Abstract: An exhaust passage includes a main passage and bypass passage, a catalyst, an exhaust control valve, and an HC adsorbent in the bypass passage. The exhaust control valve is controlled so that, when a temperature of the catalyst is higher than a predetermined sintering occurrence temperature, the quality of HC desorbed from the HC adsorbent is greater when the air-fuel ratio of the exhaust gas flowing through the upstream exhaust passage portion is a lean air-fuel ratio compared to when it is a stoichiometric air-fuel ratio or rich air-fuel ratio, or the quality of HC desorbed from the HC adsorbent is greater when the air-fuel ratio of the exhaust gas flowing through the upstream exhaust passage portion is a larger lean air-fuel ratio compared to when it is a smaller lean air-fuel ratio.

Abstract: An exhaust passage includes a main passage and bypass passage, a catalyst, an exhaust control valve, and an HC adsorbent in the bypass passage. The exhaust control valve is controlled so that, when a temperature of the catalyst is higher than a predetermined sintering occurrence temperature, the quality of HC desorbed from the HC adsorbent is greater when the air-fuel ratio of the exhaust gas flowing through the upstream exhaust passage portion is a lean air-fuel ratio compared to when it is a stoichiometric air-fuel ratio or rich air-fuel ratio, or the quality of HC desorbed from the HC adsorbent is greater when the air-fuel ratio of the exhaust gas flowing through the upstream exhaust passage portion is a larger lean air-fuel ratio compared to when it is a smaller lean air-fuel ratio.

Abstract: An exhaust purification system of an internal combustion engine comprises an HC adsorbent 20 arranged adsorbing HC in exhaust gas, an NOx adsorbent 20 adsorbing NOx in exhaust gas, a catalyst 24 removing HC and NOx at a predetermined air-fuel ratio, an air-fuel ratio control part 31 configured to control an air-fuel ratio of exhaust gas, and an HC concentration calculating part 32 configured to calculate a concentration of HC desorbed from the HC adsorbent. A peak of a desorption temperature of HC at the HC adsorbent and a peak of a desorption temperature of NOx at the NOx adsorbent are substantially the same. The air-fuel ratio control part is configured to control an air-fuel ratio of inflowing exhaust gas flowing into the catalyst to the predetermined air-fuel ratio based on the concentration of HC calculated by the HC concentration calculating part when HC is desorbed from the HC adsorbent.

Abstract: A control device of an internal combustion engine is configured to output a predicted value of an output parameter by using a learning model if actually measured values of input parameters are input, control the internal combustion engine based on the predicted value of the output parameter, learn the learning model by using a gradient method and by using a combination of actually measured values of the input parameters and an actually measured value of the output parameter as teacher data, and adjust the learning rate so that the learning is performed by a smaller learning rate when an amount of noise superposed on an actually measured value of at least one parameter among the input parameters and the output parameter is relatively large compared with when the amount of noise superposed on the actually measured value of the parameter is relatively small.

Abstract: An exhaust purification system of an internal combustion engine 50 comprises: an adsorbent 20 adsorbing HC and NOx in exhaust gas, a catalyst 24 removing HC and NOx, an air-fuel ratio control part 31 configured to control an air-fuel ratio of exhaust gas discharged from an engine body of the internal combustion engine to the exhaust passage, and a temperature calculating part 32 configured to calculate a temperature of the adsorbent. At the adsorbent, a desorption temperature of HC is higher than a desorption temperature of NOx. The air-fuel ratio control part is configured to make the air-fuel ratio a stoichiometric air-fuel ratio when a temperature of the adsorbent is in the vicinity of the desorption temperature of NOx, then make the air-fuel ratio leaner than the stoichiometric air-fuel ratio when the temperature of the adsorbent reaches the vicinity of the desorption temperature of HC.

Abstract: A control device of an internal combustion engine is configured to output a predicted value of an output parameter by using a learning model if actually measured values of input parameters are input, control the internal combustion engine based on the predicted value of the output parameter, learn the learning model by using a gradient method and by using a combination of actually measured values of the input parameters and an actually measured value of the output parameter as teacher data, and adjust the learning rate so that the learning is performed by a smaller learning rate when an amount of noise superposed on an actually measured value of at least one parameter among the input parameters and the output parameter is relatively large compared with when the amount of noise superposed on the actually measured value of the parameter is relatively small.

Abstract: An exhaust purification system of an internal combustion engine 50 comprises: an adsorbent 20 adsorbing HC and NOx in exhaust gas, a catalyst 24 removing HC and NOx, an air-fuel ratio control part 31 configured to control an air-fuel ratio of exhaust gas discharged from an engine body of the internal combustion engine to the exhaust passage, and a temperature calculating part 32 configured to calculate a temperature of the adsorbent. At the adsorbent, a desorption temperature of HC is higher than a desorption temperature of NOx. The air-fuel ratio control part is configured to make the air-fuel ratio a stoichiometric air-fuel ratio when a temperature of the adsorbent is in the vicinity of the desorption temperature of NOx, then make the air-fuel ratio leaner than the stoichiometric air-fuel ratio when the temperature of the adsorbent reaches the vicinity of the desorption temperature of HC.

Abstract: An exhaust purification system of an internal combustion engine comprises an HC adsorbent 20 arranged adsorbing HC in exhaust gas, an NOx adsorbent 20 adsorbing NOx in exhaust gas, a catalyst 24 removing HC and NOx at a predetermined air-fuel ratio, an air-fuel ratio control part 31 configured to control an air-fuel ratio of exhaust gas, and an HC concentration calculating part 32 configured to calculate a concentration of HC desorbed from the HC adsorbent. A peak of a desorption temperature of HC at the HC adsorbent and a peak of a desorption temperature of NOx at the NOx adsorbent are substantially the same. The air-fuel ratio control part is configured to control an air-fuel ratio of inflowing exhaust gas flowing into the catalyst to the predetermined air-fuel ratio based on the concentration of HC calculated by the HC concentration calculating part when HC is desorbed from the HC adsorbent.

Abstract: An exhaust emission control device including a selective reduction catalyst; urea water as reducing agent being added in the pipe upstream of the reduction catalyst depurate NOx through reduction; an oxidation catalyst arranged in the pipe upstream of an added position of the urea water, the oxidation catalyst physically adsorbing NOx in the exhaust gas at a temperature lower than a lower active limit temperature of the reduction catalyst and discharging the adsorbed NOx at a temperature higher than a lower active limit temperature of the oxidation catalyst; and a fuel injection device for adding fuel into the exhaust gas upstream of the oxidation catalyst is disclosed. The start of the fuel addition by the fuel injection device is refrained until exhaust temperature on an inlet side of the reduction catalyst is increased to a preset temperature comparable with the lower active limit temperature of the oxidation catalyst.

Abstract: It is possible to decrease the amount of NOx emitted into the air. The amount of ammonia adsorbed on an SCR catalyst is calculated by subtracting the amount of ammonium nitrate produced on the SCR catalyst from the amount of ammonia adsorbed on the SCR catalyst at the time of starting of an internal combustion engine, and the amount of NO2 flowing into the SCR catalyst is decreased when an NOx purification rate estimated from the amount of ammonia adsorbed on the SCR catalyst is less than a threshold value compared to when the NOx purification rate is equal to or greater than the threshold value.

Abstract: The purpose is to prevent ammonia from flowing out of a NOx selective reduction catalyst when an air-fuel ratio of exhaust gas flowing into a NOx storage/reduction catalyst decreases. An NSR catalyst, a NOx sensor, and an SCR catalyst are provided in an exhaust passage in sequence from an upstream side, and a control apparatus is further provided to determine an amount of ammonia supplied to the NOx selective catalytic reduction catalyst on the basis of a detection value of the NOx sensor. When the air-fuel ratio of the exhaust gas flowing into the NOx storage/reduction catalyst is set at or below a stoichiometric air-fuel ratio, an amount of ammonia supplied from an ammonia supply apparatus relative to the detection value of the NOx sensor is decreased so as to be smaller than when the air-fuel ratio of the exhaust gas is larger than the stoichiometric air-fuel ratio.

Abstract: The present invention discloses an exhaust gas purification system for an internal combustion engine, which is provided with: a low pressure EGR mechanism that is equipped with a low pressure EGR passage and a low pressure EGR valve; a selective reduction type catalyst that is arranged in a portion of the exhaust passage downstream; a supply device which serves to supply an ammonia derived compound to said selective reduction type catalyst; and a control unit that causes said supply device to supply the ammonia derived compound when said low pressure EGR valve is in a valve open state, makes the amount of the ammonia derived compound supplied from said supply device larger in cases where an amount of the low pressure EGR gas flowing through said low pressure EGR passage is large, in comparison with the case where it is small.

Abstract: The purpose is to prevent ammonia from flowing out of a NOx selective reduction catalyst when an air-fuel ratio of exhaust gas flowing into a NOx storage/reduction catalyst decreases. An NSR catalyst, a NOx sensor, and an SCR catalyst are provided in an exhaust passage in sequence from an upstream side, and a control apparatus is further provided to determine an amount of ammonia supplied to the NOx selective catalytic reduction catalyst on the basis of a detection value of the NOx sensor. When the air-fuel ratio of the exhaust gas flowing into the NOx storage/reduction catalyst is set at or below a stoichiometric air-fuel ratio, an amount of ammonia supplied from an ammonia supply apparatus relative to the detection value of the NOx sensor is decreased so as to be smaller than when the air-fuel ratio of the exhaust gas is larger than the stoichiometric air-fuel ratio.

Abstract: It is possible to decrease the amount of NOx emitted into the air. The amount of ammonia adsorbed on an SCR catalyst is calculated by subtracting the amount of ammonium nitrate produced on the SCR catalyst from the amount of ammonia adsorbed on the SCR catalyst at the time of starting of an internal combustion engine, and the amount of NO2 flowing into the SCR catalyst is decreased when an NOx purification rate estimated from the amount of ammonia adsorbed on the SCR catalyst is less than a threshold value compared to when the NOx purification rate is equal to or greater than the threshold value.

Abstract: The present invention discloses an exhaust gas purification system for an internal combustion engine, which is provided with: a low pressure EGR mechanism that is equipped with a low pressure EGR passage and a low pressure EGR valve; a selective reduction type catalyst that is arranged in a portion of the exhaust passage downstream; a supply device which serves to supply an ammonia derived compound to said selective reduction type catalyst; and a control unit that causes said supply device to supply the ammonia derived compound when said low pressure EGR valve is in a valve open state, makes the amount of the ammonia derived compound supplied from said supply device larger in cases where an amount of the low pressure EGR gas flowing through said low pressure EGR passage is large, in comparison with the case where it is small.

Abstract: An exhaust gas purification system for an internal combustion engine, which is provided with: a selective reduction type catalyst arranged in an exhaust passage of the internal combustion engine; a low pressure EGR mechanism that is equipped with a low pressure EGR passage for introducing a part of an exhaust gas flowing through a portion of the exhaust passage downstream of a turbine of a centrifugal supercharger to a portion of an intake passage upstream of a compressor as a low pressure EGR gas, and a low pressure EGR valve for changing a channel cross section of the low pressure EGR passage; a supply device.

Abstract: An exhaust purifying device for an internal combustion engine which can restrict an influence of a measurement error in a NOx sensor provided at the downstream side of a catalyst and can optimally maintain a NOx purifying rate. The device includes a catalytic converter carrying a selective catalytic reduction catalyst provided in an exhaust passage of the engine to selectively reduce nitrogen oxides, a urea water adding valve for adding urea water to the catalyst as a reducing agent, a NOx sensor provided at the downstream side of the catalyst, and an ECU for adjusting an addition amount of the urea water adding valve based upon output of the NOx sensor, wherein a urea water addition amount adjusting process is executed under a condition that a NOx amount to be generated in the engine increases.

Abstract: An exhaust gas recirculation device of an engine (10) of the invention comprises a first exhaust gas recirculation passage (50) for connecting an exhaust passage (40) and an intake passage (30) to each other and introducing into the intake passage an exhaust gas discharged from a combustion chamber (21) to the exhaust passage, and a second exhaust gas recirculation passage (55) for connecting the exhaust passage upstream of a part of the exhaust passage connected to the first exhaust gas recirculation passage and the intake passage downstream of a part of the intake passage connected to the first exhaust gas recirculation passage to each other and introducing into the intake passage the exhaust gas discharged from the combustion chamber to the exhaust passage.

Abstract: The present invention provides an exhaust purification apparatus for an internal combustion engine which enables a decrease in NOx purification rate and possible ammonia slip to be inhibited. The apparatus includes an NOx catalyst, a urea aqueous solution addition valve serving as reducing agent adding means, and NOx sensors provided an inlet and an outlet of the NOx catalyst, respectively. When the bed temperature of the NOx catalyst is in a predetermined high-temperature region in which the amount of ammonia converted into NOx increases relatively and an NOx purification rate decreases relatively, the apparatus uses outputs from the NOx sensors to perform correction such that the actual addition amount of the urea aqueous solution addition valve reaches a target addition amount.

Abstract: An internal combustion engine, in which an NOX selective reducing catalyst (15) is arranged inside an engine exhaust passage, and aqueous urea stored in an aqueous urea tank (20) is fed to the NOX selective reducing catalyst (15) to selectively reduce the NOX. The aqueous urea tank (20) comprises a main tank (20a) and a sub tank (20b) arranged inside the main tank (20a). The aqueous urea in the sub tank (20b) is sent to an aqueous urea feed valve (17). When the aqueous urea tank (20) should be refilled with aqueous urea, the sub tank (20b) is refilled with aqueous urea. It is detected by a level sensor (40) if the aqueous urea in the aqueous urea tank (20) is refilled. When it is judged that the NOX purification rate falls below an allowable level at the time of engine operation right after the aqueous urea in the aqueous urea tank (20) has been refilled, it is judged that the refilled aqueous urea is abnormal.