NUCLEAR REACTOR CONTROL-ROD DRIVE Russian patent published in 1994 - IPC

FIELD: nuclear power engineering. SUBSTANCE: nuclear reactor control-rod drive has electric motor 2 whose rotor 3 is kinematically linked through hollow shaft 4 with reduction unit 5. The latter imparts rotary motion to rack gear 6 while rotor 3 is revolving via hollow shaft 4. As a result rack 7 moves and functions as final element coupled with control element (not shown on drawing). Top end of rack 7 rolls within hollow shaft 4 on bearing 8. Rotation of hollow shaft 4 displaces shunt 10 in direction opposite to that of rack 7. In its displacement shut 10 induces emf in windings 11 with the result that permanent information about position of control element is available. EFFECT: reduced power requirement for drive motor of reactor safety system. 1 dwg