Abstract: A pair of particulate filters arranged in parallel in an exhaust passage and a combustion device for supplying to the filters exhaust gas having a temperature elevation capability higher than the temperature elevation capability of the engine exhaust gas able to raise the filter temperature are provided. An NOx catalyst and oxidizing substance are carried on each filter. When the NOx absorbed in an NOx catalyst should be reduced, the flow of engine exhaust gas into the filter carrying the NOx catalyst for reduction of the NOx is suppressed and a rich air-fuel ratio exhaust gas is supplied from the combustion device to the filter so that the filter temperature is maintained higher than a particulate continuous oxidation temperature in the NOx reduction temperature range.

Abstract: Exhaust emission control apparatus and method for an internal combustion engine maintain a small amount of sulfur components contained in exhaust gas flowing out of a sulfur component retainer agent even if the amount of sulfur components retained by the agent becomes great. The exhaust emission control apparatus includes a NOx retainer agent and the sulfur component retainer agent. The apparatus performs a NOx releasing process of adjusting the air-fuel ratio of exhaust gas flowing into the sulfur component retainer agent so that the air-fuel ratio of exhaust gas flowing into the NOx retainer agent becomes substantially stoichiometric or rich of stoichiometry if NOx retained by the NOx retainer agent is to be released. The apparatus prohibits the air-fuel ratio of exhaust gas flowing into the sulfur component retainer agent from becoming substantially stoichiometric or rich of stoichiometry if the amount of the sulfur components retained by the agent is at least a first predetermined amount.

Abstract: An exhaust emission purification device comprises a sulfur component holding agent arranged on the exhaust path of an internal combustion engine for holding a sulfur component, a NOx holding agent arranged downstream of the sulfur component holding agent in the exhaust gas for holding NOx and the sulfur components when the air-fuel ratio of the exhaust gas flowing thereinto is lean, and a reducing agent adding unit for adding a reducing agent to the exhaust gas flowing into the NOx holding agent. The concentration of the sulfur component contained in the reducing agent added by the reducing agent adding unit is lower than the concentration of at least the sulfur component contained in the fuel supplied to the combustion chamber of the internal combustion engine. Thus, the sulfur poisoning of the exhaust emission purifier can be avoided while at the same time reducing the fuel consumption rate.

Abstract: An exhaust emission control system for an internal combustion engine includes an exhaust passage that branches into a first exhaust branch passage and a second exhaust branch passage, which join at downstream ends thereof into a common exhaust passage, a NOx catalyst disposed in each of the exhaust branch passages, a particulate filter disposed in the common exhaust passage and located downstream of a joining point of the exhaust branch passages, and flow control valves that control the amounts of exhaust gas flowing through the respective exhaust branch passages.

Abstract: An exhaust gas purification device of an engine comprising a particulate filter arranged in an exhaust passage. An electric motor able to impart a vehicle drive power separate from the engine and able to generate electric power from the engine is provided. After the particulate filter finishes being warmed up, when the temperature of the particulate filter is low, the output torque of the engine is increased and the amount of increase of the output torque is consumed by the power generating action of the electric motor.

Abstract: An exhaust control valve (24) is arranged in an exhaust pipe (22) of an internal combustion engine. At the time of engine startup and warmup operation, the exhaust control valve (24) is substantially fully closed, the amount of injection of main fuel is increased from the optimum amount of injection at the time when the exhaust control valve is fully opened, auxiliary fuel is additionally injected during the expansion stroke, and thereby the unburned hydrocarbons exhausted into the atmosphere is greatly reduced at the time of engine startup and warmup operation.

Abstract: An exhaust gas purifier includes a particulate filter for oxidizing collected particulates, a reversing device that reverses an exhaust gas upstream side and an exhaust gas downstream side of the particulate filter. The particulate filter includes a collecting wall for collecting the particulates, which includes a first collecting surface and a second collecting surface. The first and the second collecting surfaces are alternately used for collecting the particulates by the reversing device. The catalyst device is arranged adjacent to the particulate filter at a position always being at the downstream side of the particulate filter.

Abstract: A device for purifying the exhaust gas of an internal combustion engine is disclosed. The device comprises a particulate filter carrying an active-oxygen releasing agent that can cause the sulfur poisoning, a SOx trap unit arranged upstream of the particulate filter, and a bypass means for making the exhaust gas mainly bypass said particulate filter when SOx is released from the SOx trap unit. Further, an exhaust choke valve for an exhaust brake is arranged between the SOx trap unit and the exhaust gas branch portion of the bypass means.

Abstract: An exhaust temperature raising apparatus for an internal combustion engine includes an exhaust throttle valve that adjusts an amount of flow of an exhaust gas flowing in an exhaust passage, a valve control device for controlling the exhaust throttle valve to a substantially completely closed state at a time when an amount of an unburned fuel component contained in the exhaust gas is to be reduced, an engine air-fuel ratio control device for operating the internal combustion engine at a theoretical air-fuel ratio or a fuel-excess air-fuel ratio when the exhaust throttle valve is controlled to the substantially completely closed state by the valve control device, and a secondary air supply device for supplying a secondary air to an upstream portion of the exhaust passage when the exhaust throttle valve is controlled to the substantially completely closed state by the valve control device.

Abstract: An internal combustion engine emission control apparatus includes split passages that divide exhaust gas discharged from an internal combustion engine into a plurality of streams. Emission control catalysts are provided that individually divide the exhaust gas in the split passages, and remove a component present in the exhaust gas at a high removal rate if a temperature of exhaust gas that inflows via the split passages satisfies a predetermined temperature condition. A controller changes proportions of the amounts of flow of the exhaust gas into the split passages so that the predetermined temperature condition is satisfied in at least one split passage of the split passages. Therefore, the emission control can be performed in a broad range of changing temperatures of the exhaust gas.

Abstract: There is provided an exhaust gas purification device (22) comprising a substrate used for purifying components contained in an exhaust gas discharged from an engine. The substrate has partitions (54) which define passages (50,51) and are formed of porous material having fine pores each having a predetermined average size. The end portions of the adjacent partitions (54) defining each of part of the passages (50,51) of the substrate are partially connected to each other such that the end portions (52,53) are tapered toward the outside of the substrate. The tapered end portions partially close the end opening of the corresponding passage and form a small hole (55,56) defined by the tips thereof. The size of each small hole (55,56) is smaller than the cross sectional area of the corresponding passage (50) and larger than the sizes of the fine pores of the partitions (54).

Abstract: An exhaust gas purification device having a NOx absorbent includes a by-pass passage for by-passing the NOx absorbent, an exhaust gas flow rate control portion for regulating both a flow rate of exhaust gas flowing to the NOx absorbent and the flow rate of the exhaust gas bypassing the NOx absorbent, and a reductant addition portion for adding reductant into an exhaust passage upstream of the NOx absorbent. In this device, when it is necessary to discharge sulfur components from the NOx absorbent, a temperature rise control is executed such that a temperature of the NOx absorbent becomes higher than a predetermined temperature. Next, a rich condition control is executed such that an air-fuel ratio of the exhaust gas flowing to the NOx absorbent becomes one of a substantially stoichiometric condition and a rich condition. The flow rate of the exhaust gas to the NOx absorbent during the temperature rise control is controlled so as to be higher than that during the rich condition control.

Abstract: An exhaust gas purification device of an engine comprising a particulate filter arranged in an exhaust passage. An electric motor able to impart a vehicle drive power separate from the engine and able to generate electric power from the engine is provided. After the particulate filter finishes being warmed up, when the temperature of the particulate filter is low, the output torque of the engine is increased and the amount of increase of the output torque is consumed by the power generating action of the electric motor.

Abstract: A pair of particulate filters arranged in parallel in an exhaust passage and a combustion device for supplying to the filters exhaust gas having a temperature elevation capability higher than the temperature elevation capability of the engine exhaust gas able to raise the filter temperature are provided. An NOx catalyst and oxidizing substance are carried on each filter. When the NOx absorbed in an NOx catalyst should be reduced, the flow of engine exhaust gas into the filter carrying the NOx catalyst for reduction of the NOx is suppressed and a rich air-fuel ratio exhaust gas is supplied from the combustion device to the filter so that the filter temperature is maintained higher than a particulate continuous oxidation temperature in the NOx reduction temperature range.

Abstract: An exhaust gas purifying apparatus for an internal combustion engine includes plural catalysts provided in parallel. In a case where temperatures of the catalysts need to be raised, a catalyst is selected from among the catalysts and the exhaust gas is allowed to flow in the selected catalyst. In addition, the temperature of the selected catalyst is raised without using a reducing agent when the temperatures of the catalysts are lower than a temperature range in which the reducing agent can be purified. Alternatively, the reducing agent is supplied to the selected catalyst so as to raise the temperature thereof when the temperatures of the catalysts are equal to or higher than the temperature at which the reducing agent can be purified.

Abstract: An object of the present invention is to improve reliability of exhaust emission purification in an exhaust emission purifying device having an NOx catalyst and an bypass path bypassing the NOx catalyst.

Abstract: An exhaust gas purifier includes a particulate filter for oxidizing collected particulates, a reversing device that reverses an exhaust gas upstream side and an exhaust gas downstream side of the particulate filter. The particulate filter includes a collecting wall for collecting the particulates, which includes a first collecting surface and a second collecting surface. The first and the second collecting surfaces are alternately used for collecting the particulates by the reversing device. The catalyst device is arranged adjacent to the particulate filter at a position always being at the downstream side of the particulate filter.

Abstract: An exhaust temperature raising apparatus has an exhaust throttle valve that adjusts the engine exhaust amount based on the amount of throttling, and an injector that performs main injection and a sub-injection directly into a cylinder, a combination of an ECU, the injection and the exhaust throttle valve as exhaust gas temperature increase apparatus for, during an engine warm-up, performing and controlling the exhaust throttling by the exhaust valve and performing and controlling an exhaust gas temperature increase through combustion attributed to the main injection performed in an excess-air condition and combustion attributed to the sub-injection, an exhaust gas temperature sensor that monitors a state of temperature increase of the exhaust gas caused by performance of the exhaust gas temperature increase apparatus, and the ECU as monitor abnormality detection apparatus for determining whether the exhaust gas temperature sensor has an abnormality, and the ECU as exhaust gas temperature increase stop apparat

Abstract: An exhaust purification device comprising a first catalyst and a second catalyst arranged in the engine exhaust passage downstream of the first catalyst. An exhaust control valve is arranged downstream of the second catalyst. When the reducing components in the exhaust gas should be mainly oxidized by the first catalyst, the exhaust control valve is substantially fully closed and auxiliary fuel is additionally injected into the combustion chamber. When the reducing components in the exhaust gas should be mainly oxidized by the second catalyst, the exhaust control valve is fully opened and injection of auxiliary fuel is stopped.

Abstract: An exhaust emission control system of an internal combustion engine desorbs SOx by reversing a flow of an exhaust gas through an NOx storage-reduction catalyst, of which a structure is simplified as follows. A first exhaust pipe connected to an engine is connected to a first port of an emission switching valve having four ports. A second exhaust pipe 10, through which the exhaust gas is discharged into the atmospheric air, is connected to a second port, a third exhaust pipe connected to an inlet of a catalytic converter is connected to a third port. A fourth exhaust pipe connected to an outlet of the catalytic converter 30 is connected to a fourth port. When the emission switching valve is set in a forward flow position, the first exhaust pipe is connected to the third exhaust pipe, and the second exhaust pipe is connected to the fourth exhaust pipe, whereby the exhaust gas flows toward the outlet from the inlet within the catalytic converter.