Abstract: A fuel injection system for a gas trubine engine combustion chamber comprises at least one pilot fuel injector having a fuel discharge passage communicated to the combustion chamber and at least one secondary fuel injector having a fuel discharge passage communicated to the combustion chamber and a fuel purging passage communicated to a higher pressure region upstream of the combustion chamber. A fuel flow control device supplies metered fuel flow to the pilot fuel injector under all regimes of engine operation and to the secondary fuel injector under certain, intermittent regimes of engine operation requiring fuel flow above a selected level. A shuttle valve is movable to a first position to provide fuel flow communication between the fuel control device and the fuel discharge passage of the secondary fuel injector for fuel injection to the combustion chamber.

Abstract: A fuel injection system for a gas turbine engine combustion chamber comprises at least one pilot fuel injector having a fuel discharge passage communicated to the combustion chamber and at least one secondary fuel injector having a fuel discharge passage communicated to the combustion chamber and a fuel purging passage communicated to a higher pressure region upstream of the combustion chamber. A fuel flow control device supplies metered fuel flow to the pilot fuel injector under all regimes of engine operation and to the secondary fuel injector under certain, intermittent regimes of engine operation requiring fuel flow above a selected level. A shuttle valve is movable to a first position to provide fuel flow communication between the fuel control device and the fuel discharge passage of the secondary fuel injector for fuel injection to the combustion chamber.

Abstract: For application in controlling fuel flow to a gas turbine engine, the control valve includes one or more fuel inlet manifolds, a fuel outlet manifold and a fuel drain manifold in fuel flow relation with a longitudinal bore in a valve sleeve. A hollow spool valve is slidably disposed in the sleeve bore and includes a metering valve thereon movable past a fuel inlet aperture to meter fuel flow from the fuel inlet manifold to the fuel outlet manifold. The spool valve also includes a shut-off valve thereon for terminating fuel flow to the fuel outlet manifold under certain conditions. The hollow spool valve includes a longitudinal bore in fuel flow relation with the fuel outlet manifold and fuel drain manifold and a drain valve in the spool bore openable when fuel flow to the fuel outlet manifold is interrupted by the shut-off valve so that fuel can drain from the fuel outlet manifold to the drain manifold and closeable during metered fuel flow to the fluid outlet manifold.

Abstract: An ignition advance timing system for generating the ignition signal or the injection signal in an engine utilizes both the advantages of an angular-based system and a time-based system. A tooth wheel (10) operatively connected to the crankshaft of the engine (26) having groups (14) of teeth (16, 22, 24) positioned thereon. Each group represents the angular range of ignition or injection for a particular cylinder. The angular space (29) between each group of teeth allows a microprocessor (12) to begin a computing period (36) free of any interrupt signals generated by the teeth in the wheel. The microprocessor determines the desired angle which is synchronized with the teeth in the wheel to find the closest advance angle and by means of a timer the desired angle is generated.

Abstract: An apparatus and method for supplying a predetermined volume of liquid fuel (20) to a cylinder of a diesel engine (10) is provided. A storage tank (22) stores a column of the liquid fuel (20) in a storage area (24). A position sensor (36) transmits an analog signal proportional to the height of the fuel (20) in the tank (22). A pressure transducer (32) disposed at the bottom of the storage area (24) transmits an analog signal corresponding to the static fluid pressure at the bottom of the storage area (24). A temperature transducer (56) disposed along a fuel rail (16) transmits an analog temperature signal to an electronic fuel injection computer (14). The computer (14) converts the analog height signal, the analog temperature signal and the analog pressure signal into digital values and mathematically divides the resulting digital values of height and pressure to obtain a digital value for the fuel density.

Abstract: A closed loop fuel management system is disclosed in which an improved dual integral controller provides both transient and gross correction for an electronic fuel injection system operating at a predetermined air/fuel ratio. The controller has cascaded dual integrators including a primary integrator with a relatively fast integration rate utilized for transient control and a secondary integrator with a relatively slow integration rate utilized for gross control such as ageing effects and altitude compensation. The controller responds to several engine operating conditions and to rich fuel power demands to switch from closed loop to open loop control while maintaining the gross system correction provided by the operating point of the secondary integrator.

Abstract: A closed loop exhaust gas recirculation system for an internal combustion engine having an intake system, an exhaust manifold, a throttle disposed within the intake system for controlling air flow therein, a conduit coupling the exhaust manifold to the intake system for supplying exhaust gases back to the intake system for controlling the generation and emission of oxides of nitrogen and for improving driveability. The system includes a first memory pre-programmed with a look-up table of optimal values of absolute manifold pressure (MAP.sub.0) as a function of engine speed (RPM) and throttle position (.theta.). The actual operating parameters of absolute manifold pressure (MAP), engine speed (RPM) and throttle position (.theta.), or alternatively air flow (AF), are accurately sensed. The actual values of throttle position or air flow and RPM are used to address the first memory which outputs the pre-programmed optimal value of MAP.

Abstract: A dual mode control system for operating an electronic fuel injection system for an internal combustion engine so as to achieve an optimal compromise between engine emissions, fuel economy and driveability. A closed loop control circuit is provided which senses the amount of oxygen in the engine exhaust and normally drives an integrator in a closed loop mode of operation to operate the electronic fuel injection system at the stoichiometric air/fuel ratio at which the best conversion efficiency of hydrocarbons, carbon monoxide and nitrous oxides occur. An open loop control circuit senses high speed operation where hydrocarbons and carbon monoxide conversion are normally high and where nitrous oxide emission is not critical and clamps the output of the integrator to a predetermined value which operates the electronic fuel injection system at a nonstoichiometric, relatively lean, air/fuel ratio for improved fuel economy.

Abstract: A closed loop programmable EGR control system is disclosed. The EGR control system comprises a first read only memory having a look up table of base EGR pulse widths as a function of engine speed and absolute manifold pressure. This base EGR pulse width is corrected to a total desired pulse width by adding a correction pulse width obtained from a second read only memory. The second ROM stores values of the correction pulse width in a look up table as a function of engine speed and engine coolant temperature. This desired value of EGR pulse width is then compared to the actual EGR flow as sensed directly by a differential pressure transducer located in the exhaust gas recirculation conduit and an error signal is generated therefrom.

Abstract: A closed loop exhaust gas recirculation (EGR) control system for an internal combustion engine having an intake system, an exhaust system, a throttle disposed within the intake system for controlling air flow therein, a conduit coupling the exhaust system to the intake system for supplying exhaust gas back to the intake system for controlling the generation and emission of oxides of nitrogen and for improving drivability and avoiding engine roughness. The EGR control system of the present invention includes a first memory pre-programmed with a look-up table of optimal EGR values indicative of EGR valve position or the like determined as a function of engine speed and throttle position and a second memory pre-programmed with the look-up table of optimal EGR values determined as a function of engine speed and absolute manifold pressure.