead plates 10, 10a is inserted into each gap, and the lead plates 10, 10a are cut when the terminal plate is expanded. The second safety device is composed of a joining block in which two blocks 33a and 33b are joined by using a lead 20 for supplying a current to a lead wire led out from an end face of the capacitor element, and when the terminal plate expands. When the two blocks 33a and 33b forming the joining block 33 are moved, the joining position of the two blocks shifts and the lead 20 is cut.

Therefore, the safety device operates due to the pressure increase in the metal case at the time of abnormality and the current supply path to the electrolytic capacitor is interrupted, so that the pressure increase in the metal case stops without damaging the terminal plate, Excellent effects are obtained, such as the risk of gas emission to the outside of the metal case is prevented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of the electrolytic capacitor of the present invention.

FIG. 2 is a sectional view showing an operation state of the safety device when the electrolytic capacitor of FIG. 1 is abnormal.

FIG. 3 (a) is a sectional view showing a second embodiment of the electrolytic capacitor of the present invention. (B) is a perspective view of the joining block shown in (a).

FIG. 4A is a cross-sectional view illustrating an operation state of the safety device when the electrolytic capacitor of the second embodiment is abnormal.
(B) is a perspective view of the joining block shown in (a).

FIG. 5 is a sectional view of a conventional electrolytic capacitor.

FIG. 6 is a cross-sectional view showing an operation state of a safety device when a conventional electrolytic capacitor is abnormal.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1a External lead-out terminal 2, 2a protrusion 3, 3a protrusion 4 Sealing rubber 5 Sealing plate 6 Winding tape 7 Fixing agent 8, 8a Lead wire 10, 10a Lead plate 11 Capacitor element 12 Metal case 13, 13a Relay terminal 20 Lead 21, 21a External lead-out terminal 22, 22a Lead plate 23, 23a Relay terminal 24 Sealing rubber 25 Sealing plate 26 Retaining tape 27 Fixing agent 29, 29a Lead wire 30 Rubber 31 Capacitor element 32 Metal case 33 Joining block 34 Projection 35 Ring guide

Claims (2)

[Claims] 1. An electrolytic capacitor in which a capacitor element is housed in a bottomed cylindrical metal case, and an opening of the metal case is sealed with a first sealing plate, wherein a second sealing plate is provided inside the sealing plate. A pair of protrusions having inclined end faces are provided on each sealing plate, and are arranged coaxially opposite each other, and a lead plate for supplying current to a pair of lead wires derived from the end faces of the capacitor element is provided with a gap between the opposed protrusions. The second sealing plate expands due to an increase in internal pressure at the time of an abnormality, the lead plate is cut by the movement of the opposite projection due to the expansion of the second sealing plate, and a current supply path to the lead wire is cut off. Electrolytic capacitor to do. 2. An electrolytic capacitor in which a capacitor element is housed in a bottomed cylindrical metal case, and an opening of the metal case is sealed with a first sealing plate, wherein a second sealing plate is provided inside the sealing plate. The first block and the second block are joined by a lead plate that supplies current to a pair of lead wires derived from the end faces of the capacitor element, and the joined blocks are arranged between the respective sealing plates. An electrolytic capacitor, characterized in that the lead plate is cut off by the movement of the two blocks due to the swelling of the second sealing plate due to an increase in internal pressure at the time of abnormality, and a current supply path to the lead wire is cut off.