Patent ID: 6457696
Filing Date: 2002-10-01
Classification: G05D

Abstract:
A pilot operated flow regulating valve, comprising:a main valve member arranged in the vicinity of a valve seat such that a closed state occurs when the mail valve member at the valve seat formed in a passage supplying high pressure fluid is contacted by the high pressure fluid from an upstream side; a pressure governing chamber formed as a branch from a passage at a downstream side of the valve seat; a pressure receiving member movably provided within the pressure governing chamber and coupled with the main valve member into one united body by a coupling member such that the pressure receiving member moves together with and actuates the main valve member into one united body by a coupling member such that the pressure receiving member moves together with and actuates the main valve member by receiving on a front surface and a rear surface a pressure present at the downstream side of the valve seat and a pressure inside the pressure governing chamber; a leak route having a small cross-section extending between the inside of the passage at the downstream side of the valve seat and an inside surface of the pressure governing chamber; a pilot route communicating with the upstream side of the valve seat to the inside surface of the pressure governing chamber; and a constant differential pressure control valve within the pilot route for maintaining a differential pressure constant between an inlet and an outlet of the pilot route by opening when the differential pressure excuses a certain value.