Patent ID: 8196394

Claim:
An exhaust purification apparatus for an engine, having a particulate filter that traps particulates contained in engine exhaust gas and an ammonia selective reduction-type NOx catalyst that selectively reduces NOx contained in the exhaust gas by using ammonia as a reducing agent, the apparatus comprising: an upstream casing that has a cylindrical shape and accommodates the particulate filter; an exhaust gas outlet that is formed in a side wall of the upstream casing so as to be located downstream from the particulate filter, and discharges the exhaust gas that has passed through the particulate filter; a urea-water injector that is fixed to the upstream casing to be located in a position opposed to the exhaust gas outlet, and injects urea-water toward the exhaust gas outlet; and a downstream casing that accommodates the ammonia selective reduction-type NOx catalyst into which the exhaust gas discharged from the exhaust gas outlet flows, wherein the side wall of the upstream casing has a recess depressed inward from the upstream casing and formed in a position opposed to the exhaust gas outlet; and the urea-water injector is fixed to the recess.