Metal ladder with U=section or T=section side stringers - having ribs to locate reinforcement plates which receive selected rung ends

摘要

The metal ladder has side stringers formed of U or I section members, each being reinforced opposite the ends of some of the rungs by counter plates (4). The longitudinal walls (1b) of the stringers include returns (Ic) forming ribs (1d). Each of the returns has apertures to receive teeth or ribs on the counter plates each rung (2) having a shoulder located against the stringer. The outer end of the rung is formed with a retaining lip for the counter plate. The counter plates strengthen the rung mountings, and laterally position the rungs. This provides a light ladder construction which is safe to use.