Abstract: A fuel injection system for internal combustion engines is proposed which serves the purpose of fuel injection into the air intake tube of the engine. The fuel injection system includes a fuel injection valve, which is supported upstream of a throttle valve in a holder body disposed coaxially in the air intake tube. A fuel supply line leads to the fuel injection valve, extending in a downwardly directed manner toward the fuel injection valve and away from a deaeration chamber. A fuel return line leads away from the fuel injection valve, extending in an upwardly inclined direction to discharge into the regulating chamber, disposed at a higher level, of a pressure regulating valve. A fuel feed line originating at a fuel supply pump terminates in an upwardly directed manner into the dearation chamber, which communicates via a dearation nozzle with the regulating chamber, so that vapor bubbles can escape upstream of the injection valve into the return side of the injection valve.

Abstract: An electromagnetically actuatable valve, especially an injection valve for fuel injection systems which supply internal combustion engines with fuel, is proposed in which the fuel injection valve encompasses a valve chamber and a core upon which a magnetic coil is mounted by means of a carrier body. Fuel supply openings discharge into a flow passage provided around the magnetic coil. Vapor bubbles dissolved in the fuel may be flushed out of the flow passage via a first restriction into fuel return openings which communicate with a fuel return line. On the other hand, the fuel may flow from the flow passage into the collecting chamber which houses a valve component and a valve seat. Vapor bubbles which may appear near the valve component may be flushed out via a second restriction which is provided in the interior of a core to reach the fuel return openings. Thus, disturbances with fuel injection, especially during the "hot start" of the internal combustion engine, are avoided.

Abstract: A system for increasing the fuel feed in internal combustion engines during acceleration in order to ensure better performance comprising an acceleration detector, an enrichment stage, a proportionating member associated with a differentiating member, all connected to be responsive to at least one sensing member whose output signal is variable according to the engine operating conditions. The operating parameters sensed may be, for example, speed, air flow rate in the intake manifold, starting conditions, as well as the temperature of the internal combustion engine.

Abstract: A control circuit of a fuel management control system for internal combustion engines monitors the operation of an exhaust line sensor. When the oxygen sensor is perceived to be inoperative, for example, due to low ambient temperature, the previously closed loop control process governing the fuel management control signals is interrupted and a direct forward control process is substituted therefor. The reference voltage is changed during this time for eventual adaptation to the changeover to closed loop feedback control after the oxygen sensor again becomes operational.

Abstract: The fuel mixture preparation system of an internal combustion engine, especially a continuous fuel injection system, is engaged during intended engine accelerations by a pressure sensor in the induction manifold which responds to increasing manifold pressure to close a switch. The switch closure affects a pressure control valve that changes the control pressure in the fuel injection system and thereby causes temporary fuel enrichment until the differential pressure in the pressure sensor has returned to equilibrium. The signal from the pressure sensor may be extended arbitrarily by interposition of an electronic timing circuit which is constructed as an integrating circuit so that its output signal, when processed by a comparator, will produce a proportionally extended actuation signal for the control valve.

Abstract: A method and apparatus for adjusting the reference or set-point value which is used in a closed-loop fuel control system for comparison with the actual value signal from an exhaust gas analyzer or sensor. The frequency of amplitude alternations of the sensor signal is a measure of engine speed and gas throughput rate. Accordingly, the invention provides generation of a quasi-D.C. signal whose amplitude is related to the frequency of sensor signal alternations. This signal is then used to change the supply voltage for a voltage-dividing circuit that supplies the reference voltage to the comparator circuit. The invention describes continuous and discrete adjustments of the reference signal.

Abstract: A fuel injection system for an internal combustion engine includes electromagnetic injection valves controlled by a fuel control unit which receives signals from a camshaft actuated switch, a position-dependent throttle transducer and an oxygen sensor. When the oxygen sensor changes output levels, the transmission of this information is delayed, by the action of a switching transistor controlled by a monostable multivibrator, for a period of time equal to the internal time constant of the multivibrator.

Abstract: A fuel injection system for an internal combustion engine includes electromagnetic injection valves controlled by a fuel control unit which receives signals from a camshaft actuated switch, a position-dependent throttle transducer and an oxygen sensor. When the oxygen sensor changes output levels, the transmission of this information is delayed, by the action of a switching transistor controlled by a monostable multivibrator, for a period of time equal to the internal time constant of the multivibrator.