| 摘要 |
FIELD: construction.SUBSTANCE: method to manufacture scaling folding ramp ladder from composite materials includes assembling sections in the form of a rigid spatial frame from truss bowstrings with stands, which are used to connect upper and lower longitudinal beams of box-shaped profile with tips near meeting ends and upper and lower units of section connection, which are fixed in opening ends of beam, and from transverse links of truss bowstrings in the form of a deck, which is fixed on upper longitudinal beams and is supported with a central longitudinal box-shaped beam in the form of a box-shaped crosspiece, which is fixed in stands near connection units, and also in the form of tubular crosspieces, which are fixed in lower longitudinal beams, besides, transverse links and longitudinal beams are made of unidirectional fibres of a composite material, such as glass-, organo- or coalplastic, at the same time longitudinal beams prior to assembly are molded by longitudinal impregnated binding glass tapes, laying the latter to form "?"-shaped profiles, and arranging them oppositely to each other one inside the other, providing for availability of larger quantity of glass tape layers on side walls of beams compared to the upper and lower shelf, and for fixation of tubular crosspieces, holes are made in inner walls of appropriate beams, the crosspiece itself is inserted until stop into the beam with a gap between shelves, sufficient to locate the fringe of the crosspiece end, which is made from one-three layers of glass plastic with coverage of the crosspiece wall and its bending inside the crosspiece, with the coverage value sufficient for placement of the fringe with a thrust between beam walls, besides, the stands of truss bowstrings are made of sheet glass plastic and are fixed with external walls of beams with fastening elements, apart from the stands near meetings ends, which are made of three-six layers of glass plastic, using which, upper and lower beams are jointly moulded, at the same time near opening ends of the beams the stands are supported with box-shaped stops, which are installed with a thrust between lower beams and the box-shaped crosspiece, which is installed directly under upper and central longitudinal beams. Also a scaling folding ramp ladder is described from composite materials.EFFECT: improved manufacturability and quality of moulding of main bearing beams, easier removal of bubbles from under every layer of a tape, increased manufacturability and quality of connections of longitudinal elements of a structure and transverse links, increased reliability of ladder operation due to higher strength of elements and increased bearing capacity of main bearing elements by stability, higher quality of beam surfaces, reduced weight of a structure, increased convenience of operation and universality of application.13 cl, 14 dwg |
