A TURBOCHARGER FOR AN INTERNAL COMBUSTION ENGINE

摘要

A turbocharger for an internal combustion engine comprising: a turbine driven by exhaust gas from the engine; a compressor for supplying compressed air to the engine, the compressor including an impeller driven by the turbine; an arrangement upstream of the impeller suitable for directing air such that it is swirling in a rotational sense on reaching the impeller; and control means arranged to control said arrangement such that as the speed of the impeller approaches a predetermined maximum speed limit the arrangement directs air such that it is swirling in the opposite rotational sense to that in which the impeller is being driven by the turbine.