GB2345079A - Window frame suitable for supporting double glazed and curved panes - Google Patents

Abstract

A window frame construction formed from lengths [7] of plastics material, at least some of which are formed so as to support curved glass panes [2]. The frame is also arranged to accept double glazed panes [2]. In another embodiment, the window frame construction includes some plane glass panes which incorporate an opening sash or a vent. In a further embodiment, the parts of the frame intended to support a glass pane [2] have a fixing located on the frames' outer side for a glazing bead [10]. In a further embodiment, the window surfaces are arranged to support decorative features such as glazing bar components.

Description

WINDOW FRAME CONSTRUCTION This invention relates to a window frame construction. It relates in particular to a replacement window frame where the frame is formed of an extruded plastics material and in which the plastics profile is designed to accept double glazed glass panels.

A large number of houses built in the 1920 and 1930 years were provided with a'Suntrap' bay window that made a particularly attractive feature of the house aspect in a front elevation view. This window was very different from the usual bay windows available at that time because it included curved glass panes that gave the whole bay construction a somewhat convex appearance. These windows were intended to enable more daylight to enter the room behind the window and they were in keeping with the fashionable design forms of the period.

Ordinary bay windows having plane glass panels were of course easier and cheaper to make but the Suntrap bay window was considered a luxury feature that was fully compatible with the extemal design of the house.

The original Suntrap bay windows were made with metal frames but eventually these frames would suffer from deterioration and need to be replaced. Although steel replacement window frames are still available at the present time, these are only obtainable to suit single glazed windows. Because of a public demand for high quality window performance, there have been attempts to provide substitute frames but these were generally so unlike the original frames that the house frontal appearance could be spoiled.

Since there is now a great interest in preserving the original appearance of traditional houses in a street, there is a need to provide a Suntrap bay replacement window which will include all the technical features that one would expect in a modem window. These features include better draught proofing, improved hinge and lock construction, and the window and frame members being formed of a weather resistant material. A window frame and window that does not need to be painted regularly is also expected nowadays. The present invention was devised in an attempt to include some of these advantages.

According to the invention, there is provided a Suntrap bay window formed from plastics material moulded into profile shapes in order to support curved glass panels in which the glass panels are of double-glazed construction. The bay window may also include plane glass panels.

Preferably, the plastics frame material for each curved panel includes a glazing bead located on an outer side of the curve intended to support the glass panel.

Where the bay window includes plane glass panels, these may be arranged with opening sashes and vents.

The glass panes of the bay window may support glazing bars, these being provided so that the window will be similar in appearance to a traditional Suntrap bay window design.

The invention also comprises a Suntrap bay window formed according to the construction method of the present invention.

By way of example, some particular embodiments of the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is an elevational view of one design of Suntrap bay window, Figure 2 shows a second design of window, Figure 3 is a partial view of a horizontal cross-section through the window and frame construction, Figure 4 is a partial view in more detail of a horizontal cross-section through the window Figure 5 is a view similar to Figure 4 showing a window construction including a load bearing support, and, Figure 6 is a vertical cross-sectional view through the window and frame construction.

As shown in Figure 1, one model of Suntrap bay window 1 as viewed from the outside has the curved glass panels 2 located at the outer ends of the construction. In the centre, there are two plane opening windows 3 and a plane fixed window 4. The windows 3 are depicted with the usual imaginary diagonal lines in place to show the manner in which the hinges for the window opening action are placed. The glass panes of the window are fitted with horizontally located glazing bars 6 which are secured to the glass surfaces. These glazing bars 6 are a particular feature of the Suntrap bay window and they will generally be arranged so as not to conflict with the original design as fitted to the local 1930 style houses.

Figure 2 shows a second model of Suntrap bay window 1. In this embodiment, the centre portion of the bay accommodates three opening windows 3 and one fixed window 4.

Figure 3 is a simplified horizontal cross-section through the window showing the positions of the curved panels 2 with respect to the plane windows 3,4. The curved outline of the bay window will, of course, have a radius of curvatwe, a width and a height to match the brickwork opening in the building to which the window is to be fitted.

A more detailed partial horizontal cross-section is depicted in Figure 4. The curved panel 2 is seen to be supported between two vertical members 7 of plastics window frame material.

This material is supplied in lengths of extruded plastics composition having particular moulded profiles by specialist manufacturers. One manufacturer of a suitable profile material is Rehau Limited, Hill Court, Walford, Ross-on-Wye, Herefordshire HR9 5QN. The members 7 are of Standard 54 framing material and this is provided with a glazing bead 10 surface arranged to support the outer wall of the curved glass panel. At the upper end of the drawing Figure, the member 7 is secured to the building face through a layer 8 of packing material with a non-hardening mastic being used to seal both inner and outer edges of the material.

At the left hand side of the drawing Figure, the curved panel 2 is supported by two steel reinforced Standard 54 framing sections coupled together with a standard joining profile to form a post 9. The post 9 thus serves to link together each curved panel 2 and a fixed plane window 4. If a load bearing support is necessary, the joining profile is not used. Instead, as shown in Figure 5, a jacking assembly and pole 11 is inserted between the window elements.

This pole 11 is concealed by trim covers 12.

The plane windows 3,4 are standard double glazed window units.

The upper and lower edges of the curved panel 2 are secured respectively in a standard outer frame section 13 (Figure 6) and a standard outer frame section 14. It is of course necessary for the curvature of the plastics material of these framing sections to match the curved edge of the panel 2. The operation of forming the plastics material into the required curve is effected by a specialist plastics fabrication company.

The curved panel 2 is a double glazed sealed unit constructed of two sheets of 5mm thick clear glass separated by a 14mm wide air space. In the construction of this unit, the glass sheets are formed into a curved shape before being assembled into the sealed unit. The manufacture of the sealed unit is done by a specialist glass company and the techniques needed for this construction are already well-known.

The operation of securing the plane windows 3,4 and the curved panels 2 into the frame is completed by an external glazing technique. This may require the use of glazing clips, security tape or a silicone sealant.

A typical Suntrap bay window frame constructed by the aforementioned technique will have a height of 1500mm whilst the curved panels will be shaped to a radius of 552mm.

The glazing bars 6 are fitted to the required double glazed window units during manufacture. These items are standard aluminium glazing bars protected by a polyester powder coating and they are pre-shaped to fit the glass surface. The bars 6 are fitted to both the inner and outer glass panes or, in an alternative construction, to the inner and outer surfaces of the outer pane.

It will be noticed that the Figure 6 construction shows four horizontal glazing bars 6 whereas the windows of Figures 1 and 2 have only three glazing bars. The number and arrangement of these features will be adjusted to take into account the original fitted Suntrap window, the relevant house design and the designs of neighbouring houses.

The operation of constructing a replacement double-glazed Suntrap bay window is begun making a detailed survey of the proposed site and making notes of the required radius of curvature of the end segments of the bay. Alternatively, for obtaining the correct curvature, a template is constructed. The survey also involves measuring the overall window height and the positions of any horizontal glazing bars that may be required in the finished product. The template or measured radius details together with the overall height dimension is forwarded to a specialist plastics profile bending and fabricating company with instructions as to whether the information refers to the inside or the outside dimension of the segments and the position, size and type of plastics profile material which is to be used in the construction. It will also be necessary at this stage to specify the type of finish that the segments should be given since, due to their shapes, some of the operations required may cause problems if they are tackled without some modification of the standard equipment. The fabricating company will then proceed with forming the curved head and cill sections, cutting to size and welding to the other cut components and finishing the construction to the specified working standard.

A suitable glazing bead material will also be shaped to fit the curved frame section and this bead material is usually left slightly oversize for accurate fitting at a later stage. The plastics materials required for this construction are usually supplied to the fabrication company by the window manufacturer. The original survey will also have provided details for manufacture of the centre plane segment of the Suntrap bay window. This will be constructed as a standard plane window with reinforcement pieces being included to meet the profile suppliers specification and with additional reinforcement pieces being inserted in vertical frame members that connect to an adjacent segment. A computer-generated cutting sheet is created and from this the desired frame profile (s) will be mitre cut on a two head saw. Any transom/mullion will be double mitre cut to form a point at each end if a fully welded construction has been specified. In an alternative possible specification for the window, the transoms/mullions might be cut with square ends if mechanical joints are required. The cut material will then be marked up and drainage openings will be machined into the relevant sections. If a fully welded construction has been specified, further reinforcement pieces will be cut and the relevant pieces of profile will then be V-notched in readiness for the welding operation. The welding process is preferably performed on a multi-headed combination welding machine. This type of machine can weld a transom member into a frame member and frame to frame comers at the same time. If mechanical joints have been specified for the transoms/mullions, the necessary pieces of frame will have drainage openings machined into them and then reinforcement pieces will be inserted as specified prior to the welding operation. As the welding operation is of a simple four sided frame only at this stage, the welding can be performed on a small or a more basic welding machine. Once the pieces have been welded and the corners cleaned up, the square cut transoms/mullions can be endmilled with profile related cutters, assemble into the required frame shape with the necessary reinforcement pieces and then fixed in place mechanically with purpose made screws.

Any opening or dummy sashes can also be cut, prepared and welded. Once welded, the frames and sashes can be cleaned up, the gasket and bead fitted, and the fabrication is then completed ready for glazing. The welded joints may be finished in any one of three ways, grooved, raised pyramid or knifed flush and polished. The double-glazed units for the plane window can be ordered from sizes given on the computer print-out which will also supply a diagram of the required positions of any glazing bars. For the curved segments, however, it will be necessary to supply the frames to the company undertaking the glass bending operations to use as accurate templates. This company, generally, will be making the other plane units so they will already have the information to match through any glazing bar arrangement.

Once all the items are ready at least the curved segments should be trial glazed in the factory to ensure that the glass areas will fit with the chosen gaskets and beads. When considered satisfactory, the complete bay window can be taken to the site and installed. It is recommended that these windows should be fitted only by experienced fitters as otherwise there is a risk that the structural integrity of the building supporting the windows might be compromised.

In use of the window frame construction of the invention, the frame has been found to provide a satisfactory replacement for an original Suntrap bay window in a house. The use of modem materials in the construction means that the replacement frame can be an improvement on the original as regards draught proofing and the reduced maintenance requirement. The fitting of double glazed window units throughout the frame allows the construction to have a high degree of thermal insulation in order to meet modem expectations.

The frame construction of the invention is also capable of being adapted as regards the dimensions and arrangement of windows and glazing bars so that when used as a replacement window it will not be incompatible with the original 1930s house design. It will also ensure that where there exists a row of the 1930s houses, a replacement Suntrap bay window may be fitted without spoiling the overall traditional appearance of the street. The possibility of retaining such a feature is of considerable importance to many householders and local authorities.

The foregoing description of embodiments of the invention has been given by way of example only and a number of modifications may be made without departing from the scope of the invention as defined in the appended claims. For instance, it is not essential to use the particular plastics profile material, Standard 54, that has been specifically mentioned. There will be alternative profiles of the material that will be capable of doing a similar job.

Claims (7)

1. CLAIMS 1 A window frame construction for a Suntrap bay window, wherein which the frame is made from lengths of a plastics material moulded into profile shapes and where at least some of the lengths are formed suitably so as to be able to support curved glass panels, in which the frame is arranged to accept glass panels of a double glazed glass window construction.
2. 2 A window frame construction as claimed in Claim 1, in which the window frame is arranged additionally to include plane glass panels of a double glazed glass window construction.
3. 3 A construction as claimed in Claim 2, in which one or more of the plane glass panels includes an opening sash or vent.
4. 4 A window frame construction as claimed in any one of Claims 1 to 3, in which the plastics frame material parts intended to support a curved glass panel include a glazing bead fixing located on the outer side of a curved frame part intended to support the glass panel.
5. 5 A window frame construction an claimed in any one of Claims 1 to 4, in which the glass window surfaces are arranged to support decorative features such as glazing bar components.
6. 6 A window frame construction as claimed in any one of Claims 1 to 5, when including glass window panels.
7. 7 A window frame construction substantially as hereinbefore described with reference to any one of the accompanying drawings.