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:
Sep. 05, 1989
Filed:
Apr. 13, 1988
Youichi Ohshita, Hitachi, JP;
Akira Hashimoto, Hitachi, JP;
Masanori Tsukushi, Hitachi, JP;
Yukio Kurosawa, Hitachi, JP;
Kiyoshi Okumura, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Disclosed is a switch operation monitoring apparatus for quickly and accurately detecting an abnormal operation of an actuating mechanism actuating a switch such as a power circuit breaker. A normal characteristic stroke of a moving part of the actuating mechanism is previously calculated on the basis of an interrupting current waveform, an environmental gas pressure and an actuating fluid pressure while taking into account the structure of the switch so as to use the calculated characteristic stroke as a reference stroke, and this reference stroke is compared with an actually measured characteristic stroke to decide whether the operation of the actuating mechanism actuating the switch is normal or abnormal.