EP3953252A1

EP3953252A1 - Rotary wing in the field of aircraft

Info

Publication number: EP3953252A1
Application number: EP20715104.4A
Authority: EP
Inventors: Guy Valembois
Original assignee: Conseil et Technique SAS
Current assignee: Conseil et Technique SAS
Priority date: 2019-04-09
Filing date: 2020-04-06
Publication date: 2022-02-16
Also published as: WO2020207955A1

Abstract

The present invention relates to a rotary wing in the field of aircraft, comprising a central part (1) formed by an aerodynamic shape that revolves in relation to an axis (XX'), blades (3) arranged on the periphery of the central part (1) and extending radially in relation to the axis (XX') and a shaft (2) that is coaxial to the axis (XX') and provides the rotational movement of the assembly formed by the central part (1) and the blades (3). The central part (1) of the rotary wing has a lenticular shape with a curvature of the upper part (10) that is greater than that of the lower part (11) in order to form, respectively, a suction surface and a pressure surface, the central part (1) forming a bearing aerodynamic volume.

Description

Title of the invention: Rotary wing in the field of aircraft

[0001] The present invention relates to a wing in the field of aircraft, and more particularly a rotary wing in particular for drones, helicopters, and airplanes.

[0002] In the state of the art, document US Pat. No. 3,331,444 is known, which relates to a fairing for a helicopter, the blades of which are mounted at a central part at the level of a cowl, said blades being driven in rotation.

[0003] Document US 7510 377 describes a rotor plane, comprising a pair of blades driven in rotation by the setting in rotation of a rotational central housing, comprising two portions linked together.

[0004] Document EP 0 680 876 also discloses a faired anti-torque multi-blade rotor with floating blades, for rotary-wing aircraft, in particular helicopters.

[0005] In document US Pat. No. 3,640,485, an aircraft of the helicopter type is described comprising a toroidal annular compartment intended to receive

passengers, and in the center of which is a central circular compartment in the form of a dome.

[0006] None of the devices described in the state of the art, however, is capable of ensuring optimum lift during horizontal movement of the aircraft.

[0007] The rotary airfoil according to the invention seeks to resolve the problem of lift in horizontal displacement of known devices.

[0008] The kinematics of rotation of a rotary wing with fixed blades, for drones, mobile, for helicopters, imposes a maximum speed relative to the air at the end of the blade.

[0009] The lift of an airfoil is directly proportional to the speed relative to air squared.

[0010] The effective part of a rotor is therefore constituted by the end of its blades. The rotary airfoil according to the invention is characterized in that it comprises, at least, a central part consisting of an aerodynamic shape and of revolution with respect to an axis, blades arranged at the periphery of said central part and extending radially with respect to said axis, and a shaft coaxial with said axis and ensuring the rotational movement of the assembly consisting of said central part and said blades.

[0012] According to the invention, the geometry of the blades is limited to their effective part, to allow the use of the central part which consists of an aerodynamic volume bearing during the horizontal movement of the aircraft.

Still according to the invention, the central part has a lenticular shape, with a curvature of the upper part greater than that of the lower part, to respectively form an upper surface and a lower surface and the lenticular central part forms an aerodynamic volume wearing.

[0014] Advantageously, the blades can be provided with flaps for

increase their efficiency at different rotation speeds, partially or fully retractable depending on the flight situations, mobile as in the case of a helicopter rotor.

The central part has a significant thickness in its center to allow the curvature of the upper surface, this creates a volume which can be used judiciously to place a motor within it, which can create the rotational movement. The central part is load-bearing in horizontal flight, this lift can be increased by the incidence of this central part.

[0016] Preferably, said blades may each be provided with a partially or fully retractable camber flap depending on the flight situations, to increase their efficiency.

In a particularly advantageous embodiment, said central part has a generally triangular geometry, each of the vertices of which is extended by a blade, and, in each of the transition zones between a blade and said central part, its peripheral edge presents a generally curved profile. [0018] Also, it is conceivable that the rotary airfoil further comprises a peripheral hooping of the blades.

In this case, the rotary airfoil can advantageously have the geometry of an axial turbine, the peripheral hooping and the blades extending the lenticular shape of said rotary airfoil, by having an internal shape capable of positively guiding the flow of air passing through it, and a peripheral outer shape capable of constituting the outer edge of the rotary airfoil in the form of a lens.

[0020] The invention also relates to a double rotor comprising an upper rotary airfoil and a lower rotary airfoil associated with each other, said two rotary airfoils each comprising a central part on which are fixed the circled blades a peripheral hooping, the upper part of said double rotor being of greater curvature than that of its lower part in order to form an upper surface and an lower surface respectively, said double rotor being of lenticular shape.

Said two rotary wings can preferably be associated with one another through a central support having an annular portion from which extends a plate, said annular portion being sandwiched between the two wings rotating, a drive shaft being integrally positioned substantially in the center of the annular portion, and being connected to motor means, for the rotation of said two rotary wings.

These motor means are advantageously capable of imposing

reverse rotational movements to each of the two upper and lower rotary airfoils.

[0023] The concept could be advantageously used in the definition of a

aircraft comprising one or more of these rotary wings or one or more of these double rotors.

[0024] The use of this type of rotor may allow vertical flight by the lift effect of the blades, then a horizontal speed setting which makes it possible to give lift to the aircraft by the lift effect of the central part , even a cancellation of the rotational speed of the rotor to use, at a certain speed, only the lift effect of the central part.

The setting in horizontal speed can be induced by a means

complementary consisting, for example but not limited to, of at least one propeller propeller or a traction propeller.

[0026] The advantages and characteristics of the rotary airfoil according to the invention will emerge more clearly from the following description which relates to the accompanying drawing, which represents several non-limiting embodiments thereof.

[0027] In the accompanying drawing:

[0028] [Fig.1] shows a schematic plan view of a first mode of

realization of a rotary wing according to the invention;

[0029] [Fig.2] shows a side view of the same rotary airfoil;

[0030] [Fig.2] is a schematic perspective view of a low horizontal speed vehicle equipped with four rotary wings according to the first embodiment, as illustrated in Figures 1 and 2;

[0031] [Fig.4a] and [Fig.4b] each represent a schematic perspective view of a medium horizontal speed vehicle each equipped with four rotary wings as illustrated in Figures 1 and 2, while Figure 4c shows a detail of Figure 4b;

[0032] [Fig.5a] shows a schematic front view of a large vehicle

horizontal speed equipped with four rotary wings illustrated in Figures 1 and 2, while

[0033] [Fig.5b] and [Fig.5c] each show a detail of said vehicle according to a

particular and non-limiting example of embodiment;

[0034] [Fig.6a] shows a schematic perspective view of a second particular embodiment of a rotary airfoil according to the invention, comprising blades equipped with camber flaps, while

[0035] [Fig.6b] illustrates a sectional view of the rotary airfoil of Figure 6a, the central part of the rotary airfoil incorporating a motor; [0036] [Fig.6c] and [Fig.6d] illustrating a detail of the rotary wing of Figure 6a, namely a blade equipped with a camber flap, the latter being in the retracted position during take-off ([Fig.6d]) and in the deployed position in a flight situation ([Fig.6c]);

[0037] [Fig.7] schematically illustrates an aircraft equipped with three rotary wings according to the second embodiment of Figure 6a;

[0038] [Fig.8a], [Fig.8b] and [Fig.8c] illustrate, schematically, various views of a third embodiment of the rotary airfoil of the invention, the central part of which has a globally triangular shape, the points of the triangle each converging towards a blade;

[0039] [Fig.9] shows, schematically and in perspective, a fourth embodiment of a rotary airfoil according to the invention;

[0040] [Fig.10] shows, schematically and in perspective, a fifth embodiment of a rotary airfoil according to the invention;

[0041] [Fig.1 1] shows, schematically and in perspective, a sixth embodiment of a rotary airfoil according to the invention;

[0042] [Fig.12a] and [Fig.12b] schematically illustrate, respectively, an exploded perspective view and a side view, of a seventh embodiment of a rotary airfoil according to the invention.

Figures 1 and 2 can be seen a first embodiment, no

limitative, of a rotary airfoil 100 according to the invention.

This rotary airfoil 100 comprises a central part 1 of the shape

Lenticular and generally circular, having, visible in Figure 2, an upper face 10, or extrados, of greater curvature than that of its lower face 11, or intrados.

The central part 1 is mounted at the end of a drive shaft 2, visible in Figure 2, of axis XX ’constituting the axis of revolution of the solid form formed by the central part 1.

On the other hand, the central part 1 of the rotary airfoil 100 protrude radially from the axis XX ', the blades 3, the number of which is advantageously between three and ten depending on the design and the embodiment of said rotary airfoil.

The central part 1 of the rotary airfoil 100 of the invention thus preferably has a significant thickness at its center to allow the curvature of the upper surface 10, thus creating a sufficient volume to be able to be used judiciously in order to positioning, within it, a motor M, illustrated in particular in FIG. 6b in the context of a second embodiment of the invention.

This motor M is capable of creating the rotational movement of the rotary airfoil 100 of the invention through the drive shaft 2.

The present invention also relates to an aircraft comprising at least one rotary wing 100 according to this first embodiment of the invention.

Thus, for example, and with reference to FIG. 3, the invention also relates to an aircraft at low horizontal speed 200, of the drone type, advantageously incorporating a plurality of such rotary wings 100 illustrated in the figures 1 and 2. In this case, said low horizontal speed aircraft 200 comprises four rotary wings 100, as well as, optionally, additional means for inducing horizontal speeding, such as at least one traction propeller 4 or a propeller.

[0051] The rotary wings 100 of the invention here provide control over roll, yaw and angle of attack.

Referring to Figures 4a to 4c, the invention also relates to an aircraft at medium horizontal speed 201 a, 201 b comprising, preferably, several rotary wings 100 according to the invention, for example four rotary wings 100, as well that, advantageously, at least one traction propeller 41 a, 41 b, respectively, or a propulsion propeller, not shown.

On the aircraft 201a at medium horizontal speed of Figure 4a, the rotary wings 100 control the roll and yaw while the incidence is adjusted by horizontal movement of said rotary wings 100 around the 'Y axis. On the aircraft 201b at medium horizontal speed of FIG. 4b, the rotary wings 100 ensure control of the roll and the angle of attack is adjusted by movement of flaps 61, 62, 63, 64, in particular a flap fin 64 in a fin 6. It is also possible to consider integrating roll flaps 61, 62 and an incidence flap 63 in the horizontal plane of a tail 5.

Referring now to Figures 5a to 5c, the present invention also relates to an aircraft at high horizontal speed, 202a, 202b, equipped with a fin 7.

As with the previous examples, the high-speed aircraft

horizontal 202a, 202b advantageously comprises four rotary wings 100 according to the first embodiment of the present invention, two rotary wings 100 at the front and two rotary wings 100 at the rear. Flaps 81, 82, 83 are preferably integrated to control the roll, and the blades 3 can be retractable.

[0057] On the horizontal high-speed aircraft 202b can be

advantageously integrated reactors, one of which 9 is visible in Figure 5b.

[0058] Figures 6a to 6d illustrate a second embodiment,

particularly preferred, of a rotary airfoil 101 according to the present invention.

The characteristics of this rotary airfoil 101 are similar to those of the rotary airfoil 100 described above, in particular with regard to the presence of a central part 1 of lenticular and generally circular shape at the periphery of which are positioned blades 3, while a shaft 2 makes it possible to drive said rotary airfoil 101 in rotation by the action of a motor M, visible in FIG. 6b.

[0060] In this embodiment, the blades 3 are provided with camber flaps 31, in order to increase the efficiency of said blades at different rotational speeds.

These camber flaps 31 are partially or totally retractable, and this depending on the flight situations.

In particular, the camber flap 31 of a blade 3 may be in

retracted position during take-off, as shown in Figure 6d, when the speed of rotation W of the rotary wing 101 increases with a view to vertical take-off, the horizontal speed V then being zero or almost zero (V0), and in the deployed position in the flight situation, as visible in FIG. 6c, when the speed of rotation W of the rotary airfoil 101 is zero and the horizontal speed increases.

[0063] Figure 7 shows an aircraft 203 equipped with a plurality of such rotary wings 101, in this case three rotary wings 101, as well

that possibly a propeller, the blades 3 of said rotary wings 101 each being provided with a camber flap 31.

A third embodiment of the rotary airfoil according to the invention is illustrated in Figures 8a to 8c.

In this embodiment, the rotary airfoil 102 has a particularly optimized shape, based on:

- a central part 1 of shape presenting a significant lift in the event of incidence setting without the need for rotation;

- Blades 3 making it possible to create lift during rotation without relative translational movement;

- Mechanisms to manage the incidence of the blades 3 relative to the horizontal plane of the rotor, or even to retract the blades 3.

Thus, the rotary airfoil 102 of FIGS. 8a to 8c has a lens of generally triangular shape, the points of the triangle of which each converge towards a blade 3 of said airfoil 102.

In this embodiment, the transition between the central lens 1 and the blades 3 is done continuously; in other words, the perimeter of the triangular central part 1 of the rotary airfoil 102 is extended, without interruption or discontinuities, at the points of the triangle towards three blades 3, in order to optimize the aerodynamic flows for all the use case.

In Figures 8a to 8c, the blades 3 not provided with camber flaps are shown. However, it is obviously conceivable that the rotary airfoil 102 of substantially triangular shape comprises blades 3 similar to those of the rotary airfoil 101 and illustrated in FIGS. 6a to 6d, that is to say each provided with a camber flap 31. The fourth embodiment of the rotary airfoil 103 of the invention, illustrated in Figure 9, is of particular interest in predominantly vertical use, in a drone-type aircraft, where the lenticular central part 1 simply serves in pushing the blades 3 back to a diameter where they are really effective.

In this way, the blade root 32 is integral with the central part 1

lenticular rigidly, which substantially reduces the phenomenon of deformation due to lifting forces.

These strengths and rigidities of the pair of the lenticular central part 1 and blades 3 make it possible to have a much larger number of chord blades than in the case of a conventional drone blade.

In fact, in the case of a conventional drone blade solution, the

convergence of the blades requiring their attachment to a central hub limits the potential number of blades.

The resistance of the central part 1 of the rotary airfoil 103, associated with the large perimeter of said central part 1, allows a multiplication of the blades on the periphery thereof, which correspondingly increases the lift of the rotary airfoil 103 thus constituted.

In a fifth embodiment, illustrated in FIG. 10, the rotary airfoil 104 comprises a peripheral hoop 12 of the blades 3.

[0075] The presence of such a peripheral strapping 12 is particularly

advantageous.

On the one hand, this peripheral strapping 12 allows an increase in the

rigidity of the blades 3, whether in bending or in torsion. On the other hand, said strapping 12 results in a limitation of the transverse flow between the lower surface and the upper surface of the blades 3, which resulted in a decrease in

performance of said blades 3, due to the vortex effect at the end of the blade. Finally, by means of the peripheral strapping 12, the dangerousness of the blades 3 is reduced in the event of a collision.

In Figure 10 is shown a rotary airfoil similar to that of the fourth embodiment and illustrated in Figure 9, with the difference that the rotary airfoil 104 of FIG. 10 is completed by a peripheral hooping. However, it is also conceivable that the airfoils

turntables 100, 101, 102 of the first, second and third embodiments, respectively, are equipped with a peripheral strapping.

In a sixth embodiment, shown in Figure 1 1, the strapping

peripheral 13 is used to extend the lenticular shape of the rotary airfoil 105, by having an internal shape capable of guiding

positively the flow of air passing through it, and a peripheral outer shape capable of constituting the outer edge of the rotary airfoil 105 in the form of a lens.

In this case, the peripheral rim 13, as well as the blades 3 participate in the lenticular shape and said blades 3 are integrated into the lens in the form of a rotor having the geometry of an axial turbine, particularly effective to generate the air flow necessary for the lift by rotation of the rotary airfoil 105, and whose general lenticular shape is suitable for allowing horizontal hovering flight.

Two rotary wings 106a and 106b according to the invention, shown in Figures 12a and 12b, can be combined in a double rotor 106, in another particular embodiment of the present invention.

These upper 106a and lower 106b rotary wings comprise,

each, a central part 1 a, 1 b respectively, on which are fixed the blades 3a, 3b, and a peripheral hoop 13a, 13b.

Said two rotary wings 106a and 106b are associated with one another through a central support 14 having an annular-shaped portion 141 from which extends a plate 142, said annular portion 141 being taken in. sandwich between the two rotary wings 106a and 106b.

[0083] The plate 142 makes it possible to make the connection between the annular portion 141 and the structure of the aircraft which is capable of being fitted with the double rotor 106.

Substantially at the center of the annular portion 141, and secured thereto, is positioned a drive shaft 143 for the rotation, through motor means, of the upper 106a and lower 106b rotary airfoils. Preferably, said motor means, not shown, are capable of imposing reverse rotational movements on each of the two upper 106a and lower 106b rotary airfoils.

Finally, a double rotor 106 is obtained, the upper face of which, or

the upper surface, is of greater curvature than that of its lower surface, or lower surface, as is more particularly visible in the attached FIG. 12b.

[0087] The presence of an upper rotary airfoil 106a and an airfoil

lower rotary 106b, preferably each driven by an independent motor means, secures an aircraft equipped with double rotors 106, in the event of failure of one of the rotary wings 106a, 106b. In this hypothesis, the second non-defective rotary wing of the double rotor continues to operate.

In this embodiment of the double rotor 106, the peripheral straps 13a, 13b of the upper 106a and lower 106 rotary airfoils, as well as the shape of the support 14, makes it possible to materialize an overall lenticular shape to allow horizontal lift.

The flow allowing the vertical lift is guided by a cylindrical pipe formed by the interior shapes of the peripheral straps 13a, 13b and of the support 14.

The integration of the rotors or rotary wings of the invention on an aircraft advantageously makes it possible to combine the functions of a drone and those of an airplane, by allowing vertical take-off by the lift effect of the blades, then a setting in horizontal speed which makes it possible to give, through the central part 1 of said rotor, lift to the aircraft, or even a cancellation of the speed of rotation of the rotary airfoil so as not to use, at a certain horizontal speed , that the lift effect of said central part.

The horizontal speed setting may optionally be induced by at least one additional means such as a propeller or traction propeller.

Claims

[Claim 1] [Rotary wing (100, 101, 102, 103, 104, 105) in the field of aircraft, characterized in that it comprises, at least, a central part (1) consisting of an aerodynamic shape and of revolution with respect to an axis (XX '), blades (3) arranged at the periphery of said central part (1) and extending radially with respect to said axis (XX'), and a shaft

(2) coaxial with said axis (XX ’) and ensuring the rotational movement of

the assembly consisting of said central part (1) and said blades (3) and in that the central part (1) has a lenticular shape, with a curvature of the upper part (10) greater than that of the lower part (1 1), to respectively form an upper surface and a lower surface, said central part (1) forming a bearing aerodynamic volume.

[Claim 2] Rotary airfoil (100, 101, 102, 103, 104, 105) according to claim 1, characterized in that a motor (M) is positioned within said central portion (1) of lenticular shape.

[Claim 3] Rotary airfoil (101) according to any of

preceding claims, characterized in that each of said blades

(3) is equipped with a partially or fully retractable camber flap (31).

[Claim 4] Rotary airfoil (102) according to any one of

preceding claims, characterized in that said central part (1) has a generally triangular geometry, each of the vertices of which is extended by a blade (3), and in that in each of the transition zones between a blade (3) and said central part (1), its peripheral edge has a generally curved profile.

[Claim 5] Rotary airfoil (104, 105) according to any one of the preceding claims, characterized in that it further comprises a peripheral hooping (12, 13) of the blades (3).

[Claim 6] A rotary wing (105) according to claim 1 and

preceding claim, characterized in that it has the geometry of an axial turbine, the peripheral ring (13) and the blades (3) extending the lenticular shape of said rotary airfoil (105), having an internal shape capable of guiding positively the flow of air passing through it, and a peripheral outer shape capable of constituting the outer edge of the rotary airfoil (105) in the form of a lens.

[Claim 7] Double rotor (106) characterized in that it comprises an upper rotary airfoil (106a) and a lower rotary airfoil (106b) associated with each other, said two rotary airfoils (106a, 106b) comprising , each, a central part (1 a, 1 b) on which are fixed the blades (3a, 3b) surrounded by a peripheral hooping (13a, 13b), the upper part (106a) of said double rotor (106) being of curvature greater than that of its lower part (106b) to form an upper surface and an lower surface respectively, said double rotor (106) being of lenticular shape.

[Claim 8] Double rotor (106) according to the preceding claim characterized in that said two rotary wings (106a, 106b) are associated with one another through a central support (14) having a shaped portion annular (141) from which extends a plate (142), said annular portion (141) being sandwiched between the two rotary wings (106a, 106b), a drive shaft (143) being integrally positioned substantially in the center of the annular portion (141), and being connected to motor means, for rotating said two rotary wings (106a, 106b).

[Claim 9] Double rotor (106) according to the preceding claim, characterized in that said motor means are adapted to impose reverse rotational movements on each of the two upper (106a) and lower (106b) rotary wings.

[Claim 10] An aircraft (200, 201 a, 201 b, 202a, 202b, 203) comprising at least one rotary wing (100, 101, 102, 103, 104, 105) according to any one of claims 1 to 7.

[Claim 1 1] Aircraft (200, 201 a, 201 b, 202a, 202b, 203) according to the preceding claim, characterized in that it comprises at least one additional horizontal speeding means, chosen from a propeller propeller or a traction propeller.

[Claim 12] An aircraft comprising at least one double rotor (106) according to any one of claims 7 to 9.)