EXHAUST EMISSION CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To prevent deterioration in exhaust emission control due to the foreign matter in the exhaust gas reaching the constituents of the electric heat catalytic converter, by providing a current carrying heater upstream the catalytic converter installed in the exhaust system of the internal combustion engine, and by providing a foreign matter removal film upstream the current carrying heater. SOLUTION: In this exhaust emission control device, an exhaust pipe 101, a main catalytic converter unit 102, and a sub catalytic converter unit 103 are arranged in due order, and an electric heat catalytic converter(EHC) unit 104 is provided at the direct upstream of the sub catalytic converter unit 103. A foreign matter removal filter 5 is installed at the upstream of the EHC unit 104. The foreign matter removal filter 5 avoids adhesion of foreign matters to the EHC unit 104, and prevents the foreign matters in the exhaust gas from reaching the constituents of the EHC unit 104 leading to deterioration of the exhaust gas control characteristics. In this case, it is preferable that the foreign matter removal filter 5 be arranged within the exhaust gas passage in the vicinity of the EHC unit 104 and far from the exhaust port of a cylinder head of the internal combustion engine.