Patent ID: 8537526

Claim:
A capacitor comprising: a capacitor element formed by winding a first sheet-shaped electrode and a second sheet-shaped electrode with a separator interposed between the electrodes, and displacing the first electrode and the second electrode in opposite directions each other; a bottomed, cylindrical, metallic case housing the capacitor element together with a driving electrolytic solution, the first electrode being joined to the case; a metallic terminal plate having a cylindrical section including an outer peripheral surface, and a disc-shaped flange provided along a bottom surface of the cylindrical section and extending beyond the outer peripheral surface of the cylindrical section, the second electrode being joined to the terminal plate; and a sealing rubber in a ring shape in contact with an extended top surface of the flange of the terminal plate, the outer peripheral surface of the cylindrical section of the terminal plate, and the metallic case, the sealing rubber sealing the metallic case; wherein the metallic case is wrung from an outer side of a side surface of the metallic case to form a side groove wrung part compressing the sealing rubber toward the outer peripheral surface of the cylindrical section of the terminal plate, an end of the opening of the metallic case is curled to an inner diameter side of the metallic case so as to form a curled portion having an arc sectional shape, and the curled portion is in press-contact with the sealing rubber; and a single ring-shaped top projection wall is provided on a top face of the sealing rubber and located between the terminal plate and the curled portion and extends substantially parallel to the outer peripheral surface of the cylindrical section of the metallic terminal plate, an upper tip of the ring-shaped top projection wall is as high as an upper end of the curled portion or lower than the upper end of the curled portion, and higher than an upper tip of a portion of the sealing rubber, the portion of the sealing rubber being located inside the curled portion, an inner surface of the ring-shaped top projection wall and an inner surface of the sealing rubber lie in a same plane, and a gap is provided between an outer surface of the ring-shaped top projection wall and an inner surface of the curled portion, wherein a ring-shaped bottom projection wall projecting between the metallic case and the flange is provided on a bottom face of the sealing rubber, and wherein a gap is provided at a location, the location is at least one of a location between the ring-shaped bottom projection wall and the metallic case and a location between the ring-shaped bottom projection wall and the flange.