Coupling for two=stage ladder - has pivot to allow stages to undergo angular displacement to form triangular structure

摘要

The coupling allows a two-stage ladder to support itself on level ground or a staircase. It comprises clamps (2) carrying fixed pivotal axes (3), which are secured to each upright of the smaller stage by releasable clips (7). The uprights of the larger stage receive brackets (B) containing recesses (C) into which the pivotal axes (3) locate. An arm (A) extends from the bracket (B) and has a folded end (D) which bears onto the upright of the smaller stage to limit angular displacement between the two stages. Each clamp carries an internal projection, which engages into the open end of a rung (E), to hold the clamp in position.