Patent Number: 046474242
Section: abstract

A refueling machine (100) is provided with a latching/unlatching rod (116) which is provided with a hexagonally configured head portion for mated engagement with a hexagonally configured socket (34) defined within a latching/unlatching screw (22) of a fuel assembly (10) whereby the fuel assembly (10) may be securely mechanically connected to the lower core support plate of the reactor internals. The latching/unlatching rod (116) is fixedly connected to a housing (118) which is co-axially disposed within a torque tube (140), the latter of which is fixedly secured to the lower end of a spur gear (130). The spur gear (130) is rotatably engaged with a drive spur gear (148) through means of an idler gear (128), whereby torque is transmitted to the torque tube (140). The torque tube (140) has a square-shaped configuration in cross-section, and the housing (118) has similarly configured flanged portion (144, 146) for cooperation therewith whereby rotary torque is transmitted to the housing (118) and the latching/unlatching rod ( 116). The housing (118), latching/unlatching rod (116), and torque tube (140) are all co-axially disposed within the refueling machine gripper tube (108) and outer stationary mast (102), and a dual winch drive system (112, 124) is provided for independently controlling the vertical movements of the gripper tube (108) and latching/unlatching rod (116), respectively.