Abstract: An arrangement for supercharging an internal combustion engine such as a diesel engine wherein a turbo-charger incorporating a turbine driven by the exhaust gases from the engine is coupled to and drives a compressor which provides charging air for the engine at the desired pressure. A portion of the exhaust gases is recirculated through the engine by introducing it into the charging air in a part of the compressor at a point following the rotor blading which is at a lower pressure than the exhaust gases thus avoiding any deleterious corrosion effect upon the blading. The amount of the exhaust gases being so recirculated is controlled either by an open or closed type of control circuit.

Abstract: In a two-stage exhaust-gas turbocharger the shafts for each stage are disposed in laterally spaced, parallel relation. The exhaust-gas turbine of each stage is arranged within the same housing which can be a common housing or a twin housing with the housing parts joined together by flange connections. The bearing for the end of each shaft located adjacent the turbine is positioned within the housing while the bearing for the opposite end of the shaft associated with the compressor is positioned outside the housing.