US Patent 7784324 Workpiece gripper arrangement for automatic tool change operations

A workpiece gripper arrangement for the automatization of presses, including a transfer arrangement for transferring components between workstations, the transfer arrangement includes a girder or carrier with gripper means for holding the components and the gripper means is supported via coupling parts of which one is connected to the girder and the other to the gripper means and a mechanical locking structure is provided which is operable by relative movement of the coupling arrangement with respect to a support frame on which the gripper means can be deposited.