Exhaust gas purifying device and exhaust gas purifying method in internal combustion engine

摘要

Catalysts are respectively provided in a plurality of parallel exhaust paths of an internal combustion engine. A flow rate adjusting section adjusts a flow rate of an exhaust gas discharged from a first exhaust path to a downstream side, and a flow rate of an exhaust gas supplied to an intake path from the first exhaust path via a first exhaust gas recirculating path. A control section controls the flow rate adjusting section in such a manner that a ratio of the flow rate of the exhaust gas discharged from the first exhaust path with respect to the flow rate of the exhaust gas discharged from the other exhaust paths than the first exhaust path becomes smaller in the case that a temperature of the catalyst exists in a preset low temperature region than in other cases. Accordingly, it is possible to achieve an early activation in at least one of a plurality of catalysts while avoiding an addition of mechanisms.