| 摘要 |
<p>An extensible ladder with anti-pinch device comprises a first vertical post and a second vertical post composed of multilevel sleeves, and several cross pieces with hollow structure. The cross piece is connected with the vertical post by an annular ring (3, 36). A bearing junk ring and a cushion collar are provided in the extensible sleeve (1, 1') of the vertical post. An anti-pinch void is provided between the vertical post and the extremity piece of the base cross piece (28), the base cross piece is connected to the corresponding extensible sleeve by means of an annular ring (36) with an anti-pinch boss on the upper end, and the horizontalplane (363) on the top of the wall of the annular ring (36) is provided with a protrusion (361) for linked unlocking when the ladder is retracted. A sufficient safe interval is placed between the base cross piece and the adjacent cross piece above for anti-pinching when the ladder is retracted.</p> |
