GB2197671A - Universal cavity closure system - Google Patents

Abstract

A modular cavity closure comprises one or more elongate closure elements 6, 7, 8, of generally square, rectangular, "L" or "U" cross-section and having longitudinal channels 9, formed on at least one face, and a flange element 13, resiliently engaging in a channel and having a flange extending away from the closure element and parallel to one face thereof. Closure elements may be joined by joining strips 11 of "bow-tie" cross-section engaging resiliently in undercut channels in the respective closure elements or may be joined by a rib formed on one closure element being received in a channel in the other (see Figure 8 not shown). <IMAGE>

Description

"UNIVERSAL CAVITY CLOSURE SYSTEM The present invention relates to cavity closure elements, and particularly concerns a modular system allowing cavity closures of differing span to be assembled from a small number of basic components.

In the construction of buildings, the use of a cavity wall having outer and inner leaves separated by an insulating cavity is well known, and the problem of providing a closure for the cavity to surround window and door openings is one to which many solutions have been proposed.

In general, previous attempts to provide an effective cavity closure have been directed to providing flanged extruded sections either from metal or rigid plastics materials and these solutions have their own disadvantages.

The metal cavity closures of the prior art are generally complicated sections, and in order to provide thermal insulation between the leaves of the wall it usually requires the addition of insulating material as a finishing operation. Similarly, the plastics closures of the prior art are generally extruded box sections which are cut to standard lengths and then filled with rigid insulating foam, to enhance both their rigidity and insulating effectiveness.

Both these methods are costly, as they involve a two step manufacturing process, and provide cavity closures which can only be used in cavities having a predetermined span.

The present invention seeks to provide a modular system of cavity closure elements in which the closure elements are formed and foam-filled in a single operation, and may be oriented or assembled to provide effective closures for a plurality of different cavity spans using a small number of closure elements.

Another object of the present invention is to provide a plurality of flanged cavity closures, suitable for use in cavities of different span, by orienting or assembling cavity closure elements and attaching thereto resilient flange elements by snap-engagement of the flange elements in grooves formed in the closure elements.

According to the present invention, a cavity closure comprises one or more elongate elements of rectangular cross-sectional shape, each element being formed with a longitudinal channel on at least one face, and at least one elongate flange element resiliently engaging within the channel to extend in a plane parallel to a face of the closure element.

Preferably, the channel or channels formed in the closure element are trapezoidal in cross-section to afford an undercut to assist in retaining a flange element or the like.

By "rectangular cross-sectional shape" it is intended to include not only simple rectangles such as squares and other quadrilaterals, but also symmetrical and asymmetrical "L" shapes and "U" shapes provided that their external faces lie in orthogonal planes.

Various embodiments of the invention will now be described with reference to the accompanying drawings, in which: Figure 1 shows a horizontal section through a cavity wall at a side of a window opening; Figure 2 is a view similar to Figure 1, the cavity being of a different span; Figure 3 shows a cross-section of a plurality of assembled cavity closure elements, illustrating various means of retaining elements assembled and of attaching flanges; Figure 4 shows a second cavity closure element in a sectional view similar to Figure 1; Figures 5 and 6 show various flange elements which may be attached to the closure element, in cross-section; and Figure 7 shows, in a view similar to Figure 1, an "L" shaped closure element with a flexible flange attached.

Referring now to Figure 1, a cavity wall is shown comprising inner leaf 1, outer leaf 2 and a cavity 3 therebetween. At the edge of the window opening, the cavity span is reduced by the projecting portion 4 of inner leaf 1.

The cavity 3 is closed by a cavity closure 5 comprising three closure elements 6, 7 and 8. The closure elements 6, 7, 8 are square in cross-section and have an undercut channel 9 extending longitudinally at the centreline of each face. The closure elements are preferably formed of rigid plastics material and are foam-filled.

Most preferably, the closure elements are formed from a material which during the forming operation provides an impervious outer skin and a core of dense foam. Such a material is known as "Celuform", and may be either extruded as a continuous length or injection moulded.

The closure elements 6, 7, 8 are arranged in a side-by-side array, and are joined together by resilient link strips 11 which are of a cross-section comprising two isosceles trapezoidal portions joined at their shorter parallel sides to form a "bow tie" shape.

The resilient link strips 11 are push fitted into the grooves 9 and by their resilience retain the closure elements together.

To fix the closure elements to a window frame 12 or the like, a flange element 13 is provided. The flange element shown in Figure 1 is an angle section, having a trapezoidal rib 14 projecting from one of its faces. The rib 14 is snap-engageable in one of the grooves 9 of the closure element 8, and the flange element 13 is fixed to the window frame 12 by nails 15 or screws or the like. A coat of finishing plaster 16 on the inner leaf 1 of the wall completely covers the cavity closure and flange element.

In the arrangement shown in Figure 2, two closure elements 16, 18 similar to elements 6, 7, 8 are used side-by-side joined by a link strip 21. A flange element 23 is attached to the closure element 18 by snap-engagement of two lip portions 24 with the undercut faces of two grooves 9 of the closure element 18. The flange element 23 is fixed to window frame 22 by means of nails or screws 25 as before.

In both the arrangements shown, the flange element not only anchors the cavity closure to the window frame, thus keeping it in place, but the flange element also serves to form a seal between the window frame and the cavity closure, preventing the ingress of moisture and the loss of heat to the outside.

Figure 3 shows an array of four cavity closure elements 26, 27, 28, 29, to illustrate various alternative link devices and flange elements. Closure elements 26 and 27 are joined by a "bow tie" link strip 31, as previously described.

Closure elements 27 and 29 are joined by a flat link strip 32, which is a planar elongate strip having inturned lips 34 along its side edges. The link strip 32 is sufficiently resilient for the lips 34 to be snap-engaged into adjacent grooves of the closure elements to secure the elements together.

Flange element 35 is a planar flange element comprising a flat strip having an upstanding trapezoidal rib 36 extending along one edge. The resilience of the material of the flange element permits snap-engagement of the rib 36 into a groove of a closure element.

A combined flange and link element is shown at 37, the combined element comprising two parallel portions 38 having inwardly directed lips 39 the parallel portions 38 joined by a web 40. A flange portion 37a extends away from the web 40 at right angles thereto. Again the resilience of the material allows snap-engagement of the lips 39 into the grooves of the closure elements 26, 28.

Figure 4 shows, in horizontal section, a cavity closure element 40 of rectangular cross-section placed in a cavity 41 between inner and outer leaves 42, 43 of a cavity wall. The rectangular shape of the closure element allows single grooves 45 to be formed centrally on its shorter faces, and pairs of grooves 46 to extend along its longer faces, trisecting them. This arrangement ensures that the ribs 47 of a flange element 44 may be snap-engaged into the two grooves adjacent any corner of the closure element 40, and the flange portion 44a may extend either in the plane of a longer face or in the plane of a shorter face, as desired.Thus, a cavity closure element is provided which may be used in the orientation shown to close a cavity of a span A, corresponding to the longer dimension of the closure element, or the closure element may be arranged at 900 to the orientation shown, to close a cavity of span B, such as is shown in Figure 1. In the latter case, flange element 44 will engage the grooves 45 and 46 adjacent the corner of the closure element marked "C" in Figure 4.

Figures 5 and 6 illustrate various flange elements which may be provided to co-operate with the grooved closure elements. It will be clear that while they are shown fitted to a closure element of rectangular cross-section, the flange elements are equally co-operable with the square-section closure elements described previously. Similarly the link elements described above may be used to secure together rectangular elements to provide cavity closures for differing cavity spans. The flange elements shown in Figures 5 and 6 are of material sufficiently resilient to permit their snap-engagement with the grooves of the closure elements. Clearly those flange elements which engage in grooves formed on orthogonal or opposing faces of the closure element do not require the grooves to be undercut, and simple channel section grooves may be used.

Figure 7 shows a further alternative form of cavity closure element, of generally "L" shaped cross-section. The closure element 50 has two arms 51, 52 of unequal length but uniform thickness T, and may be used singly to close a cavity of span S1 in the configuration shown in Figure 7, or may be rotated through 900 to close a cavity of a greater span S2 (see Figure 9). As a further alternative, two closure elements 50 may be assembled together to form a cavity closure suitable for use in a cavity of span S3 (Figure 8).

A flange element 53 is snap-fitted into a groove in the closure element 50 by a trapezoidal rib 54, and the flange element is fixed to a door or window frame 55 as described above. In the embodiment shown, the flange element 53 is sufficiently flexible to be simply bent to lie on the inside face of the window frame 55, where it is held in place by nails 57. The resilience of the material will hold the flange element tightly against the window frame, to form an effective seal.

While all the previous embodiments of the closure element have been of rectangular cross-section, and have been formed only with longitudinal grooves, the "L" shaped embodiment includes a single longitudinal rib 58 formed on the face of its shorter arm 52 adjacent the longer arm 51. The position and dimensions of this rib are such that when two closure elements are arranged as shown in Figure 8, the rib 58 of each element enters a groove 59 in the end face of the longer arm 53 of the "L", and is held there in an interference fit. The rib 58 may even be slightly undercut to enhance the grip. Alternatively, rib 58 may be replaced by a groove, and "bow tie" or other link strips may be used to join the elements.

There is thus provided a modular system for providing cavity closure elements suitable for a plurality of cavity spans using one or more identical closure elements. Preferably the cavity closure element provides two distinct cavity spanning dimensions depending on its orientation and may be joined to one other identical closure element to provide a plurality of possible span dimensions. For example, two closure elements as shown in Figure 9 may be joined to provide span dimensions of 2 x S1, 2 x S2, 53 and S1 + S2.

The provision of grooves on the faces of the closure elements allows flange elements of many different configurations to be attached thereto in various relative positions : all of the flange elements shown may be attached to any of the closure elements shown in at least two different positions.

The invention therefore provides a modular cavity closure system having few components and capable of providing a multiplicity of different cavity closures for differing applications.

Claims (13)

1. A cavity closure comprising an elongate closure element having two pairs of parallel faces, the faces of each pair being arranged in planes perpendicular to the faces of the other pair, and one face of the closure element being formed with a longitudinal channel, and a flange element engaging in the channel and having a flange extending so as to be substantially parallel to a face of the closure element.

2. A cavity closure according to Claim 1, including two or more closure elements joined together.

3. A cavity closure according to Claim 2, wherein the closure elements are joined by a resilient strip which engages in respective channels of adjacent closure elements.

4. A cavity closure according to Claim 2, wherein the closure elements are joined by means of a longitudinal rib of a first closure element engaging in a corresponding channel of a second closure element.

5. A cavity closure according to any preceding Claim, wherein the, or each, channel is undercut so as to have its greater width at a distance below the surface of the closure element.

6. A cavity closure according to Claim 5, wherein the flange element includes a resilient longitudinal rib whose transverse section corresponds to that of a channel, and which may be resiliently deformed so as to enter the channel.

7. A cavity closure according to Claim 1, wherein the flange element includes resilient lips to engage channels on adjacent faces of the closure element.

8. A cavity closure according to Claim 5, wherein the flange element comprises resilient lips to engage two channels formed in a face of the closure element.

9. A cavity closure according to any preceding Claim wherein the flange of the flange t.lr.1#r--.flf. extends 50 as to be substantially ti coplanar with a face of the closure element.

10. A cavity closure according to any preceding Claim wherein the closure element is an extruded plastics section.

11. A cavity closure according to Claim 10, wherein the closure element has an impervious skin and a foamed core.

12. A cavity closure according to any preceding Claim wherein the flange element is formed of metal or extruded plastics material.

13. A cavity closure substantially as herein described with reference to figures 1 to 3, figures 4 and 5, figure 6, or figures 7 to 9 of the accompanying drawings.