Patent ID: 6546721
Filing Date: 2003-04-15
Classification: F01N,Y02A

Abstract:
An exhaust gas purification device of an engine having a combustion chamber comprising an exhaust passage and a particulate filter arranged in said exhaust passage for removing particulate in exhaust gas exhausted from said combustion chamber; said particulate filter being a particulate filter having a function of removing, by oxidation, particulate in the exhaust gas without emitting a luminous flame when an amount of discharged particulate discharged from the combustion chamber per unit time is smaller than an amount of particulate removable by oxidation per unit time without emitting a luminous flame on the particulate filter and of absorbing NOx in exhaust gas when an air-fuel ratio of the exhaust gas flowing into the particulate filter is lean and releasing the absorbed NOx when the air-fuel ratio of the exhaust gas flowing into the particulate filter becomes the stoichiometric air-fuel ratio or rich; the amount of said discharged particulate and the temperature of the particulate filter being maintained in most operating states within a simultaneous particulate and NOx treatment region in a temperature region wherein the amount of discharged particulate becomes smaller than an amount of particulate removable by oxidation and a NOx absorption rate becomes more than a certain value at all times.