US Patent 11173743 Wheel assembly

A wheel assembly includes a wheel having a surface and defining a plurality of slots and a cap having a cap surface. The cap includes a plurality of positioning posts extending from the cap surface, each positioning post including a pillar and a stop fixed to the pillar. The pillar extends farther from the cap surface than the stop. The stop has a distal end. Each pillar is received by one of the slots of the wheel and the distal end of each stop is engaged with the surface of the wheel.