Aircraft wheel bearing arrangement
A bearing arrangement for an aircraft landing gear wheel is provided that effectively supports the wheel on an axle while maximizing internal wheel volume available for mounting a non-engine drive motor used to power the wheel and/or brakes or other structures within the maximized wheel volume. The bearing arrangement is preferably employed with a two-part aircraft wheel mounted on a landing gear axle and includes bearing structures located only on wheel sections adjacent to the axle. A specifically configured cantilevered joint portion of inboard and outboard wheel sections supports weight and loads bearing structures, eliminating the need for and space required by a high speed bearing. Stiffness necessary for strength and structural integrity is provided by the materials selected to form the wheel sections.
1. A bearing arrangement for an aircraft landing gear wheel that eliminates the need for a high speed bearing and increases landing gear wheel internal volume and landing gear wheel structural integrity, comprising:
a. an aircraft landing gear wheel comprising an inboard wheel section and an outboard wheel section extending axially along an aircraft landing gear wheel axle and radially between the axle and a tire mounted on the landing gear wheel;
b. a landing gear wheel internal volume formed within said inboard wheel section extending axially adjacent to the axle and radially between the axle and the tire to form a joint between an outer axial portion of said outboard wheel section adjacent to the tire and said outboard wheel section extending from said outer axial portion radially between the tire and the axle and axially adjacent to the axle, wherein a connection between an inboard wheel section axial portion adjacent to the axle and an outboard wheel section axial portion adjacent to the axle comprises a cantilevered joint; and
c. a pair of spaced bearing elements supporting the inboard and outboard wheel sections on the axle, wherein one of said bearing elements is positioned within said cantilevered joint in bearing contact between said inboard wheel section axial portion and said outboard wheel section axial portion and the other of said bearing elements is positioned in bearing contact between said outboard wheel section axial portion and the axle.
2. The bearing arrangement of claim 1 , wherein said cantilevered joint comprises an axial extension of said inboard wheel section axial portion in cantilevered relationship to an axial extension of said outboard wheel section axial portion adjacent to the axle, and each of said axial extensions is configured to receive said one bearing element, wherein said one bearing element is positioned in weight bearing relationship within said cantilevered joint between each of said axial extensions.
3. The bearing arrangement of claim 2 , wherein said cantilevered joint comprises a fastener element removably connecting said axial extension of said inboard wheel section axial portion with said outboard wheel section axial portion.
4. The bearing arrangement of claim 2 , wherein said cantilevered joint and said pair of bearing elements are configured to absorb loads transferred to said landing gear wheel.
5. The bearing arrangement of claim 1 , wherein each one of said pair of bearing elements comprises a roller bearing and bushings.
6. The bearing arrangement of claim 1 , wherein said outboard wheel section is formed of a material selected to provide stiffness to said wheel structure.
7. The bearing arrangement of claim 6 , wherein said outboard wheel section material comprises an alloy of steel or an alloy of titanium.
8. The bearing arrangement of claim 7 , wherein said alloy of steel comprises a nickel-cobalt-steel alloy and said alloy of titanium comprises a beta titanium alloy or an alpha-beta titanium alloy.
9. The bearing arrangement of claim 1 , wherein said aircraft landing gear wheel is equipped with onboard non-engine drive means controllable to move the aircraft on a ground surface during ground travel without reliance on the aircraft main engines located completely within said landing gear wheel internal volume.
10. The bearing arrangement of claim 1 , wherein said aircraft landing gear wheel is equipped with wheel brakes located completely within said landing gear wheel internal volume.
11. The bearing arrangement of claim 1 , wherein each of said pair of bearing elements comprises tapered roller bearings or angular contact ball bearings.
12. The bearing arrangement of claim 11 , wherein said cantilevered joint comprises a tapered roller bearing and an associated bushing interposed between cantilevered extensions of said axial portion of said inboard wheel section and said axial portion of said outboard wheel section adjacent to said axle.
13. The bearing arrangement of claim 11 , wherein said cantilevered joint comprises an angular contact ball bearing and bushings interposed between cantilevered extensions of said axial portion of said inboard wheel section and said axial portion of said outboard wheel section adjacent to said axle.
14. The bearing arrangement of claim 1 , wherein said joint between said inboard wheel section and said outer axial portion of said outboard wheel section and said cantilevered joint comprise contact surfaces and at least one contact surface in each of said joint and said cantilevered joint comprises a coating selected to allow contact between contact surfaces while protecting said landing gear wheel internal volume from external contamination.
15. The bearing arrangement of claim 14 , wherein said coating comprises a low friction coating.
16. The bearing arrangement of claim 1 , wherein said inboard wheel section axial portion is shorter than said outboard wheel section axial portion adjacent to the axle.
17. The bearing arrangement of claim 1 , wherein said inboard wheel section is formed of a thermally conductive material comprising aluminum alloy.
18. The bearing arrangement of claim 1 , wherein said joint between said axially extending inboard wheel section and said outer axial portion of said outboard wheel section adjacent to the tire comprises contact surfaces without bearing elements.