| 摘要 |
<p>A laser machining apparatus adapted to apply a laser beam to a work and cut the same. The cutting of a work of a nonferrous metal is done efficiently and stably, and the cutting of even a work of a large thickness is also done. In a point A, a boring process is carried out under a machining condition A to form an arcuate portion (31). The machining condition is then switched to B, and an expansion treatment is carried out to form an expanded bore (32) in an extended form of the original arcuate portion (31). When the expansion treatment has completed in the position B, the stand-off (distance between the front end of a machining nozzle and the surface of the work) is set to a lowest possible level, and the machining condition is switched to C, under which a cutting process is started. Therefore, the cutting process is carried out in substantially the same manner as in a process in which the cutting of a work is started directly from the outer side of an end portion thereof. During the cutting process, the pressure of an assist gas is set high, and the stand-off small, so that the dross scattering effect by the assist gas is displayed more remarkably. Accordingly, a cutting process can be carried out efficiently and stably.</p> |
