Engine exhaust gas purification device

摘要

An exhaust gas purification device comprising a three way catalyst, an oxidizing catalyst and a NOx absorbent which are arranged in this order in the exhaust passage. A rich air-fuel mixture is burned in the combustion chamber, and the exhaust gas discharged from the engine is initially introduced into the three way catalyst. Secondary air is fed into the exhaust passage between the three way catalyst and the oxidizing catalyst so that the air-fuel ratio of the exhaust gas flowing into the oxidizing catalyst and the NOx absorbent becomes lean.