PANEL FOR AIR-CONDITIONING DUCTS

Abstract

A panel for self-supporting ducts, in particular air-conditioning ducts, made up of a core of mineral wool, covered on its external face with an exterior covering joined to the external surface of the core, the exterior covering including a sheet of aluminum and the sheet of aluminum being the outermost sheet of the exterior stack, wherein the sheet of aluminum exhibits, at least on its outwardly exposed face, diffuse reflection greater than its specular reflection.

Claims

1. A panel fora self-supporting duct made up of a mineral wool core, covered on its external face with an exterior covering joined to the external surface of the mineral wool core, said exterior covering comprising a sheet of aluminum and said sheet of aluminum being the outermost sheet of the exterior covering, wherein said sheet of aluminum has, at least on its outwardly exposed face, a diffuse reflection greater than its specular reflection.

2. The panel according to claim 1, wherein the diffuse reflection of said outwardly exposed face of the sheet of aluminum is at least twice as great as its specular reflection.

3. The panel according to claim 1, wherein the diffuse reflection of said outwardly exposed face of the sheet of aluminum is greater than 50%.

4. The panel according to claim 1, wherein the specular reflection of said outwardly exposed face of the sheet of aluminum is less than 30%.

5. The panel according to claim 1, wherein a roughness parameter Sz of the outwardly exposed face of the sheet of aluminum, as measured according to the NF ISO 25178 standard, is greater than 20 micrometers.

6. The panel according to claim 1, wherein a roughness parameter SSk of the outwardly exposed face of the sheet of aluminum, as measured according to the NF ISO 25178 standard, is greater than 0.1.

7. The panel according to claim 1, wherein the other face of the sheet of aluminum has a specular reflection greater than its diffuse reflection.

8. The panel according to claim 1, wherein the other face of the sheet of aluminum has a specular reflection less than its diffuse reflection.

9. The panel according to claim 1, wherein the mineral wool core is covered on its interior face with an inner covering connected to the interior surface of the core and comprising an exterior sheet of aluminum, the sheet of aluminum having, on its face furthest from said core, a diffuse reflection greater than its specular reflection.

10. The panel according to claim 1, wherein the exterior covering consists of said sheet of aluminum.

11. The panel according to claim 1, wherein said exterior covering comprises a sheet of kraft paper arranged below said sheet of aluminum.

12. The panel according to claim 1, wherein the outer surface of the mineral wool core further comprises a mat of fiberglass or synthetic fibers, said mat being bonded to the mineral wool core by the binder used for the crosslinking of the mineral fibers constituting said mineral wool core, so that the panel comprises, from the external surface of the mineral wool core: said mat of fibers of fiberglass or of synthetic fibers, said exterior covering.

13. The panel according to claim 1, wherein the exterior covering is covered with an anti-UV protective film.

14. The panel according to claim 1, wherein the panel terminates at its end in an edge to be interconnected.

15. The panel according to claim 1, wherein the covering of the panel is extended into a flap so that, in an assembly situation with another module, it partially overlaps the covering of said module.

16. A self-supporting duct manufactured from panels according to claim 1.

17. A method comprising providing one or more panels according to claim 1 for the manufacture of a self-supporting duct.

18. The panel according to claim 1, wherein the self-supporting duct is an air-conditioning duct.

19. The panel according to claim 3, wherein the diffuse reflection of said outwardly exposed face of the sheet of aluminum is greater than 70%.

20. The panel according to claim 4, wherein the specular reflection of said outwardly exposed face of the sheet of aluminum is less than 20%.

Description

[0050] To complete the preceding description of the present invention, and help to better understand the characteristics thereof, a preferred (but not limited) example of its practical embodiment is described below, in connection with the set of appended drawings, as an integral part of said description where, by way of non-limiting illustration, we have shown the following:

[0051] FIG. 1 shows a representation in perspective of a panel from which a module is obtained to constitute external air conditioning ducts, all achieved in accordance with the object of the present invention.

[0052] FIG. 2 shows a perspective view of the connection of two contiguous modules within a self-supporting duct according to the invention.

[0053] FIG. 3 shows an enlarged detail view of a first alternative embodiment of the connector shown in FIG. 2.

[0054] FIG. 4 schematically shows an enlarged detail view of a second alternative embodiment of the connector shown in FIG. 2.

[0055] FIG. 5 shows an exploded view of all of the elements constituting the panel and the duct according to one embodiment of the invention.

[0056] FIG. 6 illustrates the method used to measure the reflections according to the invention.

[0057] As can be seen in the aforementioned figures, the panel (1-1′) according to the invention is formed from a mineral wool core (2-2′) (glass wool or rock wool) or similar, which on its face considered external is covered with an exterior covering (3-3′) allowing it to be mechanically and chemically resistant.

[0058] Within the meaning of the present invention, the terms “external”, “exterior”, “internal” and “interior” refer to the respective positions of the different components of the panel in the final duct, unless otherwise indicated.

[0059] FIGS. 1 to 4 describe the assembly and fitting of the panels according to the invention and such as, for example, illustrated by FIG. 5 in order to obtain self-supporting ducts. From this structure and with the appropriate cutting and folding tools, it is possible according to the invention to form, with a single type of panel, a multitude of types of types, configurations and different geometries, and this quickly and simply, as is in particular described in the publication EP 1-532-391 A1.

[0060] As regards the mode of connection between modules within the self-supporting ducts, provision may be made for the panels to terminate at their ends by edges to be interconnected, such as those shown in detail in FIGS. 3 and 4, so that preferably the multilayer exterior covering 3 is extended slightly into a flap 8 which partially overlaps the covering 3′ of the contiguous module, thus preventing the water/moisture inlet. It is possible to use a tape of the same material as the covering.

[0061] This interconnection may be straight, as shown in FIG. 3, or oblique, as shown in FIG. 4, without affecting the essence of the invention.

[0062] As described below in greater detail in FIG. 5, according to one possible embodiment, the exterior covering 3 comprises a layer of kraft paper 6 covered with an exterior sheet of aluminum 4, the two elements preferably being bonded by an adhesive, said sheet of aluminum also being able to be reinforced by a mesh of reinforcing glass fibers 9 (a scrim layer) in order to form an FSK (foil-scrim-kraft) complex.

[0063] According to another configuration according to the invention, the coverings according to the invention may consist only of an aluminum sheet 4 preferably reinforced by mesh of reinforcing fibers 9, preferably glass fibers.

[0064] The assembly can be protected against ultraviolet rays by an additional film known to this end, as previously described (not shown in FIG. 5)

[0065] On the so-called interior face of the duct (with reference to its final position in the duct), the central core is covered, with a glass fabric 7, or with a single sheet of aluminum 5, optionally reinforced by a reinforcing mesh 9, one or more kraft paper-aluminum sheet combinations.

[0066] Optionally, a glass fabric or a glass mat 7 can also be attached to said core by means of an adhesive (not shown in the figures) or alternatively by the binder uniting the fibers of the mineral core to further improve the mechanical content of the duct, on one face or both faces of said core 2. In FIG. 5, the central core 2 made of mineral wool is bordered on its external face of a glass fiber fabric 7, in particular an Neto® fabric from the applicant company.

[0067] The opposite surface of the central core 2 can also be reinforced by means of another fiberglass mat 7 (not shown). According to a preferred embodiment, the mat or the glass fabric 7 is deposited on the external face of the core during the manufacture of the dense mat of mineral fibers, before the binder passes through the curing oven. In this way, a reinforcing mat is obtained that is integrated into the surface of the core made of mineral wool, that is to say bonded thereto by the same binder uniting the mineral fibers of the core, the reinforcement of which is thus improved.

[0068] A panel or duct according to the invention may of course comprise other additional elements, in particular additional layers and/or sheets entering the composition of the exterior covering 3.

[0069] On the external face of the central core 2, that is to say on the outwardly-turned face once the self-supporting duct is manufactured from the panel, the multilayer exterior covering 3 is positioned and bonded to the surface of the core, where appropriate via the reinforcement mat 7, via a layer of glue (not shown). This layer of glue is preferentially a glue of polyurethane but may also be chosen from adhesives made of Low-Density polyethylene (LDPE), hot-melt adhesives or water-based adhesives.

[0070] According to another possible embodiment, a layer of plastic material such as polyester then the UV protective film can first be placed above the sheet of aluminum 4, in particular of the type described above.

[0071] According to another configuration not described in FIG. 5 but included in the context of the present invention, the protective covering can comprise several aluminum films, for example two aluminum films, separated from one another by layers of plastic such as polyester.

[0072] According to the invention, the layers of plastic material are directly bonded to the film or to the aluminum films or alternatively via any adhesive known in the art to allow such a metal-plastic connection (not shown in FIG. 5).

[0073] Preferably, according to the invention, the total thickness of the covering 3 is between 5 microns and 1000 microns, preferably between 50 microns and 500 microns, and very preferably between 30 and 250 microns.

[0074] According to the invention, the sheet of aluminum 4 is configured to have a diffuse reflection greater than, or even very much greater than, the specular reflection.

[0075] In Table 1 below, the values of total reflection, specular reflection and diffuse reflection of a sheet of aluminum as sold currently and of a sheet of aluminum, configured according to the present invention, were transferred to increase the specular reflection (of visible light; between 380 nm and 780 nm).

[0076] The reflections (as a percentage of the incident light) were measured using a UV-Vis-NIR Perkin Elmer Lambda 900 spectrometer equipped with an integrating sphere of 150 mm for the visible range (380 nm-780 nm) with a step of 5 nm with an integration step of 0.26 second per measurement step. It is estimated that the accuracy of the measurement is ±0.15%. The reflections are measured with an incident angle of 8° (0° being the normal).

[0077] FIG. 6 illustrates the configuration used to measure the diffuse reflection and the total reflection of the visible light. FIG. 6 schematically shows the integrating sphere.

[0078] The sphere is equipped with two ports 11 and 12 and an opening to introduce the incident beam 13 into the latter.

[0079] For the measurement of the total transmission (specular+scattering), the sample is placed on the port 11 (where the port 11 is replaced by the sample), the port 12 remaining in place (FIG. 6a). The integrating sphere thus allows the total reflection of the light by the sample.

[0080] For the measurement of the diffuse transmission, the port 11 is also replaced by the sample, but the port 12 is removed (FIG. 6b). The beam 14 resulting from the specular reflection on the sample can thus escape from the sphere without entering into the measurement obtained by the integrating sphere.

[0081] The specular reflection is obtained by subtracting the diffuse reflection from the total reflection.

TABLE-US-00001 TABLE 1 Total Diffuse Specular reflection R.sub.T* reflection R.sub.D reflection R.sub.S Sheet of aluminum 92 76 16 according to the invention Commercial sheet of 90 28 62 aluminum *R.sub.T = R.sub.D + R.sub.S

[0082] The roughness characteristics of the two sheet of aluminums were measured using a profilometer according to the NF ISO 25178 standard.

[0083] More precisely, the topography measurements were carried out using a STIL profilometer comprising an optical contactless sensor (confocal chromatic sensor). The measurement points were acquired on a square grid with a spacing of 1 μm. The images were acquired on a surface area of 5 mm×2.5 mm, avoiding printed topography lines, and then analyzed using the software MountainsMap Scanning Topography 7.4 from DigitalSurf. The surfaces were straightened with a plane and the roughness parameters finally calculated according to the NF ISO 25178 standard.

[0084] The values of the parameter Sz (which measures the maximum distance between a peak and a trough) and the parameter SSk (which measures the asymmetry (Skewess) of the surface studied) are reported in Table 2 below:

TABLE-US-00002 TABLE 2 Sz (micrometers) SSk Commercial sheet of 17 0.06 aluminum Sheet of aluminum 48 0.43 according to the invention

[0085] It was then checked that the use of an aluminum covering whose characteristics meet the present invention has the following advantages: [0086] for the installer, by reducing the reflection of the light and avoiding dangerous and uncomfortable reflections without direct exposure to light coming from the surface of the covering of the panel used. By minimizing the specular reflection in favor of a diffuse reflection, the visual comfort and visual fatigue of the installer or dazzle are improved. The safety of the installation is thus improved.

[0087] In addition, such work in a secure environment may be guaranteed regardless of the work area, in particular in any place (outside or inside), and regardless of the type of lighting (natural or artificial) and its intensity. It makes it possible in particular to work outside on sunny days, without intense reflections and by minimizing the reflection of light and heat.

[0088] It also makes it possible to improve the effectiveness of the work carried out, for example by guaranteeing greater precision in cutting, in particular if guiding lines are present on the surface of the panel to be cut out as described in publication WO 2004/001277, in particular improving the contrast between said cutting lines and the surface of the exterior aluminum covering.

[0089] The installation work is also made more efficient during cutting, by facilitating the figures of ducts both on the interior face if that face is also covered with a sheet of aluminum according to the invention whose diffuse reflection is greater than its specular reflection, in particular longitudinal cuts than on the external face of the panels, for the assembly of the figures.

[0090] The use of a sheet of aluminum according to the invention in the exterior covering also makes it possible to improve the aesthetics of the final installation since it contributes to the visual uniformity of the overall installation independently of the lighting (outside or inside) and of its intensity.