Abstract:
A floating device for transfer of personnel and material to and from the shore, where the device is divided into sections that are mutually brought together by articulated couplings to form an extended, continuous path for the transfer of said personnel and material, as the sections are set up to be reset between a parked, folded position and an extended, using position. The device is characterized by a first section ( 10 ) that comprises mutually separated hull sections ( 14, 16 ) that are connected via a deck ( 12 ) where the other sections ( 20, 30 ) in the device are set up to be parked in under the deck ( 12 ) between the hull parts ( 14, 16 ) of the first section ( 10 ), and also that the device comprises means to securely couple the other sections ( 20, 30 ) to the first section ( 10 ) up under the deck, as the hull parts can be ballasted to be able to raise and lower the first section ( 10 ) with regard to the other sections ( 20, 30 ).

Description:
The present invention relates to a floating device for the transfer of personnel and material to and from a landing site (a beach) where the device is divided into sections that are mutually folded with articulated couplings to form an extended continuous path for transfer of said personnel and materials, as the sections are arranged to be re-set between a parked, folded state and an extended, using state. 
     In more detail the invention relates to a new device to transfer personnel and equipment, usually heavy, rolling equipment, onto land or on board a ship where there are no harbour facilities. 
     Furthermore, the invention relates to an application of the device to serve a vessel. 
     The type of vessel to which the invention relates is often called a landing vessel to place personnel, vehicles or other material on a beach or the like. 
     The present invention is particularly related to situations where cargo shall be brought on board or ashore from a ship that lie some distance from land (the beach). 
     BACKGROUND OF THE INVENTION 
     Such a vessel often has the form of a barge or loading pram that can be described as a floating platform (or loading) box that can be driven with or without its own drive unit. Normally these have a flat bottom. The cargo is transferred between land (the beach) and the vessel with the help of ramps or skids, or the barge can be partially driven onto, for example, the beach. Such vessels are also equipped with their own propulsion engine. The shape of the hull is typically flat, something which makes them applicable in still waters and in shallow waters. 
     An example of such a situation is described in WO 2011/005112 where a foldable, floating gangway, composed of individual sections, that runs from an anchoring site on land and out to a ship anchored some way out to sea. The gangway can be folded completely horizontally in a space saving way when it is parked and inactive. 
     Moreover, reference is made to U.S. Pat. No. 5,573,363 which describes a raft construction where the one outermost section in such an articulated construction is a raft section that is anchored. The construction lies in a zigzag pattern over the sea up to the raft construction. Furthermore, reference is made to the publication RU-513902. 
     Through the ages unloading or loading a ship has presented large challenges and many resources have been used to tackle these challenges by building large, costly harbour installations. It has always been particularly challenging to get warships and transport ships unloaded in connection with landing operations during a war. 
     Existing harbours in the area will then, in many cases, be damaged, have mines laid or have a military protection in the form of many different weapon systems, something which makes it impossible or unacceptable because of the risk of large losses, to use existing harbours in the area. Therefore it is an indisputable wish to be able to find alternative sites in the vicinity to set ashore troops and heavy military equipment without having to risk unacceptably heavy losses. 
     THE AIM OF THE INVENTION 
     It is an aim of the invention to provide a new construction for a barge to transfer personnel and cargo to and from the shore. For example, to form a transport connection between the shore and a ship at roadstead, for example, between two ships. This invention tackles this challenge. 
     It is a further aim of the invention to provide a construction that is very compact when in a storage position where the sections are coupled tightly to each other, but they can be unfolded to an extended using position. 
     Furthermore, it is an aim to couple a number of the sections in under a deck surface of a catamaran-mother section and then to lift the sections up above the water line by a suitable ballasting of the catamaran hull parts in the mother section. 
     PRESENT INVENTION 
     The device according to the invention is characterised by a first section that comprises mutually separated hull parts that are connected via a deck where the other sections in the device are set up to be parked in under the deck between the hull parts of the first section, and also that the device comprises means to securely couple together the other sections to the first section underneath the deck, as the hull parts can be ballasted to be able to raise and lower the first section with regard to the other sections. 
     It is preferred that the first section is a catamaran with a deck and longitudinal hulls that can be ballasted which comprises propulsion machinery to drive it forward in the sea. 
     It is particularly preferred that the underside of the deck of the first section and the topside of the second section comprise collaborating gliding/steering bodies to lead the second section in and out from under the deck between the two catamaran hulls. 
     According to a preferred embodiment the collaborating gliding/steering bodies are made up of a longitudinal, undercut groove in the underside of the deck in which an enlarged head of an upwardly extending peg in the topside of the section in its one end is set up to run, and also that the end of the groove comprises a stopping body to prevent the peg/head from gliding out of the groove. 
     According to yet another preferred embodiment said gliding/steering bodies make up the coupling between the first section and the second section when the section is extended into the using position. 
     The means to couple together the other sections to the first section under the deck preferably comprises that the underside of the first section and the topside of the other sections comprise mutually connectable male and female bodies and associated locking bodies that can be dismantled, to fasten the section underneath the deck. 
     It is particularly preferred that the collaborating male and female bodies comprise pegs set up to be led into respective channels, whereby they are locked together with the help of locking latches on the topside of the deck of the section. 
     Furthermore, it is preferred that the catamaran section can be raised by the removal of water from the catamaran hulls so that the fastened sections are, in their entirety, lifted above the waterline. 
     It is preferred that the sections are fitted with one or more propulsion propeller units that can, for example, be turned. 
     According to a preferred embodiment, the outer section is fitted with one or more propeller units which can be, for example, side propeller units. 
     The catamaran section is preferably made up of a mother section and also two further floating sections linked together via hinged joints end to end, as the outermost (the third) section is the one that is coupled to land. 
     The outermost, third section is preferably fitted with a belt unit that makes it possible to drive parts, or the whole, of the section up on dry land when they hit the sea bed during the drive towards the shore. 
     Furthermore, it is preferred that the outermost section is fitted with a winch unit to pull the outermost section up on land. 
     According to the invention, the device is applied to form a gangway connection between a ship and the shore, in that the mother/catamaran section is connected to the ship, while the other sections are stretched out towards the shore where the outermost section is anchored for the transport of personnel between the shore and the ship. 
     The concept according to the invention comprises a number (in particular three) of sections that are connected end to end in a row with the help of associated swing disc joints. The joints have a certain similarity to the swing disc joints which one finds today in trailers that shall be connected to a hauling wagon, for example, in different types of road trains. 
     In particular, the concept is comprised of three sections including the mother section. 
    
    
     
       FIGURES TO SHOW THE INVENTION 
       The invention shall be explained in more detail with reference to the enclosed figures, in which: 
         FIG. 1  shows a perspective of the inventive construction seen at an angle up from the underside and is comprised of three floating sections that are respectively coupled together end to end. 
         FIG. 1A  shows how a gliding connection between the mother section and the connected section can be made. 
         FIG. 2  shows a perspective corresponding to the construction seen at an angle down from the topside. 
         FIG. 3  shows an enlarged perspective of the end section facing land. 
         FIG. 4  shows how the construction is used to transfer cargo/personnel between the shore and a ship out on the sea. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The invention shall now be explained in more detail with reference to  FIG. 1 . 
     The construction comprises three extended floating sections  10 ,  20  and  30  that are coupled together end to end, respectively, to float on the sea. The sea line is shown by the reference number  11  in  FIG. 2 . 
     The one section  10  is set up to take up and store the other sections  20  and  30  in a compact setting, in the case shown there are two sections. The section  10  comprises an upper deck  12  for placing of the cargo, while its underside comprises a number of float elements along each side edge so that a space  15  is formed between these to take up the other elements during storage. According to a preferred embodiment, the float elements are formed by two longitudinal hollow hull sections  14  and  16 , respectively, so that the section  10  appears as a catamaran construction. 
     The section  10  can be described as a mother section as it is this section that shall store the other sections and it encompasses a propulsion system. 
     Closed separate machine rooms for propulsion machines, such as for propeller operation or water jet operation, are arranged in each hull  14  and  16 . According to an example, the propulsion machine is designed to be able to give the catamaran a propulsion/speed of up to 20-30 knots. 
     The other parts of the hollow hull parts  14  and  16 , respectively, define buoyancy tanks/ballast tanks. The tanks  14 , 16  are ballasted suitably with water with the help of pumping bodies, so that the catamaran can be raised and lowered in the sea. Thus, water is let into or pumped out of the tanks  14 , 16 . For example, when the deck  12  in the construction carries a lot of cargo, the tanks can be completely filled with air, i.e. all the water is pumped out and replaced by air. 
     Thus, the section  10  is a catamaran construction comprised of two separate hulls  14  and  16  which between them carry a deck  12  that lies above the water surface. Furthermore, on top of the deck is a wheelhouse (not shown) with the necessary equipment to serve all functions, such as propulsion machinery, ballasting pumps and ballasting valves and operation of the coupling means to fasten the sections  20  and  30  to the mother section  10 , and also flaps for going ashore. The deck between the two hulls is, for example, a trusswork strengthening construction with an upper deck surface  12  and can have a thickness of about 1 meter. 
     According to an example, the catamaran can have a length of 110 meters and a width of 20 meters, where each hull has a width of 4.5 meters and the distance between the two hulls is 11 meters. 
     The underside  17  of the deck  12  comprises a longitudinal guiding groove  22  to set up a glide fastening in connection to the section  20 , such as in the form of an undercut groove, set up to take up a rounded head  24  on a bolt  26  that extends up from the topside of the end of the section  20 . This functions corresponding to a bolt/swing disc as a glide fastening that goes on the underside of the catamaran section  10  along the whole of its length. This constitutes an introductory coupling between the section  10  and the section  20  for the going in and out of the section  20  in under the section  10 . The groove  22  comprises a stopper so that the section  20  cannot be pulled completely from the section  10 . 
     When the section  20  shall be stored in the section  10 , it is pushed in between the catamaran hulls  14  and  16 , as the bolt head  24  is led forward in the undercut groove  22 . Thereby, a controlled pushing in of the section  20  is obtained in under the section  10  under the deck  12  and between the catamaran hulls/catamaran chambers  14  and  16 , respectively. 
     Based on this it appears that the floating barge section  20  is narrower than the distance between the hulls  14 , 16 , i.e. less than 11 meters when one follows the dimension example above, such as a length of 25 meters and a width of 10 meters. The section  20  can also be ballasted with a mixture of air and water to achieve a correct floating position in the sea. 
     Furthermore, the section  20  can be fitted with one or more azimuth thrusters  8  that extend down into the sea under the bottom of the section  20 . This thruster  8  is used to manoeuvre the section  20  out of and in to the underside of the section  10  and otherwise in other positions. 
     A series of upwardly extending bolts  7  are fitted on the topside of section  2 , along each side, the lengths of which are longer than the thickness of the deck  12 , between the hulls  14 , 16  of the catamaran. These bolts  7  are adjusted to existing holes  3  in the deck  12  of the catamaran  10 . When the section  20  glides in between the hulls  14 , 16  and the gliding bolt  24  comes to its forward position, the bolts  7  are level with the openings  3  in the deck. In the lowering down of the section  10  at a suitable ballasting, the bolts  7  glide up in the holes  3  and lock the section  20  to the section  10  in a stable assembly. Gripping pegs (not shown) can also be mounted in the section  10 , that grip around the upwardly extending bolts  7  so that the section  20  is securely locked to the underside of the mother section  10 . 
     The raising and lowering of the sections  20  and  30  for fastening to the mother section  10  can also be carried out in that the sections  20  and  30  are raised up under the deck  12  by the pumping out of water. 
       FIG. 2  shows a hinged flap/plate  27  that forms a level transition between the top deck  12  on the first section  10  and the top surface of the second section to simplify traffic and transfer of personnel/cargo between the two sections. 
     Section  30   
     The third section in the row is shown by  30 , and is also a floating section that can be ballasted, having approximately the same width as section  20  so that it can also be placed in between the hull parts  14  and  16 , respectively, in the section  10 . However, the section  30  is fastened to the end of the section  20  (the middle section) by a swing disc joint  9  or a universal joint corresponding to the fastening between the section  10  and the section  20 . However, the section  30  has no gliding path for the leading in between the catamaran hulls in the section  10  as it is suspended in the end of the section  20 . The section  30  is fitted with a side propeller unit  112  ( FIGS. 2 and 3 ) and upwardly extending bolts  7 ′ corresponding to the bolts  7  on the section  20 , with associated holes in the deck of the section  10 . As the section  30  is fixed to the section  20  via the swing disc joint  9 , it is pulled behind the section  20  when this is driven in between the catamaran hulls  14 - 16  in the section  10 . When the bolts  7 ′ are in place they will be forced up through the through-running holes in the deck  12  on the section  10 , and when these are locked with the help of locking latches (not shown) both the sections  30  and  20  are securely fastened in under the mother section  10 . 
     When the mother section is sufficiently raised in the sea by an appropriate ballasting, the two other sections can be completely lifted up from the sea  11 , and the mother section can be driven in the sea by the propulsion machinery without the connected sections dragging in the sea and generating a resistance to the propulsion, when it shall run, for example, at a speed of up to 20 knots in the sea. This is one of the aims of the inventive construction. 
     In addition, the forward free end of the section  30  is fitted, at its bottom edge, with a continuous caterpillar belt unit  31 , i.e. comprising two continuous belts  34  (one on each side) that run over the rear and forward drive wheels  38   a  and  38   b , respectively, and the lower guiding wheels against the foundation. 
     A hydraulically hinged trap door  40  is fitted over the belts on the deck  35  of the section  30 , that can be raised and lowered as the trap door  40  is placed in towards land  50 . 
     As a consequence of what is described above, the sections  20  and  30  can be pulled in under the section  10  (the catamaran). The section  10  is then first raised some by an appropriate emptying of water and inflow of air so that there is room for both the section  20  and the section  30 , as these are led in under the section  10  between the catamaran hulls  14 , 16  with the help of the propeller units shown. 
     Thereafter, the section  10  is lowered again by a new filling of water, again so that the bolts on the sections  20  and  30  are fed up through the holes  3  in the deck  12  on the section  10  and are locked on the topside with the help of said locking latches. Thereafter, the section  10  can again be raised by replacing water by air inside the pontoons  14 , 16  and the sections  20  and  30  are raised upwards again as they hang fixed under the deck  12  of the section  10 . 
     In this mode, the assembled sections  10 , 20 , 30  can be transported. 
     A Practical Embodiment Example 
     When the construction is used in connection with a military landing, we can imagine the following scenario: 
     It is decided that the military landing shall take place on a deserted beach, where the bottom slopes very gradually. A series of transport ships in a convoy are on their way to the actual site, together with the usual military support units. 
     In the convoy, there is also a construction according to the invention. When the construction arrives at the beach where the landing shall take place, it lies in a position about 300 meters from the shore. The inventive construction is lowered by letting in water and the locking bolts that fix the sections  20  and  30  are released and the section  10  raises itself again. The sections  20  and  30  are pulled out from the aft end of the section  10 . The swing disc joint between the sections  10  and  20  is locked in the correct position. The angle between the three sections, for example, as a zigzag pattern as shown in  FIGS. 1 and 4 , is set and the sections are moved in towards the beach with the section  30  in front to perform the landing. To keep the correct position and angles, all propeller systems associated with the sections are used. 
     Closer to the land shore, the caterpillar belts at the end of the section  30  will hit the bottom  52  ( FIG. 3 ) and they are then activated to roll and will pull the section  30  so far up on the beach as is required. Thereafter, the hydraulic trapdoor  40  is lowered down onto the beach. 
     If it is necessary, the section  10  can comprise separate anchoring bodies such as anchors in the anchoring ropes that are operated by a windlass. 
     The inventive construction is now operative and the first transport ship  60  ( FIG. 4 ) can dock at the outermost construction which is section  10 . The ship  60  can use its own stern and aft anchors. In addition it can use dynamic and automatic positioning (GPS) if this is required and available. It the ship is a so called Ro-Ro ship, it will be able to be unloaded in a very short time and tanks can, for example, be driven directly onto land over the three sections  10 ,  20  and  30 . 
     The construction according to the invention can, because of its great mobility and speed, also be used in a series of civilian operations and commercial applications related to different offshore and installation activities.