JPH11186114A - Electrolytic capacitor and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrolytic capacitor having a stable and high properties of long life, also capable of offering an excellency for high productivity and reduction of manufacturing cost by improving a sealing structure. SOLUTION: A capacitor element 2 wound with a separator for each positive and negative electrode foil connected with a lead terminal 1 is stored in an armor case 3 made of aluminum, etc., shaped with a tubular having its bottom. An encapsulant 10 to seal an opening of the armor case 3 is constructed by a signal member, and a through hole 11 for pulling out a lead terminal is formed at a pre-determined position. A column part 12 projecting inside is formed on an inner face of pulling out side of the lead terminal of the through hole 11. A tube having a high elastic modulus is mounted in the through hole in advance, and a round bar part 1b of the lead terminal 1 is inserted in the tube.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrolytic capacitor, and more particularly, to an electrolytic capacitor having an improved sealing structure.

[0002]

2. Description of the Related Art An electrolytic capacitor is formed by winding a bipolar electrode foil connected to a lead terminal as an electrode lead-out means through a separator to form a capacitor element. It is configured to be sealed in a cylindrical outer case. Conventionally, in such an electrolytic capacitor, the lead terminal is composed of a flat plate portion connected to the electrode foil, a round bar portion for penetrating the sealing body, and an external connection portion. On the other hand, as a sealing body for sealing the opening of the outer case, rubber having a low elastic modulus has been used from the viewpoint of maintaining the airtightness between the lead terminal penetrating the sealing body and the outer case.

However, since rubber has a large gas permeability coefficient, when rubber is used for the sealing member, the electrolytic solution permeates through the rubber and scatters to the outside, or gas (moisture, oxygen, etc.) from the outside. Have penetrated into the case, which has led to a reduction in the life characteristics of the capacitor. In order to prevent such a situation, it is conceivable to use a metal material or a hard resin having a small gas permeability coefficient for the sealing body, but generally, a material having a small gas permeability coefficient has a high elastic coefficient and is compared with rubber. Since the hardness is high, it is difficult to maintain airtightness at a contact portion between the lead terminal and the outer case penetrating the sealing body.

In order to reduce the gas permeability and improve the airtightness at the contact portion with the lead terminal, FIG.
As shown in the above, on the inner surface of a through-hole formed in a sealing plate made of a hard resin or the like, a tubular elastic body made of a rubber or a fluororesin or the like is bonded or embedded to form a sealing body,
Techniques have been developed in which lead terminals are drawn from the elastic body. Such a technique is disclosed in, for example, Japanese Utility Model Laid-Open No. 55-7317 and Japanese Utility Model Laid-Open No. 55-115041.
And Japanese Unexamined Utility Model Publication No. 55-132936.

[0005]

However, as described above, when the sealing plate and the elastic body are bonded to each other, or when the elastic body is embedded in the sealing plate and integrally formed, the elastic body is formed. Although the shape stability is increased, the elastic body is relatively hard to deform. That is, as shown in FIG. 9, since the conventional elastic body is integrated with the sealing plate having high hardness, when the lead terminal is inserted through the elastic body, the elastic body is pressed by the round bar portion of the lead terminal. Even if it is done, the deformation in the length direction of the elastic body is prevented by the sealing plate, and the elastic body cannot extend in the length direction. As a result, there is a disadvantage that the elastic body is compressed and its volume is reduced, a high stress is generated, and the insertion pressure of the lead terminal is increased. Further, since the elastic body cannot be made of a material having a high elastic modulus and the gas permeability coefficient becomes large, the gas permeability cannot be reduced.

On the other hand, if the inner diameter of the elastic body is configured to be substantially equal to the outer diameter of the round bar portion of the lead terminal in order to reduce the pressing force at the time of inserting the lead terminal, the elastic body can be processed in accordance with the processing accuracy and dimensional accuracy. A slight error in the size of the elastic body causes a problem that the airtightness between the elastic body and the lead terminal is reduced, and the variation in the life characteristics is increased.

On the other hand, by changing the manufacturing method of the sealing body, it is possible to ensure higher processing accuracy and dimensional accuracy than before, but such a method only causes a decrease in production efficiency. In addition, the production cost is high, which is not desirable. Further, the conventional method involves bonding or embedding an elastic body to the inner surface of the through-hole at the time of molding the sealing plate, and thus requires a complicated process and has a problem of lowering production efficiency. Was.

The present invention has been proposed to solve the above-mentioned problems of the prior art.
An object of the present invention is to provide an excellent electrolytic capacitor which has a stable and high life characteristic by improving a sealing structure and which can contribute to improvement of production efficiency and reduction of manufacturing cost. Also,
Another object of the present invention is to provide an excellent manufacturing method capable of efficiently manufacturing such an excellent electrolytic capacitor at low cost.

[0009]

In order to solve the above-mentioned problems, the invention according to claim 1 comprises a capacitor element formed by winding a bipolar electrode foil to which an electrode lead-out means is connected via a separator; Comprising a cylindrical outer case with a bottom and a sealing means attached to the opening of the outer case, wherein the electrode lead-out means is a flat plate for internal connection, and a round bar for penetrating the sealing means, And an external connection part, in the electrolytic capacitor in which the electrode lead-out means is drawn out of the outer case through the through-hole provided in the sealing means, the elastic modulus is provided in the through-hole provided in the sealing means. A tube made of a high material is mounted, and a round bar portion of the electrode lead-out means is inserted into the tube.

According to this structure, a tube made of a material having a high elastic modulus is attached to the inner surface of the through hole provided in the closing means, and the electrode drawing means is inserted into the tube. Since the portion is joined to the tube, the airtightness between the sealing means and the electrode lead means can be improved by the tube. In particular, when inserting the round bar portion of the electrode lead-out means into the tube attached to the through-hole, since this tube is not bonded to the through-hole with an adhesive or the like, the tube is pressed by the electrode pull-out means. Since the tube extends in the insertion direction, the elasticity of the tube is utilized to facilitate the operation of inserting the electrode lead-out means into the tube. Further, by extending in the insertion direction, the stress is diffused, and the adhesion between the tube and the round bar portion is improved.

According to a second aspect of the present invention, there is provided a capacitor element formed by winding a bipolar electrode foil to which electrode extraction means is connected via a separator, a bottomed cylindrical outer case for housing the capacitor element, and an outer case. A sealing means attached to the opening of the case, wherein the electrode lead means comprises a flat plate part for internal connection, a round bar part for sealing means penetration, and an external connection part, and the electrode lead means is In the electrolytic capacitor drawn out of the outer case through the through hole provided in the sealing means, an inner surface on the electrode lead side of the through hole provided in the sealing means is formed with a step portion projecting inward, A tube made of a material having a high elastic modulus is mounted in the through hole, and a round bar portion of the electrode lead-out means is inserted into the tube.

According to this structure, in addition to the functions and effects of the first aspect of the present invention, a stepped portion is formed on the inner surface of the through-hole on the electrode lead-out side so as to protrude inward. Even if the tube is pressed at the time of insertion, the tube is locked by the step portion, and therefore does not fall out of the through hole.

In the electrolytic capacitor according to the present invention, the relative dimensional relationship between the round bar portion of the electrode drawing means, the tube, and the through hole formed in the sealing means is specifically limited. It is. An electrolytic capacitor according to a third aspect is the electrolytic capacitor according to the first aspect, wherein the inner diameter of the tube is smaller than the outer diameter of the round bar portion of the electrode lead-out means. According to this configuration, the inner peripheral surface of the tube and the outer peripheral surface of the round bar portion of the electrode lead-out means can be securely brought into close contact with each other over the entire contact region, so that the airtightness of this portion is further improved. be able to.

According to a fourth aspect of the present invention, there is provided the electrolytic capacitor according to any one of the first to third aspects, wherein the tube is attached to the round bar portion of the electrode lead-out means. Is larger than the diameter of the through-hole. According to this configuration, when the round bar portion of the electrode lead-out means is inserted into the tube mounted in the through-hole, the outer peripheral surface of the tube and the inner peripheral surface of the through-hole are reliably formed over the entire contact area. The airtightness of this portion can be further improved.

According to a fifth aspect of the present invention, in the electrolytic capacitor according to any one of the first to fourth aspects, of the electrolytic capacitor according to any one of the first to fourth aspects, of the opening end of the through hole, the one on the insertion side of the electrode lead-out means. The diameter of the opening end is larger than the diameter of the center. According to this configuration, since the through hole formed in the closing means is expanded toward the opening end on the insertion side of the electrode drawing means, the tube can be easily inserted into the through hole, and at least the central portion of the through hole can be inserted. Thus, the outer peripheral surface of the tube and the inner peripheral surface of the through hole can be securely brought into close contact with each other, and the airtightness of this portion can be further improved.

According to a sixth aspect of the present invention, in the electrolytic capacitor according to any one of the first to fifth aspects, the sealing means includes a first sealing member made of a hard material and an outer periphery thereof. And a second sealing member made of a flexible material attached to the second member. According to this configuration, even when there is a slight variation in the dimensions of the first sealing member, the dimensional error can be absorbed by the elasticity of the second sealing member made of a flexible material disposed on the outer periphery thereof. The outer peripheral surface of the sealing means and the inner peripheral surface of the opening of the outer case can be securely brought into close contact with each other,
The airtightness of this part can be improved.

According to a seventh aspect of the present invention, in the electrolytic capacitor according to the sixth aspect, the second sealing member is formed in a tubular shape, and an inner diameter thereof is smaller than an outer diameter of the first sealing member. It is characterized by the following.
According to this configuration, in the sealing means, the inner peripheral surface of the second sealing member and the outer peripheral surface of the first sealing member can be securely brought into close contact with each other over the entire contact area. The airtightness can be improved.

In the electrolytic capacitors according to the eighth and ninth aspects, the materials used for the tubes and the sealing means are specifically limited. The electrolytic capacitor according to claim 8 is the electrolytic capacitor according to any one of claims 1 to 7, wherein the material having a high elastic modulus is rubber, a fluororesin, a shrinkable tube, polyethylene, polyester, or polyimide. , Polyamide, nylon, polyamideimide, silicone resin, silicone rubber, poly-4-methylpentene-1 (crystalline polyolefin), and ethylene vinyl alcohol. That is, in the electrolytic capacitors according to the first to seventh aspects, a material having a high elastic modulus can be appropriately selected. In particular, by using the material according to the eighth aspect, sufficient flexibility of the tube can be ensured. The quality can be improved, for example, the airtightness of the portion can be improved, and the workability and cost are also excellent.

According to a ninth aspect of the present invention, in the electrolytic capacitor according to any one of the first to eighth aspects, the sealing means is made of a fluororesin, polyphenylene sulfide, nylon, phenol, epoxy, polysulfone. A group of resin materials including polyimide, polyamide imide, polyoxybenzylene polyethylene, polypropylene, polycarbonate, a group of metal materials including aluminum, tantalum, magnesium, copper, nickel, titanium, or alloys thereof, hard rubber, ceramic, It is characterized by being composed of a material selected from glass. That is, in the electrolytic capacitors of claims 1 to 8, the type of material used for the sealing means can be appropriately selected.
By using the materials described, the gas permeability of the sealing means can be sufficiently reduced, and the quality can be improved, and also the workability and cost are excellent.

According to a tenth aspect of the present invention, in the electrolytic capacitor according to any one of the first to ninth aspects, the tip of the outer case opening abuts on the sealing means by drawing. It is characterized by having. That is, in the electrolytic capacitors according to claims 1 to 9, the specific shape of the outer case opening can be appropriately selected. In particular, as described in claim 10, the tip of the outer case opening corresponds to the sealing means. By contacting,
The pressing of the sealing means is strengthened, so that the sealing means can be prevented from jumping out of the outer case due to thermal stress.

According to a eleventh aspect of the present invention, there is provided a method of manufacturing an electrolytic capacitor, comprising: forming a capacitor element by winding a bipolar electrode foil connected to an electrode lead means through a separator; The method includes an assembling step of sealing the inside of the cylindrical outer case. Further, as the electrode lead means, an electrode lead means comprising a flat plate part for internal connection, a round bar part for penetrating the sealing means, and an external connection part is used. And in such a manufacturing method, a step forming step of forming an inwardly projecting step on the inner surface of the through hole provided in the sealing means on the electrode lead side, and a step having a high elastic modulus in the through hole A tube mounting step of mounting a tube made of a material, and inserting the electrode lead-out means into a through-hole with a tube formed in the tube mounting step, pulling out the external connection portion from the through-hole, and rounding the inside of the tube. The method is characterized by including an electrode lead-out step of fitting the rod portion.

According to this method, the electrolytic capacitor according to the first to tenth aspects can be easily and efficiently manufactured. That is, the operation of inserting a tube made of a material having a high elastic modulus into the through-hole and the operation of inserting the electrode lead-out means into the resulting through-hole with a tube are extremely easy and efficient operations. . In addition, since the step forming step forms an inwardly projecting step on the inner surface of the through hole on the electrode lead side, even if the tube is pressed when the electrode lead means is inserted, the tube is locked by the step. Therefore, the tube can be prevented from dropping out of the through hole.

According to a twelfth aspect of the present invention, there is provided a method of manufacturing an electrolytic capacitor, comprising: forming a capacitor element by winding a bipolar electrode foil connected to an electrode lead means through a separator; The method includes an assembling step of sealing the inside of the cylindrical outer case. Further, as the electrode lead means, an electrode lead means comprising a flat plate part for internal connection, a round bar part for penetrating the sealing means, and an external connection part is used. In such a manufacturing method, a locking member attaching step of arranging a locking member having an opening smaller in diameter than the diameter of the through-hole on the electrode lead-out side of the sealing means; A tube mounting step of mounting a tube made of a material having a high rate, and inserting the electrode lead-out means into a through-hole with a tube formed by the tube mounting step, and pulling out the external connection portion from the through-hole; Characterized by having an electrode lead-out step of fitting a round bar portion into the inside.

According to this method, similarly to the electrolytic capacitor according to the eleventh aspect, the electrolytic capacitor according to the first to tenth aspects can be easily and efficiently manufactured. In addition, when the tube is mounted in the through hole, the locking member is provided on the electrode drawing side of the closing means, so that even if the tube is pressed when the electrode drawing means is inserted, the tube is kept by the locking member. Since the tube is locked, it is possible to prevent the tube from dropping out of the through hole. Further, after the tube is mounted in the through hole, the locking member is removed, so that an electrolytic capacitor having the same shape as the conventional one can be obtained.

According to a thirteenth aspect of the present invention, there is provided a method for manufacturing an electrolytic capacitor according to the eleventh or twelfth aspect, wherein the sealing means is formed around a first sealing means made of a hard material. And a second tube mounting step of mounting a second sealing means made of a flexible material. According to this method,
The sealing means according to claim 6 can be easily created.

According to a fourteenth aspect of the present invention, in the method for manufacturing an electrolytic capacitor according to any one of the eleventh to thirteenth aspects, the tube mounting step includes a step of mounting a tube longer than a dimension used at the time of mounting. The method further includes a step of continuously supplying the tube by using the tube and sequentially cutting the tube to a use size. According to this method, it is possible to continuously supply the tube at an appropriate speed using a long tube in reel units, and insert the electrode lead-out means into the tube while sequentially cutting the tube to the size used. Therefore, the tube mounting operation can be efficiently performed continuously using a simple production machine. Further, when the present invention is applied to the second tube mounting step, the sealing means can be efficiently formed.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of an electrolytic capacitor according to the present invention and a method for manufacturing the same (hereinafter, referred to as an embodiment) will be specifically described with reference to the drawings.
The same members as those of the conventional type shown in FIG. 9 are denoted by the same reference numerals, and description thereof will be omitted.

[1. First Embodiment] [1-1. Configuration of Electrolytic Capacitor] FIG. 1 is a sectional view showing a configuration of a first embodiment of an electrolytic capacitor according to the present invention. That is, in the present embodiment, as shown in FIG. 1, a capacitor element 2 formed by winding a bipolar electrode foil to which a lead terminal (electrode lead means) 1 is connected via a separator is a bottomed cylinder made of aluminum or the like. It is housed in an outer case 3 in a shape of a letter. The sealing body 10 for sealing the opening of the outer case 3 is formed of a single member as shown in FIG. 1, and has a through hole 11 for leading a lead terminal at a predetermined position. And this through hole 11
A step portion 12 protruding inward is formed on the inner surface on the lead terminal lead-out side (the upper side in the figure). The step portion 12 functions as a locking portion for suppressing the movement of the tube 13 as described later.

The hard material constituting the sealing member 10 is a resin material containing a fluororesin, polyphenylene sulfide, nylon, phenol, epoxy, polysulfone, polyimide, polyamideimide, polyoxybenzylene polyethylene, polypropylene, and polycarbonate. Group, a group of metal materials including aluminum, tantalum, magnesium, copper, nickel, titanium, or alloys thereof, hard rubber, ceramic, glass,
The material selected from the following is used. In this case, when a metal material is used, in order to secure insulation between the lead terminal 1 and the capacitor element 2, a resin film or an oxide film made of epoxy resin, nylon resin, or the like is formed on the surface of the metal material. Is formed.

Further, as shown in FIG. 2, a tube 1 made of a material having a high elastic modulus is
3, the lead terminal 1 is inserted into the tube 13, and the external connection portion 1c of the lead terminal is inserted from the other side.
Is drawn out so that the tube 13 and the round bar portion 1b come into close contact with each other. Note that, in this case, the inner surface of the through hole 11 and the tube 13 are not bonded, and when the tube 13 moves in the through hole 11 at the time of insertion of the lead terminal, the step 12 inhibits the movement of the tube 13. It functions as a locking part. The opening of the outer case 3 is sealed by the tube 13 and the sealing body 10, and the tip of the opening abuts on the sealing body 10 by drawing.

FIGS. 3A and 3B are views showing the configuration of the lead terminal 1, wherein FIG. 3A is a plan view, FIG. 3B is a front view, and FIG. 3C is a side view. As shown in FIG.
The tube 1 includes a flat plate portion 1a for internal connection, a round bar portion 1b for penetrating the sealing body, and an external connection portion 1c, of which the round bar portion 1b is mounted in the through hole 11.
3.

The material constituting the tube 13 is rubber having a high elastic modulus, a fluororesin, a shrinkable tube, polyethylene, polyester, polyimide, polyamide,
A material selected from nylon, polyamideimide, silicone resin, silicone rubber, poly-4-methylpentene-1 (crystalline polyolefin), and ethylene vinyl alcohol is used.

In this case, the dimensional relationship among the tube 13, the through hole 11, and the round bar 1b is as shown in FIG. 4 in order to enhance the adhesion between the round bar 1b and the sealing body 10. That is, assuming that the diameter of the through hole 11 formed in the sealing body 10 is D ₁ , the diameter of the round bar is D ₂ , and the thickness of the tube is t, these relations are expressed by the following equations. Incidentally, the following equation, in other words, in a state of mounting the tube 13 in the through hole 11, the inner diameter of the tube 13 which means that smaller than the diameter D ₂ of the round bar part 1b.

[0034]

D ₁ −D ₂ <t × 2 Further, by making the inner diameter (D ₃ ) of the tube 13 smaller than the diameter of the round bar, the adhesion between the round bar portion 1b and the tube 13 can be further enhanced. However, in this case, the relationship between the diameter of the round bar and the inner diameter of the tube is expressed by the following equation.

[0035]

D ₂ > D ₃ [1-2. Manufacturing Process of Electrolytic Capacitor] The electrolytic capacitor having the above configuration is specifically manufactured by the following procedure. First, the flat plate portions 1a of the pair of lead terminals 1 are
The capacitor element 2 is formed by connecting each of the bipolar electrode foils and winding the bipolar electrode foils via a separator.

Next, as shown in FIG. 2, a tube 13 made of a material having a high elastic modulus is attached to the inner periphery of the through hole 11 formed in the sealing body 10. Specifically, using an appropriate production machine and a long tube material in reel units, the tube material is continuously supplied at an appropriate speed. Then, a predetermined tube 13 is formed by sequentially cutting to a use size as shown in FIG. 2, and this tube 13 is continuously mounted on the inner periphery of the through hole 11 formed in the sealing body 10 (tube mounting step). ).

Subsequently, for each of the pair of lead terminals 1 protruding from the capacitor element 2, the distal end of the external connection portion 1c is inserted into the tube 13, and the lead terminal 1 and the tube 13 are relatively moved. After that, the entire external connection portion 1c is pulled out of the tube 13, and the tube 13 is brought into close contact with the outer periphery of the round bar portion 1b of the lead terminal 1.
Thereafter, the capacitor element 2 integrated with the sealing body 10 is housed in the outer case 3, and the sealing body 10 is attached to the opening of the outer case 3 to seal the outer case 3. In this case, as shown in FIG. 1, drawing is performed on the opening of the outer case 3, and the tip of the opening is brought into contact with the sealing body 10.

[1-3. Operation / Effect] The operation / effect of the electrolytic capacitor of the present embodiment having the above configuration is as follows. First, a hard resin, a metal,
Since it is made of a hard material such as hard rubber, ceramic, and glass, gas permeability can be reduced. Further, a tube 13 made of a material having a high elastic modulus such as rubber, resin, or a shrink tube is attached to the inner surface of the through hole 11 formed in the sealing body 10, and the lead terminal 1 is inserted into the tube 13. Since the lead terminal is pulled out from the through hole 11 of the sealing body 10, the airtightness of the lead terminal lead-out portion in the sealing body 10 can be improved by the tube 13. That is, the tube 13 is mounted on the side of the through hole 11 formed in the sealing body 10 in advance.
When the lead terminal 1 is inserted, it is easily deformed so as to extend in the insertion direction.

As described above, when the lead terminal 1 is inserted, the tube 13 and the sealing body 10 slide due to the radial compression of the tube 13 and the tube 13 extends in the length direction, so that the volume of the tube 13 changes. do not do. Therefore, the elasticity of the tube 13 is utilized, and the pressing force at the time of inserting the lead terminal 1 is reduced, so that the work of inserting the lead terminal 1 into the tube 13 is facilitated. The tube 13
As a result, the stress is diffused, and sufficient adhesion between the tube 13 and the round bar portion 1b of the lead terminal 1 is obtained. In this case, the inner peripheral surface of the tube 13 and the outer peripheral surface of the round bar portion 1b can be securely brought into close contact with each other over the entire contact area due to the dimensional relationship between the tube 13 and the round bar portion 1b. Airtightness can be increased.

Since the stepped portion 12 is formed on the inner surface of the through hole 11 on the lead terminal lead-out side, the stepped portion 12 is formed to protrude inward. Since the tube 13 is locked by the portion 12, the tube 13 does not fall out of the through hole 11.

Also, when the tube 13 is inserted into the through hole 11 of the sealing body 10, the tube 13 is easily deformed similarly, and sufficient adhesion between the tube 13 and the through hole 11 is obtained. Since the tube 13 is easily deformed as described above, the tube 13 having an outer diameter larger than the diameter of the through hole 11 can be used as described above. Since the surface and the inner peripheral surface of the through hole 11 can be securely brought into close contact with each other over the entire contact region, the airtightness of this portion can be improved.

Further, as described above, when the round bar portion 1b of the lead terminal 1 is inserted into the through hole 11 of the sealing body 10, the tube 13 closely contacting the round bar portion 1b extends in the insertion direction. By doing so, sufficient elasticity can be obtained,
By utilizing this elasticity, even a tube having a low gas permeability and a high elastic modulus (high hardness) can be easily inserted.
Therefore, depending on the material of the tube 13, the gas permeability can be made sufficiently low, and high airtightness can be obtained. In addition, in the present embodiment, since the tip of the opening of the outer case 3 is in contact with the sealing body 10, the pressing of the sealing body 10 is strong, and the sealing body 10 is Jumping out of the case 3 can be suppressed.

On the other hand, in the above-described manufacturing process,
Work for mounting the tube 13 in the through hole 11 of the sealing body 10 made of a hard material,
Is very easy and efficient, so that an electrolytic capacitor can be easily and efficiently manufactured.

In particular, by using an appropriate production machine and a long tube material in reel units, the tube material is continuously supplied at an appropriate speed, and is sequentially cut into the used dimensions to form a predetermined tube 13. Then, this tube 13 is sealed
Since the tube 13 can be continuously mounted on the inner periphery of the through hole 11 formed at 0, the efficiency of the tube 13 mounting operation is improved. In this case, since the tubes need only be supplied in reel units, the production efficiency can be improved from this point as well. further,
Since such a tube 13 can be easily and efficiently produced by continuous production, it can contribute to improvement of production efficiency also from this point.

[2. Second Embodiment] [2-1. Configuration of Electrolytic Capacitor] FIG. 5 is a sectional view showing the configuration of the second embodiment of the electrolytic capacitor according to the present invention. That is, in the present embodiment, as shown in FIG. 5, the sealing body 20 for sealing the opening of the outer case 3 is formed of a single member, and the through hole 21 for leading out the lead terminal is provided at a predetermined position. Is formed. The inner diameter of the through hole 21 is different from that of the first embodiment, and is equal throughout the length thereof. The other configuration is the same as that of the above-described first embodiment, and the description is omitted.

[2-2. Manufacturing Process of Electrolytic Capacitor] The electrolytic capacitor having the above configuration is specifically manufactured by the following procedure. First, the flat plate portions 1a of the pair of lead terminals 1 are connected to each of the bipolar electrode foils.
To form

Next, as shown in FIG. 6, a tube 13 made of a material having a high elastic modulus is attached to the inner periphery of the through hole 21 formed in the sealing body 20. In this case, the sealing body 2
0, on the lead terminal lead-out side, a locking member 22 having an opening 23 having a diameter smaller than the diameter of the through hole 21 is inserted into the through hole 21.
When the tube 13 is pressed in the insertion direction when the lead terminal 1 is inserted, the tube 13 is prevented from dropping out of the through hole 21 by contacting the opening 13 with the opening 23 concentrically. Specifically, using a suitable production machine and a long tube material in reel units, the tube material is continuously supplied at an appropriate speed. Then, a predetermined tube 13 is formed by sequentially cutting into a use size as shown in FIG. 6, and this tube 13 is continuously attached to the inner periphery of a through hole 21 formed in the sealing body 20.

Subsequently, for each of the pair of lead terminals 1 protruding from the capacitor element 2, the distal end of the external connection portion 1c is inserted into the tube 13, and the lead terminal 1 and the tube 13 are relatively moved. After that, the entire external connection portion 1c is pulled out of the tube 13, and the tube 13 is brought into close contact with the outer periphery of the round bar portion 1b of the lead terminal 1.
Thereafter, the locking member 22 disposed on the lead terminal pull-out side of the sealing body 20 is removed, and the capacitor element 2 integrated with the sealing body 20 is stored in the outer case 3. The exterior case 3 is sealed by mounting the body 20.

[2-3. Operation / Effect] The operation / effect of the electrolytic capacitor of the present embodiment having the above configuration is as follows. In this embodiment, the shape of the through hole 21 formed in the sealing body 20 and the tube 1 in the through hole 21 are different.
The only difference from the first embodiment is that the locking member 22 is used in the step of attaching the third member 3. Therefore, the operation and effects unique to the second embodiment will be described here.

First, the through-hole 21 formed in the sealing body 20
Are set to be equal in the entire length direction, so that the step of forming the through hole 21 in the sealing body 20 is simplified as compared with the first embodiment. When the tube 13 is mounted in the through hole 21, the locking member 22 having an opening 23 having a diameter smaller than the diameter of the through hole 21 is provided on the lead terminal lead-out side of the sealing body 20. 2
3 is arranged concentrically, even if the tube 13 is pressed in the insertion direction when the lead terminal 1 is inserted, the movement of the tube 13 is suppressed by the locking member 22, and the tube 13 is moved from the through hole 21. Dropping is prevented.
Further, after the tube 13 is mounted in the through hole 21,
Since the locking member 22 is removed, it is possible to obtain an electrolytic capacitor having the same shape as the conventional one.

[3. Other Embodiments] The present invention
The present invention is not limited to the embodiments described above, and various other embodiments can be implemented within the scope of the present invention. First, in the above-described embodiment, specific materials are listed as the materials having a high elastic modulus that constitute the tube and the sealing body. However, the materials are not limited to these, and various other materials are used. be able to.

In the above-described embodiment, the sealing members 10 and 20 are formed of a single member. However, as shown in FIG. Sealing plate (first sealing member)
30a and an elastic ring (second sealing member) 30b made of a flexible material and disposed on the outer periphery thereof. In this case, the inner diameter of the elastic ring 30b is smaller than the outer diameter of the sealing plate 30a.

With this configuration, even if the dimensions of the first sealing member 30a made of metal, resin or the like having a high elastic modulus are slightly varied, the second sealing member 30
Dimensional errors can be absorbed by the elasticity of b. As a result, the outer peripheral surface of the sealing body 30 and the inner peripheral surface of the opening of the outer case 3 can be securely brought into close contact with each other, so that the airtightness of this portion can be sufficiently ensured.

Further, a second sealing member 30b made of a flexible material such as an elastic ring is formed by cutting a long tube material to a predetermined size, and the first sealing member 30b is formed on the second sealing member 30b. If the sealing body 30 is formed by inserting the sealing member 30a, production efficiency can be improved. In addition, as a flexible material constituting the elastic ring,
Materials selected from the groups listed above for the tubes are used.

In the above-described embodiment, the through holes 11 and 21 formed in the sealing bodies 10 and 20 are configured so that their cross-sectional shapes are linear. However, the present invention is not limited to this. The appropriate shape can be appropriately selected. For example,
As shown in FIG. 8, the through hole 4 formed in the sealing body 40
1 may be composed of a linear portion 41a having a constant diameter and an insertion guide portion 41b which is inclined and spreads toward an opening end on the side where the lead terminal 1 is to be inserted. Thereby, the tube 13 can be easily inserted into the through hole 41. In this case, diameter d ₁ of the linear portion 41a of the through hole 41 has been smaller than the outer diameter d ₂ of the tube 13, the maximum diameter d ₃ of the insertion guide portion 41b is of the tube 13 It is larger than the outer diameter d _2.

As described above, in the present invention, the specific configuration of the sealing means can be freely selected, and in this connection, the specific hermetic structure between the outer case and the sealing means is also freely selected. It is possible. Further, specific dimensions, shapes, and materials of the outer case, the electrode lead-out means, and the like can be freely selected.

[0057]

The electrolytic capacitor according to the present invention as described above was tested in order to examine changes over time in electrical characteristics.
3 and the present invention using the sealing body 10 have the same configuration except for the sealing structure, and have the same rating of 16V-
47 μF (φ6.3 × 5 L) electrolytic capacitors were each manufactured. In this case, the tube 13 in the product of the present invention
A fluorine resin is used as the material of the sealing body 10, and the inner surface of the through hole 11 formed in the sealing body 10 and the tube 13 are used.
And is not glued. A 105 ° C. standing test and a 130 ° C.
As a result of performing a standing test at ℃, the results shown in the following Tables 1 and 2 were obtained.

[0058]

[Table 1]

[Table 2]

As is clear from Table 1, in the case of standing at 105 ° C., the weight loss of the conventional product reached −2.7 mg as soon as 500 hours had passed, and the weight loss had reached as early as 2000 hours. The amount has reached -12 mg. In addition, the capacity change rate is-
The value is greatly reduced to 15%, and the value of tan δ is also significantly increased to about 5 times the initial value. On the other hand, in the product of the present invention, even after the lapse of 2000 hours, the weight loss was only -3 mg, the capacity change rate was about -7%, and tan δ was slightly increased from the initial value. is there.

Thus, in the 105 ° C. standing test,
The conventional product shows the characteristic deterioration as early as 500 hours later, and shows a remarkable property decrease after 2000 hours. On the other hand, the product of the present invention is close to the initial value even after 2000 hours. Maintains excellent values.

As is clear from Table 2, at 130 ° C.
In the case of standing, in the case of the conventional product, the weight loss reached -11 mg as soon as 500 hours had elapsed, the rate of change in capacity was greatly reduced to -13%, and the initial value of tan δ was also about 4.5. It has risen significantly twice. And, at the time of the lapse of 1000 hours, the weight loss amount is -18 m
g, and the rate of change in capacity is remarkably reduced to -85%, making it unusable. Further, at the time of lapse of 2000 hours, the weight loss amounted to -25 mg, and the capacity change rate and tan δ could not be measured.

On the other hand, in the product of the present invention, 10
Even after the lapse of 00 hours, the weight loss amount is only -2.2 mg, the capacity change rate is about -6%, and tan δ also slightly increases from the initial value. further,
Even after 2,000 hours, the weight loss is -4.2 mg.
And the capacity change rate was about -8%, and tan δ was about 1.7 times the initial value.

Thus, in the 130 ° C. standing test,
The conventional product shows a remarkable deterioration in characteristics as early as 500 hours later, and cannot be used after 1000 hours, whereas the product of the present invention has an excellent near initial value even after 1000 hours. Maintain the value.

From the above, it is clear that the product of the present invention has excellent life characteristics as compared with the conventional product, and in particular, has excellent heat resistance life characteristics. This means that tube 13
And the sealing structure according to the present invention using the sealing body 10,
This demonstrates that an electrolytic capacitor having stable and high life characteristics can be obtained.

[0065]

As described above, according to the present invention,
By inserting a tube in advance into the through hole of the sealing means made of a hard material and inserting the round bar part of the electrode lead-out means into this tube, it has a stable and high life characteristic, improving production efficiency and reducing manufacturing costs. An excellent electrolytic capacitor that can contribute to reduction can be provided. Another object of the present invention is to provide an excellent manufacturing method capable of efficiently manufacturing such an excellent electrolytic capacitor at low cost.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of a first embodiment of an electrolytic capacitor according to the present invention.

FIG. 2 is a cross-sectional view showing a state in which a lead terminal is inserted into a through hole in which a tube is mounted in the electrolytic capacitor of FIG.

3A and 3B are diagrams showing lead terminals of the electrolytic capacitor of FIG. 1, wherein FIG. 3A is a plan view, FIG. 3B is a front view, and FIG. 3C is a side view.

FIG. 4 is an explanatory view showing a dimensional relationship of a through-hole formed in a sealing body, a tube, and a round bar portion of a lead terminal in the electrolytic capacitor of FIG. 1;

FIG. 5 is a sectional view showing a configuration of a second embodiment of the electrolytic capacitor according to the present invention.

FIG. 6 is a cross-sectional view showing a state in which a lead terminal is inserted into a through hole in which a tube is mounted in the electrolytic capacitor of FIG.

FIG. 7 is a sectional view showing another configuration of the sealing body of the electrolytic capacitor according to the present invention.

FIG. 8 is a cross-sectional view showing another configuration of a through hole formed in the sealing body of the electrolytic capacitor according to the present invention.

FIG. 9 is a sectional view showing a structure of a conventionally used electrolytic capacitor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Lead terminal 1a ... Flat plate part 1b ... Round bar part 1c ... External connection part 2 ... Capacitor element 3 ... Exterior case 10 ... Sealing body 11 ... Through hole 12 ... Step part 13 ... Tube 20 ... Sealing body 21 ... Through hole 22 ... locking member 23 ... opening 30 ... sealing body 30a ... first sealing member (sealing plate) 30b ... second sealing member (elastic ring) 40 ... through hole 40a ... linear part 40b ... insertion guide part

Claims (14)

[Claims] 1. A capacitor element in which bipolar electrode foil to which an electrode lead-out means is connected is wound via a separator, a bottomed cylindrical outer case for housing the capacitor element,
A sealing means attached to an opening of the outer case, wherein the electrode lead means comprises a flat plate part for internal connection, a round bar part for penetrating the sealing means, and an external connection part. In the electrolytic capacitor drawn out of the outer case through the through hole provided in the sealing means, a tube made of a material having a high elastic modulus is mounted in the through hole provided in the sealing means, Wherein the round bar portion of the electrode lead-out means is inserted. 2. A capacitor element formed by winding a bipolar electrode foil to which an electrode lead-out means is connected via a separator, a bottomed cylindrical outer case for housing the capacitor element,
A sealing means attached to an opening of the outer case, wherein the electrode lead means comprises a flat plate part for internal connection, a round bar part for penetrating the sealing means, and an external connection part. In the electrolytic capacitor drawn out of the outer case through the through-hole provided in the sealing means, a step portion protruding inward is formed on an inner surface of the through-hole provided in the sealing means on the electrode lead-out side. An electrolytic capacitor, wherein a tube made of a material having a high elastic modulus is mounted in the through hole, and a round bar portion of the electrode lead means is inserted into the tube. 3. The electrolytic capacitor according to claim 1, wherein an inner diameter of the tube is smaller than an outer diameter of a round bar portion of the electrode lead-out means. 4. An outer diameter of the tube is larger than a diameter of a through hole provided in the sealing means when the tube is mounted on a round bar portion of the electrode drawing means. The electrolytic capacitor according to any one of claims 1 to 3. 5. A method according to claim 1, wherein a diameter of an opening end of said through hole on an insertion side of said electrode lead-out means is larger than a diameter of a center part thereof. The electrolytic capacitor according to claim 1. 6. The sealing means according to claim 1, wherein said sealing means is made of a hard material.
6. The electrolytic capacitor according to claim 1, comprising a sealing member made of a flexible material and a second sealing member attached to the outer periphery of the sealing member. 7. . 7. The electrolytic capacitor according to claim 6, wherein the second sealing member is formed in a tube shape, and has an inner diameter smaller than an outer diameter of the first sealing member. 8. The material having a high elastic modulus is rubber, fluororesin, shrink tube, polyethylene, polyester, polyimide, polyamide, nylon, polyamideimide,
8. A material selected from the group consisting of silicone resin, silicone rubber, poly-4-methylpentene-1 (crystalline polyolefin), and ethylene vinyl alcohol. An electrolytic capacitor according to item 1. 9. The method according to claim 8, wherein the sealing means is a fluororesin, polyphenylene sulfide, nylon, phenol, epoxy, polysulfone, polyimide, polyamideimide,
Polyoxybenzylene polyethylene, polypropylene,
It is composed of materials selected from a group of resin materials including polycarbonate, a group of metal materials including aluminum, tantalum, magnesium, copper, nickel, titanium, or alloys thereof, hard rubber, ceramic, and glass. The electrolytic capacitor according to any one of claims 1 to 8, wherein: 10. The electrolytic capacitor according to claim 1, wherein a tip of the outer case opening is in contact with the sealing means by drawing. 11. An element forming step of forming a capacitor element by winding a bipolar electrode foil connected to an electrode lead-out means via a separator, and an assembling step of sealing the capacitor element in a bottomed cylindrical outer case. A method for producing an electrolytic capacitor using an electrode lead means comprising: a flat plate part for internal connection, a round bar part for penetrating a sealing means, and an external connection part, wherein the electrode lead means is provided in the sealing means. Forming a step that protrudes inward on the inner surface of the through-hole on the electrode lead-out side, mounting a tube made of a material having a high elastic modulus in the through-hole, and mounting the tube. Insert the electrode lead-out means into the through-hole with the tube formed by the process, pull out the external connection part from this through-hole, and A method for manufacturing an electrolytic capacitor, comprising an electrode lead-out step of fitting a round bar portion into an electrode. 12. An element forming step of forming a capacitor element by winding a bipolar electrode foil connected to an electrode lead-out means through a separator, and an assembling step of sealing the capacitor element in a bottomed cylindrical outer case. A method for producing an electrolytic capacitor using an electrode lead means comprising: a flat plate part for internal connection, a round bar part for penetrating a sealing means, and an external connection part as the electrode lead means; On the side, a locking member mounting step of disposing a locking member having an opening smaller in diameter than the diameter of the through hole, and a tube mounting step of mounting a tube made of a material having a high elastic modulus in the through hole, An electrode lead-out means is inserted into a through hole with a tube formed in the tube mounting step, and the external connection portion is pulled out from the through hole, and A method for manufacturing an electrolytic capacitor, comprising an electrode lead-out step of fitting a round bar portion into a tube. 13. A second tube mounting step of mounting a second sealing means made of a flexible material on an outer periphery of the first sealing means made of a hard material to form the sealing means. The method for manufacturing an electrolytic capacitor according to claim 11 or 12, wherein: 14. The method according to claim 14, wherein the tube mounting step further includes a step of continuously supplying the tube by using a tube having a length longer than a used size at the time of mounting, and sequentially cutting the tube to a used size. Claims 11 to 1
4. The method for producing an electrolytic capacitor according to any one of items 3 to 5.