Field of the invention

[0001] The invention relates to a device and method to prevent marine fouling on a submerged ship hull by removing light, water, and oxygen from the hull surface.

Background

[0002] Marine growth and fouling on vessels and gear immersed in water causes reduced efficacy for a vessel and increased operation cost for an owner. Unattended, the growth and fouling may cause reliability issues and safety concerns. Certain types of vessels may not be used during large parts of the year due to seasonal limitations among professional vessels or weather limitations for leisure vessels. During these long seasons of standstill, the marine fouling will thrive.

[0003] Factors for marine fouling to thrive are, for example, oxygen rich water flow near the surface, light, and the structure of the surface. Due to the organisms need for light to develop and reproduce, different types of bottom paints are used to prevent growth, but the paint emit large amounts of toxic substances through leakage, which has very serious environmental consequences on the marine environment. Other methods to prevent fouling is to hoist the vessel out of the water for the entire off-season and store the vessel on land. This is costly and impractical for larger vessels.

[0004]There is therefore a need to prevent or remove the fouling.

[0005] In order to avoid this marine fouling and pollution of toxic substances, various proposals for solutions have been presented.

[0006] Document NO 342151 B1 discloses a disinfection floating raft comprising U shaped barge and a tarpaulin to be lowered or lifted by a lifting device to enclose a fluid volume to hold a vessel to be disinfected. The disinfection floating device is adapted to disinfect a fish farming vessel with chemicals. Document NO 342151 B1 has the disadvantage that it requires a lifting device to lift the tarpaulin and rigid outriggers and chemicals. Furthermore, the device disclosed is to disinfection after contamination and not long-term prevention of fouling.

[0007] Document NO 19984884 B1 discloses a device to prevent marine fouling an aft thruster part. The device compromises a sack 10 to be pulled over the thruster and a coat hanger shaped support 22 device to securely fasten the device to the thruster. Document NO 19984884 B1 has the disadvantage that the sack part is complex to fit l from light, and the device does not prevent water form and other factors for marine fouling to thrive.

[0008] Document W02011068416A1 discloses a system for disinfection of the outside of a vessel's hull comprising a sheet 3 and spacers 6 between the sheet and a hull for creating a layer containing a disinfection agent. Floating elements 7 are mounted on the sheet 3 in order to enable the sheet to extend all the way up to the surface of the water. The system may comprise an additional and separate top cover 11 that to prevent escaping gas. The sheet 3 is closed in the aft by using a winching mechanism to raise/lower the sheet. Chemicals may be introduced by diffusion hoses or pipes. Document W02011068416A1 has the disadvantage that it requires a winching mechanism to close the aft and the use of chemicals. Furthermore, the device disclosed is to disinfection after contamination and not long-term prevention of fouling by removing the factors for marine fouling to thrive.

[0009] Document EP 2310258 B1 discloses a tarpaulin with lower density than water that floats up due to enclosed microspheres in a foam and cover the submerges surface. The tarpaulin situates itself in proximity to the hull by way of buoyance and may comprise an opening for keels or the like to protrude out of the tarpaulin. The tarpaulin dos not forcefully enclose the hull to ensure that no light nor water may enter between the tarpaulin and the hulls surface. The tarpaulin does not ensure that water and oxygen is removed entirely from he surfaces of the hull, as no such means are provided.

[0010] Document US 2014290556 A1 disclose an inflatable tarp, which floats up from below to cover the hull. The solution require a system of poles for installing the tarp around the hull. Document JP 2003104285 A discloses a simple tarp to prevent fouling. The solution does not disclose a way of evacuating water between the hull and the tarp nor does it provide a watertight solution for enclosing the hull. The documents JPS59128095 A and AU2007101216 A9 discloses other known solutions for prevent marine fouling on a submerged ship hull.

[0011] It is therefore an aim of the present invention to overcome the shortcomings of the disclosed prior art and to provide an improved alternative to the prior art.

[0012] It is a further aim of the present invention to provide a to prevent marine fouling on a submerged ship hull by removing light, water, and oxygen from the hull surface. Short summary of the invention

[0013]The objective of the invention is obtained by the technical features of the appended patent claims.

[0014]The present invention relates to an anti-fouling device for a vessel or floating unit, the vessel of floating unit that comprise a hull partly or completely submerged in water. The anti-fouling device comprises at least a sheet that is configured to encompass the whole or parts of a vessels hull that is submerged in water, the sheet being comprised of a light and water impenetrable material. The main sheet comprises two longitudinal edges or border rims, wherein the two longitudinal edges are at a first ended of the main sheet fixed at a single point, and wherein the edges, extend along the main sheet to a second end. Furthermore, at least an inflatable element, attached to the main sheet, whereas the inflatable element extends along the length of both of the sheet edges, from the first end to the second end, the inflatable elements, comprises at least an inflatable chamber and at least an openable and closable opening for air to enter or exit the inflatable chamber. The inflatable element is adapted to push itself and thereby the main sheet against the hull when inflated, thereby creating a barrier impenetrable to light between the submerged part of the hull and the part above the water line. The device further comprises an openable and closable part situated between the two longitudinal edges, at the second end foldable attached to the main sheet at said second end protruding the inflatable elements at said second.

[0015] In an embodiment of the invention, the openable and closable part comprises a three-part foldable sheet, where a middle first part is foldable attached to the second end of the main sheet along a first crease line extending from one inflatable element to the opposing inflatable element at the second end, and a second part foldable attached to a first side of the first part along a second crease line and to the second end of the main sheet, and a third part is foldable attached to the first part along a third crease line opposite the second part and the second end of the main sheet, whereby the second and third part, is on opposing sides of the middle first part, all three parts protruding the second end, and wherein the openable and closable part further comprises fastening elements at least on the second and third part wherein the fastening elements comprises holes or loops for attaching members to be fastened.

[0016] In another embodiment of the invention the attaching members are ropes, lines or hawsers adapted to close and fasten the openable and closable part. [0017] In yet another embodiment of the invention the anti-fouling device comprises a conduit comprising a first and second end, the conduit extends from the first end at least a portion along the main sheet, wherein the conduit is at least partly fixed to the main sheet, wherein the second end is open into, and in fluid communication with, the side of the main sheet facing the vessel, wherein the first end is adapted for connection to a fluid pump to pump fluid from the second end, thereby being adapted to evacuate the fluid between the main sheet and the submerged hull.

[0018] In yet another embodiment of the invention a fluid pump is releasably fastenable to the first end of the conduit.

[0019] In yet another embodiment of the invention, the anti-fouling device comprises at least an open and closable fluid opening in the main sheet, the opening being adapted for water to exit the sheet and to connect a pumping device.

[0020] In yet another embodiment of the invention, a fluid pump is in fluid communication with the fluid between the main sheet and the submerged hull through a conduit and the fluid opening in the main sheet, to evacuate the fluid between the main sheet and the submerged hull.

[0021] In yet another embodiment of the invention, inflatable element at the first end of the main sheet comprises an substantially V- or U- shaped inflatable end element, the internal boundary of the V- or U- shaped inflatable end element being the two longitudinal edges, extending from the common first end.

[0022] In yet another embodiment of the invention, the inflatable chamber extends along both the opposing edges.

[0023] In yet another embodiment of the invention, the anti-fouling device comprises at least two inflatable elements each attached to, and extending along, respective edges of the main sheet from the first end to the second end, each inflatable element comprises at least an inflatable chamber, each comprising an openable and closable opening, for air to enter or exit the inflatable chambers.

[0024] In yet another embodiment of the invention the inflatable element is comprised of a flexible material.

[0025] In yet another embodiment of the invention the sheet is comprised of a flexible material thereby being adapted to conform to the hull. [0026] In yet another embodiment of the invention at least one weighted element is fastened to the sheet.

[0027] In yet another embodiment of the invention least two weighted elements are fastened to the sheet along the center line.

[0028] The present invention also relates to a method for protecting a vessel comprise a hull partly or completely submerged in water, using the ant-fouling device as disclosed herein, from fouling by removing water and light from the submerged hulls surface, the method comprises the steps of providing air into the openable and closable openings of the inflatable chamber by an air delivery device, thereby inflating the inflatable element at least partly with air and introducing by floating a floating vessel through the openable and closable aft part when the openable and closable part is in an open position, whereby the vessel is situated on top of the main sheet at least partially surrounded by the inflatable element, and closing the openable and closable part. The open and closable part is closed by folding the first part along the first crease line of the second end of the sheet thereby rotating the first part around a horizontal axis, and folding the second part along the second crease line along a vertical axis inn towards the opposing third part and over the first middle part, and folding the third part along the third crease line along an vertical axis inn towards the opposing second part and over the first middle part, and thereby fasten the attachment members to the vessel, the device or parts thereof. When the part is closed the next step is to evacuate the water between submerged hulls surface and the sheet a fluid pump, either inn fluid communication with the conduit or the fluid opening in the sheet, thereby removing light and water from the submerged surface of the vessels hull.

[0029] The present invention also relates to a method regarding the additional step of providing additional air into the openable and closable opening of the inflatable chamber until the inflatable element is pushed against the hull, thereby creating an barrier impenetrable to light between the submerged part of the hull and the part above the water line.

Brief description of the figures

[0030] Below, various embodiments of the invention will be described with reference to the figures, in which like numerals in different figures describes the same features.

Figure 1 shows the anti-fouling device seen from above.

Figure 2 shows the anti-fouling device seen from the side floating in the water together with a vessel. Figure 3 shows anti-fouling device seen from above with the openable and closable part comprises a three-part foldable part.

Figure 4a shows a bow portion of the anti-fouling device from the side with a see- through illustration of a conduit for emptying water.

Figure 4b shows a bow portion of the anti-fouling device from the side with a see- through illustration of a valve or opening for emptying water.

Figure 5a shows a bow portion of the anti-fouling device from above with two chambers.

Figure 5b shows a bow portion of the anti-fouling device from above with one chamber.

Figure 6 shows a cross-sectional view of the inflatable element.

Figure 7a shows the anti-fouling device seen from the side with a vessel situated within the device, with the openable and closable part open.

Figure 7b shows the anti-fouling device seen from the side with a vessel situated within the device, with the openable and closable part partially closed.

Figure 7c shows the anti-fouling device seen from the side with a vessel situated within the device, with the openable and closable part closed.

Figure 8a shows a cross-sectional view of the anti-fouling device with a vessel situated within the device and gap between the hull and the sheet.

Figure 8b shows a cross-sectional view of the anti-fouling device with a vessel situated within the device where the sheet is against the hull.

Figure 9a shows the anti-fouling device seen from above with the openable and closable part partially closed.

Figure 9b shows the anti-fouling device seen from above with the openable and closable part partially closed.

Figure 9c shows the anti-fouling device seen from above with the openable and closable part closed.

Figure 10 shows the anti-fouling device seen from the aft with a vessel situated within the device and s the openable and closable part closed. Detailed description of the invention

[0031]The following description will use terms such as "horizontal", "vertical", "lateral", "back and forth", "up and down", "upper", "lower", "inner", "outer", "forward", "rear", etc. These terms generally refer to the views and orientations as shown in the drawings and that are associated with a normal use of the invention. The terms are used for the reader's convenience only and shall not be limiting. When using said terms for the sheet, this should be understood as when the sheet or device is in use and floating in water in a horizontal and relative flat configuration. Like numerals on different drawings describe the same feature. Numerals with apostrophe represents an additional feature represented by the same numeral, for instance the number 10 will represent one or the first of multiple or all of the multiples, and the numeral 10' represents an additional of the same feature, like a second or multiple of the same feature.

[0032] Reference in the description to "one embodiment" or "an embodiment" means that a specific feature, construction, or characterization portion described in connection with one embodiment is included in at least one embodiment of the application object. Accordingly, the use of the term "in one embodiment" or "in an embodiment" at various locations in the specification will not necessarily refer to one and the same embodiment.

[0033] Figure 1 illustrates an embodiment of the invention where the anti-fouling device is seen from above. The sheet 2 is substantially shaped in the water plane shape as a vessel, with a substantially square aft end in the second end 7 and a bow portion in the first end 5 that merges to a single point 6. The sheet 2 is configured to encompass the whole or parts of a vessel's hull that is submerged in water and being comprised of a light and water impenetrable flexible material which is adapted to be shaped by the vessels hull, such as, but not limited to, fiber reinforced polyester, poly vinyl chloride (PVC) coted textiles and/or polyethylene (PE). The material may also be elastic. The word sheet is used herein but should be understood as any type of tarpaulin, canvas or the like that is impenetrable to both light and water, is substantially flat or thin and flexible. The sheet 2 comprises two longitudinal edges 3, 4 along the length of the sheet 2, the edges 3, 4 are joined at the first ended 5 of the main sheet 2 at a single point 6 adapted to receive the bow of the vessel. The longitudinal edges 3, 4 is opposing on each side of a center line 25. The two edges 3,

4 extends along the main sheet 2 to a second end 7 where they are spaced apart by the sheet 2 when layer flat on the ground or in the water. The sheet 2 may thereby be comprised of a substantially triangled shaped sheet or an "flat iron" shaped sheet or a triangled shaped portion and a rectangular shaped portion together. Attached to and extending along the edges 3, 4 of the sheet 2 are an inflatable element 8. The inflatable element may be one continuously inflatable element extending from second end 7 of the first edge 3 to the second end 7 of the second edge 4, thereby inflatable element extends along the length of both of the sheet edges 3, 4 from the first end 5 to the second end 7. The inflatable element may also be comprised of two inflatable elements 8, 8', wherein a first inflatable element 8 extends from the first end 5 along the first edge 3 and until the second end 7 and second inflatable element 8 extends from the first end 5 along the second edge 4 until the second end 7, as illustrated in figure 1. The inflatable element 8, 8' comprises at least an inflatable chamber 9 (illustrated in figure 6) and at least an openable and closable opening 10 for air to enter or exit the inflatable chamber 9. The inflatable element 8, 8' is adapted to push itself against the hull 26 when inflated by comprising a v shaped part 6 wherein angle of the inflatable element(s) 8, 8' at the first end 5 is less than the angle of the sheet 2 at the first end 5. Thereby, when not inflated, the give of the pliable un-inflated inflatable element 8, 8' allows for the angle of the two edged 3, 4 when they meet in a single point 5 at the first end, to be greater than when inflated. When the inflatable element 8, 8' are inflated, preferably through the openable and closable opening(s) 10, 10', the stiffness present in the v shaped meeting point will push the two edges 3, 4 toward each other. When a vessel is introduced into the device, the inflatable element(s) 8, 8' will be formyl pushed by the geometry of the v shape, close to the vessel hull when inflated, thereby creating a barrier impenetrable to light between the submerged part of the hull 26 and the part above the water line 11. The word v shaped herein is used substantially for any V- or U- shape, wherein the sides of the V or U being the beginning of the two longitudinal edges 3, 4 or the extension of the two inflatable elements 8, 8' from the common point. The substantially v- or u-shaped element is seen in figures 1, 3, 5a, 5b and 9a-c. The inflatable element 8, 8' and the inflatable chamber 9 may of an flexible material, the material may also be elastic as to allow for an expansion, thereby increasing the width or diameter of the inflatable element 8, 8' when inflated, closing the inflatable element 8, 8' into the vessels hull when the vessel is situated in the device. The device further comprises an openable and closable part 8 situated between the two longitudinal edges 3, 4 at the second end 7 foldable attached to the main sheet 2 protruding the inflatable elements at the second 7. When a vessel is to enter or exit the device, the vessel is introduced through the openable and closable part 20 and in between the two edges 3, 4 and the inflatable element (s) 8, 8'.

[0034] Figure 2 illustrates an embodiment of the invention where the anti-fouling device is seen from the side and floating in the water. The openable and closable part 20 comprises at least two positions, open and closed and a method for closing. In this illustration the openable and closable part 20 is illustrated in the open position, whereby a vessel 1 may enter the device, wherein the vessel 1 may be stored for a prolonged period of time to prevent the buildup of algae and marine fouling. The device may be deployed in the sea for vessels to be moored to buoys or it may be deployed in quays, piers or between floating docks. For the sheet 2 to receive the vessel 1, at least a weighted element 24 may be attached to the underside of the device to the sheet 2. For the device to be further adapted to the shape of the hull 26 before the vessel has entered, additional weighted elements 24 may be attached along the center line of the sheet 2. With the openable and closable part 20 in the open position the vessel is introduced into the device though the second end 7 between the two opposing edges comprising floating elements 8, 8'. The open and closable part 20 being comprised of a substantially flat, flexible and light and water impenetrable flexible material which is adapted to be shaped by the vessels hull, such as, but not limited to, fiber reinforced polyester, poly vinyl chloride (PVC) coted textiles and/or polyethylene (PE). The material of the open and closable part 20 may be the same as for the sheet 2.

[0035] Figure 3 illustrates an embodiment of the invention wherein the openable and closable part comprises a three-part foldable sheet 12, 13, 14, where a middle first part 12 is foldable attached to the main sheet 2 at the second end 7 along a first crease line 15, and a second part 13 is foldable attached to a first side of the first part 12 along a second crease line 16 and to the second end 7 of the main sheet 2, and a third part 14 is foldable attached to the first part 12 along a third crease line 17 opposite the second part 13 and the second end (7) of the main sheet. The second and third part 13, 14 are situated on opposing sides of the middle first part 12. The three parts 12, 13, 14, and thus the openable and foldable part 20, protrudes the second end 7. The openable and closable part further comprises fastening elements 18 at least on the second and third part as illustrated in figure 1. The fastening elements comprises holes or loops for attaching members 19 to be fastened. The attaching members are ropes, lines or hawsers adapted to close the openable and closable part, wherein the attaching members 19 may be attached to either the vessel, part of the device or a separate member such as a quay, dock, buoy, pier and/or a bollard to close the openable and foldable part 20 in accordance with the invention.

[0036] Figure 4a and 4b illustrated two device as disclosed wherein the device comprises a conduit 21 comprising a first end 22 and second end 23, the conduit extends from the first end 22 above the water line 11 at least a portion along the main sheet 2, the conduit may be fixed to the main sheet 2, wherein the second end 23 is open into, and in fluid communication with, the side of the main sheet 2 facing the vessel when the vessel is inside the device or the side facing upwards. The conduit 21 is any type of rigid, flexible, or semi-rigid pipe, tube or conduit suitable to transport fluid or air. The first end 22 of the conduit 21 is adapted for connection to a fluid pump (not shown). Thereby fluidly connecting the fluid pump with the fluid enclosed by the sheet 2. The pump is adapted to pump fluid from the second end 23 to evacuate the fluid between the main sheet 2 and the submerged hull of the vessel. When a vessel is situated inside the device and the openable and foldable part 20 is closed in accordance with the invention and the inflatable elements 8, 8' are inflated and thereby closely pushed close to the surface of the vessels hull, the pump can evacuate the fluid between the sheet 2 and the hull via the conduit 21. This removes the fluid, instance the sea water from the surface of the hull together with shutting out the light. The suction from the pump will create a vacuum removing trapped fluid and air. When all fluid is removed, the sheet 2 acts as a protective layer on the hulls surface removing many of the factors that are necessary to be present for marine fouling to thrive are, for instance, oxygen rich water and sun light. This way the vessel may be stores in the sea for a prolonged time when the device as in accordance with the invention is encompassing the vessel. In figure 4a the conduit 21 is on the inside of the device i.e. on the side of the sheet 2 towards the vessels hull or the side facing upwards. In this embodiment the conduit 21 does not need to penetrate the sheet 2. Figure 4b illustrates an embodiment where the conduit 21 is situated on the outside of the device, i.e. on the side of the sheet 2 away the vessels hull or the side facing downwards. In this illustrated embodiment the conduit 21 or the opening at the second end 23 must penetrate the sheet 2.

[0037]The fluid pump is releasably fastenable to the first end 22 of the conduit 21. In figure 4b the device comprises at an open and closable fluid opening 27 in the main sheet 2 for the conduit 21 or parts thereof to enter from the outside and into the inside, and thereby for water to exit the sheet 2 through a pumping device. The pumping device to remove fluid, such as water or sea water, from inside the device may be any type of pumps suitable for pumping and/or extracting fluid, such as impulse pumps, velocity pumps, gravity pumps, steam pumps and valveless pumps, displacement-, centrifugal- or axial-flow pumps. The pump that is used to inflate the inflatable elements may be any type of suitable air delivering device or pump such as any displacement-, centrifugal- or axial-flow pump or instrument air.

[0038] Figure 5a and 5b illustrates the bow part of the device as seen from above. In figure 5a the inflatable element is comprised of two inflatable elements 8, 8', a first inflatable element 8 that extends along the first edge 3, and a second inflatable element 8' that extends along the second edge 4. The first and second inflatable element 8, 8' are adjoiningly attached to each other at the first end 5, extending aft from said first end 5. The first and second inflatable element 8, 8' each comprise an open and closable opening 10, 10' for adding and/or removing air from the inflatable elements. The first and second inflatable element 8, 8' are fluidly disconnected and adjoined with a reciprocal angle that forms the V or U shape of the single point 6. In figure 5b the inflatable element is comprised of one inflatable element 8 comprising one inflatable chamber 9 that extends along both edges 3, 4 of the sheet 2. The inflatable element 8 comprises a substantially V or U shape at the point 6 at the first end of the sheet 2.

[0039] Figure 6 illustrates a cross section view of the inflatable element 8 comprising an open and closable opening 10. This may be a valve, free of hinged plug and/or screw cap-type element that is known to a person skilled in the art. The inflatable element 8 surrounds the inflatable chamber 9. In an embodiment of the invention the inflatable element 8 is comprised of a flexible and stretchable material. The amount of air within the inflatable chamber 9 thereby determines the width and/or cross section area of the inflatable element 8. If the inflate elements or parts of the device thereof does not situate closely, meaning touching, the hull of the vessel 1 around the sides of said vessel due to the shape of the hull in relation to the sheet and said inflatable element(s) 8, 8', more air may by filled into the inflatable chamber 10 to increase the width and/or cross section area of the inflatable element 8 until a satisfactory seal is achieved between the inflatable element(s) 8, 8' and the hull of the vessel.

[0040] In figure 7a, 7b and 7c the device is illustrated with the vessel 1 situated within the device from the side. In figure 7a the open and closable aft end 20 is open, which should be understood as laid flat in the water protruding aft of the bow. Both the device and the vessel 1 is buoyant and floating in a body of water with a waterline 11 dividing the hull of the vessel 1 into a submerged part bellow the water line 11 and a dry part above the water line 11. The with i.e. the distance between the edges 3, 4 of the sheet 2 determined the how deep bellow the water line 11 the sheet will 'hang' when the edges 3, 4 are lose to the side of the vessel 1. As the water inside the device, between the sheet and the hull, is evacuated, the sheet may be substantially larger in both width and 'hanging' depth as the sheet will be sucked by vacuumed to the hull when the water is removed. In the figures 7a-7c two weighted elements 24 is attached to the sheet 2 to create an open passage for the vessel 1 enter. If the vessel comprises keels or deep rudders or the like, the device must be adapted to receive the vessel by way of sizing the sheet and device. In figure 7b the 7a the open and closable aft end 20 is partly closed wherein the first part of three-part foldable sheet 13 is positioned from a horizontal position, as illustrated in figure 7a, to a vertical position. In figure 7c the open and closable aft end 20 is closed and no water may enter or exit the aft end i.e. the second end, of the device through the open and closable aft end 20. Said open and closable aft end 20 when closed, prevents water to enter or exit the inside of the device through the open and closable aft end 20, and the water trapped between the vessels 1 hull and the sheet 2 may be evacuated via the conduit 21 and a pump.

[0041] Figure 8a and 8b illustrates a cross section view of the anti-fouling device across a middle part as illustrated by line A in figure 1, with a vessel situated within the device. In figure 8a the sheet 2 is freely hanging in the water and submerged, with aid from the weighted element, to a depth defined by the width of the sheet 2 and the width between the inflatable element(s) 8, 8'. The depth of the deeps part of the sheet 2 is the center line 25 where the opening at the second end 23 of the conduit is situated. In figure 8a there is a gap between both sides of the vessel 1 between the vessels 1 hull 26 and the sheet 2 and between the vessels 1 hull and the inflatable element(s) 8, 8'. Said gap between the vessels 1 hull and the inflatable element(s) 8, 8' will let sunlight to enter and shine on the submerged part of the vessels 1 hull that together with the oxygen rich water between the vessels 1 hull and the sheet 2 would normally let the algae and the like to thrive. It is therefore an object of the invention to have the means to remove said gaps according to an embodiment of the inviting. In figure 8b the sheet 2 is situated next to the submerged part of the vessels 1 hull and no water or fluid is located in between said elements. Furthered, the gap or opening visible in figure 8a between the vessels 1 hull and the inflatable element(s) 8, 8' is gone, and no light may shine on the submerged hull. This has been achieved by a method according to the invention. In the state that is illustrated in figure 8b, a vessel may be stored for a prolonged period of time without the hulls surface being fouled by marine growth. This period may be from a number of days to several years

[0042] Figure 9a, 9b and 9c illustrates the anti-fouling device as seen from above with the open and closable aft end 20 in three different states or positions. In the figure 9a the device is in a position after the first part of three-part foldable sheet 12 firstly being folded or rotated at the first crease line 15 at the second end 2 of the main sheet 2. This position is illustrated in figure 7b as seen from the side.

[0043] In figure 9b the device is positioned as illustrated in figure 9a with the addition of the second part of three-part foldable sheet 13 being folded or rotated at the second crease line 16 and with an attachment member 19 attached in a first end at an attachment element 18 in the second part of three-part foldable sheet 13 and in another end at the opposite positioned inflatable element 8.

[0044] In figure 9c the device is positioned as illustrated in figure 9b with the addition of the third part of three-part foldable sheet 14 being folded or rotated at the third crease line 17 and with an attachment member 19 attached in a first end at an attachment element 18 in the second part of three-part foldable sheet 14 and in another end at the opposite positioned inflatable element. In figure 9c the open and closable aft end 20 of the device is closed for said vessel 1 to enter or exit and for water to enter and exit through said aft end 20.

[0045] Figure 10 the anti-fouling device is illustrated as view from behind, wherein the open and closable aft end 20 is in a closed position. The first and second part of three-part foldable sheet 13, 14 if folded towards each other on top, or on the about side, of the first part of three-part foldable sheet 12, that is folded or lifted up with its end above the water line 11, creating a water tight seal. In this figure the two attachment members 19, 19' are attached two respective attachment elements 18, 18' and to the vessel 1. The attachment members 19, 19' crosses over the diagonal of the vessel from where each respective attachment members 19, 19' is attached to the open and closable aft end 20 at respective attachment elements 18, 18'. This securely fastens the first, second and third part of three-part foldable sheet 12, 13 and 14 in a manner closing the open and closable aft end 20.

[0046] It is provided a method of closing the open and closable aft end 20 of the device with the vessel situated within. From the position illustrated in figure 9a with the vessel situated inside the device, which should be understood as located within the boundaries of the device, and with the closing the open and closable aft end 20 open in the horizontal position. The method comprises the steps of closing the openable and closable part 20 by folding the first part of three-part foldable sheet 13 along the first crease line 15 that traverses along the second end 7 of the main sheet 2, thereby rotating said first part 13 around a horizontal axis defined by the first crease line 15, and; folding the second part of three-part foldable sheet 14 along the second crease line 16 along a vertical axis defined by the second crease line 16 inn towards the opposing third part of three-part foldable sheet 14 and over the first middle first part of three-part foldable sheet 12, and folding the third part of three- part foldable sheet 14 along the third crease line 17 along the vertical axis defined by the third crease line 17, inn towards the opposing second part of three-part foldable sheet 13 and over the first middle part 12, and securing the attachment members 19 to the vessel, the device or parts thereof thereby arriving at a position where the open and closable aft end 20 is closed as illustrated in figure 9b, 9c and 10. The open and closable part 20 may be opened if closed, by reversing the closing method disclosed above.

[0047] Furthermore, herein is disclosed a method for protecting a vessel comprise a hull partly or completely submerged in water, from fouling by removing water and light from the submerged hulls surface, the method comprises the following steps providing air into the openable and closable opening(s) 10 of the inflatable chamber by an air delivery device (not shown), thereby inflating the inflatable chamber(s) 9, 9' at least partly with air. The device may comprise one or multiple inflatable chambers 9, 9'. Then introducing a floating vessel 1 through the openable and closable aft part 20 when the openable and closable part 20 is open, whereby the vessel 1 is situated on top of the main sheet at least partially surrounded by the inflatable element 8, 8', and; closing the openable and closable part 20 as disclosed above. With the vessel with the device and the openable and closable part closed 20, an fluid pump is attached to the first end 22 of the conduit 21 and fluid pump is activated to evacuate the water between submerged hull of the vessel 1 and the sheet 2 by said fluid pump. With the water between submerged hull of the vessel 1 and the sheet 2 removed, the vessel may be stored floating for a prolonged period of time without the hulls surface being subjected to marine fouling.

Reference numerals

1 vessel

2 main sheets, tarpaulin

3 first longitudinal edge of sheet 4 second longitudinal edge of sheet

5 first end of sheet

6 single point, V shaped point of inflatable element 7 second end of sheet

8, 8' inflatable element, first and second inflatable element 9 inflatable chamber inside inflatable element

10, 10' open and closable opening 11 water line 12 first part of three-part foldable sheet 13 second part of three-part foldable sheet 14 third part of three-part foldable sheet

15 first crease line

16 second crease line

17 third crease line

18 fastening elements 19 attaching members

20 open and closable aft end, open and closable part 21 conduit 22 first end of conduit 23 second end of conduit 24 weight element

25 center line

26 hull of vessel below waterline 27 opening in the sheet