Abstract: Provided is an internal combustion engine including two intake valves for each cylinder, the internal combustion engine including: a fixed cam for driving one of the two intake valves with a lift characteristic having a valve opening timing close to a top dead center; a variable valve actuation mechanism capable of changing, in accordance with an engine running condition, lift characteristics between a low-lift characteristic having an event angle and a lift amount each being smaller than an event angle and a lift amount of the fixed cam, and a high-lift characteristic having the event angle and the lift amount each being larger than the event angle and the lift amount of the fixed cam; and a variable cam for driving another of the two intake valves, the variable cam including the variable valve actuation mechanism, in which the variable valve actuation mechanism is configured to set the lift characteristic of the variable cam so as to obtain a valve opening timing on a retard side relative to the valve openi

Abstract: Provided is an internal combustion engine including two intake valves for each cylinder, the internal combustion engine including: a fixed cam for driving one of the two intake valves with a lift characteristic having a valve opening timing close to a top dead center; a variable valve actuation mechanism capable of changing, in accordance with an engine running condition, lift characteristics between a low-lift characteristic having an event angle and a lift amount each being smaller than an event angle and a lift amount of the fixed cam, and a high-lift characteristic having the event angle and the lift amount each being larger than the event angle and the lift amount of the fixed cam; and a variable cam for driving another of the two intake valves, the variable cam including the variable valve actuation mechanism, in which the variable valve actuation mechanism is configured to set the lift characteristic of the variable cam so as to obtain a valve opening timing on a retard side relative to the valve openi

Abstract: An intake air control apparatus comprises an intake air path connected to a combustion chamber, and an intake airflow control device having a first opening deviated in one direction when viewed from an axial direction of the intake air path by partially closing a cross-section of a flow path of the intake air path, and that controls distribution of an intake airflow by deviating the intake airflow downstream of the first opening to a side in which the first opening is formed, the intake airflow control device having a second opening of smaller opening area than that of the first opening, and deviated in an opposite side to the side in which the first opening is formed and at a location away from an intake air path wall.

Abstract: An intake air control apparatus comprises an intake air path connected to a combustion chamber, and an intake airflow control device having a first opening deviated in one direction when viewed from an axial direction of the intake air path by partially closing a cross-section of a flow path of the intake air path, and that controls distribution of an intake airflow by deviating the intake airflow downstream of the first opening to a side in which the first opening is formed, the intake airflow control device having a second opening of smaller opening area than that of the first opening, and deviated in an opposite side to the side in which the first opening is formed and at a location away from an intake air path wall.

Abstract: An internal combustion engine includes an intake port leading to an engine cylinder. The intake port is divided into first and second passage section by a partition extending in the intake port in a longitudinal direction of the intake port. A gas motion control valve is arranged to open and close an upstream end of the second passage section. A connection passage connects an upstream end portion of the second passage section to the first passage section. A bulge is formed in a first part of a circumferential region surrounding the downstream port end so as to prevent air from being drawn from the cylinder into the second passage section.

Abstract: An internal combustion engine includes an intake port leading to an engine cylinder. The intake port is divided into first and second passage section by a partition extending in the intake port in a longitudinal direction of the intake port. A gas motion control valve is arranged to open and close an upstream end of the second passage section. A connection passage connects an upstream end portion of the second passage section to the first passage section. A bulge is formed in a first part of a circumferential region surrounding the downstream port end so as to prevent air from being drawn from the cylinder into the second passage section.