A variable inlet area turbine.

摘要

The turbine which can drive an impeller wheel of a compressor of a turbocharger supplying air to an internal combustion engine of a motor vehicle is driven by exhaust gas from the engine supplied to an inlet volute (44) in a turbine housing (40) forming a first side (46) of a radial inlet passage (45) conveying the exhaust gas to a radial inward flow turbine wheel (18) on a shaft (16) rotating in a bearing housing (12). The other or second side of the inlet passage is formed by a wall (48) carrying an annular array of vanes (54) extending towards the side (46) but not secured thereto. This allows the turbine housing (40) to be rotated about the axis of the turbine wheel relatively to the housing (12) and vanes (54), to move an exhaust gas inlet to the volute (40) to any desired angular position about the turbine axis before the turbine housing is unlockably fastened to the bearing housing (12). The inlet area of the inlet passage (45) can be varied to any desired extent between a maximum and zero by an axially movable control ring (56) formed with axial slots accommodating the vanes (54). These slots are closed at their radially inner ends (72) but are open at an end (57) of the control ring facing the first side (46) of the inlet passage and are open at the outer periphery of the control ring (56) so that a substantial radially outward part of each vane extends beyond the periphery of the control ring. An inner surface (74) of the control ring (56) is in gas tight sliding contact with a stationary sealing ring (76).