Pressure/flow compensated direct acting pressure regulator

Abstract

A regulator valve includes a spring casing and a lower casing sandwiching a diaphragm. A cylindrical orifice tube defines an inlet and terminates short of an in-line outlet port. A one piece cam stem and relief seat is mounted for movement with the diaphragm and includes cam surfaces for directly engaging a movable disk holder. The disk holder moves in a straight line in the orifice tube and the cam surfaces move the holder at a non linear rate with respect to the diaphragm. The distal portion of the orifice tube houses a boost mechanism. A movable piston in the inlet side of the orifice tube has two pairs of spirally converging grooves on its inner surface for supporting a pair of flat gates that are rotated relative to each other to vary flow area when the piston moves responsive to differences between the inlet pressure and the pressure on the underside of the diaphragm. The distal end of the orifice tube includes an end cap and a movable deflector ring that has diametrically opposed ears projecting into cutout portions of the boost tube. The deflector ring is spring biased away from the end cap and includes flow apertures in its surface. Responsive to increased flow, the deflector is moved back against the pressure of the spring to open the cutout portions and enable flow to be diverted to the underside of the diaphragm.