Constant monitoring of area around laser beam welding process - to determine degree of weld spitting by monitoring brightness centres

摘要

Method of on-line monitoring the effect of a laser beam on the surface of a workpiece, esp. during welding consists of using the laser beam focussing device to direct the emitted light (13) from the area around the work area (11) to cylindrical lenses (A,B) which focus the light onto two receiver units (A'B') arranged at an angle to each other and built as single dimension working receiver lines. These receivers send out electric signals to an evaluation unit which produces data concerning the local and/or statistical brightness distribution of the area (11). ADVANTAGE - The monitoring takes place without stopping the welding process.