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).

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).

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).

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 control apparatus for a compression-ignition type engine is applied to an engine capable of carrying out partial compression ignition combustion in which an air-fuel mixture is subjected to CI combustion by self-ignition. The control apparatus creates a lean A/F environment where an air-fuel ratio as a ratio between air and fuel in a cylinder exceeds 20 and is lower than 35, or a lean G/F environment where a gas air-fuel ratio as a ratio between entire gas and the fuel in the cylinder exceeds 18 and is lower than 50 and the air-fuel ratio substantially matches a stoichiometric air-fuel ratio. Prior to planned timing of the CI combustion, in the lean A/F environment or the lean G/F environment, the control apparatus causes an ignition plug to generate a spark and to generate a high-temperature portion.

A control apparatus for a compression-ignition type engine is applied to an engine capable of carrying out partial compression ignition combustion in which an air-fuel mixture is subjected to CI combustion by self-ignition. The control apparatus creates a lean A/F environment where an air-fuel ratio as a ratio between air and fuel in a cylinder exceeds 20 and is lower than 35, or a lean G/F environment where a gas air-fuel ratio as a ratio between entire gas and the fuel in the cylinder exceeds 18 and is lower than 50 and the air-fuel ratio substantially matches a stoichiometric air-fuel ratio. Prior to planned timing of the CI combustion, in the lean A/F environment or the lean G/F environment, the control apparatus causes an ignition plug to generate a spark and to generate a high-temperature portion.

The invention is provided with an ignition control section and an injection control section. When partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of an expansion stroke to initiate SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes an injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. Timing of the preceding ignition is set to be more retarded when an engine speed is high than when the engine speed is low.

The invention is provided with an ignition control section and an injection control section. When partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of an expansion stroke to initiate SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes an injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. Timing of the preceding ignition is set to be more retarded when an engine speed is high than when the engine speed is low.

A control apparatus for an engine includes an engine, a state quantity setting device, a spark plug, and a controller. The spark plug ignites air-fuel mixture at predetermined ignition timing so that unburned air-fuel mixture combusts by autoignition after start of combustion of the air-fuel mixture by the ignition, and the controller adjusts a heat amount ratio in accordance with an operation state of the engine through change of the ignition timing, the heat amount ratio representing an index associated with a ratio of an amount of heat generated when the air-fuel mixture combusts by flame propagation with respect to a total amount of heat generated when the air-fuel mixture combusts in the combustion chamber.

A control apparatus for an engine includes an engine, a state quantity setting device, a spark plug, and a controller. The spark plug ignites air-fuel mixture at predetermined ignition timing so that unburned air-fuel mixture combusts by autoignition after start of combustion of the air-fuel mixture by the ignition, and the controller adjusts a heat amount ratio in accordance with an operation state of the engine through change of the ignition timing, the heat amount ratio representing an index associated with a ratio of an amount of heat generated when the air-fuel mixture combusts by flame propagation with respect to a total amount of heat generated when the air-fuel mixture combusts in the combustion chamber.