ALUMINUM ELECTROLYTIC CAPACITOR

PURPOSE:To prevent gas of driving electrolytic solution from flowing to the outside by providing a space part above an explosion-proof valve provided to a top board part of a metallic case, by providing a first absorbing material to the explosion-proof side positioned inside the space part and by providing a buffer board and a second absorbing material to the outside. CONSTITUTION:Fiberglass, porous hypolymer, etc., are used as first and second absorbing materials 9, 11. When an overvoltage above the rated value is applied to an aluminum electrolytic capacitor, an internal ressure of a metallic case 2 rises, thereby allowing an explosion-proof valve 6 provided to a top board part 2a to start, and driving electrolytic solution in the inside ejects from the explosion-proof valve 6. In the process, gas of driving electrolytic solution is partially absorbed by the first absorbing material 9. Gas of driving electrolytic solution which is not absorbed by the first absorbing material 9 falls on a lower surface of the buffer board 10 having a small hole 10a and most thereof is cooled and liquified, and drops. Since gas of driving electrolytic solution which passes through the small hole 10a of the buffer board 10 is absorbed by the second absorbing material 11 provided outside the buffer board 10, driving electrolytic solution does not leak to the outside.