Abstract: To improve the oil separation performance in an oil separation device for an internal combustion engine. The oil separation device (10) comprises a gas liquid separation passage (56) internally defined by a lower wall, an upper wall and a pair of side walls, and extending in a horizontal direction, a gas inlet (54) and a gas outlet (63) provided on either end of the gas liquid separation passage, a plurality of lower partition walls (56H) projecting upward from the lower wall, and a plurality of upper partition walls (56J) projecting downward from the upper wall. The lower partition walls and the upper partition wall are tilted with respective the length wise direction in plan view so as to define a spiral passage. The lower wall is inclined with respect to a horizontal plane such that an upstream part of the lower wall is lower than a downstream part of the lower wall with respect to a direction of the swirl flow.

Abstract: To improve the oil separation performance in an oil separation device for an internal combustion engine. The oil separation device (10) comprises a gas liquid separation passage (56) internally defined by a lower wall, an upper wall and a pair of side walls, and extending in a horizontal direction, a gas inlet (54) and a gas outlet (63) provided on either end of the gas liquid separation passage, a plurality of lower partition walls (56H) projecting upward from the lower wall, and a plurality of upper partition walls (56J) projecting downward from the upper wall. The lower partition walls and the upper partition wall are tilted with respective the length wise direction in plan view so as to define a spiral passage. The lower wall is inclined with respect to a horizontal plane such that an upstream part of the lower wall is lower than a downstream part of the lower wall with respect to a direction of the swirl flow.

Abstract: To improve the oil separation performance in an oil separation device for an internal combustion engine. The oil separation device (10) comprises a gas liquid separation passage (56) internally defined by a lower wall, an upper wall and a pair of side walls, and extending in a horizontal direction, a gas inlet (54) and a gas outlet (63) provided on either end of the gas liquid separation passage, a plurality of lower partition walls (56H) projecting upward from the lower wall, and a plurality of upper partition walls (56J) projecting downward from the upper wall. The lower partition walls and the upper partition wall are tilted with respective the length wise direction in plan view so as to define a spiral passage. The lower wall is inclined with respect to a horizontal plane such that an upstream part of the lower wall is lower than a downstream part of the lower wall with respect to a direction of the swirl flow.

Abstract: To improve the oil separation performance in an oil separation device for an internal combustion engine. The oil separation device (10) comprises a gas liquid separation passage (56) internally defined by a lower wall, an upper wall and a pair of side walls, and extending in a horizontal direction, a gas inlet (54) and a gas outlet (63) provided on either end of the gas liquid separation passage, a plurality of lower partition walls (56H) projecting upward from the lower wall, and a plurality of upper partition walls (56J) projecting downward from the upper wall. The lower partition walls and the upper partition wall are tilted with respective the length wise direction in plan view so as to define a spiral passage. The lower wall is inclined with respect to a horizontal plane such that an upstream part of the lower wall is lower than a downstream part of the lower wall with respect to a direction of the swirl flow.

Abstract: A control system for an internal combustion engine having a throttle valve disposed in an intake passage of the engine is provided. A wide-open intake air amount, which is an intake air amount corresponding to a state where the throttle valve is fully opened, is calculated according to the engine rotational speed, and a theoretical intake air amount, which is an intake air amount corresponding to a state where no exhaust gas of the engine is recirculated to a combustion chamber of the engine, is calculated according to the wide-open intake air amount and the intake pressure. An intake air amount of the engine is detected or estimated, and an amount of the evaporative fuel/air mixture supplied through the evaporative fuel passage to the intake passage is calculated. An intake gas amount is calculated by correcting the intake air amount using the evaporative fuel/air mixture amount, and an exhaust gas recirculation ratio is calculated using the theoretical intake air amount and the intake gas amount.

Abstract: A control apparatus for an internal combustion engine having a throttle valve disposed in an intake passage of the engine is provided. A wide-open intake air amount, which is an intake air amount corresponding to a state where the throttle valve is fully opened, is calculated, and a theoretical intake air amount, which is an intake air amount corresponding to a state where no exhaust gas of the engine is recirculated to a combustion chamber of the engine, is calculated according to the wide-open intake air amount and the intake pressure. An air-fuel ratio correction amount and a learning value thereof are calculated according to the detected air-fuel ratio, and a reference intake air amount is calculated using the intake pressure, the engine rotational speed, the air-fuel ratio correction amount, and the learning value.

Abstract: A control apparatus for an internal combustion engine having a throttle valve disposed in an intake passage of the engine is provided. A wide-open intake air amount, which is an intake air amount corresponding to a state where the throttle valve is fully opened, is calculated, and a theoretical intake air amount, which is an intake air amount corresponding to a state where no exhaust gas of the engine is recirculated to a combustion chamber of the engine, is calculated according to the wide-open intake air amount and the intake pressure. An air-fuel ratio correction amount and a learning value thereof are calculated according to the detected air-fuel ratio, and a reference intake air amount is calculated using the intake pressure, the engine rotational speed, the air-fuel ratio correction amount, and the learning value.

Abstract: A frequency spectrum analyzing apparatus for performing a frequency spectrum analysis with respect to a detected value of an operating parameter of an internal combustion engine in synchronism with rotation of the engine, is provided. The operating parameter is sampled at predetermined time intervals, and the sampled value is converted to a digital value. Intensities of first and second elements are calculated with respect to a predetermined number of the sampled values, wherein the first and second elements respectively correspond to a plurality of frequency components contained in the detected value, and a phase of the second element differs from a phase of the first element by 90 degrees. Frequency component intensities corresponding to the plurality of frequencies are calculated in synchronism with rotation of the engine, using the first element intensities and the second element intensities.

Abstract: A frequency spectrum analyzing apparatus for performing a frequency spectrum analysis with respect to a detected value of an operating parameter of an internal combustion engine in synchronism with rotation of the engine, is provided. The operating parameter is sampled at predetermined time intervals, and a sampled value is converted to a digital value. Intensities of first and second elements are calculated with respect to a predetermined number of the sampled values. The first elements and second elements respectively correspond to a plurality of frequency components contained in the detected value, and a phase of the second element differs from a phase of the first element by 90 degrees. Frequency component intensities corresponding to the plurality of frequency components are calculated in synchronism with rotation of the engine, using the first element intensities and the second element intensities.

Abstract: An ignition timing control system for an internal combustion engine, for controlling an ignition timing of the engine, is provided. A charging efficiency of the engine is calculated according to the intake air flow rate and the engine rotational speed which are detected, and a knock limit ignition timing is calculated according to the engine rotational speed and the charging efficiency. A knock correction value is calculated according to the knocking detection result by a knock sensor, and a learning parameter table, in which first and second learning parameters are set, is updated based on the engine rotational speed and the knock correction value when the knocking is detected. The learning parameter table is retrieved according to the engine rotational speed, to calculate the first and second learning parameters.

Abstract: A control system for an internal combustion engine having a throttle valve disposed in an intake passage of the engine is provided. A wide-open intake air amount, which is an intake air amount corresponding to a state where the throttle valve is fully opened, is calculated according to the engine rotational speed, and a theoretical intake air amount, which is an intake air amount corresponding to a state where no exhaust gas of the engine is recirculated to a combustion chamber of the engine, is calculated according to the wide-open intake air amount and the intake pressure. An intake air amount of the engine is detected or estimated, and an amount of the evaporative fuel/air mixture supplied through the evaporative fuel passage to the intake passage is calculated. An intake gas amount is calculated by correcting the intake air amount using the evaporative fuel/air mixture amount, and an exhaust gas recirculation ratio is calculated using the theoretical intake air amount and the intake gas amount.

Abstract: A knocking detecting apparatus for an internal combustion engine, which can more accurately perform the knocking determination based on frequency components of the output signal of the knock sensor, is provided. A frequency spectrum analysis of the knock sensor output signal is performed at predetermined angular intervals of the crankshaft rotation angle. Intensities of a plurality of frequency components obtained by the frequency spectrum analysis are stored as time series data. The time series data of the frequency component intensity are binarized, and it is determined whether or not a knocking has occurred based on the binarized time series data.

Abstract: A control system for an internal combustion engine having a throttle valve disposed in an intake passage of the engine is provided. A wide-open intake air amount, which is an intake air amount corresponding to a state where the throttle valve is fully opened, is calculated according to the engine rotational speed, and a theoretical intake air amount, which is an intake air amount corresponding to a state where no exhaust gas of the engine is recirculated to a combustion chamber of the engine, is calculated according to the wide-open intake air amount and the intake pressure. An actual intake air amount of the engine is detected or estimated, and an exhaust gas recirculation ratio is calculated using the theoretical intake air amount and the actual intake air amount. The engine is controlled using the calculated exhaust gas recirculation ratio.

Abstract: An ignition timing control system for an internal combustion engine, for controlling an ignition timing of the engine, is provided. A charging efficiency of the engine is calculated according to the intake air flow rate and the engine rotational speed which are detected, and a knock limit ignition timing is calculated according to the engine rotational speed and the charging efficiency. A knock correction value is calculated according to the knocking detection result by a knock sensor, and a learning parameter table, in which first and second learning parameters are set, is updated based on the engine rotational speed and the knock correction value when the knocking is detected. The learning parameter table is retrieved according to the engine rotational speed, to calculate the first and second learning parameters.

Abstract: A frequency spectrum analyzing apparatus for performing a frequency spectrum analysis with respect to a detected value of an operating parameter of an internal combustion engine in synchronism with rotation of the engine, is provided. The operating parameter is sampled at predetermined time intervals, and the sampled value is converted to a digital value. Intensities of first and second elements are calculated with respect to a predetermined number of the sampled values, wherein the first and second elements respectively correspond to a plurality of frequency components contained in the detected value, and a phase of the second element differs from a phase of the first element by 90 degrees. Frequency component intensities corresponding to the plurality of frequencies are calculated in synchronism with rotation of the engine, using the first element intensities and the second element intensities.

Abstract: A frequency spectrum analyzing apparatus for performing a frequency spectrum analysis with respect to a detected value of an operating parameter of an internal combustion engine in synchronism with rotation of the engine, is provided. The operating parameter is sampled at predetermined time intervals, and a sampled value is converted to a digital value. Intensities of first and second elements are calculated with respect to a predetermined number of the sampled values. The first elements and second elements respectively correspond to a plurality of frequency components contained in the detected value, and a phase of the second element differs from a phase of the first element by 90 degrees. Frequency component intensities corresponding to the plurality of frequency components are calculated in synchronism with rotation of the engine, using the first element intensities and the second element intensities.

Abstract: A knocking detecting apparatus for an internal combustion engine, which can more accurately perform the knocking determination based on frequency components of the output signal of the knock sensor, is provided. A frequency spectrum analysis of the knock sensor output signal is performed at predetermined angular intervals of the crankshaft rotation angle. Intensities of a plurality of frequency components obtained by the frequency spectrum analysis are stored as time series data. The time series data of the frequency component intensity are binarized, and it is determined whether or not a knocking has occurred based on the binarized time series data.