FLOATING MARITIME VESSEL COMPRISING A DETACHABLE MEASURING KEEL

Abstract

The invention relates to a floating maritime vessel including at least one hull beneath a deck, the hull extending between a bow and a stern in a longitudinal direction of the vessel, the vessel including, on its lower part, a removable keel and, on its upper part, a conning tower erected above the deck, the keel being able to be descended below the hull and raised back through the hull, the keel including a lower end and an upper end, the upper end of the keel connecting to the hull when the keel is in its lowered position. According to the invention, the conning tower contains a keel-storage space and the keel and the keel-storage space of the conning tower are aligned such that the keel can be raised by upward translation at least partly into the keel-storage space of the conning tower.

Claims

1. A floating marine craft (1) comprising at least one hull (2) topped with a deck (4), the hull (2) extending between a bow and a stern along a longitudinal direction of the craft (1), the craft (1) comprising, in a lower part, a removable keel (3), and in an upper part, a wheelhouse (9) erected above the deck, the keel (3) being able to be lowered under the hull (2) and lifted through the hull (2), the keel having a lower end and an upper end, the upper end of the keel being connected to the hull when the keel is in lowered position, wherein the craft (1) is a motor-driven single-hull drone and its hull (2) is fusiform and tapered and the craft is wave-piercing, the craft (1) having a total length lower than 20 metres and higher than 2.5 metres, with a total width to total length ratio lower than 0.2, the lowered keel (3) comprising a ballast providing the transverse stability to the craft (1), and wherein the wheelhouse (9) internally contains a keel-storage space (13) and wherein the keel (3) and the keel-storage space (13) of the wheelhouse (9) are arranged in alignment with each other so that the keel (3) can be lifted by upward translation at least partly into the keel-storage space (13) of the wheelhouse (9).

2. The craft (1) according to claim 1, wherein the keel (3) comprises, in a lower end, a longitudinally elongated bulb (6) connected to the upper end of the keel (9) by a connection part (5) of the keel of longitudinal extent lower than the longitudinal extent of the bulb (6), and when the keel (3) is lifted within the wheelhouse (9), the bulb (6) remains under the hull.

3. The craft (1) according to claim 2, wherein the connection part (5) of the keel (3) has a uniform cross-section over a height thereof.

4. The craft (1) according to claim 2, wherein the bulb (6) comprises an upper face turned upward and towards the hull (2) and a lower face turned downward and wherein the hull (2) comprises a recess at the connection of the hull (2) with the keel (3), wherein said recess can accommodate at least the upper face of the bulb (6) when the keel is lifted.

5. The craft (1) according to claim 1, further comprising a mechanism for lifting and lowering the keel (3), said mechanism being at least motor-driven.

6. The craft (1) according to claim 1, further comprising a means (11) for locking the keel in lowered position.

7. The craft (1) according to claim 1, further comprising a means (11b) for locking the keel in lifted position.

8. The craft (1) according to claim 6, wherein the locking means (11) is magnetic and controlled, the magnetic locking means comprising at least two complementary parts (11a, 11b) and magnetically interacting between each other, one of the parts being arranged on the keel (3) side and the other part, functionally complementary, being arranged on the hull (2, 12) side, and possibly, on the wheelhouse (9) side.

9. The craft (1) according to any claim 2, wherein the bulb (6) comprises a bow end and a stern end and wherein the bulb (6) is tilting at the lower end of the keel connection part (5) so as to place the bulb (6) and the keel connecting part (5) in axial continuity, and wherein the cross-sectional shape of the bulb (6), said cross-section being perpendicular to the longitudinal extent of the bulb, and the cross-sectional shape of the connection part (5) are adapted so as to allow the lifting of the bulb with at least one of the two bow and stern ends of the bulb (6) into the storage space (13) of the wheelhouse (9).

10. The craft (1) according to claim 2, wherein the craft is arranged so as to perform acoustic measurements and comprises acoustic measurement systems comprising acoustic wave transmitting and receiving transducers, and at least the acoustic wave transmitting and receiving transducers are arranged in the bulb of the keel.

11. The craft (1) according to claim 3, wherein the bulb (6) comprises an upper face turned upward and towards the hull (2) and a lower face turned downward and wherein the hull (2) comprises a recess at the connection of the hull (2) with the keel (3), wherein said recess can accommodate at least the upper face of the bulb (6) when the keel is lifted.

12. The craft (1) according to claim 4, further comprising a means (11b) for locking the keel in lifted position.

13. The craft (1) according to claim 7, wherein the locking means (11) is magnetic and controlled, the magnetic locking means comprising at least two complementary parts (11a, 11b) and magnetically interacting between each other, one of the parts being arranged on the keel (3) side and the other part, functionally complementary, being arranged on the hull (2, 12) side, and possibly, on the wheelhouse (9) side.

14. The craft (1) according to claim 1, wherein the keel (3) comprises, in a lower end, a longitudinally elongated bulb (6) connected to the upper end of the keel (9) by a connection part (5) of the keel of longitudinal extent lower than the longitudinal extent of the bulb (6), and the bulb (6) comprises a bow end and a stern end and wherein the bulb (6) is tilting at the lower end of the keel connection part (5) so as to place the bulb (6) and the keel connecting part (5) in axial continuity, and wherein the cross-sectional shape of the bulb (6), said cross-section being perpendicular to the longitudinal extent of the bulb, and the cross-sectional shape of the connection part (5) are adapted so as to allow the lifting of the keel with at least one of the two bow and stern ends of the bulb (6) into the storage space (13) of the wheelhouse (9).

15. The craft (1) according to claim 9, wherein the craft is arranged so as to perform acoustic measurements and comprises acoustic measurement systems comprising acoustic wave transmitting and receiving transducers, and at least the acoustic wave transmitting and receiving transducers are arranged in the bulb of the keel.

16. The craft (1) according to claim 14, wherein the craft is arranged so as to perform acoustic measurements and comprises acoustic measurement systems comprising acoustic wave transmitting and receiving transducers, and at least the acoustic wave transmitting and receiving transducers are arranged in the bulb of the keel.

17. The craft (1) according to claim 2, further comprising a mechanism for lifting and lowering the keel (3), said mechanism being at least motor-driven.

18. The craft (1) according to claim 3, further comprising a mechanism for lifting and lowering the keel (3), said mechanism being at least motor-driven.

19. The craft (1) according to claim 4, further comprising a mechanism for lifting and lowering the keel (3), said mechanism being at least motor-driven.

20. The craft (1) according to claim 2, further comprising a means (11) for locking the keel in lowered position.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0128] The following description in relation with the appended drawings, given by way of non-limitative example, will allow a good understanding of what the invention consists of and of how it can be implemented.

[0129] In the appended drawings:

[0130] FIG. 1 is a perspective view of a drone whose keel is lowered,

[0131] FIG. 2 is a perspective view of the drone of FIG. 1, whose keel is lifted,

[0132] FIG. 3 is a cross-sectional view passing through the keel of the drone of FIG. 1 and whose keel is lowered,

[0133] FIG. 4 is a cross-sectional view of an enlarged detail of the keel and of the drone of FIG. 1, and

[0134] FIG. 5 is a cross-sectional view passing through the keel of the drone of FIG. 1 and whose keel is lifted.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0135] By way of exemplary embodiment, it is considered a drone intended to perform marine explorations with measurements performed by measuring devices installed in the keel bulb.

[0136] In FIG. 1 is shown the floating/surface drone 1 of the invention, which is power-driven, herein with a propeller 8, and which comprises a very narrow fusiform hull 2. This very narrow hull does not provide a transverse stability to the craft 1, which has a very tapered shape so that, with this tapered stern hull, a wave-piercing craft is obtained. The underwater hull 10, the dead works and the deck 4 are hence configured to be of the “wave-piercing” type.

[0137] Towards the bottom of the hull 2, at the lower part of the underwater hull 10, is installed a keel 3 with a bulb 6. The bulb 6 being at the lower end of the keel 3, it is connected to the hull by a connecting part 5 of the keel 3. The keel 3 with a bulb 6 comprises, preferably in the bulb 6, a ballast that provides the transverse stability to the craft 1. This ballast is a specific heavy material, for example lead or tungsten, and/or corresponds to pieces of equipment, in particular measuring devices, installed in the bulb 6.

[0138] The craft 1 also comprises, in this example, a rudder 7.

[0139] Thanks to the very narrow shape of the hull 2 also visible in FIGS. 1 to 3 and 5, the craft 1 has a very low resistance to forward motion in view of its length. The hull 2 with the keel 3 allows minimizing the pitch movements. The hull 2 is capable of exceeding with very little energy the limit speed of the underwater hull and to reach overspeed without thereby having a so-called “hovering” shape.

[0140] The craft 1, whose total length is lower than 20 metres and with a minimum length of at least 2.5 metres, has a total width to total length ratio lower than 0.2. Preferably, the drone of the shown example has a length comprised between 2.5 m and 20 m.

[0141] The surface craft 1 of the invention, with its fusiform hull, is hence different from the traditional power-driven ships, which have a geometry that provides them with a shape stability aiming at maintaining the horizontal trim of the ship during the displacement of the masses taken onboard and during the movements generated by the sea or the ocean.

[0142] The elements of the craft 1 located above the waterline and in particular those located on the deck 4 have a relatively reduced height, or at least a reduced proper weight, so that the centre of gravity of the craft with its keel lowered down is very low and so that it offers a small wind resistance. The craft has no sail, mast or rigging, or any other equipment intended to use the wind force. It has hence a low radar echo due to its shape, size and to the small height of the emerged parts.

[0143] Although the craft does not use the wind for its propulsion and hence has no mast or another elevated appendix dedicated to the use of wind for propulsion, the craft can however comprise a wheelhouse 9 or a masting serving in particular to carry the radio and/or optical and/or wind generator and/or sensor pieces of equipment, as well as to place as high as possible the potential air intakes useful for certain operating modes of the drone.

[0144] The outer walls of the hull 2 and of the wheelhouse 9, preferably in their non-immersed parts, comprise access doors permitting access to the inside of some compartments of the craft 1.

[0145] The materials constituting the craft, in particular its hull 2 and its wheelhouse 9, may be chosen as a function of the needs. For example, metals can be used for the hull 2 and/or the wheelhouse 9 to keep a radar echo, or composite materials, in particular glass fibre, can be used in the opposite case.

[0146] The craft 1, which is not a reduced model of an existing ship, is herein a drone intended to perform sonar acoustic measurements, wherein the acoustic measuring systems, in particular the acoustic wave transmitting and receiving transducers, are arranged in the bulb of the keel 3. Moreover, the keel 3, in particular its bulb 6, also comprises an attitude unit that allows accurate corrections of the acoustic measurements due to the fact that this attitude unit is positioned as close as possible to the acoustic transducers.

[0147] This craft 1 is autonomous in that it comprises power-driven propulsion means 8 and an internal source of energy. It is hence not a towed device and/or a device connected by a cable to a ship or another equipment, floating or not. In a variant implementation, it can be towed.

[0148] Thanks to the shape of the hull 2 of the craft 1, the resistance to forward motion is reduced both in calm water and in rough water, and a reduction of the movements generated on the craft 1 by the agitation of the waves is obtained. The shape of the craft 1 and of its keel 3 allows improving the flow about its acoustic transducers and avoids the formation of bubbles having a masking effect at the acoustic transducers. It results therefrom a diminution of the “noises” that, in the traditional ships, cause interference to the acoustic measurements.

[0149] The drone is hence power-driven and at least one electric motor or internal combustion/chemical reaction engine or even mixed engine is used, which can operate a propeller 8 or, in variants, several propellers or one or several turbines.

[0150] The keel 3 can be lowered and lifted, preferably more or less highly lifted, so as to be able, in particular, to choose the draught of the craft. In FIG. 2, the keel 3 has been lifted and the bulb 6 remains under the hull 2, the greatest part of the height of the connection part 5 of the keel 3 having slid inside the craft hull and even, for the upper end of the connection part 5, having reached a keel-storage space 13 located inside the wheelhouse 9, as can be better seen in FIG. 5.

[0151] The wheelhouse 9 or masting hence comprises at least a hollow part that is voluminous enough to contain the part of the keel protruding from the deck or from the superstructures when the keel 3 is in lifted/upper position.

[0152] The wheelhouse 9 may have an aerodynamic shape and other functions than the only function of storing at least an upper part of the lifted keel.

[0153] In a preferred embodiment, the keel 3 is moreover dismountable and interchangeable. It is also preferred that the bulb 6 of the keel 3 is interchangeable from the keel so that the drone can be used with different configurations of acoustic transducers of various bulbs.

[0154] The hull comprises a keel well through which the keel is lowered down to the lower/exit position of the keel.

[0155] This keel well may be materialized by a hollow column adjusted to the size and shape of the keel or may correspond to a wider area for the passage of the keel, or even correspond to a wide internal compartment of the craft. In the case where the keel well is not a column adjusted to the keel, as in the example shown in the figures, it is provided that the keel passes through at least two adjusted passages arranged at different heights so as to allow an effective lifting and lowering guiding of the keel and to stabilize it along a stable vertical (or near vertical) axis, once in place and locked at the desired height. In FIGS. 3 and 5, it can be seen that the lower adjusted passage 14 corresponds to the passage of the keel 3 through the bottom of the hull 2, wherein this passage allowing the sliding of the keel 3 can be sealed. Still in FIGS. 3 and 5, it can be seen that the upper adjusted passage 15 corresponds to the passage of the keel 3 through an internal tween deck 12 of the craft 1, wherein this passage allowing the sliding of the keel 3 can potentially also be sealed.

[0156] Guiding means are hence provided between the keel and the keel well and, possibly, the keel-storage space of the wheelhouse. The craft hence comprises keel guiding means that may be a sleeve, rails, bearings, slides . . . .

[0157] Preferably, the connection part 5 of the keel 3 that is located between, at the bottom, the bulb 6 and, at the top, the upper end of the keel, has a uniform cross-section over its height and the keel well of the hull and, possibly, the keel-storage space 13 of the wheelhouse, has/have also a uniform cross-section over its/their height and that, in addition, is adjusted to that of the keel connection part 5 to allow the guiding of the keel. This adjustment between the keel, in particular the keel connection part, and the keel well and, potentially, the keel-storage space of the wheelhouse, participates to the stable fastening between both and avoids that the keel “beats” with respect to the hull. As a variant, this guiding may, as in the example shown in the figures, be limited to two guiding passages 14, 15 or more, in which are located adjustments with the keel 3.

[0158] The liftable keel is hence mechanically guided in the keel well and, potentially, in the keel-storage space of the wheelhouse, in order to recover all the efforts other than those directed parallel to the keel lifting and lowering movement, so that a link of the “sliding” type is formed between the keel and the ship.

[0159] As can be seen in FIG. 3, the keel 3 can be lifted so as to be installed at least partly in a keel-storage space 13 inside the wheelhouse 9 or the masting.

[0160] In upper position of the keel, at least partly lifted within the wheelhouse, the keel may be locked in place using magnetic locking means (not shown for the upper position). Potentially, intermediate-height positions of the keel may also be locked using magnetic locking means (not shown).

[0161] The last degree of freedom remaining, in lifting and lowering of the keel, is hence locked by magnetic locking means allowing the keel to be locked at determined heights with respect to the hull. These determined heights are at least the lowered position of the keel and the lifted position of the keel corresponding to the amplitude of maximum vertical displacement of the keel.

[0162] The magnetic locking means are consisted of functional pairs, each comprising two magnetically complementary parts able to attract each other and/or repel each other and/or become magnetically inactive as a function of commands. One of the two parts is an electromagnet and the commands are performed using electrical currents.

[0163] To simplify the figures, the magnetic locking means have been fully shown only for the locking in lowered position of the keel 3. Hence, in FIG. 3 in which the keel 3 is magnetically locked in lowered position, the magnetic locking means 11 is arranged in relation with the upper end of the connection part 5 of the keel 3 and with the tween deck 12. In FIG. 4, the magnetic locking means 11 has been unlocked to begin lifting the keel and in order to improve the visibility of the two parts 11a and 11b of the magnetic locking means 11 that have been separated. These two parts 11a and 11b form a magnetic suction cup herein arranged in relation with the adjusted passage 15 through the tween deck 12.

[0164] It is understood that a similar magnetic locking means (not shown) is implemented between the upper end of the connection part 5 of the keel 3 and the wheelhouse 9 in order to be able to lock the keel in lifted/upper position and that, for that purpose, the same part 11b can be used for locking the lowered position and the lifted position.

[0165] In variants, by way of security, manually activatable and deactivatable mechanical locking means may be additionally provided, and in particular for the upper/lifted position of the keel, these locking means being for example a pin fastening the walls of the connection part 5 and the wheelhouse 9 to each other.

[0166] The keel can also possibly be locked at intermediate heights between the two previous extreme positions, either at predetermined heights, wherein punctual locking means are installed at these predetermined heights, or at any heights. In this latter case, a vertical ferromagnetic plate is arranged along the keel well and an electromagnet arranged in the keel can circulate opposite the plate during the keel lifting and lowering operations, wherein the activation of the electromagnet causes an attraction with the plate that blocks the displacement of the keel at any desired position in height.

[0167] The locking with electromagnets may be of the “free under tension” or “closed under tension” mode, according to the embodiments.

[0168] In a simplified embodiment, the bulb remains under the hull, potentially protected within a recess of the hull, and does not pass through the keel well. In a more sophisticated embodiment, the bulb may also be lifted through the well, wherein the well is either configured to leave the passage to the bulb, or able to come in alignment with the keel connection part, for example by tilting, and to enter the projected volume of this connection part, the keel well having a shape adjusted to the volume of the keel connection part.

[0169] The lifting and the lowering of the keel through the hull and the keel well, and toward and from the keel-storage space of the wheelhouse, implements a motorization with a mechanical means (not shown) for the forced lifting: winch, hydraulic jack, rack, endless screw . . . and, possibly also for the forced lowering, and in this latter case, the height-position locking of the keel may be ensured by the mechanical means.

[0170] Preferably, by way of security, a descent stop is provided, preventing the keel from going down beyond the determined limit. This descent stop may be a wider part of the upper end of the keel, which comes into abutment against a stop placed at the lower end of the keel well or, as in the figures, arranged in relation with the passage 15 through the tween deck 12. This keel stop may be an element added at the upper end of the keel. The stop can also serve as an upper fitting bearing in lower position of the keel. The stop can support either the electromagnet(s), or magnetic parts on which the electromagnets can magnetically act by magnetic attraction or repulsion according to the embodiments. The mechanical guiding and the stops and abutments are designed in such a manner that the only forces to which the electromagnets are subjected are directed in the axis of lifting/lowering displacement of the keel.