JP2009010237A - Electrolytic capacitor, and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrolytic capacitor that is excellent in thermal resistance and capable of preventing the deterioration of the sealing property of a sealing member, and to provide a manufacturing method thereof. <P>SOLUTION: The electrolytic capacitor is provided with: a capacitor element 1 having separator paper interposed between an anode foil with a dielectric film formed and a cathode foil opposed thereto to be wound and being impregnated with an electrolyte; a bottomed cylindrical case 9 storing this capacitor element 1; and a sealing member for sealing the opening end part of this case 9. The sealing member is formed having a metal base plate 10 having a through hole and an insulating member 11 inserted into this through hole. The peripheral portion of the base plate 10 is wound up and tightened together with the opening end part of the case 9. Due to this, a force is applied from the peripheral portion to the through hole in the base plate 10. Thereby, the insulating member 11 inserted into the through hole is tightened, and the sealing property is improved. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electrolytic capacitor and a method for manufacturing the same, and more particularly to an electrolytic capacitor in which an electrolyte is impregnated in a capacitor element in which an anode foil and a cathode foil facing the electrolytic foil are wound through a separator, and a method for manufacturing the same.

  FIG. 9 is a sectional front view of a conventional electrolytic capacitor, and FIG. 10 is an exploded perspective view of a capacitor element constituting the conventional electrolytic capacitor (see, for example, Patent Document 1).

As shown in FIG. 10, the capacitor element 101 includes an anode foil 102 to which the anode lead wire 7 is attached via a lead tab terminal 106 and a cathode foil 103 to which a cathode lead wire 8 is attached via another lead tab terminal 106. Are wound in a cylindrical shape via a separator paper 104, and are wound by a winding tape 105 on the outer periphery. Then, an electrolyte is formed in such a capacitor element 101 and accommodated in a bottomed cylindrical aluminum case 109 as shown in FIG. 9, and the opening end of the case 109 is a sealing rubber as a sealing member. By sealing at 130, a conventional electrolytic capacitor is produced. The sealing rubber 130 is formed with a through hole 130a for drawing out the lead tab terminal 106 connected to the anode lead 107 and the cathode lead 108, respectively. Further, the sealing rubber 130 is fixed by subjecting the opening end of the case 109 to lateral drawing and curling.
JP-A-8-153654

  In general, it is important to maintain the sealed state in order to suppress the deterioration of the reliability of the electrolytic capacitor. However, in the conventional electrolytic capacitor having the above configuration, when left in a high temperature environment, the sealing rubber 130 as the sealing member contracts, and the interface between the sealing rubber 130 and the lead tab terminal 106 or the sealing A gap may be formed at the interface between the rubber 130 and the case 109, and moisture or the like may enter the capacitor element 101 from the outside. In addition, the sealing rubber 130 itself may be torn, moisture and the like may pass through the tear, and moisture and the like may enter the capacitor element 101. As described above, when the sealing property of the sealing rubber 130 is impaired and moisture or the like enters the capacitor element 101, the electrolyte is deteriorated, leading to a decrease in electrical characteristics such as a decrease in capacitance. Capacitor reliability deteriorates.

  This invention is made | formed in view of such a subject, The objective is to provide the electrolytic capacitor which is excellent in heat resistance, and can suppress the deterioration of the sealing performance of a sealing member, and its manufacturing method. .

  In order to achieve the above object, an electrolytic capacitor according to the present invention has a sealing member attached to an opening end portion of a metal case that houses a capacitor element connected to a metal lead wire via a lead tab terminal. In the electrolytic capacitor to be sealed, the sealing member has a base plate having at least two through holes, a lead tab terminal is inserted into the through hole, and the peripheral edge of the base plate is the opening end of the case In addition, it is characterized in that it is wound outwardly with respect to the case.

  The sealing member may further include an insulating member having two through holes, and the lead tab terminal may be inserted into the through hole of the insulating member.

Another electrolytic capacitor according to the present invention is an electrolytic capacitor in which a sealing member is mounted and sealed at an opening end of a metal case that houses a capacitor element connected to a metal lead wire via a lead tab terminal. The sealing member includes a base plate having at least two through holes and an insulating member having two through holes. An insulating member is inserted into the through hole of the base plate, and the through hole of the insulating member is inserted into the through hole of the insulating member. Is characterized in that a lead tab terminal is connected and a recess is formed around the contact portion between the insulating member and the base plate.

  The peripheral edge of the base plate is preferably wound outwardly with respect to the case together with the opening end of the case. The insulating member may be an elastic body.

  The electrolytic capacitor manufacturing method of the present invention includes a storage step of storing a capacitor element connected to a metal lead wire through a lead tab terminal in a metal case, and a lead tab terminal provided in the sealing member. In an electrolytic capacitor manufacturing method including an insertion step of inserting into a hole and a sealing step of sealing a capacitor element using a sealing member, the electrolytic capacitor includes a base plate as a sealing member, and the insertion step is based on a lead tab terminal. A base plate insertion step for inserting into the through hole of the plate, and the sealing step includes a winding step for winding the peripheral edge portion of the base plate and the opening end portion of the case in the outer direction of the case. Features.

  The sealing member may further include an insulating member, and may include an insulating member inserting step of inserting the lead tab terminal into the through hole of the insulating member before the base plate inserting step.

  ADVANTAGE OF THE INVENTION According to this invention, it is excellent in heat resistance and the electrolytic capacitor which can suppress the deterioration of the sealing performance of a sealing member, and its manufacturing method are provided.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(First embodiment)
FIG. 1 is a schematic cross-sectional view showing a configuration of an electrolytic capacitor including a sealing member according to a first embodiment of the present invention, and FIG. 2 is an exploded perspective view of a capacitor element constituting the electrolytic capacitor. FIG. 3 is a schematic plan view of a base plate constituting the sealing member, and FIG. 4 is a schematic perspective view of an insulating member constituting the sealing member. In all the drawings in FIGS. 1 to 4, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

  In the electrolytic capacitor of the first embodiment, as a capacitor element 1, as shown in FIG. 2, an anode foil 2 on which a dielectric film (not shown) is formed and a cathode foil 3 facing the anode foil 2 are interposed via separator paper 4. The one wound is used. An anode lead wire 7 is drawn out from the anode foil 2 via a lead tab terminal 6, and a cathode lead wire 8 is drawn out from the cathode foil 3 via another lead tab terminal 6. Then, as shown in FIG. 1, an electrolyte is formed in the capacitor element 1, the capacitor element 1 is stored in a bottomed cylindrical metal case 9, and a sealing member is attached to the opening end of the case 9. Wearing.

  The sealing member includes a metal base plate 10 having a through hole 10a and an insulating member 11 inserted into the through hole 10a. The sealing member is provided with a metal lead tab terminal 6 penetrating the insulating member 11 in the through hole 10a. The peripheral edge of the base plate 10 is wound around the opening end of the case 9 in the outward direction of the case 9. Further, the insulating member 11 is formed with a region 11 c that is tightened by the base plate 10 and has a recessed side wall along a contact portion with the base plate 10.

  The specific structure of the electrolytic capacitor is as follows.

The anode foil 2 is made of a foil made of a metal having a valve action such as aluminum, tantalum, or niobium, and is subjected to an etching process for roughening the foil surface and a chemical conversion process for forming a dielectric film on the foil surface. Is given. An anode lead wire 7 is connected to the upper edge of the anode foil 2 via a metal lead tab terminal 6.

  As the cathode foil 3, a foil made of a metal having the same valve action as the anode foil 2 is employed. A cathode lead wire 8 is connected to the cathode foil 3 via a metal lead tab terminal 6.

  The capacitor element 1 is configured by winding an anode foil 2 and a cathode foil 3 opposite to the anode foil 2 in a cylindrical shape via a separator paper 4 made of an insulator and the like, and winding it with an outer winding tape 5. .

  As the electrolyte, an electrolytic solution containing an inorganic acid, an organic acid or a salt thereof, or a solid electrolyte can be used. Specific examples of the solid electrolyte include manganese dioxide, TCNQ (7,7,8,8-tetracyanoquinodimethane) complex salt, conductive polymer, and the like. A conductive polymer composed of thiophene or a derivative thereof is desirable. An electrolyte selected from the above is formed in the capacitor element 1 by a known method such as impregnation or coating.

  The metal case 9 is usually an aluminum case formed in a bottomed cylindrical shape with an aluminum plate or the like that is easy to form. The capacitor element 1 is housed and fixed in the case 9, and a sealing member is attached to the opening end of the case 9 and sealed. In addition, as the metal case 9, a case made of metal such as stainless steel, copper, iron, brass or the like other than aluminum may be adopted, or a case made of these alloys may be adopted.

  The material of the base plate 10 is not particularly limited, but is preferably the same aluminum base plate as the case 9 in terms of ease of processing. In the case where the base plate 10 is made of an insulating material, the insulating member 11 is not necessarily required, but is preferably provided for improving the sealing performance as described later.

  In the base plate 10, through holes 10a are formed at predetermined positions and at predetermined intervals. Moreover, as shown in FIG. 3, it is preferable that the surface used as the inner surface side (capacitor element 1 side) of the base board 10 is formed with the recessed part 10b connected to each through-hole 10a. These recesses 10b are arranged in a cross shape around each through hole 10a, and the details will be described in the item of the manufacturing method, but are deformed and crushed in the manufacturing process. The shape of the recess 10b is a cross shape here, but the shape is provided so that a force is applied evenly from the periphery of the base plate 10 toward the center during the tightening described below, and Various applications are possible on the premise that the distance between the two through holes 10a is not substantially changed. For example, as the concave portion 10b, not only a concave shape that connects the through hole 10a and the periphery of the base plate 10 with a straight line as shown in FIG. 8A, but also a curved shape as shown in FIGS. 8B and 8C. Alternatively, the shape may include a concentric recess.

  Moreover, the number of the through-holes 10a of the base plate 10 should just be two or more, and the number and diameter are not specifically limited. For example, in addition to the two through holes 10a into which the lead tab terminals 6 are inserted, some through holes 10a are provided, a potch is formed in the through hole 10a, and a self-standing shape is provided without a seat plate. Good.

The peripheral edge portion of the base plate 10 is tightened together with the opening end portion of the case 9 to form a winding tightening portion 12 as shown in FIG. 1, and the opening end portion of the case 9 is sealed. When the insulating member 11 is provided, as the diameter of the through hole 10a is reduced, the insulating member 11 forms a recessed region 11c as shown in FIG. Thereby, the sealing performance of the capacitor element 1 is improved as compared with the case without the insulating member 11. Further, at the time of this tightening, a lateral restriction is applied to the vicinity of the opening end of the case 9 so that the opening of the case 9 becomes narrow in the inner diameter direction, and the diameter of the through hole 10a is reduced by the tightening. It is strengthening. The recess 10b of the base plate 10 may be formed on the outer surface side, or may be formed on both the inner surface side and the outer surface side.

  The insulating member 11 includes an elastic body, in particular, silicon rubber (SR), fluorine rubber (FR), ethylene propylene rubber (EPT), high pylon rubber (CSM), which are materials having relatively high heat resistance and sealing properties. Insulating rubbers such as butyl rubber (IIR) and isoprene rubber (IR) are used. As shown in FIG. 4, the insulating member 11 has a predetermined protruding portion (a protruding portion having a through hole 11a for inserting the lead tab terminal 6) 11b at a position (two locations) corresponding to the through hole 10a of the base plate 10. Is formed in a state provided. The lead tab terminal 6 is inserted into each through hole 11a of the insulating member 11, and the protruding portion 11b of the insulating member 11 is inserted into the through hole 10a of the base plate 10 from the inner surface side (capacitor element 1 side). . As shown in FIG. 1, the insulating member 11 is formed with a region 11 c that is tightened by the base plate 10 and has a side wall that is recessed in an annular shape along the contact portion with the base plate 10. The insulating member 11 attached to the base plate 10 is installed so as to cover the entire surface that becomes the inner surface side (capacitor element 1 side) of the base plate 10.

  The capacitor element 1 is a “capacitor element” of the present invention, the lead tab terminal 6 is a “lead tab terminal” of the present invention, the anode lead wire 7 and the cathode lead wire 8 are “metal lead wires” of the present invention, and the case 9 is The “case” of the present invention, the sealing member is the “sealing member” of the present invention, the base plate 10 is the “base plate” of the present invention, the through hole 10 a is the “through hole of the base plate” of the present invention, and the insulating member 11 is the main plate. The “insulating member” of the invention, the through hole 11a is an example of the “through hole of the insulating member” of the present invention, and the recessed region 11c is an example of the “recessed portion” of the present invention.

(Production method)
Next, a method for manufacturing the electrolytic capacitor according to the first embodiment of the present invention shown in FIG. 1 will be described.

  (Step 1) A foil made of a valve metal that has been subjected to an etching process for roughening and a chemical conversion process for forming a dielectric film is used as an anode foil 2, and a cathode foil 3 facing the anode foil 2 is used as a separator. Capacitor element 1 wound into a cylindrical shape via paper 4 is formed (element forming step: step 1). Anode lead wire 7 and cathode lead wire 8 are attached to anode foil 2 and cathode foil 3 via lead tab terminals 6, respectively. The capacitor element 1 is subjected to cut formation and heat treatment in order to form a dielectric film on the end face of the anode foil 2 and to re-form the dielectric film peeled off when the anode foil 2 is wound. 2 is strengthened.

  (Step 2) A chemical polymerization liquid in which a monomer that becomes a conductive polymer and an oxidizing agent are mixed is prepared. And after immersing the capacitor | condenser element 1 in this chemical polymerization liquid, a conductive polymer layer is formed as an electrolyte inside the capacitor | condenser element 1 by heat-processing (element formation process: step 2).

(Step 3) An aluminum base plate 10 having a through hole 10a is prepared. In the through hole 10a, as shown in FIG. 5, a concave portion 10b connected to each through hole 10a is formed on the surface which is the inner surface side (capacitor element 1 side) of the base plate 10. These recesses 10b are arranged in a cross shape around each through hole 10a. Next, as shown in FIG. 4, a predetermined protrusion (protrusion having a through hole 11a for inserting the lead tab terminal 6) 11b is provided at a position corresponding to the through hole 10a of the base plate 10. Insulating member 11 is prepared. And the lead tab terminal 6 is inserted from the direction of the surface which becomes the capacitor | condenser element 1 side with respect to the through-hole 11a of this insulating member 11 (insulating member insertion process of a sealing process). Thereafter, the protruding portion 11b of the insulating member 11 into which the lead tab terminal 6 is inserted is inserted into the through hole 10a of the base plate 10 (base plate insertion step of the sealing step). In this way, the sealing member of the present invention is attached to the capacitor element 1.

  (Step 4) An aluminum case 9 formed in a bottomed cylindrical shape is prepared. Then, the capacitor element 1 is housed and fixed in the case 9 (housing process).

  (Step 5) The base plate 10 is disposed at the opening end of the case 9, and the base plate 10 is placed in a lateral direction with respect to the vicinity of the opening end of the case 9 so that the opening of the case 9 narrows in the inner diameter direction. The peripheral edge portion and the opening end portion of the case 9 are tightened (the tightening step of the sealing step). Thereby, the tightening part 12 is formed. At this time, the metal base plate 10 contracts due to physical stress during horizontal drawing and tightening, and the recess 10b is deformed and crushed. Therefore, the base plate 10 is in the state shown in FIG. 3 from the state shown in FIG. To change. Accordingly, the diameter of the through hole 10a of the base plate 10 is reduced, and the insulating member 11 inserted into the through hole 10a is tightened. By this tightening, the insulating member 11 is formed with a region 11c in which the side wall is annularly recessed along the contact portion with the base plate 10. In this way, the capacitor element 1 is sealed in the case 9 by the sealing member.

  Through the above steps, an electrolytic capacitor including the sealing member according to the first embodiment is manufactured.

(Second Embodiment)
FIG. 6 is a schematic cross-sectional view showing a configuration of an electrolytic capacitor including a sealing member according to a second embodiment of the present invention. FIG. 7 is a schematic perspective view of an insulating member constituting the sealing member. The difference from the first embodiment is that the insulating members 21 constituting the sealing member are provided corresponding to the through holes 10a of the base plate 10, respectively. The rest is the same as in the first embodiment.

  In the electrolytic capacitor according to the second embodiment, as shown in FIG. 6, the sealing member includes a metal base plate 10 having through holes 10a at two locations, and an insulating member 21 inserted corresponding to each through hole 10a. And a metal lead tab terminal 6 inserted through the insulating member 21 for each through-hole 10a. Then, the peripheral edge of the base plate 10 is wound around the opening end of the case 9 to form a tightened portion 12, and each insulating member 21 is tightened by the base plate 10 to be in contact with the base plate 10. A region 21c in which the side wall is recessed in an annular shape is formed.

  Specifically, the insulating member 21 is made of the same insulating rubber as that of the previous insulating member 11. As shown in FIG. 7, the insulating member 21 is formed in a state in which a protruding portion (a protruding portion having a through hole 21 a for inserting the lead tab terminal 6) 21 b inserted into the through hole 10 a of the base plate 10 is provided. Has been. The lead tab terminal 6 is inserted into the through hole 21a of each insulating member 21, and the protruding portion 21b of the insulating member 21 is inserted into the through hole 10a of the base plate 10 from the capacitor element 1 side. In addition, each insulating member 21 is formed with a region 21 c that is tightened by the base plate 10 and has a side wall that is recessed in an annular shape along a contact portion with the base plate 10. In the second embodiment, the insulating member 21 is formed by partially covering the capacitor element 1 side of the base plate 10. The insulating member 21 is an example of the “insulating member” of the present invention, the through hole 21a is an example of the “through hole of the insulating member” of the present invention, and the recessed region 21c is an example of the “recessed portion” of the present invention.

  Moreover, the electrolytic capacitor provided with such a sealing member according to the second embodiment employs the insulating member 21 that constitutes the sealing member, and thus undergoes the same manufacturing method (step 1 to step 5) as that of the first embodiment. It can be manufactured easily.

  In the following examples, an electrolytic capacitor corresponding to the above-described embodiment was produced, and the characteristics were evaluated. Moreover, in the comparative example, the electrolytic capacitor provided with the conventional sealing member was produced, and the characteristic evaluation was performed.

Example 1
In Example 1, as an electrolytic capacitor corresponding to the first embodiment, an electrolytic capacitor A was produced through the above-described steps (Step 1 to Step 5).

  (Step 1A) An aluminum foil subjected to an etching process for roughening and a chemical conversion process (applied voltage 5 V) for forming a dielectric film is used as an anode foil 2, and a cathode foil 3 facing the anode foil 2 is used. The capacitor element 1 is formed by winding it in a cylindrical shape via the separator paper 4. Anode lead wire 7 and cathode lead wire 8 are attached to anode foil 2 and cathode foil 3 via lead tab terminals 6, respectively. Thereafter, the capacitor element 1 is subjected to a cut formation process and a heat treatment at 260 ° C.

  (Step 2A) A chemical polymerization solution is prepared by mixing a suitable amount of 3,4-ethylenedioxythiophene monomer and p-toluenesulfonic acid ferric butyl alcohol as an oxidizing agent. And after immersing the capacitor | condenser element 1 in this chemical polymerization liquid, it heat-processes at a temperature slightly higher than 100 degreeC, and the electroconductivity high which consists of 3, 4- ethylene dioxythiophene between the bipolar electrode foils of the capacitor | condenser element 1 is carried out. A molecular layer is formed as an electrolyte.

  (Step 3A) An aluminum base plate 10 having a thickness of about 200 μm and a purity of 99.0% is prepared as the base plate shown in the previous step 3. Here, in the base plate 10, through holes 10 a are formed at two predetermined locations, and a recess (width: several) connected to each through hole 10 a on the inner surface side (capacitor element 1 side) of the base plate 10. 10b is formed in a cross-shaped shape (depth: approximately half to 2/3 of the plate thickness). Furthermore, an insulating member 11 made of butyl rubber is provided, which is provided with a predetermined protrusion (protrusion having a through hole 11a for inserting the lead tab terminal 6) 11b at a position corresponding to the through hole 10a of the base plate 10. And the protrusion part 11b of this insulation member 11 is inserted in the through-hole 10a of the base board 10 from the direction of the surface used as an inner surface side (capacitor element 1 side). Thereafter, the lead tab terminal 6 is inserted into the through hole 11a of the insulating member 11 from the same direction. Thereby, the sealing member of the present invention is attached to the capacitor element 1.

  (Step 4A) As the bottomed cylindrical case described in the previous step 4, a case 9 made of aluminum having a thickness of about 300 μm and a purity of 99.0% is prepared. The capacitor element 1 is housed and fixed in the case 9.

  (Step 5A) The base plate 10 is arranged at the opening end of the case 9, and the base plate 10 is moved while being laterally narrowed near the opening end of the case 9 so that the opening of the case 9 is narrowed in the inner diameter direction. The peripheral edge and the open end of the case 9 are double-tightened. Thus, the tightening portion 12 is formed, and the region 11 c in which the side wall of the insulating member 11 is recessed along the contact portion with the base plate 10 is formed. In this way, the capacitor element 1 is sealed in the case 9 by the sealing member of the present invention.

  As described above, the electrolytic capacitor A in Example 1 is manufactured.

(Example 2)
In Example 2, as an electrolytic capacitor corresponding to the second embodiment, Example 1 except that an individual insulating member 21 is employed for the through hole 10a instead of the integral insulating member 11 in the step 3A. An electrolytic capacitor B was produced under the same conditions and method as in Example 1.

(Comparative example)
In the comparative example, the conventional sealing rubber 130 shown in FIG. 8 was adopted as the sealing member, and the sealing was carried out except that the opening end of the case 9 was sealed and fixed by performing lateral drawing and curling. An electrolytic capacitor X was produced under the same conditions and method as in Example 1.

(Evaluation)
Each electrolytic capacitor was evaluated for capacitance (C) and equivalent series resistance (ESR). The capacitance was measured by applying an AC rated voltage of 120 Hz to each electrolytic capacitor, and the equivalent series resistance was measured by applying an AC rated voltage of 100 kHz to each electrolytic capacitor. Each evaluation was performed after 3000 hours had passed in an initial state (before the high temperature load test) and in a thermostatic bath in which the electrolytic capacitor was held at 150 ° C. as a high temperature load test.

  Table 1 shows the evaluation results of capacitance and equivalent series resistance. Each characteristic value is an average of 30 samples.

  The capacitance change rate and the equivalent series resistance change rate are calculated by the following formulas (1) and (2) using respective characteristic values before and after the high temperature load test.

Capacitance change rate (%) = (capacitance difference ΔC before and after high temperature load test / capacitance C before high temperature load test) × 100 (1)
Equivalent series resistance change rate (times) = (Equivalent series resistance after high-temperature load test / Equivalent series resistance before high-temperature load test) (2)

  As shown in Table 1, in Example 1 (Electrolytic Capacitor A) and Example 2 (Electrolytic Capacitor B), compared to the conventional example (Electrolytic Capacitor X), the capacitance and equivalent series resistance of the high temperature load test are higher. Change (deterioration) is suppressed to a small level. This is presumably because the sealing structure of the present invention prevents deterioration of the sealing performance of the electrolytic capacitor and prevents moisture and the like from entering the capacitor element.

  Further, in Example 1 (Electrolytic Capacitor A), compared with Example 2 (Electrolytic Capacitor B), the deterioration of the capacitance due to the high temperature load test is further suppressed. This is because the entire surface of the sealing member on the capacitor element side of the base plate is covered with an insulating member, which makes it difficult for the base plate to deform due to a thermal load during a high temperature load test, and between the base plate and the insulating member. This is presumed to be because the deterioration of the adhesiveness in the case was suppressed.

  According to the electrolytic capacitor and the manufacturing method of the above-described embodiment, the following effects can be obtained.

  (1) According to the sealing structure of the electrolytic capacitor according to the present embodiment, the proportion of the insulating member in the sealing member is reduced as compared with the conventional sealing structure using only the insulating member (sealing rubber). Permeation of moisture and the like from the atmosphere due to deterioration and shrinkage and penetration of moisture and the like from the contact portion between the insulating member and the case are reduced, and deterioration of the sealing performance of the electrolytic capacitor can be suppressed.

  (2) Between the base plate 10 and the insulating member 11 (insulating member 21) by the recessed region 11 c (the recessed region 21 c) that is tightened by the base plate 10 and formed along the contact portion with the base plate 10. This makes it difficult to cause a positional shift at the base plate 10 and improves the adhesion between the base plate 10 and the insulating member 11 (insulating member 21). For this reason, the sealing performance of the sealing member is improved, and the deterioration of the reliability of the electrolytic capacitor due to the thermal load can be suppressed.

  (3) By joining the metal base plate 10 of the sealing member and the case 9 with a tightening structure (winding portion 12), compared to a conventional sealing structure with only an insulating member (sealing rubber), Intrusion of moisture or the like from the contact portion between the insulating member 11 (insulating member 21) and the case 9 is reduced, and deterioration of the sealing performance of the electrolytic capacitor can be suppressed.

  (4) In the electrolytic capacitor according to the present embodiment, gas may be generated due to the electrolytic solution impregnated in the capacitor element 1 due to a thermal load and the internal pressure may increase. The effect of suppressing the stoppage deterioration can be enjoyed more effectively.

  (5) By further covering the surface on the capacitor element 1 side of the base plate 10 of the sealing member with the insulating member 11 (insulating member 21), the internal pressure is increased by the gas generated from the capacitor element 1 due to the thermal load, and the internal pressure As a result, the insulating member 11 (insulating member 21) is prevented from jumping out of the through hole 10a of the base plate 10. As a result, the heat resistance reliability of the electrolytic capacitor can be improved.

  (6) As in the first embodiment (for example, Example 1), by covering the entire surface of the sealing member on the capacitor element 1 side of the base plate 10 with the insulating member 11, the strength of the sealing member is increased. When a thermal load is applied, the gas generated from the capacitor element 1 prevents the internal pressure from increasing and the base plate 10 from being deformed. Moreover, it is also suppressed that the base plate 10 repeats expansion and contraction due to intermittent heat load in the use environment. For this reason, the fall of the adhesiveness between the base board 10 and the insulating member 11 is suppressed, and the sealing performance deterioration of an electrolytic capacitor can further be suppressed.

  (7) According to the manufacturing method of this embodiment, a suitable electrolytic capacitor as described in the above (1) to (6) can be manufactured.

  (8) According to the manufacturing method of the present embodiment, the periphery of the base plate 10 and the open end of the case 9 are tightened to reduce the diameter of the through-hole 10a and seal it. The insulating member 11 (insulating member 21) inserted into the through hole 10a by the base plate 10 is tightened, and between the base plate 10 and the insulating member 11 (insulating member 21) or between the insulating member 11 (insulating member 21) and Adhesion between the lead tab terminals 6 can be improved. For this reason, the electrolytic capacitor by which the sealing performance deterioration of the sealing member was suppressed can be provided.

  (9) Since the peripheral edge portion of the base plate 10 and the opening end portion of the case 9 are sealed by tightening, at least as compared with the case of sealing using only a conventional insulating member (sealing rubber). It is possible to manufacture an electrolytic capacitor in which the adhesion between the case 9 and the sealing member is improved and the sealing property deterioration is further suppressed.

(10) Since the peripheral edge of the base plate 10 and the opening end of the case 9 are sealed by tightening, it is necessary to consider the combination of bonding materials compared to the case of sealing using a conventional welding method. Therefore, it is possible to manufacture an electrolytic capacitor in which the sealing property deterioration is suppressed at a low cost.

  (11) In the electrolytic capacitor of the present embodiment, gas may be generated due to the electrolyte impregnated in the capacitor element 1 by a thermal load and the internal pressure may increase. An electrolytic capacitor that can more effectively enjoy the effect of suppressing deterioration can be manufactured.

  (12) According to the manufacturing method of the present embodiment, the diameter of the through hole 10a connected to the recess 10b of the base plate 10 is reduced due to physical stress at the time of winding performed while deforming the recess 10b of the base plate 10. The insulating member 11 (insulating member 21) inserted into the through hole 10a is tightened by the base plate 10. As a result, the adhesion between the base plate 10 and the insulating member 11 (insulating member 21) and between the insulating member 11 (insulating member 21) and the lead tab terminal 6 is improved, so that the sealing performance of the sealing member is deteriorated. It is possible to provide an electrolytic capacitor in which is suppressed.

  (13) By providing the base plate 10 with the recess 10b connected to the through hole 10a, the through hole 10a can be reduced with higher control when tightening. For this reason, the electrolytic capacitor in which the sealing property deterioration is suppressed can be stably manufactured.

  (14) The metal base plate 10 is more reliably contracted by the horizontal drawing and the physical stress at the time of winding by forming the winding structure (winding portion 12) by tightening while performing the horizontal drawing. Can do. As a result, the effects (7) to (13) can be enjoyed more reliably, and the electrolytic capacitor in which the sealing member deterioration of the sealing member is suppressed can be stably manufactured.

  The present invention is not limited to the above-described embodiment, and various modifications such as design changes can be added based on the knowledge of those skilled in the art, and the embodiment to which such a modification is added. Can also be included in the scope of the present invention.

  In the said 1st Embodiment, although the example which coat | covered the whole surface which becomes the capacitor | condenser element side of the base plate in a sealing member with the insulating member was shown, this invention is not limited to this. For example, an insulating member may be further provided in contact with the case, and the insulating member may be fixed by applying a lateral diaphragm to the side surface of the case in contact with the insulating member. By doing in this way, since the sealing performance is improved by the insulating member, deterioration of the sealing performance of the electrolytic capacitor due to a thermal load can be suppressed while the sealing performance of the entire electrolytic capacitor is improved.

  In the said embodiment, although the example which employ | adopted the insulating rubber which has a protrusion part as an insulating member was shown, this invention is not limited to this. For example, a cylindrical insulating rubber such as a tube may be employed. In this case, effects other than the above (5) and (6) can be enjoyed.

  In the above embodiment, if necessary, after sealing with a sealing member, a plastic seat plate may be attached to the top of the electrolytic capacitor, and press working and bending may be performed using the anode lead wire and the cathode lead wire as electrode terminals. . Even in such a case, the above-mentioned effect can be enjoyed.

  In the said embodiment, although the recessed part provided in a base board showed the example arrange | positioned in cross shape centering on each through-hole, this invention is not limited to this. The concave portion provided in a cross shape is simple and effective for reducing the overall size of the through hole. However, as shown in FIG. 8, the concave portion is configured to reduce the through hole during lateral drawing and tightening. It only has to be arranged.

1 is a schematic cross-sectional view showing a configuration of an electrolytic capacitor according to a first embodiment of the present invention. The exploded perspective view of the capacitor element which constitutes the electrolytic capacitor concerning a 1st embodiment of the present invention. The schematic plan view of the base board which comprises the sealing member of 1st Embodiment. The schematic perspective view of the insulating member which comprises the sealing member of 1st Embodiment. The schematic plan view in the manufacture process of the base board which comprises the sealing member of 1st Embodiment. The schematic sectional drawing which shows the structure of the electrolytic capacitor which concerns on 2nd Embodiment of this invention. The schematic perspective view of the insulating member which comprises the sealing member of 1st Embodiment. (A)-(C) The figure which shows the example of a shape of the recessed part of the base board of this invention. The schematic sectional drawing which shows the structure of the conventional electrolytic capacitor. The disassembled perspective view of the capacitor | condenser element which comprises the conventional electrolytic capacitor.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Capacitor element, 2 Anode foil, 3 Cathode foil, 4 Separator paper, 5 Winding tape, 6 Lead tab terminal, 7 Anode lead wire, 8 Cathode lead wire, 9 Case, 10 Base plate, 10a Through hole, 10b Recessed part, 11 Insulating member, 11a through-hole, 11b protruding portion, 11c recessed area, 12 tightening portion.

Claims (8)

In an electrolytic capacitor that attaches and seals a sealing member to an opening end of a metal case that houses a capacitor element connected to a metal lead wire via a lead tab terminal,
The sealing member has a base plate having at least two through holes,
The lead tab terminal is inserted into the through hole,
The electrolytic capacitor according to claim 1, wherein a peripheral edge portion of the base plate is wound outwardly with respect to the case together with an opening end portion of the case.   The electrolytic capacitor according to claim 1, further comprising an insulating member having two through holes as the sealing member, wherein the lead tab terminal is inserted into the through hole of the insulating member. In an electrolytic capacitor that attaches and seals a sealing member to an opening end of a metal case that houses a capacitor element connected to a metal lead wire via a lead tab terminal,
The sealing member has a base plate having at least two through holes and an insulating member having two through holes,
The insulating member is inserted into the through hole of the base plate, the lead tab terminal is inserted into the through hole of the insulating member,
An electrolytic capacitor, wherein a recessed portion is formed around a contact portion between the insulating member and the base plate.   The electrolytic capacitor according to claim 3, wherein the peripheral edge portion of the base plate is wound outwardly with respect to the case together with the opening end portion of the case.   The electrolytic capacitor according to claim 1, wherein the insulating member is an elastic body.   The electrolytic capacitor according to claim 1, wherein the base plate is provided with a recess. A storage step of storing a capacitor element connected to a metal lead wire via a lead tab terminal in a metal case, an insertion step of inserting the lead tab terminal into a through hole provided in a sealing member, In a method for producing an electrolytic capacitor comprising a sealing step of sealing a capacitor element using a sealing member,
As the sealing member, it has a base plate,
The insertion step includes a base plate insertion step of inserting the lead tab terminal into the through hole of the base plate,
The method of manufacturing an electrolytic capacitor according to claim 1, wherein the sealing step includes a winding step of winding a peripheral portion of the base plate and an opening end portion of the case in an outer direction of the case. As the sealing member, further having an insulating member,
The method for manufacturing an electrolytic capacitor according to claim 7, further comprising an insulating member inserting step of inserting the lead tab terminal into the through hole of the insulating member before the base plate inserting step.

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