Pneumatic pressure regulator - has double pilot control unit based upon diaphragm elements to provide precision control of main valve to regulate output

摘要

The precision pressure regulator has first (7) and second (15) pilot control stages for operation of the main stage (1). The main stage has an inlet (2) and outlet (3) with a poppet (4) moved by the pilot stage pin (5) to vary the control orifice. the pin is coupled to a diaphragm actuator (6). The second pilot stage hgas a diaphragm (17) that responds to the difference in force produced by the reference setting of a spring (19) and the output pressure. This determines the opening of a ball valve (20) admitting flow to the first pilot stage which also moves the open a valve to operate the main valve. ADVANTAGE - Double pilot valve provides high pressure accuracy.