Abstract: A first output limit value is determined as an intersection point of a knock-limit output line which is set according to an exhaust gas recirculation rate and ignition timing and an exhaust-temperature-limit output line which is set according to the exhaust gas recirculation rate and ignition timing; a second output limit value is determined as an intersection point of the knock-limit output line and an air-quantity-limit output line which is set according to the exhaust gas recirculation rate, ignition timing and atmospheric pressure; and a third output limit value is determined as an intersection point of the knock-limit output line and a thermal-management-limit output line which is set according to the exhaust gas recirculation rate, ignition timing and vehicle running speed. A value of the exhaust gas recirculation rate at which the condition “P1?P2 or P1?P3” is satisfied is set as a target exhaust gas recirculation rate.

Abstract: A first output limit value is determined as an intersection point of a knock-limit output line which is set according to an exhaust gas recirculation rate and ignition timing and an exhaust-temperature-limit output line which is set according to the exhaust gas recirculation rate and ignition timing; a second output limit value is determined as an intersection point of the knock-limit output line and an air-quantity-limit output line which is set according to the exhaust gas recirculation rate, ignition timing and atmospheric pressure; and a third output limit value is determined as an intersection point of the knock-limit output line and a thermal-management-limit output line which is set according to the exhaust gas recirculation rate, ignition timing and vehicle running speed. A value of the exhaust gas recirculation rate at which the condition “P1?P2 or P1?P3” is satisfied is set as a target exhaust gas recirculation rate.

Abstract: In a control method of an internal combustion engine including a fuel injection valve having a plurality of injection holes and adapted to directly inject a fuel into a cylinder and an ignition plug adapted to generate a plug discharging channel, after fuel injection is performed, spark ignition is performed while turbulence in an air flow is generated by the fuel injection by an ignition plug disposed so that a discharging region is sandwiched by fuel sprays injected from the two adjacent injection holes and located within a range where the turbulence in the air flow is generated.

Abstract: A control method of an internal combustion engine including a spark plug and a fuel injection valve includes starting electric discharge of the spark plug after a gas flow in a direction from a side of the fuel injection valve toward a side of the spark plug is generated at a position of an electric discharge gap of the spark plug due to spray of the fuel injected from the fuel injection valve.

Abstract: A control unit (8) calculates a temperature difference (?Tg). The temperature difference (?Tg) is a value obtained by subtracting the temperature (Tg) of a GPF (22) from a target GPF temperature (Tgt). If the temperature difference (?Tg) is less than or equal to zero, the control unit (8) implements a fuel economy-oriented conventional control. If the temperature difference (?Tg) is greater than zero, the control unit (8) implements a filter temperature-increasing control. The filter temperature-increasing control causes the exhaust temperature to be increased so that the temperature (Tg) of the GPF (22) becomes greater than or equal to the target GPF temperature (Tgt).

Abstract: A control method for internal combustion engine with a fuel injection valve configured to directly inject fuel into a cylinder and an ignition plug configured to directly spark-ignite the fuel injected from the fuel injection valve includes comparing an actual behavior, which is an actual changing behavior of an engine revolution speed at an engine start, to a reference behavior set in advance, and switching from stratified combustion in which a fuel spray injected from the fuel injection valve and staying around the ignition plug is directly spark-ignited to homogeneous combustion in which a homogeneous air-fuel mixture is formed in a combustion chamber and the fuel is burned and increasing a mechanical compression ratio of the internal combustion engine as compared to the case where the actual behavior and the reference behavior match if the actual behavior is different from the reference behavior.

Abstract: A control unit (8) calculates a temperature difference (?Tg). The temperature difference (?Tg) is a value obtained by subtracting the temperature (Tg) of a GPF (22) from a target GPF temperature (Tgt). If the temperature difference (?Tg) is less than or equal to zero, the control unit (8) implements a fuel economy-oriented conventional control. If the temperature difference (?Tg) is greater than zero, the control unit (8) implements a filter temperature-increasing control. The filter temperature-increasing control causes the exhaust temperature to be increased so that the temperature (Tg) of the GPF (22) becomes greater than or equal to the target GPF temperature (Tgt).

Abstract: A spark ignition internal combustion engine includes: intake and exhaust valves disposed at a ceiling part of a combustion chamber; and a fuel injection valve including a tip end portion including injection holes, and being structured to inject fuel through the injection holes toward a crown of a piston, wherein the tip end portion of the fuel injection valve is arranged in a region of the ceiling part surrounded by the intake and exhaust valves. A fuel injection control includes: determining a tip end portion fuel temperature directly or indirectly, which is a temperature of fuel at the tip end portion of the fuel injection valve; and setting a fuel injection timing advanced, in response to a condition that the tip end portion fuel temperature is higher than a temperature threshold value, wherein the temperature threshold value relates to flash boiling of fuel at the injection holes.

Abstract: A control method of an internal combustion engine including a spark plug and a fuel injection valve includes starting electric discharge of the spark plug after a gas flow in a direction from a side of the fuel injection valve toward a side of the spark plug is generated at a position of an electric discharge gap of the spark plug due to spray of the fuel injected from the fuel injection valve.

Abstract: A control method for internal combustion engine with a fuel injection valve configured to directly inject fuel into a cylinder and an ignition plug configured to directly spark-ignite the fuel injected from the fuel injection valve includes comparing an actual behavior, which is an actual changing behavior of an engine revolution speed at an engine start, to a reference behavior set in advance, and switching from stratified combustion in which a fuel spray injected from the fuel injection valve and staying around the ignition plug is directly spark-ignited to homogeneous combustion in which a homogeneous air-fuel mixture is formed in a combustion chamber and the fuel is burned and increasing a mechanical compression ratio of the internal combustion engine as compared to the case where the actual behavior and the reference behavior match if the actual behavior is different from the reference behavior.

Abstract: A direct fuel injection engine including an ignition plug and a fuel injection valve arranged to be capable of injecting a fuel directly in a cylinder is controlled. The engine has a predetermined operation region in which an excess air ratio of an air-fuel mixture is set in a vicinity of 2. In a first region on a low load side of the predetermined operation region, a homogenous air-fuel mixture having the excess air ratio at a first predetermined value in the vicinity of 2 is formed upon combustion, and in a second region on a load side higher than the first region, a stratified air-fuel mixture having the excess air ratio at a second predetermined value in the vicinity of 2 is formed upon combustion.

Abstract: A spark ignition internal combustion engine includes: intake and exhaust valves disposed at a ceiling part of a combustion chamber; and a fuel injection valve including a tip end portion including injection holes, and being structured to inject fuel through the injection holes toward a crown of a piston, wherein the tip end portion of the fuel injection valve is arranged in a region of the ceiling part surrounded by the intake and exhaust valves. A fuel injection control includes: determining a tip end portion fuel temperature directly or indirectly, which is a temperature of fuel at the tip end portion of the fuel injection valve; and setting a fuel injection timing advanced, in response to a condition that the tip end portion fuel temperature is higher than a temperature threshold value, wherein the temperature threshold value relates to flash boiling of fuel at the injection holes.

Abstract: A direct fuel injection engine including an ignition plug and a fuel injection valve arranged to be capable of injecting a fuel directly in a cylinder is controlled. The engine has a predetermined operation region in which an excess air ratio of an air-fuel mixture is set in a vicinity of 2. In a first region on a low load side of the predetermined operation region, a homogenous air-fuel mixture having the excess air ratio at a first predetermined value in the vicinity of 2 is formed upon combustion, and in a second region on a load side higher than the first region, a stratified air-fuel mixture having the excess air ratio at a second predetermined value in the vicinity of 2 is formed upon combustion.

Abstract: In a control method of an internal combustion engine including a fuel injection valve having a plurality of injection holes and adapted to directly inject a fuel into a cylinder and an ignition plug adapted to generate a plug discharging channel, after fuel injection is performed, spark ignition is performed while turbulence in an air flow is generated by the fuel injection by an ignition plug disposed so that a discharging region is sandwiched by fuel sprays injected from the two adjacent injection holes and located within a range where the turbulence in the air flow is generated.