Centrifugal compressor, turbocharger provided with the centrifugal compressor, and method for producing the centrifugal compressor

Abstract

An object is to provide a centrifugal compressor in which an axial force applied from a shrink-fit impeller to a sleeve section is ensured even if the sleeve section is separated from a clamp surface in an axial direction of an attachment hole, as well as a turbocharger provided with the centrifugal compressor and a method of producing the centrifugal compressor. An inner peripheral surface of an attachment hole formed on a hub includes a clamp surface and a diameter-widening surface, and an outer peripheral surface of a sleeve section includes a diameter-reducing surface. The diameter-widening surface and the diameter-reducing surface respectively include an impeller-side contacting portion and a sleeve-side contacting portion which contact each other, and a relationship represented by an expression θs<atan (d/L) is satisfied, where d is a length from an axis of the attachment hole to the sleeve-side contacting portion in a radial direction of the attachment hole, L is a length from the sleeve-side contacting portion to the clamp surface in the axial direction of the attachment hole, and θs is a sleeve inclination angle formed by an intersection of an axis of the sleeve section and a generatrix of a virtual cone which contacts the diameter-reducing surface at the sleeve-side contacting portion.