| 摘要 |
<p>A ramp assembly comprises a wedge-shaped ramp member which is inclined on one side to present a single-phase surface (24, Figure 4) between its pointed 27 and wider 28 edges and on its other side a step. The arrangement is such that when the ramp member is in it stowed position the uppermost corner 29 of the wider edge 28 of the ramp member is positioned within the predetermined distance which is located between two points. The first point is towards the wider end 28 of the ramp and is on a straight line which passes through the pivot axis 8 of the ramp member but which is inclined at an angle of 20° to a vertical line which also passes through the pivot axis 8 and a second point positioned towards the pointed edge 27 of the ramp member and lies on a straight line which also passes through the pivot axis 8 of the ramp member but which is inclined at an angle of 10° to the a vertical line.</p> |
