| 摘要 |
<p>PROBLEM TO BE SOLVED: To easily detect the generation of defective cut part, and to easily detect even especially under in-process during machining by sampling an optical energy level of lower side range from the central part of the front face of cut part in the generation of various defective cut part. SOLUTION: An image-formation optical system 4 is always positioned at an upper stream side of a cutting line 2A of already cut with a laser beam 3, and it is arranged so that the lower side part of a cut part fore face 2 is always observed directly. The light energy of the lower side part of the cut part fore face 2 sampled with the image-formation optical system 4 is transmitted to a photoelectric converter 6 with an optical fiber 5, it is picked up as an electric output corresponding to the light energy of the cut part fore face 2 and it is sent to a computer 7. In the computer 7, in a case of generating a defective cut part at the cut part fore face 2 position, because the change of the electric output is generated, so the generation of the defective cut part is judged easily with the computer 7 side, a signal of cutting stop is transmitted to a controller 8 and cutting is stopped.</p> |
