METHOD AND APPARATUS FOR LASER CUTTING WITH DOUBLE-FLOW AND DOUBLE-FOCUS CUTTING HEAD

摘要

PROBLEM TO BE SOLVED: To provide a method and an apparatus by which structural steel is cut while minimizing or removing the layer of surface oxide and on the other hand metal coated by a plastic film is cut while vaporizing a surface layer film. SOLUTION: In the method and the device, a main laser beam 10 is generated by a laser generator, the main laser beam 10 is divided into two subsidiary laser beams and a workpiece is separately irradiated with the subsidiary laser beams from two outlet nozzles 3 and 4 which are coaxially formed respectively by a first optical means 1. A central beam 11 is condensed on a focus (RF) by a first condensing means 1 and also the other beams are focused onto an annular focusing zone (ZAF) by a second focusing means 2.