Patent attributes
The invention provides a caster including two wheels, a central frame member, and a mount member. The two wheels are mounted on the mount member. The caster has a hybrid bearing arrangement comprising both a rolling bearing and two slide bearings. The rolling bearing is located between the central frame member and the mount member and is configured to enable the caster to roll along a straight line with each of the two wheels rotating in a common direction about a first axis. Each of the two slide bearings is located between the mount member and a tread portion of a respective one of the two wheels. The slide bearings are configured to enable the two wheels to simultaneously rotate in opposite directions when the caster swivels about a second axis orthogonal to the first axis. In some embodiments, the caster is a hubless caster.