Staircase with paired steps joined by bolts - has bolts passing through tubular unit with ends fitting against steps

摘要

Staircase is of the type in which pairs of steps are joined to each other by bolts or screws; the object here is to enable the steps to stand up to heavy loading without deformation, or without the bolts being bent, and also to facilitate subsequent adjustment of the interval between two adjacent steps. There is a tubular sleeve (5), with the bolst (3, 4) which connect two adjacent steps (1, 2) led through it, and with its two ends fitting against these two steps. there may be an adjustable bearing surface, pref. on the lower stair in the pair, for adjustment of the interval or pitch, with a bolt or socket with one end against the tubular unit and an external thread engaging a thread in the step. The connecting bolts may be led through the socket.