AU678037B2 - Light fitting - Google Patents

Description

P/00/01Il Regulation 3.2

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

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MANFATURNG

Acua Inetrs: PtrAtoyDlmr rs fo*evc:*L IA A RI,28Hg tet e, 11 itra utai Ineto le "LGTFTIG Th folwnttmn safl ecito fti netoicuigtebs ehdo perTOin Bt COMPETE BY APPLCAN 2V0MMMP9O.CS,1 FIELD OF THE INVENTION This invention relates to light fittings and particularly but not necessarily exclusively to light fittings of the type which comprise a lamp assembly which may be inserted into a recess or aperture in a ceiling, wall or the like so that the fitting is flush with the surface thereof. Such fittings comprise lamp assemblies which are often capable of being swivelled so as to point in various directions. These fittings are known as 'eye-ball' fittings and will be so referred to herein. Such fittings generally but not necessarily always comprise a lamp holder having a substantially spherical outer surface which is seated in a mounting so that it can be swivelled to direct the beam of the light in a desired direction.

BACKG.OUND OF THE INVENTION Modern dwellings, office buildings and other constructions commonly comprise plasterboard ceilings and walls. Plasterboard is a term used to describe usually flat and rigid sheets made substantially of plaster. However the present invention can be used with any other suitable types of sheet material used in construction such as wood, fibreboard, metals, and plastics. Furthermore, in its broader aspects, the invention could also be used with ceilings, walls etc made up of solid slabs of, for example, concrete, brickwork etc.

It is often convenient to set light fittings into a ceiling, mounting them in apertures cut into the ceiling. This enables the fittings to be mounted flush with the ceiling so that they do not obstruct the surface thereof and any heat generated by the lamps may be dissipated in the roof space above the ceiling.

It will be understood that such a fitting must in practice be designed so that it can be installed and subsequently periodically removed (for maintenance purposes, for example) from below since in most circumstances the operator has no access to the space behind the ceiling. This has in the past proved somewhat difficult and has had the results that such fittings are difficult to remove after installation and that they are not seated as securely as might be desired.

In this specification the term 'ceiling' will be used to refer to any part of a building 6919AUCS.941AwJiv t..

-3which has a surface into which a light fitting is set. The term can thus include, in particular, an overhead ceiling, a wall and also a floor.

SUMMARY OF THE INVENTION According to one aspect of the invention there is provided a light fitting comprising a first mounting member, a holder for a lamp, the holder being provided with an outer surface at least a portion of which is substantially spherical and being operably mounted on the first mounting member by swivellably seating the spherical surface in a seat formation in the first mounting member and a second mounting member which can be set into a ceiling and in or on which the first mounting member can be seated so that the first mounting member can be demounted from a working position in the second mounting member while the second mounting member remains in the ceiling.

In one aspect of the invention at least one of the mounting members comprises a substantially annular portion and the other of the mounting members comprises guide means which cooperate with the annular portion to assist in the location of the first mounting member in the working position. An advantage of the provision of the annular portion is that the working position can be selected by rotating the first mounting member about the axis of the annular portion.

In one form of the invention the annular portion is a sleeve-like portion of the second mounting member and the guide means comprises a second substantially annular 25 portion which is incorporated in the first mounting member and which is insertable in the sleeve-like annular portion of the second mounting member.

In one form of the invention the first mounting member is seated in the working position in the second mounting member by means of a clip arrangement, Advantageously one of the annular portions comprises a substantially annular seat and the other annular portion comprises clip means which can clip into the annular seat at substantially any position therearound so as to enable the first second mounting member to be mounted in the working position.

In one aspect of the invention the annular seat is formed in the first mounting member.

In one form of the invention at least one of the mounting members comprises a metal pressing. The clip means advantageously comprises one or more protuberances formed in one of the mounting members, the annular seat comprising an annular ridge which is formed in the other mounting member and over which ridge the protuberances ride and behind which the protuberances lodge when the first mounting member is being mounted in the working position.

According to one aspect of the invention, the fitting is arranged to be mounted in an aperture in a ceiling board, the fitting comprising retaining means for retaining the second mounting member in the aperture, the retaining means comprising two spaced retaining members which are pivotably mounted on the second mounting momber so that they can pass through the aperture when the second mounting member is being inserted in the aperture so that they can pivot so as to engage a rear face of the ceiling board and prevent withdrawal of the second mounting member from the aperture.

In one form of the invention biasing means is provided for urging at least one of the retaining members into engagement with the rear face of the ceiling board, According to one aspect of the invention, the biasing means comprises a spring which is 25 seated between the retaining member and a part of the second mounting member, the fitting being arranged to allow a tool to be inserted through the aperture to seat and unseat the spring from the retaining member and/or said part of the second mounting member.

30 BRIEF DESCRIPTION OFTHE DRAWINGS s Various aspects of the invention are described by way of example with reference to the accompanying drawings in which Figure 1 is a cross sectional elevation of an 'eyeball' type light fitting assembly; 6919AUCSt94JW/iVa

I

Figure 2 is a cross sectional elevation of an outer ring being part of the assembly shown in Figure 1; Figure 3 is a plan view of part of the outer ring; Figure 4 is a cross sectional elevation of an inner ring also being part of the assembly shown in Figure 1; Figure 5 is a view on Arrow A in Figure 1, showing an arrangement for retaining the outer ring in place; Figure 6 is an elevation of a shoe for mounting a shade on the inner ring; and Figure 7 is a view, similar to Figure 5, of a modified arrangement for retaining the outer ring in place.

DESCRIPTION OF EMBODIMENTS SHOWN IN THE DRAWINGS Referring first to Figures 1 to 6 of the drawings there is shown a light fitting assembly 10 which is intended to be mounted in an aperture cut in a ceiling 12 or the like. The assembly 10 comprises a lamp holding assembly including a shade 14 carrying a socket 16 for receiving a lamp 18; a first mounting member in the form of an inner ring 20 on which the lamp holding assembly is mounted; and a second mounting member in the 25 form of an outer ring 22 on which the inner ring is mounted.

The socket 16 and the lamp 18 are conventional, commercially available components and need not be described in detail. The socket includes terminals to which electrically conductive wires or cables are connected for supplying electric power to the lamp.

In the present case the shade 14 is of sheet metal spun to form a spherical shape. By virtue of this shape the shade, when mounted, as will be described, in the inner ring can be swivelled in two orthogonal directions so that the beam from the lamp can be directed where desired. This is a well known characteristic of 'eyeball' fittings and need not be described in detail here.

691AUcs,.94/lW/Vi -6- The inner ring 20 is an annulus which is also spun from sheet metal. It comprises a cylindrical skirt 24 with a wide flange 26 projecting radially outwardly from the outer end thereof and a narrow lip 28 projecting radially inwardly from the inner end thereof.

A protuberance in the form of an annular ridge 30 is formed in the skirt 24 at a position approximately one third of the distance from the flange 26 to the lip 28. The annular ridge projects outwardly from the centre of the inner ring The shade is mounted in the inner ring 20 by means of a pair of substantially identical shoes 32 which are mouldings of a low friction plastics material. Each shoe comprises a generally flat, rectangular body 34 having along its upper edge a lip 38 which, in use, projects away from the centre of the fitting. The lip 38 incorporates a recess 40 which receives the lip 28 of the inner ring. The body 34 has a second lip 42 along its lower edge. This lip also projects, in use, away from the centre of the fitting and bears on the inner face of the skirt 24. A spigot 44 is formed at the centre of the body. The spigot projects through a hole 46 in the shade towards the centre of the fitting, There are thus two holes 46 in the shade. They are located diametrically opposite one another on a line which is perpendicular to the axis X of the lamp.

The shoes are flexible so that, when fitted in the narrow space between the shade and the inner ring, they can take up the curvature thereof. By virtue of the engagement of the lip 28 in the recess 40, the shoes are retained on the inner ring. The shade can pivot about the spigots 44 and rotate in the inner ring about the central axis thereof, the shoes sliding along the lip 28 in the process. Due to the location of the holes 46 on a diameter 25 of the shade and the spherical shape of the shade, the clearance between the shade and the inner ring remains constant.

The outer ring 22 comprises a cylindrical skirt 48 with a flange 50 projecting radially outwardly from the outer end thereof. The sizes of the skirts 24, 48 of the two rings are selected so that the skirt 24 can fit comfortably into the skirt 48 with a small clearance between the inner face 49 of the skirt 48 and the outer limit of the annular ridge There are however three protuberances or dimples 52 formed in the skirt 48, located at equal angular distances apart about the skirt. These dimples project inwardly so that, when the skirt 22 is inserted into the skirt 48 the annular ridge 30 engages the dimples, The skirt 48 is sufficiently elastic to yield and thus enable the annular ridge to ride over the dimples which snap back into place behind the annular ridge once it has passed. The 6919AVCs.s4/0ILV dimples are positioned so that the annular ridge has just passed them when the flange 26 of the inner ring comes up against the flange 50 of the outer ring. The inner ring can thus be clipped into and out of its working position in the outer ring by this arrangement.

The outer ring is provided with two diametrically opposed lugs 54 spot welded to the skirt 48 and projecting away from the flange 50. Each lug has a central aperture 56 which is spanned by a split pin 58 mounted in eyes 60 defined by straps 61 pressed out of the body of the lug on either side of the aperture. A toggle 62 is pivotably mounted on each split pin. A spring 64 is mounted over each split pin and urges the toggle to pivot downwardly on the split pin. To mount the outer ring in the ceiling 12, the toggles are pivoted against the action of the springs 64 until they both project vertically upwardly as shown in dotted outline at 66 in Figure 1. They are held in this position while the outer ring is inserted, toggles and skirt first, through the aperture in the ceiling. When the toggles are released they bear down on the upper surface of the ceiling, drawing the flange 50 snugly against the lower surface of the ceiling, Thereafter the wires or cables for providing power to the fitting are pulled through the aperture and the outer ring 22 connected to the terminals of the socket 16 after the latter has been "Ss 20 mounted on the shade and making sure that the shade has already been mounted on the inner ring. Once the connections are made the whole inner ring assembly, comprising the shade, socket and inner ring, is clipped into the outer ring.

This convenient method of mounting and demounting the lamp mounting from the ceiling Is a substantial advantage of the invention.

The spring 64 which provides the pressure on each of the toggles is, in the example shown, a helical compression spring wound around the pin 58 with one straight end pressing against the toggle 62 and the other straight end 72 pressing against a cross-piece 74 of the lug 54 spanning the aperture 56. In the example shown in Figure 7, this construction is modified. Here, the cross-piece 74' of the lug 54' is provided with a short cut-out 76 and a long cut-out 78. The short cut-out acts as a seat to hold the end 72' of the spring 64' in position on the cross-piece The long cut-out 78 is long enough so that the straight end 72' of the spring 64' is able to pass therethrough. This can be achieved by inserting a probe such as a screw driver or the like through the aperture in the ceiling and through the aperture 56' in the lug, the end 72' being lifted 6919AUCS.,414W/Niv -8against the action of the spring out of its seat on the cross-piece and into alignment with the long cut-out. This releases the toggle from the spring action and it is able to pivot freely to, and remain in, the vertical position 66 for facilitating insertion and removal of the outer ring 22 into and out of the aperture in the ceiling.

It is not intended that the scope of a patent granted in pursuance of the application of which this specification forms a part should exclude modifications and/or improvements to any matter described and/or illustrated herein which are within the scope of the invention or be limited by such matter further than is necessary to distinguish the invention from the prior art.

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