| 摘要 |
<p>The folding ladder has two stringers (1) on which a number of articulated rungs consisting of arms (3, 4) are pivoted. The two rung halves are jointed together at points (6) along which a common rod (2) is connected. The bottom end of the rod extends beyond the lowermost joint and is provided with a lip. Below the lowermost rung assembly is a trestle-shaped support consisting of arms (8). The length of these arms is larger than that of the rung arms so that when the rung halves are level, the trestle shape of the support arms still provides a fixed support for the assembly when lip rests in gap (16) between the two ends of arms (8).</p> |
