A METHOD AND DEVICE FOR SECURING CLOSED DECKS AND CARGO ON SHIPS RESPECTIVELY

Abstract: In order to secure closed decks and cargo respectively on board a ship (1), e.g. a deck (2) for vehicles or cargo in a hold, a device is employed which consists of extendable, gas-fillable, highly elastic bags (4) which are attached on a roller device in the ceiling of the deck space. The elastic bags are provided at distances from one another corresponding to the breadth of the normal cargo for the ship, especially vehicles (3). After the cargo (3) has been positioned in the areas between the bags (4), the latter are pulled down and fastened to suitable attachment means in the floor of the deck. The bags (4) are then inflated to a low gauge pressure, thereby expanding and enveloping the cargo (3) from the side and at least partially over the cargo (3). They will thereby fill a substantial part of the open airspace on the deck.

Description: A method and device for securing closed decks and cargo on ships respectively The invention concerns a method and a device for securing closed decks and cargo on ships respectively, e.g. decks for vehicles or cargo in holds. From the applicant's Norwegian patent application 942529 a system is known for securing cargo, which consists of a highly elastic rubber bag/rubber membrane which in an inflated state secures the cargo in a hold, the cargo being fixed in position when "free" airspace in the cargo hold is replaced by the highly-elastic, air-filled rubber bag. In the case of this device according to claim 942529 a rubber bag is used which is mounted in advance in the ceiling of the cargo hold and which is filled with air from an air pumping set and the air pressure is adjusted and controlled, in order to ensure that the rubber bag is only inflated to a pressure which prevents the cargo from shifting. A rubber bag is used with a very high degree of elasticity of elongation, a minimum of 500%. This cargo securing system can be used both in cars, boats, aircraft and on the railway. In the case of transport of cargo, e.g. vehicles on ships, where the vehicles or the cargo are placed on large open decks and also when positioning large objects, including vehicles in large cargo holds, however, in addition to simply securing the load, there has been a requirement for a more substantial division of the cargo surface or the deck, thus enabling not only the cargo to be secured but also providing security for the entire ship by dividing the large spaces and surfaces into smaller sections. The effect of a sectional partitioning or division into compartments of this kind will mean that the penetration of water both into the cargo hold and on to a cargo deck will be restricted to limited areas and also enable the movement of large amounts of water athwartships in heavy seas to be avoided. Thus it is an object of the present invention to provide a method and a device for securing closed decks and cargo on ships respectively by means of such a sectional partitioning of large, open spaces. This object is achieved with a method and a device which are characterized by the features in the patent claims. In the invention a cargo hold or deck which is open during loading and unloading can, after the cargo has been placed in position, be divided up in a very simple fashion into smaller units, while at the same time the cargo is secured in a simple and reliable manner. By means of the invention the open space on the deck or in the hold is also filled, a minimum of space thereby being available for penetration of water in the event of an accident and in addition to the fact that the amount is reduced, this water will have only limited capability of movement, thereby substantially improving the security of the ship. In addition to this the invention offers a number of further advantages. The inflated bags according to the invention will give the ship an extra buoyancy in the event of an accident, thus enabling the ship to be kept afloat longer than normal in an emergency situation and even possibly preventing it from sinking. The opportunities for summoning help will therefore be much greater. According to a feature of the invention the filled gas bags can also be filled with a fire-retardant gas. thus automatically extinguishing any small fires which may break out. A further advantage which is obtained by means of the invention is that the cargo is automatically secured without the necessity of employing traditional securing equipment such as chains and straps. This means a substantial rationalization in connection with loading and unloading, while at the same time the cargo is carefully secured with an evenly distributed securing effect over the entire surface of the cargo. The cargo can be automatical 1}' tightened up during transport by adjusting the securing pressure. The cargo securing can also be constantly monitored by means of sensors. A further advantage which is obtained by means of the invention is that in cases where the hold or deck is not full, the vehicles or the cargo can be located in the most favourable positions on the ship, since by inflating the bags the cargo can be secured and kept in the desired position on the cargo surface. The device according to the invention can be built into existing ships and car ferries without the need for comprehensive mechanical conversions which alter the vessel's mechanical characteristics. The device is very easy to use. and will it not lead to a reduction in the capacity on board the ship. By placing the bags in a grid pattern, the space can be divided and securing can be obtained against the outer edges of the ship, e.g. against the vehicle doors at the ends of the ship, which provides an additional security. The attachment means in the deck's driving plate can be advantageously located in such a manner that they establish driving lanes for the vehicles on a car deck and thereby also facilitate the correct positioning of the vehicles. The invention will now be described in more detail by means of an embodiment in the form of a vehicle deck on a car ferry, and the drawing in which: Fig. 1 is a plan view of the car deck on a ferry, illustrating the device according to the invention, fig. 2 is a sectional view of a car ferry with two ferry decks, fig. 3 is a detail view of the device according to the invention in an intermediate position when a car deck is divided up into compartments, fig. 4 is the car deck in fig. 3 in a secured position, fig. 5 is a perspective view of a bag according to the invention in an extended position and attached at its lower edge, and fig. 6 is a perspective partial view of the rolling up system for the bag for the device according to the invention. Even though the drawing illustrates the use of the invention on a car deck in connection with the securing of the vehicle, it is obvious that the invention can be used in a far wider context than this, and any type of cargo can be secured, not only on a car deck, but also in cargo holds, etc. Fig. 1 of the drawing illustrates a car deck on a ship or ferry 1 , where the deck is denoted by 2. On this deck vehicles or cars, which are denoted by 3, are lined up behind one another in the conventional manner. Between these rows of cars, in the ceiling of the deck space there are suspended extendable, gas-filled, highly elastic bags which are suspended in the areas which are denoted by 4. For additional securing and partitioning of the space, corresponding elastic bags can also be provided athwartships, e.g. in the locations denoted by 5. By providing extendable bags of this kind in the two ends of the ship, extra securing of the vehicle doors etc. can be obtained. Fig. 2 illustrates a section through such a car deck with the device according to the invention in a secured state. Figs. 3 and 4 illustrate purely schematically the positioning of the elastic bags between the vehicles on the deck. The bags 4 are illustrated here in an extended position, where they are fastened by means of attachment means 7 to the floor of the deck between the vehicles. In this position a longitudinal sectional division of the car deck has been achieved, which will prevent any water which has penetrated into the ship from washing back and forward between the ship's transverse sides. Fig. 4 illustrates the device according to the invention in the securing position, the elastic bags being inflated and thereby securing the cargo, i.e. the vehicles and also filling the space between the vehicles above and at the side. This fϊl- ling operation is performed in the lateral direction of the vehicles, thus hold- ing them securely against one another, but as the expansion of the bags proceeds the vehicle will also be secured from the top and thereby be held secure in a cushioned fashion. Only the space 8 under the vehicles will be free. Figs. 5 and 6 illustrate the suspension and the attachment of the bags 4. In their extended position the bags act as a kind of curtain. Their lower edge is designed with a weight load or beam arrangement 9 which holds the bag taut like a curtain in the longitudinal direction, in the example shown pulled down in such a manner that the beam 9 is located in a recess 13 in the floor of the deck. This is not an absolute requirement, since the beam can also be made to abut against the actual deck floor 6. On each side of this area 13 there are provided rotatable plate elements with rounded ends which can be rotated towards each other by means of suitable drive means and thereby grip the curtains or the top of the beam 9 and hold it in place. Thus in this position there is provided a curtain or wall secured above and below between each row of cars, which will prevent movement, e.g. of water in the ship's transverse direction. The mechanism for rolling up the bag or the curtain 4 is illustrated in fig. 6. In the ceiling of the deck or the cargo hold, e.g., there is attached with a bracket 10 a rotatable roller 11, which is motor-driven, thus enabling the curtain 4 to be rolled up or pulled down according to the direction of rotation. When it is rolled down the beam 9 will ensure additional traction in a downward direction. During loading and unloading of the ship the bag 4 will be in a rolled-up state, e.g. as illustrated in fig. 4. For inflation of the bag the roller 1 1 can be designed with one or more rows of holes or slots 12, as illustrated in the lower part of fig. 6 and also in fig. 5. The ends of the roller are thereby sealed and it is in communication with an air intake from a compressor or another air source which can blow in air which fills the bags through holes 12. causing the bags to expand and envelop the vehicles as illustrated in fig. 4. During retraction air is extracted through the same system, causing the bags to contract into the form of curtains, whereupon they can be rolled up. It should be pointed out that it is an essential feature that the bags have a very high degree of elasticity, thus allowing them to be expanded as much as 500%. Thus the bag will not slide against the surfaces of the cars, but expand around these surfaces, thus preventing any sliding or tearing effect against the surfaces. To summarize, the mode of operation of the invention can be said to be as follows: 1. In the cargo hold several airtight bags 4 of a highly elastic material are mounted. These are mounted halfway between the rows of cars. 2. The bags 4 are mounted on a hollow tube 1 1 which can be rolled up when vehicles are driving ashore and on board, see fig. 6. 3. After the cars have driven aboard, the bag 4 is rolled out and clamped mechanically to the bottom by means of the devices 7 and 9. The bag is then inflated with air or gas via the hollow tube 1 1. 4. The bag will thereby gradually envelop all the cargo and secure it as the pressure rises in the bag 4. A pressure regulating valve is released when the correct pressure is reached. 5. The cargo will be enclosed by an envelope which keeps the air confined. There is a pressure difference between the inside and the outside of the bag which secures the cargo in a careful manner. The pressure is evenly distributed against all surfaces of the cargo. It will be possible to regulate the strength with which the cargo is secured by means of the pressure. 6. Watertight compartments will be established in the longitudinal direction as a result of the securing of the bags at the bottom and the top. By means of the invention it will be possible to have full control over the security status on the vehicle deck or in the cargo hold by monitoring the pressure in the respective bags. Moreover, the ship has been provided with an extra buoyancy force by means of the bags and this will give additional security in the event of water penetrating into the deck or the hold. At the same time the cargo is secured without the use of securing straps etc., thus enabling cargo to be secured more easily and rapidly than before. The invention provides a very flexible solution, since the system can be built into existing ferries without comprehensive mechanical conversion which could result in a change in the vessel's mechanical characteristics. The securing method is also extremely flexible and can also be employed in the case of only partially filled decks, since, at any rate in rough weather, the remaining empty spaces can be completely filled by means of the air bags. Many modifications will be possible within the scope of the invention. Furthermore, it will be possible to monitor the system by means of sensors, and pressure regulators which will ensure that the situation on the vehicle deck remains constant.

Claims: PATENT CLAIMS 1. A method for securing closed decks and cargo on ships respectively, e.g. decks for vehicles or cargo in holds, characterized in that in the ceiling of the deck or the cargo hold, preferably in the ship's longitudinal direction, there are suspended extendable, gas-fillable highly elastic bags, which are located at distances from one another corresponding to the breadth of the normal cargo for the ship, especially vehicles, that after the cargo, especially vehicles, has been positioned in the areas between the bags, these bags are pulled down and fastened to suitable attachment means in the deck, and that the bags are then inflated to a low gauge pressure, thus causing them to expand and envelop the cargo from the side and at least partially also over the cargo, thereby filling a substantial part of the open airspace on the deck. 2. A method according to claim 1 , characterized in that the bags are inflated to a pressure corresponding to a maximum of 500 mm water column. 3. A method according to claim 1, characterized in that the bags are inflated with a fire-retardant gas. 4. A method according to claim 1 , characterized in that a plurality of bags are provided behind one another in the longitudinal direction of the ship, that when required, e.g. in the case of long decks, bags are also provided athwartships, in the gaps between the longitudinal bags, and that transverse bags may be provided at the ends in front of the vehicle doors. 5. A device for securing closed decks and cargo on ships respectively, e.g. decks for vehicles or cargo in holds, characterized in that in the ceiling of the deck, in the longitudinal direction thereof, there are provided suspension means for a contracted bag of a highly elastic material, with driving means for extension/retraction of the bag to/from a position in which it extends down to the actual deck, that immediately below the suspension means attachment means for the bag are provided in the deck, that the bag is of a material, preferably a rubber or a plastic which is capable of expanding in the order of 500% when filled with a gas, that equipment is provided for filling/evacuating the bag with gas, which equipment comprises control members for adjusting and controlling the gas pressure. 6. A device according to claim 5, characterized in that the bags are divided into separate individual sections in the deck's longitudinal direction. 7. A device according to claim 6. characterized in that at suitable distances between the bag sections there are provided corresponding extendable bag devices in the transverse direction. especially at the end areas of the deck. 8. A device according to claim 5. characterized in that the extension/retraction means are composed of rotatable, driven rollers or the like, and that the free end of the bag is equipped with a weight load in the form of a longitudinal bead or beam- shaped stiffener. 9. A device according to claim 5, characterized in that the attachment means for the bag in the deck are composed of rotatable clamp beams to cooperate with a bead or stiffener along the end edge of the bag from both sides, and that there is preferably provided a recess in the deck to control and secure the end edge of the bag.

Inventors: FJELD ASLAK, FJELD, ASLAK
Applicants: FJELD ASLAK, FJELD, ASLAK
Application year: 1995
Main classification: B63B25
IPC codes: B60P7, B63B25, B63B43