Abstract: An electronic fuel injection system is provided with a closed loop control having a plurality of loops for proportioning a mixture of air and fuel delivered to an internal combustion engine. The system has a sensor for providing an electrical signal, the magnitude of which varies in proportion to the concentration of a constituent of exhaust gas from the engine. A first of the loops compensates for small amplitude, short term disturbances of said signal. The second loop compensates for large amplitude, long term signal disturbances. Signals from the first and second loops are combined to produce a composite signal that maintains precise control over the average air/fuel ratio while generating rapid small amplitude fluctuations in that air/fuel ratio which shortens the response time of the system and increases its ability to reduce exhaust gas pollutants.

Abstract: A fuel injection system employs injectors having energizing coils and means for generating an actuating pulse to the injector. The system includes a correction means for applying a correction to the injector actuaing pulse to correct for the effect of at least one incidental system variable on the effective response of the injector to the actuating pulse. The incidental system variables are: the impedance of the energizng coil, the specific resistance of the wire used in the coil and the voltage supply in the fuel injection system. The correction means may be a constant current source drivng an output transistor biased to operate in a proportional conduction region.

Abstract: A fuel injection system for a spark ignited, internal combustion engine employs sensors which measure engine operating parameters to control the duration of actuating pulses applied to at least one fuel injector. One of the sensors measures engine temperature and the pulse duration is increased at lower engine temperatures to compensate for the lower volatility of the fuel at such lower temperatures. The output of a manifold vacuum sensor is differentiated to derive a signal proportional to the rate of increase of engine load and that is used in combination with the engine temperature sensor to increase the duration of an injector actuating pulse in amounts proportional to the rate of increase of engine load. The amount of increase in duration of the pulse varies inversely with engine temperature.

Abstract: A fuel injection system for an internal combustion engine employs a relatively low pressure pump to provide fuel to injectors located at the engine cylinders. A booster device for maintaining the fluid pressure constant, at a substantially higher level, is connected in series with the line between the pump and the injector and includes one way valves at its inlet and outlet. The booster employs a chamber connected to the fuel line and pressurized by a piston which acts to contract the chamber volume under the force of the coil spring. The piston is cocked against the spring at regular intervals to renew the original volume of the chamber by an arm driven from the engine crankshaft. Sealed volume converters having flexible diaphragm walls are disposed adjacent to the inlet and outlet of the booster device and in the fluid conduit adjacent the injectors to obviate sharp drops in the fluid pressure in the fuel line when the injectors actuate.

Abstract: A multi-channel, sequentially timed fuel injection system for an internal combustion spark ignited engine employs a solenoid actuated injector valve for each cylinder controlled by the outputs of separate variable width pulse generators. The pulse generators each employ a resistance-capacitance discharge timing circuit and a single thermistor, common to all the generators, sensitive to engine temperature is connected to the RC circuits of the generators in a first circuit configuration during starting of the engine which provides a wide range of fuel delivery rates for starting and in a second circuit configuration during normal operation in which the various RC circuits are isolated from one another so that interaction of the variable width pulse generators does not occur as a result of the common thermistor connection during normal engine operation.

Abstract: A control system for a positive displacement, electrically actuated fuel pump receives one trigger pulse per engine cycle during normal operating conditions and a plurality of pulses per cycle during starting conditions from a computer circuit forming part of a fuel injection system. A control circuit generates one driving pulse for the fuel pump for each trigger pulse as long as the period between the pulses remains sufficient for the pump to complete its cycle and deletes control pulses to the pump when the engine speed is excessively high. A variable displacement electric pump is controlled to provide the engine with a fuel flow proportional to its operating rate by a variable on-time switching system controlled by an engine speed sensor and/or load sensor.

Abstract: A fuel injection system employs an electromagnetically actuated injector connected to a source of fuel and a variable width, constant current electrical pulse source controlled by engine operating parameter sensors, to energize an injector coil in timed relation to the engine operation and thereby vary the fuel volume provided to the engine as a function of the parameters. A circuit including the injector coil modifies the time constant of an R-C circuit in the pulse source to modify the pulse width as a function of the voltage across the injector coil, which varies as a function of fuel temperature in the injector to maintain the fuel mole weight provided to the engine independent of variations in the fuel temperature adjacent to the injector.

Abstract: A fuel injection system for a multi-cylinder engine includes means for generating a sequence of pulses during each cycle of the engine. These pulses trigger variable width pulse generators, sensitive to the engine operating parameters. The variable width pulses are provided to the injectors so that each ejector fires once during an engine cycle and their firing times are spaced over the cycle. During start-up, the pulse widths are diminished and all of the injectors are fired each time the sequencing circuitry provides an output pulse. The total charge provided to each cylinder is thus distributed over the engine cycle, insuring the presence of the proper quantity of fuel for optimum flammability to achieve start-up of the engine in at least one of the cylinders.

Abstract: A fuel injection system for multi cylinder engine employs a plurality of separate computing circuits for generating variable width control pulses to fuel injectors. Each channel actuates at least one fuel injector during more than 50% of an engine cycle. To derive the start times for these four pulses, a counter is advanced in timed relation to the operation of the engine by pulses from the ignition primary circuit. To control the phase of the firing pulses relative to the cycle time of the engine the counter is reset once each engine cycle by a pulse derived from one of the spark plug leads.

Abstract: An electromagnetically operated valve which may be used as a fuel injector in a fuel injection system for an internal combustion engine. The valve includes: a discharge means, a sealing means, a fluid conduit, an electrical conductor, an electromagnetic circuit, a travel limiter and a biasing means. The sealing means intermittently opens and closes the discharge means. The electromagnetic circuit includes: a movable armature, a center pole, a combined housing and outer pole, a coil for magnetizing said electromagnetic circuit in response to said electrical signal and a flux path. The armature is a low mass, dual purpose disc which cooperates with the sealing means. The armature is disposed within and in slideable contact with the housing. The travel limiter limits travel of the armature in an upstream direction and defines a single air gap in the flux path between an upstream face of the armature and a downstream end of the first pole when the armature is in an upstream open position.