PANEL

FIELD OF THE INVENTION

[0001] This invention relates to a method, apparatus and system for manufacturing an insulated panel.

BACKGROUND TO THE INVENTION

[0002] Insulated panels are useful for building construction, for example for cladding and for the construction of internal walls of a structure. Insulated panels may also be used for other purposes. Though various insulated panel designs are available, a typical structure includes a laminate of two outer skins or sheets bonded about a core of insulation material such as polyurethane (PU) or polyisocyanurate (PIR) resin though a range of suitable insulation materials are available and selection may depend on density and thermal or acoustic insulation properties. The core also typically contains a fire retardant and may be fibre reinforced.

[0003] Where a polymer foam core is to be formed, a mixture of reagents which react to form polyurethane are introduced during the panel manufacturing process. Such processes are typically continuous to promote output and a bottom sheet is typically fed along a conveyor with damming to contain the mixture of reagents when received from a feeding apparatus. A top sheet is then brought into co-operation with the curing reagent mixture and pressed into position so that both the top and bottom sheets are bonded to the polyurethane foam once cured under high temperature and pressure. The reagent mixture is desirably fed to the bottom sheet and damming as quickly as possible because curing time is a function of the reagent mixture feed time. [0004] The Applicant understands than current insulation panel manufacturing methods, where a PU or PIR core is required, require a feed time of about 25 seconds and a curing time of about 20 minutes. This does not seem long but panel manufacturing costs as well as overall insulated panel installation costs are impacted by these metrics.

[0005] It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.

SUMMARY OF THE INVENTION

[0006] In some embodiments, there is provided a method and apparatus for manufacturing an insulated panel which may optimise reagent mixture feeding time with benefits for curing time, overall insulation panel manufacturing time and, where possible, insulation panel installation lead times and costs.

[0007] In some embodiments, there is provided a method for manufacturing an insulated panel including outer sheets and a polymer resin core disposed between the outer sheets. The method may include the steps of:

(a) conveying a sheet by first conveyor to form a first outer sheet of an insulated panel in a first direction;

(b) depositing a reagent composition to form a polymer core for the insulated panel on the outer sheet during conveying; and

(c) applying at least one further sheet to the first outer sheet as the reagents react to form the polymer core.

[0008] In some embodiments, the at least one further sheet is applied from the first direction. [0009] In some embodiments, the at least one further sheet is applied from a second direction that is different to the first direction.

[0010] The second direction may be perpendicular to the first direction. In this case, the first sheet may be conveyed by the first conveyor with the at least one further sheet then being applied from the side of the conveyor, either manually or by second conveyor. However, the second direction may be a different angle than perpendicular if necessary.

[0011 ] The first and second conveyors may comprise a system of conveyors if required.

[0012] Conveying may include pushing or pulling the sheets in the respective directions.

[0013] Pressure may be applied, by a press, to either sheet during conveying, such pressure being applied to promote bonding between the sheets and polymer resin core.

[0014] Single pass conveying through the press is expected to be sufficient.

[0015] Conveniently, only one further sheet is required and this may be termed a second sheet.

[0016] The second sheet may be prepared on a surface, or table, adjacent the first conveyor and may be fed manually from the side of the first conveyor if desired.

[0017] Sheets may be prepared from a range of suitable cladding materials, having reference to properties such as fire retardancy and applicable standards (e.g. building or fire standards). Ceramic sheets, for example of MgO, are preferred.

[0018] The product insulated panel may include one or more structural members. The structural members may, for example form a frame of the panel. The structural members may be disposed along any or all of the sides of the panel when produced.

[0019] During manufacture, the structural members are arranged as required on the first sheet and the polymer resin is deposited such that the structural members have portions embedded in the cured polymer core of the product insulated panel. Structural members can be embedded in a manner to leave connection means for connecting structural members to complementary connection means of other structural members of other panels if required.

[0020] The first and further sheet (s) may be provided as a mould and/or is preferably provided with a containment or damming means (analogous to formwork) for containing the reagent composition, including selectively containing the reagent composition in selected locations, as it is deposited and the polymer core as this forms. Such mould or containment means may form part of the product insulated panel or be removed prior to dispatch of product insulated panels.

[0021 ] Desirably, the polymer core (which typically expands as it forms) should rise to a level that facilitates bonding with the second sheet, conveniently a level about equal to the height of the mould or containment means.

[0022] Deposition may be done in a number of ways. For example, deposition may comprise one or more of injection, spraying and pouring of the reagent mixture. However, polymer reagents could be otherwise delivered to the containment means as part of the method. [0023] The product insulated panel may be used for a range of purposes, for example in the construction of a range of structures. Such structures typically include components such as doors, windows, cable ducts, gutters and so on; and accommodation for such components.

[0024] Where feasible, frames or accommodation for such components may be included within a pre-form, for example being a core structure of the insulated panel because such structural components are conveniently located within the core structure, or formed during the method.

[0025] The containment means may include further containment means which prevent reagent entering zones that may later be required for such components, or to accommodate such components. For example, in the case of a window, a window frame may be included with a containment means to prevent polymer resin entering a zone that will later become a window. Other like examples are readily apparent.

[0026] Structural components within the preform or core structure may act as containment means for the reagent composition and product polymer.

[0027] A product insulated panel may be a self-supporting building module for constructing a structure, for example as described in the Applicant’s co-pending Australian Provisional Patent Application No. 2017902629, filed 5 July 2017, the contents of which are hereby incorporated herein by reference. In such case, either sheet may be applied in assembly with a frame, structural members or other building components forming part of the structure to be constructed.

[0028] A range of polymer resins, and corresponding reagent compositions, may be used to form the core.

[0029] Polyurethane and polyisocyanurate resins are particularly preferred with properties such as density and thermal and acoustic insulation properties being selected as required for the application in which product insulated panels are to be used.

[0030] Conveniently, reagent mixture is deposited selectively to ensure that polymer resin is formed only at required locations within the panel, for example where required for thermal or acoustic insulation purposes and not, for example, injected to locations to become doors, windows or other accommodation for building components.

[0031] In some embodiments, there is provided an apparatus for manufacturing an insulated panel including outer sheets and a polymer resin core disposed between the outer sheets. The apparatus may include:

(a) a first conveyor for conveying a sheet of material to form a first outer sheet of an insulated panel in a first direction;

(b) a delivery system for depositing a reagent mixture to form a polymer resin core for the insulated panel on the outer sheet during conveying; and

(c) means for applying at least one further sheet to the first outer sheet as the reagent mixture reacts to form the polymer resin core.

[0032] In some embodiments, the application means is oriented to apply the at least one further sheet from the first direction.

[0033] In some embodiments, the application means is oriented to apply the at least one further sheet from a second direction different to the first direction.

[0034] In another embodiment, there is provided a method for manufacturing an insulated panel including:

(a) forming at least a portion of an insulated panel;

(b) applying a first sheet for protecting the insulated panel portion; (c) conveying said insulated panel portion and said sheet in the same direction into a press;

(d) selectively depositing a reagent composition within the insulated panel portion to form a polymer core for the insulated panel;

(e) bonding the insulated panel portion to said first sheet; and

(f) producing the insulated panel.

[0035] As described above the product insulated panel may be used for a range of purposes, for example in the construction of a range of structures. In the case of a structure, the insulated panel may have length of an entire wall section, for example being several metres in length and a few metres in width. Such a wall section can therefore be manufactured continuously reducing the number of panels in the wall section and reducing installation cost. Such structures typically include structural components such as doors, windows, cable ducts, gutters and so on; and accommodation for such structural components.

[0036] Where feasible, frames or accommodation for such components may be included within a pre-form or mould forming the insulated panel portion, for example being a core structure of the insulated panel because such components are conveniently located within the core structure, or formed during the method.

[0037] For ease of description, the term core structure is used below but it will be understood that the insulated panel portion is not limited to the core structure. In the case of a core structure, this may include a further or second sheet.

[0038] The core structure and sheet(s) are advantageously conveyed into the press at the same time. The press is used to apply pressure to the first sheet and the core structure to ease bonding of the outer sheet to the core structure through the polymer resin core. [0039] Locations for deposition may be actively or passively controlled, for example by a control unit controlling the deposition of reagent composition by a reagent composition delivery means.

[0040] Alternatively, or additionally, containment means or damming may be used to confine deposited reagent mixture and product polymer to particular locations of the core structure and not in locations which do not require it, for example in locations for doors and windows. Single pass conveying of sheets and core structure through the press is expected to be sufficient.

[0041 ] Advantageously, while the core structure and first sheet are conveyed into the press at the same time, different conveyors are used for core structure and first sheet.

[0042] A first conveyor conveys the first protective sheet into the press. A second conveyor conveys the core structure into the press.

[0043] The first conveyor is conveniently disposed at an acute angle to the second conveyor with both conveyors delivering the core structure and first protective sheet to a feed end of the press. The core structure and first sheet are advantageously fed to the press at the same feed rate. The production rate may be different dependent on time required within the press.

[0044] The core structure may itself include a second protective sheet. One embodiment of insulated panel produced by the method would include two outer sheets with a polymer resin core disposed between them.

[0045] The outer sheets would be of a suitable cladding material. Insulated panels could include a plurality of sheets disposed about a polymer resin core and laminated outer sheets could also be produced by the method. [0046] The core structure, whether including a second protective sheet or not, may be formed in a mould in step (a).

[0047] In another embodiment, there is provided an apparatus for manufacturing an insulated panel including:

(a) a first conveyor for conveying an insulated panel portion towards a press;

(b) a second conveyor for conveying a first sheet towards the press;

(c) a reagent deposition delivery system for selectively depositing a reagent mixture within the core structure to form a polymer resin core for the insulated panel; and

(d) a press for bonding the core structure to said first sheet through the polymer core.

[0048] Again, and as described above, a desirable insulated panel portion is a core structure for the product insulated panel. The term core structure is used below for ease of description and is not intended to be limiting.

[0049] The core structure may itself include a second protective sheet, conveniently as a base or top surface.

[0050] The second conveyor is conveniently disposed at an acute angle to the first conveyor with both conveyors delivering the core structure and first protective sheet to a feed end of the press.

[0051] One of the conveyors, particularly for the core structure, is preferably disposed substantially horizontally in alignment with a feed end of the press. The first and second conveyors may include rotating rollers to assist travel of core structure and first sheet. [0052] The apparatus may include guide means to assist travel of the first sheet, bending it where necessary, and to ensure the correct tension is maintained in the first sheet.

[0053] The guide means may include a set of opposed rollers between which the first sheet stock travels.

[0054] The press conveniently includes two conveyor portions spaced apart a sufficient distance to accommodate travel of the core structure and first sheet between them, desirably under pressure as this facilitates the bonding process.

[0055] The conveyor portions may be tracked or provided with any required profiled structure. The first sheet, which may form the top sheet or board, may be brought under pressure by the press prior to the polymer resin rising to contact the first sheet.

[0056] The core structure and first sheet are advantageously fed to the press at the same feed rate. The apparatus includes driving means, preferably electric motors, for the first and second conveyors as well as the press.

[0057] Speed of the electric motor may be controlled by a control unit to synchronise speed of the first and second conveyors and the feed rate.

[0058] Electric motor(s) for controlling the speed of the conveyor portions of the press may be synchronised with first and second conveyor speed. However, once the core structure and first sheet have travelled past the feed end of the press, the press electric motor(s) may be controlled to a rate optimal for the bonding process. The conveyor portions of the press may include heater and/or cooler means to enable control over press temperature, again optimally for the bonding process. [0059] Reagent compositions, typically including reactants for forming a polymer resin, conveniently as an expanded foam, are conveniently injected by a reagent mixture delivery system located above the first conveyor proximate the feed end of the press.

[0060] The reagent composition delivery system may include one or a plurality of injection, spraying and/or pouring heads manually or automatically movable to selected locations for injection of reagent mixture to selected locations of the core structure. The plurality of injection heads may include a spare injection head as a backup, for example allowing maintenance of an injection head.

[0061] An automatic reagent composition delivery system may be controlled by a control unit to deliver reagent mixture delivery rate and deliver reagent composition from injection head(s) to the selected locations of the core structure.

[0062] The apparatus described herein may include a cutter for cutting insulated panels to size where operated continuously. However, the apparatus may be operated batchwise or semi-batchwise rather than continuously depending on the complexity of customisation of the core structure.

[0063] An insulated panel as produced in the above method or apparatus forms a further aspect of the present invention.

[0064] A product insulated panel may be a self-supporting building module for constructing a structure, for example as described in the Applicant’s co-pending Australian Provisional Patent Application No. 2017902629, filed 5 July 2017, the contents of which are hereby incorporated herein by reference.

[0065] A range of polymer resins may be used to form the core. Polyurethane and polyisocyanurate resins are particularly preferred with properties such as density and thermal and acoustic insulation properties being selected as required for the application in which product insulated panels are to be used. [0066] Reagent compositions to form such polymer resins are well known and include suitable alcohols and isocyanates, the latter also being suitable as a blowing agent causing the polymer to foam and/or form a cellular insulating structure.

BRIEF DESCRIPTION OF THE DRAWINGS

[0067] The method and apparatus for manufacturing an insulating panel may be more fully understood from the following description of preferred embodiments thereof made with reference to the accompanying drawings in which:

[0068] FIG. 1 is an orthogonal view of an apparatus for manufacturing an insulated panel according to one embodiment of the present invention.

[0069] FIG. 2 is a front orthogonal view of the apparatus of FIG. 1 during manufacture of an insulated panel according to the first embodiment of the present invention.

[0070] FIG. 3 is a top orthogonal view of the apparatus of FIGS. 1 and 2.

[0071] FIG. 4 is a front orthogonal view of the apparatus, similar to FIG. 2 but at a later stage in the manufacturing method.

[0072] FIG. 5 is a front view of the apparatus during the manufacturing method.

[0073] FIG. 6 is a front view of the apparatus, similar to FIG. 5 but at a slightly later stage in the manufacturing method.

[0074] FIG. 7 is a side section view of the first conveyor of the apparatus shown in FIGS. 1 to 6. [0075] FIG. 8 is a top orthogonal view of the apparatus of FIGS. 1 to 6 showing production of an insulated panel according to the first embodiment of the present invention.

[0076] FIG. 9 is a front orthogonal view showing the apparatus in similar production state to that illustrated in FIG. 7.

[0077] FIG. 10 is a side section view of the first conveyor of the apparatus shown in FIGS. 1 to 6, 8 and 9 following production of an insulated panel according to the first embodiment of the present invention.

[0078] FIG 11 is a top perspective view of the apparatus of FIGS. 1 to 6, 8 and 9 following production of an insulated panel according to the first embodiment of the present invention.

[0079] FIG. 12 is an orthogonal view of a core structure to form part of an insulated panel formed according to a second embodiment of the method of the present invention.

[0080] FIG. 13 is a first orthogonal view of an apparatus for manufacturing an insulated panel according to a third embodiment of the present invention.

[0081 ] FIG. 14 is a second orthogonal view of the apparatus of FIG. 13.

[0082] FIG. 15 is a partial top view of the apparatus of FIGS. 13 and 14 showing the press and first conveyor.

[0083] FIG. 16 is a side view of the apparatus of FIG. 14.

[0084] FIG. 17 is a detail from Fig. 14 showing the feed end of the press and the relative angular disposition of the first and second conveyors. [0085] FIG. 18 is a partial orthogonal view from above showing the feed end of the press, the first conveyor and the core structure portion of an insulated panel to be produced by the method and apparatus of the third embodiment of the present invention.

[0086] FIG. 19 is a detail from FIG. 11 showing a product insulated panel including accommodation for components to be included in the insulated panel in use.

[0087] FIG. 20 is a cutaway view of the product insulated panel of FIG. 19.

[0088] FIG. 21 is a detail of a product insulated panel similar to FIG. 19.

DESCRIPTION OF PREFERRED EMBODIMENT(S)

[0089] Referring first to FIGS. 1 to 11 , there are shown schematic views of an insulated panel manufacturing system 10 including a press 11 with upper and lower tracked conveyor portions 11 A and 11 B (each being traced and including a plurality of track elements 11C) spaced apart by a constricted zone 14 and having a feed end 11 a into which a first sheet 1 which may be of a lightweight cladding material, such as those exemplified below, though the material is not intended to be limiting, is continuously fed in a direction D1. Possible reagent compositions are described below.

[0090] The first sheet 1 is fed into the press 11 at the feed end 11 a and pushed or pulled through the press 11 , or through some other downstream pulling device (not shown), in a first direction D1 , towards the discharge end 115 where product insulated panels 50 can be collected, ready for use in construction of structures for example.

[0091 ] System 10 includes a table 20, located at one side of press 11 , for preparing a portion of an insulated panel or preform 18 with a core structure including structural frame 52 for use in a structure to be constructed from product insulating panels 50. Preform 18 is to be bonded to the first sheet 1 to form an insulated panel. Table 20 includes rollers 21 to ease movement of the second sheet 2.

[0092] The rollers 21 may be actuated manually or by an electric motor (not shown) to deliver the preform 18 in a direction D2 perpendicular to D1 as schematically indicated by Figs. 3 to 5.

[0093] Curable, foamable resin composition is first deposited, by metering or pouring onto the preform 18 by an injection system such as described below, before second sheet 2 closes over preform 18.

[0094] Press 11 applies pressure, and if necessary heat, through the upper and lower conveyor portions 11A and 11 B to assist bonding of the preform 18 to first sheet 1 through the curable foamable resin composition through a constricted zone 14 as schematically indicated in Figs. 7 and 8.

[0095] The pressure is controlled by operating hydraulic jacks 150 to position the structural beams 140 to cause a force to be exerted on upper conveyor portion 11 A and, consequently the preform 18, by the structural I beams 140 disposed across it and connected to upper conveyor portion 11 A by structural members 145.

[0096] Structural members 146 fix the lower conveyor portion 11 B to the floor.

[0097] The positioning of I beams 140 relative to lower conveyor portion 11 B also controls the dimension of constricted zone 14 and the degree of pressure applied.

[0098] An electronic control unit can be used to control position of the hydraulic jacks 150. [0099] The speed of upper and lower conveyor portions 11 A and 11 B is controlled by controlling the speed of the electric motors 116 actuating them.

[00100] The electric motor speed, typically synchronised between the two electric motors 116, is selected to optimise the production rate while ensuring that the requisite degree of bonding between preform 18 and first sheet 1 is achieved prior to the product insulated panel 50 discharging through the discharge end 115 of press 11 as schematically indicated by FIGS. 9 to 11.

[00101 ] The same electronic control unit as used for controlling the position of hydraulic jacks 150 and constricted zone 14 sizing may be used to control the speed of electric motors 116.

[00102] Referring to FIGS. 12 to 18, there is described a further embodiment of the method and apparatus of the invention which involves the insulated panel manufacturing system 110 which again includes a press 11 including upper and lower conveyor portions 11 A and 11 B, again being tracked and including a plurality of interconnected pivoting metallic track elements 11C. Pivoting of the track elements enables a substantially continuous surface to be maintained.

[00103] A first conveyor 100 is provided for feeding a preform including a core structure 118, the core structure 118 including a base sheet 1 of lightweight cladding material and structural frame 152 to form part of a structure constructed by a modular technique.

[00104] First conveyor 100 is disposed horizontally and feeds the core structure 118 towards the feed end 111 of the press 11.

[00105] Core structure 118 is pushed or pulled through the press 11 , or through some other downstream pulling device (not shown), in a first direction D1 , towards the discharge end 115 of the press 11 where product insulated panels 50 can be collected, ready for use in construction of structures for example. [00106] A second conveyor 200 is disposed above, and at an acute angle to, first conveyor 100. The acute angle is controlled by operating the hydraulic jacks 205 and 210 to heights corresponding to the required angle. Second conveyor 200 feeds a first sheet 2 to be bonded to the preform 118 through a polymer composition.

[00107] Both first and second conveyors 100 and 200 include rollers 121 , 221 to ease movement of preform 118 and bend first sheet 2 towards the press 11.

[00108] The rollers 121 , 221 are most conveniently actuated by electric motors (not shown) to deliver the preform 18 in the same direction and at the same speed or feed rate towards the feed end 111 of the press 11 as schematically indicated by Figs. 13 to 17.

[00109] Curable, foamable resin composition is first deposited onto the preform 118 as it travels along first conveyor 100. A reagent composition to form a curable, foamable polymer resin, for example as described below, can be deposited using a variety of types of dispensing equipment including types well- known in the art.

[00110] Suitable equipment includes, for example, a traversing hose, one or more stationary mix heads, one or more injection nozzles, or other suitable apparatus for dispensing a fluid.

[00111] As shown, insulated panel manufacturing system 110 includes a gantry 1150, here fixed but which could be movable, with two reagent composition injection heads 1152A and 1152B for spraying reagent composition to selected locations.

[00112] Gantry 1150 includes a manifold supplied with reagent composition, the manifold communicating with each injection head 1152A, 1152B through a duct 1152C. [00113] One injection head 1152B is operated by a control unit, to deposit reagent composition in selected location A of preform 118. Selected location A will require acoustic and thermal insulation when the product insulated panel 50 is in place within a structure constructed from a plurality of such panels 50.

[00114] Second injection head 1152A is here in back up mode, to be used when injection head 1152B is being maintained. However, both injection heads 1152A, 1152B could be operated simultaneously or in timed relation to each other at a rate selected with reference to the speed of first conveyor 100 and conveyor portions 11 A and 11 B. In any event, injection head 1152A is deliberately not operated to deposit reagent composition in location B which corresponds with a window for the final structure including panels 50. Insulation is not required in this location.

[00115] It will be understood that, though not shown, the equipment for depositing the curable, foamable resin composition may also include various tanks or other containers for storing components of the resin composition, metering means for metering those components and/or the formulated resin composition; mixing means for mixing the components to form the resin composition, pumping means for transferring the components of the resin composition from their respective storage containers to and through the mixing means and/or through the dispensing apparatus. Suitable equipment for mixing and dispensing the components of curable, foamable resin compositions are available commercially from, for example, Cannon, SAIP and Krauss Maffei.

[00116] If required, the dispensed resin composition may be formed into a layer and/or gauged at this point in the process using equipment such as, for example, a set of nip rolls or a doctor blade. It is not desirable for polymer resin to expand beyond the top of the preform 118 as this may lead to wastage and cost.

[00117] Resin composition sprayed or poured by injection heads 1152a and 1152B typically begins to react and expand as soon as it is deposited, and may be expanding in some cases even as it is deposited. Accordingly, foamable resin composition may already be partially expanded when sheet 2 is applied.

[00118] Application of sheet 2 to preform 118 and polymer resin is facilitated by the guide rollers 130 which guide, by bending, the sheet 2 towards the preform 118 and to ensure the correct tension is maintained in that sheet 2. As illustrated, for example, in Figure 14, the guide rollers 130 guide the sheet 2 such that the sheet 2 is applied generally from the first direction D1. In other words, the sheet 2 is applied from the first direction. That is, the sheet 2 is applied from the same direction as the sheet 1.

[00119] Although the first conveyor 100 and the second conveyor 200 are oriented with respect to each other at an acute angle, it will be appreciated that the sheet 2 is bent by the guide rollers 130 so that it contacts the preform 118 at an angle that is generally parallel to the first direction D1. In some embodiments, it may therefore be said that the sheet 2 is applied from the same direction as the sheet 1 , for at least this reason.

[00120] Slower-reacting resin compositions may not have expanded measurably at this point and, desirably, top sheet 2 may be brought under pressure by press 11 prior to resin composition expanding to contact it, making a more efficient bond.

[00121 ] As the assembly of preform 118 and sheet 2 travels through press 11 pressure, and if necessary heat, is applied through the upper and lower conveyor portions 11 A and 11 B to assist bonding of the preform 118 to first sheet 2 through the curable foamable resin composition through a constricted zone 14 as schematically indicated in Figs. 16 and 17. The pressure is controlled by operating hydraulic jacks 150 to position the structural beams 140 to cause a force to be exerted on upper conveyor portion 11 A and, consequently the preform 118, by the structural I beams 140 disposed across it and connected to upper conveyor portion 11 A by structural members 145. [00122] Structural members 146 fix the lower conveyor portion 11 B to the floor. The positioning of I beams 140 relative to lower conveyor portion 11B also controls the dimension of constricted zone 14 and the degree of pressure applied. An electronic control unit can be used to control position of the hydraulic jacks 150, I beams 140 and the applied pressure.

[00123] The expanded resin composition may be somewhat compressed in this step, but the pressure should not be so great as to collapse the polymer foam or to create a large back-pressure. Heat may be applied through either or both surfaces if needed to drive the cure of resin composition.

[00124] The speed of upper and lower conveyor portions 11 A and 11 B is controlled by controlling the speed of the electric motors (not shown) actuating them. The electric motor speed, typically synchronised between the two electric motors (not shown) is selected to optimise the production rate while ensuring that the requisite degree of bonding between preform 118, polymer resin and first sheet 2 is achieved prior to the product insulated panel 50 discharging through the discharge end 115 of press 11. The same electronic control unit as used for controlling the position of hydraulic jacks 150 and constricted zone 14 sizing may be used to control the speed of electric motors 116.

[00125] The assembly including preform 118, sheet 2, and resin composition is passed continuously through constricted region 14 that extends the length of press 11. This step is performed before foamable resin composition has fully expanded. Constricted region 14 has a height no greater than and preferably slightly (such as 2 to 25%) less than the combined height of the various layers immediately before they enter constricted region 14. Therefore, sheet 2 and resin composition 19 are compressed together in constricted zone 14 with pressure being controlled as described above.

[00126] Prior to applying sheet 2, resin composition is desirably only partially expanded and/or partially cured. Partial curing can help the expanding resin composition support the weight of sheet 2. The expansion can occur before, during and/or after sheet 2 is applied, as already described, though before application of sheet 2 is preferred.

[00127] The curing step typically proceeds simultaneously with the expansion and conveyor portion 11 A, 11 B should be controlled accordingly to synchronise this timing.

[00128] Quite often, particularly when resin composition is isocyanate-based, the generation of expanding gas and therefore the expansion step itself forms part of the curing reaction and in such a case will occur at least partially simultaneously with the curing step, although some additional curing reactions may continue after the blowing gas has been generated and the expansion has been completed.

[00129] The product insulated panel 50 is continuously expelled from the discharge end 115 of press 11. In the case of a structure, the product insulated panel 50 may have length of an entire wall section, for example being several metres in length and a few metres in width. Such a wall section can therefore be manufactured continuously reducing the number of panels in the wall section and reducing installation cost.

[00130] While the product insulated panel 50, as described here, is a pre-fabricated module to form part of a structure, laminate type structural insulated panels may also be produced by manufacturing system 110. Such laminated panels may then be cut to any desired length (such as by knife or, preferably a band or circular saw), post-cured if necessary or desirable, and packaged for warehousing and/or shipment.

[00131 ] Sheets 181 and sheet 2 each are single or multi-layer materials that may include at least one metallic layer or a layer of a refractory lightweight cladding material such as MgO or MgS04 board. [00132] If a metallic layer is selected, preferred metals for this purpose are steel, stainless steel, aluminium, nickel, zinc, titanium, bronze, copper, brass, magnesium, and various alloys of any of these.

[00133] Steel is most preferred on the basis of low cost and desirable mechanical properties. The metallic layer may be planar, but can also be profiled (for example, grooved or channelled along its length).

[00134] Product insulating panels 50 from manufacturing systems 10 or 110 are shown in FIGS. 19 to 21. Product insulated panels 50 may include a core structure 50 (as shown in FIGS. 19 and 20) or simply a polymer resin core as indicated in FIG. 21. Product insulation panels 50 preferably have a thickness of 80 to 250 mm. The foam layer may have a thickness from 70 to 240 mm.

[00135] Curable, foamable resin composition is a mixture of polymer precursors and blowing agents and/or blowing agent precursors that react in the process to produce a cellular polymer foam.

[00136] Curable, foamable resin composition preferably is formulated to produce a foam having a free rise density of a specified kg/m ³ , for example, within a range of 24 to 80 kg/m ³ , or a value of about 45 kg/m ³ . The cellular polymer foam so produced preferably is a rigid foam.

[00137] Isocyanate-based resin compositions may also be adopted because these compositions can be formulated to be low in initial viscosity and because isocyanate-based resin compositions can be formulated to expand and cure rapidly to form a polymer foam having useful properties.

[00138] The isocyanate-based resin compositions may be formulated to produce a polymer having urethane groups, urea groups and/or isocyanurate groups. [00139] An especially preferred type of isocyanate-based resin composition is a polyisocyanurate or polyurethane-polyisocyanurate foam-forming composition, as foams of these types exhibit an excellent combination of high thermal and acoustic insulation and excellent strength-to-weight ratio.

[00140] The product insulation panels 50 can be used in a variety of structural, thermal insulation and/or decorative applications. They can be used as materials of construction for interior or exterior walls, ceilings and roofing materials for buildings; as decorative and/or facade materials, ducting system panels, walls and ceilings in buildings; as thermal insulation panels for buildings and various types of cold-storage facilities.

[00141 ] The laminates can be used as deckings for ships and other transport vehicles. The product insulated panels 50 can in general be used in the same applications and in the same manner as conventional panels.

[00142] Overall reduction in total build time and total build costs is expected where insulated panels are fabricated as described above.

[00143] Modifications and variations to the method and apparatus for manufacturing an insulated panel may be apparent to skilled readers of this disclosure. Such modifications and variations are deemed within the scope of the present invention.

[00144] In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.