Patent ID: 8905640

Claim:
A thrust ring for an undercarriage in a track-type machine comprising: an annular body including an outer circular edge and an inner circular edge defining a common center axis, the annular body further including a first thrust surface on a first axial side of the annular body and a second thrust surface on a second axial side of the annular body; the first thrust surface having a first set of oil grooves formed therein at spaced apart locations about the center axis, and a first set of thrust faces positioned in an alternating arrangement with the first set of oil grooves; and the second thrust surface having a second set of oil grooves formed therein and positioned at spaced apart locations about the center axis which are offset from locations of the first set of oil grooves, and a second set of thrust faces positioned in an alternating arrangement with the second set of oil grooves; wherein each of the oil grooves extends from the inner circular edge to the outer circular edge and defines a throat area for supplying lubricating oil to the thrust faces on the corresponding axial side of the annular body, and each of the thrust faces extends from the inner circular edge to the outer circular edge and defines a face loading area for reacting face loads through the thrust ring; and wherein each of the oil grooves further includes a first lip surface and a second lip surface adjoining a first adjacent thrust face and a second adjacent thrust face, respectively, each of the first lip surface and the second lip surface defining a convex radius of curvature; a first transition surface and a second transition surface adjoining the first lip surface and the second lip surface, respectively, each of the first transition surface and the second transition surface defining a first concave radius of curvature which is less than the convex radius of curvature; and a basal surface adjoining each of the first transition surface and the second transition surface, the basal surface defining a second concave radius of curvature which is greater than the first concave radius of curvature and greater than the convex radius of curvature.