| 摘要 |
<p>A method of accurately resuming laser beam machining without leaving any portions unprocessed when processing is interrupted during laser beam machining. When laser beam machining has progressed a distance L0 from a processing point P1 and abnormal processing is detected at a processing point P3, a computerized numerical control receives the detection signal of abnormal processing to go into retry processing. Namely, laser beam machining is first suspended and the position of the processing point P3 at the time of suspension is stored. Then, a processing head is retracted a distance h0 in a Z axis direction and is reversed a distance L2 along a processing path L along which processing has been executed theretofore. When reversing is completed at a point P6, a gap between the nozzle and the work piece is controlled, and laser beam machining is resumed when approaching has completed. When the computerized numerical control again receives a detection signal of abnormal processing during forward movement of the processing head from a processing point P7 to a processing point P4, the above retry processing is again performed. When the number of such repetitions exceeds a predetermined number of times n0, for example, three times, processing of the block being processed is skipped, and processing proceeds to the subsequent block.</p> |
