摘要:
The maximum speed of an internal combustion engine is limited by a device which compares the period of rpm-synchronous pulses with the time constant of a reference multivibrator. If the engine rpm is so high that a pulse terminates prior to expiration of the reference time period, a gate is activated and acts through further multivibrator circuits to interrupt the fuel delivery to the engine, e.g., the fuel injection control pulses are suppressed. If the maximum rpm is exceeded only intermittently, the device restores normal fuel injection control pulses after a predetermined number of pulses has been suppressed. If the maximum rpm is exceeded continuously, the device restores normal fuel control somewhat later than the time at which the engine speed drops to below maximum rpm.
摘要:
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.
摘要:
An apparatus for use in association with a fuel mixture preparation system for an internal combustion engine in which the output signal from an oxygen sensor located in the exhaust system is used to provide closed-loop control of the mixture ratio supplied by the mixture preparation system. The apparatus includes a principal comparator in which the sensor signal is compared with a reference value and a subsequent integrator which supplies correcting signals to the mixture controller. A special circuit between the principal comparator and the integrator can delay the signal transmission between these two elements in one direction of change, thereby causing an effective shift of the point of operation of the control loop to a different point in the sensor output curve, to compensate for aging, etc. The feedback branch of the integrator includes circuitry which effectively provides two different constants of integration to enhance smooth running at low engine speeds and to improve the control response at high engine speeds. The invention may be used with any kind of mixture preparation system, e.g., carburetors, intermittent injection systems and continuously acting injection systems.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
A fuel mixture control apparatus for an electronic fuel injection system for internal combustion engines. In a warm-up controller, the fuel injection control pulses are lengthened for enrichment of the fuel-air mixture during engine warm-up on the basis of signals supplied by a temperature transducer. In order to make the warm-up enrichment dependent on prevailing engine states, for example on the conditions of idling and partial or full load, circuitry is provided to sense these conditions and to suitably alter the enrichment factor. A further circuit suppresses the dependence or enrichment on engine status during engine starting. Various embodiments are presented.
摘要:
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.
摘要:
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.