Abstract: A fuel injector is provided that includes various precise configuration parameters, including dimensions, shape and/or relative positioning of fuel injector features, resulting in improved efficiency of fuel flow through the fuel injector.

Abstract: A fuel injector is provided that creates variable spray characteristics to effectively reduce emissions, such as NOx emissions and particulate matter. The injector includes a nozzle valve element of the outwardly opening type including a fuel delivery passage and spray holes. The nozzle valve element is operable to move to a low lift position to cause fuel flowing from the spray holes to impinge on the injector body and to deflect toward the combustion chamber, and to move to a high lift position to cause fuel flowing from the spray holes to avoid impingement on injector body and flow in an obstructed manner directly into the combustion chamber. An annular chamber may be formed in the nozzle valve element adjacent the spray holes to receive fuel.

Abstract: A fuel injector is provided that creates variable spray characteristics to effectively reduce emissions, such as NOx emissions and particulate matter. The injector includes a nozzle valve element of the outwardly opening type including a fuel delivery passage and spray holes. The nozzle valve element is operable to move to a low lift position to cause fuel flowing from the spray holes to impinge on the injector body and to deflect toward the combustion chamber, and to move to a high lift position to cause fuel flowing from the spray holes to avoid impingement on injector body and flow in an obstructed manner directly into the combustion chamber. An annular chamber may be formed in the nozzle valve element adjacent the spray holes to receive fuel.

Abstract: A closed nozzle fuel injector is provided which effectively controls the fuel injection flow rate, especially during an initial portion of an injection event, while also permitting accurate control over pilot and/or post injection flow rates at all operating conditions thereby advantageously reducing emissions and combustion noise. The injector includes a rate shaping orifice to restrict fuel flow during an initial portion of an injection event and a rate shaping sleeve mounted for movement to cause a greater flow of injection fuel during a later portion of the injection event. A damping chamber and orifice are also provided to control movement of the rate shaping sleeve.

Abstract: A piezoelectric fuel injection system and a method of controlling same are provided which include a piezoelectric fuel injector having a piezoelectric element, a power source adapted to provide power to the piezoelectric element to actuate the piezoelectric fuel injector, and a controller adapted to charge the piezoelectric element to an initial voltage to begin said injection event, to decrease the voltage from the initial voltage to an intermediate voltage, and to increase the voltage from the intermediate voltage to a primary voltage to thereby control the injection rate shape. The initial voltage level is at least approximately equal to said primary voltage level and preferably approximately equal to a maximum voltage rating. The initial voltage duration, the intermediate voltage duration and the magnitude of the intermediate voltage can be changed or varied to modify the injection or rate shape.

Abstract: A preferred embodiment EGR valve permits exhaust gas to be induced into the intake line downstream of the compressor, while minimizing the need to reduce the size of the turbocharger. The preferred embodiment EGR valve exploits variations around the mean pressure in the EGR passage created by the engine cycle by selectively opening when the pressure in the EGR valve exceeds the pressure in the intake line. Thus, exhaust gas is recirculated even when the engine is running near torque peak. The preferred embodiment EGR valve also exploits the higher mean pressure in the exhaust line relative to the intake line at higher engine speeds by remaining open, in order to minimize the energy consumed in opening and closing the EGR valve.

Abstract: The fuel injector includes a solid state actuator that operates through an actuator motion amplifying lever to directly control the needle valve motion. Hydraulic forces, which act along the axes of the needle valve and the motion amplifying lever, are compensated by using a control piston, or other biasing means, to reduce the required amplitude of the control current/voltage and to reduce the required strength of the spring biasing the needle valve closed. The fuel injector may also include a control fuel inlet that is separate from the injection fuel inlet port.

Abstract: The fuel injector includes a solid state actuator that operates through an actuator motion amplifying lever to directly control the needle valve motion. Hydraulic forces, which act along the axes of the needle valve and the motion amplifying lever, are compensated by using a control piston, or other biasing means, to reduce the required amplitude of the control current/voltage and to reduce the required strength of the spring biasing the needle valve closed. The fuel injector may also include a control fuel inlet that is separate from the injection fuel inlet port.