| 摘要 |
PURPOSE:To efficiently cut even a subject having a thick wall by discharging the molten dross while preventing it from being cooled without adverse influence on the condenser lens. CONSTITUTION:In a nozzle 10 for the laser beam, the laser beam 16 is projected orthogonally crossed to the surface of concrete 20 on the top end of a nozzle hole 18 through a condenser lens 14, and converged at a slightly deep spot from the front surface. The concrete 20 is molten and cut by utilizing the thermal phenomenon at this focus position F. A nozzle 22 for an assist gas is arranged at the rear part side of the cutting direction of the nozzle 10 facing its nozzle hole 24 toward the focus position F, and moved in the cutting direction shown by the arrow mark together with the nozzle 10. A heater 26 is arranged at the rear part of the nozzle 22, which heats the assist gas 30 fed toward the nozzle hole 24 with the prescribed pressure. |
