GB2624769A

GB2624769A - Palidsade fence rail with improved form

Info

Publication number: GB2624769A
Application number: GB2315312.5A
Authority: GB
Inventors: Anilkumar Kotecha Vinesh; Barry Mitchell Andrew
Original assignee: First Fence Ltd
Current assignee: First Fence Ltd
Priority date: 2022-03-04
Filing date: 2022-03-31
Publication date: 2024-05-29
Also published as: GB2611130B; GB202204579D0; GB2624529B; GB2612865B; GB2616417A; GB202203032D0; GB2616417B; GB2611128B; GB2611128A; GB2624529A; GB2612865A; GB202204665D0; GB2611130A; DE102023105334A1; GB202205547D0; DE102023105333A1; GB2621486A

Abstract

The rail 10 comprises an elongate sheet member having apertures for securing to posts and apertures along the length for securing pales. The cross section comprises a main face 20 in which the apertures are located. A lower face which extends from the main face, which is angled perpendicularly or possibly between 95-110 degrees to the main face. An upper face 40, which includes a protrusion 42, is angled away from the main face and a rear face 50 angled with respect to the main face and protruding away from the main face and has a second end. The rail may be galvanised and cold rolled. Also claimed is a palisade fence section comprising pales fastened to two of the rails. The pales may be fastened by a number of bolts which wear away under tension to prevent the bolts reengaging the pale. The bolts may have conical, frustroconical or shaped bolt heads. Also claimed is a method of constructing a palisade fence with the rails. Also claimed is a kit.

Description

Palisade fence rail with improved form Palisade fences are widely used for security applications were a relatively high strong fences required. The present invention relates to a palisade fence rail with improved form and in particular with increased durability.

Background

Palisade fences are typically supplied as a kit of parts comprising posts, between to which pales are placed, simply to rails an upper and a lower horizontal row. Vertically between the rails are placed a plurality of pales, to form of fence panel between the posts. Palisade fences are typically erected in the open air and are usually coated and/or galvanised to reduce corrosion. The pales are typically secured to the rails by means of fasteners, usually in the form of nuts and bolts. Wherein the nuts provided may comprise shearing nuts, which grips a bolt and then notches off at a given point leaving behind a securing collar on the bolt. These features are to make detaching the fastener from the fence more difficult. However, because of the snap feature the fasteners expose unprotected metal and the collars themselves are relatively small, this is done purposely so that they are having to grip, such as with a spanner. This combination of features leads, over time, to these fasteners corroding, particularly in exposed areas such as sea coasts. This means that the integrity of the fence can be diminished due to this corrosion, typically observable on, or from the rear of the fence, so may not be evident to the casual viewer.

An example of a rail relevant to the above characteristics is disclosed in GB2372759B. Which discloses a palisade fence with a sloped face with protrusions to help deter intruders, wherein the sloped face would cover the aforementioned fasteners. A similar profile can be found in EP1366254B1.

There is a need for a palisade fence with improved durability without increasing costs, which is effectively improving a basic civil engineering construction. In the case of the present invention, the design is improved by making adjustments to the profile of the rail as will be set out in detail below. This way the design can be improved without the need for additional materials, and therefore there should be little to no additional costs. From the above there is also a need for this improved design to provide improved protection to the fasteners, as well as the surface of the rail, to help prevent wear and corrosion.

Summary

The present invention provides: a rail for use in a palisade fence. Wherein the rails are coupled to a plurality of fence pales to form a fence panel, then the ends of the rails are configured to be attached between fence posts, for providing support to the fence panel, by means of suitable fasteners. Wherein the plurality of pales is also attached to the rail, by means of fasteners. The rail itself comprising an elongate sheet steel member having at its ends apertures, or other suitable features, for securing to the posts, and along its length apertures for receiving the fasteners for securing pales to the rail; the rail having a cross section perpendicular to the elongate axis, the cross-section comprising a main face in which the apertures are located a lower face perpendicular to, or angled away from, the main face and having an upper face angled to the main face, extending from the opposite side of the main face than the lower face. This upper face may optionally comprise protrusions, to act as a deterrent. And a rear face angled with respect to the main face, protruding from the end of the upper or lower face remote from the main face, in a direction away from the main face.

As compared to the closest prior art, GB2372759B, the present invention differs in that the rear face is angled with respect to the main face, and the addition of protrudes away from main face. This more efficiently shelters the rear of the main face, the face of the rail to which the snap off fasteners is conventionally attached. In comparison the prior art discloses that the rear face is parallel to the main face.

Designs of this type, as shown in the cited prior art, have had no changes to this configuration in the last 20 years even in the face of the known problem.

Preferably, in the present invention the angle between the vertical (wherein the main face provides the relevant reference) and the first or second end of the rail, defined by the end of the rear face of the cross section is between 50° and 70°. By using angled end portions, when compared to the parallel ends of the prior art, the claimed rails provide better screening, to protect the inner surface of the rail. This is to say that the more swept out end portions can deflect precipitation and other potential eroding factors, such as sand pickup by the wind, away from the rail over a wider range of angles, thereby providing improved protection. This preferred angle range also serves to reduce access to fasteners coupled to the main face of the rail, as any intruders attempting to tamper with the fence, by trying to release the fasteners, will have more difficulty try to reach them under the swept-out end portions, these ends may also make it harder for the intruder to rotate tools, such as a spanner, once the fastener is reached, due to the tool needing to be positioned at an angle relative to the main face of the rail. It should be noted that the other end of the rail defined by the upper or lower face, whichever is not connected to the rear face, may have a similar angle relative to the vertical, again to provide protection from the environment and to restrict access to the fasteners.

It is noted that the front of the fasteners, typically in the form of a bolt, are conventionally protected by the rail member, this is to say that the shank, or shaft, of the fastener is usually cover by the profile of the rail, thereby protecting it from intruders and the surrounding environment. In the case of the claimed invention this protection is provided by the upper surface and end portions of the rail, which helps provide protection from the weather, and other environmental corrosion factors, by using the protected surfaces of the rail to screening the bolts and the nuts, or securing collar, fastened to said bolts. It is also noted the heads of the bolts are usually exposed and so are coated, or galvanised, to protect them from corrosion, it is also noted that the searing surface of said bolt heads, which are broader than the aperture that received the fastener may provide some protection to the inner surface by preventing environmental corrosion factors from reaching the apertures within the rail, however in some cases the profile of the rail may also be shaped or angled to protect the bolt heads, by again screening the bolt head from environmental factors, though this effect may also be achieved by the pales couple to the rail, wherein the bolt head is recessed into either the pale's or the rail's surface. It is noted that while protecting the fasteners, the claimed rail profile still enables sufficient access for construction of a palisade fence. In particular, while the fence panel is being constructed, the rails and pales may be placed along the ground, or other flat surface to allow the user to access the fasteners from the direction facing the lower end portion of the rail, to allow for easy construction, then once erected the direction used to access the fasteners would be facing downwards, towards the ground, and would now be covered by the lower surfaces of the rail, with the other directions being at least partially covered by the upper face and the swept-out end portions of the rail, making it more difficult to access the fasteners once the fence is constructed.

It is also noted that a more preferred range for the angle between the vertical main face and the end portions is 55° to 65°. As we ideally want angles to be large to provide better coverage of the rails inner surface, thereby providing more protection.

However, angles above the disclosed range would provide improved protection, however they would also hinder access to the inner surface to a point where the user may be unable to access the fasteners sufficiently to construct the fence panels. Therefore, the preferred range provides a compromise where improved protection, compared to the prior art, is provided, while also allow enough access to the inner surfaces of the rail to construct the fence with relative ease. However as noted we do want to hinder access to the fasteners somewhat, as this will help to hinder intruders attempting to remove the fasteners from the constructed fence.

For reference it is noted that in this technical field small changes in form can be significant, in that they may affect requirements for providing sufficient security and for the volume of product produced. An example of this can be found when comparing the pale profile in compared to that shown in W09533113A1 and GB2573388B. In particular the Figures 6, 8, 10 and 11 of W09533113A1, provides information on how the angle, and thickness, of the profile of a fence pale made of a sheet material effect the force that can be withstood, before the pale deforms. This same information can be applied to the sheet material used to form the rail. Wherein the user wants large force deflection/absorption to provide improved security to the site the fence is erected within, or around. However, as noted in these documents the benefits for increasing the thickness of the sheet material, or the angles of the profile diminish as it increases, in particular in regards to the angles it is noted that the benefits diminish rapidly as the angle approaches 90°, therefore a range of 50°70° was likely preferable. It should also be noted that increasing the thickness of the sheet material used to form the rail may also increase the production cost, as the fence requires more material and greater force to shape, which would reduce the rate of production for the rails.

In some embodiments the lower face, or end portion, may be folded over, so that the inner surface of the lower face is parallel to, or even touching the inner surface of the main face. This is done to provide protection to the inner surfaces, however the space between the inner surfaces may cause additional problems as any water which reaches the inner surface, likely through the apertures in the main surface, may become trapped within the fold, between the main and lower surface, and thereby cause more corrosion to these surfaces. In the presented rail the lower face may be angled away from to the main face, this stops water gathering below the apertures in proximity to the fasteners and so reduces corrosion. The angle is preferably between 95° and 1100 (61, 10A) as this retains substantial rigidity to withstand forces against the fence, provides some screening to the rails inner surface, whilst also stopping the pooling of water by allow water to run-off the sloped lower surface.

It is also noted that the present invention may include one or more protrusions within the upper surface of the rail. In particular the upper surface may include pointed protrusions that stand vertically, relative to the plane of the upper surface. Such protrusions would be positioned in between the apertures used to receive the pales and/or posts, so that when constructed the protrusions would be positioned on the portions of the rail, between the affixed posts/pales. Wherein the pointed protrusion may act as a deterrent to intrude trying to grip, or step on the rail, in the same manner as the points on the top of the palisade fence pales. However, it is noted that it may be preferable to have such protrusions be angled relative to the upper face of the rail, rather than perpendicular. In particular, if the protrusion was at an angle below 90°, such as an angle in the range 60°-70°, as this way less of the inner surface of the protrusion is exposed to the environment, which may help to reduce the risk of corrosion to the protrusion itself, while still being sufficiently pointed/angled to act as a deterrent. Alternatively, the protrusion may have an angle larger than 90°, to help prevent corrosion to the inner surface of the rail, specifically the inner surface of the main face. As this larger angle may mean that any water that runs down the protrusion, into the gap/aperture formed when making the protrusion with the sheet material of the rail, is directed away from the inner surface of the rail. Though it is noted that these larger angles would expose the inner surface of the protrusion, thereby increasing the risk of corrosion to the protrusion itself.

It is also noted that a similar protrusion may be formed, when making the apertures for receiving the fasteners. In particular these protrusions may face inwards and would have a large angle, over 90°, relative to the main face of the rail, so that the protrusion may be flatten by the fastener, once fastened into place. The purpose of these inward protrusions is to further protect the inner surface of the rail, as such protrusions would help to direct any water that enters to aperture away from the rails inner surface, and when flattened the protrusion would still cover a portion of the inner surface, again protecting it from water and other environmental corrosive factors.

In regards to manufacturing the above-mentioned rails it is noted that that generally such rails are preferable made with a strong material, to provide strength and resist impacts. However, it should be noted that the rail may also need to be made of a material that allow resilient deformation, in addition to providing strength, such deformation can be used to better absorb the force of an impact, and during construction of the fence may help to better align the rail and pales, especially in adverse environmental conditions make it difficult to arrange the rails of the fence parallel to one another, and the pales perpendicular to the rails, such as an uneven surface. For this purpose, it is preferable for the rails to be made from a material, such as mild steel. As mild steel, being made of steel is both strong and generally weather resistant, but provides the additional benefit of being flexible enough to resiliently deform when the fastener is tightened, to help align the pale during construction of the palisade fence.

Then there is a need to consider the thickness of the material used to form the rail. In regards to the present invention, the thickness needs to be thin enough to allow material to bend when forming the rail, and to allow the rail to resiliently deform slightly when the fence is being constructed, while also providing sufficient strength. It is noted that if the material is too thick it would not be able to provide the necessary flexibility for resilient deformation, and may also be more difficult to shape, as more force would be required to bend the material. Based on the British standards set out in BS1722-12:2006 table 6, regarding the thickness of different pale designs, it is noted that for security use the standard for the deformable D-section is 3mm, while the W-section is 2mm. Therefore, for the present invention a thickness between 1mm and 3mm would be preferable. As the rail is required to have similar properties to that of the pale, it may be reasonable to assume similar materials can be used. Therefore, of these thickness 2-4mm may be the most preferable as it is the easiest to shape and provides the highest flexibility, while still providing the rail with sufficient strength to endure impacts. The reason for this is that this range provide a rail with the optimal thickness, to be deformable, easy to fasten while still being relatively strong. For example, if the fence was made thinner than this, it would not have sufficient area to grip the fastener, additionally if said fastener is over tightened, there is a risk of the fastener damaging the rail, due to the thin surface bending, or breaking, under the additional tension. It is also noted that the thinner rails would also be easier to damage, within impacts to the rail's surface, resulting in the fence panel bending and possibly breaking. Additionally, it is preferable for the rail to be thicker than the affixed pales, as each rail needs to support multiple pales. Alternatively, if the rail is made too thick, it may be harder to deform, due to the additional force required to deform the extra material. Additionally, the user may require larger fastener to secure the pale into place, which due to the increase grip of the thicker rail, may be harder to secure manually. Thereby meaning that a thinner pale would be too weak to provide security, while a thicker pale may be harder to shape when forming the rail. Therefore, as mentioned it is preferable to have a rail with a thickness between 1 and 4 mm as these thicknesses provide sufficient grip and strength, while still be resiliently deformable.

Additionally, the use of mild steel may allow the rails to be manufactured using a cold rolling process. It is noted that generally, it is preferable for the palisade fence rail to be made from a cold rolling process, that a hot rolling process, and therefore must be made from a suitable material that can be shape via a cold rolling process. The reason for this preference is that, when forming the rail using a hot rolling process, internal stresses are formed within the material as the heated metal/alloy undergoes the hot rolling process, due to the heated metal/alloy being more flexible than the same material when it is cold, resulting in the formation of weak points in the areas affected by these internal stresses. However, when using a cold rolling process such internal stresses do not form, and therefore the pale produce by the cold rolling process should not have the same weak points forming, and is therefore generally stronger. As a result, the cold rolling process provide a better standard of rails.

It is also noted that the rail may be powder coated, before assembling the fence, to help protect the rail's surfaces from the surrounding environment. It is also noted that a powder coating would provide better protection when compared to a painted pale.

An alternative to the powder coating may be to galvanise the surface of the rail. Additionally, the galvanised surface may be preferred over a layer of paint or a powder coating, as the galvanised surface is flexible and therefore less likely to crack, or break, as the surface of the rail is put under tension when fastened to the plurality of pales. Thereby providing improved protect as such crack is the powder coating would leave portions of the rails surface exposed to the environment.

It is noted that the rails of the present invention may be presented as part of a kit of parts. Wherein the kit of parts provides all of the necessary features to construct one or more fence panels as described above. Such a kit may include: at least one rail as described in the present invention, preferably two per panel for better support, a plurality of pales to be affixed to the rails, and a plurality of fasteners suitable for securing the pales to the rails, by inserting the fastener through an aperture within the pale and a respective aperture within the rail.

It is noted in the preferred embodiment the fastener would be in the form of nuts and bolts, as they are relatively easy to use and produce, and provide sufficient strength for security purposes. Wherein the threaded shank of the bolt is passed through an aperture in one of the pales, and through a respective aperture within the main face of the rail. Once in place the nut can be fastened to the shank of the bolt and tighten in order to grip the rail and pale between the nut and the bolt head. It is noted that nuts and bolts can include additional security features to make it more difficult for an intruder to remove the fastener. Such features include the aforementioned shear nut, wherein the gripping portion of the nut can be sheared off by over tightening the nut, leaving behind a thin collar, which is sufficiently strong to hold the fence together, but due to its small size and curved edges, is much harder to remove compared to a regular nut. Similarly, the bolt may comprise a sloped bolt head, which may have a conical, pyramidal, frustoconical shape, as the curved surface of the bolt head would again be harder to grip and remove with conventional tools. Additionally, the bolt may comprise a shearing thread, that is to say when in use, the thread on the shank of the plurality bolts is configured to wear away under tension, to prevent the bolts re-engaging the pale, and/or rail, as this will again make it more difficult to remove the fastener from the fence.

Drawings The present invention is illustrated by means of the following diagrams in which Figure 1, shows a cross-section the rail (10) having a cross section perpendicular to the elongate axis, comprising a main face (20), upper face (40), and end portions (32,52), comprising a lower face (30) and rear face (50), and includes the optional protrusion (42).

Figure 2, shows the same cross-section as figure 1, indicating the preferred angles between the different faces of the rail, and for the protrusion.

Figure 3, shows the same cross-section as figure 1, indicating the preferred angle for the end portions of the rail relative to the vertical.

Figure 4, shows a portion of the outer surface of the rail.

Specific description

Figure 1 shows a cross section of the preferred embodiment of the present invention. In particular the depicted rail 10 comprises a cross section perpendicular to the elongate axis of the rail 10, comprising a main face 20, upper face 40, end portions 32,52 and rear face 50, it is also noted that the depicted rail comprises the additional optional features of the lower face 30 and includes the optional protrusion 42.

Wherein the main face 20 defines the vertical axis if the rail, and comprises a plurality of apertures spaced along the length of the rail. Wherein the apertures are configured to receive a fastener that is used to secure a plurality of fence pales to the disclosed rail 10. The ends 32, 52 of the rails may also comprise additional apertures, or features, for securing each end of the rails to a respective post, thereby securing the panels of the palisade fence in between said posts. It should be noted that in some cases the apertures, or features at the end of the rail 10 may be coupled together, with a suitable fastener to form longer rails, if necessary, this may be the case if an adverse environment has meant that one or more posts could not be placed around the perimeter of the area to be protected.

The rail 10 then comprises an upper surface 40 that is angled relative to the main face 20. The upper surface 40 provides some additional protection to the rail 10. In particular the sloped surface provided by the upper face 40 may be more difficult for an intruder to grip, and/or step onto, when trying to climb the fence. Further, the upper face 40 is preferably angled so that it extends rearward, from the perspective outside of the fence, thereby proving cover to the inner surface of both the upper 40 face, and the main face 20, which may help reduce the risk of corrosion to the rail 10, and the fasteners secured to the rail 10. Additionally, the sloped surface will help any water, in particular rain, or other corrosive materials, to run off the surface of the rail 10, and further the sloped surface directs the flow of the water away from the inner surface, thereby helping to further reduce the risk of corrosion. Further, as shown in figure 1, the upper face 40 may include a plurality of protrusions 42 along its length. These protrusions 42 would be placed along the surface of the upper face 40, so that when the fence is constructed the protrusions 42 are positioned between the fence's pales. These protrusions may act as a deterrent to intruders trying to climb the fence, similar to the points at the top of the palisade fence pales, as the protrusion can stop the intruder grabbing, or stepping onto the rails.

The rail 10 also comprises a rear face 50 that extends from the end of the upper face 40 that is remote from the main face 20. Wherein the rear face 50 extends downwards, relative to the vertical, defined by the plane of the main face 20. It is noted that the rear face 50 is angled relative to the main face 20, so that the main face 20 and the rear face 50 are non-parallel. The purpose of the rear face 50 is to prove protection to the inner surface of the rail, by screening the inner surface of the rail from the weather and other factors that may cause corrosion to the rail 10. It is noted that the rear face 50 is preferably angled away from the main face 20, this way the swept out rear face 50 provides a sloped surface that can direct water, and other material on the rail 10, away from the rail 10, specifically away from the inner surface. Additionally, the angled rear face 50 may provide improve protection compared to a face that is parallel to the main face 20, as the sloped surface can screen a wider range of incidence angles, that is to say the angled wall may be able to intercept water, in particular rain and other precipitation, from a wider range of trajectories/angles. The angled rear face 50 may also help hinder an intruder's attempts to vandalise the palisade fence, by making it more difficult to reach the inner surface, to reach and unfasten the fasteners supporting the fence's pales, as the intruder would need to reach around the angled slope of the rear wall 50.

The rail 10 may also comprise a lower face 30 couple to the end of the main face 20, remote from the upper face 40. Wherein the lower face 30 extends inwards away from the main face 20. The purpose of this face, similar to the rear face 50 is to protect the inner surface of the rail, by acting as a screen which can deflect water, and other materials that may cause corrosion, away from the rail 10. It preferable that this lower face be angled relative to the main face 20, in particular the lower face should be at an angle of 90° or more relative to inner surface of the main face. If the lower face 30 is at a smaller angle there is a risk that water, or other material, may become trapped within the space between the main face 20 and the lower face 30, especially when the water passes through the aperture of the main face 20. This trapped material will increase the chance that the rail 10 corrodes. Therefore, it is preferable to have the lower face 30 be angled, at least perpendicular relative to the main face 20, this way any water that enters the space between the inner surfaces of the main face and the lower face 30 may run-off the lower face 30. Additionally, like with the rear face 50, and upper face 40, the lower face 30 may help hinders an intruder's access to the fasteners securing the fence, as the lower face 50 acts as a physical barrier blocking access to the fasteners, making it harder for an intruder to vandalise the fence, or remove the fence's pale.

It is noted that the depicted rail 10 is preferably made from a strong sheet material, such as mild steel, which can be shaped into the desired profile using a rolling process, in particular a cool rolling process. It is noted that a sheet material is preferable as they can be used to produce a large volume of rails in a relatively short amount of time. Mild steel, or similar metals/alloy materials, are preferable as they provide strength, even when the material is thin, and are typically malleable allowing them to be shaped easily. It is noted that steel is more preferable as steel is usually resistant to corrosion, especially from water. It is noted that the rolling process is preferable as it again produces a large volume of product in a short amount of time. It is noted that a cool rolling process is preferred over a hot rolling process, as the heated portions of the sheet material may create weak points after they cool due to the difference in tensile strength between the cool and heated metal.

Figure 2 depicts examples of the preferred angles for the rail profile. In the depicted example the first angle (81) between the main face 20 and lower face 30 is 90°. It is noted that for the first angle (91) the angle should be no less than 90°, for if the angle was smaller then water and other mater may be trapped between the lower face 30 and the main face 20, as the lower face 30 would be angled towards the main face 20, that is to say the end point 32 of the lower face 30 would be brought closer to the inner surface of the main face. Angles larger than 90°, on the other hand, slopes the lower face 30 away from the main face 20, creating a slope where water and other materials can run-off the lower face 30 and are directed away from the main face 20. However, using these larger angles would reduce the amount of screening the lower face 30 provides, as the inner surface of the main face would be more exposed to the surroundings. Therefore, the angle of 90° is the most preferable as it provides the most amount of screening to the rail's inner surface, and does not trap material between the lower face 30 and main face 20. It is noted that this screening also protects the fasteners supporting the fence by making it more difficult for an intruder to reach the inner surface of the rail.

The second angle (82) depicts the angle between the main face 20 and upper face 40. It is preferably that the upper face 40 be angled relative to the main face 20, rather than perpendicular, as the slopped upper face 40 will allow water and other materials to run-off the upper face 40. For if the upper face 40 was perpendicular to the main face materials, like water could gather, or pool, on the surface of the upper face, increase the risk of corrosion to the rail 10. It is also noted that the second angle (82) would preferably be more than 90°, for if the angle was 90° or less an intruder may be able to us the rail 10 as a step to climb over the fence. However, with a larger angle, the slope of the upper face would be angled towards the front side of the fence, outside the protected area, and therefore would be harder to climb from outside the fence. It is also note that the upper face 40 also provides protection to the inner surface of the rail. However, like the lower face 30, as the second angle (02) increases, moving the upper face 40 to be more parallel with the main face 20, the amount of protection provided by the upper face diminishes. Therefore, an angle of 120° is preferable as it slopes the upper face 40 towards the main face 20, allowing material to run off, and making it difficult for an intruder to climb the rail 10, while also allowing the upper face 40 to provide a sufficient amount of screening to the rail's inner surface, to help prevent corrosion to the rail 10 and the fasteners coupled to the rail 10.

The third angle (83) shows the angle between the upper face 40 and the rear face 50. In the depicted example the third angle (Oa) is 90°, however it is noted that for the rear face 50 the important factor is that the rear face 50 is sloped away from the main face 20. This way water, and other materials will run-off the sloped surface of the rear face 50, and be directed away from the rail's inner surface. Additionally, by not having the rear face 50 parallel to the main face 20, the rear face 50 can better screen the inner surface as the sloped rear face 50 will block precipitation, such as rain, from a larger range of angles relative to the main face 20. Further the sloped rear face 50 will make it harder for an intruder outside the fence to reach the inner surface of the rail, to release the fence fasteners, as the angled rear face 50 increases the distance between the rail's end point 52 and the main face 20, which the intruder would need to reach across to access the fasteners. It is also noted that if the second angle (32) was changed, the third angle (33) would need a corresponding change so that the rear face 50 remains at the same angle relative to the main face 20, as the chosen angle provides the best compromise between shielding the inner surface, while increasing the gap between the main face 20 and the end point 52 of the rear face 50.

Finally, Figure 2 also depicts a preferred angle for the protrusion 42 on the upper face 40. it is noted that the protrusion 42 is design to point out of the upper face 40 to create a point that help prevent an intruder grabbing or stepping onto the rail 10, while trying to climb the fence. An example of the preferred embodiment of the protrusion 42 is depicted in Figure 4, wherein the protrusion 42 is formed by cutting into the surface of the upper face 40, then folding a portion of cut section of the upper face 40 upward, away from the inner surface of the rail, to form the protrusion 42. This method of forming the protrusion 42 is preferable as it does not require any additional materials to form. However, this method leaves an aperture, in the upper face 40, where the protrusions 42 are formed. Due to these apertures, it is preferable to have the protrusions 42 be angled relative to the vertical, defined by the main face 20, as can be seen in Figure 2. More specifically, when water or other materials land on the upper face 40, they may now flow down the angled protrusion 42, or the sloped upper face 40 and enter these new apertures. For this reason, it is preferable to have the angle between the upper face 40 and the protrusion 42 be less than 90°, as depicted, as this would allow the protrusion 42 to partially cover the aperture, helping to prevent some material reaching the aperture. Though it is preferable that the angle be no less than 700 so then the protrusion 42 may still act as a deterrent, as described above, as a lower angle would flatten the protrusion 42, or at least make it easier for the intruder to flatten the protrusion, thereby neutralising the deterrent, allowing the intruder to climb the rail 10. It is also noted, as can be seen in Figure 2, the protrusion 42 is also angled relative to the main face 20, more specifically, the protrusion 42 is angled so that the slope of the inner surface of the protrusion 42 is angled away from the inner surface of the main face 20. this way any water or material that does roll off the protrusion 42, and enters the aperture at its base, is directed away from the main face 20, to reduce the risk of corrosion to the rail's inner surface and the fasteners.

Figure 3 depicts another preferred angle for the profile of the rail 10, in this case the fourth angle (0) is the angle between the plane of the rails end points 32, 52, and the vertical which is parallel to the main face 20. It is preferable for the fourth angle to be within the range of 50° -70°, or more preferably 55°-65°. This angle can be used to show how well the rear face 50 covers the inner surface of the rail 10. In particular the larger the fourth angle (8) the more of the inner surface is covered, this is why an angle larger than 50° is preferable. However, it is noted that in order to increase this angle above 70° the rear face 50 would need to be extended, to a point wherein the rear face 50 may hinder the user's ability to reach the inner surface of the of the rail 10, in order to attach the fasteners. This may result in the need to remove the lower surface 30 entirely in order to reach the fastener during construction. However, doing this would also make it easier for an intruder to reach, and remove, the fastener. Therefore, it is preferable to limit the fourth angle to be below 70°.

It is also noted that it is preferable for the surface of the rail 10 to be coated in order to provide improved protection against wear and corrosion. As previously noted, this may be achieved using paint, a powder coating, or by galvanising the rail's surface. However, by using the above-mentioned profile for the rail 10, the upper face 40, lower face 30, and rear face 50 provide some additional protection to the inner surface of the rail 10, not only protecting the inner surface from water, and other corrosive materials, but also protects the fences fasteners by making it harder for an intruder to reach them. With such features the rail may only need to apply the protective layer, of paint, powder or a galvanised layer, on the outer surface of the rail 10, which can reduce the production costs of the rail 10. Or in cases when both sides are coated, these features may help reduce the rate the protective layer wears away from the inner surface. This may be especially useful as the profile of the rail 10 makes it harder to reach the inner surface, to apply any new protective coatings.

It is also noted that the rails 10 defined above may be supplied in a kit of parts, wherein each kit provides the materials needed to construct a panel for a palisade fence, or parts for the entire fence. This kit of parts would comprise two or more of the above-mentioned rails 10, a plurality of pales which are configured to be coupled to two or more rails 10, and a plurality of fasteners to couple the pales to the rails 10. Wherein the fasteners are passed through an aperture in the surface of the pale, and a respective aperture in the main face 20 of one of the rails 10, before being fastened into place. The kit may also include a plurality of posts which are configured to be coupled to the ends of each fence panel, via apertures, or other suitable features in the ends of the length of the rails 10. It is noted that these end apertures of the rail may be coupled to the end of an adjacent rail, using a suitable fastener, to extend the length of the panels. These kits may also include a specialised tools configured to reach, and easily fasten, the fasteners through the rear face 50 and lower face 30 of the rail 10.

In the preferred embodiments the fasteners in such kits can provide additional protection features, which makes the fasteners harder to remove once the fence is constructed. In such cases the fasteners would be in the form of nuts and bolts.

Wherein these fasteners may include the aforementioned shear nut, wherein the gripping portion of the nut can be sheared off by over tightening the nut, leaving behind a thin collar, which is sufficiently strong to hold the fence together, but due to its small size and curved edges, is much harder to remove compared to a regular nut. Similarly, the bolt may comprise a sloped bolt head, which may have a conical, pyramidal, frustoconical shape, as the curved surface of the bolt head would again be harder to grip and remove with conventional tools, the points of these bolt heads may also act as a deterrent to stop intruders climbing the fence in the same manner as the protrusions 42 of the rail 10. Additionally, the bolt may comprise a shearing thread, that is to say when in use, the thread on the shank of the plurality bolts is configured to wear away under tension, to prevent the bolts re-engaging the pale, and/or rail, as this will again make it more difficult to remove the fastener from the fence.

By using the above mentioned features the present invention provides an improved rail design for a palisade fence. Wherein the rail is design with a specific profile with multiple faces, so that the faces provide protection to the inner surface of the rail 10 from water and other materials that could cause corrosion of the rail 10. The rail profile also improves security by using the position of the faces to restrict access to the inner surface of the rail 10, so that the fasteners cannot be removed from the fence by an intruder. Additionally, the rails 10 may include protrusions 42 as an additional security feature to prevent intruders from climbing the fence using the rails 10.

Claims

Claims 1. A rail for use in a palisade fence, when attached between fence posts and for the support, by means of fasteners, of pails attached to the rail; the rail (10) comprising an elongate sheet steel member having at its ends apertures for securing to posts and along its length apertures for the reception of fasteners for securing pails; the cross-section comprising; a main face (20) in which the apertures are located; a lower face (30) perpendicular to or angled away from to the main face and having a first end (32); an upper face (40) angled to the main face, and a rear face (50) angled with respect to the main (20) face and protruding away from the main face (20) and having a second end (52), wherein the upper face (40) further comprises one or more protrusions (42).2. the rail (10) of claim 2, wherein the angle between the protrusion (42) and the upper face (40) is 90° or more 3. the rail (10) of claim 2, wherein the angle between the protrusion (42) and the upper face (40) is between 60° and 70°.4. The rail (10) of any preceding claim, wherein the angle (8,10B) compared to the vertical (the main face being the relevant reference) and the first and second ends of the cross section is between 50° and 70°.5. The rail (10) of any preceding claim. wherein the lower face (30) is angled away from to the main face and is preferably between 95° and 110° (01, 10A).6. The rail (10) of any preceding claim, wherein the main face includes an inward facing protrusion, below each of the apertures in the main face (20), pointing away from the inner surface of the main face (20).7. The rail (10) of any preceding claim. wherein the rail (10) is constructed of mild steel.8. The rail (10) of any preceding claim, wherein the rail (10) is formed by cold rolling.9. The rail (10) of any of claims 8 to 9 wherein the mild steel used to construct the rail is of 1 to 3mm thickness.10. The rail (10) of any preceding claim. wherein at least the outer surface of the rail (10) is power coated.11. The rail of any preceding claim, wherein at least the outer surface of the rail (10) is galvanised.12. A palisade fence section comprising a plurality of pales fastened to two parallel rails, of the rails (10) of claims 1 to 11, wherein the pales are fastened to the rails (10) via, a plurality of bolts; wherein, when in use, the thread on the shank of the plurality bolts is configured to wear away under tension or to strip, to prevent the bolts re-engaging.13. The palisade fence section any preceding claim, wherein the pales are fastened to the rails (10) via, a plurality of bolts with conical, or frustoconical, shaped bolt heads 14. The use of a pale of any preceding claim to construct a palisade fence section comprising a plurality of pales and rails (10) of any of claims 1 to 11.15. A method of constructing a palisade fence section comprising a plurality of pales and rails (10) of any of claims 1 to 11.16. A kit of parts comprising; one or more rails (10), as per any preceding claim; a plurality of fence pale configured to be coupled to the one or more rails; and a plurality of fasteners configured to couple the pales to the one or more rails.17. The kit of parts of claim 16, further comprising a specialized tool for fastening the fasteners to the rails.18. The kit of claims 16 and 17, wherein the fasteners comprise a plurality of bolts, and a plurality of shear nuts.