SCREW COUPLING DEVICE FOR COVERING CURTAINS OF SPATIAL NETWORK STRUCTURES

Abstract: The invention refers to a screw coupling device (1) for covering curtains (16) of spatial network structures, comprising: a hollow body (2) fixed to the spatial network structure; a pad (13) brought into contact with said covering curtain (16); extensible means placed between said hollow body (2) and said pad (13) suitable for changing the reciprocal distance between said hollow body (2) and said pad (13) and allowing the oscillation of the pad (13) relative to said body (2).

Description: TITLE SCREW COUPLING DEVICE FOR COVERING CURTAINS OF SPATIAL NETWORK STRUCTURES. DESCRIPTION The present invention refers to a screw coupling device for covering curtains of spatial networ structures. More particularly the invention concerns a screw coupling device for covering curtains of spatial network structures self adapting to external stresses due to atmospheric agents, as wind or snow accumulated on the curtain. When covering various kind of buildings such as gyms, conference rooms, show-rooms, swimming pools, etc., there are generally employed, alternatively to traditional masonry buildings, metallic or wooden spatial network structures covered by a plastic covering curtain. Such curtains, at present, are tensioned by means of ropes, placed along the base perimeter of the curtain, downward tensioned. A spatial network structure comprises, generally, a plurality of beams connected together by means of joints or plates defining the nodes of the network structure. A method for realising wooden spatial network structures is described for example in the European patent application no. 0651099. According to the teachings of said European patent application, a connecting joint for beams suitable for building spatial network structures is obtained by a node having a plurality of metallic tubes placed radially around it, each tube being adapted to be glued into a hole made on the ends of the wooden beams. A first problem encountered in the realisation of spatial network structures is how to tension the covering curtain even in correspondence of areas far from the base perimeter . It is to be noted, in fact, that a traditional curtain resting on the beams of the network structure and tensioned prevalently from the bottom, is much more tensioned in the areas near the base perimeter, wherein the curtain is almost parallel to the direction of the tensioning force. Far from the base the curtain, on the contrary, is retained by the friction caused by the contact with the beams of the network structure. Consequently, the bottom-up tension tends to relieve itself on the network structure beams without stretching appropriately the covering curtain. Under these conditions the curtain, in the areas far from the base, is less rigid and, consequently, subject to deformations and movements. A first object of the present invention is, therefore, to provide a screw coupling device for covering curtains of spatial network structures which allows to tension easily the covering curtain. An inconvenient encountered in traditional spatial network structures derives from the risk of lacerations in the covering curtain. In fact, in presence of high loads resting on the curtain, as in case of thick snow layers, or in case of curtain movements caused by the wind, can be generated high stresses or sliding of the curtain against the points of support of the spatial network structure, which can generate a laceration in the curtain. In order to avoid lacerations in adverse environmental conditions it is possible to realise thicker curtains superimposing several layers. In this way, however, besides the higher realisation costs for both the supporting structure, which must support a greater load, and the curtain, the problem is only moved but not eliminated. In fact, although the curtain is stronger, are still present the laceration risks caused by the contact between the covering curtain and the rigid structure that, moreover, must support the higher load of the thicker curtain. Another object of the present invention is, therefore, is to provide a screw coupling device for covering curtains of spatial network structures which allows to reduce the stresses due to atmospheric agents and that avoids contacts and sliding between the covering curtain and the spatial network structure. The above and other objects of the present invention are reached by the screw coupling device for covering curtains of spatial network structures as defined in the enclosed claims. The device according to the invention allows to move away the covering curtain relative to the spatial network structure so defining an air space which can be advantageously exploited using semitransparent panels placed, even in superimposed layers, on the spatial network structure. In this way, it is possible to obtain an efficient insulation of the inside space, without the need of using insulating materials that, as it is well known, prevent the passage of light. Additional characteristics and advantages of the invention will become evident from the following description of a preferred and not-exclusive embodiment thereof illustrated in the attached drawings in which: Figure 1 is a cross section view of the device according to the invention, mounted in correspondence of a node of a spatial network structure; Figure 2 is a plan view of a plurality of beams joined to each other in correspondence of the point of Figure 1; Figures 3a and 3b show, respectively in a plan view and in a section view, a particular of the device according to the invention; Figure 4 is a top perspective view of a covering structure in which are provided a plurality of devices according to the invention. With reference to Figures 1 and 2 the screw coupling device comprises a metal supporting element 2 comprising a hemispherical hollow body which, in the shown embodiment, acts as a node of the spatial network structure. To this purpose, externally to said body 2 are welded radially a plurality of brackets 3 for fixing beams 5 converging in the node. In the shown embodiment, each beam 5 has, moreover, in its ends, a couple of plates 4 to be screwed to said brackets 3. The choice of placing the device 2 in correspondence of the nodes of the spatial network structure is not, however, restrictive, as it is possible, in fact, to provide the assembly of the device according to the invention even in other points of the spatial network structure . The body 2 has centrally a through hole 6 through which is inserted a cone-headed rod 7 entirely housed into the hollow body 2. The cone-headed rod 7 has a threaded base so that it can be fixed to the body 2 by means of a couple of nuts 8 and 9, respectively externally and internally to the body 2. On the cone-shaped head of said rod 7 is inserted a tubular element 10 having a beveled extremity, resting on the nut 9, so that it can rotate without damaging the external surface of the nut 9 which, advantageously, is provided hemispherical. On the opposite end of the tubular element 10 is welded a nut 11 into which is screwed a threaded bar 12. On the extremity of said threaded bar 12, opposite to the tubular element 10, is engaged a second tubular element 14 to which is welded perpendicularly a second support or cap 13 on which will rest the covering curtain of the structure 16 shown in Figure 4. A nut 15 welded on said threaded bar 12 acts as a support for the tubular element 14 allowing, using a common double head spanner, to adjust the extension of the bar 12 relative to the tubular element 10. Advantageously, the cap 13 has beveled edges in order to avoid lacerations in the covering curtain 16. With reference to Figure 4 the covering curtain 16 comprises a base perimetrical edge 16b, and pockets 16a, having a trunk conical shape, provided on the curtain as seats in which the caps 13 are firmly inserted. The curtain 16 is obtained joining together suitably shaped sheets in order to define the pockets 16a. The network structure, the covering curtain and the sizing of the devices object of the invention are designed by means of computer simulation procedures which allows to optimise all the building parameters as a function of foreseen load conditions. In particular, through the above mentioned computer simulation procedures, the network structure is dimensioned, the shape of the sheets is defined and the sheets cut; lastly is evaluated the length of the threaded bars and the maximum inclination of the present devices defined by the tapering of the conic head of the threaded bar. With reference again to Figure 1, the upper bases of the pockets 16a are provided with a circular edge 30 realised by the insertion of a cord 31, for example a plastic cord, in a circular channel 32 obtained fixing, internally to the curtain 16 near the top bases of the pockets 16a, one or more sheets 33. Said circular edge 30 is, therefore, a restraint for the caps 13 when they are inserted into the pockets 16a. With reference to Figures 3a and 3b it is shown a metal ring 17, used as an assembling and centering tool for the device 1, comprising two complementary parts 17a and 17b that can be coupled and inserted into a circular groove 18 provided along the internal upper edge of the body 2. The inner diameter of the metal ring 17, when the two parts 17a and 17b are coupled and inserted into the base 2, is lightly larger then the external diameter of the tubular element 10 in order to prevent its oscillation relative to the cone headed rod 7. The assembling procedure of the covering curtain 16, using the devices 1 according to the invention, provides for the assemblage of the spatial network structure, the positioning of the covering curtain 16 over the spatial network structure and the fastening of the curtain 16 by means of known means, not shown, placed along the perimetrical edge 16b. Subsequently the tubular elements 10 having, fully screwed in, the threaded bars 12 with the pads 13, are inserted on the portion 7a of the cone headed rods 7, fixed into the bases 2. The pads 13 are therefore inserted into the pockets 16a and the tubular elements 10 are co-axially locked relative to the cone headed rods 7 by means of the metal rings 17 inserted into the circular grooves 18 of the supports 2. After the insertion of the devices according to the invention between the spatial network structure and the curtain 16, it will be possible to tension the curtain rotating the threaded bars 12 operating on the nuts 15, integral to said threaded bars 12, by means of a spanner, not shown. When the tensioning process of the covering curtain is completed, the metal rings 17 can be removed from the grooves 18, therefore allowing the oscillating movement of the tubular elements 10 on the conic heads of the rods 7. When the covering curtain is exposed to static loads, such as those provided by snow, or to dynamic stresses such as those provided by wind, all the covering curtain orient itself in order to reduce the tension, as the tubular elements 10 can oscillate and rotate around the cone headed rod 7. In the example shown in Figure 1, the maximum inclination α is around 10° and is limited by the contact between the internal wall of the tubular elements 10 and the conic surface of the head of the cone headed rod 7. Naturally the above mentioned maximum value of the inclination α is to be considered simply exemplifying, being calculated as a function of the shape of the spatial network structure and of the foreseen loads for the curtain, in order to optimise the amplitude of the oscillations and rotations of the devices 1. With reference again to Figures 1 and 2, the covering realised according to the device object of the present invention can be advantageously provided with an air space for providing a better heat insulation. It is in fact possible, thanks to the distance present between the covering curtain and the spatial network structure, to provide for a plurality of panels 20, even arranged in superimposed layers, fixed by means of frames 21 to the beams 5 of the spatial network structure. In correspondence with the nodes of the spatial network structure, said frames 21 have holes 22 having a diameter suitable for the passage and the oscillation of the tubular elements 10. In order to convey the ascending air flows originating inside the building, some metallic drilled collars 23 are inserted into the circular grooves 18 instead of the metal rings 17. The conveyance of the air through said metal collars 23 allows, moreover, the removal of humidity eventually condensed into the air space. For the scavenging of the air from the inside of the air space defined between the curtain 16 and the panels 20, can be provided, on the covering curtain 16, one or more chimneys (not shown) . In case are provided the collars 23, these must be inserted into the device 1 before inserting the pad 13, moreover, before inserting the metal rings 17 in the grooves 18 of the bases 2, it will be necessary to lift the collars 23. Advantageously the collars 23 can slide along the rod 12 in order to allow the insertion of the metal rings 17 during the tensioning operations.

Claims: CLAIMS 1. A screw coupling device (1) for covering curtains (16) of spatial network structures, comprising: - a first supporting element (2) fastened to the spatial network structure; - a second supporting element (13) brought into contact with said covering curtain (16); - extensible means placed between said first supporting element (2) and said second supporting element (13), said extensible means being suitable for changing the reciprocal distance between said supporting elements (2, 13) , so that said curtain (16) can be moved away or brought near relative to said structure. 2. A screw coupling device (1) according to claim 1, wherein said extensible means can oscillate relative to at least one of said first and second supporting element (2, 13) . 3. A screw coupling device (1) according to claim 2, wherein said extensible means can rotate relative to at least one of said first and second supporting element (2, 13) . 4. A screw coupling device (1) according to claim 2, wherein said second supporting element comprises a substantially circular shaped pad (13) having beveled edges. 5. A screw coupling device (1) according claim 2, wherein said extensible means comprise two tubular elements (10, 14) and a threaded bar (12), placed between said tubular elements (10, 14) and partially inserted into them, said threaded bar (12) being provided with a couple of nuts (11, 15) on which said tubular elements rest, said nuts can be approached and moved away one to each other along said bar causing the moving away and approaching of said tubular elements . 6. A screw coupling device (1) according to claim 5, wherein a first one of said nuts (11, 15) is welded to a first one of said tubular elements (10, 14) and a second one of said nuts is welded to said threaded bar (12) . 7. A screw coupling device (1) according to claim 6, wherein a first one of said tubular elements (10, 14) is integral to one of said first and second supporting element (2, 13) and a second one of said tubular elements (10, 14) is removably fixed relative to the other of said first and second supporting element (2, 13) . 8. A screw coupling device (1) according to claim 7, wherein the removable fixing of said tubular element (10, 14) relative to said supporting element (2, 13) is obtained by means of cone headed rod (7) integral to said supporting element (2, 13) on which is inserted said tubular element (10, 14) . 9. A screw coupling device (1) according to claim 8, wherein said first supporting element comprises an hollow hemispherical body (2) . 10. A screw coupling device (1) according to claim 9, wherein said cone headed rod (7) is substantially housed into said hemispherical hollow body (2) with the conic head turned towards the outside of said hemispherical hollow body (2) . 11. A screw coupling device (1) according to claim 10, wherein said cone headed rod (7) has, in correspondence of the base of the conic head, an hemispheric annular resting portion on which rests said tubular element (10, 13) which is removably fixed onto said cone headed rod (7) . 12. A screw coupling device (1) according to claim 11, wherein said tubular element (10, 14), which is removably fixed on said cone headed rod (7), can rotate of 360° relative to said rod and can oscillate relative to said cone headed rod (7) . 13. A screw coupling device (1) according to claim 1, wherein said first supporting element (2) comprises externally a plurality of radial brackets (3) for the connection of the beams (5) of said spatial network structure. 14. A screw coupling device (1) according to claim 10, wherein are provided removable locking means (17a, 17b) for preventing said oscillation. 15. A screw coupling device (1) according to claim 14, wherein said removable locking means comprise a decomposable metal ring (17a, 17b), suitable for being inserted in a circular groove (18) provided in the internal edge of said hemispherical hollow body (2) . 16. A screw coupling device (1) according to claim 15, wherein said metal ring (17a, 17b) has a hole having a diameter lightly larger then the external diameter of the tubular element (10, 14), preventing in this way the oscillation of said tubular element (10, 14). 17. A screw coupling device (1) according to claim 10, wherein are provided aerating means (23) suitable for allowing the entrance and the leaving of the air towards and from an air space defined between said covering curtain (16) and a plurality of panels (20) placed on said spatial network structure. 18. A screw coupling device (1) according to claim 17, wherein said aerating means comprise a drilled collar (23) , suitable for being inserted in a circular groove (18) provided on the internal edge of said hemispherical hollow body (2) . 19. A screw coupling device (1) according to claim 18, wherein said drilled collar (23) has an internal diameter larger then the maximum diameter reachable by said tubular element (10, 14), without interfering therefore with the oscillation of said tubular element (10, 14). 20. A covering structure, comprising a supporting spatial network structure and a covering curtain (16) placed on said supporting structure, characterised in that between said spatial network structure and said covering curtain (16) is provided at least a a screw coupling device (1) according to any of claims 1 to 16. 21. A covering structure according to claim 20, wherein said covering curtain (16) comprises a plurality of sheets joined together and wherein said sheets are so shaped to define a plurality of pockets (16a) having a substantially trunk-conical shape suitable for receiving said second supporting elements (13) . 22. A covering structure according to claim 21, wherein said pockets (16a) are provided with a circular edge (30) near the upper bases acting as restraint for said second supporting elements (13) when they are inserted into the pockets (16a) .

Inventors: POTITO PEDONE, POTITO, PEDONE
Applicants: POTITO PEDONE, WOOD SYSTEM S A S, POTITO, PEDONE, WOOD SYSTEM S.A.S.
Application year: 1999
Main classification: E04B1
IPC codes: E04B1