GB2618098A

GB2618098A - Greenhouse structure

Info

Publication number: GB2618098A
Application number: GB2206065.1A
Authority: GB
Inventors: James Davison Angus
Original assignee: Haygrove Ltd
Current assignee: Haygrove Ltd
Priority date: 2022-04-26
Filing date: 2022-04-26
Publication date: 2023-11-01
Also published as: GB202206065D0

Abstract

A gutter arrangement 20 for a polytunnel (10; Fig. 1), wherein the polytunnel comprises legs 12 carrying support hoops 16 and a cover member retained on the hoops 16 by straps 18. Gutter material 22 such as a polypropylene sheet is affixed to the legs 12 with a gutter-fastening member 30. In one aspect, the gutter-fastening member 30 includes a strap attachment structure (34, 34a, 34b, figure 5, 50, figure 9) for attachment of an anchoring strap structure to hold the straps spaced from the gutter material 22. In another aspect, the gutter arrangement 20 comprises an end plate (64; Fig. 16) mounted to a leg 12 with an adjustable spacer. The aspects allow the tension of a gutter formed from polypropylene sheet to be adjusted for water runoff distances of several tens of metres. The gutter fastening member may be attachable to the leg at a position above the gutter material, the strap attachment structure may be positionable in one of at least two positions on the gutter fastening member, each of the two positions providing a different spacing of the strap attachment structure from the gutter fastening member. The strap attachment structure may comprise two hook arms extending from a connection point, one of the two hook arms being longer than the other.

Description

Greenhouse structure

Field of the Invention

The present invention relates to guttering for polytunnel structures such as polytunnel greenhouses used for the cultivation of plants and crops. More specifically, the present invention relates to assembly structures and methods for guttering that are suitable for a wide range of materials including plastics sheet material guttering.

Background

A common form of polytunnel structure of the type used for cultivation of plants and crops comprises a series of pairs of support legs supporting a hoop or arched structure over which a cover material such as a polypropylene sheet is mounted to provide a generally semi-cylindrical or arched roof. The spacing covered by a hoop between the support legs making up a pair may be in the region of several metres, e.g. six to ten metres, and the length of a polytunnel may be several tens of metres and sometimes around 100 metres. Polytunnels may be arranged to extend side-by-side to share support legs. The cover material is usually retained on the arched structures by anchor ropes or straps extending over the cover material, to withstand wind loads, attached to the support legs and tensioned to resist a lifting off of the cover material.

Considerable development effort is directed to making polytunnel structures robust to wind loads, snow loads, and to facilitate water runoff. The elongate extension of a polytunnel allows rain water guttering to be installed along a polytunnel's length extension, at the lower end of the hoops. Several sections of guttering may be joined to extend several tens of metres or in the region of hundred metres, corresponding to the length extension of a polytunnel on a field. In installations comprising side-by-side polytunnel structures sharing support legs, conveniently, a joint gutter is provided between two adjacent polytunnels.

The process of forming longer gutter sections requires specialist shaping machinery due to the strength of the guttering material required to withstand wind loads and to maintain pre-designed water runoff angles along the length of a polytunnel.

The requirement for sufficiently strong materials and specialist forming machinery adds to cost that often results in the omission of guttering, instead allowing rainwater to run off directly into ground underneath.

The present invention seeks to provide an alternative solution for greenhouse guttering.

Summary of the Invention

In accordance with a first aspect of the invention, there is provided a gutter arrangement as defined in claim 1. The gutter arrangement is for a polytunnel structure, to be mounted along a length extension of the polytunnel structure, the polytunnel structure being of the type comprising sheet-support hoops on pairs of legs to support a cover member retained by anchoring straps. The gutter arrangement comprises a gutter-fastening member to restrict lifting of a length of gutter material from the leg, the gutter-fastening member comprising a strap attachment structure for attachment of an anchoring strap.

The sheet-support hoops may be arcuate support beams. The sheet-support hoops are typically constituted by continuous arches and may also be constituted by arches with stepped regions, in the manner disclosed in the applicant's United Kingdom patent publication GB2584838. Some variants of sheet-support hoops may be of multi-part form to accommodate vent openings. Common to such structures is the generally arcuate form supported on two lateral ends by a pair of legs. The cover member may be any suitable material although a common form uses polypropylene ("PP") sheet material.

The strap attachment structure is conveniently a hook or loop for attachment of an anchoring rope or strap. The anchoring rope or strap may be detachable from the strap attachment structure if it is desired to alter the tension of the cover member. By combining the gutter-fastening member with a strap attachment structure, assembly of a leg assembly is facilitated.

The gutter-fastening member may be considered a clamping member to hold a length of gutter material between the leg and the gutter-fastening member. However, while in some installations the gutter material may be clamped so as to be secured in place relative to the leg, in other installations the gutter material may be held by the gutter-fastening member in a manner resisting a vertical lifting off yet permitting movement (or a small degree of movement) in the horizontal direction, for instance to be able to pull the gutter material in its longitudinal extension, even if only by a small amount, to tension the gutter material between two legs, and/or to shift the gutter material laterally, e.g. to centre the gutter material to provide evenly high gutter walls.

In some embodiments, the strap attachment structure is fixed to the gutter-fastening member.

The strap attachment structure may be integral with the gutter-fastening member, or attached to it, e.g. soldered or otherwise affixed.

In some embodiments, the strap attachment structure is reposifionably attached to the gutter-fastening member.

The strap attachment structure may be attached in a manner allowing it to be repositioned, e.g. it may be removably attached. For instance, the strap attachment structure may be hooked into a corresponding loop in which it is anchored. The strap attachment structure may be hingedly connected to the gutter-fastening member, the hinge allowing the strap attachment structure to be positioned in one of several hinged positions.

The strap attachment structure may be adjustable between two or more configurations.

For instance, in one configuration, the strap attachment structure such as a hook may extend further from the leg than in another configuration. This may allow the same gutter-fastening member with strap attachment structure to be used for different anchoring rope or strap systems.

In some embodiments, the gutter-fastening member is attachable, in use, to the leg at a position above the gutter material.

The position above the gutter material may be understood as a position above the side wall formed by gutter material, This avoids the need for perforating the gutter material to affix the gutter-fastening member to the leg.

In some embodiments, the gutter-fastening member comprises an arcuate profile comprising and outer, convex, surface and an inner, concave, surface, the strap attachment structure being located on the inner, concave surface.

The convex surface of the gutter-fastening member may be used to engage or come into contact with the gutter material to provide a more intimate engagement to retain the gutter on the leg. In variants with pliable gutter sheet material, the convex surface may provide a gutter-shaping function, and/or a shape-preserving function. By locating the strap attachment structure on the concave side of the gutter-fastening member, the strap attachment structure is oriented away from the gutter material. This reduces the likelihood of, and practically avoids, that the gutter material and the strap attachment structure and any anchoring rope or strap attached to it come into contact with the gutter material. Thereby, less robust gutter material can be used than might otherwise be the case.

In some embodiments, the strap attachment structure is posifionable in one of at least two positions on the gutter-fastening member, each of the at least two positions providing a different spacing of the strap attachment structure from the gutter-fastening member.

In some embodiments, the strap attachment structure comprises two hook arms extending from a connection point with the gutter-fastening member, one of the two hook arms being longer than the other of the two hook arms.

Alternatively or in addition, the strap attachment structure may comprise a hook arm slidable or otherwise repositionable on the gutter-fastening member to achieve a different spacing of the hook arm relative to the gutter-fastening member.

In some embodiments, the gutter arrangement comprises longitudinally extending support structures supporting the length of gutter material, the longitudinally extending support structures extending across a series of legs.

The longitudinally extending support structures may be constituted by wires, ropes, or bars on either side of the gutter, effectively providing a rail for supporting the gutter material. The gutter may comprise, viewed in section, laterally extending lips, or may be made from pliable material comprising laterally extending flaps or wings, which may be hooked onto the longitudinally extending support structures.

In some embodiments, the gutter arrangement comprises a gutter formed from pliable sheet material.

In some embodiments, the sheet material comprises polypropylene.

In this manner, the sheet material may be provided as a roll of sheet material, having a length of several tens or hundreds of meters. This allows a length of continuous, uninterrupted gutter material to be provided for relatively long polytunnel structures, avoiding the need for joining individual sections of guttering.

In some embodiments, the sheet material comprises fold lines extending along the extension of the sheet material.

The fold lines may facilitate the folding of laterally extending wings along the length of the gutter sheet material. The fold lines may be spaced apart further than the longitudinally extending support structures, such that, viewed in section, wings of the sheet material hook over the longitudinally extending support structures that provide guide rails, and the remainder of gutter material between the wings may hang between the longitudinally extending support structures.

In some embodiments, the sheet material comprises pre-formed apertures spaced apart and extending along the extension of the sheet material.

The pre-formed apertures may be located close to the fold lines, formed using a suitable means such as punching. Preferably, the apertures are laterally outside the fold lines, or no more than 1 or 2 centimetres from the fold lines. Thereby, in use, the apertures are outside or relatively high on the gutter wall. The apertures may be provided as pairs on either side of a fold line (e.g., two pairs of apertures for two fold lines), spaced apart along the longitudinal extension of the sheet material. The apertures may be spaced apart in the region of 30 centimetres or more, e.g. 50 cm.

The apertures may have a diameter of no more than 3, 4, 5, 6 or 7 millimetres. The apertures allow fixation means such as wires or cable ties to be fed through the sheet material for securing to a structure such as the longitudinally extending support structures. In pre-fabricated form, the apertures avoid the need to punch holes during installation procedure, further reducing the risk of damaging the water-carrying side of the gutter material. Conveniently, the gutter material needs to be secured only at some of the pre-formed apertures. For instance, the apertures may be spaced apart 30 cms, in use between legs that are 2.5 metres spaced apart, and ties may be used at every second pre-formed aperture.

In some embodiments, the gutter arrangement comprises an end plate arrangement comprising a gutter end plate and a leg connector for connecting the end plate to a leg, the leg connector comprising an adjustable spacer allowing a distance to be altered between the gutter end plate and the leg.

In accordance with a second aspect of the invention, there is provided a gutter arrangement is defined in claim 14. The gutter arrangement is for a polytunnel structure, the polytunnel structure being of the type comprising sheet-support hoops carried on pairs of legs to support a cover member retained by anchoring straps, the gutter arrangement comprising a length of gutter material extending across a series of legs, and further comprising an end plate arrangement comprising a gutter end plate and a leg connector for connecting the end plate to a leg, the leg connector comprising an adjustable spacer allowing a distance to be altered between the gutter end plate and the leg.

In some embodiments, the leg connector is constituted by one or more bolts.

The distance-adjusting configuration may be achieved by two nuts threadedly retained on a shaft of a bolt, the end plate being retained between the two nuts, such that adjustment of the two nuts to coordinate the retention location of the end plate along the bolt results in a different spacing between the nuts and the end/head of the bolt.

In some embodiments, the gutter end plate is connected to the leg connector via a plurality of bolts in threaded engagement with the gutter end plate.

In some embodiments, the gutter arrangement comprises an arrangement of brackets for attachment to the leg, the brackets affixed to the end plate via one or more adjustable spacers.

In some embodiments, the gutter end plate is fixed to a gutter end bracket, the gutter end plate and the gutter end bracket comprising abutment structures to compress portions of gutter sheet material between them.

The portions of gutter sheet material may be flaps or lips bent from an end of a length of gutter sheet material.

In some embodiments, the leg connector is connected to the leg via a portion of a sheet-support hoop.

In some embodiments, the portion of the sheet-support hoop is mounted on the leg.

It is envisaged that the end plate is mounted at the top of a hoop-support leg. In that case, an end of a sheet-support hoop may be seated on or within a portion of the hoop-support leg. Conveniently, in that case, the end plate may be mounted to both the hoop-support leg and the sheet-support hoop.

In some embodiments, the leg is not carrying a sheet-support hoop.

The invention may be used with a leg installed to support only the end of a length of gutter material.

Any one or more of the embodiments disclosed in relation with one of the first or second aspects may be combined with any one or more of the embodiments disclosed in relation with the respective other aspect. For instance, it is envisaged that guttering may be provided as sheet material along a length of a polytunnel, secured against lifting off by gutter-fastening members located in hoop-support legs, as described in relation to the first aspect, and further comprising an end plate connection in accordance with the second aspect, allowing for an adjustment of the distance between the end plate and the leg, to allow the tension of the guttering to be adjusted, for instance for it to be tensioned for use or to loosened to facilitate repositioning. By providing the gutter-fastening members of the first aspect, the gutter material may be moveable in the longitudinal extension and thereby facilitate tensioning of the gutter material by an end plate arrangement of the second aspect.

Description of the Ficiures

Exemplary embodiments of the invention will now be described with reference to the Figures, in which: Figure 1 is a schematic illustration of a polytunnel installation; Figure 2 is a schematic illustration of a gutter arrangement extending along a length of a polytunnel; Figure 3 is a side view illustrating a pliable gutter material installed along a support leg; Figure 4 is an isometric illustration of a clamping member; Figures 5 and 6 are side views of clamping members; Figure 7 is a side view of another form of clamping member; Figure 8 is a top view of the Figure 7 clamping member; Figure 9 is an isometric view of a hook component for use with the Figure 7 clamping member; Figure 10 is an isometric view of a clamping member provided with the Figure 9 hook component; Figure 11 is an isometric view of retained guttering in a first configuration; Figure 12 is an isometric view of retained guttering in a second configuration; Figures 13 to 17 show isometric views illustrating assembly steps for an end plate component; Figure 18 shows an isometric view of another end plate embodiment; Figure 19 shows a top view of the Figure 18 end plate embodiment; Figure 20 shows an isometric view of yet another end plate embodiment; and Figure 21 shows a top view of the Figure 20 end plate embodiment.

Description

Referring to Figures 1 and 2, Figure 2 showing and enlarged portion of Figure 1, a polytunnel installation 1 comprises a series of polytunnels 10a, 10b, 10c arranged side-by-side. Each polytunnel 10a,10b,10c comprises a series of pairs of support legs 12 comprising a hoop-support end 14. Each pair of support legs 12 carries a hoop member 16. The hoop member 16 may span several meters, e.g. in the region of six to ten metres. The pairs of legs in series may be spaced apart around two to five metres, and in series extend several tens of meters, so that a polytunnel 10a may cover an area in the region of 10 x 100 metres. The hoop-support ends 14 are bifurcated, each comprising two arms 15 extending in an opposite direction, to allow a hoop-support end 14 to support the ends of two hoop members 16, such that one support leg 12 may be used as single support for, and between, two adjacent polytunnels (eg., 10a-to-10b, and 10b-to-10c). Cover material (not shown in Figures 1 and 2) such as polypropylene sheet is supported on the hoop members 16 and retained by anchor ropes or straps 18 (indicated in Figure 2), tensioned to the legs 12 to retain the cover material between the hoop members 16 and the anchor ropes or straps 18.

Each hoop-support end 14 comprises an, in use, upwardly-facing recess defined by the space between the arms 15. Guttering 20 is provided in the space between the arms 15, extending across the series of support legs 12 along the length of the polytunnel 10. It will be appreciated that the guttering 20 may preferably be installed in a manner in which it is overlapped by overhanging cover material (cover material not shown), such that rain water running off the edge of cover material is collected in the guttering 20.

Figure 3 shows a side view of a portion of a leg 12 and its hoop-support end 14, viewed in the direction of the extension of a polytunnel 10. The leg 12 may be provided between two polytunnels 10a, 10b, one arm 15a to support a hoop member 16 of the polytunnel 10a (see Figure 1) and one arm 15b to support a hoop member 16 of the polytunnel 10b (see Figure 1). Wiring 32 is attached to the arms 15a, 15b to extend along the length of the polytunnels. The wiring 32 constitutes a longitudinally extending support structure, or guide rail, for a sheet material 22. The sheet material 22 may be provided by a pliable sheet such a PP (polypropylene) sheet material. Polypropylene sheet material may be provided in rolls of several 100 metres that can be cut to length on site. This allows supplying several tens of metres of polypropylene material without interruptions, avoiding the need to connect lengths of gutter material in a fluid tight manner as would otherwise be required when combining a series of sections.

Conveniently, polypropylene sheet material can be provided with prefabricated folds or fold lines 26 extending along the length of the polypropylene sheet material. By folding the sheet material along its length, it can be shaped to comprise three regions (when viewed in section), a gutter region 24 constituted by the central portion of the sheet material between the fold lines 26, and two wing regions 28, one wing region formed at either side of the gutter region 24. The wing regions 28 may be installed to hang over the wiring 32 and allow the gutter region 24 to be suspended between two wires. It will be appreciated that the wing regions may be provided with spaced-apart notches (not illustrated in Figure 3, see Figure 11 showing a notch 27 at the wing region 28) or cut-outs corresponding to the locations of legs, to avoid interference with the arms 15.

However, when the sheet material is sufficiently pliable the notches may be omitted as this avoids the need for exact positioning of notches and/or legs.

The sheet material comprises a series of spaced-part apertures 25 (not illustrated in Figure 3, illustrated in Figures 13-17) extending along the length of the sheet material 22. In the illustrations, the apertures 25 are laterally outward of the fold lines 26, on the wings 28, and therefore the gutter region 24 is free from perforations. However, in embodiments the apertures may be provided close to the fold lines 26, laterally inward, at a location relatively high in the gutter region 24 when in use. The gutter material 22 may be secured by way of the wing regions 28 to the wiring 32 using ties 33 such as wire or cable ties (see Figures 11 and 12). The ties 33 resist a lifting off the gutter material 22 from the wiring 32 although may be sufficiently loose to permit longitudinal sliding of the gutter material 22 along the wiring 32. Thereby the guttering may be better secured, if desired, to the longitudinally extending support structures between legs 12, without however limiting the ability for the gutter material to slide in the longitudinal extension, if it was desired to tension it. If provided in the form of wings hanging over wires and secured with wires or cable ties, the guttering may also be able to move laterally by a degree permitted by the looseness of the ties. Thereby the guttering is more resilient to some lateral wind loads.

Preferably, the sheet material is dimensioned such that the gutter region 24 fits into the space between the arms 15a, 15b and between the wiring 32. In practice, the arms 15a, 15b may be provided with eyes or hoop structures on or through the arms 15a, 15b, through which wiring may extend.

The Figure 3 arrangement allows a gutter region 24 to be provided that is suspended laterally from longitudinally extending support structures (here, in the form of wiring 32), and avoids the need for fixing means extending through the gutter region 24, which is therefore unperforated, avoiding a discontinuity in sheet material that would otherwise require sealing.

Figure 4 shows a clamping member 30 for securing the sheet material 22 to the leg 12. The clamping member 30 comprises a band of rigid material such as metal, which may be aluminium or corrosion-resistant metal such as steel, or may be pre-formed from other suitable materials such as rubber or plastics. The clamping member 30 comprises a generally smooth sheet-facing side 31 On use, the underside of the clamping member 30) that is convexly curved in a manner corresponding to the curvature contour of the hoop support end 14 between the arms 15. The clamping member 30 comprises two free ends provided with notches (notches not shown in Figure 4, see notches 46 in Figure 8) to which connecting clamps 38 may be attached, the notches helping to retain hoops of the connecting clamps at a predefined distance, and thereby at a pre-defined height, along the free end of the clamping member 30. Thereby, an arrangement is provided that allows the gutter-fastening member to be secured to a leg it a position, in use, above the gutter material. Instead of connecting clamps, other attachment elements, for instance shackle-type structures, wire, or the like, may be used, to affix the clamping member 30 to a leg 12. Likewise, the clamping member 30 may be affixed to the leg 12 directly using a bolt, screw or the like. The connecting clamps or other attachment elements may be integrally connected with the clamping member. However, the provision of separate attachment members such as connecting clamps is believed to render the system more versatile for use with different pre-existing leg designs and hoop members, including hoop members slotting over the leg arms, as the same clamping member 30 may be used with differently dimensioned connecting clamps (or other attachment means) as may be required for a particular leg geometry.

The concave, or inner, side of the clamping member 30 is provided with a strap attachment structure 34 comprising two hooks for attachment of anchor ropes or straps 18. It will be appreciated that a single strap attachment structure may comprise two opposing hook ends, one each for an anchor rope or strap 18 one either side, for adjacent polytunnels extending side-by-side. The strap attachment structures 34 are located in a deeper region of the clamping member 30, close to the centre of the clamping member 30. In that manner, the free ends of the clamping member 30 extend beyond the strap attachment structure (conversely, the strap attachment structures are within the top line defined by the clamping member 30 in use), such that a cover member (not shown) retained by the anchor rope or strap may overlap and/or overhang the clamping member 30.

Figures 5 and 6 show two different variants 30a, 30b of the clamping member 30. The clamping members comprise the same band of rigid material as shown in Figure 4, but are provided with two different strap attachment structures 34a, 34b. The description of integers shown in Figure 4 is not repeated for Figure 5 and 6. The clamping member 30a of Figure 5 comprises a strap attachment structure 34a with hooks spaced from the sheet-facing side 31 by a spacer portion 36. The clamping member 30b of Figure 6 comprises a strap attachment structure 34b in which the hook is close to the sheet-facing side 31. It will be appreciated that an anchor rope or strap 18 tensioned to the Figure 5 attachment structure 34a is spaced further from the hoop support end 14 than the Figure 6 arrangement. As such, different hook shapes allow different anchoring points to be provided, which may be necessary for different tensioning systems. For instance, some polytunnel systems comprise a motorised sheet-roll-up mechanism that may require a somewhat slacker anchor rope arrangement that can be provided by a longer (further spaced-apart) strap attachment structure. In this manner, if it was desired to retro-fit a motorised sheet-roll-up mechanism, a clamping member of the type of Figure 6 might be replaced by a clamping member of the type of Figure 5, without requiring a removal of guttering and/ without requiring an fixtures to be inserted through the gutter sheet material.

Figures 7 and 8 show a further variant of a clamping member 40 in side view and top view, respectively. The clamping member 40 comprises a main band body 42 of rigid form generally corresponding to the band of the clamping member 30. The main band body 42 may be from a suitable material such as metal, plastics and/or rubber material.

At its free ends, the clamping member 40 comprises notches 46 for engagement with a connecting clamp, hoop or other suitable fixing means such as clamps or wire. At the location of the strap attachment structure, the clamping member 40 comprises two eyes 44 that in this embodiment are integrally formed, e.g. press-formed, however could be provided differently e.g. by soldering a component to the main band body 42.

The eyes 44 provide an attachment location for a hook, thereby allowing the same clamping member 44 to be used with different hook shapes (for instance, with hooks of different length, or different anchor strop attachment such as a hook that is open or an eyelet that is closed). Furthermore, the eyes 44 allow a hook to be provided on only one side of the clamping member, avoiding the supply of double hook clamping members at single or end polytunnels, i.e. polytunnels without and an adjacent polytunnel. In addition, two different strap attachment structures could be provided, for instance for asymmetric polytunnel arrangements, for instance one hook shape suitable for a manually or permanent cover material on one side, and another hook shape suitable for a motorised cover sheet on the other side.

Figure 9 shows a hook 50 constituting a strap attachment structure. The hook 50 provides a multi-hook functionality, here in the form of a dual-hook shape. The hook 50 is a shaped bar of a material of sufficient strength to support anchor ropes or straps tensioned from it. The hook 50 comprises, here, four elbows. One of the elbows is constituted by a joint 52 from which two arms 54a and 56a extend. One of the two arms 54a has one bend 54 constituting a second one of the four elbows. The other of the two arms 56a has two bends 56d and 56 constituting a third and fourth of the four elbows. The joint 52 provides an anchoring point for location in the eye 44.

From the joint 52, the two arms 54a and 56a extend generally in the same first plane, diverging at an angle of about 45 degrees. The first arm 54a comprises a first return elbow 54 bending a portion of the first arm 54a away from the first plane and ending in a distal free end 54b, the shaping of the first return elbow 54 and the distal free end 54b providing a first hook. The second arm 56a comprises a second arm elbow 56d bending a portion of the second arm 56a away from the first plane, a length of the second arm 56a providing an upstand region 56c extending from the first plane and ending in a second return elbow 56 bending a distal portion of the second arm 56a to form a free end 56b extending generally parallel to the first plane. The shaping of the second arm elbow 56d together with the second return elbow 56 and the distal free end 56b provides a second hook. Due to the upstand region 56c, the second hook constituted by the return elbow 56 is spaced further from the first plane than the first hook constituted by the return elbow 54, which is closer to the first plane (here: practically on the first plane).

Figure 10 shows an isometric view of the clamping member 40 provided with two connecting clamps 38 and each of its eyes 44 provided with a hook 50, the joint 52 being located through and in the eye 44. Due to the multiple elbows, the hook 50 needs to be turned at least once when introduced via one of its free ends into the eye 44 before the joint 52 can be located at the eye 44. Thereby, the hook 50 is positioned relatively securely in the eye 44. While retained in the eye 44, the hook 50 may be swivelled, as indicated by an arrow S, about the joint 52, between one position in which the first arm 54a points upward (i.e. is aligned with the extension of the clamping member, perpendicularly to the longitudinal extension of the guttering, towards the free end of the clamping member 40) and another position in which it is the second arm 56a that points upwards (towards the free end of the clamping member 40). The acute angle of the joint 52 between the first arm 54a and the second arm 56a helps to retain the hook 50 in the eye 44 when subjected to a tensioning load pulling the return elbow 54 or 56.

Figures 11 and 12 show different configurations using the clamping member 40 and hook 50. Figures 11 and 12 show the hoop-support end 14 of a support leg 12 with hoops 16 mounted to it. Sheet material 22 is provided, in the manner illustrated in Figure 3, using wing regions 28 folded from a gutter region 24 at fold lines 26 to support the gutter region 24 between two wires 32 (see also Figure 3). The sheet material is secured along the length of the wires 32 with ties 33 extending through some of the apertures 25. The clamping member 40 is mounted to the hoop-support end 14 of the support legs via two connecting clamps 38. The clamping member 40 is provided with two eyes 44 that provide attachment locations for a hook member 50.

The hook member 50 is inserted and held via its joint 52, as described with reference to Figures 9 and 10 above, such that the return elbow 56 points towards the hoop member 16 (i.e., upward) whereas the return elbow 54 extends laterally away. In this configuration, both return elbows 54 and 56 are angled away from the sheet member 22 to reduce the risk of damage thereto. The hook 50 is retained through the eye 44 on the inner, concave side of the clamping member 40, therefore avoiding contact with the sheet member 22. The acute angle between the arms 54a and 56a (see Figure 9) helps to resist an upward pull of the hook member 50.

Figure 12 shows in principle the same components as Figure 11, some reference numerals and elements being omitted for clarity. In Figure 12, the hook 50 is swivelled into a configuration in which the first elbow 54 points into the direction of the support hoop 16, the second elbow 56 being angled away so as to avoid interference with anchor ropes or straps and avoiding contact with the sheet member 22.

The arrangement of Figures 11 and 12 is reversible in that the hook 50 may be interchanged between a shorter-hook configuration (Figure 12) and a longer-hook configuration (Figure 11) in a reversible manner. The hook 50 may also be replaced with a different hook structure if desired. Alternatively, the hook may comprise a hook end with open hook gap and an eye with closed loop, or similar variants of different attachment configurations. This improves the versatility of the gutter-fastening member. By avoiding the need for perforating the sheet material in the gutter region 24, the clamping member 40 may be affixed with a relatively larger clamping force.

Likewise, depending on the tightness of the engagement with the gutter material, the gutter arrangement allows a small degree of re-positioning of the sheet material 22 by pulling, without thereby risking a tearing or enlarging of a perforation point. As may be imagined, when installing several tens of meters of guttering made from pliable sheet material, some portions of material along the length of an installation may otherwise wrinkle or bulge if tightly affixed via perforating fixing means. It will be understood that the gutter-fastening members may be installed and tightened gradually depending on the installation process, number and length of polytunnel installations, and other local requirements. For instance, a length of gutter material may be rolled out and installed without gutter-fastening members installed, then gutter-fastening members may be loosely installed in a manner limiting vertical removal of the guttering material but still allowing for position-adjusting of the guttering material and tensioning, and finally, once the length of guttering is shaped and tensioned as desired, the gutter-fastening members may be tightened to provide a better wind load resistance.

The connecting clamps 38 are exemplary designs and other attachment means may be used to secure the clamping member to the leg 14 and/or the hoop member 16. The connecting clamp hoops may be shaped according to the cross-section of the hoop-supporting end 14 or hoop members 16 to which they are intended to be mounted. This increases the versatility, because the same design of clamping member may be used with different forms of hoop member 16 and with different strap attachment structures.

While the legs are illustrated as bifurcated "Y" shape, and therefore the clamping member is shaped as a curved band so as to provide a complementary shape, the clamping member may have a different shape to match different leg designs.

Figures 13 to 19 show another aspect related to the gutter arrangement. The end of the guttering 20 is provided with a gutter end plate 64. The gutter end plate 64 may be of any suitable material such as metal material, plastics material or composite material.

When used with a sheet material such as polypropylene sheet material 22, it is practical to clamp folded material flaps 29a, 29b, 29c at the end of the length of sheet material and mount these via an end plate arrangement comprising an end bracket 60 and an end plate 64. As shown herein, the material flaps 29a-c are folded outward, although they might also be folded inward, a bracket component similar to the end bracket 60 compressing the flaps against the end plate 64 in a fluid tight manner. Conveniently, the end bracket 60 is a generally arched shape conforming to the gutter shape, which may be designed to match the curvature of the free arms 15 of a bifurcated hoop-supporting end 14 of a leg 12. The end bracket 60 comprises a plurality of bracket holes 62 corresponding in position with end plate holes 66a, 66b, 66c. The bracket holes 62 may be aligned with the end plate holes 66a,b,c to receive a bolt-and-nut arrangement, although other suitable connecting means such as clamps may be used. By tightening the end plate 64 against the end bracket 60, the flaps 29a,b,c of sheet material can be tightly connected between them and thereby with the end plate 64. As part of the end plate arrangement, fluid-tight seal components in the form of pads and/or adhesive may be used. However, using suitable gutter material the gutter material itself may provide a seal function that is sufficiently reliable for practical purposes. The gutter sheet may be provided with a run-off hole 35 near the end plate, however this is not necessarily the case in all embodiments. For instance, one or more run-off holes may be located at suitable locations along the length extension of the gutter.

The end plate 64 may be part of, and/or affixed to, a support leg 12. The support leg 12 may be of the same type as the other support legs 12, or may be an alternative design for the end of a polytunnel 10a, for instance if it is desired for guttering to extend beyond a polytunnel. In one configuration, the arms 15 of the support leg 12, and/or portions of the hoop members 16, comprise a plurality of holes 70a, 70b, 70c for receiving a bolt 72a, 72b, 72c connecting with the end plate 64. By adjusting the relative position of the elongate bolts 72a,b,c and that of the nuts used to clamp the end plate 64 and the end bracket 62 relative to each other, the spacing between the end plate 64 and the support leg 12 may be gradually adjusted (see also the description below of Figures 19 and 21).

In another form of end plate arrangement, illustrated in Figures 18 and 19, the holes 70a,b,c to be formed in the leg 12 are avoided. Instead, the bolts 72a,b,c,d are affixed to or integrally mounted with a clamping plate 82a,b,c,d of a mounting ring 80a,b,c,d for mounting to a leg 12. Each of a plurality of (here: four) mounting rings 80a,b,c,d can be tightened via respective threaded bolt-and-nuts 84a,b,c,d against the clamping plate 82a,b,c,d to tighten the clamping plate 64 to a leg 12, conveniently via the arms 15, although other connection points may be used in other embodiments. Independently of the clamping plates 82a,b,c,d, pairs of tightening nuts 74a,b,c,d are threadedly positionable along a length of a shaft of the bolts 72a,b,c,d. The sheet material 22 is held between the end plate 64 and end bracket 60 which are held together by, or sandwiched between, a pair of tightening nuts 74a,b,c,d. As will be appreciated from Figure 19, by moving the pair of tightening nuts 74a,b,c,d closer to the clamping plates 82a,b,c,d, the sheet material 22 clamped between the end plate 64 and the end bracket 60 may be tensioned, and vice versa, tension may be reduced by movement in the opposite direction, as indicated by an arrow D in Figure 19. Thereby, the tension of the guttering can be adjusted by adjusting the pairs of tightening nuts 74a,b,c,d. It will be appreciated that the tightening nuts are a practical example and that other forms of length adjustment may be used for adjusting the tension of the guttering.

Figures 20 and 21 show another form of end plate arrangement similar to that of Figures 18 and 19, using and end plate 64 and corresponding end bracket 60 to be mounted to a leg 12 via bolts 72a-d. Instead of pairs of clamping plates (see clamping plates 82a-d and 84a-d in Figure 19), the connection may be provided by a mounting hoops 86a,b,c,d comprising two free arms carrying a clamping band 88a,b,c,d. Conveniently, the free arms are of threaded form, the clamping bands being secured thereto via corresponding nuts, to allow a leg arm 15 to be clamped between the two free arms of a hoop and the clamping band. Compared to the Figure 18 embodiment, the Figure 20 embodiment avoids the need for two separate bolts 84 to connect two clamping plates. With regard to repositioning the end plate 64 relative to a leg, the embodiment of Figures 20 and 21 is used in similar manner to that of Figures 18 and 19, for instance using pairs of tightening nuts 74a,b,c,d, and so the description thereof is not repeated.

It will be understood that the embodiments of Figures 18 to 21 are examples, and that the end plate arrangement may be connected to a leg in another suitable manner.

The elongate bolts 72a,b,c,d, as illustrated in Figures 19 and 21, may have any suitable length although will for practical purposes have a length between 2 and 10 centimetres. Thereby, the tension of the guttering may be adjusted, and it is believed that an adjustment in the region of a few centimetres may assist with tensioning guttering of several tens of metres. The tensioning is, in this regard, intended to assist with retaining the shape of the guttering while under water loads. By tensioning the guttering, the likelihood is reduced of bulges or folds forming which might otherwise impede water runoff. As a consequence, it is believed that the tensioning arrangement results in less steep gutter runoff angles being required. In turn, the arrangement allows guttering to be installed over longer sections, of several tens of metres than would otherwise be the case. The effect is further improved by combining the end plate tensioning concept with clamping members of the type described with reference to Figures 3 to 12, avoiding a need for perforating the sheet material 22 in the gutter region 24, which enables a tensioning movement longitudinally across a leg member, while providing a sheet-shaping member.

The sheet-shaping functionality of the clamping members is conveniently combined with the strap attachment structure such as the hooks 34, 34a, 34b or a reconfigurable embodiment such as the hook 50, which allows anchoring ropes or straps to be anchored to the leg 12, via the clamping plate and the connecting clamps 38. By locating the strap attachment structures inward of the clamping member, i.e. within the footprint of the clamping member, the anchoring ropes or straps under tension are more likely to avoid contact with the sheet material 22, reducing the likelihood of damage to the sheet material 22 of the gutter. Likewise, if a retro-fit installation is intended for instance to motorise the sheet operation, requiring a different strap attachment structure, then this may be achieved using a gutter-fastening member such as that described in Figures 7 to 12 by simply exchanging or altering an existing hook configuration, without necessarily requiring a change of the gutter-fastening member.

The aspects of the invention facilitate the installation of relatively low-cost guttering (low cost compared to formed metal guttering) that is also suitable for relatively long polytunnels, and potentially for any practical length of polytunnel. The sheet material requires practically no forming machinery on site at the time of installation, instead the bracket components and one or more rolls of gutter sheet material can be provided as prefabricated components, in the form a roll or reel of gutter sheet material, ready for assembly. The system offers versatility in respect of anchoring rope spacing, hoop member design, and run-off angles, which is believed to result in wider adoption of guttering for polytunnel installations where this was previously difficult to justify commercially.

The prospect of rain water collection provides an improvement in that it allows water so collected to be reintroduced in a reliable manner into the farming process, reducing the demand for fresh water. In this manner, a more readily available gutter design is believed to provide a significant environmental benefit.

While the system has been described using polypropylene sheet as gutter material, other materials may be used, including non-plastic material. The gutter material may not necessarily be provided as a pliable or rollable material. In this regard, the clamping system described herein is believed to be suitable also for non-pliable gutter sections, including those made from light weight materials.

The description above is exemplary and the scope of the invention is defined by the claims appended hereto.

Claims

CLAIMS: 1. A gutter arrangement for a polytunnel structure, to be mounted along a length extension of the polytunnel structure, the polytunnel structure being of the type comprising sheet-support hoops on pairs of legs to support a cover member retained by anchoring straps, the gutter arrangement comprising a gutter-fastening member to restrict lifting of a length of gutter material from the leg, the gutter-fastening member comprising a strap attachment structure for attachment of an anchoring strap.
2. The gutter arrangement according to claim 1, wherein the strap attachment structure is fixed to the gutter-fastening member.
3. The gutter arrangement according to claim 1, wherein the strap attachment structure is repositionably attached to the gutter-fastening member.
4. The gutter arrangement according to any one of the preceding claims, wherein the gutter-fastening member is attachable, in use, to the leg at a position above the gutter material.
5. The gutter arrangement according to any one of the preceding claims, wherein the gutter-fastening member comprises an arcuate profile comprising an outer, convex, surface and an inner, concave, surface, the strap attachment structure being located on the inner, concave surface.
6. The gutter arrangement according to claim 4 or 5, wherein the strap attachment structure is positionable in one of at least two positions on the gutter-fastening member, each of the at least two positions providing a different spacing of the strap attachment structure from the gutter-fastening member.
7. The gutter arrangement according to any one of the preceding claims, wherein the strap attachment structure comprises two hook arms extending from a connection point with the gutter-fastening member, one of the two hook arms being longer than the other of the two hook arms.
8. The gutter arrangement according to any one of the preceding claims, comprising longitudinally extending support structures supporting the length of gutter material, the longitudinally extending support structures extending across a series of legs.
9. The gutter arrangement according to any one of the preceding claims, comprising a gutter formed from pliable sheet material.
10. The gutter arrangement according to claim 8, wherein the sheet material comprises polypropylene.
11. The gutter arrangement according to any one of claims 8 to 10, wherein the sheet material comprises fold lines extending along the extension of the sheet material.
12. The gutter arrangement according to any one of claims 8 to 11, wherein the sheet material comprises pre-formed apertures spaced apart and extending along the extension of the sheet material.
13. The gutter arrangement according to any one of the preceding claims, comprising an end plate arrangement comprising a gutter end plate and a leg connector for connecting the end plate to a leg, the leg connector comprising an adjustable spacer allowing a distance to be altered between the gutter end plate and the leg.
14. A gutter arrangement for a polytunnel structure, the polytunnel structure being of the type comprising sheet-support hoops carried on pairs of legs to support a cover member retained by anchoring straps, the gutter arrangement comprising a length of gutter material extending across a series of legs, and further comprising an end plate arrangement comprising a gutter end plate and a leg connector for connecting the end plate to a leg, the leg connector comprising an adjustable spacer allowing a distance to be altered between the gutter end plate and the leg.
15. The gutter arrangement according to claim 13 or 14, wherein the leg connector is constituted by one or more bolts.
16. The gutter arrangement according to claim 13 or 15, wherein the gutter end plate is connected to the leg connector via a plurality of bolts in threaded engagement with the gutter end plate.
17. The gutter arrangement according to any one of claims 13 to 16, comprising an arrangement of brackets for attachment to the leg, the brackets affixed to the end plate via one or more adjustable spacers.
18. The gutter arrangement according to any one of claims 13 to 17, wherein the gutter end plate is fixed to a gutter end bracket, the gutter end plate and the gutter end bracket comprising abutment structures to compress portions of gutter sheet material between them.
19. The gutter arrangement according to any one of claims 13 to 18, wherein the leg connector is connected to the leg via a portion of a sheet-support hoop.
20. The gutter arrangement according to claim 19, wherein the portion of the sheet-support hoop is mounted on the leg.
21. The gutter arrangement according to any one of claims 13 to 18, wherein the leg is not carrying a sheet-support hoop.