Patent ID: 6422127
Filing Date: 2002-07-23
Classification: B62D,E05F,E05Y,F15B,F16K,Y10T

Abstract:
A two-stage pressurizing valve which comprises:a housing which defines a bore; an outlet passage which communicates with said bore at a first seat; an inlet passage which communicates with said bore at a second seat, said second seat having a smaller cross section than said bore; and a control passage for pressure medium, a valve element movable in said bore to open and close said first and second seats, said valve element having a first end shaped as a cone which is capable of seating on said second seat to block said inlet passage, a bias means for assisting pressure medium from said control passage in moving said valve element such that said cone-shaped first end seats on said second seat and blocks said inlet passage, and a piston which is movable against a second end of said valve element to prevent movement thereof away from said second valve seat, said piston being movable by pressure medium from said control passage.