Patent Publication Number: US-10329794-B2

Title: Wire retaining fence post

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to Australian Patent Application No. 2015904490, entitled WIRE RETAINING FENCE POST, filed on 2 Nov. 2015, wherein the specification and contents of which is hereby incorporated herein by reference in its entirety. 
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     Embodiments of the invention generally relate to a fence post and in particular towards fence posts that are designed to secure or grasp fencing wire without the need for manual attachment. 
     In particular, the fence posts of embodiments of the invention are designed to be driven into the ground by an automatic or semiautomatic process and the wire strung between the fence posts is inserted through the fence posts prior to time of installation into the ground. 
     Description of the Related Art 
     The installation of fence posts and fencing wire can be an arduous and time intensive task, especially when the fence to be installed spans sections of several kilometers at any one time. Such a situation is not uncommon in large farms or pastoral holdings where fence lines can extend for tens or hundreds of kilometers. 
     The manual insertion of fence posts into the ground can take a team of operators many days to complete, each post being driven into the ground separately, aligned and subsequently having the fencing wire material either attached to the fence post or inserted through an appropriate sized aperture or slot within the fence post. 
     A group of workers may go about the process of setting up a fence by first installing a series of fence posts, for example five individual fence posts, and then after the fence posts have been inserted and fixed into the ground a fencing wire, either a plain wire or barbed wire material, is then attached to the fence post by the use of nails clips or other retaining mechanisms that are known. Alternatively, the fence post may have a notch within which the fencing wire is inserted into a fencing wire retaining element is then attached to the fencing wire and clipped on to the fence. Each retaining member then has to be attached individually, one for each wire element or string attached to the fence post, which may mean anywhere from six to seven attachment points on any single fence post. 
     Such an approach takes considerable amount of time and also requires at pre-set intervals that the fencing wire be tensioned to ensure that it does not go slack over the span of the fence posts. 
     Automated or semi-automated post installation machines have now been developed that has substantially automated the driving of fence posts into the ground such that a single operator may now control a post driving machine that can take an individual post from a rack or magazine of posts and at an appropriate predetermined location drive a selected individual post into the ground using, for example, a pneumatic driving means. A single worker can therefore take a stack or magazine of fence posts and cover substantial distances in a single outing saving considerable time and effort. 
     Such post installation devices may also have pre-strung fencing wire passing through the fence post such that as the fence post is taken from the rack or magazine, fencing wire is already in place through the holes in the fence post. 
     As the post installation apparatus travels along then this fencing wire is fed out through the machine and posts hammered into place such that the operator is then constructing a complete fence system, consisting of both the fence post and the pre-strung fencing wire through the hole in the fence post, directly into the ground. In this way a completed fence can be prepared with a lot less effort. 
     For a wire in a fence the longer the span of unrestrained wire, the greater the ability of that wire to accept external loading from, for instance livestock, wildlife or flood waters. 
     Hence, a fence wire constructed free of longitudinal restraints over, say 100 meters can accept externally applied forces 10 times those that can be applied to a fence wire that has positive restraints at 10 meter centres. 
     The downside to a fence without positive restraints over hundreds of meters, is that if a wire or multiple wires are broken in one bay (between posts) by, say livestock, wildlife, or falling branches etc., then the entire section of fence will be loosened and become ineffective. 
     BRIEF SUMMARY OF THE INVENTION 
     It is an object of embodiments of the invention to overcome, or at least substantially ameliorate, the disadvantages and shortcomings of the prior art. 
     Other objects and advantages of embodiments of the invention will become apparent from the following description, taking in connection with the accompanying drawings, wherein, by way of illustration and example, embodiments of the invention are disclosed. 
     According to embodiments of the invention, although this should not be seen as limiting the invention in any way, there is provided a fence post having:
         a main body section having at least one wire receiving aperture there through for receiving a fence wire, and,   at least one wire capture structure substantially aligned with the at least one wire receiving aperture to capture the fence wire.       

     In one or more embodiments, the wire capture structure is a wire clamping member. 
     In one or more embodiments, the fence post includes an elongate channel. 
     In one or more embodiments, the fence post has a U-shaped cross section. 
     In one or more embodiments, at least one wire receiving aperture has a wire passing there through. 
     In one or more embodiments, the wire capture structure includes a locking bar. 
     In one or more embodiments, the locking bar has an open position and a closed position. 
     In one or more embodiments, the locking bar can move from the open position to the closed position. 
     In one or more embodiments, when in the closed position, the locking bar substantially restricts the movement of the wire passing through the wire receiving aperture. 
     In one or more embodiments, the locking bar urges against the wire passing through the wire receiving aperture. 
     In one or more embodiments, the locking bar urges against the wire passing through the wire receiving aperture, when in a closed position. 
     In one or more embodiments, the wire capture structure includes an inner eyelet shaped to nest within the wire receiving aperture. 
     In one or more embodiments, the inner eyelet includes at least one channel within which to receive the wire locking bar. 
     In one or more embodiments, the locking bar is substantially U-shaped. 
     In one or more embodiments, the inner eyelet is held in place within the at least one wire receiving aperture by engagement with and outer eyelet positioned on an outer surface of the fence post. 
     In one or more embodiments, the wire clamping member is spring activated. 
     In one or more embodiments, the locking bar is biased towards the closed position. 
     In one or more embodiments, the locking bar is spring biased towards the closed position so as to capitally hold the fence wire. 
     Embodiments of the invention address the above problem whilst still providing the higher loading capacity of the fence wire(s). The locking bar is designed to lift and allow wires to pass through in a controlled manner when external loads are applied to the wire(s) (such as livestock, wildlife, or floodwater flow) in a particular bay of fencing. 
     When the external loads are removed, the tensile stress in the wire(s) diminish, and the locking bar falls back to again lock the wire(s) in place. If a break of wire(s) occurs in a particular bay, the tensile force in that wire is reduced to zero adjacent to the break, and the locking bars in the adjacent posts will drop into the locked position, thus retaining all other bays of fence in a strained, workable condition. 
     Current practice for steel posts is to tie the fencing wire to each post at generally in the range of 8 meters to 12 meter centres. 
     For timber posts the thickness of the timber post and the diameter of the hole through which the wire passes combine to provide restraint to prevent wire stripping from breakage in a single bay of fence. 
     Timber posts, due to their bulk are not suited to high volume, high speed operations of the automated fencing machine. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features and advantages of the invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein: 
         FIG. 1  is a perspective view of one or more embodiments of the invention; 
         FIG. 2  is a front view of the fence post of  FIG. 1 ; 
         FIG. 3  is a side view of the fence post of one or more embodiments of the invention; 
         FIG. 4  is a rear view of the fence post of one or more embodiments of the invention; 
         FIG. 5  is a top view of the fence post of  FIG. 1 ; 
         FIG. 6  is a close-up perspective view of a rear section of the shown in  FIG. 4 ; 
         FIG. 7  is a close-up view of a front section of the fence post shown in  FIG. 1 ; 
         FIG. 8  is a perspective view of a locking bar used in one or more embodiments of the invention; 
         FIG. 9  is a perspective view of an inner eyelet of one or more embodiments of the invention; 
         FIG. 10  is a top plan view of the eyelet shown in  FIG. 9 ; 
         FIG. 11  is a cross sectional view through B-B in  FIG. 10 ; 
         FIG. 12  is a perspective view of the rear plate; 
         FIG. 13  is a cross-sectional view through C-C of  FIG. 12 ; 
         FIG. 14  is a cross sectional view through A-A of  FIG. 7 ; 
         FIG. 15  is an enlarged view of the so-called region a of  FIG. 7  showing the locking bar in a partially closed position; 
         FIG. 16  is the view of  FIG. 15  with the locking bar in an open position; 
         FIG. 17  is the view of  FIG. 15  with the outer eyelet removed and the locking bar in the closed position; 
         FIG. 18  is the view of  FIG. 16  with the outer eyelet removed, showing the locking bar in the open position; 
         FIG. 19  is a cross sectional view showing the wire capture mechanism in an open position with a wire and a wire guide in place; and 
         FIG. 20  is the view of  FIG. 19  with the wire guide removed and the wire capture mechanism in a closed position. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The fence post  10  of embodiments of the invention has a main body section  12  which is substantially U shaped having a flat section  40  with a front surface  25  and a back surface  26 , longitudinal opposing sides  16  and  18  and flanges  20  and  21 . The sides  16  and  18  for a channel  24  which defines the U shape. Other shapes of fence posts are considered to fall in the scope of embodiments of the invention, for example flat shaped fence posts. 
     The fence post  10  has a ground engaging section  30  which is driven into the ground and a wire retaining section  34  upon which there are a number of openings or apertures  38  through which wire can be strung through or received. Each opening  38  has a wire capture mechanism or structure  50 . 
     As shown in the top view of  FIG. 5 , the wire capture mechanism  50  includes the outer eyelet  42  of the flat section  14  and the rear plate  44  located on the back surface  26  and thus resides substantially in the channel  24 . 
     With reference to  FIG. 7 , a close-up perspective view of the front of the fence post  10  is shown, with the wire capture mechanism  50  shown on the front surface  25 . The wire capture mechanism  50  includes the outer eyelet  42  and the lock bar  52 . The inner eyelet  54  is partially shown in  FIG. 7 . The lock bar  52  in  FIG. 7  is shown in a closed position. 
     The lock bar  52  is substantially U shaped having straight sections  53   a  and  53   b  joined by the curved section  51 . The lock bar may be in the form of other shapes, for example a T shape in which there is only a single straight section and cross section with a flat top section or as a inverted W shape, so long as the locking bar can rest against or exert a force on a wire passing beneath it. The locking bar can be used to block a wire either within the channel  55 , as in the present example, or alternatively, if orientated correctly, against the top portion (outer edge) of the curved section  51 . 
     The lock bar  52  fits within the inner eyelet  60  which has periphery flange  62  and the inner outwardly projecting flange  64  that projects substantially perpendicular. Channels  66  are formed in the flange  64  to allow the straight sections  53   a  and  53   b  of the lock bar  52  to pass through. In another example, the inner face  54  of the straight sections  53   a  and  53   b  of the lock bar  52  may have notches thereon to provide a positive engagement with the face  68  of the channel  66  so that the lock bar  52  can only move in one direction or at least resist opening so that it can trap a wire element within. The inner eyelet  60  has the annular projection  70  which nestingly fits within the groove  80  of the rear plate  44  such that they clip together. 
     The inner plate  44  has a beveled edge  90  and flange  92 , the annular projection or rim  94  suitably shaped to fit within the appropriately sized aperture of the fence post  10 . The outer eyelet  42  over the flange  64  of the inner eyelet  60  with positive engagement of the notch  65  within an inner groove. This then holds the lock bar  52  in place whilst still allowing it to slide or travel from the open to the closed position. 
       FIG. 14  shows a cross-sectional view of the wire capture mechanism  50 , showing the engagement of the rear plate  44  with the inner eyelet  62  and the outer eyelet  42 , the lock bar  52  shown in the closed position. 
     As shown in  FIG. 15 , with the lock bar  52  in the closed position there is an opening  90  within which a wire (not shown) is trapped or restrained. The lock bar  52  may also be coupled to a biasing means (spring) so as to provide a positive holding force to that which may be in the opening  90  when in the closed position. The lock bar  52  can also function by acting to restrict the passage of a larger diameter section of wire to be held. For example, if the wire to be inserted into the opening is barbed wire then by the action of the lock bar  52  obtaining the closed position then a barb  107  will be prevented from passing through the opening. In this manner then there is no need for the lock bar  52  to have a biasing means. 
     In  FIG. 16  the bar lock  52  is in the open position which will allow wire to pass through unrestricted.  FIGS. 17 and 18  show the closed and open positions of the lock bar  52  but with the outer eyelet  42  removed for clarity. As can be seen the lock bar  52  can slidably move through the channels  66  of the inner eyelet  60 , up to the point where the edge  69  of the face  68  abuts the inner curved face of the lock bar  52 . 
       FIG. 19  shows embodiments of the invention in use in which there is a wire guide  100  passing through the wire capture mechanism  50 , the wire guide  100  being substantially tubular and hollow with a fence wire  105  with a barb  107  passing through it. The wire guide  100  prevents the lock bar  52  from engaging with the wire  105 . When the wire guide is withdrawn, the lock bar  52  falls into a closed position and prevents the barb  107  from passing through. Alternatively, the lock bar  52  may have a biasing means, such as a spring or similar, that applies a downward force onto the wire sufficient to lock it into place with a clamping effect. 
     Alternatively, the wire  105  can have two barbs positioned closely together so that when the wire guide is removed the lock bar is allowed to fall between the barbs such that if the wire were to fail or break on either side of the fence post then the wire would be prevented from pulling through the eyelet in an adjacent fence post with a locking mechanism. An adjacent fence post with a locking mechanism may not be immediately adjacent, it may be several regular fence posts away. 
     As can now be appreciated, embodiments of the invention allow for the rapid and efficient insertion of fence posts fully strung with wire passing through the eyelets of the fence posts which are able to actively hold or prevent the wire string from passing through the eyelet once the post has been taken to be inserted into the ground. Tension is applied automatically by the machine inserting the post, the wire being restrained from passing through the eyelet once the lock bar has been allowed to fall into a closed position. This then ensures that each length of wire is restrained in place under tension. Should a length of wire break during the installation process as the fence post is coming of the fence post installation machine then tension in the remaining wire string will not be lost. 
     Although at least one embodiment of the invention has been herein shown and described, it is recognized that departures can be made within the scope of the invention, which is not to be limited to the details described herein but it is to be accorded the full scope of the appended claims so as to embrace any and all equivalent devices and apparatus.