Patent ID: 8763393

Claim:
A method of assembling a turbocharger assembly, comprising the steps of: providing a turbine housing defining a chamber for receiving exhaust gas, and an axially extending bore through which exhaust gas is discharged from the turbine housing, the bore being stepped such that the bore has a first inside diameter for a predetermined distance from an upstream end of the bore axially toward an opposite downstream end of the bore, and the bore then is abruptly reduced to a smaller second inside diameter so as to define a step having an axially upstream-facing step surface; disposing a sealing ring within the bore against the step surface, the sealing ring comprising a generally annular body having a generally U- or V-shaped cross-section oriented such that an open side of the U- or V-shaped cross-section faces in a radial direction, the U- or V-shaped cross-section defining opposing first and second legs, the first leg being engaged against the step surface of the bore and the second leg facing the upstream end of the bore, the sealing ring being resiliently deformable under axial compression; providing a variable-nozzle assembly comprising an insert having a tubular portion sized to be received into the bore of the turbine housing and having a nozzle portion extending generally radially out from one end of the tubular portion, the variable-nozzle assembly further comprising a generally annular nozzle ring axially spaced from the nozzle portion and an array of vanes circumferentially spaced about the nozzle ring and rotatably mounted to the nozzle ring such that the vanes are variable in setting angle for regulating exhaust gas flow; inserting the tubular portion of the insert into the bore until an end face of the tubular portion contacts the second leg of the sealing ring; fastening a center housing assembly to the turbine housing so as to capture the variable-nozzle assembly therebetween in such a manner that the sealing ring is axially compressed between the end face of the tubular portion of the insert and the step surface of the bore; disposing a heat shield between the nozzle ring and the center housing such that the heat shield is compressed therebetween and such that the heat shield and the sealing ring exert axially oppositely directed biasing forces on the variable-nozzle assembly, wherein the heat shield comprises a sheet metal part that is generally annular and has a radially outer portion engaged against an axially upstream-facing surface of the nozzle ring and a radially inner portion engaged against an axially downstream-facing surface of the center housing; and providing a retainer ring having a radially outer portion engaged against an axially downstream-facing surface of the center housing and a radially inner portion engaged against an axially downstream-facing surface of the nozzle ring, the retainer ring urging the nozzle ring against the biasing force exerted by the heat shield.