Patent attributes
Nut runner system which includes holder table having tightening point at one end and coupling part at other end, and configured to hold plurality of bits, and nut runner main body including carrier coupled to wrist part of robotic arm, spindle supported by carrier, and bit changer coupled to spindle and which one of plurality of bits is attached. Coupling part of each of plurality of bits has an engaging hole coaxial with tightening point, and annular protrusion that continues in circumferential directions is formed in inner circumferential surface of engaging hole. Bit changer includes actuator, actuator made of engaging shaft to be inserted into engaging hole and operating pieces formed in engaging shaft, operating pieces moving between engaging position wherein operating pieces protrude radially outward from inner circumferential edge of annular protrusion and retracted position wherein operating pieces are retracted radially inward from inner circumferential edge of annular protrusion.
