Patent ID: 7563188

Claim:
A conveyor chain comprising a number of chain links connected by hinge pins, each link including a plurality of hinge parts comprising finger members protruding in laterally-spaced relation from front end edges and rear end edges, adjacent ones of said links being connected to each other in the longitudinal direction of the chain through said hinge pin, and free ball elements which are free to rotate in any direction protruding from both the top surface and bottom surface of said chain, wherein each of said chain links has a body with U-shaped mounting regions forming ball-receiving channels having a base wall in the middle of the link and side walls extending longitudinally of the chain from the middle of the link through one of said front end edge and rear end edges to provide an open end for said channel in said one end edge, and a pair of ball-holding retainer elements rotatably sandwiching one of said free ball elements therebetween in one channel of one of said mounting regions of said chain links, said channel open end being closed by said hinge pin to capture the ball-holding retainer elements, and an exposed tool-inserting slot intercepting the base of each of said U-shaped mounting regions to enable the insertion of a tool to displace said ball-holding retainer along said side walls away from said base.