The present invention relates to a gas intake device (1) for a cylinder of an internal-combustion engine. Gas intake device (1) comprises an intake pipe (2), an intake valve (3), a calibration part (4) for intake valve (3), and means for generating an aerodynamic motion of the gas in the cylinder about an axis substantially perpendicular to the axis of said cylinder. Furthermore, intersection (7) between intake pipe (2) and calibration part (4) occurs in a line nonparallel to the plane of fire face (FF).

A compression ignited combustion engine has at least one cylinder and first and second gas intake ports in a cylinder head restricting a combustion chamber. One gas intake passage leads to the two ports and is widened in a Y-shaped end influencing gas entering each port into a tangential flow in opposite direction with respect to the flow into the other port. The first intake port is designed to allow gas entering this port to continue said tangential flow so as to enter the combustion chamber in a swirl in a first rotation direction, whereas the second intake port is designed to guide gas entering this port to also enter the combustion chamber in a swirl in said first rotation direction.

The present invention relates to a gas intake device (1) for a cylinder of an internal-combustion engine. Gas intake device (1) comprises an intake pipe (2), an intake valve (3), a calibration part (4) for intake valve (3), and means for generating an aerodynamic motion of the gas in the cylinder about an axis substantially perpendicular to the axis of said cylinder. Furthermore, intersection (7) between intake pipe (2) and calibration part (4) occurs in a line nonparallel to the plane of fire face (FF).

An intake device of an internal combustion engine includes a partition, a control valve, and a third passage. The partition divides an interior of an intake pipe that couples with a combustion chamber into a first passage and a second passage. The control valve is capable of opening and closing the first passage. The third passage opens at or near a coupling site between the partition and the intake pipe on an inner face of the second passage. The third passage is configured to be capable of sucking in at least a part of a boundary layer produced at or near the coupling site by a vapor flowing through the second passage in a state in which the control valve is working in a direction of closing the first passage.

An apparatus (201) and method for controlling intake valves (23) in an internal combustion engine (5), as well as an internal combustion engine and a vehicle comprising the apparatus, and an electronic processor for performing the method is disclosed. The apparatus comprises a hydraulic system (3) configured to hydraulically actuate a first intake valve (23a) and a second intake valve (23b) of a first combustion chamber (25) of an internal combustion engine (5). The apparatus also includes a controller (9) configured to control the hydraulic system (3) in at least a first mode of operation and a second mode of operation. In the first mode of operation, the controller (9) is configured to control the hydraulic system (3) to cause lifting of the first and second intake valves (23a, 23b) of the first combustion chamber (25) during each intake stroke of a respective cylinder piston (27). In the second mode of operation, the controller (9) is configured to control the hydraulic system (3) to cause lifting of the first intake valve (23a) of the first combustion chamber (25) during an intake stroke of the respective cylinder piston (27) and disable actuation of the second intake valve (23b) of the first combustion chamber (25) during that intake stroke.

A control system for a pre-mixture compression-ignition engine is provided, configured such that in a first combustion mode, the control unit controls the fuel injection valve to have a fuel amount within a mixture gas in an outer circumferential portion of the combustion chamber larger than in the center portion, the swirl generating part to generate a swirl flow in the outer circumferential portion, and the spark plug to ignite the mixture gas in the center portion. In a second combustion mode, the control unit controls the fuel injection valve to start a fuel injection on intake stroke so that the mixture gas is formed in the entire combustion chamber, the swirl generating part so that a swirl flow becomes weaker than in the first combustion mode, and the spark plug to ignite the mixture gas before CTDC.

An apparatus that controls a swirl ratio in a diesel engine for a motor vehicle includes a first intake port that directs a first airflow into a combustion chamber, and a second intake port that directs a second airflow into the combustion chamber. The first and second intake ports are arranged to direct the first airflow and the second airflow such that a desired swirl ratio is achieved in the combustion chamber.

In an engine (1), an ignition plug (22) is arranged between a first intake port (6) and a second intake port (7). In a case where a downstream end portion (71) of the second intake port (7) is divided into a first intake port (6) side and an opposite first intake port (6) side, an inner wall surface (71a) of an opposite first intake port (6) side portion extends in a direction toward the first intake port (6) as extending from an upstream side to a downstream side of the second intake port (7).

An internal combustion engine includes an ignition plug and an electronic control unit. The electronic control unit is configured to: (i) execute a lean-burn operation in a first operation region, (ii) execute an operation in a second operation region at an air-fuel ratio lower than an air-fuel ratio during the lean-burn operation, and (iii) control a gas flow in a cylinder so that a ratio of a change in a gas flow speed around the ignition plug during ignition to a change in an engine rotation speed in a first engine rotation speed region within the first operation region is smaller than the ratio in a second engine rotation speed region within the second operation region.

In an engine (1), when an intake valve (16) opens, a downstream end portion (61) of a first intake port (6) extends to direct to between a shade back (162a) positioned on a cylinder axis (C) side with respect to a valve stem (161) and a ceiling surface (51) facing the shade back (162a). As viewed in a section perpendicular to a direction perpendicular to an intake air flow direction, a second intake port side inner wall surface (61a) at the downstream end portion (61) of the first intake port (6) curves apart from a second intake port (7) in a direction from an exhaust side to an intake side as compared to the shape of an opposite second intake port side inner wall surface (61b) mirror-reversed to a second intake port (7) side.