LASER WELDING METHOD AND LASER WELDING EQUIPMENT

摘要

PROBLEM TO BE SOLVED: To provide a laser welding method and laser welding equipment capable of discriminating a deviation of an irradiated position of a laser beam during welding despite a simple arrangement.SOLUTION: A laser welding method includes a laser beam irradiation process of sweeping a laser beam along a stepped part formed by abutment parts of workpieces having different thicknesses. The laser beam irradiation process includes a detection step of detecting an amount of light near an irradiated position of the laser beam on the stepped part using first optical detection means located on the side of the workpiece having a larger thickness, and second optical detection means located on the side of the workpiece having a smaller thickness; and a decision step of computing a mean value of an output value of the first optical detection means and an output value of the second optical detection means, and a standard deviation, and deciding on the basis of change quantities of the mean value and the standard deviation from reference values whether the irradiated position of the laser beam is deviated from the stepped part.