Abstract: A method of assembling a turbocharger having a vaned turbine nozzle includes first forming a sub-assembly of a center housing, shaft, bearings, compressor wheel, turbine wheel, and vane assembly. The vane assembly is held captive in attachment to the center housing by an annular heat shield that includes prongs or the like at its inner and outer peripheries for respectively engaging a first catch formed on the center housing and a second catch formed on the nozzle ring of the vane assembly. The heat shield forms a snap fit to the center housing and nozzle ring, thereby connecting the cartridge to the center housing. The whole sub-assembly is then joined to the turbine housing, in the process axially compressing the heat shield and a spring shroud for exerting an axial biasing force on the nozzle ring.

Abstract: A method of assembling a turbocharger having a vaned turbine nozzle includes first forming a sub-assembly of a center housing, shaft, bearings, compressor wheel, turbine wheel, and vane assembly. The vane assembly is held captive in attachment to the center housing by an annular heat shield that includes prongs or the like at its inner and outer peripheries for respectively engaging a first catch formed on the center housing and a second catch formed on the nozzle ring of the vane assembly. The heat shield forms a snap fit to the center housing and nozzle ring, thereby connecting the cartridge to the center housing. The whole sub-assembly is then joined to the turbine housing, in the process axially compressing the heat shield and a spring shroud for exerting an axial biasing force on the nozzle ring.

Abstract: A turbocharger can include a center housing; a bearing disposed in a through bore of the center housing where the through bore of the center housing defines a longitudinal axis; a shaft rotatably supported by the bearing; a compressor wheel operatively coupled to the shaft; a turbine wheel operatively coupled to the shaft; and a turbine housing assembly operatively coupled to the center housing where the turbine housing assembly includes: a turbine housing; and a cartridge that includes a nozzle wall component and a plate component that are spaced axially by spacers, where the nozzle wall component includes spacer bores for the spacers and where the nozzle wall component has a non-circular outer perimeter defined at least in part by arcs where adjacent arcs intersect at intersection points, and where each of the intersection points is radially outwardly from a respective one of the spacer bores.