Patent ID: 6418956
Filing Date: 2002-07-16
Classification: G05D,Y10T

Abstract:
A pressure controller apparatus for controlling a pressure regulator comprising:a housing including a control chamber and a diaphragm chamber; an inlet in the control chamber for receiving control pressure; an outlet from the control chamber to a pressure regulator; an inlet in the diaphragm chamber to sense process fluid pressure; a diaphragm moveable in the diaphragm chamber based on the process fluid pressure; a valve moveable by the diaphragm to open the control chamber to a drain; and bias means interconnected with the valve to bias the valve towards a closed position; wherein, when process fluid pressure is low, the valve moves toward a closed position to allow control pressure to flow through the control chamber to a pressure regulator to increase pressure on a pressure regulator, and when process fluid pressure is high, the valve moves towards an open position and control pressure flows from the control chamber to the drain.