Field of the Invention

[001 ] The present invention relates to a barrier to be used for preventing access to an area by sharks.

Background to the Invention

[002] Protection against shark attack is becoming an increasingly important issue, with the number of attacks in some locations increasing in recent times. Various methods and devices have been proposed to reduce the risk of shark attacks. Shark nets have been used for many years to reduce the chances of sharks entering areas where people are swimming by creating a physical barrier.

[003] The present invention relates to a barrier for preventing access by sharks having an improved construction to allow effective operation of the barrier in a cost effective and easy to install manner.

Summary of the Invention

[004] According to one aspect of the present invention there is provided a barrier comprising:

a plurality of parallel horizontal cables; and

a plurality of brace members each comprising an elongate member having a first connector on a first end and a pair of second connectors on a second end;

wherein sets of brace members are provided separated at intervals along the width of the barrier such that the brace members of each set extend along a vertical axis from a lowermost horizontal cable to an uppermost horizontal cable with each of the brace members extending between a pair of adjacent horizontal cables such that a first of the pair of horizontal cables is received in the first connector and a second of the pair of horizontal cables is received in the second connectors, wherein the first connector of each of the brace members is received between second connectors of an adjacent brace member.

[005] Preferably each of the first and second connectors comprises a channel member defining an opening into which is received one of the horizontal cables.

[006] Preferably the channel members are C-shaped in a cross-section taken parallel to a longitudinal axis of the elongate member such that the channel members define a cylindrical chamber for receiving a portion of one of the cables by inserting the horizontal cables through the opening.

[007] Preferably longitudinal axes of the cylindrical chambers of the channel members are oriented perpendicularly to the longitudinal axis of the elongate member.

[008] Preferably the openings of the first and second connectors are oriented in the same direction towards a first side of the elongate member.

[009] In a preferred embodiment, the second end of the elongate member is provided with a cross member and the second connectors are provided adjacent opposed ends of the cross member such that the longitudinal axes of the cylindrical chambers are coaxial and a gap is defined between the second connectors.

[010] Preferably the first connector of each brace member engages with a horizontal cable within the gap of an adjacent brace member.

[01 1 ] In a preferred embodiment, the channel members of the first and second connectors are provided with protrusions on inner surfaces thereof to engage into the horizontal cables to restrict movement of the horizontal cables relative to the first and second connectors. [012] Preferably outer surfaces of the channel members of the first and second connectors are provided with a groove and an aperture is provided on a side of the channel member adjacent the elongate member such that cable ties may be passed through the apertures and located in the grooves around the periphery of the channel members to extend across the opening to retain the horizontal cables.

[013] Preferably flotation devices are secured along the length of the uppermost horizontal cable.

[014] In a preferred embodiment, ends of the horizontal cables are secured to pylons by springs which expand and contract to allow vertical changes in the position of the barrier due to tidal and wave movement.

[015] Preferably each of the springs extends between a loop formed on the end of the horizontal cable and an anchor provided on a vertical side the pylon.

[016] In one embodiment, the elongate members are provided with a flexible joint located adjacent a centre of the elongate member to allow the first end of the elongate member to bend relative to the second end thereof.

[017] In one embodiment, vertical cables are provided extending between the lowermost horizontal cable and the uppermost horizontal cable adjacent to one of the sets of brace members, the vertical cable being secured to the brace members of the set by one or more couplers.

[018] In a preferred embodiment, each of the couplers comprises a flexible spiral band wrapped around the vertical cable and a portion of the length of the elongate member.

Brief Description of the Drawings

[019] The invention will now be described, by way of example, with reference to the following drawings, in which: [020] Figure 1 is a view of a portion of a barrier in accordance with the present invention;

[021 ] Figure 2 is a close up view of a portion of the barrier of Figure 1 ;

[022] Figure 3 is an exploded view of the portion of the barrier of Figure 2;

[023] Figure 4a is an upper perspective view of a brace member of the barrier of Figure 1 ;

[024] Figure 4b is a side view of the brace member of Figure 4a;

[025] Figure 5 is a side view of the brace member in a flexed state;

[026] Figure 6a is an upper perspective view of a second embodiment of a brace member in accordance with the present invention; and

[027] Figure 6b is a side view of the brace member of Figure 6a;

[028] Figure 7a is a front view of a second embodiment of a barrier in accordance with the present invention;

[029] Figure 7b is a close up view of an upper portion of the barrier of Figure 7a;

[030] Figure 8a is a front view of the barrier of Figure 7;

[031 ] Figure 8b is a close up view of a lower portion of the barrier of Figure

8a; and

[032] Figure 9 is a view of one of the brace members of the barrier of Figure 7.

Detailed Description of Preferred Embodiments

[033] Referring to the Figures, there is shown a barrier 10 comprising generally a plurality of horizontal cables 12 and a plurality of brace members 14.

[034] In the embodiment shown, the barrier 10 includes pylons 16 between which the horizontal cables 12 extend. The pylons 16 comprise vertical posts secured in the seabed around the perimeter of an area which is to be enclosed by the barrier 10. The cables 12 each extend between a pair of adjacent pylons 16. The cables 12 are parallel to each other and are secured to the pylons 16 at regular intervals. The cables 12 therefore form the horizontal members of a mesh structure to be formed by the barrier 10. [035] The brace members 14 each comprise an elongate member 18. Each elongate member 18 is to extend vertically between an adjacent pair of the cables 12. The brace members 14 engage with a first of the pair of adjacent cables 12 at a first end and a second of the pair of adjacent cables 12 at a second end. The brace members 14 are provided in sets where each brace member 14 in the set extends along a common vertical axis between the lowermost cable 12 and the uppermost cable 12. The sets of brace members 14 are separated horizontally at intervals along the length of the cables 12 such that the brace members 14 secure the cables 12 relative to each other.

[036] The brace members 14 includes a first connector 20 at a first end of the elongate member 18. The brace members 14 also include a pair of second connectors 22 located at the second end of the elongate member 18. Each of the first and second connectors 20 and 22 comprises a channel member 24 defining an opening 26.

[037] In the embodiment shown, the channel members 24 are generally C- shaped in a cross-section taken parallel to a longitudinal axis of the elongate member 18. The channel members 24 therefore define a generally cylindrical chamber for receiving a portion of one of the cables 12 by inserting the cables 12 through the opening 26. Longitudinal axes of the cylindrical chambers of the channel members 24 of the first and second connectors 20 and 22 are oriented perpendicularly to the longitudinal axis of the elongate member 18. The openings 26 of the first and second connectors 20 and 22 are oriented in the same direction towards a first side of the elongate member 18.

[038] The first connector 20 is preferably integrally formed with the elongate member 18 on a first end thereof. The second connectors 22 are preferably integrally formed with the elongate member 18 on the second end thereof. The second end of the elongate member 18 is provided with a cross member 28 on which is provided the second connectors 22. The second connectors 22 are provided adjacent opposed ends of the cross member 28 such that the longitudinal axes of the cylindrical chambers are coaxial. The second connectors 22 are separated such that a gap 34 is defined between the second connectors 22. [039] The channel members 24 of the first and second connectors 20 and 22 are provided with protrusions 30 on inner surfaces thereof. The protrusions 30 in the embodiment shown comprise spikes provided to engage into the cables 12 to restrict movement of the cables 12 relative to the first and second connectors 20 and 22.

[040] The outer surfaces of the channel members 24 of the first and second connectors 20 and 22 are provided with a groove 32 therein. An aperture 36 is provided between the channel member 24 of the first connector 20 and the end of the elongate member 18. Apertures 36 are also provided between the channel members 24 of the second connectors 20 and the cross member 28.

[041 ] Cable ties 38 are provided to secure the cables 12 within the channel members 24 of the first and second connectors 20 and 22. The cable ties 38 are passed through the apertures 36 and are located in the grooves 32 around the periphery of the channel members 24. Ends of the cable ties 36 may be engaged to extend across the openings 26 of the channel members 24 such that the cables 12 are retained within the channel members 24.

[042] As can be seen in Figure 1 , the brace members 14 are provided at regular intervals along the lengths of the cables 12. Each brace member 14 is secured to extend vertically between an adjacent pair of the cables 12. Adjacent pairs of cables 12 are secured by further brace members 14 wherein the first connector 20 of each of the further brace members 14 is engaged with the cable 12 in the gap 34 defined between the second connectors 22. A set of brace members 14 are therefore connected vertically extending from a lowermost cable 12 to an uppermost cable 12. The brace members 14 and the cables 12 therefore define a mesh structure formed as a generally rectangular array.

[043] The barrier 10 is provided also with flotation devices 40. A plurality of flotation devices 40 are secured along the length of the uppermost cable 12. The flotation devices 40 in use float on the surface of the ocean and thereby retain the mesh structure formed by the cables 12 and the brace members 14 in a vertical plane extending downwardly from the surface. [044] Ends of the cables 12 are secured to the pylons 16 by springs 42. Each of the springs 42 extends between a loop formed on the end of the cable 12 and an anchor 44 provided on a vertical side the pylon 16. The springs 42 are provided to supply tension to the cables 12 to keep the barrier 10 in position. The springs 42 may also expand and contract to allow vertical changes in the position of the barrier 10 due to tidal and wave movement.

[045] In the embodiment of Figures 1 to 5, the elongate members 18 are provided with a flexible joint 46 located adjacent a centre of the elongate member 18. The elongate members 18 of the embodiment of Figures 1 to 5 are expected to be formed of a suitable plastic material and the flexible joint 46 comprises a corrugated structure provided to allow a first end of the elongate member to bend relative to the second end thereof (as can be seen in Figure 5). The flexible joint 46 therefore allows some movement of the cables 12 relative to each other to further accommodate for movement of the barrier 10 caused by changing ocean conditions.

[046] Figure 6 shows a further embodiment of a brace member 14 in accordance with the present invention. The brace member 14 is of a similar construction to the previous embodiment however does not include the flexible joint 46.

[047] Figures 7 to 9 show a second embodiment of a barrier 10 in accordance with the present invention. The barrier 10 of Figures 7 to 9 is similar to the embodiment of Figures 1 to 6 and like reference numerals are used to denote like parts.

[048] The barrier 10 includes vertical cables 13 provided for additional strengthening of the barrier 10. The vertical cables 13 extend between the lowermost cable 12 and the uppermost cable 12 adjacent to one of the sets of brace members 14. The vertical cable is secured at a lower end thereof to a base chain 50 by appropriate means. The base chain 50 extends along the lower side of the barrier 10 and provides additional weight to hold down the barrier 10. [049] The vertical cable 13 is secured to the brace members 14 of the set by a plurality of couplers 52. Each of the couplers 52 comprises a spiral band 54. The spiral band 54 is flexible and wrapped around the vertical cable 13 and a portion of the length of the elongate member 18 (as can be seen in Figure 9), thereby holding the vertical cable 13 in place.

[050] It will be readily apparent to persons skilled in the relevant arts that various modifications and improvements may be made to the foregoing embodiments, in addition to those already described, without departing from the basic inventive concepts of the present invention For example, while the barrier 10 in the embodiment shown extends between pylons 16, the barrier 10 may be used without pylons 16. The barrier 10 may be secured in place through other means, such as by securing the base chain 50 in place relative to the sea bed.