Patent ID: 6254057
Filing Date: 2001-07-03
Classification: F16K,Y10T

Abstract:
A fluid control valve comprising:a) a body having an inlet, an outlet and a fluid path extending between the inlet and the outlet;b) a chamber in the body the chamber in fluid communication with a control port;c) a valve member movably disposed within the body for motion toward or away from a valve seat along a trajectory, the valve member having a closed position wherein the valve member is sealed against the valve seat and the fluid path is blocked by the valve member and an open position wherein the fluid path is not blocked by the valve member, the valve member movable toward the closed position along the trajectory by increasing a fluid pressure within the chamber;wherein, when the valve member is in an intermediate position between its open and closed positions, the fluid path extends through a first constriction zone between the body and a surface on the valve member which is oriented substantially parallel to the trajectory, through a stagnation zone between the body and a surface on the valve member which extends substantially transversely to the trajectory, and through a second constriction zone between the body and a surface on the valve member which is oriented substantially parallel to the trajectory, where the stagnation zone provides a cross-sectional area in the fluid path at least twice as large as a cross sectional area provided by the first constriction zone and at least twice as large as a cross sectional area provided by the second constriction zone.