Abstract: A system for effecting and controlling the movement of a window covering between different positions. In particular, the present invention includes a motor coupled to a window covering by way of a drive assembly. The drive assembly includes one or more hollow shafts, a drive shaft, and a torque sensing mechanism. The drive shaft is coupled between the motor and a hollow, sliding shaft by way of the torque sensing mechanism. Rotation of the motor causes a lift cord to wind or unwind from the hollow sliding shaft wherein the frictional engagement of the lift cord against the hollow, sliding shaft causes the shaft to slide. Additionally, the present invention includes a method for detecting and responding to disturbances in force sensing devices coupled to the lift cord.

Abstract: The present Invention comprises a novel and improved system for effecting and controlling the movement of a member between different positions, by way of example only, for opening and closing window shades. In particular, and without limitation, the Invention comprises a novel method to recognize and respond to obstructions in applications for motorizing lift products, as well as to provide touch control of the lift system.