A thrust bearing assembly includes an upper thrust bearing and a lower thrust bearing for use in an engine assembly of a vehicle and which, are preferably, identically configured. The upper and lower thrust bearings each include an arcuate bearing shell with a concave inner surface and a convex outer surface and each may be formed with a pair of axially spaced flanges extending radially outwardly of the bearing shells. The flanges may be formed as one piece with the bearing shell and the thickness of one of the flanges is greater than that of the other of the flanges. The thicker flanges are load bearing and preferably contoured, whereas the thinner flanges are not. The bearings are installed with the thick flange of each bearing matched radially opposite the thin flange of the companion bearing to minimize fatigue and failure normally attributed to repeated seating and unseating of the bearing assemblies having flanges of equal thickness caused by changing bending loads imparted by a shaft.
1. A thrust bearing assembly, comprising:
an upper thrust bearing including an arcuate shell with a concave inner surface and a convex outer surface extending arcuately between first and second ends and extending axially between opposite edges;
a lower thrust bearing including an arcuate bearing shell with a concave inner surface and a convex outer surface extending arcuately between first and second ends and extending axially between opposite edges;
said upper thrust bearing including a first flange extending radially from said outer surface of said upper thrust bearing adjacent one of said edges and presenting an axially outer thrust face spaced axially outwardly from an axially outer most surface of said lower thrust bearing; and
said lower thrust bearing including a first flange extending radially from said outer surface of said lower thrust bearing adjacent one of said edges of said lower thrust bearing on a side axially opposite to that of said flange of said upper thrust bearing, and presenting an axially outer thrust face spaced axially outward from an axially outer most surface of said upper thrust bearing.
2. The thrust bearing assembly of claim 1 wherein said upper thrust bearing further comprising:
a second flange extending radially from said outer surface of said upper thrust bearing adjacent to the other of said edges and thinner than said first flange of said upper thrust bearing.
3. The thrust bearing assembly of claim 2 wherein said lower thrust bearing further comprising:
a second flange extending radially from said outer surface of said lower thrust bearing adjacent to the other of said edges and thinner than said first flange of said lower thrust bearing.
4. The thrust bearing assembly of claim 3 wherein each of said first flanges are formed as one piece with said respective bearing shells of said upper and said lower thrust bearings.
5. The thrust bearing assembly of claim 4 wherein each of said second flanges are formed as one piece with said respective bearing shells of said upper and said lower thrust bearings.
6. The thrust bearing assembly of claim 5 wherein said first and said second ends of said upper and said lower thrust bearing are substantially in mating contact.
7. The thrust bearing assembly of claim 1 wherein each of said first flanges has an outer face and at least one of said outer faces is contoured.
8. The thrust bearing assembly of claim 1 wherein each of said first flanges has an outer face and at least one of said outer faces defines at least one oil groove.
9. The thrust bearing assembly of claim 1 wherein each of said first flanges has an outer face and said thrust bearing assembly further comprises a bearing material disposed on at least one of said outer faces.
10. The thrust bearing assembly of claim 9 wherein said bearing material is disposed on both of said outer faces of said first flanges.
11. An engine assembly for use in a vehicle, said assembly comprising:
an upper support surface;
a shaft received within said upper support surface; and
a thrust bearing assembly rotatably supporting said shaft and having:
an upper thrust bearing disposed between said upper support surface and said shaft and including an arcuate shell with a concave inner surface and a convex outer surface extending arcuately between first and second ends and extending axially between opposite edges;
a lower thrust bearing including an arcuate bearing shell with a concave inner surface and a convex outer surface extending arcuately between first and second ends and extending axially between opposite edges;
said upper thrust bearing including a first flange extending radially from said outer surface of said upper thrust bearing adjacent one of said edges and presenting an axially outer thrust face spaced axially outwardly from an axially outer most surface of said lower thrust bearing and said upper thrust bearing also including a second flange extending radially from said outer surface of said upper thrust bearing adjacent to the other of said edges and thinner than said first flange of said upper thrust bearing; and
said lower thrust bearing including a first flange extending radially from said outer surface of said lower thrust bearing adjacent one of said edges of said lower thrust bearing on a side axially opposite to that of said flange of said upper thrust bearing, and presenting an axially outer thrust face spaced axially outward from an axially outer most surface of said upper thrust bearing and said lower thrust bearing also including a second flange extending radially from said outer surface of said lower thrust bearing adjacent to the other of said edges and thinner than said first flange of said lower thrust bearing.
12. The engine assembly of claim 11 further comprising:
a shaft encircled by said upper and lower thrust bearings and having first and second lobes disposed on opposite axial sides of said upper and lower thrust bearings, wherein said first flange of said upper thrust bearing engages said first lobe of said shaft and wherein said first flange of said lower thrust bearing engages said second lobe of said shaft.
13. The engine assembly of claim 12 wherein a first clearance distance is defined between said second flange of said upper thrust bearing and said upper support surface when said first flange of said upper thrust bearing abuts said upper support surface.
14. The engine assembly of claim 13 wherein said first flange of said upper thrust bearing is further defined as having a thickness greater than a sum of a thickness of said second flange of said upper thrust bearing and said first clearance distance.
15. The engine assembly of claim 14 further comprising:
a lower support surface, wherein said lower thrust bearing is disposed between said lower support surface and said shaft.
16. The engine assembly of claim 15 wherein a second clearance distance is defined between said second flange of said lower thrust bearing and said lower support surface when said first flange of said lower thrust bearing abuts said lower support surface.
17. The engine assembly of claim 16 wherein said first flange of said lower thrust bearing is further defined as having a thickness greater than a sum of a thickness of said second flange of said lower thrust bearing and said second clearance distance.
18. The engine assembly of claim 17 wherein said upper support surface is further defined as an engine block.
19. The engine assembly of claim 17 wherein said lower support surface is further defined as a bearing cap.
20. The engine assembly of claim 17 wherein said shaft is further defined as a crankshaft.