EP2697113A1

EP2697113A1 - Retractable boat keel

Info

Publication number: EP2697113A1
Application number: EP12722418.6A
Authority: EP
Inventors: Philippe BECEL
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-04-14
Filing date: 2012-04-13
Publication date: 2014-02-19
Anticipated expiration: 2032-04-13
Also published as: EP2697113B1; FR2974058A1; FR2974058B1; WO2012140379A1

Abstract

The invention relates to a boat (1), for example a yacht, comprising a hull (3), at least one keel (4) and at least one system for folding down the keel and designed to pivot said keel about a first rotation axis (XI) defined in a transverse direction on the boat and to pivot at least a part (6) of said keel about a second rotation axis (X2) defined in a longitudinal direction on the boat, so as to move the keel from a defined position in a more or less vertical and more or less longitudinal plane (P) on the boat to a flat position in the lengthwise direction under the hull, and vice versa.

Description

RETRACTABLE BOAT

The present invention relates to a boat, in particular boats of the sailboat type with variable draft. However, it is possible to envisage the implementation of the present invention on other types of boats. Sailboats are generally equipped with a keel arranged under the hull of the boat. The function of this keel is twofold: first an anti-drift function and then a ballast function to generate a righting torque as soon as the boat is lying.

In a general manner, with equivalent keel surface, these two functions mentioned above are all the more assured that the keel is deep. Indeed, the lift developed by the plane of drift is all the more important that the keel of the boat is deep and narrow. Furthermore, the rectification torque produced by the ballast is all the more important that the ballast is placed in the lower position and therefore, that the keel is deeper. This type of boat has the characteristic of having a strong draft.

In return, the boats with deep draft have the disadvantage of not being able to access the shallow water bodies, to fail with difficulty and to be difficult to transport.

It follows that for a very long time attempts have been made to reconcile these contradictory requirements by designing boats with variable draft, equipped with a lifting or lifting keel. It is understood that the object of the present invention will focus on the lifting system of the keel or drift implemented on the boat.

In the remainder of the description, reference will be made especially to sailboat type boats equipped with lifting keels. However, the term "lifting keel" means both the lifting keels and the lifting keels. Indeed, the difference between liftable and lifting keels is related to their weight. The drifts are generally relatively light and their weight intervenes little, or not at all, in the righting torque of the boat. On the contrary, the lifting keels integrate all or part of the ballast of the boat. The fact remains that the invention can be implemented on any type of boat equipped with a keel or a drift. Thus, there are known boats equipped with a hull, a keel or a drift and a system for lifting the keel or the fin. Various designs of lifting systems of the keel or the drift on the boat are described for example in the document US.2.553.372, FR.936.478, US.1.703.868, FR.2.328.366, US.433.955, FR .1.545.615, FR.1.467.968, FR.1.430.517, GB.2.362.356 and US.3.776.171.

According to the documents US.2.553.372, FR.936.478, US.1.703.868 and FR.1.430.517, there is described a boat which comprises a keel or a fin consisting of one or two elements mounted in pivot connection under the hull of the boat along a longitudinal axis arranged according to the plane of symmetry of the boat and to rotate the keel flat under the hull of the boat, on one side of the axial plane of symmetry of the boat. This design has some drawbacks when the boat is equipped with a deep keel, it can significantly exceed the side of the boat when folding flat under the hull. This can present an inconvenience during the transport on trailer of said boat.

According to the documents US.433.955, FR.1.545.615, FR.1.467.968 and GB.2.362.356, the boat comprises a keel well or drifting well allowing an integral retraction of the keel or the drift by means of a system for actuating said keel. A disadvantage of this type of design is that the keel well or drifting well encroaches in the fittings of the boat, which limits the living space and constitutes a real nuisance, especially on small boats.

An interesting solution, as described in document FR.2.328.366, is to design a keel or a pivoting dagger along a transverse axis of rotation on the boat and whose keel fin remains partly outside the shell. Indeed, only the head of the keel or the drift is arranged inside a keel well or drifting well. Thus, the keel well or drift well receiving only the keel or drift head is smaller and encroaches less in the interior space of the boat. However, this implementation has the disadvantage of involving a smaller reduction of the draft and requiring the Crutches are present when the boat is stranded due to the presence of the keel fin under the hull of the boat.

According to the document US Pat. No. 3,776,171, there is described a keel which is mounted on a pivoting shaft under the hull of the boat along an inclined axis of rotation. The particular shape of the keel, combined with its pivoting along the inclined axis of rotation, makes it possible to move the keel from an extended position generating a maximum of draft to a raised position allowing a reduction of the draft and navigation in shallower water. A disadvantage of this design is the shaft which has to withstand significant forces due to the very large hydrodynamic forces exerted on your keel in the deployed position during navigation. This design therefore requires the implementation of a large diameter shaft, or oversized, to prevent its rupture which could cause the loss of the keel and consequently a loss of stability of the boat.

The object of the present invention is to overcome the aforementioned drawbacks. As such, the object of the present invention is to implement a boat equipped with a lifting system of the keel or the drift whose design reduces the encroachment of the drift well or well keel inside the livable space of the boat and to be perfectly adapted for the boats equipped with drift but also for the boats equipped with shallow keel or on the contrary very deep without constituting an embarrassment during the raising of the drift or keel.

For this purpose, the present invention relates to a boat comprising a hull and at least one keel. Indeed, the invention could be implemented on a boat that has more than one keel, in particular two-keel sailboats. According to the invention, the boat comprises at least one keel lifting system configured to pivot said keel according to a first axis of rotation defined in a transverse direction on the boat and to rotate at least a portion of the keel according to a second axis of rotation defined in a longitudinal direction on the boat so as to move the keel from a defined position in a more or less vertical plane and more or less longitudinal on the boat to a position flat and in the direction of the length under the hull, and conversely when deploying the keel. We understand that the positioning of the keel flat and in the direction of the length under the hull of the boat has the advantage of optimizing the reduction of the draft and to be able to fail the boat without requiring the use of crutches. The positioning of the keel in the direction of the flat length under the hull of the boat is moreover perfectly adapted to deep keels which are positioned properly under the hull of the boat in the direction of the length and not laterally on the one side sides of the boat as is the case according to the prior art which, in the case of a deep keel, has the disadvantage of increasing the size of the boat in the width direction, especially during operations transport on trailer. This design also has the advantage of considerably limiting the size of the keel well in the interior space of the boat or, according to the design of the lifting system of the keel of the boat object of the invention, allows to remove it completely.

It is understood that a keel lifting system is implemented for each of the pins on the boat.

According to a preferred mode of design, the boat object of the invention comprises a keel well. In addition, the keel comprises a head defined in a vertical and longitudinal plane on the boat and a fin. In the normal position of use, the fin is positioned more or less in the same plane as the head. The head is pivotally connected to the interior of the keel well according to the first axis of rotation defined in a transverse direction on the boat and the fin is pivotally mounted relative to the head according to the second axis of rotation defined in a plane more or less vertical and more or less longitudinal on the boat. Thus, only the head is arranged inside the keel well, which limits the size of said keel well in the interior space of the boat. It is understood that the pivoting of the head according to the first axis of rotation makes it possible to turn the fin in the more or less vertical plane and more or less longitudinal under the boat, this spoiler can then be positioned flat under the boat by pivoting in relation to the head.

The term "more or less vertical plane and more or less longitudinal" the fact that on some boats, including boats equipped with a single keel, said keel is positioned in the plane of axial symmetry of the boat and, in this case, the keel is positioned in a vertical and longitudinal plane on the boat. In Other variants of the design of the boat object of the invention, these may include several pins which are positioned in slightly inclined planes with respect to the axial plane of symmetry of the boat. This is the case for example on two-keel boats, well known in navigation, where two keels are arranged symmetrically with respect to each other, with respect to the plane of axial symmetry of the boat, with in general a slight inclination with respect to said plane of axial symmetry. It is understood that in this case, the keels are positioned in more or less vertical and more or less longitudinal planes on the boat during navigation, and are therefore likely to pivot from these planes to a flat position and in the longitudinal direction under the hull of the boat by means of reefing system implemented on the boat object of the invention.

According to this preferred mode of design of the boat object of the invention, the keel well is configured to receive the head and a proximal portion of the fin at which is arranged the pivot connection with said head, along the second axis of rotation. Thus, when the fin and the head are arranged in the same plane and the keel is in the deployed position of use, generating a large draft, it is understood that the proximal portion of the fin and the head are arranged inside the keel well and that, therefore, the pivot connection between the head and the fin along the second axis of rotation is also arranged, at least in part, inside the keel well, which limits the pivoting of the fin relative to the head so as to keep the fin more or less in the same plane as the head. Indeed, the proximal portion of the fin, disposed in the keel well, in this case abuts against the keel well when the fin tends to rotate relative to the head along the second axis of rotation.

According to this preferred mode of design of the boat object of the invention, the pivot connection between the head and the fin is arranged to pivot from a position inside the keel well when said keel is deployed, to a position to the outside of the keel well during the pivoting of the head along the first axis of rotation for the lifting of said keel. It is understood that this positioning of the pivot connection and therefore the second axis of rotation outside the keel well will allow the pivoting of the fin relative to the head so as to position it flat under the hull of the boat . According to this preferred mode of design of the boat object of the invention, the fin comprises a rear distal end, the fin being configured so that the rear distal end comes into contact with the boat hull during a rotation of said flap with the head, according to the first axis of rotation, that is to say in the longitudinal vertical plane. This input contact of the rear distal end with the hull of the boat has the advantage of engaging the pivoting of the fin relative to the head, according to the second axis of rotation.

According to this preferred mode of design of the boat object of the invention, rolling means are arranged between the shell and the rear distal end to promote the pivoting of the fin relative to the head when said rear distal end comes into contact. with the shell and exerts a force against said shell due to pivoting of the head along the first axis.

According to this preferred embodiment of the boat object of the invention, the rolling means consist of a raceway arranged on the shell and at least one roller arranged at the rear distal end of the flap. , the rolling roller moving in the raceway when said rear distal end exerts a force against said shell. According to this preferred embodiment of the boat object of the invention, the raceway is arranged transversely under the hull with an inclination, to generate the pivoting of the fin relative to the head.

According to this preferred mode of design of the boat object of the invention, when the fin is in the same longitudinal vertical plane as the head, the second axis of rotation forms an angle Θ with a line D passing through the contact point of the distal rear end with the shell and perpendicular to the first axis of rotation.

According to this preferred embodiment of the boat object of the invention, it comprises a head actuating system configured to cause the rotation of said head along the first axis of rotation. Preferably, the actuating system is a jack arranged between the head and the keel well. This jack can be a worm cylinder, a hydraulic cylinder or other.

According to this preferred mode of design of the boat object of the invention, the keel well opens at the bottom on a passage opening of the keel, arranged on the hull. In addition, this opening on the hull is trapezoidal shaped configured to allow angular movement of the fin relative to the head along the second axis of rotation when the keel is more or less unfolded.

Thus, this trapezoidal opening on the hull allows the aileron to pivot with respect to the head along the second axis of rotation, when the proximal portion of this fin is positioned inside the keel well, c that is to say when the keel is in the deployed position, which allows an angular deflection having many advantages, in particular on current hulls of sailboats, wide, flat and planing. In fact, this angular displacement makes it possible to have a variable incidence of the longitudinal vertical plane of the fin of the keel, with respect to the plane of axial symmetry of the boat. This increases the performance of the boat to closely close, especially on a flat sea. In addition, when the vessel is tacking upwind, the present invention has the advantage of effecting a change in the incidence of the keel fin from one side edge to the other side edge of the trapezoidal shape, automatically under the effect of the pressure of the water exerted on said keel fin. Thus, the keel fin is self-steerable.

According to this preferred mode of design of the boat object of the invention, said boat comprises a system for adjusting an angular deflection β 'of the fin relative to the head. This adjustment system makes it possible to modify the angular deflection β 'so as to allow more or less the pivoting of the fin relative to the head when the proximal portion of said fin passes through the passage opening on the hull and is arranged inside the keel well. This makes it possible to adjust the adjustment of the variable incidence of the longitudinal vertical plane of the fin with respect to the plane of axial symmetry of the boat.

Preferably, the angular deflection adjustment system is arranged on the keel well. This angular deflection adjustment system comprises two stops arranged respectively on the lateral sides of the keel well. The keel fin can come to bear on these two stops during its pivoting relative to the keel head along the second axis of rotation, which limits its pivoting. Means for adjusting the position of the stops are in further arranged between said stops and said lateral sides of the keel well and allow to modify the spacing between the two stops and thus the angular deflection β '. Preferably the adjustment of the angular deflection β 'may vary between 0 ° and 30 °.

According to the invention, the boat comprises at least two support pads arranged on each side of the keel and configured to come into contact with the ground when the keel is folded flat under the hull of the boat, for the stranding of said boat . This prevents the keel from touching the ground during the grounding.

According to the invention, the hull of the boat comprises a housing configured to receive at least the portion of the keel which is positioned flat and lengthwise under said hull, namely the keel fin according to the preferred embodiment of the invention. aforementioned design. This does not exclude that, in design variants, this housing can fully receive the keel folded flat in the direction of the length under the hull.

The features and advantages of the present invention will appear on reading the following description of a preferred mode of design based on figures among which:

- Figure 1 illustrates a keel arranged under the hull of a boat object of the invention in side view, the keel being deployed in the maximum position providing a maximum draft;

- Figure 2 illustrates the keel under the hull of the boat object of the invention raised in an intermediate position allowing a reduction of the draft;

- Figure 3 shows a side view of the keel in maximum raised position according to which the keel is folded under the hull of the boat in the direction of the length of the boat;

FIG. 4 illustrates a view from below of the keel illustrated in FIG. 3;

- Figure 5 illustrates an example of a boat showing the plane of axial symmetry of the boat;

- Figures 6 to 8 illustrate a partial view of the side, bottom and back of a housing implemented on the hull of the boat to receive the keel in the folded position flat in the direction of the length under said hull; and - Figure 9 schematically an alternative design of the boat object of the invention highlighting the presence of two pins under the hull. In the example described below, it is considered that the boat has a single keel arranged in the plane of axial symmetry P shown in Figure 5. Thus, the boat 1 comprises a single keel well 2 arranged under the hull 3 of the Boat 1 according to this plane of axial symmetry P. This plane of axial symmetry P of the boat is also shown in Figures 1 to 4.

However, we can consider the implementation of the present invention on other types of boats with more than one keel. For example, in FIG. 9, two pins 4'a, 4'b are arranged under the shell 3 'symmetrically with respect to said axial plane of symmetry P' of the boat. In this case, the two keels 4'a, 4'b are defined in two planes PI and P2 symmetrical with respect to the plane of axial symmetry P 'and each having a slight inclination with respect to said axial plane of symmetry P'. It is considered in this case that the two pins 4'a, 4'b are defined in two planes PI and P2 more or less vertical and more or less longitudinal on the boat the. Other variants can be envisaged on this principle.

In the example described below, reference is further made to a boat equipped with a keel 4 and a keel well 2. Of course, the object of the present invention also covers drift-equipped boats. and a drift well as previously specified.

It is noted with reference to Figures 1 to 3 that the boat 1 object of the invention comprises a keel lifting system. This keel lifting system allows to position the keel 4 in a fully deployed position as shown in Figure 1 with a maximum draft. The lifting system also allows to raise the keel 4 to an intermediate position shown in Figure 2 to reduce the draft and navigate in shallow bodies of water. The lifting system on the boat object of the invention also allows to completely fold the keel 4 flat under the hull 3 of the boat 1 as illustrated in Figures 3 and 4. It is found that the keel 4 is disposed to flat under the hull in the direction of the length of the boat. It can be seen that the keel 4 comprises a first part constituting a head 5 and a second part constituting a fin 6. With reference to FIGS. 1 to 4, it can be seen that the head 5 is pivotally mounted inside the keel well 2 at the means of a pivot connection 7 allowing a rotation of said head 5 as well as the fin 6 with respect to a first axis of rotation XI arranged in the transverse direction on the boat. It can be seen from FIGS. 1 to 4 that the fin 6 and the head 5 are mounted in pivot connection 8 with respect to each other, which allows the fin 6 to pivot relative to the head 5. along a second axis of rotation X2 disposed in a longitudinal vertical plane in which is defined the head 5, which is coincident with the plane of axial symmetry P of the boat according to the example described here.

The fin 6 comprises a rear distal end 9 which comprises a roller 10 rotatably mounted on said rear distal end 9 as illustrated in Figures 1 to 4.

It can be seen that during the pivoting of the keel 4 from a position illustrated in FIG. 1 to a position illustrated in FIG. 2, the roller 10 comes into contact with the hull 3 of the boat 1. This contact is made possible by by the shape of the keel 4 and in particular the fin 6, the distal portion 6a is inclined relative to the proximal portion 6b, as can be seen in Figures 1, 2 and 4.

It is also noted that the hull 3 of the boat 1 comprises a raceway 11 on which the rolling roller 10 can be rotated.

The keel well 2 opens onto an opening 12 arranged on the shell 3, as shown in FIG. 4, through which the head 5 and the proximal portion 6b of the fin 6 pass during the pivoting of the keel according to FIG. axis XI.

As can be seen with reference to FIG. 1, when the keel 4 is deployed completely or in part, the proximal portion 6b of the fin 6 is engaged in part in the keel well 2 with the head 5, which limits the pivoting of the fin 6 relative to the head 5 along the axis of rotation X2 since the proximal portion 6b of the fin 6, engaged in the keel well 2, can not pivot beyond the lateral edges 12a, 12b of the opening 12. Thus, the flap 6 remains more or less positioned in the longitudinal vertical plane of the head 5.

As can be seen in Figure 2, when the roller 10 comes into contact on the raceway 11 arranged on the hull 3 of the boat 1, the second axis of rotation X2, at which is arranged the pivot connection between the fin 6 and the head 5, is positioned outside the keel well 2, which allows the pivoting of the fin 6 relative to the head 5 along said axis of rotation X2. For this purpose, the pivoting of the fin 6 with respect to the head 5 along the second axis of rotation X2 is caused by the force exerted by the roller 10 on the raceway 11 on the hull, this force being generated by the downward rotation in the direction of the arrow 13 illustrated in Figure 3, the head 5. Thus, the rotation of the head 5 along the axis XI, in the direction of the arrow 13, allows the pivoting the fin 6 flat under the hull of the boat as shown in Figures 3 and 4. It is noted in Figure 4 that the direction of rotation of the fin 6 relative to the head 5 along the axis of rotation X2 which is defined in the plane of axial symmetry P is inverse to the position of the raceway 11 which is disposed on the other side of the plane of axial symmetry P. Thus, in FIG. 4, the fin is pivoted to flat under the shell on one side of the plane of axial symmetry P and the raceway 11 is disposed on the other side of the plane of symmetry In order to generate the pivoting of the fin 6 with respect to the head 5, this race has a slight inclination favoring the rolling of the roller 10 and thus the pivoting of the fin 6 in the opposite direction.

FIG. 2 shows that when the roller 10, arranged at the rear distal end 9 of the fin 6, comes into contact with the shell 3, in the raceway 11, the point of contact between the roller 10 and the raceway 11 and the point of intersection 14 between the axis of rotation XI, transverse on the boat and the axial plane of symmetry P, as shown in Figure 4, define a straight line D is illustrated in FIG. 2. This straight line D is defined in the plane of axial symmetry P. It can be seen that this straight line D and the straight line passing through the second axis of rotation X2 define an angle Θ, which makes it possible to generate the pivoting of the 6 against the head 5 when the roller 10 comes into contact with the raceway 11. Preferably the angle Θ will be between 5 ° and 40 ° and will depend in particular on the shape of the hull 3 of the boat 1.

It can be seen in FIG. 4 that the opening 12 on the shell 3 has a trapezoidal shape whose lateral sides 12a, 12b define an angle β. When the keel 6 is more or less extended, that is to say in a position from Figure 1 to approximately Figure 2, the proximal portion 6b of the fin 6 is partly engaged in the well of keel 2, which limits the pivoting of said fin 6 relative to the head 5 according to the second axis of rotation X2. The trapezoidal shape of the opening therefore allows an angular deflection β of the fin 6 when it is more or less deployed. This increases the performance of the boat up close.

FIGS. 1 to 4 show that two threaded rods 18a, 18b are respectively sealed on the lateral sides 2a, 2b of the keel well 2. These threaded rods 18a, 18b are screwed onto the lateral sides 2a, 2b The ends of these threaded rods 18a, 18b constitute two abutments 19a, 19b on which the fin 6 of the keel 4 comes to bear when it is pivoted in one direction or the other according to FIG. axis of rotation X2, relative to the head 5, and when the proximal portion 6b of the fin 6 is engaged in part in the keel well 2. These two stops 19a, 19b limit the angular deflection β 'of the fin 6. In addition, the modification of the screwing position of the threaded rods 18a, 18b makes it possible to modify the position of the stops 19a, 19b and thus to adjust the angular deflection β 'limiting more or less the pivoting of the fin 6 relative to at the head 5.

These threaded rods 18a, 18b are manipulated from inside the boat, the keel pit 2 being accessible from the living space of said boat. In order to facilitate the adjustment of the angular deflection β ', manipulation handles 20a, 20b of the threaded rods 18a, 18b are provided, as well as a register for precisely adjusting the position of the stops 19a, 19b and thus the angular deflection β' .

Preferably the angular deflection β 'will be adjustable between 0 ° and 30 ° (0 °

<β '<30 °). The setting at 0 ° corresponds to a first extreme position in which the fin 6 is completely blocked and arranged in alignment with the 5. On the other hand, the adjustment at 30 ° corresponds to a second extreme position according to which the variable incidence is maximum, the fin 6 being able to pivot from -15 ° to + 15 ° on one side and the other by This second extreme position where the angular deflection β 'is maximum can for example correspond to the angle β defined between the lateral sides 12a, 12b of the opening 12 which then limit the pivoting of the fin 6 .

FIGS. 1 to 3 show the presence of a jack 15 which is arranged between the head 5 and the keel well 2. The actuation of this jack 15 makes it possible to control the rotation of the head 5 along the first axis XI as seen in Figures 1 to 3. Preferably, the cylinder 15 is the worm cylinder type manually operated by means of a crank. However, it is possible to envisage the implementation of a cylinder of the hydraulic type or electrical or other. Other actuating systems arranged between the keel well 2 and the head 5 of the keel 4 could also be envisaged. This actuation system could also be arranged between the hull 3 and the keel 4, according to other configurations. of the lifting system of said keel.

FIG. 4 shows the presence of two bearing pads 16a, 16b arranged on each side of the plane of axial symmetry P and on each side of the keel 4. These bearing pads 16a, 16b are of a slight height greater than the thickness of the fin 6 of the keel protruding under the hull, which allows, when the fin 6 is folded flat under the hull 3 of the boat 1 as shown in Figures 3 and 4, to allow the support pads 16a, 16b to come into contact with the ground during the grounding of the boat, thus avoiding direct contact of the fin of the keel folded under the hull, with the ground.

It can be seen in FIGS. 6 to 8 that the hull 3 of the boat 1 comprises a housing 17 which is configured to receive the keel 4 in the folded position flat in the direction of the length, under the said hull 3. In the context of the preferred embodiment described above, this housing 17 allows the reception of the fin 6 of the keel 4. It is noted that the two bearing pads 16a, 16b are respectively disposed on the lateral sides of the housing 17 under the shell 3.

Other characteristics may be envisaged without departing from the scope of the present invention. In particular, it will be possible to implement variants of design of the lifting system of the keel to fully fold down said keel flat lengthwise under the hull 3 of the boat 1, incorporating some of the aforementioned characteristics, for example the implementation of the support pads 16a, 16b and housing 17 arranged on the shell 3.

In addition, the keel is preferably configured to ensure a balance of the boat when said keel is folded flat under the hull 3 and thus ensure a balanced flotation of said boat. For this, weighting means are implemented with a balanced distribution on the distal portion 6a of the fin 6.

In the case of design variants of the boat which is the subject of the invention, for example a twin-keel boat as schematized in FIG. 9, having technical characteristics similar to those described above, that is to say that the keels 4'a, 4'b each consist of a head and a flap pivotally mounted relative to each other, the heads of the pins 4'a, 4'b are respectively defined in the plans PI and P2 and rotate according to the respective first axes of rotation X and X "1. These axes of rotation ΧΊ and X" 1 are perpendicular to the respective planes P1 and P2 and more or less transversely arranged on the boat. Likewise, the fins of the pins 4'a, 4'b pivot relative to these heads along two second axes of rotation X'2 and X "2 defined in the respective planes P1 and P2.These ailerons pivot from a position defined in the planes of the heads, that is to say the planes PI and P2, to a position lying flat longitudinally under the hull 3 'of the boat, in which case these second axes of rotation X'2 and X " 2 are more or less defined in the longitudinal direction on the ship the,

Claims

A boat (1) comprising a hull (3) and at least one keel (4), characterized in that it comprises at least one keel folding system configured to pivot the keel along a first axis of rotation ( XI) defined in a transverse direction on the boat and to rotate at least a portion (6) of said keel along a second axis of rotation (X2) defined in a longitudinal direction on the boat, so as to move the keel of a position defined in a plane more or less vertical and more or less longitudinal (P,

PI, P2) on the boat to a position flat and in the direction of the length under the hull, and vice versa.

2. Boat (1) according to claim 1, which comprises a keel well (2), the keel (4) having a head (5) defined in the plane more or less vertical and more or less longitudinal (P, PI, P2) and a fin (6), the head (5) being mounted in pivot connection (7) inside the keel well according to the first axis of rotation (XI) and the fin (6) being mounted in connection with pivot (8) relative to the head according to the second axis of rotation (X2) to rotate the fin from a defined position in the plane of the head to a flat position and in the longitudinal direction under the hull of the boat.

3. Boat (1) according to claim 2, the keel well (2) being configured to receive the head (5) and a proximal portion (6b) of the fin (6) at which is arranged the pivot connection (8) with said head, according to the second axis of rotation (X2).

4. Boat (1) according to claim 2 or 3, the pivot connection (8) between the head (5) and the fin (6) is arranged to pivot from a position inside the keel well (2). ) to a position outside the keel well when pivoting the head along the first axis of rotation (XI), for lifting the keel (4).

5. Boat (1) according to any one of claims 2 to 4, wherein the flap (6) comprises a rear distal end (9), the fin being configured so that the rear distal end comes into contact with shell (3) of the boat during a rotation of said flap along the first axis of rotation (XI).

6. Boat (1) according to claim 5, wherein rolling means (10,11) are arranged between the shell (3) and the rear distal end (9) to promote the pivoting of the fin (6). relative to the head (5) when said rear distal end contacts the shell and exerts a force against said shell.

7. Boat (1) according to claim 6, wherein the rolling means consist of a raceway (11) arranged on the shell (3) and at least one roller (10) arranged at the end. rear distal (9), the roller moving in the raceway when said rear distal end exerts a force against said shell.

8. Boat (1) according to claim 7, wherein the raceway (11) is arranged transversely with an inclination on the shell (3).

9. Boat (1) according to one of claims 2 to 8, wherein the second axis of rotation (X2) forms an angle Θ with a straight line D passing through the point of contact of the rear distal end (9) with the shell (3) and perpendicular to the first axis of rotation (XI), when the fin (6) is in the same plane as the head (5).

10. Boat (1) according to any one of claims 2 to 9, which comprises an actuating system (15) of the head (5) configured to cause the rotation of said head along the first axis of rotation (XI) .

11. Boat (1) according to claim 10, wherein the actuating system is a jack (15) arranged between the head (5) and the keel well (2).

12. Boat (1) according to any one of claims 2 to 11, wherein the shell (3) comprises an opening (12) for passing the keel (4), the opening being of trapezoidal shape configured to allow a angular deflection β of the fin (6) relative to the head (5) along the second axis of rotation (X2) when the fin is deployed.

13. Boat according to claim 12, which comprises an adjustment system (18a, 18b) of an angular deflection β 'of the fin (6) configured to limit more or less the pivoting of the fin (6) relative at the head (5).

14. Boat (1) according to claim 13, wherein the adjustment system (18a, 18b) allows adjustment of the angular deflection β 'between 0 ° and 30 ° (0 ° <β' <30 °).

15. Boat (1) according to any one of claims 1 to 14, which comprises at least two support pads (16a, 16b) arranged under the shell (3) on each side of the keel (4) and configured to come in contact with the ground when folding the keel flat under the hull.

16. Boat (1) according to any one of claims 1 to 15, wherein the shell (3) comprises a housing (17) configured to receive at least the portion (6) of the keel (4) folded flat in the direction of the length under the shell (3).