| 摘要 |
A trolley (10), including a trolley frame (12), a plurality of wheels (14,16), (18,20) mounted to the frame (12) for supporting the trolley (10) thereon, and a direction control wheel (22). The direction control wheel (22) is connected to the frame (12) and displaceable relative to the frame (12) between at least three positions, the at least three positions including a ground contact position, a ground clearance position and an obstacle negotiating position. The direction control wheel (22) is provided for controlling the direction of travel of the trolley (10) when in the ground contact position. The direction control wheel (22) is operably movable between the ground contact position and the ground clearance position, and independently movable between the ground contact position and the obstacle negotiating position. Further, the direction control wheel (22) is independently movable between the ground clearance position and the obstacle negotiating position. |
