Fuel assembly unlatching and handling gripper

A refueling machine is provided with a latching/unlatching rod which is provided with a hexagonally configured head portion for mated engagement with a hexagonally configured socket defined within a latching/unlatching screw of a fuel assembly whereby the fuel assembly may be securely mechanically connected to the lower core support plate of the reactor internals. The latching/unlatching rod is fixedly connected to a housing which is co-axially disposed within a torque tube, secured to the lower end of a spur gear rotatably engaged with a drive spur gear through means of an idler gear whereby torque is transmitted to the torque tube. The torque tube has a square-shaped configuration in cross-section, and the housing has similarly configured flanged portions for cooperation therewith whereby rotary torque is transmitted to the housing and the latching/unlatching rod. The housing latching/unlatching rod, and torque tube are all co-axially disposed within the refuelling machine gripper tube and outer stationary mast, and a dual winch drive system is provided for independently controlling the vertical movements of the gripper tube and latching/unlatching rod respectively. (author)