Abstract: An electronically controlled fuel injection or feeding device for use in an internal combustion engine is disclosed. The device comprises means for storing respective engine speeds corresponding to respective positions of an accelerator pedal, and means for increasing the intake mixture of fuel and air to the engine corresponding to the engine speeds by a given amount when a decrease of the actual engine speed is detected under the condition wherein instant pedal position is not changed at a relatively low engine speed.

Abstract: A Karman vortex generator is disposed in the air intake passage of an internal combustion engine. The frequency of the Karman vortex generated by the generator is detected by a Karman vortex frequency detector to measure the flow rate of intake air. The frequency of the Karman vortex is in proportion to the flow rate of intake air with a Strouhal number being the constant of proportionality thereof. However, when the flow rate or the flow velocity of intake air is within a certain range, the Strouhal number fluctuates and the proportionality between the Strouhal number and the flow rate of intake air is broken. This range is shifted when the kinematic viscosity of intake air changes. The kinematic viscosity of intake air depends upon the temperature thereof.

Abstract: A method of measuring barometric pressure with a manifold pressure sensor (62) in a microprocessor based engine control system utilizes known engine operating conditions to interrogate the sensor. Also on engine turn-off, a power latch signal (158) is generated to delay power removal until the throttle valve (160) is driven open and the pressure sensor (62) is interrogated for its value. This value at this time is the ambient or barometric value of pressure. This value is stored in the microprocessor's (26, 28) memory (84, 86) and maintained by means of a standby voltage (80). During engine operation, the pressure sensor (62) is interrogated and value of the stored barometric pressure is changed by one unit of pressure if the stored and measured values are unequal.

Abstract: The present invention relates to an engine control device adapted to determine a basic fuel feed rate (Tp) in response to signals from a suction air flow rate sensor (20) and an air-fuel ratio sensor (20), and thereafter a fuel feed rate (Ti). According to the present invention, suction air flow rates (Q.sub.An-1, Q.sub.An-2) are calculated first on the basis of the last and the next to last fuel feed rates (Tin-1, Tin-2). The coefficients (A, B) required to correct the properties of the suction air flow rate sensor (20) are computed on the basis of these suction air flow rates. In the present invention, a fuel feed rate is determined finally on the basis of these coefficients.

Abstract: An apparatus and method for detecting an intake air mass flow rate using a Karman vortex air flow arranged in an intake passage of an internal combustion engine, in accordance with the formula:.gamma.(x)=.gamma.(760).times.V.sub.p (x)/V.sub.p (760)where .gamma.(x) is an intake air density to be obtained; .gamma.(760) is the air density under standard atmospheric pressure, V.sub.p (x) is the amplitude value of the analog signal obtained from the Karman vortex air flow sensor; and V.sub.p (760) is the amplitude value of the analog signal under standard atmospheric pressure.

Abstract: A single pressure sensor is provided to measure the air pressure in the intake manifold of a fuel injection engine. An electronic control unit having a microcomputer is provided to control the fuel amount and ignition timing in accordance with various engine parameters including the engine rotational speed and the intake pressure. The intake pressure is first measured before the engine is started so that the data of this pressure can be used as data indicative of atmospheric pressure. During operation of the engine, the pressure data may be used as normal intake pressure data. However, when the engine operates at a low speed and under high load, the pressure data is used as data indicative of the atmospheric pressure with slight correction.

Abstract: This system computes final fuel injection amount TAU on the basis of the following formula;TAU=A.times.TP+B+JwhereA : a first learning termB : a second learning termTP : basic fuel injection amountJ : correction amountLearning control is effected by correcting the second learning term B during idling periods and by correcting the first learning term A when an engine has larger than a predetermined load.

Abstract: A method for evaluating output signals of a sensor for measuring operational parameters of an internal combustion engine, utilizes characteristic wave forms of signal portions derived from a sensor. Threshold levels for setting the beginning and the end of an injection process are determined from threshold levels of an (n+m)th signal portion which are derived from a fraction of preceding nth signal. The device for carrying out this method includes a store for the peak value of the nth signal and a controlled discharging device which cooperates with a threshold switch and which is controlled by other parameters of the engine such as rotary speed.

Abstract: A method and system for controlling an amount of fuel supplied into an internal combustion engine.

Abstract: A method of detecting the ignition time point of an engine by detecting the ignition of the engine by the detection of the burning flame light of the fuel in the combustion chamber of the engine and by photoelectrically converting the burning flame light thus detected into an electrical signal so as to determine the ignition time point of the fuel, which comprises the steps of: (a) converting the burning flame light detected by the flame sensor into a voltage signal through photoelectric converting means; (b) applying said voltage signal to a comparator and comparing said electrical signal with a reference voltage; (c) varying said reference voltage in accordance with the running conditions of the engine; and (d) detecting the ignition time point from the resulting output signal from said comparator, and an apparatus for the same.

Abstract: In an electrical fuel injector which comprises an air flow meter for detecting an amount of air intake to an internal combustion engine, a revolution counter for measuring the rate of rotations of the internal combustion engine, and an electronic circuit adapted to arithmetically control an opening time of an injection valve for injecting fuel into the internal combustion engine based on output signals from both air flow meter and revolution counter, a digital filter is provided which has a coefficient variable in accordance with drive conditions of the internal combustion engine, so that the output signal from the air flow meter is applied to the electronic circuit through the digital filter.

Abstract: A fuel supply device for internal combustion engines comprising a computer having a memory which stores an air flow quantity characteristic related to a pressure difference between the up- and down-streams of a throttle valve, an air flow quantity to pass the throttle valve and the throttle valve opening degree. A throttle valve actuator is moved by the computer for controlling an air flow quantity to be supplied to an engine.

Abstract: A method is provided for the automatic control of the ignition time in a spark ignition engine or the injection time in a compression-ignition engine wherein at least one typical phenomenon of the running conditions of the engine, such as the occurrence of the peak pressure in the cylinder within a certain angular interval of the crankshaft, or the passage of the flame front through a reference position of the combustion chamber is detected, and the detected measurements have an aleatory character. This method comprises the determination of a statistical value representative of at least P validated measurements, of said phenomenon occurring during at most Q cycles, and the use of said statistical value to modify the control time of the combustion initiation so that said statistical value takes a predetermined value corresponding to the desired running conditions.

Abstract: In a method wherein a fuel injection time duration is allowed to perform a proportional-plus-integral action by the use of an air-fuel ratio feedback correction coefficient obtained from the output of an O.sub.2 sensor thereby to control an air-fuel ratio to a target air-fuel ratio, a correction value for allowing a mean value of the air-fuel ratio feedback correction coefficient to approach a predetermined value is varied every time the air-fuel ratio feedback correction coefficient skips a plurality of times, thereby to learn-control the air-fuel ratio of an air-fuel mixture to be a stoichiometric one.

Abstract: There is disclosed an internal combustion engine in which synchronous fuel injection is conducted at every predetermined crank angle and an asynchronous fuel injection is conducted regardless of the crank angle. The engine is provided with an electronical control circuit which computes a quantity of fuel to be injected in each synchronous fuel injection on the basis of a load applied to the engine and an engine speed. A variance of intake pressure in said engine is computed. The computed variance is compared with a reference level which is determined to be greater as the intake pressure becomes higher. In the case of detection of the variance of the intake pressure being greater than said reference level, said quantity of fuel to be injected is increased.

Abstract: An electronic fuel injection control includes a main fuel control circuit, a transient enrichment control circuit temporarily increasing fuel flow as a result of increasing of a demand signal, and temperature compensation means non-linearly varying the effect of the enrichment control with engine temperature. The temperature compensation means preferably includes a temperature "window" detector which acts to increase the effect of the enrichment control whenever the engine temperature is between prescribed limits.

Abstract: The output of a fuel pump of an internal combustion engine is controlled by the duty cycle of its power supply circuit, which is in turn controlled in accordance with engine and fuel conditions. Sensor signals indicative of the engine and fuel conditions are processed to derive a DC voltage level suitable to the conditions. The derived voltage and a triangular voltage signal of fixed frequency and amplitude are compared by a comparator which outputs a train of pulses. The frequency of the pulse train is that of the triangular wave and the duty cycle thereof is determined strictly by the derived voltage. The pulse train from the comparator is amplified to drive the fuel pump.There may be many different kinds and combinations of engine and/or fuel condition sensors. In addition, sensor signal processing to derive the DC voltage level may take a number of different forms and may include feedback from the fuel pump power supply circuit in order to suppress transient fluctuations.

Abstract: In an internal combustion engine provided with a hot-wire air flowmeter and a canister for supplying fuel evaporated from a fuel tank into an intake passage, there exists a state where an excessively-rich mixture is supplied from the canister to the intake passage because of trouble of the canister and therefore engine stops. If the hot wire is heated in such a state as described above for removal of contaminations sticked onto the hot wire after an ignition switch has been turned off, there exists a problem such that rich mixture may be fired by the heated hot wire. To overcome this problem, an engine stop detecting means is additionally provided in order to inhibit the hot-wire from being heated up when the ignition switch is turned off after engine stop. That is, the hot wire is heated only when the engine is running before the ignition switch is turned off.

Abstract: The engine speed is periodically detected at every predetermined crankshaft angles for obtaining a plurality of engine speed data whose number equals an integral multiple of the number of cylinders of an internal combustion engine. Either maximum or minimum values among the plurality of engine speed data is determined, and such operations are repeated for a duration covering all power strokes within all the cylinders, thereby obtaining a plurality of sets of engine speed data. Then the order of engine speed data giving the maximum or minimum value within each set is obtained, and majority decision is effected to determine which order of data gives the maximum or minimum most frequently throughout all the sets. The difference between the maximum and minimum values is obtained for each set, and the amount of fuel to be supplied to the engine is controlled so that the difference becomes common to all the cylinders.

Abstract: The fuel supply to an internal combustion engine is controlled by fuel injection signals that depend on the intake manifold pneumatic pressure PM and the engine running speed NE. The basic pulse width TP of the fuel injection signal is calculated from the equation TP=(TPBSE+TPNE)TPKNE, where TPBSE is taken from a one-dimensional function table PM-TPBSE, TPNE is taken from a one-dimensional function table NE-TPNE, and TPKNE is taken from a one-dimensional function table NE-TPKNE.

Abstract: A control mechanism for a fuel metering system in a combustion engine is proposed which makes possible a start control defined as load-independent or as nearly load-independent. It is the purpose of the control mechanism to avoid possible false interpretations of the load signal during extremely low rpm. The control mechanism comprises a function generator which, dependent on operational characteristics, determines or co-determines the signal at the load input of a signal processing stage of the fuel metering apparatus during start-up.

Abstract: A method comprising correcting the air/fuel ratio of a mixture being supplied to an internal combustion engine, by the use of a correction coefficient determined as a function of detected values of atmospheric absolute pressure and intake pipe absolute pressure. A device is also provided, which includes means for arithmetically calculating the correction coefficient as a function of outputs of sensors for sensing the two kinds of absolute pressure or means storing predetermined values of the correction coefficient for selective reading as a function of the sensor outputs, and means for correcting the valve opening period of a fuel injection valve by the calculated or read coefficient value.

Abstract: An electronic control fuel injection system for a spark ignition internal combustion engine is described wherein air flow rate is controlled as a function of fuel flow rate by transmitting an operator's depression stroke of an accelerator pedal to a fuel selecting mechanism, applying a signal representative of the selected fuel flow rate to a computer which determines the optimum air flow rate, thereby controlling the opening of a throttle valve to provide it. Within the computer, the relationship of the accelerator pedal movement to actual fuel flow command is varied in a predetermined manner to provide a desired engine response characteristic. Thus, the drive feeling for a vehicle can be varied within a range from normal to either a faster or more conservative engine reaction.

Abstract: Fuel supply to an internal combustion engines is controlled in accordance with the intake manifold pneumatic pressure and with engine running speed. The fuel supply is corrected in accordance with the outer air temperature and with the temperature corresponding to an air intake passage temperature so that the changing rate of fuel supply with respect to the change of the outer air temperature increases to when the temperature corresponding to the intake passage temperature decreases.

Abstract: In the control of fuel injection in an internal-combustion engine, whether or not the rate of change of the engine rotational speed exceeds the selected limit of the rate of change of the engine rotational speed, determined by the ratio of the engine rotational speed to the automobile speed and the ratio of the intake air amount to the engine rotational speed, is checked. The value of the engine rotational speed used in the control of the fuel injection pulse width and the ignition timing is restricted to within the selected limit of the rate of change of the engine rotational speed.

Abstract: A fuel quantity measuring apparatus, preferably for a Diesel engine, is proposed in which the course of the fuel pressure is evaluated. A specialized pressure gradient of a first polarity marks the onset of supply or injection, and the maximum of the pressure gradient of the other polarity represents the end of injection or supply. The question of which designation prevails, whether injection onset and end or supply onset and end, is determined by the measurement location, that is, whether it is in the direction of the injection valve or in the direction of the supply element of the fuel supply pump. The injection quantity, for example, may be determined via the integral of the pressure during the metering period. It is recommended, when a piezoelectric pressure receptor is used, that a resistor-capacitor element be switched parallel thereto.

Abstract: An electronic ignition pulse generator for internal combustion engines comprising an angle-of-rotation pulse giver feeding a succession of angle pulses and a cycle signal to an ignition point computer and featuring a novel adjustment pulse generator with a binary counter controlled by the cycle signal, by a pressure transducer, voltage comparator and RS flip-flop gate, to count angle pulses, until the count corresponds to the pressure level in the engine intake duct, thereby producing a pressure-reflective adjustment count for the computer. A throttle switch at the carburetor blocks the counter during closed-throttle operation.

Abstract: An internal combustion engine fuel injection control apparatus is disclosed in which a basic fuel injection signal for light load is calculated as a function of the manifold pressure when the engine is operating with a light load, and a basic fuel injection signal for heavy load is obtained with the revolution number and the throttle valve position as the parameters when the engine is operating with a heavy load. The engine load condition (light or heavy) is decided in dependence upon the throttle valve position or the manifold pressure. The circuit employed for switch-over from a heavy load to a light load or vice versa preferably has a hysteresis characteristic.

Abstract: A fuel injection control apparatus having a pressure detection device for detecting pneumatic pressure in an intake manifold of an internal combustion engine comprises a pressure transducer and a low-pass filter, electrically connected to the transducer, for transmitting an electrical signal from the transducer below a cutoff frequency which is determined to be a frequency equal to or lower than 40 Hz.

Abstract: In an internal combustion engine having an amount of fuel injection controlled in relation to pressure in an intake pipe, a low pass filter is connected to the output side of an intake pipe pressure sensor so as to remove a pulsating component of the intake pressure. A second low pass filter is provided so as to compensate for the delay in response of such filter, and the outputs of both filters are calculated by a calculating unit.

Abstract: The invention contemplates engine shut down protection apparatus used in conjunction with an electronic fuel injection circuit for a water cooled internal-combustion engine. When turning off water-cooled internal combustion engines equipped with typical electronic fuel injection systems both the fuel supply and the ignition circuit are disabled. As the engine speed decreases the engine block cools faster than the pistons since the block is water cooled and this uneven cooling may result in damage when the engine is shut down at high speed. The instant invention maintains the fuel supply to the pistons after engine shut down to cool and lubricate the pistons and prevent possible engine damage.

Abstract: An exhaust gas recirculation control valve is positioned by a diaphragm responsive to the difference between a control pressure and atmospheric pressure. The control pressure is adjusted so that its absolute value is maintained equal to a command which varies with engine operating conditions, whereby exhaust gas recirculation is reduced automatically upon a decrease in atmospheric pressure.

Abstract: An electronic control device for an automobile is equipped with a circuit for producing a first reset pulse when power is initially supplied to the electronic control device, and a circuit for producing a second reset pulse when the engine is cranked by a starter motor. Thus, an electric digital computer in the electronic control device is initialized in response to not only the first reset pulse but also the second reset pulse.

Abstract: Disclosed is a fuel supply control system for controlling fuel amount to be supplied to an internal combustion engine including a sensor means for detecting engine load condition and other control parameters and generating sensor signals, an arithmetic means for determining a basic pulse width of a pulse signal indicative of basic fuel amount to be supplied, a means for correcting the basic pulse width of the pulse signal corresponding to various control parameter respectively indicative of engine conditions such as engine coolant temperature and a means for distinguishing engine driving condition based on inputs one of which is sensor signal indicative of engine load condition and generating correction command indicative of correction coefficient. The correction command is applied to the correction means to effect the same to increase or decrease the pulse width of the pulse signal or shut off the fuel supply to the engine.

Abstract: An electronically controlled fuel injection method for controlling a fuel injection valve of an intake system by electric signals characterized in that: from an input level X.sub.n-1 to be fed into a computation section from sensors at a previous fuel injection rate computation time T.sub.n-1, an input level X.sub.n to be fed into the sensors at a present fuel injection rate computation time T.sub.n, a delay time until a physical amount to be detected reaches an input point in the computation section by way of the sensors, and a time A.sub.n at which a cylinder to which a fuel is supplied by an amount based on the present fuel injection rate computation reaches a bottom dead center on a subsequent intake stroke, the following equation is computed; ##EQU1## and, C.sub.n is used as data on the physical amount for executing a present fuel injection rate computation.

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: The data processing system generally comprises a CPU, one or more memory units and an input unit. The input unit is capable of discriminating between signals contaminated with noise and noise free signals. Only noise free signals are stored for processing by the CPU. In one embodiment, the input unit determines whether an input signal value is within a predetermined range. If the signal value is within the range, it is stored. If the signal value is outside of the range, the input unit operates to determine the difference between successive values of the signal. If the difference between successive sequential values does not vary beyond a predetermined range for a predetermined time, the signal is regarded as being correct and the present value is stored for processing by the CPU. Otherwise, a preceding value is stored for processing by the computer.

Abstract: Internal combustion engines utilizing conventional carburetors have auxiliary devices such as a choke and accelerator pump which cause over-rich mixture and consequently affect the fuel consumption and exhaust gas emissions adversely. The present invention improves the performance of such engines whilst retaining the advantages of conventional carburetors.The invention provides a spark ignition carburetor equipped engine with an electromagnetic injection valve disposed in the induction manifold for the supply of additional fuel when required. Actuation means for the electromagnetic injection valve are preferably electronic devices which comprise a pulse generator and measured valve transmitter (sensors) for each of the engine operating parameters relevant to the injection of additional fuel, thus the timing and duration of opening of the injection valve is controlled precisely.

Abstract: In a control system for an internal combustion engine which receives a signal representing an operational parameter of the engine, a signal processor is disclosed which eliminates spurious signals. The processor comprises a memory which stores a plurality of sequential values of the signal, and an averager which averages at least some of the stored values and outputs the average as an output signal.

Abstract: A control system for an internal combustion engine comprises a transducer for issuing a signal representative of combustion pressure in a combustion chamber, a unit consisting of a bandpass filter and a wave-form shaping circuit for issuing a signal representative of existing combustion timing of the combustion chamber by processing the signal from the transducer for detection of rapid increase of the combustion pressure; a reference timing circuit for issuing a signal representative of a predetermined reference combustion timing of the combustion chamber in accordance with operation modes of the engine, a comparator circuit for issuing a signal representative of a difference between the signal from the unit and the signal from the reference timing circuit, and a unit consisting of a discriminating circuit and an actuator driving circuit for controlling the ignition timing, the air-fuel ratio of air-fuel mixture and the amount of exhaust gas recirculated into the intake system of the engine, by processing the

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: The invention contemplates an electrical network associated with a throttle-control potentiometer whereby a standard commercially available linear potentiometer having an given angle of electrical-resistance variation may be employed, over an entire lesser angle range of throttle rotation, to provide an output voltage which, for an initial fraction of throttle displacement, is a predetermined substantially linear variation of a given input voltage, and which, for the remaining fraction of throttle displacement, remains substantially constant at the level of the upper end of the linearly varying fraction. A feature of the invention is that the slope and extent of linear variation are selectable, without modification of the linear potentiometer.

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 motor vehicle combustion engine has exhaust apparatus including a sensor for sensing exhaust content therein and fuel control apparatus determining fuel supply to the engine in accordance with an engine operating condition and a trimming factor which is a function of the engine operating condition, the values of the trimming factor corresponding to different values of the engine operating condition being chosen to help maintain a predetermined exhaust content. The engine and fuel apparatus are characterized by a transport delay between the time a change is initiated in fuel supply and the time a resulting change in exhaust content can be sensed.

Abstract: A warm-up regulator device for enriching the air-fuel mixture delivered to an internal combustion engine during the engine warm-up phase, said engine having a fuel-metering system with a switching arrangement for generating metering signals in response to a group of engine operating parameters, a compensation stage for correcting the metering signals and a fuel-metering means, wherein the compensation stage is connected to a function generator for producing a signal which is speed-responsive to compensate for condensation losses in the walls of the fuel lines and engine when the engine is cold thus optimizing the operation of the engine. Also disclosed are several ways for reducing the compensation for condensation losses at higher speeds to prevent a negative affect on the exhaust gases and to match the regulator to various engines.

Abstract: A hybrid electronic control unit for regulating the air/fuel ratio of an internal combustion engine is disclosed. The electronic control unit is divided into two functionally distinct parts including an analog function generator and a digital function generator. The analog function generator receives analog signals to process efficiently by analog scaling, amplification, multiplication, and division while the digital function generator receives digital and logic inputs to process efficiently by addition, subtraction, and comparison. The analog function generator interfaces with the digital function generator by an analog signal from a D/A converter and other unconverted digital output signals from the digital function generator. Preferably, the analog function generator provides an open loop air/fuel ratio calibration based upon a speed density calculation including special condition corrections to the base calibration.

Abstract: An electronic control unit for regulating the air/fuel ratio of an internal combustion engine is disclosed. The electronic control unit has an open loop calibration for regulating the air/fuel ratio that is corrected with a closed loop correction signal developed by an integral controller. The open loop calibration is a speed-density based schedule which is combined with corrections for special conditions to account for the operating parameters of the engine at any instant. Included in these special condition corrections are provisions for an altitude compensation feature. The altitude compensation feature includes circuitry to modify the intake manifold pressure portion of the speed density schedule with two variables which depend on altitude.

Abstract: A fuel injection system employing digital logic to generate injection command pulses of a time duration calculated to provide a precise quantity of fuel to meet presently existing, varying engine requirements is disclosed herein. The system employs a first or injector selection circuit operative to select an injector or injector group for injection and a second or adaptive delay circuit to generate an injection command. The circuits are electronically intercoupled to provide for substantially simultaneous application of the selection pulse and injection pulse to the proper injector group and to eliminate the need for a mechanical distributor arrangement to select the proper injector group. The time duration or delay signal is generated by a function generator producing an output as a known function of time with injection occurring during the time it takes for the output to reach a pre-determined, selected, threshold value.