Field of the Invention

The present invention relates to agricultural fencing and, in particular, to raising the height of agricultural fencing, to fence posts, to droppers, to coupling tubes, to cantilever arms, and to clips for agricultural fences.

Background Art

Many agricultural fences utilise tricuspid steel posts which may have a Y or a T transverse cross-sectional shape. Traditionally such steel posts are spaced about 4-5 m apart and normally there are a series of panels denoted by wooden, and sometimes concrete, posts with approximately four or five steel post between each pair of wooden or concrete posts.

In recent times a steel post of increased thickness, but the same Y-shape, has been used and these posts are sufficiently strong to enable the wooden or concrete posts to be dispensed with. That is, apart from the strainer post, or end assembly, at each end, the fence uses the same steel posts along its entire length. Such increased thickness posts are sold in Australia under the Registered Trade Marks BEEFY (Clipex) or MaxY (Waratah).

Such fences are intended to keep domestic stock in and are not overly concerned about wild animals such as dingoes, wild dogs, kangaroos or deer. Such fences, termed inclusion fences, are approximately waist high being typically approximately 1.2 m in height. Such fences are built from posts having a length of approximately 1.8 m which are driven into the ground approximately 600 mm.

However, recently another form of fence, termed an exclusion fence, has been constructed and these are of approximately head height being typically 1.8 m in height and are intended to exclude the above-mentioned wild animals.

The dilemma for the farmer having an inclusion fence is that in order to achieve the functionality of an exclusion fence, it was until very recent times necessary to erect a new fence using lengthy steel posts intended for head high use. Such posts are typically approximately 2.4 m long and are driven into the soil approximately 600 mm deep. This can be a difficult task to undertake without specialised equipment. Such posts, and rolls of netting which are approximately 1.8 m high, are very expensive, heavy and awkward to handle without expensive specialised machinery.

One approach to overcoming this dilemma is to increase the height of the existing fence. International Patent Application Nos WO 2016/019436 (Cameron French) and WO 2021/000012 (Wireman Pty Limited) illustrate two fencing arrangements which enable a fence post extension to be erected above an existing fence post. Such fence post extensions are typically approximately 600 mm in length so that a waist high fence approximately 1.2 m high can be raised in height to just under 1.8 m.

However, there are many circumstances where a fence height of 1.8 m is not actually high enough to prevent kangaroos and/or deer from jumping over the fence. Such animals are known to jump over fences 2 m high. In order to achieve extra height, it is desirable to use an additional fence post, not merely a fence post extension, coaxially installed above each existing fence post, in order to achieve the necessary height. US Patent No 5, 395, 093 (Christman) discloses a connecting or coupling tube or sleeve which enables the coaxial interconnection of two such fence posts.

Furthermore, Australian Innovation Patent No. 2021 107 322 (InfraBuild Wire Pty Limited) discloses a two-part assembly which enables two Y -shaped posts to be bolted together in an end-to-end coaxial arrangement. This proposal requires both adjustment of the top wire(s) of the existing waist high fence and for the upper post to be held in position during the bolting procedure. A further problem with this arrangement is that the uppermost holes of the lower fence post and the lowermost holes of the upper fence post, are occupied by the bolts joining the post together. As a consequence, there is a difficulty in locating any wires close to the join and a horizontally extending gap in the fence at approximately waist height is often the result.

Droppers are widely used to maintain the spacing between horizontal wires in a fence, particularly where the fence crosses over patches of rocky ground and therefore conventional fence posts such as steel star pickets cannot be driven into the ground. Droppers are also used in lieu of star pickets as an economy measure where, for example, every second star picket is sometimes replaced by a dropper. Australian Patent Application Nos 55838/73; 16620/83; 48953/85; 20939/92 and 45872/96 are indicative of this art.

Agricultural fences consisting of a series of spaced apart, parallel, substantially vertical metal posts, or pickets have various horizontally extending wires connected to the pickets. Normally the pickets include prefabricated holes. A clip formed from a piece of wire having two ends is used to retain the horizontally extending wires to the posts. Normally this is done by engaging a respective wire end of the clip with a corresponding one of a pair of holes in the post.

Australian Innovation Patent No 2021 107 345 entitled Post Retainer and Australian Registered Design No 2021 15397 entitled Post Clip, both in the name of InfraBuild Wire Pty Limited; Australian Patent Application No 2021 218 235 entitled Fence Clip and Australian Design Registration No 2021 13779 entitled Fence Clip both in the name of Southern Wire Pty Ltd; and Australian Design Registrations Nos 2017 17729 and 2019 17384 both in the name of Austral Wire Products Pty Ltd, exemplify this art.

Genesis of the Invention

The Genesis of the present invention is a desire to provide an improved fencing system.

Summary of the Invention

In accordance with a first aspect of the present invention there is disclosed a multifunction fence post component for use with elongated tricuspid fence posts, each of said fence posts having a generally Y-shaped or T-shaped transverse cross- sectional shape in which said Y comprises a stem and two V arms each of which has an outer edge and said T comprises a stem and crosspiece having two outer edges, said multifunction fence post component comprising an elongate sleeve having a longitudinal axis, said sleeve having a generally C-shaped transverse cross-sectional configuration with a shallow V-shaped back portion having two flanks each of which terminates in an acute V-shaped elbow having a free arm extending therefrom, said free arms extending towards each other and forming a longitudinally extending open mouthed slot dimensioned to receive said fence post stem, and the distance between said elbows being dimensioned to receive said fence post outer edges.

Preferably the multifunction fence post component can be a coupling tube for joining two elongated tricuspid fence posts end to end, a fence post extender, a fence post, and/or a dropper.

Preferably where the component is a coupling tube intended to couple together fence posts of different sizes, then the component can take the form of an aligned pair of coupling tubes of different sizes.

Preferably the fence post(s) is/are symmetrical about said stem and said component has a first axis of symmetry extending between said flanks and a second axis of symmetry extending between said elbows.

In accordance with a second aspect of the present invention there is disclosed a method of rolling the component as defined in the above paragraph, said method comprising the steps of: if necessary, stamping a length of strip sheet steel to create any desired apertures therein, passing said strip through a first centrally located roller means to form said shallow V-shaped back portion, simultaneously passing said strip through a pair of spaced apart roller means to simultaneously form both said free arms and said acute V-shaped elbows, and docking said strip to a desired length.

According to another aspect of the present invention there is provided a method of extending the height of a first, lower, tricuspid fence post having a generally Y or T- shaped transverse cross-sectional configuration by co-axially locating a second, upper, like fence post thereabove, said method comprising the steps of: locating a lower portion of a coupling tube as defined above on the upper end of said lower post, retaining said coupling tube lower portion in position by abutment of a protrusion of said tube with the top of said lower post, and locating said like post within the upper portion of said coupling tube.

In accordance with a still further aspect of the present invention there is disclosed a method of extending the height of a first, lower, tricuspid fence post having a generally Y-shaped transverse cross-sectional configuration by coaxially locating a second upper, similar fence post thereabove, said second fence post being more slender than said first post, said method comprising the steps of: locating a lower portion of a first coupling tube as defined above and dimensioned to mate with said first post, on the upper end of said first post, retaining said first coupling tube lower portion in position by abutment of a protrusion of said first tube with the top of said lower post, locating an upper portion of a second coupling tube as defined above and dimensioned to mate with said second post, on one end of said second post, and locating a lower portion of said second coupling tube in the upper end of said first coupling tube.

In accordance with yet another aspect of the present invention there is disclosed a tricuspid fence post of substantially Y-shaped configuration and having a pointed tip, wherein a circular aperture is formed in said post closely adjacent said tip.

In accordance with yet another aspect of the present invention there is disclosed an internal strut used to support in cantilever fashion a fence component as defined above, said strut comprising a substantially rectangular strip curved about its longitudinal axis into a generally C-shaped configuration and curved transversely into a substantially V-shaped configuration.

In addition, there is disclosed a vertical strut to support a pair of cantilever arms having a V-shaped configuration, said strut being elongate and having a longitudinal axis, and this being slit along said axis at its upper end to form two tabs which are bent or curved away from said axis.

In accordance with a still further aspect of the present invention there is disclosed a agricultural fence clip fabricated from wire and comprising a helical torsion spring having at least one turn and a longitudinal axis, and a pair of arms; each of said arms extending from a corresponding end of said torsion spring and terminating in a reentrant hook, and the torsion spring when viewed along said longitudinal axis appearing at the apex of a V formed from said arms.

Brief Description of the Drawings

Preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Fig. 1 is a perspective view of the coupling tube of a first embodiment,

Fig. 2 is a side elevation of the coupling tube of Fig. 1,

Fig. 3 is a transverse cross-sectional view through the line III-III of Fig. 2,

Fig. 4 is an end view of the coupling tube of Fig. 1 located on a conventional star picket,

Fig. 5 is an end view similar to Fig. 4 but of a coupling tube of a second embodiment suitable for larger size star pickets,

Fig. 6 is a plan view of the flat sheet metal strip from which the coupling tube is to be rolled,

Fig. 7 is an end view of the sheet metal strip showing in a schematic fashion the initial stages of the rolling procedure,

Fig. 8 is a view similar to Fig. 7 and showing in schematic fashion the final stages of the rolling procedure,

Fig. 9 is a side elevation of a conventional star picket,

Fig. 10 is a side elevation showing the coupling tube joining two conventional star pickets in a first fashion,

Fig. 11 is a side elevation similar to Fig. 10 showing the coupling tube joining two conventional star pickets in a second fashion,

Fig. 12 is a side elevation of a conventional T-post as used in the USA,

Fig. 13 is a side elevation showing two T-posts being coupled together,

Fig. 14 is a plan view of the two coupled T-posts of Fig. 13,

Fig. 15 is a perspective view of the two coupled T-posts,

Fig. 16 is a side elevation showing a small star picket coupled to a large star picket,

Fig. 17 is a top end view of the two coupled star pickets of Fig. 16, Fig. 18 is a perspective view of the two coupled star pickets of Fig. 16,

Fig. 19 is another perspective view of the two coupled star pickets of Fig. 16,

Fig. 20 is a view similar to Figs. 3 - 5 and of a coupling tube of wide commercial application,

Fig. 21 is a perspective view of a fence post or dropper of indefinite length,

Fig. 22 is a first end view of the fence post or dropper,

Fig. 23 is a first side view of the fence post or dropper,

Fig. 24 is a plan view of the fence post or dropper,

Fig. 25 is an inverted plan view of the fence post or dropper,

Fig. 26 is a second side view, opposite to the first side view, of the fence post or dropper,

Fig. 27 is a second end view, opposite to the first end view, of the fence post or dropper,

Fig. 28 is a perspective view of the tip of a modified Y-shaped star picket of indefinite length including a small circular wire receiving opening adjacent the tip,

Fig. 29 is a perspective view of a coupling sleeve of a further embodiment,

Fig. 30 is a perspective view of a rectangular strip of steel from which an internal strut can be formed,

Fig. 31 is a perspective view of the strip of Fig. 30 formed into a V- configuration,

Fig. 32 is a truncated perspective view of the strut of Fig. 31 being used to support a length of fence post or dropper at an angle inclined to the horizontal so as to form the upper portion of an exclusion fence,

Fig. 33 is an exploded perspective view of the upper portion of an exclusion fence having two inclined portions supported by a generally Y -shaped internal strut,

Fig. 34 is a side elevation of the Y-shaped internal strut of Fig. 33,

Fig. 35 is an end elevation of the Y-shaped internal strut of Fig. 33,

Fig. 36 is an inverted perspective view of a further embodiment of the V- shaped strut of Fig. 31, Fig. 37 is a perspective view from one side of an upright joiner for use with the V-shaped strut of Fig. 36,

Fig. 38 is a perspective view from the other side of the upright joiner of Fig. 37,

Fig. 39 is a perspective view of the upright joiner of Figs. 37 and 38 supporting the V-shaped strut of Fig. 36 in an upright manner, and Fig. 40 is a perspective view of the upright joiner of Figs. 37 and 38 supporting the V-shaped strut of Fig. 36 in an inverted manner, Fig. 41 is a perspective view of a cantilever strut of a further embodiment, Fig. 42 is a perspective view of a vertical strut which has a longitudinally extending slit and is able to cooperate with the cantilever strut of Fig. 41, Fig. 43 an exploded perspective view showing the inter-engagement of the struts of Figs. 41 and 42,

Fig. 44 is a similar perspective view but showing the completed interengagement,

Fig. 45 is a perspective view from one side showing a vertically slit vertical strut of another embodiment,

Fig. 46 is a perspective view from the other side of the strata of Fig. 45,

Fig. 47 is a perspective view showing the inter-engagement of the vertical strut of Figs. 45 and 46 with the inverted cantilever strut of Fig. 41,

Fig. 48 is a perspective view of a strainer post of a waist high fence and on which an elevated strainer post is to be installed,

Fig. 49 is a perspective view of the strainer post of Fig. 48 upon which a heavy duty star picket is being installed,

Fig. 50 is a perspective view of the finished installation.

Fig. 51 is a perspective view of the agricultural fence clip of a first embodiment,

Fig.52 is an elevational view of one end of the clip of Fig. 51,

Fig. 53 is a side elevation of one side of the clip of Fig. 51,

Fig. 54 is a side elevation of the other side of the clip of Fig. 53,

Fig. 55 is an end view of the other end of the clip of Fig. 52, Fig. 56 is a plan view of the clip of Fig. 51,

Fig. 57 is an inverted plan view of the clip of Fig. 56, Fig. 58 is side elevational view of an agricultural fence of increased height, the wires being held in place on the fence post extension by means of the clip of Fig. 51, Fig. 59 is a schematic perspective view of the upper portion of the post illustrated in Fig. 58 showing the interconnection of the clips and the fence post extension,

Fig. 60 is a vertical elevation of a strained horizontal wire with which the clip of Fig. 51 is about to be connected,

Fig. 61 is a vertical elevation of the wire of Fig. 60 to which the clip of Fig. 51 has been connected, and

Fig. 52 is a perspective view similar to that of Fig. 51 but showing the agricultural fence clip of a second embodiment.

Detailed Description

As seen in Figs. 1-3, the coupling tube 10 of the first preferred embodiment takes the form of a steel strip which is rolled into a sleeve having a lozenge like configuration when viewed in cross-section. The tube has a longitudinal axis 11 and a longitudinally extending open mouthed slot 13 so that the transverse cross-sectional configuration resembles the letter C.

The tube 10 has a back portion 14 which has two flanks 15, 16 between which is a shallow V-shaped bend 17 of approximately 120° and preferably lying within the range of 110-150°. Extending away from the bend 17, the flanks 15, 16 respectively terminate in two corresponding acute V-shaped elbows 21, 22, each of which has a corresponding free arm 24, 25. The V shaped elbows 21, 22 have a bend of approximately 60° and preferably lying within the range of 50-80°. The free arms 24, 25 each terminate in a corresponding edge of the slot 13.

As is apparent from Figs. 4 and 5, the coupling tube comes in two sizes, the smaller size tube 10 being dimensioned to mate with a conventional Y-shaped star picket 40 and the larger tube size 100 being dimensioned to mate with the larger more recent Y- shaped BEEFY or MaxY style star picket 41. The corresponding angles for the larger star picket 41 are the acute V being approximately 60° and preferably lying within the range of 50 -70°, whilst the shallow V-shaped bend is approximately 120° and preferably lying within the range of 110 -150°.

As is also apparent from Figs. 4 and 5, the coupling tube 10 when viewed in transverse cross-section has two axes of symmetry or reflection. The first axis of symmetry extends vertically up and down the page between the flanks and is aligned with the stem 40, 41 of the star pickets. A second axis, but of partial symmetry or reflection, extends from left to right across the page and is aligned with the elbows 21, 22.

As illustrated in Fig. 1, the tube 10, 100 can be provided with one or more apertures 27 in one, or both, of the flanks 15, 16. The aperture 27 is sized to retain a fastener in the form of a TEK screw 28. A conventional rivet (not illustrated) can also be used in place of the screw 28. The object of this fastener is to provide a protrusion into the hollow interior 19 of the tube 10, 100 which retains the tube 10, 100 in place when positioned on the star picket or other post.

Turning now to Figs. 6-8, the tube 10, 100 is fabricated from flat strip steel material 34 which is initially punched in order to provide apertures such as apertures 27 in the finished product and at the desired aperture locations. Thereafter, the strip is passed through a series of rolls or rollers 35, 36 which transform the strip 34 in a number of stages from a flat configuration into the C-shaped configuration illustrated in Fig. 3. As schematically illustrated in Figs. 7 and 8, each of the roller series 35, 36 takes the form of a number of individual rollers which progressively transform the strip 34 in the desired manner. This is a conventional roll forming technique. Thereafter the rolled strip 34 is cut, or docked, so as to form the desired length of the coupling tube 10, 100.

Turning now to Fig. 9, a star picket 40 or 41 is illustrated having a notch 42 and a tang 43 at its upper end and a series of apertures 44 formed in its stem 46. The lowermost one of the apertures 44 generally indicates the approximate depth to which the post 40, 41 should be driven into the soil. At least one brand of star picket 40, 41 is also provided with a large generally elliptical aperture 47 adjacent its tip. This aperture is intended to enable the posts to be securely connected to each other for shipment prior to installation. The aperture 47 is normally underground and therefore is not intended to be utilised to string wire.

Fig. 10 illustrates an existing conventional star picket 40 already positioned in a fence (not illustrated but a conventional waist high fence) and onto which has been slid the lower end 51 of a coupling tube 10. This sliding action comes to an end when the screw 28 abuts the upper end of the post 40. With the coupling tube 10 thus positioned on the post 40, a like post 40 is able to be slid into the upper end 52 of the coupling tube 10. This brings the lowermost point 48 of the upper post 40 into contact with the fastener 28 and/or the upper end of the existing lower fence post 40. As a consequence, the upper, like, post 40 is held in position and its apertures 44 are available for wire to be strung so as to increase the height of the fence.

It follows from the foregoing that the smaller size coupling tube 10 is available to couple two conventional star pickets 40 together in co-axial configuration so as to effectively provide a head high, or higher, fence post. Typically, such a coaxially joined fence post can be 1.2 m +1.8 m equals 3 m in total above the ground. Alternatively, the added fence post can be shorter than the conventional 1.8 m post. For example, if a shorter post of 1.35 m is used then the height of the heightened fence is 1.2 m + 1.35m equals 2.55 m. In particular, such heightened fences will be effective in preventing kangaroos and deer from jumping over the fence.

Fig. 11 illustrates an alternative arrangement for coaxially connecting two conventional star pickets 40. In this arrangement, the lower star picket 40 is in the fence as before and is effectively unchanged. The coupling tube 10 is slid into position as before, however, the upper conventional star picket 40 is inverted before being slid into the coupling tube 10. This has the consequence that the “upper” end of each of the star pickets 40 are adjacent each other. This has the advantage that a tie wire 55 can be passed through the two “uppermost” apertures 44 of the adjacent posts 40 thereby tying the two posts 40 together. This resists upward movement of the upper post 40 as, for example, happens when the coaxially aligned posts are located in a dip or other undulation in the ground surface and the tension in the fencing wires tends to pull the upper post 40 upwardly. In this configuration, the aperture 47 adjacent the point 48 of the upper post 40 is available for a top wire to be strung on the fence.

Preferably, in accordance with a further embodiment of the present invention, the normally ground engaging tip 48 of the post 140 is provided with a small circular aperture 147 of the same size as the conventional apertures 44 of the conventional post 40. This is very counter-intuitive because such an aperture 147 in a conventional post 40 would be buried under the soil and would have no role to play in the fence. Indeed, if the post 140 of Fig. 28 is used as the ground engaging (or lower) post of the fence, then the aperture 147 has no role to play. However, where the post 140 is used as the upper post of the fence, then the aperture 147 can be used to support the uppermost wire of the fence. This will normally be “head high” or higher.

Turning now to Figs. 12-15, a conventional T-post 61 as used in the USA is illustrated. The post has a stem 62 and a crossbar 63. The T-post 61 has no apertures but instead has a series of bumps or protrusions 64 on the surface of the crossbar 63 facing away from the stem 62. A spade (not illustrated but conventional) is sometimes included on the T-post 61. A coupling tube 200 can be dimensioned to fit the T-post 61 as illustrated in Figs. 13 - 15. This enables the coupling tube 200 to be slid onto the upper end of one T-post 61, and the lower end of another T-post 61 to be slid into the upper end of the coupling 200 to complete the coaxial installation as illustrated in Fig. 13.

A particular advantage of the coupling tube 200 as seen in Fig. 15 is that whereas the coupling tube of the above-mentioned US Patent No 5, 395, 093 covers up the protrusions 64 adjacent the join between the two post 61, the coupling tube 200 of this embodiment enables the heads of spaced apart TEK screws 28 to substitute for the covered protrusions 62. Thus wires 66 can be held in place by corresponding tie wires 67 so as to hold each wire between either a pair of screws 28 or one screw 28 and the nearest adjacent protrusion 64. In addition, the TEK screws 28 stop the coupling tube 200 sliding down the post. Furthermore, most of the variation in the T-posts available on the US market is concentrated in the horizontal extent, or width, of the stem 62, whereas the width of the crossbar 63 is, by comparison, relatively constant. A particular advantage of the tube 200 is that its open mouthed slot 13 receives the stem 62 and can thus accommodate essentially any variation in the width of the stem 62. That is, the tube 200 is, by design, adapted to accommodate a wide range of the T-posts available on the US market.

Turning now to Figs. 16-19, the situation occurring most often in Australia is that the existing fence which is to have its height raised, is formed using conventional star pickets 40. As a consequence, a conventional star picket 40 (possibly of shorter length than is conventional and therefore less expensive) is located above the existing star picket 40, as illustrated in Figs. 10 and 11. However, there are a number of fences which are formed from the BEEFY style star pickets 41 and which the fence owner wishes to raise in height. Since the BEEFY style star picket 41 is considerably more expensive than the conventional star picket 40, it is not an economic proposition to locate one BEEFY style star picket 41 above another BEEFY style star picket 41. In general, domestic stock cannot reach the upper fence post, with the result that it is subjected to relatively little strain in normal use. Therefore, it is economically desirable that where the lower posts are the BEEFY star pickets 41, then the upper posts should be the less expensive conventional star pickets 40.

As illustrated in Figs. 16-19, this is achieved by sliding the lower end 51 of a coupling tube 100 onto the uppermost end of the existing, ground engaging BEEFY star picket 41, and then sliding a conventional star picket 40 into the upper end 52 of a slimmer coupling tube 10. Then the lower end 51 of the of the slimmer coupling tube 10 is slid into the upper end 52 of the larger coupling tube 100.

As seen in Fig. 17, the coupling tube 10 is dimensioned to fit within the interior 19 of the coupling tube 100. If desired, a TEK screw 28 can be passed through the back portion 14 of each of the coupling tubes 10, 100 to permanently interconnect the two tubes. If required, a tie wire 55 (as seen in Fig. 11) can be placed through the “uppermost” aperture 44 of each of the posts 40, 41 so as to tie the conventional star picket 40 to the BEEFY star picket 41 and thereby prevent the conventional star picket 40 from moving upwardly relative to the star picket 41. For example, this may be required in undulating ground where the star pickets are located in a dip and therefore the wire tension urges the fence posts upwardly. It is also possible to use TEK screws 28 with a longer shank so as to drive the tip of one or more TEK screws 28 into frictional engagement with the star picket 40 or 41, or both. This enables the tubes 10 and 100 to be clamped or fixed to the pickets 40,41.

Turning now to Fig. 20, a coupling tube 10 can surprisingly be dimensioned to receive either a conventional Y-shaped star picket post 40 of Australia, or a conventional T- shaped post 61 of America. The post 40 is illustrated in dot-dash lines in Fig. 20 and the post 61 is illustrated in dashed lines in Fig. 20. It will be seen that the bumps or protrusions 64 of the T-post 61 are accommodated in the interior 19 of the coupling tube 10. A significant advantage of this arrangement is that the same rolling equipment can be used to produce products for two significant but different markets.

Turning now to Figs. 21-29, the dropper 410 of the preferred embodiment takes the form of a steel strip which is rolled into a sleeve having a lozenge like configuration when viewed in cross-section. The tube has a longitudinal axis 411 and a longitudinally extending open mouthed slot 413 so that the transverse cross-sectional configuration resembles the letter C.

The tube 410 has a back portion 414 which has two flanks 415, 416 between which there is a shallow V-shaped bend 17 of approximately 120° and preferably lying within the range of 110-150°. Extending away from the bend 417, the flanks 415, 416 respectively terminate two corresponding acute V-shaped elbows 421, 422, each of which has a corresponding free arm 424, 425. The V shaped elbows 421,422 have a bend of approximately 60° and preferably lying within the range of 50-80°. The free arms 424, 425 each terminate in a corresponding edge of the slot 413.

As illustrated, the dropper 410 is of indefinite length. The dropper 410 is preferably rolled from sheet steel such as galvanised high tensile sheet steel which is approximately 1.6 mm in thickness. Since the length of the dropper depends upon the height of the fence, the dropper 410 can be manufactured in different sizes, typically ranging from 900mm to 2.8 m. Preferably the dropper 410 is rolled using the same rolls as are used to roll the post coupling tube 10 of Figs. 1-20.

It has been found that the configuration inherent in the dropper 10 is very strong and is therefore much stronger than conventional droppers used hitherto. Normally a series of holes (not illustrated but conventional) are punched into the sheet steel used to form the dropper 410 prior to the dropper 410 being rolled. These holes can receive wires directly or can be used to locate a clip which maintains the wire in relation to the hole.

Turning now to Fig. 28, a post 140 of Y-shaped configuration and indefinite length is illustrated having the tip aperture 147 as described above. The other apertures 44 can either be of conventional configuration and spacing, or can be of a different configuration and spacing, if desired. Also, the length of the post 140 can be selected as desired to co-operate with the height of the existing ground engaging posts, so as to determine the height of the extended fence posts, and thus the height of the extended fence.

As seen in Fig. 29, in a still further embodiment a sleeve 300, of suitable dimensions and configuration, can be provided with a pair of opposite apertures 327 (only one of which is visible in Fig. 29). Each of the apertures 327 is located in a corresponding one of the elbows 21, 22 and is thus able to receive a pan headed metal thread bolt 328 which has a shank length which enables it to extend right across the sleeve 300 and engage with a nut 329. Tightening the nut 329 onto the bolt 328 draws the elbows 21, 22 together, and thus clamps both posts such as 40, 41, 140. The position of the apertures 327 and bolt 328 is preferably midway along the sleeve 300 so that the bolt 328 sits between the pair of posts.

Alternatively, the bolt 328 and nut 329 can be replaced by a self-tapping fastener 330 with metal cutting threads and having a shank long enough to extend between and into both apertures 327. Thus, the fastener 330 can also be used to draw the two elbows 21, 22 together and thereby clamp the posts. It will be seen from the foregoing that the coaxial mounting of two fence posts 40, 41, 61, 140 is able to be easily achieved utilising the coupling tube 10, 100, 200, 300 of the described embodiments.

A further advantage of the present invention is that the coupling tubes 10, 100, 200, 300 are small and relatively lightweight, especially if rolled from high tensile steel. Thus, they are easily sold via mail order to remote farmers who already have an existing stock of posts 40, 41, 61, 140 or to whom a local produce supplier is nearby, the local supplier having an existing stock of posts 40, 41, 61, 140.

In addition, the arrangement lends itself to firstly low-cost manufacture and, secondly, in the event that small variations in posts are encountered, it is then possible for the manufactured tube to be either crimped or pressed slightly or expanded slightly so as to adjust to the exact size of the farmer’s posts. This size adjustment is able to be carried out either by the sleeve manufacturer or by the farmer or other end user.

As seen in Figs. 30-32, an internal strut 501 can be used to support a length of fence post or dropper 10, 200, 300, 410 etc. in a cantilever fashion and at an inclined angle, above a generally vertical length of fence post or dropper 10, 200, 300, 410 etc. In this way the top of a fence incorporating the vertical length of fence post or dropper can be provided with an upper portion which deters climbing animals such as cats, foxes and the like.

The internal strut 501 is formed from a strip of sheet steel 502 which is preferably deformed by two bending actions so as to create a first bend about the longitudinal axis of the strip 502 having a generally C-shaped configuration and also a second transverse V-shaped bend. The interconnection between the fence post or dropper and the internal strut 501 can be a friction fit. Alternatively, or in addition, a fastener such as TEK screw 28 (Fig. 17) but with a longer shank can be driven into and through the fence post or dropper in the direction of arrow A so that the tip of the shank bears against the internal strut 501. In this way the fence post or dropper and the internal strut 501 are effectively releasably clamped together. In some instances, an exclusion fence requires two oppositely directed cantilever arms and this can be accommodated with the Y-shaped internal strut 505 as illustrated in Figures. 33-35. The strut 505 preferably is formed from an internal strut 501 onto which is welded a base stem 506. As seen in Fig. 33, the base stem 506 is accommodated within the vertical fence post or dropper 10, 200, 300, 410 etc. which in this instance has its lower end engaged with a star picket 31. Each arm of the V - shaped portion 501 receives a corresponding length of fence post or dropper 10, 200, 300, 410 etc. Again, the interconnection between these portions can be by means of a friction fit and/or a TEK screw or similar fastener.

A more versatile form of Y -shaped strut 510 is illustrated in Figures. 36-40. Here the V-shaped portion 511 is essentially the same as the internal strut 501, save that it is provided with a centrally located aperture 513 by means of which it can be bolted to an upright joiner 515. As seen in Figs 37-40, the upright joiner 515 is fabricated from the same strip steel 502 as the internal strut 501 but only provided with the first longitudinal bend to create the C -shaped configuration. It is docked to length and provided with a concave arcuate upper end 517 and a convex arcuate lower end 518. The shape of these ends conforms with the nature of the first bend of the V shaped portion 511.

In addition, the upright joiner 515 is provided with two threaded protrusions 527 and 528 which extend from the upper end 517 and the lower end 518 respectively. These threaded protrusions 527 and 528 are welded to the upright joiner 515. If desired, the threaded protrusions 527 and 528 can be provided by a single length of threaded rod rather than two lengths as illustrated.

As seen in Fig. 39, a nut 520 enables the V shaped portion 511 to be connected to the lower end 518 of the upright joiner 515 in an upright V-configuration. Alternatively, as illustrated in Fig. 40, the V shaped portion 511 can be connected to the upper end 517 of the upright joiner 515 in an inverted V-configuration. In this way the corresponding cantilever arms (not illustrated in Figs. 36-40) can be made to either point up or point down respectively. An important advantage of this embodiment is that the purchaser can experiment as to whether the cantilever arms of his fence should point up or point down and adjust them accordingly without the need to specify which one is required in the initial purchase. Preferably, the aperture 513 is formed with two oppositely facing extensions as illustrated in Fig. 36. These extensions enable rainwater to drain away and thereby protects the arrangement from rust.

Turning now to Figs. 41-44, a strut arrangement of another embodiment is illustrated. The cantilever strut 811 is of the same general form as the V-shaped portion 511 and is provided with guide holes 812 which receive tech screws 813 as illustrated in Figs. 43 and 44. The vertical strut 815 is longitudinally split at its upper end so as to form two tabs 816 and 817 which are bent at an angle so as to mate with the surfaces of the cantilever strut 811. This enables the cantilever strut 811 and the vertical strut 815 to be inter-engaged and secured to each other as illustrated in Figs. 43 and 44. Since the cantilever strut 811 is intended to be installed facing upwardly, it is preferably provided with a central hole to permit drainage.

Whilst the strut arrangement of Figs. 41-44 permits two cantilever arms to be installed in a Y-shaped configuration, as illustrated in Figs. 45-47, it is also possible for two cantilever arms to be installed in a droopy T configuration as indicated in Fig. 47.

Here the cantilever strut 811 is essentially as illustrated in Figs. 41-44, however, the vertical strut 915 and its two tabs 916 and 917 are bent differently so as to accommodate the different surfaces of the cantilever strut 811 with which the tabs engage. Again, two TEK screws 813 are used to hold the struts and tabs in an engaged configuration.

At each end of a fence is a strainer post, end assembly, or similar which resists the tension in the strained wire of the fence. Where a new exclusion fence is erected, it is necessary to erect high and structurally strong strainer posts or end assemblies. These can be difficult and expensive to erect. Figs. 48 - 50 illustrate how a conventional waist high strainer post 700 having an inclined brace 701 can be modified using a conventional heavy duty star picket 703, such as those sold in Australia under the registered trade marks BEEFY and MaxY. This permits the wires 631, 632, 633 of the upper fence portion 624 of Fig. 50 to be strained.

As seen in Fig. 48, two short lengths of the larger size coupling tube 100 as illustrated in Figs. 17-19 are attached to the strainer post 700 with each having a single selftapping TEK screw 704 in order to make the necessary connection. The positions of the two TEK screws 704 defines a straight line interconnecting the screws and each of the coupling tubes 100 is able to pivot slightly about its screw 704. As a consequence, the heavy duty star picket 703 can be slid into the coupling tubes 100 as illustrated in Fig. 49. During the sliding action, the coupling tubes 100 pivot slightly so as to become exactly aligned with the longitudinal axis of the heavy duty star picket 703.

It is not necessary to drive the heavy duty star picket 703 into the ground. It is sufficient merely to hold the star picket 703 relative to the coupling tubes 100. This can be done with a further TEK screw 705 which, as illustrated in Fig. 50, is passed through the lower coupling tube 100 and into the lower end of the heavy duty star picket 703. This is enough to stop the heavy duty star picket 703 moving upwardly relative to the coupling tubes 100.

Thereafter, the upper wires 631, 632, 633 can be tied to the upper end of the heavy duty star picket 703 and strained to the desired tension as illustrated in Fig. 50.

A similar construction can be used for timber end assemblies, metal strainer posts, and the like, again using a pair of aligned coupling tubes 100.

As seen in Figs. 51 -57, an agricultural fence clip 610 of a first embodiment is illustrated. The clip 610 has a single central loop 11 from which extend in opposite directions two arms 613, 614. As best seen in Figs. 56 and 57, the arms 613, 614 are substantially co-planar. As best seen in Figs. 53 and 54 when looking in the direction of the longitudinal axis of the central loop 11, the central loop 11 appears at the apex of a V formed by the arm 613, 614. Each of the arms 613, 614 terminates in a reentrant hook 615, 616 each of which is preferably formed by bending the high tensile wire from which the clip 610 is fabricated through an angle of approximately 120° of a partial circle having a diameter of approximately 7 mm.

The central loop 611 in this embodiment does not form an entire turn of 360°, however, the nearly entire turn is sufficient to form a tension spring 612 so that the hooks 615, 616 can be moved towards and away from each other thereby resiliently deforming the loop 611.

Turning now to Figs. 58 and 59, a single conventional star picket 40 of a substantially conventional agricultural fence 621 is illustrated. The fence 621 consists of a conventional waist high lower fence portion 23 to which has been added an upper, head high, fence portion 624. The lower fence portion 623 is topped by a barbed wire 627 which sits above a plain wire 628, and a prefabricated wire mesh 629 such as that sold under the trade name HINGELOCK, or similar.

The fence 21 is extended by use of a fence post extender 410 such as that illustrated in Fig. 21. The fence post extender 410 of the preferred embodiment takes the form of a steel strip which is rolled into a sleeve having a lozenge like configuration when viewed in cross-section. The tube has a longitudinal axis 411 and a longitudinally extending open mouthed slot 413 so that the transverse cross-sectional configuration resembles the letter C.

The tube 410 has a back portion 414 which has two flanks 415, 416 between which there is a shallow V-shaped bend 417 of approximately 120° and preferably lying within the range of 110-150°. Extending away from the bend 417, the flanks 415, 416 respectively terminate two corresponding acute V-shaped elbows 421, 422, each of which has a corresponding free arm 424, 425. The V shaped elbows 421,422 have a bend of approximately 60° and preferably lying within the range of 50-80°. The free arms 424, 425 each terminate in a corresponding edge of the slot 413.

The fence post extender 410 can be of any one of various lengths, such as 300, 600 900, and 1200 mm. The fence post extender 410 is preferably rolled from sheet steel such as galvanised high tensile sheet steel which is approximately 1.6 mm in thickness.

It has been found that the configuration inherent in the fence post extender 410 is very strong. Normally a series of holes (such as the holes in Fig. 29 or the holes 427 in Figs. 58 and 59) are punched into the sheet steel used to form the fence post extender 410 prior to the fence post extender 410 being rolled. These holes 427 can be used to locate the clip 610 which maintains the corresponding wire in relation to the hole 427.

As seen in Figs. 58 and 59, one hook 615 of the clip 610 is pushed into one hole 427 and the other hook 616 is able to be pushed into an adjacent hole 427. This pushing action spreads the arm 613, 614 apart and enables the hooks 615, 616 to enter their corresponding holes 427. The arm 613, 614 then spring back into their rest position, thereby entrapping the re-entrance hooks 615, 616 within the interior of the fence post extender 410. This is schematically illustrated in Fig. 59.

With the clips 610 held in position, upper wires 631, 632 and 633 can be threaded through the loops 611 of the corresponding clips 610. More than three, or less than three, upper wires can be used as dictated by the design of the upper fence portion 624.

As seen in Figs. 60 and 61, in an alternative arrangement, the clips 610 can be attached to the upper wires 631, 632 and 633 after the upper wires have been strained. As illustrated in Figs. 60 and 61, the wires once strained extend horizontally in a taut condition, only one of the wires being illustrated in broken lines in these two drawings. Each of the clips 610 can have its loop 611 grasped by two fingers of the fencer (not illustrated). Then the clip 610 is pushed onto the wire with one of the arms 613, 614 passing on one side of the wire and the other of the arms passing on the other side of the wire. Simultaneously, the clip 610 is pushed beyond the wire and rotated in a clockwise direction as seen in Fig. 60, so as to arrive at the situation as illustrated in Fig. 61. With the fencer still grasping clip 610, the hooks 615, 616 can then be pushed into the desired corresponding pair of holes 427 of the fence post extender 410. Turning now to Fig. 62, a clip 636 of a second embodiment is illustrated which differs from the clip 610 of the first embodiment only in that the torsion spring 612 is formed, not from a single loop 611, but from a double loop 638. The foregoing describes only some embodiments 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.

The term “comprising” (and its grammatical variations) as used herein is used in the inclusive sense of “including” or “having” and not in the exclusive sense of “consisting only of’.