| 摘要 |
PURPOSE:To prevent a defective penetration bead and the generation of a burn through even in the case of the material to be welded having different thicknesses and of a laser bean coming out of a weld line with the minimum equipment by weaving a beam focus by a butt line in a laser butt welding method. CONSTITUTION:Each end part of the preceding steel strip 2 and succeeding steelstrip 3 is abutted each other a laser beam 4 is projected on the butt groove thereof, each end part is melted and a but welding is performed. The laser beam 4 is emitted from a laser oscillator 5a, reflected by a reflection mirror 5, condensed by a lens 6 and the focus 4a is abutted to the butt groove. In this case, the laser beam 4, especially the focus 4a is subjected to a weaving on the butt groove and travelled in the plate width direction to perform the welding. The back face of the mirror 5 is attracted alternately by turning ON or OFF electromagnets 7, 8 alternately, for instance, and the weaving is performed by rotating the mirror centering around its center 5'. With this method, a large-sized and complicated equipment is made unnecessary for cutting, butt, etc. |
