Background of the Invention !• Field of the Invention

This invention relates to a segregated duct access system.

The system herein described is of particular value when used in conjunction with a cable ducting system of the kind described in P.C.T. application PCT/AU85/00003 but may also be used with other ducting systems.

With increasing automation of offices it has become commonplace for desks and workstations to require an electricity supply outlet and/or a telephone connection and/or one or more cable connections to data processing or other equipment.

The provision of such services to a desk or other workstation at a particular location in a building usually presents problems. The problems are exacerbated when, for example, the workstation is in an open plan, broadloom carpeted area in a modern concrete floored high-rise office building.

In a high rise building it is usual for services such as electric power or telephone mains to be

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-.2 - conducted from the lower levels to higher levels in vertical service ducts. Junction boxes are then provided at each floor level and a sub-mains cable is run at each level from the vertical service ducts and extending, for example, from one side of the building to the other. The sub-mains may be laid in an underfloor main trench formed when the concrete floor is laid or in a wall duct provided for the purpose or sometimes above the ceiling.

Reticulation cables are then conducted from the sub-mains to each location on the level at which the service is required, usually in underfloor secondary ducts extending from the main trench, above the ceiling, or in wall ducts.

When power, phone and data cables need to be reticulated on each floor, and when each service is required to be segregated from each other, the ducting of mains, sub-mains and reticulation cabling becomes complicated. Ready access is required to the sub-mains for junction to mains and/or reticulation cables while the space available in which to conduct segregated cables is usually severely limited. 2. Description of the Prior Art

Various underfloor crossover units have been proposed to facilitate the crossing of cables while maintaining segregation. Such apparatus has generally been manufactured of metal, has been of complex

construction, bulky and costly to manufacture and ill equiped to provide access to the cables housed therein.

An object of the present invention is to provide apparatus and a method facilitating segregated duct access in a multi service environment and which avoids or at least ameliorates the disadvantages of the prior art. Summary of the Invention

According to one aspect the invention consists in a formation having a first plurality of parallel channels extending in a first direction, said plurality comprising at least two subsets, the channels of one sub-set being segregated from those of the other sub-set or sub-sets; and a second plurality of parallel channels extending in a direction transverse the first direction and segregated from each other, each channel of the second plurality being in communication with all the channels of one sub-set of the first plurality and being segregated from the other sub-set or sub-sets of the first plurality.

For preference the first plurality comprises at least three sub-sets of channels. Brief Description of the Drawings

A preferred embodiment of the invention will now be described by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a part sectional perspective view of a

formation according to the invention.

Figure 2 is a perspective view of a second embodiment of the formation according to the invention, and

Figure 3 is an underside perspective view of the formation of Figure 2. Description of the Preferred Embodiment

Referring firstly to figure 1 the formation is a unitary plastics moulding having side walls 1, 2, 3, 4 defining a rectangular perimeter. The moulding is formed with a plurality of longitudinally extending parallel channels 5, 6, 7 extending from side 3 to side 1.

Channels 5 are tunnel shaped having an arched roof while channels 6 and 7 are of rectangular cross-section. The Channels 5 constitute a sub-set of power channels, channel 6 constitute a sub-set of telephone channels whilst channels 8 constitute a subset of data channels. Each of the channels is partitioned from its neighbours by dividing walls 8.

The lower extremities 9 of dividing walls 8 are flat and co-planar so that the formation may sit on a flat base such as a concrete floor and if desired may be provided with an adhesive coating.

The formation is provided with troughs 10, 11, and 12 constituting a second plurality of channels, extending transverse the direction of channels 5, 6,

and 7 .

Channels 5 are roofless where they cross trough 10 so that all transverse channels 5 communicate with- overlying trough 10 but pass beneath the elevated floor 14 of trough 11 and beneath the elevated floor 15 of trough 12. Channels 5 are floorless except at trough 10 where a web 25 provides a floor.

Channels 6 are roofless where they cross transverse trough 11 so that all channels 6 communicated with overlying transverse trough 11. Channels 6 pass below elevated floor 15 of channel 12 and beneath the elevated floor 13 of transverse trough 10. Channels 6 are floorless except at trough 11 where a web 26 provides a floor.

Channels 7 are roofless at transverse trough 12 and thus communicate with trough 12 but pass beneath elevated floor 14 of transverse channel 11 and are enclosed in a tunnel defined by upright walls 17 and roof 13. Channels 7 are floorless except a trough 12 where a web 27 provides a floor.

Channels 5, 6 and 7 communicate with respective upwardly facing openings 20, 21 and 22 adjacent to edge 1.

Adjacent to edge 1 the moulding is provided with slot-like engagement formations 30 to enable a cover to be snap-lockingly engaged to the formation.

In use mouldings of the kind shown in Figure 1 may be laid (on the floor) contiguously in a side to side array, desirably with edges ,1 against a wall, and with troughs 10, 11, 12 of one aligned with corresponding troughs of the adjacent module to form extended throughs.

Tunnels 5, 6 and 7 desirably communicate with corresponding longitudinally extending underfloor ducts for example, such as described in the above entioned co-pending P.C.T. application.

The modules- of Figure 1 is covered by a hatch 31 made for example of pressed hardboard and covered by a margin of carpet 32 which is desirably adhered to the hardboard. Hatch 31 is thus hinged by_ the carpet and may be raised to give access to the underlying ducts. When the module is covered, hatch 31 is structurally supported by load bearing lands 32 of the moulding.

The edge of hatch 31 is provided with an extruded strip (not illustrated) which grips the edge between two lateral planes and which has an upper lateral flange for clamping the carpet edge to the hatch in a neat manner. The extrusion also has a downwardly extending formation engagable with engagement formations 30 of the moulding. This arrangement maintains the hatch in a closed position under normal conditions but provides access by insertion of, for example, a screw driver under the uppermost lateral

flange of the edge strip thus permitting the hatch to be raised.

In use an electricity sub-mains may be laid in trough 10, a phone sub-mains may be laid in trough 11, and data lines may be laid in trough 12.

If desired, access may be gained at any location along the extent of the troughs by raising one or a number of hatches and that may easily be accomplished without taking up the whole carpet. Connections can be made and reticulation power cables may be fed from trough 10 into a selected one or more channels 5, phone cables may be fed into any of selected channels 6 and data cables may be fed into any channels 7 and thence into reticulation ducts.

If desired phone cables may be brought from a trough 11 to a wall socket 40 via an upwardly facing opening 21 and power may be brought via an opening 20 from a trough 10 to a wall socket 41. Additionally data cables may be brought from a trough 12 to a suitable socket (not shown) .

In each case power, phone and data cables remain segregated from each other.

Because the modules have no wholly enclosed spaces, they may be moulded from plastics as a unitary article at relatively low cost. Moreover, because the modules are capable of bearing floor loads the modules do not need to be set in concrete and, having a

profile, may be retro-fitted in existing buildings.

As will be appreciated by those skilled in the art the modules need not be laid adjacent a wall. Corner units may be provided so that troughs 10, 11, 12 may be conducted around obstacles.

Instead of applying the mouldings to the floor they may be applied to the bottom of a wall in the manner of a skirting board in which case the hatch 31 may be replaced by a facia. In which case, the openings 20, 21 and 22 may communicate with corresponding under floor ducts.

The formation shown in figures 2 and 3 is similar in many respects to that of figure 1 but includes straps 45 adapted to be snap lockingly engaged with the formation to thereby retain cables within troughs 10, 11 and 12. These straps are particularly useful when the formations are disposed in the manner of a skirting board.

Although the preferred embodiments is shown in a configuration having three transverse troughs and three sub-sets of channels, other combinations may be employed. Additionally, embodiments of the invention may be made from a variety of materials and in other shapes and sizes and all such variations are deemed to be within the scope of the invention.