Patent ID: 7993572

Claim:
An operation control method for a screw conveyor which includes an object supporting unit having a supporting portion for supporting an object to be conveyed, at least from a lower side of the object, a horizontally extending screw having a screw shaft and a screw blade provided around the screw shaft, and disposed such that the screw blade is located near the supporting portion of the object supporting unit, and an electric motor as a driver unit for moving the object to be conveyed in a direction parallel to the screw shaft by rotation of the screw blade of the screw, and which has a screw lift-up space above the screw disposed near the supporting portion, the method comprising the steps of: measuring the torque or an electric current value of the electric motor as a value corresponding to the load on the driver unit; and lifting up the screw shaft to the screw lift-up space when the load, determined according to the step of measuring the torque or an electric current value of the electric motor, reaches a previously set upper limit value, so as to increase a gap between an edge of the screw blade of the screw and the supporting portion of the object supporting unit.