GB2348603A

GB2348603A - Fire barrier or cover for electrical fittings

Info

Publication number: GB2348603A
Application number: GB9906503A
Authority: GB
Inventors: Uri Friedlander
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-03-23
Filing date: 1999-03-23
Publication date: 2000-10-11
Anticipated expiration: 2019-03-23
Also published as: GB2348603B; GB9906503D0

Abstract

A fine barrier 1 for use with an electrical fitting recessed into a supporting structure is constructed of fire resistant fabric and is generally in a conical, pyramidal or domed form as a hood to overlie the fitting. The barrier is foldable to be inserted through an aperture 6 in the recessed structure whereby when the fabric is inserted through the aperture it may be readily manipulated through the aperture or is resiliently biased to unfold and adopt a form to be self supporting and thereby stand protectively over the fitting. The fitting is typically in a ceiling.

Description

FIRE BARRIER FOR ELECTRICAL FITTINGS Field of the Invention The present invention relates to fire barries for recessed electrical fittings and more particularly for recessed electrical fittings such as, for example, light fittings for ceilings.

Background to the Invention Prior art fire barries for recessed electrical fittings comprising fire resistant fabric hoods or frame-supported fire resistant fabric sheets are known of from, amongst others, GB 2297609 and GB 2235710. Such barries, in the case of GB 2235710 are bulky having large metal frames and are clearly designed to be installe from above the ceiling, the ceiling being a suspende ceiling with access obtained through removal of adjacent ceiling panels of the suspende ceiling.

In the case of GB 2 297609, the fire resistant fabric hood is illustrated as a generally cylindrical structure having side walls and a top with stiffening wire to support the side walls and a disk of intumescent card secured to the top to stiffen and protect the top while providing venting and access for the power cable to the light fitting. In this latter case, the hood is intended to be rolled up or squashed to form a tube to insert through the ceiling opening but will be restricted by the size of the disc and relies upon the stiffening wire to provide support.

It is one general objective of the present invention to provide an improved fire barrier that can, for example, be inserted up through the smallest of ceiling openings without affecting the integrity of the banier and which does not rely upon having supportive wire uprights.

Summary of the Invention According to a first aspect of the pèsent invention there is provided a fire barrier for use with a recessed electrical fitting recessed into a supporting structure, which barrier is constructed in fire resistant fabric, being formed to a generally conical, pyramidal or domed form to overlie the fitting as a hood and being foldable to be inserted up through an aperture in the recessed structure for the recessed electrical fitting, whereby when the hood is inserted up through the ceiling aperture it may be readily manipulated through the aperture or resiliently biased to unfold and adopt its shape or form to be self supporting and thereby stand over the fitting.

Preferably the fire barrier hood further comprises a resilient biasing means fitted to the region of the rim of the conical, pyramidal or domed hood to bias the fabric to unfold into its conical, pyramidal or domed form.

Preferably hook or clip means are provided at the region of the rim of the conical, pyramidal or domed form to cooperatively engage a rim of an aperture in the ceiling or other surface into which the electrical fitting is recessed to hold the barrier hood laterally in place.

Suitably the barrier hood is formed in two layers of fabric, an inner layer and an outer layer stitched, glued or otherwise fastened to each other.

Suitably a void between the two layers of fabric is wholly or partially filled with beads or strands of fire resistent material such as, for example, glass fibre or metallic beads.

The inner and outer layers of fabric may be stitched or glued or otherwise fastened together to form a series of flutes, or pockets, the flutes or pockets being filled with the fire resistant material.

According to a second aspect of the present invention there is provided a fire barrier for use with a recessed electrical fitting which barrier is constructed in fire resistent fabric as a hood to overlie the fitting and wherein the hood is integrally mounted to the exterior of the ftting, whereby the hood is installed or removed from the ceiling or other recessed surface simultaneously with the fitting.

In accordance with a third aspect of the present invention there is provided a fire barrier of the first aspect of the pèsent invention in combination with a recessed electrical fitting recessed into a supporting structure, such as, for example, a ceiling.

According to a fourth aspect of the present invention there is provided a method of installation of a fire barrier of the first aspect of the invention comprising providng the fire barrier of the first aspect of the invention and folding the hood and inserting it through an aperture in a said recessed structure and manipulating it through the aperture or allowing it to be resiliently biased to unfold and adopt its shape or form to be self supporting and thereby stand protectively over the fitting.

According to a yet further aspect of the pèsent invention there is provided a method of manufacturing a fire barrier for use with a recessed electrical fitting recessed into a supporting structure, which method of manufacture comprises pressing or cutting one or more pieces of fire resistant fabric from a sheet of fire resistent fabric and assembling the one or more pieces to form a generally conical, pyramidal or domed form as a hood to overlie a said--electdcal fitting.

Brief description of the drainas Preferred embodimçnts of~the present invention will now be more particularly described, by way of example, with reference to the accompanying drawings, wherein : Figure 1 is a perspective view of a first preferred embodiment of fire barrie hood of the present invention ; Figure 2 is a perspective view illustrating installation of the fire barrier hood into a ceiling recess ; Figure 3 is a perspective view of a second embodiment of the invention ; Figure 4 is a part cut away view of the second embodiment ; Figure 5 is a perspective view of a third embodiment of the invention ; and Figures 6 and 7 are a perspective and part cutaway view respectively of an embodiment of the second aspect of the invention.

Description of the Preferred Embodiments The first embodiment of the fire barrier hood illustrated in Figure 1 comprises a cone 1 formed from a sheet of fire resistant fabric. This sheet of fire resistent fabric may, for example, be a closely woven mat of glass fibre that may be coated in a vulcanise organic polymer and that may suitably be cut to a generally circular shape from a larger sheet of glass fibre and then folded into the conical form and with the overlapping edge 2 stitched, glued or otherwise fastened in place. An example glass fibre cloth is that manufactured and sold as Firetherm 30/90 by Intumescent & Insulation Supplies Ltd of Dartford Kent.

The cone 1 preferably comprises not just a single glass fibre layer but rather a pair of layers, inner 3 and outer 4 that are stitched together at their peripheries 5 forming an inner and an outer skin with a void there between. This void may then be filled with a further fire resistent material such as, for example, metal beads or glass fibre beads or other inorganic fillers or fibres.

As can be seen in Figure 2, the fabric construction of the fire barrie hood enables it to be folded and compresse around its longitudinal axis to redue its diameter and thereby enable it to be passed up through an aperture 6 for a recessed electrical fitting such as, for example, a ceiling aperture for down lighter light fitting.

Once the barrier hood has been passed up through the aperture 6 in the ceiling it may then be unfolded to deploy its conical form. The unfolding action may be carried out by manipulating the fabric manually or it may be carried out by the biasing action of a spring 7 mounted, preferably sewn, in the circular rim 5 of the conical hood.

As a further design feature, the hood incorporates a pair of metal clips extending inwardly from the dm 5 to hook over the edges of the ceiling aperture 6 to hold the hood in place over the aperture 6, resisting lateral movement. In combination with the spring 7, these clips 8 may serve not simply as detents but also grip the circular wall of the ceiling aperture 6.

As described above, the hood preferably has a layered construction sandwiching between the innner 3 and outer 4 layers of fabric a plurality of fireresistant material beads or stands. In the second embodiment of the invention illustrated in Figures 3 and 4, the fire resistant material sandwiche within the inner 3 and outer 4 skins of the hood is suitably compartmentalised. In this illustrated embodiment the fire resistant material filling 11 is compartmentalised not only into a plurality of flutes 9 around the hood but also into a lower, in use, portion 10 of the hood.

The purpose of this is to provide a low and evenly distributed center of gravit, with the fire resistant material ballasting the hood to lie stationary in the desired configuration.

A yet further embodiment of the invention is illustrated in Figure 5 and comprises a fire banier hood having a generally domed shape rather than a conical form. In common with the conical~~form and also with pyramidal shapes, this domed form facilitates insertion of the barrier hood up through the ceiling aperture while also facilitating deployment of the hood in the required configuration so that the hood may be free standing without need for use of any rigid framework, including any wire uprights.

Referring to Figures 6 and 7, here the conical fire barder hood 1 is integrally assemble to an electrical fitting-in the illustrated example the fitting is a down-lighter 12. The rim 5 of the conical hood 1 is glued, rivette or otherwise bonded to an upstanding annular flange 13 on the rear face of the downlighter. The power cables 14 of the downlighter protrude through apertures 15 in the side of the hood 1. In this aspect of the invention although the illustrated embodiment is of a conical hood, the hood may be of any suitable shape-preferably conical, domed or pyramidal-but may be cylindrical, for example.

From the foregoing it will be appreciated that the present invention provides a number of benefits over the prier art. Although described with respect to a small number of preferred embodiments, many alternative embodiments are conceivable within the scope of the present invention.

Claims

CLAIMS 1. A fire barrier for use with a recessed electrical fitting recessed into a supporting structure which barrier is constructed in fire resistant fabric, being formed to a generally conical, pyramidal or domed form as a hood to overlie the fitting and being foldable to be inserted through an aperture in the recessed structure whereby when the fabric is inserted through the aperture it may be readily manipulated through the aperture or resiliently biased to unfold and adopt its or form to be self supporting and thereby stand protectively over the fitting.
2. A fire barrier as claimed in claim 1, wherein a resilient biasing means is fitted to the region of the rim of the conical, pyramidal or domed form of the barriez to bias the fabric to unfold to adopt its conical, pyramidal or domed form.
3. A fire barrier as claimed in claim 1 or claim 2, wherein hook means or clip means are provided at the region of the rim of the conical, pyramidal or domed form to cooperatively engage a rim of a said aperture in a said supporting structure to hold the barrier in place.
4. A fire barrier as claimed in any preceding claim, wherein the conical, pyramidal or domed fonm comprises two layers of the fire resistant fabric, an inner layer and an outer layer, stitched or glued or otherwise fastened to each other.
5. A fire barrier as claimed in claim 4, wherein a void between the two layers of fabric is wholly or partially filled with beads or strands of fire resistant material.
6. A fire barrier as claimed in claim 4 or claim 5, wherein the inner and outer layers of the barrier are stitched, glued or otherwise fastened together to form a series of pockets or flutes, said pockets or flutes being filled with the fire resistant material.
7. A fire banrier for use with a recessed electrical fitting which barrier is constructed in fire resistent fabric as a hood to overlie the fitting and wherein the hood is integrally mounted to the exterior of the fitting, whereby the hood is installe or removed from the ceiling or other recessed surface simultaneously with the fitting.
8. A fire barrier of claim 1 in combination with a recessed electrical fitting recessed into a supporting structure, such as, for example, a ceiling.
9. A method of installation of a fire barrier of claim 1 comprising providing the fire barrier of claim 1 and folding the hood and inserting it through an aperture in a said recessed structure and manipulating it through the aperture or allowing it to be resiliently biased to unfold and adopt its shape or form to be self supporting and thereby stand protectively over the fitting.
10. A method of manufacturing a fire barrier for use with a recessed electrical fitting recessed into a supporting structure, which method of manufacture comprises pressing or cutting one or more pieces of fire resistant fabric from a sheet of fire resistent fabric and assembling the one or more pieces to form a generally conical, pyramidal or domed form as a hood to overlie a said electrical fitting.