Workpiece feeding apparatus in seam welding machine

摘要

A wrist portion assembly for a workpiece feeding apparatus of a seam welding machine wherein a workpiece is supported through a chucking device on an operational end of a robot so that a portion of the workpiece to be welded is fed between a pair of upper and lower electrode rolls. The wrist portion includes plural turnable members. At least one of the turnable members which serves to move the chucking device upwardly and downwardly by the turning thereof is formed into an idle turnable member having no driving source.