Patent ID: 8792605

Claim:
An unlatching tool for extracting a control rod from a support casting of a nuclear reactor, comprising: a baseplate; at least one guide member vertically extending below the baseplate; a frame attached to the baseplate; a rotatable cable reel shaft connected to the frame; a worm drive configured to rotate the cable reel shaft; a stepper motor configured to power the worm drive; a hose wrapped around the cable reel shaft, the cable reel shaft being configured to lower a distal end of the hose below the baseplate and the guide member; and a hook attached to the distal end of the hose, the hook including a vertically-oriented cylindrical sleeve with more than one foldable finger, the foldable fingers having a retracted position where each of the fingers is held in a vertically-oriented position within the cylindrical sleeve, and an extended position where each of the fingers is horizontally extended from the cylindrical sleeve at different axial elevations from each other.