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:
Aug. 02, 1983
Filed:
Oct. 22, 1981
Masayasu Nihei, Hitachi, JP;
Satoshi Kokura, Hitachiota, JP;
Eiji Ashida, Hitachi, JP;
Yuzo Kozono, Hitachi, JP;
Akira Onuma, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a welding apparatus having a plurality of electrodes and adapted for carrying out welding operation on a workpiece by alternately supplying currents to the individual electrodes through switching elements, an apparatus and method of controlling the currents supplied to the electrodes, comprising selecting the values of the currents supplied to the individual electrodes depending on the material of the workpiece, and carrying out the welding operation on the workpiece by alternately supplying the currents of the selected values to the individual electrodes respectively through the switching elements. The method is featured by the fact that the ratio between the individual currents is selected under the condition that the sum of the values of all the currents is maintained at a predetermined value. It is also featured by the fact that, depending on the welding condition, the values of the individual currents can be freely selected without the limitation of maintaining the sum of all the currents at the predetermined value. Therefore, the apparatus and method are applicable to welding of a variety of materials by selecting the values of the individual currents depending on whether the workpiece has a high or low melting point and also whether the workpiece has a high or low heat conductivity.