GASEOUS AND LIQUID FUEL INJECTION VALVE WITH CONCENTRIC NEEDLES

摘要

A gaseous and liquid fuel injection valve for an internal combustion engine comprises an injection valve body that houses two separate concentric fuel injection valve assemblies. The first valve assembly is a pilot fuel needle valve assembly, which comprises a first needle movable in the direction of the longitudinal axis of the body between an open and a closed position. The pilot fuel valve assembly controls the injection of pilot fuel into a combustion chamber of the engine through a plurality of pilot fuel holes formed in a nozzle tip of the pilot needle valve assembly. The second valve assembly is a gaseous fuel needle valve assembly, which comprises a second needle movable in the direction of the longitudinal axis between an open and a closed position. The gaseous fuel needle valve assembly controls the injection of gaseous fuel into the combustion chamber through a plurality of gaseous fuel holes formed in a nozzle tip of the gaseous fuel needle valve assembly. At least one of the nozzle tips is rotatable to thereby change the position of the pilot fuel holes with respect to the gaseous fuel holes. The number of the plurality of pilot fuel holes is different from the number of the plurality of gaseous fuel holes.