Patent ID: 6370869
Filing Date: 2002-04-16
Classification: F01N,F02B,F02D,F02F,F02M,Y02T

Abstract:
An exhaust purification device of an engine having an exhaust passage, comprising:a first catalyst arranged in the exhaust passage; a second catalyst arranged in the exhaust passage downstream of the first catalyst; judging means for judging if the engine is in an operating state where reducing components in an exhaust gas should mainly be made to oxidize by the first catalyst or if the engine is in an operating state where reducing components in the exhaust gas should mainly be made to oxidize by the second catalyst; and oxidation ratio controlling means for making a ratio of oxidation of reducing components in the exhaust gas at the first catalyst increase when it is judged that the engine is in an operating state where reducing components in the exhaust gas should mainly be made to oxidize by the first catalyst and for making the ratio of oxidation of reducing components in the exhaust gas at the first catalyst decrease when it is judged that the engine is in an operating state where reducing components in the exhaust gas should mainly be made to oxidize by the second catalyst; said judging means judging that the engine is operating in a state where the reducing components in the exhaust gas should mainly be made to oxidize by the first catalyst until when the second catalyst is activated after the engine is started.