High Flow Capacity Positioner

A valve positioner for controlling an actuator to regulate fluid flowing within a fluid circuit, the valve positioner comprising:

• a positioner housing having a plurality of fluid flow passageways disposed therein;
• a positioner microprocessor disposed within the positioner housing, the positioner microprocessor being configured to receive an input signal representative of an actuator position;
• a spool manifold assembly disposed within the positioner housing adjacent the fluid flow passageways, the spool manifold assembly having a reciprocally moveable spool configured to selectively port fluid flow from the fluid flow passageways to the actuator;
• a diaphragm operatively coupled connected to the spool and configured to displace the spool in accordance with a pressure level exerted on the diaphragm;
• a flexible shaft connected to and extending between the spool and the diaphragm;
• a transducer in fluid communication with the diaphragm, the transducer being in electrical communication with the positioner microprocessor, the transducer configured to receive a pneumatic signal which is operative to regulate the fluid supplied to the diaphragm for displacing the spool.

A method for regulating fluid flowing within a fluid circuit, the method comprising the steps of:

• a. receiving an input signal on a positioner microprocessor disposed within a positioner, the positioner including a positioner housing having a plurality of fluid flow passageways, a spool manifold assembly disposed within the positioner housing, the spool manifold assembly having a spool for selectively porting fluid flow from the fluid flow passageways to an actuator;
• b. comparing the input signal to a position of the actuator and generating an electrical signal;
• c. transmitting the electrical signal from the positioner microprocessor to a transducer disposed within the positioner housing;
• d. supplying a diaphragm with fluid from the transducer, the diaphragm being mechanically connected to the spool;
• e. displacing the spool relative to the positioner housing for regulating the fluid flow to the actuator in response to a change in pressure associated with the diaphragm;
• f. generating a feedback signal representative of a pressure differential within the actuator using a feedback mechanism coupled to the actuator, the feedback mechanism being in electrical communication with the positioner microprocessor, the positioner microprocessor being configured to process the feedback signal;
• and
• g. repeating steps (b)-(f) until the actuator position corresponds to the received input signal.