Patent ID: RE42056

Claim:
A system for purifying exhaust gas generated by an internal combustion engine having an air intake system and an exhaust system which includes an exhaust pipe extending from an exhaust manifold of the engine and a catalyst installed in the exhaust pipe, the exhaust system exhausting gas generated by the engine to the atmosphere, including: a bypass branching out from the exhaust pipe at a location downstream of the catalyst and merging to the exhaust pipe downstream of the branching point; an adsorber installed in the bypass; a valve means which closes the bypass; a conduit connected to the bypass at one end and connected to the air intake system for recirculating the exhaust gas to the air intake system; valve control means which opens the valve means for a period since starting of the engine to introduce the exhaust gas to the bypass such that the adsorber installed in the bypass adsorbs the unburnt component in the exhaust gas; and an EGR control means which causes the exhaust gas introduced in the bypass to be recirculated to the air intake system through the conduit; wherein the improvement comprises: the valve means is provided at or close to the branching point in the exhaust pipe; and a chamber is provided close to the branching point such that the conduit is connected to the bypass at the one end in the chamber.