Patent ID: 7766041
Filing Date: 2010-08-03
Classification: F16K,Y10T

Abstract:
1. A fluid flow control valve for regulating fluid communication, comprising: a cage having a longitudinal axis and apertures therein including at least a first and second axially spaced apart ports located in a wall thereof; a spool in said cage and configured to the interior shape of said cage, said spool having a sealing edge thereon and mounted for reciprocation within said cage between a first and second position along the longitudinal axis, the spool including at least a first and second axially spaced apart ports; at least a central port in said cage to permit fluid communication against at least one operative terminal end of said spool; an actuator coupled to said spool for effecting reciprocation thereof between said first position and said second position; the first and second ports in said spool positioned so that when said spool is in said first position fluid communication between said first and central ports is inhibited and when in said second position fluid communication between said first and central ports is allowed; and at least a pair of incremental pressure drop passages including a groove being located in a plane substantially perpendicular to the longitudinal axis of the spool for allowing incremental flow of fluid between said first and second ports prior to registry of the port in the spool with the first port in the cage as said spool is moving between said first and second positions, the groove being located in the spool and in a plane axially offset from the first and second ports of the spool.