| 摘要 |
PURPOSE:To reduce a thermal effect and to obtain a specified depth of penetration by irradiating a butt part of plates with a laser beam condensed by a condenser lens and moving relatively the condenser lens with respect to the plates along a weld line of the butt part. CONSTITUTION:Laser beam welding is performed along the weld line WL at the butt part WC between a plate WA and a plate WB. In this case, the condenser lens 19 provided on the inside of a machining head 5 is moved in either one direction of the X-line direction or the Y direction. At the same time, the condenser lens 19 is reciprocated between the upper end position and the lower end position. As a result, a weld zone WS like a sine curve, for instance, is formed on the butt part WC. Accordingly, the weld zone WS exists along the weld line WL and the specified depth (h) of penetration can be obtained. |
