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:
May. 06, 2008
Filed:
Sep. 29, 2005
Kazunari Tezuka, Sagamihara, JP;
Kazunari Tezuka, Sagamihara, JP;
NEC Corporation, Tokyo, JP;
Fuji Jukogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A method for detecting a welding of a relay contact in a circuit having a DC power supply; a load circuit; a first main relay and a second main relay respectively inserted in a pair of power supply lines disposed between the DC power supply and the load circuit; and a precharge relay which is provided in parallel to the contact of the first main relay has the step of carrying out a sequence control to each of the relays () while measuring voltage across both ends of the load circuit () when shifting from a normal operation state in which a first main relay () and a second main relay () are controlled to be on and the precharge relay () is controlled to be off to a suspension state in which each of the relays () are controlled to be off. The welding of the relay contact of the first main relay () and the second main relay () is determined independently and separately from a correspondence between the proceeding of the sequence and the measured voltage.