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:
Jun. 18, 1996
Filed:
Nov. 25, 1994
Kazusue Itoga, Kawasaki, JP;
Junzo Tanaka, Kawasaki, JP;
Fuji Electric Co., Ltd., Kanagawa, JP;
Abstract
Semiconductor switching elements (inverse-parallel connected thyristors) of each main circuit element unit are connected in parallel to a main contact of an electromagnetic contactor. An operation input voltage signal applied to an electromagnetic coil of the electromagnetic contactor is detected by an input-voltage detecting circuit of a control section. When the electromagnetic contactor is closed and opened, a one-shot-pulse generating unit outputs a one-shot pulse based on an output of the input-voltage detecting circuit and a signal indicating an opening/closing state of an auxiliary normally-closed contact of the electromagnetic contactor. The semiconductor switching elements are made on only for a short time by a firing circuit based on the one-shot pulse, to turn on and off a load current.