| 摘要 |
<p>The folding surface has a surface element (5) which retains its position both with a folded surface and an unfolded surface whereby the other flat surface elements (3,4,6,7) each fold by their undersides towards this surface element which has retained its position. The surface retaining its position is preferably the centre element and its width corresponds to the combined thickness of the elements which fold underneath same. The centre element can have a carrying handle.</p> |
