JP5046835B2 - Electrolytic capacitor - Google Patents

Description

  The present invention relates to an electrolytic capacitor, and more particularly to a sealing structure of an outer case that houses a capacitor element.

  An electrolytic capacitor having a wound-type capacitor element is obtained by storing a capacitor element in which an anode foil and a cathode foil are wound via a separator in a bottomed cylindrical outer case made of aluminum or hard resin. The opening of the case is sealed with a sealing body. In such an electrolytic capacitor, the anode terminal and the cathode terminal drawn out from the capacitor element have a lead boss portion into which the sealing body is inserted, and the terminal insertion hole for inserting the above lead boss portion into the sealing body Is drilled.

FIG. 6 is a schematic cross-sectional view showing the structure of a conventional sealing body, and is a view showing a state in which the sealing body 19 before sealing the opening of the outer case 18 is externally fitted to the lead boss portions 151 and 161. . In sealing the outer case 18, first, the anode terminal 150 and the lead wires 152 and 162 of the cathode terminal 160 and the lead boss portions 151 and 161 respectively joined to the anode foil and the cathode foil are connected to the terminal insertion holes 191 of the sealing body 19. The lead wire 152 or 162 is pulled out from the opening 193 through the insertion port 192. In this state, sealing is performed by curling and drawing the periphery of the opening of the outer case 18 (for example, Patent Document 1).
JP-A-7-283079

  However, in the above-mentioned conventional one, the terminal insertion hole 191 formed in the sealing body 19 is formed to have substantially the same diameter as the lead boss portions 151 and 161 formed in a substantially columnar shape. For this reason, when the lead boss portions 151 and 161 are inserted into the sealing body 19, the upper end portions of the lead boss portions 151 and 161 collide with the peripheral edge of the insertion port 192 of the terminal insertion hole 191 and are not smoothly inserted. There is a problem. Even if the lead boss portions 151 and 161 can be inserted into the insertion port 192 of the terminal insertion hole 191, the lead boss portions 151 and 161 are not completely inserted to a predetermined position of the terminal insertion hole 191 due to the inclination of the capacitor element. There is a case. In such an externally fitted state of the sealing body 19, if work vibration or unexpected external force acts on the capacitor element in which the sealing body 19 is inserted before the opening of the outer case 18 is curled and drawn, the sealing body 19. Dropout failure occurs.

  The present invention has been made to solve the above problem, and in the sealing step of sealing the opening of the exterior case, the lead boss portion prevents occurrence of defective insertion of the lead boss portion into the terminal insertion hole of the sealing body. An object of the present invention is to provide a sealing structure capable of preventing the occurrence of a drop-off failure in which the sealing body drops after the insertion of the seal.

The present invention comprises a capacitor element in which an anode foil connected to an anode terminal and a cathode foil connected to a cathode terminal are wound via a separator, and an outer case containing the capacitor element, An electrolytic capacitor in which the opening of the outer case is sealed using a sealing body in which a terminal insertion hole into which each lead boss portion of the anode terminal and the cathode terminal is inserted,
The insertion hole for the terminal of the sealing body has an insertion opening with a hole diameter larger than the diameter of each lead boss portion of the anode terminal and the cathode terminal on the capacitor element side, and a hole diameter equal to or smaller than the diameter of each lead boss portion on the opposite side to the capacitor element side. The electrolytic capacitor having the opening.
According to the above configuration, since the hole diameter of the insertion opening on the capacitor element side where the lead boss portions of the anode terminal and the cathode terminal are inserted is larger than the diameter of the lead boss portion, the lead boss portion can be smoothly inserted into the terminal insertion hole. Can do. Also, since the hole diameter of the opening on the side opposite to the capacitor element side of the terminal insertion hole is equal to or smaller than the diameter of the lead boss part, when the lead boss part is inserted into the terminal insertion hole, the lead boss part must be securely inserted to a predetermined position. The upper end portion of the lead boss portion contacts the inner surface of the terminal insertion hole. For this reason, even if there is a work vibration or an unexpected external force, the sealing body can be prevented from falling off.

  The terminal insertion hole may be formed in a tapered shape so that the hole diameter decreases linearly from the capacitor element side toward the side opposite to the capacitor element side. According to the above configuration, since the terminal insertion hole has an inclined surface, the lead boss portion can be smoothly inserted into the terminal insertion hole.

  In addition, the terminal insertion hole is formed so that a tapered portion in which the hole diameter linearly decreases from the capacitor element side toward the opposite side of the capacitor element side and a cylindrical portion having the same diameter as the hole diameter of the opening communicate with each other. It may be provided. According to the above configuration, since the tapered portion of the terminal insertion hole has an inclined surface, the lead boss portion can be smoothly inserted into the terminal insertion hole. Further, since the cylindrical portion communicating with the tapered portion has a hole diameter equal to or smaller than the diameter of the lead boss portion, the upper end portion of the lead boss portion can be brought into contact with the lower end portion of the cylindrical portion.

  The terminal insertion hole may be formed so as to have an inclined curved surface portion in which the hole diameter smoothly decreases from the capacitor element side toward the side opposite to the capacitor element side. According to the above configuration, since the terminal insertion hole has the inclined curved surface portion in which the hole diameter smoothly decreases, the lead boss portion can be smoothly inserted into the terminal insertion hole.

  The terminal insertion hole has a small-diameter portion having a diameter equal to or smaller than the diameter of the lead boss portion in the terminal insertion hole, and the small-diameter portion is positioned at least 1/2 from the capacitor element side in the thickness direction of the sealing body. It may be formed. According to the above configuration, the small diameter portion is provided at a position of 1/2 or more with respect to the thickness of the sealing body from the capacitor element side, so that the length of contact between the lead boss portion and the terminal insertion hole is short. For this reason, stress due to friction between the lead boss portion and the terminal insertion hole can be reduced. Further, since the small diameter portion has a hole diameter equal to or smaller than the diameter of the lead boss portion, the upper end portion of the lead boss portion can be brought into contact with the small diameter portion in the terminal insertion hole. For this reason, even if there is a work vibration or an unexpected external force, the sealing body can be prevented from falling off.

  According to the present invention, it is possible to prevent the occurrence of defective insertion of the lead boss portion into the terminal insertion hole of the sealing body, and it is possible to prevent the occurrence of defective sealing body dropping after the lead boss portion is inserted.

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings.
(Embodiment 1)
FIG. 1 is a schematic cross-sectional view of a capacitor element according to an embodiment of the present invention. The wound capacitor element 7 includes an anode foil 1 obtained by subjecting a foil made of a valve metal such as aluminum, tantalum, niobium, and titanium to an etching process for roughening and a chemical conversion process for forming a dielectric film. And a pair of electrode foils made of the counter cathode foil 2 are wound up via a separator 3. These are fixed by the winding tape 4 after being wound up. Lead tabs (not shown) are joined to the anode foil 1 and the counter cathode foil 2, respectively, and anodes in which lead wires 52 and 62 are attached to the lead tabs via aluminum lead boss portions 51 and 61, respectively. The terminal 5 and the cathode terminal 6 are joined.

  FIG. 2 is a schematic cross-sectional view of the electrolytic capacitor according to the embodiment of the present invention, and a capacitor element 7 having the configuration of FIG. 1 is accommodated in an aluminum outer case 8 formed in a bottomed cylindrical shape. ing. Further, the lead boss portions 51 and 61 of the anode terminal 5 and the cathode terminal 6 that are joined to the anode foil 1 and the cathode foil 2 of the capacitor element 7 and drawn from the capacitor element 7 seal the opening of the outer case 8. It is inserted into the terminal insertion hole of the sealing body 9 made of an elastic body such as rubber. As shown in FIG. 2, the periphery of the opening of the outer case 8 is bent by curling, and the peripheral surface of the outer case 8 is sealed by being drawn into an annular shape.

  FIG. 3 is a schematic cross-sectional view showing the structure of the sealing body of the present embodiment, and shows a state where the sealing body 9 before sealing the opening of the outer case 8 is externally fitted to the lead boss portions 51 and 61. FIG. As shown in the figure, the terminal insertion hole 91 of the sealing body 9 in the present embodiment has a hole diameter on the capacitor element side that is larger than the diameter of the lead boss portions 51 and 61, and is opposite to the capacitor element side. The opening 93 on the side has a hole diameter equal to or smaller than the diameter of the lead boss portions 51 and 61. Further, the terminal insertion hole 91 of the sealing body 9 is formed in a tapered shape in which the hole diameter decreases linearly from the capacitor element side toward the opposite side of the capacitor element side.

  When the sealing body 9 is attached to the capacitor element, the insertion opening 92 of the terminal insertion hole 91 formed in the sealing body 9 is faced from above the anode terminal 5 and the cathode terminal 6, and the sealing body 9 is placed in this state. By fitting into the anode terminal 5 and the cathode terminal 6, the anode terminal 5 and the cathode terminal 6 are inserted into the terminal insertion holes 91, respectively.

  At this time, since the insertion port 92 of the terminal insertion hole 91 has a larger hole diameter than the diameter of each lead boss part 51, 61, the upper end of the lead boss part 51, 61 is the peripheral edge of the insertion hole 92 of the terminal insertion hole 91. The lead wires 52 and 62 and the lead boss portions 51 and 61 are smoothly inserted into the terminal insertion holes 91. Thereby, it is possible to prevent the defective insertion of the lead boss portions 51 and 61 into the terminal insertion hole 91 of the sealing body 9. And each lead boss part 51 and 61 can be reliably inserted to the predetermined position of the insertion hole 91 for terminals.

  The diameter of the opening 93 of the terminal insertion hole 91 is set to be equal to or smaller than the diameter of the lead boss portions 51 and 61, and the upper end portions of the lead boss portions 51 and 61 are the lead boss portions 51 and 61 in the terminal insertion hole 91. In contact with the small diameter portion 94 which is equal to or less than the diameter of. For this reason, the sealing body 9 is stable and does not rattle in a state where the sealing body 9 is supported by the portions in contact with the lead boss portions 51 and 61. Accordingly, in a state in which the sealing body 9 is externally fitted to the electrode terminals 5 and 6 (a state before the curling and drawing processing is performed on the periphery of the opening of the outer case 8), work vibration and unexpected external force are applied to the outer case 8. Even in this case, the sealing body 9 can be prevented from falling off. And since the hole diameter of the opening 93 is below the diameter of the lead boss parts 51 and 61, the sealing performance of an electrolytic capacitor is not reduced.

  In the present embodiment, the hole diameter of the insertion port 92 of the terminal insertion hole 91 is not particularly limited as long as it is larger than the diameter of the lead boss portions 51 and 61, but the hole diameter is in the range of about + 20% from the diameter of the lead boss portions 51 and 61. It is preferable to set, and it is more preferable to set the pore diameter in a range up to about + 10%. If the hole diameter of the insertion port 92 is within the above range, the possibility that the upper end portions of the lead boss portions 51 and 61 collide with the periphery of the insertion port 92 when the lead boss portions 51 and 61 are inserted into the terminal insertion holes 91 is reduced. . Further, the diameter of the opening 93 of the terminal insertion hole 91 is not particularly limited as long as it is equal to or smaller than the diameter of the lead boss portions 51 and 61. However, the hole diameter is set to a range of about −20% from the diameter of the lead boss portions 51 and 61. It is preferable to set the pore diameter within a range of up to about −10%. If the hole diameter of the opening 93 is in the above range, the upper end portions of the lead boss portions 51 and 61 come into contact with the small diameter portion 94 that is equal to or smaller than the diameter of the lead boss portions 51 and 61 in the terminal insertion hole 91. 61 and the terminal insertion hole 91 are reduced in contact distance. In addition, since the terminal insertion hole 91 is formed in a tapered shape, the contact area between the lead boss portions 51 and 61 and the terminal insertion hole 91 during insertion is reduced. Therefore, friction between the lead boss portions 51 and 61 and the terminal insertion hole 91 can be reduced, and the lead boss portions 51 and 61 can be smoothly inserted.

  In the present embodiment, the hole diameter of the opening 93 may be substantially the same as the hole diameter of each of the lead boss portions 51 and 61, and the terminal insertion hole 91 may be formed in a tapered shape, but as shown in FIG. The hole diameter of the opening 93 may be smaller than the hole diameter of the lead boss portions 51 and 61, and the small diameter portion 94 having a diameter smaller than that of the lead boss portions 51 and 61 in the terminal insertion hole 91 may be provided. In this case, it is preferable that the small-diameter portion 94 is provided at a position of 1/2 or more in the thickness direction of the sealing body 9 from the capacitor element side. By using the sealing body 9 in which the terminal insertion hole 91 is formed so that the small diameter portion 94 is in the above position, the length of contact between the lead boss portions 51 and 61 and the terminal insertion hole 91 can be shortened. The stress due to friction of the lead boss portions 51 and 61 can be reduced, and the lead boss portions 51 and 61 are inserted up to half or more of the thickness of the sealing body 9, so that rattling of the sealing body 9 can be suppressed.

  In the electrolytic capacitor of the present embodiment, after mounting the sealing body 9 as described above, the periphery of the opening of the outer case 8 is sealed by curling and drawing, and the lead wires 52 and 62 are bent. Can be produced.

(Embodiment 2)
The present embodiment is the same as the first embodiment except that the structure of the sealing body is different from the structure of the sealing body shown in the first embodiment. For this reason, description is abbreviate | omitted about the same part and only a different part is demonstrated.

  FIG. 4 is a schematic cross-sectional view showing the structure of the sealing body of the present embodiment, and shows the state before sealing of the outer case as in the first embodiment. As shown in the figure, this sealing body 9 has a hole diameter of the insertion hole 92 of the terminal insertion hole 91 larger than the diameter of each lead boss part 51, 61, and a hole diameter of the opening 93 less than the diameter of each lead boss part 51, 61. A certain point is the same as in the first embodiment, but a tapered portion 91a in which the hole diameter decreases linearly from the capacitor element side toward the opposite side of the capacitor element side, and a cylindrical portion 91b having substantially the same diameter as the hole diameter of the opening 93. Are inserted in the terminal insertion hole 91.

  For this reason, the insertion opening 92 of the terminal insertion hole 91 has a larger hole diameter than the diameters of the lead boss portions 51, 61, so that the upper ends of the lead boss portions 51, 61 are the peripheral edges of the insertion opening 92 of the terminal insertion hole 91. The lead wires 52 and 62 and the lead boss portions 51 and 61 are smoothly inserted into the terminal insertion holes 91. Thereby, it is possible to prevent the defective insertion of the lead boss portions 51 and 61 into the terminal insertion hole 91 of the sealing body 9. And each lead boss part 51 and 61 can be reliably inserted to the predetermined position of the insertion hole 91 for terminals.

  Further, since the cylindrical portion 91b communicated with the tapered portion 91a has a hole diameter equal to or smaller than the diameter of the lead boss portions 51 and 61, the upper end portions of the lead boss portions 51 and 61 come into contact with the small diameter portion 94 at the lower end portion thereof. The sealing body 9 is stable in a state where it is supported at the portion in contact with the lead boss portions 51 and 61 and does not rattle. Accordingly, in a state in which the sealing body 9 is externally fitted to the electrode terminals 5 and 6 (a state before the curling and drawing processing is performed on the periphery of the opening of the outer case 8), work vibration and unexpected external force are applied to the outer case 8. Even in this case, the sealing body 9 can be prevented from falling off.

Further, according to the sealing body 9, since the upper end portions of the lead boss portions 51 and 61 are in contact with each other in the terminal insertion hole 91, the contact distance between the lead boss portions 51 and 61 and the terminal insertion hole 91 is small during insertion. Become. Furthermore, since the taper portion 91a has an inclined surface, the contact area between the lead boss portions 51 and 61 and the terminal insertion hole 91 is reduced. Therefore, friction between the lead boss portions 51 and 61 and the terminal insertion hole 91 can be reduced, and the lead boss portions 51 and 61 can be smoothly inserted. And since the hole diameter of the cylindrical part 91b is below the diameter of the lead boss parts 51 and 61, the lower end part of the cylindrical part 91b can also be utilized as a positioning part of the lead boss parts 51 and 61. Thereby, the inclination of the sealing body 9 is prevented and insertion failure can be reduced reliably.
Also in the present embodiment, the relationship between the hole diameters of the insertion port 92 and the opening 93 and the diameters of the lead boss portions 51 and 61 and the position of the small diameter portion 94 (the lower end position of the cylindrical portion 91b) are the same as in the first embodiment. It is preferable to adopt the configuration.

(Embodiment 3)
The present embodiment is the same as the first embodiment except that the structure of the sealing body is different from the structure of the sealing body shown in the first embodiment. For this reason, description is abbreviate | omitted about the same part and only a different part is demonstrated.

  FIG. 5 is a schematic cross-sectional view showing the structure of the sealing body of the present embodiment, and shows the state before sealing of the outer case as in the first embodiment. As shown in the figure, this sealing body 9 has a hole diameter of the insertion hole 92 of the terminal insertion hole 91 larger than the diameter of each lead boss part 51, 61, and a hole diameter of the opening 93 less than the diameter of each lead boss part 51, 61. Although a certain point is the same as that of Embodiment 1, the terminal insertion hole 91 having the inclined curved surface portion 91c in which the hole diameter smoothly decreases from the capacitor element side toward the opposite side to the capacitor element side is formed.

  For this reason, the insertion opening 92 of the terminal insertion hole 91 has a larger hole diameter than the diameters of the lead boss portions 51, 61, so that the upper ends of the lead boss portions 51, 61 are the peripheral edges of the insertion opening 92 of the terminal insertion hole 91. There is little worry to collide with. Further, since the terminal insertion hole 91 has the inclined curved surface portion 91c in which the hole diameter smoothly decreases, the upper end portions of the lead boss portions 51 and 61 are not easily caught by the terminal insertion hole 91 when the lead boss portions 51 and 61 are inserted. Accordingly, the lead wires 52 and 62 and the lead boss portions 51 and 61 are smoothly inserted into the terminal insertion holes 91. Thereby, it is possible to prevent the defective insertion of the lead boss portions 51 and 61 into the terminal insertion hole 91 of the sealing body 9. And each lead boss part 51 and 61 can be reliably inserted to the predetermined position of the insertion hole 91 for terminals.

The diameter of the opening 93 of the terminal insertion hole 91 is set to be equal to or smaller than the diameter of the lead boss portions 51 and 61, and the upper end portions of the lead boss portions 51 and 61 are the lead boss portions 51 and 61 in the terminal insertion hole 91. Since the sealing member 9 is in contact with the lead boss portions 51 and 61, it is stable and does not rattle. Accordingly, in a state in which the sealing body 9 is externally fitted to the electrode terminals 5 and 6 (a state before the curling and drawing processing is performed on the periphery of the opening of the outer case 8), work vibration and unexpected external force are applied to the outer case 8. Even in this case, the sealing body 9 can be prevented from falling off.
Also in the present embodiment, it is preferable that the relationship between the hole diameters of the insertion port 92 and the opening 93 and the diameters of the lead boss parts 51 and 61 and the position of the small diameter part 94 be the same as those in the first embodiment.

(Other embodiments)
(1) In the first embodiment, a sealing body having a tapered terminal insertion hole in which the hole diameter decreases linearly is used, but the terminal insertion hole has a plurality of different inclination angles. The shape which connected the taper part may be sufficient. For example, a first taper portion having a small inclination angle is provided on the capacitor element side, and a second taper portion having an inclination angle larger than the inclination angle of the first taper portion communicating with the first taper portion is provided. It may be a terminal insertion hole. By providing such tapered portions with different inclination angles, the insertion portion side taper portion has a small inclination angle so that the lead boss portion can be inserted smoothly, and each taper portion serves as a guide. Will also be smooth.
(2) In any of the above embodiments, a sealing body having one terminal insertion hole for each of the anode terminal and the cathode terminal is used, but the number of terminal insertion holes is not limited to this. For example, when a capacitor element in which a plurality of anode terminals or cathode terminals are joined is used, a sealing body having a number of terminal insertion holes corresponding to the number of the terminals can be used.
(3) In the above-described embodiment, the terminal insertion holes for the anode terminal and the cathode terminal both use sealing bodies having the same structure, but the terminal insertion holes having the structures of different embodiments are combined. May be.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further in detail, this invention is not limited to these Examples.

Example 1
A capacitor element was produced by winding an anode foil connected to the anode terminal and a cathode foil connected to the cathode terminal through a separator. Both the anode terminal and the cathode terminal were those having a lead boss portion with a diameter of 1.2 mm. The capacitor element was impregnated with a polymerization solution containing a polymerizable monomer and ferric p-toluenesulfonate and thermochemically polymerized to form a conductive polymer layer in the capacitor element.
Sealing body in which tapered terminal insertion holes shown in FIG. 3 are formed in the anode terminal and the cathode terminal of the capacitor element produced as described above (sealing body diameter: φ7.3 mm, sealing body thickness: 2 5 mm, hole diameter of the insertion port: 1.4 mm, hole diameter of the opening: 1.1 mm, position of the small diameter part: 0.8 mm from the opening side), and this is stored and fixed in an aluminum outer case, The periphery of the opening of the outer case was sealed by curling and drawing. Thereafter, the lead wire was pressed and bent to produce a solid electrolytic capacitor.

(Example 2)
As the sealing body, a sealing body having a terminal insertion hole in which the tapered portion and the cylindrical portion shown in FIG. 4 are communicated (sealing body diameter: φ7.3 mm, sealing body thickness: 2.5 mm, The same as in Example 1, except that the hole diameter: 1.4 mm, the hole diameter of the opening: 1.2 mm, the length of the cylindrical portion: 1.2 mm, and the position of the small diameter portion: 1.2 mm from the opening side) An electrolytic capacitor was manufactured.

(Example 3)
As the sealing body, a sealing body having a terminal insertion hole in which the tapered portion and the cylindrical portion shown in FIG. 4 are communicated (sealing body diameter: φ7.3 mm, sealing body thickness: 2.5 mm, The same as in Example 1 except that the hole diameter: 1.3 mm, the hole diameter of the opening: 1.1 mm, the length of the cylindrical portion: 0.5 mm, and the position of the small diameter portion: 1.2 mm from the opening side) were used. An electrolytic capacitor was manufactured.

(Comparative Example 1)
As a sealing body, a sealing body in which a terminal insertion hole having the same diameter as the insertion opening and the opening shown in FIG. 6 is formed (sealing body diameter: φ7.3 mm, sealing body thickness: 2.5 mm, insertion opening The solid electrolytic capacitor was manufactured in the same manner as in Example 1 except that the diameter of the hole was 1.2 mm and the diameter of the opening was 1.2 mm.

(Comparative Example 2)
As a sealing body, a sealing body in which a terminal insertion hole having the same diameter as the insertion opening and the opening shown in FIG. 6 is formed (sealing body diameter: φ7.3 mm, sealing body thickness: 2.5 mm, insertion opening The solid electrolytic capacitor was manufactured in the same manner as in Example 1 except that the diameter of the hole was 1.0 mm and the hole diameter of the opening was 1.0 mm. However, the lead boss portion could not be inserted into the sealing body. The outer case could not be sealed.
At the time of manufacturing 500 solid electrolytic capacitors of the above examples and comparative examples, the number of sealing members inserted and dropped were confirmed. Table 1 shows the results.

  As shown in Table 1 above, any of the solid electrolytic capacitors using the sealing bodies of the examples can prevent the occurrence of poor insertion and dropout. Therefore, the sealing step can be performed without occurrence of defective insertion or omission of the sealing body.

Schematic which shows the structure of the capacitor | condenser element which concerns on Embodiment 1 of this invention 1 is a schematic cross-sectional view of an electrolytic capacitor according to Embodiment 1 of the present invention. Schematic sectional view showing the structure of the sealing body according to Embodiment 1 of the present invention. Schematic sectional view showing the structure of the sealing body according to Embodiment 2 of the present invention. Schematic sectional view showing the structure of the sealing body according to Embodiment 3 of the present invention. Schematic sectional view showing the structure of a conventional sealing body

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Anode foil 2 Cathode foil 3 Separator 4 Winding tape 5 Anode terminal 6 Cathode terminal 7 Capacitor element 8 Exterior case 9 Sealing body 51 Lead boss part 52 Lead wire 61 Lead boss part 62 Lead wire 91 Terminal insertion hole 91a Taper part 91b Cylindrical part 91c Inclined curved surface portion 92 Insertion port 93 Opening 94 Small diameter portion

Claims (3)

A capacitor element in which an anode foil to which an anode terminal is connected and a cathode foil to which a cathode terminal is connected are wound via a separator; and an outer case housing the capacitor element, the anode terminal and the cathode An electrolytic capacitor in which an opening of the outer case is sealed using a sealing body in which a terminal insertion hole into which each lead boss portion of the terminal is inserted is provided,
The insertion hole for the terminal of the sealing body has an insertion opening with a hole diameter larger than the diameter of each lead boss portion of the anode terminal and the cathode terminal on the capacitor element side, and a hole diameter equal to or smaller than the diameter of each lead boss portion on the opposite side to the capacitor element side. possess an opening of,
The terminal insertion hole is formed in a tapered shape so that the hole diameter linearly decreases from the capacitor element side toward the opposite side of the capacitor element side,
Wherein the insertion port side of the terminal insertion holes, electrolytic capacitors that have inclined curved portion with a hole diameter toward the capacitor element side to the side opposite to the capacitor element side decreases smoothly is formed. The electrolytic capacitor according to claim 1, wherein an opening side of the terminal insertion hole is perforated so as to communicate with a cylindrical portion having a hole diameter substantially the same as the hole diameter of the opening. The terminal insertion hole has a small-diameter portion having a hole diameter equal to or smaller than the diameter of the lead boss portion in the terminal insertion hole, and the small-diameter portion is ½ or more from the capacitor element side in the thickness direction of the sealing body. electrolytic capacitor according to claim 1 or 2 is a formed position.

Images