Variable geometry vane assembly for a turbocharger

摘要

A variable-vane assembly for a variable nozzle turbine comprises a nozzle ring (20) supporting a plurality of vanes (40) affixed to vane arms (44) that are engaged in recesses in the inner edge of a unison ring (30). The unison ring (30) is rotatable about the axis of the nozzle ring (20) so as to pivot the vane arms (40), thereby pivoting the vanes in unison. A plurality of guide pins (22) for the unison ring are inserted into apertures (24) in the nozzle ring (20) and are rigidly affixed therein such that the guide pins are non-rotatably secured to the nozzle ring with a guide portion (25) of each guide pin projecting axially from the face of the nozzle ring. Each guide portion (25) defines a shoulder (26) radially overlapping the inner edge of the unison ring (30) such that the unison ring is restrained by the guide pins (22) against excessive movement in both radial and axial directions.