Abstract: An engine controller comprising a means for estimating an amount of the air flowing into the cylinder of the engine. The estimation means calculates the intake air amount mc(k+1) in the following equation determined from the physical model describing the law of conservation of mass for the intake air:mc(k+1)=.alpha..multidot.Q/.omega.+.beta..multidot.mc(k)where .alpha. and .beta. are constants, mc(k) is the last estimated value, Q is the flux of the detected air, and is the engine speed. The estimation is executed synchronously with the intake stroke so as to control the fuel injection amount synchronously with the intake stroke. To further improve the accuracy of the fuel injection even when the running condition of the engine changes after the estimation of the intake air amount, the fuel should be injected asynchronously with the intake stroke. We also disclose the engine controller that controls the amount of such an asynchronous injection.

Abstract: An engine control system has a CPU (central processing unit), a ROM (read-only memory) and a RAM (random-access memory) backed up by a power supply. Only in the case where the difference between the data in the RAM and that in the ROM is within a predetermined range will the engine control inputs be regulated by use of the data in the RAM.

Abstract: A scale pulse signal is produced whenever a revolution sensor detects a unit revolution angle formed an angle between cogs of poles. A time interval between the scale pulse signal is affected by an error in the formed angle. The time interval between the scale pulse signals can be corrected by using a correction coefficient detrmined by an actual value of the unit revolution angle detected by the revolution sensor and by a design value of the unit revolution angle, so that the time interval corresponds to the design value of the unit revolution angle.

Abstract: A code system for a device (30) that exhibits an input-output relationship characterized by an off-set and substantially linear performance (gain) comprising a resistor network (20) in cirucit with the device's coil (22), indicative of the device's GAIN and OFF-SET wherein the values of GAIN and OFF-SET are intrinsically coded within the value of a single resistor.

Abstract: Engine control apparatus for use in passenger cars and other applications includes a special calibration of the intake mixture preparation system. Although this calibration duplicates the optimum calibration for use with a continuously variable transmission (CVT), the apparatus instead includes, for reasons of practicality, a discrete-ratio powershift transmission. Also included is a feedback control system which dispenses with the conventional mechanical connection between accelerator pedal and engine throttle valve. This drive-by-wire control system operates the engine as closely as is practical to the optimum CVT engine operating schedule, a predominantly wide-open-throttle engine operating schedule. The overall combination of special engine calibration and drive-by-wire control with a discrete-ratio transmission can offer the majority of the fuel economy advantage available with a CVT.

Abstract: A method of controlling a plurality of electrical devices which control an operation of an internal combustion engine wherein an operation period of time required for each of the electrical devices is computed by computing means in response to operating conditions of the engine, the computed required operation period of time is counted by time-counting means, and each of the electrical devices is caused to operate during the counting. At each start of the time-counting from the computing means, a different one of the electrical devices is selected and the operation thereof is started, an interrupt signal is generated when the time-counting means has counted up, and the operation of the selected different one of the electrical devices is deenergized in response to the generation of the interrupt signal. Preferably, the time-counting means comprises a signal time counter.

Abstract: A basic injection quantity is determined by engine speed and pressure in an intake passage of an engine. The pressure is estimated from engine speed and throttle position. A transient state such as acceleration of the engine is detected. When the transient state is detected, the estimated pressure is selected, and the basic injection quantity is determined based on the estimated pressure.

Abstract: A fuel supply control system introducing the feature of learning in assuming or projecting an intake air flow rate while an engine driving condition is maintained in a sonic flow range, in which intake air path area is maintained substantially constant and intake air flow rate is varied linearly according to variation of an engine speed. The system also detects the engine driving condition in the sonic flow range and the engine speed maintained substantially constant to derive a basic fuel supply amount on the basis of boost pressure. The assumed intake air flow rate is derived on the basis of the basic fuel supply amount and the engine speed. The system derives the basic fuel supply amount on the basis of the assumed intake air flow rate and the engine speed when the engine speed varies within the sonic flow range.

Abstract: The quantity of air induced in a cylinder of an engine is estimated by using equations based on various coefficients. The coefficients are stored in a memory and derived in accordance with engine operating conditions. The estimated quantity of induced air is corrected so as to approximate quantity of air actually induced in the cylinder. A basic injection pulse width is calculated based on the corrected air quantity. The basic injection pulse width is corrected by a feedback coefficient, thereby producing a fuel injection pulse width signal for operating a fuel injector of the engine.

Abstract: An engine control apparatus comprises a throttle sensor, a pressure sensor for detecting a pressure in the intake manifold of an engine as a value of the absolute pressure, an engine revolution speed detector, a zone detector for detecting the fact that a signal value indicating a degree of opening of a throttle valve and a signal value indicating an engine revolution speed fall in a predetermined atmospheric pressure detection zone and a processing unit to calculate a value of atmospheric pressure by adding a set value to a signal of pressure upon detecting said values being in the detection zone. A timer may be provided to detect the fact that the signal values of the degree of opening of the throttle valve and the engine revolution speed are continuously in the atmospheric pressure detection zone for a predetermined time.

Abstract: In order to obviate the delay between a demand for transitory engine operation and the injection of the appropriate amount of fuel, an initial correction pulse width is generated in response to the change in throttle valve position is added to a basic width which is developed based on the output of an air flow meter located in an upstream section of the induction conduit. The system further provides for continuously updating correction factors which are applied to the throttle sensor to ensure linearity and generating weighting factors and the like which are appropriately applied to improve the air-fuel control.

Abstract: An internal combustion engine control device is constructed to estimate an engine air intake quantity based on an engine speed when the engine is running in an intake air pulsation generating range to control the engine in accordance with the air intake quantity thus estimated. The estimated air intake quantity is corrected by a correction value which is related to the density of the intake air.

Abstract: An engine control method for a vehicle is disclosed in which operation of an engine is optimally controlled in an entire operating range thereof without causing any undesirable delay in control operation. To this end, operating conditions of the engine are sensed through the use of various sensors and control signals are calculated based on the sensed engine operating conditions in a plurality of steps through the use of a microcomputer so that the operation of the engine is optimized by the use of the control signals thus calculated. In one embodiment, a first step and a second step of the plurality of steps are alternately calculated and omitted every other time the control signals are calculated while an operating parameter of the engine operates in a specified operating range in which variations in the sensed operating conditions of the engine are limited.

Abstract: A fuel supply control system derives a basic induction volume efficiency on the basis of an intake air pressure and modifies the basic induction volume efficiency with a correction value which is derived on the basis of an engine revolution speed and the intake air pressure. An induction volume efficiency is derived on the basis of modified basic induction volume efficiency, which derived induction volume efficiency is used for deriving a basic fuel supply amount with the intake air pressure. The basic fuel supply amount thus derived is used for controlling fuel supply for the engine. Derivation of the basic induction volume efficiency is performed by an interrupt routine which may be executed in a predetermined timing derived depending upon a time or in synchronism with engine revolution cycle. The correction value may be derived in a background job.

Abstract: A microcontroller having two internal timers is used to calibrate the engine rpm and wheel speed signals of a vehicle and to time the output periods of these signals, which are transmitted to, for example, digital rpm and speed indicators.

Abstract: The fuel injection quantity required for maintaining the air-fuel ratio of the mixture supplied to each cylinder of an engine at a desired value is determined by a deposition rate X at which injected fuel deposits and forms a film mass on an intake manifold wall of the engine and a vaporization rate 1/.tau. at which the film mass vaporizes from the manifold wall, a current film mass quantity M.sub.f determined from the calculated X and l/.tau. and the fuel quantity by the preceding injection, a desired fuel quantity Q.sub.a /(A/F) to be supplied air-fuel ratio A/F in accordance with the following equation ##EQU1## an air-fuel ratio feedback correction factor .gamma. aiming at a stoichiometric air-fuel ratio based on a signal generated by an O.sub.2 sensor is calculated and an actual quantity of fuel corresponding to G.sub.f .multidot..gamma. is injected. A film mass quantity in a current computing cycle is based on the film mass quantity calculated during the previous computing cycle.

Abstract: A control system for an internal combustion engine comprises an engine speed sensor, a section for producing a feedback correction value in accordance with a difference between speed of the engine detected by the engine speed sensor and a target idling speed when the engine is in a specific idle operation, a section for producing a learning control correction value based on the feedback correction value and storing the produced learning control correction value in a memory to renew a stored learning control correction value, a section for the performing a feedback control for the speed of the engine with the feedback correction value and the learning control correction value combined with a fundamental control value to keep an actual idling speed of the engine at the target idling speed, an air-fuel ratio sensor, a section for performing a feedback control for an air-fuel ratio of a fuel mixture in accordance with an detection output of the air-fuel ratio sensor, a section for detecting malfunction of the air

Abstract: As engine control apparatus for electrically controlling a fuel and ignition timing for a multicylinder 4-cycle engine comprises a plurality of first micro-computer each being provided for every one of or for every pair of cylinders in which compression and exhaust strokes are in phase, and a second micro-computer which is arranged to communicate with each first micro-computer. The first micro-computer calculates a fundamental quantity of fuel injection from a rotational signal and a load signal of the engine, a correction quantity according to correction control information from the second micro-computer, and controls the operation of a fuel injection valve, the ignition timing from the rotational signal and load signal, a correction quantity according to correction control information from the second micro-computer, and controls the on/off operation of ignition coils according to the ignition timing.

Abstract: The quantity of air inducted in a cylinder of an engine is estimated by using equations based on various coefficients. The coefficients are stored in a memory and derived in accordance with engine operating conditions. A basic injection pulse width is calculated by the estimated inducted air quantity and speed of the engine. The basic injection pulse width is corrected by a feedback coefficient, thereby producing a fuel injection pulse width signal for operating a fuel injector of the engine.

Abstract: The resistance to supply voltage, e.g. battery, fluctuation of an input/output circuit for a control system, e.g. vehicular ignition/fuel injection system, is improved by placing a comparator K in each analog input line, and using a voltage divider UD to compensate the reference voltage U.sub.R applied to one of the comparator inputs. Processing speed is increased by using digital comparators 22-26, which test not only for threshold value equal to counter state, but also for threshold value greater than counter state, in the duty-cycle modification circuit. Chip count is reduced and integration is increased by using a single voltage divider to supply all the input comparators and by using a High-Speed Output (HSO) port on the central processing unit (CPU) to perform multiple output tasks.

Abstract: A system and method for controlling quantity of fuel injected to an internal combustion engine are disclosed in which a characteristic having a correlation to part of fuel supply quantity from an injector which has been supplied toward a wall surface of an intake air passage of the engine has been adhered onto the wall surface and will be brought away from the wall surface into a combustion chamber during a suction stroke at the present fuel injection timing is derived so that a correction quantity for a quantity of injected fuel is calculated on the basis of the derived characteristic. Therefore, an air-fuel mixture ratio when the engine falls in a transient state is not deviated from a target air-fuel mixture ratio so that an exhaust gas emission characteristic can be improved.

Abstract: A method for feedback controlling an air/fuel ratio of mixture supplied to an internal combustion engine to a target air/fuel ratio, which uses an output signal of an oxygen concentration sensor. The sensor's output signal is proportional to the oxygen concentration in the exhaust gas of the engine. When the target air/fuel ratio is set at a stoichiometric air/fuel ratio, the air/fuel ratio of the mixture is varied by a small amount around the stoichiometric value if the air/fuel ratio of mixture supplied to the engine is detected to be in a predetermined air/fuel ratio range which includes the stoichiometric air/fuel ratio. The determination of the air/fuel ratio is calculated from the output signal of the oxygen concentration sensor.

Abstract: An air/fuel ratio control system employs an altitude dependent learnt uniform correction coefficient which is applicable for all engine driving range and another engine driving range based correction coefficient learnt with respect to responsive engine driving range. The uniform correction coefficient is cyclically updated on engine driving range based correction coefficient. The control system performs FEEDBACK mode air/fuel ratio control with the learnt uniform correction coefficient and the engine driving range based correction coefficient. On the other hand, the control system performs OPEN LOOP mode air/fuel ratio control with the learnt uniform correction coefficient.

Abstract: A fuel adhesion percentage of an injected fuel to a surrounding portion of an intake valve is determined in accordance with a fluctuation value of an air-fuel ratio correction coefficient and a fluctuation value of a signal of an air-fuel ratio detecting sensor or a signal of an oxygen amount detecting sensor. Each adhesion percentage of the injected fuel is divided and stored in each division area of a characteristic memory map of a control unit. The adhesion percentage of the injected fuel is stored in a memory of the control unit and is determined in accordance with present throttle valve opening degree and present engine coolant temperature by the characteristic memory map. The adhesion percentage of the injected fuel is obtained through a learning control process in the control unit. An air-fuel ratio correction in a transient period is carried out smoothly.

Abstract: A fuel injecting amount of an internal combustion engine is calculated utilizing equations determined from a physical model describing a behavior of fuel in the engine. The fuel injection system includes estimation means in which estimation values fw and fv of the adhering fuel amount and the vapor fuel amount respectively are calculated based on: a product .lambda.r.multidot.m of the detected fuel/air ratio and the detected air amount; a division Vf/.omega. of fuel evaporating amount by the engine speed; and a fuel injecting amount q. The fuel injecting amount is calculated in the system based on the division Vf/.omega., the estimated values fw and fv, the product .lambda.r.multidot.m, and a summed up deviation from a target ratio. The coefficients of respective terms are determined by analyzing the physical model by modern control theory. A variation of the invention does not use an air/fuel ratio sensor.

Abstract: An encoder delivers a pulse input signal in phase with equal angular steps of a rotary component, such as a toothed wheel driven by the crankshaft of an internal combustion engine. A missing tooth defines a reference position at which a synchronizing signal is also delivered. A counter is incremented by the pulse input signal and is reset by the synchronizing signal. A comparator compares the count in the counter with a number in a memory circuit to deliver a signal for triggering an event when the count in the counter coincides with the number in the memory circuit. The counter comprises a first counting circuit providing the least significant outputs of the counter and a second counting circuit providing the most significant outputs. The first counting circuit is reset by the input signal, and the second counting circuit by the synchronizing signal.

Abstract: Fuel injection is started through a first one of fuel injection valves, and a time counter counts a period of time elapsed from the start of fuel injection through the first one valve. Fuel injection is started through a second one of the fuel injection valves when a predetermined period of time elapses after the start of fuel injection through the first one valve. The fuel injection through the first one valve is terminated in response to completion of counting of the time counter, and the time counter is restarted to count a difference between a desired fuel injection period of time for the first one valve and a desired fuel injection period of time for the second one valve. The fuel injection through the second one valve is terminated in response to completion of counting of the restarted time counter.

Abstract: In an engine control system which determines the amount of fuel to be injected on the basis of an intake pipe pressure detected downstream of a throttle valve and engine speed (D-EFI), fail-safe action is provided when a failure of an intake pipe on the downstream side of the throttle valve is detected. The fail-safe apparatus of the present invention is designed to signal the occurrence of an abnormality with the intake system when the throttle valve is not being opened, that is, the throttle valve is stationary or is closing, a vehicle speed variation exceeds its specific value and the engine speed exceeds its specific value. When these conditions are detected, engine power is controlled lower, thereby assuring vehicle driving safety.

Abstract: In order to control all revolution numbers of an engine at high precision, combustion of each cylinder is reliably controlled. For the combustion control of each cylinder, there are controlled measurement timings of an air volume as well as a fuel volume contributive to the combustion and exhaust gas being a combustion result, calculation timings of a fuel injection volume and an ignition timing, and output timings of fuel injection and/or ignition. These timings are synchronized by crank angle positions form a reference point such as top dead center. Particularly as to the measurement timing, a delay time of a gas stream between a measurement spot and the cylinder is compensated in terms of a crank angle corresponding thereto, whereby the variables to be measured are synchronized.

Abstract: An electronic control device in an internal combustion engine with an EGR apparatus for calculating a predetermined control variable such as a fuel injection time period or an ignition timing, and correcting same to exclude a component stemming from EGR gas in the intake air. The device comprises a first unit for calculating a fundamental value of the fuel injection time period (TP), a second unit for converting the detected intake pressure under the detected atmospheric pressure into a converted intake pressure under the standard atmospheric pressure in response to the detected atmospheric pressure and a third unit for calculating a correcting value (TPE) from data including information regarding the EGR gas under the standard atmospheric pressure and stored as a function of the converted intake pressure (PMT). In this device, the fundamental value can be corrected by subtracting the correcting value from the fundamental value in the case of the fuel injection time period.

Abstract: Disclosed is an electronic learning control apparatus for an internal combustion engine, in which a basic control quantity corresponding to a target control value is corrected and computed by a feedback correction value to determine a control quantity and an objective parameter to be controlled is controlled by a static control quantity through control means. The entire deviation of the feedback correction value from a predetermined reference value is separated into deviations for respective error causes according to predetermined analysis rules, and a learning correction value for each error cause is computed according to the separated deviation for each error cause, and the basic control quantity is corrected based on the learing correction value for each error cause to obtain a final optimum control quantity. In this apparatus, the learning speed is increased and the learning correction precision can be improved.

Abstract: A pulse encoder has a motor detecting portion (1) which detects a motion of an object whose position should be measured and which outputs a signal having information regarding the motion. A clock generator (3) outputs a clock pulse. The pulse encoder processes the information regarding the motion synchronized by the clock pulse. The pulse encoder includes a clock malfunction detecting portion (4) which receives the clock pulse and at least a part of the signal having information regarding the motion showing whether the object, whose position should be measured, has moved or not. The clock malfunction detecting portion outputs a clock malfunction signal when motion is detected by the part of the signal having information showing whether the object has moved or not, when the clock pulse is not output.

Abstract: An electronically-controlled fuel injection system for an internal combustion engine including means including a computer for electronically controlling a fuel injection quantity of an engine, means for detecting a rotational speed of the engine and a throttle sensor having lower and higher opening regions for detecting an opening of a throttle valve is further provided with means for storing the ratio between the slopes of output voltage characteristic curves derived from the regions with respect to a throttle opening in a range where the ranges of throttle openings to be detected in the regions overlap, and means for correcting the output voltage generated from one of the regions by use of the ratio in a throttle opening range exceeding said overlapping range.

Abstract: An in-engine deposit detection apparatus for an engine control system is disclosed, comprising a sensor for detecting the output air-fuel ratio of the exhaust gas, a device for controlling the fuel supply amount according to the output air-fuel ratio from the sensor, acceleration detector for detecting a time point when an acceleration command is given the engine, a device for measuring a value based on the time length from a command time point detected by the acceleration detector to a time point that the sensor detects the shift of the output air-fuel ratio to rich side, a device for giving a reference value defining a limit of a normal range of the measurement obtained on the basis of the time length from the command time point detected by the acceleration detection means to the time point when the sensor detects that the output air-fuel ratio has shifted to rich side, and a device for comparing the measurement from the measuring means with a reference and deciding that there exists a deposit having an adv

Abstract: A fuel injection system of an internal combustion engine in which the fuel injection amount is controlled corresponding to an atmospheric pressure change by utilizing an altitude compensating learning correction factor stored in a backup RAM. Even thought a battery is disconnected from the memory of the backup RAM and the stored data of the learning correction factor is lost, the altitude compensating learning correction factor is directly determined based on the atmospheric pressure without executing learning control so that the fuel injection amount is corrected at the time of the initial cranking of the engine.

Abstract: A quantity of fuel supplied to an engine so as to allow the air-fuel ratio of a gas mixture to be a target air-fuel ratio is subjected to a feedback correction based on an air-fuel ratio sensor. At the time of the feedback correction, a learning correction is also conducted on the basis of a learning value that is calculated in accordance with a feedback correction value. When the learning value to be used for the learning correction is altered, the feedback correction value is initialized. An initialized feedback correction value is an addition of the feedback correction value before the alteration to a deviation of the respective learning values before and after the alteration of the learning values.

Abstract: A fuel injection control system for controlling the amount of fuel to be injected to an internal combustion engine. The fuel injection control system consists of a control unit arranged to calculate the fuel injection amount in accordance with a standard injection amount corrected with a transient correction amount. The transient correction amount is calculated in accordance with a difference value and a correction coefficient which is previously set in accordance with engine operating condition. The difference value is of between an equilibrium amount of adhering and floating fuel in steady state in an intake system and a predicted variable of amount of the adhering and floating fuel at a predetermined point of time.

Abstract: A learning map on which the rewriting of data is performed in accordance with the results of an internal combustion engine controlling operation is provided. When the number of pieces of data written in this learning map has become greater than one, the corresponding weighting is done for each unlearned region in the basis of the learning data on the learning already-learned regions, and the data in the already learned regions is written in unlearned region. The controlling of the engine is performed on the basis of the data written in the learning map.

Abstract: A method of controlling an operation of an internal combustion engine. A memory has stored therein a plurality of basic values of a control amount by which the operation of the engine is to be controlled, and which conform to at least one operating parameter of the engine, as well as at least one correction value for correcting the basic values. When each of first and second conditions is detected under which the operation of the engine is required to be controlled by respective different amounts, ones of the basic values are read from the memory, which corresponds to the value of the at least one operating parameter. When a predetermined one of the first and second conditions is detected, the at least one correction value is read from the memory, by which the read basic values are corrected by the read correction value. The operation of the engine is controlled by control amounts based upon the corrected basic values.

Abstract: A fuel supply control system for an internal combustion engine comprises a start detecting device for detecting a starting condition of the engine, and a starting fuel supply device for supplying an amount of fuel required for starting the engine which corresponds to an output generated from a device for detecting an engine temperature, when the start detecting device detects the starting condition of the engine. A timer is associated with the start detecting device for counting time elapsed from the time the start detecting device detects the starting condition of the engine and generating an output corresponding to the elapsed time. A fuel decreasing device is responsive to respective outputs from a throttle opening sensor and the timer, for decreasing the amount of fuel for starting the engine, supplied by the starting fuel supply device.

Abstract: When auxiliary equipment of a car, such as car air conditioner, is required to operate, fuel to be supplied for an engine is at first increased and at a predetermined time thereafter additional air commensurate with the increment of fuel is supplied, and after the engine increases its output power by the above mentioned increase of fuel and air, the auxiliary equipment is actually operated, whereby the number of revolutions of the engine is prevented from decreasing.

Abstract: An engine control apparatus comprises a plurality of sensors for detecting the operation state of an engine, means for calculating, on the basis of signals produced from the sensors, a correction amount which corrects a predetermined controllable quantity, means for calculating a learned correction amount by averaging values of the correction amount by a reference occurrence frequency, means for calculating, under a predetermined condition, the learned correction amount by averaging values of the correction amount by an occurrence frequency which is smaller than the reference occurrence frequency, and means for correcting the controllable quantity in accordance with the correction amount and the learned correction amount.

Abstract: A novel method of controlling air-fuel ratio for an internal combustion engine is disclosed, which comprises a memory area for holding regional compensation factors used for air-fuel ratio control, a memory area for holding new regional compensation factors obtained by learning, and a memory area for holding regional compensation factors based on the result of the learning immediately before the latest learning, thus rationalizing the new setting and updating proceses of regional compensation factors according to the result of learning.

Abstract: A system for correction of the fuel injection time control upon variation in altitude, for a heat engine having an electronic fuel injection system, and having means for substantially detecting the value of the external atmospheric pressure and the consequently correcting the value of induction air pressure utilized by a central processing unit of the injection system for calculating the injection time.

Abstract: In a two stroke fuel injection type internal combustion engine provided with intake and exhaust valves, a basic amount of fuel to be injected is calculated in accordance with an engine load and engine speed. Values of a factor corresponding to a ratio of air captured by an engine cylinder for combustion to the total amount of air introduced into the engine are stored in a memory in accordance with combinations of an engine load and engine speed. A value of a captured air factor corresponding to a detected combination of an engine load and speed is calculated by a map interpolation. The basic amount is corrected by the captured air factor so that a desired air-fuel ratio is obtained. The captured air factor may be further corrected in accordance with a secondary engine condition, other than an engine load and speed, such as a cooling water temperature, intake air temperature, atmospheric air temperature, atmospheric air pressure, exhaust gas temperature, or intake pressure.

Abstract: An apparatus for controlling the timing of fuel injection into a diesel engine, including means for computing a target time at which injection should occur and means for sensing when injection actually occurs, with respect to a reference crankshaft position, feedback control means for adjusting the actual injection time to bring this into coincidence with the target injection time, means for sensing when firing of fuel within an engine cylinder actually occurs and for computing a target firing time based on the current operating status of the engine. A compensation factor is computed based on the difference between the actual and target firing times, and is utilized to modify the actual fuel injection time such as to bring the actual and target firing times into coincidence.

Abstract: A fuel injection control system for an engine having a plurality of cylinders includes a plurality of driver units for actuating fuel injection valves on the respective cylinders, a processing unit for starting processing operation in synchronism with a cycle of operation of the cylinders when the engine is in a normal operation mode, to compute times for which the fuel injection valves are to be opened based on an engine operating condition in the normal operation mode and to issue processed data, and for starting processing operation out of synchronism with the cycle of operation when the engine is in a particular operation mode, to compute times for which the fuel injection valves are to be opened based on an engine operating condition in the particular operation mode and to issue processed data, and a plurality of counters for successively opening the fuel injection valves through the driver units based on the processed data set in the counters and corresponding to the computed times from the processing m

Abstract: A system for controlling the operation of an internal combustion engine on the basis of air/fuel ratios and engine loads. A flow rate of intake air sucked into the engine and the cycle of engine revolutions are detected to determine an average flow rate of intake air, which is then used in cooperation with a compression ratio and an engine displacement to determine a net flow rate of intake air or the charging efficiency of the engine. This parameter represents a precise engine load and is used to regulate fuel injected into the engine. As a result, engine operations may be optimally controlled even during transitional operating states of the engine.

Abstract: A rotation signal Ne is generated for every 1.degree. of rotation of the engine crankshaft together with a crankshaft angle signal G for every 360.degree. of crankshaft rotation. In response to each rotation signal Ne, a pseudo random number generator generates random number data which is converted to analog data by a D/A converter and supplied to a comparator circuit. An intake air pressure detection data Pim is also supplied to the comparator circuit and the two signals are compared. When the detection data Pim is larger than the converted analog data, the comparator output level is high. The output from the comparator is read for every rotation signal Ne and, when the detection data is larger than the analog data from the D/A converter, a counter is incremented. The count value is read for every generation of the crankshaft signal G and is supplied to the engine control unit as the intake air pressure detection data. The counter is then reset to the initial count value.

Abstract: A method of controlling the quantity of fuel to be injected into an intake manifold for an engine by a fuel injection unit comprising the steps of identifying parameters indicative of a change in the dynamic characteristic of the fuel supply system due to changes in the environmental conditions including the atmospheric pressure and engine temperature, estimating the quantity of fuel to be supplied to the engine cylinder on the basis of the identified parameters, and controlling the quantity of fuel to be injected so that the ratio between the measured quantity of air supplied to the engine cylinder and the estimated quantity of fuel supplied to the engine cylinder attains the desired air-fuel ratio.