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:
Dec. 30, 1986
Filed:
May. 28, 1985
Hiroshi Kashiwazaki, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An applied voltage detecting device for an electric power convertor is disclosed which detects a forward voltage and a backward voltage applied to a power convertor consisting of a semiconductor power control rectification element. The forward and backward voltages are detected by a detecting circuit while a relative potential difference is being provided to these voltages. The voltages detected by the detecting circuit are converted to optical signals and are picked up by a single optical transmission circuit. The optical signal is again converted to the electric signal by a discrimination circuit, which discriminates whether the signal is the forward detection voltage or the backward detection voltage from the potential difference between them. The present invention can simplify the detecting device because both forward and backward voltages can be detected by the single optical transmission circuit.