| 摘要 |
A high pressure gaseous fuel injector for injecting natural gas or other gaseous fuels at high pressures (eg.300 to 700 psig more or less) into combustion engines for improved efficiency, better performance and reduced environmental emissions. The fuel injector is powered by hydraulic signals from an electrohydraulic valve . The fuel injector includes an outer cartridge housing and a universal valve cartridge mounted therein. The cartridge comprises an activator body and a valve body secured together, and the valve body has a gas valve slidable therein. The stroke of the valve is adjustable by controlling the size of shims in the valve body assembly, thereby providing a universal valve cartridge that can be easily adapted to differin g fueling requirements for models and sizes of engines. The valve body includes a spri ng chamber between upper and lower valve guides. The valve body also includes cross-holes to allow cool gaseous fuel to successively pulsate into and out of the spring chamber and thereby cool the exposed portion of the valve between guides, preventing heating of the dynamic gas seal located in the upper guide. An unsealed smal l clearance between the actuating piston and its bore in the actuator body allows controlled leakage of oil. The leakage of oil lubricates metal to metal contact between the upper guide and the valve and lubricates the dynamic gas seal. Gaseous fuel leakage into the leaked oil is tolerated and any combined oil/gaseous fuel i s removed to an external location for separation. Spring washers are used to urge the valve assembly insert against a metal O-ring supported by the outer cartridge body . |
