Abstract: An engine is provided, which includes a combustion chamber defined by a cylinder head and a piston inside a cylinder of a cylinder block, a fuel injection nozzle provided to the cylinder head and formed in a tip-end part with an injection hole from which fuel is injected into the combustion chamber, the tip-end part being exposed to the combustion chamber, and a passage-forming member formed with a passage through which the fuel injected from the injection hole passes. An outer circumferential surface of the passage-forming member contacts a combustion-chamber ceiling surface of the cylinder head, and the passage of the passage-forming member includes an enlarged part gradually increasing in a cross-sectional area thereof from an upstream side to a downstream side of the passage.

Abstract: An engine is provided, which includes a combustion chamber defined by a cylinder head and a piston inside a cylinder of a cylinder block, a fuel injection nozzle provided to the cylinder head and formed in a tip-end part with a plurality of injection holes from which fuel is injected into the combustion chamber, the tip-end part being exposed to the combustion chamber, and a passage-forming member formed with a passage through which the injected fuel passes. The injection holes include first and second injection holes, and the passage-forming member is disposed around the tip-end part of the nozzle so as to cause a difference between a speed at which fuel injected from the first injection hole flows toward a circumferential part of the combustion chamber, and a speed at which fuel injected from the second injection hole flows toward the circumferential part.

Abstract: A structure of a combustion chamber applied to an engine provided with a piston that reciprocates inside a cylinder, and a fuel supply system that supplies fuel to the combustion chamber defined by the cylinder and the piston, mixture gas of fuel from the fuel supply system and air combusting inside the combustion chamber, is provided. The structure includes a first heat insulating layer covering at least a part of a combustion chamber wall surface defining the combustion chamber and made of a material with a lower thermal conductivity than the combustion chamber wall surface, and a second heat insulating layer covering the first heat insulating layer and facing toward the combustion chamber, a thermal diffusivity of the second heat insulating layer being larger than the thermal diffusivity of the first heat insulating layer. The second heat insulating layer has a thickness less than the first heat insulating layer.

Abstract: 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.

Abstract: A control device of an engine including a cylinder, a piston, a cylinder head, and a combustion chamber is provided, which includes intake and exhaust ports, a swirl control valve provided in an intake passage connected to the intake port, a fuel injection valve attached to the cylinder head to be oriented into the center of the combustion chamber in a plan view thereof, and having first and second nozzle ports, and a control unit. The control unit includes a processor configured to execute a swirl opening controlling module to output the control signal to the swirl control valve to have a given opening at which a swirl ratio inside the combustion chamber becomes 2 or above, and a fuel injection timing controlling module to output the control signal to the fuel injector to inject fuel at a given timing at which the swirl ratio becomes 2 or above.

Abstract: A control device for a compression autoignition engine includes an engine, a state quantity setting device, a spark plug, a controller, and a sensor. The spark plug receives a control signal from the controller and ignites air-fuel mixture at predetermined ignition timing such that the ignited air-fuel mixture is combusted by flame propagation and then unburned air-fuel mixture in a combustion chamber is combusted by autoignition. The controller outputs a control signal to an injector such that preceding injection and succeeding injection are performed in a compression stroke.

Abstract: A control device for an engine is provided, which includes a fuel injector attached to the engine, a spark plug disposed to be oriented into a combustion chamber, a swirl control valve provided in an intake passage, and a controller connected to the fuel injector, the spark plug, and the swirl control valve and configured to control the fuel injector, the spark plug, and the swirl control valve. The swirl control valve closes in a given operating state of the engine. The fuel injector injects fuel after the swirl control valve is closed, between intake stroke and an intermediate stage of compression stroke. The fuel injector injects the fuel after the first fuel injection. The spark plug performs the ignition after the second fuel injection so that the mixture gas starts combustion by flame propagation and then unburned mixture gas self-ignites.

Abstract: A control system of a compression-ignition engine is provided, which includes an engine configured to cause combustion of a mixture gas inside the combustion chamber, an injector attached to the engine and configured to inject fuel into the combustion chamber, a spark plug disposed to be oriented into the combustion chamber and configured to ignite the mixture gas inside the combustion chamber, and a controller connected to the injector and the spark plug and configured to operate the engine by outputting a control signal to the injector and the spark plug, respectively. After the spark plug ignites the mixture gas to start combustion, unburned mixture gas combusts by self-ignition. The controller outputs the control signal to the injector so that a fuel injection timing is advanced when the engine operates at a high speed than at a low speed.

Abstract: A combustion control device for a compression autoignition engine includes an engine, a state quantity setting device, a spark plug, a controller, and a sensor. The spark plug receives a control signal from the controller and ignites air-fuel mixture at predetermined ignition timing such that the ignited air-fuel mixture is combusted by flame propagation and then unburned air-fuel mixture in a combustion chamber is combusted by autoignition. The controller outputs a control signal to an injector such that, in a compression stroke, fuel is injected at specific timing at which a line obtained by extending an axis of each hole of the injector overlaps with a specific portion including an opening edge of a cavity in an upper surface of a piston.

Abstract: A control device for a compression autoignition engine includes an engine, a state quantity setting device, a spark plug, a controller, and a sensor. The spark plug receives a control signal from the controller and ignites air-fuel mixture at predetermined ignition timing such that the ignited air-fuel mixture is combusted by flame propagation and then unburned air-fuel mixture in a combustion chamber is combusted by autoignition. The controller outputs a control signal to an injector such that preceding injection and succeeding injection are performed in a compression stroke.

Abstract: 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.

Abstract: A control system of a compression-ignition engine is provided, which includes an engine configured to cause combustion of mixture gas inside a combustion chamber, a spark plug, and a controller configured to operate the engine. The combustion is performed in a given mode in which, after the spark plug ignites the mixture gas to start combustion, unburned mixture gas combusts by self-ignition. The controller has a heat amount ratio changing module configured to change, according to an engine operating state, a heat amount ratio as an index relating to a ratio of a heat amount generated when the mixture gas combusts by flame propagation with respect to a total heat amount generated when the mixture gas inside the combustion chamber combusts. The controller causes the changing module to increase the heat amount ratio at a high engine speed than at a low engine speed.

Abstract: A control system of a compression-ignition engine is provided, which includes an engine, an injector, a spark plug, and a controller connected to the injector and the spark plug, and configured to operate the engine by outputting a control signal to the injector and the spark plug. After the spark plug ignites mixture gas to start combustion, unburned mixture gas combusts by self-ignition. The controller outputs the control signal to the injector to perform a first-stage injection of fuel and then a second-stage injection in which fuel is injected to at least form the mixture gas around the spark plug. The controller also outputs the control signal to the injector to control a ratio of the injection amount of the second-stage injection with respect to the injection amount of the first-stage injection to be higher at a high engine speed than at a low engine speed.

Abstract: A control device of an engine including a cylinder, a piston, a cylinder head, and a combustion chamber, is provided. The device includes intake and exhaust ports, a swirl control valve, a fuel injection valve attached to the cylinder head to be oriented into the combustion chamber and having first and second nozzle ports, and a control unit. The control unit includes a processor configured to execute a swirl opening controlling module to control the swirl control valve to have a given opening at which a swirl ratio inside the combustion chamber becomes 2 or above, and a fuel injection timing controlling module to control the fuel injection valve to inject fuel at a given timing at which the swirl ratio becomes 2 or above and a swirl flow from a lower portion to a higher portion of the combustion chamber in a side view occurs.

Abstract: A combustion control device for a compression autoignition engine includes an engine, a state quantity setting device, a spark plug, a controller, and a sensor. The spark plug receives a control signal from the controller and ignites air-fuel mixture at predetermined ignition timing such that the ignited air-fuel mixture is combusted by flame propagation and then unburned air-fuel mixture in a combustion chamber is combusted by autoignition. The controller outputs a control signal to an injector such that, in a compression stroke, fuel is injected at specific timing at which a line obtained by extending an axis of each hole of the injector overlaps with a specific portion including an opening edge of a cavity in an upper surface of a piston.

Abstract: A control device of an engine including a cylinder, a piston, a cylinder head, and a combustion chamber is provided, which includes intake and exhaust ports, a swirl control valve provided in an intake passage connected to the intake port, a fuel injection valve attached to the cylinder head to be oriented into the center of the combustion chamber in a plan view thereof, and having first and second nozzle ports, and a control unit. The control unit includes a processor configured to execute a swirl opening controlling module to output the control signal to the swirl control valve to have a given opening at which a swirl ratio inside the combustion chamber becomes 2 or above, and a fuel injection timing controlling module to output the control signal to the fuel injector to inject fuel at a given timing at which the swirl ratio becomes 2 or above.

Abstract: A control device for an engine is provided, which includes a fuel injector attached to the engine, a spark plug disposed to be oriented into a combustion chamber, a swirl control valve provided in an intake passage, and a controller connected to the fuel injector, the spark plug, and the swirl control valve and configured to control the fuel injector, the spark plug, and the swirl control valve. The swirl control valve closes in a given operating state of the engine. The fuel injector injects fuel after the swirl control valve is closed, between intake stroke and an intermediate stage of compression stroke. The fuel injector injects the fuel after the first fuel injection. The spark plug performs the ignition after the second fuel injection so that the mixture gas starts combustion by flame propagation and then unburned mixture gas self-ignites.

Abstract: A control device of an engine including a cylinder, a piston, a cylinder head, and a combustion chamber, is provided. The device includes intake and exhaust ports, a swirl control valve, a fuel injection valve attached to the cylinder head to be oriented into the combustion chamber and having first and second nozzle ports, and a control unit. The control unit includes a processor configured to execute a swirl opening controlling module to control the swirl control valve to have a given opening at which a swirl ratio inside the combustion chamber becomes 2 or above, and a fuel injection timing controlling module to control the fuel injection valve to inject fuel at a given timing at which the swirl ratio becomes 2 or above and a swirl flow from a lower portion to a higher portion of the combustion chamber in a side view occurs.

Abstract: A control system of a compression-ignition engine is provided, which includes an engine configured to cause combustion of a mixture gas inside the combustion chamber, an injector attached to the engine and configured to inject fuel into the combustion chamber, a spark plug disposed to be oriented into the combustion chamber and configured to ignite the mixture gas inside the combustion chamber, and a controller connected to the injector and the spark plug and configured to operate the engine by outputting a control signal to the injector and the spark plug, respectively. After the spark plug ignites the mixture gas to start combustion, unburned mixture gas combusts by self-ignition. The controller outputs the control signal to the injector so that a fuel injection timing is advanced when the engine operates at a high speed than at a low speed.

Abstract: A control system of a compression-ignition engine is provided, which includes an engine, an injector, a spark plug, and a controller connected to the injector and the spark plug, and configured to operate the engine by outputting a control signal to the injector and the spark plug. After the spark plug ignites mixture gas to start combustion, unburned mixture gas combusts by self-ignition. The controller outputs the control signal to the injector to perform a first-stage injection of fuel and then a second-stage injection in which fuel is injected to at least form the mixture gas around the spark plug. The controller also outputs the control signal to the injector to control a ratio of the injection amount of the second-stage injection with respect to the injection amount of the first-stage injection to be higher at a high engine speed than at a low engine speed.