| 摘要 |
<p>PROBLEM TO BE SOLVED: To cut a thick plate workpiece accurately and at high speed by eliminating cutting defects in the deep part of the thick plate workpiece which is a problem in a conventional laser cutting method. SOLUTION: In this laser cutting processing method by which the irradiation position of a laser beam is moved in a cutting direction P to cut the workpiece while carrying out irradiation of the laser beam and the feed of an assist gas towards the workpiece 4 of a thick plate metallic material from a processing head 1 provided with a condensing lens 3 and an assist gas lead-in opening 2b, an auxiliary torch 5 provided with a condensing lens 6 is additionally equipped behind the processing head 1, and the laser beam is used as a main laser beam, and the auxiliary torch is directed to the deeper part of a workpiece cutting plane 4a to be irradiated with an auxiliary laser beam. Power attenuation associated with the reflection of the main laser beam is compensated by the auxiliary laser beam. Thereby, a cutting delay in the workpiece rear side and a cutting failure which are the problems in the conventional laser cutting processing method are prevented to enable the high-speed cutting of the thick plate workpiece.</p> |
