Patent ID: 7437801
Filing Date: 2008-10-21
Classification: B60B,B62B,Y10T

Abstract:
1. A cart caster unit comprising: (a) a pneumatic tire featuring a hub fixed to and disposed within said tire; (b) a hollow tube axle extending through a central channel of said hub, said tube axle connecting to a horn by securing means at opposite ends of said hollow tube axle; (c) said horn connecting to the underside of a bearing retainer unit, said bearing retainer unit having an upper bearing cap; (d) where a tube stem extends through said bearing retainer unit, (e) wherein said tube stem is defined by a solid lower base portion adjacent the upper bearing cap, and a tubularly hollow, upper portion the solid lower base portion being solid throughout a cross-section thereof; (f) wherein the tubularly hollow upper portion defines up to 80% of said exposed portion of an tube stem, said exposed portion of the tube stem being the portion of said tube stem disposed above said upper bearing cap; and, (g) wherein the entire caster unit is in the range of 3 to 5 pounds.