EXHAUST EXMISSION CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To prevent a reducing agent added to an exhaust port for cleaning NOx from reaching to an intake system through an EGR device. SOLUTION: A NOx catalyst 17 is mounted on the way of an exhaust pipe. An intake manifold 2 and an exhaust manifold 14 are connected by an EGR pipe 23 for allowing a part of the exhaust to be recirculated to an intake system. A fuel addition nozzle 19 for adding the fuel into an exhaust gas is mounted oppositely to an exhaust port 13 of a fourth cylinder to clean NOx by the NOx catalyst 17, and its fuel injecting direction is directed to a connecting part with an exhaust cooling pipe 16 in the exhaust manifold 14. A connecting part with the EGR pipe 23 is located near a first cylinder in the exhaust manifold.