FLOATING SECURITY BARRIER

BACKGROUND OF THE INVENTION

[0001] This invention relates to a security barrier suitable for use in a water environment for example on a lake, in a river or at sea, or in an estuary and the like.

[0002] Some land and water-based installations are prone to attack by vandals, criminals, terrorists and other undesirable elements. For example oil installations in some countries can be attacked by insurgents or rebels. An oil plant or storage facility may be positioned on land close to water frontage. It is fairly easy to construct a security barrier on land to deter attackers. However an approach over water to a land or water-based installation is not that easily protected. Buoys and nets can be interconnected to provide a degree of protection but the buoys can be punctured and then sink. Another factor is that the movement of the water due to ebb and flow or tidal effects can be significant and this can lead to damage to the barrier components.

[0003] Economic considerations also come into play when erecting a barrier. A barrier should have a long life and provide a fair degree of protection, at a reasonable cost. The installation of a barrier, and the repair thereof when necessary, are also factors to be borne in mind.

[0004] In an attempt to meet the aforementioned requirements use has been made, in the past, of a barrier formed from a number of interconnected circular-cylindrical buoys In the applicant's opinion, these devices suffer from a number of drawbacks, namely: the buoys are expensive to fabricate; the buoys exhibit substantial resistance to water-

flow, or wave action, and the resulting forces can cause considerable wear, particularly due to relative movement between the buoys and supporting axles which pass through the buoys; opposing sides of adjacent cylinders are generally vertical and the gaps between adjacent buoys often constitute weak areas in a barrier; and the cylindrical buoys do not extend high above a water surface, or deep into the water, thus making it easier for an intruder to climb over, or to swim under, this type of buoy.

[0005] The invention is concerned with a security barrier which, at least partly, aims to address the aforementioned aspects.

SUMMARY OF THE INVENTION

[0006] The invention provides a buoy for use in a floating security barrier which includes a buoyant body, a plurality of deterrent components on an outer side of the body, a tie bar which extends through the body and fixing mechanisms at opposed ends of the tie bar which allow the body and the tie bar to rotate about an axis which is aligned with the tie bar relatively to the fixing mechanisms.

[0007] The body is preferably spherical, or substantially spherical, in shape.

[0008] Preferably the body includes a shell, for example of a suitable polymer material, which is filled with a settable foam e.g. marine foam.

[0009] A plurality of grooves may extend circumferentially around the body and the deterrent components may be positioned in the respective grooves.

[0010] The grooves may be spaced apart and parallel to one another.

[0011] Each deterrent component may be of any suitable kind but, preferably, comprises an elongate strip of material, for example of stainless steel, formed with a plurality of spikes, barbs or the like.

[0012] Each fixing mechanism may include an inner plate which abuts an inner surface of the shell, an outer plate which opposes the inner plate and which abuts an outer surface of the shell, a plurality of fasteners which secure the plates to each other with a portion of the shell sandwiched between the plates, and a swivel connector which is engaged with the outer plate.

[0013] The invention further extends to a floating security barrier which includes a plurality of buoys, each of the aforementioned kind, which are interconnected to each other in an array by engaging respective fixing mechanisms of adjacent buoys to each other.

[0014] Preferably the array is elongate, or substantially linear. However, to increase the effectiveness of the barrier, the array may be in any appropriate configuration.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The invention is further described by way of example with reference to the accompanying drawings in which :

Figure 1 is a plan view of an installation on land adjacent an estuary or river mouth which is protected using a floating security barrier according to the invention,

Figure 2 shows a buoyant body which is used in the security barrier,

Figure 3 is similar to Figure 2 but is partly sectioned to show an interior of the buoyant body,

Figure 4 illustrates a portion of the body in an exploded configuration and on an enlarged scale, Figure 5 shows how two of the buoys are interconnected, and

Figure 6 shows a number of the buoys in the barrier of Figure 1 on an enlarged scale.

DESCRIPTION OF PREFERRED EMBODIMENT

[0016] Figure 1 is a simplified plan view of an area which is protected using a floating security barrier according to the invention.

[0017] Figure 1 depicts a water body 10, for example at the sea, with an inlet 12 which extends into land 14. An installation 16 which is to be protected is situated on the land. A security fence 18 of any appropriate kind surrounds the installation on the land and extends to the water's edge. In order to protect the installation 16 against attack over the water 10 a barrier 20 according to the invention is positioned to float on the water between exposing extremities of the fence.

[0018] The barrier 20 is constructed using a plurality of buoys 24 each of the kind shown in Figure 2. Figure 3 illustrates a buoy 24 partly sectioned and Figure 4 shows on an enlarged scale and in an exploded configuration part of a fixing mechanism which is incorporated in the buoy.

[0019] The buoy 24 includes a buoyant body 26 and, a tie rod 28 which extends through the body and fixing mechanisms 30 and 32 respectively at opposed respective ends of the tie rod.

[0020] The body 26 is substantially spherical and is formed from a moulded outer shell 34 of polyethylene with a number of circumferentially extending grooves 36 in its outer surface. The grooves are spaced from and are substantially parallel to one another.

[0021] The tie rod 28 is made from stainless steel and is passed through a hole 40 in the shell which opposes a similar hole in the shell which is diametrically opposed to the hole 40.

[0022] The fixing mechanisms 30 and 32 are substantially identical to each other. Each fixing mechanism includes an inner plate 44, an outer plate 46 which is formed with a centrally positioned boss 48, a mounting plate 50 on an outer side of the outer plate, a stud 52 which projects outwardly from a central location on the mounting plate, a head 54 at an extremity of the stud, and a swivel connector 56 which is fixed to the stud. The swivel connector includes a bracket 58 and a U-shaped bolt 60, opposing limbs of which are threaded and passed through holes in the bracket. Nuts 62 are used to fix the U-bolt to the bracket.

[0023] The inner plate 44 is made in two or more parts so that the individual parts can be passed through the hole 40. The parts are then correctly positioned so that they are aligned with the outer plate 46. Thereafter threaded fasteners 66 are passed through registering holes in the outer plate 46 and in a flat portion 68 of the wall of the shell around the hole 40 and through holes in the respective part of the inner plate 44. Prior

to this an end 70 of the tie rod is engaged with an internal thread 72 on the boss 48. Bolts 74 secure the mounting plate and swivel connector to the plate 46.

[0024] Once the two fixing mechanisms have been securely linked to the tie rod marine foam 76 is injected into the interior of the shell 34 so that the interior is completely filled with the foam. The foam is allowed to set. Thereafter deterrent components 80 are engaged with the respective grooves 36. Each deterrent component is formed from an elongate strip of stainless steel from which barbs, spikes or similar formations are punched. The strips are positioned inside the grooves and opposing ends of each strip are fixed to each other to ensure that each strip circumferentially surrounds the body 26 and is held firmly in position.

[0025] In the arrangement which has been described the tie rod 28 is mechanically fixed to the opposing fixing mechanisms 30 and 32. Each mechanism in turn is fixed to the shell 34 using the fasteners 66. In this way the tie rod 28 is also fixed to the shell and, although the tie rod lies on a diametrical axis of the buoy, when rotation of the buoy takes place about the swivel connectors the tie rod rotates in unison with the buoy. This rotation is allowed for by the fact that the studs 52 pass through holes in the brackets 58 but are held captive to the brackets by means of the heads 54.

[0026] Figure 5 illustrates portion of a buoy 24A and portion of an adjacent buoy 24B. The buoys are interconnected by linking the U-shaped bolts 6OA and 6OB of the respective fixing mechanisms 3OA and 3OB to each other. It is evident from an inspection of Figure 5 that the buoys 24A and 24B can rotate relatively to each other about an axis 80 which passes through the respective tie rods 28A and 28B.

[0027] Although each tie rod is elongate and linear the connection shown in Figure 5, apart from allowing relative rotational movement between adjacent buoys, also permits pivotal movement of one buoy to another in substantially any direction. Thus the tie rods are not necessarily axially aligned with each other and are free to move according to water action which may affect the position of adjacent buoys, as is shown in Figure 6. This drawing depicts a number of buoys 24A, 24B, ...24N respectively which are interconnected in the manner shown in Figure 5 and which lie in the water 10. The number of buoys which can be linked in this way is not restricted for each buoy, in the water, is self-supporting. It is therefore possible to fabricate a floating barrier 20, as is shown in Figure 1 , to any appropriate length. Ends 82 and 84 of the barrier are anchored to the ground, as appropriate, to retain the barrier in a selected position while allowing a fair degree of movement of the barrier to take place as may be determined by water action.

[0028] The barrier has a number of important benefits. It is formed from buoys of spherical shape which provide a maximum volume, which is filled with marine foam, for a minimum surface area constituted by the shell 34. In the ocean water swells tend to move around the spherical body which thus presents a lower resistance to the water action. This in turn reduces stress and strain on the floating barrier.

[0029] The polymer shell, as noted, is mechanically secured to the fixing mechanisms and to the centrally positioned tie rod. Relative movement between component parts of the buoyant body and the tie rod is eliminated and this has been found to prevent the tie rod from damaging the foam and the shell.

[0030] The spherical buoy is less expensive to manufacture than a circular cylindrical buoy of the same diameter. On the other hand for a given quantity of construction material, a spherical buoy extends higher above the water surface and deeper below the water surface than, say, a cylindrical buoy. This makes it more difficult for an intruder to climb over, or swim underneath, a spherical buoy.

[0031] A further factor is that at the connection points between adjacent buoys the deterrent components on adjacent buoys are fairly close to each other. If a person attempts to pass through a gap between adjacent buoys there is a fair possibility that, as the buoys move with water action, the spikes or deterrent formations on the adjacent buoys will move closer towards each other and this can significantly impede possible passage of a person through the gap.

[0032] The swivel connectors are subjected to considerable force as water action causes the buoys to bob up and down or move to and fro. This results in wear of the U- bolts 60. These bolts are readily replaced however simply by either uncoupling the bolts from the brackets or by removing a mounting plate 50 together with the associated U-bolt and replacing the entire assembly.

[0033] The tie rods which are interconnected to each other by means of the fixing mechanisms essentially form a continuous metal link between the end points 82 and 84 of the floating barrier. The buoyant bodies on the tie rods carry the deterrent components and ensure that these are presented, at a desired position, above and below the water surface. As each buoy is free to rotate independently the buoy presents a significant obstacle to a person trying to climb over a buoy.