Patent ID: 6484924
Filing Date: 2002-11-26
Classification: B23K

Abstract:
An apparatus for backing up a weld joint formed in a workpiece by a friction stir welding tool comprising:a backing ring, at least a portion of said backing ring engaging the weld joint opposite the friction stir welding tool such that said backing ring deforms to thereby define a contact zone that exerts a force against the weld joint, said force having a magnitude; a restraining member in operable communication with said backing ring; at least one sensor for measuring the magnitude of force exerted by said contact zone of said backing ring upon the weld joint; and means for moving said restraining member relative to the weld joint in order to modify the force exerted by said contact zone of said backing ring upon the weld joint, said moving means being responsive to said sensor and being in operable communication with said restraining member.