Patent ID: 6978605

Claim:
An exhaust emission control system for an engine, comprising an exhaust emission control catalyst disposed in an exhaust muffler whose inside is divided into a plurality of chambers, wherein at least a portion of the inside of the exhaust muffler is divided into: a first chamber as one of a plurality of chambers, the first chamber converting mainly NOx in exhaust gas; a second chamber as another of the plurality of chambers, the second chamber converting HC and CO in the exhaust gas, and a partition wall disposed between the first and second chambers and having a conduit for guiding the exhaust gas from the first chamber to the second chamber, and wherein the exhaust muffler comprises: an exhaust gas inlet for introducing the exhaust gas into the first chamber; an external-air suction means provided in the partition wall for sucking external air into the second chamber; and a discharge pipe for discharging the external air and the exhaust gas flowing through the second chamber.