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

A friction stir spot welding apparatus according to the present inventionincludes: arotary tool (10A); and a perpendicular-to-plane detector (20A), which detectswhether or not therotary tool (10A) is positioned to be in a perpendicular-to-plane staterelative to a joining targetportion of workpieces (50). The perpendicular-to-plane detector (20A) measuresdistances to atleast three measurement positions set around the joining target portion bymeans of, for example,position sensors (21). The measurement positions are set to be positioned atthe vertices of apolygon on a reference plane to which forward and backward movement directionsof the rotarytool (10A) are normal. The perpendicular-to-plane detector (20A) detects thatthe rotary tool(10A) is positioned to be in the perpendicular-to-plane state relative to thejoining target portionof the workpieces (50) if all the distances to the measurement positions areequal to each other.