DE102023105334A1 - PALISADE FENCE CROSSBAR WITH IMPROVED SHAPE - Google Patents

Abstract

Crossbar for use in a picket fence when mounted between fence posts and for support by means of fasteners from posts attached to the crossbar; the traverse comprising an elongate sheet steel member having apertures at its ends for attachment to posts and apertures along its entire length for receiving fasteners for securing posts; wherein the cross-section comprises: a major surface in which the openings are located; a bottom surface angled perpendicular to or away from the main surface and having a first end; a top surface angled toward the main surface and a rearmost surface angled relative to the main surface and projecting away from the main surface and having a second end.

Description

Picket fencing is often used for security applications where relatively strong fencing is required. The present invention relates to a picket fence beam of improved form and particularly of increased durability.

background

Picket fences are typically supplied as a kit of parts comprising posts between which posts are simply placed on top and bottom row trusses. A plurality of posts are placed vertically between the trusses to form a fence panel between the posts. Picket fences are typically set up outdoors and are usually coated and/or galvanized to reduce corrosion. The piles are typically attached to the crossheads by fasteners, usually in the form of nuts and bolts. The bolts provided may include shear nuts which capture a bolt and then notch at a given location leaving a safety collar on the bolt. These features are intended to make it difficult to loosen the fastener from the fence. Because of the snapping feature, the fasteners expose exposed metal, and the frets themselves are relatively small, so this is done on purpose so they have to grab, like a wrench. This combination of features will cause these fasteners to correlate over time, particularly in exposed areas such as coastal regions. This means that the integrity of the fence can be reduced due to this corrosion, which is usually observable on or from the very back of the fence so that it is not obvious to the casual observer.

An example of a truss to which the above features apply is in GB2372759B disclosed. This patent discloses a picket fence having a sloping surface with projections to help deter intruders, the sloping surface covering the fasteners mentioned above. A similar profile can be found in EP1366254B1 , that also as WO 02/070838 A1 is published. Relevant fasteners are also in US 5,269,208A disclosed.

There is therefore a need for a picket fence with improved durability without increasing costs that effectively improves an engineering structure. In the case of the present invention, the design is improved by making adjustments to the profile of the crosshead, as detailed below. In this way the design can be improved without the need for additional materials and therefore little or no additional cost should result. From the above there is also a need for this improved design to provide improved protection for the fasteners as well as for the surface of the crosshead to help prevent wear and corrosion.

abstract

The present invention is as defined in the claims.

The present invention provides: a crossbar for use in a picket fence. The trusses are coupled to a plurality of fence panels to form a fence panel, then the ends of the trusses are configured to be attached with suitable fasteners between the fence posts to support the fence panel. The plurality of posts are also attached to the crosshead by fasteners. The truss itself comprises an elongate sheet steel member having apertures or other suitable features at its ends for attachment to the posts, and apertures along its length for receiving fasteners for attaching the posts to the truss; the traverse has a cross-section perpendicular to the longitudinal axis, the cross-section having a major surface in which openings are a lower surface perpendicular to or angled away from the major surface and having an upper surface angled toward the major surface extending from from the opposite end of the main surface to the bottom surface. This top surface may optionally include protrusions to act as a deterrent. And a rearmost surface, which is angled with respect to the main surface, protrudes from the end of the upper or lower surface remote from the main surface in a direction away from the main surface.

Compared to the closest prior art, GB2372759B , the present invention differs in that the rearmost surface is angled with respect to the main surface and the addition projects away from the main surface. This effectively protects the rearmost part of the main face, the face of the truss where the snap-off fasteners are usually attached. In comparison, the prior art discloses that the rearmost surface is parallel to the main surface. Designs of this type as shown in the mentioned prior art have not undergone any changes in the past 20 years even in the face of the known problem.

Preferably, in the present invention, the angle between the vertical (the major surface being the relevant reference) and the first or second end of the traverse defined by the end of the rearmost surface of the cross-section is between 50° and 70°. By using angled end sections compared to the parallel ends of the prior art, the claimed trusses provide better shielding to protect the inner surface of the truss. That is, the more flared end portions can deflect rain and other potential erosion factors, such as windblown sand, away from the traverse over a wider range of angles, thereby providing improved protection. This preferred range of angles also serves to reduce access to the fasteners coupled to the main face of the crossbar, making it more difficult for intruders attempting to tamper with the fence by attempting to loosen the fasteners below the flared end portions, these ends also making it difficult for the intruder to turn tools, such as wrenches, once the fastener is reached because the tool must be positioned at an angle relative to the crosshead running surface. It should be noted that the other end of the crosshead, defined by the top or bottom surface, whichever is not connected to the rearmost surface, may be at a similar angle with respect to the vertical, again for environmental protection to provide and restrict access to the fasteners.

It should be noted that the front face of the fasteners, usually in the form of a screw, are conventionally protected by the crosshead, i.e. the shank or pin of the fastener is usually covered by the profile of the crosshead, thereby protecting it from intruders and the environment is protected. In the case of the claimed invention, this protection is provided by the upper surface at the end portions of the crosshead, which helps to provide protection from weather and other environmental corrosion factors by using the protected surfaces of the crosshead to attach the bolts and nuts or the mounting collar , which is attached to the screws. It is also noted that the heads of the screws are usually exposed and are therefore coated or zinc plated to protect them from corrosion, it is also noted that the shear surface of the screw heads is wider than the aperture that accepts the fastener, the may provide some protection for the internal surface by preventing environmental corrosion factors from reaching the openings within the crosshead, however, in some cases the profile of the crosshead may be shaped or angled to protect the bolt heads, again by protecting the bolt head from environmental factors shielded, although this effect can also be achieved by coupling the piles to the truss with the bolt head recessed into either the pile or truss surface. It is noted that the claimed post profile, while protecting the fasteners, still allows adequate access for the construction of a picket fence. In particular, while the picket fence is being built, the trusses and posts can be placed along the ground or other flat surface to allow the user to access the fasteners from the direction facing the bottom end portion of the truss to complete the building then, once erected, the direction used to access the fasteners is facing down towards the ground and is not covered by the lower surfaces of the truss, with the other directions being at least partially covered by the upper surface and the flared end portions of the traverse, making access to the fasteners difficult once the fence is erected.

It is also noted that a preferred range for the angle between the vertical major surface and the end portions is 55° to 65°. It is ideally envisioned that angles are large to provide better coverage of the truss interior surface, thereby providing more protection. However, angles above the disclosed range would provide improved protection, but would also impede access to the interior surface to an extent that the user would be unable to adequately access the fasteners to build the fence panels. The preferred range therefore provides a compromise in which improved protection is provided compared to the prior art, while also allowing sufficient access to the inner surfaces of the crossbar to construct the fence with relative ease. However, as mentioned, it is also desirable to prevent some access to the fasteners as this helps deter intruders attempting to remove the fasteners from the fence being constructed.

For reference, in this technical field, small changes in shape can be significant, affecting requirements for providing sufficient security and for the volume of the product produced can. An example of this can be found by comparing the pile profile with that shown in W09533113A1 and GB2573388B is shown. In particular, the 6 , 8th , 10 and 11 from W09533113A1 Provides information on how the angle and thickness of the profile of a fence post made from sheet metal affects the force that can be withstood before the post deforms. The same information can be applied to the sheet metal used to form the truss. The user desires deflection/absorption of great force to provide improved security for the site where the fence is placed, in and around. However, as noted in that specification, the benefits of increasing the thickness of the sheet material or the angles of the profile decrease with increase, noting particularly with regard to angles that the benefits decrease rapidly as the angle approaches 90°, hence a range of 50° - 70° was probably preferred. It is also noted that increasing the thickness of the sheet material used to form the truss can also increase production costs since the fence requires more material and greater force to form, reducing the production rate for the truss.

In some embodiments, the bottom panel or end portion may be folded over such that the inner surface of the bottom panel is parallel to or even touching the inner surface of the main panel. This is done to provide protection to the inner surfaces, however the space between the inner surfaces can pose additional problems as water likely to reach the inner surface through the openings in the main panel can become trapped within the fold between the main panel and the lower surface, thereby more corrosion is caused on these surfaces. In the presented truss, the lower surface can be angled away from the main surface, this stops water collecting under the openings near the fasteners and therefore reduces corrosion. The angle is preferably between 95° and 110° (01, 10A) as it retains considerable rigidity to withstand forces against the fence, provides some shielding for the truss interior surface while also stopping puddles of water by allowing water to flow off the slant drain the lower surface.

It is also noted that the present invention may include one or more protrusions in the top surface of the crosshead. In particular, the top surface may include pointed protrusions that are vertical with respect to the plane of the top surface. Such projections would be positioned between the apertures used to receive the pilings and/or posts so that when erected the projections would be positioned on the portions of the truss between the attached posts/piles. The pointed projection, like the spikes on top of the picket fence posts, can act as a deterrent to an intruder attempting to grasp or step on the traverse. It is noted, however, that it may be preferred for such projections to be angled with respect to the top surface of the crosshead rather than perpendicular. Particularly if the projection has an angle below 90°, such as an angle in the range 60° - 70°, as this way less of the inner surface of the projection is exposed to the environment which can help reduce the risk of corrosion to the projection itself to reduce while still being sufficiently sharp/angled to serve as a deterrent. Alternatively, the protrusion may have an angle greater than 90° to help prevent corrosion on the inner surface of the crosshead, specifically the inner surface of the major face. As this larger angle may mean that water draining over the boss into the gap/opening formed when the boss is made with the sheet metal of the crosshead will be deflected away from the inside surface of the crosshead. However, it is also noted that larger angles expose the inner surface of the boss, thereby increasing the risk of corrosion on the boss itself.

It is also noted that a similar projection can be formed when making the apertures to receive the fasteners. In particular, these protrusions may face inwards and have a large angle, in excess of 90°, with respect to the main face of the cross-member so that the protrusion can be flattened by the fastener once secured in place. The purpose of these inwardly facing protrusions is also to protect the inner surface of the crosshead as such protrusions would help deflect water entering the opening away from the crosshead inner surface and when flattened the protrusion still has some part of the interior surface, again protecting it from water and other environmental corrosive factors.

With regard to the manufacture of the above-mentioned trusses, it should be noted that such trusses are generally preferably made of a strong material to provide strength and withstand impact. However, it should be mentioned that the traverse may also be made of one material The need for elastic deformation, in addition to providing strength, allows such deformation to be used to better absorb the force of an impact and when building the fence to better align the trusses and posts, particularly under adverse conditions Environmental conditions that make it difficult to set up the fence rails parallel to each other and the posts perpendicular to the rails, such as an uneven surface. To this end it is preferred that the claimed cross members are made of a material such as mild steel. Mild steel is made from steel that is both strong and generally weather resistant, but has the added benefit of being pliable enough to deform elastically when the fastener is tightened to help hold the stake during construction of the picket fence.
Finally, there is a need to consider the thickness of the material used to form the truss. As for the present invention, the thickness must be thin enough to allow material to flex when the post is formed and allow the post to elastically deform easily when the fence is built while also being sufficient strength is provided.

It is noted that if the material is too thick, it would not be able to provide the necessary flexibility for elastic deformation and might also be more difficult to shape since more force would be required to bend the material. Based on British standards set out in BS1722-12:2006 Table 6 in relation to the thickness of different pile concepts it should be noted that for safety the standard for the deformable D section is 3mm whilst for the W -cross section is 2 mm. A thickness between 1 mm and 3 mm would therefore be preferable for the present invention. Since the truss needs to have properties similar to those of the pile, it may be reasonable to assume that similar materials can be used. This thickness of 2-4mm is perhaps best as this is the easiest to form and provides the most flexibility whilst still giving the truss sufficient strength to withstand impact. The reason for this is that this range provides a truss with the optimum thickness that is malleable, easy to attach while still being relatively strong. For example, if the fence is made thinner than this, it would not have enough surface area to grip the fastener, in addition, if the fastener is overtightened, there is a risk that the fastener will damage the truss because the thin surface will bend or under the additional tension breaks. It is also noted that the thinner trusses would also be more easily damaged, within impacts on the surface of the truss causing the fence panel to flex and possibly fracture. In addition, it is preferred that the truss be thicker than the stakes attached to it, since each truss must support multiple stakes. Alternatively, if the pile is made too thick, it may be more difficult to deform due to the extra force needed to deform the extra material. Additionally, the user may need larger fasteners to secure the stake in place, which may be more difficult to tighten by hand due to the increased grip on the thicker crosshead. This means that a thin stake would be too weak to provide security, while a thick stake would be more difficult to shape when forming the truss. As mentioned, it is therefore preferred to have a crossbar with a thickness of between 1 and 4 mm, since this thickness provides sufficient grip and strength while still being elastically deformable.

In addition, the use of mild steel may allow the trusses to be manufactured using a cold rolling process. It should be noted that it is generally preferable that picket fence rails be manufactured by a cold rolling process rather than a hot rolling process and therefore must be made of a suitable material that can be formed by the cold rolling process. The reason for this preference is that forming the truss using a hot rolling process creates internal stresses within the material while the heated material/alloy is undergoing the hot rolling process because the heated metal/alloy can be more ductile than the same material , when it is cold, leading to the creation of weaknesses in the areas affected by these internal stresses. However, using a cold rolling process does not create these internal stresses and therefore piles made using the cold rolling process should not have the same weak points and therefore should generally be stronger. As a result, the cold rolling process provides a better truss standard.

It is also noted that the truss can be powder coated prior to assembling the fence to help protect the surfaces of the truss from the environment. It is also noted that a powder coating would provide better protection compared to a painted pole.

An alternative to powder coating is to galvanize the surface of the truss. Additionally, the galvanized finish may be preferred over a paint finish or powder coating as the galvanized finish is pliable and therefore less likely to crack or break while the truss finish is loaded when attached to a multitude of poles . This provides improved protection as such cracks in the powder coating would leave portions of the crosshead surface exposed to the environment.

It should be understood that the trusses of the present invention may be presented as part of a kit of parts. The kit provides all the features needed to build one or more fence panels as described above. Such a kit may include at least one truss as described in the present invention, preferably two per span for better support, a plurality of posts to be attached to the trusses, and a plurality of fasteners used to secure the posts on the trusses by inserting the fastener through an aperture in the post and a corresponding aperture in the truss.

It is noted that in the preferred embodiment the fastener would take the form of nuts and bolts since they are relatively easy to use and manufacture and provide sufficient strength for security purposes. The threaded shank of the screw is passed through an opening in one of the piles and through a corresponding opening in the main face of the truss. Once in place, the nut can be attached to the shank of the bolt and tightened to grip the crosshead and post between the nut and bolt head. It is noted that nuts and bolts may include additional security features to make it more difficult for an intruder to remove the fastener. Such features include the shear nut mentioned above, wherein the gripping portion of the nut can be sheared off by over-tightening the nut, leaving a thin collar that is sufficiently strong to hold the fence together but is much more difficult to remove due to its small size and curved edges is than a conventional mother. Similarly, the screw may include a beveled screw head, which may have a conical, pyramidal, frusto-conical shape, since the curved surface of the screw head would again be more difficult to grip and remove with conventional tools. Additionally, the bolt may include a shear thread, that is, the threads, in use, on the shank of the plurality of bolts are configured to wear under tension to prevent the bolts from re-engaging the pile and/or truss. as this would again make it difficult to remove the fastener from the fence.

drawings

• The present invention is illustrated by one of the following diagrams, in which 1 Figure 12 shows a cross-section of the crosshead (10) having a cross-section perpendicular to the longitudinal axis having a main surface (20), top surface (40) and end portions (32, 52) having a bottom surface (30) and a rearmost surface (50) and includes the optional boss (42).
• 2 shows the same cross section as 1 , where the preferred angles between the different faces of the traverse and for the boss are given.
• 3 shows the same cross section as 1 , where the preferred angle between the end portions of the traverse is indicated with respect to the vertical.
• 4 shows a section of the outer surface of the traverse.

Specific Description

1 Figure 12 shows a cross section of the preferred embodiment of the present invention. In particular, the illustrated crosshead 10 includes a cross-section perpendicular to the longitudinal axis of the crosshead 10 including a major surface 20, an upper surface (40), end portions 32, 52, and a rearmost surface 50, it also being noted that the illustrated crosshead includes the additional includes optional features of bottom surface 30 and includes optional protrusion 42 . The major surface 20 defines the vertical axis of the crosshead and includes a plurality of apertures spaced along the crosshead. The openings are configured to receive a fastener used to attach a plurality of fence posts to the disclosed crosshead 10 . The ends 32, 52 of the rails may also include additional openings or features to secure each end of the rails to a respective post, thereby securing the panels of the picket fence between the posts. It should be noted that the openings or features at the end of the truss 10 may in some cases be coupled together with a suitable fastener to form longer trusses, if desired This may be the case where an adverse environment means that one or more posts could not be placed around the perimeter of the area to be protected.

The crosshead 10 then includes an upper surface 40 which is angled with respect to the main surface 20 . The top surface 40 provides some additional protection for the crosshead 10 . In particular, the sloping surface provided by the top surface 40 may be more difficult for an intruder to grasp and/or climb when attempting to climb over the fence. Further, the top surface 40 is preferably angled such that it extends rearwardly, from the perspective outside of the fence, thereby providing coverage for the interior surface of both the top surface 40 and the main surface 20, which may help reduce the risk of corrosion on the crosshead 10 and the fasteners attached to the crosshead 10. In addition, the beveled surface helps water, particularly rain or other corrosive materials, to drain off the surface of the crosshead 10, and the beveled surface also directs the flow of water away from the interior surface, thereby helping to further reduce the risk of corrosion to reduce. As also in 1 As shown, the top surface 40 may include a plurality of protrusions 42 along its length. These protrusions 42 would be placed along the surface of the top panel 40 such that when the fence is built, the protrusions 42 are positioned between the posts of the fence. These projections can act as a deterrent to intruders attempting to climb over the fence, much like the spikes at the top of picket fence posts, as the projection can prevent the intruder from grasping or stepping on the traverses.

The crosshead 10 also includes a rearmost surface 50 extending from the end of the top surface 40 remote from the main surface 20 . The rearmost surface 50 extends downwardly with respect to the vertical defined by the plane of the major surface 20 . It is noted that the rearmost surface 50 is angled relative to the main surface 20 such that the main surface 20 and the rearmost surface 50 are not parallel. The purpose of the rearmost surface 50 is to provide protection for the inner surface of the crosshead by shielding the inner surface of the crosshead from weather and other factors that may cause the crosshead 10 to corrode. It should be noted that the rearmost surface 50 is preferably angled away from the main surface 20 , thus the outwardly swept rearmost surface 50 provides a sloping surface that directs water and other material on the crosshead 10 away from the crosshead 10 can, specifically away from the inner surface. In addition, the angled rearmost surface 50 can provide improved protection compared to a surface that is parallel to the main surface 20 because the slanted surface can shield a wider range of incidence angles, i.e. the angled wall is able to block water, particularly rain and other precipitation, from a wider range of gradients/angles. The angled rearmost surface 50 may also help discourage an intruder's attempts to vandalize the picket fence by making it more difficult to reach the interior surface to loosen the fasteners supporting the fence's posts as the intruder around the angled slope of the rearmost wall 50 should be enough.

Crosshead 10 may also include a bottom surface 30 coupled to the end of main surface 20 remote from top surface 40 . The bottom surface 30 extends inwardly from the main surface 20 . The purpose of this surface, similar to the rearmost surface 50, is to protect the inner surface of the crosshead by acting as a shield that can deflect water and other materials away from the crosshead 10 that may cause corrosion. It is preferred that this lower surface is angled with respect to the main surface 20, in particular the lower surface should form an angle of 90° or more with respect to the inner surface of the main surface. If the bottom surface 30 has a smaller angle, there is a risk of water or other material being trapped within the space between the main surface 20 and the bottom surface 30 , particularly when water passes through the opening of the main surface 20 . This trapped material increases the possibility that the crosshead 10 will rust. It is therefore preferred that the bottom surface 30 is angled, at least perpendicularly with respect to the main surface 20, in this way water entering the space between the inner surfaces of the main surface and the bottom surface 30 will drain off the bottom surface 30 can. In addition, as with the rearmost surface 50 and the top surface 40, the bottom surface 30 can help impede an intruder's access to the fasteners that secure the fence since the bottom surface 50 acts as a physical barrier preventing the Access to fasteners blocked, making it difficult for an intruder to vandalize the fence or remove a fence post.

It should be noted that the illustrated crosshead 10 is preferably made from a strong sheet material, such as mild steel, which can be formed into the desired profile using a rolling process, particularly a cold rolling process. It should be noted that sheet material is preferred as it can be used to produce a large volume of trusses in a relatively short amount of time. Mild steel or similar metal/alloy materials are preferred as they provide strength even when the material is thin and is typically malleable, allowing them to be readily shaped. It is noted that steel is more preferred since steel tends to resist corrosion, particularly due to water. It is noted that the rolling process is preferred as it again produces a large volume of product in a short time. It should be noted that a cold rolling process is preferred to a hot rolling process because the heated portions of the sheet material can create weak points after they cool due to the difference in tensile strength between the cold and heated metal.

2 depicts examples of the preferred angles for the truss profile. In the example shown, the first angle (θ1i) between the main surface 20 and the lower surface 30 is 90°. It is noted that the angle for the first angle (θ1-i) should not be less than 90°, because if the angle is smaller, water and other material can be trapped between the bottom surface 30 and the main surface 20 because the bottom surface 30 would be angled toward the main surface 20, that is, the terminus 32 of the bottom surface 30 would be brought closer to the inner surface of the main surface. Angles greater than 90°, on the other hand, slope the bottom surface 30 away from the main surface 20 , creating a slope where water and other materials can run off the bottom surface 30 and be deflected away from the main surface 20 . However, the use of these large angles would reduce the amount of shielding that the bottom surface 30 provides because the inner surface of the major surface would be more exposed to the environment. The 90° angle is therefore the best as it provides the greatest amount of shielding for the inner surface of the crosshead and does not trap any material between the bottom surface 30 and the main surface 20. It should be noted that this shielding also protects the fasteners that support the fence by making it difficult for an intruder to reach the inside surface of the truss.

The second angle (θ2) depicts the angle between the main surface 20 and the top surface 40 . It is preferred that the top surface 40 be angled relative to the main surface 20 rather than perpendicular because the sloping top surface 40 allows water and other materials to drain off the top surface 40 . Namely, if the top surface 40 is perpendicular to the materials of the major surface, water could collect or puddle on the surface of the top surface, increasing the risk of crosshead 10 corrosion. It is also noted that the second angle (θ2) is preferably greater than 90° because if the angle is 90° or less, an intruder may be able to use the crosshead 10 as a step to get over the to climb the fence. With a larger angle, however, the slope of the top surface would be angled towards the front of the fence, outside the protected area, and therefore it would be more difficult to climb from outside the fence. It is also noted that the top surface 40 also provides protection for the inner surface of the crosshead. Like the bottom surface 30, as the second angle (θ2) increases, moving the top surface 40 to be more parallel to the main surface 20 decreases the amount of protection provided by the top surface. An angle of 120° is therefore preferred as it slopes the top surface 40 towards the main surface 20, allowing material to drain and making it difficult for an intruder to climb over the crosshead 10 while also allowing the top surface 40 to provide a sufficient amount of shielding for the inner surface of the crosshead to help prevent corrosion of the crosshead 10 at the fasteners coupled to the crosshead 10 .

The third angle (θ3) shows the angle between the top surface 40 and the rearmost surface 50. In the example shown, the third angle (θ3) is 90°, but it should be noted that for the rearmost surface 50 the important factor therein is that the rearmost surface 50 slopes away from the main surface 20. In this way, water and other materials can run off the sloping surface of the rearmost surface 50 and be directed away from the inner surface of the crosshead. In addition, by not paralleling the rearmost surface 50 with the main surface 20, the rearmost surface 50 can better shield the interior surface since the slanted rearmost surface 50 blocks precipitation, such as rain, from a wider range of angles relative to the main surface 20. Furthermore, the sloping rearmost surface 50 makes it difficult for an intruder outside the fence to reach the inner surface of the crossbar to loosen the fence fasteners because of the angled rearmost surface 50 increases the distance between the traverse end point 52 and the main surface 20 over which the intruder could not reach to access the fasteners. It is also noted that if the second angle (Θ2) is changed, the third angle (θ3) will require a corresponding change in order for the rearmost surface 50 to remain at the same angle with respect to the main surface 20 since the selected angle is the provides the best compromise between shielding the inner surface while increasing the gap between the main surface 20 and the terminus 52 of the rearmost surface 50.

Finally forms 2 also a preferred angle for the protrusion 42 on the top surface 40. It should be noted that the protrusion 42 is designed to face out of the top surface 40 to create a point to help prevent an intruder from grasping or stepping on the crosshead 10 while attempting to to climb over the fence. An example of the preferred embodiment of the projection 42 is shown in FIG 4 1, wherein the protrusion 42 is formed by cutting into the surface of the top surface 40, then folding a portion of the cut portion of the top surface 40 upwardly away from the inner surface of the crosshead to form the protrusion 42. This method of forming protrusion 42 is preferred because it requires no additional materials to form. However, this method leaves an opening in the top surface 40 where the protrusions 42 will be formed. Because of these openings, it is preferred that the protrusions 42 be aligned with respect to the vertical defined by the major surface 20 as shown in FIG 2 visible, are angled. More specifically, when water or other materials land on top surface 40, they may not flow down angled projection 42 or slanted top surface 40 and enter these new openings. For this reason, it is preferred that the angle between the top surface 40 and the protrusion 42 be less than 90° as shown, as this allows the protrusion 42 to partially cover the opening, which helps prevent some material reached the opening. Although it is preferred that the angle be no less than 70°, the protrusion 42 can still serve as a deterrent as described above since the lesser angle would flatten the protrusion 42 or at least make it easier for an intruder to flatten the protrusion , thereby neutralizing the deterrent and allowing the intruder to climb over the traverse 10. It is also noted that, as in 2 visible, the protrusion 42 is also angled with respect to the main surface 20, more specifically the protrusion 42 is angled such that the slope of the inner surface of the protrusion 42 is angled away from the inner surface of the main surface 20. In this way, water or material that does not roll off the boss 42 and enter the opening at its base can be directed away from the main surface 20 to reduce the risk of corrosion of the inner surface of the crosshead and fasteners.

3 Figure 12 depicts another preferred angle for the crosshead 10 profile, in which case the fourth angle (θ) is between the plane of the crosshead endpoints 32, 52 and the vertical parallel to the major surface 20. It is preferred that the fourth angle is within the range of 50° - 70°, or more preferably 55° - 65°. This angle can be used to show how well the rearmost surface 50 covers the inner surface of the crosshead 10 . In particular, the greater the fourth angle (θ) is, the more of the inner surface is covered, therefore an angle greater than 50° is preferred. However, it should be understood that to increase this angle beyond 70°, the rearmost surface 50 would need to be expanded to an extent where the rearmost surface 50 could interfere with the user's ability to reach the inner surface of the crosshead 10 for attaching the fasteners . This may result in the bottom surface 30 having to be removed entirely to access the fastener during construction. However, this would also make it easier for an intruder to reach and remove the fastener. It is therefore preferred that the fourth angle is limited to below 70°.

It is also noted that it is preferred for the surface of the crosshead 10 to be coated to provide improved protection from wear and corrosion. As mentioned above, this can be achieved using paint, a powder coating or by galvanizing the surface of the truss. However, by employing the profile mentioned above for the crosshead 10, the top surface 40, the bottom surface 30 and the rearmost surface 50 provide some additional protection for the inner surface of the crosshead 10 by not only protecting the inner surface from water and other corrosive materials, but also protect the fasteners of the fences by making them more difficult for an intruder to reach. With such features, the truss may only require the application of the protective coating of paint, powder or a galvanized layer to the outer surface of the truss 10, which can reduce the production cost of the truss 10. In cases where both sides are coated, these features can help reduce the rate at which the protective coating wears away from the inner surface to reduce. This can be particularly useful as the profile of the crosshead 10 makes it difficult to reach the interior surface to apply new protective coatings.

It is also noted that the trusses 10 defined above may be supplied in a kit of parts, each kit providing the materials needed to construct a bay for a picket fence, or parts for the entire fence. These kits of parts would include two or more of the above-mentioned crossheads 10, a plurality of poles configured to be coupled to two or more crossheads 10, and a plurality of fasteners for coupling the poles to the crossheads 10. The fasteners are passed through an opening in the surface of the pile and a corresponding opening in the main face 20 of one of the cross members 10 before being fastened in place. The kit may also include a plurality of posts configured to be coupled at the ends of each fence panel via openings or other suitable features in the ends of the length of the crossbars 10 . It should be noted that these crosshead end openings may be coupled to the end of an adjacent crosshead using a suitable fastener to extend the length of the panels. These kits may also include specialized tooling configured to reach and readily fasten the fasteners through the rearmost surface 50 and bottom surface 30 of the crosshead 10 .

In the preferred embodiments, the fasteners in such kits can provide additional protective elements that make it difficult to remove the fasteners once the fence is built. In such cases, the fasteners would be in the form of nuts and bolts. These fasteners may include the shear nut mentioned above, where the gripping portion of the nut can be sheared off by over-tightening the nut, leaving a thin collar that is strong enough to hold the fence together but much more difficult to do due to its small size and curved edges remove is than a conventional nut. Similarly, the screw may include a beveled screw head, which may have a conical, pyramidal, frusto-conical shape, since the curved surface of the screw head would again be more difficult to grip and remove with conventional tools, the tips of these screw heads also acting as a deterrent to deter of intruders climbing over the fence, act in the same way as the projections 42 of the crossbar 10. Additionally, the bolt may include a shear thread, that is, the threads, in use, on the shank of the plurality of bolts are configured to wear under tension to prevent the bolts from re-engaging the pile and/or truss. as this would again make it more difficult to remove the fasteners from the fence.

Utilizing the above features, the present invention provides an improved rail design for a picket fence. The crosshead is designed with a specific profile with multiple faces such that the faces provide protection for the inner surface of the crosshead 10 from water and other materials that could cause corrosion of the crosshead 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 such that fasteners cannot be removed from the fence by an intruder. Additionally, the rails 10 may include protrusions 42 as an added security feature to prevent intruders from climbing over the fence using the rails 10 .

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• GB 2372759B [0003, 0007]
• EP 1366254 B1 [0003]
• WO 02/070838 A1 [0003]
• US5269208A [0003]
• WO 9533113 A1 [0011]
• GB 2573388B [0011]

Claims (14)

Crossbar for use in a picket fence when mounted between fence posts and for support by means of fasteners from posts attached to the crossbar; the traverse (10) comprising an elongate sheet steel member having apertures at its ends for attachment to posts and apertures along its entire length for receiving fasteners for securing posts; where the cross-section includes: a major surface (20) in which the openings are located; a bottom surface (30) angled perpendicular to or away from the main surface and having a first end (32); a top surface (40) angled to the main surface, and a rearmost surface (50) angled relative to the main surface (20) and projecting away from the main surface (20) and having a second end (52). Traverse (10) to claim 1 wherein the top surface (40) further comprises one or more projections (42). A truss (10) as claimed in any preceding claim, wherein the angle (e, 10B) compared to the vertical (the major plane being the relevant reference) and the first and second ends of the cross-section is between 50° and 70°. A crosshead (10) as claimed in any preceding claim, wherein the major surface includes an inwardly facing protrusion under each of the openings in the major surface (20) which faces away from the inner surface of the major surface (20). A crosshead (10) as claimed in any preceding claim, wherein the crosshead (10) is constructed of mild steel. A crosshead (10) according to any preceding claim, wherein the crosshead (10) is formed by cold rolling. Traverse (10) after one of Claims 8 until 9 , where the mild steel used to build the truss is 1 to 3mm thick. A truss according to any preceding claim, wherein at least the outer surface of the truss (10) is galvanized. Picket fence section comprising a plurality of posts attached to two parallel trusses of the trusses (10) of Claims 1 until 12 are attached. Palisade fence section after Claim 13 , wherein the piles are attached to the trusses (10) by a plurality of screws; wherein, in use, the threads on the shank of the plurality of screws are configured to wear under tension to prevent the screws from re-engaging the pole and/or truss (10). Palisade fence section after Claim 13 or 14 , wherein the piles are attached to the trusses (10) via a plurality of screws with conical or truncated screw heads. Use of a post according to any preceding claim for constructing a section of picket fence comprising a plurality of posts and trusses (10) according to any one of Claims 1 until 12 includes. A method of constructing a section of picket fence comprising a plurality of posts and trusses (10) according to any one of Claims 1 until 12 includes. Parts kit that includes: one or more trusses (10) according to any preceding claim; a plurality of fence posts configured to be coupled to the one or more trusses; and a variety of fasteners, configured to couple the piles to the one or more trusses.

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