ELECTRIC DRIVE Russian patent published in 2006 - IPC F16K31/05 

FIELD: pipeline engineering.

SUBSTANCE: electric drive comprises three-phase asynchronous motor with shortened rotor, transmitting mechanism, and optical-mechanical transducer for determining position of the output link of the transmitting mechanism. The electric drive has the torque unit made for permitting calculation of torque as a function of current in the stator of the asynchronous electric motor, speed of rotation of the rotor, and current frequency as well as for permitting control of limit torque. The first input of the unit is connected with the stator winding of the asynchronous electric motor through the current transducer. The second input of the unit is connected with the optical-mechanical pickup of position of the output link of the transmitting mechanism. The controller of the position of the outlet link has the first input for control of limit position, second input connected with the optical-mechanical pickup of position, and output. The electric drive is made for permitting determination of the speed of rotation of the asynchronous electric motor for torque unit from the readings of the optical-mechanical pickup of position.

EFFECT: simplified structure, reduced sizes, and enhanced reliability.

6 cl, 3 dwg