Abstract: A lubricating apparatus for an internal-combustion engine comprises a detector for detecting whether the engine runs or not, a heat storage reservoir connected to lubricating oil outflow and inflow ports of the engine by a circular pipe system for storing the oil and maintaining its temperature, the heat storage reservoir being provided outside the engine, a hydraulic pump provided between the inflow port and the heat storage reservoir for controlling the supply of the oil stored in the heat storage reservoir to portions of the engine in response to a control signal, and a controller responsive to an output of the detector for producing the control signal to stop the hydraulic pump in order to maintain a temperature of the oil stored in the heat storage reservoir when the detector detects a stop of the engine and for producing the control signal to actuate the hydraulic pump to supply the oil, whose temperature is maintained by the heat storage reservoir, to the portions of the engine.

Abstract: A system for correcting for atmospheric pressure without using an atmospheric pressure sensor. A single pressure sensor measures air pressure in the intake manifold of a fuel injected engine. A control unit controls the fuel amount and injection timing in accordance with various engine parameters. The intake pressure at a predetermined time is estimated as being indicative of atmospheric pressure. This intake pressure may be further corrected to provide a better estimate. When the engine operates at a low speed and high load, this pressure data is also indicative of atmospheric pressure. The amount of fuel to be injected and the ignition timing can be controlled using this updated atmospheric data. This provides better operation of the system.

Abstract: A system for controlling the operating condition of an engine in which a temperature sensing element constitutes an airflow measuring device disposed in an intake air passage of the engine. The temperature sensing element is supplied with a heating current in response to a start pulse signal produced with every one-half period of each combustion cycle of the engine. A comparator delivers an output signal when a reference temperature set on the basis of the air temperature measured by an auxiliary temperature sensing element is reached by the temperature of the temperature sensing element. A pulse signal indicative of the time interval between the generation of the start pulse signal and a rise in the output signal of the comparator is delivered as an airflow measurement signal.

Abstract: An engine control apparatus for controlling the quantity of fuel injected into the engine is equipped with an intake air flow rate measuring device for detecting the operating state of the engine. This measuring device has a heat sensitive element, which is located in the intake pipe, and outputs a pulse signal having a pulse width T corresponding to the intake fuel amount. Engine control apparatus has a plurality of map memory means in which a plurality of functions f.sub.1 (N), f.sub.2 (N), f.sub.3 (N), which express the polynomial approximation ##EQU1## for expressing the air flow rate G/N per engine revolution, are stored as the parameters of the number of engine rotations N. These functions are read out from the maps and, based on the number of engine rotations N, the fuel injection amount corresponding to the pulse width T of the air flow rate is calculated.

Abstract: An air/fuel ratio control system for an internal combustion engine that compensates, the amount of fuel supplied at engine starting based on lapsed time since the engine was operated and stopped. A lapse time from the immediately previous engine stop to the subsequent engine start is determined. Based on this lapse time, an increase value of fuel to be supplied into the engine's intake air by fuel injection valves is determined. This increase value is determined according to a pre-established of fuel temperature. The fuel supply amount is corrected upon engine start on the basis of the increase value.

Abstract: A control system for an engine has a temperature sensitive element as part of a device for measuring the air flow in an air intake manifold to the engine. Further, a first pulse signal is generated, corresponding to the rotation of the engine, for controlling the setting of a flip-flop. A transistor is conducted in the set state of the flip-flop to supply a heating electric current to the element. The element supplied with the current is raised to the temperature that corresponds to the air flow in the manifold. When the temperature of the element is raised until the specified temperature difference to the air temperature (measured by a sub temperature sensitive element) is set, the temperature difference is detected by a comparator, and the flip-flop is reset by the detection signal.

Abstract: An engine control apparatus has an air flow rate measuring device for measuring an intake air flow rate. A temperature sensing element having a temperature characteristic and constituting the device is arranged in an intake pipe. The device generates an output pulse signal having a pulse width T corresponding to the intake air flow rate. An engine control unit has the one-dimensional map for storing the relationship between the engine speed N and the pulse width to of the signal corresponding to the air flow rate. This data to is read out from the one-dimensional map in accordance with the engine speed N. Subsequently, the data to is subtracted from the data T to calculate a time duration t. The unit also has a two-dimensional map for storing the relationship between each time duration t and the corresponding rate G/N in correspondence with each of the present engine speeds. A corresponding rate G/N is read out from the two-dimensional map in response to the calculated time duration t.

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: A method of controlling an internal combustion engine in which the pressure in a cylinder or working chamber of the engine is detected by reading the output signal which is delivered from a pressure sensor when a predetermined time has elapsed from a point of time when the pressure should be detected. Based on this pressure detection, the fuel supply amount or ignition spark timing is controlled.

Abstract: A gas sensor of constant-current type is used to detect a gas component in exhaust gases from an internal combustion engine so as to perform feedback control of air/fuel ratio of an air-fuel mixture supplied to the engine. In order to detect an air/fuel ratio which is richer than a stoichiometric value, a voltage applied to the gas sensor is set to a high value so that the gas sensor does not exhibit a constant-current characteristic. In the case it is desired to detect an air/fuel ratio which is either richer or leaner than the stoichiometric value, the voltage may be changed between the high value and a lower value at which the gas sensor exhibits a constant-current characteristic. Engine parameters are detected to determine whether the engine requires a rich mixture or a lean mixture, and the voltage may be changed as the result of such determination.

Abstract: An air-fuel ratio control system applicable to engines having exhaust gas recirculation (EGR). A basic amount of fuel to be injected is determined on the basis of an intake air pressure or a throttle opening. When the operating condition of an engine meets a predetermined condition for an exhaust gas recirculation control mode, a correction coefficient for the exhaust gas recirculation control mode is read from map data stored in memory means to correct the basic amount therewith. Immediately after the correction coefficient has been changed, the basic amount is corrected with a correction coefficient related to the values of the correction coefficient immediately before and after it is changed.

Abstract: Fuel injection modes including an independent injection mode, group injection mode and simultaneous injection mode are changed over in accordance with an engine operating condition, for example, a load condition. The independent injection mode is selected when the engine is operating in a low load condition, and the fuel injection timing for each cylinder is controlled independently. When the low load condition of the engine changes to an intermediate load condition, the group injection mode is selected and the fuel injection timing is controlled for each group of cylinders formed by grouping the cylinders into at least two groups. The simultaneous injection mode is selected when the intermediate load condition changes to a high load condition, and the fuel injection timing for all the cylinders is controlled to be simultaneous.

Abstract: An ignition timing control method and an apparatus for internal combustion engines in which the ignition timing of the engine is calculated from a base value obtained by detecting a first operation state of the engine and from a learned correction value obtained in accordance with the record content of a nonvolatile memory, the ignition timing being corrected by rewriting the nonvolatile memory in accordance with the detection result of second and third driving states of the engine, as desired.

Abstract: For controlling an internal combustion engine at least first and second control maps are provided in which first and second control variables are stored respectively, which are addressible in response to different combinations of output parameters of the engine. First and second weighting factors are derived for weighting first and second control variables which are derived respectively in response to a first and a second combination of engine output operating parameters. The weighted first and second control variables are summed to derive a combined control variable for controlling one of the input operating parameters.

Abstract: Supercharging pressure produced by a supercharger driven by the exhaust gasses is detected so that frequency of combustion in an internal combustion engine is reduced to lower the engine output power. In order to reduce the frequency of combustion, the number of times of fuel injection may be thinned out or fuel injection into one or some of the cylinders of the engine may be stopped for a given period of time. Alternatively, the frequency of ignition may be reduced or ignition in one or some of the cylinders may be stopped for a given period of time. The control of fuel injection and the control of ignition may be combined. A microcomputer may be used to perform the method according to the present invention where the microprocessor thereof is arranged to execute a main routine and an interrupt service routine. In the main routine, data related to the supercharging pressure is stored in a memory, and the interrupt service routine, fuel injection and/or ignition is performed.

Abstract: The idle speed of an internal combustion engine is controlled in response to a variable ignition timing control signal from a microcomputer. The microcomputer derives this control signal as a function of the magnitude of engine speed variation which occurs during engine idle periods to cause the ignition timing to vary quickly in response to a transitory engine load variation. An auxiliary air delivery system may be advantageously incorporated in the idle speed control system to cooperate with the ignition timing control in response to the engine speed variation.

Abstract: An engine speed control method and apparatus employs at least two basic control variable maps comprising a first basic control variable map for determining the desired air flow to an internal combustion engine in accordance with the warming conditions of the engine during the starting period and a second basic control variable map for determining the desired air flow in accordance with the warming conditions of the engine after the starting period, and the maps are used selectively in accordance with the warming conditions of the engine. Upon change-over from the control according to one map to the control according to the other map, the air flow is varied gradually at intervals of predetermined engine revolutions or a predetermined period of time so as to effect the change-over to the control according to the desired map.

Abstract: Spark ignition timing of an internal combustion engine is oscillated on each side of a variable reference setting by varying it at stepwisely variable amounts during positive and negative swings and the resultant engine speed is detected in at least three successive phases. The detected engine speed values are compared one against each other to determine whether they satisfy one of two specified conditions. The variable reference is adjusted in a direction toward an optimum position depending on which one of the conditions is satisfied.

Abstract: A gas flow measuring apparatus is provided with an air flow sensor mounted in a suction duct upstream from a throttle valve and exposed to the air flow through the suction duct. The air flow sensor includes a ceramic flat plate mounted in the suction duct so that the main surfaces of the ceramic flat plate are parallel with the air flow. First and second temperature-dependent resistor coatings are formed on the main surfaces of the ceramic flat plate so that the first resistor coating and the second resistor coating are respectively formed on the downstream and upstream end portions of the ceramic flat plate by printing or evaporating a platinum. An electric heater coating is formed between the first and second resistor coatings but spaced therefrom to affect only the first resistor coating, and the heater coating is also formed by printing or evaporating a platinum.

Abstract: To control the idling speed of an automotive engine, a control amount is predetermined which determines an idle air flow for providing a basic idling speed and the idle air flow is adjusted in accordance with the control amount. Also, when the engine is idling after the completion of the warm-up operation, in accordance with the difference between a predetermined desired engine idling speed and the actual engine speed attained after the adjustment of the idle air flow in accordance with a basic control amount, a correction value for compensating the basic control amount is computed and memorized such that the actual engine idling speed is adjusted to the desired speed, whereby the idle air flow is adjusted in accordance with the memorized correction value and the basic control amount in all the engine operating conditions including the idling operation.