JP6047971B2 - Capacitor manufacturing method - Google Patents

Description

The present invention is an electric double layer capacitor, relates capacitors such as electrolytic capacitor, a method of manufacturing a capacitor, for example using a cold connection (cold weld) method to connect to the lead-out terminals and the electrode foil of the capacitor element.

  In capacitor elements used in capacitors such as electrolytic capacitors and electric double layer capacitors, a separator is placed between the anode and cathode electrode foils and wound to impregnate the electrolyte, or the electrode foils and separators are alternated. And impregnated with an electrolytic solution. The electrode foil on the anode side is subjected to a chemical conversion treatment on the foil that has undergone the etching treatment to form a dielectric oxide film. For the cathode side electrode foil, for example, an etched foil is used. A lead terminal is connected to any electrode foil, and for example, cold welding is used for connecting the lead terminal and the electrode foil. Cold pressure welding is a method of pressure welding the stacked members in a non-heated state.

In the connection by the cold welding method, it is known to use a die having a trapezoidal pressing surface as a die that presses against a connection portion between an electrode foil and a lead terminal (for example, Patent Document 1 and Patent Document 2). .

JP 7-235453 A JP 2007-273645 A

  By the way, in the connection between the extraction terminal and the electrode foil using the cold pressure welding, the electrode foil is placed on the extraction terminal installed on the flat mold, and the pressure welding mold is pressed from the electrode foil. The electrode foil is sandwiched between the pressure contact mold and the lead terminal. Due to the pressing of the press-contacting die, a joint portion of the electrode foil and the lead terminal is generated by the tip end portion of the press-contacting die.

  Due to the pressing of the press contact mold, the electrode foil and the lead terminal are deformed according to the tip shape of the press contact mold. The lead terminal exhibits a metal flow in the width direction around the above-described joint and causes elongation. Following this elongation, the electrode foil is elongated in the radial direction. Thus, in the part where elongation has occurred, there is a problem that the connection between the electrode foil and the lead terminal becomes incomplete.

  On the other hand, the electrode foil and the lead terminal are fixed at the joint. Thinning occurs in the electrode foil extending around the joint. The electrode foil is thinner than the lead terminal, and thinning due to elongation weakens the electrode foil, and there is a problem that the connection strength between the lead terminal and the electrode foil is lowered.

Therefore, in view of the above problems, an object of the present invention is to suppress the elongation of the lead terminal due to pressurization and prevent the electrode foil from being elongated and weakened.

In order to achieve the above object, the capacitor manufacturing method of the present invention allows at least the side surface of the extraction terminal connected to the electrode foil to allow deformation of the extraction terminal between the side surface and a desired allowable deformation amount. A step of installing a restraining jig having a space for preventing the above deformation, a step of overlapping the extraction terminal and the electrode foil, pressing a press-contact mold from the top of the electrode foil, and A step of allowing the deformation to the space portion and connecting the lead terminal and the electrode foil.

In the method for manufacturing the above Kiko capacitor, the constraining jig is provided with protrusions single or multiple in surface contact with the lead terminal, placing said lead terminal to the surface, the electrode on the lead terminal A step of stacking the foils and a step of pressing the pressure contact mold from above the electrode foil to connect the lead terminal and the electrode foil may be included.

In the method for manufacturing the above Kiko capacitor, a step of superimposing comprises a single or a plurality of projections on surface portions in contact with the lead terminal, placing said lead terminal to the surface, the electrode foil to the lead terminal, recesses by the pressure die to the lead terminals against the press mold prior Symbol lead-out terminals, and may be formed concave by the convex portions of the restraining jig.

In the method for manufacturing a capacitor, the convex portion of the restraining jig may be formed at an end portion in the axial direction of the lead terminal.

  According to the present invention, the following effects can be obtained.

  (1) The extension of the lead terminal is suppressed, and the extension of the electrode foil can be prevented.

  (2) The weakening of the electrode foil due to elongation can be prevented, and the connection strength with the lead terminal can be increased.

  (3) A highly reliable capacitor can be manufactured by preventing elongation and weakening of the electrode foil and increasing the connection strength with the lead terminal.

Other objects, features, and advantages of the present invention will become clearer with reference to the accompanying drawings and each embodiment.

It is a figure which shows an example of the extraction terminal and restraint jig which concern on 1st Embodiment. It is a figure which shows the connection of an extraction terminal and electrode foil. It is a figure which shows the connection of the extraction terminal and electrode foil which concern on 2nd Embodiment. It is a perspective view which shows the modification of a restraining jig | tool. It is sectional drawing which shows an example of the preforming of the extraction terminal which concerns on 3rd Embodiment, and the connection of an extraction terminal and electrode foil. It is sectional drawing which shows an example of the preforming of the extraction terminal which concerns on 4th Embodiment, and the connection of an extraction terminal and electrode foil. It is sectional drawing which shows an example of the preforming of the extraction terminal which concerns on 5th Embodiment, and the connection of an extraction terminal and electrode foil.

[First Embodiment]

  1A and 1B show a lead terminal and a restraining jig according to the first embodiment. FIG. 1B shows a cross section taken along line IB-IB in FIG.

  The lead terminal 2 is connected to the electrode foil 4 (B in FIG. 2) of the capacitor element. The lead terminal 2 is provided with a flat portion 2-1 that is press-connected to the electrode foil 4. A main body portion 2-2 and a lead portion 2-3 are provided in the axial direction of the flat portion 2-1. The flat part 2-1 and the main body part 2-2 are made of the same metal material as the electrode foil 4. The lead portion 2-3 is a solderable metal material and is thinner than the main body portion 2-2 and connected to the main body portion 2-2 by welding.

  The flat part 2-1 is, for example, a flat rectangular parallelepiped shape having a width W1, a length L1, and a thickness D1. The flat part 2-1 is arranged on the restraining jig 6 as shown in FIG. 1B when connecting to the electrode foil 4.

The restraining jig 6 includes a flat bottom 6-1 and a U-shaped side wall 6-2. A cavity 8 is formed by the bottom portion 6-1 and the side wall portion 6-2. The cavity 8 is open on the upper surface side, and has an opening 6-3 for inserting the flat portion 2-1 of the lead terminal 2. The cavity 8 has a width W2, a length L2, and a depth D2 with respect to the flat part 2-1. For example, the width W2, the length L2, the depth D2 and the width W1, the length L1, and the thickness D1 are as follows.
W2> W1, L2> L1, D2 ≠ D1

  The widths W1 and W2 and the lengths L1 and L2 have a relationship of W2−W1 = ΔW and L2−L1 = ΔL. For example, ΔW / 2 and ΔL are set to ΔW / 2 = ΔL (that is, ΔW = 2 × ΔL). As shown in FIG. 1A, when the edge portion of the main body portion 2-2 of the flat portion 2-1 is disposed in the vicinity of the opening edge portion of the opening portion 6-3 of the restraining jig 6, the flat wall and the inner wall of the cavity 8 are flattened. A space portion 10 having a width ΔW / 2 (= ΔL) allowing deformation of the lead terminal 2 is set between the portion 2-1 and the portion 2-1. This space portion 10 constitutes an allowable width for the extension of the flat portion 2-1. In the figure, the arrow indicates the extending direction of the flat part 2-1. Moreover, the broken line has shown the press-contact connection part 12 with the electrode foil 4. FIG.

<Manufacturing process>

  2A and 2B show an example of a manufacturing process of a capacitor. This manufacturing process is an example of a method for manufacturing a capacitor of the present invention.

  As shown in FIG. 2A, the flat part 2-1 of the lead terminal 2 is installed in the cavity 8 of the restraining jig 6. The flat portion 2-1 is covered with the electrode foil 4, and the electrode foil 4 is arranged in a direction orthogonal to the flat portion 2-1. The electrode foil 4 is provided with a treatment layer 4-2 such as an etching layer or a dielectric oxide film on the surface of a bare metal portion 4-1 such as aluminum.

  As shown to B of FIG. 2, a pair of press-contact metal mold | die 14 arrange | positioned on the upper surface of the electrode foil 4 is pressed on the electrode foil 4 and the flat part 2-1, and both press-contact connection is performed. A spherical portion 16 is formed at the tip of the press-contacting die 14, and a conical portion 20 is formed between the spherical portion 16 and the columnar portion 18.

  When such a press-contacting die 14 is pressed against the electrode foil 4 and the flat part 2-1, as shown in FIG. 2C, the electrode foil 4 and the flat part 2-1 are formed by the cold press-contacting method. Connected in the cavity 8. By this connection, the flat portion 2-1 is formed by causing a metal flow in the width direction.

  In this embodiment, a space portion 10 is formed between the side wall portion 6-2 and the flat portion 2-1 of the restraining jig 6. For this reason, the pressed flat part 2-1 spreads to the space part 10 side, and a metal flow is produced. Due to the metal flow in the vertical and horizontal directions to the space portion 10 as described above, the flat portion 2-1 is prevented from extending only in the longitudinal direction. As a result, the connection strength between the lead terminal 2 and the electrode foil 4 is increased.

  In this way, by providing the space portion 10 that allows extension to the inner surface of the flat portion 2-1 of the lead terminal 2, the deformation amount of the flat portion 2-1 due to metal flow is made uniform, and the flat portion 2-1 The elongation (deformation) is not biased only in the direction toward the main body 2-2. Since the deformation of the flat part 2-1 toward the side surface part is restrained by the side wall part 6-2 of the restraining jig 6, the deformation exceeding the allowable deformation amount is prevented. Moreover, the deformation | transformation to the main-body-part 2-2 direction of the flat part 2-1 is reduced by extension to this flat part 2-1. Thereby, when the restraining jig 6 is used, the crack of the electrode foil 4 due to the extension or deformation of the lead terminal 2 to the main body part 2-2 or the lead part 2-3 can be suppressed.

[Second Embodiment]

  FIG. 3A shows the lead terminal 2 according to the second embodiment. B of FIG. 3 shows a molded state of the extraction terminal 2 from which the electrode foil 4 is omitted.

  In the flat part 2-1 of the lead terminal 2, as shown in A of FIG. 3, a circular through part 22 is formed avoiding the pressing position of the press contact mold 14. The electrode foil 4 is overlapped on the flat part 2-1 having such a through part 22, and the above-described press contact mold 14 is pressed to perform press contact connection.

  At the time of press-contact of the press-contacting die 14, metal elongation (metal flow) generated in the flat portion 2-1 occurs on the space side of the through-hole 22. That is, the penetrating portion 22 functions as a metal flow escape portion.

  In this way, by providing the inner surface portion of the flat portion 2-1 of the lead terminal 2 with a portion that allows elongation, elongation (deformation) toward the main body portion 2-2 is reduced. Thereby, when the restraining jig 6 is used, the extension and deformation of the lead terminal 2 to the main body part 2-2 and the lead part 2-3 are reduced, and cracking of the electrode foil 4 can be suppressed.

  If the restraining jig 6 is used, the metal flow to the side surface side of the extraction terminal 2 can be restricted, and the extension and deformation of the extraction terminal 2 can be suppressed. With respect to the extension of the lead terminal 2, the metal flow of the lead terminal 2 can be prevented from escaping or deforming to the side of the main body part 2-2 or the lead part 2-3 that is not restrained by the restraining jig 6. When the electrode foil 4 follows the elongation or deformation of the lead terminal 2, the electrode foil 4 may be stretched or thin. This may cause cracks in the electrode foil 4 on the main body part 2-2 side of the lead terminal 2. The second embodiment can avoid such inconvenience.

<Restraining jig 6>

  4A, 4B, and 4C show the inner shape of the restraining jig 6. FIG. In the restraining jig 6 shown in FIG. 4A, convex portions 24-1 and 24-2 are formed on the flat bottom portion 6-1. The convex portion 24-1 is formed on the opening 6-3 side so as to straddle the side wall portion 6-2. The convex part 24-2 is formed between the side wall part 6-2 opposite to the opening part 6-3.

  In the restraining jig 6 shown in FIG. 4B, in addition to the convex portions 24-1 and 24-2 (A in FIG. 4) on the bottom portion 6-1 of the restraining jig 6, the convex portion at the intermediate portion of the bottom portion 6-1. 24-3 is formed across the side wall 6-2. In other words, the restraining jig 6 includes a restraining concave portion that surrounds the bottom portion 6-1 with the side wall portion 6-2 and the convex portions 24-1 and 24-3, and the bottom portion 6-1 with the side wall portion 6-2 and the convex portion 24-2. , 24-3 is formed.

  In the restraining jig 6 shown in FIG. 4C, convex portions 26-1 and 26-2 are formed on the bottom 6-1 of the restraining jig 6. Each convex portion 26-1, 26-2 is formed at each pressing position of the press contact mold 14.

[Third Embodiment]

  In the third embodiment, by using the restraining jig 6 shown in FIG. 4A, after the preforming of the lead terminal 2, the cold connection with the electrode foil 4 is performed. FIG. 5A shows preforming of the lead terminal 2 according to the third embodiment. FIG. 5B shows the connection between the lead terminal 2 and the electrode foil 4.

  A flat part 2-1 of the lead terminal 2 is placed on the restraining jig 6, and an upper restraining jig 28 is installed on the upper surface of the flat part 2-1. The upper restraining jig 28 is formed with a through-hole 30 through which the press-contacting mold 14 passes. When the press contact mold 14 is pressed from each through hole 30 against the flat portion 2-1 on the restraining jig 6, a recess 32 is formed in the flat portion 2-1 by the press contact mold 14. In this embodiment, the tip end portion of the press contact mold 14 is hemispherical. Thereby, the recessed part 32 is shape | molded by the hemispherical hollow.

  After preforming the flat part 2-1, the electrode foil 4 is placed on the upper surface of the flat part 2-1, and a cold welding process is performed. The aforementioned pressure welding mold 14 is used for this pressure welding processing. An upper restraining jig 28 is installed on the upper surface of the electrode foil 4 on the flat part 2-1. Similar to the pre-molding, the press contact mold 14 is pressed from the through holes 30 against the electrode foil 4 on the flat part 2-1. Thereby, the electrode foil 4 is formed by pressing along the concave portion 32 in the flat portion 2-1, and the electrode foil 4 pressed against the inner surface of the concave portion 32 and the flat portion 2-1 of the extraction terminal 2 are cold-welded. Connected by

  In such preforming and cold welding, since the restraining jig 6 is provided with the convex portions 24-1 and 24-2, the flat part 2-1 of the lead terminal 2 is the opening 6-6 of the restraining jig 6. The metal flow to the 3 side can be suppressed. In this cold welding, since the lead-out terminal 2 is mounted on the convex portions 24-1 and 24-2, space is generated in the convex portions 24-1 and 24-2. The drawer terminal 2 deformed by the metal flow is accommodated in this space. For this reason, the metal flow of the flat part 2-1 to the width direction and axial direction (main-body part 2-2 direction) of the drawer terminal 2 can be reduced. Moreover, the metal flow of the flat part 2-1 to the opening part 6-3 side of the restraining jig 6 can be suppressed by the convex part 24-1, and the electrode foil 4 to the opening part 6-3 side of the restraining jig 6 can be suppressed. Can be prevented from stretching or deforming. As a result, the connection strength between the lead terminal 2 and the electrode foil 4 can be increased. Further, due to the convex portions 24-1 and 24-2, the pressing force by the pressure welding die 14 acts on the electrode foil 4 side as a repulsive force toward the concave portion 32, which increases the connection strength between the electrode foil 4 and the extraction terminal 2. Contribute to.

  In this embodiment, since the upper restraint jig 28 is provided, the preforming can prevent the lead terminal 2 from being deformed to the upper side, and the cold press welding can prevent the lead terminal 2 and the electrode foil 4 from being deformed to the upper side. .

[Fourth Embodiment]

  In the fourth embodiment, by using the restraining jig 6 shown in FIG. 4B, after the lead terminal 2 is preformed, the cold connection with the electrode foil 4 is performed. FIG. 6A shows preforming of the lead terminal 2 according to the fourth embodiment. FIG. 6B shows the connection between the lead terminal 2 and the electrode foil 4. In FIG. 6, the same parts as those in FIG.

  Similar to the third embodiment, a flat part 2-1 of the lead terminal 2 is placed on the restraining jig 6, and an upper restraining jig 28 is provided on the upper surface of the flat part 2-1. The upper restraining jig 28 is formed with a through-hole 30 through which the press-contacting mold 14 passes. When the press contact mold 14 is pressed from each through hole 30 to the flat portion 2-1 on the restraining jig 6, a recess 32 is formed in the flat portion 2-1 by the press contact mold 14. In this embodiment, the tip end portion of the press contact mold 14 is hemispherical. Thereby, the recessed part 32 is shape | molded by the hemispherical hollow. These matters are the same as in the third embodiment.

  In 4th Embodiment, since the convex part 24-3 is provided in the middle, the metal flow of the flat part 2-1 shape | molded by this convex part 24-3 is suppressed.

  After the preforming of the flat part 2-1, the electrode foil 4 is placed on the upper surface of the flat part 2-1, and a cold welding process is performed. The aforementioned pressure welding mold 14 is used for this pressure welding processing. An upper restraining jig 28 is installed on the upper surface of the electrode foil 4 on the flat part 2-1. Similar to the pre-molding, the press-contacting die 14 is pressed into contact with the electrode foil 4 on the flat part 2-1 from each through hole 30. As a result, the electrode foil 4 is formed along the concave portion 32 in the flat portion 2-1, and the flat portion 2-1 of the lead terminal 2 in the concave portion 32 is cooled by the electrode foil 4 pressed against the inner surface of the concave portion 32. Connected by intermediate pressure welding.

  In such preforming and cold welding, the lead-out terminal 2 is placed on the convex portions 24-1, 24-2, 24-3, and the convex portion 24 is interposed between the convex portions 24-1 and 24-3. -2 and a space between the convex portions 24-3. Each space accommodates a lead terminal 2 deformed by metal flow. For this reason, the metal flow to the width direction and axial direction (main-body part 2-2 direction) of the drawer terminal 2 can be reduced. The flat portion 2-1 of the lead terminal 2 can suppress the metal flow to the opening 6-3 side of the restraining jig 6 by the convex portion 24-1. Further, metal flow is suppressed for each press-contact mold 14. The elongation and deformation of the electrode foil 4 can be prevented. As a result, the connection strength between the lead terminal 2 and the electrode foil 4 can be increased.

  Also in this embodiment, since the upper restraining jig 28 is provided, it is possible to prevent the lead terminal 2 from being deformed to the upper side in the preforming, and in the cold welding, the lead terminal 2 and the electrode foil 4 are to be deformed to the upper side. To prevent.

  In this embodiment, since the extraction terminal 2 is formed so as to surround the press-contact connection portion 12 between the extraction terminal 2 and the electrode foil 4, deformation of the extraction terminal 2 in the length direction due to metal flow can be prevented. Thereby, extension to the main-body part 2-2 of the extraction terminal 2 of the electrode foil 4 is prevented, and it can prevent that a weak part is formed in the electrode foil 4. FIG.

  Since the press-connecting portion 12 is surrounded by the convex portions 24-1, 24-2, and 24-3, the metal flow of the lead terminal 2 in the peripheral portion of the press-connecting portion 12 can be suppressed. Moreover, if each convex part 24-1, 24-2, 24-3 receives pressing force, a repulsive force will be produced in each convex part 24-1, 24-2, 24-3, and this repulsive force and above-mentioned are mentioned. Since the electrode foil 4 and the extraction terminal 2 are sandwiched and pressed by the pressing force, the connection strength between the electrode foil 4 and the extraction terminal 2 can be increased.

[Fifth Embodiment]

  In the fifth embodiment, by using the restraining jig 6 shown in FIG. 4C, after the preforming of the lead terminal 2, the cold connection with the electrode foil 4 is performed. FIG. 7A shows preforming of the lead terminal 2 according to the fifth embodiment. FIG. 7B shows the connection between the lead terminal 2 and the electrode foil 4. In FIG. 7, the same parts as those in FIG.

  As in the third and fourth embodiments, the flat part 2-1 of the lead terminal 2 is placed on the restraining jig 6, and the upper restraining jig 28 is installed on the upper surface of the flat part 2-1. ing. The upper restraining jig 28 is formed with a through-hole 30 through which the press-contacting mold 14 passes. When the press contact mold 14 is pressed from each through hole 30 to the flat portion 2-1 on the restraining jig 6, a recess 32 is formed in the flat portion 2-1 by the press contact mold 14. In this embodiment, the tip end portion of the press contact mold 14 is hemispherical. Thereby, the recessed part 32 is shape | molded by the hemispherical hollow. These matters are the same as those in the third and fourth embodiments.

  In the fifth embodiment, since the convex portions 26-1 and 26-2 are provided in the middle, the flat portion 2-1 formed by the convex portions 26-1 and 26-2 is thinly formed. The Further, the flat portion 2 is formed between the convex portions 26-1 and 26-2, between the convex portion 26-2 and the restraining jig 6, and between the convex portion and the opening 6-3 of the restraining jig 6. Since the metal flow of -1 occurs, the extension of the lead terminal 2 to the lead portion 2-3 can be prevented. Thereby, it can prevent that a weak part arises in the electrode foil 4. FIG.

  After the preforming of the flat part 2-1, the electrode foil 4 is placed on the upper surface of the flat part 2-1, as in the third or fourth embodiment, and a cold welding process is performed. The aforementioned pressure welding mold 14 is used for this pressure welding processing. An upper restraining jig 28 is installed on the upper surface of the electrode foil 4 on the thinned flat part 2-1. Similar to the pre-molding, the press-contacting die 14 is pressed into contact with the electrode foil 4 on the flat part 2-1 from each through hole 30. As a result, the electrode foil 4 is formed along the concave portion 32 in the flat portion 2-1, and the electrode foil 4 pressed against the inner surface of the concave portion 32 and the flat portion 2-1 of the lead terminal 2 are connected by cold pressure welding. Is done.

  In such preforming and cold welding, since the electrode foil 4 is placed on the thin flat part 2-1, and the pressure connection is made, the metal amount of the flat part 2-1 pressed by the pressure connection can be reduced, and the lead terminal 2 metal flow can be suppressed. Thereby, the elongation and deformation of the electrode foil 4 can be prevented. As a result, the connection strength between the lead terminal 2 and the electrode foil 4 can be increased.

  Also in this embodiment, since the upper restraining jig 28 is provided, it is possible to prevent the lead terminal 2 from being deformed to the upper side in the preforming, and in the cold welding, the lead terminal 2 and the electrode foil 4 are to be deformed to the upper side. To prevent.

  In this embodiment, when the recess 32 is formed in the extraction terminal 2, the periphery of the connection portion of the extraction terminal 2 is simultaneously thinned. For this reason, the thinned portion of the extraction terminal 2 can reduce the portion and metal that extend due to the pressure contact with the electrode foil 4, and the metal flow of the extraction terminal 2 and its deformation amount are suppressed. As a result, the deformation of the electrode foil 4 following the metal flow and deformation of the lead terminal 2 can be suppressed, and cracking of the electrode foil 4 is prevented.

[Other Embodiments]

  (1) In the above embodiment, the connection between the electrode foil and the lead terminal is shown in the capacitor manufacturing process. It goes without saying that the manufacture of a capacitor includes the formation of a capacitor element using an electrode foil connected with a lead terminal, an impregnation step with an electrolytic solution, a sealing step in an outer case, and a sealing step in the outer case.

  (2) In the above embodiment, the connection between the capacitor element of the electrolytic capacitor and the lead terminal is exemplified. The present invention is not limited to the above embodiment, and can be used for other capacitors such as an electric double layer capacitor.

  (3) In the above embodiment, the tip shape of the pressure contact mold 14 is a spherical shape or a hemispherical shape, but it may be a frustoconical shape with a sharp corner portion tapered. If there is a corner at the tip of the press-contacting mold 14, stress concentration occurs when the corner is pressed against the electrode foil 4. This stress concentration may cause excessive stress from the corners to the pressed portion of the electrode foil, which may cause cracking or foil cracking of the electrode foil 4. On the other hand, if the tip shape of the pressure contact mold 14 is hemispherical as in the above embodiment, stress concentration can be avoided and cracking and foil cracking of the electrode foil 4 can be prevented. If the tip shape of the pressure welding die 14 is spherical or hemispherical, during cold pressure welding, the stress applied to the electrode foil 4 from the pressure welding portion is caused to act radially from the pressure welding portion, and the stress can be made uniform. Concentration can be avoided.

  (4) Also in the first and second embodiments, preforming may be performed in the same manner as in the third, fourth, and fifth embodiments. In the press-contact connection between the preform and the electrode foil 4, the same press-contact mold 14 is used, but the present invention is not limited to this. You may make the expansion angle of the recessed part 32 shape | molded by preforming larger than the angle of the press-contact metal mold | die 14 used for press-contact connection with the electrode foil 4. FIG. By doing so, the electrode foil 4 is not sandwiched between the opening edge of the recess 32 and the press-contacting mold when the press-connecting is performed in the recess 32, and is pressed evenly in the recess 32. That is, the electrode foil 4 sandwiched between the press-contact mold 14 and the recess 32 of the lead terminal 2 is pressed from the gap between the press-contact mold 14 and the inclined surface portion of the recess 32 of the lead terminal 2. The concave portion 32 is guided in the concave portion 32 as the bottom surface side of the concave portion 32 moves. Since the expansion angle of the inclined surface portion of the recess 32 is larger than the expansion angle of the press-contacting mold 14, the angle difference creates a space, and the electrode foil 4 can be moved in this space.

  In the movement of the electrode foil 4 by the gap between the concave portion 32 and the electrode foil 4 pressed by the pressure contact mold 14, the fixed portion is fixed between the inclined surface portion of the concave portion 32 of the lead terminal 2 and the inclined surface portion of the pressure contact mold 14. There is no part to be done. That is, there is no trigger or starting point for local stretching of the electrode foil 4, and stretching can be prevented. The electrode foil 4 moves at the tip of the press-contacting mold 14 until the electrode foil 4 reaches the bottom surface of the recess 32. That is, the electrode foil 4 is formed into the inner shape of the recess 32 while being uniformly stretched without being stretched locally.

  The electrode foil 4 that has reached the bottom surface side of the recess 32 is pressed into contact with the extraction terminal 2 by the press contact mold 14, and the electrode foil 4 is connected to the extraction terminal 2.

  In this manner, the electrode foil 4 is not fixed in the process of forming the electrode foil 4 with respect to the movement of the press contact mold 14, so there is no local elongation of the electrode foil 4, and the inclined surface portion of the recess 32 of the electrode foil 4 and the extraction terminal 2 Without accompanying the elongation of the electrode foil 4, the pressure stress that uniformly presses the electrode foil 4 to the bottom surface portion and the inclined surface portion of the recess 32 is dispersed. By this dispersion, uniform pressure welding is performed, the elongation of the electrode foil 4 is uniformly extended, the electrode foil 4 can be gradually thinned and prevented from being stretched locally, and local thinning and weakening due to elongation are prevented. Can be prevented. Further, stress concentration can be prevented. As a result, the connection strength between the electrode foil 4 and the lead terminal 2 can be increased.

As described above, the most preferable embodiment of the present invention has been described. The present invention is not limited to the above description. Various modifications and changes can be made by those skilled in the art based on the gist of the invention described in the claims or disclosed in the embodiments for carrying out the invention. It goes without saying that such modifications and changes are included in the scope of the present invention.

The present invention can prevent deformation such as elongation of the extraction terminal when performing cold pressure welding for connection between the extraction terminal and the electrode foil. The elongation and thinning of the electrode foil following this elongation can be prevented, and the weakening of the electrode foil can be avoided. The connection strength between the electrode foil and the lead terminal can be increased. This contributes to improving the reliability of the capacitor and is extremely useful.

DESCRIPTION OF SYMBOLS 2 Lead terminal 2-1 Flat part 2-2 Main body part 2-3 Lead part 4 Electrode foil 4-1 Base metal part 4-2 Processing layer 6 Restraint jig 6-1 Bottom part 6-2 Side wall part 6-3 Opening part 8 Cavity 10 Space part 12 Pressure connection part 14 Pressure contact mold 16 Spherical part 18 Columnar part 20 Conical part 22 Through part 24-1, 24-2, 24-3 Convex part 26-1, 26-2 Convex part 28 Upper side Restraint jig 30 Through hole 32 Recess

Claims (4)

On at least the side surface of the lead terminal connected to the electrode foil, a restraining jig having a space portion that allows deformation of the lead terminal and prevents deformation beyond a desired permissible deformation amount is installed between the lead side and the side surface. Process,
A step of stacking the lead terminal and the electrode foil;
Pressing the pressure contact mold from above the electrode foil, allowing the deformation of the restraining jig to the space, and connecting the lead terminal and the electrode foil; and
A method for producing a capacitor, comprising: Further, the restraining jig includes a single or a plurality of convex portions on a surface portion that comes into contact with the extraction terminal, and the step of disposing the extraction terminal on the surface portion;
Superimposing the electrode foil on the lead terminal;
Connecting the lead terminal and the electrode foil by pressing a pressure contact mold from above the electrode foil;
The method of manufacturing a capacitor according to claim 1, comprising: A step of pressing a pressure contact mold against the lead terminal to form a recess by the pressure contact mold on the lead terminal and a recess by the convex portion of the restraining jig;
The method for manufacturing a capacitor according to claim 2, comprising:   4. The method of manufacturing a capacitor according to claim 2, wherein the convex portion of the restraining jig is formed at an end portion in an axial direction of the lead terminal. 5.

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