Fluid-supported thrust bearings

An apparatus, comprising:

• a first structure;
• a second structure rotatably coupled to the first structure, wherein the second structure is adapted to rotate relative to the first structure about an axis of rotation;
• a thrust bearing axially disposed between the first structure and the second structure, wherein the thrust bearing comprises:
• a plurality of circumferentially-spaced roller elements disposed about the axis of rotation;
• and
• a first bearing race in contact with the plurality of roller elements;
• a first fluid cavity axially disposed between the first structure and the first bearing race;
• and
• a fluid in the first fluid cavity configured to transfer axial loads between the first structure and the first bearing race.

A method for supporting an axial load between a first structure and a second structure and allowing the first structure to rotate relative to the second structure about an axis of rotation, the method comprising:

• (a) placing a thrust bearing axially between the first structure and the second structure, wherein the thrust bearing comprises:
• a first annular bearing race axially adjacent the first structure;
• a second annular bearing race axially adjacent the second structure;
• a plurality of circumferentially spaced roller elements axially disposed between the first bearing race and the second bearing race, wherein the roller elements contact the first bearing race and the second bearing race;
• (b) forming an annular fluid cavity axially between the first bearing race and the first structure;
• (c) filling the fluid cavity with a fluid;
• and
• (d) transferring the axial load between the first bearing race and the first structure through the fluid in the fluid cavity.