Patent ID: 7722336

Claim:
An assembly comprising: an operational shaft of a turbocharger that comprises a joint wherein the joint comprises a pilot surface; a unitary compressor wheel that comprises a proximate end; a distal end; an axis of rotation; a z-plane positioned between the proximate end and the distal end; and a proximate end extension wherein the extension comprises a thrust collar pilot diameter, a joint pilot diameter and an engagement mechanism disposed between the thrust collar pilot diameter and the joint pilot diameter, the joint pilot diameter configured for alignment with the pilot surface of the joint and the engagement mechanism configured for engagement with the joint; and a thrust collar, disposed between the compressor wheel and the shaft, that comprises a pilot surface configured for alignment with the thrust collar pilot diameter of the extension; wherein the assembly comprises an axial dimension Δz max measured from the z-plane to a tip of the extension, an axial dimension Δz S measured from the z-plane to an end of the shaft, and an axial dimension Δz C measured from the z-plane to a compressor wheel side annular face of the thrust collar, wherein Δz C <Δz S <Δz max , wherein the difference between Δz C and Δz S is determined by an axial thickness of the thrust collar and wherein the thrust collar pilot diameter is disposed between the axial dimensions Δz C and Δz S and is larger than the joint pilot diameter.