Patent ID: 6315266
Filing Date: 2001-11-13
Classification: F16K,F25B

Abstract:
A pilot operated flow regulating valve including a main valve element arranged in a flow passage to which high-pressure fluid is supplied, a circular valve seat formed in said flow passage, said main valve element facing said valve seat,a pressure receiving member arranged with its front surface exposed to the fluid in said flow passage, said pressure receiving member being moveable in accordance with a differential pressure between a fluid pressure applied to said front surface in a first portion of said flow passage and a pressure in a pressure control chamber bounded by a rear surface of said pressure receiving member,a driving force transmitting member interposed between said pressure receiving member and said main valve element so as to move said pressure receiving member and said main valve element in directions such that said main valve element moves towards said valve seat into a first, completely seated position and away from said valve seat into other positions allowing a fluid flow through said valve seat,a pilot passage connecting said pressure control chamber with said second portion of said flow passage located at a side of said valve seat opposite to said pressure receiving member,a leak passage of small cross-sectional area permitting leak of fluid between said pressure control chamber and said first portion of said flow passage,urging means for urging said main valve element in a direction opposite to a driving direction of said pressure receiving member, anda pilot passage constant differential-pressure regulating valve which opens when a differential pressure between an inlet and an outlet of said pilot passage becomes higher than a given pressure in order to keep said differential pressure essentially constant, wherein in said other positions of said main valve element at least one of said urging means and said driving force transmitting member is forcing said main valve element into a vibration suppressing contact with only a portion of said circular valve seat.