Abstract: The air flow rate meter in the induction tube of an internal combustion engine is a pivoting sector which has axial valve elements which cooperate with similar elements in the pivotal shaft to provide fuel metering in proportion to the excursion of the air flow rate meter due to the air flow. Parasitic leakage flow of air past the side walls of the pivoting sector is reduced by providing surface features, such as raised strips or fences, bored depressions, indentations and the like which cooperate with the induction tube wall which may have similar features to induce flow impedance and prevent unwanted air flow past the meter.

Abstract: What follows is a description of a fuel injection system for an internal combustion engine which employs exhaust gas recycling. The engine has a suction tube leading to the engine and an exhaust pipe leading from the engine, while the system includes a recycle line connecting both the exhaust pipe and the suction tube, and a control mechanism. The control mechanism can be located either in the suction tube, the exhaust line or the recycle line and controls the pressure therein in order to control the recycled exhaust gas flow rate. The system further has a regulating structure which regulates the quantity of the injected fuel in conjunction with the control mechanism.

Abstract: A fuel injection system for a mixture compressing, externally ignited, internal combustion engines employing continuous injection into a suction tube includes a control pressure circuit provided with a throttle. The metering valve is controllably associated with the throttle so that the pressure difference at the metering valve can be changed by changing the pressure difference at the throttle.

Abstract: A fuel injection system includes a metering valve assembly whose control slide is actuated by the air flow through the induction tube and by an opposite restoring force provided by fluid pressure. The magnitude of this restoring force may be altered by the action of a pressure control valve. The back pressure downstream of this control valve and downstream of a main fuel system control valve is regulated by a back pressure regulating valve. This valve is responsive to signals related to the atmospheric pressure or to operating parameters of the engine, e.g., the induction manifold pressure and it regulates the back pressure of the fuel to maintain a desired fuel-air ratio.

Abstract: A fuel injection system for externally ignited internal combustion engines in which a fuel metering and distributing valve is controlled by an air sensing element disposed in the air suction tube of the engine and by structure which is adapted to alter the restoring force exerted on the air sensing element through the fuel metering and distributing valve. The noted structure includes a control pressure conduit, an uncoupling throttle disposed between a fuel supply conduit and the control pressure conduit, at least one electromagnetic valve disposed in the control pressure conduit for varying pressure in the control pressure conduit in dependence on at least one operating parameters of the engine, at least one pressure regulating valve also serving to vary the pressure in the control pressure conduit, and a storage element for hydraulic integration during pressure changes in the control pressure conduit.

Abstract: In a fuel injection system for an internal combustion engine, a fuel metering valve is controlled by an air sensing element disposed in the air intake tube for metering fuel quantities proportionate to the intake air quantities, and by an electromagnetic valve and an associated control structure which varies the air-fuel ratio by changing the pressure difference across the fuel metering valve, as a function of engine temperature during warmup, then as a function of, for example, the oxygen content in the engine exhaust gases.

Abstract: A fuel injection system for an internal combustion engine is controlled by a follower control loop. The fuel quantity is arbitrarily set by the gas pedal and a first potentiometric transducer generates an electrical command signal. The air flow through the induction tube constitutes the controlled variable whose magnitude is transformed into an electrical signal by a second potentiometer coupled to an air flow rate meter. The two signals are compared at the input of a control amplifier which drives a servomotor. The servomotor adjusts the opening of the air throttle valve of the engine, thereby changing the air flow through the induction tube until the air flow rate meter signals that the air quantity is proportional to the metered out fuel quantity.

Abstract: A fuel supply and metering valve assembly used for injection of fuel to an internal combustion engine includes a control pressure circuit which determines the restoring force on the movable member of the fuel metering valve. The magnitude of the control pressure, and hence the fuel quantity metered out by the valve assembly can be altered by the intermittent actuation of a pressure relief valve which controls a fluid bypass. The duty cycle of the intermittently acting bypass valve is controlled by a regulating device which responds to the indications of measuring transducers, for example an oxygen probe located in the exhaust line of the engine. The transducer signal is superimposed on a sawtooth voltage at the input of a differential amplifier which interacts with other control circuitry so as to vary the length of time during which the electromagnetic bypass valve is energized.

Abstract: A fuel injection system for an internal combustion engine whose air induction tube contains an air flow rate measuring member with non-linear operating characteristics, coupled to a potentiometric transducer which produces the electric command variable for a follower control loop. A control amplifier drives a servomotor which sets the metering slide of a fuel metering valve assembly. The servomotor shaft is coupled to a second potentiometric transducer whose output is compared with the command variable in a bridge circuit connected to the input of the control amplifier. The mechanical link between the servomotor and the fuel metering slide has a non-linearity similar to that of the air flow rate measuring member.

Abstract: Control systems in which transition between oxidizing and reducing state of the exhaust gases is sensed, and the input to the engine modified in accordance with sensed exhaust gas composition utilize a sensor which has an output signal having a transition jump, the extent of the jump being highly temperature dependent; in accordance with the invention, a signal is derived representative of change in level of the transition jump, as a function of temperature, and the control circuit responsive to the transition jump, and controlling input to the engine is modified in accordance with the signal repesentative of level change of the transition jump, to compensate for temperature-dependent changes.

Abstract: A fuel injection system for externally ignited internal combustion engines preferably has one fuel injection location in the air induction tube (manifold). The metering of fuel occurs independently of the condition of the air prevailing at the injection location, the injection location is disposed ahead of the junction of the air induction tube which leads to the individual engine cylinders. Air is brought to a high velocity by means within the induction tube and impinges, at this high velocity, immediately on the injected fuel, enveloping the same. As a result, the mixture preparation is effected without wetting of the inner wall of the induction tube and the means which bring the air to the required high velocity.

Abstract: For detoxicating the exhaust gases of an internal combustion engine an in-series arrangement of a first reactor and an oxidizing reactor is provided with the exhaust line of the engine along with an oxygen measuring element and structure for producing two additional air streams fed to the exhaust line. The first reactor reduces the nitrogen oxides in the exhaust gas and the second or oxidizing reactor oxidizes the hydrocarbons and the carbon monoxide in the exhaust gas. The oxygen measuring element is mounted to the exhaust line and regulates the mass ratio of air to fuel on the suction side of the engine. The first additional air stream is injected into the exhaust pipe in the flow direction upstream of the oxygen measuring element. The quantity of this air stream is regulated and corresponds to the fuel throughput of the engine so that when the oxygen measuring element measures a stoichiometric mixture (.lambda.=1) a slightly rich air-fuel mixture (.lambda. .apprxeq.0.98-0.99) is supplied to the engine.

Abstract: The airflow rate through the induction tube of an internal combustion engine is measured by a first transducer which delivers a set point signal to a control amplifier. The amplifier also receives a feedback signal from a second transducer which monitors the position of a servo-motor controlling the quantity of fuel metered out to the engine. The feedback loop maintains a desired fuel-air ratio and includes provision for calibration and adjustment.

Abstract: The output of an oxygen sensor is fed in parallel to the inputs of amplifiers having amplification in different portions of the sensor output range and having different gain. The amplifier outputs are combined in a summing circuit. The result is to smooth out the characteristic of the measurement and to produce a signal that can drive an indicator to provide a meaningful indication in terms of air number. The temperature of the oxygen sensor must be regulated or compensated for for good results.