| 摘要 |
1494312 Ladders P HUGHES 22 Nov 1974 [7 Sept 1973] 42189/73 Heading E1S A ladder comprises a pair of riged side members 1 and rigid rectangular frames 2 each providing two rungs 3, each frame side 4 being detachably secured to each side member at two spaced points 5. Such a ladder unit may be connected to other similar units, by spigot and socket joints between the ends of the side members, to form long ladders, free-standing ladders, step-ladders, and trestles. The side members and frames may be of tubular metal, and the joints may comprise separate tubular spigots inserted and pinned in the side member ends, (Fig. 3, not shown). Angled connectors 18 with spigots 18<SP>a</SP> may connect a pair of ladders at their converging upper ends. A ladder foot comprises a groundengaging transverse tube carrying a pair of spigots for insertion in side member ends, (Fig. 10, not shown). The ladders may be provided with treads and platforms. |
