Adjustable overlapping stringer element connected staircase - has tread panels with bolts in sloping slots on displaceable U:shaped parts

摘要

The tread panels on the staircase are fixed to at least one staircase beam, made up from separate overlapping stringer elements interconnected one above another. Each such element incorporates two mutually displaceable and fixable parts joined to elements above and below respectively. These two parts (5, 6) are supported against each other on sloping guideways (12). They can be U-shaped and overlapping, with sloping slits (12) in the shanks of one, for passage of bolts (13, 14) connected to the other. The bolts may be in the form of clamping screws. Tread height and width can be simultaneously adjusted while meeting the standard requirement for a constant sum of two rises plus one tread width at each stage.