Patent ID: 6832748
Filing Date: 2004-12-21
Classification: F16K

Abstract:
A valve for controlling the flow of fluid bi-directionally between an upstream supply and a downstream location, comprising:a valve body including a valve seat through which fluid may flow in both directions between the upstream supply and the downstream location, the valve body defining: a first chamber upstream of the valve seat; a second chamber in fluid communication with the first chamber; and a fluid flow path connecting the first chamber with the upstream supply, the fluid flow path having a predetermined upstream flow restriction; a valve assembly mounted in the valve body and moveable between a closed position and an open position, the valve assembly including a valve element with an enlarged portion positioned downstream of the valve seat that is adapted to engage the valve seat when the valve assembly is in the closed position, the valve assembly in communication with the fluid pressure within the first chamber, the second chamber, the downstream location and the upstream location such that the forces exerted upon the valve assembly by the fluid pressure bias the valve assembly to the open position when the fluid flows from the downstream location to the upstream supply; wherein the valve assembly further includes a spacer with an annular cavity on a lower surface which is in fluid communication with the upstream supply.