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: 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 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: In a first region on a low load side of an operation region of a direct fuel injection engine, homogenous combustion is performed, while, in a second region of the operation region on a load side higher than the first region, stratified combustion is performed. In the stratified combustion, a fuel is dispersed in a cylinder by a first injection operation and a fuel is unevenly distributed in a vicinity of the ignition plug by a second injection operation. Shift control by the stratified combustion is executed at a time of shifting when an operation state of the engine has shifted from the first region to the second region, and in the shift control, a fuel in an amount larger than a target amount of the second injection operation in the second region is injected by the second injection operation and then, an injection amount of the second injection operation is decreased toward the target amount.

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 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 first region on a low load side of an operation region of a direct fuel injection engine, homogenous combustion is performed, while, in a second region of the operation region on a load side higher than the first region, stratified combustion is performed. In the stratified combustion, a fuel is dispersed in a cylinder by a first injection operation and a fuel is unevenly distributed in a vicinity of the ignition plug by a second injection operation. Shift control by the stratified combustion is executed at a time of shifting when an operation state of the engine has shifted from the first region to the second region, and in the shift control, a fuel in an amount larger than a target amount of the second injection operation in the second region is injected by the second injection operation and then, an injection amount of the second injection operation is decreased toward the target amount.

Abstract: A fuel injection control device controls a spark-ignition engine of an intra-cylindrical direct fuel injection type. The engine includes a fuel injection valve configured to directly inject a fuel to an interior of a cylinder, and a spark plug configured to ignite, by a spark, an air-fuel mixture inside the cylinder. When the injected fuel collides with a portion in a predetermined low-temperature state, the fuel is injected while changing a fuel injection condition under predetermined operating conditions so as to restrain a fuel spray from keeping colliding with the same position continuously.

Abstract: A fuel injection control device controls a spark-ignition engine of an intra-cylindrical direct fuel injection type. The engine includes a fuel injection valve configured to directly inject a fuel to an interior of a cylinder, and a spark plug configured to ignite, by a spark, an air-fuel mixture inside the cylinder. When the injected fuel collides with a portion in a predetermined low-temperature state, the fuel is injected while changing a fuel injection condition under predetermined operating conditions so as to restrain a fuel spray from keeping colliding with the same position continuously.