Spiral staircase on sectioned central shaft - has steps secured by adjustable shaft sections above and below, and piercing fixtures

摘要

The central shaft is composed of sections which can be form-locked together lengthways to hold steps one above the other, with a base plate fixed in the floor of the storey. The staircase steps are fixed and secured against twisting by shaft sections lying on their top and bottom sides, which can be clamped against themm and adjusted along the line of the shaft; and by one or more fixture components passing through the steps. The shaft sections may be tubular sections with a flange-type support at one end fitting on the top or bottom of the steps. The shaft sections may be fitted with end discs of smaller diameter than their top outer diameter and smaller than the inner diameter of the section which may be threaded for screwing on. Height can be adjusted without additional work on the steps.