WO2009004300A2

WO2009004300A2 - Screed floor outlet box

Info

Publication number: WO2009004300A2
Application number: PCT/GB2008/002173
Authority: WO
Inventors: Thomas Doherty; John Robert Harrison; Daniel John Richardson
Original assignee: Novar Ed & S Limited
Priority date: 2007-06-29
Filing date: 2008-06-25
Publication date: 2009-01-08
Also published as: WO2009004300A3; GB2450554A; GB0712719D0; IE20080528A1

Abstract

A screed floor outlet box includes a base assembly (5) that includes a base frame (9) for attaching to a floor substrate over which a screed is to be laid, and a lid frame assembly (7) for fastening to the base assembly (5). The bas frame (9) is formed from metal sheet bent approximately into the shape of a cuboid and comprising a bottom face (11), side faces (13) and an open top over which the lid frame assembly (7) is to be received. The base frame is formed from a single metal sheet.

Description

Screed Floor Outlet Box

The present invention relates to service outlet boxes, and in particular to screed floor service outlet boxes. Service outlet boxes are typically used in offices, factories or other commercial premises in which electrical or electronic services are required at a variety of different locations. Such service outlet boxes are typically fitted in the floor. The electrical or electronic services available from such service outlet boxes may for example include telephone, Internet, network and other telecommunication- or data-related services, and electric power. Service outlet boxes for installation within the floor space are particularly beneficial in offices or buildings that require flexible usage of the space within the building. Providing such service outlet boxes in several locations in a floor space may for example enable the floor space to be partitioned with quick- to-fit partition walls and to be readily used without needing to route cables through or from walls in the partitioned space.

A first type of outlet box for use on screed floors is often referred to as a screed floor outlet box. It is used when cables are to be laid in a screed laid over a floor substrate. Before the screed is deposited, cable ducts are laid on the floor substrate and screed floor outlet boxes placed at desired locations at junctions of the ducts. A box may be placed at the end of a single duct or at a junction of two, three or four ducts as may be required. The ducts and the floor boxes are secured to the floor substrate with ends of the ducts inserted into openings in side faces of the boxes. Thereafter a screed, for example of concrete, is deposited over the floor substrate covering over the ducts but leaving the tops of the screed floor outlet boxes exposed. A second type of outlet box for use on raised floors is often referred to as a raised floor outlet box. It is used when cables are to be laid below a raised floor. In this case holes are formed in the floor- at the locations where the raised floor outlet boxes are required and cables are laid under the floor to make the required connections to the outlet boxes. Ducts are not necessarily provided under the floor because the cables can simply lie freely in the space below the floor. The raised floor outlet box can be attached to the floor with its base simply suspended from the floor.

The design requirements for the first and second types of outlet box have some issues in common but are different in other respects. One particular difference arises from the requirements imposed on the box by virtue of its typical method of installation. In the case of a raised floor outlet box, the box is when first installed placed in the opening in the floor with only its top exposed and the base of the box suspended in free space below the floor. Thus, the base of the box is in a protected environment. In the case of a screed floor outlet box, however, the bottom of the box is first attached to the floor substrate and the box extends upwardly therefrom and, because when the screed is laid it remains exposed, projects to a higher level than, for example, the ducts. Even after laying of the screed the bottom of the box is in contact with the floor substrate and there remains the possibility for substantial loads to be transmitted through the box. Thus the box may be exposed to high vertical and transverse loads prior to laying of the screed and to high vertical loads after laying of the screed. A consequence of the matters referred to above is that the structural requirements for the base of a screed floor outlet box are much more severe than those of a raised floor outlet box. It may be noted that there is also at least one other type of floor outlet box, namely that which is often referred to as a flush mounted floor box and which is mounted in the top of ducting which itself is laid on a floor substrate and is flush with a screed laid on the floor. In this type of floor box, although a screed is involved, the box is mounted in the ducting and the base of the box suspended in free space within the ducting. Thus the base of the box is again protected, in this case by the ducting, in a similar way to that in which the base of a raised floor outlet box is protected by the raised floor.

A known screed floor outlet box comprises a multi-piece base frame including a rectangular base plate, side-walls and cast blocks attached at each corner. This known outlet box is secured to the floor substrate using a fastener placed through a hole in each of the corners of the base plate. The use of cast blocks at the corners of the base frame is considered necessary to provide the base frame with sufficient structural strength to meet the requirements imposed on it, especially during installation. The cost of a base frame incorporating such cast blocks is however relatively high, both in terms of cost of materials and cost of assembly.

The present invention seeks to mitigate or remove at least one of the above-mentioned disadvantages .

According to the invention there is provided a screed floor outlet box including a base assembly that includes a base frame for attaching to a floor substrate over which a screed is to be laid, and a lid frame assembly for fastening to the base assembly, wherein the base frame is formed from one or more metal sheets bent approximately into the shape of a cuboid and comprising a bottom face, side faces and an open top over which the lid frame assembly is to be received.

By providing a base frame that is formed from metal sheet, we have found that it is possible to substantially reduce the cost of manufacture of the base frame whilst still maintaining a base frame of sufficient strength to be suitable as the base frame of a screed floor outlet box.

The base frame is preferably formed from a single metal sheet. By using a single sheet, cost is reduced and there is no joint between sheets that could otherwise represent a line of weakness in the structure.

Preferably, openings are provided in one or more side faces of the base frame. In use, ducts can be connected in the one or more openings to define cable conduits leading into or out of the base frame. Depending on the particular pattern of ducting employed and the particular location of the box within that pattern, there may be one, two, three or four ducts connected to respective side faces of the base frame. The outlet box is therefore preferably provided with a respective opening in each of the side faces of the base frame. One or more side plates are preferably provided for attaching to any of the one or more openings for closing over the openings to which the ducting is not attached. Such side plates prevent the entry of screed into the outlet box during laying of the screed.

At least one side face of the base frame preferably includes a laterally projecting flange which preferably projects inwardly. Such a flange provides additional strength to the side walls of the outlet box. The or each laterally projecting flange preferably borders a respective one of the openings in the side faces of the base frame. By providing the flange as a border to the opening, it becomes, possible to make the flange in a simple manner simply by folding inwardly a portion of the side face of the base frame that would otherwise have been cut away to form the opening. Preferably the or each laterally projecting flange borders a top edge of a respective one of the openings in the side faces of the base frame. The laterally projecting flange preferably defines a horizontal ledge above the opening that it borders.

Portions of said one or more metal sheets are preferably provided with lateral extensions of the side faces, each lateral extension being folded through approximately a right angle to lie adjacent another side face to which it is secured, for example, by welding. The use of such folded lateral extensions again increases the strength of the box significantly whilst maintaining a simple and economical design.

The lid frame assembly is preferably fastenable to the base assembly through a mechanism which allows the vertical separation of the lid frame assembly from the base frame assembly to be adjusted. The mechanism is preferably a ratchet mechanism. With such an arrangement the height of the top of the lid frame assembly can be adjusted according to the depth of a covering laid over the screed.

The base assembly preferably further includes a tray mounted in the base frame and vertically spaced from the bottom of the base frame. The tray preferably provides a structure on which sockets can be mounted. The tray is preferably mounted on a plurality of pillars extending upwardly from the bottom of the base frame and/or the edges of the tray are preferably mounted on the one or more laterally projecting flanges on the side faces of the base frame (when such flanges are provided) .

The base assembly preferably includes one or more fixing brackets for attaching the base assembly to a floor substrate over which a screed is to be laid. The one or more fixing brackets are preferably movable from a first position to a second position, the one or more brackets in the second position being suitable for attaching the base assembly to a floor bracket over which a screed is to be laid. It will be understood that the fixing bracket may be arranged to receive a variety of different types of fastener for securing the outlet box base assembly to the structure to which the base assembly is to be fixed. The fixing bracket, in the second position, preferably provides a fixing plate defining an opening through which a fastener for securing the base assembly to the structure may be placed. The opening may for example be suitable for receiving a nail or a screw.

The fixing bracket may be rotatably mounted on the base assembly so as to be moveable from the first position to the second position. In an embodiment of the invention described herein, the fixing bracket is rotatable through approximately a right-angle to move from the first position to the second position. In other embodiments of the invention, the fixing bracket may be moveably mounted in other ways. For example, the fixing bracket may be slideably mounted on the base assembly so as to be moveable from the first position to the second position. The fixing bracket, in the first position, may be positioned alongside the base assembly. The fixing bracket, in the first position, may be substantially flush with the base assembly. For example, the fixing bracket may be so dimensioned such that, in the first position, the structure of the fixing bracket lies flush against the structure of the base assembly. Thus, the fixing bracket in the first position may be protected, to some extent, from damage prior to installation of the device (for example during storage or transportation) .

The base assembly may have a larger footprint when the fixing bracket is in the second position, than when the fixing bracket is in the first position. The footprint of the base assembly will be readily identifiable to the skilled man. In the event of any uncertainly, the footprint should be interpreted as the area covered by the base assembly and fixing bracket when viewed in plan view from above.

In the second position, the fixing bracket may protrude substantially perpendicularly to an edge of the base assembly. The fixing bracket, in the second position, preferably lies substantially parallel to the bottom surface of the base assembly. The fixing bracket, in the second position, may thus extend in the plane of the bottom surface of the base assembly. The base assembly may be a number of different shapes (referring to the shape of the base assembly in plan view) . For example, the base assembly may be substantially rectangular and may or may not be substantially square.

The base assembly may comprise a multiplicity of fixing brackets each being moveable from a first position to a second position, each of the brackets in the second position being suitable for attaching the screed floor outlet box base assembly to the structure to which the base assembly is to be fixed. The fixing brackets may be located on, for example, the corners of the base assembly.

According to another aspect of the invention there is provided a floor structure comprising at least one screed floor outlet box base assembly having a fixing bracket as described herein. Preferably the floor structure comprises a screed floor outlet box mounted therein, the screed floor outlet box comprising a lid assembly and a base assembly and being in accordance with the screed floor outlet box according to any aspect of the invention as described herein. The floor structure may comprise a multiplicity of screed floor outlet boxes mounted therein. The multiplicity of screed floor outlet boxes are preferably screed floor outlet boxes in accordance with any aspect of the invention as described herein. The floor structure may comprise a plurality of screed floor outlet box base assemblies mounted on the floor substrate in preparation for the introduction of screed onto the substrate. Preferably, however, the floor structure comprises a region of screed floor (i.e. with screed laid onto the substrate) .

The floor structure may include one or more cables in the floor, the one or more cables terminating inside the outlet box at a terminal defined by a socket, to which a further cable may be attached for connecting to a device positioned above the floor in the region of the screed floor outlet box. (The term "cable" is intended to encompass any electronic, electrical or optical cord, line, wire, fibres or the like that can convey signals or power from one location to another.) The floor structure is preferably part of a building.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings of which: Figure 1 is an isometric view of a base assembly of a screed floor outlet box;

Figure 2 is an isometric view of a lid frame assembly for the screed floor outlet box of Figure 1;

Figure 3a is an exploded view of the base assembly for the screed floor outlet box according to the first embodiment of the invention;

Figure 3b is an exploded view of the lid frame assembly of Figure 2;

Figure 4 is a schematic plan view of the socket arrangement in the screed floor outlet box of Figures 1 to 3b;

Figure 5 is a schematic plan view of the socket arrangement in the screed floor outlet box of Figures 1 to 3b, showing a plug received in a socket; and Figure 6 is an isometric view of part of the base assembly of the outlet box of Figures 1 to 3b;

Figures 1 to 6 show a screed floor outlet box comprising two main portions: a base assembly 5 and a lid frame assembly 7 mountable on the base assembly.

The base assembly 5 of the outlet box is shown in Figure 1 in its packaged form ready for installation. Accordingly, the base assembly includes a screed cover 3. The screed cover 3 is typically kept in place following installation of the base assembly 5 onto a floor and prevents foreign bodies entering the base frame during construction of other parts of the floor, and especially during the laying of the screed. The screed cover 3 is removed when the lid frame assembly 7 (Figure 2 and Figure 3b) is installed.

Referring first to the base assembly 5 in detail (see Figures 1, 3a and 6) , the structure of the assembly is primarily defined by a main base frame 9. The main base frame 9 defines a cuboid with a square bottom face 11, four side faces 13, and an open upper face. It is formed from a single piece of galvanised steel plate. During manufacture, an appropriately dimensioned plate is punched out or stamped from a piece of sheet steel (the various openings and fixing holes in the main base frame are also formed in the plate during this punching / stamping procedure) . The plate is then folded in an appropriate manner such that the main base frame 9 achieves the cuboid form shown in Figures 1, 3a and 6.

The four side faces 13 of the main base frame 9 extend perpendicularly upwards from the bottom face 11. The side faces 13 include lateral extensions 13a which are folded through a right angle, and spot welded onto the neighbouring side face. This corner flange arrangement provides the base frame with extra rigidity and improves the ability to seal the screed box at its corners.

Each side face 13 has a rectangular opening 14 which may be covered by a side-plate 15a or 15b. The side plates are fixed onto the part of the base frame structure surrounding the openings. In the embodiment shown in Figures 1 to 6, two opposing side plates 15a are made of sheet steel and include three openings (not shown) for receiving electrical cables (not shown) . The other two side-plates 15b are also made of sheet metal and close the sides of the frame to which they are connected.

A laterally inwardly projecting flange 17 is located on the upper edge of each opening 14 in the side faces. These flanges 17 are formed by folding portions of the side faces inwardly towards the middle of the base frame 9. The flanges 17 serve a dual-function; they support the accessory tray 19 and also provide the base with increased structural rigidity.

The interior of the main base frame 9 houses four ratchet sleeves 21 (one positioned on the interior of each corner of the base frame) . Each ratchet sleeve 21 is a one-piece plastic moulding and is attached to the bottom surface 11 of the base frame 9 by a screw inserted from beneath the base frame. The ratchet sleeves 21 are arranged to accommodate ratchet pins 23 in the lid frame assembly (see below with reference to Figures 2 and 3b) .

There are also four support pillars 25 attached at the bottom surface of the base frame 9. The support pillars 25 are held in place on bolts inserted from beneath the base frame. Each support pillar 25 has an internal thread running through its central bore. The upper part of the pillar therefore also provides a fixing location for a short bolt inserted through a hole in the accessory tray 19 to fix the tray in place. The support pillars 25 also support the tray 19 at a height above the bottom face of the base frame 9 to allow cables and the like to be accommodated in the floor box. Two segregators 27 and two segregator adjustors 29 are provided inside the base frame 9 to manage and separate cabling (not shown) .

The top face of the base frame 9 is open for accommodating the accessory tray 19, the lid frame assembly 7 and other associated components described below.

Figures 4 and 5 (to which particular reference is now made) are schematic drawings showing a plan view of the accessory tray and the sockets of the service outlet box according to the first embodiment of the invention. For the sake of clarity, the lid frame assembly and other surrounding structure is not shown. The accessory tray 19 has a central cut-out portion 31 (see Figure 3a) through which three pairs 61a, 61b, 61c of plug sockets 63 are exposed. The sockets 63 may be in a number of different forms, however in the first embodiment of the invention, the sockets 63 are for BS 1363 three-pin electrical plugs. Further embodiments of the invention (not shown) include sockets for telecommunication devices, data transfer devices, two-pin plugs etc. The sockets are positioned at the termination of the cables (not shown) which feed into the base of the box. (The term "cable" is intended to encompass any electronic, electrical or optical cord, line, wire, fibres or the like that can convey signals or power from one location to another.) In the first embodiment, and further embodiments, all the sockets share the common characteristic that they are suitable for receiving a plug attached to a cable extending in a direction perpendicular to the direction in which the plug is inserted into the socket.

In the first embodiment of the invention, all the sockets are co-planar. In accordance with a known socket for a BS 1363 three-pin electrical plug, the sockets 63 each comprise three rectangular openings 65 arranged in a triangular formation for receiving corresponding pins on the plug. The triangular formation has a height (labelled h in Figure 4) and a width (labelled w in Figure 4) .

Each pair of sockets 61a, 61b, and 61c comprises two sockets 63 located adjacent to each other in a side-by-side relationship. The first pair 61a (located towards the bottom of the page in Figures 4 and 5) , the second pair 61b (located towards the centre of the page in figures 4 and 5) and the third pair 61c (located towards the top of the page in Figures 4 and 5) are arranged in parallel rows. The rows are parallel to the lower edge 67 of the outlet box (i.e. parallel to the width W direction of the outlet box) .

All the sockets 63 in the outlet box are similarly orientated. The socket orientation is such that when a plug 69 is received in one of the sockets 63 of the second pair of sockets 61b (see Figure 5) , the cable 71 runs directly away from the plug 69 in a direction perpendicular to the width W of the outlet box and through the cord outlets 41 (not shown in Figures 4 and 5) . The part of the cable 71 extending directly away from the plug lies in a plane parallel to the top of the outlet box. In the first embodiment of the invention, the cable 71 therefore lies in a plane parallel to the plane containing the load plate 39 (when the lid is in the closed position) .

The pairs of sockets 61a, 61b, 61c are each housed in substantially identical, rectangular, modular units (mounted in the base assembly) . The modular unit of the second

(central) pair of sockets 61b, is staggered with respect to the first and third (lower and upper) pairs of sockets 61a, 61c. The stagger is in a direction parallel to the width w of the triangular formation (and parallel to the width W of the outlet box) . The pairs of sockets are staggered such that none of the rectangular openings 65 in the sockets of the second pair 61b, overlap with any openings 65 in another socket (the overlap being considered in a direction parallel to the width w of the triangular formations).

The pairs of sockets 61a, 61b, 61c are thus staggered such that the cable 71 extending directly away from the plug 69 passes between the sockets of the first pair 61a (see Figure 5) . Thus, plugs which are received in the sockets of the first pair tend not to obstruct the cable 71 extending away from the plug 69 in the second pair. This arrangement may therefore mitigate undesirable stresses on the plug 69, when a large number of the sockets are occupied. Figure 6 is an isometric view of the main base frame 9 on the screed floor outlet box according to the first embodiment of the invention. A fixing bracket 33 is shown in a deployed position. For the sake of clarity, only one corner of the main base portion is shown to have a bracket in Figure 6, but it will be appreciated that a fixing bracket is, in practice, mounted on each corner (see Figure 3a) .

The fixing bracket 33 is rotatably mounted on the outside of each corner of the base assembly 5. Each bracket is moveable between the deployed position (shown in Figure 6) and a stored position (shown in exploded view in Figure 3a) . The brackets 33 are each stamped from metal sheeting and are defined by two plate portions folded such that they are at right angles to one another. In the stored position, the two plate portions lie flush with the sides of the base assembly. In the deployed position, the brackets 33 protrude outwardly from the corners of the base, and define a fixing plate which is parallel to the bottom surface 11 of the base frame 9. The brackets 33 thereby define fixing locations at which the base frame can be attached to a floor substrate. In the stored position the brackets are rotated upwardly by 90 degrees from the deployed position and thus lie flush with the side faces of the base. Each fixing bracket 33 is attached to the base assembly using a rivet which passes through the lower plate portion of the bracket, and through a small hole in the base frame 9. The mounting of the fixing bracket on the base frame is a friction-fit (i.e. there is slight resistance to rotation that can be overcome by, for example, the user pulling the top of the fixing bracket away from the frame) .

Known screed floor boxes typically comprise a multi-piece base frame (for example a base plate, with cast blocks attached at each corner, and side-walls attached thereto) . These floor boxes tend to be secured to the floor substrate directly through the corners of the base plate. The bracket arrangement of the first embodiment of the invention provides a number of benefits over the above-described screed boxes. For example, the brackets in the deployed position extend outside of the interior of the base frame. The screed box of the first embodiment of the invention does not therefore tend to collect debris and foreign bodies when it is being attached to the floor (as can be a problem in known screed boxes) . Furthermore, the bracket arrangement provides a relatively cheap fixing arrangement, especially when used in combination with the one-piece base frame. Yet further, the brackets may be less prone to damage during transport, handling or installation of the floor box, than the corners of the base plate in known screed floor outlet boxes. Referring now to Figure 3b and the lid frame assembly 7 in detail, the lid frame assembly 7 generally comprises a lid frame 35, four ratchet pins 23, a lid 37 moulded from plastics material and hinged to one edge of the lid frame 35, and a load plate 39 with a pair of cord outlets 41 associated with the lid.

The lid frame 35 is a single piece plastic moulding, and includes, at the interior of each corner, a hole 43 in which one of the ratchet pins 23 is housed. The ratchet pins are held in the holes 43 by way of a snap-fit which substantially prevents axial movement of the pin, but allows the pin to rotate about its axis in the hole.

The lid frame 35 has complementary dimensions to the bottom face of the base assembly 5. Thus when the lid frame assembly 7 is lowered onto the base 5, the four ratchet pins 23 are received in the ratchet sleeves 21 in the base assembly 5.

The ratchet pin 23 and the ratchet sleeve 21 at each of the four corners of the box, together define a ratchet mechanism that selectively allows movement in a direction along the axis of the ratchet pin 23. The lid frame 35 of the box may thus be moved relative to the base 5, by means of the ratchet mechanisms 21, 23. This ensures that the lid both (a) lies flush and level with the surrounding floor and (b) is secured in place. The ratchet mechanisms also allow the lid to self-level over time if there is settlement or movement of the floor or its covering over time.

The ratchet pin 23 may be twisted by 90 degrees about its axis between a locked position and a release position. In the locked position the ratchet mechanism defined by the pin 23 and sleeve 21 prevents the lid frame 35 from being lifted off the base of the box. In the release position, the ratchet mechanism is disengaged. Thus, when the ratchet pins 23 of all four ratchet mechanisms are twisted to the release position, the lid frame 35 and lid 37 may be lifted off and completely removed from the base of the box 5. To facilitate twisting of the ratchet pins 23 between the locked position and release position, the top of the each pin is provided with a protrusion 23a which the user can manipulate to rotate the pin about its axis. The orientation of the protrusion 23 also allows the state of the pin to be readily identified. The lid 37 is hinged to the lid frame 35 along its rear edge (as shown in Figure 3) . The lid 37 is therefore moveable from the closed position (as shown in Figures 2 and 3) to an open position (not shown) for providing access to the space inside the box, and thus access to the sockets exposed through the cut-out in the accessory tray 19.

To facilitate opening and closing of the lid 37, a handle 45 is provided of inverted U-shape. The downwardly extending arms of the handle 45 are slideably mounted in two cylindrical housings 47 in the lid (but have inwardly bent ends that are constrained at the top of the cylindrical housings such that they cannot be completely removed) . The top of the handle 45 is therefore able to lie flush with the lid surface whilst it is not being used, but can be lifted slightly away from the lid surface to provide the user with a better grip when the lid 37 is to be opened.

The underside of each of the cylindrical housings 47 is closed. This removes the possibility of the handle arms contacting any electrical cabling inside the outlet box.

During use of the outlet box, cables from plugs connected to the sockets, pass out of the box through the lid via the cable outlets 41. The cable outlets 41 are rotatably mounted on the lid 37 and moveable between closed positions (see Figure 2) in which they are flush with the lid assembly 7, and open positions is which they are raised above the surface to allow the cables to pass out of the box.

The lid frame assembly 7 includes a metal load plate 39 coupled with the lid 37. The load plate 39 supports and distributes loads experienced by the outlet box during use (for example loads caused by people walking or standing on the box) . The load plate 39 is cut-away at the locations of the cord outlets and thus includes three protrusions on its front edge between which two recesses are defined. The central protrusion 48 includes two scalloped recesses 49 in its top face to improve the stiffness/load bearing capacity of the plate. The two side protrusions 51 are flat.

When the lid is assembled, the outer protrusions on the load plate 39 are located under corresponding projecting moulded parts of the lid. A dummy module 57 (comprising a unitary plastic moulding) is fitted over the central protrusion 48. In other embodiments, the dummy module may be replaced by, for example a locking module. The provision of the three protrusions gives the lid assembly of the floor box an improved load bearing capacity.

Whilst the present invention has been described and illustrated with reference to a particular embodiment, it will be appreciated by those of ordinary skill in the art that the invention lends itself to many different variations not specifically illustrated herein. It will also be appreciated by the reader that integers or features of the invention that are described as preferable, advantageous, convenient or the like are optional and do not limit the scope of the independent claims .

Claims

Claims:

1. A screed floor outlet box including a base assembly that includes a base frame for attaching to a floor substrate over which a screed is to be laid, and a lid frame assembly for fastening to the base assembly wherein the base frame is formed from one or more metal sheets bent approximately into the shape of a cuboid and comprising a bottom face, side faces and an open top over which the lid frame assembly is to be received.

2. An outlet box according to claim 1, wherein the base frame is formed from a single metal sheet.

3. An outlet box according to claim 1 or 2, wherein openings are provided in one or more side faces of the base frame.

4. An outlet box according to claim 3, wherein a respective opening is provided in each of the side faces of the base frame .

5. An outlet box according to any preceding claim, wherein at least one side face includes a ' laterally projecting flange.

6. An outlet box according to claim 5, wherein the flange projects inwardly.

7. An outlet box according to claim 5 or 6 when dependent upon claim 3 or 4, wherein the or each laterally projecting flange borders a respective one of the openings in the side faces of the base frame.

8. An outlet box according to claim 7, wherein the or each laterally projecting flange borders a top edge of a respective one of the openings in the side faces of the base frame.

9. An outlet box according to any preceding claim, in which portions of said one or more metal sheets are provided with lateral extensions of the side faces, each lateral extension being folded through approximately a right angle to lie adjacent another side face to which it is secured.

10. An outlet box according to any preceding claim, wherein the lid frame assembly is fastenable to the base assembly through a mechanism which allows the vertical separation of the lid frame assembly from the base frame to be adjusted.

11. An outlet box according to claim 10, wherein the mechanism is a ratchet mechanism.

12. An outlet box according to any preceding claim, wherein the base assembly further includes a tray mounted in the base frame and vertically spaced from the bottom of the base frame.

13. An outlet box according to claim 12, wherein the tray is mounted on a plurality of pillars extending upwardly from the bottom of the base frame.

14. An outlet box according to any preceding claim, wherein the base assembly includes one or more fixing brackets for attaching the base assembly to a floor substrate over which a screed is to be laid.

15. An outlet box according to any preceding claim, wherein the one or more fixing brackets are movable from a first position to a second position, the one or more brackets in the second position being suitable for attaching the base assembly to a floor substrate over which a screed is to be laid.

16. A screed floor outlet box substantially as herein described with reference to and as illustrated by the accompanying drawings .

17. A floor structure comprising a floor substrate, a screed floor outlet box attached to the substrate and a screed laid over the floor substrate and surrounding the screed floor outlet box, the screed floor outlet box being in accordance with any preceding claim.

18. A floor structure according to claim 17, including one or more cables in the floor, the one or more cables terminating inside the outlet box at a terminal defined by a socket, to ^• which a further cable may be attached for connecting to a device positioned above the floor in the region of the screed floor outlet box.