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:
Jan. 06, 1987
Filed:
Nov. 19, 1985
Masato Furudate, Kanagawa, JP;
Abstract
A method of controlling constant-current for resistance welding machines comprising the steps of: detecting the welding current flowing into the primary coil or the secondary coil of a welding transformer, applying a first half-wave current having a predetermined first phase control angle, detecting the current value and the current conduction angle at that time, calculating a power factor angle of the resistance welding machine from the detected conduction angle and the phase control angle, calculating a second phase control angle, by which a current value corresponding to a previously set value of the next half-wave of current is obtained, from the calculated power factor angle, the detected conduction angle and the detected of current value, applying the next half-wave current at the second phase control angle through a thyristor circuit to a work to be welded, and repeating the above control operation during an entire welding cycle.