Robert Boschgmbh

Hans Schnurle

Ulrich Drews

Peter Werner

Michael Horbelt

Richard Bertsch

Dieter Gunther

Bernd Kraus

Ulrich Steinbrenner

Erich Singer

Otto Glockler

Harro Herth

Lothar Winkelmann

Dieter Kirn

Wolf Wessel

Heinrich Knapp

Cornelius Peter

Herbert Arnold

Wadym Suchowerskyj

Thomas Wilfert

Klaus Streit

Rudi Mayer

Claus Ruppmann

Erwin Gloss

Helmut Moder

Jurgen Anlauf

Alfred Grassle

Gunter Rosenzopf

Werner Mohrle

Bernhard Schmidt

Rudolf Schwammle

Jurgen Penschuck

Peter Strauss

Urlich Drews

Wolfgang Rebmann

Siegfried Bottcher

A method of and a device for regulating air-fuel ratio of an internal combustion engine includes an oxygen or lambda probe and a signal processing unit connected to the lambda probe. The change-overs of the lambda signal at the output of the lambda probe are compared with a succession of adjustable first time intervals t.sub.1 and, when no change-over is detected during the first time interval, the output signal from the signal processing unit which controls the air-fuel ratio is abruptly changed in a jump. To avoid overshoot of the output control signal, there is provided a resetting unit by means of which the jump of the control signal is reversed when the change-over of the lambda signal occurs in an additional monitoring time interval t.sub.2 following the first monitoring time interval t.sub.1.

Method of and device for lambda-regulation of fuel mixture for an

A method and an apparatus for overrunning control in an internal combustion engine are proposed, which operate with an overrunning cutoff and the reestablishment rpm of which is dependent on rpm and on time. At the onset of overrunning, a higher reestablishment rpm is selected, and once the rpm falls below a predetermined rpm value the reestablishment rpm is reduced according to a time function to a lower threshold value. The method may be realized by a controlled system, as well as by a control apparatus operating with analog circuitry.

Method for operating an apparatus for a fuel control system of an

A fuel metering system having a .lambda. regulation device in which the delay periods known per se from the prior art are variable upon the switchover of the integration direction of an integrator included in the .lambda. regulation system. This variation produces a shortening of the delay period, as a result of which it is possible to prevent an excessive enrichment of the mixture. The invention relates to a controllable reduction of the individual delay signal as well as a control of the total duration of control exerted on the delay signals as they appear. The invention is independent of whether it is realized by either analog or digital circuit technology.

Fuel metering system for an internal combustion engine

A regulating device is described for regulating or adjusting the composition of the operating mixture of an internal combustion engine. When the engine or exhaust gas probe is still cold, the composition of the fuel-air mixture is controlled in an open-loop manner, and upon the attainment of a minimum operating temperature, the closed-loop regulating device for influencing the fuel-air mixture is activated. The activation of the regulating device is effected, when the engine is being operated under a load, after the attainment of a first, low temperature value; during engine idling, this is effected after the attainment of a second, higher temperature value. Via the throttle valve, a switchover is effected between two threshold values of a threshold switch.

Temperature responsive open/closed loop switching for lambda control

A method for operating a fuel-supply system using a lambda-control apparatus for an internal-combustion engine wherein the amount of fuel to be supplied to the internal combustion engine is a function of signals representing the speed (RPM), the engine load, the exhaust-composition, and the temperature of the exhaust-gas sensor together with the attainment of a given temperature of the engine as an additional control criteria for the lambda-control apparatus. The method further includes deriving a temperature signal from the internal combustion engine to operate a threshold element with a hystereses whose switching values lie at about 10.degree. C. and 50.degree. C. to 85.degree. C. for optimum fuel mixture in the combustion chamber. The output signal of the threshold element can be further utilized for a supplementary warm-up fuel enrichment for better ignition characteristics, engine smoothness, and exhaust gas composition. The apparatus according to the invention has transducers for sensing speed, load, exhaust gas composition and temperature together with a threshold element and a logic element for signals from a sensor in the internal combustion engine so that the lambda-control apparatus can be regulated as a function of the output signal from said logic element.

Method and apparatus for operating a fuel-supply system with lambda

There is described a method and an apparatus for use with the fuel preparation system of an internal combustion engine, for example, a fuel injection system which operates injection valves with electrical control pulses. When the gas pedal of a vehicle is actuated abruptly, the air flow measuring device of such systems is subject to oscillations around its equilibrium point, and the initial one of these swings is used to cause enrichment of the fuel-air mixture. The return swing generates an undesired lean signal which is suppressed by a 'damping circuit'. In addition, there is provided mixture enriching during steady applications of the gas pedal by means of a time-decaying enrichment signal generated by a slow acting circuit which operates in superposition to the action of the damping circuit. Both circuits may be suppressed by a blocking circuit during certain engine conditions, for example, during engine starting and engine overrunning as well as on the basis of temperature.

Method and apparatus for performing fuel mixture enrichment

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.

System for increasing the fuel feed in internal combustion engines

A method and an apparatus for generating fuel metering control pulse which may be used to control the operation of injection systems, carburetors, or any other controllable fuel metering mechanism. The system includes two signal generators one of which continually generates a signal related to engine conditions while the other is engaged in deriving therefrom a fuel metering control pulse of appropriate length. The duration of the pulses may be obtained by the charging and discharging constant of control capacitors or by a process of numerical countdown of digital data.

Method and apparatus for generating fuel injection control pulses for an

An apparatus for the open-loop or closed-loop control of the composition of the mixture desired in the combustion chamber of an internal combustion engine, which includes an exhaust gas sensor whose output signal together with other operational parameters, determines the mixture composition. The essential component of the apparatus is a storage unit with which charging and discharging sources controllable in accordance with the sensor signal are associated, wherein the magnitude of the charging and discharging signal is dependent on operational parameters. The storage unit may comprise a capacitor or a resistor-capacitor combination having one terminal connected to ground and another terminal efficiently connected with an operational voltage connection, so as to have in this manner an unequivocal association with a fixed potential.

Apparatus for controlling the mixture composition in an internal

A fuel injection control system generates control pulses which open the fuel injection valves of the engine. The pulse duration is proportional to the injected fuel quantity and can be altered in dependence on air temperature by a circuit which includes a temperature-sensitive resistor. The voltage at this resistor controls a transistor which supplies a supplementary charging current for a timing capacitor.

Apparatus for adapting engine fuel supply to ambient air temperature

Apparatus for correcting the fuel apportionment signal in an internal combustion engine during an alteration in quantity of the fuel which includes a first storage device charged according to the rpm, the storage value of which determines the content of a second storage device in accordance with certain time intervals and according to a specific function and the alteration signal of the second storage device is used for the correction of the fuel apportionment signal.

Apparatus for correcting a fuel apportionment signal in an internal

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.

Method and apparatus for controlling fuel management for an internal

A device for metering fuel in an internal combustion engine which comprises sensors for operating parameters, an acceleration detecting stage with a subsequently connected pulse generating stage as well as a pulse lengthening stage, and a fuel metering system wherein the acceleration detecting stage is indirectly and/or directly associated with at least one of a plurality of components including an oscillation stopper (to prevent renewed triggering in case of an oscillation-carrying input signal), a blocking stage (for unequivocal and secure triggering), a repetition stopper (to avoid multiple triggering during gradual and longer-term signal rises), and a switching suppressor (to prevent a voltage rise after a switching step from being evaluated as an instance of acceleration) so that the device serves to operate the acceleration enrichment of the fuel-air mixture for the internal combustion engine with a minimum of disturbance thereby attaining optimum acceleration processes.

Fuel metering device for an internal combustion engine

The cyclic control pulses for actuating the fuel injection valves of an internal combustion engine are extended during engine starting at low temperatures. The degree of pulse extension, i.e. of fuel enrichment, is made dependent on engine temperature and decreases as a function of cranking time. In addition, a repeated starting attempt will be accompanied by reduced pulse extension to prevent excessive enrichment of the mixture. The pulse extension may also be retained for a period of time after engine cranking to insure smooth running.

Method and apparatus for fuel control of an internal combustion engine

This invention relates to an apparatus for controlling at least one electrical switching element in internal combustion engines, particularly the main relay of the voltage supply, in accordance with one operating characteristic and with a switch position which indicates an operating condition, in which the signal corresponding to the operating characteristic can be fed to a storage device whose charging and/or discharging process can be influenced by the switch relative to the ignition with the value of the storage signal serving to control the electrical switching element. Furthermore, the signal in accordance with the operating condition and, indirectly or directly, corresponding to the operating characteristic can be fed to a connection point whose output signal can be switched to a switching device for heating the heating wire in an air flow rate meter to a red-hot condition.

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Walheim, Germany

Hans Schnurle