FR3020308B1 - SANDWICH PANEL COMPRISING TWO ABSORPTION LAYERS FOR MECHANICAL DEFORMATIONS - Google Patents

Abstract

Sandwich panel (10) having a first plate (14) and a second plate (16), an insulation layer (12) disposed between the first and second plates, a first mechanical deformation absorption layer (20), separate the insulation layer (12) disposed between the insulation layer (12) and the first plate (14), and a second mechanical deformation absorption layer (20 '), distinct from the insulation layer (12) disposed between the insulation layer (12) and the second plate (16).

Description

FIELD OF THE INVENTION

The present invention relates to the field of building materials and more particularly to insulation materials including but not limited to homes, offices and industrial premises. The present invention relates more particularly to a sandwich panel

STATE OF THE PRIOR ART

FR 2 942 742 discloses a sandwich panel comprising a first plate and a second plate, an insulation layer disposed between the first and second plates, a single mechanical deformation absorption layer, distinct from the insulation layer, this single mechanical deformation absorption layer being disposed between the insulation layer and the first plate.

Such a sandwich panel is traditionally used to thermally insulate an entrance door to a living room or industrial building, this door separating the interior of the premises from the outside.

In a known manner, the insulation layer may consist of a foam layer or any other insulating material, while the first and second plates are generally made of aluminum or PVC.

Such a sandwich panel has been designed to avoid bending deformations of the sandwich panel itself when there is a significant temperature difference between the interior of the room and the outside. Indeed, this difference in temperature is reflected on the first and second plates and the expansion phenomenon of each of the plates tends to deform the structure of the door. For example, in winter, the temperature of the plate which is turned towards the outside of the room, for example the first plate, being substantially lower than the temperature of the plate which is turned towards the interior of the room, the sandwich panel tends to to deform due to the mechanical stresses induced by thermal expansion of the material constituting the first and second plates. The mechanical deformation absorbing layer is provided to absorb the differential thermal expansion of the plates, so that the panel does not deform, or in an acceptable manner.

However, this known sandwich panel does not provide complete satisfaction flexural deformations of the panel is not always avoided.

These flexural deformations are generally concave or convex, depending on the plate considered. Moreover, such deformation can damage the door in which the sandwich panel is installed or, at the very least, make it more difficult to open or close the door due to its deformation with respect to the door frame. Finally, this deformation can affect the aesthetics of the door.

PRESENTATION OF THE INVENTION

This presentation concerns a sandwich panel.

One embodiment relates to a sandwich panel having a first plate and a second plate, an insulation layer disposed between the first and second plates, a first mechanical deformation absorption layer, distinct from the insulation layer, disposed between the insulation layer and the first plate, and a second mechanical deformation absorption layer, distinct from the insulation layer, disposed between the insulation layer and the second plate.

The inventors have found that this sandwich panel does not deform, or in an acceptable manner, and in all cases considered, and has an improved behavior compared to the aforementioned sandwich panel of the state of the art.

The fact that this sandwich panel does not deform, or in an acceptable manner, while the sandwich panel of the state of the art is deformed in a troublesome way in some cases is explained by the following phenomenon identified by the inventors: not only the deformations appear as a function of the temperature differential between the first and the second plate, but the deformation for a given temperature differential is also a function of the temperature range considered.

In particular, the behavior of the mechanical deformation absorption layers (hereinafter "absorption layer") is a function of the temperature to which it is subjected. Indeed, an absorption layer is generally made of polymeric material (ie plastic), for example polypropylene, the rigidity of such a layer varies greatly depending on the temperature, especially on the temperature ranges most often encountered in the use of sandwich panels, for example between -30 ° C and + 80 ° C. Thus, the lower the temperature at which the absorption layer is subjected, the more its rigidity increases while at most the temperature at which the absorption layer is subjected is high, the more its rigidity decreases.

Thus, in the sandwich panel of the state of the art, the first plate, generally much stiffer than the first absorption layer, which is itself in general more rigid than the insulation layer, imposes its behavior. mechanical to the assembly formed by the first plate, the first absorption layer and the insulation layer when the first absorption layer stiffens in low temperatures is no longer able to absorb the deformations of the sandwich panel due to the thermal expansion differential between the first and second plates (a temperature differential being applied to the first plate and the second plate).

By arranging a second absorption layer between the insulating layer and the second plate, the assembly formed by the first plate, the first absorption layer and the insulation layer is mechanically etched on the one hand, and the second plate on the other hand. When the first wall is subjected to a low temperature, for example a temperature below -20 ° C while the second wall is subjected to a higher temperature, for example the temperature of a room, for example + 25 ° C, it is mainly the second absorption layer which absorbs the differential of thermal deformations between the assembly formed by the first plate, the first absorption layer and the insulation layer on the one hand and the second plate of other on the other hand, so that the sandwich panel does not deform, or in an acceptable manner. This case is encountered for example in winter, the first plate being oriented towards the outside of the room while the second plate is oriented towards the interior of the room, the room being heated.

Conversely, when the first wall is subjected to a high temperature, for example a temperature above + 75 ° C while the second wall is subjected to a lower temperature, for example the temperature of a room, for example + 25 ° C, it is mainly the first absorption layer that absorbs the differential of thermal deformations between the assembly formed by the second plate, the second absorption layer and the insulation layer on the one hand and the first plate of on the other hand, so that the sandwich panel does not deform, or in an acceptable manner. This case is encountered for example in summer, the first plate being oriented towards the outside of the room while the second plate is oriented towards the interior of the room, the room being air-conditioned.

Thus, the inventors have highlighted and explained why the sandwich panel of the state of the art does not give total satisfaction, and found an economical and reliable solution to this problem.

It should be noted that, in general, the insulation layer is a thermal and / or acoustic insulation layer, this layer possibly itself being formed of a single layer or of several sub-layers, for example one or more sub-layers. thermal insulation layers, one or more thermal insulation sub-layers and one or more mechanical reinforcing sub-layers.

It will of course be understood that the first plate is distinct from the first absorption layer while the second plate is distinct from the second absorption layer. In other words, the first plate, the second plate, the first absorption layer, the second absorption layer and the insulation layer form five distinct layers that can be directly assembled together, or via one or several intermediate layer (s).

In some embodiments, the first plate and the second mechanical deformation absorption layer are similar.

This reduces manufacturing costs, on the one hand from the point of view of the supply of components and on the other hand from the point of view of the facilitated labor, and an easier implementation of the sandwich panel.

In some embodiments, the first mechanical deformation absorption layer is bonded to the insulation layer and the first plate and / or the second mechanical deformation absorption layer is bonded to the insulation layer and to the the second plate.

It is understood that either only the first absorption layer is glued, or only the second absorption layer is glued, or the two absorption layers are glued.

Thanks to this collage assembly, the deformation stresses experienced by the first / second plate are transmitted directly to the first / second absorption layer, thus ensuring internal decoupling of the various satisfactory layers.

In some embodiments, the first mechanical deformation absorption layer and / or the second mechanical deformation absorption layer is constituted by a plate provided with a plurality of grooves machined on a fraction of the thickness of said plate. .

It is understood that either only the first absorption layer, or only the second absorption layer or the two absorption layers are respectively constituted by a plate provided with a plurality of grooves machined on a fraction of the thickness of said plate.

The presence of the grooves thus defines patterns on the plate, each pattern being free to move in their plane, as a result of which, each pattern is deformable independently of the others.

It follows that the patterns are able to absorb deformations by expansion of the first / second plate.

In some embodiments, the grooves include first and second sets of orthogonal grooves therebetween to define pavers.

The aforementioned reasons thus have the shape of square or rectangular blocks. These patterns are easy to machine, and are particularly effective at absorbing bending deformations of a door when the grooves are substantially parallel to the edges of the door.

In some embodiments, the insulation layer, also called insulating core, does not have a groove so as not to reduce its insulating capacity.

In other words, the deformations are essentially taken up by the first / second deformation absorption layer and not by the insulation layer.

In some embodiments, the grooves of the first mechanical deformation absorption layer are oriented (ie open) towards the first plate while the grooves of the second mechanical deformation absorption layer are oriented (ie open) towards the second plate.

The inventors have surprisingly noticed that this configuration makes it possible to appreciably improve the absorption of the deformations of the first and second plates. Indeed, the inventors have noticed that by orienting the grooves of the absorption layers to the adjacent plate is optimized decoupling of each plate relative to the internal structure of the panel. Moreover, this configuration makes it possible to manufacture a symmetrical sandwich panel, so that its implementation is facilitated.

In certain embodiments, the first mechanical deformation absorption layer and / or the second mechanical deformation absorption layer is made from a cellular material, for example of the cellular polypropylene type.

It will of course be understood that only the first absorption layer is made of cellular material, or that only the second absorption layer is made of cellular material, or that these two absorption layers are made of cellular material.

In some embodiments, the cells extend in a plane parallel to the plates, transversely to the sandwich panel.

In some embodiments, the first plate and / or the second plate is made of aluminum, PVC, steel or fiberglass composite material.

It will of course be understood that only the first plate is made of aluminum, PVC, steel or composite material based on glass fibers, or that only the second plate is made of aluminum, PVC, steel or composite material with fiberglass base, or that the two plates are made of aluminum, PVC, steel or composite material based on glass fibers. According to one variant, the first and the second plates are both made of aluminum, both of PVC, both of steel, or both of composite material based on glass fibers. Aluminum, PVC (or polyvinyl chloride), steel or a fiberglass composite material are particularly suitable materials for the manufacture of plates.

In some embodiments, the first mechanical deformation absorption layer and / or the second mechanical deformation absorption layer is made of polypropylene.

It will of course be understood that only the first absorption layer is made of polypropylene, or that only the second absorption layer is made of polypropylene, or that these two absorption layers are made of polypropylene.

Polypropylene (also known by the acronym "PP"), is a particularly suitable material for the manufacture of mechanical deformation absorption layers.

In certain embodiments, the sandwich panel strictly comprises two mechanical deformation absorption layers, namely the first mechanical deformation absorption layer and the second mechanical deformation absorption layer.

Such a sandwich panel structure has an optimum efficiency / manufacturing cost ratio.

This presentation also relates to a door for a room.

One embodiment relates to a door for a room having a sandwich panel according to any one of the embodiments described herein.

In some embodiments, the first plate is intended to be turned towards the outside of the room, while the second plate is intended to be turned towards the interior of the room.

In some embodiments, the first mechanical deformation absorption layer and / or the second mechanical deformation absorption layer is made from a cellular material, and has a plurality of horizontally extending cells.

It should of course be understood that only the first absorption layer is made of cellular material, a plurality of cells of which extends horizontally, or that only the second absorption layer is made of cellular material, a plurality of cells of which extends horizontally, or that these two absorption layers are of cellular material of which a plurality of cells extends horizontally.

BRIEF DESCRIPTION OF THE DRAWINGS The invention and its advantages will be better understood on reading the detailed description given below of various embodiments of the invention given as non-limiting examples. This description refers to the pages of appended figures, in which: - Figure 1 shows a partial sectional view of the sandwich panel, taken in a plane orthogonal to said panel; FIG. 2 is a partial exploded perspective view of the sandwich panel without the first plate, showing the grooves of the first mechanical deformation absorption layer; and

- Figure 3 illustrates a door comprising the sandwich panel. DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Figures 1 and 2 show the constituent elements of a sandwich panel 10 according to the present invention. The sandwich panel 10 has a parallelepipedal shape having a thickness E and longitudinal and transverse dimensions. It is understood that the section of Figure 1 is taken in a plane orthogonal to the surface of the panel 10, so that the constituent elements of the sandwich panel are seen here according to the thickness E of said panel.

Preferably, the thickness E of the sandwich panel 10 is between 30 and 120 millimeters, but not necessarily.

The sandwich panel 10 of this example is an insulating panel. Thus it has an insulating layer 12, in this case a layer of insulating foam known elsewhere, which is sandwiched between a first plate 14, also called first facing, and a second plate 16, also called second siding.

The first and second plates 14, 16 are flat plates or, in a variant not shown, plates which have reliefs, which are fine with respect to the total thickness E of the sandwich panel 10.

In addition, the first and second plates 14, 16 are in this example made of aluminum. However, it is possible to choose another material depending on the destination of the sandwich panel 10.

The sandwich panel 10 comprises a first mechanical deformation absorption layer 20, distinct from the insulation layer 12, disposed between the insulation layer 12 and the first plate 14. The sandwich panel 10 also comprises a second layer of absorption of mechanical deformations 20 ', distinct from the insulation layer 12, arranged between the insulation layer 12 and the first plate 14.

The first and second absorption layers 20 and 20 'are similar, and mounted back-to-back on the insulation layer 12. Thus, unless otherwise indicated, the description of the characteristics of the first absorption layer 20 also applies for the second absorption layer 20 '. For their maintenance, the first absorption layer 20 is bonded to the insulation layer 12 and the first plate 14 while the second absorption layer 20 'is bonded to the insulation layer 12 and the second plate 16.

As seen in FIG. 1, the first absorption layer 20 is substantially thinner than the insulation layer 12. In fact, the thickness Ec of the first absorption layer 20 is preferably comprised, but not necessarily, between 3 and 15 millimeters, while the thickness of the insulation layer 12 is preferably, but not necessarily, between 10 and 115 millimeters. It is the same for the second absorption layer 20 '.

In this example, the first and second absorption layers 20 and 20 'are made of cellular polypropylene.

As seen in FIG. 2, the first absorption layer 20 is constituted by a plate provided with a plurality of orthogonal grooves 22 machined over a fraction of the thickness Ec of said plate. It is the same for the second absorption layer 20 '.

Preferably, but not necessarily, the depth of the grooves 22 is between 2 and 12 millimeters, while they have a width of between 1 and 5 millimeters.

Furthermore, the grooves 22 of the first absorption layer 20 are arranged to open towards the first plate 14 while the grooves 22 of the second absorption layer 20 'are arranged so as to open towards the second plate 16. In other words, the grooves of the first absorption layer 20 are oriented towards the first plate 14 while the grooves of the second absorption layer 20 'are oriented towards the second plate 16.

As seen in Figure 2, the grooves 22 comprise first and second sets of grooves 22a, 22b orthogonal to each other, so as to define the blocks 24, 26 the latter being mechanically decoupled from each other.

In other words, each block 24, 26 is carried by a wall S and delimited by two grooves of the first series 22a and two grooves of the second series 22b.

In the present case, the first and second absorption layers 20 and 20 'comprise square blocks 24 as well as rectangular blocks 26. In this example, the first and second absorption layers 20 and 20' are composed of five columns longitudinal, namely a central column of rectangular blocks 26 bordered on each side by two columns of square blocks 24.

Furthermore, the first and second layers 20 and 20 'are made from a cellular material, so that these layers 20 and 20' have a plurality of cavities 28 extending in the plane of the sandwich panel 10. Preferably, but not necessarily, these cells are arranged to extend parallel to the axis about which the sandwich panel tends to deform.

FIG. 3 shows a room entrance door 30 comprising the sandwich panel 10. The sandwich panel 10 is mounted such that the first plate 14 is turned towards the outside of the room, while the second plate 14 16 is facing the interior of the room. In addition, the cells 28 extend in a horizontal direction, that is to say perpendicular to the height of the door.

When there is a substantial temperature difference between the first plate 14 and the second plate 16, for example when the outside temperature is substantially lower or greater than the temperature of the interior of the room, the first plate 14 tends to distort due to thermal expansion.

The first absorption layer 20 being bonded to the first plate 14, and the grooves being preferably turned towards said first plate 14, it is understood that the blocks 24, 26 of the first absorption layer 20 are themselves bonded to the first plate 14.

It follows that the mechanical stresses undergone by the first plate 14, because of the expansion are transmitted to the blocks 24, 26 of the first absorption layer 20, as a result of which they tend to deform. The blocks 24, 26 being separated from each other by the ribs 22, it is understood that each block 24, 26 is free to deform or move relative to neighboring blocks without transmitting mechanical stresses.

In other words, each pad 24, 26 deforming independently of the others, it absorbs locally the deformation undergone by the surface portion of the first plate 14 to which it is bonded.

As a result, the wall S of the absorption layer 20 which carries the blocks 24, 26 is deformed very little.

As a result, few mechanical stresses are transmitted to the insulation layer 12, so that the latter does not deform or very little. All the more reason, the second plate 16 does not deform either.

When the outside temperature is particularly low, for example when the outside temperature is below -20 ° C, the rigidity of the first absorption layer 20, which in this example is made of polypropylene, increases significantly so that the pavers 24 , 26 of the first absorption layer 20 are no longer able to deform sufficiently.

In this case, the rigidity of the first plate 14, which in this example is aluminum, is greater than the rigidity of the first absorption layer 20 and the insulation layer 12, which in this example is made of foam insulating, the thermal expansion of the first plate 14 also deforms the first absorption layer 20 as well as the insulation layer 12. The second absorption layer 20 'being bonded to the insulation layer 12, the deformations induced by the thermal expansion of the first plate 14 also impacts the wall S of the second absorption layer 20 '. However, thanks to the mechanical independence of the blocks 24 and 26 relative to each other, the deformations undergone by the wall S of the second absorption layer 20 'generate very little or no mechanical stress at all. in the second plate 16 so that the second plate 16 deforms very little or not at all.

The inventors have noticed that in the latter case, the absorption achieved by the second absorption layer 20 'is more efficient when the grooves 22 are oriented towards the second plate 16 (ie the wall S of the second absorption layer 20 'side insulation layer 12) only when the grooves 22 are oriented towards the insulation layer 12 (ie wall S of the second absorption layer 20' second side plate 16).

It is therefore understood that, depending on the case, the deformations experienced by the first plate 14 are substantially taken up by the first absorption layer 20 or the second absorption layer 20 ', and are not transmitted to the second plate 16 as a result of which, the door 30 comprising the panel 10 deforms substantially less than the doors provided with sandwich panels of the state of the art, and in most cases encountered in the use of such doors .

In the present example, the structure of the sandwich panel 10 being symmetrical in the direction of its thickness E, it is understood that the behavior of the door 30 is identical to that described above when considering the impact of the second plate dilations. 16 on the first plate 14, the second plate 16 and the second absorption layer 20 'then behaving respectively as the first plate 14 and the first absorption layer 20 as described above, and vice versa.

Although the present invention has been described with reference to specific exemplary embodiments, it is obvious that modifications and changes can be made to these examples without departing from the general scope of the invention as defined by the claims. In particular, individual features of the various embodiments illustrated / mentioned can be combined in additional embodiments. Therefore, the description and drawings should be considered in an illustrative rather than restrictive sense.

Claims (9)

A sandwich panel (10) having a first plate (14) and a second plate (16), an insulation layer (12) disposed between the first and second plates, a first mechanical deformation absorption layer (20). , distinct from the insulation layer (12), disposed between the insulation layer (12) and the first plate (14), said sandwich panel being characterized in that it comprises a second mechanical deformation absorption layer (203), separate from the insulation layer (12), disposed between the insulation layer (12) and the second plate (16), wherein the first mechanical deformation absorption layer (20) and / or the second mechanical deformation absorption layer (203 is constituted by a plate provided with a plurality of grooves (22, 22a, 22b) machined on a fraction of the thickness of said plate. The sandwich panel according to claim 1, wherein the first mechanical deformation absorbing layer (20) is adhered to the insulation layer (12) and the first plate (14) and / or the second layer of absorption of mechanical deformations (209 is bonded to the insulation layer (12) and to the second plate (14). 3. A sandwich panel according to claim 1 or 2, wherein the grooves (22) comprise first and second sets of grooves (22a, 22b) orthogonal to each other, so as to define pavers (24, 26). A sandwich panel according to any one of claims 1 to 3, wherein the grooves (22, 22a, 22b) of the first mechanical deformation absorbing layer (20) are oriented towards the first plate (14) while the grooves (22, 22a, 22b) of the second mechanical deformation absorbing layer (209 are oriented towards the second plate (16). A sandwich panel according to any one of claims 1 to 4, wherein the first mechanical deformation absorption layer (20) and / or the second mechanical deformation absorption layer (203 is made from a cellular material. A sandwich panel according to any one of claims 1 to 5, wherein the first plate (14) and / or the second plate (16) is made of aluminum, PVC, steel or fiber composite material. glass. A sandwich panel according to any one of claims 1 to 6, wherein the first mechanical deformation absorbing layer (20) and / or the second mechanical deformation absorbing layer (20 ') is made of polypropylene. 8. Door (30) for a room comprising a sandwich panel (10) according to any one of claims 1 to 7. 9. Door according to claim 8, wherein the first mechanical deformation absorption layer (20) and / or the second mechanical deformation absorption layer (209 is made from a cellular material, and has a plurality of cells (26) extending horizontally.