| 摘要 |
PURPOSE:To nearly constantly maintain the density of the irradiation energy of a laser beam by making the beam diameter nearly constant. CONSTITUTION:The torch is provided with a reflection mirror 29 that is arranged proximately separably against the lens 22 to which the laser beam 5 is converged, a range finder sensor 36 by which distance is measured to the inside face of a piping 3 placed opposite to the mirror 29, a computing element 37 by which a position to move the mirror 29 is obtained based on the range finder signal 38 from the sensor 36, a controller 39 by which a driving signal 41 is outputted based on a position setting signal 40 from the computing element 37, and a servo motor 30 for moving by which the mirror 29 is proximately separated against the lens 22 based on the driving signal 41. Then, the mirror 29 is moved in accordance with the distance to the inside face of the piping 3, and the beam diameter of the laser beam 5 entering into the inside surface of the piping 3 is made to be a nearly constant size. |
