FENCECONSTRUCTION
This invention relates to improvements in fencing construction and relates particularly to an improved construction of fence post and system for erecting fence and gate posts.
Background Art Fence posts currently in use are usually made of steel or timber, although other metals are sometimes used for unsupported intermediate fence wire spacers. The erection of timber posts generally requires a post hole to be dug, either manually or with the assistance of a post hole digger, and support for the post may be enhanced by the provision of a foot or plate on the bottom end of the post or by concreting the post in the ground.
Steel posts are also generally provided with a bottom plate to support the post in the post hole, and further support is usually provided by concrete around the base of the post. Installation of such posts is generally time consuming and requires substantial amount of labour to ensure that the post is properly erected and supported. Posts used for the support of gates, and strainer posts require substantial additional work to secure gate support brackets and strainer members to the post.
It is therefor desirable to provide an improved construction of post which may be used as an unsupported intermediate fence post, a strainer post and a gate support post and which is relatively easy to erect. It is further desirable to provide an improved construction of post which does not require the use of a separate foot or the use of a concrete foundation t,o support the post.
It is also desirable to provide an improved fencing system utilizing a post which can be driven into the ground without the need to dig a post hole and which, when erected, is sufficiently strong and stable to be used for general fencing, constructions of fenced yards, can support a gate and also support strained wire fencing.
Australian Patent No. 127,755 discloses a relatively complicated construction of fence post adapted for driving into the ground and having feet which can be spread outwardly beneath the ground surface after the post is driven into the ground. The feet are contained wholly within the post while it is being driven in the ground and an inner sleeve is then forced downwardly against the upper ends of the feet within the post to drive them down and out the bottom of the post. A domed shank initially located in the bottom of the post causes the feet to splay outwardly when they are forced down by the sleeve.
This arrangement, as well as comprising a plurality of parts adapted to interreact to produce the desired result, is relatively expensive to manufacture, is time consuming to use and is ineffective in a majority of soil types.
Australian Patent No. 498,393 discloses another form of self-anchoring post comprising a plurality of angle section members united along their free edges to form a hollow member except for a portion at one end, tapering the angled section members at the one end so that upon driving the member into the ground will cause the ends to splay and lock the member in the ground. However, this construction of post is relatively expensive to manufacture due to the need to unite the plurality of angle section members, which must be of relatively heavy gauge, along their free edges, and the post so formed is relatively rigid such that minimal splaying of the tapered members occurs.
Summary of the Invention According to the present invention there is provided a fence post comprising an elongated tubular member of steel or other metal having two or more axially extending cuts or slots in the wall of the tubular member at one end thereof to provide two or more discrete end portions, the discrete end portions being shaped so as to splay outwardly when the post is driven into the ground so as to form integral outwardly splayed post supporting feet.
The invention also provides a fencing system comprising a post as described above in combination with a tubular sleeve adapted to engage with the post and be secured thereto by welding or securing means such as screws or the like, the sleeve having a socket welded thereto, the axis of the socket extending at an angle to the post axis and adapted to engage with one end of a strainer tube, and a wedge plate adapted to be driven into the ground at a location along the desired fence line and spaced from the fence post, the wedge plate having a second socket welded thereto and adapted to engage the other end of the strainer tube whereby the wedge plate strainer tube and sleeve act to support the fence post against the forces applied to the post by strained fencing wire engaged therewith.
The sleeve may be provided with two or more sockets to receive strainer tubes which extend from the post to assist in resisting stresses set up by strained fencing wire engaging the post from several different directions or to support structures such as gates or the like.
The fence system of the present invention may also include additional sleeves carrying gate support brackets, the additional sleeves being adapted to be secured to the fence post and to hingingly support a gate thereon.
In a preferred form, the tubular fence post of the invention is closed at its upper end. With such an arrangement, when the post is driven into the ground air is compressed within the post by soil entering the lower end. The air is compressed to a pressure which thereafter prevents further soil entering the space between the legs thereby assisting the legs to spread. It has been found that a post of the invention can be driven into relatively wet soil and the air pressure build-up in the post assists in causing the legs to splay in such soil. Thus, the legs of the post of the invention are caused to splay in soil conditions which otherwise would not develop sufficient splaying forces against the shaped ends of the discrete end portions .
In order that the invention is more readily understood and put into practical effect, one embodiment thereof will now be described with reference to the accompanying drawings.
Brief Description of the Drawings Figure 1 is a perspective view of a fence post formed in accordance with the present invention.
Figures 2, 3 and 4 are views of the three forms of sleeves adapted to be used with the post of Figure 1 in the fencing system of the invention.
Figure 5 is a perspective view of a wedge plate for use with the fencing system of the invention,
Figure 6 is a perspective view of a stabilizer bar and wedge.
Figure 7 is a general view of the fence post of the invention in combination with gate support brackets and strainer brackets.
Figure 8 is a view showing one method of erecting the fence post of the invention.
Figure 9 is a perspective view of the post showing one method of securing fence wire thereto.
Figure 10 shows another method of securing fence wire to the post, and Figure 11 is a perspective view of another form of post according to the invention.
Description of the Preferred Embodiments Referring to the drawings, the fence post illustrated in Figure 1 comprises a square tubular elongated post 12 formed of steel and having its upper end closed by means of a steel plate 13 which is welded around the top of the post. Adjacent the lower end of the post 12, a hole 14 is drilled in each of the four sides of the post at a position spaced from the lower end thereof. In one form of the invention, the post 12 is two metres long and the holes 14 are drilled approximately 25 centimetres froir. the lower end.
Axially extending cuts or slots 16 are made in each
(Jfl of the four sides of the lower end of the post 12, each slot 16 extending from the end of the post to the associated drilled hole 14, as illustrated. The slots 16 divide the end of the post into four discrete legs 17, the lower end portion of each leg being cut away to form points thereon. The post 12 may be used as an unsupported intermediate fence post or dropper by driving the post into the ground using, for example, a post driver as shown in Figure 8. The post driver 21 may comprise a hollow member closed at its upper end and having two or more handles 15 thereon. The post driver 21 is of a relatively heavy weight, for example, 20 kilograms, and is adapted to engage over the top of the fence post to drive the post into the ground by repeated blows on the top of the post. As the post 12 is driven into the ground, the legs
17 are caused to splay outwardly, as illustrated in Figures 7 and 8, due to the shape of the lower end of the legs 17. Additionally, soil forced into the tubular portion of the post causes an increase of air pressure within the post which also assists in splaying the legs. The splayed legs 17 act as a footing for the post 12 to firmly support the post in the ground and prevent easy removal thereof.
The fencing system of the invention utilizes the post of Figure 1 in combination with other fencing materials to provide a unique, rigid fence structure suitable for a variety of applications including sheep and cattle yards, domestic fences, paddock fencing and the like. With most fence installations, the fence post 12 is required to resist lateral forces applied thereto either by strained fencing wire or by the weight of a gate or the like secured to the post 12. For this purpose, a tubular sleeve 24, as shown in Figure 3, which has inside dimensions to enable it to slidably engage with the post 12, is adapted to be positioned along the post at an appropriate height from the ground. The sleeve 24 is secured to the post either by welding or, preferably, by use of grub screws or pointed alien head screws which engage in drilled and tapped holes 26 in the sleeve 24. The sleeve 24 is formed with a socket 27 for reception of a strainer tube 23. The socket 27 extends at an angle of approximately 25° to the horizontal.
The other end of the strainer tube 23 is supported in the ground at a distance spaced from the post 12 by a wedge plate 31 as illustrated in Figure 5. The wedge plate has a pointed lower end 32 and a lower strainer tube support socket 33 is welded to the wedge plate to extend therefrom at an angle of 25 to the horizontal when the wedge plate 31 is vertical. As shown in Figure 7, the wedge plate 31 is driven into the ground so that the top edge thereof is substantially at ground level. The wedge plate 31, strainer tube 23 and sleeve 24 support the post 12 in the upright position against the forces applied by strained fence wire 34 engaged with the post 12.
When the post 12 is used to support a gate 36, gate support sleeves 37 and 38, as illustrated in Figures 2 and 4, are mounted on the post 12 and secured thereto either by welding or, preferably, by use of grub screws or alien head screws. The upper gate sleeve 37 carries a gate support bracket 39 which is commonly used for such steel gates 36. The lower gate sleeve 38 carries a typical gudgeon pin arrangement 35 which is adapted to engage in an appropriate socket on the bottom of the gate 36. Additional support for the post 12 is provided by a sleeve 44 having outwardly extending support bars 46 which are positioned in the ground prior to driving the post 12 into the ground. The post 12 is then driven through the sleeve 44 to the desired depth. A wedge key 47 is driven between the post 12 and the sleeve 44 to secure them together. The sleeve and outwardly extending feet provide additional underground support particularly when the post is used in unstable ground. The additional sleeve and support bars 44 may be positioned at any desired depth commensurate with the length of the post.
Fencing wire 34 may be fixed to the post 12 by simply wrapping the wire around the post and twisting in the normal manner. However, to support the wire in the correct position on the post, without drilling, grooving or otherwise modifying the post, one or more resilient nylon or synthetic plastic tubes 41 are placed along the post 12, and temporarily secured thereto by plastic tape or the like, before the fencing wires 34 are engaged with the post.
The wires are then fitted around the post and the tubes 41 so that when the wires are strained they deform and compress the tubes 41 at the wire locations. The tubes are thereby held to the post and acts to maintain the desired spacing between the fencing wires as shown in Figure 9. A single tube 41 may be used, if desired, instead of the plurality of tubes shown in the drawing.
A different arrangement for securing fencing wire 34 to a post 12 is shown in Figure 10. With this arrangement, fencing wire 34 is fixed to the substantially hollow post 12 by forming the post with a slot 20 in the wall thereof, which preferably extends in the axial direction, and securing the fencing wire 34 to the post by means of a staple 30 which is an interference fit within the slot 20. A sleeve 25 of synthetic plastic material, such as nylon, may be engaged over the fencing wire 34 at that part of the wire which is to be engaged by the staple 30. The width of the slot 20 is preferably slightly less than the thickness of the staple 30 which is engaged therein to provide an adequate interference between the edges of the slot 20 and the staple 30. It has been found that such a wire securing system withstands substantial tension both in the axial direction of the post and at right angles thereto. The slot 20 may be formed in the wall of the post 12 by using an appropriate die to surround the post and a ram which is moved transversely to pierce the wall of the tubular post and thereby form a slot 20 of the desired dimensions.
In a modification of the present invention the post 12 is of a relatively short length of tubular material and the axially extending cuts or slots 16 are formed of a length which is a major part of the total length of the post 12. With this construction, the post 12 is adapted to be driven into the ground so that the top of the post is either substantially level with the surface of the ground or only a small part thereof protrudes from the ground. The post 12 thus forms a base part to receive a second post section 48 of suitable material and shape which is adapted to fit within the tubular base part in the ground. The second post section 48 may be formed of aluminium or similar ductile metal, or of timber or other material which is relatively easily sheared, and the arrangement is therefore particularly suitable for use as guide posts on the road¬ side or the like where it is undesirable for the post to be a relatively rigid barrier to a moving object. Alternatively, the second post 48 may be formed of steel or other relatively rigid material which can be used to support fencing wire or the like but wherein the second post 48 is relatively easily replaced if the post is bent or otherwise damaged. In these circumstances, the second part of the post is simply removed from the base and replaced with a further second post section. The second post 48 may be secured to the first post 12 by bolts 49 or the like, as shown in Figure 11.
With this arrangement, the base post section is able to be driven into the ground and made secure therein and the upper section thereof is relatively easily replaced in the advent of deliberate or accidental damage or destruction thereof.
It will be appreciated that other fittings may be utilized with the post 12 and system of the present invention. Thus, a post 12 erected at a corner of a fencing run or at a yard corner will be provided with one or more sleeves having strainer tube support brackets 27 extending at 90° to enable wedge plates 31 and strainer tubes 23 to be engaged with the corner post along each side of the fencing run. The post 12 may be formed of relatively thin gauge square sectioned tubular steel or other metal, or round, hexagonal, rectangular or any other suitable section. The holes and slots sufficiently weaken the otherwise
OMPI relatively rigid structure of the tubular member whereby the discrete end portions are able to splay outwardly.