NUCLEAR REACTOR CONTROL ELEMENT DRIVE Russian patent published in 2003 - IPC

FIELD: devices for shifting control elements of pressurized-water reactors. SUBSTANCE: drive has casing, tractive, locking, and retaining electromagnets, toothed rod, movable and retaining latches connected to armatures, and pulling armature coupled with movable pole of locking electromagnet and with movable latch. Fixed pole of tractive electromagnet and that of retaining electromagnet are mounted on bearing pipe. Maximal sectional area of locking-electromagnet movable pole connected to armature when movable latch closes is disposed below top pole of locking electromagnet by minimum two motion pitches of tractive-electromagnet armature. Maximal sectional area of locking- electromagnet armature is disposed below bottom pole of locking electromagnet by minimum one motion pitch of tractive-electromagnet armature. Locking-electromagnet pole and armature when moving upward through one pitch function as solenoid jointly with tractive electromagnet. EFFECT: reduced dynamic force in drive operation; enhanced mass handled by control element. 2 cl, 6 dwg