| 摘要 |
<p>A raisable and lowerable vertical platform system, wherein two or more platforms (20,30,50) at different levels are required for servicing of or access to different levels of a structure, has twist-resistant platform-to-platform connections The connections are braced arms (32,34; 52,54) pivotted together and to respective platforms (20,30,50) to move from a shallow-V (extended) to very narrow-V or adjacent (retracted) relative position viewed from a side. Interconnecting rigid guide means (41) are provided for the mutual pivots (33) of the connections.</p> |
