Abstract: An air-fuel ratio control system for an engine in which a fuel injection amount is calculated according to the engine operating conditions and is corrected according to the output of an air-fuel ratio sensor, comprises a base fuel injection amount calculating section for calculating a base fuel injection amount corresponding to the stoichiometric air-fuel ratio on the basis of the intake air amount, a target air-fuel ratio calculating section for calculating a target air-fuel ratio according to the engine operating condition, a reference value calculating section for calculating a reference value which represents the target air-fuel ratio and is submitted to comparison with the output of the air-fuel ratio sensor, a feedback correction coefficient calculating section for calculating a feedback coefficient according to the deviation of the output of the air-fuel ratio sensor from the reference value, and a final fuel injection amount calculating section which corrects the base fuel-injection amount on the basi

Abstract: An automotive driving control system comprises a stepless transmission provided between the engine and the driving wheels, a transmission controller for controlling the transmission ratio of the stepless transmission, a throttle valve driver for driving the throttle valve of the engine, and a controller for controlling the transmission controller and the throttle valve driver. The controller controls the transmission controller and the throttle valve driver according to the amount of depression of the accelerator pedal.

Abstract: An automotive driving control system comprises a stepless transmission provided between the engine and the driving wheels, a transmission control for controlling the transmission ratio of the stepless transmission, a throttle valve driver for driving the throttle valve of the engine, an accelerator position sensor for detecting the amount of depression of the accelerator pedal, and a control for controlling the transmission control and the throttle valve driver. The control controls the transmission control and the throttle valve driver to respectively control the opening degree of the throttle valve and the transmission ratio of the stepless transmission so that engine output corresponding to the amount of depression of the accelerator pedal is obtained. There is further provided an acceleration requirement detector for detecting an acceleration requirement by way of change in the amount of depression of the accelerator pedal, the rate of change of the same (i.e.

Abstract: An automotive driving control system comprises a stepless transmission provided between the engine and the driving wheels, a transmission controller for controlling the transmission ratio of the stepless transmission, a throttle valve driver for driving the throttle valve of the engine, an operating state detector for detecting a particular operating state of the engine such as "knock" or resonance with the vehicle body, and a controller for controlling the transmission controller and the throttle valve driver. The controller controls the transmission controller and the throttle valve driver to respectively control the transmission ratio of the stepless transmission and the opening degree of the throttle valve so as to obtain that engine output which corresponds to the amount of depression of the acceleration pedal.

Abstract: A fuel injection valve is provided upstream of a branch-off part of a branched off intake passage, the downstream ends of the branched off passages being connected to a plurality of cylinders of an engine. The fuel injection timing of the injection valve is controlled by a pulse controller. The pulse controller operates to control the pulse timing basically according to the intake air flow and the crank angle of the crank shaft of the engine, and further corrects the timing according to the air fuel ratio difference between cylinders whose intake strokes are adjacent to each other. The correction rate of the timing may be changed according to the degree of the engine load and/or the engine temperature. By the correction of the timing, the air fuel mixture in rich cylinders is partly inhaled into lean cylinders so that the air fuel ratios of the cylinders may be equalized.

Abstract: The idling speed of an internal combustion engine is controlled by controlling the position of a control valve disposed in the intake system of the engine to control the amount of intake air fed to the engine. A desired idling speed is determined according to the operating condition of the engine and the control valve is moved to a temporary target position which is expected to be suitable to obtain the desired idling speed. Then feedback control is carried out to converge the actual idling speed to the desired idling speed. When the actual idling speed is finally equalized to the desired idling speed, the actual position of the control valve at that moment is detected and memorized to be adopted as the temporary target position for the same operating condition in later control of the idling speed.

Abstract: An engine throttle valve operating device comprising a throttle valve operating foot pedal position detector for detecting the position of the foot pedal and producing a foot pedal position signal corresponding to the position of the foot pedal, a rapid acceleration detector connected with the foot pedal position detection for receiving the foot pedal position signal therefrom and producing a rate signal corresponding to a rate of change per unit time of the position of the foot pedal, a throttle valve actuator for actuating the engine throttle valve, a throttle valve driving signal generating circuit responsive to the foot pedal position signal and the rate signal to produce a first drive signal for operating the actuator in accordance with the foot pedal position signal when the rate of change per unit time of the position of the foot pedal is smaller than a predetermined value and a second drive signal for operating the actuator by a greater extent than under the first drive signal when the rate of change

Abstract: An internal combustion engine is provided with an exhaust gas recirculating passage for communicating the intake passage and the exhaust passage thereof. The recirculating passage is provided with a valve for controlling the amount of recirculated exhaust gas. A fundamental air-fuel ratio control value for regulating the air-fuel ratio of the intake gas to a predetermined value is corrected by an operating condition correction value according to the operating condition of the engine. The operating condition correction value is successively changed to an optimal value by comparing the actually obtained air-fuel ratio with a predetermined value. The operating condition correction value for correcting the fundamental air-fuel ratio control value when the exhaust gas recirculation is carried out is changed independently from the same for correcting the fundamental air-fuel ratio correction value when the exhaust gas recirculation is not carried out.

Abstract: Engine cooling system including a cooling water passage having cooling water jackets formed in the engine and a water pump for circulating cooling water through the water passage. A driving motor is provided for driving the water pump and a control circuit for the motor receives an engine speed signal so that the speed of the water pump is decreased to a predetermined low level when the engine temperature is low so that the engine can be warmed up rapidly while maintaining a cooling water circulation for preventing local overheating of the engine.

Abstract: A knock control device having a knock detecting means and an ignition timing control means is provided with a temperature sensor for detecting the temperature of the exhaust system of an internal combustion engine. If the knock detecting means detects occurrence of knock when the temperature of the exhaust system is lower than a predetermined value, the ignition timing control means retards the ignition timing by a first angle which is most desirable for suppressing the knock, while if the knocking detecting means detects occurrence of knock when the temperature of the exhaust system is not lower than the predetermined value, then the ignition timing control means retards the ignition timing by a second angle which is smaller than the first angle.

Abstract: An internal combustion engine having an exhaust gas recirculation system provided with a recirculation control valve. An abnormality detecting circuit is provided to detect that the control valve is held open beyond a desired position position for more than a certain time due for example to a stick in the valve actuating mechanism so as to increase a charge of intake mixture in an idling operation or shutt-off the exhaust gas recirculation.

Abstract: Engine cooling system including cooling water passages having cooling water jackets formed respectively in the hot temperature portion and the cold temperature portion of the engine and water pumps for circulating cooling water through the water passages. Driving motors are provided for driving the water pumps and a control circuit for the motors receives an engine speed signal so that the water pump for the water passage to the cold temperature portion of the engine is stopped when the engine temperature is low so that the engine can be warmed up rapidly while maintaining a cooling water circulation through the water passage in the hot temperature portion for preventing local overheating of the engine.

Abstract: An automobile air-fuel control system is incorporated with an altitude compensator in order to minimize an excessive enrichment of an air-fuel mixture which would occur when the engine is operated at a high altitude under a high load operating condition. This altitude compensator is constituted by a delay circuitry operable to delay the timing at which the supply of bleed air for leaning the mixture is interrupted when the engine is operated at a high altitude under the high loaded condition.

Abstract: A catalytic converter includes a double-walled enclosure including inner and outer shells one positioned inside the other to define an annular adiabatic space therebetween, a perforated outer sleeve positioned inside the double walled enclosure with an outer chamber defined between it and the inner shell, and a perforated inner sleeve positioned inside the perforated outer sleeve with an annular intermediate chamber defined between it and the perforated outer sleeve while defining an inner chamber at the inside thereof. The annular intermediate chamber is used to contain a bed of catalyst material. The inner shell is constituted by first and second generally cylindrical shell sections while the outer shell is constituted by first and second longitudinal sections each being of a generally semicircular cross section.

Abstract: An exhaust gas purification system for use in an internal combustion engine equipped with a dual exhaust system. The exhaust gas purification system includes a secondary air supplying port of a secondary air supplying passage opened into selected one of a first or second group of exhaust pipes, while an exhaust gas deriving port of an exhaust gas recycling passage for recycling the exhaust gases to an upstream of the carburetor throttle valve is provided in the exhaust line at a downstream from the above secondary air supplying port for effective suppression of NOx through accurate control of the amount of exhaust gases to be recycled.