| 摘要 |
PURPOSE:To perform laser cutting normally without self-ignition phenomena by subjecting the work piece to laser working in the presence of auxiliary gases except pure oxygen in the stage of working an under hole, and cooling the work piece, then maintaining the gaseous oxygen to be used during cutting at high purity and cutting the work piece by a laser. CONSTITUTION:Laser light 2 is introduced into a lens barrel 3, and solenoid valves 11b and 11d are opened to eject pressurized air through the passage hole 21 of a nozzle 16 and air holes 22... to a work piece 13. While the air is ejected simultaneously from a nozzle 26 for removing, the work piece 13 is opened with an under hole by the laser light 2. After the machining of the under hole, the valves 11b, 11d are closed, and the under hole part is cooled with the pressurized air for cooling from an annular pipe 29. The laser light is conducted to a heat absorbing body by the 3rd reflecting mirror, and the irradiation is stopped. When the under hole is throughly cooled, again the lens barrel 3 is returned to the working position for the under hole, and the valves 11a, 11b are changed over so that the pressurized gaseous oxygen is ejected from the nozzle 16. While the 1st and 2nd driving mechanisms 21 are controlled, the 1st reflecting mirror and the barrel 3 are moved, whereby the work piece is cut. |
