It is an object of the present invention to dissolve a problem that an uncomfortable feeling is given to an operator due to a shock and a change of an engine sound caused by a fluctuation of an engine torque, at the time of renewal of an exhaust gas purifi...

A nitrogen oxide reducing system (100) of a diesel engine (1, 110) can reduce nitrogen oxide contained in an exhaust gas of the diesel engine and whereby cab adapt to a restriction. At a tip end of a mixer (3, 120), air holes required by the engine (1, 110...