Sailing propulsion element comprising a mast and an inflatable sail fitted with an inflatable compartment formed around the mast

Abstract

This sail propulsion element (6) comprises: a mast (8); an inflatable sail (10) internally delimiting an inflatable cavity, the sail (10) comprising an upper part, a lower part, a leading edge and a trailing edge, the sail (10) comprising different curves forming bulges; a head (12) arranged on the upper part of the sail (10); a sail receptacle (14) arranged on the lower part of the sail (10). The inflatable sail (10) comprises an inflatable compartment (22) formed around the mast (8), the compartment being inflatable independently of the inflatable cavity. Figure for the abstract: Fig 2

Description

Title of the invention: Sailing propulsion element comprising a mast and an inflatable sail provided with an inflatable compartment formed around the mast Technical field

[0001] The invention relates to a vehicle with sail propulsion and is in the field of sail propulsion or hybrid sail propulsion.

[0002] In particular, the invention relates to a sail propulsion element. Previous techniques

[0003] A sail propulsion element intended to equip a sail-powered vehicle and described in document WO 2022 / 248812 is known from the state of the art.

[0004] The sail propulsion element described in this document comprises a mast, an inflatable sail provided with a plurality of cells spaced apart by ribs made of a flexible material allowing air to pass through, at least one air duct arranged between the inside and the outside of the inflatable sail, at least one means for injecting air into the inflatable sail, a headpiece and a sail receptacle.

[0005] The lowering, consisting of lowering the sail, and the hoisting, consisting of raising the sail, of the sail propulsion element described in document WO 2022 / 248812 have proven to be improvable. Indeed, checking the correct positioning of the inflatable sail during these two operations has proven necessary.

[0006] The invention aims at better control of the lowering and hoisting of an inflatable sail. Statement of the invention

[0007] The invention relates to a sail propulsion element comprising:

[0008] a mast;

[0009] an inflatable sail internally delimiting an inflatable cavity, the sail comprising an upper part, a lower part, a leading edge and a trailing edge, the sail comprising different curves forming bulges;

[0010] a headboard arranged on the upper part of the sail; and

[0011] a sail receptacle disposed on the lower part of the sail.

[0012] The inflatable sail comprises an inflatable compartment formed around the mast, the compartment being inflatable independently of the inflatable cavity.

[0013] The inflatable compartment independently of the inflatable cavity makes it possible to prevent the leading edge of the sail from coming into contact with the mast when lowering and hoisting the inflatable sail. This prevents damage to the inflatable sail when lowering and hoisting it. A rounded shape of the sail on the leading edge side. This avoids increasing the aerodynamic drag which would load the mast when lowering and hoisting the inflatable sail.

[0014] The leading edge is the forward portion of an airfoil. The leading edge hosts the stopping point where the flow of an incident fluid separates into two.

[0015] The trailing edge is the rear part of the aerodynamic profile considered in the direction of fluid flow.

[0016] The headpiece at least partially matches the upper contour of the sail.

[0017] The sail receptacle is capable of receiving the lowered sail. It can integrate other functions such as the absorption of tension forces provided by the sail, the housing of actuators, sensors, or a control unit for the inflatable sail.

[0018] The mast can be telescopic or inextensible.

[0019] When the mast is telescopic, it is made up of different elements capable of sliding successively relative to each other to deploy or retract.

[0020] When the mast is telescopic, the head is integral with the upper element of the telescopic mast and is capable of retaining a degree of freedom in rotation around a longitudinal axis of the mast, the upper element of the mast being capable of rotating around the longitudinal axis or the head being capable of rotating around the mast.

[0021] When the mast is inextensible, the head is movable along the mast.

[0022] The telescopic or inextensible mast may be free to rotate relative to said hull. Alternatively, the mast may be fixed at least in rotation relative to said hull.

[0023] The inflatable sail is attached to the headboard so as to descend or rise at the same time as the headboard.

[0024] The headboard has sufficient rigidity to transmit various physical forces from the inflatable sail to the mast and to support the weight of the inflatable sail.

[0025] The sail rotation control unit may be configured to control the angle of the sail relative to the wind.

[0026] The control unit may also be capable of controlling the hoisting and lowering of the inflatable sail.

[0027] Advantageously, the inflatable sail comprises at least one main canvas forming said inflatable cavity and at least one secondary canvas forming at least in part the inflatable compartment.

[0028] Optionally, the inflatable sail comprises two main canvases connected to each other around their perimeter and forming said inflatable cavity.

[0029] According to a first design, said main canvas partly forms the inflatable compartment.

[0030] Optionally, the inflatable compartment forms the leading edge of the inflatable sail.

[0031] Thus, the leading edge of the inflatable sail retains its shape during the hoisting or lowering of the inflatable sail.

[0032] According to a second alternative design, the inflatable compartment is arranged in the inflatable cavity.

[0033] Optionally, the inflatable compartment is formed from a strip of fabric which extends longitudinally forming turns of fabric, the adjacent turns of fabric of said inflatable compartment being sewn together by at least one seam extending helically along said inflatable compartment.

[0034] This increases the torsional rigidity of the inflatable compartment, which reduces its deformation in the event of strong winds.

[0035] Advantageously, the inflatable compartment extends over the entire height of the inflatable sail.

[0036] Preferably, the mast extends into the inflatable cavity.

[0037] Optionally, the inflatable sail comprises a plurality of secondary canvases arranged so as to form tubular portions of the inflatable compartment, said tubular portions together forming the inflatable compartment.

[0038] Advantageously, the inflatable sail comprises a plurality of partitions defining cells each extending from the leading edge to the trailing edge, a tubular portion of the inflatable compartment being formed in each cell.

[0039] Preferably, the grammage of said secondary fabric is at least twice lower than the grammage of said main fabric.

[0040] Optionally, said main fabric has a grammage of between 50 and 300 gm 2

[0041] Optionally, said secondary fabric has a grammage of between 20 and 150 gm 2

[0042] According to a particular design, said main canvas partly forms the inflatable compartment.

[0043] Optionally, the inflatable sail comprises at least one opening opposite the mast, said opening being provided with a device for closing said opening, in particular a zipper. Said opening facilitates maintenance of the mast. Said sealing device guarantees the sealing of the inflatable compartment.

[0044] Preferably, the sail propulsion element comprises at least one first air injection device in fluid communication with the inflatable compartment, and at least one second air injection device in fluid communication with said inflatable cavity.

[0045] Said first air injection device may comprise a fan.

[0046] Said second air injection device may comprise a fan.

[0047] The sail propulsion element may comprise at least one means for detecting the pressure in the inflatable compartment and at least one means for detecting the pressure in the inflatable cavity.

[0048] The control unit may be capable of controlling the operation of the air injection devices as a function of signals from said pressure detector means.

[0049] The control unit may also be capable of controlling the hoisting and lowering of the inflatable sail as a function of signals from said pressure detector means.

[0050] The present invention also relates to a vehicle with sail propulsion or hybrid propulsion comprising at least one hull, at least one sail propulsion element as defined above, the mast of said sail propulsion element being integral with said hull, the inflatable sail of said sail propulsion element being free to rotate.

[0051] The present invention also relates to a method for hoisting an inflatable sail of a sail propulsion element as defined above, comprising at least maintaining a nominal air pressure in the inflatable compartment during hoisting of the inflatable sail.

[0052] The hoisting method can be implemented so that the air pressure inside said inflatable cavity is strictly lower than the air pressure in the inflatable compartment when hoisting the inflatable sail.

[0053] The present invention also relates to a method for lowering an inflatable sail of a sail propulsion element as defined above, comprising at least maintaining a nominal air pressure in the inflatable compartment during the lowering of the inflatable sail.

[0054] The lowering method can be implemented so that the air pressure inside said inflatable cavity is strictly lower than the air pressure in the inflatable compartment when the inflatable sail is lowered. Brief description of the drawings

[0055] The present invention will be better understood upon studying the detailed description of embodiments, taken as non-limiting examples and illustrated by the appended drawings in which:

[0056] [Fig-1] is a front view of a sail-powered vehicle according to a first exemplary embodiment of the invention;

[0057] [Fig.2] is a side view of the inflatable sail of the sail-powered vehicle of [Fig.l];

[0058] [Fig.3] is a cross-sectional view of [Fig.2];

[0059] [Fig.4] is a detailed view in longitudinal section of [Fig.2];

[0060] [Fig.5] is a schematic representation of a hoisting method according to the invention;

[0061] [Fig.6] is a schematic representation of a lowering method according to the invention;

[0062] [Fig.7] is a view similar to that of [Fig.2] according to a second example of realization of the invention; and

[0063] [Fig.8] is a cross-sectional view of [Fig.7]. Detailed description

[0064] [Fig.l] illustrates a sail-powered vehicle 2, for example a sailboat or a ship, comprising a hull 4 and a sail-powered element 6. Alternatively, the sail-powered vehicle 2 could comprise several hulls 4, for example when the sail-powered vehicle 2 is a catamaran or a trimaran.

[0065] The sail propulsion element 6 comprises a self-supporting mast 8 secured to the hull 4 by a support (not shown), an inflatable sail 10, a head 12 and a sail receptacle 14.

[0066] The inflatable sail 10 internally delimits an inflatable cavity. The inflatable sail 10 here comprises two main canvases 16 connected to each other around their periphery so that the mast 8 extends longitudinally between the two main canvases 16. The inflatable sail 10 comprises an upper part, a lower part, a leading edge and a trailing edge.

[0067] The head 12 is arranged on the upper part of the inflatable sail 10, the sail receptacle 14 being arranged on the lower part of the inflatable sail 10. The head 12 is supported by the mast 8. The head 12 is here fixed to the upper end of the mast 8. The sail receptacle 14 is fixed to the support.

[0068] The sail receptacle 14 is fixed to the support. The sail receptacle 14 extends from the leading edge to the trailing edge. The sail receptacle 14 is intended to receive all or part of the inflatable sail 10 when it is lowered.

[0069] The head 12 is movable relative to the sail receptacle 14 which is fixed. The mast 8 is telescopic and made up of different elements which slide successively against each other to deploy or retract. The head 12 is integral with the last element of the mast 8. Alternatively, the mast 8 could be inextensible, the head 12 then being movable along the mast 8. In another alternative, it could also be possible to combine a telescopic mast 8 and a head 12 which slides along this telescopic mast 8.

[0070] The inflatable sail 10 is made free to rotate relative to the hull 4 of the sail-powered vehicle 2 by any suitable means. In particular, the sail-powered element 6 comprises a control unit 17 (shown schematically) of the inflatable sail 10 capable of modifying the orientation of the inflatable sail 10 relative to the hull 4 of the sail-powered vehicle 2 in order to optimize or regulate the aerodynamic thrust generated by the inflatable sail 10.

[0071] Each of the two main canvases 16 is, for example, made of a material, in particular textile, coated to meet conditions of mechanical resistance, sealing, and protection against fire and UV radiation.

[0072] The two main canvases 16 connected together form a closed inflatable cavity. The inflatable sail 10 comprises a plurality of partitions 18 made of a flexible material and each extending at least into the inflatable cavity from the leading edge to the trailing edge. The partitions 18 delimit in the inflatable sail 10 a plurality of cells 20 in the spanwise direction of the inflatable sail 10. The partitions 18 are fixed to the main canvases, for example by sewing, welding or gluing, and give the inflatable sail 10 different curves forming bulges. Each partition 18 is made of a permeable material so as to allow air to circulate through the partition 18 in question.

[0073] The inflatable sail 10 here has a profile which remains permanently symmetrical when it is inflated, and this independently of the movement of the sail-powered vehicle 2, the orientation of the inflatable sail 10, the direction and intensity of the wind. Alternatively, an asymmetrical profile of the inflatable sail 10 could be provided when it is inflated.

[0074] As illustrated more visibly in Figures 2 and 3, the inflatable sail 10 further comprises an inflatable compartment 22 formed around the mast 8. The inflatable compartment 22 is located inside the inflatable cavity. The inflatable compartment 22 is watertight and can be inflated independently of the inflatable cavity.

[0075] The sail propulsion element 6 comprises a first air injection device 24 (shown schematically) in particular reversible, for example a reversible fan, mounted on the sail receptacle 14 and in fluid communication with the inflatable compartment 22. The first air injection device 24 is capable of injecting air into the inflatable compartment 22. The first air injection device 24 does not inject air into the inflatable cavity.

[0076] The sail propulsion element 6 comprises a second lower air injection device 26a (shown schematically) in particular reversible, for example a reversible fan, mounted on the sail receptacle 14 and in fluid communication with the inflatable cavity, and here further comprises a second upper air injection device 26b, for example a fan, mounted on the head 12 and in fluid communication with the inflatable cavity. The second lower and upper air injection devices 26a, 26b do not inject air into the inflatable compartment 22.

[0077] The sail propulsion element 6 comprises a means (not shown) for detecting the pressure in the inflatable compartment 22, and a means (not shown) for detecting the pressure in the inflatable cavity.

[0078] The control unit 17 is capable of controlling the operation of the first air injection device 24 and the second lower and upper air injection devices 26a, 26b as a function of signals from the means for detecting the pressure in the inflatable compartment 22 and in the inflatable cavity. The control unit 17 is also capable of controlling the hoisting and lowering of the inflatable sail 10 as a function of signals from the means for detecting the pressure in the inflatable compartment 22 and in the inflatable cavity.

[0079] The inflatable compartment 22 extends over the entire height of the inflatable sail 10, that is to say from the sail receptacle 14 to the head 12.

[0080] The inflatable compartment 22 comprises an elongated outer envelope which is formed from a plurality of secondary fabrics 28.

[0081] The secondary canvases 28 separate the inflatable compartment 22 from the inflatable cavity inside the inflatable sail, the inflatable cavity surrounding the inflatable compartment 22.

[0082] When the inflatable sail 10 is inflated, that is to say when the inflatable compartment 22 and the inflatable cavity are inflated, the secondary canvases 28 remain at a distance from the mast 8 and the main canvases 16.

[0083] The inflatable compartment 22 being arranged in the inflatable cavity, the secondary fabrics 28 require a lighter coating than the main fabrics 16.

[0084] Each secondary canvas 28 is, for example, made of a material, in particular textile, coated to meet conditions of mechanical resistance, sealing, and fire protection.

[0085] The weight of each secondary fabric 28 can thus be at least twice lower than the weight of each main fabric 16. For example, each main fabric 16 has a weight of between 50 and 300 g.m2, each secondary fabric 28 having a weight of between 20 and 150 gm2.

[0086] With reference to [Fig. 4], the partitions 18 delimiting in the inflatable sail 10 the plurality of cells 20 each extend in the inflatable cavity and in the inflatable compartment 22 from the leading edge to the trailing edge. The secondary canvases 28 are arranged so as to form, in each cell 20, a tubular portion 30 of the external envelope of the inflatable compartment 22. The compartment inflatable 22, in particular its external envelope, is formed from all of the tubular portions 30.

[0087] The secondary canvases 28 are fixed to the partitions 18 of the inflatable sail 10, for example by sewing, welding or gluing. Thus, each tubular portion 30 of the external envelope of the inflatable compartment 22 is fixed, in particular sewn, on either side to two successive partitions 18 of the inflatable sail 10. The inflatable compartment 22 is not fixed to the main canvases 16.

[0088] More precisely, the secondary fabrics 28 are arranged so that each tubular portion 30 of the envelope of the inflatable compartment 22 is formed of a strip of fabric which extends longitudinally, forming turns of fabric, the longitudinal axis corresponding to the longitudinal direction of the mast 8. The adjacent turns of fabric of each tubular portion 30 are sewn together by at least one seam 32 extending helically along the tubular portion 30 in question.

[0089] In the example shown, the outer casing of the inflatable compartment 22 is conical with its larger diameter end on the side of the sail receptacle 14. Alternatively, the outer casing of the inflatable compartment 22 could be cylindrical. As a variant, some tubular portions 30 of the outer casing of the inflatable compartment 22 could be cylindrical and others conical.

[0090] [Fig.5] schematically illustrates a method of hoisting the inflatable sail 10 of the sail propulsion element 6.

[0091] In a step 34, we begin by injecting air into the inflatable compartment 22. For example, the first air injection device 24 injects air into the inflatable compartment 22.

[0092] A step 36 of hoisting the inflatable sail 10 is then carried out by continuing to inject air into the inflatable compartment 22 so as to maintain a nominal air pressure therein during the hoisting of the inflatable sail 10. The nominal pressure corresponds to a pressure sufficient to maintain the inflatable cavity in shape without risk of collapse. The hoisting of the inflatable sail 10 is controlled by the control unit 17 and is obtained by the deployment of the mast 8 which in the illustrated embodiment is telescopic. During the hoisting of the inflatable sail 10, the head 12 is movable relative to the fixed sail receptacle 14.

[0093] Step 36 of hoisting the inflatable sail 10 is carried out so that the air in the inflatable cavity is at a pressure strictly lower than the pressure of the air in the inflatable compartment 22 when hoisting the inflatable sail 10, preferably at least two times lower, and more preferably at least five times lower than the pressure of the air in the inflatable compartment 22.

[0094] When the inflatable sail 10 is fully hoisted, a step 38 of injecting air into the inflatable cavity is carried out so that the air in the inflatable cavity is at the nominal pressure. For example, the second lower and upper air injection devices 26a, 26b perform air injection into the inflatable cavity.

[0095] [Fig.6] schematically illustrates a method of lowering the inflatable sail 10 of the sail propulsion element 6.

[0096] In a step 40, air is extracted from the inflatable cavity. For example, each second lower and upper air injection device 26a, 26b is reversible so as to be able to suck air from the inflatable cavity. Thus, each second lower and upper air injection device 26a, 26b can extract air from the inflatable cavity in step 40. Alternatively, each second lower and upper air injection device 26a, 26b is able to let air escape from the inflatable cavity.

[0097] When the air pressure in the inflatable cavity is at a pressure strictly lower than the air pressure in the inflatable compartment 22, preferably at least two times lower, and more preferably at least five times lower than the air pressure in the inflatable compartment 22, a step 42 of lowering the inflatable sail 10 is carried out while maintaining the nominal pressure in the inflatable compartment 22 during the lowering of the inflatable sail 10. The lowering of the inflatable sail 10 is controlled by the control unit 17 and is obtained by the retraction of the mast 8. During the lowering of the inflatable sail 10, the head 12 is movable relative to the fixed sail receptacle 14.

[0098] When the inflatable sail 10 is lowered, the injection of air into the inflatable compartment 22 is reduced, or the injection of air into the inflatable compartment 22 is cut off, or air is extracted from the inflatable cavity, so as to maintain the nominal pressure in the inflatable compartment 22. For example, the first air injection device 24 is reversible in order to be able to suck air from the inflatable compartment 22.

[0099] When the inflatable sail 10 is completely lowered, a step 44 is carried out to extract the air contained in the inflatable compartment 22 and in the inflatable cavity in order to press the inflatable sail 10 against the sail receptacle 14.

[0100] The embodiment illustrated in Figures 7 and 8 differs from the first embodiment in that the two main canvases 16 partly form the inflatable compartment 22. More precisely, the leading edge of the inflatable sail 10 is delimited by the inflatable compartment 22.

[0101] The two main canvases 16 are connected here to the inflatable compartment 22 at the leading edge.

[0102] The secondary canvases 28 of the inflatable compartment 22 are here fixed to the main canvases 16. More precisely, the secondary canvases 28 forming each tubular portion 30 of the external envelope of the inflatable compartment 22 are fixed to two successive partitions 18 and to the two main canvases 16 of the inflatable sail 10, the secondary canvases 28 extending in an arc of a circle.

[0103] The secondary canvases 28 separate inside the inflatable sail 10 the inflatable compartment 22 from the inflatable cavity, the inflatable compartment 22 being adjacent to the inflatable cavity.

Claims

Claims

1. Sailing propulsion element (6) comprising: - a mast (8); - an inflatable sail (10) internally delimiting an inflatable cavity, the sail (10) comprising an upper part, a lower part, a leading edge and a trailing edge, the sail (10) comprising different curves forming bulges; - a head (12) arranged on the upper part of the sail (10); and - a sail receptacle (14) arranged on the lower part of the sail (10); characterized in that the inflatable sail (10) comprises an inflatable compartment (22) formed around the mast (8), the compartment (22) being inflatable independently of the inflatable cavity.

2. Sail propulsion element (6) according to claim 1, in which the inflatable sail (10) comprises at least one main canvas (16) forming said inflatable cavity and at least one secondary canvas (28) forming at least in part the inflatable compartment (22).

3. Sail propulsion element (6) according to claim 2, in which said main fabric (16) partly forms the inflatable compartment (22).

4. A sail propulsion element (6) according to any one of claims 1 to 3, wherein the inflatable compartment (22) forms the leading edge of the inflatable sail (10).

5. A sail propulsion element (6) according to claim 1 or 2, wherein the inflatable compartment (22) is arranged in the inflatable cavity.

6. A sail propulsion element (6) according to claim 5, wherein the inflatable compartment (22) is formed from a strip of fabric which extends longitudinally forming turns of fabric, the adjacent turns of fabric of said inflatable compartment (22) being sewn together by at least one seam (32) extending helically along said inflatable compartment (22).

7. Sail propulsion element (6) according to any one of claims 1 to 6, in which the inflatable compartment (22) extends over the entire height of the inflatable sail (10).

8. A sail propulsion element (6) according to any one of claims 2 to 7, wherein the inflatable sail (10) comprises a plurality of secondary canvases (28) arranged to form tubular portions (30) of the inflatable compartment (22), said tubular portions (30) together forming the inflatable compartment (22).

9. A sail propulsion element (6) according to claim 8, wherein the inflatable sail (10) comprises a plurality of partitions (18) defining cells (20) each extending from the leading edge to the trailing edge, a tubular portion (30) of the inflatable compartment (22) being formed in each cell (20).

10. Sail propulsion element (6) according to claim 2 or according to any one of claims 3 to 9 dependent at least on claim 2, in which the grammage of said secondary fabric (28) is at least twice lower than the grammage of said main fabric (16).

11. Sail propulsion element (6) according to any one of claims 1 to 10, comprising at least one first air injection device (24) in fluid communication with the inflatable compartment (22), and at least one second air injection device (26a, 26b) in fluid communication with said inflatable cavity.

12. Sailing propulsion element (6) according to claim 11, comprising at least one means for detecting the pressure in the inflatable compartment (22), at least one means for detecting the pressure in the inflatable cavity, and a control unit (17) capable of controlling the operation of the air injection devices (24, 26a, 26b) as a function of signals from said pressure detecting means.

13. Vehicle (2) with sail propulsion or hybrid propulsion comprising at least one hull (4), at least one sail propulsion element (6) according to any one of claims 1 to 12, the mast (8) of said sail propulsion element (6) being integral with said hull (4), the inflatable sail (10) of said sail propulsion element (6) being free to rotate

14. A method of hoisting an inflatable sail (10) of a sail propulsion element (6) according to any one of claims 1 to 12, comprising at least maintaining a nominal pressure of air (36) in the inflatable compartment (22) when hoisting the inflatable sail (10).

15. A hoisting method according to claim 14, wherein the air pressure inside said inflatable cavity is strictly lower than the air pressure in the inflatable compartment (22) when hoisting the inflatable sail (10).

16. Method for lowering an inflatable sail (10) of a sail propulsion element (6) according to any one of claims 1 to 12, comprising at least maintaining a nominal air pressure (42) in the inflatable compartment (22) during the lowering of the inflatable sail (10).

17. A method of lowering according to claim 16, wherein the air pressure inside said inflatable cavity is strictly lower than the air pressure in the inflatable compartment (22) when lowering the inflatable sail (10).

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