METHOD AND APPARATUS IN ARC WELDING

摘要

Method and apparatus in arc welding with movable electrode (E) for detecting the movement of the welding arc (B) with respect to a given location, employ a microphone (M) placed at said given location to pick up sound emitted from the welding arc (B) in order to detect variations of the picked up sound as a representation of the movement of the arc (B) with respect to the microphone (M). The sound emitted by the welding arc (B) and picked up by the microphone (M) is either welding noise produced by the welding process itself or discrete frequency sound generated in the welding arc (B) by superimposed an A.C. signal on the welding current. The detected variations of sound picked up by the microphone (M) is preferably utilised for producing a control signal for controlling the movement of the welding electrode (E), in particular when the electrode is made to perform a weaving motion across the welding joint (F).