IE980402A1 - Method and apparatus for manufacturing insulating panels - Google Patents

Abstract

A panel (1) comprises a profiled external skin (2), an internal backing tray (3) and an insulating core (4) which fills the space between the skin (2) and tray (3). A strip of reflective tape (11) is applied to the external skin (2). External skins (2) are overlapped, liquid foam reactants applied and a backing tray (3) is applied over the skins (2). The liquid foam reactants expand, on heating in an oven (50, 51) to form a foam insulating core. The backing tray (3) and foam core (4) are cut in a single cutting stage by leading cross cut saw (71) and a following blade (72). The corss cut saw (71) makes a first cut through backing tray (3) and the blade (72) cuts the foam core. The panels (1) are separated at the joint and then stacked for packing. <Fig. 11>

Description

The invention relates to a method and apparatus for manufacturing insulating panels of the type comprising a profiled external skin and an internal backing tray having an insulating core therebetween.

UK-A-2227712 and UK-A-2257086 describe methods and apparatus for manufacturing insulating panels. These methods are very efficient in use, however, there is an increasing need to improve the manufacturing efficiency to cut costs and maximise the production of such insulating panels.

This invention is therefore directed towards providing an improved method and apparatus for efficient manufacturing of insulating panels.

Statements of Invention According to the invention there is provided a method for manufacturing an insulating panel of the type comprising a first skin and a second skin having an insulating core therebetween, the method comprising the steps of:conveying a first skin along a flat bed with the outer surface of the skin lowermost; applying liquid insulating foam reactants onto the first skin; leading a second skin over the first skin to form an assembly; heating the assembly in an oven to allow the liquid foam reactants to between the first and second skins; and < automatically cutting the second skin and foam core at a preset location of the panel, the cutting means comprising a leading cutting means and a trailing cutting means, the leading cutting means cutting through the second skin to define a first cut and the trailing cutting means travelling in the first cut for cutting of the foam core.

Preferably, the second skin and foam core are cut by automatically driving a cutting means across the assembly as the assembly is travelling along a cutting bed. Preferably, the leading cutting means is a cross-out circular saw for cutting through the second skin and at least part of the foam core to define the first cut. Preferably, the trailing blade extends into the first cut to cut the foam core. In one embodiment of the invention the blade is movable from a rest position to a cutting position.

In this case preferably the blade is biassed into a normally rest position by a biassing means, the blade being movable into the cutting position against the biassing of the biassing means, during cutting. Most preferably the blade is pivotally movable between the rest and cutting positions.

In one embodiment, the method includes the steps of automatically driving the trailing blade towards the internal face of the first skin in accordance with the profile of the first skin to cut the foam through to the internal face of the first skin. Most preferably, the method includes the step of vibrating the trailing blade as it is driven through the first cut defined by the leading saw.

According to the invention there is provided an apparatus for manufacturing an insulating panel comprising:IE 980402 means for conveying a first skin with an outer surface of the skin lowermost; foam applicator means for applying liquid foam reactants to the first skin; means for leading a second skin over the first skin to form an assembly; an oven for heating the assembly to allow the liquid foam reactants to expand to form an insulating core between the skins; cutting means for automatically cutting the second skin and foam core at a preset location of the panel, the cutting means comprising a leading cutting means for cutting through the second skin to define a first cut and a trailing cutting means travelling in the first cut for cutting of the foam core.

Ideally, the apparatus includes a cutting bed along which the assembly is led and mounting means for mounting the cutting means to travel with the assembly along the cutting bed as the cutting means cuts the second skin and foam core. In one arrangement, the cutting means comprises a leading saw and a trailing blade mounted to and travelling across the assembly with the leading saw. Preferably, the leading saw is a cross cut saw. In a preferred embodiment the blade is movable from a normally rest position to a cutting trailing position. Preferably the apparatus includes biassing means for biassing the blade into the normally rest position, the blade being moved into the cutting trailing position against the biassing of the biassing means, during cutting. Ideally, the biassing means is a spring means. In a preferred arrangement the blade is pivotally mounted for movement between the normally rest position and the cutting trailing position.

In one arrangement, the apparatus includes vibrating means for vibrating the trailing blade as it travels through the cut made by the leading saw.

The apparatus may include biassing means for Massing the trailing blade into a raised position. Typically, the apparatus includes ram means for driving the trailing blade against the biassing of the biassing means to cut the foam through to the internal face of the first skin. Ideally, the apparatus includes means for detecting the profile of the first skin, and means for operating the ram means to drive the blade downwardly to follow the profile of the first skin.

The invention also provides insulated panels whenever manufactured by a method of the invention and/or using an apparatus of the invention.

Brief Description of the Drawings The invention will be more clearly understood from the following description thereof given by way of example only with reference to the accompanying drawings, in which:20 Fig. 1 is a flow chart of the method of the invention; Fig. 2 is a perspective view of a reflective tape applicator used in the method; Fig. 3 is a side view of the reflective tape applicator; Fig. 4 is a perspective view of a jointing tape applicator used in the method of the invention; Figs. 5(a) to 5(c) are end elevational views of the jointing tape applicator of Fig. 4, in use; Fig. 6 is a perspective view of an oven with a spacer changeover apparatus used in the method of the invention; Fig. 7 is an end cross sectional view of part of the spacer changeover apparatus; Fig. 8 is a perspective view of a part of a cutting means used in the method of the invention; Fig. 9 is another perspective view of the cutting means part of Fig. 8; Fig. 10 is a perspective view of the cutting means in use; Fig. 11 is a side elevational view illustrating the operation of the cutting means; Fig. 12 is a perspective view of a protective material applicator used in the method of the invention; Fig. 13 is a side view of the protective material applicator of Fig. 12; Fig. 14 is a side view of a stack of panels with a protective material therebetween; Fig. 15 is a side, partially cross sectional view of a panel breaker apparatus used in the method of the invention in a first position of use; Fig. 16 is a side view of the breaker apparatus of Fig. 15 in a second position of use; Fig. 17 is a side view of the breaker apparatus of Fig. 15 in a final position of use; Figs. 18(a) and 18(b) are side, partially cross sectional views of panels separated using the apparatus of Fig. 15 to 17; and Fig. 19 is a cross sectional view of a typical panel formed using the method and apparatus of the invention.

Detailed Description of the Invention Referring to the drawings, the method and apparatus of the invention is for forming an insulated panel of the type which is illustrated in Fig. 19 and indicated generally by the reference numeral 1. The panel 1 comprises a profiled extemai skin 2 of steel or aluminium material, an internal backing tray 3 also of steel or aluminium material and an insulating core 4 of polyurethane or polyisocyanurate foam material which fills the space between the extemai skin 2 and backing tray 3. The insulated panel 1 is typically used for roofing and/or cladding systems, adjacent panels being overlapped both longitudinally and transversely to clad and/or roof a particular area.

Referring particularly to Fig. 1, the method according to the invention for forming the panel 1 in a substantially continuous manner comprises the step A of leading a sheet of extemai skin material from a reel onto a flat bed with the outermost face of the extemai skin 2 lowermost. Reflective tape is applied in step B to the extemai skin 2 at a desired location as will be described in more detail below. The desired longitudinal overlap between adjacent panels are automatically marked using an ink jet apparatus. The extemai skin 2 is then profiled at C and cut to length in step D. The trailing edge of the extemai skin 2 of a first leading panel in the line is lifted up and placed down on the leading edge portion of the following extemai skin 2 in step E. As will be described in more detail below, a joint between the extemai skins 2 is made by automatically applying a jointing tape at F. The extemai skins 2 are then preheated at G prior to application of liquid foam reactants at H.

A sheet of backing tray material is led from a reel in step I, profiled in step J, and preheated in step K. The profiled backing tray 3 is then continuously applied over the overlapped external skins 2 and liquid foam reactants in step L. As the backing tray 3 is applied, a longitudinally extending side sealing tape 5 is also applied at M between the backing tray 3 and the external skin 2 to confine the foam core 4 in the desired space.

The backing tray 3 is maintained in spaced-apart relationship from the external skin 2 by appropriately sized spacer blocks. The spacer blocks may be readily changed as described in more detail below by first opening an oven in step N and changing the blocks in step 0.

The liquid foam reactants are then allowed to expand to fill the space between the external skin 2 and backing tray 3 by passing the assembly through the oven in step P in which the reactants are heated and allowed to expand to the desired thickness of foam insulating core 4.

The output from the oven is a continuous longitudinal sheet of insulating panels 1 interconnected by the jointing tape. As will be described in more detail below, at the joint between adjacent external skins, the backing tray 3 and foam core 4 are cut in a single cutting stage through to the internal (or upper) face of the external skin 2 in step Q. A protective material is applied to the exposed face of the backing tray 3 in step R and adjacent panels 1 are separated at the joint in step S in preparation for stacking and packaging.

Referring particularly to Figs. 2 and 3, there is illustrated a reflective tape applicator 10 used in the method of the invention for applying a length of reflective tape 11 to a desired location, typically adjacent a side edge, of the external skin 2. The reflective tape 16 is led from a supply reel 12 over guide wheels 13 to a grooved index wheel 14 and on to an applicator head 15. A desired length of tape 16 is drawn from the supply reel by an indexing ram 20 carrying a rack 21 which engages with a pinion 21 of the index wheel 14 to deliver the tape to the applicator head 15. The tape 16 may be applied in different lengths to initiate particular processing parameters. Typically, the indexing ram 20 is operated once to deliver a length of tape 16 for a right hand panel and may be operated twice to deliver a double length of tape 16 to indicate a left hand panel.

The tape 16 is held in place on the applicator head 15 by suction. The applicator head 15 is driven by a cutting and applicator ram 25 from an initial rest position (Fig. 3) to receive reflective tape, through an intermediate position against a blade 26 to cut the tape to length, to a final tape applying position (Fig. 2) in which the cut tape is applied to the external skin 2. When the length of tape 11 is applied, the ram 25 is released and the process is repeated to apply a length of tape 11 at desired locations of the external skin 2.

The length of reflective tape 11 applied to the upper face of the external skin 2 is used to automatically actuate various further steps in the method of the invention. It may be used, for example, to automatically activate the cutting means for cutting the backing tray and foam core through to ±e external skin. It may also be used to automatically activate the breaking means to separate the cut panels at the joint. In addition, the reflective tape 11 may trigger the operation of the jointing tape applying apparatus described below and/or the protective material applicator which is also described below.

Alternatively coding means may be provided by means other than a reflective tape. The coding means may, for example be or include a bar code which may be applied to a tape or possibly directly to a skin.

Referring particularly to Figs. 4 and 5, there is illustrated an automatic jointing tape applicator 30 used in the method of the invention to apply a jointing tape at the joint between adjacent external skins 2. Jointing tape 32 is led from a supply reel 31 to a guide 33. Gripper jaws 34 are then used to grip the free end of the tape 32 and to draw it across the bed on which the profiled extemai skin is travelling. The length of the jointing tape 32 drawn across the bed is longer than the width of the skin 2 to take account of the profile of the skin 2.

The length of tape 32 is then drawn under an applicator head 35 which has a number of sections 36 corresponding to the flat portions of the profile of the extemai skin 2 and a number of sections 37 corresponding to the corrugations of the extemai skin 2. The applicator head 35 is moved up and down by a ram 39 and the outer two of the head sections 36 may be moved in and out by a second ram (not shown).

As the tape 32 is drawn under the applicator head 35, it is cut to length by engaging against a blade 40. The outer two applicator head sections 36 are then moved from the outer position illustrated in Fig. 5(a) to the inner position illustrated in Fig. 5(b) to form the tape 32 into loops in the region of the corrugations. The ram 39 is then operated to drive the applicator head 35 downwardly to apply the jointing tape 32 across the profile of the extemai skins 2 at the overlapped joint between adjacent skins 2 as illustrated in Fig. 5(c).

The tape 32 is maintained in position on the applicator head sections 36 by suction.

The line of extemai skins 2 is not stopped while the jointing operation takes place as the applicator 30 is mounted on a carriage 40 which travels with the line to optimise production efficiency.

The jointing tape applicator 30 may be automatically operated when the reflective tape described above is detected by a suitable detector.

Referring particularly to Figs. 6 and 7, in the method of the invention the assembly of the external skin 2, backing tray 3 and liquid foam reactants are heated in a long oven having a top bed 50 and a bottom bed 51. During the heating process the spacing between the backing tray 3 and external skin 2 is maintained by a continuous course of spacer blocks (not shown) on both sides. The top bed 50 is maintained at the desired spaced position from the bottom bed 51 by a plurality of first spacers 52 which are each interposed on rods 53 interconnecting the top and bottom oven beds 50, 51. The top bed 51 is lifted up from the bottom bed 50 by lifting rams 54. io A quick safe changeover from one thickness of panel to another is effected by lifting up the top bed 51 on operation of the rams 54 and changing over to second spacers 55 which in this case are thicker than the first spacers 52.

The spacers 52 are each mounted on a spacer arm 56. The top bed 51 is lifted up from the bottom bed 50 by operating the rams 54. The spacer arms 56 are then pushed out by pusher rams. Each spacer arm 56 is pivotally mounted at 57 for rotation from a first position in which the first spacer 52 is between the beds 50, 51 through 180° to a second position in which the first spacer 52 is removed and the second spacer 55 is in position between the beds 50, 51.

All of the spacer arms 56 may be rotated substantially at the same time by operating a single or a number of spacer arm rotating rams 59. A ram 59 rotates the arm 56 through a rack 60 and pinion 61 arrangement.

The pusher rams are then reversed to push the second spacers 55 into position before closing down the top bed 51 of the oven on operation of retraction of the main rams 54.

Referring particularly to Fig. 8 to 11, cutting means 70 for cutting the backing tray 3 and foam core 4 at the joint between overlapping skins 2 comprises a leading cutting means provided by a cross cut saw 71 and a following blade 72. The blade 72 is operated against the biassing of a spring 74. The blade 72 is pivotally mounted by a pivot pin 77 on a bracket 75 which is in turn mounted to the housing 76 of the cross cut saw 71 so that the blade 72 travels across following the cross cut saw 71. The blade 72 is angled forwardly in the rest position and is held in that position by the spring 74. As the blade 72 is moved across, it is angled back and joggled up and down to provide a clean cutting action.

The cross cut saw 71 is set so that the cutting edge is spaced above the upper face of the flat surface of the external skin 2. The blade 72 is set so that as it moves across its cutting edge just engages the foam core.

As will be particularly apparent from Fig. 11, when the joint between external skins is detected, particularly using the reflective tape as described above, the cutting means 70 is automatically operated to cut the backing tray 3 and foam core 4. The cross cut saw 71 makes a first cut in which the blade 72 travels to cut through the core providing, in a very efficient way, a relatively clean cut.

For maximum processing efficiency, the cutting means 70 is mounted on a carriage (not shown) which travels with the panel as it progresses along the line.

A detector may be used to detect the position of the corrugations of the external skin as the blade 72 travels across. When a corrugation is detected, a ram may be operated to drive the blade 72 down to engage the corrugation and to cut the foam core 4 in the corrugation through to the upper face of the external skin. The blade 72 may also be vibrated by a vibrating means (not shown) to provide a clean cut.

Referring particularly to Figs. 12 and 13, there is illustrated a protective material applicator means 80 used in the method of the invention . The applicator means 80 in this case comprises three nozzles 81 which are mounted on and spaced-apart across a carriage 82 above the upper face of the backing tray 3 of the panels 1.

Each of the nozzles 81 is supplied with a flowable protective material through individual supply pipes 83. On detection of the reflective tape applied as described above, the protective material is automatically applied in a number of blobs 85 at spaced locations along and across the panels 1. The blobs 85 of protective material harden to provide spacers 86 between adjacent panels 1 when they are stacked as illustrated in Fig. 10 for storage and transportation. In this way, damage to the surface of the panels is substantially prevented.

In this case, the protective material is a hot melt adhesive which is prepared from io granules stored in a storage vessel and delivered on demand to a heater which melts the material into a flowable form which is then delivered along the pipes 83 to the nozzles 81. The hot melt adhesive cures rapidly in ambient conditions to form the panel spacers 86.

Referring to Figs. 15 to 17, there is illustrated a panel breaking apparatus 90 used in the method of the invention for separating a leading panel 91 from a trailing panel 92 at the cut joint 93. A first clamp comprising a first upper clamping head 94 and a first lower clamping head 95 grips the leading panel 91. A second clamp comprising a second upper clamping head 96 and a second lower clamping head 97 grips the trailing panel 91. The first and second clamps are mounted on separate carriages 98, 99 which are moved apart from the position illustrated in Figs. 15 and 16 to the separated position illustrated in Fig. 17 to separate the adjacent panels 91, 92 at the joint from the joined position illustrated in Fig. 18(a) to the separated position illustrated in Fig. 18(b).

The carriages 98, 99 each comprise a post 101, 102 which is fixed relative to the respective panel 91, 92 and a movable post 103, 104. The posts 101, 103 and 102, 104 are interconnected by pivot arms 105, 106 and the posts 101, 102, 103, 104 are also interconnected by respective rams 107, 108. To engage the upper clamp head 94, 96 with the adjacent panels 91, 92, the rams 107, 108 are operated from the raised release position illustrated in Fig. 15 to move the posts 103, 104 on the pivot arms 105, 106 to the extended engaged position illustrated in Figs. 16 and 17. The lower clamps 95, 97 are also operated by lower rams, not shown.

At least the leading clamp may be provided with a roller 110 on a guide arm 111 pivotally connected to the movable post 104 and movable by a guide ram 112. The roller 110 rides on the surface of the backing tray 3 of the panel 91 to position the upper clamps 94, 96 as short a distance as possible above the backing tray. In this way, the distance through which the upper clamp heads 94, 96 travel is minimised. Consequently, the speed of the panel separation process is optimised.

It will be noted that the lower clamp heads 95 and 97 are spaced in the release position illustrated in Fig. 15 below the lower surface of the panels 91, 92. This ensures that grit and dirt are not trapped which could lead to damage to the exposed surface of the panel.

The carriages 98, 99 on which the clamps are mounted travel with the panels as they progress along the production line. This is important in ensuring that processing time is optimised as the panels are not stopped during the separation process.

The separating apparatus may be automatically actuated by a suitable detector picking up the reflective tape applied as described above.

It will also be appreciated that the breaker means may include a blade means to provide a smooth cut of the foam core through to the lower skin, on operation of the breaking means, e.g. on operation of the clamping means and/or on application of the separation force.

The invention provides a highly optimised and efficient method and apparatus for manufacturing insulating panels.

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

Claims (23)

1. A method for manufacturing an insulating panel of the type comprising a first skin and a second skin having an insulating core therebetween, the method comprising the steps of:conveying a first skin along a flat bed with the outer surface of the skin lowermost; applying liquid insulating foam reactants onto the first skin; leading a second skin over the external skin to form an assembly; heating the assembly in an oven to allow the liquid foam reactants to expand to form an insulating core between the skins; and automatically cutting the second skin and foam core at a preset location of the panel, the cutting means comprising a leading cutting means and a trailing cutting means, the leading cutting means cutting through the second skin to define a first cut and the trailing cutting means travelling in the first cut for cutting of the foam core.

2. A method as claimed in claim 1 wherein the second skin and foam core are cut by automatically driving a cutting means across the assembly as the assembly is travelling along a cutting bed.

3. A method as claimed in claim 1 or 2 wherein the leading cutting means is a cross-out circular saw for cutting through the second skin and at least part of the foam core to define the first cut.

4. A method as claimed in any preceding claim wherein the trailing cutting means is a blade that extends into the first cut.

5. A method as claimed in claim 4 wherein the blade is movable from a rest position to a cutting position.

6. A method as claimed in claim 5 wherein the blade is biassed into a normally rest position by a biassing means, the blade being movable into the cutting position against the biassing of the biassing means, during cutting.

7. A method as claimed in claim 5 or 6 wherein the blade is pivotally movable between the rest and cutting positions.

8. A method as claimed in any claims 4 to 7 including the steps of automatically driving the trailing blade towards the internal face of the first skin in accordance with the profile of the first skin to cut the foam through to the internal face of the first skin.

9. A method as claimed in claim 8 including the steps of biassing the trailing blade into a normally raised position and driving the trailing blade downwardly against the biassing in accordance with the profile of the first skin.

10. A method as claimed in any of claims 4 to 9 wherein the method includes the step of vibrating the trailing blade as it is driven through the first cut defined by the leading saw.

11. A method as claimed in any of claims 1 to 10 wherein the first skin is a profiled external skin and the second skin is an internal backing tray.

12. A method for manufacturing an insulating panel as claimed in any of claims 1 to 11 substantially as hereinbefore described with reference to the accompanying drawings. 5

13. Apparatus for manufacturing an insulating panel comprising:means for conveying a first skin with an outer surface of the skin lowermost; 10 foam applicator means for applying liquid foam reactants to the first skin; means for leading a second skin over the first skin to form an assembly; an oven for heating the assembly to allow the liquid foam reactants to expand to form an insulating core between the skins; cutting means for automatically cutting the second skin and foam 20 core at a preset location of the panel, the cutting means comprising a leading cutting means for cutting through the second skin to define a first cut and a trailing cutting means travelling in the first cut for cutting of the foam core. 25

14. Apparatus as claimed in claim 13 including a cutting bed along which the assembly is led and mounting means for mounting the cutting means to travel with the assembly along the cutting bed as the cutting means cuts the second skin and foam core.

15. Apparatus as claimed in claim 13 or 14 wherein the cutting means comprises a leading saw and a trailing blade mounted to and travelling across the assembly with the leading saw. 5

16. Apparatus as claimed in claim 15 wherein the leading saw is a cross cut saw.

17. Apparatus as claimed in claim 15 or 16 wherein the blade is movable from a normally rest position to a cutting trailing position. io

18. Apparatus as claimed in claim 17 including biassing means for biassing the blade into the normally rest position, the blade being moved into the cutting trailing position against the biassing of the biassing means, during cutting.

19. Apparatus as claimed in claim 18 wherein the biassing means is a spring means.

20. Apparatus as claimed in any of claims 17 to 19 wherein the blade is 20 pivotally mounted for movement between the normally rest position and the cutting trailing position.

21. Apparatus as claimed in any of claims 15 to 20 including vibrating means for vibrating the blade as it travels through the cut made by the leading 25 saw.

22. Apparatus as claimed in any of claims 15 to 21 wherein the apparatus includes 'biassing means for biassing the trailing blade into a raised position.

23. 5 24. 25. 26. 27. Apparatus as claimed in claim 22 wherein the apparatus includes ram means for driving the trailing blade against the biassing of the biassing means to cut the foam through to the internal face of the first skin. Apparatus as claimed in claim 22 or 23 including means for detecting the profile of the first skin, and means for operating the ram means to drive the blade downwardly to follow the profile of the first skin. Apparatus as claimed in any of claims 13 to 24 wherein the first skin is a profiled external skin and the second skin is an internal backing tray. Apparatus for manufacturing an insulating panel as claimed in any of claims 13 to 25 substantially as hereinbefore described with reference to the accompanying drawings. An insulating panel wherever manufactured by a method as claimed in any of claims 1 to 12 and/or using an apparatus as claimed in any of claims 13