GB2275957A - Glazing bead security clip - Google Patents

Abstract

A window assembly comprises a rectangular frame formed from four elongate profiled frame elements 10 connected together at the corners of the frame, each frame element being shaped to provide a rebate to receive a respective side edge of a rectangular glazing unit 13. Glazing beads 15 are mounted along the frame elements, after location of the glazing unit in the rebate, to engage the edges of the glazing unit so as to retain it within the rebate, each glazing bead having a longitudinal flange 16 which is received and retained within an undercut longitudinal channel 17 in the respective frame element. Previously located within each channel 17 is a resiliently deformable security clip 21 which is deformed, as the flange 16 on the glazing bead is introduced into the channel, so as to snap into engagement with the flange and oppose its subsequent withdrawal from the channel. <IMAGE>

Description

"Improvements in or relating to window assemblies" The invention relates to window assemblies of the kind comprising a rectangular frame formed from four elongate profiled frame elements connected together at the corners of the frame, each frame element being shaped to provide a rebate to receive a marginal portion of a respective side of a rectangular glazing unit, and elongate glazing beads for mounting along the frame elements, after location of the glazing unit in the rebate, to engage the marginal portions of the glazing unit so as to retain it within the rebate, each glazing bead having a longitudinal flange which, in use, is received and retained within an undercut longitudinal channel in the respective frame element.

To locate the glazing unit in the frame, it is placed within the rebate, with the glazing beads removed, and the glazing beads are then secured in position overlapping the peripheral edges of the glazing unit. The glazing beads are normally comparatively rigid, for example in the form of plastics extrusions, but have mounted thereon resiliently flexible sealing strips of rubber or soft plastics which engage the surface of the glazing unit. Assembly of the unit within the frame is then normally completed by wedging a further flexible sealing strip between the rebate and the opposite surface of the glazing unit, this serving to press the glazing unit firmly against the gasket on the removable glazing bead.

It is usual for the removable glazing beads to be provided on the side of the window which faces outwardly when the window is in position in the outer wall of the building. This simplifies the form of the profiled frame elements and also allows easier installation of the windows on site. It may also improve the weatherproofing performance of the window.

However, such externally glazed arrangements have the disadvantage that it may be possible for an intruder to force entry to the building by prising the removable glazing beads from the frame and removing the glazing unit.

To provide some security therefore, the flange on the removable glazing bead is normally hook-shaped so that the bead can only be removed by tilting it towards the glazing unit as the flange is withdrawn from the undercut channel in the frame element. Since the sealing strip on the hook bead is normally firmly in engagement with the outer surface of the glazing unit, the required tilting moving of the hook bead can only be achieved by first removing the resilient wedge sealing strip from the inner side of the window. This permits the glazing unit to be displaced inwardly thereby permitting tilting and removal of the glazing bead.

However, in some cases it may be possible for an intruder to obtain sufficient freedom of movement of the hook bead, in order to detach it, by first stripping away the resilient sealing strip which is attached to the hook bead.

The present invention therefore sets out to provide a security arrangement, for use in a window assembly of the kind first referred to, which makes it more difficult for an intruder to remove the glazing bead, even if there is sufficient room to tilt the bead in a manner which would normally be sufficient to permit its removal.

According to the invention there is provided a window assembly comprising a rectangular frame formed from four elongate profiled frame elements connected together at the corners of the frame, each frame element being shaped to provide a rebate to receive a marginal portion of a respective side of a rectangular glazing unit, and elongate glazing beads for mounting along the frame elements, after location of the glazing unit in the rebate, to engage the marginal portions of the glazing unit so as to retain it within the rebate, each glazing bead having a longitudinal flange which, in use, is received and retained within an undercut longitudinal channel in the respective frame element, there being located within the channel at least one resiliently deformable security clip which is shaped to be deformed, as the flange on the glazing bead is introduced into the channel, in a manner to tend to oppose subsequent withdrawal of the flange from the channel.

Thus, the security clips are located in the undercut channels in the frame elements before the glazing beads are applied, and once the glazing beads are fitted in position, the security clips engage the flanges on the glazing beads, within the channels, to prevent their being withdrawn from the channels. The amount of force necessary to strip the glazing beads from the window is then substantially increased since it must seriously damage the structure of the glazing beads, security clips and/or frame elements.

The flange on each glazing bead may be formed with a projecting part which is urged by the security clip into engagement with an undercut portion of the channel, whereby engagement of the projecting part in the undercut portion opposes subsequent withdrawal of the flange from the channel.

Alternatively or additionally, the security clip may have a retaining portion which is shaped to deform resiliently from an initial position to permit the flange to enter the channel, the flange being shaped to permit the retaining portion to return at least partly towards its initial position when the flange is fully entered into the channel, said retaining portion then overlying a part of the flange to oppose withdrawal of the flange from the channel.

For example, the flange may be formed with a projecting lip which snaps past the resilient retaining portion of the security clip. The lip may project in the opposite direction from the aforementioned projecting part of the flange which enters the undercut portion of the channel. Alternatively, the flange may be formed with a recess into which the retaining portion of the security clip snaps as the flange is entered into the channel.

In all the above arrangements the security clip preferably remains resiliently stressed into engagement with the flange when the flange is fully entered in the channel so as to oppose any movement of the flange within the channel.

In one embodiment of the invention the security clip comprises a base portion adapted to engage the bottom wall of the channel, a side portion adapted to engage one side wall of the channel, and a retaining portion, for engagement by the flange, which is resiliently displaceable with respect to the base portion and side portion. Preferably the retaining portion of the security clip extends into the channel from the side portion of the clip. For example, the clip may comprise a unitary device in which the side portion comprises an elongate strip and the base portion and retaining portions comprise further elongate strips, integral with the side strip, and each extending at an angle from a respective side edge of the side strip.

The base strip may extend at substantially a right angle to the side strip, at least when inserted in the channel, and the retaining strip may extend towards the base strip at an angle of less than a right angle to the side strip. The three portions of the security clip may be bent from a single elongate strip of resilient metal, such as stainless steel, but the invention also includes arrangements where the security clip is extruded or injection moulded from suitable resilient plastics material.

The retaining portion of the security clip may be formed with teeth or other projections adapted to bite into the material of the flange when the flange is fully entered into the channel.

The invention includes within its scope a set of parts for constructing a window assembly of any of the kinds referred to above and comprising four elongate profile frame elements, or one or more lengths of elongate profile frame material from which such elements may be cut, four elongate glazing beads, or one or more lengths of elongate beading material from which such glazing beads may be cut, and a plurality of security clips. The set of parts may also, optionally, include a rectangular glazing unit, such as a double-glazing panel.

The invention also includes within its scope a security clip having any of the characteristics referred to above in relation to such clip.

The following is a more detailed description of embodiments of the invention, reference being made to the accompanying drawings in which: Figure 1 is a cross-section through part of a typical window assembly of the kind to which the invention is applicable, Figure 2 is an enlarged view of part of the assembly showing the use of a security clip in accordance with the invention, Figure 3 is a section through the security clip before insertion in the window assembly, Figure 4 is an isometric view of the security clip, Figures 5 and 6 are similar views to Figure 2 showing alternative arrangements in accordance with the invention, and Figure 7 is an isometric view of a modified form of security clip.

Referring to Figure 1, there is shown a crosssection of part of an elongate frame element 10 used in a window assembly. Each frame element 10 may be extruded from plastics or aluminium and four such elements are secured together to form a rectangular frame. The precise shape and construction of the elements, and the manner in which they are connected together, do not form a part of the present invention and will not therefore be described in detail.

Each frame element 10 has an upstanding inner wall part 11 which provides a rebate 12 to receive the marginal portion of one side of a glazing unit 13, such as a double glazed panel. A resilient flexible sealing strip 14 is disposed between the wall part 11 of the frame element and the inner surface of the glazing unit 13.

The glazing unit 13 is held in the rebate by glazing beads 15, one glazing bead being mounted along each frame element 10. The glazing beads 15 are of the kind known as "hook beads" being formed with a hook-like flange 16 which is received within an undercut channel 17 in the frame element 10. By an "undercut" channel is meant a channel in which one or each side wall of the channel is formed with a longitudinal recess.

In order to mount the glazing unit 13 in the frame, the glazing unit is first introduced into the rebate 12 so as to rest against the rear walls 11 of the frame elements 10, the sealing strips 14 at this stage being omitted. The glazing beads 15, with resiliently flexible sealing strips 18 mounted thereon, are then mounted on the frame elements 10 so as to engage the front peripheral surfaces of the glazing unit 13. To introduce the flanges 16 of the glazing beads 15 into the channel 17, the glazing beads 15 must first be tilted towards the glazing unit 13 and then swung outwardly and downwardly to enter the flanges 16 into the channels 17. There is sufficient room to effect this operation since the glazing unit 13 will be hard against the inner wall 11 of the frame elements 10.

Once the glazing beads 15 are in the position shown in Figure 1, the sealing strips 14 are introduced between the inner wall portions 11 and the glazing unit 13 to urge the glazing unit outwardly against the sealing strips 18.

In this position, the glazing beads 15 nominally cannot be removed since there is insufficient space to tilt them towards the glazing unit 13 to effect removal of the flanges 16 from the channel 17. However, in practice the glazing beads 15 might be removed by a potential intruder by stripping the sealing strips 18 from the glazing beads and then prising the beads upwardly by means of a screwdriver, chisel or similar implement. The present invention provides security clips to make such forceful removal of the glazing beads more difficult or impossible.

In the embodiment shown in Figure 2 the depending hook-like flange 16 on the glazing bead 15 is formed on its extremity with an inwardly projecting foot portion 19 and an outwardly projecting lip 20. Before each glazing bead 15 is mounted on its associated frame elements 10 one or more security clips 21 are introduced into the undercut channel 17 of each frame element. The security clip may only be an inch or two in length and it may be sufficient to mount only a single security clip in each frame element.

However, for added security, or in larger windows, two or more security clips may be spaced apart along each frame element.

Referring to Figures 2, 3 and 4, each security clip 21 is bent from a flat strip of resilient metal, such as 0.2 mm stainless spring steel and comprises a base strip 22, a side strip 23, and a retaining strip 24. The base strip 22 extends generally at right angles to the side strip 23 whereas the retaining strip 24 is inclined at less than a right angle, for example, 50 , to the side strip 23 so as to point towards the base strip 22.

The dimensions of the side strip 23 and base strip 22 are preferably such that when the security strip is introduced into the channel 17, as shown in Figure 2, the side strip 23 is wedged into an undercut recess 25 in the front wall of the channel while the extremity of the base strip 22 engages within an undercut recess 26 in the inner wall of the channel. To facilitate this wedging action the angle between the base strip and side strip 23 may initially be slightly greater than a right angle, as shown in Figure 3. The dimensions within the channel 17 thus force the two strips 22 and 23 into right angled relation, as shown in Figure 2, where they are held by the strips bearing resiliently against the walls of the channel.

The wedging of the security clip 21 in the channel 17 also serves to prevent displacement of the clip along the channel after it has been fitted. This is particularly important in the case where the clip is fitted to vertical window frame elements, since otherwise the clip or clips would be liable to slide downwardly to the bottom of the frame element.

As the flange 16 of the glazing bead is subsequently introduced into the channel 17 the lip 20 on the flange bears on the retaining strip 24 of the security clip and forces it towards the side strip 23.

As the flange 16 is entered fully into the channel, the retaining strip 24 snaps back above the lip 20 and into engagement with the outer surface of the flange 16.

For clarity in Figure 2 the retaining strip 24 is shown spaced from the flange 16 and the foot 19 of the flange is shown spaced from the bottom wall of the recess 26. In practice, however, the shape and dimensions of the security clip 21 are such that, when the flange 16 is fully entered into the channel 17, the retaining strip 24 resiliently engages the outer surface of the flange 16 and forces the projecting foot portion 19 firmly into the recess 26.

When the glazing bead 15 is in position, the security clip 21 prevents ready withdrawal of the flange 16 from the channel 17. This is partly because the end of the strip 24 overlies the lip 20, preventing its withdrawal from the channel, and partly because the resilient strip 24 urges the foot portion 19 of the flange into the recess 26.

If an intruder tries to prise the glazing bead 15 away from the frame element 10, for example by introducing a screwdriver or chisel into the gap 27 between the two parts, the retaining strip 24 simply becomes more and more tightly wedged between the lip 20 on the flange 16 and the upper surface of the recess 25, thus preventing removal of the glazing bead.

Figures 5-7 show alternative arrangements and parts corresponding to those of Figures 1-4 are given the same reference numerals.

In the arrangement of Figure 5 the flange 16 on the glazing bead 15 is formed along its outer surface with a longitudinal recess or groove 28 into which the extremity of the resilient retaining strip 24 snaps as the flange is introduced into the channel 17. Again, due to the engagement of the strip 24 within the recess 28, any attempt to prise the glazing bead 15 from the frame element 10 will result in the strip 24 being wedged more and more tightly between the flange and the recess 25 in the frame element. Again, although not shown in Figure 5, the dimensions are preferably such that the resilience of the security clip wedges it firmly in the channel and forces the projecting foot portion 19 of the flange firmly into the recess 26.

In the alternative arrangement shown in Figure 6 the flange 16 on the glazing bead 15 is not provided with any formation, such as a lip or recess, which is positively engaged by the retaining strip 24 on the security clip, but the retaining effect of the clip is provided solely by its urging the projecting foot portion 19 of the flange 16 into the undercut recess 26 in the channel 17.

In order to enhance the retaining effect of the security clip in arrangements of the kind shown in Figures 2 and 5, the security clip 21 may be of the modified kind shown in Figure 7 where the free edge extremity of the retaining strip 24 is toothed, as indicated at 29, so as positively to bite into the material of the flange 16 on the glazing strip.

Although, as previously described, the security clip 21 is preferably formed from stainless spring steel, it may also be made from other materials.

For example, engineering plastics could be used to produce clips by injection moulding or extrusion.

Although a one-piece security clip is preferred, the invention does not exclude arrangements in which the clip is formed from two or more connected elements, nor arrangements in which the operative elements of the clip are differently shaped and located from the arrangement shown in the drawings.

Claims (16)

1. A window assembly comprising a rectangular frame formed from four elongate profiled frame elements connected together at the corners of the frame, each frame element being shaped to provide a rebate to receive a marginal portion of a respective side of a rectangular glazing unit, and elongate glazing beads for mounting along the frame elements, after location of the glazing unit in the rebate, to engage the marginal portions of the glazing unit so as to retain it within the rebate, each glazing bead having a longitudinal flange which, in use, is received and retained within an undercut longitudinal channel in the respective frame element, there being located within the channel at least one resiliently deformable security clip which is shaped to be deformed, as the flange on the glazing bead is introduced into the channel, in a manner to tend to oppose subsequent withdrawal of the flange from the channel.

2. A window assembly according to Claim 1, wherein the flange on each glazing bead is formed with a projecting part which is urged by the security clip into engagement with an undercut portion of the channel, whereby engagement of the projecting part in the undercut portion opposes subsequent withdrawal of the flange from the channel.

3. A window assembly according to Claim 1 or Claim 2, wherein the security clip has a retaining portion which is shaped to deform resiliently from an initial position to permit the flange to enter the channel, the flange being shaped to permit the retaining portion to return at least partly towards its initial position when the flange is fully entered into the channel, said retaining portion then overlying a part of the flange to oppose withdrawal of the flange from the channel.

4. A window assembly according to Claim 3, wherein the flange is formed with a projecting lip which snaps past the resilient retaining portion of the security clip.

5. A window assembly according to Claim 4, wherein the lip projects in the opposite direction from the aforementioned projecting part of the flange which enters the undercut portion of the channel.

6. A window assembly according to Claim 3, wherein the flange is formed with a recess into which the retaining portion of the security clip snaps as the flange is entered into the channel.

7. A window assembly according to any of Claims 1 to 6, wherein the security clip remains resiliently stressed into engagement with the flange when the flange is fully entered in the channel so as to oppose any movement of the flange within the channel.

8. A window assembly according to any of Claims 1 to 7, wherein the security clip comprises a base portion adapted to engage the bottom wall of the channel, a side portion adapted to engage one side wall of the channel, and a retaining portion, for engagement by the flange, which is resiliently displaceable with respect to the base portion and side portion.

9. A window assembly according to Claim 8, wherein the retaining portion of the security clip extends into the channel from the side portion of the clip.

10. A window assembly according to Claim 9, wherein the clip comprises a unitary device in which the side portion comprises an elongate strip and the base portion and retaining portions comprise further elongate strips, integral with the side strip, and each extending at an angle from a respective side edge of the side strip.

11. A window assembly according to Claim 10, wherein the base strip of the security clip extends at substantially a right angle to the side strip, at least when inserted in the channel, and the retaining strip extends towards the base strip at an angle of less than a right angle to the side strip.

12. A window assembly according to Claim 10 or Claim 11, wherein the three portions of the security clip are bent from a single elongate strip of resilient metal.

13. A window assembly according to any of Claims 1 to 12, wherein the retaining portion of the security clip is formed with teeth or other projections adapted to bite into the material of the flange when the flange is fully entered into the channel.

14. A set of parts for constructing a window assembly according to any of the preceding claims, and comprising four elongate profile frame elements, or one or more lengths of elongate profile frame material from which such elements may be cut, four elongate glazing beads, or one or more lengths of elongate beading material from which such glazing beads may be cut, and a plurality of said security clips.

15. A set of parts according to Claim 14 and further including a rectangular glazing unit.

16. A window assembly substantially as hereinbefore described with reference to the accompanying drawings.