JPH09246120A - Aluminum electrolytic capacitor and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aluminum electrolytic capacitor adapted for the use in various electronic equipment in which improvement in insulation reliability, improvement in productivity, reduction in cost, and improvement in mounting stability at the time of mounting are realized, and its manufacturing method. SOLUTION: A capacitor element 4 having a lead wire 5 is inserted together with an electrolyte solution 9 and a sealing rubber 6 into an aluminum case 3. A sealing portion 7 is provided by bending and pressing process so that the case is sealed. A resin-molded body 1 which has an adhesive layer 2 provided on the inner surface thereof and which has an insertion hole 16 for the lead wire 5 provided on the bottom surface of a cylindrical recessed part closed at one end is pressed into the sealing part 7 and adhered by heating. With this structure, insulation property may be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a compact aluminum electrolytic capacitor used in various electronic devices and a method for manufacturing the same.

[0002]

2. Description of the Related Art As shown in the cross-sectional view of FIG. 8, a conventional aluminum electrolytic capacitor has a structure and a manufacturing method thereof, in which a capacitor element 28 in which a lead wire 29 is drawn out from one end is
After inserting the electrolytic solution 31 and the sealing rubber 27 into the aluminum case 26, and bending and drawing the aluminum case 26 in the sealing rubber 27 portion to seal, the polyvinyl chloride (hereinafter referred to as PV
In most of the cases, the heat-shrinkable tube 25 made of a material (referred to as C) covers the outer periphery of the heat-shrinkable tube 25.

In addition, as shown in FIG.
As shown in the cross-sectional view, the aluminum case 33 coated with the nylon resin coating 32 is bent and drawn at a low speed so as not to be damaged during processing, and is sealed. By using a sealing rubber 34 having a tall and protruding convex portion, or by bending the lead wire 35 into a U-shape, a mounting / fixing position on a printed circuit board or the like to be mounted is set or regulated. The structure was used.

[0004]

However, in the conventional structure and manufacturing method described above, PV has been adopted in recent years because of environmental protection measures.
There is a problem in that the use of C is restricted, and because the PVC heat-shrinkable tube 25 is deformed or cracked due to atypical shrinkage during heat shrinkage, the insulation is poor.

Further, the cost of the aluminum case 33 coated with the nylon resin film 32 and the sealing rubber 34 having a convex portion becomes high, and the aluminum case 33 is bent at a low speed and the lead wire 35 is bent in a U shape. Had problems such as low man-hours, low productivity, and poor positioning and mounting stability in mounting and mounting on a printed circuit board or the like.

The present invention is intended to solve such a conventional problem, and it is possible to improve the insulation reliability of an aluminum electrolytic capacitor, improve productivity, reduce costs, and improve stability during mounting. An object of the present invention is to provide an aluminum electrolytic capacitor and a method for manufacturing the same.

[0007]

In order to solve the above-mentioned problems, an aluminum electrolytic capacitor and a method for manufacturing the same according to the present invention are constructed by bending an aluminum case at a portion having a sealing rubber from which a lead wire of the aluminum electrolytic capacitor is drawn out. In the processed sealing portion, a thermoplastic resin molded body having an adhesive layer on the inner surface side and having a lead wire insertion hole in the bottom surface of a cylindrical concave portion having one end opened is mounted.

According to this invention, the insulation reliability is high,
It is possible to obtain an aluminum electrolytic capacitor that is excellent in productivity and cost and has good mounting stability during mounting.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention comprises a capacitor element in which an anode foil and a cathode foil from which lead wires for external connection are respectively drawn are wound with electrolytic paper together with an electrolytic solution. The bottomed cylindrical aluminum case loaded inside is inserted into the opening of this aluminum case by inserting the lead wire, and the elasticity is utilized by bending the opening of the aluminum case and drawing the peripheral surface. A sealing rubber for sealing,
The lead wire is formed in a cylindrical shape having a bottom through which the lead wire is inserted, and is constituted by a resin molded body that is fixed so as to cover the sealing portion of the aluminum case with an adhesive layer provided on the inner surface. The reliability is improved, and the mounting is stable.

According to a second aspect of the present invention, in the first aspect of the invention, the inner diameter of the fixing portion of the resin molded body to the aluminum case is set to be slightly smaller than the outer diameter of the aluminum case. It has the effect of improving the mounting adhesion.

According to a third aspect of the present invention, in the first or second aspect of the invention, the lead wire insertion hole provided in the resin molded body is slightly larger than the pitch interval between the pair of lead wires drawn out from the capacitor element. One large or a hole slightly larger than the wire diameter of the lead wire is provided in accordance with the pitch of the lead wire, and has an effect of improving insertability.

According to a fourth aspect of the invention, in the invention according to any one of the first to third aspects, a plurality of protrusions are provided on the periphery of the lead wire insertion hole provided in the resin molded body. It has an effect of preventing adhesion and facilitating separation.

According to a fifth aspect of the invention, in the invention according to any one of the first to fourth aspects, a convex protrusion protruding toward the capacitor element is provided on the bottom surface of the resin molded body so as to pass through the center of the bottom surface. It has a structure, and has an effect of improving separability and stabilizing.

According to a sixth aspect of the present invention, in the invention according to any one of the first to fifth aspects, the material of the resin molding is
The thermoplastic resin has a melting point of 230 ° C. or higher and is selected from the group consisting of polyethylene terephthalate, polynaphthalene phthalate, polyphenyl sulfone, polyether ether ketone, liquid crystal polymer, and 6-nylon, which improves heat resistance. Have an effect.

According to a seventh aspect of the invention, in the invention according to any one of the first to sixth aspects, as a material for the adhesive layer formed on the inner surface of the resin molded body, a polyester type, a polyamide type, or an ethylene vinyl acetate type is used. It is configured to use a hot melt adhesive, and has an action of facilitating adhesion and strengthening.

According to an eighth aspect of the present invention, in the invention according to any one of the first to seventh aspects, a capacitor is obtained by winding an anode foil and a cathode foil, from which lead wires for external connection are respectively drawn, through electrolytic paper. After manufacturing the element, insert this capacitor element into a bottomed cylindrical aluminum case filled with electrolyte, and then insert a sealing rubber with a hole through which the lead wire of the capacitor element is inserted into the upper part of the inner circumference of the aluminum case. And then bend the open end of the aluminum case toward the inner peripheral direction and press the upper part of the outer peripheral surface of the aluminum case toward the inner peripheral direction to form the sealing part, pressurize the sealing rubber and seal it. A resin molded body having a cylindrical shape with a bottom provided with a hole through which the lead wire of the capacitor element is inserted is mounted so as to cover the sealing portion of the aluminum case, and is formed on the inner surface of the resin molded body. Is obtained by a manufacturing method as fixed via an adhesive layer, in addition to the effect of claim 1, it has the effect of improving productivity.

A ninth aspect of the present invention is the method according to the eighth aspect of the present invention, in which the resin molded body is molded by embossing at room temperature or heating, and the accuracy is good and the productivity is improved. Has the effect of.

According to a tenth aspect of the present invention, in the invention of the eighth aspect, a plurality of resin molded bodies are provided on the band-shaped film material by molding, and after a plurality of aluminum electrolytic capacitors are inserted therein, the resin molded body is formed. It is a manufacturing method in which it is bonded and fixed at the same time by putting or passing it in a temperature tank having a temperature above the melting point of the adhesive of the formed adhesive layer and below the melting point of the film material. It has the effect of not occurring.

According to an eleventh aspect of the invention, in the invention of the eighth aspect, the fixing of the resin molded body and the aluminum case is performed by using any heating means of ultrasonic wave, electromagnetic induction, soft beam, heater or laser. Thus, the manufacturing method is such that each aluminum electrolytic capacitor is heated, and has the effect of improving productivity and automating production.

An embodiment of the present invention will be described below with reference to the drawings. 1 is a sectional view showing the structure of the aluminum electrolytic capacitor in the same embodiment, FIG. 2 is a manufacturing process diagram showing a processing method of a thermoplastic resin molding used in the same capacitor, and FIGS. 3 to 7 are the same. It is the top view and sectional view which showed the composition of the thermoplastic resin molding.

As shown in FIG. 1, first, a capacitor element 4 in which a lead wire 5 made of a metal material is drawn out from one end, an electrolyte 9 and a sealing rubber 6 made of an elastic insulating material in which the lead wire 5 is inserted. As aluminum material or about 30μ
Insert the resin coating 8 of nylon material of m from an aluminum material through the opening of a cylindrical aluminum case 3 with a bottom, and bend and squeeze the opening end of the aluminum case 3 that the sealing rubber 6 contacts. By doing so, the sealing portion 7 is provided and sealing (sealing) is performed.

Then, an adhesive layer 2 is formed by applying a hot melt adhesive on the inner surface, and a cylindrical insertion concave portion having one end closed and an insertion hole 16 for the lead wire 5 are simultaneously embossed on the bottom surface. After being press-fitted into the resin molded body 1, the resin molded body 1 is bonded and fixed by heating and cut at the separating portion 10 to be completed.

Next, the finished product size is 5 mm in outer diameter and 6 mm in height.
The manufacturing method of the aluminum electrolytic capacitor will be described with reference to FIG.

In FIG. 2, a polyethylene resin having a melting point of 265 ° C. and a thickness of 100 μm, which is a thermoplastic resin having a melting point of 230 ° C. or more, is used as an embossing material, for example, a polyethylene terephthalate (hereinafter referred to as PET) film (for example, A
-PET [manufactured by Teijin Co., Ltd.] is coated on one side with a polyester hot melt adhesive (for example, Aron melt PES2).
25 [Toagosei Kagaku] melting point, 115 ° C) approx. 100μ
A hot melt coater (not shown) is applied to a thickness of m to form the adhesive layer 2, and the adhesive film 2 is cut to a width of about 10 mm to produce the strip-shaped film material 11.

Next, at the center of the strip-shaped film material 11, there is provided an insertion hole 16 for the lead wire 5 having a diameter of 3 mm which constitutes the resin molding 1, and one end having an inner diameter of 5.2 mm and a depth of 2 mm. The closed cylindrical insertion recess 13 and the positioning guide hole 12 having a diameter of 1 mm are simultaneously formed by an embossing process so that the adhesive layer 2 becomes the inner surface of the insertion recess 13 at a pitch of 8 mm.

Then, the lead wire 5 is inserted into the insertion recess 13 formed by embossing the aluminum electrolytic capacitor 14.
Is inserted into the insertion hole 16 and press-fitted to form a strip-shaped film carrier, which is placed in an infrared heating furnace (not shown) at about 150 ° C., left for 30 minutes and then cooled, and then inserted into the aluminum electrolytic capacitor 14. The concave portions 13 are collectively bonded and fixed.

Subsequently, the band-shaped film material 1 is cut by using the positioning guide hole 12 as a reference and cutting it with an outer diameter of 5.4 mm.
The aluminum electrolytic capacitor 14 is completed by cutting it off from 1.

Further, there is no change in capacitance, dielectric loss tangent (tan δ) and leak current of electric characteristics after completion of the aluminum electrolytic capacitor manufactured in this way, and the dielectric breakdown voltage is about 15 kV. Met.

FIGS. 3 to 7 show specific examples of the structure of the above-mentioned insertion concave portion 13, in which the insertion holes 16 slightly larger than the pitch of the lead wires 5 are provided (FIG. 3) and the lead wires 5.
With two insertion holes 17 having a diameter slightly larger than the diameter of the lead wire 5 at the pitch interval of the lead wire 5 (FIG. 4), gas generated by soldering at the time of mounting on the insertion hole 16 and its surroundings, such as a printed circuit board. 4 with gas venting protrusions 18 on the upper surface (FIG. 5), similarly with the gas venting protrusions 18 on the upper surface (FIG. 6) and the insertion hole 17 and the insertion hole 17 for the lead wire 5. The lead wire 5 has a storage groove portion 19 (FIG. 7) and the like.

The heating for adhering the aluminum electrolytic capacitor 14 and the insertion concave portion 13 may be performed by means other than the above, such as ultrasonic heating, electromagnetic induction heating, and soft beam heating. Bonding may be performed, and further, individual heat bonding may be performed after the aluminum electrolytic capacitor with the resin molded body 1 is separated from the band-shaped film material 11 first.

As the adhesive for forming the adhesive layer 2, the above-mentioned other polyamide hot melt adhesive, polyolefin or modified polyolefin hot melt adhesive may be used.

As the thermoplastic resin, in addition to the above, polynaphthalene phthalate (melting point 275 ° C. PEN),
Any of polymethylpentene (melting point 230 ° C. TPX), polyphenylene sulfone (melting point 285 ° C. PPS), 66 nylon (melting point 260 ° C.), polyether ether ketone (melting point 295 ° C. PEEK) may be used.

[0033]

As described above, according to the aluminum electrolytic capacitor and the method for manufacturing the same of the present invention, the sealing portion of the aluminum electrolytic capacitor is provided with the adhesive layer on the inner surface side, and the lead wire is formed on the bottom surface of the cylindrical insertion concave portion having one end closed. By mounting the thermoplastic resin molding having the insertion hole, it is possible to obtain the advantageous effects of high insulation reliability, excellent productivity and cost, and improved mounting stability during mounting.

[Brief description of drawings]

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

FIG. 2 is a manufacturing process diagram illustrating a method for processing a resin molded body according to the same embodiment.

FIG. 3 is a plan view and a sectional view showing the structure of the resin molding.

FIG. 4 is a plan view and a sectional view showing the structure of the resin molding.

FIG. 5 is a plan view and a sectional view showing the structure of the resin molding.

FIG. 6 is a plan view and a sectional view showing the structure of the resin molding.

FIG. 7 is a plan view and a sectional view showing the structure of the resin molding.

FIG. 8 is a sectional view showing the structure of a conventional aluminum electrolytic capacitor.

FIG. 9 is a sectional view showing the structure of another conventional aluminum electrolytic capacitor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Resin molded body 2 Adhesive layer 3 Aluminum case 4 Capacitor element 5 Lead wire 6 Sealing rubber 7 Sealing part 8 Resin film 9 Electrolyte solution 10 Separation part 11 Strip film material 12 Guide hole 13 Insertion recess 14 Aluminum electrolytic capacitor 16 Insertion hole 17 insertion hole 18 degassing protrusion 19 storage groove

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tadahiro Nakamura 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Kazuya Kawahara, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (72) Inventor Takashi Nakamura 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Shigeyoshi Iwamoto 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (11)

[Claims] 1. A bottomed cylindrical aluminum case in which a capacitor element, in which an anode foil and a cathode foil from which lead wires for external connection are respectively drawn out, are wound with electrolytic paper and is loaded inside together with an electrolytic solution, Insert the lead wire into the opening of this aluminum case and fold the opening of the aluminum case and draw the peripheral surface to use the elasticity to seal the rubber and the hole through which the lead wire is inserted. An aluminum electrolytic capacitor, which is formed in a cylindrical shape having a bottom and is made of a resin molded body that is fixed by an adhesive layer provided on the inner surface so as to cover the sealing portion of the aluminum case. 2. The aluminum electrolytic capacitor according to claim 1, wherein an inner diameter of a portion of the resin molded body fixed to the aluminum case is slightly smaller than an outer diameter of the aluminum case. 3. A lead wire insertion hole provided in a resin molded body, which is slightly larger than a pitch interval of a pair of lead wires drawn out from a capacitor element, or a hole slightly larger than a wire diameter of the lead wire. The aluminum electrolytic capacitor according to claim 1, wherein the aluminum electrolytic capacitor is provided according to the pitch of the wires. 4. The aluminum electrolytic capacitor according to claim 1, wherein a plurality of protrusions are provided on the periphery of the lead wire insertion hole provided in the resin molded body. 5. The aluminum electrolytic capacitor according to claim 1, wherein a convex projection protruding toward the capacitor element is provided on the bottom surface of the resin molded body so as to pass through the center of the bottom surface. 6. The melting point of the resin molding material is 230.
The aluminum electrolytic capacitor according to any one of claims 1 to 5, wherein a thermoplastic resin selected from polyethylene terephthalate, polynaphthalene phthalate, polyphenyl sulfone, polyether ether ketone, liquid crystal polymer and 6-nylon at a temperature of not less than 0 ° C is used. 7. The hot melt adhesive of polyester type, polyamide type and ethylene vinyl acetate type is used as the material for the adhesive layer formed on the inner surface of the resin molded body. Aluminum electrolytic capacitor. 8. A capacitor element is manufactured by winding an anode foil and a cathode foil from which lead wires for external connection are respectively drawn out through electrolytic paper, and a capacitor element having a bottomed cylindrical shape filled with an electrolytic solution is formed. Insert it into the aluminum case, and then insert a sealing rubber with a hole through which the lead wire of the capacitor element is inserted into the upper part of the inner circumference of the aluminum case to bend the open end of the aluminum case in the inner circumference direction and The upper part of the outer peripheral surface is drawn toward the inner peripheral direction to form a sealing portion, thereby pressurizing and sealing the sealing rubber, and subsequently forming a bottomed cylindrical shape with a hole through which the lead wire of the capacitor element is inserted. The resin molded body thus formed is mounted so as to cover the sealing portion of the aluminum case, and is fixed via an adhesive layer formed on the inner surface of the resin molded body.
Any one of the methods for manufacturing an aluminum electrolytic capacitor. 9. The method for producing an aluminum electrolytic capacitor according to claim 8, wherein the resin molded body is molded by embossing performed at room temperature or heating. 10. A band-shaped film material is provided with a plurality of resin moldings by molding, and after inserting a plurality of aluminum electrolytic capacitors into the band-shaped film material, the melting point of the adhesive layer of the resin molding is equal to or higher than the melting point of the adhesive, and 9. The method for manufacturing an aluminum electrolytic capacitor according to claim 8, wherein the film material is placed or passed through a temperature tank having a melting point or lower to simultaneously bond and fix the film material. 11. The aluminum electrolytic capacitor is heated by fixing any one of ultrasonic molding, electromagnetic induction, soft beam, heater, and laser to fix the resin molded body and the aluminum case. A method for manufacturing the described aluminum electrolytic capacitor.