| 摘要 |
PURPOSE:To prevent the strain of a converging lens by welding by injecting a high speed gas obliquely in the laser beam progressing direction and providing a discharging means at the downstream in a work head between the converging lens and the body to be worked. CONSTITUTION:A laser beam 1 is converged on the surface of the body 5 to be machined by a converging lens 2 and a shielding gas is injected from an injection port 4 to perform the laser beam welding of the body 5 to be worked. At this time, the gas feeding port 6a giving the high speed gasflow crossing by inclining in the progressing direction for the laser beam 1 is provided inside the work head 9a between the converging lens 2 and the body 5 to be machined and the exhaust port 8a exhausting the gasflow is provided at the downstream side of the high speed gasflow. The injection port 7a of the high speed gas is taken as a belt like opening part and the opening area of the gas exhaust port 8a is made larger than that of a laser beam fetching port 10a. The expulsion and evaporation bodies generated by welding are thus taken out from the exhaust port 8a to control the stain of the converging lens 2. |
