EXHAUST EMISSION CONTROL DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an exhaust emission control device designed to suppress erroneous detection of clogging of an injection nozzle.

SOLUTION: The exhaust emission control device for an engine is disposed in the exhaust system of the engine 1, and is equipped with: a reduction catalyst 4 reducing and purifying nitrogen oxide in exhaust gas by using urea water; a urea water tank 6 storing the urea water; a urea water supply means 7 that sucks the urea water from the urea water tank 6, mixes it with high pressure air and delivers the mixture; and the injection nozzle 5 injecting the urea water mixed with high pressure air into an exhaust pipe 3 in the exhaust system, upstream of the reduction catalyst 4 in exhaust flow. A clogging detection means 8 is also provided that detects the clogging of the injection nozzle based on the detection outputs of the pressure of air introduced into the urea water supply means 7 and the temperature of the injection nozzle 5.

COPYRIGHT: (C)2006,JPO&NCIPI