METHOD FOR DETECTING STEM FORCE OF MOTOR DRIVING VALVE USING STEM FORCE DETECTING SENSOR AND APPARATUS THEREOF

摘要

PURPOSE: A method for detecting a stem force of a motor driving valve using a stem force detecting sensor and an apparatus thereof are provided to detect stem forces of opening and closing strokes without fixing a sensor inside a stem. CONSTITUTION: An up-motor-torque generated in an opening stroke of a motor driving valve is measured(S10). A force applied to a stem is measured when the stem ascends(S20). The efficiency of a driving part lifting the stem is obtained from the up-stem-force and the up-motor-torque(S30). An up-stem-force during opening of the valve is calculated by multiplying the up-motor-torque by the efficiency of the driving part(S40). A down-motor-torque generated in a closing stroke of the motor driving valve is measured(S50). A force applied to the stem is measured when the stem descends(S60). The efficiency of the driving part descending the stem is obtained from the down-stem-force and the down-motor-torque(S70). A down-stem-force during closing of the valve is calculated by multiplying the down-motor-torque by the efficiency of the driving part(S80).