GB2216580A - A composite section frame element - Google Patents

Abstract

A composite section frame element for a window or door has an elongate extruded or moulded metal or plastics portion (13, 14) to which is attached a wooden or other material facing (12) so shaped that, when the element is incorporated into a frame structure the wooden or other material facing (12) is exposed on one face e.g. the interior of the frame substantially concealing the metal or plastics portion (13, 14) whilst it is itself substantially entirely protected by the latter from the other face of the frame. <IMAGE>

Description

A COMPOSITE SECTION FRAME ELEMENT The present invention relates generally to the construction industry, and particularly to the structure of frame elements intended to provide door and/or window frames. Such components are normally referred to as "joinery" elements since, traditionally, they have been constructed from wooden pieces joined together using carpenters' joints. Wooden frames for doors and windows have the advantage of being aesthetically attractive and offering excellent thermal insulation, but have the disadvantages that the wood itself is seriously attacked in moist conditions by wood boring beetles and wood eo rotting fungi. Such decay can be so extensive as to require complete replacement of the window or door frames after a relatively short service life.

Recent attempts to overcome the disadvantages of traditional wooden frames have involved the use of metal or plastics material frames. The metal normally used is aluminium or an aluminium alloy which can be extruded into a wide variety of sections, and the plastics material normally used is uPVC which, also, can be cast or extruded with complex cross-sectional shapes. Metal and plastics frame windows have the considerable advantage that the material is relatively resistant to the corroding and degrading effect of atmospheric agents and therefore require little or no maintenance during their service life: in particular metal and plastics window and door frames do not require routine painting to exclude moisture as was hithertofore necessary with the traditional wooden frames.Metal frames, however, suffer from the disadvantage that the metal used, aluminium, has a very high coefficient of thermal conductivity allowing rapid transfer of heat through those sections exposed to a temperature differential, such as that which frequently occurs across the walls and windows of internally heated buildings during the winter. Not only do such metal frames suffer from heat loss, but also from condensation rF at the relatively cool internal surfaces in contact with the warm more humid air within the interior of the building.

Additionally, metal and plastics window and door frames suffer from the disadvantage that they are not aesthetically as pleasing as wooden frames, Largely, it has been found that the use of natural materials in the domestic or working environment generally offers greater aesthetic satisfaction to the occupants than the use of a large amount of "artificial" materials, that is materials prepared by modern manufacturing techniques.

The present invention seeks, therefore, to provide frame elements suitable for use in the production of window and door frames which, by being of a composite construction, are able to offer the advantages previously available only from traditional wooden or metal or aluminium frames without suffering from the disadvantages encountered when using such frames.The composite frame element of the present invention, therefore, presents an external surface which is resistant to atmospheric agents, particularly moisture, whilst the frame as a whole does not suffer from a high thermal transmissivity and the parts thereof facing the interior of a building present surfaces which are composed of natural materials and are therefore aesthetically pleasing in themselves, whilst at the same time of being capable of accepting a paint finish allowing the occupant of the building to vary the internal decoration from time to time if desired.

According to one aspect of the present invention, therefore, a composite section frame element for a window or door frame of a building has an elongate extruded or moulded metal or plastics portion to which is secured a wooden or other material facing so shaped that, when the element is incorporated into a frame structure, the wood or other material facing is exposed on one face of the frame substantially concealing the metal or plastics portion whilst the wood is itself substantially entirely protected by the metal or plastics portion the face of which is exposed on the other face of the frame.

In use, therefore, the wooden or other natural material facing can be exposed to the interior of the building without being in any way exposed to the external atmospheric agents which in traditional wooden frames cause detrimental decay, whilst protecting the metal or plastics frame front exposure to the relatively higher temperatures within the building and thus insulating the frame against heat loss.

The metal or plastics component, exposed to the exterior environment, offers considerable resistance to degrading external agents and protects the internal facing of natural material against decay. The surfaces of the metal or plastics portion are, furthermore, capable of withstanding deterioration without requiring any outer coating of paint or other protective layer.

In a preferred embodiment of the invention the interior wooden or natural material facing is attached to the metal or plastics portion by a form-fitting interengagement. Conveniently the metal used for the frame element is aluminium or an aluminium alloy. In embodiments utilising plastics sections the plastics is preferably a uPVC.

In the preferred embodiment of the invention the form-fitting interengagement between the wooden or natural facing element or elements and the metal or plastics support is an elongate dovetail-like projection on one of the components which engages within a corresponding recess or channel on the other. It has been found preferable for the projection to be formed on the metal or plastics section whilst the recess or channel is formed on the wooden or natural material facing element.

Further, the shape of the metal or plastics sections can be such that openings allowing complete drainage pathways can be formed for allowing the escape of any moisture condensing within or infiltrating into the interior parts of the frame sections. Such openings may be formed in part in situ after installation of the frame, or may be preliminarily provided either at the factory or on site..

When forming a frame utilising frame elements as described hereinabove the ends of the elements are cut at an angle (bisecting the angle at which two adjacent frame elements meet) and the inclined face of the wooden or natural material portion exposed by this is secured to the corresponding exposed face on the adjacent frame member by an adhesive when the two members are joined together to form a frame.

The specific section or shape of individual frame elements may vary depending on the intended position within a window or door frame. It may be imagined, for example, that a typical window frame comprises an outer fixed frame separated into two openings or "lights", by a central mullion with the two lights being closed by respective sash or casement frames to which the glazing of the window is applied. The sash or casement is then attached to the fixed frame by hinges or slide coupling as appropriate.

The present invention also comprehends a composite frame for a door or window opening in which each frame limb is a composite structure having a wooden interior face portion and an exterior weatherproof portion made from a different material (that is a material other than wood) such as uPVC, aluminium or the like.

The present invention also comprehends a window or door frame having a frame element or frame limb as described hereinabove.

Also encompassed within the scope of the present invention is a building or edifice the openings in which are provided with frames constructed of composite frame elements in accordance with the invention as described above.

One embodiment of the present 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 a frame limb for constituting a main frame of a window; Figure 2 is a sectional view of a sash or casement frame limb; Figure 3 is a sectional view of a bead for retaining the glazing on a sash or casement frame limb as illustrated in Figure 2; and Figure 4 is a sectional view of a frame element suitable for forming a mullion separating two adjacent sash or casement frames formed from frame elements as illustrated in Figure 2.

Referring now to the drawings, the main frame element illustrated in Figure 1 is generally indicated with the reference numeral 11 and is composed of an extruded aluminium section to which is attached a main frame secondary element generally indicated with the reference numeral 12 which, as indicated by the shading, is composed of wood. The main frame primary element 11 of extruded aluminium has two main parallel webs 13, 14 which are joined at one end by a transversely extending face 15 and at the other by an internal transverse flange 16.

The transversely extending face 15 is joined at its edge opposite that spanning the main frame transversely extending face 15 to a parallel flange 17 which extends from the face 15 parallel to the main primary element web 13 and spaced therefrom by a distance D to define an interior space 18.

The main primary element web 13 has a web extension 19 coplanar therewith on the side of the transversely extending face 15 remote therefrom, which joins to an intermediate portion of an external exposed face element 21 which is also supported to the transversely extending face 15 by g secondary parallel web 20 lying parallel to the main web extension 19 to form a rectangular box section space 22 between the two parallel surfaces of the transversely extending face 15 and the external exposed face element 21 and the two supporting webs comprising the main web extension 19 and the secondary parallel web 20. The external exposed face element 21 is intended to be exposed on the exterior of a frame composed of frame limbs made from lengths of the main frame primary element 11 as will be described herein in more detail.

The internal transverse flange 16 projects, parallel to the transversely extending face 15 and the exposed external face 21 from the opposite ends of the main primary element webs 13, 14 and in the opposite direction from these webs. At its free end the internal transverse flange 16 has two L-section projections 22, 23 which together define a T-section channel 24 for receiving a resilient sealing strip. Close to its junction with the adjacent main primary element web 14 the internal transverse flange 16 has a small parallel ridge 25 which, together with the main primary element web 14 defines a small recess 26 the function of which will be described in more detail below.On the opposite face of the internal transverse flange 16 from that bearing the small parallel ridge 25 there are formed two inclined ribs 27, 28 which diverge from one another away from the internal transverse flange 16. These diverging ribs 27, 28 constitute a connector for the main frame secondary element 12 which, correspondingly, is formed with a dovetail section recess 29 having inclined side walls 30.

The main frame secondary element 12 is joined to the main frame primary element 11 by relative longitudinal displacement after having inserted the inclined ribs 27, 28 into the channel 29 at one end, and having been so connected the main frame secondary element is then securely fixed in position whilst working operations are performed on the composite frame elements so formed. As can be seen from the drawings the main frame secondary element 12 is generally L-shape, having a first limb 31 which extends into the space 18 and having flat parallel faces 32, 33, whilst the second limb 34 extends orthogonally therefrom and has a shaped face 35 directed away from the exposed face of the external exposed face element 21 and which, when the frame element 11 is made up into a frame is intended to face inwardly of a building.

When the composite frame element 11 is made into a frame the ends of each frame limb are cut at an inclination, for example of 45 degrees and the inclined end faces of the main frame secondary element 12 are secured together by adhesive whilst the inclined end faces of the various webs constituting the main frame primary element are abutted against one another and may or may not be secured by adhesive. In this way the relative connection of the main frame primary and secondary elements 11, 12 is secured and rendered permanent in the finished frame. As can be seen from Figure 1 the main frame element 11 is intended to fit with the parallel flange 17 abutting against the interior rebate or "reveal" of an opening in a wall 36.In this configuration the main primary element web 14 and its neighbouring internal transverse flange 16 define an L-shape recess for receiving a sash or casement composed of frame elements as illustrated in Figure 2. Referring now to Figure 2 there is shown a crosssection of a composite casement or sash element (referred to hereinafter as a sash element), generally indicated with the reference numeral 37 and composed of a primary sash element 38 made from extruded aluminium section having many features in common with the primary main frame element 11 as will be discussed hereinbelow, and a secondary sash element 39 which is almost identical to the secondary main frame element 12.Integers of the composite sash element which are the same as or serve similar purposes to corresponding integers of the main frame element described in relation to Figure 1 will hereinafter be identified with the same reference numerals raised by 200. Thus, it will be seen that the main frame primary element 38 is composed essentially of two parallel sash primary element webs 213, 214 joined at one end by a transversely extending face 215 which extends to one side of the main sash element web 213 and has, projecting therefrom, a flange 217 parallel to the main sash element web 213.At their other ends the main sash element webs 213, 214 are joined by a transversely extending internal flange 216 having two L-section ribs 222, 223 defining a T-section space 224 and a small parallel ridge 225 defining a small recess 226 exactly identical with the corresponding components of the main frame element of Figure 1. Likewise, on the opposite face of the internal transverse flange 216 are two diverging inclined ribs 227, 228 which form a dovetail connector for the secondary element 39 which, like the main frame secondary element 12 is provided with a dovetail recess 229 for this purpose. Likewise, the sash frame secondary element 39 is generally L-shape and has a first limb 231 with a flat face 232 and a second limb 234 with a shaped face 235. The first limb 231 fits into the interior space 218 between the parallel flange 217 and the main sash element web 213.

The sash frame element 38 differs from the main frame element 11, however, in that the exposed face 221 and the transversely extending face 215 extend beyond the plane defined by the parallel flange 217 and are joined at their remote ends by an inclined face 40 from which extends a lip 41 having an L-section with a T-section channel 42 for receiving a sealing strip.

The line C-C defines a plane parallel to the external exposed face 221 of the composite element 38 passing through the position of the sealing strip received in the T-section channel 42 and the transverse distance from this plane C-C to the shaped face 235 of the secondary sash element 39 is identified with the reference B. This distance is substantially the same as the transverse distance from the plane A-A passing through the location of the sealing strip in the channel 24 of the main frame and the plane including the front face of the external exposed surface element 21.When the composite element 38 is assembled to form a rectangular frame, such a frame can be dimensioned so as to fit within the frame defined by the main frame elements 11 with the face 235 of the secondary sash element 39 in contact with the sealing strip in the channel 24 and the exposed front face 21 contacted by the sealing strip in the channel 42. In such an arrangement it will be seen that the two secondary elements, namely the main frame secondary element 12 and the sash frame secondary element 39 both face inwardly and entirely conceal the metal of the primary elements 11, 38 whilst, on the outside of the frame, the metal primary elements 11, 38 both entirely cover the internal secondary elements and protect them from external atmospheric agencies.

Figure 3 illustrates a glazing bead for use in securing glazing, preferably a double glazing panel either to the main frame or to the sash frame as relevant. The glazing bead illustrated in Figure 3 is generally indicated with the reference numeral 43 and has an L-shape fixing limb 44 comprising a first limb portion 45 with a tapered free end 46 and a second limb portion 47 joined to the first limb portion and extending at approximately right angles with respect thereto. From the free end of the second limb portion 47 extends an inclined bridge element which joins the second limb portion 47 to an inclined face element 49 having a hooked nose 50 at one end.As illustrated in broken outline in Figure 2 the glazing bead 43 is located in position on the primary main frame element or the primary sash frame element by inserting the tapered free end portion 46 of the first limb portion 45 into the small recess 26 or 226 and engaging the hooked nose 50 under a ridge 51, 251 at the adjacent end of the exposed face 21, 221 respectively. A double glazing panel such as that indicated by the reference numeral 52 can thereby be retained in position between the internal transverse flange 16, 216 and the glazing bead 43.Assembly, of course, is readily achieved by fitting the double glazing panel 52 in position, engaging the seal in the channel 24, 224 and then introducing the first limb portion 45 of the bead 43 into the space between the edge of the glazing panel 52 and the secondary web 14, 214, introducing the tapered free end 46 of the first limb portion 45 into the recess 26 or 226 and then flexing the bead to snap-engage the hooked nose 50 under the lip 51, 251.

The glazing panel 52 and glazing bead 43 can be used on a frame composed of main frame elements 11 to form a fixed (that is, non-openable) window, or onto a frame composed of sash frame elements 37 to form an opening window which can then be secured by appropriate means into a fixed frame composed of frame elements 11. The sash frame may be secured so as to be slidable within the main frame or pivoted to the main frame as appropriate.

If a larger window opening is required than can conveniently be formed with a single rectangular frame, the mullion frame element generally indicated 53 in Figure 4 may be employed. This frame element may be used to separate a rectangular frame composed of main frame elements or; sash frame elements into two smaller openings by spanning two parallel such elements, and for this purpose the mullion frame element 53 comprises a generally box section member 54 comprising two main parallel webs 55, 56 joined at one end by an exposed face element 57 and at the other end by an inner face element 58 which extends as two flanges 59, 60 the opposite face of which bears respective pairs of inclined ribs 61, 62 serving the same purpose as the ribs 27, 28 of the main frame element or 227, 228 of the sash frame element.A mullion frame secondary member 63 is provided with two parallel dovetail channels 64, 65 by which the secondary element 63 is attached to the extruded aluminium section of the mullion frame. The flanges 59, 60 are equipped, like the flanges 16, 216, with small parallel ridges 425 defining spaces 426 for receiving the tapered end 46 of the fixing limb 45 of a glazing bead, and with L-section ridges 422, 423 defining a T-section channel 424 for receiving sealing strips which engage either against the internal face of the secondary member of a sash frame, or against the inner face of a double glazing panel depending on whether the mullion is used as a fixed frame for an opening light or for a non-opening light.

Openings may be formed at one or more of the points marked Oil O2 in Figure 1 or O3, O4 in Figure 2 to allow the escape pf any water within the sections which may have found its way iri by condensation or infiltration at the joints. In this way the build up of water within the sections can be avoided.

Claims (14)

1. A composite section frame element for a window or door frame of a building, comprising an elongate extruded or moulded metal or plastics portion to which is secured a wooden or other material facing so shaped that, when the element is incorporated into a frame structure, the wood or other material facing is exposed on one face of the frame substantially concealing the metal or plastics portion, whilst the wood is itself substantially entirely protected by the metal or plastics portion the face of which is exposed on the other face of the frame.

2. A composite section frame element as claimed in Claim 1, in which the interior wooden or other material facing is attached to the metal or plastics portion by a form-fitting interengagement.

3. A composite section frame element as claimed in Claim 1 or Claim 2, in which the metal used for the frame element is aluminium or an aluminium alloy.

4. A composite section frame element as claimed in any of Claims 1 to 3 in which, if used, the plastics sections are made from uPVC.

5. A composite section frame element as claimed in any of Claims 2 to 4, in which the form-fitting interengagement between the wooden or other material facing element or elements and the metal or plastics support is an elongate dovetail-like projection on one of the components which engages within a corresponding recess or channel in the other.

6. A composite section frame element as claimed in Claim 5 in which the said projection is formed on the metal or plastics section whilst the recess or channel is formed on the wooden or other material facing element.

7. A composite section frame element as claimed in Claim 5 or Claim 6, in which the dovetail-like projection is formed by two divergent elongate ribs projecting from one face of the component.

8. A composite section frame element as claimed in any of Claims 1 to 6, in which the shape of the metal or plastics sections is such that openings allowing complete drainage pathways are formed for allowing the escape of moisture condensing within or infiltrating into the interior parts of the frame sections.

9. A composite section frame element as claimed in any of Claims 5 to 8, in which the dovetail-like projection is formed on a limb of the said other component which lies at an (in cross-section) to the said limb constituting the said channel.

10. A composite section frame element as claimed in any preceding Claim, in which the said wooden or other material facing has an L-shape cross-section a first limb of which is received in a channel-like recess formed in one limb of the other component.

11. A composite section frame element substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

12. A window or door frame having a frame element or frame limb as claimed in any preceding Claim.

13. A composite frame for a door or window opening, in which each frame element is a composite structure having a wooden interior face portion and an exterior weatherproof portion made from a material other than wood.

14. A building or edifice the openings in which are provided with frames constructed of composite frame elements as claimed in any of Claims 1 to 9.