ELECTRIC DRIVE OF LOCKING DEVICE Russian patent published in 2003 - IPC

FIELD: pipeline valves and fittings; controls of locking devices. SUBSTANCE: proposed electric drive contains transfer mechanism and electric motor unit. Electric motor unit consists of electric motor, gear train, two series-connected planetary gear trains with central wheel, and carrier with planet pinions. Central wheel of first gear train is braked by ball detent. Carrier of second gear train is rigidly coupled with output shaft of electric drive unit. Output shaft of electric drive unit is coupled transfer mechanism with rotary locking member. Transfer mechanism is essentially crankand-rocker mechanism with rotary locking member playing the part of rocker. Crank is rigidly coupled with output shaft of electric drive unit. Connecting rod features longitudinal resilience. Introduced stops are installed so that angle of turning of crank between stops exceeds its angle of turning between dead points of crank-and-rocker mechanism. Central wheel of first planetary gear train of electric drive unit is provided with two cams for interaction with electric motor disconnecting microswitches when crank thrusts against stop. Transfer mechanism is furnished with ball detent installed for engagement with crank thrusting against stops. EFFECT: improved accuracy and reliability of control in extreme positions of locking device. 3 cl, 3 dwg