FR2736077A1 - Reinforced roof covering providing top lighting for buildings, providing protection against weather - Google Patents

Abstract

The roof covering has a surface which provides protection against the weather (S) and below this a layer of flexible cables (5) held under tension and all running in the same direction. The cables are positioned a few centimetres below the covering. The cables have a central core surrounded by twisted wire and are partially made of steel. The cables have two sections joined by a helical spring. One of the cable ends is attached to a helical spring. The roof covering or sections of covering are fixed to two end pieces (2) as are the cables. There are further cross pieces (4) positioned parallel to the end sections. The covering can take the form of a self supporting arch with an arched frame to support the cables.

Description

Reinforced overhead or overhead lighting device. especially for building roofs
The invention relates to an overhead or overhead lighting device, intended in particular to constitute all or part of building roofs, reinforced so as not to undergo collapse under the action of an energy shock even greater than a about a thousand joules.

 At present, the protection and safety of personnel required to carry out verification, maintenance or repair operations, while traveling on the roofs of buildings, for example industrial buildings during operation, is only imperfectly insured.

 Indeed, many roofing materials are very fragile to shocks (corrugated asbestos cement plates, plastic plates), and the problem arises with at least as much acuity for overhead lighting devices such as shooting arches, point skylights, sloping roofs known as sheds, constructed from glass plates, polyvinyl chloride, polycarbonate, methacrylate, polyester laminate, etc.

 This is why a standard has been established defining a test to be met by roofing and overhead lighting devices, this standard requiring that for roofs, materials or permanent protective devices capable of absorbing corresponding shocks be used. at an energy of 1,200 joules, so as to prevent an average adult human being falling through the overhead or overhead lighting device.

 It is known, in order to prevent the fall of a person on a roofing or overhead lighting element resulting in a race of several meters, to have a net or a bar for example in steel tubes under the elements. However, the nets are relatively degradable, and the bars themselves generate injuries.

 The other known devices intended to meet this standard, for example plates of internally reinforced material, are often complex to manufacture, expensive, heavy, or difficult to install; in addition, most of them have a relatively tight mesh partially obscuring the light.

 The object of the invention is to remedy these drawbacks and to this end relates to a reinforced overhead or overhead lighting device, in particular for building roofs, of the type comprising at least one overhead or overhead lighting element constituting a weather protection surface, characterized in that it also comprises, under the protection surface, at least one ply of flexible cables kept in tension and extending substantially in the same direction.

 Thanks to this structure, even if the covering or lighting material is broken by the shock of a human being, the fall of this one is interrupted thanks to the absorption of part of the energy of the shock, by the elastic deformation of the sheet.

Other characteristics and advantages of the invention will appear on reading the description which follows, of embodiments of the invention given by way of nonlimiting examples and shown in the attached drawings in which
FIG. 1 shows diagrammatically in perspective, an overhead lighting device according to the invention in the form of a domed skylight fitted to a terraced roof,
FIGS. 2A, 2B, 2C show diagrammatically in cross section the skylight of FIG. 1 and two variants, respectively,
FIG. 3 schematically shows in cross section the impact behavior of the skylight of FIGS. 1 and 3A,
FIG. 4 shows diagrammatically in perspective, an overhead lighting device according to the invention in the form of a canopy,
FIG. 5 shows diagrammatically in perspective, an overhead lighting device according to the invention in the form of a sloping roof,
FIG. 6 shows diagrammatically in perspective, an overhead lighting device according to the invention in the form of a flat point skylight of square shape, and
- Figure 7 shows schematically in perspective, a covering device according to the invention on a building comprising conventional trusses.

 The overhead lighting or covering devices shown in the figures comprise a covering or overhead lighting element 1 or a set of such elements 1 juxtaposed, in the form of plate (s), to constitute a surface for protection against bad weather S, and in particular a surface which is waterproof and relatively thermally insulating.

 This protective surface S is carried either directly by a masonry or carpentry structure M erected on the roof T of the building to be covered and / or to be lit, or by the gable walls P and facade F of the building, or by the 'through a support. Such a support comprises for example two crosspieces 2 between which extends the lighting or covering element 1, two opposite end edges of which are fixed to these crosspieces 2 respectively, or between which an alignment of several elements 1 arranged end to end, each of the end elements having its free edge fixed to a cross-member; the crosspieces 2 can be connected by beams 3 so as to form a frame, more particularly in the case of overhead lighting devices or of very long cover; in this case, additional crosspieces 4 can follow one another at regular intervals along the device, for supporting or fixing the junction of the elements 1 juxtaposed end to end.

 According to the invention, under this protective surface S, are arranged flexible cables 5 maintained in tension and extending substantially in the same direction, so as to form a ply, elastically deformable, at any point as equidistant from the protective surface S.

The ends of the flexible cables 5 are fixed, as the case may be, to the masonry or joinery work M carrying the protective surface, or to the walls P, F of the building, or to the end crosspieces 2, or more generally to any additional structure adapted to ensure the absorption of the energy of the shock and the retention of the cables and possibly of the protective surface, which can be broken by the shock without serious inconvenience provided on the one hand that the material which constitutes it is not sharp and on the other hand that the cable layer 5 under tension fulfills its retaining function in the event of the fall of a human being. The cables 5 can be anchored directly to the masonry work or in carpentry, to the walls, to the crosspieces, or to the complementary structure, or to be connected to it by at least one elastic member (not shown in the figures) such as a helical tension spring, absorbing the impact of the shock at ni anchor calf; one can for example have a helical spring at one end of each cable, or at each of the ends; it is also possible to have a cable in two sections connected by an elastic member.

The anchoring (symbolized in 6) of the cable 5 or of the elastic member is carried out for example by means of a cable clamp or a crimping collar.

 The flexible cables 5, intended to undergo a certain elastic deformation under impact, can in particular be at least partially made of steel, and for example comprise a central core and six strands braided around this core.

 The spacing of the cables 5 between them depends on the nature of the material constituting the weather protection surface S, and for example the use of polyester elements 1 requires cables 5 closer together than the use of elements polycarbonate, and it is the same for the spacing of the cables with respect to the protective surface.

 In a particular exemplary embodiment in which overhead lighting elements l are sheets of cellular polycarbonate, the tests were conclusive with cables 5 spaced apart from one another by about sixty centimeters and a sheet of cables spaced twenty thirty millimeters from polycarbonate sheets; the overhead lighting device being of relatively great length, intermediate crosspieces 4 follow one another between the end crosspieces 2 at intervals of the order of 1.5 meters.

 In most cases, the appropriate spacing of the cables 5 between them is a few tens of centimeters, and the appropriate spacing of the cable ply with respect to the protective surface S is a few centimeters.

 The domed skylight shown in FIG. 1, placed on a terraced roof T, rests on a masonry structure M, but has cross members 2 carrying the lighting elements 1, namely two end cross members 2, and two cross members intermediates 4, and two beams 3. The crossbeams being arched in arcs of circumference extending in parallel vertical planes, the cables 5, so as to be both taut and sufficiently free to constitute an elastically deformable sheet, at any point approximately equidistant of the protective surface S, are fixed and stretched between the end crosspieces being arranged longitudinally with the skylight, that is to say in the direction of the generatrices of the cylindrical surface formed by the protective surface. FIGS. 2A at 2C show the substantially regular distribution of the cables 5 along the contour of the cross section of the protection surface S, at short distance e substantially constant of the latter.

 Figure 3 shows in section, schematically, the profile taken by the protective surface and by the underlying ply, in the case of Figure 1, during an impact produced by the fall of a human body, as a result the deformation of the elements 1 constituting the protective surface S, and jointly the elastic deformation of the cables 5 constituting the sheet.

 FIG. 4 shows a flat canopy carried by a masonry structure M having a cross section in a rectangular trapezoid, with its cables 5 anchored to the end crosspieces 2, and five intermediate crosspieces 4 succeeding one another in the direction in which the cables.

 FIG. 5 likewise shows a very long sloping roof. In the case of great lengths, the cables 5 may possibly be anchored to one or more intermediate crosspieces 4 depending on the length, or be supported in bridges carried by these crosspieces, while remaining free to slide longitudinally in these bridges.

 As seen in Figure 6, the direction in which the cables 5 extend in the case of a square skylight can be arbitrary; the cables could even extend in a diagonal direction.

 FIG. 7 shows that a roof comprising conventional trusses or small farms can also be equipped according to the invention if the roof elements are considered too fragile; as in all cases where the protection surface S is flat, the problem of equidistance at all points, of the cable ply 5 with respect to the protection surface, does not arise, and the direction in which s extend the cables can be chosen according to other considerations, for example considerations of ease of assembly, or cost related to the elasticity and resistance necessary for the cables.

 Of course, the invention is not limited to the embodiments described above and shown, and we can provide others without departing from its scope. For example, in the case of self-supporting polyester arches, the device according to the invention includes a complementary structure in the form of a curved frame disposed under the plates and making it possible to hold the cables as described above.

Claims (9)

 1 - Reinforced overhead or overhead lighting device, in particular for building roofs, of the type comprising at least one overhead or overhead lighting element (1) constituting a weather protection surface (S) characterized in that it also comprises, under the protective surface (S), at least one ply of flexible cables (5) maintained in tension and extending substantially in the same direction.  2 - Reinforced overhead or overhead lighting device according to claim 1, characterized in that the sheet extends a few centimeters below the protective surface (S).  3 - Reinforced overhead or overhead lighting device according to claim 1, characterized in that the cables (5) have a central core and strands braided around this core.  4 - Reinforced overhead or overhead lighting device according to claim 1, characterized in that the cables (5) are at least partially made of steel.  5 - Reinforced overhead or overhead lighting device according to claim 1, characterized in that the cables (5) comprise two sections connected by a helical spring.  6 - Reinforced overhead or overhead lighting device according to claim 1, characterized in that at least one end of the cables (5) is connected to a helical spring.  7 - Reinforced overhead or overhead lighting device according to claim 1, characterized in that it comprises two crosspieces (2) between which extends an overhead or overhead lighting element (1) including two edges of opposite ends are fixed to these crosspieces (2) respectively, or between which extend an alignment of several covering or overhead lighting elements (1) arranged end to end whose end elements each have an edge fixed to these sleepers (2) respectively, and in that the ends of the cables (5) are connected to these sleepers (2) between which they are held in tension.  8 - Reinforced overhead or overhead lighting device according to claim 1, characterized in that the overhead or overhead lighting elements (1) are fixed to crosspieces (2, 4) succeeding each other in the direction in which s 'extend the cables (5) constituting the web.  9 - Reinforced overhead or overhead lighting device according to claim 1, of the type comprising a protective surface in the form of at least one self-supporting vault consisting of at least one overhead or overhead lighting element, characterized in which it also includes, under the protective surface, a complementary structure in the form of a curved framework for holding the cables.