Verfahren und Laserbearbeitungskopf mit einer Einrichtung zur Überwachung eines optischen Elements eines Bearbeitungskopfes einer Maschine zur thermischen Bearbeitung eines Werkstücks

摘要

The monitor (1) for an optical component (4) at the working head of a laser cutting or welding machine, to check for dirt soiling, registers scattered light (10) at it and also scattered light (17) as a reference from a second optical component (3). The scattered light (13) is registered in the space (14) between the two optical units. The monitor signals are converted to logarithms and evaluated (20-23) to give the difference between the logarithms of the registered measurement signal and the reference value. The scattered light levels are detected by photo diodes (15,16,19). The optical component and the evaluation system are contained within a sliding cassette, which has an illuminated display to indicate the soiling level.