| 摘要 |
PURPOSE:To eliminate loss in piercing time by detecting a piercing completion based on an optical detection from the side of a work surface and thereby performing the detection at a low cost and also accurately. CONSTITUTION:The laser beam machining device 1 is provided with, an optical sensor 7 by which a light beam generated on the machining face of a work W is detected; a differentiator 8 by which the variation of a light beam strength detected by the optical sensor 7 is detected; a comparator 9 by which a detecting signal C is outputted only when the optical variation detected by the differentiator 8 is the same as or more than a predetermined reference value; a counter 10 by which a signal F for a piercing completion is outputted only when, whether the detecting signal C from the comparator 9 is continuous or not is counted with a timing synchronous with the oscillating signal A of the laser beam at the time of piercing, and the counted value E is the same as or more than the reference count previously set; and a NC control device 2 by which a command for a transition to a cutting process is executed based on one signal F for the piercing completion. |
