| 摘要 |
<p>A wheel assembly comprising a plate having three arms (2, 3, 4) each comprising a swivel caster (5, 6) and a depending arm (8) comprising a ball and socket joint (10, 25) for connection to a vehicle to be movable. The ball and socket joint is positioned approximately in the centrum of the area encircled by the attachment points of the casters and at about the same height over the ground as the horizontal pivot axis of each caster. Preferably each arm is reinforced (11, 12) in order that the vertical axis of the caster will always be vertical to avoid any wobbling of the casters.</p> |
