Patent ID: 9000327
Filing Date: 2015-04-07
Classification: B23K

Abstract:
1. A laser welding method comprising: controlling a focal point of a laser beam outputted from a laser oscillator to selectively focus the laser beam on a surface of a workpiece; moving a laser irradiation position at which the laser beam strikes on the surface of the workpiece; and selectively switching between a welding state and a non-welding state by changing a distance between the focal point and where the laser beam strikes the surface of the workpiece such that in the welding state the focal point is aligned with respect to the surface of the workpiece and such that in the non-welding state the focal point is positioned away from the surface of the workpiece while continuously outputting the laser beam from the laser oscillator before and after the switching between the welding state and the non-welding state, the selectively switching between the welding state and the non-welding state further including switching to the welding state by starting to increase a laser output power of the laser oscillator from a low power level toward a power level required for welding at a prescribed amount of time before the laser irradiation position reaches a welding start point, and starting to align the focal point with respect to the surface of the workpiece at the welding start point.