EXHAUST EMISSION CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINE

PROBLEM TO BE SOLVED: To provide an exhaust emission control device for an internal combustion engine suppressing accumulation of urea-derived deposit onto a tip of a urea water injector, without increasing a manufacturing cost caused by complicated structure. SOLUTION: A connection pipe 22 penetrates from one side face of a casing 17 to the other side face thereof, and a lot of holes 22a are formed to an exposed part of the connection pipe 22 in the casing 17. An injection nozzle 27 is inserted from the other side face of the casing 17 into the connection pipe 22, exhaust gas guided from the internal combustion engine into the casing 17 is guided into the connection pipe 22 through each holes 22a, the urea water injected from the injection nozzle 27 is mixed into the exhaust gas and is guided to a downstream NOx catalyst through the connection pipe 22. A ratio L/D between a projection length L of the injection nozzle 27 into the connection pipe 22 and an inner diameter D of the casing is set to be within 0.3-1.0. COPYRIGHT: (C)2010,JPO&INPIT