GB2286645A - Plastic trunking - Google Patents

Abstract

Plastics trunking is provided which positions and encloses an elongate item such as a pipe. The trunking comprises a foldable plastics member 10 and partitions 20. The partitions 20 have parts 24, 25 which interlock with complementary parts 14, 15 of the side walls of the trunking to retain the trunking in a foldable state. Also the partitions 20 have a cut-out 21 which can receive the elongate item (pipe) 26. <IMAGE>

Description

PLASTICS TRUNKING The present invention relates to trunking preferably made from a plastics material. The invention has particular application to pipework, but is also applicable to enclosing cables or other wires, or other services required to be run around a building for instance. However, the invention is best understood in relation to rigid pipes and will be described in relation thereto.

When installing pipework it is standard practice to provide clips, for instance fixed to a wall, which hold pipes in position. Also it. is common to enclose or "box-in" pipes after installation, in particular, where they would otherwise be visible, for aesthetic reasons or to provide a measure of physical protection for the pipes. This enclosing may be done by constructing a wooden box around the pipes, which requires a number of parts and some time to complete.

The present invention provides a trunking, for services such as pipes, which both fixes such services in position and provides an enclosure for them.

Preferably the trunking is provided as an elongate generally flat section having two longitudinal fold lines defining a base section and two side sections. Means are provided for fixing the base section to a wall or other surface along which a pipe or pipes is to be run and the side sections may be folded up to be generally perpendicular to the base section.

Inserts are provided which fit into the shape so formed and which inter-engage with the side sections to hold them in their folded up state. The inserts are also provided with cut-outs into which the pipes are clipped in order to be held in place. Finally a cover is provided to complete the enclosure, either as a separate element, or as a further foldable section of the initial flat section.

Such an arrangement has the advantage that installation of pipework is simplified. In particular this can be seen because once the base section of the trunking is fixed to the wall, for instance by screws, adhesives or other suitable means, the installation is completed merely by fitting the remaining parts together.

Additional flexibility can be gained by providing a number of different types of insert for one size of trunking allowing the mounting of one or more pipes of different sizes. Preferably the inserts are generally rectangular flat plastics pieces.

As described above, the inserts inter-engage with the side portions of the trunking. The inserts may be fitted into the folded elongate section either by sliding in from an end of the trunking or by clipping into place. The shapes of the inter-engaging portions may be shaped so as to facilitate one or both of these insertion methods.

In a particularly preferred embodiment the initial generally flat section is provided in a coiled state on a reel. This means that only the required lengths need be cut off the reel, thus reducing wastage.

Also a reel can be more easily stored than pre-assembled lengths.

It is further preferred that the trunking, and cover if provided separately, is manufactured as an extrusion.

The invention will be better understood from the following description of a preferred embodiment of the invention given by way of example and with reference to the accompanying drawings, in which: Fig. 1 shows a cross-section of the trunking of the preferred embodiment in its unassembled state; and Fig. 2 shows a cross-section of the assembled trunking.

The major component of the trunking of the preferred embodiment of this invention is provided as a generally flat plastics extrusion which can be coiled onto a reel for ease of storage. The cross-section of this extrusion is shown in fig. 1 and is designated by numeral 10. The trunking of the preferred embodiment further includes flat plastics inserts which provide structural rigidity to the trunking and hold pipes mounted in the trunking in position. Such an insert is shown in fig. 2 and is designated by numeral 20.

Referring again to fig. 1, the elongate extrusion 10 comprises base section 11 and side sections 12. These are defined by longitudinal fold lines 13. In use the base 11 is fixed to a wall or other suitable surface and for this purpose base 11 may be provided with screw holes or adhesive backing or other suitable fixing means.

Extrusion 10 is also provided with clips 14, 15 on side sections 12 which interlock with inserts 20 as described in detail below.

As shown in fig. 2, insert 20 is a flat plastics piece of generally rectangular shape having interlocking portions 24, 25 formed at its corners and cut-out 21 in one side. As is apparent from fig. 2 the trunking is assembled by folding extrusion 10 along fold lines 13 and sliding in insert 20, thereby engaging clips 14, 15 with portions 24, 25. Side portions 12 are thus retained generally perpendicular to base portion 11 and insert 20 is retained in position. In an installation a number of inserts 20 are positioned along the trunking at suitable intervals.

A pipe, illustrated in dotted outline by reference 26, is clipped into inserts 20 and is thereby held in position. The enclosure is completed by a cover 28 which is illustrated as being a separate member clipped in place by inter-engaging portions 29, 30.

Alternatively the cover 28 may be provided as a further foldable section of extrusion 10 which folds over into the position shown in fig. 2 and is clipped at one side only.

A number of variations on the preferred embodiment described above are possible. For instance, a number of different types of insert 20 may be provided. All would fit into folded extrusion 10, but could have more than one cut-out 21 for mounting more than one pipe in a single trunking, and/or different size cut-outs 21 for mounting pipes of- various standard sizes. Also inter-engaging means 14, 15, 24, 25 may vary in shape according to the intended method of installing the inserts 20. In particular means 14 and 24 may be omitted if it is intended that inserts 20 should be clipped into place by insertion through the open top of the trunking.

The extrusion 10 is preferably of polyvinylchoride (P.V.C.) which is semi-rigid with a "memory" for remembering shape. The extrusion can be coiled when it is not longitudinally folded (i.e. when it is in a substantially flat condition).

The material is advantageously stable at temperatures below 00C and is resistant to shattering.

A suitable material is commercially available from Plycol (PVC) Limited under the grade reference FC 15/85T and has the following approximate properties. A Cold Flex temperature of -3 C, a cold Bend temperature of -25"C and a Tensile Strength of 15.3 MN/m2.

A further suitable material is available from Norsk Hydro Polymers Limited under the grade reference XN 75467 and has the following approximate properties.

A maximum Cold Flex temperature of -6 C, a maximum Cold Bend temperature of -20 C, a minimum Tensile Strength of 15.2 MN/m2 and a nominal Shore A Hardness of 92.

In practice a coil of trunking according to the invention may be formed by producing the appropriate extruded section, cooling the extrusion by a suitable method (e.g. water, air or refrigeration), feeding the extrusion into a set of nip rollers, and winding it into a coil.

When a section of the trunking is required a suitable length may be unrolled from the coil, cut off, and straightened.

Claims (9)

1. CLAIMS: 1. Plastics trunking for positioning and enclosing an elongate item, comprising: a substantially flat elongate member of plastics material having a plurality of longitudinal fold-lines defining a plurality of elongate sections, comprising a median section and at least two wall sections; and a plurality of spanning members adapted to span the trunking to retain the wall sections angled to the median section when the trunking is in an assembled condition and to hold in a pre-determined position said elongate item.
2. 2. Plastics trunking according to claim 1 in which said spanning members and said wall sections comprise complementary parts adapted to interconnect when the trunking is in an assembled condition whereby the wall sections are retained angled to the median section.
3. 3. Plastics trunking according to claim 1 or 2 for positioning and enclosing a circular-section pipe in which said spanning members are adapted to receive said pipe.
4. 4. Plastics trunking according to claim 1 or 2 for positioning and enclosing a cable in which said spanning members are adapted to receive said cable.
5. 5. Plastics trunking according to claim 1, 2, 3 or 4 in which said spanning members are planar plastics members.
6. 6. Plastics trunking according to claim 1, 2, 3, 4 or 5 in which the median and wall sections of the elongate member are adapted to form a channel when the trunking is in an assembled condition, the elongate member includes a further foldline defining a lid section, and there is further provided closure means for retaining the lid section across the elongate opening of the channel when the trunking is in an assembled condition.
7. 7. Plastics trunking according to claim 1, 2, 3, 4 or 5 in which the median and wall sections of the elongate member are adapted to form a channel when the trunking is in an assembled condition; and there is further provided a separate lid member and closure means for retaining the lid member across the elongate opening of the channel when the trunking is in an assembled condition.
8. 8. Plastics trunking according to any previous claim, wherein the elongate member is of polyvinylchloride and is coilable.
9. 9. Plastics trunking substantially as hereinbefore described with reference to the accompanying drawings.