GB2077337A - Window and the like frames - Google Patents

Abstract

A frame member 10a for a movable light and a frame member 10b for a fixed light are both formed from the same u.p.v.c. extrusion 14. Each has an abutment surface 22, one for receiving glazing 40 and the other for receiving a movable frame member 12. In both lights, the glazing 40 is secured by an identical snap-fit clip 42. A method of forming the frames is also described, in which the hollow extrusions are filled with a foamed plastics material in a jig to enable a thinner-walled extrusion to be used. Also described is a method of joining the extruded members at the corners of the rectangular frame. <IMAGE>

Description

SPECIFICATION Window and the like frames This invention relates to frames for windows and similar framed constructions such as doors or the like, in buildings. The term "window" is to be construed as including such constructions.

In recent years window frames made from extruded sections of polyvinyl chloride (p.v.c.) have been growing in popularity. They require no painting, and little or no maintenance, and are much less liable to warp as compared with conventional timber window frames. On the other hand, they offer greater thermal insulation as compared with aluminium window frames.

One aspect of the present invention provides one or more window frames having a hinged movable light and a fixed light, the fixed light comprising glazing received against an abutment surface of a first fixed frame member, the abutment surface being generally parallel to the plane of the frame, the movable light comprising a movable frame member which when hinged into the closed position is received against the abutment surface of a second fixed frame member which has substantially the same cross-section as the first fixed frame member.

Preferably the abutment surfaces are provided with a resilient sealing strip to seat against the glazing or the movable frame member respectively. Preferably the fixed light has a clip attached to the first fixed frame member to hold the glazing against the abutment surface thereof.

The movable frame member may also have an abutment surface for receiving glazing, which is held thereagainst by a clip of the same crosssection as the clip on the fixed light. In a composite window frame having both a fixed and a movable light, the first and the second fixed frame members may be butt-jointed, and various measures may be taken to prevent ingress of moisture at the joint.

A second aspect of the present invention provides a method of making a frame for a window or the like in buildings, comprising taking an elongate hollow plastics frame member, placing it in a jig which supports the plastics material of the member against internal pressure therein, and filling it with a foamed plastics material. Suitably the foamed plastics material is foamed in situ within the frame member. The foamed plastics material gives greater strength and rigidity to the hollow frame member, so that the hollow frame member can be made from thinner gauge material. The use of the jig prevents the thin plastics material of the hollow member from distorting or bowing outwardly under the exothermic heat and pressure of the foamed plastics material.Without the jig, thicker plastics material would be needed for the follow frame member and the frame produced would be more expensive as a result.

The invention also includes window or like frames made by the above method.

Preferably the frame is made up from at least four lengths of such frame members, joined together at their ends to form a rectangular frame.

In a preferred method according to the invention, the lengths are secured together after the filling with the foamed plastics material. This may be done by routing out the foamed plastics material at the end of the member so as to form a recess, and inserting in the recesses of two adjacent frame members a securing insert which joins the two adjacent frame members in the desired abutting relationship.

A third aspect of the invention provides a window or like frame comprising a main frame having at an outer edge thereof for juxtaposition with a wall in which the frame is to be mounted, a subsidiary frame member which is more resilient than the main frame. The subsidiary frame member can then give way somewhat if subsidence should occur. The subsidiary frame member is suitably hollow.

Window frames according to the invention will now be described by way of example, with reference to the accompanying drawings, wherein: Fig. 1 is a front view of two abutting frames, Fig. 2 is a cross-section through part of one of the frames, on the line A-A of Fig. 1, Fig. 3 is a partly cross-sectional, partly outline view through parts of the two frames on the line B-B in Fig. 1, Fig. 4 is a partly sectional exploded view of a corner joint of one of the frames, Figs. 5 and 6 are cross-sections on the lines D-D and E-E in Fig. 1, showing alternative jambs, and Fig. 7 is a cross-section through a jig used in the manufacture of the frame.

Seen in Fig. 1 are two fixed frames 1 0a, 1 Ob.

An outwardly opening casement frame 12 is hinged in the frame 1 Oa. The frames 1 0a, 1 Ob and 12 are each formed from four lengths 13 which are extruded from unplastised polyvinyl chloride (u.p.v.c.) and mitred at the corners as will be described below. Surrounding the frames 1 Oa, 1 Ob there is shown a buckframe for fitting the frames into an aperture in a building, formed from four hollow extruded lengths 16 of u.p.v.c.

As seen in Fig. 2, the lengths 14 of the frames 1 0a, lOb, 12 are filled with a rigid polyurethane foam 58 expanded to a density of about 20 to 25 Ibs/cu. ft. (320-400 kg/m3). The foaming is carried out in situ in the u.p.v.c. extrusion, before it is cut and mitred into the lengths 14. The foaming is carried out in a jig which conforms to the exterior shape of the extrusion and provides support against the heat and pressure generated during foaming.Referring to Fig. 7, the jig is in two halves 78, 78', each comprising an outwardly opening elongate steel channel section 80, 80', to which is welded an elongate depending steel plate 82, 82'. The channel 80 of one half 78 and the plate 82' of the other half 78' are hinged together by a plurality of hinges 84 spaced along the length of the jig. When the two halves 78, 78' are hinged into the closed position seen in Fig. 7, they can be clamped together by clamps (not shown) at their ends, and they enclose a rectangular cross-section cavity 86. Two aluminium formers 88, 90 are located in opposing relationship in the cavity 86.

Those shown in Fig. 7 are intended to conform substantially to the exterior shape of one of the lengths 14 of the casement frame 12, but alternative formers can be used for the lengths 14 of the frames 1 Oa, Ob.

In use, the formers 88, 90 and frame member 14 are loaded in between the two halves 78, 78' of the jig, which are then hinged closed and clamped together, with suitable end plates in position. The polyurethane material is then injected from one end. We have had good results injecting the foaming material at 28 Ibs/in2 (about 1.9 to 2.0 kg/cm2). The supporting jig prevents the lengths 14 undergoing any distortion or bowing as a result of the foaming process.

As seen in Fig. 2, the cross-sections of the extrusions 14 for the fixed frame 1 Oa are generally L-shaped, while those of the casement frame 12 are generally T-shaped. The L shape of the extrusion 14 of the frame 1 Oa provides an abutment surface 22 towards which the frame 12 hinges about a hinge axis 24 (the hinges themselves not being in the drawings). The abutment surface 22 is provided with a longitudinal groove 26 in which a soft polyvinyl chloride sealing strip 28 is a press fit, secured by a solvent-based adhesive. When the casement frame 12 is in the closed position as shown in Fig. 2, its bears against this trip 28 so as to make the window frame weatherproof.The sealing strip 28 is on the interior side of a cavity 30 between the frames 1 Oa and 12, and a narrow gap 32 is left at the exterior side of this cavity 30 between the frames 1 Oa and 12 when the frame 12 is in the closed position. Thus, if there is a wind blowing there will be some movement of air through the gap 32 into or out of the chamber 30, with actual pressure changes experienced inside the chamber 30 being much smaller than those occuring on the exterior of the window. It is easier for the strip 28 to seal against these relatively small pressure changes so as to exclude draughts, than it would be if a single sealing strip were located in the area of the gap 32.

The cross bar of the T shape of the extrusion 14 of the casement frame 12 provides an abutment surface 34 which has a longitudinal groove 36 receiving a sealing strip 38, of the same form and in exactly the same manner as the groove 26 receives the sealing strip 28. The exterior surface of a proprietory double glazing system 40 bears against the strip 38, and is held in place by a hollow extruded p.v.c. clip 42 which bears against the inside of the glazing system 40 via a soft p.v.c.

sealing strip 44. The clip 42 clips over longitudinal extruded lugs 46 on the extrusion of the frame 1 2.

The clip 42 is a snap fit on these lugs 46. In installing the glazing system 40, the sealing strip 38 is first inserted in the groove 36 and secured there with solvent adhesive. Then the glazing system 40 is offered up towards the abutment surface 34 sealing strip 38, and is held loosely in position by clipping the clip 42 onto the lugs 46.

Then the sealing strip 44 is pushed into place, and the arrangement is so dimensioned that this requires some force, so that there is no danger of the glazing system 40 accidentally coming adrift.

The sealing strip 44 includes a longitudinal groove which mates with a small flange 48 on the clip 42, so that the sealing strip 44 is a snap fit when it is placed in position.

The extrusion 14 of the frame 1 Oa is also provided with similar lugs 46. Although these are not used in the arrangement shown in Fig. 2, they enable exactly the same extrusion to be used for the fixed frame 1 Ob seen on the right-hand side in Fig. 1, as seen in Fig. 3. The frame 1 Ob is installed - the opposite way round to the frame 1 Oa, i.e. with the abutment surface 22 facing inwardly instead of outwardly. The sealing strip 28 (not shown in the diagrammatic view of Fig. 3) in the groove 26 then abuts the glazing system 40, and the glazing system 40 is held by a clip 42 and sealing strip 44 in exactly the same way as in Fig. 2, except that the clip 42 is now clipping onto the lugs 46 of the frame 1 Ob instead of the frame- 1 2.

In Fig. 2, there are also seen two generally square cross-section extruded members 16 of the buckframe, fitting the frame 1 Oa into an aperture in the wall 56 of a building. The buckframe members 16 have laterally projecting lugs 50, 51 which mate with a snap fit with corresponding lugs 52, 53 on the frame 1 Oa or 1 Ob. The buckframe 16 is then interlocked mechanically with the frame 10, but to ensure that it is secure it has mating faces 54 between the lugs 50, 52 to which a solvent adhesive is applied to ensure that the frame member 14 of the frame 1 Oa or 1 Ob and the buckframe 16 fuse together securely and to prevent the ingress of water or weather.Just next to the abutting faces 54, between the lugs 52 and 53, the frame member 14 has a channel 59, while the buck member 16 has a longitudinal flange 60 which fits down the sign of this channel 59, thus improving the mechanical interlock between the lugs 50, 52. The buckframe 16 is secured in an aperture in a wall 56 in any conventional manner. The buckframe 16 is not filled with foamed material 58, and thus it has a degree of resilience and can give if the structure the building should shift slightly, before any damage could occur to the frames 1 0a, 1 Ob or 12.

It also spaces the frames from the wall 56 so that the casement frame 12 can swing open about the hinge axis 24.

As seen in Fig. 3, at the joint between the frames 1 Oa and 1 Ob the surfaces 54 of two adjacent frame members 1 4 of the two frames 1 0a, 1 Ob abut and are adhered together with solvent based adhesive, again to ensure there can be no- ingress of moisture. The channels 59 of the adjacent frame members also mate with each other to form a larger channel in which fits, at both the inside and the outside of the window, a U-section coupling strip 62. The strips 62 are made of relatively rigid p.v.c. and are resilient so as to bear against the lugs 52 at the very exterior and interior of the joint between the two frame members 1 0a, 1 Ob, being provided with two longitudinal grooves which mate with the lugs 52.

They thus serve to locate and couple the frame members 14 of the two frames 1 Oa, 1 Ob together, and provide a degree of weatherproofing. Between the two sets of mating faces 54, a cavity 64 is formed by mating channels 66, one in each frame member 14. In this cavity 64, there is a foam strip 68, which has a self-adhesive coating so as to adhere to one frame member 14. This foam strip is of polyurethane and is impregnated with a water repellent to provide further security against the ingress of moisture.

Fig. 4 shows how the various frame members are mitred together at the corners. This applies both to the fixed frames 1 ova, Ob and the casement frame 12. The frame members are cut to mate at 45 0. An L-shaped corner piece 70 is injection moulded into a rectangular cross-section tubular form. The foam filling 58 at the exposed ends of the frame members 14 is cut away by a specially mounted router, to give a rectangular recess 72 which mates snugly with one limb of the L-shaped member 70. The recess 72 cuts slightly into the outer p.v.c. material of the member 14. It also has a central island 74 of the foam material 58 which fits snugly inside and tubular member 70.The same is done on the open end of the other member 14 (though this is not seen in Fig. 4). The two limbs of the L-shaped member 70 are then slotted into the recesses 72 formed for them in each frame member, after being coated with a solvent based adhesive. This provides a joint between the frame members 14 which is both mechanically secure and will not admit the weather, to give frames which are effectively single units. The machining is desirable because it is difficult or impossible to produce an accurate enough fit by moulding or extruding.

As seen in Fig. 5, instead of buckframe members 16 more conventional jamb members 1 8, 20 may be provided surrounding the frames.

These have longitudinal parallel inwardly projecting portions 76 towards the front and rear which fit into the channels 59 of the frame members 14 to provide a mechanical interlock.

The joint can then be made secure with adhesive, as before. Fig. 5 shows such jamb members at top and bottom of the frame 10, and similar members can be provided at the sides.

As seen in Fig. 6, it is not necessary for the two jambs 18, 20 to be identical, and in Fig. 6 there is seen a sill member 20' in place of the jamb member 20, the sill member projecting forwardly to provide a conventional sill.

The members 18, 20, 20' seen in Figs. 5 and 6 may be made from hardwood or from rigid extruded foam material.

Claims (15)

1. A window frame having a hinged movable light and a fixed light, the fixed light comprising glazing received against an abutment surface of a first fixed frame member, the abutment surface being generally parallel to the plane of the frame, the movable light comprising a movable frame member which when hinged into the closed position is received against the abutment surface of a second fixed frame member which has substantially the same cross-section as the first fixed frame member.

2. A window frame according to claim 1 wherein the first and second fixed frame members are disposed in opposite orientations in which their respective abutment surfaces face one inwardly of the frame and the other outwardly of the frame.

3. A window frame according to claim 1 or claim 2 wherein the abutment surfaces are provided with a resilient sealing strip to seat against the glazing or the movable frame member respectively.

4. A window frame according to any one of the preceding claims wherein the fixed light has a clip attached to the first fixed frame member to hold the glazing against the abutment surface thereof.

5. A window frame according to claim 4 wherein the first fixed frame member has a formation which receives the clip with a snap fit.

6. A window frame according to any one of the preceding claims wherein the movable frame member also has an abutment surface for receiving glazing, and glazing is held thereagainst by a clip attached to the movable frame member.

7. A window frame according to claim 6 together with claim 4 wherein the clip on the movable light and the clip to the fixed light are of substantially the same cross-section.

8. A window frame according to any one of the preceding claims wherein each light comprises four said first or second frame members joined together into a rectangular form.

9. A window frame according to any one of the preceding claims wherein the first and second frame members are formed as extrusions.

10. A window frame according to any one of the preceding claims wherein the first and second frame members are of plastics material.

11. A window frame according to claim 10 wherein the first and second frame members are hollow and are filled with a foamed plastics material.

12. A window frame according to any one of the preceding claims wherein the fixed and movable lights are joined by butt-jointing a said first and a said second frame member together, sealing means being provided to prevent ingress of moisture between said frame members.

1 3. A window frame substantially as described herein with reference to the accompanying drawings.

14. A method of making a frame for a window or the like in buildings, comprising taking an elongate hollow plastics frame member, placing it in a jig which supports the plastics material of the member against internal pressure therein, and filling it with a foamed plastics material.

15. A window or like frame comprising a main frame having at an outer edge thereof for juxtaposition with a wall in which the frame is to be mounted, a subsidiary frame member which is more resilient than the main frame.