AU602625B2

AU602625B2 - Forming a window with a curved glazing bar

Info

Publication number: AU602625B2
Application number: AU29835/89A
Authority: AU
Inventors: Leslie Arthur Johns
Original assignee: A&L Windows Pty Ltd
Current assignee: A&L Windows Pty Ltd
Priority date: 1988-02-10
Filing date: 1989-02-10
Publication date: 1990-10-18
Anticipated expiration: 2009-02-10
Also published as: AU2983589A

Description

COLLISON for and on behalf of the Applicant).

Davies Collison, Melbourne and Canberra.

L i -t 1 li COMMONWEALTH OF AUSTR PATENTS ACT 1952 COMPLETE SPECIFICATION

ALIA

602 2 e (Original) FOR OFFICE USE Class Int. Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority: ,Riated Art: merndmaeni~ s mals under Se tionl 49 and is cor-icct for Il intiflg 00 0 Name of Applicant: SAddress of Applicant: A L WINDOWS PTY. LIMITED 8 Reid Street, Bayswater, 3153, in the State of Victoria, Commonwealth of Australia Actual Inventor(s): Address for Service: DAVIES COLLISON, Patent Attorneys, 1 Little Collins Street, Melbourne, 3000.

Complete specification for the invention entitled: M006&520 10 02 9 "IMPROVED WINDOWS The following statement is a full description of this invention, including the best method of performing it known to us 1 (ts tation required) Note, Initial all ulicrations, IAVII:S (OLLISON, MELBOURN' and CA RRA. i U I U rI I I i I~I~ r 0 04 o0 t 004 0 00 00 S0 0 0o o o 00 o 0 0 0 0 0 0 0 0 0 0 4 00 00 0 0 6 a4 4t f 0 0 0 a er~

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0040' IMPROVED WINDOWS The present invention relates to windows, which for the present purposes includes glazed doors, and is particularly concerned with windows with curved glazing bars.

5 The use of glazing bars in windows to provide a Georgian or colonial effect is well known.

Originally, the glazing bars were structural so that the bars intersected and supported the glass. Such glazing bars have been formed of wood, metal such as aluminium, and plastics. It has also been proposed to extrude nlastics glazing bars and adhere them to the surface of the glass so as to give a Georgian effect while, in fact, utilising a single sheet of glass. Generally two such glazing bars are provided opposite each other on respective surfaces of the glass.

The aforementioned imitations of Georgian i i 44 4( 44 44 44 4 44 44 44444 44 4 A l 4sl If 44 r windows have all proved generally satisfactory for straight glazing bars, but the Georgian period also included arched windows so that the upper edge of the glass was radiused. Glazing bars in the corresponding upper portion of the window reflected this radiused effect. Curved glazing bars are today particularly expensive to form of wood and while straight aluminium glazing bars, which may for example have been extruded, can be rolled into the desired radius, this is a costly and not commercially successful method of imitating the original effect.

In particular, curved aluminium glazing bars formed in this way would generally only be used in a structural manner, thereby substantially increasing the cost of the finished window.

It is an object of the present invention to alleviate this limitation of the prior art and there is accordingly provided a method of forming a window with a curved glazing bar which comprises heating an 20 elongate glazing bar to a plastic condition, introducing the plastic glazing bar to a mould having the desired curved shape, cooling the curved glazing bar, removing the curved glazing bar from the mould and bonding the curved glazing bar to the window.

Further according to the present invention there is provided a window when formed by the method described in the immediately preceding paragraph.

Generally two such curved glazing bars would be adhered to respective surfaces of the glass in opposed manner.

While the glazing bar may be formed of an appropriate metallic material or other material which softens on application of heat, it is preferred that it be of a thermoplastics material. Most preferably 4 PVC is used since it may have no memory.

Conveniently the elongate glazing bar is initially extruded in substantial lengths which may if necessary be cut to desired lengths prior to introducing the cut lengths to the curving mould.

Conveniently, the curving part of the method of the invention is performed on apparatus comprising a work top comprising a heat absorbing material with an upper surface having at least one groove formed therein, the at least one groove having a width substantially corresponding to that of the glazing bar and a curved portion having a radius identical to 0 the desired radius of curvature of the glazing bar, a o o displaceable shutter overlying part of the upper o 00 o0 0 15 surface and moveable so as to gradually overlie the 0o curved portion of the groove as the glazing bar is curved therein and heating means to heat the glazing bar to its plastic condition ahead of the shutter.

cboa O4 The work top may be formed entirely of the 000 20 heat absorbing material, for example aluminium, and may include a plurality of grooves having different 04 radii. The depth of each groove may be substantially equal to that of the glazing bar.

The displaceable shutter is advantageously tit 25 pivoted to the work top and is displaceable so as to K" overlie a substantial part of the groove immediately behind the portion of the groove into which the glazing bar is being plastically deformed at any one time. The shutter acts to retain the plastically deformed glazing bar in the groove as it cools, and may also assist cooling of the glazing bar if it is formed of a heat absorbing material such as steel or aluminium. Conveniently the groove includes an initial straight portion into which a leading end of the straight glazing bar is introduced and is held by the shutter. Heat is then applied to the adjacent portion of the glazing bar overlying the curved portion of the groove, and the heated portion of the glazing bar is fed into the curved portion of the groove as the shutter is displaced to overlie the heated portion.

The heating means advantageously comprises a hot air blower in the case where plastic deformation is achieved at a relatively low temperature, for oo example about 65 0 C for PVC. Means may be provided to guide the heating means a preselected distance from 0 o 4 0o the glazing bar and the same or different means are a 0conveniently provided to concentrate the heat from OP 15 the heating means onto the glazing bar. In one 4; 0 Co 0 embodiment the concentrator is a curved reflector plate which is supported from the blower and supports 0000the glazing bar as it is heated. Immediately behind °0 0 the concentrator the plastic glazing bar is permitted 04 6 o 20 to drop into the groove and the shutter is displaced 4 over the glazing bar immediately behind the concentrator.

The heating means and the shutter may be 4, displaced manually in which case they can be held 25 separately or the heating means may be supported by the shutter and the shutter can be displaced automatically.

The shutter should be in close contact with the upper surface of the work top, at least adjacent the groove, and may include a low friction bottom surface to facilitate the displacement.

The apparatus particularly facilitates the bending of profile sections having a relative substantial width and a relatively small height, in '7 a 6 the width plane.

One embodiment of a window formed in accordance with the present invention and apparatus for performing the method will now be described by way of example only with reference to the accompanying drawing in which: FIGURE 1 is a perspective sectional view of the window mounted in an appropriate frame; FIGURE 2 is a perspective view of part of the apparatus used for performing the method; and 000 FIGURE 3 is a plan view of the a~paratus of Figure 2 showing part of the glazing bar curved therein.

ao o qAn arched window pane 10 of part-circular 0000 oo 15 form shown in Figure 1 has a radiused outer edge 12 oQ and a straight bottom edge 14. The pane 10 may have 9 90 one or more straight radial glazing bars (not shown) extending, for example, from the centre of curvature 0000 o of the radiused outer edge 12 but has a curved S 20 glazing bar 16 on each of the inner and outer surfaces thereof. The glazing bars 16 have a radius 0 0 of curvature of approximately one half that of the outer edge 12.

Each glazing bar is formed of PVC and is S 25 extruded in the cross-section shown as part of a :i length of straight glazing bar. In order to curve the glazing bar as desired, the apparatus illustrated in Figures 2 and 3 may be used by which the straight *colonial bar length is heated until the PVC becomes plastic to be sufficiently workable to be deformed into a curved groove 54. The preferred heating temperature is about 65 0 C. Once the curved glazing bar formed in the groove 54 has cooled, it will retain its new shape and may then be readily bonded f; 0 o 003 0 0' a 0d 0 0 up 0 00 0 00 00 0 0 00 0000 00 Qo 0 001 004Z: 7 to the respective surface of the window pane 10 as desired. The second curved glazing bar 16 is bonded in opposite manner on the other surface of the pane so that the two glazing bars together give the appearance of intersecting the glass in a structural manner.

Most conveniently, the glazing bars have a substantially flat bottom surface and are bonded to the glass using silicon or other appropriate and well known bonding agent. Conveniently, an elongate groove may be provided in the bottom surface of the glazing bar to accommodate additional bonding agent in order to improve adhesion to the glass.

The apparatus 50 for curving the glazing bar 15 16 comprises a work top 52 formed of aluminium to act as a heat sink having two U-shaped grooves 54 formed in the upper surface 56 thereof of respective radius of curvature. Only the bases 58 of the U-shapes are curved, with the legs 60 being straight and parallel.

The grooves 54 have a shallow rectangular profile with the same overall width and height as the glazing bar 16 so that the glazing bar can fit snugly in the groove.

A substantially semi-circular shutter 62 is 25 pivoted on the work top at approximately the centre of curvature 64 of the curved grooves 54 and is formed of flat plate such as of steel so as to be relatively heavy. A liner (not shown) such as of hardboard may be bonded to the bottom surface of the shutter 62 so as to reduce scratching of the aluminium surface 56 of the work top 52 and possibly also to reduce friction. The shutter has a handle 66 at one end and has dimensions such that when it is rotated to a position where the curved periphery 68 i! is adjacent the same end 70 of the work top as the bases 58 of the grooves, the shutter overlies the whole curved portion of each groove.

In use, the shutter 62 is rotated clockwise from the position shown in Figure 2 so as to be entirely clear of the leading portion 72 of the respective groove. A leading portion 73 of the straight glazing bar 74 is then introduced into the leading portion 72 of the groove and the shutter 62 rotated anticlockwise so as to overlie that portion S, of the groove to clamp the leading portion 73 of the glazing bar as shown in Figure 2.

A hot air blower 76 supporting a guide 78 is +0 mounted on the shutter by an adjustable bracket 9o 15 immediately ahead of the straight periphery 77 of the shutter over the respective groove. The guide supports a portion of the glazing bar immediately ahead of the shutter and assists in guiding the 4444 o heated glazing bar portion into the groove. The 20 guide 78 acts as a concentrator of the heat from the 4 blower, and as the associated portion of the glazing 0 A bar becomes plastic the blower and guide are moved along the curved portion 58 of the groove and the heated portion drops into the groove. As this 25 happens the shutter 62 is displaced behind the blower and guide to retain the plastically deformed glazing bar in the groove as it cools, as shown in Figure 3.

Once the desired length of glazing bar has been plastically deformed and has cooled in the groove the shutter 62 is rotated out of the way and the arcuately radiused glazing bar can be removed, cut to the desired length and immediately bonded to the glass on site as the window is made up.

A novel method of supporting the pane of 1 9 glass 10 (with or without the glazing bars 16) is shown in Figure 1 in which both the curved and straight edges 12 and 14 of the pane 10 are supported in corresponding aluminium profiles 18 and 20. The profiles 18 and 20 have the same cross-section but clearly the profile 18 is curved along the same radius as the radius of curvature of the curved outer edge 12. The cross-section includes a first open box section 22 in which the glass pane 10 is supported and a second open box section 24 which abuts a reveal o 26 in the case of the bottom profile 20 but is spaced o o from side reveals 28 (one only shown) and a top reveal 30 in the case of the profile 18. A flange 32 n) o'0 on each of the profiles 18 an(' 20 abuts the edge face of the respective reveal 26, 28 and/or o The reveals 28 and 30 are straight, and a curved template 34 extends between the reveals as shown following the curve of the profile 18 with a o slightly larger radius of curvature so that the o 20 template 34 is spaced from the box section 24 of the profile 18 by, for example 10 mm, to receive plaster a board or other surface finishing material therebetween. The template may be formed of for exariple three ply timber having suitable o 25 flexibility. The template 34 is supported on an appropriately shaped gusset 36 extending between the reveals 28 and 30 and the template 34 and formed, for example, of chip board.

A second supporting gusset (not shown) may be carried by the open box section 24 of the curved profile 18 and project through the slot 38 thereof to support the template.

The reveals 28 are supported flush with corresponding studs 40 (one only shown) and the reveals 26, 28 and 30 are slightly recessed relative to the inner edge of the studs 40 and the corresponding lintels 42 so as to accommodate a plaster board or other finishing surface over the gusset 36.

Various modifications and variations may be made to the described embodiment of window and apparatus and all such modifications and variations should be considered as within the scope of the present invention. In particular, it will be o appreciated that the curved glazing bar could be formed by other means.

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Claims

2. A method according to Claim 1 in which the glazing bar is formed of a thermoplastics material.
3. A method according to Claim 2 in which the thermoplastics material is PVC.
4. A method according to any one of Claims 1 to 3 wherein cooling the curved glazing bar is performed by the mould acting as a heat sink. 4 4, A method according to any one of the preceding claims wherein the elongate glazing bar is heated to a plastic condition by means of a hot air blower. S6. A method according to any one of the preceding claims wherein the mould comprises an open curved groove to receive the heated glazing bar and a displaceable shutter is provided for retaining the glazing bar in the groove as it cools.
7. A method according to claim 6 wherein the means for heating the glazing bar carries means for guiding the heated glazing bar into the groove. I 12
8. A method of forming a window substantially as herein described with reference to the accompany drawings.
9. A window when formed by the method claimed in any one of the preceding claims. Apparatus for curving a glazing bar which comprises a work top comprising a beat absorbing material with an upper surface having at least one groove formed therein, the at least one groove having Sa width substantially corresponding to that of the r glazing bar and a curved portion having a radius identical to the desired radius of curvature of the glazing bar, ,a displaceable shutter overlying part of the upper surface and moveable so as to gradually overlie the curved portion of the groove as the 1 glazing bar is curved therein and heating means to I heat the glazing bar to its plastic condition ahead of the shutter.
11. Apparatus for curving a glazing bar substantially as herein described with reference to r Figures 2 and 3 of the accompanying drawings.
12. The steps or features disclosed herein or any combination thereof. DATED this 10th day of February 1989. A L WINDOWS PTY, LIMITED By its Patent Attorneys DAVIES COLLISON