Patent ID: 6434928
Filing Date: 2002-08-20
Classification: B01D,B60K,B60L,B60W,F01N,F02D,Y02T,Y10S

Abstract:
An exhaust gas purifying system of an internal combustion engine, comprisinga generator driven by said internal combustion engine; a battery charged with an electricity generation output from said generator; and a NOx adsorption catalyst placed in an exhaust gas passage, which catalyst chemically sorbs NOx in a state where the amount of an oxidizer is larger than that of a reducer in the stoichiometry relation of oxidation reduction between components contained in exhaust gas exhausted from said internal combustion engine and which catalytically reduces the adsorbed or absorbed NOx in a state where the amount of the reducer is at least equivalent to that of the oxidizer, said system further comprising: a sulfur-poisoning estimation means for estimating sulfur-poisoning of the NOx adsorption catalyst at an operation time from operational parameters of said internal combustion engine; a sulfur-poisoning evaluation means for evaluating when an of sulfur absorption estimated value exceeds a predetermined value; an air-fuel mixture control means for controlling the combustion condition of said internal combustion engine to the stoichiometric air-fuel ratio or a rich air-fuel ratio in a predetermined time period when it is evaluated by said sulfur-poisoning evaluation means that the estimated value exceeds a predetermined value, means for increasing an air flow rate more than a present air flow rate; and an absorption means which makes said generator absorb the increased proportion of the internal combustion engine output generated while the combustion condition of said internal combustion engine is controlled to the stoichiometric air-fuel ratio or a rich air-fuel ratio by said air-fuel mixture control means.