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:
Mar. 03, 1998
Filed:
Apr. 26, 1996
Applicant:
Inventors:
Eiji Nakayama, Hitachinaka, JP;
Shigeru Shinohara, Hitachinaka, JP;
Masateru Niyada, Hitachinaka, JP;
Assignee:
Hitachi Koki Co., Ltd., Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01H / ;
U.S. Cl.
CPC ...
307125 ; 307130 ; 307139 ;
Abstract
Re-powering an electrical equipment after recovery of service interruption is prevented if the power switch of the electrical equipment stays in ON position. During a transit period of time just after recovery of service interruption, the detection voltage from a post-voltage detection circuit is set to exceed the detection voltage from a pre-voltage detection circuit. In this condition, a photo triac connected in series to the power switch is rendered non-conductive so that the electrical equipment will not be energized.