Abstract: A device for detecting the misfire in an internal combustion engine which features improved reliability for judging the misfire in all operation regions by using either the revolution data or the ionic current depending upon the operation region.

Abstract: In a misfire detecting device for an internal combustion engine having a plurality of cylinders, revolution detecting device detects the revolution of an engine; arithmetic device calculates deflections in revolution of the engine for each of the cylinders on the basis of a period of revolution of the engine in correspondence to the order of combustion of the cylinders; threshold value determining device determines a misfire decision threshold value for the cylinders from a value obtained by smoothing arithmetic values which are determined for the cylinders by the arithmetic device, and a predetermined value; and misfire deciding device compares the arithmetic values provided by the arithmetic device with the threshold value to comparison, to determine the occurrence of a misfire in any one of the cylinders.

Abstract: A microcomputer-based misfire detecting apparatus for a multi-cylinder internal combustion engine. A crank angle sensor is coupled to the engine for detecting first and second predetermined angular intervals set before and after a predetermined reference crank position close to a TDC preceding to combustion stroke in each of the cylinders. An acceleration detector is connected to the output of the crank angle sensor for determining an acceleration based on a time ratio between times taken for a crank shaft to rotate through the first and second predetermined angular intervals, respectively, from the output signal of the crank angle sensor. A misfire occurrence detector is connected to the acceleration detector for detecting misfire occurring in the engine cylinder on the basis of the output signal of the acceleration detector.

Abstract: A misfire detecting device is provided with a rotation detecting sensor 3 for detecting rotation signals corresponding to the timing of ignition of the cylinders of an engine. The device further includes a control unit which has continuous misfire detecting means for detecting the occurrence of a continuous misfire in the engine and intermittent misfire detecting means for detecting the occurrence of an intermittent misfire in it. Those detecting means operate according to the rotation signals provided by the rotation detecting sensor. When either the continuous misfire detecting means or the intermittent misfire detecting means detects the occurrence of a misfire, it is determined that a misfire has actually occurred in the engine.

Abstract: An apparatus for controlling air supply to an internal combustion engine comprises a main intake pipe for supplying air to the engine, a throttle valve disposed in the main intake pipe for controlling flow rate of the air supplied to the engine in dependence on depression of an accelerator pedal, a plurality of bypass passages disposed in parallel with the main intake pipe for allowing the air to be supplied to the engine by bypassing the throttle valve, a plurality of bypass valves installed in the plurality of bypass passages, respectively, a diagnosis means for diagnosing the throttle valve and devices associated therewith as to occurrence of abnormality, and a controller responsive to detection of the abnormality to close the throttle valve while allowing the bypass valves to control the intake air flow in dependence on depression of the accelerator pedal. The controller responds to detection of the abnormality for shifting a range of engine operation from a normal operation range.

Abstract: A control apparatus with a fail-safe function not only serves to enhance acceleration performance of a motor vehicle but also prevents a runaway upon occurrence of a failure in a throttle control system. An accelerator pedal actuation detector detects a magnitude of depression of an accelerator pedal by the driver. A vehicle speed detector detects a running speed of the vehicle. A gear ratio detector detects a gear ratio or gear position of a transmission. A plurality of target throttle opening patterns representing relations between target values of throttle opening degree and depression magnitudes of the accelerator pedal are stored in a memory. A first controller selectively determines an optimum target throttle opening pattern on the basis of the vehicle speed and the gear ratio to thereby control a throttle actuator for actuating a throttle in accordance with the selected pattern. An intake air quantity detector detects a quantity of intake air fed to an engine of the motor vehicle.

Abstract: A signal processing apparatus enjoying a remarkably enhanced operation speed while ensuring accurate control capability due to data holding and learning control includes an A/D converter for converting an analog signal into a digital signal, a packet interface for generating a packet on the basis of the digital signal, a timing port controller for controlling the timing of operation of the A/D converter and generating output data on the basis of the packet, a power supply interruption detecting circuit for detecting a decrease in source voltage to thereby generate a power supply interruption detecting signal, and a data flow processor including a data store and a data flow loop for processing the packet in accordance with tag information contained in the packet. The data flow processor responds to the power supply interruption detecting signal to save electric power from consumption and hold the content of the data store.

Abstract: An output current of an alternator and a load current are detected by current sensors 5 and 6. When the output current of the alternator has a predetermined value or lower, generation of electricity by the alternator is stopped. When the load current has a predetermined value or higher, generation of electricity is resumed. When the load current is increased, a load-responsive control for the alternator and an intake air increasing control is performed, and the generation of electricity of the alternator is stopped at an acceleration time of the engine, and the output of the alternator is gradually increased.

Abstract: An electronic control device for an internal combustion engine having a control unit for detecting a running state of an engine, and which controls a fuel quantity or an ignition timing of the engine in accordance with the running state, where the electronic control device monitors the transient running state of the engine, and includes a fuel property sensor for detecting a fuel property, such that the fuel quantity or the ignition timing is corrected in accordance with the fuel property under the transient running state.

Abstract: An intake air flow control system for an internal combustion engine of a motor vehicle comprises an accelerator pedal depression sensor for detecting depression depth of an accelerator pedal, a throttle actuator for regulating opening degree of a throttle valve in dependence on the depression depth of the accelerator pedal, a bypass intake passage which bypasses an intake pipe at a location where the throttle valve is disposed, a bypass control valve installed in the bypass intake passage, an abnormality detector for detecting abnormality of control of the throttle actuator, and a controller for controlling the opening degree of the bypass control valve in dependence on depression depth of the accelerator pedal in response to detection of abnormality of in the control performed through the throttle actuator. Operation of the engine can be fail-safed even upon occurrence of failure in the throttle control system in the fully closed state of the throttle valve.

Abstract: A method of processing signal for a thermal type flow sensor having a temperature dependence resistance employing platinum and the like and a holding member made of alumina for holding it so as to compensate for response delay when fluid flow is changed, in which, when the fluid flow is maintained in a stationary state, the so-called equilibrium state, by steps of setting in advance the relation between a flow related value which changes according to flow change and a first operational value showing the temperature characteristic of the holding member which changes according to flow so as to make the flow related value as a parameter, calculating the first operational value from the flow related value when flow is detected in accordance with the predetermined relation, comparing the calculated first operational value with the second operational value which is set in relation with the first operational value, correcting the second operational value so that it approximates the first operational value according

Abstract: A cruise control apparatus for a vehicle is effective to prevent hunting in the vehicle speed and resultant shocks which are apt to occur when the vehicle is travelling on a down slope under cruise control. A cruise control unit is adapted to be actuated by a driver of the vehicle for automatically controlling the opening degree of a throttle valve so that the speed of the vehicle is maintained at a predetermined target speed. A fuel control unit controls the fuel supply to the vehicle engine such that the fuel supply is cut off when the throttle valve is moved to a fully closed or idling position thereof with the number of revolutions per minute of the engine being equal to or greater than a predetermined value during cruise control. In one aspect, the fuel cut-off is cancelled when the speed of the vehicle decreases below a predetermined lower limit for the target speed during cruise control, and at the same time, the cruise control is temporarily interrupted for a predetermined length of time.

Abstract: A misfire detection device for an internal combustion engine determines the time length tx from each ignition timing, as determined by the ignition signal Se, to a predetermined angle of the crank shaft after the ignition timing as determined by the crank angle pulse signal Sd. When the difference between the current and the preceding time lengths thus determined exceeds a reference level, an occurrence of misfire is detected. Alternatively, when the difference .DELTA..omega.d between the instantaneous angular velocities immediately after the ignition timing and a predetermined angle thereafter as determined on the basis of the crank angle pulse signal Sd is less than a predetermined reference level, an occurrence of misfire is detected.

Abstract: An input processing circuit for an air flow sensor comprising a differential amplifier connected through two lines to an air flow sensor and having an operational amplifier an output signal from the air flow sensor and sends a result of this processing to an analogue value - digital value conversion integrated circuit. An output signal from the air flow sensor is supplied to the differential amplifier through a filter circuit so as to prevent an occurrence of error in measuring the amount of sucked air for an internal combustion engine due to various noises. A connection of an inverting input terminal end of the differential amplifier to a ground through a resistor prevents an error caused by a breakage of a reference voltage line connected between the air flow sensor and the input processing circuit. A differential input amplifier circuit also prevents an error caused by a variation in potential resulting from consumption current of an air flow sensor or the like from being generated.

Abstract: A method of processing a signal of a thermal flow-rate sensor, provides a temperature monitor for monitoring a temperature at a representative point on a substrate support member; obtains the temperature at the representative point corresponding to the flow rate by use of the temperature monitor; and corrects an output of the sensor in accordance with a value corresponding to the temperature as well as a value corresponding to the temperature at the representative point when the flow rate is in a steady state.

Abstract: A control apparatus for a suction air quantity of an engine adapted to detect a revolution number of the engine, to measure a difference between the detected revolution number of the engine and a target revolution number of the engine, and to regulate a suction air quantity in a bypass passage which bypasses a throttle valve of the engine corresponding with the difference so that the revolution number of the engine agrees with the target revolution number of the engine, which comprises misfire detecting means for detecting a misfire of the engine, means for outputting a first signal of correcting a timewise change of a suction quantity of the engine based on the difference between the revolution number and the target revolution number of the engine, means for retaining the first signal to a value just before the misfire in case of detecting of the misfire, and means for outputting a second signal for increasing the suction quantity so that the suction quantity is increased in case of detecting of the misfire.

Abstract: A revolution speed control apparatus for an internal combustion engine comprises an intake air quantity setting device for setting an intake air quantity to an internal combustion engine, a target revolution speed setting device for setting a target revolution speed for the engine, a revolution speed detector for detecting the revolution speed of the engine, and idling state detector for detecting an idling state of the engine, a revolution speed feedback-control quantity calculating device for calculating a revolution speed feedback control quantity in accordance with an error between the target revolution speed and an actual revolution speed of the engine when the engine is in an idling state, a hot wire type air flow sensor for detecting an intake air quantity to the engine, a correction value memory to transfer with time the revolution speed feedback control quantity in accordance with an error between an actual intake air quantity and a target intake air quantity which is obtained from the intake air qua

Abstract: An engine control apparatus is provided with a control unit in which a fuel supply quantity Q.sub.f or a ignition timing .theta..sub.i is corrected to maximize an evaluation parameter A=P.sub.i /(Q.sub.a /N) obtained on the basis of a suction air quantity Q.sub.a, an engine speed N and a mean effective pressure P.sub.i in a engine, or to maximize a parameter B=P.sub.i /P.sub.b obtained on the basis of a suction pipe pressure P.sub.b and the mean effective pressure P.sub.i, or to maximize a maximum pressure P.sub.max or a mean effective pressure P.sub.i for every combustion cycle, so that control is performed on the basis of the result of the above correction. The control unit also performs feedback control of the fuel supply quantity Q.sub.f and corrects the ignition timing. Further, the control unit performs feedback control in a predetermined load-operation range of the engine, and stops the feedback control and corrects the fuel supply quantity Q.sub.

Abstract: An engine control apparatus is provided with a control unit in which a fuel supply quantity Q.sub.f or a ignition timing .theta..sub.i is corrected to maximize an evaluation parameter A=P.sub.i /(Q.sub.a /N) obtained on the basis of a suction air quantity Q.sub.a, an engine speed N and a mean effective pressure P.sub.i in a engine, or to maximize a parameter B=P.sub.i /P.sub.b obtained on the basis of a suction pipe pressure P.sub.b and the mean effective pressure P.sub.i, or to maximize a maximum pressure P.sub.max or a mean effective pressure P.sub.i for every combustion cycle, so that control is performed on the basis of the result of the above correction. The control unit also performs the feedback control of the fuel supply quantity Q.sub.f and corrects the ignition timing by the above-mentioned correction means. Further, the control unit performs feedback control in a predetermined load-operation range of the engine, and stops the feedback control and corrects the fuel supply quantity Q.sub.

Abstract: The invention relates to a novel fuel controller of an internal combustion engine. In particular, it relates to a novel fuel controller which securely corrects characteristic variation with time of air-flow sensor used for controlling flow of fuel. The fuel controller embodied by the invention incorporates a memory which stores the negative feedback correction value of air-fuel ratio or the value related to it at the flow-volume point representing variation of characteristic of air-flow sensor or at an adjacent point of it so that the basic volume needed for controlling flow of fuel can be corrected by applying the content of memory. As a result, even if characteristic of the air-flow sensor varies, the system can achieve satisfactory control condition. The fuel controller inhibits renewal of the study on the negative feedback correction value for the predetermined period in accordance with the opening/closing condition of the purge-control valve.