JPH0766085A - Aluminum electrolytic capacitor - Google Patents

Abstract

PURPOSE:To provide an aluminum electrolytic capacitor which prevents electrolyte from being volatilized and scattered by disposing a resin plate at a rear side of a sealer and does not impair hermetical sealability even when the plate is provided. CONSTITUTION:An electrolytic capacitor comprises a resin plate 31 of fluorine resin separate from an elastic sealer 2 disposed between the sealer 2 and a capacitor element 3. Through holes 21a, 21b of slightly smaller inner diameter than outer diameters of aluminum parts 4a, 5a of leads 4, 5 and tubes 31a, 31b are formed at the plate 31. The parts 4a, 5a are forced into the holes 21a, 21b and the tubes 31a, 31b, and outer peripheries of the parts 4a, 4b are brought into pressure contact with inner peripheries of the holes 21a, 21b and the tubes 31a, 31b.

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, and more particularly to a structure on the sealing portion side thereof.

[0002]

2. Description of the Related Art As shown in FIG. 6, an aluminum electrolytic capacitor (hereinafter referred to as an electrolytic capacitor) has a capacitor element 60 impregnated with an electrolytic solution inside an aluminum case 61. Since it is housed, the open end side of the aluminum case 61 is sealed with a rubber packing 62 (elastic sealing body) so that the electrolytic solution does not evaporate. Here, when the use of butyl rubber for the rubber packing 62 cannot sufficiently prevent the volatilization of the electrolytic solution, a fluororesin plate 65 is attached to the rubber packing 62 to suppress the permeation of the electrolytic solution into the rubber packing 62. A method can be considered.

However, in the electrolytic capacitor using the rubber packing 62 attached to the fluororesin plate, if the airtightness is to be ensured only by the pressing force of the lateral drawing portion 61a as in the conventional case, the hardness of the fluororesin plate is high, and therefore the rubber packing is performed. On the contrary, when 62 is thin, airtightness may be impaired. That is, if a resin plate having a high hardness is provided on the lower end surface of the rubber packing 62, the pressing force of the lateral narrowing portion 61 a is not evenly applied to the rubber packing 62 and unnatural stress is applied to the rubber packing 62. A gap is generated between the inner peripheral surfaces of the lead holes 62a, 62 and the outer peripheral surfaces of the lead wires 63, 64, and the lead lead holes 62a, 62b are formed.
This is because the airtightness is poor.

In view of the above problems, the object of the present invention is to
Another object of the present invention is to provide an aluminum electrolytic capacitor in which a resin plate is arranged on the back surface side of the sealing body to prevent volatilization of the electrolytic solution and the airtightness is not impaired even if the resin plate is provided.

[0005]

In order to solve the above problems, the present invention provides an elastic sealing body in which a lead wire of a capacitor element impregnated with γ-butyrolactone electrolyte or the like is inserted into a lead extraction hole. In an electrolytic capacitor (aluminum electrolytic capacitor) fixed at the open end side of the capacitor case by a laterally drawn part and an upper drawn part with respect to the capacitor case, between the capacitor element and the elastic sealing body, both end faces are highly resistant to chemicals. A resin plate made of resin is provided.

That is, the present invention is characterized in that a resin plate which is a separate body from the elastic sealing member is arranged so as to cover the end face of the elastic sealing member. Therefore, the permeation of the electrolytic solution through the elastic sealing body is suppressed by the resin plate. Here, since the resin plate is a separate body from the elastic sealing body, even if there is a resin plate on the back side of the elastic sealing body, the pressing force applied from the lateral narrowing part is uniformly applied to the elastic sealing body, and The inner peripheral surface of the extraction hole and the outer peripheral surface of the lead wire are in complete contact. In the present invention, the resin plate has a thickness of 1 to 200 μ, in addition to a relatively thick plate.
It also includes a thin sheet of about m.

Further, in the present invention, the resin plate has a through hole having an inner diameter smaller than the outer diameter of the lead wire at a position communicating with the lead drawing hole, for example, about 0. A through hole having an outer diameter dimension of 60 times to about 0.95 times is formed, and a lead wire is press-fitted into the through hole to press the outer peripheral surface of the lead wire and the inner peripheral surface of the through hole. However, it is preferable to ensure airtightness there as well. In this case, the inner peripheral edge of the through hole is in a state of being slightly drawn into the lead drawing hole by the lead wire.

According to another aspect of the present invention, an elastic sealing body in which a lead wire of a capacitor element impregnated with an electrolytic solution is inserted into a lead lead-out hole is provided with an elastic sealing member on the open end side of the capacitor case and the upper side of the capacitor case. In the electrolytic capacitor fixed by the squeezing section, a through hole with an inner diameter smaller than the outer diameter of the lead wire is formed on the end surface of the elastic sealing body on the capacitor element side at the position communicating with the lead drawing hole. A resin plate made of high resin is attached, and lead wires are press-fitted into the through holes.

That is, since the resin plate is attached to the end surface of the elastic sealing body on the capacitor element side, the resin plate suppresses the permeation of the electrolytic solution into the elastic sealing body. here,
Since the elastic sealing body and the resin plate are integrated, there is a concern that the pressing force applied from the lateral narrowing part may not be applied uniformly to the elastic sealing body, but the lead wire is pressed into the through hole of the resin plate. Since the outer peripheral surface of the lead wire and the inner peripheral surface of the through hole are in pressure contact with each other, airtightness can be ensured there as well. That is, since the outer peripheral surface of the lead wire is in close contact with both the inner peripheral surface of the lead drawing hole and the inner peripheral surface of the through hole, sufficient airtightness can be secured in the lead drawing hole even when the elastic sealing body is thin.

In the present invention, the resin plate is provided with a tube portion extending from the peripheral edge of the through hole into the lead drawing hole, the inner diameter of the tube portion is made smaller than the outer diameter of the lead wire, and the inside of the tube portion is provided. Again, it is preferable to press fit the lead wire.

Further, there may be adopted a construction in which a side surface portion which covers the side surface of the capacitor element is provided on the resin plate.

In the present invention, the resin having high chemical resistance means, for example, polyvinyl alcohol, copolymer of polyvinyl alcohol, polyamide, silicon resin, fluororesin or polypyrrole, which are solvents and solutes used in the electrolytic solution of the electrolytic capacitor. On the other hand, it means an insulating resin having high chemical stability.

[0013]

Embodiments of the present invention will now be described with reference to the accompanying drawings.

[Embodiment 1] FIG. 1A is a vertical sectional view of an electrolytic capacitor according to Embodiment 1, and FIG. 1B is a perspective view of an elastic sealing member and a resin plate used therein.

The electrolytic capacitor 10 of this example has a rating of 10
An aluminum electrolytic capacitor having a wv of 1000 μF and a length of 15 mm, the capacitor element 3 being impregnated with an electrolytic solution in which γ-butyrolactone (main solvent) is dissolved such as tetramethylammonium hydrogen phthalate, and two leads. It has an elastic sealing body 2 (butyl rubber packing) having a thickness of 3 mm, in which lead lead-out holes 2a and 2b through which the wires 4 and 5 pass are formed, and an aluminum case 6 sealed with the elastic sealing body 2. The elastic sealing body 2 is fixed on the open end side of the aluminum case 6 by the lateral narrowing portion 6a and the upper narrowing portion 6b of the aluminum case 6 to seal the capacitor element 3 inside the aluminum case 6. The lead wires 4 and 5 include aluminum parts 4a and 5a called round bars on the capacitor element 3 side.
It has CP lines 4b and 5b on the tip side thereof.

The electrolytic capacitor 10 of this embodiment is made of a fluororesin (made of 4-fluoroethylene resin) having a high chemical resistance between the lower end surface 2c of the elastic sealing body 2 and the upper end surface 3a of the capacitor element 3. It has a disc-shaped resin plate 11 having a thickness of about 10 μm. The resin plate 11 is formed with through holes 11a and 11b having an inner diameter slightly larger than the outer diameters of the lead wires 4 and 5 at positions communicating with the lead lead-out holes 2a and 2b of the elastic sealing body 2. Through holes 11a, 11b of the lead wires 4, 5
Is in a penetrating state. Here, the elastic sealing body 2 and the resin plate 11 are separate members, and in the manufacturing process of the electrolytic capacitor 10, the lead protruding from the capacitor element 3 before the elastic sealing body 2 is attached to the capacitor element 3. The resin plate 11 is attached to the capacitor element 3 by passing the wires 4 and 5 through the through holes 11 a and 11 b.

In the electrolytic capacitor 10 thus constructed, the resin plate 11 is in close contact with the lower end surface 2c of the elastic sealing body 2, and the lower end surface 2c of the elastic sealing body 2 is covered with the resin plate 11. The permeation of the electrolytic solution into the elastic sealing body 2 is suppressed. Here, the speed at which the electrolytic solution permeates through the elastic sealing body 2 is the same as the speed at which the electrolytic solution permeates into the elastic sealing body 2.
The rate at which the electrolytic solution diffuses through the elastic sealing body 2 is defined. Among them, in the electrolytic capacitor 10 of this example, the rate at which the electrolytic solution permeates into the elastic sealing body 2 is extremely low. Therefore,
Since the electrolytic solution permeates through the elastic sealing body 2 at a low speed, dry-up of the capacitor element 3 is suppressed, so that the electrolytic capacitor 10 can have a long life. In addition, the resin plate 11
Is also in close contact with the upper end surface 3a of the capacitor element 3, and the evaporation area of the electrolytic solution is small on the capacitor element 3 side. For this reason, since the evaporation rate of the electrolytic solution from the capacitor element 3 is low, it is possible to further suppress the dry-up of the capacitor element 3.

Further, in the electrolytic capacitor 10 of this example, since the elastic sealing body 2 and the resin plate 11 are separate bodies, the resin plate 1
No. 1 does not prevent airtightness by the lateral narrowing portion 6a. That is,
When the composite sealing body in which the resin plate 11 and the elastic sealing body 2 are laminated is used, the hardness of the resin plate 11 is high. Therefore, when the elastic sealing body 2 is thinned, the pressing force by the lateral narrowing portion 6a causes the elastic sealing body to be thin. 2 is not evenly applied to the lower end surface 2c of the lead wire 2 and a gap may be generated between the inner peripheral surfaces of the lead drawing holes 2a and 2b and the outer peripheral surfaces of the aluminum portions 4a and 5a. Since the elastic sealing body 2 and the resin plate 11 are separate bodies, the pressing force by the lateral narrowing portion 6a is evenly applied to the lower end surface 2c side of the elastic sealing body 2, so that the lead drawing hole 2
The inner peripheral surfaces of a and 2b and the outer peripheral surfaces of the aluminum portions 4a and 5a are in complete contact with each other, and the presence of the resin plate 11 does not prevent airtightness in the lead extraction holes 2a and 2b.

[Embodiment 2] FIG. 2A is a vertical sectional view of an electrolytic capacitor according to Embodiment 2, and FIG. 2B is a perspective view of an elastic sealing member and a resin plate used therein. here,
Since the electrolytic capacitor of the present example and the electrolytic capacitors of the examples described below have the same basic configuration as the electrolytic capacitor according to the example 1, common parts are denoted by the same reference numerals, Detailed description thereof will be omitted.

The electrolytic capacitor 20 of this embodiment also has a thickness of about 100 μm made of fluororesin having high chemical resistance between the lower end surface 2c of the elastic sealing body 2 and the upper end surface 3a of the capacitor element 3.
m resin plate 21, and this resin plate 21 is also a separate body from the elastic sealing body 2.

The resin plate 21 has through holes 21a, 21 at positions communicating with the lead drawing holes 2a, 2b of the elastic sealing body 2.
b is formed. Here, the through holes 21a and 21b are
Before passing the lead wires 4 and 5, that is, the electrolytic capacitor 1
Before assembling 0, the inner diameter is slightly smaller than the outer diameters of the aluminum portions 4a, 5a of the lead wires 4, 5. Therefore, in this example, in the assembling process of the electrolytic capacitor 10, the aluminum portions 4a, 5a are press-fitted into the through holes 21a, 21b, so that the aluminum portions 4a, 5a are not pressed.
The outer peripheral surface of a is pressed against the inner peripheral surfaces of the through holes 21a and 21b.

Further, the resin plate 21 has a cylindrical side surface portion 21c extending downward from the outer peripheral edge thereof and covering the side surface 3b of the capacitor element 3.

In the electrolytic capacitor 20 thus constructed, since the elastic sealing body 2 and the resin plate 21 are separate members, the pressing force from the lateral narrowing portion 6a is present regardless of the presence of the resin plate 21. Is uniformly applied to the elastic sealing body 2, and the inner peripheral surfaces of the lead lead-out holes 2a and 2b are in close contact with the outer peripheral surfaces of the aluminum portions 4a and 5a. Therefore, while ensuring airtightness in the lead extraction holes 2a, 2b,
The resin plate 21 covers the lower end surface 2c of the elastic sealing body 2 and the upper end surface 3a of the capacitor element 3 to prevent the capacitor element 3 from drying up.

Further, the through holes 21a and 21b having an inner diameter slightly smaller than the outer diameters of the aluminum portions 4a and 5a are formed in the resin plate 2.
The aluminum parts 4a and 5a are press-fitted into the through holes 21a and 21b. Therefore, the outer peripheral surfaces of the aluminum portions 4a, 5a are pressed against the inner peripheral surfaces of the through holes 21a, 21b to prevent the electrolytic solution from creeping up inside the lead lead-out holes 2a, 2b. Therefore, the inner peripheral surfaces of the lead lead-out holes 2a, 2b are unlikely to swell with the electrolytic solution. Further, even if a potential is applied to the lead wires 4 and 5, quaternary ammonium ions in the electrolytic solution are not attracted to the inside of the lead extraction holes 2a and 2b. The inner peripheral surface of 2b does not deteriorate. Therefore, the airtightness in the lead lead-out holes 2a, 2b can be ensured for a long period of time, and problems such as liquid leakage do not occur.

Further, in the electrolytic capacitor 20 of this example,
Since the side surface portion 21c of the resin plate 21 covers the side surface portion 3b of the capacitor element 2 and also suppresses the evaporation of the electrolytic solution from the side surface portion 3b of the capacitor element 3, the capacitor element 3 is more reliably prevented from being dried up. it can.

[Embodiment 3] FIG. 3A is a vertical sectional view of an electrolytic capacitor according to Embodiment 3, and FIG. 3B is a perspective view of an elastic sealing body and a resin plate used therein. The electrolytic capacitor of this example corresponds to an improved example of the electrolytic capacitor according to the second embodiment.

That is, the electrolytic capacitor 30 of this example also
Between the lower end surface 2c of the elastic sealing body 2 and the upper end surface 3a of the capacitor element 3, there is a resin plate 31 made of a fluororesin having a high chemical resistance and having a thickness of about 100 μm. It is a separate body from the sealing body 2. The insulating plate 31 is provided with through holes 21a and 21b having inner diameters slightly smaller than the outer diameters of the aluminum portions 4a and 5a of the lead wires 4 and 5 at positions communicating with the lead drawing holes 2a and 2b of the elastic sealing body 2. Further, tube portions 31a and 31b are formed on the back surface side of the insulating plate 31 and extend from the peripheral edges of the through holes 21a and 21b.
Here, the inner diameters of the pipe portions 31a and 31b are also equal to the through holes 21a and 2
As with 1b, the aluminum portions 4a of the lead wires 4 and 5,
It is slightly smaller than the outer diameter of 5a.

Here, since the resin plate 31 is made of fluororesin and has a lower flexibility than the elastic sealing body 2, only the pressing force from the lateral narrowing portions 6a and 6b causes the pipe portion 31a, Three
Although the outer peripheral surface of 1b and the inner peripheral surfaces of the lead lead-out holes 2a, 2b can be brought into close contact with each other, the inner peripheral surfaces of the pipe portions 31a, 31b and the outer peripheral portions of the aluminum portions 4a, 5a of the lead wires 4, 5 are formed. The surface cannot be completely attached.

Therefore, in this example, the inner diameters of the through holes 21a and 21b and the tube portions 31a and 31b are set to the aluminum portion 4a,
It is set to be smaller than the outer diameter of 5a, and these through holes 21a,
21b and the pipe parts 31a, 31b are press-fitted into the aluminum parts 4a, 5a, so that the outer peripheral surfaces of the aluminum parts 4a, 5a are penetrated into the through holes 21a, 21b and the pipe part 3.
It is pressed against the inner peripheral surfaces of 1a and 31b.

Therefore, in the electrolytic capacitor 30 of this embodiment, even if the small flexible tube portions 31a and 31b are arranged inside the lead lead-out holes 2a and 2b, the airtightness there is completely maintained. Therefore, since the lower end surface 2c of the elastic sealing body 2 is covered with the resin plate 31, the permeation of the electrolytic solution from the elastic sealing body 2 is suppressed, which is similar to the electrolytic capacitors according to the first and second embodiments. In addition to producing the effect, the airtightness inside the lead extraction holes 2a, 2b is also high.

Further, since the electrolytic solution does not crawl between the outer peripheral surfaces of the tube portions 31a and 31b and the inner peripheral surfaces of the lead drawing holes 2a and 2b, the inner peripheral surfaces of the lead drawing holes 2a and 2b are Does not swell with electrolyte. In addition, the lead wire 4,
Even if an electric potential is applied to 5, the ions in the electrolytic solution cannot be attracted to the inner surface of the lead extraction holes 2a and 2b.
The inner peripheral surfaces of the lead lead-out holes 2a, 2b are not deteriorated even by the ions in the electrolytic solution. Therefore, it is possible to prevent the capacitor element 3 from being dried up, and the lead lead-out hole 2
Liquid leakage from a and 2b can be prevented.

[Embodiment 4] FIG. 4A is a vertical sectional view of an electrolytic capacitor according to Embodiment 4, and FIG. 4B is a perspective view of an elastic sealing body used therein.

The electrolytic capacitor 40 of this example also has a disc-shaped thickness of polyvinyl alcohol having a high chemical resistance between the lower end surface 2c of the elastic sealing body 2 and the upper end surface 3a of the capacitor element 3. It has a resin plate 41 (resin layer) of 100 μm.

Here, the resin plate 41 is attached to the lower end surface 2c of the elastic sealing body 2, and the resin plate 41 and the elastic sealing body 2 together form a composite sealing body 40a. ing. The resin plate 41 has through holes 41a and 41b having an inner diameter smaller than the outer diameters of the lead wires 4 and 5 at positions communicating with the lead lead-out holes 2a and 2b of the elastic sealing body 2. Through holes 4 having an inner diameter of about 0.60 times to about 0.95 times the outer diameter of the aluminum portions 4a, 5b of 4, 5
1a and 41b are formed. Therefore, in this example,
The through holes 41 are formed in the aluminum portions 4a and 5a of the lead wires 4 and 5.
The aluminum portions 4a and 5a are inserted into the through holes 41a and 41b by press-fitting into the a and 41b,
The outer peripheral surfaces of the aluminum portions 4a and 5a have through holes 41a and 4a.
It is in a state of being pressed against the inner peripheral surface of 1b. Therefore, the resin plate 4
The inner peripheral edges of the through holes 41a and 41b of the lead wire 1 and the aluminum portion 4a and 5a of the lead wires 4 and 5 lead the lead lead hole 2
It is in a state of being slightly drawn into the insides of a and 2b.

In the thus constructed electrolytic capacitor 40, since the lower end surface 2c of the elastic sealing body 2 does not come into contact with the electrolytic solution, permeation of the electrolytic solution into the elastic sealing body 2 is suppressed, and the electrolytic solution is removed from the elastic sealing body 2. The rate of penetration is significantly lower.
Moreover, the gas permeability coefficient of polyvinyl alcohol is, for example, 0.00052 × when expressed by the gas permeability coefficient of oxygen.
It is 10 ^-10 [cm ^-3 (STP) cm ^-1 s ^-1 cmHg ^-1 ], which is extremely small. Therefore, the dry-up of the capacitor element 3 is prevented, and the life of the electrolytic capacitor 40 can be extended.

Here, since the resin plate 41 having a high hardness is attached to the lower end surface 2c of the elastic sealing body 2, the pressing force is uniform with respect to the elastic sealing body 2 only by the pressing force from the lateral narrowing portion 6a. It is feared that the airtightness in the lead lead-out holes 2a, 2b cannot be ensured completely, but in this example, the aluminum portions 4a, 5a are press-fitted into the through holes 41a, 41b. The outer peripheral surface of the is pressed against the inner peripheral surfaces of the through-holes 41a and 41b, where sufficient airtightness is ensured. Therefore, despite the fact that the resin plate 41 made of polyvinyl alcohol is attached to the elastic sealing body 2, the conventional electrolytic capacitor that tries to ensure airtightness only by the pressing force from the lateral narrowing portion 6a (shown in FIG. 6). Unlike the electrolytic capacitor), even if the elastic sealing body 2 is thin, the airtightness with respect to the lead lead-out holes 2a and 2b is perfect, and liquid leakage does not occur from there.

Moreover, since the resin plate 41 is integrated with the elastic sealing body 2 to form the composite sealing body 40a, the number of parts does not increase, so that the highly reliable electrolytic capacitor 40 can be manufactured at low cost. .

[Embodiment 5] FIG. 5A is a vertical sectional view of an electrolytic capacitor according to Embodiment 5, and FIG. 5B is a perspective view of an elastic sealing body used therein. The electrolytic capacitor of this example corresponds to an improved example of the electrolytic capacitor according to the fourth embodiment.

That is, the electrolytic capacitor 50 of this example also
Between the lower end surface 2c of the elastic sealing body 2 and the upper end surface 3a of the capacitor element 3, there is a resin plate 51 made of fluororesin (4-fluoroethylene resin) having a thickness of about 10 μm. 51 is bonded to the lower end surface 2c of the elastic sealing body 2 to form a composite sealing body 50a that is integral with the elastic sealing body 2.

The resin plate 51 also has a through hole 41a having an inner diameter smaller than the outer diameters of the aluminum portions 4a and 5a of the lead wires 4 and 5 at positions communicating with the lead lead-out holes 2a and 2b of the elastic sealing body 2. , 41b are formed and the insulating plate 5 is formed.
Pipe portions 51a and 51b extending from the peripheral edges of the through holes 41a and 41b are formed on the back surface side of the pipe 1.
Are inside the lead lead-out holes 2a and 2b. The inner diameters of the pipe portions 51a and 51b are set smaller than the outer diameters of the aluminum portions 4a and 5a, like the inner diameters of the through holes 41a and 41b. In this example, the through holes 41a and 41b and the pipe portions are formed. The inner diameters of the portions 51a and 51b are set to be approximately 0.60 to 0.95 times the outer diameters of the aluminum portions 4a and 5b of the lead wires 4 and 5.

Here, when the resin plate 51 and the elastic sealing body 2 are bonded to each other to manufacture the composite sealing body 50a,
The end surface 51c of the resin plate 51 and the lower end surface 2c of the elastic sealing body 2
And the outer peripheral surfaces of the tube portions 51a and 51b may be adhered to the inner peripheral surfaces of the lead drawing holes 2a and 2b.
In this example, the manufacturing process of the composite sealing body 50a is simplified,
For the purpose of reducing the production cost, the end surface 5 of the resin plate 51
Only 1c is bonded to the lower end surface 2c of the elastic sealing body 2, and the outer peripheral surfaces of the elastic tube portions 51a and 51b have lead lead-out holes 2a,
It is not adhered to the inner peripheral surface of 2b.

In the thus constructed electrolytic capacitor 50, since the resin plate 51 is made of fluororesin, its flexibility is lower than that of the elastic sealing body 2, and only the pressing force from the horizontal throttle portions 6a and 6b is applied. Then, with the outer peripheral surfaces of the pipe portions 51a and 51b,
Even if the inner peripheral surfaces of the lead lead-out holes 2a, 2b can be brought into close contact with each other, the inner peripheral surfaces of the tube portions 51a, 51b and the outer peripheral surfaces of the aluminum portions 4a, 5a of the lead wires 4, 5 are completely brought into close contact with each other. I can't let you do it.

Therefore, in this example, the inner diameters of the through holes 41a and 41b and the tube portions 51a and 51b are set to the aluminum portion 4a and
It is set to be smaller than the outer diameter of 5a, and these through holes 41a,
By press-fitting the aluminum parts 4a and 5a into the inside of the 41b and the pipe parts 51a and 51b, the outer peripheral surfaces of the aluminum parts 4a and 5a are passed through the through holes 41a and 41b and the pipe part 5.
It is pressed against the inner peripheral surfaces of 1a and 51b.

Therefore, in the electrolytic capacitor 50 of this embodiment, even if the small flexible tube portions 51a and 51b are arranged in the lead lead-out holes 2a and 2b, the lead lead-out holes 2a and 2b are formed.
Airtightness against b is completely retained. Therefore, since the lower end surface 2c of the elastic sealing body 2 is covered with the resin plate 51,
In addition to the effect similar to that of the electrolytic capacitor according to the fourth embodiment such as the suppression of the permeation of the electrolytic solution from the elastic sealing body 2, the airtightness inside the lead extraction holes 2a and 2b is also high. Moreover, since the inner peripheral surfaces of the lead lead-out holes 2a, 2b do not come into contact with the electrolytic solution, they do not deteriorate,
No problems such as liquid leakage will occur.

[Other Examples] In the above Examples 1 to 5, the resin plate made of polyvinyl alcohol or fluororesin was used. However, in addition to this, silicone resin, polyvinyl acetate-polyvinyl alcohol are also used. Resins such as copolymers, polyamides, and polypyrroles can be used. In particular, when a resin having low gas permeability is selected, for example, polyvinyl alcohol, a copolymer thereof, polyamide, polypyrrole, etc., having a gas permeability coefficient of oxygen of 1.0 × 10 ⁻¹⁰ [cm ^{− 3} (ST
P) cm ^-1 s ^-1 cmHg ^-1 ] The following shall be adopted. Further, when a resin having high chemical stability is selected, a fluororesin is adopted. In this case, it is not limited to 4-fluoroethylene resin, 4-fluoroethylene-6-fluoropropylene copolymer, 4-fluoroethylene-perfluoroalkoxyethylene copolymer, 4-fluoroethylene- Ethylene copolymer, vinylidene fluoride and the like can also be used.

The thickness of the resin plate is about 1 to 200 μm.
Of these, those having a thickness of about 10 to 100 μm are preferable in terms of airtightness and handleability.

[0047]

As described above, the electrolytic capacitor according to the present invention is characterized in that a separate resin plate covering the end face of the elastic sealing body is arranged between the capacitor element and the elastic sealing body. Therefore, according to the present invention, permeation of the electrolytic solution from the elastic sealing body can be suppressed by the resin plate, so that the life of the electrolytic capacitor can be extended. Even in this case, since the resin plate is separate from the elastic sealing body, the pressing force applied from the lateral narrowing part is evenly applied to the elastic sealing body, and the inner peripheral surface of the lead lead-out hole and the outer periphery of the lead wire. Since the surface is in close contact with the surface, airtightness of the lead extraction hole can be ensured.

In another embodiment of the present invention, a resin plate having a through hole having an inner diameter smaller than the outer diameter of the lead wire is attached to the end surface of the elastic sealing body on the capacitor element side, The feature is that the lead wire is press-fitted into the through hole. Therefore, the permeation of the electrolytic solution from the elastic sealing body can be suppressed by the resin plate, so that the life of the electrolytic capacitor can be extended. In this case, since the resin plate is attached to the elastic sealing body, it is feared that the pressing force applied from the lateral narrowing portion is difficult to be uniformly applied to the elastic sealing body. Since the lead wire is press-fitted into the small through hole, the outer peripheral surface of the lead wire is pressed against the inner peripheral surface of the through hole, and airtightness can be secured there.

[Brief description of drawings]

1A is a vertical cross-sectional view showing the configuration of an electrolytic capacitor according to a first embodiment of the present invention, and FIG. 1B is a perspective view showing the configurations of an elastic sealing body and a resin plate thereof.

2A is a vertical cross-sectional view showing the configuration of an electrolytic capacitor according to a second embodiment of the present invention, and FIG. 2B is a perspective view showing the configurations of an elastic sealing body and a resin plate thereof.

3A is a vertical cross-sectional view showing the configuration of an electrolytic capacitor according to a third embodiment of the present invention, and FIG. 3B is a perspective view showing the configurations of an elastic sealing body and a resin plate thereof.

FIG. 4 (a) is a vertical cross-sectional view showing the configuration of an electrolytic capacitor according to a fourth embodiment of the present invention, and FIG. 4 (b) is a cross-sectional view showing the configuration of a composite sealing body including an elastic sealing body and a resin plate. Is.

5A is a vertical cross-sectional view showing the configuration of an electrolytic capacitor according to a fifth embodiment of the present invention, and FIG. 5B is a cross-sectional view showing the configuration of a composite sealing body including an elastic sealing body and a resin plate. Is.

FIG. 6 is a vertical sectional view showing the structure of a conventional electrolytic capacitor.

[Explanation of symbols]

10, 20, 30, 40, 50 ... Electrolytic capacitor 2 ... Elastic sealing body 3 ... Capacitor element 4, 5 ... Lead wire 4a, 5a ... Aluminum part 4b, 5b ... CP Line 6 ... Aluminum case 6a ... Horizontal drawing part 6b ... Upper drawing part 11, 21, 31, 41, 51 ... Resin plate 11a, 11b, 21a, 21b, 41a, 41b ...
-Penetration hole 21c ... Side surface part 31a, 31b, 51a, 51b ... Pipe part 40a, 50a ... Composite sealing body

 ─────────────────────────────────────────────────── (72) Inventor Tsutomu Miyashita Ina City, Ina City, Nagano Prefecture, 165 Ina, Rubicon Co., Ltd. (72) Inventor Akihiko Komatsu Ina City, Ina City, Nagano Prefecture, 165, Ina Factory, Rubicon Co., Ltd.

Claims (9)

[Claims] 1. An aluminum electrolytic capacitor in which an elastic sealing body, in which a lead wire of a capacitor element impregnated with an electrolytic solution is inserted into a lead extraction hole, is fixed at the open end side of the capacitor case by a lateral throttle portion and an upper throttle portion with respect to the capacitor case. 2. The aluminum electrolytic capacitor according to claim 1, further comprising a resin plate made of a resin having high chemical resistance, the resin plate being in contact with both end faces between the capacitor element and the elastic sealing body. 2. The resin plate according to claim 1, wherein a through hole having an inner diameter smaller than an outer diameter of the lead wire is formed at a position communicating with the lead drawing hole, The aluminum electrolytic capacitor, wherein the lead wire is press-fitted. 3. An aluminum electrolytic capacitor in which an elastic sealing body in which a lead wire of a capacitor element impregnated with an electrolytic solution is inserted into a lead lead-out hole is fixed at the open end side of the capacitor case by a lateral throttle part and an upper throttle part with respect to the capacitor case. In the above-mentioned resin having a high chemical resistance, a through hole having an inner diameter smaller than the outer diameter of the lead wire is formed at the end surface of the elastic sealing body on the capacitor element side at a position communicating with the lead drawing hole. An aluminum electrolytic capacitor, wherein a resin plate made of is attached, and the lead wire is pressed into the through hole. 4. The inner diameter of the through hole according to claim 2 or 3, wherein the inner diameter of the through hole is about 0.60 times the outer diameter of the lead wire.
Aluminum electrolytic capacitor characterized by being in the range up to 95 times. 5. The resin plate according to any one of claims 2 to 4, wherein the resin plate has a tube portion extending from the peripheral edge of the through hole into the lead drawing hole, and the tube portion has an inner diameter of the lead wire. Is smaller than the outer diameter of the aluminum electrolytic capacitor, and the lead wire is press-fitted inside the aluminum electrolytic capacitor. 6. The aluminum electrolytic capacitor according to claim 1, wherein the resin plate has a side surface portion that covers a side surface of the capacitor element. 7. The resin plate according to claim 1, wherein the resin plate has a permeability coefficient of oxygen gas of 1.0 × 10.
^-10 [cm ^-3 (STP) cm ^-1 s ^-1 cmHg ^-1 ] An aluminum electrolytic capacitor characterized by comprising the following resin. 8. The resin plate according to claim 7, wherein the resin plate is polyvinyl alcohol, a polyvinyl alcohol copolymer,
An aluminum electrolytic capacitor comprising a resin of any one of polyamide and polypyrrole. 9. The aluminum electrolytic capacitor according to claim 1, wherein the resin plate is made of fluororesin.