Stairway for use in house, has stringer including support with elements intersected with plane to form regions that are equidistant from one another to define triangle, where apex of triangle is oriented along vertical direction in plane

摘要

The stairway (10) has a central stringer (14) including a support (16) supporting horizontal steps (12), and a connection gusset (24) fixed on a flat intermediate part (42) on which the steps are installed. The support has parallel tubular elements (18, 20, 22) extended along oblique longitudinal direction (Y2). The elements are intersected with an intersection plane perpendicular to the direction to form three regions that are equidistant from one another to define equilateral triangle. Apex of the triangle is oriented towards the bottom along vertical direction (Z2) in the plane.