GB2322386A

GB2322386A - Fencing nets with varying strength

Info

Publication number: GB2322386A
Application number: GB9703729A
Authority: GB
Inventors: Mr William Mathew Doncaster; Mr Mark Richardson
Original assignee: TORNADO WIRE Ltd
Current assignee: TORNADO WIRE Ltd
Priority date: 1997-02-22
Filing date: 1997-02-22
Publication date: 1998-08-26
Also published as: GB9703729D0

Abstract

A fencing net which has full strength e.g. at shoulder height of animals but which is made less strong elsewhere to save weight is formed from interconnected horizontal wires (1) and vertical wires (4,4B) with some of the vertical wires (4B) spanning only the region where full strength is required. The net is made on a loom in which a feed roller for the vertical wire is lifted intermittently, e,.g. by an eccentric under pneumatic control, to interrupt the feed.

Description

IMPROVEMENTS INlOR RELATING TO FENCING NETS This specification relates to wire fencing commonly referred to as 'nets' or mesh fencing, in which the line and stay wires are arranged essentially at right angles to each other. It does not relate to 'chain link' types of fencing.

Fencing nets consist of horizontal line wires with vertical stay wires extending between the topmost and bottom-most line wires. The stay wires are fixed to the line wires at every connection and the ends of the stay wires are fast with the topmost and bottommost line wires respectively. Conventional nets are produced in a rectangular pattern with every stay wire nominally identical to those on either side. There are occasions when this makes the net much heavier than it need be as different mechanical strengths may be required from different parts of the net. For example, animals tend to push the fencing at around shoulder height and this is where the strength must be greatest. Deer fencing has to be strong enough to withstand the pushing of a large stag at shoulder height, yet high enough to deter the animal fran attempting to jump over. Clearly the maximum strength required at shoulder height is not needed near the top of the fence where visual determine is the sole requirement Thus a conventional net with equal strength throughout the whole of its height is much heavier and uses additional wire than one especially designed with different strength zones.

There is thus a need to be able to design the stay wire arrangements in order to give fencing nets their full strength in the particular areas where this is required and to be able to save weight where lower strength is permissible.

According to a first aspect of the invention there is provided a fencing net comprising: a a plurality of line wires including a top line wire and a bottom line wire; ii first stay wires extending in an essentially continuous line from said top line wire to said bottom line wire; iii second stay wires differing from said first stay wires in that at least one interrupt between a pair of adjacent line wires is provided; and iv means to secure said line wires and said stay wires to each other at every intersection; characterised in that said first and second stay wires are arranged in a pre-determined pattern.

According to a first variation of the first aspect of the invention, said second stay wires may be interrupted between every pair of adjacent line wires.

According to a second variation of the first aspect of the invention, third stay wires are provided with a different pattern of interrupt(s) to said second stay wires and said first, second and third stay wires are arranged in a predetennined pattern.

in a preferred embodiment, the first stay wires extend in an essentially continuous line from the top to the bottom of the fencing net and the second stay wires are provided with a number of interrupts, for example in the upper and lower zones of the net, where the mechanical strength required is not so great. The arrangement of said first and second stay wires may be alternate or, there may be two second stay wires adjacent to each other, to give what ever combination of mechanical properties and weight of fencing is required.

According to a second aspect of the invention, a fencing-making loom is provided including: i) a timing/positioning mechanism for identifying the position of the stay wires along the line wires; ii) an interrupt mechanism operable to restrict the feeding of the stay wire(s) at predetermined intervals; iii) a connection between said timing/positioning mechanism and said interrupt mechanism; iv) a means of communicating via said connection to cause said interrupt mechanism to becomeirot become operational in relation to the timing/positioning mechanism according to a preset pattern; and v) means to feed the stay wire(s) to the appropriate line wires, cut it/them to length and secure said stay wire(s) to said line wires.

According to a first variation of the second aspect of the invention the interrupt mechanism has a first mode of operation in which the stay wire is fed normally to the loom and a second mode of operation in which the stay wire feed is interrupted.

In a preferred embodiment, the stay wire is advanced between friction rollers which are geared to the timing mechanism of the loom. An interrupt connection is provided such that, at predetermined points in the net making cycle, an eccentric means rotates to lift one of the friction rollers out of intimate contact with the uncut stay wire so that the forward friction drive is disengaged. Thus, for this particular part of the loom cycle, that particular section of the stay wire will not be advanced and an 'interrupt' will occur in the otherwise essentially continuous stay wire.

According to a second variation of the second aspect of the invention the means of interrupting the feeding of the stay wire has three modes of operation such that in said first mode of operation, the stay wire is fed normally to the loom, in the second mode of operation, the stay wire is fed with a first pattem of interrups and in the third mode of operation, the stay wire is fed with a second pattern of interrupts.

According to a third variation of the second aspect of the invention the means of interrupting the feeding of the stay wire is such that its three modes of operation may be engaged in any order according to a predetermined plan of settings in a preferred embodiment, the arrangement of the stay wires is such as to give wide freedorn to the mechanical designer as well as scope to improve the aesthetic qualities of the net, eg when it is viewed at an angle. For example, the stay wire pattern could be 12-3-2-1, where the numbers refer to the modes of feeder operation. This would allow the designer to achieve an optimum strength: weight ratio for any particular net requirement. Also the variation of the regularity of the net could make the fencing visually more attractive, especially when seen at an angle.

For a clearer understanding of the invention and to show how it may be carried into effect, reference will now be made, by way of example only, to the following figures in which: Figure 1 is a typical example of a normal fence net (prior art) Figure 2 is a typical example of a non-continuous stay wire stock fence.

Figure 3 is a typical example of a non continuous stay wire deer fence.

Figure 4 is a typical example of a net with some stay wires completely interrupted.

Figure 5 is a perspective view of a hinge joint Figure 6 is diagrammatic arrangement of one fonn of interrupt mechanism according to the invention.

In this description the same reference numeral is used for the same component or different components fulfilling identical functions.

Referring to Fig 1 the fencing net consists of continuous horizontal line wires 1. The top line wire is referenced 2 and the bottom line wire 3. Any number of line wires between the top and the bottom may be provided according to the requirement but for a deer fence up to about 19 line wires is the normal maximum. This could give a fencing net over 2m in height.

Figs 2 & 3 show examples of fencing nets where alternate stay wires do not extend the whole distance between the top 2 and bottom 3 line wires. The deer fence (Fig 3) has 3 distinct zones. The upper zone 5 is intended to deter the animal from attempting to jump the net and so does not require maximum strength The middle zone 6 is around shoulder height for typical deer and stay wires 4B are used to give the net its maximum strength in this critical zone. The lower zone 7 has the line wires 1 closer together to stop small animals squeezing through but stay wires 4B do not continue to the bottom wire 3 as this zone does not have to have the maximum strength of the middle zone. In Fig 2 stay wires 4A extend from the top wire 2 down to the next-to-the-bottom line wire. This design would be suitable for non-jumping animals, such as cattle or sheep.

Fig 4 shows an arrangement of the stay wires with every third one completely interrupted, ie as shown by the arrows 4C.

Fencing nets may be manufactured using two types of stay wire. In the first type, 'stiff' stay wires extend from the bottom wire 3 to the top wire 2 and the ends are wound around these two line wires. The connections between these stiff stay wires 4 and the line wires 1 are formed by separate short lengths of wire (not shown) wound round each intersection to form a knot. Alternatively, the connection between the line and stay wires may be formed by a welding process. The second type is the 'hinge' joint. Here short lengths of wire connect two adjacent line wires and the free ends are wound round the line wires to form the joint. This is shown in Fig 5 where the ends of two stay wires 4D and 4E are wound together round line wire 1, as shown. The apparatus hereinafter described refers to this second type of hinge joint, but the principle is equally applicable to both types of construction.

Referring to Fig 6, stay wire 4 is in the form of a continuous length of wire which is fed to the loom and cut to length according to the particular spacing between the two adjacent line wires 1 which it is to connect. The operation of the loom is that the line wires 1,2 & 3 are advanced by a distance equal to the spacing between adjacent stay wires 4 and stopped. The uncut stay wires are then fed forward, cut to length and wound round the appropriate pair of adjacent line wires, eg as shown in Fig 5. The stay wire 4 is advanced by friction between two rollers 8 and 9. A spring 27 urges roller 9 towards roller 8 so that the wire 4 is firmly gripped. Toothed drive wheels 10, 11 fast with rollers 8,9 respectively drive the two friction rollers 8,9 together and in opposite senses of rotation, as shown by the (unnumbered) direction arrows. For clarity, the connection between toothed drive wheels 10, 11 is not shown.

A drive shaft 14 from the loom mechanism drives toothed drive wheels 10, 11 via a toothed wheel 16 fast with shaft 14 and timing chains 13. An intermediate toothed wheel 17 is shown, but any appropriate connection may be used. Fast with shaft 14 is a cam 15. As shaft 14 rotates, cam 15 engages with piston 19A of pneumatic spool valve 19 causing air to flow along connections 18 to double acting cylinder 20 which drives a member 23 connected to eccentric lifter means 22. Lifter 22 rotates about axis 21 and causes lifter 24 to rise and fall lifting and lowering member 26 via hook 25 against the action of leaf spring 27. The action of lifting friction roller 9 against spring 27 removes the drive to wire 4 so that, when lifted, there is no drive to advance stay wire 4 even though rollers 8,9 continue to turn. As shaft 14 continues to rotate and piston 19A loses contact with cam 15, spring 27 urges friction roller 9 back into contact with wire 4 to advance it at the next stage of the cycle. The action of spring 27 resets members 24, 22, 23 and 20, thus maintaining piston 19A in contact with shaft 14.

Thus, as shaft 14 rotates, the wire 4 is firstly advanced when piston 19A is not bearing on cam 15 and secondly remains stationary when piston 19A is in contact with cam 15.

It will be noted that ller 9 bas to be lifted by only a very small amount, eg less tban lmm, for the forward friction drive to wire 4 to be completely disengaged.

In the example given, a pneumatic means is used to connect between a suitable drive shaft 14 on the loom (not shown) and the lifting means 21 - 26 but any equivalent mechanism may be used instead For example, the mechanism could be a mechanical timing chain, other mechanical connection or an electrical signalling means.

The mechanism shown is replicated for each stay wire section between every two adjacent pairs of line wires. The arrangement of cam 15 and the operation of eccentric lifter 22 is such that it/they may be provided with more than two positions so that different patterns of interrupt may be provided for adjacent stay wires. This allows stay wires with several interrupt patterns to be programmed into the loom so that a fence which is aesthetically pleasing may be constructeO In an alternative arrangement, eccentric lifter 22 may be replaced with a shaft(s) having one, or more, cams, ie similar to items 14 and 15. This shaft could be rotated to any one of a number of positions where the appropriate cam either would, or would not, engage with lifter 24.

The mechanism hereinbefore described is particularly suited to looms using the hinge joint type of construction. In this type of loom, the stay wire 4 is fed 8,9 along a tube (not shown) to the gap between two adjacent line wires 1. Thus, as an example, if there are 19 line wires on the loom, there will be 18 gaps and 18 separate stay wires are fed 8,9 along 18 tubes (not shown) to each of the gaps, cut to length and secured (Fig 5) to the adjacent pair of line wires 1. Hence the apparently continuous stay wire 4 (Fig 3) actually consists of 18 short lengths secured end-to-end. Thus, with 18 of lifters 24, any combination of stay wire interrupts can be preset from a continuous stay wire 4 to one completely interrupted 4C.

The same principle is applicable to looms using the stiff stay wire method of construction. For example, to make a stock fence (Fig 2), the stay wire guide tube (not shown) could terminate at top line wire 2 and would alternately feed full length stay wires 4 and shorter ones 4A. The interrupt mechanism would also disengage the means to secure stay wire 4A to bottom line wire 3, ie the knotting or welding process.

For the deer fence (Fig 3), the problem is slightly more complex as stay wire 4B must be advanced past zone S before securing to the line wires 1 in zone 6.

The use of the interrupt mechanism described hereinbefore enables a large loom to produce two (or more) small nets simultaneously. For example, if the loom has the capability for handling 19 line wires, a first ten line wire net may be set at points 1 to 10 and a second six line wire fence may be set at points 11 to 16. If the interrupt mechanism is arranged to be operational for all (ie first, second and third) stay wires between points 10 and 11, two separate fencing nets will be produced in the same production run.

In some areas, it is common practice to provide low fencing nets on the tops of dry stone walls to deter deer from jumping over. Using the principle just described, it is possible to construct six three-line wire nets simultaneously in one production run.

Where in the foregoing description reference has been made to elements or integers having known equivalents, then such equivalents are included as if they were individually set forth.

Although the invention has been described by way of example and with reference to particular embodiments, it is to be understood that modifications and/or improvements may be made without departing from the scope or spirit of the invention.

NOMENCLATURE 1 Line Wires 2 Top Line Wire 3 Bottom Line Wire 4 Continuous Stay Wire 4A Interrupted Stay Wire 4B Interrupted Stay Wire 4C Completely Interrupted Stay Wire 4D End of Hinge Joint Stay Wire 4E End of Hinge Joint Stay Wire 5 Upper Zone of Fence Net 6 Middle Zone of Fence Net 7 Bottom Zone of Fence Net 8 Friction Rollers 9 Friction Rollers 10 Toothed Drive Wheels 11 Toothed Drive Wheels 12 Leaf Spring 13 Timing Chain 14 Drive Shaft 15 Cam 16 Toothed Drive Shaft 17 Toothed Drive Shaft 18 Connection from Cam to Eccentric Lifter Shaft 19 Pneumatic Spool Valve 19A Piston 20 Double Acting Pneumatic Cylinder 21 Eccentric Lifter Shaft Axis 22 Eccentric Lifter Member 23 Member 24 Lifter 25 Hook 26 Member 27 Leaf Spring.

Claims

What we claim is:

I A fencing net comprising: i a plurality of line wires including a top line wire and a bottom line wire; ii first stay wires extending in an essentially continuous line from said top line wire to said bottom line wire; iii second stay wires differing from said first stay wires in that at least one interrupt between a pair of adjacent line wires is provided; and iv means to secure said line wires and said stay wires to each other at every intersection; characterised in that said first and second stay wires are arranged in a pre-determined pattern.
2 A fencing net, as claimed in claim 1 wherein said second stay wires are interrupted between every pair of adjacent line wires.
3 A fencing net, as claimed in claims 1 or 2, wherein third stay wires are provided with a different pattern of interrupt(s) to said second stay wires and said first, second and third stay wires are arranged in a predetermined pattern.
4 A fencing-making loom, for making the fencing nets claimed in claims 1 to 3, including: i) a timing/positioning mechanism for identifying the position of the stay wires along the line wires; ii) an interrupt mechanism operable to restrict the feeding of the stay wire(s) at predetermined intervals; iii) a connection between said timing/positioning mechanism and said interrupt mechanism; iv) a means of communicating via said connection to cause said interrupt mechanism to become/not become operational in relation to the timing/positioning mechanism according to a preset pattern; and v) means to feed the stay wire(s) to the appropriate line wires, cut it/them to length and secure said stay wire(s) to said line wires.
5 A fencing-making loom, as claimed in claim 4, wherein the interrupt mechanism has a first mode of operation in which the stay wire is fed normally to the loom and a second mode of operation in which the stay wire feed is interrupted.
6. A fencing-making loom, as claimed in claim 5, in which the stay wire feed drive mechanism incorporates a friction roller in firm contact with the stay wire.

7 A fencing-making loom, as claimed in claim 6, in which the stay wire feed drive is interrupted by moving the friction roller out of firm contact with the stay wire.

8 A fencing-making loom, as claimed in claims 5 and 6, wherein the fiiction roller is driven by a mechanical connection to a drive member in the loom.

9 A fencing-making loom, as claimed in claim 8, wherein the timing/positioning mechanism is provided operable by a mechanical connection to the drive member of the loom.

10 A fencing-making loom, as claimed in claim 8, wherein the timing/positioning mechanism is operable by a pneumatic connection to the drive member of the loom.

11 A fencing-making loom, as claimed in claims 9 and 10, wherein the timing/positioning mechanism is operable via an eccentric fast with the drive member of the loom.

12 A fencing-making loom, as claimed in claim 11 wherein the timing/positioning mechanism is operable according to a predetermined timing pattern determined by the size and positioning of the eccentric(s).

13 A fencing-making loom, as claimed in claim 12, wherein a spring is provided urging the friction roller into firm contact with the stay wire to move said stay wire forward in accordance with the operating cycle of the loom.

14 A fencing-making loom, as claimed in claim 13, wherein the interrupt mechanism operates by moving the friction roller out of firm contact with the stay wire against the pressure of the spring and maintains it out of firm contact for an appropriate part(s) of the operating cycle(s) of the loom.

15 A fencing-making loom, as claimed in claim 8, wherein the stay wire feed drive mechanism incorporates electrical or pneumatic components.

16 A fencing-making loom, as claimed in any preceding claim, wherein the timinglpositioning mechanism is operable by an electrical connection to the drive member of the loom.

17 A fence-making loom as claimed in claim 16, wherein the timing/positioning mechanism incorporates electrical or electronic components.

18 A fence-making loom and the products made by it as described in and by the above statement with reference to the attached drawings.