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:
Oct. 04, 2005
Filed:
Feb. 07, 2001
Masayuki Sakaki, Shizuoka, JP;
Hiroaki Sano, Shizuoka, JP;
Masayuki Sakaki, Shizuoka, JP;
Hiroaki Sano, Shizuoka, JP;
Kabushiki Kaisha Meidensha, Tokyo, JP;
Abstract
Detection of degradation of the degree of vacuum in a vacuum interrupter suffers from poor sensibility because of mixed presence of various noises other than that due to discharge resulting from degradation The present invention allows accurate detection of degradation of the degree of vacuum by detecting the continuity of discharge produced between an electrode and a shield due to degradation of the degree of vacuum and the duration of discharge. The continuity of discharge is detected in accordance with a time slightly longer than 1 cycle time of a power-source voltage, and the duration of discharge is detected in accordance with a time sufficiently longer than 1 cycle time.