EXHAUST EMISSION CONTROL DEVICE

摘要

An exhaust emission control device capable of efficiently regenerate an NOx storage/reduction type catalyst storing NOx by post-injecting sufficient amount of a fuel without diluting an engine oil on the inner wall surface of a cylinder. An NOx absorber and an activated metal are carried on the NOx storage/reduction type catalyst (16) installed in the exhaust passage (14) of an engine (11), and a fuel adding means (17) adds the fuel into an exhaust gas inside the exhaust passage (14) to supply the fuel to the NOx storage/reduction type catalyst (16). The fuel adding means (17) is an accumulator fuel injection device post-injecting the fuel after a main injection to the cylinder (22) of the engine (11) at such a timing that the fuel is not ignited in the cylinder (22). The post-injection by the accumulator fuel injection device (17) is performed in three to twenty times in the latter period of the expansion stroke of the engine (11).