FI81167B - Roof construction - Google Patents

Description

χ 81167

roof structure

Eo. The invention relates to a roof structure in which a plastic cover film is tensioned between elongate support members, the cover film comprising a plurality of substantially extensible cover film elements permanently attached to each other by seams reinforced with substantially non-stretch stiffeners.

Roof structures are known in the art in which the roofing material is a plastic film. Because the plastic film stretches, it cannot be stretched directly between the arches, beams and / or slats, but must be supported. U.S. Patent No. 3,765,134 discloses a roof structure in which a plastic film of stretchable material is supported and anchored between two layers of elements such as wires or ropes stretched between arches and / or beams. Such a structure is expensive and very laborious to erect.

It is also known that elastic plastic can be reinforced by melting a reinforcing material inside the plastic. GB Patent 1,524,110 discloses a lifting strap consisting of two interconnected, flat plastic strips with a plurality of longitudinal bundles of fibers between them. There is also a fiber bundle grid in the wall of the pressure-resistant plastic hose. However, these structures would be too expensive when applied to plastic roofing films.

Very strong plastic cover films made by impregnating a fiberglass fabric with plastic, e.g. in the form of a dispersion, are also known in the art. The production of such a plastic-impregnated and coated textile is expensive and the impregnable plastic is often not very weather-resistant.

Eo. The object of the invention is to provide a roof structure by means of which the above-mentioned disadvantages can be eliminated. The invention is thus mainly characterized by what is stated in the claims. The roof structure is thus provided with a stretchable plastic, which can thus be used as a building component of a self-supporting roof. The reinforcement acting as part of the joint is very inexpensive and its connection to the joint can be achieved by means of conventional technology.

The elongate support members of the roof structure are typical of the so-called arches, beams or ribs supporting the fabric of fabric buildings. The cover film is either firmly attached to the support members, after which the structure is tensioned, e.g. Eo. the plastic film according to the invention does not create rainwater-collecting depressions due to the elongation of the plastic.

The shape of the canopy elements depends on which and from how many directions the canopy film is stretched. Because the seams strengthen the multifilament in the tensile direction, most seams are needed in the direction where the tensile stress is greatest. Thus, in the case where the cover film is attached and tensioned between arches or beams in different directions, or points, there is also a need for reinforced seams in different directions. The preferred roof structure is obtained when the roofing film is fastened and tensioned between parallel arches or beams, in which case only parallel reinforced seams perpendicular to the arches or beams are required. Then the preferred canopy elements are strips running in the tensioning direction.

The cover film elements are preferably sealed together by heat sealing. Namely, heat-sealing has the advantage that the edges of the elements melt and adapt to the elongate reinforcement so that no protrusion due to the reinforcement occurs at the joint. In this case, however, the heat-sealing must be so wide that the reinforcing-free seamed contact surface is sufficient to hold the cover film elements together.

3,81167

The joint reinforcement can be fabric, filament, roving, fiber bundle, wire or string. The shape of the reinforcement depends on the magnitude and direction of the stresses on the roofing film. For the above-mentioned preferred parallel tensioning method in which the seams are parallel, a reinforcing wire or rope with high tensile strength is preferably required. The reinforcing material is preferably glass and / or carbon fiber.

The material of the cover film elements is plastic, preferably heat-sealable and weatherproof plastic. Thanks to the reinforcements, it does not have to be strong or unstretchable. The cost-effective and otherwise advantageous plastic for the invention is plasticized PVC, which is very flexible and weather-resistant.

Eo. the roof structure according to the invention can be used for shelters, canopies, tents, textile buildings, etc. purposes.

The invention will now be described in more detail with reference to the drawings, in which Fig. 1 shows a perspective view of a roof structure according to an embodiment, Fig. 2 shows a partial perspective view of an embodiment of a joint between roofing elements, Fig.

In the embodiment shown in Figure 1, the cover film 1 is tensioned like two tents over two parallel arcs 2. Since the main direction of the tension stress is perpendicular to the arc 2, the cover film is formed by strips 4 connected in the tension direction by means of reinforced seams 3. The cross lines show either the cover film in general or the cross seams of the patch elements. The cover film 1 can either be firmly attached to the arches 2 and the arches are tensioned, e.g. The advantage of the roof structure shown in Fig. 1 compared to the prior art roof structure made of plastic-impregnated nonwoven fabric is that the cover film formed of reinforcing seams and plastic strips is much cheaper than impregnated nonwoven fabric, but still strong enough and weatherproof.

In Figure 2, the strips 4a and 4b are seamed, preferably heat-seamed together, and a seam-directed fiber bundle or fiber wire 5 is embedded in the seam 3. In Figure 3, seam 3 includes three seam-oriented fiber bundles or cables 5 and in Figure 4 individual fibers, woven fabric or oriented roving.

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Claims (6)

5,81167 A roof structure in which a plastic cover film (1) is tensioned between elongate support members (2), the cover film (1) comprising a plurality of substantially extensible cover film elements (4) permanently attached to each other by seams (3), said seams (3) is reinforced with substantially inextensible reinforcements (5, 6), characterized in that the seams (3) of the cover film (1) are formed by hot welding the edges of the cover film elements (4) on top of each other so that the reinforcements (5, 6) remain between them. Roof structure according to claim 1, characterized in that the elongate support members (2) are parallel arches, beams or ribs over which a cover film (1) is stretched perpendicularly, the roof film elements being strips perpendicular to said arches, beams or ribs ( 4). Roof structure according to Claim 1 or 2, characterized in that the reinforcements (5) are made of glass fiber and / or carbon fiber. Roof structure according to Claim 1, 2 or 3, characterized in that the reinforcements (6) are wires or cords. Roof structure according to one of the preceding claims, characterized in that the substantially stretchable roofing element (4) is plasticized polyvinyl chloride. 6 81167