To provide an exhaust emission control system of an internal combustion engine which can make a flow of an exhaust gas to an exhaust gas aftertreating unit with a simple constitution uniform and which can improve a function of the exhaust gas aftertreating unit.
The exhaust emission control system 1 of the internal combustion engine is provided in an exhaust passage of the internal combustion engine and includes the exhaust gas aftertreating unit 10, a case 20 containing the exhaust gas aftertreating unit 10, an upstream chamber 24 provided at an upstream of the exhaust gas aftertreating unit 10 in the case 20, an inlet tube 26 provided in this upstream chamber 24 so that the exhaust gas flows in the upstream chamber 24 to close a downstream end of the flowing direction of the exhaust gas and having many pores 26A on an outer periphery, and an internal radially enlarged tube 30 provided at coaxial center on the mid-way position of a longitudinal direction of the inlet tube 26 to enlarge to the downstream side of the flowing direction.
KOSHIMIZU KENGO
Kanji Nakayama
Tsuyoshi Ishizaki