| 摘要 |
A folding step ladder has a pair of front legs with a pair of back legs pivoted thereon, below which are upper and lower steps pivotably secured to the front pair of legs. A pair of spaced apart links are pivotably secured to the upper step at points rearwardly of its pivotal connections to the front legs and the other end of each link is pivotably connected to the rear legs at points below the upper step. The link members each have an abutment at this point which forms a stop for the ladder on unfolding. This is arranged through the action of a pair of arms, the upper ends of which are pivotably connected to the upper step rearwardly of the pivotal link connection thereto; the lower ends of the arms are pivotably secured to the rearward portion of the lower step. Each arm extends downwardly between an individual link and its adjacent rear leg but forwardly of the abutment to engage thereon when the ladder is unfolded.
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