Abstract: A spark-ignition engine has adaptive adjustment of the size of its fuel rations in dependence on misfires in the engine. A misfire is identified as an abnormal deficiency in energy conversion, this being detected by means of a mechanical energy discriminator which compares the quanta of energy derived from different combustion cycles.The preferred embodiment is a single cylinder engine having a fuel injector valve. The valve is normally closed, being opened for a short interval during each combustion cycle. The size of a fuel ration is regulated by varying the duration of opening of the valve. The duration of opening of the valve is automatically adjusted in dependence on the frequency of misfires in the cylinder. A misfire is detected by means of a decelerometer which compares engine speeds during successive combustion cycles. When a misfire is detected, the fuel rations are automatically increased.

Abstract: A control apparatus for an internal combustion engine includes a plurality of sensors for producing signals indicative of operating conditions of the engine, an input/output unit adapted to receive sensed signals and to deliver control signals to actuators which control an energy conversion function of the engine and a central-processor unit coupled with the input/output unit and adapted to execute an arithmetic operation for producing data to be sent to the input/output unit. The input/output unit includes a first register file having a plurality of registers for storing constants and data produced by the central processor unit and a second register file having a plurality of registers for storing signals indicative of conditions of the engine as of a selected instant in time during which the engine is operative.

Abstract: The calculation of an adjustment value, which is determined by the concentration of oxygen in the exhaust gas, the opening of a throttle valve provided in an intake air passage to the engine, the engine temperature, etc., is started every time a predetermined number of repeatedly produced start signals, the repetition rate of which corresponds to the rotational speed of the crankshaft, occur. A basic value for fuel supply, T.sub.p =k Q/N, is calculated from the engine operating parameters; the amount of flow of intake air into the engine, Q the rotational speed of the crankshaft, N, and a constant k, and adjusted according to the adjustment value to obtain a control output signal, in the vicinity of the next start signal after said predetermined number.

Abstract: Small change in the period of a crank-angle signal which is generated at every crankshaft rotation of a predetermined angle is not faithfully reflected to a false crank-angle signal which is used by a fuel injection control device for detecting the engine's running speed. Thus, even when the actual running speed is varied, the running speed recognized by the fuel injection control device doesn't change faithfully to this variation. Therefore, the amount of fuel injected into the engine, which amount is calculated in accordance with the running speed, doesn't vibrate with the variation of the running speed, preventing the surge phenomenon from occurring.

Abstract: A fuel injection valve of an internal combustion engine is opened at a predetermined crank angle position. A counter starts to count pulses from a clock pulse signal generator at the predetermined crank angle position, and produces a signal to close the fuel injection valve when the accumulated count in the counter reaches an integer value which corresponds to the ratio of Ti to Tc where Ti is the fuel injection time duration, calculated by a calculating means from engine operational parameters, and Tc is the period of the signal from the clock pulse signal generator. The clock pulse signal generator is controlled by the calculating means, and the period Tc of its output signal is thereby varied. The ratio of Ti to Tc should preferably be selected so as to be as close to the capacity of the counter as possible.

Abstract: An integrated closed loop engine control is disclosed in which the fuel delivery and timing functions of the engine are closed about a measurement of the engine's instantaneous rotational velocity. Signals indicative of the profile of each torque impulse imparted to rotary output member of the engine from the burning of an air/fuel mix in the engine's combustion chambers are generated and electrically analyzed to detect perturbation caused by deviations of at least two different engine operational parameters from desired values. Feedback correction signals indicative of the magnitude of the detected perturbations are generated to correct the fuel delivery and timing functions of an engine control to minimize the difference between the actual operating parameters and the desired values.

Abstract: A closed loop engine roughness fuel control for an internal combustion engine operative to maintain the operation of the engine at a predetermined roughness level is disclosed herein. The control measures two rotational intervals within each torque impulse imparted to the engine's crankshaft by the combustion process and generates a speed normalized engine roughness signal indicative of the engine's actual roughness. The engine roughness signal is multiplied by the engine speed and summed with a reference signal to generate a bias signal operative to modify the quantity of fuel being delivered to the engine maintaining the operation of the engine at a predetermined roughness level. A signal indicative of the first derivative of the engine speed is also summed with the reference and roughness signal to compensate for false roughness signals generated during transient modes of operation.

Abstract: In an electronic engine control apparatus in which ignition timing and fuel injection quantity are calculated from the negative pressure in an intake manifold of the engine or from a flow rate of suction air and the rotational speed of the engine, a reference register group is constituted of register for storing the result of the calculation while an instantaneous register group is made up of registers for storing the instantaneous states of actuators. One of the registers of the instantaneous register group is selected according to a stage timing signal, so that the contents of the two registers selected are compared with each other for producing control pulses for driving actuators such as an ignition coil or fuel injector.

Abstract: A fuel consumption measuring apparatus for an internal combustion engine equipped with an electromagnetic fuel injection valve, comprising a fuel injection control means which calculates a proper value of fuel to be injected into the engine, and which then corrects this value in accordance with the characteristics of the electromagnetic fuel injection valve and controls the valve thereby, and a totalling means, which, in synchronization with the signals for controlling the valve, totals the values of the amount of fuel to be injected. In an embodiment, the totalling means is capable of subtracting a first predetermined value from the total held therein, and the apparatus further comprises a decision means which at regular time intervals judges whether the totalled value in the totalling means is greater than a second predetermined value or not; and, if it is, outputs an output pulse signal and also controls the totalling means to cause it to perform the subtraction.

Abstract: An electronic test instrument for facilitating the analysis of a machine's response to cyclic perturbations in one of its control parameters and for adjusting the control parameter based upon the observed response so as to optimize the machine's performance. The instrument permits manual control over the rate and magnitude of the perturbation, the amount of bias, i.e., the deviation of the actual operating point from the optimum, and the upper and lower limits between which correction is permissible. To prevent undue hunting of the control parameter about an operating point, the instrument includes a buffering network that requires that the system call for a predetermined number of control parameter adjustments in a given direction before an actual correction will be effected. The number is selectable by manually settable switches.

Abstract: An internal combustion engine fuel mixture control system is provided for use with an engine having a fuel supply and an intake air supply connected to the engine wherein the fuel and air mix to provide a combustible fuel/air mixture for the combustion engine. A fuel flow sensor is connected to the fuel supply line for the engine while an air flow sensor is similarly connected to the air intake of the engine and the outputs from the sensors are fed to a proportionator which provides an output signal representative of the instant fuel/air ratio for the engine and this output is coupled to one input of a differential amplifier. The other input of the differential amplifier is connected to a fuel/air ratio reference so that the output from the differential amplifier is representative of the difference between the reference and the actual fuel/air ratio for the engine. The output fromm the differential amplifier is used to vary the fuel flow to the engine.

Abstract: An electronic engine control apparatus in which the timing of the ignition and the fuel injection are calculated from a negative pressure in the intake manifold of the engine or the flow rate of suction air and the rotational speed of the engine. A reference register group is constituted of registers for storing the result of the calculation while an instantaneous register group is made up of registers for storing the instantaneous states of actuators. One of the registers of the reference register group and one of the registers of the instantaneous register group are selected according to a stage timing signal so that the contents of the two registers selected are compared with each other.

Abstract: An electronic control apparatus for an internal combustion engine having engine sensors, actuators, and a signal processor, contains an improved interface unit for coupling signals to the actuators in response to an output from the processor based upon sensor signals. The interface unit includes a scheme for generating event timing signals in accordance with the prescribed timing signal pattern generated by a stage pulse generator. Depending upon the operational conditions of the engine, the processor supplies a control code through which the timing signals that are produced are altered. This control code is used to alter the rate of occurrence or frequency of generation of the timing signals so that specific actuator control functions may be varied depending upon the engine operation conditions.

Abstract: A device is proposed for determining a fuel metering signal for an internal combustion engine comprising a tachometer, a load detector, as well as a storage element and a summing member. The load signal is preferably selected at certain times and then stored temporarily, wherafter the load signal is optionally corrected, multiplied with a time interval, and the sum total of the multiplication results represent a value with respect to the metering signal. Preferably, the signals are processed in a digital fashion, and the load signal is corrected after having been digitized. This is done because for example, in case of a hot-wire air flowmeter, there is no linearity between air flow (air mass flow) and the output signal of the air flowmeter.

Abstract: There is described a method and apparatus for use in association with the fuel injection pumps of Diesel engines to time the moment of injection. The method and apparatus described relate to a closed-loop control system which engages a final control element in the fuel injection pump that changes the injection timing, i.e. the onset of fuel delivery and, hence, the onset of fuel injection. The controlled variable is the moment of fuel injection, detected by suitable means placed near the injection valves. A set-point value for this instant is derived on the basis of stored data which correlate the correct moment of injection as a function of engine speed with various optimum conditions, for example, low fuel consumption, low smoke generation, low noise, etc. The selection of the proper characteristic curve from the stored data set is made automatically or manually.

Abstract: An electronic fuel feed system wherein pulses generated in synchronism with the revolutions of an engine are multiplied by N, the suction air of the engine is measured by a swirl-type air flow meter, the pulses increased N times as fall within a pulse of the air flow meter are counted, and the quantity of fuel supply is calculated from the inverse number of the count value.

Abstract: A digital advance control system of the type including a digital computer which receives input data of various engine operating parameters including the number of pulses corresponding to the ignition angle from a tachometer device in which the data from the tachometer device is to be interpolated. The data to be interpolated is applied to an attenuator circuit which includes a subtracter which receives the higher order bits of the data and a reversible counter whose higher order bits are also applied to the subtracter. The output of the subtracter is applied to a preselection counter or a binary rate multiplier which controls the application of clock pulses to the reversible counter.

Abstract: First electrical pulses are generated in response to the quantity of air inducted per unit time and second electrical pulses are generated in response to the speed of revolution of an engine crankshaft. A counter is provided which counts the number of second electrical pulses for an interval between successive ones of the first electrical pulses. The counted number of second electrical pulses is fed into a computer where the signal is processed to derive a signal representative of the reciprocal of the counted number.

Abstract: An input-output unit carries out some of the operations previously carried out in the microcomputer controlling the ignition, injection, etc. processes so that the number of bits in the microprocessor can be reduced. The input-output unit includes a counter which furnishes speed-dependent or angle-dependent signals. During a predetermined angle of rotation or while a particular speed-dependent value is counted and down, a frequency proportional to the quantity of air in the air inlet is counted, the resultant air number transferred to the microprocessor where it is modified. The modified air number can be counted down in the same counter which was used to count down the speed-dependent signals. The time required for counting down the modified air number determines the injection time and/or the closing time for an electronic switch in the primary circuit of the ignition coil.

Abstract: A system for providing acceleration enrichment in a vehicle engine fuel injection system is enabled by a sensed transition from a transmission neutral condition to a transmission drive condition to enrich the mixture supplied to the engine to provide improved engine performance.

Abstract: An electronic control apparatus for a fuel injection system in internal combustion engines which has a timing device for the generation of electric injection pulses, whose duration is dependent on operating characteristics and which are delivered to at least one electromagnetic injection valve which includes a time control circuit associated with the timing device in order to form at least one limiting value for the subsequent injection pulse and the subsequent injection pulse as well as the at least one limiting value can be delivered to a selector circuit so as to limit variations with respect to the duration of the injection signal thereby achieving smooth operation of the internal combustion engine.

Abstract: A method for producing trigger pulses in relation to a preset phase of motion proceeding with a continuously variable period, whereby pulses are accumulated, and at the same time two time intervals are successively determined within the fundamental time interval as the phase of the motion is changed by a preset value. The durations of these two time intervals and the sign of the difference between them are used to correct the number of stored pulses which are counted until a preset number is reached, which moment marks the onset of a trigger pulse. The device for effecting this method comprises a unit for determining the difference between time intervals and correcting the fundamental time interval, which is connected to a control unit, a main pulse counter and a main controlled frequency divider connected, in turn, to a pulse generator. The control unit is connected to a control pulse unit and an initial adjustment unit.

Abstract: A fuel feed device for an engine capable of electronically controlling the fuel feed rate corresponding to the suction air flow rate in the intake passage, comprising an air flow rate detecting device for generating electric signals of frequencies proportional to suction air rate, a plurality of electromagnetic valves disposed at a suitable position in the intake passage and adapted so as to permit supplying through a fuel pressure regulator the fuel of a fixed pressure differential with the suction pressure near a fuel outlet, and an electric control means for driving the electromagnetic valves with a shifted phase with one another to control the respective opening times thereof in accordance with the engine operating condition. Thus the accurate and highly reliable fuel supply is achieved over the wide range of engine operating condition from the idling to the maximum speed operation.

Abstract: An internal combustion engine function control system, for example a spark ignition control system, comprising first and second pulse generating means driven by the engine. The first pulse generating means produces a train of pulses at a first frequency equal to the frequency of the required function and the second pulse generating means produces a train of pulses at a second frequency which is a multiple of the first frequency. Engine parameter sensitive means are provided for varying the phase of the second pulse train relative to that of the first pulse train between limits such that the combined ordinal succession of the pulses is maintained constant. The system further includes function timing means for causing triggering of an output circuit at the end of a delay following a pulse from said first pulse generating means.

Abstract: An electronically-controlled fuel injection system for an internal combustion engine having odd numbers of cylinders, in which the quantity of fuel supplied to the engine cylinders is regulated by the duration of pulses of a fuel injection pulse signal applied to solenoid-operated fuel injection valves, and two fuel injection pulses are generated in each operating cycle of the engine in synchronism with the revolution of the engine. In the system, the frequency of an ignition signal generated by an ignition unit in the engine is doubled to provide an output pulse signal, and the frequency of sucn an output pulse signal is then divided by the number of engine cylinders so as to generate the fuel injection pulse signal in synchronism with this frequency-divided output pulse signal.

Abstract: A principal operational variable of an internal combustion engine, for example the fuel-air mixture ratio, is controlled by superposition of three separate control steps. The basic setting of a control variable is obtained with a relatively coarse forward control, for example a carburetor in the case of fuel-air mixture control. Superimposed on this basic control is a refined forward control step which is based on the prevailing magnitudes of at least one operational variable, preferably the engine speed and the throttle valve position, and which applies a multiplicative correction to the basic setting of the fuel-air mixture. The third superimposed control step is a feedback control of the fuel-air mixture within the range of correction applied by the second control steps but based on still another engine variable, in particular the exhaust gas composition as sensed by an oxygen sensor (.lambda.-sensor). After comparison with the reference signal, the .lambda.