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:
Oct. 24, 2000
Filed:
Aug. 09, 1999
Kyoji Moro, Chiba-ken, JP;
Hiroshi Shimada, Chiba-ken, JP;
Miyachi Technos Corporation, Chiba-ken, JP;
Abstract
When a second switching element Q.sub.2 is changed over from ON state to OFF state for each switching cycle while a first switching element Q.sub.1 remains ON in a unit weld period T.sub.a for example, a primary current I.sub.1 does not come to a stop at once under the influence of inductance of a welding transformer 16 but it flows as a transient current i through a primary circuit until it is off. The transient current i makes a closed circuit through which it flows from a primary coil of the welding transformer 16 via a third diode D.sub.3 and then a first switching element Q.sub.1 again into the primary coil of the welding transformer 16. More specifically, due to the first switching element Q.sub.1 being kept ON, the transient current i which has passed through the third diode D.sub.3 flows through the first switching element Q.sub.1, without passing through a capacitor 12, and comes back into the primary coil of the welding transformer. Little or substantially no current flows through the capacitor 12.