Patent ID: 7159393

Claim:
A device for purifying exhaust gases from a combustion engine ( 1 ), comprising a first filter ( 10 ) arranged in an exhaust conduit ( 7 ) between the engine ( 1 ) and an exhaust outlet ( 8 ) for removing particulate constituents from the exhaust gases, a recirculation conduit ( 11 ) branching off the exhaust conduit ( 7 ) downstream of the first filter ( 10 ) and upstream of the exhaust outlet ( 8 ) for diverting a part of the exhaust gases that have passed through said first filter ( 10 ) and recirculating this part of the exhaust gases to the air intake ( 2 ) of the engine ( 1 ), a second filter ( 30 ) arranged downstream of an inlet end ( 12 ) of the recirculation conduit ( 11 ) from the exhaust gas conduit ( 7 ) and between the inlet end ( 12 ) and air intake ( 2 ) of the engine ( 1 ), and having a lower nominal filtering grade than said first filter ( 10 ), and said exhaust conduit ( 7 ), recirculation conduit ( 11 ) and first and second filters ( 10 , 30 ) arranged such that gas flow occurs in only one direction through said exhaust conduit ( 7 ) and first filter ( 10 ), and then through said recirculation conduit ( 11 ) and second filter ( 30 ).