Patent ID: 6202688
Filing Date: 2001-03-20
Classification: F02M,F16K,F17C,Y02T,Y10T

Abstract:
A tank valve assembly with manual override for connection to a tank containing high pressure gaseous fuel, said valve assembly and manual override comprising in combination:(a) an inlet passageway and an outlet passageway;(b) in said valve assembly, a bleed valve and a main valve, said main valve having a secondary piston mounted to open and close a main orifice, said bleed valve having a bleed valve stem mounted to move relative to said secondary piston to open and close a bleed orifice, said main orifice and said bleed orifice providing access to said outlet passageway, an outer portion of said secondary piston being mounted in a zone that has an open access to said tank through said inlet passageway when both of said valves are closed so that said zone has a pressure substantially equal to a pressure of said high pressure gaseous fuel within said tank, said zone being isolated from said access to said tank when said bleed valve opens by a sufficient amount, said zone having a drain to drain pressure from said zone when said zone is isolated from said access, said secondary piston having an inner portion that is mounted in a chamber, said chamber being accessible to said high pressure gaseous fluid in said tank, said main valve opening when said pressure on said inner portion from said chamber is sufficiently greater than a pressure on said outer portion from said zone, said bleed valve being connected to open when a solenoid is activated, said main valve closing when said solenoid is deactivated, said secondary piston being biased towards a closed position by a force external to said secondary piston, said zone having said open access to said gaseous fuel within said tank when said bleed valve is closed, said main valve closing when said pressure in said zone on said outer portion is sufficiently greater than a pressure on said inner portion;(c) said manual override being connected to alternately close off said tank or vent said tank if said instant-on valve assembly is not operating properly,wherein the manual override has an elongated spindle with a head at an outer end thereof, said valve spindle having annular projections thereon, said annular projections being sized to fit within a corresponding screw thread in a housing surrounding said spindle so that said spindle will move inward when turned in one direction and outward when turned in an opposite direction, said manual override having a fully open position when said spindle is turned outward to allow gaseous fuel to flow to said valve assembly, said manual override having a fully closed position when said spindle is turned fully into an inlet passageway to said valve assembly to close said passageway, said manual override having a bypass position to permit gaseous fuel to flow from said tank directly into said outlet passageway, thereby bypassing said valve assembly.