GB1576607A

GB1576607A - In-line multi-socket outlet unit

Info

Publication number: GB1576607A
Application number: GB6271/78A
Authority: GB
Original assignee: BRITISH CENTRAL ELECTRICAL CO
Current assignee: BRITISH CENTRAL ELECTRICAL CO
Priority date: 1978-05-30
Filing date: 1978-05-30
Publication date: 1980-10-08

Description

(54) IMPROVED IN-LINE MULTI-SOCKET OUTLET UNIT (71) We, BRITISH CENTRAL ELECTRICAL COMPANY LIMITED, a British Company, of Briticent House, 172 Honeypot Lane, Stanmore, Middlesex, HA7 1HJ, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to in-line multi-socket outlet units. There are numerous occasions when it is desirable to provide a number of outlet sockets for, for example, mains electrical power, at a point in a building where there is only a single socket installed. sMulti-socket outlet units for this purpose are well known and typically comprise a box having a face in which there are a number of sockets in which electric plugs can be inserted. A single power cable connects the unit to, for example, the domestic main supply either by a permanent connection or via a single plug inserted in an installed wall socket. The outlet sockets of such a unit may be arranged in various ways. One common and popular arrangement is for the sockets to be arranged in line so that plugs may be inserted into the respective sockets in a corresponding side by side relationship. With such an "inline" arrangement, the outlet unit normally has an elongate shape and is typically provided at one end with an entry point for a power supply cable to supply power to the various sockets. Such an arrangement seldom has drawbacks if the in-line unit is not to be permanently mounted, but for example, simply left on the floor of a room.

When the unit is, on the other hand, to be mounted, e.g. on a wall, there can be drawbacks.

It will be appreciated that when wall mounted, the unit is normally mounted horizontally so that the individual plugs may be inserted in the unit side by side with the plug leads depending. It can then sometimes be necessary to run the mains power supply cable to the unit from a point on the opposite side of the unit to the cable entry point of the unit. In such cases, it becomes necessary to run the supply cable the full length of the unit before entering the unit at the remote end. It has even been known for in-line units to be mounted upside down in order to avoid this difficulty; but of course upside down mounting is not a satisfactory solution. Further, in some cases it is desired to connect the unit to the main supply via a cable running in a rigid cable conduit. Then it is extremely inconvenient to have to run such a rigid conduit the full length of the unit around a U-bend before entering the unit.

According to the present invention, an in-line (as hereinafter defined) multi-socket outlet unit comprises an elongate open topped box having at only one end thereof means defining at least one entry point'into the box for an electrical power cable; a substantially rigid integral elongate socket assembly mountable in the box and having socket members positioned and shaped for accommodating the pins of a plurality of three pin plugs so that the plugs are spaced in a corresponding side by side relationship along the length of the box, when the assembly is mounted therein, and three conducting paths inter-connecting the socket .members for the live neutral and earth pins respectively of the plugs; said elongate socket assembly being removably mountable in the box orientated with either end adjacent said one end of the box having the cable entry defining means; means for connecting with said socket assembly in either orientation in the box, the live neutral and earth lines of an electrical power cable entering the box by said entry point to appropriate ones of said three conducting paths, with said connecting means including means for receiving circuit breaking means for connection in series with the live line; ,and a lid for the box having holes therein adapted to register with said socket mem .bers and through which the pins of the plug can be passed to engage in said socket members, the lid being securable to close the box in either one of two orientations relative ,to the box so that the holes can register with said socket members when the socket,.as .sembly is mounted in the box in either orientation. With this multi-socket unit, the unit may be assembled to provide for cable entry from either end, relative to the orientation of the outlet sockets. Although the box of the unit has means defining a power cable entry point only at one end, the rigid integral socket assembly and the lid having the entry holes for the pins of the plugs can be assembled in either orientation relative to the box, thus enabling the unit to be used for cable entry from either end.

It may be convenient for the sockets of the unit to be slightly staggered from side to side along the length of the unit in a zig-zag arrangement, and the term "in-line" when used herein is to be construed as including this staggered arrangement. In one arrangement, the socket assembly is mountable in the box with the socket members distributed symmetrically along the length of the box. In an alternative arrangement the socket assembly is mountable in the box with the socket members distributed asymmetrically along the length of the box proportionately more to the end of the box opposite said one end with the entry point defining means, and said lid is then provided in two parts, one part having said holes therein positioned symmetrically along its length, and the other part being adapted to cooperate with either end of said one part to complete the closure of the box. A cable gripping device may be detachably mounted in the box adjacent said one end for gripping a power cable fed into the box through said cable entry defining means.

It may be the provision of such a cable gripping device that requires the socket assembly to be asymmetrically mounted in the box so as to leave space for the gripping device adjacent the cable entry end of the box.

The socket assembly and the lid or said one part thereof may be separate units, in which case the outlet unit is arranged so that the lid bears against the socket assembly when the unit is assembled so as to hold the socket assembly in place. However, it may be convenient to have the socket assembly secured to the lid or said one part thereof, so that they can be removed from the box and re-orientated as one piece.

Conveniently, the box is made of plastics or elastomeric material and said cable entry defining means comprise one or more regions of reduced thickness in the wall of the box at said one end, which region or each of which regions can be broken or cut away to provide a hole for entry of a power cable.

Said means for connecting may include one set of terminals at one end of the socket assembly for connection thereto of the power cable lines, and provision is then made for running the power cable along inside the length of the box between said entry point and the terminals when the socket assembly is orientated in the box with the terminals remote from said entry point.

Then, said means for receiving circuit breaker means may comprise a single fuse holder mounted on the socket assembly at said one end thereof.

Instead, said means for connecting may include a respective set of terminals at each end of the socket assembly, whereby the power cable lines can be connected to the set at the end of the assembly nearest said cable entry point depending on the orientation of the assembly in the box.

Then, said means for receiving circuit breaking means may comprise a pair of fuseholders mounted one at each end on the socket assembly. In this case, a fuse is inserted, in use, only in the fuse holder nearest said one end of the box, which depends on the orientation in the box of the socket assembly. However, conveniently, said means for receiving circuit breaking means may comprise a single fuse holder adapted to be mountable at either end of the socket assembly and connected when so mounted to the conducting path inter-connecting the socket members for the live pins of the plugs. In this way only a single fuseholder need be provided but it is mounted at an appropriate end of the socket assembly depending on the latter's orientation in the box.

Instead of one fuseholder, the means for receiving circuit breaking means may comprise a miniature circuit breaker.

In a preferred embodiment, the socket assembly comprises an insulating board having said conducting paths printed on a front surface thereof and each of the socket members is secured to the front surface of the board making electrical contact with an appropriate one of said paths.

An indicator lamp may be mounted on the socket assembly and connected between the live and neutral conducting paths, and the lid may then have a light transmissive window therein positioned to register with the lamp.

In a further preferred embodiment, the unit may include a frame which can be secured between the lid and the box fitting flush with the outer surface of the lid, to form a flange extending outwardly of the top of the box in the plane of the lid. With such an arrangement, the unit may be flush mounted on a wall which may be desirable for relatively permanent installation.

Examples of the present invention will now be described with reference to the accompanying drawings in which: Figure 1 is a perspective view of a multisocket outlet unit embodying the present invention having a two part lid removed to reveal the interior of the unit, and being assembled to provide cable entry from the right hand side; Figure 2 is a plan view of the socket assembly of the unit of Figure 1 illustrates how a single fuseholder is connected thereto at either end of the assembly; Figure 3 is a perspective view correspond jng to Figure 1 but showing the unit assembled to provide cable entry from the left hand side; Figure 4 is a perspective view of an assembled unit arranged for right hand cable entry and having a corner portion of one part of the lid broken away; Figure 5 is a perspective view corresponding to Figure 4 but including a frame mounted between the lid and the box so that the assembled unit can be flush mounted and; Figure 6 is a perspective view of another embodiment of outlet unit with a socket assembly secured to the lid and shown with the socket assembly and lid removed from the box.

The example illustrated in Figures 1 to 5 is a unit providing sockets in which four three-pin plugs can be inserted in a side by side relationship.

The illustrated unit is designed for use with the standard three pin 13 amp plugs commonly used in this country, but it will be appreciated that modified versions of the unit can readily be designed for use with other forms of plugs. It is normal for wall sockets for three pin plugs to be mounted in this country with the socket for the earth pin uppermost, and it is also usual for the plugs themselves to be arranged so that the plug lead enters the plug at the opposite end of the plug to the earth pin. Thus, it is- desirable and normal that in-line multisocket units enable several plugs to be inserted at the same time all the same way up and preferably all with their plug leads extending in the same direction transversely of the length of the unit. Thus, when the unit is mounted with its length extending horizontally, all the plugs can be inserted the right way up with their leads depending.

Referring to Figure 1, the illustrated unit has an elongate rectangular box 10, typically formed of an insulating material such as plastics or hard rubber. At the right hand end of the box 10 as illustrated in Figure 1 there is a hole 11 provided through the end wall of the box 10 through which an electric power cable can enter. Also at the right hand end of the box as illustrated in this Figure, a cable gripping device 12 is secured. The gripping device 12, which is also shown in Figure 3 which has the box 10 in the reverse orientation, comprises a central spindle i3 surrounded by a skirt 14 in which there are a number of gaps 15.

A power cable (not shown) entering the hole 11 in the box is passed through one of the gaps 15 and wound around the spindle 13 in a half hitch before being connected to the terminals of the unit. In this way the device 12 firmly grips the cable to prevent any tension being applied to the terminal connections if the cable is pulled from outside the box. The device 12 is a one piece unit which is secured to the base of the box 10 by means of a screw (not shown) in the centre of the spindle 13. Thus, the device 12 can be removed, if desired, by undoing the screw. With the device 12 removed, a rigid conduit for the electric power cables may be run directly through the hole 11 into the box 10 where such an arrangement is desirable. A cable gripping device is not then required.

Figure 1 shows mounted in the box 10 a socket assembly, generally indicated by the reference 16. This socket assembly is illustrated more clearly in Figure 2. The assembly comprises a substantially rigid board 17 of insulating material, having on its front surface three conducting paths 18, 19 and 20. These paths may be formed as printed circuit paths and the board 17 may be made of glass fibre reinforced plastics. Also secured to the front surface of the board 17 there are four groups of socket members 21, 22 and 23 adapted and positioned for receiving the pins of four three pin 13 amp plugs. Each socket member is a bifurcate member of a type well known in the art and each is secured to the board 17 by means of a screw 24. As can be seen most clearly in Figure 2, the paths 18, 19 and 20 are designed to interconnect the corresponding socket members of each of the four groups. Thus, path 18 interconnects all the socket members 21 for receiving the live pins of the plugs, path 19 interconnects all the socket members 22 for receiving the neutral pins of the plugs and path 20 interconnects all the socket members 23 for receiving the earth pins of the plugs.

As shown in the Figures, each of the earth socket members 23 is surrounded by a respective helical spring 25 which provides increased resilience to the bifurcate members of the socket member to ensur a good contact with a pin inserted therein. Similar helical springs may also be provided around each of the live and neutral socket members 21 and 22.

As shown in Figure 2, terminals 26 and 27 are provided at the right hand end of the socket assembly 16 for connecting the neutral and earth lines respectively of a power cable to the conducting paths 19 and 20. Corresponding terminals 28 and 29 are also provided at the left hand end of the assembly. The live line of an electrical power cable is, in use, connected to the conducting path 18 via a fuse held in a fuseholder indicated generally by the reference 30. The fuseholder comprises an insulating plate on which there are mounted spring clip connectors 31 and 32 in which the usual conducting end caps of a cylindrical fuse can be clipped. When the outlet unit is assembled and as shown in Figure 1, a metal tab 33 formed integrally with one of the spring clips 32 is inserted in a resilient socket 34 mounted on the board 17 of the socket assembly and electrically connected to the live path 18. The live line of a power cable is then connected to a terminal 35 formed integrally with the other spring clip 31 of the fuseholder. The fuseholder 30 is shown in Figure 2 with the tab 33 withdrawn from the socket 4 for clarity.

However, when the outlet unit is assembled to provide cable entry from the right hand end as illustrated in Figure 1, the fuseholder 30 is mounted at the right hand end of the socket assembly so that all three terminals 26, 27 and 35 for the power cable are adjacent the entry hole 11 and the cable gripping device 12.

The outlet unit further includes a two part lid for closing the open top of the box 10. Both parts 40 and 42 of the lid are shown removed in Figures 1 and 3. One part 40 of the lid is adapted to cover the portion of the box containing the socket assembly 16 and includes holes 41 positioned to register with the socket members 21, 22 and 23 when the portion 40 is secured to the box 10. The holes 41 are also shaped so that the pins of the plugs can be inserted through the holes to engage in the socket members. Normally, a shutter arrangement is provided for each of the sets of holes 41 for a single three pin plug and arranged to occlude at least the holes registering with the live and neutral socket members 21 and 22. A cam arrangement is normally provided associated with the hole for the earth pin of the plug to slide back the shutter to open the hole when the earth pin of a plug is inserted. Such arrangements are well known in the art and will not be described further herein.

The other portion 42 of the lid completes the closure of the box 10 and has a tongue 43 which fits under an edge 44 of the first portion 40 when the two parts of the lid are secured to the box. Thus the two parts together completely close the box. The portion 42 has an aperture 45 therein positioned to register with the fuseholder 30 when this together with the socket assembly are mounted in the box. The aperture 45 is adapted to enable a fuse 46 to be inserted through the aperture to engage in the spring clips 31 and 32 of the fuse-holder.

For this purpose the fuse 46 is located in an insertion member 47 made of an insulating material which enables the fuse to be both located in the fuseholder and also withdrawn therefrom without the need to remove the lid of the outlet unit. Fuse insertion devices of this kind are well known in the art. Desirably, the aperture 45 is also provded with a spring loaded shutter mechanism which closes the aperture when the fuse 46 and the insertion device 47 are removed. Suitable cam surfaces on the insertion device 47 and the outer face of the shutter enable the shutter to be pushed back when the fuse is to be reinserted.

An indicator lamp 50, typically a low power gas discharge lamp, is mounted on the board 17 of the socket assembly 16 by means of an insulating mounting member 51. The lamp 50 is connected between the live and neutral conducting paths 18 and 19 in series with a resistance 52, so that the lamp is illuminated whenever power is connected to the outlet unit. The portion 40 of the lid of the unit includes a window 53 formed of a transparent plastics material which registers with the lamp 50, so as to provide an indication of when the complete assembled outlet unit is connected to a source of electrical power.

As explained previously, Figure 1 illustrates the outlet unit assembled to provide cable entry from the right hand end. Both the socket assembly 16 and the fuseholder 30 can readily be removed from the box 10. In the present example, they are not in any way secured to the box 10 when mounted therein but are held in place by the lid of the box when this is secured to close the box. Thus, when the two portions of the lid are removed, the assembly 16 and the fuseholder 30 can be removed from the box and the fuseholder 30 disconnected from the assembly by withdrawing the lug 33 from the socket 34. The integral member comprising the clip 32 and the lug 33 can then itself be removed from the insulating plate of the fuseholder and remounted thereon in the reverse orientation, i.e. as illustrated in the chain dotted lines to the left of the socket assembly in Figure 2.

The removable member includes a second spring clip 60 which, when the member is reversed as shown forms together with the spring clip 1 the two clips for holding a fuse. A second socket 61 is mounted at the left hand end of the socket assembly 16 connected to the live conducting path 18 and the lug 33 can be inserted in this second socket 61. The socket assembly 16 with the fuseholder 30 at its left hand end can then be repositioned in the reverse orientation in the box 10 as shown in Figure 3. The portion 40 of the lid can similarly be secured to the box in the reverse orientation as shown in Figure 3 so that the holes 41 still register with the socket members of the socket assembly 16. Further, the portion 42 of the lid can also be secured to the box 10 to complete the closure of the box, but in this orientation the tongue 43 engages under the left hand edge 62 of the portion 40. Once again the fuse 46 and insertion device 47 can be employed to insert the fuseholder 30 when this is in its new position. Thus it can be seen that the reassembled unit as illustrated in Figure 3 provides cable entry from the left hand end.

Turning to Figure 4, the fully assembled unit is shown in perspective view with both portions 40 and 42 of the lid secured to the box 10 by means of screws 70. Further, the insertion device 47 is shown fully pushed home through the aperture 45 so that the fuse 46 is positioned in the fuseholder. A corner of the lid portion 42 is broken away to reveal that the edge of the lid portion 42, is rebated on its inner surface. The portion 40 of the lid has the same formation.

The rebate is filled in the example illustrated in Figure 4 with a filling gasket 71 so that the assembled unit has a smooth compact exterior appearance. The purpose of the rebate in the portion 40 and 42 of the lid will be apparent on reference to Figure 5 in which the unit is shown assembled with a frame 72 clamped between the lid portions 40 and 42 and the box 10. The frame 72 is rebated along its inner edge so as to co-operate with the rebated outer edges of the lid portions 40 and 42, thus firmly securing the frame 72 in position with the outer surface of the frame flush with the outer surface of the lid portions 40 and 42. The outlet unit so assembled with the frame 72 is especially convenient for flush mounting, for example in a wall of a room, whereas the arrangement illustrated in Figure 4 without the frame 72 is suitable where flush mounting is not required or where the unit is to be employed in an unmounted condition, i.e. lying on the floor.

In the present example, the single fuseholder 30 can be secured to the socket assembly 16 at either end thereof according to the orientation that is desired for the socket assembly in the box 10. However, it is quite possible to provide mounted on the socket assembly 16 a pair of fuseholders, one at each end. Then it is only necessary to mount the complete assembly with fuseholders in the box in the required orientation and insert the fuse in the fuseholder positioned adjacent the cable entry point.

Further, even when the provision is made for a single fuseholder to be mountable at either end of the socket assembly 16 this may be done in other ways. For example, the fuseholder may be designed so that it can be clipped onto the socket assembly 16 by a movement perpendicular to the plane of the socket assembly, rather than a movement parallel to the plane as in the version illustrated in the Figures.

Also, instead of a fuse and fuseholder arrangement, some other means may be provided of arranging for a circuit break when the current drawn by the outlet unit exceeds a predetermined maximum. For example, miniature circuit breakers are known for this purpose and these have the advantage that they can be reset after operation, e.g.

by pressing a reset button. Thus, provision may be made at each end of the circuit assembly 16 for mounting a miniature circuit breaker. It will be appreciated that the.expense of miniature circuit breakers makes it very much more convenient if only a single such circuit breaker is required and it is, thus, desirable that the circuit breaker can be removed from one end and reconnected at the other end of the circuit assembly 16 if the orientation of the outlet unit is to be reversed.

In the example of the invention described above, provision is made to enable an electrical power cable to be connected to the socket assembly at the end thereof nearest the cable entry point, irrespective of the orientation of the assembly in the box.

However, it is also possible to provide terminals for the power cable only at one end of the socket assembly; but then provision must be made to permit the cable to be run along inside the box between the entry point and the terminals when the socket assembly is orientated in the box with the terminals remote from the entry point.

Figure 6 illustrates such an alternative arrangement. The example of Figure 6 also has the socket assembly secured to the lid so that they can be removed from the box and reorientated as one piece.

Referring to Figure 6, a socket assembly 80 is shown mounted on the under side of a lid 81 by means of spacers 82. The socket assembly 80 may have essentially the same construction as the socket assembly 16 described with reference to Figure 2 and accordingly no further details will be given here. Also, it will be appreciated that the details of the socket assembly 80 have been omitted from Figure 6 for clarity, as have also details of the usual shutter mechanisms for the holes through the lid 81 for the pins of the plugs.

The assembly 80 is mounted with its socket members registering with the holes in the.lid 81 so as to receive pins of plugs.inl serted in respective receptacle . locations along the lid 81. The spacers 82 may conveniently be in the form of plastics rods moulded with or cemented to the lid 81.

The board of.the socket assembly.80 is then secured to the ends of these rods by a riveting process.

The socket assembly 80 differs from the assembly 16 described previously in that it includes an integral extension 83 at one end, on which is mounted a fuse holder. The fuse holder is mounted on the side of the assembly 80 facing the lid 81 and is registered with a shuttered slot in the lid to permit a fuse to be removed and exchanged, in the same way as described with reference to Figure 1. The position of the fuse holder is indicated generally by the dotted rectangle 84. A.miniature circuit breaker may be provided instead of the fuse holder.

A further difference in the socket assembly 80 is that the only terminals for connecting the lines of an electric power cable to the socket assembly are provided on the extension 83 at 85.

In Figure 6, the lid 81 and assembly 80 are shown above and removed from a box 86. The box 86 has a hole 87 through one end wall 88, through which a power cable (shown in ghost at 89) can be fed into the box. A cable gripping device 90 is positioned just inside the hole 87.

The box 86 and the lid 81 with the socket assembly 80 are arranged so that the outlet unit can be assembled with the lid 81 and the assembly 80 in either orientation relative to the box 86. In the orientation shown in Figure 6, the terminals 85 are at the opposite end of the box 86 from the entry hole 87. However sufficient space is provided in the assembled unit for the power cable 89 to run the length of the box to the terminals 85. This space may be provided between the board of the socket assembly 80 and the bottom of the box 86, or to one side of the assembly adjacent a side wall of the box. Further, suitable formations may be provided to hold the cable in position along the length of the box.

The example of Figure 6 may be adapted for flush mounting by providing a frame between the lid 81 and the box 86 in a manner similar to that illustrated in Figure 5. In fact, securing the socket assembly to the lid makes this example especially suitable for flush mounting. When flush mounting the in line socket unit, for example in a wall, it is usual first to secure the box in a cavity formed in the wall. and then to locate the socket assemblv (suitably connected up) and the lid. If the socket assembly is not secured to the lid, it is important to ensure that the box of the unit is not mounted too deenly in the wall, or else it becomes impossible to locate the lid against the box so as to retain the socket assembly in position. Such a problem does not arise if the socket assembly is secured to the lid.

WHAT WE CLAIM IS:- 1. An in-line (as hereinbefore defined) multi-socket outlet unit comprising an elongate open topped box having at only one end thereof means defining at least one entry point into the box for an electrical power cable; a substantially rigid integral elongate socket assembly mountable in the box and having socket members positioned and shaped for accommodating the pins of a plurality of three pin plugs so that the plugs are spaced in a corresponding side by side relationship along the length of the box, when the assembly is mounted therein, and three conducting paths inter-connecting the socket members for the live neutral and earth pins respectively of the plugs; said elongate socket assembly being removably mountable in the box orientated with either end adjacent said one end of the box having the cable entry defining means; means for connecting with said socket assembly in either orientation in the box, the live neutral and earth lines of an electrical power cable entering the box by said entry point to appropriate ones of said three conducting paths, with said connecting means including means for receiving circuit breaking means for connection in series with the live line; and a lid for the box having holes therein adapted to register with said sock

Claims

**WARNING** start of CLMS field may overlap end of DESC **. The socket assembly 80 differs from the assembly 16 described previously in that it includes an integral extension 83 at one end, on which is mounted a fuse holder. The fuse holder is mounted on the side of the assembly 80 facing the lid 81 and is registered with a shuttered slot in the lid to permit a fuse to be removed and exchanged, in the same way as described with reference to Figure 1. The position of the fuse holder is indicated generally by the dotted rectangle 84. A.miniature circuit breaker may be provided instead of the fuse holder. A further difference in the socket assembly 80 is that the only terminals for connecting the lines of an electric power cable to the socket assembly are provided on the extension 83 at 85. In Figure 6, the lid 81 and assembly 80 are shown above and removed from a box 86. The box 86 has a hole 87 through one end wall 88, through which a power cable (shown in ghost at 89) can be fed into the box. A cable gripping device 90 is positioned just inside the hole 87. The box 86 and the lid 81 with the socket assembly 80 are arranged so that the outlet unit can be assembled with the lid 81 and the assembly 80 in either orientation relative to the box 86. In the orientation shown in Figure 6, the terminals 85 are at the opposite end of the box 86 from the entry hole 87. However sufficient space is provided in the assembled unit for the power cable 89 to run the length of the box to the terminals 85. This space may be provided between the board of the socket assembly 80 and the bottom of the box 86, or to one side of the assembly adjacent a side wall of the box. Further, suitable formations may be provided to hold the cable in position along the length of the box. The example of Figure 6 may be adapted for flush mounting by providing a frame between the lid 81 and the box 86 in a manner similar to that illustrated in Figure 5. In fact, securing the socket assembly to the lid makes this example especially suitable for flush mounting. When flush mounting the in line socket unit, for example in a wall, it is usual first to secure the box in a cavity formed in the wall. and then to locate the socket assemblv (suitably connected up) and the lid. If the socket assembly is not secured to the lid, it is important to ensure that the box of the unit is not mounted too deenly in the wall, or else it becomes impossible to locate the lid against the box so as to retain the socket assembly in position. Such a problem does not arise if the socket assembly is secured to the lid. WHAT WE CLAIM IS:-

1. An in-line (as hereinbefore defined) multi-socket outlet unit comprising an elongate open topped box having at only one end thereof means defining at least one entry point into the box for an electrical power cable; a substantially rigid integral elongate socket assembly mountable in the box and having socket members positioned and shaped for accommodating the pins of a plurality of three pin plugs so that the plugs are spaced in a corresponding side by side relationship along the length of the box, when the assembly is mounted therein, and three conducting paths inter-connecting the socket members for the live neutral and earth pins respectively of the plugs; said elongate socket assembly being removably mountable in the box orientated with either end adjacent said one end of the box having the cable entry defining means; means for connecting with said socket assembly in either orientation in the box, the live neutral and earth lines of an electrical power cable entering the box by said entry point to appropriate ones of said three conducting paths, with said connecting means including means for receiving circuit breaking means for connection in series with the live line; and a lid for the box having holes therein adapted to register with said socket members and through which the pins of the plugs can be passed to engage in said socket members, the lid being securable to close the box in either one of two orientations relative to the box so that the holes can register with said socket members when the socket assembly is mounted in the box in either orientation.

2. An outlet unit as claimed in claim 1 wherein the socket assembly is mountable in the box with the socket members distributed symmetrically along the length of the box.

3. An outlet unit as claimed in claim 1 wherein the socket assembly is mountable in the box with the socket members asymmetrically distributed along the length of the box proportionately more to the end of the box opposite said one end with the entry point defining means, and said lid is then provided in two parts, one part having said holes therein positioned symmetrically along its length, and the other part being adapted to cooperate with either end of said one part to complete the closure of the box.

4. An outlet unit as claimed in any preceding claim wherein a cable gripping device is detachably mounted in the box adjacent said one end for gripping a power cable fed into the box through said cable entry defining means.

5. An outlet unit as claimed in any preceding claim wherein the socket assembly and the lid or said one part thereof are separate units, and the outlet unit is arranged so that the lid bears against the soc

ket assembly when the unit is assembled so as to hold the socket assembly in place.

6. An outlet unit as claimed in any of claims 1 to 4 wherein the socket assembly is secured to the lid or said one part thereof, so that they can be removed from the box and reorientated as one piece.

7. An outlet unit as claimed in any preceding claim wherein said means for connecting includes one set of terminals at one end of the socket assembly for connection thereto of the power cable lines, and provision is made for running the power cable along inside the length of the box between said entry point and the terminals when the socket assembly is orientated in the box with the terminals remote from said entry point.

8. An outlet unit as claimed in claim 7 wherein said means for receiving circuit breaking means comprises a single fuse holder mounted on the socket assembly at said one end thereof.

9. An outlet unit as claimed in any of claims 1 to 6 wherein said means for connecting includes a respective set of terminals at each end of the socket assembly, whereby the power cable lines can be connected to the set at the end of the assembly nearest' said cable entry point depending on the orintation of the assembly in the box.

10. An outlet unit as claimed in claim 9 wherein said means for receiving circuit breaking means comprises a pair of fuse holders mounted one at each end on the socket assembly.

11. An outlet unit as claimed in claim 9 wherein said means for receiving circuit breaking means comprises a single fuse holder adapted to be mountable at either end of the socket assembly and connected when so mounted to the conducting path interconnecting the socket members for the live pins of the plugs.

12. An outlet unit as claimed in either one of claims 8 and 11 wherein the fuse holder is replaced by a miniature circuit breaker.

13. An outlet unit as claimed in any preceding claim wherein the socket assembly comprises an insulating board having said conducting paths printed on a front surface thereof and each of the socket members is secured to the front surface of the board making electrical contact with an appropriate one of said paths.

14. An outlet unit as claimed in any preceding claim wherein the box is made of plastics or elastomeric material and said cable entry defining means comprise one or more regions of reduced thickness in the wall of the box at said one end, which region or each of which regions can be broken or cut away to provide a hole for entry of a power cable.

15. An outlet unit as claimed in any preceding claim wherein an indicator lamp is mounted on the socket assembly and is connected between the live and neutral conducting paths, and the lid has a light transmissive window therein positioned to register with the lamp.

16. An outlet unit as claimed in any preceding claim and including a frame which can be secured between the lid and the box fitting flush with the outer surface of the lid, to form a flange extending outwardly of the top of the box in the plane of the lid.

17. An in-line (as hereinbefore defined) multi-socket outlet unit substantially as hereinbefore described with reference to Figures 1 to 5 or Figure 6 of the accompanying drawings.