摘要 |
A power unit 10 for a vehicle comprises an i.c. engine 12, an air intake system 20, a turbocharger 22 having a compressor 24 driven by an exhaust turbine 26, and a storage tank 44 to store some of the air compressed by the compressor 24. In one embodiment, a mixing tank 52 is connected to the intake system 20 to receive some of the compressed air from the storage tank 44 and exhaust gas from the engine so as to mix the received air with the received exhaust gas. Alternatively, a component (64, fig.2) different from the engine, eg a pneumatic brake, alternator or cooling fan, can be driven by compressed air from the storage tank 44, eg by a shaft driven by a further turbine wheel. The storage tank 44 may be connected to the intake system 20 upstream of an intercooler 40. |