Laser beam machining apparatus and laser beam machining method

摘要

A laser beam machining apparatus forms blind holes at predetermined intervals in a workpiece by intermittently irradiating a laser beam from a laser nozzle to the workpiece while the laser nozzle and the workpiece being moved relatively. During the time the workpiece is subjected to machining, the electrostatic capacity between the support member 11 and the laser nozzle is detected by an electrostatic capacity sensor 19 while the workpiece made of conductive material is supported on the support member. The irradiation output power is controlled by a control unit which operates to vary the number of output pulses from the laser nozzle each time one hole is formed according to the result detected in response to variation in the thickness of the workpiece.