US Patent 7104060 Exhaust energy recovery system for combustion engine

An exhaust energy recovery system for a combustion engine having an exhaust passage has a displacement expansion device and a generator. The expansion device is located in the exhaust passage. Exhaust gas is introduced into the expansion device. The expansion device has an expansion chamber the volume of which varies in accordance with the pressure of exhaust gas and generates power in accordance with the volume variation of the expansion chamber. The generator generates electricity in accordance with the power generated by the expansion device. This efficiently recovers exhaust gas and effectively uses the recovered exhaust gas.