| 摘要 |
PURPOSE:To meet variation of the distance between a lens barrel and a workpiece only by moving a lens by arranging the lens at the front stage side in the incident direction from a mirror in the elbow-shaped lens barrel and sliding the lens in the direction of an optical axis according to the distance between the other end face of the lens barrel and the workpiece. CONSTITUTION:A laser beam Le introduced through the inside of an arm 1 from a laser beam oscillator is reflected by the mirror 5 and transmitted through the lens 28 and then, further converged and reflected by a converging mirror 26 and the workpiece W is irradiated from a tip opening 37 of a nozzle 12. At this time, when the height of the workpiece W is changed due to unevenness, etc., of the workpiece W and the distance C between the workpiece W and the tip of the nozzle 12 is changed to C', the laser beam Le can be focused on the surface of the workpiece W and welding can be performed under speci fied welding conditions regardless of variation of the distance by moving the lens 28 up to the virtual line position P. |
