Patent ID: 7430855

Claim:
A muffling apparatus having an exhaust emission purifying function, the apparatus being formed with a turning portion in an inside of a flow passage of an exhaust gas, and comprising at least: an injection nozzle, disposed in the flow passage of the exhaust gas on an upstream side of the turning portion, for injection-supplying a liquid reducing agent; and a reduction catalytic converter, disposed in the flow passage of the exhaust gas on a downstream side of the turning portion, for reductively purifying nitrogen oxides with the liquid reducing agent, and a diffusing member for generating a vortex flow of gas traveling in a vertical plane of the turning portion to cause diffusion of the liquid reducing agent into the exhaust gas flow, the diffusing member including a ring member on which a plurality of opening portions are formed, the opening portions arranged on a side of the ring member and disposed substantially in parallel with a flow direction of the exhaust gas entering into the turning portion from the flow passage of the exhaust gas on the upstream side of the turning portion, wherein the exhaust gas entering into the turning portion is injected in outward directions via the opening portions to thereby generate the vortex flow.