Abstract:
An articulating fence post and gating system, which resiliently articulates from an upright position, perpendicular to the ground, to a flattened position, parallel with the ground, is described. The gating system comprises at least one resiliently articulating fence post, where the posts are connected by strands of fencing material. The gating system may be disposed with a standard stationary fence or an articulating fencing system. The gating system of the present invention avoids damage from a collision between farm equipment, such as a mobile irrigation system, and the fence by having the gating portion resiliently articulate, from an upright position to the ground, in order to allow the mobile equipment to run over the gate portion without breaking fence posts or snapping strands of fencing material. Once the equipment completely rolls over the gated portion of the fence, the gated portion automatically returns to its upright position.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation-in-part of application(s) application Ser. No. 09/399,126 filed on Sep. 20, 1999, now U.S. Pat. No. 6,343,778. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an articulating fence post for a fencing or gating system and, more particularly, to a radially articulating fence post and gating system. 
     2. Description of the Related Art 
     Farmers and ranchers use fences, walls, hedgerows and other boundary markers to demarcate territory, and to control ingress and egress of persons and animals from and to the territory boundaries. With the advent of large cattle and sheep ranches, particularly in the Western United States, fences are used primarily to restrain domestic livestock from leaving a fenced-in or enclosed area. These fences are typically built from four or five horizontally spaced strands of barbed wire, or smooth wire mounted on wooden fence posts that are driven into the ground. A single fence, often stretching for miles, is used to delineate a “range” or “pasture” where herds of cattle, or other grazing animals, are confined. 
     In recent years, the use of fencing to delineate multi-purpose land utilization has become more prevalent in all regions of the country making ingress and egress from these restricted areas more of a concern. In all areas of the country, multi-purpose land use methods have brought crop cultivation and the raising of livestock together on the same land. These multi-use methods involve dividing a tract of land into several parcels and rotating the function of the parcels between crop cultivation and livestock feeding. These methods typically involve concentrating dense populations of livestock, such as feeder cattle and dairy cattle, on one parcel while crops, such as grains and seeds, are being cultivated on the others. Since cattle fed in this manner are in high density, barbed wire fences, and fences that have electrified strands of wire, are needed to confine the cattle in the parcel. Multi-purpose land use methods have gained widespread acceptance in the agriculture business because they generate increased yields of table meat from cattle by providing abundant food supplies for fattening cattle prior to slaughter. 
     With the requirement for increased agriculture production, especially in arid climates, sophisticated irrigation systems and methods have become a necessity to increase acreage yields. Today, these systems are usually automated, using computers, and can cover extended acreage without being manned. Water pressure and electricity are commonly used to provide the energy to move these systems. The irrigation systems have mechanized means of movement such as drive wheels mounted under spray irrigation carriages. A pivotal irrigation system, for example, is anchored at a center point and rotates about that point on large cleated wheels, mounted under a spray irrigation carriage, to sweep out an irrigation circle, which can be a mile or more in diameter. 
     The close proximity of cattle pastures and domestic crops created by modern, multi-purpose land use methods have put an unforeseen burden on irrigation systems. Typical stationary fence posts, necessary for separating cattle pastures from growing crops, greatly hinder the mobility of irrigation systems over a tract of multi purpose farmland. Large irrigation systems designed to efficiently irrigate large tracts of land, such as pivotal irrigation systems, become impractical if stationary fence posts obstruct them. 
     One approach, which allows a fenced area to be irrigated, has been to place gaps in the fence, which are wide enough for the cleated wheels of the irrigation system to pass. Unfortunately, the cleated wheels are so wide that the gaps in the fence are large enough to let livestock, including cattle, pass as well. 
     Another approach is to have crews move the fence in the path of the irrigation system and then replace it. This is labor intensive and expensive. It would therefore be advantageous to have fence posts that could articulate under the force of the moving irrigation system wheels, yet be resilient enough to retain livestock. Unfortunately, there are a number of problems associated with such a system. First, the fence posts must be able to yield to the force of the cleated wheels and articulate from its upright position, perpendicular to the ground, to a substantially flattened position that is parallel with the ground. Second, the fence system must maintain the strand integrity to keep from snapping wire strands as the fence articulates. 
     There are additional problems with prior art fence post systems. Those that have some kind of resilient means, such as a spring mechanism, which allow the fence posts to spring back to an upright position after being knocked down by the irrigation system, are hinged at their base so as only to pivot in a single plane. If an irrigation system does not approach the fence post from a direction that is perfectly aligned with the articulation direction of the fence post system, then the irrigation system imparts side loads on the fence posts and can cause permanent damage to both the fence post and irrigation systems. This problem is particularly acute for the widely used irrigation systems that rotate around a fixed center point. These systems commonly exert side load forces on the fence posts, causing either the posts or the wire strand to break or to be damaged. 
     Additionally, with large expanses of fencing, used primarily to restrain domestic livestock, ingress and egress is cumbersome, requiring a passer to open or close a conventional gate. Western style fences of barbed wire, or smooth wire mounted on wooden fence posts which often stretch for miles, require remote gates to allow ranchers or farmers access to the fenced area. When irrigation is required on part of the pasture the need for more frequent access points increases. 
     Presently, there is a need for an articulating fence post for fencing systems as well as and gating systems to facilitate passage of the irrigation system and accommodate the side loads exerted on the fence by the irrigation system. This need is especially great for fence post and gating systems which have delicate strands of electrified fencing wire which are easily snapped under the strain of an impinging irrigation system that moves along an arc that is not perpendicular to the fence line. In addition large expanses of fence posts, whether articulating or not, require gates which allows ease of ingress and egress. It would be advantageous to have a fence post for a fencing system and a gating system, which would collapse and then right itself upon passage of a vehicle or the like without damage to the fence line or the post. 
     SUMMARY OF THE INVENTION 
     It has now been discovered that the problems encountered with prior art gating for stationary and articulating fencing systems can be overcome by the present invention. In the broad aspect of the present invention, the fence post is a resilient, isotropically articulating member, which supports or facilitates gating systems for both stationary and articulating fencing systems. In accordance with the present invention, the fence posts resiliently yield to forces exerted in substantially all directions, including directions other than those perpendicular to the fence line. 
     In accordance with the broad aspect of the present invention, an isotropic fence post resiliently yields to an object (e.g., a mobile irrigation system or a ranch vehicle) approaching the fence post from any direction, even a direction substantially parallel to a fence line, as defined by the fence posts. The articulating fence post yields to objects resistively. For example, the fence post will resiliently yield to a mobile irrigation system, or in the case of an articulated gating segment, to a ranch vehicle, but not to the force of a cow moving against the fence or the gate. The resistance to a force pressing against the articulating fence or gateposts is variably set, causing the posts to substantially yield only when a preset amount of force is applied. For example, the resistance can be set such that the force of a strong wind or cows will not cause the posts to articulate, but the force of an impinging irrigation system or a ranch vehicle will cause the posts to articulate. 
     The gating system of the present invention has at least one articulating post and preferably three posts, including at least one resiliently articulating center post that is aligned between a pair of end posts, wherein a fencing material is strung between adjoining posts. The at least one center fence post of the present invention is a resilient, isotropically articulating member that preferably includes a shaft adapted for affixing flexible fencing material; a resilient, isotropically flexible member having a top end for rigid communication with the shaft and a bottom end for rigid communication with a base element; and an anchor element, permanently and immovably connected to the base element, for anchoring the base. The fencing material preferably comprises strands of wire, either single strand or braided, including strands of electrically conducting material for electric fences, and strands of barbed wire. 
     In accordance with the invention, the articulating posts can be used as fence posts or gate posts. For example, the end fence post elements of the system of the instant invention can be resiliently articulating, or they can be rigid, non-articulating supports. In one embodiment, the end fence and/or gate posts are non-articulating. It will be realized that in accordance with the invention the end post elements may also form the apex of a corner that is formed from two linear segments of fence, which are joined together at an angle (i.e., the end fence post is a corner post). At least one segment so joined can be radially articulating. 
     In accordance with the present invention, the resilient, isotropically articulating fence posts have an isotropically flexible member for allowing a shaft to resiliently articulate between a position substantially perpendicular to the ground, and a position substantially parallel to the ground. In a preferred embodiment, the isotropically articulating member is a spring, and preferably a coil spring, that is capable of radial, resilient articulation. In another embodiment, the isotropically flexible member is a segment of flexible hose, preferably made from plastic or rubber. 
     A fence material tensioning means, such as a coil spring, is used to attach a strand of fencing material to at least one post element of the gating system. The tensioning means provides flexibility to assure the integrity of the fence material when the fence is under stress. This is to further assure that strands of fencing material in the gating system will not break when the gateposts are articulated. 
     In one embodiment, the tensioning means includes at least one spring element connected at one end to a strand of fencing material and on the other to a variable set tensioning means, such as a turnbuckle, which adjusts the amount of tension on the strand. In another embodiment, the tensioning means comprises two spring segments having a variable set tensioning means there between. In another embodiment, the tensioning means comprises a spring-loaded pulley assembly rotatably attached to a post, which can be stationary or articulating depending upon the use. In accordance with this embodiment a strand of fencing material is spooled on the pulley and held in tensioned engagement therewith. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The objects, features, and advantages of the present invention will be apparent to one skilled in the art, in view of the following detailed description in which: 
     FIG. 1 is a detailed illustration of a resiliently, radially articulating post element of the instant invention; 
     FIG. 2 is an illustration of an embodiment of a resiliently, radially articulating post of the instant invention having a segment of flexible tubing; 
     FIG. 3 is a segmented illustration of the resilient, articulating fencing system using the resiliently, radially articulating posts of the instant invention; 
     FIG. 4 is a segmented illustration of the resilient, articulating gating system of the instant invention within a stationary fence; 
     FIG. 5 is a segmented illustration of the resilient, articulating gating system within a resilient, articulating fencing system using the articulating posts of the instant invention; and 
     FIG. 6 is a cutaway illustration of another embodiment of the end fence post of the instant invention having spring-loaded pulleys for resiliently tethering the fence strands. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIG. 1, the resiliently articulating fence post  14  is comprised of a shaft  26  having, for example, at least one aperture  28  adapted to receive strands of fencing material  16  wherein the lower end of the shaft  26  is immovably affixed to spring  30 , which allows shaft  26  to articulate from a normally upright positions to positions substantially parallel with the ground. The shaft may be made from materials such as metal, wood, plastic or fiberglass. The spring  30  is resilient, so once the force is removed that holds the shaft  26  parallel with the ground, the shaft  26  and spring  30  automatically return to an upright position, substantially perpendicular to the ground. 
     The lower end of the spring  30  is immovably attached to the topside of the base  32 . The base  32  includes hollow tube  34 , which accepts stake  36  that is driven into the ground in order to immovably anchor the post  14  to the ground. A threaded aperture (not shown), formed in the side of tube  34 , accepts a threaded shaft  38 , attached to an actuator handle  40 . The threaded shaft  38  is tightened to engage stake  36  with the actuator handle  40 , in order to immovably fix the stake  36  to the base  32 . In another embodiment (not shown) base  32  is outfitted with a one way jaw means for automatically engaging stake  36  to hold the base  32  to engaging stake  36 . A pair of rigid collars  42  are formed on the base  32  proximate the spring  30 . The rigid collars  42  act to guide the direction of the shaft  26  as it articulates up and down between an upright position and the ground. 
     Referring now to FIG. 2, another embodiment of the resiliently radially articulating post  114  is shown. In this preferred aspect, the bottom end of the shaft  126  is inserted into the isotropically flexible member  134  which comprises a segment of resilient, isotropically flexible tubing. The shaft  126  is normally positioned upright in tubing  134 , and can radially articulate from this upright position to a substantially flattened position proximate the ground. Since the tubing  134  is resilient, the shaft  126  will automatically return to an upright position when the articulating force is removed. 
     The lower end of the tubing  134  is attached to the topside of the base  132 . The base  132  is immovably anchored to the ground by a stake  136 , attached to the bottom of the base  132 . The stake  136  may be formed with fins (not shown), so called a T-Post, which make the stake easy to drive into the ground, but difficult to extract from the ground. The shaft  126  has at least one aperture  128 , which is adapted to accept strands of fencing material. Three apertures  128  are shown in FIG. 2, located proximate to the top end of the shaft  126 , and each aperture  128  runs through the shaft  126  perpendicular to the long axis of the shaft  126 . The apertures  128  are adapted to allow the fencing strand material to pass there through. 
     In operation the radially articulating posts are incorporated into, for example, a fencing system as illustrated in FIG. 3. A fencing system  10  employs stationary end posts  12  having, respectively, tensioning assemblies  18 . The system  10  employing posts  14  allows the fence system  10  to articulate allowing passage of the desired device e.g. an irrigation device or other machinery, when an external force of sufficient magnitude is exerted on the fencing system  10 . When presented with a force sufficient to offset the preset force on posts  14 , these resiliently, radially articulating posts  14  articulate towards the ground from their normally upright positions. The strain placed on the fencing material  16  when the shafts  26  articulate towards the ground is reduced by stretching the length of the first and second spring segments,  20  and  22 , thus providing slack or “give” to the system  10  to prevent the displaced fencing material  16  from breaking. When the external force is removed, the resilient shaft  26  articulates back to its fully upright positions, and the first and second springs,  20  and  22 , contract to re-tension the fencing material  16 , to keep it taut. It will be realized that any resilient device allowing for selected displacement and subsequent re-tensioning of the fencing material may also be used. 
     Referring now to FIG. 4, there is shown gated portion  344  of the instant invention of a fencing system represented by stationary fence posts  312  having strands of fencing material  316  strung between posts  312 . The gated portion  344  includes resiliently, radially articulating, gate posts  346  having strands of fencing material  316  strung between posts such that the gate posts  346  and the stationary posts  312  form a fenced continuum. The fencing material  316  may be made from barbed wire, smooth wire, or wire for electrification. 
     The lower end of the shaft  326  is immovably affixed to spring  330 , which allows shaft  326  to articulate from a normally upright position to positions substantially parallel with the ground. The spring  330  is resilient, so once the force is removed that holds the shaft  326  parallel with the ground, the shaft  326  and spring  330  automatically return to an upright position, substantially perpendicular to the ground. 
     The lower end of the spring  330  is immovably attached to the topside of the base  332 . The base  332  includes hollow tube  334 , which accepts stake  336  that is driven into the ground in order to immovably anchor the post to the ground. A threaded aperture (not shown), formed in the side of tube  334 , accepts a threaded shaft, attached to an actuator handle  340 . The threaded shaft is tightened to engage stake  336  with the actuator handle  340 , in order to immovably fix the stake  336  to the base  332 . In another embodiment (not shown) base  332  is outfitted with a one-way jaw means for automatically engaging stake  336  to hold the base  332  to engaging stake  336 . A pair of rigid collars  342  is formed on the base  332  proximate the spring  330 . The rigid collars  342  acts to guide the direction of the shaft  326  as it articulates up and down between an upright position and the ground. 
     In FIG. 4, stationary posts  312  are arranged colinearly between aligned, resiliently radially articulating gate posts  346 . Each fence post  312  is attached to a tensioning means  318 , which is in turn attached to the strands  316 . The tensioning means  318 , which provides slack to the strands of fencing material  316  so as not to snap the wire when the resiliently radially articulating center gating system posts  346  articulate, comprises a first spring segment  320  and a second spring segment  322  which are connected at their respective ends by a turnbuckle  324 . The first spring segment  320  is attached on its other end to the end posts  312  at tensioning means  318 , and the second spring segment  322  is attached at its other end to the strands of fencing material  316 . The amount of tension on the strands of fencing material  316  can be adjusted by tightening or loosening the tension in the strands of fencing material  316  by means of turnbuckles  324  in a conventional manner. 
     The lower end of the shaft  426  is immovably affixed to spring  430 , which allows shaft  426  to articulate from a normally upright position to positions substantially parallel with the ground. The spring  430  is resilient, so once the force is removed that holds the shaft  426  parallel with the ground, the shaft  426  and spring  430  automatically return to an upright position, substantially perpendicular to the ground. 
     The lower end of the spring  430  is immovably attached to the topside of the base  432 . The base  432  includes hollow tube  434 , which accepts stake  436  that is driven into the ground in order to immovably anchor the post to the ground. A threaded aperture (not shown), formed in the side of tube  434 , accepts a threaded shaft, attached to an actuator handle  440 . The threaded shaft is tightened to engage stake  436  with the actuator handle  340 , in order to immovably fix the stake  436  to the base  432 . In another embodiment (not shown) base  432  is outfitted with a one-way jaw means for automatically engaging stake  436  to hold the base  432  to engaging stake  436 . A pair of rigid collars  442  is formed on the base  332  proximate the spring  330 . The rigid collars  442  acts to guide the direction of the shaft  426  as it articulates up and down between an upright position and the ground. 
     Referring now to FIG. 5, there is shown a gating system  444  of the instant invention within a resiliently radially articulating fence system. The fencing system has end stationary posts  412 , resiliently radially articulating posts  414 , and gate posts  446  which form a gated portion  444 . Strands of fencing material  416  are strung between the posts  412 ,  414 , and  446 . The fencing material may be made from barbed wire, smooth wire, or wire for electrification. 
     In FIG. 5, stationary end posts  412  are arranged colinearly with aligned, resiliently radially articulating posts  414 , which are in turn colinearly aligned with gateposts  446 . Each fence post  412  is attached to a tensioning means  418 , which is in turn attached to the strands  416 . The tensioning means  418 , which provides slack to the strands of fencing material  416  when the resiliently radially articulating gating system posts  446  articulate, comprises a first spring segment  420  and a second spring segment  422  which are connected at their respective ends by a turnbuckle  424 . The first spring segment  420  is attached on its other end to the posts  446  at tensioning means  418 , and the second spring segment  422  is attached at its other end to the strands of fencing material  416 . The amount of tension on the strands of fencing material  416  can be adjusted by tightening or loosening the tension in the strands of fencing material  416  by means of turnbuckles  424 . The gated segment  444  employs multiple tensioning means  418  as illustrated to provide the slack within the fencing system to selectively allow a truck car or the like to pass over the gated section  444 . 
     Referring now to FIG. 6, another embodiment of a tensioning means, affixed to an end post, is illustrated as  200 . As shown, fixed end post  212  carries a series of tensioning means  218  comprising a rotatable, spring loaded pulley  220 , rotatably secured through their center to the end fence post  212  by means of fasteners  222 , such as, pins, bolts or screws. Fencing material  216  is fixedly attached to the pulleys  220  and spooled thereon such that the spring-loaded pulley tensions the fencing material. When the strands of fencing material  216  come under stress as resiliently articulating center posts (not shown) flex towards the ground, the pulleys  220  play additional fencing material  216  to reduce the strain. It will be realized that the system  200  can be used with the gated portion of the fence system in accordance with the invention. In another embodiment, any resilient device allowing for the play of fencing material  216  may also be used. When the resilient articulating center posts (not shown) return to their upright position, the pulleys  220  automatically “reel” in the slack in the fencing material  216 , keeping the strands of fencing material  216  taut along the length of the fence system  200 . It will be realized that the strands of wire are a matter of preference or use and not limited to a specific number, material, or method of attachment. 
     The flexible gating system and fence posts of the present invention have been exemplified with reference to the various aspects and examples described and illustrated above. By using the description of the present invention found herein, one skilled in the art may be able to design other versions of the flexible fence system, and its component parts, which differ from those illustrated. However, the present invention is not intended to be limited to only the described aspects and examples. Rather, the following claims, and all equivalents of these claims, define the scope of the present invention.