Abstract: The abnormality diagnosis system 1, 1?, 1? of an ammonia detection device 46, 71 comprises: an air-fuel ratio detection device 41, 72 arranged in the exhaust passage 22 at the downstream side of the catalyst 20; an air-fuel ratio control part 51 configured to control an air-fuel ratio of exhaust gas; and an abnormality judgment part 52 configured to judge abnormality of the ammonia detection device. The air-fuel ratio control part performs rich control making the air-fuel ratio of the inflowing exhaust gas richer than a stoichiometric air-fuel ratio. The abnormality judgment part judges that the ammonia detection device is abnormal if, after start of the rich control, an output value of the ammonia detection device does not rise to a reference value before the air-fuel ratio detected by the air-fuel ratio detection device falls to a rich judged air-fuel ratio richer than a stoichiometric air-fuel ratio.

Abstract: An exhaust purification system comprises an exhaust purification catalyst 20, an NOX sensor 46, air-fuel ratio sensor 41 downstream of the catalyst 20, and a control and diagnosis device. The device alternately sets a target air-fuel ratio to a rich air-fuel ratio and a lean air-fuel ratio and switches the target air-fuel ratio from the rich air-fuel ratio to the lean air-fuel ratio when the output air-fuel ratio of the air-fuel ratio sensor becomes a rich judged air-fuel ratio or less. The device diagnoses abnormality of the catalyst based on the output of the NOX sensor. It diagnoses abnormality of the catalyst when the air-fuel ratio of the exhaust gas flowing into the catalyst is a rich air-fuel ratio, but does not diagnose abnormality of the catalyst when the air-fuel ratio of the exhaust gas flowing into the catalyst is a lean air-fuel ratio.

Abstract: The exhaust purification system of an internal combustion engine comprises: a catalyst arranged in an exhaust passage of the internal combustion engine and able to store oxygen; an ammonia detection device arranged in the exhaust passage at a downstream side of the catalyst in a direction of flow of exhaust; and an air-fuel ratio control part configured to control an air-fuel ratio of inflowing exhaust gas flowing into the catalyst to a target air-fuel ratio. The air-fuel ratio control part is configured to perform rich control making the target air-fuel ratio richer than a stoichiometric air-fuel ratio, and make the target air-fuel ratio leaner than the stoichiometric air-fuel ratio when an output value of the ammonia detection device rises to a reference value in the rich control.

Abstract: An exhaust purification system comprises an exhaust purification catalyst 20, an NOX sensor 46, air-fuel ratio sensor 41 downstream of the catalyst 20, and a control and diagnosis device. The device alternately sets a target air-fuel ratio to a rich air-fuel ratio and a lean air-fuel ratio and switches the target air-fuel ratio from the rich air-fuel ratio to the lean air-fuel ratio when the output air-fuel ratio of the air-fuel ratio sensor becomes a rich judged air-fuel ratio or less. The device diagnoses abnormality of the catalyst based on the output of the NOX sensor. It diagnoses abnormality of the catalyst when the air-fuel ratio of the exhaust gas flowing into the catalyst is a rich air-fuel ratio, but does not diagnose abnormality of the catalyst when the air-fuel ratio of the exhaust gas flowing into the catalyst is a lean air-fuel ratio.

Abstract: The exhaust purification system of an internal combustion engine 100, 100?, 100? comprises: a catalyst 20 arranged in an exhaust passage 22 and able to store oxygen; an ammonia detection device 46, 71 and an air-fuel ratio detection device 41, 72 arranged in the exhaust passage at a downstream side of the catalyst; and an air-fuel ratio control part configured to control an air-fuel ratio of exhaust gas flowing into the catalyst to a target air-fuel ratio. The air-fuel ratio control part performs rich control making the target air-fuel ratio richer than a stoichiometric air-fuel ratio, in the rich control, reduces a rich degree of the target air-fuel ratio when an output value of the ammonia detection device rises to a reference value, and ends the rich control when an air-fuel ratio detected by the air-fuel ratio detection device falls to a rich judged air-fuel ratio.

Abstract: The exhaust purification system of an internal combustion engine comprises: a catalyst arranged in an exhaust passage of the internal combustion engine and able to store oxygen; an ammonia detection device arranged in the exhaust passage at a downstream side of the catalyst in a direction of flow of exhaust; and an air-fuel ratio control part configured to control an air-fuel ratio of inflowing exhaust gas flowing into the catalyst to a target air-fuel ratio. The air-fuel ratio control part is configured to perform rich control making the target air-fuel ratio richer than a stoichiometric air-fuel ratio, and make the target air-fuel ratio leaner than the stoichiometric air-fuel ratio when an output value of the ammonia detection device rises to a reference value in the rich control.

Abstract: The abnormality diagnosis system 1, 1?, 1? of an ammonia detection device 46, 71 comprises: an air-fuel ratio detection device 41, 72 arranged in the exhaust passage 22 at the downstream side of the catalyst 20; an air-fuel ratio control part 51 configured to control an air-fuel ratio of exhaust gas; and an abnormality judgment part 52 configured to judge abnormality of the ammonia detection device. The air-fuel ratio control part performs rich control making the air-fuel ratio of the inflowing exhaust gas richer than a stoichiometric air-fuel ratio. The abnormality judgment part judges that the ammonia detection device is abnormal if, after start of the rich control, an output value of the ammonia detection device does not rise to a reference value before the air-fuel ratio detected by the air-fuel ratio detection device falls to a rich judged air-fuel ratio richer than a stoichiometric air-fuel ratio.

Abstract: An exhaust emission control system of an internal combustion engine includes: a bypass passage (22) provided in an exhaust passage (14) of the engine and arranged to bypass a main passage (16) as a part of the exhaust passage, a NOx adsorbent (28) provided in the bypass passage and adapted to adsorb at least NOx as one of components contained in exhaust gas, a channel switching device (30) that switches a channel of the exhaust gas between the main passage and the bypass passage, an adsorption control device (50) that controls the channel switching device, based on operating conditions of the engine, so as to cause the exhaust gas to flow through the bypass passage, and an adsorbing capability determining device (50) that determines, when the adsorbing capability of the NOx adsorbent degrades, whether the degradation in the adsorbing capability is a surmountable degradation from which the NOx adsorbent can recover, or an insurmountable degradation from which the NOx adsorbent cannot recover.

Abstract: An exhaust gas purification device has: a bypass passage (20) disposed in an exhaust passage (15) of an internal combustion engine (10); an adsorbent (21) which is disposed in the bypass passage (20), and adsorbs unburned components in exhaust gas at a low temperature and desorbs the adsorbed unburned components at a high temperature; and an exhaust gas purification catalyst (22) which is disposed in the exhaust passage (15) at a downstream side of a portion where the bypass passage (20) merges, and purifies unburned components in exhaust gas; and a desorption amount adjustment (19) unit that adjusts the desorption amount of unburned components adsorbed by the adsorbent (21) based on an integrated fuel cut air amount (fgs), which is an integrated value of air amount taken into a combustion chamber of the internal combustion engine (10) during execution of fuel cut.

Abstract: An object of the present invention is to provide an exhaust gas purifying apparatus for an internal combustion engine which can properly purge at least NOx of unpurified components contained in exhaust gas while considering characteristics of NOx desorbed from an adsorbent. A bypass passage 18 bypassing a main exhaust passage 12 of the internal combustion engine 10 is provided. A HC/NOx adsorbent 22 having a function of adsorbing HC and NOx is provided in the bypass passage 18. A second underfloor catalyst 30 is provided downstream of the adsorbent 22. A purge passage 26 branching off from the bypass passage 18 while connecting to an intake passage is provided. An exhaust switching valve 20 and a purge control valve 28 are provided as a flow path switching means that is capable of switching a flow target into which the exhaust gas flows between the main exhaust passage 12 and the bypass passage 18. If the purging operations are executed, the intake purging operation is first executed.

Abstract: A moisture adsorbent (32) for adsorbing moisture in exhaust gas and an NOx adsorbent (34) for adsorbing NOx are disposed in a bypass passage (30) for bypassing an exhaust passage (16) of an internal combustion engine (10). When an adsorption operation to the NOx adsorbent (34) is executed, inflow of the exhaust gas to the bypass passage (30) is allowed until the moisture amount that flows into the water adsorbent (32) reaches an allowable moisture inflow amount. The allowable moisture inflow amount is determined based on a residual moisture amount before the starting of the adsorption operation in the moisture adsorbent (32). The residual moisture amount in the water adsorbent (32) can be determined based on the temperature of the moisture adsorbent (32) at the immediately preceding execution of the purge operation.

Abstract: An exhaust gas purifying apparatus for an internal combustion engine is provided to desorb predetermined components contained in exhaust gas from an adsorption device for adsorbing the components and to purify the desorbed components, even during the stop of the internal combustion engine. A main exhaust passage and a bypass passage bypassing the main exhaust passage are provided. An exhaust switching valve is capable of switching a flow target into the exhaust gas flows between the main exhaust passage and the bypass passage. An adsorbent for adsorbing the predetermined components is provided in the bypass passage. An underfloor catalyst including a catalyst with a heater is provided at a downstream side of the bypass passage in the main exhaust passage. A pump and a heater are provided in an air supply passage which branches from the bypass passage at an upstream portion of the adsorbent.

Abstract: A main exhaust passage 42 and a first bypass passage 46 bypassing the main exhaust passage 42 are provided. An absorbent 52 having a function of absorbing HC components and NOx components contained in exhaust gas is provided in the first bypass passage 46. An underfloor catalyst 56 including a catalyst with an electric heater (EHC) 58 is provided in a main exhaust passage 42 on a downstream side of a downstream connecting portion 48b in a first bypass passage 46. A second bypass passage 62 that provides communication between the main exhaust passage 42 downstream of the underfloor catalyst 56 and the first bypass passage 46 upstream of the absorbent 52 is provided. A first exhaust switching valve 50 is provided in an upstream connecting portion 48a, and a second exhaust switching valve 68 is provided in a main exhaust passage side connecting portion 64a. A pump 66 is provided in the middle of the second bypass passage 62.

Abstract: A moisture adsorbing device 1 comprising a type Y zeolite, and an NOx adsorbing device 2 being put in place on an exhaust-gas downstream side of the moisture adsorbing device 1, and comprising a zeolite that includes a transition metal ion in the cation exchange sites are included. In NOx adsorbing apparatuses, since the less the moisture content in exhaust gases is the more the NOx adsorbing capability improves, the NO adsorbing capability in low-temperature region is improved especially by means of the combination with a moisture adsorbing device that comprises a type Y zeolite whose Al2O3 proportion is great and whose moisture adsorbing amount is great compared with the other zeolites.

Abstract: The present invention relates to an exhaust emission control device having an NOx adsorbent, and makes it possible to judge whether the performance of the NOx adsorbent is degraded temporarily or permanently. The amounts of NOx and water adsorbed by the NOx adsorbent are measured during an actual operation of an internal combustion engine. A reference line indicating the correlation between a preselected water adsorption amount and NOx adsorption amount is then referenced to determine a reference value y0 of the NOx adsorption amount that corresponds to a measured value x1 of the water adsorption amount. Next, a measured value y1 of the NOx adsorption amount is compared against the reference value y0 to output a signal in which the result of the comparison is reflected.

Abstract: In a malfunction diagnosis device for an exhaust gas purification system including an exhaust gas purification catalyst disposed in the exhaust passage of an internal combustion engine, and a reductant supply device that supplies reductant to exhaust gas that flows in an upstream side of the exhaust gas purification catalyst, the degree of degradation of the exhaust gas purification catalyst is diagnosed by comparing the timing at which the bed temperature of the exhaust gas purification catalyst starts to rise due to the heat of moisture adsorption reaction, against a normal value.

Abstract: An exhaust emission control system of an internal combustion engine includes: a bypass passage (22) provided in an exhaust passage (14) of the engine and arranged to bypass a main passage (16) as a part of the exhaust passage, a NOx adsorbent (28) provided in the bypass passage and adapted to adsorb at least NOx as one of components contained in exhaust gas, a channel switching device (30) that switches a channel of the exhaust gas between the main passage and the bypass passage, an adsorption control device (50) that controls the channel switching device, based on operating conditions of the engine, so as to cause the exhaust gas to flow through the bypass passage, and an adsorbing capability determining device (50) that determines, when the adsorbing capability of the NOx adsorbent degrades, whether the degradation in the adsorbing capability is a surmountable degradation from which the NOx adsorbent can recover, or an insurmountable degradation from which the NOx adsorbent cannot recover.

Abstract: An exhaust gas purification device has: a bypass passage (20) disposed in an exhaust passage (15) of an internal combustion engine (10); an adsorbent (21) which is disposed in the bypass passage (20), and adsorbs unburned components in exhaust gas at a low temperature and desorbs the adsorbed unburned components at a high temperature; and an exhaust gas purification catalyst (22) which is disposed in the exhaust passage (15) at a downstream side of a portion where the bypass passage (20) merges, and purifies unburned components in exhaust gas; and a desorption amount adjustment (19) unit that adjusts the desorption amount of unburned components adsorbed by the adsorbent (21) based on an integrated fuel cut air amount (fgs), which is an integrated value of air amount taken into a combustion chamber of the internal combustion engine (10) during execution of fuel cut.

Abstract: A moisture adsorbent (32) for adsorbing moisture in exhaust gas and an NOx adsorbent (34) for adsorbing NOx are disposed in a bypass passage (30) for bypassing an exhaust passage (16) of an internal combustion engine (10). When an adsorption operation to the NOx adsorbent (34) is executed, inflow of the exhaust gas to the bypass passage (30) is allowed until the moisture amount that flows into the water adsorbent (32) reaches an allowable moisture inflow amount. The allowable moisture inflow amount is determined based on a residual moisture amount before the starting of the adsorption operation in the moisture adsorbent (32). The residual moisture amount in the water adsorbent (32) can be determined based on the temperature of the moisture adsorbent (32) at the immediately preceding execution of the purge operation.

Abstract: A main exhaust passage 42 and a first bypass passage 46 bypassing the main exhaust passage 42 are provided. An absorbent 52 having a function of absorbing HC components and NOx components contained in exhaust gas is provided in the first bypass passage 46. An underfloor catalyst 56 including a catalyst with an electric heater (EHC) 58 is provided in a main exhaust passage 42 on a downstream side of a downstream connecting portion 48b in a first bypass passage 46. A second bypass passage 62 that provides communication between the main exhaust passage 42 downstream of the underfloor catalyst 56 and the first bypass passage 46 upstream of the absorbent 52 is provided. A first exhaust switching valve 50 is provided in an upstream connecting portion 48a, and a second exhaust switching valve 68 is provided in a main exhaust passage side connecting portion 64a. A pump 66 is provided in the middle of the second bypass passage 62.