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. 11, 1990
Filed:
Jan. 19, 1989
Applicant:
Inventors:
Jun-ichi Nishizawa, Sendai, JP;
Takashige Tamamushi, Sendai, JP;
Koji Ishibashi, Tagajo, JP;
Kiyoshi Wagatsuma, Tagajo, JP;
Assignees:
Tohoku Electric Manufacturing Co., Ltd., Tagajo, JP;
Zaidan Hojin Handotai Kenkyu Sinkokai, Sendai, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G05F / ;
U.S. Cl.
CPC ...
323244 ; 323902 ;
Abstract
A pair of static induction thyristors, which are coupled in parallel in the opposite bias directions between an AC power source and a load, is turned on by a light signal and is turned off by natural commutation, a light signal or an electric signal. The turn-off light signal is generated within a phase angle of 90.degree. in the time axis around the zero-cross point of the AC voltage from the AC power source.