Abstract: Engine air-fuel ratio controlling means is provided to control an exhaust air-fuel ratio that is the ratio between the air contained in the exhaust gas discharged from the engine and the fuel element contained in the same exhaust gas and acting as a reducing agent at a NOx catalyst by controlling the air-fuel ratio of the gas combusted in the engine. Fuel adding means is provided upstream of the NOx catalyst in an exhaust passage to add fuel into the exhaust gas. During the SOx poisoning recovery control, when developing a state enabling SOx reduction reactions, the exhaust gas air-fuel ratio of the exhaust gas discharged from the engine and the amount of fuel added from the fuel adding means are controlled to minimize the sum of the amount of fuel injected in the engine and the amount of fuel added from the fuel adding means.

Abstract: In an internal combustion engine, a sulfur detection sample gas is generated in a sample gas generation chamber by fuel of an amount smaller than the amount of fuel fed to a combustion chamber and proportional to the amount of fuel fed to the combustion chamber. An SOx sensor having a sensor part trapping the sulfur contained in the sample gas and capable of detecting the amount of sulfur trapped in the sensor part from the property changes of the sensor part is provided. The amount of SOx that flows into the catalyst is estimated from the output value-of this SOx sensor.

Abstract: An internal combustion engine wherein an SOX trap catalyst (11) able to trap SOX contained in exhaust gas is arranged in an engine exhaust passage upstream of an NOX storing catalyst (12). When the air-fuel ratio of the exhaust gas flowing into the SOX trap catalyst (11) is switched from lean to rich to make the NOX storing catalyst (12) release the NOX, if the temperature of the SOX trap catalyst (11) is the SOX release lower limit temperature or more, rich processing making the air-fuel ratio of the exhaust gas flowing into the SOX trap catalyst (11) rich for making the NOX storing catalyst (12) release NOX is prohibited.

Abstract: In a state where the entry word “account” retrieved from a dictionary and its explanatory information have been displayed, when the entry memo “Test point to notice” is input in handwritten characters at a handwriting input unit, the entry memo is caused to correspond to the retrieved entry word “account” and then registered. When the desired entry memo “Test point to notice” is selected from a list of the registered entry memos, the entry word “account” caused to correspond to the entry memo and its explanatory information are displayed immediately. Accordingly, as with a paper dictionary, an entry memo in which handwritten characters have been written as needed is related to the desired entry word and its explanatory information. Using the entry memo data as if it were a sticky note enables the desired entry word to be displayed easily and quickly.

Abstract: An engine exhaust passage has an SOx trapping catalyst (11), a particulate filter (13) holding an NOx storing/reducing catalyst, and an NOx storing/reducing catalyst (15) forming a post-treatment system and a fuel feed valve (17) for feeding fuel for post processing in the post-treatment system arranged inside it. When any catalyst has a degree of degradation exceeding a predetermined degree of degradation, the method of feeding the post-treatment fuel is reset so that the post-treatment fuel required for purification of the exhaust gas can be fed into the catalyst with the lowest degree of degradation to make the catalyst with the lowest degree of degradation handle the purification action of the exhaust gas.

Abstract: In an exhaust purification system of an internal combustion engine, comprising a NOX catalyst device, which can satisfactorily store NOX in the exhaust gas when the concentration of oxygen in the exhaust gas is high and can release the stored NOX and purify the released NOX to N2 by reducing materials in the exhaust gas when the concentration of oxygen is decreased as a regeneration treatment, the regeneration treatment is carried out to change a combustion air-fuel ratio from a lean air-fuel ratio to a set rich air-fuel ratio, and N2O reducing material is supplied to the NOX catalyst device during at least one of a first period set within a period in which an air-fuel ratio in the exhaust gas within said NOX catalyst device changes from the lean air-fuel ratio to the set rich air-fuel ratio when the regeneration treatment is started and a second period set within a period after an air-fuel ratio in the exhaust gas within the NOX catalyst device becomes the stoichiometric air-fuel ratio when the regeneration

Abstract: An exhaust purification system of an internal combustion engine arranging in an engine exhaust passage an NOx storing reducing catalyst storing NOx contained in exhaust gas when an air-fuel ratio of inflowing exhaust gas is lean and reducing and purifying stored NOx when the air-fuel ratio of the inflowing exhaust gas becomes a stoichiometric air-fuel ratio or rich, which system is provided with an NOx production reducing means for reducing an amount of production of NOx produced in a combustion chamber due to change of a combustion state of the engine and temporarily reduces the amount of production of NOx by the NOx production reducing means when an amount of N2O flowing out from the NOx storing reducing catalyst is anticipated to exceed an allowable amount.

Abstract: In an exhaust purification system of an internal combustion engine comprising an exhaust purification device which receives a bad influence from SOX in the exhaust gas and a S trap device arranged upstream of the exhaust purification device, which can store SOX in the exhaust gas, an amount of SOX passing through the S trap device is integrated as an integrated value, each allowance value of the integrated value for each elapsed period from the start time of the use of the S trap device is set, and when the current integrated value exceeds the corresponding allowance value and between a first set period ago and the current time, fuel has been supplied into the fuel tank and engine oil has not been exchanged, it is determined that fuel with a high concentration of sulfur has been supplied into the fuel tank.

Abstract: An exhaust purification apparatus of an internal combustion engine purifying exhaust gas by removing SOx from the exhaust gas is provided. In the exhaust purification apparatus provided with sulfur oxide trapping material for trapping sulfur oxides exhausted from an internal combustion engine, aggregates of the sulfur oxide trapping material (41) are arranged able to contact the exhaust gas in spaces (44) separated by partitions comprised of a porous material (42) having permeability.

Abstract: An internal combustion engine in which an SOx trap catalyst able to trap SOx contained in exhaust gas is arranged in an engine exhaust passage upstream of an NOx storing catalyst. The SOx trap catalyst is strengthened in basicity compared with the NOx storing catalyst to an extent so that when the temperature of the SOx trap catalyst is in the temperature range at the time of ordinary operation, that is, substantially 150° C. to substantially 400° C., the NOx purification rate by the SOx trap catalyst becomes less than substantially 10 percent of the NOx purification rate by the NOx storing catalyst. When NOx should be released from the NOx storing catalyst, the air-fuel ratio of the exhaust gas flowing into the SOx trap catalyst is temporarily switched from lean to rich.

Abstract: In an internal combustion engine, an SOX trap catalyst (13) which traps SOX contained in the exhaust gas is arranged upstream of an NOX storing catalyst (15) in an engine exhaust passage. When the NOX storing catalyst (15) should release NOX, auxiliary fuel is injected into a combustion chamber (2) at a combustible timing after the completion of injection of fuel into the combustion chamber (2) for generating the engine output. At this time, the auxiliary fuel is injected so that the air-fuel ratio A/F of the combustion gas in the combustion chamber (2) does not become below a minimum allowable air-fuel ratio M where SOX trapped at the SOX trap catalyst (13) will not be released.

Abstract: An internal combustion engine in an engine exhaust passage of which an NOx adsorption catalyst (12) adsorbing NOx contained in exhaust gas at the time of a low temperature and desorbing the adsorbed NOx when the temperature rises and an NOx storage catalyst (14) are arranged. When the NOx storage catalyst (14) can store NOx, the temperature of the NOx adsorption catalyst (12) is made to forcibly rise to a target temperature at which the amount of NOx which the NOx storage catalyst (14) can store is desorbed, and the NOx desorbed from the NOx adsorption catalyst (12) is stored in the NOx storage catalyst (14).

Abstract: In the present exhaust purification system of an internal combustion engine, a particulate filter is arranged downstream of an NOx storage/reduction catalyst device and an S trap device is arranged upstream of the NOx storage/reduction catalyst device. A first fuel supplying means for supplying additional fuel for regeneration of the particulate filter to the exhaust system upstream of the S trap device or into the cylinder is provided. An amount of the additional fuel supplied by the first fuel supplying means is controlled to make the S trap device not release SOx. A second fuel supplying means is provided in the exhaust system between the NOx storage/reduction catalyst device and the particulate filter to make up for a deficiency of the additional fuel supplied by the first fuel supplying means in the regeneration treatment of the particulate filter.

Abstract: An internal combustion engine wherein an SOx trap catalyst (12), an NOx storage catalyst (14), and a fuel addition valve (15) are arranged in an engine exhaust passage. When making the air-fuel ratio of the exhaust gas flowing into the NOx storage catalyst (14) the stoichiometric air-fuel ratio or rich so as to make the NOx storage catalyst (14) release NOx, additional fuel is supplied into the combustion chamber (2) and fuel is added from the fuel addition valve (15). At this time, the amount of additional fuel to the combustion chamber (2) is controlled so that the air-fuel ratio of the exhaust gas exhausted from the combustion chamber (2) becomes the smallest in the range where the SOx trap catalyst (12) does not release SOx.

Abstract: In an internal combustion engine, an NOx selective reducing catalyst is arranged inside an engine exhaust passage, an oxidation catalyst is arranged upstream of the NOx selective reducing catalyst, and an NOx adsorption catalyst is arranged upstream of the oxidation catalyst. The NOx adsorption catalyst has a property of releasing NOx when the temperature rises and a property of trapping the SOx contained in the exhaust gas. The inflow of SOx into the oxidation catalyst is suppressed by the NOx adsorption catalyst to prevent the NO released from the NOx adsorption catalyst being oxidized to NO2 at the oxidation catalyst from being obstructed by SOx.

Abstract: In an internal combustion engine, an SOx trap catalyst (11) able to trap SOx contained in exhaust gas is arranged in an engine exhaust passage upstream of an NOx storing catalyst (12). When whether the SOx trap catalyst (11) has deteriorated should be judged, the SOx trap catalyst (11) is raised in temperature in the state with the air-fuel ratio of the exhaust gas flowing into the SOx trap catalyst (11) maintained lean. At this time, the concentration of NOx released from the SOx trap catalyst (11) is detected by the NOx concentration sensor (24). When the NOx concentration is a set value or less, the catalyst is judged to have deteriorated.

Abstract: In an internal combustion engine, a metal or a metal compound (10) capable of capturing a sulfur component contained in an exhaust gas is provided in a flow path of the exhaust gas. When the amount of the sulfur content captured by the metal or the metal compound (10) is increased as the lapse of time, a physical property of the metal or the metal compound (10) which varies with increase in the amount of the captured sulfur component is measured. Based on the measurement value, the sulfur component in the gas can be detected.

Abstract: In an internal combustion engine, an NOx selective reduction catalyst (14) is arranged in an engine exhaust passage, and an NOx storage catalyst (12) is arranged in the engine exhaust passage upstream of the NOx selective reduction catalyst (14). When the amount of NOx stored in the NOx storage catalyst (12) exceeds a predetermined allowable value, the NOx storage catalyst (12) is raised in temperature to make the NOx storage catalyst (12) release the NOx. The amount of urea feed is decreased by exactly the amount of reduction of the calculated stored NOx amount with respect to the amount of urea feed determined from the engine operating state, and the amount of urea feed is increased by exactly the amount of reduction of the calculated released NOx amount with respect to the amount of urea feed determined from the engine operating state.

Abstract: A NOx storing catalyst (11) comprising a precious metal catalyst (46) and NOx absorbent (47) is arranged in an exhaust passage. When the air-fuel ratio of the exhaust gas is lean, the storing catalyst cold stores the NO2 contained in the exhaust in the absorbent when the catalyst is inactive and hot stores the cold stored NO2 in the absorbent when the catalyst is made active. The NO2 contained in the exhaust is cold stored in the absorbent when the catalyst is not activated, and when a predetermined NOx storing catalyst restoring condition (107) is met, a NOx storing catalyst restoring control (109, 115) including raising the NOx storing catalyst temperature to a predetermined temperature to active it (109) is executed so as to restore the cold storing capability of the NOx absorbent.

Abstract: An internal combustion engine wherein an NOx storing catalyst is arranged in an engine exhaust passage and an NOx selective reducing catalyst is arranged downstream of the NOx storing catalyst. Just before the air-fuel ratio of the exhaust gas flowing into the NOx storing catalyst is temporarily switched from lean to rich to release NOx from the NOx storing catalyst, an amount of NOx necessary for removing ammonia adsorbed on the NOx selective reducing catalyst is fed to the NOx selective reducing catalyst under a lean air-fuel ratio.