| 摘要 |
PURPOSE:To detect reflected beams in a maximum reflected light region and realize an excellent welding position detection, by detecting reflected beams of a laser beam from a welding position with a light receiving mirror and photoreceptor sensor, both of which are installed in a welding head. CONSTITUTION:An He-Ne laser beam 4 for detecting welding position is oscillated in addition to a CO2 laser beam 2 for welding by overlapping the laser beam 4 upon the laser beam 2, and the laser beams are irradiated upon an object to be welded 10 through a condenser lens 8 and folded mirror 6. The reflected amount of the above mentioned He-Ne laser 4 is detected by a photoreceptor sensor 12 through a light receiving mirror 14 and small-sized lens 15 installed in the space between the condenser lens 8 and folded mirror 6, and a welding head is oscillated in the left-right direction with a welding groove 13 at the center, and thus the welding position can be easily judged by a minimum amount of reflected light. At the time of welding, the light receiving mirror 14 can be retracted from the optical path by bringing up the bodytube 16 of the photoreceptor sensor 12, and, moreover, influence of weld fume is minimized because a welding shield gas 17 is supplied into the welding head 7. |
