| 摘要 |
<p>The method of levelling a caravan stationed on a hillside or other sloping surface uses a swinging beam attached to respective wheels on opposite sides of the caravan. When one beam is swung upwards about a horizontal axis remote from the wheel axis, the other beam is swung downwards about the same amt. Thus one wheel is lifted as the other wheel is lowered. The common axis is formed by tension bars extending inwards from the two beams, attached to a drive which rotates each set of tension bars in the opposite direction to the other. The drive consists of two right angle helical drives between the torsion bars and two parallel shafts at right angles to them. One shaft is driven through an extension and carries a gearwheel which meshes with a gearwheel on the other shaft, thus ensuring that the parallel shafts rotate in opposite directions.</p> |
