Patent ID: 9044817
Filing Date: 2015-06-02
Classification: B23K

Abstract:
1. An electrode position control method for tandem arc welding which controls positions of a leading electrode and a trailing electrode with respect to a weld line prior to start of welding a welding workpiece, comprising: a voltage applying step of applying a voltage to the leading electrode and the trailing electrode; a voltage detecting step, performed during the voltage applying step, of bringing the leading electrode and the trailing electrode into contact with the welding workpiece to be welded and detecting voltages on the leading electrode and the trailing electrode that are brought into contact with the welding workpiece to be welded, wherein said voltage has a value that does not generate an arc between the welding workpiece and the respective leading electrode or trailing electrode when the leading electrode and the trailing electrode have not yet been brought into contact with the welding workpiece; a sensing step of detecting positional information of the welding workpiece from electrical changes in the voltages on the leading electrode and the trailing electrode detected in the voltage detecting step; a correction amount calculating step of calculating a correction amount for correcting for positional displacement of each of the leading electrode and the trailing electrode with respect to the weld line that has been previously taught, from the positional information of the welding workpiece detected in the sensing step; and a position correcting step of correcting the positions of the leading electrode and the trailing electrode with respect to the weld line, by adding or subtracting the correction amount calculated in the correction amount calculating step.