Patent ID: 6777902
Filing Date: 2004-08-17
Classification: E05Y,H02P

Abstract:
A motor for driving a movable barrier operator, said motor comprising:a rotor capable of rotating in a first and a second direction; a stator, said stator comprising a first winding and a second winding, said first winding and second winding connected at one end to a neutral motor terminal; a first capacitor coupled across winding terminals at an other end of each of said first winding and said second winding; a direction control selectively passing alternating current (AC) to either side of said first capacitor to selectively rotate the rotor in the first or the second direction; a second capacitor selectively coupled across said first capacitor when AC is provided to one side of said first capacitor and disconnected from said first capacitor when AC is provided to a second side of said first capacitor to control the amount of power delivered by the motor; an apparatus for sensing motor speed; and a controller responsive to the sensed motor speed for controlling the selective coupling of the second capacitor.