GB2227274A

GB2227274A - Double glazing extrusion

Info

Publication number: GB2227274A
Application number: GB8901040A
Authority: GB
Inventors: Han Seng Lee
Original assignee: TWINGLAZE Ltd
Current assignee: TWINGLAZE Ltd
Priority date: 1989-01-18
Filing date: 1989-01-18
Publication date: 1990-07-25
Also published as: GB8901040D0

Abstract

An extrusion for use in in situ double glazing, comprising a first elongate side having therein a first longitudinally extending groove 15 for locating a first strip of non-hardening sealant for sealing the extrusion to an existing pane of glass, a second elongate side opposite said first elongate side and having therein a second longitudinally extending groove 16 for locating a second strip of non-hardening sealant for sealing a second pane of glass to the extrusion in spaced relationship to said existing pane of glass, and a third elongate side generally transverse to said first and second elongate sides and defining an elongate slot for receiving and holding a limb 44 of a corner bracket for joining together a plurality of such extrusions to define a spacer frame. <IMAGE>

Description

Double Glazing This invention relates in general to in situ double glazing and more particularly to an extrusion for use in in situ double glazing, an in situ double glazing system, and a method of in situ double glazing.

Present day double glazing systems usually involve replacement windows and doors although in some cases secondary glazing is carried out in which a second window is installed on the inside of an existing window. Replacement windows are expensive and sometimes detract from the character of a building.

Known secondary glazing systems do not allow the cavity between the two windows to be evacuated of air and replaced by an inert gas.

Our corresponding British Patent Application No.8729533 seeks to mitigate these drawbacks, firstly by providing an extrusion for use in in situ double glazing, comprising a first elongate side having therein a first longitudinally extending groove for locating a first strip of non-hardening sealant for sealing the extrusion to an existing pane of glass, and a second elongate side opposite said first elongate side and having therein a second longitudinally extending groove for locating a second strip of non-hardening sealant for sealing a second pane of glass to the extrusion in spaced relationship to said existing pane of glass.

The invention of our co-pending Patent Application also provides an in situ double glazing system comprising a spacer frame assembled from one or more such extrusions, non-hardening sealant in said first and second grooves of the extrusion(s) sealing the spacer frame to an existing pane of glass and sealing a second pane of glass to the spacer frame, respectively.

Finally, the invention of our copending Patent Application provides a method of in situ double glazing, comprising the steps of: (a) assembling a spacer frame from one or more extrusions as defined hereinbefore; (b) locating non-hardening sealant in said first grooves of the extrusion(s) and applying the spacer frame to an existing pane of glass; (c) applying hardenable sealant between spacer frame and a frame of the existing pane of glass, (d) allowing hardenable sealant to harden, (e) locating non-hardening sealant in said second grooves of the extrusion(s) and applying a second pane of glass to the spacer frame, (f) applying further hardenable sealant between the edge of the second pane of glass and the frame of existing pane of glass, (g) allowing the further hardenable sealant to harden, (h) replacing air in cavity between the two panes of glass by inert gas.

Although the double glazing system of that copending Patent Application is a considerable improvement over prior art systems, we have now found that it is possible further to improve the system, in particular with regard to its performance in cold climates.

Accordingly the present invention provides, in a first aspect an extrusion for use in in situ double glazing, comprising a first elongate side having therein a first longitudinally extending groove for locating a first strip of non-hardening sealant for sealing the extrusion to an existing pane of glass, a second elongate side opposite said first elongate side and having therein a second longitudinally extending groove for locating a second strip of non-hardening sealant for sealing a second pane of glass to the extrusion in spaced relationship to said existing pane of glass, and a third elongate side generally transverse to said first and second elongate sides and defining an elongate slot for receiving and holding a limb of a corner bracket for joining together a plurality of such extrusions to define a spacer frame.

Preferably a region of the extrusion adjacent the slot is deformable to hold a said limb of a said corner bracket within said slot, although it is envisaged that other methods of holding could be employed e.g. by deforming a said limb of a said corner bracket within said slot.

Preferred and/or optional features of the first aspect of the invention are set forth in claims 2 to 9, inclusive.

In a second aspect, the invention provides an in situ double glazing system comprising a spacer frame assembled from a plurality of extrusions according to the first aspect of the invention, non-hardening sealant in said first and second grooves of the extrusions sealing the spacer frame to an existing pane of glass and sealing a second pane of glass to the spacer frame, respectively, and corner brackets received and held within respective elongate slots of the extrusions to join said extrusions to define the spacer frame.

Preferred and/or optional features of the second aspect of the invention are set forth in claims 12 to 15 inclusive.

In a third aspect, the invention provides a method of in situ double glazing, comprising the steps of: (a) assembling a spacer frame from a plurality of extrusions according to the first aspect of the invention by locating respective limbs of corner brackets within respective elongate slots of said extrusions and arranging for said limbs to be held within said slots; (b) locating non-hardening sealant in said first grooves of the extrusion(s) and applying the spacer frame to an existing pane of glass;; (c) applying hardenable sealant between spacer frame and a frame of the existing pane of glass, (d) allowing hardenable sealant to harden, (e) locating non-hardening sealant in said second grooves of the extrusion(s) and applying a second pane of glass to the spacer frame, (f) applying further hardenable sealant between the edge of the second pane of glass and the frame of existing pane of glass, (g) allowing the further hardenable sealant to harden, (h) replacing air in cavity between the two panes of glass by inert gas.

The invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a sectional view of one embodiment of an extrusion according to the first aspect of the invention, and Figure 2 is a fragmentary sectional view through a double glazing system according to a second aspect of the invention, on a smaller scale; and Figure 3 is a sectional view of a modification of the embodiment of Figure 1.

Referring firstly to Figure 1 of the drawings, the extrusion 10 shown therein is of generally rectangular cross-section having first, second, third and fourth elongate sides 11, 12, 13 and 14 respectively. The extrusion 10 is preferably formed of anodised aluminium.

The extrusion 10 has a first longitudinally extending groove 15 of generally arcuate cross-section in the first side 11 for locating a first strip of non-hardening sealant and a second longitudinally extending groove 16 also of generally arcuate cross-section in the second side 12 for locating a second strip of non-hardening sealant. It will be observed that grooves 15 is offset with respect to groove 16. The effect of this is to reduce the width of land 40.

The extrusion 10 also has an internal passage 17, extending longitudinally thereof.

A bevel 18 is provided between the first and third sides 11 and 13, respectively. Flanges 41 and 42 formed on the third side 13 define between them a generally T-shaped elongate slot 43 for receiving limbs of corner brackets one of which limbs is designated 44 in Figure 2 Minute longitudinally extending grooves 20 and 21 are provided in the second and fourth sides 12 and 14, respectively, to facilitate drill location when drilling holes through the extrusion to communicate with the passage 17.

Referring now to Figure 2 of the drawings, the double glazing system shown therein comprises a spacer frame 25 assembled from one or more extrusions 10, an existing pane of glass 26 mounted in a frame 27, non-hardening sealant 28 and 29 in the grooves 15 and 16, respectively, of the extrusion(s), a second pane of glass 30, hardenable sealant 31, and a packer 32.

The spacer frame 25 is assembled off site from parts cut to appropriate size from the extrusion(s) 10 and mitred at the corners. Generally L-shaped corner brackets having limbs 44 are located in respective slots 43 of extrusions 10 whereafter flanges 41, 42 are deformed in the region of limbs 44 to hold the limbs 44 securely within the slots 43. Appropriate holes 33, 34 (see Figure 1) are drilled in the spacer frame 25 between the second side 12 and the passage 17 and between the fourth side 14 and the passage 17 for air/gas exchange in the cavity 24 between the two panes of glass.

The non-hardening sealant 28 and 29 is, preferably, an inherently adhesive permanently elastic extruded butyl sealant strip, such as Butyl Hex 303 as sold by Perennator (Far East) Pte Ltd, of Jurong Industrial Estate, Singapore and the hardenable sealant 31 is, preferably, a structural silicone sealant. The packer 32 is, for example, expanded polystyrene.

The assembly sequence is as follows. First, the non-hardening sealant 28 is pressed into the groove 15 and the spacer frame 25 is pressed firmly and evenly against the inside surface of the existing pane of glass 26. Silicone sealant 31 is then applied, such as from a tube, between the spacer frame 25 and frame 27 of the existing pane of glass 26, the sealant 31 extending into the bevel 18 to improve the bite between the spacer frame 25 and the sealant 31. The sealant 31 is then left to harden for several days.

Non-hardening sealant 29 is then pressed into the groove 16 and setting blocks in the form of tubes are inserted into the holes 33 in the second side 12 of the spacer frame 25. The second pane of glass 30 is then pressed firmly and evenly against the sealant 29 in the groove 16. After inserting the packer 32 around the spacer frame 25 further hardenable sealant 35 is applied between the edge of the second pane of glass 30 and the frame 27, the sealant 35 covering or substantially covering the flange 19.

The sealant 35 is then allowed to harden for several days and during this hardening process the flange 19 indirectly supports the weight of the glass 30.

The air in the cavity 24 is then replaced by an inert gas, such as nitrogen, introduced at low pressure through holes 33, passage 17 and holes 34 at say the upper part of the spacer frame 25 and allowing air to escape through holes 34, passage 17 and holes 33 in say in lower part of the spacer frame 25. The holes 33 are then blocked off with hardenable silicone sealant.

Should the seals ever fail it is a relatively simple task to disassemble the system in situ and re-assemble it again after curing the defect, the second pane of glass 26 being removed by drilling out holes 33, cutting through the silicone sealant 35 and pumping air under pressure into the cavity 24.

The present invention provides a simpler method of spacer frame construction than does our previous proposal and, moreover, alleviates problems occurring in cold climates with our previous system.

Specifically, by off-setting groove 15 outwardly with respect to groove 16 the width of land 40 is reduced. The possibility of trapping moist air in the region between groove 15 and silicone sealant 31 is thereby reduced.

The embodiment of extrusion of Figure 3 is similar to that of Figure 1 except that a further chamfered surface 45 is provided. Once again this enables the amount of trapped moist air to be reduced.

The above embodiments are given by way of example only and various modifications will be apparent to persons skilled in the art without departing from the scope of the invention defined by the appended claims.

Claims

1. An extrusion for use in in situ double glazing, comprising a first elongate side having therein a first longitudinally extending groove for locating a first strip of non-hardening sealant for sealing the extrusion to an existing pane of glass, a second elongate side opposite said first elongate side and having therein a second longitudinally extending groove for locating a second strip of non-hardening sealant for sealing a second pane of glass to the extrusion in spaced relationship to said existing pane of glass, and a third elongate side generally transverse to said first and second elongate sides and defining an elongate slot for receiving and holding a limb of a corner bracket for joining together a plurality of such extrusions to define a spacer frame.

2. An extrusion as claimed in claim 1, wherein the region of the extrusion adjacent the slot is deformable to hold a said limb of a corner bracket within said slot.

3. An extrusion as claimed in claim 1 or claim 2, further comprising an internal passage extending longitudinally of the extrusion for allowing evacuation of the cavity between the two panes of glass by the provision of appropriate holes communicating the passage with the exterior of the extrusion.

4. An extrusion as claimed in any one of claims 1 to 3, wherein a bevel is provided at the edge of the first elongate side, in use, remote from the cavity between the two panes of glass.

5. An extrusion as claimed in any one of claims 1 to 4, wherein a bevel is provided at the edge of the first elongate side in use adjacent the cavity between the two panes of glass.

6. An extrusion as claimed in any one of the preceding claims, formed of aluminium.

7. An extrusion as claimed in claim 6, wherein the aluminium is anodised.

8. An extrusion as claimed in any one of claims 1 to 7, wherein the groove in the first elongate side is laterally offset relative to the groove in the second elongate side.

9. An extrusion as claimed in any one of claims 1 to 7, wherein the slot is generally T-shaped in cross-section.

10. An extrusion for use in in situ double glazing, substantially as hereinbefore described with reference to Figure 1 or Figure 2 of the accompanying drawings.

11. An in situ double glazing system comprising a spacer frame assembled from a plurality of extrusions as claimed in any one of the preceding claims, strips of non-hardening sealant in said first and second grooves of the extrusions sealing the spacer frame to an existing pane of glass and sealing a second pane of glass to the spacer frame, respectively and corner brackets received and held within respective elongate slots of the extrusions to join said extrusions to define the spacer frame.

12. A double glazing system as claimed in claim 11, wherein the cavity between the two panes of glass is evacuated of air and filled with an inert gas.

13. A double glazing system as claimed in claim 11 or claim 12, wherein a hardenable sealant is provided between the spacer frame and a frame of the existing pane of glass.

14. A double glazing system as claimed in claim 13, wherein the hardenable sealant encloses a packer.

15. A double glazing system as claimed in claim 13 or claim 14, wherein the extrusion(s) is/are as claimed in claim 4, and wherein the hardenable sealant extends into the bevel.

16. An in situ double glazing system substantially as hereinbefore described with reference to Figure 2 of the accompanying drawings.

17. A method of in situ double glazing, comprising the steps of: (a) assembling a spacer frame from a plurality of extrusions as claimed in any one of claims 1 to 10, by locating respective limbs of corner brackets within respective elongate slots of said extrusions and arranging for said limbs to be held within said slots;; (b) locating non-hardening sealant in said first grooves of the extrusion(s) and applying the spacer frame to an existing pane of glass, (c) applying hardenable sealant between spacer frame and a frame of the existing pane of glass, (d) allowing hardenable sealant to harden, (e) locating non-hardening sealant in said second grooves of the extrusion(s) and applying a second pane of glass to the spacer frame, (f) appying further hardenable sealant between the edge of the second pane of glass and the frame of existing pane of glass, (g) allowing the further hardenable sealant to harden, (h) replacing air in the cavity between the two panes of glass by inert gas.

18. A method according to claim 17 wherein the limbs are held within the slots by deforming the extrusions in the regions of the slots.

19. A method as claimed in claim 17 or 18, wherein a packer is interposed between the first-mentioned hardenable sealant and the further hardenable sealant.

20. A method of in situ double glazing, substantially as hereinbefore described with reference to the drawings.