Abstract: A low inertia transfer arm for rapid operation and for manipulation of small or medium sized parts comprises a supporting arm adapted for connection at one end to a device for movement of said arm having at least two degrees of freedom, a pair of tongs comprising a pair of jaws for gripping a part and mounted at the other end of said supporting arm, one of said jaws being rigidly attached to said supporting arm and the other of said jaws being movable relative thereto between open and closed relative positions of said jaws, and means for controlling opening and closing of said jaws, said controlling means including a rocker lever comprising a pair of arms for movement between two stable positions by contact between a respective one of said arms and a fixed stop, a torsion bar extending along said support arm fixed at one end to said movable tong jaw and at the other end to said rocker lever for rotation therewith about its longitudinal axis to cause opening and closing of said jaws.

Abstract: A device for causing a horizontal to-and-fro motion and a vertical up-and-down motion of a transfer arm comprising a member for driving the transfer arm and to be connected thereto which is moved up-and-down by a vertical cam rotating about a horizontal axis and to-and-fro by a horizontal cam rotating about a vertical axis, a return assembly being provided for returning the driving member against the action of the cams.