GB2471929A

GB2471929A - An intumescent electrical fitting

Info

Publication number: GB2471929A
Application number: GB1010302A
Authority: GB
Inventors: John Desmond; Richard Kemp
Original assignee: JCC Lighting Products Ltd
Current assignee: JCC Lighting Products Ltd
Priority date: 2009-07-17
Filing date: 2010-06-18
Publication date: 2011-01-19
Anticipated expiration: 2030-06-18
Also published as: GB201010302D0; GB0918151D0; GB0912464D0; GB2471929B

Abstract

An electrical fitting 1 adapted to be fitted to a panel (2, fig 2) has a tubular can 3 with first and second ends 7, 8. The can 3 receiving a lamp 9 through an opening at the first end 7. An end cap 10 is secured to cover an opening at the second end 8. The end cap 10 has one or more elongate ventilation slots 14 and is formed from an intumescent material so that the end cap 10 will inhibit the transmission of fire through the light fitting through the ventilation slots 14. Other inventions relate to electrical fittings and a lamp socket.

Description

Title: An electrical fitting, a cap for an electrical fitting, a kit of parts, a lamp socket and associated methods The present invention relates to an electrical fitting, a method of constructing an electrical fitting, a kit of parts for an electrical fitting, and a lamp socket.

More particularly, aspects of the invention relate to a light fitting including an intumescent material.

Recessed downlights are well known and have become popular in recent years. These lights are usually fitted to a ceiling of a room such that a lamp of the light is configured to emit light through a hole in the ceiling and a front face of the lamp is substantially aligned with the plane of the ceiling. The rear of the lamp extends above the ceiling into, for example, a roof-space of a building of which the room is a part. Wiring and the like for the light is hidden from view by the ceiling. The downlight may include a flange which, when the downlight is fitted to a ceiling, covers an edge of the hole in the ceiling from the view of occupants of the room.

Importantly, the hole which is required in the ceiling of a building in order to fit a downlight provides an aperture through which fire can spread between the levels of a multi-story building.

Modern building regulations require certain standards for the construction of ceilings which inhibit the spread of fire.

Accordingly, downlight fittings have been created. These typically comprise a can having a tubular main body with a cover plate at one end and an open opposing end. An electrical connection block is provided adjacent the cover plate and a flange is provided around the open end of the can. The can is inserted through the hole in the ceiling and the lamp of the downhight is fitted inside the can. A suitable lamp connector is, of ôourse, provided inside the can and in electrical communication with the electrical connection block of the downlight.

When a downlight fitting of this type is fitted to a ceiling, the can and flange of the downlight provide, with the ceiling, a substantially continuous surface which acts as a fire sheild inhibiting the spread of fire between levels of a building.

However, ventilation is required such that the heat generated by the lamp can be vented into the room and the roof-space (for example). To this end, one or more apertures are provided in the cover plate of the can of the downligh.

fitting.

A downlight fitting with one or more such apertures in the cover plate is clearly not as effective a fire shield as a downlight fitting without any apertures through he cover plate. In addition, the flange of the fitting may not abut against the ceiling to provide a perfect seal between the downlight fitting and the ceiling. Thus, fire can pass through any apertures or gaps between the flange and the ceiling -consequently, permitting the fire to spread between the levels of a building.

This problem has been realised and addressed. A significant advance was made when the use of an intumescent material in downlight fittings was introduced in GB24221 91.

Intumescent material expands (or swells) when exposed to fire. This material may be placed adjacent ventilation apertures in the downlight fitting and around an interior surface of the flange. Thus, when the downlight fitting is exposed tO fire, the intumescent material expands to substantially seal the apertures and the gaps between the flange and ceiling -thus creating a fire shield which hinders the spread of fire.

Despite this significant and important advance, the pieces of intumescent material must be carefully fitted with respect to the apertures and gaps they are intended to seal in the event of a fire. The intumescent material may also need to be secured to the downlight fitting by the use of a separate steel plate sandwiched between this plate and the cover plate of the can of the downlight fitting. Thus, a complicated manufacturing process is required.

Embodiments of the present invention seek to ameliorate some of the

problems associated with the prior art.

Accordingly, an aspect of the present invention provides an electrical fitting adapted to be fitted to a panel, comprising: a tubular can with first and second opposing ends, the tubular can being adapted to receive at least part of an electrical unit through an opening at the first end; and an end cap secured to cover an opening at the second end of the tubular can, wherein the end cap defines one or more elongate ventilation slots and is formed from an intumescent material such that the end cap inhibits the transmission of fire through the light fitting through the or each ventilation aperture.

Preferably, the end cap is substantially self-supporting and/or rigid.

Conveniently, the end cap is at least partially received by the tubular can.

Preferably, the tubular can is at least partially received by the end cap.

Conveniently, the fitting further comprises an annular cuff fitted around the end cap.

Advantageously, the intumescent material comprises a thermoplastic mixed with an intumescent powder.

Preferably, the thermoplastic is PVC, ABS, or polyethylene.

Conveniently, the light fitting further comprises a face ring or gasket attached to the first end of the tubular can to provide a thermal break between an extreme end of the light fitting and the tubular can.

Advantageously, the end cap comprises an end wall and a perimeter wall which extends from a perimeter of the end wall.

Preferably, the end cap is substantially cup shaped.

Conveniently, the end cap is attached to the tubular can by a press-fittinj arrangement.

Preferably, the fitting further comprises a mounting sleeve which is separated from the can by an air gap and a gasket.

Advantageously, the fitting is adapted as a light fitting and configured to receive a lamp.

Conveniently, the fitting is adapted as a sensor and configured to receive a sensor.

Preferably, the sensor is a passive infra-red sensor.

Preferably, the tubular can includes an end cover and the end cap is secured to cover an aperture though the end cover.

Advantageously, the one or more ventilation apertures are substantially radial ventilation slots.

Another aspect of the present invention provides a method of constructing an electrical fitting comprising: providing a tubular can with first and second opposing ends and adapted to receive at least part of an electrical unit through an opening at the first end; providing an end cap; and securing the end cap to cover an opening at the second end of the tubular can, wherein the end cap defines one or more elongate ventilation slots and is formed from an intumescent material such that the end cap inhibits the transmission of fire through the light fitting through the or each ventilation aperture.

Preferably, providing an end cap comprises providing an end cap which is substantially self-supporting and/or rigid.

Advantageously, securing the end cap to cover the opening at the second end of the tubular can comprises at least partially receiving the end cap in the tubular can.

Conveniently, securing the end cap to cover the opening at the second end of the tubular can comprises at least partially receiving the tubular can in the end cap.

Preferably, the method further comprises providing an annular cuff fitted around the end cap.

Conveniently, providing an end cap comprises providing an end cap constructed out of an intumescent material which comprises a thermoplastic mixed with an intumescent powder.

Preferably, providing an end cap comprises providing an end cap constructed out of an intumescent material which comprises PVC, ABS, or polyethylene mixed with an intumescent powder.

Advantageously, the method further comprises providing a face ring, attaching the face ring to the first end of the tubular can to provide a thermal break between an extreme end of the light fitting and the tubular can.

Conveniently, providing an end cap comprises providing end cap which comprises an end wall and a perimeter wall which extends from a perimete of the end wall.

Preferably, providing an end cap comprises providing an end cap which i substantially cup shaped.

Advantageously, securing the end cap to the tubular can comprises press-fitting the end cap onto the tubular can.

Preferably, the method further comprises providing a mounting sleeve which is separated from the can by an air gap and a gasket.

Preferably, the sensor is a passive infra-red sensor.

Preferably, providing a tubular can comprises providing a can including an end cover and the end cap is secured to cover an aperture though the end cover.

Advantageously, providing an end cap comprises providing an end cap with one or more ventilation slots which are substantially radial ventilation slots Another aspect of the present invention provides kit of parts for the construction of an electrical fitting, wherein the kit includes: a tubular can with first and second opposing ends, the tubular can being adapted to receive a least part of an electrical unit through an opening at the first end; and an end cap configured to be secured to cover an opening at the second end of th: tubular can, wherein the end cap defines one or more elongate ventilation slots and is formed from an intumescent material such that, when secured tr the tubular can, the end cap inhibits the transmission of fire through the light fitting through the or each ventilation aperture.

Another aspect of the present invention provides a cap for an electrical fitting wherein the cap defines one or more ventilation apertures and is constructed out of an intumescent material which comprises an intumescent powder mixed with PVC, ABS, or polyethylene.

Preferably, one or more of the one or more ventilation slots comprises a substantially radial slot.

Another aspect of the present invention provides an electrical fitting comprising: a main body including an intumescent material portion which defines at least one elongate ventilation slot, wherein the intumescent material portion is injection moulded intumescent material, and the transmission of fire through the at least one ventilation slot is hindered by the intumescent material.

Another aspect of the present invention provides, an electrical fitting comprising a main body including at least one elongate ventilation slot defined by a substantially self-supporting and/or rigid intumescent material such that, in the event of a fire, the transmission of fire through the ventilation aperture is hindered.

Another aspect of the present invention provides a lamp soGket for use with a lamp fitting, the lamp socket comprising: a main body; a lamp connector socket housed in the main body; and an abutment arrangement secured to and spaced apart from the main body such that a lamp of a first type can bE; connected to the lamp connector but a lamp of a second type abuts againsi the abutment member and is spaced apart from the lamp connector, whereir' the first and second type of lamp have substantially the same form of lamp connector.

Preferably, the main body and abutment arrangement are integrally formed.

Another aspect of the present invention provides a lamp socket and a fitting.

Another aspect of the present invention provides a method further comprising the step of fitting a lamp socket to the light fitting.

Another aspect of the present invention provides an electrical fitting for attachment to a panel, the fitting comprising: a can configured to receive an electrical device; a mounting sleeve attached to the can such that the can is at least partially received by the mounting sleeve, a main wall of the can being substantially spaced apart from a main wall of the mounting sleeve, wherein the mounting sleeve is configured to be mounted to an aperture in a panel and, in combination with the can, is adapted to cover the aperture in the panel for restricting the transmission of fire through the aperture.

Preferably, the main wall of the can and the main wall of the mounting sleeve are substantially concentric.

Advantageously, the main wall of the mounting sleeve extends along part of a length of the main wall of the can.

Conveniently, the mounting sleeve and can are in connected to each other a one end thereof.

Preferably, an attachment arrangement is provided on the mounting sleeve, the attachment arrangement being configured to secure, at least partially, th' fitting to the panel.

Another aspect of the present invention provides a cap for an electrical fitting wherein the cap defines one or more substantially elongate ventilation slots and is constructed out of an intumescent material.

Preferably, the intumescent material is a polymer based material.

Advantageously, the intumescent material comprises an intumescent powder mixed with a polymer.

In order that the present invention may be more readily understood, and so that further features thereof may be appreciated, embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings in which: Figure 1 shows an exploded view of a light fitting in accordance with an embodiment of the invention; Figure 2 shows a view of the light fitting fitted to a panel; Figure 3 shows an exploded view of a light fitting in accordance with an embodiment of the invention; Figure 4 shows an embodiment of the present invention; Figure 5 shows an end cap from a first perspective; Figure 6 shows an end cap from a second perspective; Figure 7 shows a cuff of embodiment of the present invention; Figures 8a-d show an embodiment of the present invention; Figure 9 shows an embodiment of the present invention; Figure 10 shows an embodiment of the present invention; Figures 11-14 show an embodiment of the present invention; and Figures 15, 16 and 17 show an embodiment of the present invention.

With reference to figure 1, a light fitting 1 in accordance with an embodiment of the present invention is adapted to be fitted to a ceiling 2 or other panel 2 (such as a wall panel) -see figure 2.

The light fitting 1 may be of the type generally known as a downlight. The light fitting 1 comprises a tubular can 3. The tUbular can 3 has an outer wall 4 which is preferably constructed out of steel. The outer wall 4 may be anodised or painted black.

Two clips 5 are preferably provided on the outer wall 4 of the can 3 and extend away from the can 3. These clips 5, if provided, are configured to secure the light fitting 1 to a panel 2 to which the light fitting 1 is to be fitted -the form of these clips can vary and suitable clips are known to those skilled in the art (such as spring-clips).

The outer wall 4 is preferably 1 mm thick, or less, and may have a cvcular cross-section. The can 3 therefore has the appearance of a hollow cylinder.

The can 3 has a first end 7 and a second end 8. Both ends 7,8 of the can 3 are substantially open ends. The two ends 7,8 of the can 3 oppose each other across a length of the can 3.

The first end 7 of the can 3 is adapted to receive at least part of a lamp 9 therethrough. The length of the can 3 is preferably greater than the length of the lamp 9 such that, when the lamp 9 is fitted to the light fitting 1, a transmission surlace of the lamp 9 is adjacent the first end 7 of the can 3.

An end cap 10 is provided and the second end 8 of the can 3 is configured to receive or be received by the end cap 10. In other words, the end cap 10 is configured to cover the open second end 8 of the can 3.

In an embodiment, the end cap 10 comprises a cup-shaped main body 11.

The cup-shaped main body 11 has an end wall 12 and a perimeter wall 13 extending from the end wall 12. The end wall 12 may be circular and the perimeter wall 13 may, therefore, be a circumferential wall 13. The perimeter wall 13 extends away from the end wall 12 of the end cap 10 in a direction which is substantially perpendicular to a plane of the end wall 13. The end cap 10 forms, therefore, forms a cup-like structure -with the end wall 13 and perimeter wall 13 defining a recess in the end cap 10.

The end cap 10 may have an outer diameter which is substantially the same as or marginally smaller than a diameter of the open second end 8 of the can 3. Thus, the end cap 10 may be secured to the can 3 such that it is at least partially received by the can 3. In an embodiment, an internal diameter of the end cap 10 (i.e. a diameter of the recess) is marginally larger than the diameter of the second end 8 of the can 3. Thus, the end cap 10 may be secured to the can 3 such that it surrounds at least part of the outer wall 4 of the can 3 (i.e. the end cap 10 may receive the part of the can 3). In an embodiment, a part of the end cap 10 surrounds part of the oUter waIl 4 of the can 3 and a part of the end cap 10 is received inside the can 3. Thus, there is preferably an overlap between the extreme second end 8 of the can 3 and the end cap 10.

One or more apertures 14 are provided through an entire depth of the end surface 12 of the end caplO. The one or more apertures 14 are provided for ventilation and are preferably round but may be any shape. The or each aperture 14 is preferably less than 5mm in diameter and may be less than 3mm in diameter.

One or more further apertures 15 may be provided through an entire depth of the perimeter wall 13 of the end cap 10. The or each further aperture 15 is preferably substantially rectangular in shape such that the or each further aperture 15 forms a slit through the perimeter wall 13 of the end cap 10.

Preferably, two or more further apertures 15 are provided and these further apertures 15 have a substantially uniform distribution around the perimeter wall 13 of the end cap 10.

The end cap 10 is, in an embodiment, attached to the can 3 in a press-fitting arrangement -although other attachment arrangements are envisaged. In an embodiment, one or more resiliently biased fingers 16 extend from the end waIl 12 of the end cap 10. The or each finger 16 may be located in a recess or hole in the perimeter wall 13 of the end cap 10. The or each finger 16 may be defined by a pair of indentations or channels through the perimeter wall 13 of the end cap 10. Preferably, the or each finger 16 is integrally formed with the end cap 10. The or each finger 16 may have a length which substantially equal to a length of extension of the circumferential wall 13 from the end wall 12 of the end cap 10.

In an embodiment, two or more fingers 16 are provided and the fingers 16 arc substantially uniformly arranged around the outer perimeter wall 13 of the end cap 10.

A nodule (not shown) may be provided at a free end of the or each finger 16.

Each nodule may project from its respective finger 16 in a direction which is substantially parallel with the plane of the end wall 12. Each nodule may project into the recess of the cup-shaped end cap 10 or in the opposing direction -depending on the specific intended arrangement of the end cap 10 and can 3 (as will be appreciated).

One or more holes 17 are provided in the outer wall 4 of the end cap 10. The or each hole 17 is configured such that, when the end cap 10 is fitted to the can 3, the or each finger 16 is aligned with a respective one of the one or more holes 17 and at least partially protrudes into the hole 17 -if a nodule is provided on the free end of the finger 16, the nodule is configured to protrude (at least partially) into the hole 17. Thus, in an embodiment, the end cap 10 may be partially received by the second open end 8 of the can 3 such that the or each finger 16 at least partially projects into a respective hole 17 from within the can 3. In an altemative embodiment, the end cap 10 may partially surround part of the second open end 8 of the can 3 such that the or each finger 16 at least partially projects into a respective hole 17 from outside of the can 3.

It will be appreciated that the or each finger 16 and the associated hole 17 or holes 17 comprise an attachment arrangement which is configured to secure the end cap lOto the can 3.

In an embodiment, a plate 18 extends from the end cap 10. The plate 18 is configured to be coupled to an electrical connection unit 19 which may he covered by a cover 20 (which may be attached to the plate 18 by a scre 20a). The plate 18 may include a strain relief arrangement 18a. Together the plate 18, electrical connection unit 19 and cover 20 form an electrical connection block though which electricity can be supplied to the light fitting 1. The plate 18 preferably is attached to and extends away from the end cap in a direction which is substantially parallel with the end wall 12 of the end cap 10. The plate 18 may be integrally formed with the end cap 10.

In an embodiment, the plate 18 is attached to and extends away from the outer wall 4 of the can 3 in a direction which is substantially perpendicular to a longitudinal axis of the can 3.

A lamp socket 21 is positioned within the can 3 towards the second open end 8 thereof. The lamp socket 21 is configured to receive a lamp 9. The lamp socket 21 is preferably suitable to receive a GUi 0 lamp connector. The lamp socket 21 may be coupled to the can 3, the end cap 10 or both. The lamp socket 21 is, in any event, in electrical communication with the electrical connection unit 19 such that electricity supplied to the light fitting 1 through the electrical connection unit 19 can be used to power the lamp 9 held by the light fitting 1.

At the first open end 7 of the can 3 a face ring 22 is provided. The face ring 22 has a mount portion 23 and a face plate 24. The mount portion 23 is shaped and configured for attachment to the first open end 7 of the can 3. In the case of the depicted embodiment, the can 3 has a circular cross-section and, therefore, the mount portion 23 in this embodiment also has a circular.

cross-section. The mount portion 23 is preferably a hollow cylindrical stub which is configured to fit into the first open end 7 of the can 3. One or more clips 25 may be provided around the mount portion 23. The or each clip 25 is configured to mate with a corresponding mating point 26 in the outer wall 4 of.

the can 3. The or each mating point 26 may comprise a recess in the outer waIl 4 of the can 3 or a hole through an entire depth thereof. The or each clip is preferably resiliently biased towards a locking position such that when the mounting portion 23 of the face ring 22 is pushed into the can 3 (during the construction process) the or each clip 25 engages and mates with a respective mating point 26 to lock the face ring 22 into position with respect to the can 3.

In an embodiment, two or more clips 25 are provided and the clips 25 are uniformly distributed around the mount portion 23. Each of the clips 25 has a corresponding mating point 26 in the can 3.

In an embodiment, an external diameter of the mount portion 23 is less than an internal diameter of the can 3 such that at least part of the mount portion 23 is received by the can 3. In an embodiment, an internal diameter of the mount portion 23 is greater than an external diameter of the can 3 such that at least part of the can 3 is received by the mount portion 23 and at least part of the mount portion 23 surrounds at least part of the first end 7 of the can 3.

The mount portion 23 of the face ring 22 has a ridge 31 which is configured to abut against an extreme end of the first end 7 of the can 3 such that part of the mount portion 23 (when the face ring 22 is fitted to the can 3) extends beyond the extreme end of the can 3. This exposed section of the mount portion 23 is intended to abut against the panel 2 to which the light fitting 1 is fitted. Thus, the can 3 is intended to be substantially separated from direct contact with the panel 2. The face ring 22, therefore, acts as a thermal break between the can 3 (which may get hot during operation) and the panel 2. * The ridge 31 may delineate between a part of the mount portion 23 with a larger external diameter than another part. The part of the mount portion 2 with the larger diameter is, in this embodiment, the part of the mount portk:i 23 which is adjacent the face plate 24.

The face plate 24 of the face ring 22 comprises an annular disc which extends from the mount portion 23 to form an outwardly extending flange. This flange is preferably circular in cross-section and has a maximum diameter which is greater than a maximum diameter of the outer wall 4 of the can 3.

The face ring 22 defines an aperture which is aligned (substantially) with hollow cavity of the can 3 -when the face ring 22 is fitted to the can 3. The face ring 22 is such that a lamp 9 can be passed through the aperture defined by the face ring 22 and into the can 3 -it can then be secured to the lamp socket 21. Thus, when a lamp 9 is fitted to the light fitting 1 in this manner, a light transmission surface of the lamp 9 will preferably be adjacent the face ring 22.

Two lock recesses 29 are provided in face ring 22 (they may be provided in the face plate 24 or mount portion 23). The lock recesses 29 are configured to receive respective parts of a lock wire (not shown) which may be inserted into the light fitting 1 to hinder the movement of a lamp 9 out of the fitting 1.

A decorative face plate 27 is provided. The decorative face plate comprises an annular disc defining an annular recess 28. The annular recess 28 is suitableto receive at least part of the:face ring 22 of the light fitting 1 when the light fitting 1 is constructed and fitted to a panel 2. Thus the decorative face plate 27 may substantially hide the face ring 22 from the view of an occupant of a room in which the light fitting 1 has been fitted. The decorativr face plate 27 may be fitted to the face ring 22 by a press-fitting, a screw fitting, or a twist-and-lock-fitting (e.g. the use of corresponding mateabie threads or elements).

The decorative face plate 27 may include a ridge 30 around an internai surface thereof (the internal surface defining an aperture through the annular decorative face plate 27). The ridge 30 may be configured to support a lens (not shown). The lens may be clear or coloured glass or transparent plastic or may be a translucent plastic or glass material.

The end cap 10 is preferably an integrally formed unit (i.e. formed as a single item). The end cap 10 is preferably an injection moulded cap. The end cap is manufactured out of an intumescent material comprising a thermoplastic material which has been mixed with an intumescent powder where the temperature of intumescence of the powder (i.e. the temperature at which substantial intumescence begins) is greater then the plastic state temperature of the thermoplastic material. The thermoplastic material may have a plastic state temperature of over about 12000 or over about 140°C but below about 195°C. The intumescent material preferably has a temperature of intumescence which is greater than about 195°C. The thermoplastic may be Polyvinyl chloride (PVC), Acrylonitrile butadiene styrene (ABS), or polyethylene.

A suitable intumescent material may be the product marketed as INTUPLAS (registered trade mark) by Pyrophobic Systems Limited. Using such materials it is possible to form an end cap 10 which is substantially rigid and does not, therefore, require the complicated attachment arrangements present in the prior art. The end cap 10 is self-supporting in the sense that It does not require, for example, the can 3 in order for it to hold its shape and form. The intumescent material therefore possesses many of the important physicai properties of the thermoplastic used in its manufacture. This aIlow conventional injection moulding techniques to be used to form the end cap 10.

The plate 18 may be formed from a different material.

The face ring 22 is preferably formed out of a thermoplastic with a high plastic state temperature. In an embodiment, the face ring 22 is formed out of an intumescent material which may be an intumescent material as described above.

It will be appreciated that the light fitting 1 described herein may be a downlight suitable to be fitted to a ceiling or may be a light fitting which is suitable to be fitted to some other form of panel.

The main steps of the construction of the light fitting 1 can be summarised as follows: the end cap 10 is secured over the second open end 8 of the can 3, the lamp socket 21 is secured to the can 3 or end cap 10, and the face ring 22 is secured to the first open end 7 of the can 3. At least some of the complicated construction processes of the prior light fittings of this type are therefore avoided.

To fit the light fitting 1 to a panel 2, a hole is prepared in the panel. The light fitting 1 is then inserted into the hole, end cap 10 first. The face plate 24 of the face ring 22 abuts against the panel and the clips 25 are secured to the panel to hold the light fitting in place. An electrical supply is connected to the electrical connection unit 19. The decorative face plate 17 is fitted to the face ring 22 and a lamp 9 is fitted to the lamp socket 21.

In the event of a fire, the end cap 10 swells (as it is constructed from an intumescent material) and this substantially closes the apertures 14 anc further apertures 15 in the end cap 10. Thus, the transmission or progress ol fire though the light fitting 1 is hindered (i.e. the transmission of fire from the first end 7 of the can 3 through the apertures 14 and further apertures 15 is hindered).

It will, of course, be appreciated that the apertures 14 and further apertures are ventilation apertures.

With reference to figures 3 to 8, other embodiments of the present invention comprise a light fitting 1 (like reference numerals will be used for like features). The light fitting 1 comprises a substantially tubular can 3 having an outer wall 4.

The can 3 has a first end 7 and a second end 8. A length of the can 3 is defined by the distance between the extreme first end 7 of the can 3 and the extreme second end 8 of the can 3 -the two ends 7,8 of the can 3 oppose each other across the length of the can 3.

The can 3 is adapted to receive at least part of a lamp 9 therein.

The first end 7 of the can 3 is configured to be fitted to a support ring 41. The support ring 41 is preferably formed out of pressed steel. The support ring 41 is generaHy annular and has an internal diameter which is larger than the external diameter of the can 3 such that an outer wall of the support ring 41 may fit around the first end 7 of the can 3. A circumferential lip is provided around the support ring 41 at one end of the outer wall thereof. The circumferential tip has an internal diameter which is less than the external diameter of the can 3 such that the lip abuts against the extreme first end 7 of the can 3 (when constructed).

A gasket 35 is provided which generally comprises an annular member which has a diameter which is substantially similar to a diameter of the support ring 41.

The gasket 35 configured to be abutted against the support ring 41. The gasket 35, support ring 41, and first end 7 of the can 3 are configured to be received by a mounting sleeve 30 (which, equally, is configured to receive the gasket 35, support ring 41, and first end 7 of the can 3).

The mounting sleeve 30 comprises a mating portion 33 and a face plate 34.

The mating portion 33 in this embodiment is similar in general function to the mount portion 23 which is described above. However, the mating portion 33 in this embodiment comprises a tubular body which extends from the face plate 34 and which has an internal diameter which is, larger than an external diameter of the can 3 and an external diameter of the support ring 41. Thus, the can 3 (and support ring 41) may be received by the mating portion 33 of the mounting sleeve 30. An internal abutment protrusion (not shown) within the tubular body of the mating portion 33 is configured such that it reduces the internal diameter of the mating portion 33 (i.e. the abutment protrusion protrudes into the tubular body of the mating portion).

The abutment protrusion may be around an entire inner circumferential surface of the tubular body of the mating portion 33. In an embodiment, the abutment protrusion, in fact, comprises a series of protrusions. In an embodiment, such as the depicted embodiment, the protrusion comprises a necked portion 36 of the mounting portion of the mounting sleeve 30. The necked portion 36 comprises a part of the mating portion 33 which has a smaller inner diameter than the rest of the tubular body of the mating portion 33. The necked portion 36 can be seen in figure 4 from the outside of th! mounting sleeve 30.

When fitted to the mounting sleeve 30, the gasket 35 abuts against the abutment protrusion and is sandwiched between the abutment protrusion and the support ring 41. Thus, the extreme first end 7 of the can 3 is spaced apart from the mounting sleeve 30. As the internal diameter of the mating portion 33 of the mounting sleeve 30 is larger than the external diameter of the can 3, the outer waIl 4 of the can 3 is not normally in contact with the mounting sleeve 30 and is spaced apart therefrom. Thus, the gasket 35 acts as a thermal break between the can 3 and the mounting sleeve 30. In addition, the gasket 35 acts as a seal between the interior of the can 3 and the space between the can 3 and the mounting sleeve 30. Furthermore, the mounting sleeve 30, which may abut against a panel to which the fitting us fitted, is substantially thermally isolated from the can 3.

The face plate 34 is preferably integrally formed with the mount portion 33 and is comparable to the face plate 27 of the above described embodiment.

Thus, it will be appreciated that aspects of the face plate 27 and face ring 23 of the above described embodiment have been combined in this embodiment in a single feature.

The face plate 34 preferably defines an annular channel 43 around the mounting sleeve 34 which is configured to receive a heat resistant gasket 44.

The heat resistant gasket 44 is preferably formed from heat resistant silicon material. When the light fitting 1 is fitted to a panel, the heat resistant gasket 44 is sandwiched between the face plate 33 and the panel to provide a seal to hinder the progression of fire therethrough.

In this embodiment, the mounting sleeve 30 is preferably entirely constructed out of an aesthetically pleasing material such that no separate face pI:r (such as face plate 27) is required. The material may, for example, be chrorn.

plated, may be constructed out of plastic, or may be polished.

One or more (preferably two) rivets 42 may be used to secure the can 3 ar mounting sleeve 30 together. The rivet or rivets 42 may pass through th mounting sleeve 30, the support ring 41 and the can 3.

In an embodiment, at the second end 8 of the can 3 is an end cap 10. The end cap 10 in this embodiment differs from the end cap 10 depicted in, for

example, figure 1.

The end cap 10 of this embodiment can be seen in figures 3 to 7. The end cap 10 comprises an end wall 12 and a perimeter wall 13 in a similar manner to the embodiment of figure 1. However, in this embodiment, the perimeter wall 13 has an external diameter which is marginally smaller than an internal diameter of the can 3 at the second end 8 thereof. Thus, the perimeter wall 13 is configured to be received by the tubular body of the can 3 at the second end 8 of the can 3. The end cap 10 is preferably held secured to the can 3 is a press-fit arrangement. As such, one or more circumferential ribs 37 may be provided around an outer surface of the perimeter wall 13. The or each rib 37 may be deformable such that a when an end cap 10 is secured to a can 3, one or more of the or each ribs 37 deforms and the end cap 10 is secured to the can 3 -thus, a tight fit between the end cap 10 and the can 3 is provided.

The perimeter wall 13 may extend from the extreme perimeter of the end wall 12. The perimeter wall 13 may be such that an external diameter of the perimeter. wall 13 is smaller than a diameter of the end wall.12 -thus, a lip of.

the end wall 12 extends beyond the perimeter wall 13 in substantially the same plane as the end wall 12.

As with the end cap 10 of the embodiment of figure 1, the end cap 10 of thk embodiment includes one or more apertures 14 through the end wall 12 thereof and the end cap 10 is formed out of the same type of material as th' end cap 10 described above.

The end cap 10 of this embodiment includes an electrical connection unit attachment arrangement 38. This arrangement 38 is configured to be secured to an electrical connection unit 19 which has a comparable function to the electrical connection unit 19 of the embodiment of figure 1. The arrangement 38 preferably comprises one or more projections which are configured to be received by correspondingly shaped notches in an electrical connection unit 19. The arrangement 38 is such that an electrical connection unit 19 can be secured to the end cap 10 by a press-fit type arrangement.

Extending from the end waIl 12 of the end cap 10 in generally the same direction as the perimeter wall 13 is a lamp socket attachment arrangement 39. The attachment arrangement 39 is configured to be secured to a lamp socket 21 -so that the lamp socket 21 will be held within the tubular body of the can 3 in the constructed light fitting 1. The lamp socket attachment arrangement 39 may extend from approximately the centre of the end wall 12.

The lamp socket attachment arrangement 39 preferably comprises two substantially cylindrical extensions which extend away from the end wall 12 and have respective first and second lengths. The first and second lengths may be the same or one of the extensions may be longer than the other. The extensions preferably extend in a direction which is perpendicular to a plane of the end wall 12 of the end cap 10 and in the same direction as the direction of extension of the perimeter wall 13 -such that when the end cap 10 is fitted to the can 3, the attachment arrangement 39 extends into the cavity defined by the tubular body of the can 3.

The lamp socket attachment arrangement 39 (including the extensions) is preferably integrally formed with the rest of the end cap 10.

In an embodiment, the end cap 10 is provided with a cuff 40 (see figure 7).

The cuff 40 comprises a ring configured to receive the end cap 10. The cuff may be configured to be fitted to the can 3 in a press-fit arrangement. As such, the cuff 40 may have an external diameter which is less than the internal diameter of the can 3 at the second end 8 thereof such that the cuff can fit within the can 3 (at least partially). An external surface of the cuff may include one or more projections which are configured to abut against the inside of the can 3 to assist in securing the cuff 40 to the can 3.

In an embodiment, the cuff 40 has an internal diameter which is larger than the external diameter of the can 3 at the second end thereof 8 such that the cuff 40 can fit over the extreme second end 8 of the can 3. An internal surface of the cuff 40 may include one or more projections which are configured to abut against the outer waIl 4 of the can 3 to assist in securing the cuff 40 to the can 3.

In an embodiment, a gasket (not shown) is provided and configured to be sandwiched between the cuff 40 and the can 3.

Two clips 5 for securing the light fitting 1 to panel 2 are provided on an outer surface of the mounting sleeve 30.

It will be appreciated that the fitting need not include any welds. The parts of the fitting 1 may be press-fitted together. Thus, it will be appreciated that the construction of the can 3 is simplified when compared to the embodiment cf figure 1.

The main steps of the construction of the light fitting 1 can be summarised as follows: the end cap 10 is secured over the second open end 8 of the can, the lamp socket 21 is secured to the can 3 or end cap 10, and the mountinç sleeve 30 is secured to the first open end 7 of the can 3. A gasket 35 may also be fitted to the first end 7 of the can 3 (between the extreme first end 7 of the can 3 and the mounting sleeve 30). At least some of the complicated construction processes of the prior light fittings of this type are therefore avoided. Other aspects of the construction of the light fitting 1 will be apparent from the description of the light fitting 1.

An embodiment of the present invention is depicted in figures 9 and 10. This embodiment comprises a light fitting 1 which is similar in many respects to the light fittings 1 described above (and, as such, like reference numerals will be used for like features).

The light fitting 1 comprises a can 3 with a substantially tubular wall 4. A length of the can 3 is defined by the distance between an extreme first end 7 of the can 3 and an extreme second end 8 of the can 3.

The can 3 is configured to receive a lamp 9 therein.

The first end 7 of the can 3 is configured to be fitted to a support ring 41. The support ring 41 is preferably formed out of pressed steel. The support ring 41 is generally annular and has an internal diameter which is larger than the external diameter of the can 3 such that an outer wall of the support ring 41 may fit around the first end 7 of the can 3. A circumferential lip is provided around the support ring 41 at one end of the outer wall thereof. The circumferential lip has an internal diameter which is less than the external diameter of the can 3 such that the lip abuts against the extreme first end 7 of the can 3 (when constructed).

The mounting sleeve 30 comprises a mating portion 33 and a face plate 34.

The mating portion 33 in this embodiment is similar in general function to the mount portion 23 which is described above. However, the mating portion 33 in this embodiment comprises a tubular body which extends from the face plate 34 and which has an internal diameter which is larger than an external diameter of the can 3 and an external diameter of the support ring 41. Thus, the can 3 (and support ring 41) may be received by the mating portion 33 of the mounting sleeve 30.

In an embodiment, such as the depicted embodiment, the mounting sleeve includes a necked portion 45 towards an end of the mating portion 33 which is adjacent or substantially adjacent the face plate 34.

As will be appreciated aspects of this embodiment are similar to the corresponding aspects of the embodiment of figure 3 and that part of the above description (among other parts) is generally applicable to this embodiment too.

The face plate 34 preferably defines an annular channel 43 around th mounting sleeve 34 which is configured to receive a heat resistant gasket 44 and a fibre gasket 46. The heat resistant gasket 44 and/or the fibre gasket 4' are preferably formed from heat resistant material. When the light fitting 1 is fitted to a panel, the heat resistant gasket 44 and fibre gasket 46 are sandwiched between the face plate 33 and the panel to provide a seal to hinder the progression of fire therethrough.

In this embodiment, the mounting sleeve 30 is preferably entirely constructed out of an aesthetically pleasing material such that no separate face plate (such as face plate 27) is required. The material may, for example, be chrome plated, may be constructed out of plastic, or may be polished.

One or more (preferably two) rivets 42 may be used to secure the can 3 and mounting sleeve 30 together. The rivet or rivets 42 may pass through the mounting sleeve 30, the support ring 41 and the can 3.

In this embodiment, an electrical connection unit 19 is supported by an L-shaped arm 47 which extends from the mounting sleeve 30 (and is an inverted orientation). The L-shaped arm 47 is preferably coupled to the mounting sleeve 30 by a rivet 49 which extends through the mounting sleeve and arm 47.

The L-shaped arm preferably has a pair of tags 48 which extend therefrom generally towards a central axis of the light fitting 1. The pair of tags 48 is configured such that the tags 48 abut against an extreme end surface of the mounting sleeve 30 when constructed. The tags 48, therefore, help to limit or substantially prevent rotation of the arm 47 about the rivet 49.

In an embodiment, at the second end 8 of the can 3 is an end cover 50. Th end cover 50 in this embodiment differs from the end cap 10 depicted in, t example, figure 1 or figure 3.

The end cover 50 comprises a tubular perimeter wall 51 and an end wall 51 The tubular perimeter wall 51 is configured to be fitted over or inside the er: 8 of the can 3 and may be held in place by a suitable attachment means such as a rivet 55.

The end wall 51 of the end cover 50 defines an aperture 53 which is configured to receive a bung 54.

The end cover 50 is preferably constructed out of the same material as the can 3 and may be constructed out of steel.

The bung 54 is constructed out of an intumescent material (such as an intumescent material as described above). For example, the intumescent material (of this and other embodiments) may be a polymer based material.

The bung 54 is shown in more detail in figures 11-14.

The bung 54 comprises a disk 56 and a cylindrical protrusion 57 which extends from the disk 56. One or more (and preferably a plurality) of slots 58 are defined by the bung 54 and extend through an entire depth thereof.

A central aperture 59 is provided through an entire depth of the centre of the bung 54.

The disk 56 generally, has a diameter which is larger than a diameter of the aperture 53 to which the bung 54 is to be fitted.

The cylindrical protrusion 57 generally has a diameter which is less than diameter of the aperture 53 defined by the end wall 51 of the end cover 50 The cylindrical protrusion 57 may include a rim (which could take the form o a series of protrusions forming a ring-like structure) which has a diamete which is larger than the diameter of the aperture 53 to which the bung 54 is to be fitted. The rim may be elastically deformable such that the cylindrical protrusion 57 can be pressed into the aperture 53. Thus, the bung 54 may be held in place on the end cover 50 by the disk 56 abutting one side of the end cap 52 and the rim abutting the opposing side of the end cover 50. The rim may be barbed to resist removal of the bung 54 from the end cover 50.

The one or more slots 58 provide ventilation and are preferably generally radial slots 58. The central aperture 59 may be used, for example, to carry electrical supply cables therethrough.

A lamp socket support arm 60 may be provided. The lamp socket support arm 60 may be generally U-shaped with two extensions of the arm 60 being attached to the end cover 50 and supporting a base section of the arm 60 spaced apart from the end cover 50. To this end, rivets 61 may be used as a suitable attachment mechanism to secure the arm 60 to the end cover 50.

The lamp socket support arm 60 is further configured to receive a lamp socket 21.

It will be appreciated that the fitting need not include any welds. The parts of the fitting 1 may be press-fitted together. Thus, it will be appreciated that the construction of the can 3 is simplified when compared to the embodiment of figure 1.

With reference to figure 15, an embodiment of the present inventic comprises a light fitting 1 which has been adapted to be fitted to a ceiling 2 or other panel 2 (such as a wall panel). The light fitting 1 shares many commo features with the light fitting of figure 1 and the light fitting of figure.

Accordingly, common reference numerals will be used, in some instances, for corresponding features. It will be appreciated that features of the embodiments depicted in figures 1, 9 and 15 can be interchanged and mixed in order to arrive at a light fitting 1 having a combination of the features of two or more of the embodiments.

The light fitting 1 may be of a type generally known as a downhight and comprises a tubular can 3. The tubular can 3 has an outer wall 4 which is preferably constructed out of steel. As with the embodiment disclosed in figure 1, the outer wall 4 may be anodised or painted black.

Two clips 5 are provided on either side of the outer wall 4 of the can 3 and extend away from the can 3 -these clips 5 are generally similar to the clips 5 shown in figure 1. Please note that in figure 15 only one clip 5 is visible and the other clip 5 is located on the outer waIl 4 of the can 3 and is diametrically opposed to the clip 5 which is visible in figure 15. Both clips 5 extend away from the can 3.

The outer wall 4 may have a construction which is generally as described herein in relation to the other embodiments of the invention. The can 3, therefore, is preferably a substantially hollow cylinder. Unlike the embodiments depicted in figure 1 all the embodiments depicted in figure 9, an end wall of the can 3 is integrally formed with the outer wail 4 of the can 3.

Thus, compared to the embodiment shown in figure 9, the end cover 50 of that embodiment is not required and the end wall 52 of that embodiment is r integral part of the can 3 in the embodiment of figure 15.

The end wall of the can 3 of the embodiment depicted in figure 15 defines a aperture which is similar (and has a corresponding function to) the apertu:' 53 of the embodiment shown in figure 9. In other words, the aperture in th.

end wall of the light fitting 1 shown in figure 15 is configured to receive a bUily 54.

A mounting arrangement 62 is provided in the outer wall 4 of the can 3 to secure one or more of the clips 5 to the can 3. The mounting arrangement 62 may comprise an arrangement 62 which is secured to the outside of the outer wall 4 -for example by welding or soldering. The attachment arrangement 62 generally comprises a mounting plate which is shaped to match the external shape of the outer wall 4. The plate includes an opposing pair of protrusions which extend towards each other and define a gap therebetween. The protrusions are spaced apart from the outer wall 4 of the can 3. A proximal end of a clip 5 includes two wire coils separated from each other across the width of the clip 5. The two wire coils are parallel and aligned with each other such that they generally share a common central axis. A hole through each of the wire coils of the clip 5 is configured to receive a respective protrusion of the mounting arrangement 62. Thus, a clip 5 may be mounted to a mounting arrangement 62 -as will be appreciated.

One or more pairs of protrusions may be provided on the mounting arrangement 62 such that a clip 5 can be removed from one pair of protrusions of the arrangement 62 and placed in a different location on a different pair of protrusions of the arrangement 62.

The can 3 has a first end 7 and a second end 8. As previously described, the second end 8 of the can 3 includes an end wall and defines an apertur" therethrough. The first end of the can 3 is a substantially open end adaptc to receive at least part of a lamp 9 therethrough. The lamp 9 may be an LET (light emitting diode) based lamp 9. One or more cooling fins may b provided around a portion of the lamp (which may, in an embodiment, forr: -part of the light fitting 1). The or each cooling fin is preferably a metal f which extends generally radially away from a central longitudinal axis of the lamp 9 from an outer wall thereof.

The lamp 9 is configured for attachment to a lamp socket 21. The lamp socket 21 includes electrical connectors (e.g. wires) for connecting the lamp socket 21 to an electrical connection unit 19.

An L-shaped arm 47 (similar to the L-shaped arm described in relation to the embodiment depicted in figure 9) is provided. The L-shaped arm 47 is secured to the main wall 4 of the can 3 such that a support plate of the arm 47 extends substantially perpendicular to a longitudinal axis of the can 3 (with a mounting plate of the arm 47 extending substantially parallel to the outer wall 4 of the can 3). The mounting plate of the L-shaped arm 47 may be attached to the can 3 by the use of one or more rivets 63. Alternatively, the mounting plate of the L-shaped arm 47 may be welded or adhered to the can 3 -or secured by any other suitable arrangement.

The L-shaped arm 47 is intended to support one or more electrical components. These electrical components may include an electrical connection unit 19, a cover 20, a mechanical support 64, a strain relief attachment member 65, and an attachment screw 66.

The mechanical support 64 is attached to the support plate of the L-shaped arm 47 and, in turn, supports the electrical connection unit 19. The cover 20 is shaped in size such that it may fit over the electrical connection unit 19 and all or part of the mechanical support 64. An electrical cable (not shown) maj 0 be connected to the mechanical support 64 and strain relief may be provide: by the strain relief member 65 -which may secure the cable between the strain relief member 65 and the mechanical support 64. The screw 66 mi" pass through the cover 20, through the electrical connection unit 19, throu the mechanical support 64 and through an appropriately sized and arranged aperture in the support plate of the L-shaped arm 47.

At a first end 7, of the light fitting 1, a bezel intumescent seal 67 is provided.

The bezel intumescent seal 67 defines an aperture which corresponds with the cross-sectional shape of the can 4 towards the first end 7. The bezel intumescent seal 67 may be an annular seal. The bezel intumescent seal 67 is, in an embodiment, configured to be pressed against the end of the side wall 4 of the can 3 at the first end 7 thereof. To this end, the bezel intumescent seal 67 may be sandwiched between the can 3 and a silicone bezel seal 68 when the light fitting 1 is constructed. Alternatively, the bezel intumescent seal 67 may surround the outer wall 4 of the can 3 and may not be pressed against the end of the side wall 4. In other words, the aperture defined by the bezel intumescent seal 67 may be larger than an outer diameter of the can 3 at the first end 7 thereof -of course, the cross-sectional shape of the can 3 at the first end 7 need not be circular. The silicone bezel seal 68 may be configured to define an aperture of similar shape and size to the aperture defined by the bezel intumescent seal 67. In an embodiment a rim width of the silicone bezel seal 68 (defined between adjacent parts of the inner and outer edges thereof) is greater than a corresponding rim width of the bezel intumescent seal 67. In an embodiment, the silicone bezel seal 68 lies, in the constructed light fitting 1, around the outside of the outer wall 4 of the can 3 and is adjacent thereto; the bezel intumescent seal 67 lies on the silicone bezel seal 68 and is also located around the outer waIl 4 of the can 3 -the bezel intumescent seal 67 may be spaced apart from the outer wall 1 nf the can 3 and supported by the silicone bezel seal 68 in order to provid partial or substantial thermal isolation of the intumescent material of the bet.

intumescent seal 67 from the outer wall 4 of the can 3 to prevent the intumescent material from expanding in the absence of a fire (i.e. wher expansion of the material is not required). The silicone bezel seal &: preferably provides a seal between a front face 69 and the outer waIl 4 of the can 3. In an embodiment, the silicone bezel seal 68 is sandwiched between the can 3 and the front face 69. In an embodiment, both the bezel intumescent seal 67 and the silicone bezel seal 68 are sandwiched between the can 3 and the front face 69.

The front face 69 (similar to the face plate 34 of the embodiment depicted in figure 9) is provided to support the silicone bezel seal 68 and the bezel intumescent seal 67 and to provide an aesthetic surround to the light fitting 1.

The front face 69 comprises a decorative ring of material defining the aperture therethrough generally corresponding in size to the open end of the can 3. A tubular inner rim and one or more arms extend from the front face 69 in a direction which is generally perpendicular to a front face 69 such that the inner tubular rim and one or more arms may be inserted into the can 3 during construction of the light fitting -the or each arm preferably extends to a greater height above the decorative ring than the tubular inner rim. One or more holes may be provided in the or each arm. The holes may be arranged to correspond with similar apertures in the outer wall 4 of the can 3. Thus, the front face 69 can be secured to the can 3 through the use of one or more rivets 63 through one of the or each holes in the or each arm and through the similar aperture or apertures in the outer wall 4 of the can 3. Of course, other attachment arrangements are also possible.

The decorative ring of the front face 69 may include a recess to receive at least part of the silicone bezel seal 67.

In order to hold a lamp 9 in place inside the can 3 during operation, a Ia clip arrangement 70 is provided. The lamp clip arrangement 70 compris6 one or more components which may include a clip member 70a and blanking member 70b. The or each component of the lamp clip arrangern is preferably annular with an internal diameter which is smaller than external diameter of the lamp 9. The blanking member 7Db has an external diameter which is smaller than an internal diameter of the aperture defined by the front face 69. Thus, the blanking member 70b may be inserted into the aperture in the front face 69 and used to cover part of the lamp 9 -for example cooling fins around the outer perimeter of the lamp 9. The clip member 70a comprises a tubular clip member configured for insertion into the aperture defined by the front face 69. The tubular clip member includes one or more resiliently biased moveable portions which are configured to cooperate with one or more corresponding ridges in the inner surface of the rim of the front face 69 such that the clip member 70a may be attached to the front face 69 in a press-fit arrangement (with the moveable portions removably engaging one or more corresponding ridges). The tubular clip member is preferably surrounded by an annular wall which is generally perpendicular to the tubular clip member and extends away from a central axis of the clip member 70a. The annular wall is configured such that, in use, the wall substantially covers the interface between the tubular clip member and the front face 69.

A bung 54 which may be used in relation to a number of the embodiments of the present invention as disclosed herein is depicted in figures 16 and 17.

The bung 54 is similar to the bung 54 shownin figures 11 to 14.

In particular, the bung 54 comprises a disc of material -which may be th same material as is used to create bung 54 depicted in figures 11 to 14.

first side of the bung 54 is depicted in figure 16. The bung 54 comprises outer edge 72. In the case of a generally circular bung 54 (as depicted) this outer edge 72 is an outer circumferential edge 72 -the bung 54 may be ar shape which corresponds with an aperture in a light fitting 1 or other electric fitting to which it is intended to be fitted.

An annular perimeter surface 83 extends radially inwardly and away from the outer edge 72 of the bung 54. The outer edge 72 of the bung 54 preferably has a diameter of around 40mm. The annular perimeter surface 83 preferably has a radial depth of around 10mm. A plurality of apertures 75 are provided through the annular perimeter surface 83. The apertures 75 extend through an entire depth of the bung 54. In an embodiment, four apertures 75 are provided. The apertures 75 are preferably evenly spaced around a general perimeter of the bung 54. The apertures 75 are, in an embodiment, approximately arcuate and generally follow the shape of the outer edge 72 of the bung 54.

An annular protrusion 71 extends from an inner edge of the annular perimeter surface 83. The annular protrusion 71 preferably extends less than 2mm above the annular perimeter surface 83 and extends generally perpendicular thereto. The annular protrusion preferably has a radial depth of approximately 1 mm (i.e. from the inner edge thereof to an adjacent outer edge thereof through a radial axis of the bung 54).

The annular protrusion 71 surrounds an inner section of the first side of the bung 54. The inner section comprises a main surface which is generally parallel to and aligned with the annular perimeter surface 83.

A plurality of apertures 73, 74, are provided through an entire depth of th.

bung 54 from the first side thereof to the second side thereof. The plurality c apertures 73,74 are preferably provided through the inner section of the fir side of the bung 54.

The apertures 73, 74 include a central aperture 73 with a generally circuLar cross-sectional shape. Petal or slot apertures 74 are provided. These apertures 74 extend radially away from the central aperture 73. The slot apertures 74 extend towards the annular protrusion 71 but each have a length which is less than the distance between the central aperture 73 and the annular protrusion 71. The slot apertures 74 are spaced apart from the central aperture 73 and the annular protrusion 71. The slot apertures 74 have a length which is greater than a width thereof.

Each slot aperture 74 has a width which generally increases as the slot aperture 74 extends away from the central aperture 73. The ends of each slot aperture 74 are curved -the radius of the curved end of each slot aperture 74 near the central aperture 73 being smaller than he radius of the slot aperture 74 near the annular protrusion 71. Each slot aperture 74, in an embodiment, has a minimum width of about 2mm and a maximum width of about 5mm.

The width of each slot aperture 74, in an embodiment, may vary between these minimum and maximum values along the length thereof. A radius of an end of a slot aperture 74 may be approximately 1 mm (preferably 0.99mm) and a radius of an opposing end of the slot aperture may be approximately 2mm (preferably 2.23mm). The elongate walls of a slot aperture 74 may have an angular displacement with respect to each other of about 24° (preferably 23.84°). The general shape of the slot apertures 74 depicted in figure 17 may be described as petal shaped and the term is to be construed accordingly.

The central aperture 73 may have a diameter of about 4mm.

The provision of an elongate slot aperture 74 as a ventilation aperture h been found to be surprisingly effective. In particular, the increase size of th aperture (compared with a round aperture) increases the volume of air which can pass into and out of the can 3. As the aperture is elongate, the distance' between the two opposing side walls of the slot can be carefully controlled.

ensure that, in the event of a fire, the aperture will close sufficiently quickly (by expansion of the intumescent material). Petal shaped elongate slots have been found to be particularly effective.

Preferably, there are eight slot apertures 74 in the bung 54. However, in accordance with an embodiment, fewer than eight slot apertures 74 are provided. Similarly, in another embodiment, more than eight slot apertures 74 are provided in the bung 54. The slot apertures 74 are preferably evenly spaced around the central aperture 73 with in the inner section of the first side of the bung 54. In an embodiment, there are two or more slot apertures 74. In an embodiment, a single slot aperture 74 is provided.

With reference to figure 17, the second side of the bung 54 comprises a substantially cylindrical protrusion 76 which stands proud of an annular perimeter surface 78 of the second side of the bung 54 (preferably by about 3mm). An outer circumferential edge of the cylindrical:protrusion 76 generally.

corresponds in shape, size, and alignment with an outer circumferential edge of the annular protrusion 71 of the first side of the bung 54. Thus, the slot apertures 74 and central aperture 73 pass through the substantially cylindrical protrusion 76.

The substantially cylindrical protrusion 76 of the bung 54 is separated into a number of segments by the slot apertures 74. Segments which are not aligned with one of the apertures 75 comprise a T-shaped segment member 81. A central pillar of each T-shaped segment member extends radiafly towards the central aperture 73. A head of each T-shaped segment mernHr is arcuate and is generally parallel to the outer circumferential edge 72 of t: C bung 54. Segments which are generally aligned with one of the aprtures 75 each comprise an segment member 82 which is radially shorter than the T shaped segment members 81 and does not include a head; thus, thee segment members 82 each end within a perimeter generally defined by the heads of the T-shaped segment members 81.

An attachment projection 77 adjacent each aperture 75 extends in a direction which is generally parallel to the substantially cylindrical protrusion 76. The attachment projections 77 are substantially aligned with the perimeter generally defined by the heads of the T-shaped segment members 81 and are spaced apart from the respective end of the adjacent segment member 82.

The space defined between each attachment projection 77 and the end of the adjacent segment member 82 is such that the attachment protrusion 77 can flex with respect to the segment member 82 (each projection 77 is a resiliently biased member with a degree of flexibility).

Each attachment projection 77 is provided with an angled abutment surface such that a depth of the projection 77 tapers with distance from the annular perimeter surface 78. The most remote end of the, attachment projection 77 from the annular perimeter surface 78 is a distal end of the projection.

The angled abutment surface terminates in a notch towards a proximal end of the attachment projection 77 (which generally opposes the distal end across a length of the projection 77). Each attachment projection 77 generally has a length which substantially corresponds with a length of the respective adjacent aperture 75. The notch is sized to receive part of an edge of a sheet of material which is of a depth equal to the depth of the material used tr' construct the fitting to which the bung 54 is to be secured -e.g. the depth material used to form the end wall of the can 3 of the light fitting 1. Thus, if bung 54 may be press-fitted to a fitting such that the substantially cylindrical protrusion 76 extends through an aperture in a fitting. The attachmer projections 77 are deflected (by abutment of the angled abutment surfaces thereof with the edge of the material defining the aperture) and the material forming the fitting comes to rest in the notches. The attachment projections 77 resiliently return to an undeflected state and the material is held in place with respect to the bung 54 by the attachment projections 77.

In an embodiment, the main steps of the construction of the light fitting 1 can be summarised as follows: the bung 54 is secured to the end wall of the can 3, the electrical components and support arm 47,64,65,20,66 are attached to the can 3, the lamp socket 21 is inserted into the can 3 and connected to the connection unit 19, the bezel intumescent seal 67 and silicone bezel seal 68 are positioned with respect to the front face 69 and the front face 69 is then connected tothe first end of the can 3.

In an embodiment, the main steps of the construction of the light fitting 1 can be summarised as follows: the bung 54 is secured to the end cover 50, the end cover 50 is secured to the over the second open end 8 of the can 3, the lamp socket 21 is secured to the can 3, and the mounting sleeve 30 is secured to the first open end 7 of the can 3. A gasket 35 may also be fitted to the first end 7 of the can 3. At least some of the complicated construction processes of the prior light fittings of this type are therefore avoided. Other aspects of the construction of the light fitting 1 will be apparent from the

description of the light fitting 1.

To fit the light fitting 1 to a panel 2, a hole is prepared in the panel. The light fitting 1 is then inserted into the hole -end cap 10 first. The mounting sleve abuts against the panel and the clips 5 are secured to the panel to hold o light fitting in place. An electrical supply is connected to the elect;ai connection unit 19. Other aspects of the fitting of the light fitting 1 will be apparent from the description of the light fitting 1. It will also be apparent hat the fitting of other embodiments of the disclosed light fitting to a panel:iU follow a similar process.

It will be appreciated that although embodiments of the present invention have been described with reference to a specific form of light fitting, embodiments of the present invention include other forms of light fitting.

Although the use of rivets has been described above, it will be appreciated that other suitable attachment arrangements may be used instead.

Furthermore, embodiments of the present invention have been described herein with reference to light fittings. However, it will be appreciated that aspects of the described embodiments are not limited in application to light fittings but could be used with other electrical fittings (such as sensors including passive infra-red sensors). Lamps and sensors are, therefore, examples of electrical units.

Accordingly, an embodiment of the present invention comprises an electrical fitting which is generally as described above, however, instead of a lamp 9 and lamp socket 21 another electrical unit is fitted to the fitting (and the fitting is configured to receive the unit). For example, a passive infra-red sensor may be fitted to the fitting (and the fitting may be configured to receive the passive infra-red sensor).

An embodiment of the present invention comprises an electrical fitting with at least one ventilation aperture defined by an injection moulded intumescer material such that, in the event of a fire, the transmission of fire through t ventilation aperture is hindered.

An embodiment of the present invention comprises an electrical fitting with least one ventilation aperture defined by a substantially self-supporting and/or rigid intumescent material such that, in the event of a fire, the transmission of fire through the ventilation aperture is hindered.

In an embodiment, the electrical fitting is an electrical fitting for use in a building. In an embodiment, the electrical fitting is an electrical fitting is a domestic electrical fitting. In an embodiment, the electrical fitting is a sensor unit. In an embodiment, the electrical fitting is configured to be in electrical communication with the mains electricity supply. In an embodiment, the electrical fitting is configured to be fitted to a panel (such as a plasterboard panel). In an embodiment the electrical fitting is configured to be fitted to a ceiling or wall of a building.

New building regulations are encouraging or requiring the use of more energy efficient light fittings in many countries. In many instances manufacturers have produced energy efficient lamps 101 which use the same or a similar lamp connector 102 to conventional lamps (e.g. lamp 103) which may not be energy efficient lamps -see figures 8a-8d.

Thus, a lamp fitting which is intended to receive an energy efficient lamp (such as lamp 101) -in other words a first class of lamp -can be retrofitted with a non-energy efficient lamp (such as lamp 103) -in other words a second class of lamp -which has the same or a similar lamp connector 102.

Thus, a non-energy efficient lamp 103 can be fitted to a lamp fitting which is intended to receive an energy efficient lamp 101. This is not only contrary to the intention of providing a lamp fitting suitable for use with an energ efficient lamps but can also be dangerous if the design of the energy efficier't lamp fitting is not compatible with the use of non-energy efficient lamps (e.

the lamp fitting is not adapted to handle the higher operating temperatures which are normally associated with non-energy efficient lamps).

To this end, there is a need for a lamp socket 104 for use in a lamp fitting which is adapted to receive a lamp with a conventional lamp connector 102 but to which only a first class of lamps and not a second class of lamps can be connected.

To this end, embodiments of the present invention seek to ameliorate this problem.

An embodiment of the present invention is shown in figures 8a-d. This embodiment comprises a lamp socket 104 for a first class (or type) of lamp (e.g. lamp 101).

The lamp socket 104 comprises a main body 105 which houses a lamp connector socket 108 which is typically a lamp connector socket of a conventional type (e.g. a GUi 0 lamp connector). A ring 106 is supported with respect to the main body 105 by one or more arms 107. The ring 106 is oriented such that a major plane of the ring 106 is parallel with a major plane of the main body 105 and a central axis of the ring 106 is substantially aligned with a central axis of main body 105.

An internal diameter of the ring 106 and the distance between the ring 16 and the lamp connector socket 108 is such that a lamp of a first class of lamp can be received by the ring 106 and a lamp connector 102 of a lamp of the first class of lamp can secured to the lamp connector socket 108 housed in the main body 105 of the lamp socket 104.

The internal diameter of the ring 106 is, however, sized such that it will:ul.

against a portion of a lamp of a second class of lamp and the distance between the ring 106 and the lamp connector socket 108 is such that he lamp connector 102 of the lamp of the second class of lamp will be spaced apart from the lamp connector socket 108 when the lamp of the second class of lamp abuts against the ring 106 (as shown in figure 8d). Thus, the lamp of the second class of lamp cannot be used with the lamp socket 104.

Preferably, a plurality of arms 107 are provided such that the distance between any two adjacent arms 107 is less than the diameter of a lamp of the second class of lamp.

In an embodiment, a first section 107a of each of the plurality of arms 107 extends away from the main body 105 in a direction which is substantially perpendicular to the major plane of the main body 105 by a first distance. A second section 1 07b of each of the plurality of arms 107 extends from the respective first section 1 07a of each arm 107 in a direction which is away from the central longitudinalaxis of the main body. The first section 107a pf each arm 107 has a first length. In this embodiment, the ring 106 may notbe provided. Instead, the first length and the distance between each of the plurality of arms 107 may be such that a lamp of the second class of lamp will abut against the second sections 107b of the arms 107 and the lamp connector 102 will be spaced apart from the lamp connector socket 108.

The part of the lamp socket 104 which abuts against a lamp of the second class of lamp to prevent that lamp from being connected to the lamp connector socket 108 is an abutment arrangement.

The lamp socket 104 is preferably an integrally formed unit (with th" exception of the lamp connector socket 108) and is preferably injectk moulded.

A maximum diameter of the lamps of the first class of lamps may b substantially the same as a maximum diameter of the lamps of the secon class of lamps. The lamps of the first and second class have substantially the same form of lamp connector 102 such that a lamp of the first class and a lamp of the second class can alternately be connected to the same lamp connector socket 108.

The lamp socket 104 is for use in a lamp fitting and is preferably configured to fit within a lamp fifing. The lamp socket 104 includes electrical connections for a lamp in the lamp connector socket 108.

The lamp socket 104 preferably includes an attachment arrangement for attachment to a lamp fifing.

It will be appreciated that the lamp socket 104 could be used with one of the above described lamp fittings 1.

It will be appreciated that aspects of embodiments of the present invention as described herein may be combined and interchanged to form other embodiments of the invention.

When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the * presence of other features, .steps or components.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in dverse forms thereof.

Claims

Claims: 1. An electrical fitting adapted to be fitted to a panel, comprising: a tubular can with first and second opposing ends, the tubular can being adapted to receive at least part of an electrical unit through an opening at the first end; and an end cap secured to cover an opening at the second end of the tubular can, wherein the end cap defines one or more elongate ventilation slots and is formed from an intumescent material such that the end cap inhibits the transmission of fire through the light fitting through the or each ventilation aperture.
2. A fitting according to claim 1, wherein the end cap is substantially seif-supporting and/or rigid.
3. A fitting according to claim 1 or 2, wherein the end cap is at least partially received by the tubular can.
4. A fitting according to claim 1 or 2, wherein the tubular can is at least partially received by the end cap.
5. A fitting according to claim 4, further comprising an annular cuff fitted around the end cap.
6. A fitting according to any preceding claim, wherein the intumescent material comprises a thermoplastic mixed with an intumescent powder.
7. A fitting according to claim 6, wherein the thermoplastic is PVC, ABS, or polyethylene.
8. A fitting according to any preceding claim, further comprising a face ring or gasket attached to the first end of the tubular can to provide a thermal break between an extreme end of the light fitting and the tubular can.
9. A fitting according to any preceding claim, wherein the end cap comprises an end wall and a perimeter wall which extends from a perimeter of the end wall.
10. A fitting according to claim 9, wherein the end cap is substantially cup shaped.
11. A fitting according to any preceding claim, wherein the end cap s attached to the tubular can by a press-fitting arrangement. :*
12. A fitting according to any preceding claim, further comprising a mounting sleeve which is separated from the can by an air gap and a gasket
13. A fitting according to any preceding claim, adapted as a light fitting and configured to receive a lamp.
14. A fitting according to any of claims 1 to 12, adapted as a sensor and configured to receive a sensor.
15. A fitting according to claim 14, wherein the sensor is a passive infra-red sensor.
16. A fitting according to claim 1, wherein the tubular can includes an end cover and the end cap is secured to cover an aperture though the end cover.
17. A fitting according to any preceding claim, wherein the one or more ventilation slots are substantially radial ventilatiOn slots.
18. A method of constructing an electrical fitting comprising: providing a tubular can with first and second opposing ends and adapted to receive at least part of an electrical unit through an opening at the first end; providing an end cap; and securing the end cap to cover an opening at the second end of the tubular can, wherein the end cap defines one or more elongate ventilation slots and is formed from an intumescent material such that the end cap inhibits the transmission of fire through the light fitting through the or each ventilation aperture.
19. A method according to claim 18, wherein providing an end Cä comprises providing an end cap which is substantially self-supporting and/or rigid.
20. A method according to claim 18 or 19, wherein securing the end cap to cover the opening at the second end of the tubular can comprises at least partially receiving the end cap in the tubular can.
21. A method according to claim 18 or 19, wherein securing the end cap to cover the opening at the second end of the tubular can comprises at least partially receiving the tubular can in the end cap.
22. A method according to claim 21, further comprising providing an annular cuff fitted around the end cap.
23. A method according to any of claims 18 to 22, wherein providing an end cap comprises providing an end cap constructed out of an intumescent material which comprises a thermoplastic mixed with an intumescent powder.
24. A method according to claim 23, wherein providing an end cap comprises providing an end cap constructed out of an intumescent material which comprises PVC, ABS, or polyethylene mixed with an intumescent powder.
25. A method of any of claims 18 to 24, further comprising providing a face ring or gasket, attaching the face ring or gasket to the first end of the tubular can to provide a thermal break between an extreme end of the light fitting and the tubular can.
26. A method according to any of claims 18 to 25, wherein providing end cap comprises providing end cap which comprises an end wall and, perimeter wall which extends from a perimeter of the end wall.
27. A method according to claim 26, wherein providing an end ci *.comprises providing an end cap which is substantially cup shaped.
28. A method according to any of claims 18 to 27, wherein securing the end cap to the tubular can comprises press-fitting the end cap onto the tubular can.
29. A method according to any of claims 18 to 28, further comprising providing a mounting sleeve which is separated from the can by an air gap and a gasket.
30. A method according to any of claims 18 to 28, wherein the fitting is adapted as a light fitting and configured to receive a lamp.
31. A method according to any of claims 18 to 29, wherein the fitting is adapted as a sensor and configured to receive a sensor.
32. A method according to claim 31, wherein the sensor is a passive infra-red sensor.
33. A method according to claim 18, wherein providing a tubular can comprises providing a can including an end cover and the end cap is secured to cover an aperture though the end cover.
34. A method according to any of claims 18 to 33, wherein providing an end cap comprises providing an end cap with one or more ventilation which are substantially radial ventilation slots.
35. A kit of parts for the construction of a fitting according to claim 1, wherein the kit includes: a tubular can with first and second opposing ends, the tubular an being adapted to receive at least part of an electrical unit through an opening at the first end; and an end cap configured to be secured to cover an opening at the second end of the tubular can, wherein the end cap defines one or more elongate ventilation slots and is formed from an intumescent material such that, when secured to the tubular can, the end cap inhibits the transmission of fire through the light fitting through the or each ventilation aperture.
36. A cap for an electrical fitting wherein the cap defines one or more ventilation apertures and is constructed out of an intumescent material which comprises an intumescent powder mixed with PVC, ABS, or polyethylene.
37. A cap according to claim 36, wherein one or more of the one or more ventilation slots comprises a substantially radial slot.
38. An electrical fitting comprising: a main body including an intumescent material portion which defines at least one elongate ventilation slot, wherein the intumescent material portion is injection moulded intumescent material, and the transmission of fire through the at least one ventilation slot is hindered by the intumescent material.
39. An electrical fitting comprising a main body including at least one elongate ventilation slot defined by a substantially self-supporting and/or rigid intumescent material such that, in the event of a fire, the transmission of fire through the ventilation slot is hindered.
40. A lamp socket for use with a lamp fitting, the lamp socket comprisir, a main body; a lamp connector socket housed in the main body; and an abutment arrangement secured to and spaced apart from the ri: ;n -..body such that a lamp of a first type can be connected to the lamp connector, and a lamp of a second type abuts against the abutment member and is spaced apart from the lamp connector, wherein the first and second type of lamp have substantially the same form of lamp connector.
41. A lamp socket according to claim 40, wherein the main body and abutment arrangement are integrally formed.
42. A lamp socket according to claim 40 or 41 and a fitting according to claim 13.
43. A method according to claim 30, further comprising the step of fitting a lamp socket according to claim 40 or 41 to the light fitting.
44. An electrical fitting for attachment to a panel, the fitting comprising: a can configured to receive an electrical device; a mounting sleeve attached to the can such that the can is at least partially received by the mounting sleeve, a main wall of the can being substantially spaced apart from a main wall of the mounting sleeve, wherein the mounting sleeve is configured to be mounted to an aperture in a panel and, in combination with the can, is adapted to cover the aperture in the panel for restricting the transmission of fire through the aperture.
45. A fitting according to claim 44, wherein the main wall of the can and the main wall of the mounting sleeve are substantially concentric,
46. A fitting according to claim 44 or 45, wherein the main wall of mounting sleeve extends along part of a length of the main wall of the can.
47. A fitting according to any of claims 44 to 46, wherein the mountir sleeve and can are in connected to each other at one end thereof.
48. A fitting according to. any of claims 44 to 47, wherein an attachment arrangement is provided on the mounting sleeve, the attachment arrangement being configured to secure, at least partially, the fitting to the panel.
49. A cap for an electrical fitting wherein the cap defines one or more substantially elongate ventilation slots and is constructed out of an intumescent material.
50. A cap according to claim 49, wherein the intumescent material is a polymer based material.
51. A cap according to claim 50, wherein the intumescent material comprises an intumescent powder mixed with a polymer.
52. An electrical fitting substantially as hereinbefore described with reference to the accompanying figures.
53. A kit of parts substantially as hereinbefore described with reference to the accompanying figures.
54. A method substantially as hereinbefore described.with reference to the accompanying figures..
55. A cap for an electrical fitting substantially as hereinbefore dehed with reference to the accompanying figures.
56. A lamp socket substantially as hereinbefore described with refc ence to the accompanying figures.
57. Any novel feature or combination of features disclosed herein.