Caster

摘要

A caster includes a mechanism that allows a wheel axle to shift rearward through a distance corresponding to the previous lag of the axis of rotation of the wheel behind the wheel bearing axis when the caster reverses its direction of advance. In a first embodiment, the mechanism includes a unit rotating a wheel axle to reverse the trail. In a second embodiment, the mechanism includes a slider allowing the wheel axle to slide horizontally.