IE890253L - Manufacturing insulating panel - Google Patents

Description

6 0 6 3 0 The invention relates to a method for manufacturing an insulating panel of the type comprising a profiled external skin and an internal backing tray having an insulating core therebetween According to the invention there is provided a method for manufacturing an insulating panel of this type comprising the steps of s conveying a profiled external skin continuously along a flat bed with the outer surface of the skin 10 lowermost j. applying liquid insulating foam reactants onto the external skinP leading a backing tray continuously over the external skin, heating the assembly in an oven to allow the liquid foam reactants to expand to form an insulating core between the internal tray and external skin to form an insulating panelf and cutting the panel to a desired length. 1 In a particularly preferred embodiment of the invention the airtem&l skin is cut to length and releasably attached to a following external skin prior to application of the backing tray.

Preferably adjacent pre-cut lengths of external skin are overlapped transversely prior to application of the liquid 5 foam reactants.

Typically the lengths of external skin are overlapped and attached by an adhesive tape.

In a preferred embodiment of the invention the trailing edge of one external skin is overlapped onto the leading edge of a 10 following external skin.

In one embodiment of the invention the backing tray and portion of the foam core are cut at the joint between overlapping panels so that on separating of the overlapping panels a clean transverse joint between overlapping panels in 15 use from external skin to external skin may be made.

Preferably the backing tray and foam core at the joint are cut by a two step process , namely a first cutting step in which a cut through the backing tray and preferably portion of the insulating core is made automatically and a second cutting 20 step in which the remaining portion of the foam is manually cut.

In a preferred embodiment of the invention the first cutting step is initiated by a control system comprising a means for indicating the location of an overlapping joint, and sensing 25 means for the indicating means, a saw being activated on actuation of the sensing means.

Preferably the indicating means comprises an indicating mark which is marked on the trailing edge of each external skin.

Typically the sensing means comprises a photoelectric sensor for sensing the position of the mark.

In a preferred, embodiment of the invention the backing tray and external skin are pre-heated prior to application of the 5 liquid foam reactants.

Preferably side sealing means are provided between the external skin and the backing tray.

Preferably the side sealing means comprises a sealing tape extending along at least one longitudinal edge of the panel.

Typically the side sealing tape is applied at the joint between the external skin and the backing tray at or prior to application of the liquid foam reactants.

In a preferred embodiment of the invention the backing tray and insulating core terminate inwardly of one of the 15 longitudinal side edges of the external skin to accomodate longitudinal overlapping of adjacent panels, in use.

Preferably the external skin is of a metal material such as steel or aluminum.

Preferably the backing tray is of a metal material such as 20 steel or alusiinium.

In a preferred embodiment of the invention at least those surfaces of the skin and/or backing tray which are exposed in use are coated for corrosion resistance.

Preferably the core is of a rigid closed cell polyurethane or 25 polyisocyanurate foam material™ - 5 The invention also provides an insulated panel whenever made by the method of the invention. The panel may comprise a profiled external skin and an internal backing sheet having an insulating core therebetween wherein the tray and core 5 terminate at a location spaced-apart from a transverse edge of the panel for direct overlapping from an external skin of one panel to the external skin of another panel at a transverse joint between adjacent panels.

The invention will be more clearly understood from the 10 following description thereof given by way of example only with reference to the accompanying diagrammatic drawings of the various steps of the method of the invention which, in detail,» are as follows: Fig. 1 is* a perspective view of a first stage 15 overlapping of adjacent present profiled external skins, Fig. 2 is a perspective view of the skins overlapped, Fig. 3 is a plan view of portion of the method for 20 applying an internal backing tray and insulating material to the external skin.

Fig. 4 is a plan view similar to Fig. 3 on an enlarged scale, Fig. 5 is a side view of the portion of the method 25 illustrated in Fig. 4, Fig. 6 is a side partially cross sectional view of the foam reactants applications step up the process, Fig. 7 is a longitudinal cross sectional view of two profiled external skins overlapped, Fig. 8 is a transverse cross sectional view on the line VIII VIII in Fig. 6, Fig. 9 is a plan view of cutting steps of the method, Fig. 10 is a side view of the cutting steps of the method of Fig. 9, Fig. 11 is a side cross sectional view on an enlarged scale of the cutting steps of the method, Fig. 12 is a transverse cross sectional view of an insulating panel formed by the method of the invention, Fig. 13 and 14 are respectively side and perspective views illustrating the overlapping of two adjacent panels in use.

Referring to the drawings the method of the invention is for forming an insulated panel of the type which is illustrated in detail in Figs. 12, 13 and 14 and indicated generally by the reference numeral 1. The panel 1 comprises a profiled external skin 2 which is typically of steel or aluminum materialan internal backing tray 3 which again is typically of steel or aluminum material and an insulating core 4 typically of polyureth&ne or polyisocyanurate foam material between the skin 2 and tray 3. The thickness of the foam layer is variable. The insulated panel 1 is typically used for roofing and cladding systems, adjacent panels being overlapped both longitudinally and transversely to clad or roof a particular area. It will be noted from Fig. 12 in - 7 ~ particular that the backing tray 3 and the foam insulating core 4 do not extend the full width of the panel 1 but terminate at the inner most edge of the outer profile channel to define an overlapping portion 10 which is free from 5 insulating material and the backing tray 3 and which, in usat overlaps longitudinally onto the outer skin 2 of an adjacent panel. The overlapping portion onto which the portion 10 of another panel 1 overlaps is illustrated by the reference numeral 11 in Fig. 12.

Referring particularly to Figs. 13 and 14 it will also be noted that in this case the internal skin 3 and foam core 4 terminate at a distance spaced inwardly from the free transverse edge at one end of the panel 1 for overlapping with an adjacent panel with direct contact between the profiled 15 external skin 2 of adjacent panels to ensure that no water ingress occurs at the joint.

The panel 1 according to the invention is formed by a method also according to the invention. Firstly, as illustrated in Fig. 1. cut lengths of external skin 2 are laid down and then 20 marked with two marks, one at either end. A first mark 15 is made adjacent the free trailing edge of the skin 2 as illustrated in Fig. 1 and a second mark IS is made at a distance inwardly from the leading edge of the skin 2 corresponding to the desired overlap between adjacent panels 25 1 in use. The location of the second mark 16 will vary depending on the application for the panel 1. When the panel 1 has been marked up as indicated, in Fig. 1 the trailing edge of the external skin of a preceding panel in the line indicated by the reference numeral 20 in Fig. 1 is lifted up 30 and. placed down on the leading portion of the panel 1 until the trailing edge of the panel 20 is in line with the second indicating mark 16. The joint between the skins 20, 2 is then made by a releasable fastening means, in this case £. an adhesive tape 25 which is laid down across the joint between the skins 20, 2. It will be noted that in this initial overlapping procedure and during the entire method for forming the insulated panel the external skin 2 lies with its outermost side lowermost on a bed. This is an important 5 feature of the invention and the advantages of this particular arrangement will become apparent from the description below.

Referring particularly to Figs. 3 to 6 the next step in the method of the invention is to apply liquid foam reactants to the skin 2. The foam material is injected onto the skin 2 10 through nossles 35 which are fed from supply tanks 35, a mixer 37 and conduits 38. The backing tray 3 is drawn continuously from a roll 30 and is led downwardly from the roll 30 at an angle as illustrated in Figs. 5 and 6. To ensure bonding between the foam and the inner surfaces of the skin 2 and tray 15 3 these surfaces are first pre-heated typically by infra red radiation from a skin heat source 31 and a backing tray heat source 32 illustrated particularly in Fig. 5» The spacing between the backing tray 3 and the skin 2 is dependent on the thickness of foaia core which is desired. The spacing is set 20 by a number of spacer blocks (not shown) which retain the tray and skin spaced-apart until the foam reactants expand to the desired thickness to fill the space between them. As the backing tray 3 is applied it is shaped by profiling rollers into the final shape illustrated in Fig. 12. As the backing 25 tray 3 is being applied a longitudinally extending sealing tape 40 is applied between the backing tray 3 and the skin 2 as illustrated in Fig. 12 to confine the foam core 4 in the desired space illustrated in Fig. 12. The skin 2 with the liquid foam reactants applied and the tray 3 are then passed 30 through an oven 48 where the liquid foam reactants are heated and allowed to expand to the desired thickness of foam insulating core 4.

The final stage in the method is illustrated particularly in 35 Pigs. 9 to 11 and in this case involves a two stage cutting „ 9 - method. The initial first stage cutting step is made by a cross cut saw 50 which is mounted for transverse movement across the panel in a frame 51 which frame 51 is in turn mounted on tracks (not shown) to move with the panel as it is 5 passing along the conveyor. The saw 50 is automatically actuated when a photoelectric sensor 55 picks up the first mark 15 made on the skin 2. The first cutting step cuts through the backing tray 3 fully and portion of the depth of the foam insulating core 4 as illustrated on the right hand 10 side of Fig. 11. The panel then passes through a second cutting station where the remaining depth of the foam core 40 is manually cut by a second, saw 60. When the backing tray and form core are cut through the skins 2, 20 are easily pulled apart and the tape 25 removed leaving a clean joint between 15 the adjacent skins 2,20 as illustrated in Figs. 13 and 14.

The advantages of the method of the invention are many. Firstly, because of the various features of the method and in particular the fact that the outer skin is laid down with its outer side lowermost rather than the other way around, the 20 continuous production of the insulated panels of the invention is facilitated. The various features of the method allowing clean overlap between adjacent panels to be made in use are also of particular importance as they provide panels which effectively give direct skin to skin contact at overlaps which 25 is very important in ensuring that no ingress of water occurs at overlapping joints in use.

The invention is not limited to the embodiments hereinbefore described which may be varied in both construction and detail.

Claims (26)

1. A method for manufacturing an insulating panel of the type comprising a profiled, external skin and an internal backing tray having an insulating core therebetween, the 5 method comprising the steps of: conveying a profiled external skin continuously along a flat bed with the outer surface of the skin lowermost, applying liquid insulating foam reactants onto the 10 external skin, leading a backing tray continuously over the external skin, heating the assembly in an oven to allow the liquid foam reactants to expand to form an insulating core 15 between the internal tray and external skin to form an insulating panel, and cutting the panel to a desired length.

2. A method, as claimed in claim 1 wherein the external skin is cut to length and releasably attached to a following 20 external skin prior to application of the backing tray.

3. A method as claimed in claim 2 wherein adjacent pre-cut lengths of external skin are overlapped transversely prior to application of the liquid foam reactants.

4. A method as claimed in claim 3 wherein the lengths 25 of external skin are overlapped and attached by an adhesive tape . - 11 -

5. A method as claimed in any of claims 2 to 4 wherein the trailing edge of one external skin is overlapped onto the leading edge of a following external skin. f/

6. A method as claimed in any of claims 2 to 5 wherein 5 the backing tray and portion of the foam core are cut at the joint between overlapping panels so that on separating of the overlapping panels a clean transverse joint between overlapping panels in use from external skin to external skin may be made. 10

7. A method as claimed in claim 6 wherein the backing tray and foam core at the joint are cut by a tvo step process, namely a first cutting step in which a cut through the backing tray and portion of the insulating core is made automatically and a second cutting step in which the remaining portion of 15 the foam is manually cut.

8 - A method as claimed in claim 7 wherein the first cutting step is initiated by a control system comprising a means for indicating the location of an overlapping joint,, and sensing means for the indicating means, a saw being activated 20 on actuation of the sensing means.

9. A method as claimed in claim 8 wherein the indicating means comprises an indicating mark which is marked on the trailing edge of each external skin.

10. A method as claimed in claim 9 wherein the sensing 25 means comprises a photoelectric sensor for sensing the position of the mark.

11. A method as claimed in any preceding claim wherein the backing tray and external skin are pre-heated prior to application of the liquid foam reactants. - 12 ~

12. A method as claimed in any preceding claim wherein side sealing means are provided between the external skin and the backing tray.

13. A method as claimed in claim 12 wherein the side 5 sealing means comprises a sealing tape extending along at least one longitudinal edge of the panel.

14. A method as claimed in claim 13 wherein the side sealing tape is applied at the joint between the external skin and the backing tray at or prior to injection of the liquid 10 foam reactants.

15. A method as claimed in claim 13 or 14 wherein the backing tray and insulating core terminate inwardly of one of the longitudinal side edges of the external skin, to accomodate longitudinal overlapping of the adjacent panels, in use„ 15

16. A method as claimed in any preceding claim wherein the external skin is of a metal material.

17. A method as claimed in claim 16 wherein the external skin is of steel material.

18. A method as claimed in claim 16 wherein the external 20 skin is of aluminum material.

19. A method as claimed in any preceding claim wherein the backing tray is of a metal material.

20. A method as claimed in claim 19 wherein the backing tray is of steel material. 25

21. A method as claimed in claim 19 wherein the backing tray is of aluminum material. - 13 -

22. A method as claimed in any of claims 16 to 21 wherein at least those surfaces of the skin and/or backing tray which are exposed in use are coated for corrosion resistance. 5

23. A method as claimed in any preceding claim wherein the core is of a rigid closed cell polyurethane or polyisocyanurate foam material.

24. A method substantially as hereinbefore described with reference to the drawings. 10

25. An insulated panel whenever prepared by a method as claimed in any preceding claim.

26. An insulated panel as claimed in claim 25 in which the panel comprises a profiled external skin and an internal backing sheet having an insulating core therebetween wherein 15 the tray and core terminate at a location spaced-apart from a transverse edge of the panel for direct overlapping from an external skin of one panel to the external skin of another panel at a transverse joint between adjacent panels. Dated this 27th day of January, 1989 20 CRUICKSHANK & CO. Agents for the Applicant 1 Holies Street Dublin 2