Abstract: There is a solenoid including a stator having a first stator tooth and a second stator tooth, and an armature having a first armature tooth and a second armature tooth. The armature is moveable with respect to the stator over a predetermined stroke. A coil is associated with one of the stator and the armature for conducting an electric current and generating magnetic flux that is guided by the stator and the armature. The stator or the armature acts as a ferromagnetic core for the coil. There is a first air-gap between the first stator tooth and the first armature tooth that has a first length, and a second air-gap between the second stator tooth and the second armature tooth that has a second length. The first and second lengths are constant to within a predetermined margin over the predetermined stroke when the first and second armature teeth overlap the first and second stator teeth respectively.

Abstract: There is a solenoid including a stator having a first stator tooth and a second stator tooth, and an armature having a first armature tooth and a second armature tooth. The armature is moveable with respect to the stator over a predetermined stroke. A coil is associated with one of the stator and the armature for conducting an electric current and generating magnetic flux that is guided by the stator and the armature. The stator or the armature acts as a ferromagnetic core for the coil. There is a first air-gap between the first stator tooth and the first armature tooth that has a first length, and a second air-gap between the second stator tooth and the second armature tooth that has a second length. The first and second lengths are constant to within a predetermined margin over the predetermined stroke when the first and second armature teeth overlap the first and second stator teeth respectively.

Abstract: Disclosed is a method and corresponding fuel injector for injecting gaseous and liquid fuel into an engine. The method comprises delivering a liquid fuel to a fuel injector, delivering a pressurized gaseous fuel to the fuel injector, entraining the liquid fuel within the gaseous fuel within a chamber of the fuel injector and injecting the gaseous fuel and atomized liquid fuel into the combustion chamber. The liquid fuel can be passed through and dispensed from a needle into a chamber in the injector nozzle where it is entrained in the gaseous fuel during an injection event. The liquid/gas mass ratio is controlled by the needle movement, hydraulic resistances or electronic valves so that the majority of the liquid is injected during the first part of the gas injection. The injector can be used for late cycle direct injection of natural gas, or any number of gaseous fuel blends combined with many liquid fuels such as diesel, biodiesel and DME.

Abstract: Disclosed is a method and corresponding fuel injector for injecting gaseous and liquid fuel into an engine. The method comprises delivering a liquid fuel to a fuel injector, delivering a pressurized gaseous fuel to the fuel injector, entraining the liquid fuel within the gaseous fuel within a chamber of the fuel injector and injecting the gaseous fuel and atomized liquid fuel into the combustion chamber. The liquid fuel can be passed through and dispensed from a needle into a chamber in the injector nozzle where it is entrained in the gaseous fuel during an injection event. The liquid/gas mass ratio is controlled by the needle movement, hydraulic resistances or electronic valves so that the majority of the liquid is injected during the first part of the gas injection. The injector can be used for late cycle direct injection of natural gas, or any number of gaseous fuel blends combined with many liquid fuels such as diesel, biodiesel and DME.

Abstract: A method and apparatus adjust pilot fuel injection timing in relation to a main fuel injection timing into a piston cylinder of an operating gaseous-fuelled direct injection internal combustion engine using high levels of EGR. A set of engine parameters are monitored which determine engine load and engine speed and an indicator of EGR concentration within the intake charge. Pilot fuel timing relative to main fuel injection timing is then adjusted according to the engine parameters. High levels of EGR are shown to be tolerated with relatively limited penalties in relation to other emissions typically found with high EGR by reducing the relative injection timing the pilot fuel as compared to main fuel injection timing.