| 摘要 |
1. Self-supporting outer metallic stairway with right flights of stairs, fixed to a stable column of support (4), particularly made of aluminium, provided to be mounted at the main wall or front wall (2) of a multistage building or a building of important height and particularly intended to be used for allowing the occupants of a multistage building to evacuate this one and persons to go out a multistage building or to go in a multistage building from the outside, the stairway comprising at least two right flights of stairs each made of a pair of stringers (9) and of treads (10), said flights of stairs joining story landings and/or intermediate landings (8, 18) mounted on a supporting and the landings being provided with balustrades made of uprights (19, 20) and transverse elements (5, 6, 7), wherein the column of support (4) is made of four uprights (3) that are mounted vertically in a square or rectangular arrangement, the flights of stairs are fixed on at least two opposed sides of the column of support (4), the uprights (3) of said column of support (4) are connected to one another at different levels and at least the level of the landings (8, 18) by means of several sets of four horizontal tie-bars (15, 16, 17), at least one tie-bar (17) of a first set of four horizontal tie-bars (15, 16, 17), placed a the level of a story landing (18), extending beyond two adjacent uprights (3) that it connects to one another, on the one side, either for maintaining and supporting said landing (18) overhanging or for being fixed to an already existing landing, and, on the other side, for fixing the flight of stairs descending from said landing (18), and two adjacent horizontal tie-bars (16) of another set of four uprights (15, 15, 16, 17), placed at the level of an intermdiate landing (8) extending beyond the upright (3) that they connect to two other uprights (3) for forming a part of the supporting frame of an intermediate landing (8) and for fixing to it, on one of two extended tie-bars (16) and, on the other extended tie-bar (16), the flight of stairs mounting from the same landing (8). |
