Technical Field

The present invention regards a system and a method for preventing unauthorised access to a vessel and more particularly a guard rail for preventing e.g. pirates for accessing and entering a vessel.

Background of the invention

Piracy is an escalating problem for the shipping industry the world over. Estimates of the direct and indirect costs of piracy to global trade range as high as $16 billion annually. The preferred method for hijacking a vessel is to use small high speed boats that come up alongside the vessel. By attaching ropes or ladders to the railing of the vessels, they are able to force their way onto the ship. Once on-board they use guns to hijack the crew and the vessel.

They attach the ropes and ladders to the railings by either throwing grappling hooks over the railings or by attaching hooks to the railings by fastening them to long poles.

At the present moment there are few measurements a vessel can use to protect itself against attack. One solution is using non-lethal force against the attackers. Such solutions are e.g. water cannons, sound cannons, electrical fences or the like. Other solutions are patrolling the areas with high frequency of attacks from pirates by armed forces.

These solutions are either dangerous or costly. Dangerous because of the risk of armed confrontation between the two parties or costly because of the costs related to the need for armed forces patrolling the dangerous areas. A solution to the problem is to prevent pirates or the like from entering the vessel using a safe and relatively cheap method of protection.

As it is today, passive measurements for preventing capture and hijacking of vessels are few. From FR 2949430 it is known a fence for preventing pirates from entering the vessel. The fence comprises a plurality of sections that can be attached to the railing of a ship. Each section comprises two main parts in the form of, a first plate extending over the railing and down the outside of the vessel. A second plate attached to the top of the first plate with a hinged. This second plate extends upwards at an angle slanting inwards towards the ship. This is to make it hard or impossible for pirates to throw or attach hooks to the railings. The main point is that the top plate gives way when strain is put on the rope or ladder. A problem with this solution is that it is unnecessarily complex and takes up a lot of space when it is not in use. Another problem with this solution is that the construction makes it possible overcome the barrier by using two sets of hooks.

Summary of the invention

It is therefore an object of the present invention, as it is stated in the set of claims to overcome the problems mentioned above. This is done by creating a security fence made up of a plurality of separate sections. The sections are placed next to each other in a continuous fashion around the railing of the entire vessel. Each section comprises two plates.

The first plate is, at least at the top, attached to the railing of the vessel. The plate extends downwards along the outside of the railing. The second plate is attached to the top of the first plate with a hinge. The second plate is further slanting outwards form the ship creating an angle between the first and the second plate between 90° - 180°.

The two plates are hinged together and spring-loaded in such a fashion that if a hook is thrown over the top plate it will give way and the hook falls of. After the hook has fallen of, the top plate returns to its original position.

Further, the spring function can be deactivated by pushing in a button. The two plates than folds together and can easily stowed away when it is not in use.

Brief description of the drawings Figure 1 is a perspective view of a preferred embodiment of the present invention.

Figure 2 is a drawing of a preferred embodiment of the present invention mounted on a vessel.

Figure 3 is a drawing of how the present invention works.

Figure 4 and 5 is a detailed drawing of the spring loaded system according to an embodiment of the present invention. Figure 6 is a detailed drawing of a preferred solution of the spring loaded connecting the two plates together.

Figure 7 and 8 are alternative solutions for how the two plates are placed in relation to each other. Detailed description

Figure 1 is a perspective view of a preferred embodiment of the present invention. Here it can be seen a section of the fence. The section comprises two main parts. Each part is in the form of a square plate 101, 102. The two plates 101, 102 are hinged 104 together. The two plates 101, 102 have a spring function that can be activated or deactivated by the push of a button 404. The spring function acts in such a way that when activated, the two plates 101, 102 are kept at a certain angle to each other.

When the spring function is deactivated the two plates 101, 102 can be folded together. At the back of at least one of the two square plates 101, 102 it is placed at least one set of hooks 103.

In a preferred embodiment of the present invention both of the plates 101, 102 are similar. This means that they are of the same shape and size and both have at least one set of hooks 103. Alternative embodiments may have several sets of hooks 103 or they can have any other form of device for securing that section of the fence to the side of the vessel or any combination of devices for fastening that section of fence to the side of the boat.

The plates 101, 102 are preferably made of a stiff lightweight material, e.g. plastic, composite materials, lightweight metals e.g. aluminium, or Kevlar or carbon fibre materials.

Figure 2 is a drawing of a preferred embodiment of the present invention mounted on the side of a ship 201. Here it is shown how the set of hooks 103 on top of the first plate 101 grips around the top of the railing 202. Further the first plate 101 extends downwards on the outer side of the railing 202 and down the side of the vessel 201. The second plate 102 extends outwards from the vessel 201. The two plates 101, 102 create an angle to each other of between 90° and 180°.

Figure 3 is a drawing of the present invention showing how the invention works when an unauthorized person tries to attach a hook 301 to the side of the vessel. The hook 301 is attached to the top of the second plate 102. When tension is put on the hook 301 the second plate 102 is pulled down and the hook 301 slides of. When the hook 301 has fallen of, the second plate 102 swings back to its original position.

Figure 4 and 5 is a detailed cross section of the spring loaded system according to a preferred embodiment of the present invention. In figure 4 one side of the spring loaded system is shown. In the centre of the joint it is placed a torsion bar 401.

This torsion bar 401 provides the spring action between the two plates 101, 102.

When force is exercised on one of the plates 101, 102, the tension bar 401 twists around its axis. When force is no longer exercised on one of the plates 101, 102 the tension bar 401 goes back to its original position.

In both ends 406, 501 the tension bar 404 is bent at an angle of about 90°. The bent ends 406, 501 fits into a corresponding slot 405, 502 at each end that locks the torsion bar 401 in place.

At the end of the joint shown in figure 4 it is placed a button 404. This button 404 activates or deactivates the spring loaded system. This button 404 is hollow and has a circular base. The base of the button 404 is attached to a disc 403 with at least one slot 405. This disc 403 is spring loaded 402 pushing both the disc 403 and the button 404 outwards. Between the disc 403 and the button 404 there is a hollow space 407. When the button 404 is in its original position, the bent end 406 of the torsion bar 401 fits into one slot 405 in the disc 403. When the button 404 is pushed in, the bent end 406 of the torsion bar 401 fits into the hollow space 407 between the button 404 and the disc 403. The spring loaded system is then deactivated. When the button 404 is pushed in, deactivating the spring loaded system, the two plates 101, 102 can be moved freely around the hinges joining the two plates 101, 102 together.

The disc 403 has either two or more slots 405 the bent end 406 of the torsion 401 fits into, or it can have one larger slot 405 where the bent end 406 of the torsion bar 401 fits into either end of the slot 405. This makes it possible to fix the two plates 101, 102 in certain angles to each other, preferably folded together for storage or activated for use.

Figure 6 is a detailed drawing of a preferred solution of the spring loaded system connecting the two plates 101, 102 together. Here the spring function is given by a torsion bar 401.

There are other ways to facilitate the spring loaded system . These can be, using a coil spring, a compression spring, intelligent material or a hydraulic spring .

Figure 7 and 8 are alternative solutions of how the two plates 101, 102 can be placed in relation to each other.