EP0169781B1 - Device for taking watercraft aboard ships - Google Patents

Description

The invention relates to devices for embarking boats on board ships and for putting them in the water from these ships.

It relates more specifically to those of these boarding devices, which include a ramp coupled to the rear of the ship so as to pivot about a transverse horizontal axis linked to the ship, a ramp capable of supporting boats between the water and a reception area provided on board the ship, as described in document GB-A-185221.

• - la résistance de traînée opposée à l'avancement du navire lorsque la portion arrière du panneau est immergée dans l'eau est relativement élevée, de sorte que les opérations d'embarquement et de débarquement ne peuvent être effectuées que lorsque le navire est à l'arrêt ou progresse à petite vitesse,
• - la forme convexe des faces inférieures des coques d'embarcation se prête mal au support et au guidage de ces coques par des panneaux plans et pleins et lesdites faces sont détériorées lors de leurs glissements sur de tels panneaux,
• - le support en question requiert fréquemment un escamotage préalable vers le haut des hélices et de leur moteur d'entraînement.

In the known embodiments of these boarding devices, the ramp is constituted by a flat and solid panel, which has a certain number of drawbacks and in particular the following:

• - the drag resistance opposed to the advance of the ship when the rear portion of the panel is immersed in water is relatively high, so that boarding and disembarking operations can only be carried out when the ship is at '' stops or progresses at low speed,
• the convex shape of the lower faces of the boat hulls lends itself poorly to the support and guiding of these hulls by flat and solid panels and said faces are deteriorated when they slide over such panels,
• - the support in question frequently requires prior retraction of the propellers and their drive motor upwards.

The object of the invention is, above all, to remedy these various drawbacks by making it possible in particular to ensure the embarkations considered even when the ship is moving at a relatively high speed which can reach or even exceed 20 knots, as is required for the embarkation of certain canoes and speedboats sailing in a hostile environment.

To this end, the boarding devices according to the invention are essentially characterized in that the ramp is formed by a sheet of cables stretched over a V-shaped cradle itself composed of longitudinal members extending along a widely open V and of horizontal sleepers bracing these members, the constituent elements of this cradle capable of being immersed all having a small cross section so that the drag resistance generated by their immersion is very low.

• - le berceau est décomposé en deux demi-berceaux sensiblement identiques rendus solidaires l'un de l'autre par entretoisement de leurs portions les plus éloignées de la nappe de câbles,
• - les deux demi-nappes de câbles portées respectivement par les deux demi-berceaux ci-dessus sont composées chacune de câbles parallèles et les directions des câbles de ces deux nappes convergent vers l'avant du navire,
• - des moyens sont prévus pour exploiter automatiquement à des fins de commande du relevage de la rampe l'impact de l'avant de chaque embarcation à embarquer contre une butée en regard portée par le navire.

In preferred embodiments, use is also made of one and / or the other of the following arrangements:

• the cradle is broken down into two substantially identical half-cradles made integral with one another by bracing their portions furthest from the cable ply,
• the two half-plies of cables carried respectively by the two half-cradles above are each composed of parallel cables and the directions of the cables of these two plies converge towards the bow of the ship,
• - Means are provided for automatically exploiting, for the purpose of controlling the lifting of the ramp, the impact of the bow of each boat to be loaded against a facing abutment carried by the ship.

The invention includes, apart from these main provisions, certain other provisions which are preferably used at the same time and which will be more explicitly discussed below.

• La figure 1, de ces dessins, montre en vue perspective schématique un dispositif d'embarquement établi selon l'invention.
• Les figures 2 et 3 montrent respectivement en coupe verticale selon 11-11, figure 3, et en plan l'élément essentiel de ce dispositif d'embarquement.

In what follows, a preferred embodiment of the invention will be described with reference to the accompanying drawings in a manner which is of course not limiting.

• Figure 1 of these drawings shows in schematic perspective view a boarding device established according to the invention.
• Figures 2 and 3 show respectively in vertical section along 11-11, Figure 3, and in plan the essential element of this boarding device.

It is proposed to embark on board a ship 1 during movement at least one boat 2 such as a motor boat.

A reception garage 3 is provided on the ship for the boat, a garage open aft of the ship, and the floor 4 of this garage is extended aft by a towed ramp 5 pivotally mounted around a horizontal axis. transverse X extending substantially in the plane of the transom of the ship, ramp whose rear end floats on water or is immersed in water over a shallow depth.

This ramp 5 is arranged so as to support the boats between the water and the garage and to guide the progression of these boats by sliding between these two zones without injuring their hulls.

To this end, said ramp 5 is constituted by a sheet of cables 6 stretched over a cradle itself composed of longitudinal members 7 braced by horizontal crosspieces 8.

The portions of these components 7 and 8, which are immersed in water when the ramp 5 is in its lowered and towed operating position, each have a small and profiled cross section so as to generate a negligible drag resistance with respect to the energy required to propel the ship.

This is how each member 7 is given the flat shape of a boomerang or lever bent along an enlarged V at its elbow.

As for the horizontal crosspieces 8, these essentially constitute those capable of being submerged by two wings or "planes" of lift, one before 8, located at the elbows of the members 7 and the other rear 8 ₂ located near the rear end of each member.

The shapes, dimensions and orientations of the two wings 81, 8 ₂ are chosen so that the result of the stresses exerted by these two wings on the cradle when the ship is moving stabilizes the inclination of this cradle on the horizontal and that, for the maximum speed of this movement, said inclination has a value for which the rear end of the cradle remains immersed at a shallow depth, of the order of what ques tens of cm on average (point A, figure 2).

The wing 8, or the front or rear end of this wing, which is the most deeply submerged, is preferably mounted pivotally about a transverse horizontal axis Y, its pivoting having the effect of modifying the ramp inclination 5.

The changes in orientation of the wing 8 are controlled from the ship anywhere desirable mechanism-such as a linkage (not shown).

A suitable device shown diagrammatically in FIG. 1 by cables 9 and by a crank winch 10 mounted on the ship serves to raise the ramp 5 against the switchboard of the ship outside of its periods of service.

• - une barre arrière horizontale 8₃ résistant à la flexion,
• - une autre barre supérieure horizontale avant 8₄ résistant à la flexion et s'étendant selon l'axe de pivotement X de la rampe, et
• - un caisson 8₅ voisin de cette dernière barre 8₄, caisson de section relativement importante auquel est confié l'essentiel de la mission de raidissement du berceau.

In addition to the wings 8, and 8 ₂ , the spacers which connect the members 7 include:

• - a horizontal rear bar 8 ₃ resistant to bending,
• another front upper horizontal bar 8 ₄ resistant to bending and extending along the pivot axis X of the ramp, and
• - A box 8 ₅ adjacent to this last bar 8 ₄ , a box of relatively large section to which most of the stiffening mission of the cradle is entrusted.

At least some of the different components 8, 81, 8 ₂ are themselves constituted by hollow boxes of low density so that when the ship stops the cradle "floats" on the water at a level close to those that it occupies during movement of the ship, the rear end of this cradle then being substantially at the same level as the water, as shown at B in FIG. 2.

The boxes in question are for example made of a light alloy or a composite based on resin and glass or carbon fibers.

The cable ply is made up of cables 6 extending parallel to each other between the two bars 8 ₃ and 8 ₄ and stretched by any suitable means such as turnbuckles (not shown) mounted on the front portions of the cables. .

These cables 6 consist in particular of metal cores, preferably of steel, surrounded by a sheath of a plastic material having good resistance to sea water and to friction, this material being for example one of the following: PTFE, polyethylene, polypropylene or polyvinyl chloride.

The natures, sections, numbers and mutual distances of the cables 6 are chosen so as to constitute a support that is both simple and solid for the boats 2 to board and disembark.

The sheet formed by these cables 6 can be unique and then extends without significant discontinuity over the entire width of the cradle.

Such a solution can be envisaged when the hulls of boats 2 do not have a significant lower projection such as that formed by a propelling propeller: such boats are for example those with a flat bottom which are moved by an aerial propeller or for which the marine propeller is permanently retracted inside a chute or can be retracted upwards as desired, in particular by tilting the propulsion unit as is the case for certain outboard motors.

The preferred variant which has been illustrated in the drawings also lends itself to the embarkation of boats propelled by a rear marine propeller protruding slightly under the hull, in the median longitudinal vertical plane of this hull.

According to this variant, the ramp 5 is broken down into two half-ramps separated from each other by a free space E suitable for receiving such a propeller.

More precisely, the cradle described above consists of two identical half-cradles of which only the most distant portions of the cables 6 are joined transversely to each other.

In such a case, each half-cradle is delimited laterally by two ribs 7 bent in V and only the spacers designated above by the references 8, and 8 ₅ extend over the entire width of the cradle, that is to say -display both over the entire width of each half-cradle and between them: on the contrary the three spacers designated by the references 8 ₂ , 8 ₃ and 8 ₄ extend only over the width of each half-cradle and are interrupted between them to clear space E.

The cable ply here comprises two half-plies each further composed of a set of parallel cables 6.

But here the directions of parallelism of the cables of the two half-plies are not parallel: these two directions converge slightly towards the front of the ship.

A converging tette has the advantage of automatically centering each boat on the ramp when it is docked.

As it is above all the cables 6 closest to the center of the ramp which are used for the support and the sliding guide of the boats, it may be advantageous to tighten these cables more in the vicinity of this center and / or to constitute them by materials more resistant than others to wear and breakage.

The number of cables 6 of each half-ply is for example of the order of ten.

In addition to the ramp 5 described above, means are provided for hauling towards the ship 1 and inside the garage 3 each boat 2 approaching this ramp or arriving in the vicinity thereof.

• - une perche (non représentée) terminée à son extrémité inférieure par une noix et suspendue élastiquement à un organe d'entraînement approprié tel qu'un câble sans fin tendu entre deux poulies dont une motrice, ainsi que bien connu dans le domaine des téléskis, et
• - une encoche 11 ménagée dans une platine triangulaire 12 rapportée sur la proue de chaque embarcation 2, encoche propre à recevoir la noix ci-dessus aux fins d'accrochage de l'embarcation sur la perche.

These means advantageously include:

• - a pole (not shown) terminated at its lower end by a nut and suspended elastically from a suitable drive member such as an endless cable stretched between two pulleys including a drive, as well known in the field of drag lifts, and
• - A notch 11 formed in a triangular plate 12 attached to the bow of each boat 2, clean notch to receive the nut above for the purpose of hooking the boat on the pole.

The operation of the boarding device described above is as follows.

The ship 1 moving forward at a speed V, which can be relatively high, it is proposed to embark on board a boat 2.

The ramp or "grid" 5 is lowered at the rear of the ship by the means 9, 10 and is therefore towed by it: as explained above, the inclination of this ramp then stabilizes at a value close to that of flotation at rest, value generally between 10 and 20 ° on the horizontal.

As soon as the boat 2, moved by its own motor at a speed V greater than V ,, arrives near the ramp 5 or berths it, the hauling means are hung on this boat: in the example described here above, this attachment involves a thrust of the pole and the housing of its terminal nut in the complementary notch of the boat.

With the help of these hauling means, the boat is hoisted onto the ramp, which receives the soft-sliding hull, that is to say without injuring it.

This shell is automatically centered thanks to the convergence of the two half-plies of cables, so that the propeller projecting under this shell is automatically received in the space or channel E reserved between the two half-plies.

The hauling can thus be continued until the complete introduction of the boat into the garage.

According to a possible variant when the ramp is long enough, as soon as most of the boat has reached this ramp, it is raised by an angle sufficient for its rear end to exceed the level of the garage floor 4 : the end of the introduction of the boat in this garage can then be done by gravity, at least in part.

The landing maneuvers involve the reverse sequence of the above operations, in the reverse order of the previous one.

It should be noted that due to the particular forms adopted for the constituent elements of the cradle, the ship can move in reverse without it being necessary to raise the ramp, the latter not risking diving then and reaching in contact with the propeller of this ship.

According to an improvement, the implementation of which may be of interest for boarding carried out in heavy weather or in a hostile environment, the lifting of the ramp is automatically ordered as soon as the boat to be boarded has arrived, by its own means, high enough on this ramp, said command then being slaved to the abutment of the nose of this boat against an appropriate range of the ship situated for example on the rear vertical face of the central section of the box 8 ₅ .

Then what, and whatever the embodiment adopted, we finally get a device for embarkation and disembarkation of boats whose constitution, operation and advantages (including the simplicity of implementation and the possibility of 'to carry out embarkations even when the carrier ship is in motion) result sufficiently from the above.

• - celles où plusieurs rampes indépendantes seraient remorquées par un même navire, rampes desservant respectivement des garages différents sur ce navire,
• - celles où la nappe de câbles constitutive de la surface porteuse de la rampe serait remplacée par une autre nappe souple, notamment par l'ensemble d'unetelle nappe et d'un taud tendu sur celle-ci et accroché sur ses câbles extrêmes en vue d'assurer l'embarquement d'embarcations reposant sur l'eau par l'intermédiaire d'un coussin d'air.

As is obvious, and as already follows from the foregoing, the invention is in no way limited to those of its modes of application and embodiments which have been more especially envisaged; on the contrary, it embraces all variants, in particular:

• - those where several independent ramps would be towed by the same ship, ramps respectively serving different garages on this ship,
• - those where the cable ply constituting the carrying surface of the ramp would be replaced by another flexible ply, in particular by the assembly of such a ply and an awning stretched over it and hung on its end cables in view to ensure the embarkation of watercraft based on an air cushion.

Claims (4)

1. Device for hoisting a boat on board a ship and for placing this boat in the water from this ship, comprising a rampe (5) coupled to the rear of the ship (1) for pivoting about a horizontal transverse axis (X) related to the ship, which ramp is adapted for supporting the boat between the water and a reception zone (3) provided on board the ship, characterized in that the ramp (5) is formed by an array of cables (6) stretched over a V shaped cradle (7, 8) itself formed from longitudinal members (7) extending in a widely open V and horizontal cross pieces (8) tying these members together, the component elements of said cradle likely to be immersed all having a small cross section so that the drag resistance generated by their immersion is very small.

2. Hoisting in device according to Claim 1, characterized in that the cradle is divided into two substantially identical half cradles secured together by tying together their portions the furthest removed from the array of cables (6).

3. Hoisting in device according to Claim 2, characterized in that the two half arrays of cables carried respectively by the two half cradles are each formed from parallel cables (6) and in that the directions of these two arrays converge towards the front of the ship (1).

4. Hoisting in device according to any one of the preceding claims, characterized in that means are provided for automatically using, for the purpose of controlling raising of the ramp (5), the impact of the front of each boat to be hoisted in against a facing abutment carried by the ship (1).

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