摘要:
An emission control system for an internal combustion engine (1) is provided with a catalyst (4) disposed in an exhaust passage (3) of the internal combustion engine (1) for purifying an exhaust gas that enters the catalyst (4); engine operating state detecting means (15) for detecting an engine operating state of the internal combustion engine (1); catalyst temperature raising means capable of raising a temperature of the catalyst (4) in a plurality of modes; and selecting means (11) for selecting one mode from the plurality of modes based on a value detected by the engine operating state detecting means such that the catalyst temperature is raised. When the internal combustion engine is in a low load state, the catalyst temperature raising means raises the temperature of the catalyst in a first mode selected from the plurality of modes, by increasing an amount of a main fuel injected into the internal combustion engine (1) so as to make an air/fuel ratio closer to a stoichiometric value, and by adding a fuel into the exhaust passage (3). When the internal combustion engine is in an intermediate load state, the catalyst temperature raising means raises the temperature of the catalyst in a second mode selected from the plurality of modes, by injecting an additional fuel after injecting the main fuel into the internal combustion engine (1), and by adding the fuel into the exhaust passage (3). When the internal combustion engine is in a high load state, the catalyst temperature raising means raises the catalyst temperature in a third mode selected from the plurality of modes, by adding the fuel into the exhaust passage (3).
摘要:
In the fuel injection system, fuel is supplied to a common rail from a high pressure fuel pump, and injected into the cylinders of an engine, from the common rail, via fuel injection valves. An electronic control unit (ECU) of the engine controls the pressure in the common rail at a value determined by the operating conditions of the engine. The ECU further detects the pressure and the temperature of the fuel in the common rail, and determines the bulk modulus of elasticity of the fuel based on the pressure and the temperature of the fuel. The ECU calculates an estimated value of the pressure change in the common rail during the fuel injection period using the determined bulk modulus. If the difference between the estimated value of the pressure change and the pressure change actually measured during the fuel injection period is large, the ECU determines that the fuel injection system has failed. Since the estimated value of the pressure change is calculated based on the bulk modulus of elasticity which is determined in accordance with the actual pressure and temperature of the fuel, the accurate estimated value is obtained even if the pressure and the temperature of the fuel in the common rail change over a very wide range.
摘要:
A device for purifying the exhaust gas of an internal combustion engine is disclosed. The device comprises a particulate trap disposed in the engine exhaust system, an exhaust gas recirculation passage communicating the upstream of the particulate trap in the engine exhaust system with the engine intake system, a control valve for controlling the amount of exhaust gas recirculated through the exhaust gas recirculation passage to be an optimum amount in accordance with an engine operating condition. In the device, an amount of the fresh air introduced into the engine intake system during a fuel-cut is detected, and an amount of particulate trapped by the particulate trap is estimated on the basis of the amount of fresh air detected after the control valve is opened to a predetermined opening degree.
摘要:
An exhaust gas purification device of an internal combustion engine in accordance with the present invention is provided with a NOx absorbent (70), which is provided in an exhaust passage (106,107) of the internal combustion engine (101), for occluding nitrogen oxide when an oxygen concentration of inflow exhaust gas is high and emitting the occluded nitrogen oxide when the oxygen concentration of the inflow exhaust gas falls, and poisoning eliminating means for, if necessity for eliminating poisoning of the NOx absorbent due to oxide arises, executing poisoning elimination processing of the NOx absorbent when the internal combustion engine is in a decelerating operation state and an idling operation state, and further provided with a particulate filter (20) on which a NOx absorbent is carried and poisoning eliminating means for, if necessity for eliminating poisoning of the particulate filter due to oxide and/or due to particulate matters arises, executing poisoning elimination processing of the particulate filter on condition that a decelerating operation state of the internal combustion engine is detected.
摘要:
A device for purifying the exhaust gas of an internal combustion engine is disclosed. The device comprises a particulate trap disposed in the engine exhaust system, an exhaust gas recirculation passage communicating the upstream of the particulate trap in the engine exhaust system with the engine intake system, a control valve for controlling the amount of exhaust gas recirculated through the exhaust gas recirculation passage to be an optimum amount in accordance with an engine operating condition. In the device, an amount of the fresh air introduced into the engine intake system during a fuel-cut is detected, and an amount of particulate trapped by the particulate trap is estimated on the basis of the amount of fresh air detected after the control valve is opened to a predetermined opening degree.