CAPACITIVE ENERGY SOURCE FOR DAMPER AND ACTUATOR MOTORS

摘要

An emergency, fail safe capacitive energy source and circuit is used with an air damper (12) or valve (30) actuator. In particular, the capacitive source (68) and circuit (64) powers a motor (10) and both the motor as well as the capacitive source and circuit are completely contained within an actuator container (12, 30) of a small size. The capacitive source and circuit includes at least one storage capacitor (C4) utilized wherein the capacitor is coupled in series or parallel to power the motor (10). The capacitive source and circuit also includes a charging circuit (66) coupled between the motor drive power source (56) and the capacitor (68). A sensor (74) is coupled to the motor drive power source (50, 52, 54) and generates a control signal in the absence of power from the motor source. A switch (K1) passes power from the motor source (56) to the motor (10) in the absence of the control signal from the sensor and passes power from the capacitor in the presence of the control signal.