FRICTION STIR SPOT WELDING APPARATUS, FRICTION STIR SPOT WELDING METHOD, AND PERPENDICULAR-TO-PLANE DETECTION DEVICE FOR USE IN FRICTION STIR SPOT WELDING

摘要

This friction stir spot welding apparatus is provided with a rotating tool (10A) and a perpendicularity detection unit (20A) for detecting whether or not the position of the rotating tool (10A) is perpendicular to the surface of the welding site of the object being welded (50). The perpendicularity detection unit (20A) measures the distance to at least three measurement positions set around the welding site with, for example, position sensors (21). Said measurement positions are set on a reference plane, which has the forward-reverse direction of the rotating tool (10A) as the direction of the normal vector, so as to be located at the vertices of a polygon. The perpendicularity detection unit (20A) determines that the rotating tool is in a perpendicular state when the distances to all of the measurement positions are equal.