Patent ID: 9695871
Date: 2017-07-04
CPC Classifications: F16C,H02K

Claim:
1. An assembly comprising: a rotating shaft supported with respect to a stationary housing by at least one active magnetic bearing presenting a mean radial air gap and at least one auxiliary bearing having a first smooth surface integral with the housing and a second smooth surface integral with the rotating shaft, wherein the first and second smooth surfaces are opposite to each other and define a clearance which is less than the mean radial air gap, and wherein the first smooth surface and the second smooth surface each exhibit symmetry around a longitudinal axis of the rotating shaft and have different profiles in a longitudinal cross-section including the longitudinal axis, wherein the second smooth surface comprises a heat-treated surface formed on a sleeve fixedly mounted on the rotating shaft, wherein the sleeve comprises a profile with a radius defined by reduction delta H given by equation: wherein h is a total drop at an end of the profile, wherein u is a distance of a point from a center of the sleeve, wherein lc is a total length of a section of the sleeve to which no modification is done, wherein la is a total length of the section of the sleeve, and wherein exp is an exponent larger than 1.