Patent ID: 8578984

Claim:
A wheel for a human-propelled cart, the wheel comprising: a housing assembly comprising a hub and a cover, the hub having an inner cavity and comprising a frame engaging surface having a second mating feature, the inner cavity configured to receive an electrical component, the cover configured to be sealed with the hub, thereby inhibiting access into the inner cavity; a tread assembly configured to axially receive a portion of the housing assembly, the tread assembly comprising a frame and a tread, the frame comprising a tread engaging surface and a hub engaging surface, the hub engaging surface having a first mating feature and being configured to releasably couple with the frame engaging surface of the hub, the tread disposed radially outward of the frame, the tread configured to engage a surface on which the wheel is configured to roll; and a fastener configured to engage the second mating feature of the frame engaging surface and the first mating feature of the hub engaging surface; wherein the tread assembly is configured to removably couple with the housing assembly such that the tread assembly can be axially separated from the housing assembly without unsealing the cover and the hub, thereby facilitating repair or replacement of the tread assembly while maintaining the seal of the cover and the hub, and wherein, when the hub engaging surface of the frame is coupled with the frame engaging surface of the hub, the first mating feature and the second mating feature are circumferentially aligned such that the fastener can axially engage the first mating feature and the second mating feature.