| 主权项 |
1. A multi-wheel caster wheel assembly comprising:
at least two hubs, each said hub comprising a generally annular body centered about a common central axis, each said hub having an outer peripheral rim section and an inner bearing section, each said rim section including an annular outer rim surface having an annularly dished concave region disposed between a pair of cylindrical lips, at least two treads, each said tread surrounding a respective one of said rim surfaces, each said tread having a convex inner periphery conforming to said annularly dished concave region of said rim surface in a tight nested relationship, each said tread including a cylindrical pad on each side of said convex inner periphery, said cylindrical pads disposed in direct surface-to-surface contact with said cylindrical lips of a respective one of said rim surfaces, wherein said annularly dished concave region of each said outer rim surface has a parabolic OD cross-section, wherein said parabolic OD cross-section is defined by the equation y=A*x2, where A is between 1.5 and 4, and further including a bearing disposed inside said inner bearing section of each said hub, and a bushing having a cylindrical outer surface disposed inside each said bearing. |
