Patent ID: 7140849

Claim:
A variable geometry turbocharger comprising: a turbine wheel mounted within a turbine housing on one end of a turbocharger shaft for rotation about a turbocharger axis, the turbine housing defining an annular turbine inlet around the turbine wheel; a compressor wheel mounted within a compressor housing on the other end of said turbocharger shaft for rotation with the turbine wheel about said axis; turbocharger shaft bearing assemblies located within a bearing housing connected between the turbine housing and the compressor housing; a variable geometry mechanism for varying the size of the annular turbine inlet; and an electric motor for actuating the variable geometry mechanism; wherein the electric motor is a tubular linear electric motor comprising a fixed annular stator ring and an axially moveable annular forcer ring, arranged coaxially about said turbocharger axis with movement of the forcer ring effecting adjustment of the variable geometry mechanism.