GB2528391A

GB2528391A - Electrical connection system and method of installation

Info

Publication number: GB2528391A
Application number: GB1512175.9A
Authority: GB
Inventors: Robert Edward Jordan
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-07-14
Filing date: 2015-07-13
Publication date: 2016-01-20
Anticipated expiration: 2035-07-13
Also published as: GB201512175D0; WO2016009181A1; GB201412489D0; GB2528391B

Abstract

An electrical connection system for detachably connecting an electrical device 101 to electrical supply cables, comprises a plug 40 electrically connectable to the device and a socket 24 electrically connectable to the cables. The socket provides a mounting and an electrical connection with the plug via corresponding contacts. The mounting connection is releasable and allows the plug to be rotatable in said socket. The contacts of the socket and the plug are arranged so that when the plug is mounted in the socket they are electrically connected with one another in any orientation of the plug in the socket, for example the plug may have annular contacts. The mounting connection between the plug and socket comprises locating pins around an outer periphery of a plug housing configured to engage with an open end of pin locating slots in the socket leading to a mounting channel. The locating pins are rotatable around the channel. The connectors may be used to mount a light fitting to a ceiling.

Description

ELECrRICAL CONNECTION SYSTEM AND METHOD OF INSTALLATION

Field of the Invention

The invention relates to an electrical connection system for detachably connecting and mounting an electrical device to electrical cables. The invention also relates to a method of installing an electrical connection system enabling releasable connection of an electrical device to electrical cables.

Background to the Invention

Installing or changing an electrical device, such as a light fitting, can be a difficult task. For example, some consumers employ the services of an electrician each time they need to install a new electrical device, which can be costly. Other consumers attempt to install the electrical device themselves, which may be a dangerous task. Without the correct training this can also create problems that are expensive to rectify.

Installing or removing, for example, a ceiling mounted or wall mounted electrical device, is usuallya two-person task; one person holds the electrical device while the other connects or disconnects the circuitry. Where only one person is available, instead a first connector cable is sometimes used to hold the weight of the electrical device causing strain on the cable.

When loop in and loop out supply cables with switch wires are used to supply electricity to an electrical device, there is a recommended procedure for connecting an electrical device. This procedure involves removing the floor boards from above the ceiling to access the ceiling void. The supply cables are then pulled back into the ceiling void and connected into a joint box. A single supply cable is taken from the joint box and pushed through the ceiling to supply the new electrical device. This process can be difficult as the floor boards may be inaccessible or require cutting. Due to the difficulties of accessing the area abovethe ceiling, a common method of connecting lighting is to use connector blocks, but these present problems due to exposed conductors and limited space, which can cause cable to become loose an object of the present invention to address these issues.

Summary of the Invention

According to one aspect of the invention there is provided an electrical connection system for detachably connecting an electrical device to electrical supply cables, comprising: a plug being electrically connectable to an electrical device, a socket being electrically connectable to electrical power supply cables, said socket being adapted to provide a mounting connection with said plug and an electrical connection with said plug via corresponding contacts, wherein the mounting connection is releasable and further allows the plug to be rotatable in said socket, and the corresponding contacts of the socket and the plug are arranged so that when the plug is mounted in the socket the contacts are electrically connected with one another in any rotation of the plug in the socket, wherein the plug comprises a housing comprising the plug contacts and corresponding electrical terminals, characterised in that the mounting connection between the plug and socket comprise cooperating parts in the form of locating pins around an outer periphery of the housing configured to engage with an open end of pin locating slots in the socket leading to a mounting channel and the locating pins are rotatable around the channel.

Preferably, the contacts in the socket are arranged across a diameter of the socket at predetermined distances from one another. Preferably, each of the contacts of the plug are arranged concentrically within the plug and at a diameter position corresponding to the predetermined distances of the contacts in the socket. Preferably, the concentric contacts of the plug comprise a central pin surrounded by coaxial rings.

Preferably, a live contact is substantially centralised in the socket. Preferably, a socket neutral contact and a socket switch live contact are diametrically opposed on opposite sides of the live contact. Preferably, the socket neutral contact and the socket switch live contact are disposed at different distances from the live contact.

Preferably, the socket neutral contact is closer to the live contact than the switch live contact is to the live contact. Preferably, a socket earth contact is disposed outwardly of the switch live and neutral contacts.

Preferably, the plug live contact is in the form of a centralised pin and the plug neutral, earth and switch live contacts are in the form of coaxial rings. Preferably, the plug coaxial rings depend outwardly from the live pin in the order of neutral, switch live and then earth. However, any other contact arrangement across the diameter of the socket and the plug may be provided.

Preferably, at least one insulation ring is provided between the plug contacts and at least one insulation ring is provided between the socket contacts. Preferably, the socket comprises an insulation ring to insulate the live contact from the neutral and switch live contacts. Preferably, the socket comprises an insulation ring to insulate the neutral and switch live contacts from the earth contact. Preferably, the plug comprises an insulation ring to insulate the neutral contact from the switch live contact. Preferably, the plug earth contact is distanced from the plug switch live contact.

Preferably, the system further comprises a support means for location in an aperture of a mounting structure.

Preferably, the support means comprises a mounting means for mounting the support means substantially behind the mounting structure. Preferably, the mounting means comprises a retractable bearing means for bearing against a surface behind the mounting structure. Preferably, the mounting means also comprises a flange to abut the mounting structure and retain the support means in the aperture, Preferably, the support means comprises a retention means for the socket. Preferably, the retention means is provided at, or close to a first open end of the support means. Preferably, the retention means comprises a retaining lip for engagement with locking bars on the socket. Preferably, the locking bars are rotatable over the retaining lip and the retention means comprises a securing means to stop further rotation. Preferably, in order to aid releasable mounting, the lip comprises openings for passage of the locking bars in specific locations, although it will be appreciated that resiliently flexible components may be used additionally or alternative to effect the releasable mounting.

Preferably, the socket provides electrical terminals connected to the socket contacts. Preferably, the socket terminals are connected to electrical supply cables after passing through apertures in a support means housing and a socket housing. Preferably) the socket sits substantially wholly within the support means, e.g. substantially behind the mounting structure.

Preferably, the socket comprises an upper housing that is substantially separated from a lower housing, the lower housing being open at a lower end and comprising the socket contacts. Preferably, the upper housing is substantially closed and comprises the electrical terminals for connection to the electrical supply cables.

Preferably, the plug comprises a housing comprising the plug contacts and corresponding electrical terminals.

Preferably, the plug comprises a mount integrally formed with the housing and comprising a weight bearing flange or plate. Preferably, the housing is further split into upper and lower sub-housings. Preferably, the upper sub-housing is open at a first end comprises the plug contacts. Preferably, the lower sub-housing is essentially closed off and provides the plug electrical terminals which correspond to the plug contacts. Preferably, cables corresponding to the plug electrical terminal exit the lower housing and are connected to one or more universal electrical connection means (e.g. that can be used to connect any standard electrical device). Preferably, the universal electrical connection means comprises one or more electrical chip blocks.

Preferably, the mounting connection between the plug and socket comprises cooperating parts. Preferably, the cooperating ports comprise on arrangement that allows for a simple one-step insert (the plug into the socket) and rotate (the plug in the socket) mechanism. Preferably therefore, the plug housing comprises locating pins around an outer periphery configured to engage with an open end of pin locating slots in the socket leading to a mounting channel. Preferably, the locating pins are rotatable around the channel. Preferably, the mounting connection comprises a rotation resistance means in the form of teeth on the plug for enragement with a notch in the socket. Preferably, the mounting connection comprises at least two, most preferably three locating pins as described, which provides a very secure and weight-bearing mounting connection.

Preferably, the locating pins comprise further electrical contacts allowing for additional control signals. The additional control signals may be in the form of control of further electrical equipment for intelligent automatic control, of electrical devices. Preferably, terminal connections for the locating pins are located within the plug housing.

Preferably, the mounting connection comprises a safety drop system. Preferably, the safety drop system is formed as part of the pin locating slots. Preferably, the the pin locating slots in the socket comprise an overhang extending from one side of the slots at the open end. Preferably, the pin locating slots in the socket comprise an outwardly tapered portion to widen the open end that would be otherwise closed by the overhang.

Preferably, the system comprises an adjustable suspension bracket for connecting the plug to an electrical device. Preferably, the bracket comprises a rectangular suspension plate for engagement with the slot above the plate of the plug. Preferably, the bracket comprises at least one form of mounting to an electrical device.

According to a second aspect of the invention there is provided a socket for an electrical connection system for detachably connecting an electrical device to electrica power supply cables behind a mounting structure, the system comprising support means for location substantially behind the mounting structure, said support means comprising the socket, the socket being electrically connected to power cables, and the socket being arranged to receive a plug for electrical connection to the electrical device, said socket being adapted to provide a mounting connection with said plug and an electrica connection with said plug via corresponding contacts, wherein the mounting connection is releasable and further allows the plug to be rotatable in said socket, and the corresponding contacts of the socket arranged so that when the plug is mounted in the socket, the socket contacts are electrically connected with the plug contacts in any rotation of the plug in the socket, characterised in that the mounting connection provided by the socket comprises cooperating parts in the form of open-ended pin locating slots leading to a mounting channel adapted to engage with plug locating pins for rotation around the channel.

It is to be appreciated that features of the socket described in connection with the first aspect of the invention also apply to the second aspect of the invention.

According to a third aspect of the invention there is provided a plug for an electrical connection system for detachably connecting an electrical device to electrical power supply cables in a mounting structure, the system comprising a socket for receiving the plug, wherein said socket is connectable to electrical power supply cables; said plug being adapted to have a mounting connection with said socket and an electrical connection with said socket via corresponding contacts, wherein the plug is electrically connectable to an electrical device, wherein the mounting connection is releasable and further allows the plug to be rotatable in said socket, and the corresponding contacts of the plug are arranged so that when the plug is mounted in the socket, the plug contacts are electrically connected with the socket contacts in any rotation of the plug in the socket, wherein the plug comprises a housing comprising the plug contacts and corresponding electrical terminals,

S

characterised in that the plug comprises cooperating parts for the mounting connection in the form of locating pins around an outer periphery of the housing configured to engage with an open end of pin locating slots in the socket leading to a mounting channel such that the locating pins are rotatable around the channel.

It is to be appreciated that features of the plug described in connection with the first aspect of the invention also apply to the third aspect of the invention.

According to a fourth aspect of the invention there is provided a method of installation of an electrical connection system, comprising: mounting a support structure in a mounting structure and passing electrical supply cables into a housing of the support structure; mounting a socket in the support structure comprising open-ended of pin locating slots in the socket leading to a mounting channel, and electrically connecting the cables to terminals housed within the socket to supply power to socket contacts also housed within the socket; providing a plug with a housing comprising electrical contacts and electrical terminals for electrical connection to an electrical dev[ce, and locating pins around an outer periphery of the plug housing; and releasably mounting the plug in the socket in any rotation to provide an electrical supply to the plug for supply to said electrical device via the plug and socket contacts, by locating said locating pins in the pin locating slots and rotating the pins around the channel.

According to a fifth aspect of the invention there is provided a bracket with any combination of features as hereinbefore described.

According to a sixth aspect of the invention there is provided a support means with any combination of features as hereinbefore described.

In any of the above embodiments, the electrical device may be a light fitting.

According to another aspect of the invention, there is provided an electrical connection system for detachably connecting an electrical device to electrical ceiling cables, comprising: support means for location substantially in a ceiling, said support means including a socket for receiving a plug; a plug for attachment to an electrical device, said plug being detachably securable in said socket via an aperture in the ceiling, wherein said socket is connectable to electrical power supply cables, wherein the plug and the socket are arranged to electrically connect said electrical device to said power supply cables when said socket is connected to the power supply cables and when said plug is secured in the socket, and wherein the electrical connection system is arranged to carry the weight of the electrical device when the support means is located substantially in the ceiling and the plug is secured in said socket.

Preferably, the support means and the plug are configured for location substantially in the ceiling, such that a planar open end of a light fitting can fit substantially flush against a lower surface of the ceiling. Preferably, the support means includes a flange for location against a lower surface of the ceiling. Preferably, said support means includes a mounting means) the mounting means including means for bearing against an upper surface in the ceiling, and the mounting means and the socket being configured so that the mounting means retains the socket.

Preferably, said bearing means is reconfigurable from a retracted position in which the support means can be inserted through the aperture in the ceiling, to an extended position in which return of the support means through the aperture is prevented. Preferably, the support means includes means for releasably preventing retraction of the bearing means.

Preferably, the mounting means includes a lip arranged to extend flush against a lower surface of the ceiling, wherein said preventing means is further arranged to clamp a portion of the ceiling between the bearing means and the lip.

Preferably, the socket and the plug are arranged to allow rotation of the plug in the socket.

Preferably, the socket includes electrical contacts and means for connecting the electrical contacts to the electrical ceiling cabling; and the plug includes means providing electrical connection from the electrical contacts of the socket to the attached electrical device. The electrical contacts may be in a radially offset arrangement, wherein the means providing electrical connection is arranged to maintain connection with the contacts on rotation of the plug in the socket.

Preferably, the system comprises means for attaching the plug to a fitting of the electrical device, wherein the fitting is configured to fit flush against the lower surface of a ceiling and the system permits the fitting to fitflush against the lower surface of the ceiling. Preferably, the means for attaching is adjustable to attach to the interiors of fittings of different sizes and/or shapes.

The support means may include intumescent material arranged to substantially close the aperture in the ceiling in the event of fire.

According to another aspect of the invention there is provided a method of installing an electrical connection system enabling releasable connection of an electrical device to electrical ceiling cables, comprising: locating in a ceiling through an aperture in the ceiling, a support means for carrying the weight of an electrical device, the support means including a socket for receiving a plug, and connecting the socket to electrical cabling in the ceiling; attaching a plug to an electrical device; securing the plug in said socket, whereby the plug and socket electrically connect the electrical ceiling cabling and the electrical device.

The method may comprise locating the support means and connecting the socket comprising locating a mounting means in the ceiling through an aperture in the ceiling, connecting the socket to the power supply cables in the ceiling and then securing the socket to the mounting means. The method may further comprise attaching the plug to a fitting of the electrical device using an adjustable suspension bracket.

In yet another aspect of the invention there is provided a plug for an electrical connection system for detachably connecting an electrical device to electrical power supply cables in a ceiling, the system comprising support means for location substantially in the ceiling, said support means including a socket for receiving the plug, wherein said socket is connectable to electrical power supply cables; wherein the plug is attachable to an electrical device, said plug being detachably securable in said socket via an aperture in the ceiling when said support means is mounted in the ceiling, wherein the plug and the socket are arranged to electrically connect said electrical device to said electrical power supply cables when said plug is secured in the socket and said socket is connected to the power supply cables, and wherein the electrical connection system is arranged to carry the weight of the electrical device.

In another aspect of the invention there is provided a socket for an electrical connection system for detachably connecting an electrical device to electrical power supply cables in a ceiling, the system comprising support means for location substantially in the ceiling, said support means including the socket and the socket being arranged to receive a plug attachable to the electrical device; wherein said socket is connectable to electrical power supply cables; wherein said socket is arranged to detachably receive the plug therein via an aperture in the ceiling when said support means is mounted in the ceiling, wherein the socket is arranged to electrically connect said plug to said electrical power supply cables when the plug is secured therein and the socket is connected to the power supply cables, and wherein the electrical connection system is arranged to carry the weight of the electrical device.

In another aspect of the invention there is provided a back box forfitting in a wall or a ceiling through an aperture in the wall, comprising: a tubular body including a first end and a second end; a planar flange extending from the periphery of the first end, wherein the aperture and the body are respectively sized such that when a second end of the tubular body is inserted through the aperture from a first side of the wall, the flange bears against a first surface on the first side; means for bearing against a second surface on a second side of the wall, the means being reconfigurable from a retracted position in which inserting of the tubular body is not impeded, to an extended position in which return of the body through the aperture is prevented; means for preventing return of the bearing means to the retracted position.

Preferably, the preventing means comprises a pawl and a ratchet configured to prevent retraction.

Preferably, the back box comprises a means for urging the bearing means against the second surface, thereby to clamp the wall between the planar flange and the bearing means. Preferably, the means for urging comprises a threaded bore fixedly attached to the bearing means, and a screw fixedly disposed relative to the tubular body, the threaded bore and the screw being arranged so that screwing of the screw into the threaded bore draws the bearing means towards the planar flange.

In the above aspects, the electrical connection system is as defined herein before.

It is to be appreciated that the aspects of the first aspect of the invention apply to the other aspects of the invention where applicable and vice versa.

Brief Description of the Figures

For better understanding of the present invention, an embodiment will now be described, by way of example only, in which: Figure 1A is an underside view of a back box for an electrical connection system in accordance with an embodiment of the invention; Figure lB is a front view of the back box of Figure 1; Figure 1C is a side view of the back box of Figure 1; Figure 1D is a perspective underside view of the back box of Figure 1; Figure lE is a close up view of the side view of Figure 1C; Figure iF is a diagram of a fixing wing of the back box of Figure 1; Figure 2A is an underside view of a socket for an electrical connection system in accordance with an embodiment of the invention; Figure 2B is a side view of the socket of Figure 2A; Figure 2C is a side cross-sectional view of the socket of Figure 2A; Figure 2D is a perspective top view of the socket of Figure 2A; Figure 3A is a perspective view of the socket of Figure 2A located in a back box of Figure 1A; Figure 3B is an exploded view of the components of an electrical connection system in use with an electrical device; Figure 3C is a view of a plug component of the electrical connection system in use with an electrical device; Figure 4A is a top view of a plug for an electrical connection system in accordance with an embodiment of the invention; Figure 4B is a side view of the plug of Figure 4A; Figure 4C is a cross-sectional side view of the plug of Figure 4A; Figure 4D is a perspective underside view of the plug of Figure 4A; Figure 4E is a perspective top view of the plug of Figure 4A; Figure SA is a side view of a bracket for an electrical connection system in accordance with an embodiment of the invention; Figure SB is a top view of the bracket of Figure SA Figure SC is a perspective underside view of an arrangement comprising the bracket of Figure SA in use with a plug of Figure 4A; Figure SD is a perspective top side view of a plug arrangement in use with a standard bracket on an electrical device; Figure LA is a perspective top side view of the bracket and plug arrangement of Figure SC in use with a light fitting; Figure LB is a perspective top side view of the bracket and plug arrangement of Figure SC in use with a different light fitting; and Figure 6C is a side diagrammatic view of an electrical connection system in use with a light fitting.

Detailed Description of Embodiments

As shown in the Figures, there is provided an electrical connection system for detachably connecting an electrical device to electrical supply cables, comprising: a plug 40 being electrically connectable to an electrical device, a socket 24 being electrically connectable to electrical power supply cables, said socket 24 being adapted to provide a mounting connection 33 with said plug 40 and an electrical connection with said plug 40 via corresponding contacts3o, 42, wherein the mounting connection 33 is releasable and further allows the plug 40 to be rotatable in said socket 24, and the corresponding contacts 30,42 of the socket 24 and the plug 40 are arranged so that when the plug 40 is mounted in the socket 24 the contacts 30, 42 are electrically connected with one another in any rotation of the plug 40 in the socket 24. The system further comprises a support means in the form of a back box 2.

The electrical connection system electrically easily connects an electrical device, for example a light fitting 101,102, to electrical cables in a mounting structure 110 void, e.g. wall or ceiling, to enable supply of power to the electrical device. A mounting structure 110 is formed of a solid wall having upper and lower surfaces and a void there behind. The easy connection is derived form the fact that the socket 24 can be fitted to the mounting structure 110 in one preparation step, the plug 40 can be fitted to the electrical device in a separate preparation step and the electrical and mounting connection of the plug 40 to the socket 24 together is achieved by a simple push and rotate action of the plug 40 in the socket 24. This means that the connection can be performed one-handed leaving the other hand free to support the electrical device if required. The electrical device need not be left dangling from a support cable, or be supported by a second person in the meantime.

As shown in Figures 2A to 2D, there is provided a socket 24 for an electrical connection system for detachably connecting an electrical device to electrical power supply cables behind a mounting structure 110, the system comprising support means for location substantially behind the mounting structure,said support means comprising the socket 24, the socket 24 being electrically connectable to power cables, and the socket 24 being arranged to receive a plug 40 for electrical connection to the electrical device, said socket 24 being adapted to provide a mounting connection 33 with said plug 40 and an electrical connection with said plug 40 via corresponding contacts 30,42, wherein the mounting connection 33 is releasable and further allows the plug 40 to be rotatable in said socket 24, and the corresponding socket contacts 30 are arranged so that when the plug is mounted in the socket 24, the socket contacts 30 are electrically connected with the plug contacts 42 in any rotation of the plug 40 in the socket 24. Again the support means comprises a back box 2.

As shown in Figures 4A to 4E, there is provided a plug 40 for an electrical connection system for detachably connecting an electrical device to electrical power supply cables in a mounting structure, the system comprising a socket 24 for receiving the plug 40, wherein said socket 24 is connectable to electrical power supply cables; said plug 40 being adapted to have a mounting connection 33 with said socket 24 and an electrical connection with said socket 24 via corresponding contacts 30, 42, wherein the plug 40 is electrically connectable to an electrical device, wherein the mounting connection 33 is releasable and further allows the plug 40 to be rotatable in said socket 24, and the corresponding plug contacts 42 are arranged so that when the plug 40 is mounted in the socket 24, the plug contacts 42 are electrically connected with the socket contacts 30 in any rotation of the plug 40 in the socket 24.

The system comprises a back box 2. Referring to Figures LA to 1D, the back box 2 has a generally cylindrical hollow body 4 having a first end 4a and second end 4b. The first end 4a comprises a series of holes 14 through which electrical supply cables can be fed. The supply cables can thus enter into the back box 2 from a number of directions. The unused holes 14 may be provided with caps to prevent unwanted dust and other items from accessing the hollow of the back box 2.

The body 4 provides two diametrically disposed apertures 9 extending in the same direction as the axis of the body 4. At a first end 9a, the apertures widen out to provide access to the hollow of the back box 2, whilst at a second end, the aperture Yb is narrower and elongate. Each of the apertures Yb are flanked by sets of teeth 7.

The body 4 also provides two diametrically disposed slots 16 extending in the same direction as the axis of the body 4. These slots 16 are provided between the apertures 9 around the circumference of the body 4 such that the apertures 9 and the slots 16 are equally spaced from one another. The slots 16 allow for screws (not shown) to be passed from the hollow of the body 4 through the slots 16 at a chosen point and screwed into a joist or other supporting structure in the void of the mounting structure 110.

The inside of first end 4a of the back box 2 has an intumescent pad 18. In the event of fire, the intumescent pad 18 expands to fill the back box 2, to thereby close the aperture in the mounting structure 110. This allows the back box 2 to comply with building regulations and enables the mounting structure 110 to have a good fire rating.

In use, the body 4 is sized to be inserted the first end 4a first through a pre-cut substantially circular aperture in a mounting structure 110. A flat flange 6 extends radially from the second end 4b of the body 4 and prevents the back box 2 from being wholly inserted into the mounting structure 110. The flange 6 is thin and preferably of thickness such that it does not interfere with fixing of an electrical device fitting such as a ceiling rose or like part of, for example, a light fitting 101, 102. In other alternative embodiments, the flange 6 may be absent, and the back box 2 may rely on the slot 16 and screw arrangement to maintain its position in the void beyond the mounting structure 110.

The back box 2 includes an inwardly extending stopper lip 26 extending circumferentially around the interior of the body 4 at the second end 4b, located at a small distance just above the flange 6, The stopper lip 26 is intermittent with gaps 26a at three equally spaced positions. Just above the lip 26, the body 4 provides an inwardly protruding flange 20. The flange is provided with a pair of holes 20a there through at diametrically disposed positions on the body 4, which correspond with a central axis of the apertures 9.

The back box 2 includes a pair of extendible fixing wings 8 disposed diametrically opposite one another on the body 4 and within the apertures 9. The fixing wings 8 are slidably movable into and out of the body 4 and are movable up and down the body 4 facilitated by aperture 9 in similar fashion to back boxes 2 provided on the market, such as plasterboard box MT MDLB6 sold by TLC (Southern) Ltd (http://www.tlc-direct.co.uk/Products/MTMDLB6.htmI). The fixing wings 8 and the body 4 are therefore, configured to bear against inside surfaces of the mounting structure 110 of different thicknesses.

Briefly, each wing 8 is provided with three wide flexible prongs Ba, with narrow channels Sb therebetween. The two outer prongs Ba' are relatively short in relation to the middle prong Ba" and have inwardly tapered ends.

Once past the outer prongs Ba', the middle prong Ba" widens and increases in depth to produce two feet 3d, which extend into the area just below the outer prongs Ba'. The feet Sd are raised above the outer prongs Ba'.

The middle prong Sa" assists in retaining the fixing wing 8 in the back box 2, whilst the outer prongs Ba' catch under the teeth 7 at either side of the aperture 9, to resist movement of the wing 8 away from its level arrangement. Each of the prongs 8, when in a retracted position, are substantially located in the hollow of the body 4 and the fixing wings 8 do not catch on the mounting structure 110 when the back box 2 is inserted into the void. Once the body 4 of the back box 2 has been inserted through the hole in the mounting structure 110, the fixing wings Scan be manually slid outwards, by pushing from inside the body 4,so as cause the wings B to protrude from the body 4, with the feet Sd acting as a stopper. Each fixing wing B is provided with a series of downwardly protruding spikes Sc for biting down onto the inside of the mounting structure 110 to prevent rotation of the back box 2 in the aperture. The fixing wings S comprise a threaded hole 20b located centrally in the middle prong Ba". When a fixing wing 8 is in an extended position, the hole 20b of a fixing wing 8 cooperates with a corresponding hole 20a on the flange 20.

Turning to Figures 2A to 2D, the socket 24 comprises a generally cylindrical hollow body 23, which is dimensioned to fit inside the back box 2. A first end 23a of the body is generally closed, whilst a second end 23b is generally open. The second end 23b of the socket body 23 has an outwardly extending planar flange 25.

The flange 25 and the stopper lip 26 of the back box 2 are respectively shaped to fit together so that when the socket 24 is inserted into the back box 2, the flange 25 abuts against the stopper lip 26 restricting the extent to which the socket 24 can extend into the back box 2. The flange 25 and the stopper lip 26 are shaped to locate the socket 24 into a desired position in the back box 24, in this case such that the axes of the socket 24 and the back box 2 are coaxial and the open end 23b of the socket 24 and the second end 4b of the back box 2 are substantially coplanar.

The socket 24 provides three locking bars 31 connected to the flange 25. The locking bars 31 are equally spaced from one another around the periphery of the flange 25 and are disposed above a cut-out 32 in the flange 25.

Each bar 31 therefore comprises an upstanding portion 31a extending from a back of the respective cut-out 32 of the flange 25 and a level portion 31b extending over the cut-out 32, so as to essentially block the cut-out 32 from the above.

The socket 24 provides a pair of screws 22 extending through diametrically opposed holes in the flange 25. The holes in the flange 25, the threaded holes 20a/ 20b of the back box 2/fixing wings S can be aligned and the socket 24 fixed to the back box 2 using the screws 22. When the socket 24 is screwed into position in the back box 2, the screws 22 pull the wings 8 towards itself to engage the spikes Sc with the mounting structure 110.

Inside the body 23, the socket 24 includes an upper housing 24a that is substantially separated from a lower housing 24b. The upper housing comprises electrical terminals 28 for connection to incoming electrical supply cables. The electrical terminals 28 are electrically connected to the socket contacts 30. Within the lower housing 24a, socket contacts 30 for electrical connection with the plug 40 are mounted, The upper housing 24a is substantially closed, whereas the lower housing 24b is open ended.

Live 30a, neutral 30b, earth 3Cc and switch live 30d contacts are provided, The contacts 30 are arranged across the same diameter line of the socket 24, with the live contact 30a being located centrally of the socket 24, the neutral contact 30b being located off-centre in one direction from the live 30a, the switch live contact 30d, being located off-centre in the opposite direction from the neutral 3Db and the earth contact 30c being disposed outwardly from the switch live 30d contact.

Socket insulating rings 36a/ 36b electrically isolate the contacts 30 from one another. The rings 36 depend from the top of the socket 24 concentrically with respect to the axis of the cylindrical body 23 of the socket 24.

The first ring 36a is located around the live contact 30a, such that the live 30a is located within the inner ring 36a to be isolated from the surrounding neutral 3Db and switch live 30d contacts on either side of that ring 36a.

The second ring 3Gb is located outside the neutral 3Db and switch live 30d contacts, such that the neutral contact 3Db and the switch live contact 30d are both located between the rings 36a and 36b. Since the neutral 3Db and switch live 30d contacts are diametrically opposite one another, the first ring 36a provides an insulation barrier between the two. The earth contact 30c is located outside the outer of the rings 3Gb, therefore, being isolated from all other socket contacts 30.

Corresponding live, neutral and earth cables enter the socket 24 through one or more of the holes 24c and connect to the terminals 28. The incoming cables are fixed in position to the terminals 28 by screws accessible through apertures 29 in the socket body 23. The socket contacts (30a-30d) are then electrically communicated with the mains supply. The permanent live 30a contact and feed provides the option to connect dimming equipment, emergency lighting or access to Ethernet over power via the electrical device.

As can be seen in Figures 3A and 3B, the back box 2 is located in a mounting structure 110 as previously described.

Before the socket 24 is located in the back box 2, the cables entering the back box 2 are connected to the terminals 28 of the socket through the holes 24c and secured by screws through holes 29. The socket 24 is now supplied by mains power.

The socket 24 can be located in the back box 2, such that the socket 24 does not, or substantially does not, extend below the lower surface of the mounting structure 110. The locking bars 31 of the socket 24 are aligned with the gaps 26a in the stopper lip 26 and the socket 24 is then pushed upwardly so the bars 31 pass beyond the lip 26. The socket 24 is then twisted so that the bars 31 pass beyond the gaps 26a over the stopper lip 26. In doing this, the flange 25 of the socket 24 abuts the stopper lip 26 to stop it from passing too far into the hollow body 4 of the back box 2 and the flange 25 sits inside and flush with the flange S of the back box 2.

A small aligning adjustment may be required and then the screws 22 of the socket can be screwed through the holes 20a of the inwardly protruding flange 20 and then into the holes 20a of the fixing wings 8, to further secure the socket 24, but also to pull the spikes 7 of the fixing wings 8 into biting engagement with the inside of the mounting structure 110. The socket 24 and the back box 2 are now securely mounted in the void of the mountable surface 110, with no rotational movement.

Once the socket 24 is fixed in to the back box 2 securely, the contacts 3D are exposed ready to receive the plug 40. The socket 24 provides a number of mechanisms to receive and retain the plug 40, The socket 24 provides a channel 33 in the inner wall of the body 23 within the lower housing 24b of the socket 24. The channel 33 is disposed towards an upper closed end of the lower housing 24b. The channel 33 is configured to be accessible via three equally spaced locating slots 33a that extend from the lower end 23b of the body 23 up to the channel 33. Each of the slots 33a tapers outwardly on one side 35a as it reaches the lower end 23b of the body 23 and provides an overhang 35b in the form of a protruding flange at the other side.

Inside the socket 24 there is also provided a clicking mechanism 34, in the form of a notch, which allows for a user to feel when the plug 40 has started and finished its rotation and also prevents the electrical device from rotating freely when in position.

The plug 40 comprises a generally cylindrical body 41 shaped to fit inside the socket 24. A first end 40a of the plug 40 is generally open, whilst a second end 4Db is generally closed. The body 41 is split into two parts comprising an upper housing 41a comprising the electrical components of the plug 40 and a lower plate 41b.

The plate 41b is integrally formed with the housing 41a by an edge portion 41c extending around approximately one quarter of the circumference of the body 41. The edge portion 41c is hollow and cooperates with holes 45a on the lower side of the plate 41b and into the base of the lower sub-housing 43b. The plate 41b is intended to be weight bearing and so, is fixed by a screw 41d to the upper housing 41a.

The upper housing 41a is further split into upper 43a and lower 43b sub-housings. The upper sub-housing 43a, which is accessible from the first end 40a of the plug 40 comprises four electrical contacts 42 for electrical connection to the contacts 30 of the socket 24. The electrical contacts 42 are in the form live 42a, neutral 42b, earth 42c and switch live 42d. The neutral 42b, earth 42c and switch live 42d contacts 42are in the form of coaxial rings, whereas, the live 42a is in the form of a ceritralised pin. The order from the middle of the plug 40 is live 42a, neutral 42b, switch live 42d and earth 42c. Insulation rings 42e are provided between the neutral 42b and switch live 42d contacts.

The lower sub-housing 43b is essentially closed off but provides screwed electrical terminals 44, which allow the terminals to be re-wireable. The terminals 44 correspond to the contacts 42 and are electrically connected to them by cables connected to the rings 42b/c/d and pin 42a inside the upper sub-housing 43a extending to the terminals 44 in the lower sub-housing 43b. Re-wiring is possible by removing the sub-housings 43 as a single unit from the upper housing 41b. The sub-housing unit is retained within the upper housing 41a by lower pins (not shown) and the sub-housing unit can be released from the upper housing 41a by simply sliding a screw driver or other implement between the walls of the sub-housing unit and the upper housing 41a in the area of a lower pin, Cables 45 pass from the terminals 44 through the hollow edge portion 41d and out of the hole 45a to exit the plug 40 and enter into connector blocks 45b and 45c. The cables from the electrical device are meant for connection to the connector blocks 45b, 45c.

The first end 40a of the body 41 provides three equally spaced locating pins 46 around its outer periphery. The pins 46 are configured to engage with the pin locating slots 33a and the channel 33 in the socket 24. Since the pins 46 can enter into any one of the slots 33a, the electrical device can be orientated appropriately, before the plug 40 is pushed properly into the socket 24, by engaging the pins 46 with the nearest slot 33a (using the taper 35a to negotiate around the flange 35b). The plug 40 is then pushed up the slots 33a to the channel 33. Upon reaching the channel 33, the plug 40 is rotated within the socket 24 to obtain the required orientation of the electrical device until the pins 46 reach the closed end of the slots 33a. The rotation allows any shape of electrical device the ability to be positioned through 360 degrees to achieve the required alignment.

In a further embodiment, the locating pins 46 function as electrical contacts. This would allow the electrical connection system to provide up to seven connections (a further three electrical contacts 46 in addition to the four previously described contacts 42a-42d), which opens up the possibility for further control signals.

The first end 40a of the body 41 of the plug 40 also provides a series of upstanding teeth 47. The teeth 47 align with the clicking mechanism 34 and allows for the user to feel when the plug 40 has started and finished its rotation. The teeth 47 engaged with the clicking mechanism 34 also resist the electrical device rotating freely when in position which keeps the device safely in its final chosen location. Should the pins 46 work their way free of the channel 33 and drop down the slots 33a, the overhang 35 of the slots provide a safety drop feature.

In this case, should the other plug 40 retaining features fail and the plug 40 should fall downwardly, the overhang 35 will catch the pins 46. The user then can simply slightly rotate the plug 40 to release it from the socket 24.

The plug 40 is electrically connected to an electrical device via the blocks 45b and 45c. However, the plug 40 is also mountably connected to the electrical device. Figure SD shows a standard light fitting 105 with a standard bracket 106, to which the plug 40 is easily mountable. However, not every light fitting 105 comes with such a bracket and either the plug 40 will not fit on the standard bracket, or the standard bracket is absent.

Accordingly, the system comprises an adjustable suspension bracket 60 as shown in Figures SA -C. The bracket comprises a rectangular suspension plate 61 with a pair of longitudinally aligned slots 62 therein. One of the slots 62 comprises a screw and nut arrangement 63, whilst the other slot 62 comprises a screw and u-shaped clamp arrangement 64. The latter arrangement 64 can be used where the electrical device has no central fixing area. A third arrangement 65 is provided for electrical devices having a central fixing rod or chain for securing it, in the form of a central aperture 65 to receive a threaded rod 66.

The suspension plate 61 is arranged to fix to the fitting 105 of an electrical device via one of the above arrangements 63, 64, 65.

As shown in Figure SC, the plug 40 fixes to the adaptive bracket 60 by sliding the plate 61 into the slot created between the upper 4Th and lower 41b housings of the plug 40. The bracket 60 is secured in place by engaging the screw 41d to extend across the slot, which also adds strength to the plate 41b of the plug 40.

Figure 6C shows an alternative solution for a simple pendant ring. A pendant ring body 107 of similar construction to that of a standard pendant ring is adapted to provide an integral bracket 108 comprising a short upstanding wall lOSa and a disc portion lUSb. The disc portion 108b is sized and shaped to fit within the slot provided between the upper 41a and lower 41b housings of the plug 40. In addition, the upstanding portion lOSa follows the outer shape of the lower housing 41b and is of a height to allow the plug 40 to sit essentially on a base of the pendant ring. The disc portion lOSa has a screw hole (not shown) that corresponds with the screw 41d. The pendant ring body 107 is further adapted from the standard version by providing an internally threaded, centrally located depending member (not shown that would usuDlly feed the light fitting cable into the pendant ring. With the threading of the member, an externally threaded hook shaft can be screwed into the member. The hook shaft is adapted to be hollow itself to receive the light fitting cable.

Installation of the electrical connection system will now be described.

In a first step, an aperture is precut in the mounting structure 110. The back box 2 is inserted with its first end 4a leading into the aperture until the flange 6 abuts against the lower surface of the mounting structure 110.

The electrical power supply cable is fed through one or more holes 14 in the body 4 of the back box 2. The fixing wings S are then pushed outwardly from the inside of the back box 2 to place them in an extended position within the void and against the inner surface of the mounting structure 110. If required! possible, screws are used in slots 16 to secure the back box 2 to a joist or the like.

The terminals 28 of the socket 24 are then connected to the neutral, earth and live supply cables and the socket 24 is then located in the back box 2. In order to locate the socket 24, the locking bars 31 are aligned with the gaps 26a in the lip 26 and then the socket 24 is moved upwardly until the flange 25 of the socket 24 is pressed to abut against the lip 26 of the back box 2. The socket 24 is then twisted to pass the locking bars 31 beyond the gaps 26a to prevent downward movement. The screws 22 are aligned with the holes 20a and 20b and tightening of the screws secures the socket 24 in the back box and also clamps the back box 2 in place by pulling the spikes 7 of the wings S against the inside of the mounting structure 110.

The above steps in the method can be performed by an electrician in isolation of the following steps.

Separately, the suspension bracket 60 is fixed to the plug 40 as described previously. The bracket 60 is then fixed to the electrical device using any one of the three optional mechanisms 63,64,65 as described previously.

The blocks 45a and 45b are then connected to the cables on the electrical device. These latter steps can be performed safely by a non-electrician.

The plug 40 is offered to the socket 24 by aligning the plug 40 pins 46 with the slots 33a as previously described, then moving the plug 40 into the socket 24 to reach the channel 33. The rotation of the plug 40 in the socket 24 secures the plug 40 within the socket 24. The teeth 47 minimise further unintentional rotational movement in the channel 33.

Now the contacts 42 of the plug 40 are aligned and in electrical contact with their respective contacts 30 in the socket 24. Since the contacts 30 of the socket 24 are diametrically disposed and the contacts 42 of the plug are concentrically disposed at corresponding distances across the diameter of the plug 40, no matter what orientation the plug is in in the socket 24, the contacts 30,42 are always electrically contacted with one another.

Furthermore, due to the concentric arrangement of the socket 24 and the plug 40, it is impossible to align the contacts 30,42 dangerously.

Since the plug 40 is already electrically and mountably connected to the electrical device, once the plug 40 is mounted in the socket 24, the electrical device is firmly electrically and mountably connected to the mounting surface 110.

In Figures 3A, 3B and 6A-C, use of the system with different light fittings 101, 102 can be seen.

With this system, any surface mounted electrical device can be adapted and installed. In the case of a light fitting, this can facilitate easy interchangeable lighting. It only takes one person to install any aspect of the product and the supply cables are always safely contained within the ceiling void after installation of the back box 2. The rest of the circuity of the system is inaccessible when the plug 40 is connected to the socket 24.

Disconnection of the plug 40 from the socket 24 removes the power supply thereby removing the possibility for electric shock. Both the electrical connection and weight of an electrical device is supported by the system simultaneously. The system isfurther userfriendly, since an electrician can install the back box 2 and the socket 24. The consumer need only then connect the plug 40 to the electrical device at no risk to themselves. The system is further adaptable to facilitate Ethernet over power adapters through lighting circuits, for example.

Although a few preferred embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention, as defined in the appended claims.

Claims

CLAIMS1. An electrical connection system for detachably connecting an electrical device to electrical supply cables, comprising: a plug being electrically connectable to an electrical device, a socket being electrically connectable to electrical power supply cables, said socket being adapted to provide a mounting connection with said plug and an electrical connection with said plug via corresponding contacts, wherein the mounting connection is releasable and further allows the plug to be rotatable in said socket, and the corresponding contacts of the socket and the plug are arranged so that when the plug is mounted in the socket the contacts are electrically connected with one another in any rotation of the plug in the socket, wherein the plug comprises a housing comprising the plug contacts and corresponding electrical terminals, characterised in that the mounting connection between the plug and socket comprise cooperating parts in the form of locating pins around an outer periphery of the housing configured to engage with an open end of pin locating slots in the socket leading to a mounting channel and the locating pins are rotatable around the channel.
2. A socket for an electrical connection system for detachably connecting an electrical device to electrical power supply cables behind a mounting structure, the system comprising support means for location substantially behind the mounting structure, said support means comprising the socket, the socket being electrically connected to power cables, and the socket being arranged to receive a plug for electrical connection to the electrical device, said socket being adapted to provide a mounting connection with said plug and an electrical connection with said plug via corresponding contacts, wherein the mounting connection is releasable and further allows the plug to be rotatable in said socket, and the corresponding contacts of the socket arranged so that when the plug is mounted in the socket, the socket contacts are electrically connected with the plug contacts in any rotation of the plug in the socket, characterised in that the mounting connection provided by the socket comprises cooperating parts in the form of open-ended pin locating slots leading to a mounting channel adapted to engage with plug locating pins for rotation around the channel.
3. A plug for an electrical connection system for detachably connecting an electrical device to electrical power supply cables in a mounting structure, the system comprising a socket for receiving the plug, wherein said socket is connectable to electrical power supply cables; said plug being adapted to have a mounting connection with said socket and an electrical connection with said socket via corresponding contacts, wherein the plug is electrically connectable to an electrical device, wherein the mounting connection is releasable and further allows the plug to be rotatable in said socket, and the corresponding contacts of the plug are arranged so that when the plug is mounted in the socket, the plug contacts are electrically connected with the socket contacts in any rotation of the plug in the socket, wherein the plug comprises a housing comprising the plug contacts and corresponding electrical terminals, characterised in that the plug comprises cooperating parts for the mounting connection in the form of locating pins around an outer periphery of the housing configured to engage with an open end of pin locating slots in the socket leading to a mounting channel such that the locating pins are rotatable around the channel.
4. The system according to any one of claims 1-3, wherein the contacts in the socket are arranged across a diameter of the socket at predetermined distances from one another.
5. The system according to claim 4, wherein each of the contacts of the plug are arranged concentrically within the plug and at a diameter position corresponding to the predetermined distances of the contacts in the socket.
6. The system according to any one of claims 4 to 5, wherein the concentric contacts of the plug comprise a central pin surrounded by coaxial rings.
7. The system according to claim 6, wherein a live contact is substantially centralised in the socket.
8. The system according to claim 7, wherein a socket neutral contact and a socket switch live contact are diametrically opposed on opposite sides of the live contact,
9. The system according to claim 8, wherein the socket neutral contact and the socket switch live contact are disposed at different distances from the live contact.
10. The system according to claim 9, wherein the socket neutral contact is closer to the live contact than the switch live contact is to the live contact.
11. The system according to any one of claims S to 10, wherein a socket earth contact is disposed outwardly of the switch live and neutral contacts.
12. The system according to any one of claims 6 to 11, wherein the plug live contact is in the form of a centralised pin and the plug neutral, earth and switch live contacts are in the form of coaxial rings.
13. The system according to claim 12, wherein the plug coaxial rings depend outwardly frorr the live pin in the order of neutral, switch live and then earth.
14. The system according to any one of claims 4 to 13, wherein at least one insulation ring is provided between the plug contacts and at least one insulation ring is provided between the socket contacts.
15. The system according to claim 14, wherein the socket comprises an insulation ring to insulate the live contact from the neutral and switch live contacts.
16. The system according to any one of claims 14 or 15, wherein the socket comprises an insulation ring to insulate the neutral and switch live contacts from the earth contact.
17. The system according to any one of claims 14 to 16, wherein the plug comprises an insulation ring to insulate the neutral contact from the switch live contact.
18. The sysLem according Lo ally one ol claims 1 La 17, wherein Lhe sysLem IurLher comprises a supporL means for location in an aperture of a mounting structure.
19. The system according to claim 18, wherein the support means comprises a mounting means for mounting the support means substantially behind the mounting structure.
20. The system according to claim 19, wherein the mounting means comprises a retractable bearing means for bearing against a surface behind the mounting structure.
21. The system according to claim 20, wherein the mounting means also comprises a flange to abut the mounting structure and retain the support means in the aperture.
22. The system according to any one of claims 18 to 21, wherein the support means comprises a retention means for the socket.
23. The system according to claim 22, wherein the retention means comprises a retaining lip for engagement with locking bars on the socket.
24. The system according to claim 23, wherein the locking bars are rotatable over the retaining lip and the retention means comprises a securing means to stop further rotation.
25. The system according to any one of claims 18 to 24, wherein the socket provides eectrical terminals connected to the contacts and the terminals are connected to electrical supply cables after passing through apertures in a support means housing and a socket housing.
26. The system according to any one of claims 18 to 25, wherein the socket sits substantially wholly within the support means.
27. The system according to any one of claims ito 26, wherein the socket comprises an upper housing that is substantially separated from a lower housing, the lower housing being open at a lower end and comprising the socket contacts.
28. The system according to claim 27 when dependent upon claim 25 or 26, wherein the upper housing is substantially closed and comprises the electrical terminals for connection to the electrical supply cables.
29. The system according to any one of claims ito 28, wherein the plug comprises a mount integrally formed with the housing and comprising a weight bearing flange or plate.
30. The system according to any one of claims ito 29, wherein the housing is further split into upper and lower sub-housings.
31. The system according to claim 30, wherein the upper sub-housing is open at a first end comprises the plug contacts.
32. The system according to any one of claims 30 or 31, wherein the lower sub-housing is essentially closed off and provides the plus electrical terminals which correspond to the plug contacts.
33. The system according to claim 32, wherein cables corresponding to the plug electrical terminal exit the lower housing and are connected to one or more electrical chip blocks.
34. The system according to any one of claims 1 to 33, wherein the locating pins comprise further electrical contacts allowing for additional lighting control signals.
35. The system according to any one of claims ito 34, wherein the mounting connection comprises a rotation resisting means in the form of teeth on the plug for enragement with a notch in the socket.
36. The system according to any one of claims ito 35, wherein the pin locating slots in the socket comprise an overhang extending from one side of the slots at the open end.
37. The system according to claim 36, wherein the pin locating slots in the socket comprise an outwardly tapered portion to widen the open end that would be otherwise closed by the overhang.
38. The system according to any one of claims 1 to 37 comprising an adjustable suspension bracket for connecting the plug to an electrical device.
39. The system according to claim 38, wherein the bracket comprises a rectangular suspension plate for engagement with the slot above the plate of the plug.
40. The system according to any one of claims 38 or 39, wherein the bracket comprises at least one form of mounting to an electrical device.
41. A pendant ring for a light fitting comprising a ring body, with a substantially centralised aperture therein, the ring body comprising an integrally formed mounting structure for a plug as described in any one of claims 3 to 40.
42. The pendant ring of claim 41 wherein the mounting structure comprises a disc member for engaging with a slot in the plug.
43. A method of installation of an electrical connection system, comprising: mounting a support structure in a mounting structure and passing electrical supply cables into a housing of the support structure; mounting a socket in the support structure comprising open-ended of pin locating slots in the socket leading to a mounting channel, and electrically connecting the cables to terminals housed within the socket to supply power to socket contacts also housed within the socket; providing a plug with a housing comprising electrical contacts and electrical terminals for electrical connection to an electrical device, and locating pins around an outer periphery of the plug housing; and releasably mounting the plug in the socket in any rotation to provide an electrical supply to the plug for supply to said electrical device via the plug and socket contacts, by locating said locating pins in the pin locating slots and rotating the pins around the channel,
44. The system according to any one of claims ito 42, wherein the electrical device is a light fitting.