Abstract: 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.

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: 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.

Abstract: 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.

Abstract: 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.

Abstract: A fuel injection control circuit includes a monostable multivibrator for generating injection valve control pulses. The circuit includes a trigger sub-circuit which controls the switching characteristics of the monostable multivibrator in a well-defined manner which is immune to electrical noise and to voltage fluctuation in the supply lines of the vehicle.

Abstract: 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.

Abstract: An electronic circuit is described for use with an existing fuel injection system in which fuel control pulses are generated on the basis of air flow rate, engine speed and exhaust gas composition. In particular, the existing fuel injection system is assumed to include an exhaust gas sensor with a signal integrator and a throttle position switch which indicates a closed throttle. It is also assumed that the fuel injection system shuts off fuel control pulses when the throttle is closed and engine speed drops below a predetermined value. The present circuit is intended to recognize this fuel shutoff and to set the integrator at an average value irrespective of the "too lean" signal which it receives from the exhaust gas sensor. In this way, upon termination of fuel shutoff, the engine will receive an average mixture rather than a highly enriched one.

Abstract: A control circuit for a fuel injection system which modifies the control pulses of the electromagnetic valves during engine starting. The width of the normal injection control pulses determines the amount of fuel and is derived from engine parameters, in particular rpm and air flow rate. When stating the engine, the control circuit is actuated by the starting switch of the engine and causes suppression of the normal control pulses. A multivibrator generates substitute starting control pulses whose duration is changed by altering the time constant of the multivibrator in response to the signal from a temperature transducer.

Abstract: A frequency divider circuit and variants thereof, intended for use with the fuel injection system of an internal combustion engine. The primary trigger signal is one derived from a rotating engine member and this signal is used to generate two input pulse trains of opposite relative phase. A basic dividing block includes two bistable multivibrators formed by gates with crossed feedback. The inputs to these multivibrators are provided by two-input gates and the input pulse trains are applied, respectively, to the input gates ahead of the first and second multivibrators. The second inputs of the input gates receive the direct or crossed-over outputs of the multivibrators. Additional circuitry is disclosed for providing odd dividing ratios, e.g. 1:3.

Abstract: 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.

Abstract: A control circuit for a fuel injection system of an internal combustion engine supplies a corrective current to the main multivibrator during and/or after engine starting. The corrective current is supplied on the basis of temperature dependent signals and on the basis of the pulse width of the primary injection signals, which is related to engine rpm and load.

Abstract: To provide an undistorted square wave output signal under control of a switch subject to contact chatter so that the square wave will accurately reflect the operating instant of the switch, as commanded, regardless of contact chatter, a timing circuit is provided having a timing capacitor and a charge and discharge circuit therefor, connected to a threshold circuit, the threshold circuit response level and the charge circuit of the timing capacitor being dimensioned to cause the capacitor to charge to a level such that the threshold circuit responds only when the switch has changed state, typically closed after interrupting an inductive load, such as the primary of a spark plug, for a predetermined time period as determined by the switch contact chatter characteristics of the switch itself, for example about 0.

Abstract: A control pulse generator for the fuel injection system of internal combustion engines. The rpm-dependent trigger signal is applied simultaneously to two multivibrators one of which generates pulses whose length is determined by engine parameters while the other generates pulses of fixed length. A logical circuit selects the longer of these pulses so that the fuel control pulse will always have at least a minimum length.

Abstract: 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.

Abstract: To permit connection of the input trigger stage to a wide variety of signal sources, such as different types of ignition systems (transistorized ignitions, coil-type ignitions, mechanical breaker system ignitions, and the like), a voltage divider is connected across the supply circuit, and the input signal is applied to a dual collector transistor forming the trigger or threshold stage, one collector of the transistor being connected to the output of the trigger stage and the other being connected to a protective circuit controlling bypassing of input signals of excessive voltage, or energy of either polarity and thus protecting the dual collector transistor.

Abstract: To prevent bucking of a fuel injection operated automotive engine, under transient dynamic conditions, due to resilient suspension thereof, a timing capacitor in the fuel injection system has an auxiliary capacitor connected in parallel thereto over a diode, the auxiliary capacitor having its own charge circuit, and the diode and charge circuit being so arranged that the diode becomes conductive when the voltage across the main capacitor exceeds the voltage across the auxiliary capacitor, thus delaying and flattening the charge rate to the main capacitor without, however, detracting from total charge being placed on both capacitors to prevent excessive changes in fuel valve injection timing under transient engine operating conditions.