LASER BEAM MACHINE

PURPOSE:To eliminate the variation of an electrostatic capacity by a generated plasma, to control a gap constantly and to maintain good working accuracy by providing a recessed part at the body to be worked side of the tip nozzle controlling the gap with the electrostatic capacity. CONSTITUTION:A recessed part 18 is provided at the side of the body to be worked of the tip nozzle 17 provided via the insulating body 8 of a laser machining head 4. This nozzle 17 optimizes a focusing position 6 by controlling its gap G with the body 7 to be worked constantly with the detection of an electrostatic capacity 11. Since the plasma 16 generated by the projection of a laser light 2 does not come into contact with the nozzle 17 directly by the recessed part 18, no variation is given to the electrostatic capacity, the gap G is always constantly controlled and the laser machining accuracy is well maintained.