Exhaust gas re-circulation device for turbo charged IC engines with exhaust return pipe and regulator unit to regulate pressure of returned exhaust gas to keep is above charging air pressure when required

摘要

The device incorporates a turbo charger (2) with double-flow exhaust turbine (8), compressor (1), and exhaust pipe (7a,b) and charging air pipe (5). A return pipe (16) connects the exhaust pipe in front of the turbine, to the charging air pipe after the compressor. The channels (9,10) of the double-flow turbine are formed and/or supplied with devices so that asymmetric throughput behavior can be set. The turbine has variable geometry for this purpose. A regulator unit (21) controls the pressure in the exhaust return pipe so that this can be set at a higher level than the pressure in the charging air pipe after the compressor.