Abstract: In a flow rate measuring apparatus having a Karman vortex sensor for generating a signal in response to a flow rate of a fluid, the flow rate of the fluid is calculated in accordance with the period of the signal of the Karman vortex sensor, and is also corrected in accordance with this period.

Abstract: In a flow rate measuring apparatus having a Karman vortex sensor for generating a signal in response to a flow rate of a fluid, the flow rate of the fluid is calculated in accordance with the period of the signal of the Karman vortex sensor, and is also corrected in accordance with this period.

Abstract: A fuel injection control device for an internal combustion engine in which a fundamental fuel injection amount is set according to suction air amount per one revolution of the engine Q/N. The fuel injection control device includes a transitional operation start timing detector for detecting an acceleration start timing or a deceleration start timing, an engine rotational number measurer for measuring a predetermined number of rotations of the engine from the acceleration start timing or the deceleration start timing, a throttle valve angle detector for detecting that a throttle valve angle is out of a set range, and apparatus for setting an upper limit value and/or a lower limit value of Q/N when the throttle valve angle detector generates a signal showing that the throttle valve angle is out of the set range until the engine rotational number measurer measures the predetermined number of rotations of the engine.

Abstract: A crank angle sensor generates a reference position signal and a crank angle signal as an internal combustion engine rotates. A counter counts the crank angle signals and, when its count value has reached a first set value, it goes to a second set value. Where the count value of the counter changed from the first to the second set value before the generation of the reference position signal, a control circuit sets the counter to the second set value when the reference position signal is generated. Where the count value of the counter did not change from the first to the second set value before the generation of the reference position signal, the control circuit sets the counter to the second set value when the counter is at the first set value and the reference position signal is produced.

Abstract: In a control method and device for a digitally controlled internal combustion engine, engine condition signals are read out from sensors for detecting conditions of the engine, with selected sensor outputs read out in synchronism with rotation of the engine at a predetermined crank angle empirically corresponding to a low engine load and resulting high battery voltage, the predetermined crank angle being within at least 20 crank angle degrees of bottom dead center.

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: Fuel supply to an internal combustion engine is controlled in accordance with the operating condition of the engine. Enrichment operation after the starting of the engine is executed for a period of from the start of the engine until the actual engine temperature becomes higher than the engine temperature at the start thereof by a predetermined value.

Abstract: An electronic engine control apparatus and method for computing various engine operating parameters such as fuel injection amount on the basis of input signals from a temperature sensor which detects engine temperature, wherein the signals from the temperature sensor are read more frequently before the complete explosion (i.e., running without a starter motor) of the engine than after attainment of complete explosion (i.e., after a start period) so that degradation of accuracy in the computed fuel injection amount, due to variation of the input signals from the temperature sensor which is caused by the starting motor, is reduced.

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: A fuel injection quantity is varied by correcting a correction value so that a mean value of a factor of air-fuel ratio feedback correction obtained from the output of an O.sub.2 sensor takes a value within a predetermined range centered at a value corresponding to a stoichiometric air-fuel ratio, and a fuel injection quantity is calculated based on a basic fuel injection quantity, the factor of air-fuel ratio feedback correction and the correction value, thereby to effect control so that the air-fuel ratio converges in proximity of the stoichiometric air-fuel ratio.

Abstract: An engine wherein a basic fuel injection flow rate from an injector is obtained based on an intake manifold pressure and an engine rotational speed. A change with time of the opening degree of a throttle valve and a change with time of the intake manifold pressure are calculated, and the basic fuel injection flow rate is corrected commensurate with the values of the changes described above to cause the basic fuel injection flow rate to be an ideal air-fuel ratio. When the change with time in opening degree of the throttle valve or the change with time of the intake manifold pressure is smaller than the respective predetermined values, the basic fuel injection flow rate is corrected, and, after the correction, if the values of changes thereof become smaller than the respective predetermined values, the basic fuel injection flow rate thus corrected is caused to approach the injection flow rate before the correction.

Abstract: Electronic fuel injecting method and device for an internal combustion engine, wherein a basic injection time is obtained in accordance with an intake pressure of the engine and an engine rotational speed. During transitions, the basic injection time is corrected in accordance with the operating conditions of the engine so as to determine a fuel injection time. A throttle valve opening correction is increased or decreased in accordance with a changing speed of the throttle valve opening, and subsequently, is attenuated at a predetermined attenuation rate or restored at a predetermined restoration rate. An intake pressure is increased or decreased in accordance with a changing speed of the intake pressure, and subsequently, is attenuated at a predetermined attenuation rate or restored at a predetermined restoration rate. These corrections are combined to obtain a correction value for acceleration and deceleration, and the correction value is used to modify the basic injection time.

Abstract: Fuel supply to an internal combustion engine is controlled in accordance with a fuel injection signal which depends on intake manifold pneumatic pressure and on engine running speed. A basic pulse width of the fuel injection signal is calculated by (1) multiplying a one-dimensional function of the detected intake manifold pneumatic pressure by a first weighting factor, (2) multiplying a two-dimensional function of the detected intake manifold pneumatic pressure and of the detected engine running speed, and (3) totalling the multiplied functions.

Abstract: In an electronic fuel injecting method and device for an internal combustion engine, wherein a basic injection time is obtained in accordance with an intake pressure of the engine and an engine rotational speed, and, during transition, the basic injection time is corrected in accordance with the operating conditions of the engine so as to determine a fuel injection time, out of three factors including an after-idle increase correction in which a correction value is increased to a predetermined level when an idle switch is turned "OFF", a throttle valve opening increase or decrease correction in which a correction value is obtained in accordance with a changing speed in opening of a throttle valve, and an intake pressure increase or decrease correction in which a correction value is obtained in accordance with a changing speed of the intake pressure, at least two factors are combined to obtain an increase correction value for acceleration or a decrease correction value for deceleration, and, when the factors a

Abstract: An electronic fuel injecting method and device for an internal combustion engine, wherein a correction in accordance with the operating conditions or the like of the engine is effected on a basic injection time obtained in accordance with an intake pressure or an intake air flowrate, and a rotational speed of the engine, to thereby provide fuel in synchronism with the rotation of the engine. When the operating conditions of the engine reach a predetermined condition, fuel is provided at a predetermined injection time not in synchronism with the rotation of the engine. When requirements for non-synchronous injection take place during synchronous injection, the time period for the synchronous injection is prolonged by the appropriate non-synchronous injection time. When more than one non-synchronous injection requirement occurs during a single synchronous injection, the synchronous injection time is lengthened by a time corresponding to only one of the non-synchronous injection requirements.

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 an electronic fuel injecting method and device for an internal combustion engine, wherein a basic injection time is obtained in accordance with an intake pressure of the engine and an engine rotational speed, and, during transition, the basic injection time is corrected in accordance with the operating conditions of the engine so as to determine a fuel injection time, when a change in value of the intake pressure in every first predetermined time period exceeds a first criterion value, an increase correction for acceleration or a decrease correction for deceleration is effected, in case the change in value of the intake pressure in every first predetermined time period does not exceed the first criterion value, if a change in value of the intake pressure in every second predetermined time period being longer than the first predetermined time period exceeds a second criterion value, at least an increase correction for acceleration is effected, and if the change in value of the intake pressure does not excee

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: A feedback type air fuel ratio controlling system for detecting and controlling an exhaust gas composition of an engine. A gas sensor provides a sensor signal related to an exhaust gas concentration. This sensor signal is coupled through an automatic gain control (AGC) DC level amplifier to a deviation detector. The deviation detector compares the signal to a reference signal V.sub.p representing a stoichiometric air fuel mixture and provides a correction signal for adjusting the engine's air fuel ratio. The AGC DC level amplifier provides automatic DC level compensation for a slowly deteriorating sensor and, working in combination with the deviation detector, an AC hysteresis response for judging rich to lean and lean to rich changes sensed by the exhaust gas sensor.

Abstract: Disclosed is an apparatus for controlling an electric motor for driving a cooling fan of an internal combustion engine. The apparatus comprises an engine operation detecting means, a timer, an engine temperature detecting means, a logical product generating means, and a motor controlling means. The electric motor is driven only when all of the following three conditions are satisfied: the engine is not operating; a predetermined timing period initiated when the engine stops operating has not expired; and a temperature in the engine room is higher than a predetermined value.