Abstract: An exhaust emission control system is provided, which includes a NOx storage catalyst provided in an exhaust passage of an engine and configured to store NOx, a urea SCR catalyst provided in the exhaust passage, downstream of the NOx storage catalyst, and a NOx reduction controlling module configured to set a NOx reduction condition and, when the NOx reduction condition is satisfied, performs NOx reduction processing in which an air-fuel ratio of exhaust gas is set to be one of near a stoichiometric air-fuel ratio and rich, and the NOx stored in the NOx storage catalyst is reduced, the NOx reduction condition being set looser for the NOx reduction processing performed the first time after the engine is started than the NOx reduction processing performed the second and subsequent times after the engine is started.

Abstract: An exhaust emission control system of an engine including a NOx catalyst disposed in an exhaust passage and for storing NOx within exhaust gas when an air-fuel ratio of the exhaust gas is lean, and reducing the stored NOx when the air-fuel ratio is approximately stoichiometric or rich, is provided. The system includes a SCR catalyst disposed downstream of the NOx catalyst and for purifying NOx by causing a reaction with ammonia, and a processor configured to execute a NOx reduction controlling module for controlling the air-fuel ratio to a target ratio so that the stored NOx is reduced. The controlling module limits the performance of the NOx reduction control when a temperature of the SCR catalyst is above a given temperature and loosens the limitation in a given engine operating state in which an exhaust gas flow rate is above a given rate despite the SCR catalyst temperature.

Abstract: An exhaust emission control system of an engine, including an NOx catalyst disposed in an exhaust passage for storing NOx within exhaust gas when an air-fuel ratio of the exhaust gas is lean, and reducing the stored NOx when the air-fuel ratio is approximately stoichiometric or rich, is provided. The system includes an SCR catalyst disposed in the exhaust passage downstream of the NOx catalyst and for purifying NOx within exhaust gas by causing a reaction with ammonia, a controller executing a NOx reduction controlling module for executing a control in which the air-fuel ratio is controlled to a target air-fuel ratio so that the stored NOx is reduced, and an ammonia adsorption amount acquiring module for acquiring an ammonia adsorption amount of the SCR catalyst by detection or estimation. The NOx reduction controlling module controls the target air-fuel ratio to be leaner as the ammonia adsorption amount increases.

Abstract: An exhaust emission control system of an engine including a NOx catalyst for storing NOx within exhaust gas when an air-fuel ratio thereof is lean, and reducing the NOx when the air-fuel ratio is approximately stoichiometric or rich, the NOx catalyst also functioning as an oxidation catalyst for oxidizing HC, is provided. The system includes a SCR catalyst for purifying NOx by causing a reaction with NH3, a urea injector, and a processor configured to execute a fuel injection controlling module, and a NOx reduction controlling module for performing a NOx reduction control to enrich the air-fuel ratio to a target ratio. When the urea injection is abnormal, the NOx reduction controlling module performs an NH3-supplied NOx reduction control in which the NOx catalyst supplies NH3 to the SCR catalyst, by performing the NOx reduction control, a lean air-fuel ratio operation control, and then the NOx reduction control again.

Abstract: An exhaust emission control system of an engine is provided including a NOx catalyst for oxidizing HC and storing NOx within exhaust gas when an air-fuel ratio of the exhaust gas is lean, and reducing the NOx when the air-fuel ratio is approximately stoichiometric or rich. The system includes a SCR catalyst for purifying NOx by causing a reaction with NH3, a urea injector, a fuel injection controlling module, and a processor configured to execute a NOx reduction controlling module for performing a NOx reduction control to enrich the air-fuel ratio to reach a target ratio. When the urea injection is determined to be abnormal, the NOx reduction controlling module performs a NH3-supplied NOx reduction control in a state where a larger amount of unburned fuel than the amount of unburned fuel in the exhaust passage in the NOx reduction control is supplied to the exhaust passage.

Abstract: An exhaust emission control system of an engine is provided, which includes a NOx catalyst disposed in an exhaust passage for storing NOx within exhaust gas when an air-fuel ratio of the exhaust gas is lean, and reducing the stored NOx when the air-fuel ratio is approximately stoichiometric or rich. A processor executes a NOx reduction controlling module for performing, when the NOx stored amount exceeds a given amount, a NOx reduction control in which a fuel injector performs a post injection of fuel to continuously control the air-fuel ratio to a target ratio so that the stored NOx is reduced to be below a given amount, the target air-fuel ratio being a ratio at which the stored NOx is reducible, the post injection causing the injected fuel to combust inside a cylinder, the execution of the control permitted when an engine load is within a medium load range.

Abstract: An exhaust emission control system is provided, which includes a NOx storage catalyst provided in an exhaust passage of an engine and configured to store NOx, a urea SCR catalyst provided in the exhaust passage, downstream of the NOx storage catalyst, and a NOx reduction controlling module configured to set a NOx reduction condition and, when the NOx reduction condition is satisfied, performs NOx reduction processing in which an air-fuel ratio of exhaust gas is set to be one of near a stoichiometric air-fuel ratio and rich, and the NOx stored in the NOx storage catalyst is reduced, the NOx reduction condition being set looser for the NOx reduction processing performed the first time after the engine is started than the NOx reduction processing performed the second and subsequent times after the engine is started.

Abstract: An exhaust emission control system of an engine is provided including a NOx catalyst for oxidizing HC and storing NOx within exhaust gas when an air-fuel ratio of the exhaust gas is lean, and reducing the NOx when the air-fuel ratio is approximately stoichiometric or rich. The system includes a SCR catalyst for purifying NOx by causing a reaction with NH3, a urea injector, a fuel injection controlling module, and a processor configured to execute a NOx reduction controlling module for performing a NOx reduction control to enrich the air-fuel ratio to reach a target ratio. When the urea injection is determined to be abnormal, the NOx reduction controlling module performs a NH3-supplied NOx reduction control in a state where a larger amount of unburned fuel than the amount of unburned fuel in the exhaust passage in the NOx reduction control is supplied to the exhaust passage.

Abstract: An exhaust emission control system of an engine including a NOx catalyst disposed in an exhaust passage and for storing NOx within exhaust gas when an air-fuel ratio of the exhaust gas is lean, and reducing the stored NOx when the air-fuel ratio is approximately stoichiometric or rich, is provided. The system includes a SCR catalyst disposed downstream of the NOx catalyst and for purifying NOx by causing a reaction with ammonia, and a processor configured to execute a NOx reduction controlling module for controlling the air-fuel ratio to a target ratio so that the stored NOx is reduced. The controlling module limits the performance of the NOx reduction control when a temperature of the SCR catalyst is above a given temperature and loosens the limitation in a given engine operating state in which an exhaust gas flow rate is above a given rate despite the SCR catalyst temperature.

Abstract: An exhaust emission control system of an engine including a NOx catalyst for storing NOx within exhaust gas when an air-fuel ratio thereof is lean, and reducing the NOx when the air-fuel ratio is approximately stoichiometric or rich, the NOx catalyst also functioning as an oxidation catalyst for oxidizing HC, is provided. The system includes a SCR catalyst for purifying NOx by causing a reaction with NH3, a urea injector, and a processor configured to execute a fuel injection controlling module, and a NOx reduction controlling module for performing a NOx reduction control to enrich the air-fuel ratio to a target ratio. When the urea injection is abnormal, the NOx reduction controlling module performs an NH3-supplied NOx reduction control in which the NOx catalyst supplies NH3 to the SCR catalyst, by performing the NOx reduction control, a lean air-fuel ratio operation control, and then the NOx reduction control again.

Abstract: An exhaust emission control system of an engine, including an NOx catalyst disposed in an exhaust passage for storing NOx within exhaust gas when an air-fuel ratio of the exhaust gas is lean, and reducing the stored NOx when the air-fuel ratio is approximately stoichiometric or rich, is provided. The system includes an SCR catalyst disposed in the exhaust passage downstream of the NOx catalyst and for purifying NOx within exhaust gas by causing a reaction with ammonia, a controller executing a NOx reduction controlling module for executing a control in which the air-fuel ratio is controlled to a target air-fuel ratio so that the stored NOx is reduced, and an ammonia adsorption amount acquiring module for acquiring an ammonia adsorption amount of the SCR catalyst by detection or estimation. The NOx reduction controlling module controls the target air-fuel ratio to be leaner as the ammonia adsorption amount increases.

Abstract: An exhaust emission control system of an engine is provided, which includes a NOx catalyst disposed in an exhaust passage for storing NOx within exhaust gas when an air-fuel ratio of the exhaust gas is lean, and reducing the stored NOx when the air-fuel ratio is approximately stoichiometric or rich. A processor executes a NOx reduction controlling module for performing, when the NOx stored amount exceeds a given amount, a NOx reduction control in which a fuel injector performs a post injection of fuel to continuously control the air-fuel ratio to a target ratio so that the stored NOx is reduced to be below a given amount, the target air-fuel ratio being a ratio at which the stored NOx is reducible, the post injection causing the injected fuel to combust inside a cylinder, the execution of the control permitted when an engine load is within a medium load range.

Abstract: Provided is a system where a composite catalyst into which an LNT catalyst and an oxidation catalyst are combined, a catalyzed particulate filter, an injector configured to inject a urea water solution into an exhaust gas passage, and an SCR catalyst are arranged in this order in an upstream-to-downstream direction of the flow of the exhaust gas.

Abstract: Provided is a system where a composite catalyst into which an LNT catalyst and an oxidation catalyst are combined, a catalyzed particulate filter, an injector configured to inject a urea water solution into an exhaust gas passage, and an SCR catalyst are arranged in this order in an upstream-to-downstream direction of the flow of the exhaust gas.

Abstract: A diesel engine is provided, which includes an engine body to be supplied with fuel containing diesel fuel as its main component, a geometric compression ratio being set to 15:1 or below, a fuel injection valve arranged in the engine body so as to be oriented toward a cylinder of the engine body and for directly injecting the fuel into the cylinder, and a control module for controlling a mode of injecting the fuel into the cylinder through the fuel injection valve. The control module performs a main injection where the fuel is injected to cause a main combustion mainly including a diffusion combustion and performs a plurality of pre-stage injections where the fuel is injected prior to the main injection to cause a pre-stage combustion prior to the main combustion. The control module controls the injection mode of the injections to adjust a heat release rate.

Abstract: Disclosed is a control apparatus for a turbocharged diesel engine. The control apparatus comprises an engine start controller (10) operable, when an engine restart condition associated with a demand for vehicle start is satisfied, to execute a split-injection control to perform a main injection for injecting fuel at a timing around a top dead center of a compression stroke, and a post injection for injecting fuel in an expansion stroke following the main injection, during the engine restart control, and, when an engine restart condition nonassociated with the demand for vehicle start is satisfied, to execute the engine restart control to perform only the main injection without executing the split-injection control. This makes it possible to optimize the engine restart control to be execute in response to satisfaction of the engine restart condition, depending on the presence or absence of the demand for vehicle start.

Abstract: The invention relates to a control method for an internal combustion engine system, capable of preventing an internal combustion engine in a state after being automatically stopped, from falling into an unrestartable state. Upon satisfaction of a given automatic stop condition, the engine 10 being running is automatically stopped (Step 11). A value of current IEBAT flowing out of a starter battery 520 is compared with a given current value IEBAT—TH, in an automatically stopped state of the engine 10 (Step S30) to diagnosis a discharging status of the starter battery 520. If a result of the diagnosis indicates that the value of current IEBAT flowing out of the starter battery 520 is greater than the given current value IEBAT—TH, it is determined that a post-attached load is detected, and the engine 10 is restarted irrespective of the satisfaction or non-satisfaction of a given restart condition.

Abstract: A diesel engine is provided, which includes an engine body to be supplied with fuel containing diesel fuel as its main component, a geometric compression ratio being set to 15:1 or below, a fuel injection valve arranged in the engine body so as to be oriented toward a cylinder of the engine body and for directly injecting the fuel into the cylinder, and a control module for controlling a mode of injecting the fuel into the cylinder through the fuel injection valve. The control module performs a main injection where the fuel is injected to cause a main combustion mainly including a diffusion combustion and performs a plurality of pre-stage injections where the fuel is injected prior to the main injection to cause a pre-stage combustion prior to the main combustion. The control module controls the injection mode of the injections to adjust a heat release rate.

Abstract: Disclosed is a control apparatus for a turbocharged diesel engine. The control apparatus comprises an engine start controller (10) operable, when an engine restart condition associated with a demand for vehicle start is satisfied, to execute a split-injection control to perform a main injection for injecting fuel at a timing around a top dead center of a compression stroke, and a post injection for injecting fuel in an expansion stroke following the main injection, during the engine restart control, and, when an engine restart condition nonassociated with the demand for vehicle start is satisfied, to execute the engine restart control to perform only the main injection without executing the split-injection control. This makes it possible to optimize the engine restart control to be execute in response to satisfaction of the engine restart condition, depending on the presence or absence of the demand for vehicle start.

Abstract: In a process of automatically stopping a diesel engine upon fulfillment of automatic engine stop conditions, an ECU cuts off fuel injection when the engine speed equals a preset first engine speed N1. The ECU limits the amount of intake air at the first engine speed N1 and, then, increases the amount of intake air at a point in time when the engine speed equals a second engine speed N2, at which point a piston in a cylinder which will be on a compression stroke at engine stop is expected to transfer to a last intake stroke, so that the piston in the compression stroke cylinder at engine stop stops at a point within a specified range closer to the bottom dead center than a piston in a cylinder which will be on an expansion stroke at engine stop.