GB2245300A - Architectural units eg for glazing - Google Patents

Abstract

This invention relates to architectural panels. and in particular edge encapsulated panels. To protect the encapsulating material (12) used, especially from ultra violet radiation, and strengthen the periphery of the panel, a frame comprising a plurality of rigid frame elements (14, 16), which, in the finished product, cover the major portion of the exterior surface of the edge encapsulation, is used as a mould for formation of the edge encapsulation and is secured to the edge encapsulation. The invention is especially applicable to encapsulated double glazing units (4). <IMAGE>

Description

ARCHITECTURAL UNIT The present invention relates to an architectural unit, and more particularly to an edge encapsulated architectural unit and method for producing the same. The term "edge encapsulation" refers to the setting of a liquid material in situ around the marginal periphery of an object.

UK patent GB 2 182 378B discusses the possibility of encapsulating the edge of a multiple glazing unit. By edge encapsulating the glazing unit, a hermetic seal is effected between facing sheets of the unit whilst simultaneously securing a spacer in position for maintaining the desired spacings between the sheets, and structurally bonding the sheets together. The edge encapsulation also functions as an architectural frame having a desired external configuration and decorative appearance.

However, an edge encapsulated unit of this type has a number of disadvantages. When used in buildings the glazed area is commonly at least lem2, and the unit must withstand the wind-loading forces in its working environment. Edge encapsulated glazings according to GB 2 182 378B may not have sufficient strength to withstand these forces. Also, although the polyurethane which is typically used as an encapsulating material withstands attack by water well, and also withstands attack by ultra-violet radiation well, when subject, in cycles, successively to water and ultra-violet radiation, the polyurethane tends to degrade shortening the life of the architectural panel. Further there is a potential problem of flame retardation; once a polyurethane is ignited it will sustain a flame.

The present invention aims to overcome these difficulties by providing a frame, comprising rigid frame elements, covering the major portion of the edge encapsulation which frame is used as a mould for the edge encapsulation and is secured to the encapsulating material.

According to the present invention, there is provided an architectural unit comprising a panel with a moulded-in place edge encapsulation encapsulating the marginal periphery of the panel, and a frame comprising a plurality of rigid frame elements covering the major portion of the exterior surface of the edge encapsulation wherein the frame is used as a mould for the edge encapsulation and is secured to the encapsulating material.

The invention also includes a method of producing an architectural unit which comprises providing a hollow section frame around the periphery of a panel with the peripheral edge of the panel extending into the hollow section of the frame, and seal means which together with the frame and the panel define a closed volume; holding the frame, seal means and panel in position relative to one another, introducing a settable liquid to substantially fill the closed volume, and setting the liquid to form a solid edge encapsulation and thereby secure the frame in place.

Optionally the panel may comprise a plurality of sheets, each of which may be monolithic or laminated. The sheets may be spaced to provide a multiple glazing module, especially a double glazing module.

The invention will now be described, by way of example only, with reference to the following drawings, in which: Figure 1 is a schematic plan view of an architectural panel according to the present invention.

Figure 2 is a cross-section on the line II-II of figure 1 drawn on an expanded scale.

Figure 3 is a schematic plan view of an assembly for producing architectural panels in accordance with the present invention.

Figure 4 is a cross-section on the line IV-IV in figure 3 drawn on an expanded scale.

Figure 5 is a schematic cross-sectional plan view of the corner area marked V in figure 3 at the level of the line marked V'-V' in figure 4 with the double glazing module omitted for clarity.

Figure 6 is a cross-section corresponding to Figure 4, of a sub-assembly produced in the process for building up the assembly shown in figure 3.

Figure 1 shows an architectural unit 2 having a plane panel 4 and a frame 6.

Figure 2 shows the plane panel 4 which is a flat double glazing module made up of two sheets of glass 8 and 9 separated by a spacer frame 10. In use the glass sheet 8 will be the interior sheet and the glass sheet 9 will be the exterior sheet.

This double glazing module is of the well known design with the spacer frame 10 inset from the peripheral edges 11 of the glass sheets 8 and 9. The plane panel 4 may be a double-glazing module (as shown) or may comprise any number of sheets e.g. a single monolithic sheet, a single laminated sheet or three separate sheets constituting a triple glazing unit; if desired glass sheets may be used, decorated or opacified; further, alternative sheet materials may be used in place of glass, for example, marble, plastics, stonework, stone laminates, metal or coated metal.

Around the marginal periphery of the double glazing module is an encapsulating material 12, which can be of any suitable material such as polyurethane (a material which sets by curing) or polyvinyl chloride (a thermoplastic material which is applied hot and sets on cooling). The variety of materials suitable for the various components of the present invention allow the invention to be used in a wide range of applications such as glazings, spandrels, wall panels and shower screens. Normally the panel will be a plane, i.e. flat, panel, but the invention is not limited to plane panels; for example, a curved shower screen may be produced in accordance with the present invention. It will be appreciated that this is most conveniently done when the edges of the panel are substantially co-planar.

The frame 6 comprises a rectangular interior sub-frame 14 and a rectangular exterior sub-frame 16, the exterior sub-frame 16 having an exterior face 17. The two sub-frames 14 and 16 are separated by a thermal break 18 to avoid a high thermal conductivity pathway from the exterior to the interior of the unit 2. The interior sub-frame 14 is made up of four rigid frame elements 14A, 14B, 14C and 14D; similarly the exterior sub-frame 16 is made up of four rigid frame elements 16A, 16B, 16C and 16D. Each of the individual frame elements 14 (A-D) and 16 (A-D) extends along one side of the plane panel 4. Thus there are a total of eight frame elements, four in each sub-frame. The frame elements 14 (A-D) and 16 (A-D) will normally be of metal, conveniently extruded metal e.g. aluminium or aluminium alloy sections, but other materials may also be used e.g. PVC.

Each of the frame elements 14 (A-D) and 16 (A-D) needs to be rigid i.e. self supporting prior to the edge encapsulation stage. Among the suitably rigid materials which may be used are aluminium, aluminium alloys and uPVC.

The sub-frames 14 and 16 extend inwardly past the peripheral edges of the glass sheets 8 and 9 to provide them with support, so that the frame elements extend to overlap the outer faces of the panel 4 on both sides thereof, providing protection for the edges of the panel. The edge encapsulating material extends under the frame elements to overlap the outer faces of the panel on both sides thereof and separates the sub-frames from the glass sheets 8 and 9 to avoid their damaging the glass sheets 8 and 9. The position of the sub-frames 14 and 16 may also ensure that the spacer 10 is substantially hidden from view; if necessary the spacer 10 can be coloured so that even when it is observed it does not detract from the overall appearance of the unit 2.

The sub-frames 14 and 16 are secured to the edge encapsulating material 12, either by the edge encapsulating material 12 bonding to the frame elements 14 (A-D) and 16 (A-D) and/or by the set edge encapsulating material 12 being sufficiently rigid to hold the sub-frames 14 and 16 in place by engaging around projections 20, some of which are of re-entrant form, on the sections forming the frame elements. The edge encapsulating material 12 also secures the plane panel 4 in place. Thus the frame elements 14 (A-D) and 16 (A-D), the plane panel 4 and the edge encapsulating material 12 are all maintained in position relative to one another.

As the sub-frames 14 and 16 are on the outside of the encapsulating material 12 they act as a protective 'skin'. This 'skin' protects the material 12 from the combined effects of water and ultra-violet radiation as well as protecting the material from flame and forming a barrier to air or oxygen required to support combustion. The normally visible faces of the sub-frames 14 and 16 can be treated (e.g. coloured) to enhance their aesthetic appearance.

The section used for exterior frame elements 16 (A-D) is provided with a first channel 22 and a second channel 24 opening on the peripheral edge of the unit. The first channel 22 is shaped to allow a weatherseal (not shown) to be inserted therein. In a typical architectural glazing structure the weatherseal will abut against a transom or a mullion. The second channel 24 is shaped to allow a hinge or a fixing such as a catch, strut or latch to be inserted thus providing the unit 2 with sufficient versatility to be used in a variety of applications. The channel 24 may also be employed to link adjacent units together, or to link the unit to a building.

The frame 6 need not be of the design exemplified above; this design merely serves to illustrate some of the advantages which may be obtained with an architectural unit according to the present invention. The frame may be adapted to provide means for many other functions and applications.

A method of manufacturing the architectural unit illustrated in figures 1 and 2 will now be described by way of example only.

The method may be regarded as comprising four steps: (1) Providing a plane panel.

(2) Preparing interior and exterior sub-frames.

(3) Mounting the sub-frames and plane panel in a jig.

(4) Edge encapsulating the plane panel.

The method will be described with reference to these four steps.

(1) In the first step, a rectangular plane panel 4 comprising in this case two opposed spaced glass sheets 8 and 9, separated by and adhered to a spacer frame 10 is assembled in known manner.

(2) A rectangular interior sub-frame 14 is built up of four rigid aluminium frame elements 14 (A-D), each mitred at its ends, and held together in the form of a rectangle using known aluminium corner keys. A rectangular exterior sub-frame 16 is similarly built up of four rigid aluminium frame elements 16 (A-D), each mitred at its ends, held together in the form of a rectangle using known aluminium corner keys. Typically the corner keys used comprise aluminium corner brackets which may be either pop rivetted onto the frame elements or glued into place using an industrial adhesive. The rigid frame elements 14 (A-D) and 16 (A-D) are extruded lengths of aluminium section, although other sufficiently rigid materials such as aluminium alloys and certain plastics (e.g. uPVC) may also be used.Each, or any, of the rigid frame elements 14 (A-D) and 16 (A-D) may be pre-treated on the surfaces which are to contact the edge encapsulating material 12 to increase (or if desired to decrease) the bonding between the edge encapsulating 12 material and the frame elements 14 (A-D) and 16 (A-D).

Two holes 50 are drilled in elements 16A and 16C of the sub-frame 16 as near to two opposing corners as possible without weakening the mitres (see figure 5) to serve as fill and vent holes. The holes 50 are drilled in the portion of the frame elements between the two channels 22 and 24 as explained below.

(3) In the third step, the sub-frames and plane panel are mounted in a jig assembly with the peripheral edge of the panel extending into the hollow section of the frame constituted by the two sub-frames (see Figure 4). A flat table 28 mounted on a pivot (not shown) is used to support the assembly. The pivot allows the flat table 28 to be set at a variety of angles to the horizontal e.g. to ensure the vent hole in sub-frame 16 is higher than the fill hole.

Referring to Figures 3, 4 and 5, four first jig elements 26 (A-D) of truncated U-section are fixably mounted on the flat table 28 to form a rectangle. At the corners of the rectangle the ends of the first jig elements 26 (A-D) are mitred where they abut against each other and further cut away at the corners where the fill and vent holes 50 will be located as further discussed below. A silicone seal 46 in the form of a strip is mounted in a slot in the upper face 47 of the inner limb of the U-section and extends the length of each jig element 26 (A-D) forming a continuous rectangular seal. A tapering projection 42 is provided on the upper face 49 of the outer limb of the U-section and similarly extends the length of jig element 26. The purpose of seal 46 and projection 42 are more fully described hereinafter.

The four first jig elements 26 are each held in place on the table 28 by a spaced pair of similar fixing means 30. The fixing means 30 each comprise a metal tongue 32, a metal post 34 and a threaded bolt 36 which engages a threaded bore in the table 28. The tongues 32 extend into recesses 38 in the first jig elements 26 and the bolts 36 are tightened so that the tongues engage against the lower surfaces of the recesses 38 and the upper surfaces of the posts 34.

The exterior sub-frame 16 is next located in the U-section openings in the first jig elements 26 which are shaped to receive it and have a smooth surface to avoid damaging the exterior face 17 (Figure 2) of exterior sub-frame 16. Four similar second jig elements 40, each of similar substantially rectangular cross-section, are then placed over the jig elements 26 around the exterior sub-frame 16. The second jig elements 40 have channels 44 in their lower faces 45 which extend the length of the second jig elements 40 and corresponding projections 42' on their upper surfaces 45'. The projections 42 of first jig elements 26 and the channels 44 of second jig elements 40 cooperate to locate the second jig elements 40 in position on first jig elements 26 abutting against the exterior sub-frame 16.

Second jig elements 40 are each mitred at one end and cut square at the other end so that, when assembled to form a rectangle, they produce closed mitred joins at one pair of opposite corners of the rectangle, but leave the sub-frame 16 exposed at the other pair of opposite corners for access to the fill and vent holes 50.

The plane panel 4 is then mounted over exterior sub-frame 16 as shown in Figure 4 with the peripheral edges of the panel 4 overlapping the sub-frame 16 on each side of the rectangle. The panel 4 rests on the silicone seal 46 which is provided to prevent the exterior glass sheet 9 touching the sub-frame 16, and also to seal the gap between sheet 9 and the sub-frame 16 during formation of the edge encapsulation. A silicone seal 46 is used because silicone does not adhere to the encapsulating material 12.

Referring again to Figure 4, a set of third jig elements 48 is provided each of truncated n-shaped hollow cross-section with a stepped upper face 49 " and a channel 44' in its lower face 49' and mitred at both ends. Each element 48 has two additional internal channels 51 in which are located silicone seals 53 and 55. Before the third jig elements 48 are located over second jig elements 40, they are inverted on a flat supporting surface in the form of a rectangle and the assembled interior sub-frame 14 fitted into the rectangular jig so formed to provide a sub-assembly of jig elements and sub-frame, one side of which is shown in cross section in Figure 6.The silicone seals 53 and 55 compressively hold the interior sub-frame 14 in place in the hollows of the third jig elements 48.Alternatively, or in addition, the interior sub-frame 14 may be held in place using a vacuum pump to create a reduced pressure between the interior sub-frame 14 and the third jig elements 48; other methods for holding the interior sub-frame 14 in place may also be used.

The sub-assembly made up of third jig elements 48 and interior sub-frame 14 is mounted over the second jig elements 40 with projections 42' on second jig elements 40 engaging in and locating channels 44' in third jig elements 48. The silicone seal 53 rests on the interior pane 8 of the plane panel 4 to seal the gap between the panel and the interior sub-frame. The silicone seal 55 bridges and seals the gap between the interior sub-frame 14 and the exterior sub-frame 16; this gap will become the thermal break in the final architectural unit.

As an alternative to using sub-frames with a silicone seal between them during the encapsulation stage, a continuous frame section may be used. In this case there is provided a frame section which extends completely from the interior to the exterior of the architectural unit 2 and which provides a continuous housing between silicone seals 46 and 53; a thermal break may then be produced after the encapsulation stage by removing a strip of the frame section in a manner well known in the art.

Figure 5 illustrates the arrangement of first and second jig elements 26 and 40 at the two opposing corners where the encapsulating material is to be injected and vented respectively (one corner is shown, the opposite corner is similar).

Figure 5 shows the second jig elements 40A and 40B cut square at their adjacent ends and exposing one corner of the sub-frame 16; the first jig elements 26A and 26B are mitred toward their inner edges at the corner and cut square toward their outer edges to similarly expose the corner of the sub-frame. The broken lines show the second jig element 40 extending beneath the exterior sub-frame 16. Thus, there is in effect only a partial mitre at the corners of the fill and vent holes to enable access to these holes. The silicone seals 46 must be continuous around the sub-frame 16, thus the first and second jig elements 26 and 40 are also continuous in the region of the seals 46. This arrangement allows access to the hole 50 which can be used as either a fill or vent hole.The hole 50 is drilled between the first and second channels 22 and 24 respectively, instead of in the exterior face 17, to avoid deleteriously affecting the exterior appearance of the unit 2.

Figure 5 also shows adjacent frame elements of exterior sub-frame 16 joined by a simple mitre, which is a convenient method of obtaining a perpendicular corner.

(4) It will be seen that sub-frames 14 and 16 (which constitute frame 6) with planar panel 4 and seals 46, 53 and 55 together define a closed volume 57 with fill and vent holes 50.

In this step, a settable edge encapsulating material is injected into the closed volume 57, and set.

Referring again to figure 4, pressure is applied, using G-clamps, to the upper surfaces 49" of the third jig elements 48 to hold jig elements 40 and 48 in place on jig elements 26 during the edge encapsulation process. Thus the jig elements 26, 40 and 48 are held in position by the force exerted by the G-clamps and by their co-operating projections and channels 42, 44 and 42' ,44' respectively. Additionally the first jig elements 26 are held by the tongues 32 as discussed above. The exterior sub-frame 16 is located on the suitably shaped lower interior surface of the first jig element 26 and held in position by the force exerted through the second jig element 40 (A-D) by the G-clamps.

The interior sub-frame 14 is compressively held between the silicone seals 53 and 55 and located against the interior surface of the third jig element 48. The glazing module is compressively held between silicone seals 46 and 53.

The flat table 28 is rotated to be vertical in such a way that the corner of the frame 6 adjacent the fill hole is the lowest part of the frame, and so that the corner of the frame adjacent the vent hole is the highest part of the frame. Thus, when the edge encapsulating material 12 is introduced it can displace the air within the closed volume 57 through the vent hole with the minimum disruption to the flow of the encapsulating material 12.

At this stage the edge encapsulating material 12 is introduced to fill the closed volume 57. when the air has been displaced from closed volume 57, the vent hole is plugged.

Typically the material 12 is introduced at a pressure from 0.1 to 3 atmospheres, although the assembly may be suitable for pressures up to about 10 atmospheres if held in place with sufficient force. The material 12 is then set. Typically, when a two component edge encapsulating material 12 is used, such as a polyol:isocyanate system, the setting is a curing process. The curing is simply an exothermic reaction between the two components. For a polyol:isocyanate encapsulating material 12 the assembly is left for between 10 and 20 minutes to allow curing and then the pressure is released from the upper surface 49" of the third jig element 48. The second and third jig elements, 40 and 48 respectively, are then removed and the edge encapsulated architectural unit 2 (in figures 1 and 2 and described above) extracted from the jig elements 26.

If necessary the small amount of edge encapsulating material 12 remaining from the fill and vent holes may be removed and the unit 2 washed. The unit 2 is then ready for use.

The following Example describes, by way of illustration only, the use of the method described above to produce an architectural double glazing unit in accordance with the invention.

EXAMPLE A double glazing module comprising two sheets of 6 mm float glass separated by and adhered to a 20 mm wide Tremco (Trade Mark) swiggle spacer frame giving a 20 mm air gap was provided and its peripheral glass surfaces treated to enhance the adhesion between the glass and the encapsulating material by wiping Betawipe (Trade Mark) VP 04604 and then priming with Betaprime (Trade Mark) 5001.

Interior and exterior sub-frames were then made up as described above, and the faces of the frame elements which would contact the edge encapsulating material were treated to enhance their adhesion to that material. The treatment comprised a two stage process which included a degreasing step and a priming step. The elements were wiped with a Betaclean 3100 (Trade Mark) degreaser and primed with Betaprime (Trade Mark) VP1706 (A & B) a two stage primer system.

All of the above treatment materials were obtained from Gurit-Essex (UK) Ltd. of 1B Gresham Road, Bermuda Ind. Estate, Nuneaton, Warwickshire, England. The materials were applied in accordance with the instructions supplied therewith.

Interior and exterior sub-frames 14, 16 were made up and mounted using jig elements 26,40 and 48 as described above with the table 28 horizontal.

The assembly was then secured using G-clamps acting against the underside of the table 28 and against the upper face 49 " of the stepped section on the third jig elements 49. Sufficient pressure was exerted to prevent escape of any encapsulating material past any of the silicone seals during the encapsulation process.

The jig elements were then heated by running hot water at 750C through water pipes (not shown)in contact with the jig elements. This heated the metal frame up sufficiently to avoid it inhibiting the exothermic reaction between the two components of the encapsulating material, thereby ensuring an even cure of the encapsulating components throughout the closed volume 57.

With the table pivotted at an angle to the horizontal as discussed above, an encapsulating material was injected into the closed volume 57 to edge encapsulate the double glazing module.

For the encapsulating system a two component polyol:isocyanate system comprising Polyol Hyperlast (Trade Mark) 7850442 and Isocyanate Hyperlast (Trade Mark) 21875/009 was used. Both these components were obtained from Macpherson Polymers Limited of Station Road, Birch Vale, Stockport, Cheshire, England. The two components, at ambient temperature, were mixed in a weight ratio of 4.5 polyol:1 isocyanate just before being pumped into the assembly. The mixture was pumped in at about 2 atmospheres of pressure. Because such low pressures are used (in edge encapsulation of vehicle windows using Reactive Injection Moulding pressures up to about 100 atmospheres are used) the components of the system can be manufactured to less exacting tolerances than those used in vehicle edge encapsulation processes.

Once filled the vent hole was plugged and the assembly was left for about 13 minutes before the table 28 was brought to the horizontal, the G-clamps were removed, the second and third jig elements were then removed. The encapsulated panel was extracted, cleaned and surplus material at the fill and vent holes removed. The panel was then ready for use.

Although the embodiments of the present invention specifically described herein involve the use of jig elements to surround the frame 6, the jig elements are not essential. Other methods may be employed to hold the components of the frame 6 in place. There are also occasions when no jig, or substitute for a jig, is required, for instance when using a frame section which provides a complete housing (as discussed above).

Claims (26)

Claims:

1. An architectural unit comprising a panel, a moulded-in-place edge encapsulation encapsulating the marginal periphery of the panel, and a frame comprising a plurality of rigid frame elements covering the major portion of the exterior surface of the edge encapsulation wherein the frame is used as a mould for the edge encapsulation and is secured to the encapsulating material.

2. An architectural unit according to claim 1 in which the panel is a glass sheet.

3. An architectural unit according to claim 1 in which the panel includes a plurality of sheets.

4. An architectural unit according to claim 3 in which the sheets are spaced from one another.

5. An architectural unit according to claim 3 or 4 which the panel is a double glazing module.

6. An architectural unit according to any preceding claim in which the panel includes a decorated glass sheet.

7. An architectural unit according to any preceding claim in which the panel includes a laminated sheet.

8. An architectural unit according to any preceding claim in which the panel includes an opaque sheet.

9. An architectural unit according to claim 8 in which the opaque sheet is metal or stone.

10. An architectural unit according to any preceding claim in which the frame includes projections into the edge encapsulation material.

11. An architectural unit according to any preceding claim in which the frame includes means for carrying a weatherseal.

12. An architectural unit according to any preceding claim in which the frame includes means for carrying a catch, hinge, strut, stay or latch, or for linking the unit to another unit or to a building.

13. An architectural unit according to any preceding claim in which the rigid frame elements are made of a metal or uPVC.

14. An architectural unit according to claim 13 in which the metal is aluminium or an aluminium alloy.

15. An architectural unit according to any preceding claim in which the frame elements extend to overlap the outer faces of the panel on both sides thereof.

16. An architectural unit according to any preceding claim in which the encapsulating material extends to overlap the outer faces of the panel on both sides thereof.

17. A method of producing an architectural unit which comprises providing a hollow section frame around the periphery of a panel with the peripheral edge of the panel extending into the hollow section of the frame, and seal means which together with the frame and the panel define a closed volume; holding the frame, seal means and panel in position relative to one another, introducing a settable liquid to substantially fill the closed volume; and setting the liquid to form a solid edge encapsulation and thereby secure the frame in place.

18. A method according to claim 17 in which the planar panel includes a plurality of sheets.

19. A method according to claim 18 in which the sheets are spaced from one another.

20. A method according to claim 18 or 19 in which the planar panel is a double glazing module.

21. A method according to any one of claims 17 to 20 in which the frame includes projections into the edge encapsulation material.

22. A method according to any one of claims 17 to 21 in which the liquid is introduced at a pressure of up to about 10 atmospheres.

23. A method according to claim 22 in which the liquid is introduced at a pressure of from 0.1 to 3 atmospheres.

24. A method of producing an architectural unit substantially as herein described in the Example with reference to figures 3 to 6 of the accompanying drawings.

25. An architectural unit produced by the method of any one of claims 17 to 24.

26. An architectural unit substantially as herein described with reference to and as illustrated in figures 1 and 2 of the accompanying drawings.