EP1485545A1

EP1485545A1 - Insulating panel with deeply profiled faces, process and apparatus for manufacturing thereof

Info

Publication number: EP1485545A1
Application number: EP02722654A
Authority: EP
Inventors: Maurizio Morandi
Original assignee: Metecno SpA
Current assignee: Metecno SpA
Priority date: 2002-03-18
Filing date: 2002-03-18
Publication date: 2004-12-15
Also published as: WO2003078752A1; HUP0500790A2; HRP20040863A2; SK50022004A3; MXPA04009102A; AU2002253507A1; CZ2004979A3; CN1625635A

Abstract

The invention relates to a novel insulating panel with composite structure manufactured continuously, which has both its outer faces (2, 3) deeply profiled. This panel is very much stronger, conditions being equal, than conventional panels in which only one of the outer faces is deeply profiled. The invention also includes a method for the continuous manufacturing of the panel and an apparatus for carrying out this method.

Description

"Insulating panel with deeply profiled faces, process and apparatus for manufacturing thereof"

The invention relates to insulating panels of the type commonly used for the construction of walls, doors, roofs and the like, of civil, industrial or other kinds of buildings.

As is known, these panels have a composite structure, also called "sandwich" structure, in which there is at least one insulating layer interposed between two outer walls forming the faces at sight of the panel; the insulating material is usually a foam made of polyurethane or the like (but could also be a rock wool or other insulating material), while the faces are in most cases sheet metal.

The latter is profiled with ribs in order to increase the rigidity of the panels; many design are the possible for these ribs and for further details about some of them as well as their manufacturing methods, reference may be made to the disclosure of European patent applications No. 682159, 995594 or

International application PCT/EP95/03865.

In short, the panels described in these documents are continuously manufactured using special apparatuses starting from two strips of sheet metal which are unwound from respective coils: the two strips are fed along respective converging paths until they are brought into the parallel horizontal condition where the insulating material, be it polyurethane foam, rock wool or other, is applied between them.

The semifinished product thus obtained is then cut transversely so that, at the end of the apparatus, panels of predefined dimensions are obtained; the panels may then be completed,, if required, off line with finishing operations. The profiling of the surfaces of the panels, however, constitutes a major limitation in current state of the art.

Indeed, the metal sheets having ribs deeper than 3 mm, generally have a rigidity such that it is practically impossible to bend them in the longitudinal (axial) direction; as a consequence the known panels, in fact, have only one face deeply ribbed because otherwise it would not be possible to produce them continuously as explained above.

It should be observed that in the known apparatuses, the deeply profiled strip advances in horizontal direction so as not to have to require changes in inclination during processing, while the other strip moves above it and is flat or slightly profiled with longitudinal ribs smaller than 3 mm, thereby resulting flexible enough to be bent a few degrees and to converge towards the bottom strip.

In this context it must be pointed out that, in the present description and in the appended claims, light profiling (or fretting) of the faces of a panel is understood as any type of rib or groove having a height such that the resultant flexural rigidity is negligible compared to that of the whole panel.

This rigidity will obviously also depend on the thickness of the sheet metal and on the characteristics of the metallic material (steel, aluminium, copper, etc.) used; however, from a general point of view it may be stated in accordance with the European standards on composite panels (ECCS), that light profiling should be regarded as the one obtained with ribs having a height (or depth, whichever applies) less than 3 mm.

On the other hand, deep profiling according to the ECCS standards should be regarded as the one formed by ribs having a height greater than 3 mm and, in accordance with the Applicant's experience, preferably a height greater than 10 mm; the variability of these values depends furthermore on factors such as the thickness and type of metallic material used for the panel faces.

The fact that known panels have only one deeply profiled face for the reasons explained above, implies that in order to obtain a high structural strength it is necessary to produce panels which are thick and/or using sheet metal of considerable thickness, thereby resulting inevitably heavy. other words, the panels currently manufactured with continuous processes have limited structural strength properties compared to their weight: an improvement in their strength would therefore be desirable since, conditions being equal, an advantageous reduction in the materials used to produce them, and therefore lower costs, would be obtained among the other things.

The present invention aims therefore to improve this state of the art: namely, its object is that of providing an insulating panel to be produced continuously, having structural strength properties better than those of the currently known panels with only one profiled surface.

This object is achieved by a panel, whose features are stated in the claims which will follow.

The invention also comprises a method for producing the aforementioned panel and an apparatus for carrying out this method, whose features are also set out in the following claims.

In order to better understand the invention as a whole, a preferred but non- limiting embodiment thereof is described below, with reference to the accompanying drawings wherein: - Fig. 1 shows a perspective view of a panel according to the invention; - Fig. 2 shows schematically an apparatus for the continuous production of panels according to the invention;

- Fig. 3 shows in detail of a particular feature of the apparatus according to Fig. 2; - Fig. 4 is a cross-section along the line iN-IV in Fig. 3;

- Fig. 5 illustrates the stacking of panels according to the invention;

- Fig. 6 shows another example of apparatus for the continuous production of panels according to the invention.

With reference to these figures, in the first of them numeral 1 denotes overall an insulating panel according to the invention.

As can be seen, this panel comprises two outer faces 2 and 3 at sight, between which an insulating layer 4 is present made in this case from polyurethane foam.

The outer faces 2 and 3 are both reinforced with deep profiling as explained further above, in the form of a series of respective longitudinal ribs 5, 6 with a trapezoidal profile, which extend in relief with respect to the intermediate portions 7 and 8; the latter are profiled slightly with low ribs 9 and 10, different between one side and the other of the panel.

Obviously the profile of the faces 2 and 3 may differ from that shown in the drawings, depending on the widely varying shapes of the ribs 5 and 6; what should be herein considered is the fact that both faces have deep profiling, greater than 10 mm, thereby providing the panel with high flexural rigidity even in the case of limited thickness of the insulating layer 4.

This important result is achieved by manufacturing the panel 1 continuously with the apparatus 21 which can be seen in Figure 2, starting from two coils 22 and 23 of flat metallic strip material.

As can be seen, in this apparatus the upper coil 22 strip and the lower coil

23 strip are unrolled in a manner known per se and are then formed in respective profiling machines 24 and 25 arranged in succession; the latter have the function of profiling the strips so as to obtain the profile at sight of the faces 2 and 3 of the finished panels.

In particular, the strips which advance horizontally at different heights downstream of the profiling machines 24 and 25 are indicated by 2' and 3' respectively in Figure 2, according to what has been seen in connection with the panel of Fig. 1; this is done for the sake of simplicity of the description since, obviously, the outer faces of the panels may also be formed from the metal strips arranged in an inverted manner with respect to that of Fig. 2.

The profiling machine 24 is shown in detail in Fig. 3; it has a series of intermediate stages Si, S₂, S₃ ... S_n, in each of which a pair of shaped opposing rolls 25 and 25 of a type known per se is located.

These rolls are shaped in accordance with the profile to be formed in the strip 2' which passes through the profiling machine 24, and are mounted on corresponding frame supports Tι-T'ι, T₂-T'₂, T₃-T'₃, ... T_n-T'_n, arranged at their ends. The rolls 25 and 26 are operated by respective spindles 27 and 28, which are connected in turn to actuating motors not shown in the drawings; the heightwise position of the rolls may be adjusted by means of adjusting screws 29, 30, 31, 32 arranged in the frames of each stage, which act on the bearings 33, 34, 35 and 36 of the rolls. The purpose of this adjustment facility, in addition to ensuring the normal operating functions of the profiling machine 24 as already occurs in conventional machines, is to facilitate the passing movement of the lower strip 3' supplied by the first profiling machine 25.

Indeed, as can be seen, the already profiled strip 3' advances inside the profiling machine 24 at a lower level than the roll 26, i.e. the bottom drum, of each stage Sι-S_n; for this purpose the strip 3' is supported inside the profiling machine 24 by a series of idle rollers 38 which are located in a plane located underneath that of the rolls 26.

In accordance with this example of the invention, the profiling stages Sι-S_π are fixed on base structures 40 formed with longitudinal members 41 joined by reinforcing cross-pieces 42; these structures are modular and rest on a main base 44 of the profiling machine 24, so that they can be removed for the operations of maintenance or replacement of the profiling equipment.

The second profiling machine 25 which is located upstream of that considered above is similar to the latter, except that it does not have idle rollers arranged underneath the profiling stages; these rollers are in fact superfluous since the profiling machine does not have to be passed through longitudinally by another metal sheet, like the other machine.

For the sake of brevity, therefore, a specific description of the profiling machine 25 is omitted and for further details reference should be made to what has already been stated above. It must be pointed, however, that since the profiling machine 25 is intended for working the lower strip 3, the passage line of the latter (the so-called "pass-line") defined by the nip between the shaped rolls is located at a lower level than the pass-line of the first profiling machine 24. Consequently the positioning height of the shaped rolls of the second profiling machine 25 in the respective support frames, will be different from that of the rolls shown in Figure 3; what is important, however, is that inside the apparatus 21, the upper and lower strips 2' and 3' advance horizontally parallel to each other towards the zone for application of the insulating material. Nozzles 50, 51 operate in this zone, spraying onto one or both strips 2', 3' the polymer substances which are usually used to form the insulating layer 4 of the panels; downstream the nozzles a continuous belt press 55 known per se is located.

At the end of the apparatus, finally, there is a cutting station 60 where the semifinished product continuously obtained, is cut transversely into pieces of the desired length, thus forming the panels 1 ; it must be pointed out, however, that the latter may undergo other processing operations off line, which are not considered in this example.

From wath has been stated hitherto it is possible to understand operation of the apparatus 21 and how it allows continuous manufacturing of panels according to the invention.

Indeed, by arranging the profiling machines 24 and 25 one downstream the other, it becomes possible to perform deep profiling of the flat metal strips supplied by the reels 22 and 23, keeping them in a position close to each other which is later useful for injection of the insulating foam and, more generally, for any subsequent operation envisaged in the production cycle.

In other words, with this arrangement of the profiling machines, the strips

2' and 3' are not subject to significant incline variations along their travel path after they have been profiled: in this way it is thus avoided flexing them at angles which would be incompatible with their deep profiling. It should be noted, however, that the strip sections downstream of the coils 22, 23 do not raise these difficulties because they are flat.

In the apparatus thus configured it is therefore possible to introduce the two strips 2' and 3' in a substantially parallel condition into the continuous press 55.

Indeed, since the strips are profiled along respective levels located close to each other, downstream of the profiling machines 24 and 25 they may be conveyed towards the press 55 with a negligible inclination relative to the horizontal, actually less than 1-2°. hi practice this inclination is determined by the deformation camber of the strips 2' and 3' before entering the continuous press.

On the basis of this teaching it is not difficult to understand that it is possible to manufacture panels with any type of deep profiling on both faces at sight, whose example shown in Figure 1 represents only one of the possible embodiments.

These panels achieve the object of the invention set forth initially.

It is indeed obvious that the double deep profiling increases substantially the structural properties of the panels, all other conditions being equal, without increasing substantially the weight (incidence of steel and insulating material per square metre of panel); the outcome of this is therefore that the limitations of the known panels referred to above are completely overcome by the invention.

The latter also includes the method for the continuous production of the panels.

As explained farther before, the conventional apparatus are not suitable for deeply profiling both faces of the panels because the spaced arrangement of the profiling machines, such as for example that shown in European patent application No. 995594, involves necessarily bending angles of the upper strip in order to guide it towards the lower strip, which are incompatible with deep profiling. With the manufacturing method according to the present invention it is possible to overcome this technological limitation.

Indeed, the profiling of the strips now occurs along respective levels which are at distance substantially equal to the final thickness of the panels: it follows, therefore, that downstream of the profiling machines the upper strip does not have to undergo significant deviations which may require longitudinal bending thereof about an axis transverse to the direction of feeding, which would be incompatible with deep profiling thereof. h particular, in apparatus 21 this result is achieved by arranging the profiling machines 24, 25 one after another and keeping the strips at a close distance such that, downstream of the profiling machines, they may be conveyed towards the continuous press in a substantially parallel condition relative to each other.

In practice, after the profiling machine 24, the strips 2' and 3' converge with an inclination which is preferably less than, or equal to, 1° until they reach a distance between them, corresponding to the final thickness of the panel.

Of course, variations of the invention with respect to the foregoing embodiment are possible.

Reference has already been made to the possibility of varying, as required, the profile of the surfaces 2 and 3 depending on the type of ribs which are to be formed thereon. In this context, however, it is should be emphasised that the trapezoidal profile of the ribs of the panel shown in Fig. 1, wherein the male ribs 5 have a tapered profile which can be combined with that of the female ribs 6 of a panel arranged on top (and vice versa), has the advantage of allowing stacking of the panels keeping to the minimum the empty spaces, as shown in Figure 5.

It should be noted that this advantage assumes particular importance in connection with the industrial transportation of panels where the maximum volume, instead of the maximum weight, transported is always a determining factor. The known panels which have only one surface or side with deep profiling, while the other side is substantially flat, are usually transported turned over with respect to each other with the sides where ribs are formed being arranged facing one another.

Such a solution results in a considerable amount of empty spaces between the panels thereby, negatively affecting the transportation costs, since for a given loading volume, the number of panels which can be transported is inevitably limited by the empty spaces present between them.

On the other hand, panels with deep profiling on both sides in accordance with the invention may be stacked by combining the respective profiles, so as to reduce significantly the empty spaces for transportation.

It can be understood, however, that this effect may be obtained with ribs having a profile different from the trapezoidal profile of the example shown, since it is necessary only that their shape be of the male/female type which can be geometrically combined as explained above. By way of a further possible variant of the invention it has also be mentioned that the insulating layer must not necessarily consist of polyurethane foam, but might also be formed with any other suitable material such as, for example, rock wool, glass and the like.

It must however be remembered that for such an alternative, it is preferable to modify the panel production apparatus with respect to that shown in

Fig. 2, because the application of the rock wool may be better performed between one profiling machine and the other, i.e. before the upper strip 2' is brought to a distance substantially equal to the final thickness of the panels, relative to the lower strip 3'. For application of the rock wool it is nevertheless possible to use the normal systems known for this purpose, arranging the corresponding machinery between the two profiling machines 24, 25 which for this reason must therefore be located at a suitable distance.

It can moreover be understood that the presence of the insulating-wool application means between the two profiling machines is not incompatible with the polyurethane-foam injection means, since it would allow the formation of an apparatus of the dual-purpose type, i.e. capable of producing both foam-filled panels and wool-filled panels. h this connection it must also be pointed that profiling of the strips could be performed in an inverse manner with respect to that described for the apparatus of Fig. 2, namely by processing first the upper strip and thereafter the lower strip, with the position of the profiling machines 24 and 25 being interchanged.

An example of this situation is shown in Fig. 6 where, for the sake of simplicity, numbering of the preceding embodiment has been maintained. It just has to be pointed out that in this apparatus the upstream profiling machine 24 which processes the upper strip 2 will no longer have idle rollers 38 for supporting the lower strip while on the other hand, the profiling machine 25 will be provided with such rollers which obviously will be positioned above the shaped rolls which profile the lower strip 3'.

All these variants nevertheless fall within the scope of the following claims.

Claims

1. Composite panel comprising at least one insulating layer (4) interposed between two outer faces (2, 3), characterized in that both faces are formed by deeply profiled metal sheets.

2. Panel according to Claim 1, wherein the depth of the profiling of the outer faces (2, 3) is greater than 3 mm.

3. Panel according to Claim 2, wherein the depth of the profiling of the outer faces (2, 3) is greater than 10 mm.

4. Panel according to Claims 1 to 3, wherein said at least one insulating layer (4) is made of materials comprising: polymer foam or rock wool.

5. Panel according to any one of the preceding claims, wherein the outer faces (2, 3) are profiled with male ribs (5) and/or female ribs (6), fitting the conjugate ribs of similar panels in the stacked condition.

6. Panel according to Claim 5, wherein said male ribs (5) and female ribs (6) have a trapezoidal profile.

7. Method for the continuous manufacturing of panels according to any of Claims 1 to 6, comprising the following steps in combination:

- feeding longitudinally an upper metal strip (22, 2') and a lower metal strip (23, 3'); - profiling said strips in the longitudinal direction;

- applying an insulating layer (4) between the strips;

- compressing, in a continuous press (55), the semifinished product formed by the strips and by the insulating layer arranged therebetween, until the thickness of the panels to be produced is reached; - transversely cutting said semifinished product in order to obtain panels of predefined length; characterized in that profiling of the upper strip (2') and lower strip (3') is performed along respective pass-lines located close to each other such that the profiled strips enter the continuous press (55) in a substantially parallel condition.

8. Method according to Claim 7, wherein the profiled strips (2 3') enter the press (55), converging towards each other at an angle of less than 1°.

9. Method according to Claim 8, wherein the steps involving profiling of the strips (2, 3') are performed in succession along a common horizontal feeding direction.

10. Method according to Claim 9, wherein profiling of the strips (2 3') is greater than or equal to 10 mm.

11. Method according to Claim 10, wherein the insulating layer (4) is obtained using a foam of polymer material applied between the strips (2', 3') during a step following profiling thereof.

12. Method according to Claim 10, wherein the insulating layer (4) is obtained using rock wool or the like applied during an intermediate step between the profiling of the strips (2 3').

13. Apparatus for carrying out the method of Claims 7 to 12, comprising a first and a second profiling machine (24, 25) processing respectively an upper strip (2') and a lower strip (3'), a continuous press (55) located downstream the profiling machines, characterized in that the strips are profiled along respective pass-lines close to each other and enter the continuous press in a substantially parallel condition.

14. Apparatus according to Claim 13, in which the profiled strips (2', 3') enter the continuous press (55), converging towards each other at an inclination of less than 1°. '

15. Apparatus according to Claim 14, in which the profiling machines (24, 25) are arranged in mutual succession in the direction of feeding of the strips (2', 3') such that the machine which is located downstream is passed through by the strip (2', 3') supplied by the other profiling machine and is equipped with means (38) for supporting this strip.

16. Apparatus according to Claim 15, wherein the means supporting the strip (2', 3') are idle rollers (38).