Abstract: A system for estimating a quantity of parasitic leakage of a fluid from a fluid collection unit includes a pressure sensor and a control circuit. The pressure sensor is coupled to the fluid collection unit and configured to produce a pressure value indicative of the pressure of the fluid collection unit. The control circuit is operable to determine a change in pressure value of the fluid collection unit and estimate the quantity of parasitic leakage based on the change in pressure value. The control circuit may also be operable to determine a bulk modulus value of the fluid and estimate the quantity of parasitic leakage based on the change in pressure value and the bulk modulus value.

Abstract: The valve includes a valve element with an internal longitudinal bore and cross-drilled orifices which, in combination with other orifices and restrictions, force balance the valve in an open configuration when attached to a pump assembly in a spilling mode.

Abstract: A system for estimating an auxiliary-injected fuel quantity includes a fuel injector for injecting fuel into an engine, a fuel pump supplying fuel to a fuel collection unit that then supplies fuel to the fuel injector, and a control circuit that generates an auxiliary-injected fuel quantity estimation model by disabling the fuel pump prior to fuel injection, and enabling the fuel pump to resume fuel pumping following fuel injection, by the fuel injector, determines a first pressure in the fuel collection unit after stabilization of the fuel pressure therein following disablement of the fuel pump and prior to the fuel injection, determines a second pressure in the fuel collection unit after the fuel injection and prior to resuming pumping of fuel by the fuel pump, and forms the model as a function of the first and second pressures and an injector on-time for a number of different engine operating conditions.

Abstract: A system for estimating a quantity of parasitic leakage of a fluid from a fluid collection unit includes a pressure sensor and a control circuit. The pressure sensor is coupled to the fluid collection unit and configured to produce a pressure value indicative of the pressure of the fluid collection unit. The control circuit is operable to determine a change in pressure value of the fluid collection unit and estimate the quantity of parasitic leakage based on the change in pressure value. The control circuit may also be operable to determine a bulk modulus value of the fluid and estimate the quantity of parasitic leakage based on the change in pressure value and the bulk modulus value.

Abstract: A variable pressure fuel injection system and multi-flow rate injector is provided which produces multiple fuel injection flow rates from a common source of pressurized fuel to enable reductions in emissions, combustion noise and particulates while improving fuel consumption. The present invention includes inner and outer needle valve elements biased into respective closed positions against respective valve seats for controlling the flow through corresponding sets of injection orifices. The movement of each valve is controlled by an injection control valve controlling the drain flow of control fuel from respective control volumes positioned at outer ends of the valve elements. Valve element bias spring preloads along with control flow orifices and needle valve element surface areas are selected to cause, for example, single valve operation at low fuel supply pressure and dual valve operation at high supply pressure.

Abstract: A system for estimating an auxiliary-injected fuel quantity includes a fuel injector for injecting fuel into an engine, a fuel pump supplying fuel to a fuel collection unit that then supplies fuel to the fuel injector, and a control circuit that generates an auxiliary-injected fuel quantity estimation model by disabling the fuel pump prior to fuel injection, and enabling the fuel pump to resume fuel pumping following fuel injection, by the fuel injector, determines a first pressure in the fuel collection unit after stabilization of the fuel pressure therein following disablement of the fuel pump and prior to the fuel injection, determines a second pressure in the fuel collection unit after the fuel injection and prior to resuming pumping of fuel by the fuel pump, and forms the model as a function of the first and second pressures and an injector on-time for a number of different engine operating conditions.

Abstract: A closed needle injector assembly is provided which effectively permits low fueling quantity control in short duration injections and pilot quantity control in longer duration events without compromising energy efficiency, maximum fuel delivery rates nor requiring increased operating pressures. The closed needle injector assembly includes first and second needle valve elements and a throttle passage formed in the second needle valve element to restrict fuel flow through an injector orifice. The second needle valve element is telescopingly received within the first needle valve element. Respective control volumes and one or more injection control valves are used to control the movement of the needle valve elements. Operation of the assembly results in movement of the first needle valve element to an open position for throttling fuel flow through the throttle passage followed by subsequent lifting of the second needle valve element for longer duration injections.

Abstract: The high-pressure fluid manifold connection assembly includes a one-piece tube collar with an annular relief cavity that surrounds a high-pressure fluid tube. The tube includes a hole that passes through the tube and which is not aligned with an exit hole in an annular relief cavity of the tube collar.

Abstract: The valve includes a valve element with an internal longitudinal bore and cross-drilled orifices which, in combination with other orifices and restrictions, force balance the valve in an open configuration when attached to a pump assembly in a spilling mode.

Abstract: A closed needle injector assembly and method are provided which effectively extending injection duration and improving fueling accuracy at part load conditions, providing a low quantity detached pilot injection at all operating conditions and controlling the duration of, and dwell time between, the pilot injection and one or more higher flow rate primary injections independent of fuel injection pressure. The closed needle injector assembly includes first and second needle valve elements, respective control volumes and a single injection control valve to control the movement of the needle valve elements. A sequencing device is mounted on the injector to permit movement of only the inner needle valve element to define a low fuel injection rate event and permit selectively, controlled movement of both the inner and outer needle valve elements to open positions to define a subsequent primary fuel injection event.

Abstract: A fuel control system for an internal combustion engine including injected fuel quantity estimation includes a fuel pump responsive to a fuel pump command to supply fuel to a fuel collection unit. A pressure sensor is provided for producing a pressure signal indicative of the pressure of fuel within the collection unit throughout a fuel injection event, and an engine position sensor is provided for producing an engine position signal indicative of a crank angle of the engine relative to a reference crank angle. A control circuit includes means responsive to the pressure signal and a desired fueling value for producing an initial fueling command, and further includes a fuel quantity estimation block responsive to the pressure signal, the engine position signal and a final fueling command to produce a fuel quantity estimation value.

Abstract: An improved closed nozzle injector assembly for injecting high pressure fuel into the combustion chamber of an engine is provided which includes a first needle valve element associated with a first set of injector orifices, a first needle valve control device for controlling the opening and closing of the first needle valve, a second needle valve associated with a second set of injector orifices and a second needle valve control device for controlling the opening and closing of the second needle valve. Each needle valve control device includes a control volume positioned at one end of the respective needle valve, a control volume charge circuit for supplying high pressure fuel to the respective control volume and the respective injection control valve for controlling the flow of high pressure fuel from the respective control volume to a low pressure drain thereby controlling the movement of the respective needle valve.

Abstract: A fuel injection system is disclosed for an internal combustion engine that has multiple combustion chambers and a camshaft which cyclically imparts pressurization energy to and recovers pressurization energy from fuel being supplied to the engine. The fuel injection system includes a plurality of unit injectors, a camshaft linkage which simultaneously reciprocates pressurizing plungers of a set of at least two unit injectors and an interconnecting line which allows selective fluid interconnection between fuel pressurization chambers formed within the unit injectors. The interconnection line allows fluid linkage of the volume of fuel which is simultaneously pressurized and depressurized within the interconnected fuel pressurization chambers of a first set of unit injectors.

Abstract: A variable pressure fuel injection system and multi-flow rate injector is provided which produces multiple fuel injection flow rates from a common source of pressurized fuel to enable reductions in emissions, combustion noise and particulates while improving fuel consumption. The present invention includes inner and outer needle valve elements biased into respective closed positions against respective valve seats for controlling the flow through corresponding sets of injection orifices. The movement of each valve is controlled by an injection control valve controlling the drain flow of control fuel from respective control volumes positioned at outer ends of the valve elements. Valve element bias spring preloads along with control flow orifices and needle valve element surface areas are selected to cause, for example, single valve operation at low fuel supply pressure and dual valve operation at high supply pressure.

Abstract: A closed needle injector assembly and method are provided which effectively extending injection duration and improving fueling accuracy at part load conditions, providing a low quantity detached pilot injection at all operating conditions and controlling the duration of, and dwell time between, the pilot injection and one or more higher flow rate primary injections independent of fuel injection pressure. The closed needle injector assembly includes first and second needle valve elements, respective control volumes and a single injection control valve to control the movement of the needle valve elements. A sequencing device is mounted on the injector to permit movement of only the inner needle valve element to define a low fuel injection rate event and permit selectively, controlled movement of both the inner and outer needle valve elements to open positions to define a subsequent primary fuel injection event.

Abstract: A closed needle injector assembly and method are provided which effectively permits low fueling quantity control in short duration injections and pilot quantity control in longer duration events without compromising energy efficiency, maximum fuel delivery rates nor requiring increased operating pressures. The closed needle injector assembly includes first and second needle valve elements and a throttle passage formed in the second needle valve element to restrict fuel flow through an injector orifice. The second needle valve element is telescopingly received within the first needle valve element. Respective control volumes and one or more injection control valves are used to control the movement of the needle valve elements. Operation of the assembly results in movement of the first needle valve element to an open position for throttling fuel flow through the throttle passage followed by subsequent lifting of the second needle valve element for longer duration injections.

Abstract: A fuel injection pressure control system includes a control strategy operable to measure or estimate actual fuel injection pressure and control the operation of a fuel supply pump to thereby quickly and accurately control fuel injection pressure. The control strategy includes a closed-loop control strategy operable to compensate for instantaneous changes in system non-linearities, including fuel pump non-linearities and the like, and an open-loop control strategy operable to compensate for all system variations as well as system non-linearities, including between-engine variations in system operating parameters and other noise factors including deteriorating conditions, changes in environment and the like. Each strategy includes an adaptive controller operable to update one or more control parameters to thereby guarantee closed-loop stability, provide for fast and accurate system response during transient events, and minimize overshoots and undershoots.

Abstract: The high-pressure fluid manifold connection assembly includes a one-piece tube collar with an annular relief cavity that surrounds a high-pressure fluid tube. The tube includes a hole that passes through the tube and which is not aligned with an exit hole in an annular relief cavity of the tube collar.

Abstract: An improved closed nozzle injector assembly for injecting high pressure fuel into the combustion chamber of an engine is provided which includes a first needle valve element associated with a first set of injector orifices, a first needle valve control device for controlling the opening and closing of the first needle valve, a second needle valve associated with a second set of injector orifices and a second needle valve control device for controlling the opening and closing of the second needle valve. Each needle valve control device includes a control volume positioned at one end of the respective needle valve, a control volume charge circuit for supplying high pressure fuel to the respective control volume and the respective injection control valve for controlling the flow of high pressure fuel from the respective control volume to a low pressure drain thereby controlling the movement of the respective needle valve.

Abstract: An improved fuel injection system is provided which incorporates a common rail and a plurality of unit injectors which function together to efficiently produce various injection rate shapes and different combinations of discreet and blended pilot, main, post and after treatment fuel injection events during a single injection. The fuel injection system effectively permits flexible, responsively timed, square shaped, discreet low to mid pressure level injections utilizing the fuel pressure of the common rail while also allowing the unit injector portion to function independently to produce flexible and responsively timed and pressure controlled, triangular shaped high pressure fuel injection events and to recover excess energy. In one embodiment, a separate common rail pump is avoided by utilizing the unit injector plunger to replace fuel into the common rail which was previously injected.