A floating device made of soft material, mounted on a ship, for launching and recovering a watercraft.

Abstract

The invention relates to a floating device (1) made of soft material intended to be mounted on a vessel (3) for launching and recovering a watercraft (2), such as an inflatable boat. The floating device (1) comprises a lower face (11) in contact with the water, an upper face (10) opposite the lower face (11) on which the watercraft (2) to be launched or recovered is intended to move, two opposing lateral edges (14, 15) connecting the upper face (10) and the lower face (11), a front end intended to be connected to the vessel (3), and a free rear end having a notch (17) for positioning or securing the watercraft (2) relative to the floating device (1). The floating device (1) further comprises, on its upper face (10), a groove (18) for guiding and stabilizing the watercraft (2) on the floating device (1). FIG. 1

Description

Title of the invention: Floating device made of soft material mounted on a ship for launching and recovering a watercraft Scope of the invention

[0001] The present invention is in the naval field and relates more specifically to a device for launching and recovering a watercraft (for example a semi-rigid hull boat) from a ship capable, on the one hand, of extracting the watercraft from the water to a rear ramp of the ship, and on the other hand of lowering the watercraft from the rear ramp of the ship to the sea. State of the art

[0002] Launching, and especially recovering, a watercraft, such as an inflatable boat, from a ship is a particularly delicate operation due to the relative movements of the craft with respect to the ship, which is itself moving. The complexity of these operations is further accentuated when there is a significant size difference between the craft and the ship. These operations are usually carried out using a lifting device equipped with a boom or arm that supports a cable ending in a hook, the assembly serving to lower the craft from the ship to the sea or to lift the craft and place it on the ship.

[0003] Ships equipped with ramps allowing boats to beach themselves against the stern are also known. These operations generally require human intervention, which is made more difficult and dangerous in rough seas. A drawback of these ramps is that the boat can strike the ship's hull, especially in rough seas. In this case, there is a risk of damage to the boat and endangers the safety of those in the boat, as well as those on the ship involved in the maneuver.

[0004] To remedy these drawbacks, it has been proposed to configure the ramp so that its lower end is located below the surface of the water so that the vessel located on the sea comes into contact with the inclined surface of the ramp and not with its submerged lower end.

[0005] This solution is generally not suitable for use in rough seas and does not prevent violent impacts between the boat and the inclined surface. Furthermore, such a ramp does not prevent lateral movement of the boat due to water movement, which can also damage the ramp and / or the boat. In addition, access for maintenance of such an inclined ramp proves difficult.

[0006] Current solutions are therefore not entirely satisfactory and there is a need for a vessel equipped with an installation which allows the rapid launching and recovery of watercraft in the safest possible manner, regardless of the state of the sea, and which is compatible with a wide variety of watercraft to be recovered or launched. Description of the invention

[0007] To address these difficulties, a floating device made of soft material is proposed, intended to be mounted on a ship (also referred to hereafter as a "mother ship" or "carrier ship") for launching and recovering a watercraft (for example, an inflatable boat), comprising a lower face in contact with the water, an upper face opposite the lower face on which the watercraft to be launched or recovered is intended to move (or progress), two opposite lateral edges connecting the upper and lower faces, a front end intended to be connected to the ship and a free rear end having a notch for positioning or securing the watercraft relative to the floating device, the floating device further having on its upper face a groove for guiding and stabilizing the watercraft on the floating device.

[0008] The main advantage of this invention is to cushion the shocks during the launching and recovery of the watercraft, such a floating device made of soft material ensuring a transition of the watercraft tolerant to relative movements and shocks.

[0009] The front end of this floating device has a guide and stabilizing groove for the watercraft on the device, allowing the watercraft to slide along the upper surface of the device. The free rear end of this floating device has a notch for positioning the bow of a watercraft relative to the floating device during recovery and for securing the rear of the watercraft during its launch.

[0010] The floating device is therefore configured to pre-position the watercraft in line with the ship's rear ramp, guide it along this axis and prevent it from tipping to one side or the other (i.e. transversely) when it is in the recovery or launching phase of the watercraft.

[0011] The floating device allows for the rapid and therefore safe launching and retrieval of a watercraft without damaging it. The risk of collision between the vessel and the watercraft during these maneuvers is reduced, and the safety of those involved is preserved.

[0012] The floating device also helps to cushion the shocks due to water movements and to avoid direct contact between the watercraft and the rear ramp of the ship.

[0013] Its soft and flexible structure provides flexibility. By soft material, we mean a material that can be elastically deformed.

[0014] The floating device can be replaced by another floating device and optimized according to the desired buoyancy.

[0015] The simple and flexible solution of the invention is very different from the lifting gantries of the prior art which use multiple mechanical parts (boom, rails, motor,...), and which are of rigid structure.

[0016] The invention finds a particular application in the launching and recovery of semi-rigid boats, called RHIB for "rigid-hulled inflatable boat" in English.

[0017] Without this list being exhaustive, the watercraft may be a surface vessel or an underwater vessel (submersible). Similarly, it may be a rigid inflatable boat or an inflatable boat propelled by oars or a motor (called a secondary vessel) capable of carrying / transporting one or more persons and / or cargo. It may also be autonomous or remotely operated vessels.

[0018] Other advantages of the floating device are listed below: - simplification of the maneuver and optimization of the safety of operators and passengers during the launching and recovery of the watercraft; - limitation of relative movements during maneuvers, increase of contact surfaces to distribute the forces; - adaptability and versatility of the solution: interchangeable buffer piece, adaptable to different sizes and different types of nautical equipment, independently of the carrier boat; - safe embarkation and disembarkation of passengers; - usable regardless of sea conditions; - speed of operations and optimized safety: recovery time less than 2 minutes and drop time less than 30 seconds; - reduction in the number of people required for boat maneuvers (three maximum); - improved durability and easy maintenance (simple assembly / disassembly afloat without requiring tools or dedicated infrastructure); - ease of replacement in case of wear or deterioration; - the floating device forming the interface between the watercraft and the ramp The rear of the ship does not require any structural modification to the ship.

[0019] The installation, including in particular the floating device and the ship's rear ramp, has in particular the following characteristics: • The guide and stabilizing groove extends across the upper face of the floating device from the bottom of the notch located at the rear end to the front end of the floating device. • The floating device is composed of cross-linked foam. • at least part of the surface of the guide and stabilizing groove is covered with at least one layer of high-density polyethylene (HDPE) to ensure the sliding of the watercraft on the floating device. • the front end of the floating device has between its opposite lateral edges an internal bore for the passage of a flexible axis of rotation of the floating device relative to the ship, the axis of rotation being substantially parallel to the surface of the water when said floating device is fixed to said ship. • the height of the floating device between the upper and lower faces at the front end is greater than the height of the device at the rear end so that the upper face has a slope towards the rear of the floating device. • said rear ramp of the ship comprises a metal frame, covered with a rubber complex and at least one layer of coating in Polytetrafluoroethylene (PTFE). • The flexible axis of rotation of the floating device relative to the ship consists of a metal or synthetic material cable stretched between two turnbuckles fixed to the ship. • the rear ramp of the ship has rollers on its lateral edges to guide the watercraft to be put into the water or retrieved. • The installation includes a winching system consisting of a winch for winding a retaining cable for the watercraft as it progresses on the floating device and the rear ramp of the ship. • the buoyancy of the floating device is chosen such that when the watercraft is located on the floating device, the slope of the upper face of the floating device is equal to the slope of the rear ramp of the ship.

[0020] The invention is thus intended for a vessel equipped with a launching and recovery installation for a watercraft comprising a floating device as described above and a ramp located at the rear of the vessel and having lateral edges inclined outwards, said ramp being configured to cooperate with the floating device to launch or recover a watercraft. List of Figures

[0021] The drawings in the appendices provide a non-exhaustive illustration of the proposed technique and its various advantages:

[0022] [Fig. 1] is a top view of the floating device according to one embodiment of the invention;

[0023] [Fig.2] is a perspective view of the floating device according to [Fig.1];

[0024] [Fig.3] is a side view of the floating device according to [Fig.1]

[0025] [Fig.4] is a top view of the rear part of a ship equipped with an installation launching and recovery of a nautical craft;

[0026] [Fig.5] illustrates this rear part seen from the side and shows a nautical craft at sea at proximity of the floating device (left) and in storage position on the ship's rear ramp (right);

[0027] [Fig.6] illustrates an example of a ship's rear ramp equipped with a shipboard installation launching and recovery of a nautical craft. Detailed description of the invention

[0028] A vessel equipped with a launching and recovery system for watercraft, comprising a floating device made of soft material according to an embodiment of the invention, is described below. As illustrated in Figures 4 and 5, the mothership has a stern ramp equipped with such a floating device, which is mounted on a pivot axis for launching and recovering watercraft, which in this example is a RHIB-type craft for rescue operations, among other things. The system is configured, on the one hand, to lower such a craft to the surface of the sea from the vessel and, on the other hand, to extract such a craft from the sea and then hoist it onto the vessel.

[0029] The installation for launching and recovering watercraft consists of the following elements: - a structural rear ramp integrated into the shape of the mothership's hull; - a floating device or float forming a soft interface between the craft and the mother ship, and - an integrated winching system on the mothership. Floating device or soft material float

[0030] An example of a floating device according to the invention is shown in Figures 1 to 3. This floating device 1 is in the form of a soft material plate having a substantially flat lower surface 11 intended to come into contact with the water and an inclined or sloping upper surface 10, two straight lateral edges 14, 15, a straight front edge 13, and a rear edge 12. The front end of the floating device 1 is intended to be connected to the vessel 3, and the rear end is free. The rear edge 12 has a notch 17 for positioning or securing a vessel 2 relative to the floating device 1, having a "V" shape with its sides converging towards the center of the plate. This notch 17 is symmetrical by relative to the longitudinal axis of the plate, which extends between the front edge 13 and the rear edge 12. The notch 17 extends over a portion of the plate's width, defined between the two opposite lateral edges 14 and 15. The depth of the notch 17 is equal to one-quarter of the plate's length. The plate's thickness, defined between the upper surface 10 and the lower surface 11, is greater at the front end than at the rear end.

[0031] In addition to this notch 17 for positioning or securing a boat in relation to the floating device 1, the upper surface 10 of the floating device 1 has a groove 18 for guiding and stabilizing the boat 2 on the floating device 1.

[0032] This axial groove 18 extends from the bottom of the notch 17 to the forward end of the floating device 1. This groove 18 is symmetrical with respect to the longitudinal axis of the plate and extends over part of the plate's width. It is flared in shape, its width at the bottom of the notch 17 being greater than its width at the forward end of the floating device 1. Its length is approximately three-quarters of the plate's length. It has a first portion extending from the bottom of the notch 17 with a slope (or angle of inclination) corresponding to that of the ship's stern ramp when the watercraft is on the floating device, and a second portion with a gentler slope located at the front of the plate ([Fig. 2]).

[0033] The floating device 1 can be solid or hollow.

[0034] The floating device 1 may be composed of cross-linked foam, made of polyethylene by example or any other suitable material, on which a coating can be applied, for example polyurethane.

[0035] The surface of the axial groove 18 is covered with at least one layer of high-density polyethylene (HDPE) coating to ensure the sliding of the boat 2 on the floating device 1. The V-shaped notch 17 allows: - to guide the bow of the boat 2 towards the axial groove 18 when the boat 2 is recovered for storage on the ship 3 (it is therefore a docking notch when the boat 2 is recovered), and - to wedge the rear of the boat 2 during the transitional phases of its recovery or launching.

[0036] The groove 18 with a "V" cross-section helps to keep the boat 2 on the axis and to limit its list.

[0037] More generally, the shape of the floating device 1 is designed so that: - the floating device acts as an extension of the rear ramp 31 of the ship 3, - the hull of boat 2 reaches the correct height in the rear ramp 31 of ship 3 (i.e., neither too high nor too low) and do not come to hit the stern of the mother ship 3.

[0038] The slope of the floating device 1 ensures the launching of the boat 2 by gravity and is particularly suitable for semi-rigid boats.

[0039] The buoyancy of the floating device 1 is chosen such that when the watercraft is located on

[0040] the floating device, the slope of the upper face 10 of the floating device 1 (and more specifically the

[0041] The slope of groove 18) is equal to the slope of the ship's rear ramp (the watercraft must not

[0042] be located too high or too low in relation to the rear ramp).

[0043] As can be seen in [Fig. 3], the front end of the floating device 1 having between its opposite lateral edges 14, 15 an internal bore 16 through for the passage of a flexible axis 19 of rotation of the floating device 1 relative to the ship 3, the axis of rotation being substantially parallel to the surface of the water when the floating device 1 is connected to the ship 3.

[0044] The flexible shaft 19 which passes through the internal bore 16 is made of a metal cable or of synthetic material.

[0045] The tension of this cable is adjusted using two turnbuckles 32 located on each side of the floating device 1 and fixed to the structure of the mother ship 3.

[0046] The axis of rotation or pivoting of the floating device 1 formed by the flexible axis 19 is therefore offset from the stern of the ship 3 and distant from the latter so that there is no contact between the stern of the ship 3 and the floating device 1.

[0047] The tension of the flexible shaft 19 is chosen to retain the floating device 1 and absorb axial forces (shocks) without transmitting them to the structure of the mother ship 3. Using a flexible axis rather than a rigid axis allows for several degrees of freedom and cushions the shocks when boat 2 arrives on the floating device 1.

[0048] The absorption of shocks and associated energy is based on three principles: • Archimedes' principle, due to the sinking of the floating device 1 under the effect of the boat 2 (when the float is submerged in the water, a damping effect is obtained in reaction due to the Archimedes' principle); • the composition of the floating device 1: made of cross-linked foam coated, for example, with polyurethane or equivalent, and which may be reinforced with three woven layers, and • the pivot connection by a flexible cable (synthetic or metallic)

[0049] From its lowered position, the floating device 1 can be raised (into the position of

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058] (storage or raised position) manually or with a motor. Indeed, it is not advisable to leave the floating device 1 trailing behind the carrier vessel 3 during operation. A system (not shown) on the stern of vessel 3 allows the floating device 1 to be raised or lowered. These operations are facilitated by the fact that the floating device 1 is relatively compact and lightweight, and therefore relatively easy to handle. In addition to the floating soft material device that is the subject of this invention, the ship's watercraft launching and recovery installation includes a rear ramp and a winching system, which are detailed below. Ship's rear ramp The rear ramp 31 of ship 3 is shown in [Fig.6], and is also visible in figures 4 and 5. This 31 rear ramp is made of aluminium and is directly integrated into the hull of the 3 mother ship. The slope of this rear ramp 31 has been designed to allow launching by gravity without external effort. This slope is between 10° and 14°. The slope of the rear ramp 31 is in continuity with that of the floating device 1 to allow the boat 2 to slide from the rear ramp 31 to the floating device 1 or vice versa. Several accessories are arranged on this rear ramp 3: - a so-called "sliding" interface 311 having a flat central part and two opposing lateral edges sloping or inclined outwards, and - guide rollers 312 (four in this example) which are integrated on each side of the sliding interface 311. They allow the boat 2 to be guided during the raising or launching phases and prevent it from tipping to one side or the other. The 311 sliding interface consists of four plates inserted into U-shaped aluminum profiles. Each plate comprises: - a rubber or polymer core - a PTFE coating on each face The role of this 311 sliding interface is: - to absorb any potential shocks between boat 2 and the aluminum structure of the mother ship 3, and - to allow the sliding of boat 2 and its launching by gravity. Winching system The 32' winching system includes a cable wound around the drum of a winch. Lashing points are provided on the lower part of the hull of the watercraft. or craft 2 which is towed from the front. The winching system therefore pulls (or holds during launching) the watercraft from below during the lifting onto the vessel 3. How it works

[0059] The operation of the installation for launching and recovering a watercraft is described below using the numerical references of figures 4 and 5.

[0060] During a recovery step, the watercraft to be recovered 2 is initially located in the water as illustrated in the top view of [Fig.4], near the floating device 1 which is connected to the vessel 3 by a flexible pivot axis as described previously.

[0061] The watercraft 2 is advanced on the V-groove 18 of the floating device 1 by being guided by the V-notch 17. The notch 17 is intended to guide the movement of the watercraft 2 in the axis of the floating device 1 and the rear ramp 31 of the mother ship 3.

[0062] When the watercraft reaches the floating device 1, the latter pivots around its axis of rotation and sinks into the water under the weight of the watercraft 2. This helps to absorb the shock (by displacing water). The angle formed by the floating device 1 with the watercraft 2 corresponds to the angle of the rear ramp 31. Once the watercraft 2 is in contact with the floating device 1, the latter acts as an extension or continuation of the rear ramp 31 to allow the watercraft 2 to slide from the rear ramp 31 to the floating device 1 or vice versa.

[0063] One of the advantages of the invention is to avoid collisions in the event that the watercraft 2 arrives at speed by absorbing the impact and allowing the watercraft 2 to position itself on the floating device 1 in order to stabilize its movements so that the operator can retrieve and attach the towline. The winching system 32' then allows the watercraft 2 to be raised onto the stern ramp 31 of the vessel 3.

[0064] The stern ramp 31 of the vessel 3 and the floating device 1 are configured to guide the watercraft 2 along a straight trajectory, thus preventing it from moving laterally. In this way, the launching and recovery of the watercraft can be carried out while the vessel is moving. The watercraft, towed by the vessel, naturally positions itself in line with the vessel's direction of travel.

[0065] The floating device 1 being made of soft material, it ensures a transition of the watercraft tolerant to relative movements and shocks, and allows: - to cushion the shock on arrival of the boat or watercraft; - to guide the boat along the axis of the rear ramp, and - to stabilize the boat while the operator retrieves the towline.

[0066] A launching and recovery system for a watercraft, incorporating a floating device according to the invention, thus makes it possible to grasp such a watercraft without damaging it. The risks of collision between the vessel and the floating watercraft are also reduced.

Claims

Demands

1. A floating device (1) made of soft material intended to be mounted on a ship (3) to facilitate the transition of a watercraft (2) between said ship (3) and the water during the launching and recovery of said watercraft (2), such as an inflatable boat, the floating device (1) comprising a lower face (11) in contact with the water, an upper face (10) opposite the lower face (11) on which the watercraft (2) to be launched or recovered is intended to move, two opposing lateral edges (14, 15) connecting the upper face (10) and the lower face (11), a front end intended to be connected to the ship (3) and a free rear end having a notch (17) for positioning or securing the watercraft (2) relative to the floating device (1),the floating device (1) further having on its upper face (10) a groove (18) for guiding and stabilizing the watercraft (2) on the floating device (1) in which the guiding and stabilizing groove (18) extends on the upper face (10) of the floating device (1) from the bottom of the notch (17) located at the rear end to the front end of the floating device (1).

2. Floating device (1) according to claim 1, which is composed of cross-linked foam.

3. Floating device (1) according to claim 1 or 2, at least a portion of the surface of the guide and stabilizing groove (18) being covered with at least one layer of high-density polyethylene (HDPE) to ensure the sliding of the watercraft (2) on the floating device (1).

4. Floating device (1) according to any one of the preceding claims, the front end of the floating device (1) having between its opposite lateral edges an internal bore (16) for the passage of a flexible axis (19) of rotation of the floating device (11) relative to the ship (3), the axis of rotation being substantially parallel to the surface of the water when said floating device (1) is fixed to said ship (3).

5. Floating device (1) according to any one of the preceding claims, the height of the floating device (1) between the upper and lower faces at the front end being greater than the height of the device at the rear end so that the upper face (10) has a slope towards the rear of the floating device (1).

6. Vessel (3) equipped with a launching and recovery facility of a watercraft comprising a floating device (1) according to any one of claims 1 to 5 and a ramp (31) located at the rear of the vessel (3) and having lateral edges inclined outwards, said ramp (31) being configured to cooperate with the floating device (1) for launching or recovering a watercraft (2).

7. Vessel (3) according to claim 6, said stern ramp (31) of the vessel comprising a metal frame covered with at least one layer of Polytetrafluoroethylene (PTFE) coating.

8. Vessel (3) according to claim 6 or 7 and claim 4, the flexible axis (19) of rotation of the floating device (1) relative to the vessel (3) being composed of a cable made of metal or synthetic material stretched between two turnbuckles (32) fixed on the vessel (3).

9. Vessel (3) according to any one of claims 6 to 8, the aft ramp (31) of the vessel having on its lateral edges guide rollers (312) for the watercraft (2) to be launched or recovered.

10. Vessel (3) according to any one of claims 6 to 9, the installation comprising a winching system (32') including a winch for winding a retaining cable of the watercraft (2) during its progress on the floating device (1) and the rear ramp (31) of the vessel (3).

11. Vessel (3) according to any one of claims 6 to 10, the buoyancy of the floating device being chosen such that when the watercraft (2) is located on the floating device (1), the slope of the upper face (10) of the floating device (1) is equal to the slope of the rear ramp (31) of the vessel (3).