Fuel injection system
Electronic fuel injection system for internal combustion engines
Fuel-air metering and induction system
Exhaust gas recirculation system of a motor vehicle
Exhaust pressure regulating system
Method and apparatus for controlling the operating mixture supplied to an internal combustion engine
Fuel demand engine control system
Dual purpose pressure sensor
ApplicationNo. 06/035036 filed on 05/01/1979
US Classes:123/478, Actuator circuit (e.g., engine condition responsive electronic circuit actuates injector valve)123/445, Fuel injection system123/676Exhaust gas temperature or pressure repsonsive
ExaminersPrimary: Myhre, Charles J.
Assistant: Nelli, R. A.
Attorney, Agent or Firm
International ClassesF02D 41/32 (20060101)
F02B 75/02 (20060101)
AbstractAn air fuel ratio management system having a calibration correction for the pressure differentials between the exhaust and intake manifolds of the engine is disclosed. The differential calibration corrects the air/fuel ratio of the system for the variable internal exhaust gas recirculation occasioned by changing restrictions to flow found in the intake and exhaust manifolds. In one implementation a differential pressure sensor communicates with both the intake and exhaust manifolds to develop a differential pressure signal. The differential pressure signal is thereafter applied to a function circuit which generates a pressure correction signal. An electronic control unit receives the pressure correction signal and utilizes it to modify the air/fuel ratio calibration according to the functional conversion. In the preferred embodiment the function circuit comprises a voltage controlled linear current source. In another implementation individual pressure sensors are used for each manifold to generate signals to a difference circuit which subtracts the intake manifold absolute pressure from the exhaust manifold absolute pressure to form the differential pressure signal. In either implementation incremental or proportional modification of a variable duration fuel pulse from the electronic control unit can be obtained by the pressure correction signal.