Disengageable axial thrust bearing with internal preload

Abstract

In a disengageable axial thrust bearing for a rotary machine, an outer ring has first and second outer half-rings (A,B) centered in a casing () and clamped in the axial direction between a stationary thrust member () and a first pre-loading system () exerting a first predetermined axial force such that, so long as the axial load exerted on the axial thrust bearing via a synchronization element () is greater than a determined threshold value, rolling elements () with oblique contacts present respective single lines () having two points of contact (A,B) with an inner ring () and with the first outer half-ring (A), the second outer half-ring (B) being spaced apart from the first by a second predetermined axial force exerted by a second pre-loading system () inserted in the axial direction between the first and second outer half-rings, and such that the inner ring () is driven in rotation by the synchronization element, whereas, when the axial load exerted on the axial thrust bearing becomes less than this determined threshold value, a second line () having two additional points of contact (A,B) is created between each of the oblique-contact rolling elements () and the inner ring () and the second outer half-ring (B) such that the axial thrust bearing is disengaged.