FR3088106A1 - VENTILATION DEVICE COMPRISING AN ELECTRO-ACTIVE ELEMENT - Google Patents

Abstract

The invention relates to a ventilation device (1) intended to be integrated into a vehicle, the ventilation device (1) comprising a plurality of blades (10) fixed to a hub (20), the plurality of blades and the hub being movable in rotation about an axis of rotation (O), the ventilation device (1) comprising at least one electro-active element (31, 32), the ventilation device (1) being arranged to be movable between a first position when the electro-active element (31, 32) is subjected to a first electric voltage and a second position when the electro-active element (31, 32) is subjected to a second electric voltage. Application to motor vehicles.

Description

The field of the present invention is that of ventilation devices for vehicles, and in particular for motor vehicles.

In the state of the art, a ventilation device for a vehicle is known, the ventilation device comprising a hub movable in rotation about an axis of rotation, the ventilation device also comprising a plurality of blades extending radially from the hub outward. An electric motor ensures the rotation of the hub. Thus, when the hub is rotated by the electric motor, the plurality of blades, coupled in rotation with the hub, generates an air flow which is directed towards a heat exchanger, thus allowing to promote the heat exchange. with a coolant circulating inside the heat exchanger.

These known ventilation devices are not entirely satisfactory and have drawbacks. Indeed, the blades are made so that they are able to take a single position. Thus, the blades cannot adapt their shape, and therefore cannot modify the air flow which they generate as a function of various parameters, such as the speed of movement of the vehicle, the cooling needs of the heat exchanger. heat with which the ventilation device is coupled, or the noise generated by the ventilation device. Thus, the blades of a known ventilation device are designed so as to allow a compromise in performance between different theoretical use situations. The blades thus designed are therefore not necessarily suitable for the practical use which is made of the ventilation device, thus forming a first drawback of a known ventilation device. In addition, the control of the air flow generated by the known ventilation device is regulated only due to the activation, deactivation or the speed of rotation of the electric motor coupled to the known ventilation device, and not directly to the level of the ventilation device, thus forming a second drawback.

The object of the present invention is to propose a ventilation device which makes it possible to respond at least in part to the drawbacks mentioned above and also to lead to other advantages. Thus, the present invention aims to allow to adapt, in real time, the air flow generated by the ventilation device according to various parameters. In addition, the present invention aims to allow the adaptation of the air flow generated by the ventilation device directly at the level thereof, and not due to its supply by the electric motor by which it is electrically supplied. .

The invention achieves this, according to a first aspect, thanks to a ventilation device intended to be integrated in a vehicle, the ventilation device comprising a plurality of blades fixed to a hub, the plurality of blades and the hub being movable in rotation. around an axis of rotation, the ventilation device comprising at least one electroactive element, the ventilation device being arranged to be movable between a first position when the electroactive element is subjected to a first electrical voltage and a second position when the electro-active element is subjected to a second electric voltage.

In the following description and in the claims, the terms “internal / internal >> or“ external / external >> relative to the axis of rotation of the ventilation device and in a radial orientation, orthogonal to the axial orientation, "inside" designating a proximal part of the axis of rotation and "outside" designating a distal part of the axis of rotation.

Thus, the use of an electro-active element makes it possible to cause a deformation of the component of the ventilation device, in particular at least pale and / or the hub, comprising said electro-active element, in real time, as a function of the voltage. applied to the latter by a power supply. In fact, said component comprises an active zone in which the electro-active element is located, and an inert zone devoid of electro-active element. Thus, the active zone is the zone which undergoes deformation when the electric voltage applied to the electro-active element is modified, the inert zone for its part ensuring the general structure of the component comprising the electro-active element, thus allowing the deformation to occur at the active area.

The use of an electro-active element allows the component of the ventilation device comprising the electro-active element, known as the active component, to take an infinite number of positions depending on the electric voltage applied to the electro-active element. For example, in the case where the first electrical voltage is a minimum or zero voltage, for example 0 volts, the electro-active element is in a first configuration allowing the active component to be in its first position. When the second electrical voltage is a maximum voltage, for example 4000 volts, the electro-active element is in a second configuration allowing the active component to be in its second position. Thus, when a third electrical voltage, the value of which is between the value of the first voltage and the value of the third voltage, the electro-active element is in a third configuration allowing the active component to be in a third intermediate position between the first position and the second position. This configuration makes it possible to distinguish the ventilation device according to the first aspect of the invention compared to a ventilation device using a shape memory alloy, the shape memory alloys being able to take only two predetermined positions. depending on the conditions, including temperature, to which they are exposed. Thus, the use of electroactive materials makes it possible to remove the constraint of producing a ventilation device having to ensure a compromise in performance between different theoretical conditions of use, the ventilation device according to the invention being able to be adapted in real time to conditions under which it operates.

The ventilation device according to the first aspect of the invention advantageously comprises at least one of the improvements below, the technical characteristics forming these improvements can be taken alone or in combination:

- At least one pale of the plurality of blades of the ventilation device comprises at least one electro-active element. This configuration thus allows the deformation of the at least one blade by the at least one electro-active element when the electric voltage applied to the at least one electro-active element is modified. Advantageously, the at least one electro-active element is located on a portion of the blade, called the first portion, sufficiently distant from the hub in order to form an active area, while a portion, called the second portion, of the blade is located near the hub forms an inert zone;

- an air flow generated during the rotation of the plurality of blades when the blade is in the first position is different from an air flow generated during the rotation of the plurality of blades when the blade is in the second position. This configuration thus makes it possible to adapt the air flow generated by the ventilation device according to different parameters. For example, when the vehicle is traveling at a high speed, the ventilation device can generate a low air flow, the air flow from the movement of the vehicle being sufficient to cool a heat exchanger thermally coupled with the ventilation device. In addition, this configuration makes it possible to reduce aerodynamic drag or even the noise generated by the ventilation device, the vehicle traveling at high speed. Conversely, when the vehicle is traveling at low speed, the air flow generated by the movement of the motor vehicle may not be sufficient to cool the coolant circulating in the heat exchanger with which the ventilation device is thermally coupled. Thus, the electro-active element is then subjected to a second electrical voltage, allowing the blade to take a second position increasing the air flow generated by the ventilation device to favor the cooling of the heat exchanger with which the ventilation device is thermally coupled. Thus, the modification of the air flow generated by the rotation of the plurality of blades makes it possible to modify, for example, the flow rate of the air flow, the aerodynamic drag or even the noise generated by the ventilation device;

- The ventilation device is arranged to generate the air flow in a direction substantially perpendicular or parallel to the axis of rotation. The ventilation device is thus an axial propeller or a squirrel cage propeller. Advantageously, the air flow is generated in a radial direction, in particular in the case where the ventilation device is intended to be integrated into a heating, ventilation, air conditioning system of the vehicle, such as an air conditioning system. vehicle air. Similarly, the air flow is generated in an axial direction, that is to say parallel to the axis of rotation of the ventilation device, in particular in the case where the ventilation device is intended to be integrated in a cooling system, the ventilation device then being coupled with a heat exchanger situated at a front face of the vehicle, the front face of the vehicle being directed towards the front in the main direction of movement of the vehicle;

- Each pale of the plurality of pale includes an electro-active element. This configuration makes it possible to maximize the adaptation of the air flow generated by the plurality of blades of the ventilation device;

- the pale includes a first electro-active element and a second electro-active element. Thus, the first electroactive element and the second electroactive element can be arranged so as to be adjacent to one another. Advantageously, the first electro-active element and the second electro-active element are electrically supplied by two separate electrical supplies. This configuration thus makes it possible to apply a different electrical voltage to each electro-active element, in order to increase the number of deformation profiles that the electro-active element can perform;

- the electro-active element extends between a leading edge and a trailing edge of the blade. The leading edge is the edge of the blade which is directly exposed, during the blade's rotational movement, to the fluid, in particular to the air, in which the blade moves. The trailing edge is located opposite the pale relative to the leading edge. Thus, the fluid in which the blade travels flows over the blade from the leading edge to the trailing edge. This configuration makes it possible to maximize the deformation of the blade between the leading edge and the trailing edge, thus maximizing the modification of the air flow generated by the plurality of blades as a function of the electrical voltage applied to the electro-element. active;

- the electro-active element is configured so as to modify a pitch and / or a camber of the blade. The pitch of the blade designates the angle between a straight line passing through the leading edge and the trailing edge of the blade and an axis perpendicular to the axis of rotation of the ventilation device. Thus, a step of 0 ° means that the leading edge and the trailing edge extend perpendicular to the axis of rotation of the ventilation device. The camber designates a curvature along a transverse axis of the blade perpendicular to a main longitudinal axis of the blade. This configuration allows the modification of the air flow generated by the rotation of the plurality of blades during the modification of the pitch and / or the camber of the blade, the increase in the pitch or the increase in the camber causing the increasing the flow rate of the air flow generated by the rotation of the plurality of blades;

- the electro-active element is placed on a surface of the blade. In other words, the electro-active element is not included in the constituent material forming the pale. Advantageously, the electro-active element is located on a longitudinal face of the blade in the case where the air flow is generated in a longitudinal direction. Similarly, the electro-active element is advantageously located on a circumferential face of the blade in the case where the air flow is generated in a radial direction;

- the electroactive element comprises at least one electroactive composite material. Thus, the electroactive composite material is composed of several distinct layers superimposed between them. More particularly, the electroactive composite material comprises a layer of electroactive material and two electrodes. Preferably, the electro-active material is interposed between the two electrodes;

- Advantageously, the electro-active composite material also comprises a support layer. The support layer maintains the general structure of the electro-active composite. Advantageously, the support layer also makes it possible to define the deformation zone as well as the deformation profile of the electro-active composite material;

- the electro-active element comprises a stack of electro-active composite materials superimposed on each other. This configuration makes it possible to maximize the deformation of the electro-active element and / or to increase the number of deformation profiles that the electro-active element can undergo;

- the electroactive composite materials are electrically connected to each other in series and / or in parallel;

- the thickness of the electro-active composite material is between 0.2 millimeter and 5 millimeters. The thickness of the electroactive composite material is measured in the stacking direction of the layers of the electroactive composite material;

- the first electrical voltage and the second electrical voltage are between 50 volts and 4000 volts. Advantageously, the first electrical voltage and the second electrical voltage are between 1000 volts and 1500 volts. Advantageously, when no electrical voltage is applied to the electro-active element, for example following a breakdown of the electrical supply connected to the electro-active element, the latter is then in a rest configuration, the blade then being in a basic position still allowing the plurality of blades to generate an air flow. This configuration makes it possible to ensure the generation of an air flow during the rotation of the ventilation device and this even in the event of an unintentional interruption of the electrical supply connected to the electro-active element;

- The ventilation device comprises a peripheral ring on which the blades are fixed. The peripheral ring maintains an end, called the second end, located opposite the blade relative to the end, called the first end, fixed on the hub. Thus, the peripheral ring makes it possible to form an inert zone near the second end, that is to say near the peripheral ring. According to this configuration, each blade then includes a first inert zone close to its first end and a second inert zone close to its second end, thus promoting the deformation of the blade in a central zone located between the first end and the second end;

- The material of the plurality of blades is identical to a material of the hub. This configuration makes it easier to manufacture a ventilation device in accordance with the first aspect of the invention. Advantageously, said constituent material is a plastic material, for example a polypropylene polymer or a polyamide polymer;

- The hub of the ventilation device comprises at least one electroactive element. This configuration makes it possible in particular to modify the aerodynamic performance of the ventilation device by deformation of the hub of the ventilation device;

the vehicle is a motor vehicle. More particularly, the motor vehicle is a car or a truck.

According to a second aspect, the invention also relates to a ventilation system comprising a ventilation device in accordance with the first aspect of the invention and a control box controlling a power supply associated with the at least one electro-active element.

The control unit receives information, for example on the speed of the vehicle or on the temperature of the coolant, from various sensors. Thus, the control unit can adapt the configuration of the ventilation device by deforming the blade due to the modification of the electrical voltage applied by the power supply to at least one electroactive element included on said blade.

This configuration according to the second aspect allows the control, by the control unit, of the electric voltage applied to the at least one electro-active element in order to adapt the configuration of the ventilation device to the conditions in which the ventilation device operates. .

The ventilation system according to the second aspect of the invention advantageously comprises at least one of the improvements below, the technical characteristics forming these improvements can be taken alone or in combination:

- The control unit controls a first electrical supply and a second electrical supply respectively associated with a first electro-active element and a second electro-active element. This configuration makes it possible to apply different voltages to the first electro-active element and to the second electro-active element, in order to maximize the number of conformations that the ventilation device can take;

- The first electro-active element and the second electro-active element are located on different blades;

- Alternatively and advantageously, the first electroactive element and the second electroactive element are located on the same blade. This configuration makes it possible to maximize the deformation of said blade by the first electro-active element and the second electro-active element. In addition, this configuration makes it possible to maximize the number of conformations that the blade can take, the first electrical supply applying a first electrical voltage to the first electro-active element, the second electrical supply applying a second electrical voltage to the second electro-active element, the first electrical voltage and the second electrical voltage may be different.

Other characteristics, details and advantages of the invention will emerge more clearly on reading the description which follows on the one hand, and several examples of embodiment given by way of non-limiting indication with reference to the schematic drawings annexed on the other share, on which:

- Figure 1 illustrates the aerodynamic performance of a known ventilation device under different conditions;

- Figure 2 illustrates a perspective view of a first embodiment of a ventilation device according to the first aspect of the invention;

- Figure 3 illustrates a perspective view of a second embodiment of a ventilation device according to the first aspect of the invention;

- Figure 4 illustrates schematically in sectional view an embodiment of an electro-active element intended to be integrated in a ventilation device according to the first aspect of the invention;

- Figure 5 illustrates a partial perspective view of an exemplary embodiment of a ventilation device, the view being focused on a blade, said blade being in a first position;

- Figure 6 illustrates a partial perspective view of the ventilation device illustrated in Figure 4, the view being focused on a blade, said blade being in a second position;

- Figure 7 illustrates a perspective view of an exemplary embodiment of a ventilation system according to the second aspect of the invention.

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The characteristics, variants and different embodiments of the invention can be combined with one another, in various combinations, insofar as they are not incompatible or mutually exclusive of each other. It is possible in particular to imagine variants of the invention comprising only a selection of characteristics described below in isolation from the other characteristics described, if this selection of characteristics is sufficient to confer a technical advantage or to differentiate the invention from in the prior art.

In particular, all the variants and all the embodiments described can be combined with one another if nothing is technically opposed to this combination.

Figure 1 illustrates the aerodynamic performance of a known ventilation device under different conditions.

More particularly, FIG. 1 illustrates the aerodynamic performance of the known ventilation device as a function of the flow D to which it is exposed, the flow D representing the speed of the air flow, known as the inlet air flow, to which the ventilation device. The rotation of the known ventilation device allows the generation, by the ventilation device, of an outlet air flow. The difference between the speed of the inlet air flow and the outlet air flow makes it possible to generate a pressure difference dP, allowing the circulation of the air flow from an inlet of the known ventilation device in the direction of an outlet from the known ventilation device.

Thus, FIG. 1 illustrates the aerodynamic performance of a known ventilation device when it is exposed to a first nominal flow D1 in which the known ventilation device has a maximum efficiency E1, the efficiency E of the ventilation device being the rate of energy used by the ventilation device which is converted to form the outlet air flow. However, when using the known ventilation device on a motor vehicle, the first nominal flow D1 is only encountered during a fraction of the use of the known ventilation device. Indeed, the known ventilation device is intended to evolve in a multitude of different conditions, n

and in particular different flow rates, the known ventilation device must also ensure sufficient ventilation of a device of the motor vehicle to which it is coupled, in all of the conditions under which the known ventilation device is intended to operate. Thus, the known ventilation device, not being able to adapt to the conditions in which it operates, must present a compromise in performance between the ventilation that it generates and its efficiency.

Thus, FIG. 1 illustrates the evolution Pa of the pressure difference dP, as well as the evolution Pe of the efficiency E of the known ventilation device, as a function of the flow rate to which said known ventilation device is exposed.

More particularly, it can be seen that when the known ventilation device is subjected to a second flow D2 lower than the first flow D1, the known ventilation device has a second efficiency E2 reduced compared with the first efficiency E1 of the known ventilation device when that -this is exposed to the first flow D1, in particular because the known ventilation device is designed to operate optimally at a higher flow than the second flow D2. Similarly, it can be seen that when the known ventilation device and subjected to a third flow D3 greater than the first flow D1, the known ventilation device has a third efficiency E3 reduced compared to the first efficiency E1 of the ventilation device known when this is exposed to the first flow D1, in particular because the flow at which the known ventilation device is increased while the speed of the outlet air flow is constant, the known ventilation device being in particular not capable of 'adapt its conformation so as to increase the speed of the outlet air flow it generates, thus causing a decrease in the pressure difference dP, resulting in a decrease in the efficiency E of the known ventilation device.

FIG. 1 illustrates the modification of the efficiency of the known ventilation device as a function of the flow rate to which it is exposed. The efficiency E of the known ventilation device also changes in a similar manner as a function of the speed of rotation of the known ventilation device.

It can thus be seen that a known ventilation device, which cannot adapt its conformation according to the conditions in which it operates, does not allow optimum efficiency to be obtained when the conditions, in particular the aerodynamic conditions, in which it operates are modified. The present invention thus aims to allow the adaptation of the ventilation device so that it adapts to the conditions in which it operates in order to present optimum efficiency, even when the conditions in which it operates, in particular the flow rate to which the ventilation device is exposed, are modified.

Figure 2 illustrates a perspective view of a first embodiment of a ventilation device 1 according to the first aspect of the invention. The ventilation device comprises a plurality of blades 10 fixed on a hub 20. The ventilation device 1 is movable in rotation about an axis of rotation O.

The hub 20 comprises a flange 22 of radial extension delimited radially on the outside by a bearing 24 of axial elongation from which each blade 10 of the plurality of blades extends radially outward. The ventilation device 1 also comprises a peripheral ring 40 of circumferential extension connecting all of the blades of the plurality of blades. Thus, an outer radial end 18 of each of the blades 10 is in abutment against the peripheral ring 40, the outer radial end of a blade 10 being located opposite the blade 10 relative to an inner radial end 16 resting against the bearing surface 24 of the hub 20. Thus, the inner radial end is a first end, the outer radial end is a second end.

The ventilation device 1 is associated with an electric motor, not shown, allowing it to rotate around the axis of rotation O. The rotation of the ventilation device 1 causes the generation, by the plurality of blades, of a flow of air FA, the air being sucked in at the front AV of the ventilation device, and ejected at the back AR of the ventilation device, the front AV and the rear AR being defined according to the direction air flow FA, the direction of air flow FA itself being a function of the direction of rotation R of the ventilation device 1. In this embodiment, the air flow FA is generated in an axial direction, that is to say parallel to the axis of rotation O.

The direction of rotation R makes it possible to define at each blade 10 a leading edge 12 and a trailing edge 14 situated opposite the blade 10 relative to the leading edge 12. The leading edge 12 is the edge of the blade which is exposed directly, due to the rotation of the ventilation device 1, to the fluid in which the ventilation device moves.

Each blade 10 comprises a first electro-active element 31 and a second electro-active element 32 situated at the level of a central zone 17 interposed radially between the inner radial end 16 and the outer radial end 18 of the blade. It should be noted that in FIG. 2, the first electro-active element 31 and the second electro-active element 32 are only represented on a single pale in order to facilitate understanding. Thus, the central zone 17 is an active zone, while an inert zone is formed near each of the inner radial ends 16 as well as near each of the outer radial ends 18. It should be noted that in another example embodiment, a pale could include a single electro-active element without departing from the scope of the invention.

The first electro-active element 31 and the second electro-active element 32 each extend between the leading edge 12 and the trailing edge 14 of the blade 10.

The ventilation device 1 comprises a third electro-active element 33 located on the hub 20, and more particularly at a junction 28 between the flange 22 of radial extension and the bearing surface 24 of axial extension of the hub 20, the third electro-active element 33 extending circumferentially over the entire length of said junction 28. In another embodiment, the hub 20 could comprise an electro-active element on the flange 22 and / or on the bearing surface 24 and / or on another component of the hub, without departing from the scope of the present invention.

The first electro-active element 31 and the second electro-active element 32 make it possible to deform the blade 10 when the respective electric voltage which is applied to the first electro-active element and to the second electro-active element is modified. Likewise, the third electro-active element 33 makes it possible to deform the hub 20 when the electric voltage which is applied to said third electro-active element 33 is changed. Thus, the first electro-active element 31, the second electro-active element 32 and the third electro-active element 33 make it possible in particular to modify the aerodynamic performance of the ventilation device 1.

Figure 3 illustrates a perspective view of a second embodiment of a ventilation device according to the first aspect of the invention.

In this exemplary embodiment, the blades 10 extend from the hub 20 parallel to the axis of rotation O, that is to say perpendicular to the flange 22 of radial extension of the hub. Thus, each blade comprises a proximal end 25 located near the hub along the axis of rotation, and a distal end 26 situated opposite said blade relative to the proximal end 25. Each blade therefore comprises a median zone 27 located between the proximal end and the distal end. This embodiment also includes a peripheral ring 40 connecting the distal end of each of the blades of the ventilation device. Thus, the proximal end forms a first end of the blade, the distal end forms a second end of the blade.

In this exemplary embodiment, the air flow FA, generated during the rotation of the ventilation device, is generated in a radial direction. According to the direction of rotation illustrated in Figure 3, the air flow FA is generated radially outwards.

Each blade 10 comprises a first electro-active element 31 and a second electro-active element 32 situated at the level of the median zone 27. It is thus understood that the median zone forms an active zone, while an inert zone is formed nearby. from the proximal end 25 as well as near the distal end 26 of each blade 10. More particularly, the first electro-active element 31 and the second electro-active element 32 extend between the leading edge 12 and the trailing edge 14 of the pale. As in FIG. 2, it should be noted that each blade 10 of the ventilation device comprises a first electro-active element 31 and a second electro-active element 32, the first electro-active element 31 and the second electro-active element 32 being represented only on a single pale in order to facilitate understanding

Figure 4 schematically illustrates in sectional view an embodiment of an electro-active element 31,32 intended to be integrated in a ventilation device according to the first aspect of the invention. Thus, the electroactive element comprises at least one electroactive composite material 35.

The electroactive composite material 35 comprises, in this embodiment, a first layer 38 of electroactive material, such as a polymer, interposed between a second layer 34 and a third layer 36, the second layer and the third layer forming electrodes making it possible to apply an electrical voltage to the electroactive material included in the first layer 38, the first layer being the layer responsible for the deformation of the electroactive composite 35 when an electrical voltage is applied to it. For example, the electrodes included in the second layer 34 and / or the third layer 36 can be carbon, graphite or graphene electrodes. The polymers used for the electroactive material are, for example, fluorinated polymers, such as polyvinylidene fluoride, or also copolymers and or terpolymers containing polyvinylidene fluoride.

The electro-active composite material 35 represented comprises a support layer 39 situated opposite the electro-active composite material 35 with respect to the second layer 34. In other words, the third layer 36 is interposed between the first layer 38 and the layer support 39. The support layer 39 is formed for example of a polymer having a flexibility allowing the deformation of the electro-active composite material 35.

The electroactive composite material 35 also comprises at least one electrically insulating layer, not shown in FIG. 4. Thus, the at least one insulating layer can be located between the first layer 38 and the second layer 34, and / or between the first layer 38 and the third layer 36, and / or between the third layer 36 and the support layer 39 and / or between the second layer 34 and the exterior.

According to a variant embodiment not shown, the electroactive element 31, 32 can be formed by a stack of several electroactive composite materials 35 superimposed and electrically connected to each other in series and / or in parallel as a function of the desired deformation and the configuration of each electro-active composite material 35.

Figures 5 and 6 illustrate a partial perspective view of an embodiment of a ventilation device according to the first aspect of the invention, the view being focused on a blade, said blade being shown in a first position at the Figure 5 and in a second position in Figure 6.

The first electro-active element 31 and the second electro-active element 32 are configured to modify the pitch and the camber of the blade 10 at the level of the central zone 17 when the electric voltage which is applied to them is modified.

The pitch of the blade corresponds to the angle of inclination of the blade, that is to say the angle formed between a straight line D passing through the leading edge 12 and the trailing edge 14, and an axis Z extending circumferentially relative to the axis of rotation O. Thus, in the embodiment illustrated in Figures 5 and 6, the pitch of the blade at its inner radial end 16 is about 20 °.

The camber of the blade corresponds to a curvature of the blade along a transverse axis Y of the blade, the transverse axis Y of the blade being perpendicular to a main axis of elongation X of said blade.

Thus, a first electrical voltage, in particular zero, is applied to the first electro-active element 31 and to the second electro-active element 32 of the ventilation device 1 illustrated in FIG. 5, a second electrical voltage, in particular greater than 50 volts, being applied to the first electro-active element 31 and to the second electro-active element 32 of the ventilation device 1 illustrated in FIG. 6. Thus, the first electric voltage allows the implementation of a first configuration 41 of the first electro-active element 31, as well as the implementation of a first configuration 51 of the second electro-active element 32. The second electrical voltage allows the implementation of a second configuration 42 of the first electro-active element 31, as well as the implementation work of a second configuration 52 of the second electro-active element. It should be noted that in FIG. 6, the dotted lines illustrate the first configuration 41 of the first electro-active element 31 and the first configuration 51 of the second electro-active element 32 as shown in FIG. 5, in order to facilitate the understanding of the difference between the first configuration 41 and the second configuration 42 of the first electro-active element 31 as well as the difference between the first configuration 51 and the second configuration 52 of the second electro-active element

32.

The transition from the first configuration 41 to the second configuration 42 of the first electro-active element 31 as well as the transition from the first configuration 51 to the second configuration 52 of the second electro-active element 32 allows a deformation of the central zone 17 of the blade , which then passes from a first position, illustrated in FIG. 5, to a second position illustrated in FIG. 6. The deformation of the central zone 17 makes it possible to modify the pitch and the camber of the blade 10 to the level of the zone central unit 17 and thus modify the air flow generated by the rotation of the plurality of blades of the ventilation device 1 as a function of the electric voltage applied to the first electro-active element 31 and / or to the second electro-active element 32. More particularly, the camber of the blade, at the level of the central zone 17, in the second position illustrated in FIG. 6, is higher, in particular near the trailing edge 14, than when the blade is in the first position illustrated in figure 5.

Thus, due to the increase in pitch and the camber of the blade at the central zone 17, the configuration illustrated in FIG. 6 allows the flow rate of the air flow generated by the ventilation device to be increased. compared to the configuration illustrated in Figure 5.

It is thus understood that, as a function of the electric voltage applied to the first electro-active element and / or to the second electro-active element, the air flow generated by the ventilation device can be modulated as a function of different parameters, such as the conditions under which the ventilation system operates.

FIG. 7 illustrates a perspective view of an exemplary embodiment of a ventilation system 100 in accordance with the second aspect of the invention.

The ventilation system 100 comprises a ventilation device 1 in accordance with the first aspect of the invention, as well as a control box 110, responsible for controlling the electrical voltage applied to the electro-active element of the ventilation device 1.

More particularly, the ventilation device of the ventilation system 100 is the ventilation device illustrated in FIG. 2.

The control box 110 receives information from various sensors not shown, such as a speed sensor or even a temperature sensor from a device thermally coupled with the ventilation device. The control unit 110 controls a first electrical supply 113 and a second electrical supply 114, respectively connected to the first electro-active element by a first electrical connection 111, and to the second electro-active element by a second electrical connection 112. The first connection electrical 111 and the second electrical connection 112 allow the application of an electrical voltage, generated by the first electrical supply and the second electrical supply, to the first electro-active element 31 and to the second electro-active element 32, respectively. Thus, the control unit allows the application of a first electrical voltage to the first electro-active element 31 which then takes a first configuration, the control unit also allowing the application of a second electrical voltage, independent of the first electric voltage applied to the first electro-active element, to the second electro-active element 32 which then takes a second configuration. Thus, the ventilation system 100 illustrated makes it possible to maximize the deformation of each blade comprising a first electro-active element and a second electro-active element, thus promoting the adaptation of the air flow generated by the ventilation device according to the conditions under which it evolves, in particular as a function of the information received by the control unit 110.

Of course, the invention is not limited to the examples which have just been described and numerous modifications can be made to these examples without departing from the scope of the invention. In particular, the different characteristics, forms, variants and embodiments of the invention can be associated with each other in various combinations as long as they are not incompatible or mutually exclusive. In particular, all the variants and embodiments described above can be combined with one another.

The invention, as just described, achieves the goals it set for itself and makes it possible to propose a ventilation device capable of adapting to the conditions in which it evolves, due to the modulation. of the electrical voltage applied to an electro-active element of the ventilation device, allowing the ventilation device to assume several positions, thus allowing, for example, to favor the cooling of a device coupled with said ventilation device when this is necessary, or else to reduce the noise generated by the ventilation device when possible, or else to modify the aerodynamic performance of the ventilation device as a function of the conditions in which it operates, and in particular as a function of the flow rate to which it is exposed . Variants not described here could be implemented without departing from the context of the invention, since, in accordance with the invention, the ventilation device comprises an electro-active element.

Claims (11)

1. Ventilation device (1) intended to be integrated into a vehicle, the ventilation device comprising a plurality of blades (10) fixed on a hub (20), the plurality of blades (10) and the hub (20) being movable in rotation about an axis of rotation (O), characterized in that the ventilation device (1) comprises at least one electro-active element (31, 32), the ventilation device (1) being arranged to be movable between a first position when the electro-active element (31, 32) is subjected to a first electric voltage and a second position when the electro-active element (31, 32) is subjected to a second electric voltage. 2. Ventilation device (1) according to the preceding claim, in which at least one blade (10) of the plurality of blades (10) of the ventilation device (1) comprises at least one electro-active element (31,32) . 3. Ventilation device (1) according to any one of the preceding claims, in which an air flow (FA) generated during the rotation of the plurality of blades (10) when the blade (10) is in the first position is different from an air flow generated during the rotation of the plurality of blades (10) when the blade (10) is in the second position. 4. Ventilation device (1) according to any one of the preceding claims, arranged to generate the air flow (FA) in a direction substantially perpendicular to the axis of rotation (O). 5. Ventilation device (1) according to any one of claims 1 to 3, arranged to generate the air flow (FA) in a direction substantially parallel to the axis of rotation (O). 6. Ventilation device (1) according to any one of the preceding claims, in which the electro-active element (31, 32) extends between a leading edge (12) and a trailing edge (14) pale (10). 7. Ventilation device (1) according to any one of the preceding claims, in which the electro-active element (31, 32) is configured so as to modify a pitch and / or a camber of the blade (10). 8. Ventilation device (1) according to any one of the preceding claims 5, in which the electro-active element (31,32) is disposed on a surface of the blade (10). 9. Ventilation device (1) according to any one of the preceding claims, in which the blade (10) comprises a first electro-active element (31) and a second electro-active element (32). 10. Ventilation device (1) according to any one of the preceding claims, in which the hub (20) of the ventilation device (1) comprises at least one electro-active element (31,32). 11. Ventilation system (100) comprising a ventilation device (1) according to any one of the preceding claims and a control box (110) controlling an electrical supply associated with the at least one electroactive element (31 , 32).