Profiled metallic sheet for a sandwich panel

A panel extending along a longitudinal axis (X) and including a profiled metallic tray (15), a profiled metallic sheet (1) and an insulation material (16) sandwiched between the profiled metallic tray (15) and the profiled metallic sheet (1), the profiled metallic sheet (1) including in cross-section perpendicular to the longitudinal axis (X) at least a main part (3) substantially lying down in a plane P and a lateral flange (7) extending inwards from an extremity of the main part (3) and including a U-shaped bend forming a protrusion (8) extending outwards and delimited by two lateral walls (9, 10) and a free end (11), wherein the panel (2) includes a longitudinal seal (12) located in the protrusion (8) away from its free end (11) and compressed between the lateral walls (9, 10) of the protrusion (8), thus delimiting an unfillable volume (V) in the protrusion (8).

The present invention relates to a profiled metallic sheet for a sandwich panel, said panels being intended to be assembled together for the construction of building envelopes, and more particularly intended for the construction of building roofs and walls, without being limited thereto. The present invention also relates to the method for the manufacturing of such a profiled metallic sheet.

BACKGROUND

It is known to assemble sandwich panels comprising an insulation layer between an external metallic facing and an internal metallic facing to build walls or roofs.

Moreover, it is known to design the panel with a profiled metallic sheet comprising a long protrusion extending outwards from one of the longitudinal flange of the profiled metallic sheet, the opposite flange of said profiled metallic sheet comprising a step intended to cooperate with the protrusion of the profiled metallic sheet of an adjacent panel. Thanks to this design, the screws used to fasten the panels on the building structure can be hidden behind the protrusion.

It is also known to manufacture the panel by spraying liquid foam between the external and internal metallic facings, said foam thus expanding between them.

SUMMARY OF THE INVENTION

However and because of the thin transverse section of the protrusion, the foam does not correctly expand inside the protrusion. Air pockets can form and, during thermal expansion of the panel, they deform locally the protrusion. Moreover, as the adhesion promoter usually added between the metallic facings and the foam cannot penetrate inside the protrusion, the foam does not correctly adhere to the inside walls of the protrusion. This results in delamination of the foam, and thus deformation of the protrusion unavoidably occurs.

In an attempt to overcome this drawback, it is also known to stick a foam tape of rectangular section on the metallic facing ahead of its profiling so that, after profiling, the foam tape is positioned in the protrusion.

However, as the foam tape only adheres to one internal face of the protrusion, the foam can flow between the foam tape and the other internal face of the protrusion. The drawbacks described above thus also occur in that case.

An aim of the present invention is therefore to remedy the drawbacks of the prior art by providing a profiled metallic sheet and a panel which prevents the deformations of the protrusion.

For this purpose, a first subject of the present invention consists of a panel extending along a longitudinal axis (X) and comprising a profiled metallic tray (15), a profiled metallic sheet (1) and an insulation material (16) sandwiched between the profiled metallic tray (15) and the profiled metallic sheet (1), wherein said profiled metallic sheet (1) comprises in cross-section perpendicular to the longitudinal axis (X) at least:a main part (3) substantially lying down in a plane P,a first lateral flange (4) extending inwards from a first extremity of the main part (3) and comprising a step (6) extending inwards,a second lateral flange (7) extending inwards from an opposite extremity of the main part (3) and comprising a U-shaped bend forming a protrusion (8) extending outwards and delimited by two lateral walls (9,10) and a free end (11), said free end (11) being able to fit with the step (6) of the first lateral flange (4) of another adjacent panel,wherein the panel (2) comprises a longitudinal seal (12) located in the protrusion (8) away from its free end (11) and compressed between the lateral walls (9,10) of the protrusion (8), thus delimiting an unfillable volume (V) in said protrusion.

The panel according to the invention may also have the optional features listed below, considered individually or in combination:The longitudinal seal (12) is located all along the protrusion;The longitudinal seal (12) is cylindrical;The first lateral flange (4) comprises a U-shaped bend forming a lateral tenon (13) extending in parallel to plane P and outwards, and the second lateral flange (7) comprises a U-shaped bend forming a lateral mortise (14) extending in parallel to plane P and inwards, the lateral tenon (13) and the lateral mortise (14) being complementary in shape;The second lateral flange (7) comprises an inclined wall (28) linking the lateral mortise (14) and the protrusion (8), and wherein the seal is located in the protrusion (8) at the junction between said protrusion (8) and said inclined wall;The lateral walls (9,10) of the protrusion (8) extend in parallel to the plane P;the profiled metallic tray (15) comprises in cross-section perpendicular to the longitudinal axis (X) at least:a main part (17) extending in parallel to the plane P,a first lateral flange (18) extending inwards from a first extremity of the main part (17) and comprising a U-shaped bend forming a second lateral tenon (20) extending in parallel to plane P and outwards, anda second lateral flange (19) extending inwards from an opposite extremity of the main part (17) and comprising a U-shaped bend forming a second lateral mortise (21) extending in parallel to plane P and inwards, the second lateral tenon (20) and the second lateral mortise (21) being complementary in shape.

A second subject of the invention consists of a process for the manufacturing of a profiled metallic sheet (1) for a panel comprising at least the following steps:(i) profiling a metallic strip (29) along a longitudinal axis (X) so that it comprises in cross-section perpendicular to the longitudinal axis (X) at least:a main part (3) substantially lying down in a plane P,a first lateral flange (4) located at a first extremity of the main part,a second lateral flange (7) located at an opposite extremity of the main part (3) and comprising a U-shaped bend forming a protrusion (8) extending outwards and delimited by two lateral walls (9,10), an opening and a free end,(ii) providing a longitudinal seal (12) in front of the opening of the protrusion (8) opposite to its free end,(iii) inserting the seal (12) in the opening of the protrusion (8) so that said seal (12) is compressed between the lateral walls (9,10) of the protrusion (8), thus delimiting an unfillable volume (V) in said protrusion (8), and,(iv) cutting to desired length the profiled metallic strip (29) in a direction perpendicular to the longitudinal axis (X) in order to form the profiled metallic sheet.

A third subject of the invention consists of a process for the manufacturing of a panel comprising at least the following steps:(i) profiling a first metallic strip (29) along a longitudinal axis (X) so that it comprises in cross-section perpendicular to the longitudinal axis (X) at least:a main part (3) substantially lying down in a plane P,a first lateral flange (4) located at a first extremity of the main part (3), and,a second lateral flange (7) located at an opposite extremity of the main part (3) and comprising a U-shaped bend forming a protrusion (8) extending outwards and delimited by two lateral walls (9,10), an opening and a free end,(ii) Simultaneously profiling a second metallic strip along the longitudinal axis (X) so that it comprises in cross-section perpendicular to the longitudinal axis (X) at least:a main part (17) extending in parallel to plane P,a first lateral flange (18) extending inwards from a first extremity of the main part (17), anda second lateral flange (19) extending inwards from an opposite extremity of the main part,(iii) providing a longitudinal seal (12) in front of the opening of the protrusion (8) opposite to its free end,(iv) inserting the seal (12) in the opening of the protrusion (8) so that said seal (12) is compressed between the lateral walls (9,10) of the protrusion (8), thus delimiting an unfillable volume (V) in said protrusion (8),(v) Applying a foaming mixture on either the profiled first metallic strip (29) or the profiled second metallic strip,(vi) Foaming the foaming mixture between the profiled first metallic strip (29) and the profiled second metallic strip to form an insulation material (16), and(vii) cutting to desired length the assembly of the profiled metallic strip (29), the profiled second metallic strip and the insulation material (16) to form the panel.

DETAILED DESCRIPTION

It should be noted that the terms “inward”, “inwards”, “outward” and “outwards” as used in this application refer to the positions and orientations of the different constituent elements of the panel in relation to the position of the insulation material. Consequently, if an element extends inwards, it extends in the direction of the insulation panel. Similarly, if the element extends outwards, it extends in the opposite direction of the insulation panel.

It should also be noted that, to ease the description, the panels will be described in relation to their usual position on a building. Consequently, the terms “inner” and “outer” as used in this application refer to this usual position. Accordingly, the outer metallic sheet is facing the outside and the inner metallic tray is facing the inside of the building. Consequently, the inner flange refers to the flange of the inner tray and the outer flange refers to the flange of the outer sheet. Nevertheless, the panels and the corresponding assembly can be positioned upside down on a building, i.e. with the outer sheet facing the inside of the building.

It should be noted that the terms “lower”, “above”, “lowest” . . . as used in this application refer to the positions and orientations of the different constituent elements of the panel when the latter is lying on an horizontal plane.

Throughout the text, a sheet is understood to mean an element that has a flat shape, i.e., its thickness is low compared to its other dimensions. Generally speaking, its thickness is 500 to 4000 times lower than its width. The sheet may be made of a single material or a composite assembly. In the latter case, the sheet is a stack of a plurality of layers of the same material or different materials. The material in question may be, among others, a metallic material or a polymer. Steel, aluminum, copper and zinc may be cited as non-restricting examples of metallic materials. The sheet is preferably a metallic sheet. It is preferably made of previously galvanized and pre-coated steel to protect it against corrosion. The inner metallic tray and the outer metallic sheet are examples of sheets.

Within the framework of the invention, the sheet will preferably have been previously formed with the aid of any known forming method, including, by way of non-restricting examples, bending, forming, stamping and molding. In particular, the U-shaped bend described later on is an element of the panel whose manufacturing process is not limited to bending.

With reference toFIGS.1to3, the panel2of the invention has a global parallelepiped rectangular shape and extends along a longitudinal axis X. The panel2comprises four lateral sides: two opposite longitudinal sides22,23and two opposite transversal sides26extending perpendicularly to the axis X. The panel2comprises an inner face24intended for facing a building structure (not depicted), and an opposite outer face25.

The panel2further comprises an insulation material16sandwiched between a profiled metallic tray15that will be further called inner metallic tray since it forms a part of the inner face24of the panel2and a profiled metallic sheet1that will be further called outer metallic sheet since it forms a part of the outer face25of the panel2. The sides of the insulation material16thus form the longitudinal lateral edges22,23of the panel2. As it will be described later, the insulation material16is made of expanded foam, for example polyurethane foam.

The inner metallic tray15and the outer metallic sheet1are largely substantially flat. The substantially flat portion of the outer metallic sheet1lie in the plane P while the substantially flat portion of the inner metallic tray15is parallel to plane P. Flanges4,7,18,19extend from each of the lateral extremities of the flat portions along the longitudinal sides22,23of the insulation material16. The flanges4,7,18,19thus cover partially the sides22,23. The uncovered part of each longitudinal side22,23is preferably perpendicular to plane P to ease the interlocking of panels2. Those two longitudinal sides of the insulation material16are further called first22and second23longitudinal sides.

The inner metallic tray15is a metallic sheet of rectangular shape, comprising longitudinal edges and transversal edges, which has been formed at a previous stage. It comprises, in cross-section perpendicular to its longitudinal axis X, a main part further called inner central part17and two lateral flanges further called first and second inner flanges18,19and extending inwards from each extremity of the inner central part17. The inner central part17substantially lies down flat in a plane parallel to plane P. According to a variant of the invention, the inner central part17comprises stiffeners extending longitudinally to increase the stiffness of the metallic sheet.

The first inner flange18extends inwards from a first lateral extremity of the inner central part17, along the first longitudinal side22of the insulation material16and comprises a U-shaped bend forming an inner tenon20extending in parallel to the inner central part17, i.e. parallel to plane P, and outwards. In particular, the first inner flange18comprises a first inner section substantially perpendicular to the inner central part17, extending between the first lateral extremity of the inner central part17and the inner tenon20.

In particular, the inner tenon20comprises two parallel branches linked by a U-turn. More preferably, the two parallel branches have substantially the same length.

The second inner flange19extends inwards from the second lateral extremity of the inner central part17, along the second longitudinal side23of the insulation material16and comprises a U-shaped bend forming an inner mortise21extending in parallel to the central part17, i.e. parallel to plane P, and inwards. In particular, the second inner flange19comprises a second inner section substantially perpendicular to the inner central part17, extending between the second lateral extremity of the inner central part17and the inner mortise21.

The inner tenon20and inner mortise21have shapes that allow their interlocking when one panel2is assembled with an adjacent panel2. Preferably, their shapes are substantially complementary and their dimensions are such that:The width of the inner mortise21(measured along the Y axis) is substantially equal to the width of the inner tenon20,The length of the inner mortise21(measured along the Z axis, starting from the uncovered part of the second longitudinal side23of the insulation material16) is superior or substantially equal to the length of the inner tenon20(measured along the Z axis, starting from the uncovered part of the first longitudinal side22of the insulation material16),The position of the inner mortise21(i.e. the distance measured along the Y axis between the lowest portion of the inner mortise21and plane P) is substantially equal to the position of the inner tenon20(i.e. the distance measured along the Y axis between the lowest portion of the inner tenon20and plane P).

Preferably, the shape and dimensions of the inner tenon20are such that it perfectly fits into the inner mortise21. By “perfectly fits” it is meant that the inner tenon20and the inner mortise21are substantially in contact to one another except in areas where a gasket is added for sealing purposes, such as airtightness or thermal insulation. In particular, the inner mortise21comprises two parallel branches linked by a U-turn. More preferably, the two parallel branches have substantially the same length. The internal distance between the two parallel branches is substantially equal to the external distance between the two parallel branches of the inner tenon20. The U-turn of the inner tenon20and the U-turn of the inner mortise21are preferably separated by a gap allowing the insertion of a gasket, positioned in the U-turn of the inner mortise21before assembling of the panels2. The gasket can be, among others, of an elastomeric material which is preferably shaped to substantially conform to the shape of the inner mortise21on assembly, PVC foam, PU foam, PVC hollow section joint or of an intumescent material, such as a mineral fibre based mat incorporating phosphate or exfoliating graphite. In addition a gasket27is also added at least against the lateral edge22of the panel2for sealing purposes.

The outer metallic sheet1is a metallic sheet of rectangular shape, comprising longitudinal edges and transversal edges, which has been formed at a previous stage. It comprises, in cross-section perpendicular to its longitudinal axis X, a main part further called outer central part3and two lateral flanges further called outer flanges4,7and extending inwards from each extremity of the outer central part3. Preferably, most of the outer central part3is lying down in plane P.

The first outer flange4extends inwards from a first extremity of the outer central part3, along the first longitudinal side22of the insulation material16and comprises a U-shaped bend forming an outer tenon13extending outwards and in parallel to the inner tenon20. This outer tenon13is on the same side of the panel2than the inner tenon20.

The outer tenon13is linked to the outer central3part by a S-shaped bend5followed by a step6. The functions of these S-shaped bend5and step6are detailed further in the description. In another embodiment not depicted, the outer tenon13is linked to the outer central3part only by the step6.

The outer tenon13comprises two parallel branches linked by a U-turn. More preferably, the two parallel branches have substantially the same length.

The outer tenon13and the inner tenon20are aligned one above the other. In other words, the base of the outer tenon13and the base of the inner tenon20are in the same vertical plane, perpendicular to plane P. More preferably, the base of one parallel branch of the outer tenon13and the base of one parallel branch of the inner tenon20are in the same vertical plane, perpendicular to plane P. More preferably, the vertical plane in question is the plane of the uncovered part of the first longitudinal side22of the insulation material16.

The second outer flange7extends inwards from a second extremity of the outer central part3, along the second longitudinal side23of the insulation material16and comprises a U-shaped bend forming an outer mortise14extending inwards and in parallel to the inner mortise21. This outer mortise14is on the same side of the panel2than the inner mortise21. In particular, the outer mortise14is linked to the outer central part3by a protrusion8which is in the form of an external male projecting form comprising two opposite lateral walls9,10parallel to plane P and a free end11that protrudes from the corresponding longitudinal edge of the outer metallic sheet1in order to be received in the step6linked to the outer tenon13of the adjacent panel2.

In addition, the second outer flange7comprises an inclined wall28linking the outer mortise14and the wall10of the protrusion8. The protrusion8is closed on one end by the free end11and is open on the other end to the area located between the inner central part17and the outer central part3. The corresponding opening is located at the junction between the lateral wall10and the inclined wall28.

When a first panel2and a second adjacent panel2are assembled together, the free end11of the protrusion8of the first panel2is received in the step6of the second panel2. Once the second panel2is fastened to a building structure with a fastener, for example a screw, inserted through said panel2perpendicularly to the outer metallic sheet1through the S-shaped bend5of the second panel2, the protrusion8of the first panel received in the step6of the second panel2hides the head of the fastener. In addition, a free space is thus formed and delimited by the lateral wall10of the protrusion8and the wall of the S-shaped bend5(or of the step6) of the other panel2that can be filled with an additional insulation element.

The outer tenon13and outer mortise14have shapes that allow their interlocking when one panel2is assembled with an adjacent panel2. Preferably, their shapes are substantially complementary and their dimensions are such that:The width of the outer mortise14(measured along the Y axis) is substantially equal to the width of the outer tenon13,The length of the outer mortise14(measured along the Z axis, starting from the uncovered part of the second longitudinal side23of the insulation material16) is superior or substantially equal to the length of the outer tenon13(measured along the Z axis, starting from the uncovered part of the first longitudinal side22of the insulation material16),The position of the outer mortise14(i.e. the distance measured along the Y axis between the lowest portion of the outer mortise14and plane P) is substantially equal to the position of the outer tenon13(i.e. the distance measured along the Y axis between the lowest portion of the outer tenon13and plane P).

Preferably, the shape and dimensions of the outer tenon13are such that it perfectly fits into the outer mortise14. By “perfectly fits” it is meant that the outer tenon13and the outer mortise14are substantially in contact to one another except in areas where a gasket has been added for sealing purposes, such as airtightness or thermal insulation. In particular, the outer mortise14comprises two parallel branches linked by a U-turn. More preferably, the two parallel branches have substantially the same length. The internal distance between the two parallel branches is substantially equal to the external distance between the two parallel branches of the outer tenon13. The U-turn of the outer tenon13and the U-turn of the outer mortise14are preferably separated by a gap allowing the insertion of a gasket, positioned in the U-turn of the outer mortise14before assembling of the panels2. The gasket can be, among others, of an elastomeric material which is preferably shaped to substantially conform to the shape of the outer mortise14on assembly, PVC foam, PU foam, PVC hollow section joint or of an intumescent material, such as a mineral fibre based mat incorporating phosphate or exfoliating graphite.

Preferably, the outer mortise14and the inner mortise21are aligned one above the other. In other words, the start of the outer mortise14and the start of the inner mortise21are in the same vertical plane, perpendicular to plane P. More preferably, the start of one parallel branch of the outer mortise14and the start of one parallel branch of the inner mortise21are in the same vertical plane, perpendicular to plane P. More preferably, the vertical plane in question is the plane of the uncovered part of the second longitudinal side23of the insulation material16.

Both lengths of the outer mortise14and the inner mortise21can be such that a fastener can be inserted from the outer metallic sheet1perpendicularly into the inner mortise21and into the outer mortise14. In other words, the inner21and outer14mortises are longer than the width of the fastener. In a preferred embodiment, the inner21and outer14mortises have the same length.

According to the invention, the panel2comprises a longitudinal cylindrical seal located in and all along the protrusion8away from its free end11, and compressed between the lateral walls9,10of said protrusion8. By “away from the free end”, it must be understood that the seal12is not in contact with the U-turn wall forming the free end11of the protrusion8. The seal12thus delimits an unfillable volume V in the protrusion8as illustrated onFIG.3. In other words, the foam forming the insulation material16cannot reach and expand inside the volume V of the protrusion8while the panel2is filled with said foam. Consequently, air pockets and/or partial foaming of the protrusion are prevented. Local deformations of the protrusion are thus prevented.

As an example and in a non-limitative manner, the seal12is located at the opening of the protrusion8, meaning at the junction between the inclined wall28and the considered lateral wall10of the protrusion. The seal12may also be located equidistantly between the opening and the free end11of the protrusion8or may also be located closer to the opening of the protrusion8than its free end11, for example in the first third of said protrusion8. Locating the seal12close to the opening or at the opening prevents the foam from entering most of the protrusion, which further improves the quality and ageing of the protrusion.

Advantageously, the seal12is made of a deformable material, for example rubber or any other polymeric material with similar mechanical properties than rubber.

Preferably, the seal12is cylindrical, i.e. has a round section. This makes its insertion easier since it doesn't have to be oriented.

Advantageously, the seal12is compressed in the protrusion to further prevent the foam from entering the protrusion. The ratio between the internal width of the protrusion and the diameter of the seal is preferably lower than 0.8, more preferably comprised between 0.3 and 0.8.

RegardingFIG.4, a process for the manufacturing of the panel2of the invention will now be described.

In a first step, a first metallic strip and a second metallic strip are simultaneously profiled so that the first strip29has the profile of the outer metallic sheet1and the second strip has the profile of the inner metallic tray15each comprising a main part3, respectively17, a first lateral flange4, respectively18and a second lateral flange7, respectively19as described above.

The first step is operated with2rollforming lines, where a metallic coil is uncoiled at one extremity and goes through a series of rolls to obtain the desired profile.

In the second step, a longitudinal seal12is provided in front of the opening of the protrusion8opposite to its free end11. The step of providing the seal12is carried out by continuously unwinding the longitudinal seal12from a coil30installed above the profiled metallic strip29. The unwounded seal12thus turn round by being redirected on a redirection roll31which is free in rotation, in order to be positioned in front of the opening of the protrusion8. A U-shaped spacer32helps to redirect the seal12into the correct position for the redirection roll. The respective centers of the coil30and of the roll31are stationary comparatively to the running profiled metallic strip29.

In the third step, the seal12is inserted in the opening of the protrusion8, thus delimiting the unfillable volume V in said protrusion8. The insertion of the seal12is achieved with a disc33disposed parallel to and above the inner face of the profile metallic strip29. Preferably the disc thickness is adjusted to the internal width of the protrusion, i.e. its thickness corresponds to the distance between the respective inner faces of the lateral walls9,10of the protrusion8. More precisely the center of the disc33is stationary, and the circular edge34of the disc33pushes the seal12inside the protrusion8while the profiled metallic strip29is running. The position of the disc33along the Z axis of the metallic strip is adjusted so that the seal is inserted in the protrusion at the desired position as described above.

In a fourth step, a foaming mixture is applied with a dedicated applicator on the inner side of either the profiled first metallic strip29or the profiled second metallic strip. Then the mixture foams between the profiled first metallic strip29and the profiled second metallic strip to form the insulation material16while the two strips are transported by a twin-belt conveyer and maintained at a given distance. Thanks to the seal12, no foam mixture is applied nor expands inside the unfillable volume V of the protrusion8.

Finally in a fifth step, the assembly of the profiled first metallic strip29, the profiled second metallic strip and the insulation material16is cut at the desired length in order to form one or several panels2of the invention.