Fencing apparatus and fencing techniques

Abstract

The potential capabilities, and actual performance, of modern fencing have been much improved by the introduction of high tensile wire due to its ability to hold a considerable strain without stretching. high tensile fencing wire has a yield strength of approximately 1650 MPa and an ultimate strength of 1860 MPa. Such high tensile fencing wires are installed with a tension of approximately 2 kN and have a breaking strain of approximately 8 kN. However, this strength advantage comes with an associated property in that the wire is not at all malleable, being very stiff and hard to bend. In addition, modern high tensile wire is provided with a thin anti-corrosion coating which substantially increases the economic life of the wire. A wire tensioning device (100) is disclosed having a cross member (104), a pair of handles (120, 121) pivoted to the cross member and movable between open and closed positions, a stationary stud (115) substantially centrally located on the cross member, and a pair of roller pins (116, 117 and 118, 119) located on each of the handles. With the handles open the roller pins are substantially aligned to permit a substantially straight length of high tensile wire (123) having an anti-corrosion coating to be located between the roller pins. Conversely, with the handles closed be roller pins are misaligned to bend the length of wire into a shortened substantially W-shaped configuration. This wire movement rotates the roller pins to preserve the anti-corrosion coating. A method of tensioning high tensile wire(s) installed in a fence is also disclosed. This involves forming at least one of the wires into a substantially W-shape by moving a plurality of pin rollers engaged with the wire, the deformation of said wire rotating the pin rollers to thereby reduce damage to an anticorrosion coating on said high tensile wire(s).

Description

“FENCING APPARATUS AND FENCING TECHNIQUES”Field of the InventionThe present invention relates to fencing, and in particular, to fencing apparatus which is of assistance to fencers and farmers in repairing existing fencing.Background ArtThe potential capabilities, and actual performance, of modern fencing have been much improved by the introduction of high tensile wire due to its ability to hold a considerable strain without stretching. For example, low tensile wires such as “soft” malleable fencing wire and similarly malleable wires such as bailing wire, typically have a yield strength in the range of approximately 350-550 MPa. Similarly, low tensile fencing wire is typically installed with a tension of approximately 1 kN and has a breaking strain of approximately 3kN.By contrast, high tensile fencing wire has a yield strength of approximately 1650 MPa and an ultimate strength of 1860 MPa. Such high tensile fencing wires are installed with a tension of approximately 2 kN and have a breaking strain of approximately 8 kN. However, this strength advantage comes with an associated property in that the wire is not at all malleable, being very stiff and hard to bend. In addition, modern high tensile wire is provided with a thin anti-corrosion coating which substantially increases the economic life of the wire.Fences generally take the form schematically illustrated in Fig. 1, and in such a fence any of the horizontally extending wires is liable to be stretched by farm animals, wildlife, feral animals, and the like. In the event of such stretching it is necessary for the fence to be re-strained. Unless the fence can be re-strained to a tension approaching its original condition, the fence is not likely to be as effective as desired.However, often the stretching does not warrant a complete re-straining of the fence using fence strainers. For this reason, it is known to insert spool or bobbin devices in individual wires of the fence and onto which a length of wire is wound. This enables the tension in the corresponding wire to be increased to the desirable degree. One variety of this type of device is sold in Australia under the name TWfTCHER. Another is that disclosed in US Patent No 4, 485, 852 (Frazier).Such devices suffer from the problem that the spool or bobbin devices represent a financial outgoing and must also be available to the farmer to enable the tension in the wire to be increased. Often the farmer will find that he is out of stock of such devices when a repair is required.Genesis of the InventionThe Genesis of the present invention is a desire to provide fencing apparatus and fencing techniques which can be of assistance in relation to the creating and maintaining of fences utilising high tensile wire.Summary of the InventionIn accordance with a first aspect of the present invention there is disclosed a wire tensioning device comprising a cross member, a pair of handles pivoted to said cross member and movable between open and closed positions, a stationary stud substantially centrally located on said cross member, and a pair of roller pins located on each said handle, wherein with said handles open said roller pins are substantially aligned to permit a substantially straight length of high tensile wire having an anticorrosion coating to be located between said roller pins, and with said handles closed said roller pins are misaligned to bend said length into a shortened substantially W-shaped configuration, whereby said wire movement rotates said roller pins.In accordance with another aspect of the present invention there is disclosed a method of tensioning high tensile wire(s) installed in a fence, said method comprising the step of forming at least one of said wires into a substantially W-shape by moving a plurality of pin rollers engaged with said one wire, the deformation of said wire rotating said pin rollers to thereby reduce damage to an anticorrosion coating on said high tensile wire(s).Brief Description of the DrawingsAn embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:Fig. 1 is a schematic side elevation of a typical conventional fence known to the prior art;Figs. 2 and 3 reproduce drawings from US Patent No 2,087,125 and are side elevations of the prior art device of that patent;Fig. 4 is a schematic perspective view of a device of the preferred embodiment;Fig. 5 is a vertical cross-sectional view through one of the roller pins of Fig. 4; andFig. 6 is a schematic side elevation showing a fence as in Fig. 1 but after undergoing creation of tension increasing crimps or wrinkles.Detailed DescriptionAs seen in Fig. 1, a typical fence 1 takes the form of a strainer post 2 and star pickets3. A typical arrangement consists of two upper wires 5, 6 of barb wire, and up to three wires which support hinge lock 11, ring lock or similar wire mesh materials. These three wires are respectively a top wire 7, a belly wire 8 and a bottom wire 9. The hinge lock 11 typically has eight horizontal wires with the uppermost wire being clipped to the top wire 7, the bottommost wire being clipped to the bottom wire 9, and one of the intermediate wires being clipped to the belly wire 8.As an addition to, or an alternative to, the hinge lock 11, wire netting 12 can be used, particularly if a rabbit proof fence is desired.It will be apparent that any of the horizontally extending wires of the fence 1 can be stretched by stock, wildlife, or feral animals. Somewhat paradoxically, the bottom wire 9 is often stretched by kangaroos which push under the fence 1, notwithstanding their ability to jump over the fence 1 if they felt so inclined. Once the bottom wire 9 is stretched by a kangaroo or wild pig, then a passage becomes established and this can lead to the misplacement or even loss of sheep, calves, etc. by their passing through the fence 1.Whilst the bottommost wire of the hinge lock 11 might be under a desired tension, because this wire does not pass through the posts of the fence but lies alongside them, this wire can deflect upwardly to permit the passage of an animal underneath. However, the bottom wire 9 is passed through the holes in the posts of the fence and therefore must be stretched in order to permit the passage of an animal underneath. It is therefore very desirable to maintain the tension in the bottom wire 9.US Patent No 2, 087, 125 (Smith filed 1936) discloses a manual wire tightening device 1, which as see in Figs. 2 and 3, has a cross head 4 with two handles 20, 21 pivoted thereto by means of bolts 7, 8. There is a stationary stud 15 on the cross head 4 positioned between the two handles. Handle 20 carries a pair of studs 16, 17 whilst handle 21 carries a pair of studs 18, 19. With the handles open, a soft wire 23 can be located intermediate the studs 15-19 so that closing the handles bends the wire 23 into a crimp or wrinkle 30 of approximately W shape. This shortens the wire 23 and so increases the tension in the wire.During this deformation of the wire, the wire 23 is crimped without being elongated and so the wire slides relative to the studs 16, 17 and 18, 19. With uncoated soft wire as existed in 1936, this sliding action did not represent any problem and was easily accommodated.However, modem high tensile fencing wire is provided with a thin corrosion resistant coating and it is highly desirable that this coating not be damaged either during initial installation of fence, or during repairs to the fence. Damage to the coating permits the high tensile wire to rapidly corrode.As seen in Fig. 4, a manual wire tightening device 100 of the preferred embodiment has a cross head 104 with two handles 120, 121 pivoted thereto by means of bolts 107, 108. There is a stationary stud 115 on the cross head 104 positioned between the two handles. Handle 120 carries a pair of roller pins 116, 117 whilst handle 121 carries a pair of roller pins 118,119. Roller pins 111 and 112 are located on the cross head 104. A stud 105 on the cross head 104 provides a limit to the closing action of the handles 120, 121.With the handles open, a high tensile wire 123 can be located intermediate the roller pins 111-119 so that closing the handles bends the wire 123 into a crimp or wrinkle of approximately W shape. This shortens the wire 123 and so increases the tension in the wire.During this deformation of the wire, the wire 123 is crimped without being elongated and so the wire 123 slides relative to the roller pins 111, 112, and 116, 117 and 118, 119.As seen in Fig. 5, each of the roller pins 111-119 consists of a threaded shaft 140 having a button head 141. Located beneath the button head 141 and around the shaft 140 is a thin-walled cylinder 142, preferably fabricated from brass or stainless steel. It will be apparent that during the deformation of the wire 123, the wire is able to rotate the cylinder 142 and therefore the crucial anti-corrosion coating on the exterior of the high tensile wire 123 is not damaged during this operation.Fig. 6 illustrates the fence of Fig. 1 after undergoing various applications of the wire tightening device 100 so as to create crimps or wrinkles 200. These can be applied either to barbed wires 5, 6 or to plain wires 7, 8, 9 or to wires within the hinge lock 11. It is desirable to place the crimps or wrinkles 200 approximately centrally in each panel of the fence for aesthetic reasons.Where it is intended to crimp a length of barbed wire, it is desirable to align the stationary stud 115 with one of the barbs. This therefore locates the W-shaped wrinkle 200 symmetrically about that one barb.Furthermore, with reference to Fig. 6, a wrinkle 200 can be put into the wire 8 from which the rabbit netting 12 hangs by the simple expedient of turning the device 100 upside down so that the pins 116, 117, 118, 119 face downwardly.Still further, the wrinkles 200 are able to pass through the holes of a standard steel star picket 3 which therefore enables the fence 1 to be dismantled or re-strained if desired. This is to be contrasted with some other re-straining devices such as that disclosed in Australian Innovation Patent No 2015 100 311 (Quattromani) which require an additional piece of wire to be placed alongside the wire to be re-strained.The foregoing describes only one embodiment of the present invention and modifications, obvious to those skilled in the fencing arts, can be made thereto without departing from the scope of the present invention. For example, the shaft 140 of each of the roller pins 111-119 can be connected to the cross head 104 or handles 120, 121 by means such as welding, brazing or even being forged simultaneously therewith.The term “comprising” (and its grammatical equivalents) as used herein is used in the sense of “having” or “including” and not in the sense of “consisting only of’.

Claims

CLAIMS1. A wire tensioning device comprising a cross member, a pair of handles pivoted to said cross member and movable between open and closed positions, a stationary stud substantially centrally located on said cross member, and a pair of roller pins located on each said handle, wherein with said handles open said roller pins are substantially aligned to permit a substantially straight length of high tensile wire having an anti-corrosion coating to be located between said roller pins, and with said handles closed said roller pins are misaligned to bend said length into a shortened substantially W-shaped configuration, whereby said wire movement rotates said roller pins.

2. The device as claimed in claim 1 and comprising a further two of said roller pins located on said cross member, one to either side of said handles.

3. The device as claimed in claim 1 or 2 wherein each said roller pin comprises a shaft, a head on said shaft, and a substantially cylindrical sleeve rotatably mounted on said shaft.

4. The device as claimed in claim 3 wherein said sleeve is fabricated from metal.

5. The device as claimed in claim 4 wherein said metal is selected from the class consisting of brass and stainless steel.

6. A method of tensioning high tensile wire(s) installed in a fence, said method comprising the step of forming at least one of said wires into a substantially W-shape by moving a plurality of pin rollers engaged with said one wire, the deformation of said wire rotating said pin rollers to thereby reduce damage to an anticorrosion coating on said high tensile wire(s).Dated this 11th day of November 2019WIREMAN PTY LTDBy its Patent AttorneysFRASER OLD & SOHNPRIOR ART

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