FR2774403A1 - Illuminating system for incorporating in concrete structures - Google Patents

Abstract

Optical fiber cables (312) are incorporated within the structure as it is being molded and are routed down to a central light source (42,43). The fibers terminate at the surface of the structure to provide a predetermined display arrangement (11). To achieve this, the fibers are embedded in a preformed insert (3) to protect them from the stress incurred during the molding process and to hold them in the required position.

Description

 The present invention relates to a concrete product such as a road sign, bollard, street furniture, or building elements of any kind, equipped with lighting and / or light signaling signals with optical fibers supplied from a light source centralized by the optical fibers being at least partially integrated into the body of the concrete product at the time of its manufacture to form light spots on the surface of the body.

 The invention also relates to a mold and a method for manufacturing such a product.

 It is already known to integrate optical fibers into concrete products such as products used for signaling or road markings, such as for example lane dividers, bollards, etc.

 According to the known technique, these products are molded in concrete. Before molding, optical fibers are fixed in the mold. So that these optical fibers hold and resist the pouring of concrete, they pass through the wall of the mold.

 The fibers thus fixed in the desired places, open corresponding holes in the mold. Then pour the concrete into the mold. It is only after taking that the product is removed from the mold. By demolding, the fibers are sheared between the surface of the concrete product and the surface of the mold.

 This known process has a number of drawbacks, the most serious of which is that it requires the concrete to set completely before it can be removed from the mold. Under these conditions, a relatively large number of molds is required for a large production since each mold is immobilized during the entire setting and drying time of the concrete. If we tried to demould prematurely, the fibers could not be sheared cleanly on the surface of the product; it would flake or deform and in all cases the fiber would not be in the right place; it would be partially torn off or torn.

 During the pouring of the concrete and its setting, the optical fibers undergo various mechanical stresses which deteriorate their optical characteristics.

 In addition, the force exerted at the time of demolding by the shearing movement between the mold and the concrete product in the outlet to be finished, induces in the fiber significant stresses which deteriorate its optical qualities.

 Finally, the placement of the fibers in the mold is a delicate operation because it is necessary to thread each fiber into a hole in the wall of the mold and block it so that it does not come off when the concrete is poured into the mold. The fibers must also be protected so as not to be directly exposed chemically to the concrete and the admixtures it contains, and which risk aging or premature deterioration of the physicochemical or optical characteristics of the fibers.

 Finally, this known product and its manufacturing process have a very high design rigidity since the mold has holes for precise positioning of the fiber ends; it is not possible to modify the positioning of these fibers unless new holes are drilled in the wall of the mold.

 In other words, it is practically not possible to modify the location of the light points of the product on demand, for example to draw or trace light letters or generally modify the position of the light points in according to the needs of the signaling or lighting.

 In addition, known products have light points formed by the sheared surface of the fibers. Although in general and in principle this shear surface must be clear, this is not always the case in practice.

The main direction of the light beam emitted by each fiber surface may be different from the orientation desired for the direction of the light beam emitted by the fibers.

 These various drawbacks constitute obstacles to the development and installation of concrete products equipped with lighting and signaling elements.

 The present invention aims to remedy these drawbacks and proposes to create a concrete product whose light points can be chosen very variably, practically from one product to another, whose optical fiber is perfectly protected against the physico-chemical influence of concrete, which does not undergo sudden stresses and transformations at the time of demolding but, on the contrary, guarantees the precise positioning of the fibers and especially of the emitting surfaces of the fibers, and all this with simple means.

 Another object of the invention is to create a method and a mold making it possible to manufacture concrete products equipped with lighting and light signaling elements by optical fibers in a simple and efficient manner, while retaining the diversity of positioning possibilities. luminous spots on the surface of the body of the concrete product thus produced.

To this end, the invention relates to an insert with branches from a basic element,
arriving directly at the surface of the concrete body at
the location of the light points,
optical fibers housed in the branches and arriving at
the outer surface of the branches to form the points
luminous.

 The product thus obtained has the advantage of very high precision of the position of the light points as well as of the shape of the light beam coming from each of the points. In addition, the optical fibers are perfectly protected during the relatively brutal operations of pouring concrete into the mold and demolding. Since the fibers are never stressed in tension, compression or shear, they perfectly retain all their optical characteristics (transmission), allowing excellent light output for the device.

 The invention can be applied to the manufacture of the most diverse products, with extremely varied shapes. In particular, the invention allows the manufacture of concrete products for road signs or even street furniture elements. The invention also makes it possible to integrate a lighting or illumination system for facades in constructions by producing construction elements equipped at the time of their manufacture with lighting means.

 According to an advantageous characteristic, the basic element of the insert is a hub from which branch branches in the form of spokes into which the optical fibers are integrated.

 In general, the studs or terminals include a ring of light points and it is therefore particularly advantageous for the branches of the insert to be located in the same plane.

The invention also applies to products having a shape different from a shape of revolution, for example a prismatic shape or an elongated shape of variable section and in this case the insert comprises a basic element in the shape of a bar. '' from which branches distributed in several layers around the basic element and arriving at the facets of the product
Finally, it is perfectly possible to integrate several inserts in the same product, for example a bollard, to create several zones of light points, distributed in height or along axial planes.

 In a particularly advantageous manner, the material of the insert is transparent and the ends of the branches cover the emission surfaces of the fibers by forming optical elements defining the shape of the emission beam.

 According to a variant, it would also be possible to integrate into the material of the insert, at the time of molding the insert on the fibers, optical elements carried by the end of the fibers. In this case, the material of the insert may not cover the ends of the fibers provided beforehand with the optical elements. This may be advantageous for reasons of resistance or, more generally, of choice of the material constituting the insert.

 The invention also applies to means for the manufacture of products such as those defined above.

 Such a means is characterized in that it consists of a mold defining the external shape of the product to be obtained receiving the insert, the external surfaces of the branches of which come to bear against the corresponding surface of the mold and a tube of reservation provided in the upper part with a positioning support for the insert, outside the volume which will be occupied by the poured concrete.

 To facilitate the positioning and holding of the insert in the mold, it is advantageous for the insert to have a receiving surface on which the end of the tube engages.

 In a particularly advantageous manner, the receiving surface is a thread capable of receiving a connection means for the optical supply of the pad of the insert.

 However, this threaded receiving surface with a corresponding threaded part of the tube is not the only solution. The tube can also be simply engaged by a smooth connection on the receiving surface of the insert.

 Finally, the invention relates to a process for manufacturing a concrete product with the means as defined above, characterized in that the mold is placed in the inverted position relative to the normal position of the product, the one or more is installed. inserts in the mold, these inserts having been previously molded with optical fibers arriving at the outer surface of the branches, the insert is fixed in the mold and the concrete is poured and then unmolded after a short period, without waiting for the end concrete drying.

The present invention will be described below in more detail with the aid of the accompanying drawings in which
FIG. 1 is a schematic sectional view of a first example of a concrete product in the form of an illuminating bollard according to the invention,
FIG. 2 is a section of another product according to the invention,
FIG. 3 is a very simplified plan view of a product of the type of that of FIG. 2,
- Figure 4 is a sectional view of the product of Figure 1 during molding.

FIG. 5 is a view in axial section of an exemplary embodiment of an insert,
FIG. 6 is a partial top view of the hub according to FIG. 5,
- Figure 7 is an enlarged view of the end of a branch of the insert corresponding to the detail
VII of Figure 5,
- Figure 8 is a sectional view along VIII
VIII of Figure 5,
FIG. 9 is an enlarged view of the connection between an insert and its holding tube,
- Figure 10 is a view similar to that of Figure 9 showing the insert after its optical connection.

 According to Figure 1, the invention relates to the most diverse concrete products such as for example a terminal 1. This terminal 1 has at its periphery light points 11 corresponding to the end of optical fibers integrated into an insert 3 with branches 32, radiating from a hub 31 forming the basic element. The optical fibers 311 arrive at the surface 12 of the concrete body at the location of the light points 11. The branches 31 of the insert 3 are for example placed in the same plane or at least the light points 11 correspond to a peripheral distribution or longitudinal depending on whether the product 1 is a product in the form of a revolution or a parallelepiped or more generally prismatic. Inside the product 1, a channel 13 allows the passage of an optical cable 312 grouping for example the fibers 311 of the branches 31 or supplying the latter at the level of the insert 3.

 The product 1 is installed at a location 4 equipped with a channel 41 with branch 42 to which optical fibers 43 arrive from the light source not shown.

 The light source could also be placed in the vicinity of the branch 42 or in place of the latter. The choice of the location of the light source depends on the nature of the product 1 and its accessibility. The light source must indeed be accessible and can be replaced. Furthermore, in many cases, the light source must be able to power several products 1 to facilitate the problems of management and maintenance of the equipment, in the case of road signs, bollards or lane dividers, even elements of urban furniture or lighting or illumination of facades in the case of a construction element provided with optical fibers, for example a cornice.

 FIG. 2 shows another example of product 1A according to the invention in the form of a cornice or concrete building element, prefabricated, provided with an insert 3 comprising a base element 31A and branches 32A, 33A, 34A.

 The basic element 31A is of elongated, straight or curved shape depending on the shape of the product 1A. The branches 32A, 33A, 34A coming from the basic element reach the facets 121A, 122A, 123A of the product to form light points IIIA, 112A, 113A similar to the points 11 of the product 1 (fig. 1).

 The number and the distribution of the branches of the insert 3A are freely chosen according to the nature of the product 1A or of its destination.

 Figure 3 is a schematic top view of an elongated product, for example straight like product 1A (Fig. 2); it shows the arrangement of the insert 3A with its basic element 31A and the branches 32A.

 The basic element 31A contains a bundle of optical fibers 311A grouping the fibers 312A integrated in the branches 32A and forming the light points lîlA of the facet 121A (FIG. 2 shows the other light points 112A, 113A at the facets 122A, 123A).

 The basic structure of the concrete products with light points according to FIGS. 1, 2, 3 is the same and as will be described later, their production involves the same process an insert formed of a basic element provided with branches incorporating fibers optics which arrive at least in the vicinity of the free ends of the branches. This insert is itself embedded in a mass of concrete or similar material constituting the body of the product.

 The method of manufacturing a concrete product according to the invention will be described below with the aid of FIGS. 5 to 10 in the case of a product in the form of a terminal, that is to say with symmetry of revolution. The process applies under the same conditions to any product of elongated shape, of constant or variable section, curved or straight.

 According to FIG. 4, the product 1 of FIG. 1, of frustoconical shape, is produced by molding in the inverted position in a mold 6 (fig. 4) to give the appropriate finish to the visible upper part.

 The insert 3 is produced beforehand by molding, integrating the optical fibers which will exit from the insert in the form of the beam 312 (FIG. 1).

 It is also possible to stop the fibers at the surface of the insert and to feed the fibers by applying against them an optical connector connected to a fiber or a supply bundle.

 The insert 3 / tube 34 assembly is pressed into the mold so that the ends of the branches 32 are properly applied against the interior surface of the mold 6.

 In the case of an insert 3 with a bundle of fibers 312 emerging therefrom, this bundle is grouped in the tube 34.

 The upper part of the tube 34 arriving above the future product bottom is held by a support comprising a cylindrical shim 71, for example engaged in the tube 34. This shim 71 is held by spokes 72 bearing against the interior wall of the mold 6 A spring 73 preferably presses via a ring 74 on the top of the tube 34 to exert a prestress on the insert 3 for the purpose indicated.

 When the above assembly is in place, the concrete can be poured into the space between the mold 6 and the tube 34 at a height corresponding to that of the product to be produced.

 As soon as the concrete has sufficiently set, the product can be extracted from the mold 6 while still leaving the tube 34 there. This allows the mold 6 to be reused very quickly.

 The recovery of the tube 34 is done after a certain drying time.

 Figures 5 to 8 give different details of the insert 3 of the product 1.

 The axial section view of FIG. 5 shows the insert 3, its base element 31 (hub) and its branches 32. The upper part 33 of the hub 3 is threaded to receive the tube 34 (fig. 4). It could also be smooth and receive the tube 34 by simple fitting.

 The insert 3 (FIG. 5) comprises a pad 35 for optical connection into which the fibers 311 of the branches 32 arrive; the fibers stop at the surface of the pad or in the pad which then constitutes the light input and distribution manifold.

 Figure 6 is a partial top view of the insert 3 showing its base element (hub) 31 and its branches 32. To maintain the spacing of the branches 32 it may be advantageous in some cases to bring them close to their ends by spacers 36, however leaving the heads 321 of the branches 32 protrude so that the spacers 36 are well embedded in the concrete and do not appear or weaken this part of the product.

 FIG. 7 is an enlarged view of detail VII of FIG. 5 showing a particular shape of the end 321 of the branch 32. This end does not cover the part 322, the end of the fiber 311. This part 322, produced by molding, can have practically any shape as a function of the direction to be given to the light beam to be emitted and to the solid angle of this beam. This part 322 can constitute a convex or concave lens.

It advantageously exists to protect the emission face 313 of the fiber 311.

 Figure 8 is a section of a branch 32 showing a T-shape with the fiber 311 placed at the intersection of the arms.

 FIGS. 9 and 10 show by partial diagrams the installation of the insert 3 then the connection of the optical fibers, after the pouring of the concrete and the release of the tube 34.

 Thus, Figure 9 shows the insert 3 on which is located the tube 34 for the establishment in the mold.

 FIG. 10 shows the insert 3 integrated into the concrete of the body of the product 21, after extraction of the tube 34 and connection of the optical power supply in the case of an insert 3 without exit of the fiber bundle. The fibers 311 stop at the surface of the pad 35 for optical connection. This pad 35 appears free in the reservation 13 of the body of the product 1.

 For the connection of the supply harness 8, it is applied firmly against the free face of the stud 35 by a cap nut 37 covering the base element 31 by being screwed on the one hand on the thread 33 of this element 31 in place of the tube 34 by the threaded part of its outer rim 371, thereby pressing its inner rim 372 on a flange 81 of the bundle 8 to make the optical contact.

 As already indicated, the example of this product with circular symmetry and its manufacturing process can be extrapolated very easily to apply to any form of product.

 Finally, it should be noted that Figures 9 and 10 show the insert 3 and the product 1 in the inverted position. This position is advantageous both for molding and drying the product and for extracting the tube 34 and making the optical connection.

Claims (8)

CLAIMS 10) Concrete product such as road signs, bollards, street furniture, or construction elements equipped with lighting and light signaling signals with optical fibers supplied from a centralized light source, - fibers optics being at least partially integrated into the body of the concrete product at the time of its manufacture to form luminous spots on the surface of the body, characterized in that it comprises an insert (3, 3A) with branches (32, 32A , 33A, 34A) coming from a basic element (31, 31A) arriving directly at the surface (12, 121A, 122A, 123A) of the concrete body (1, 1A) at the location of the light points (11, IIIA, 112A, 113A) of the optical fibers (311, 311A) housed in the branches and arriving at the outer surface of the branches to form the light spots. 20) Product according to claim 1 characterized in that the basic element of the insert (3) is a hub (31) from which branches (32) in the form of spokes in which the optical fibers are integrated. 30) Product according to claim 2, characterized in that the branches (32) are located in the same plane. 40) Product according to claim 1, characterized in that the insert (3A) comprises a basic element (31A) in the form of a bar from which branches (32A, 33A, 34A) spread out in several layers around the 'basic element (31A) and arriving at the facets (121A, 122A, 123A) of the product (1A). 50) Product according to claim 1, characterized in that it comprises several inserts. 60) Product according to claim 1, characterized in that the material of the insert (3, 3A) is transparent and the ends (322) of the branches (32) cover the emission surfaces (313) of the fibers (311) by forming optical elements defining the shape of the emission beam. 70) Means for producing concrete products equipped with lighting and light signaling elements with optical fibers, according to any one of the preceding claims, characterized in that it consists of a mold (6) defining the external shape of the product to be obtained receiving the insert (3), the external surfaces of the branches (32) of which are applied against the corresponding surface of the mold and of a reservation tube (34) provided in the upper part with a positioning support (7) of the insert (3), outside the volume which will be occupied by the poured concrete. 80) Means according to claim 7, characterized in that the insert (3) has a receiving surface (33) on which engages the end of the tube (34). 90) Means according to claim 8, characterized in that the receiving surface (33) is a thread capable of receiving a connection means for the optical supply of the pad (35) of the insert.  10) A method of manufacturing concrete products according to any one of claims 1 to 6, using a means according to claims 7 to 9, characterized in that the mold is placed in the inverted position relative to the normal position of the product, the insert (s) are installed in the mold, these inserts having been previously molded with optical fibers arriving at the outer surface of the branches, the insert is fixed in the mold and the concrete is poured, then it is removed from the mold after a short period, without waiting for the concrete to finish drying.