| 摘要 |
<p>PROBLEM TO BE SOLVED: To accurately detect the end of a plate material even if the shape of the end is deformed in the material. SOLUTION: In a state where a plate 7 to be cut is placed on a cutting base 8, cutting is started for the plate 7 by holding a laser cutting torch 1 near the end of the plate 7 with a specific space apart from the plate while an assist gas is supplied; then, a micro differential pressure detecting sensor 6 successively detects the inner pressure of an injecting pressure collecting cover 5, sending it to the comparator of a plate end detecting part. During the movement of a laser cutting torch 1, the comparator makes a comparison between the inner pressure of the injecting pressure collecting cover 5 detected by the micro differential pressure detecting sensor 6 and a preliminarily set threshold value; and, if the inner pressure is detected becoming smaller than the threshold value, the comparator transmits a signal showing the change in the inner pressure to a plate end discriminating part. The plate end discriminating part, receiving the signal showing the change in the inner pressure, decides that the nozzle of the laser cutting torch 1 has reached the end of the plate 7.</p> |
