US Patent 7988159 Lean-to-turn wheeled device

A wheeled device having pairs of wheels positioned on opposite sides (e.g. skateboard or “quad” skate) that includes a base and at least one turnable wheel assembly. A turnable wheel assembly includes two wheels having negative camber angle, and is configured such that the axles of the wheels can pivot about an axis disposed substantially perpendicular to the direction of travel. This configuration is conducive to the use of large wheels.