The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 01, 2007
Filed:
Jun. 14, 2005
Toshiaki Shimizu, Nara, JP;
Toshihiko Oohashi, Osaka, JP;
Toshiaki Shimizu, Nara, JP;
Toshihiko Oohashi, Osaka, JP;
Matsushita Electrid Industrial Co. Ltd., Osaka, JP;
Abstract
A method for determining the deterioration of a capacitor that increases the measurement accuracy to have an improved reliability is disclosed. In this method for determining the deterioration of a capacitor, the deterioration of a capacitor including a pair of electrode bodies and electrolytic solution provided between the electrode bodies is determined by applying an AC voltage to the capacitor to measure an impedance characteristic at a frequency of the AC voltage. An inflection point appearing in the impedance characteristic due to the deterioration of the electrolytic solution is previously calculated to make comparison with an impedance value in the frequency region lower than the inflection point, thereby determining the deterioration.