FR2968726A1 - Wind power device e.g. Savonius rotor-type wind power device, for use on roof of e.g. camping car, has blades inflated to modify spacing between reinforcement elements from deployed position to folded position - Google Patents

Abstract

The device (1) has a rotor with vertical axis carrying blades (9) inserted between lower and upper reinforcement elements (5, 7). The blades are inflated and arranged to modify the spacing between the reinforcement elements from a deployed position of the device to a folded position of the device, where height of the device in the folded position is lower than height of the device in deployed position. A set of units inflates the blades when the device is in the deployed position and deflates the blades when the device is in the folded position.

Description

FOLDING WINDMILL WITH INFLATABLE BLADES

The invention relates to devices for converting wind energy into mechanical or electrical energy such as for example wind turbines. The invention is intended in particular for wind turbine devices with a vertical axis that can for example be mounted on the roof of a vehicle. More specifically, the invention relates to wind devices that can be folded for storage. The invention also relates to a method for deploying and folding a wind turbine device with a vertical axis.

It is known from the prior art different wind devices for converting wind energy into mechanical or electrical energy. The most common are horizontal axis wind turbines (that is, where the axis of rotation of the rotor is horizontal) including multi-blade propellers. There are also wind turbines vertical axis (that is to say where the axis of rotation of the rotor is vertical) comprising for example semicircular curved blades or panels rotating about said central axis.

The use of vertical axis wind turbines has many advantages over horizontal axis wind turbines, such as generating low noise and being set in motion with low wind speeds. Unfortunately they also have the disadvantage of being bulky and are therefore difficult to retract for use as a source of extra energy that can be mounted for example on the roof of a vehicle. Indeed, such wind devices must be deployed when the vehicle is stationary and must be stowed when the vehicle moves or when the user does not use it. For reasons both aesthetic and aerodynamic, the storage and / or retraction of such devices implies that they have, once stored, a footprint as small as possible. Preferably, the operations of deployment or folding and / or retraction of the wind device must be remotely performed by the user without having to act on the device itself. However the congestion presented by vertical axis wind devices makes their simple retraction difficult and there is currently no way to reduce this congestion satisfactorily.

For example, document US7241105 discloses a wind turbine device whose blades of flexible material are fixed to vertically movable reinforcing elements on a central rotary shaft. The folding of the blades by translation of the reinforcing elements on the rotary axis allows to fold the device but does not reduce its size at least according to its height. Any folding of the rotary shaft must be the subject of a separate operation. In addition, the blade deployment or folding system requires human intervention on the wind turbine device and can not be controlled remotely.

The object of the invention is to overcome the drawbacks presented by the prior art by proposing to the person skilled in the art a new wind device which can be folded or retracted so as to have, when folded, a height which is lower than that which it exhibits when it is deployed.

For this purpose the invention relates to a wind turbine device having a vertical axis rotor carrying at least two blades interposed between two lower and upper reinforcing elements and fixed to these reinforcing elements by their upper and lower ends remarkable in this respect. that the blades are inflatable and configured so that their inflation changes the spacing between said armature elements from an extended position of the device to a folded position of the device and vice versa, so that the device presents in the folded position a lower height than it has in the deployed position.

Preferably the reinforcing elements are rigid and spaced vertically from one another.

Preferably, the upper armature element is carried by the blades only.

According to a preferred embodiment of the invention, the device further comprises means for inflating the blades until the device is placed in the deployed position and / or means for deflating the blades until the device is in the folded position.

Advantageously, the inflation of the blades is by compressed air, preferably from their lower end. Optionally, the device further comprises cables intended to be stretched between the reinforcing elements to stiffen said device when it is in the deployed and / or folded position. Optionally, the deflation of the blades is assisted by winding the cables around an axis preferably by means of at least one servo motor. Advantageously, the tension of the cables and the air pressure in the blades are chosen to maintain the angular position of the reinforcing elements relative to one another. Preferably, the blades are made of a plastic material having mechanical characteristics sufficient to be relatively rigid or dimensionally stable when inflated and / or relatively flexible or deformable when deflated. According to a preferred embodiment of the invention, the blades are constituted by at least one envelope comprising a succession of compartments connected to one another and preferably stacked on top of each other. According to one embodiment of the invention, the blades have a semicylindrical profile and / or in that the device is a Savonius type rotor, preferably the device comprises at least three blades. Advantageously, the blades have a diameter greater than half the diameter of the device and are optionally positioned slightly offset from each other, preferably have between them at the central level a spacing of a length of about one sixth of the diameter of the device. device. Optionally, the blades are helically arranged. Preferably, the rotor body does not extend beyond the lower reinforcement element. Optionally, the rotor is mounted on a telescopic mast. The invention also relates to a remarkable vehicle in that it has a wind device as defined above, preferably mounted on its roof.

The use of inflatable blades in wind turbine devices is already known from the prior art and FR2507696 describes a wind turbine device comprising a rotor with a horizontal axis whose blades are inflatable. The blades are likely to deform under the pressure of the wind and can therefore, when the wind is weak, form a large angle with the direction of the wind and tend to fade gradually when the wind speed increases to reduce the stresses to which they are subjected. subjected and especially in case of strong wind to limit the risk of damage to the device. The rotor may also comprise means for varying the overpressure of the blades as a function of its rotational speed.

It will be noted that the overpressure difference of the blades of the device of the prior art offers a greater or lesser possibility for the blades to crash on themselves as a function of the wind speed, which modifies their angular orientation relative to to the wind and therefore the speed of the rotor, this is contrary to the invention where the inflation or deflation of the blades is intended to deploy or fold the wind turbine device and where a difference in overpressure does not change the angular orientation of the blades relative to in the wind.

US201 0/01 431 30 discloses a horizontal axis wind turbine with inflatable blades to lighten the weight of said blades. They preferably have an internal reinforcement to stiffen them.

Document US2006 / 0251505 discloses a horizontal axis wind device having blades extending radially along the axis of rotation. The device is inflatable in order to float in the air. The blades do not have to be inflatable. The blades of the prior device are fixed on the axis of rotation and do not take an active part in the folding or deployment of the device unlike the blades according to the invention.

It will be understood that the invention consists in proposing a wind turbine device having flexible blades comprised between two rigid armature elements and in configuring said blades of means to enable them to modify the spacing between the reinforcing elements so as to modify the overall height of the wind turbine device. The invention consists in providing the wind turbine device with inflatable blades which will carry and lift the upper armature element when they are inflated so as to put the wind device in the deployed position and which will crush for example under the weight said reinforcing member so as to deflate when the pressure is released. According to the invention, the blades are the only bearing elements of the upper reinforcement element on the lower reinforcement element. In this way, the unfolding of the blades by bringing in the air or their folding by chasing the air they contain, will print the upper frame member a movement in the vertical direction that will move away or bring it closer to the lower reinforcement element. It should be noted that it is the spacing difference between the reinforcing elements which defines the different deployed or folded states of the device. The invention will be well understood and other aspects and advantages will become clear from the description which follows given by way of example with reference to the accompanying drawing plates in which: - Figure 1 is a perspective view of a device according to the invention in the deployed position. - Figure 2 is a perspective view of a device according to the invention in the folded position. - Figure 3 is a view of the wind turbine device according to the invention on which the upper armature element has been removed to reveal the arrangement of the blades. - Figure 4 is a perspective view of another embodiment of a device according to the invention.

Reference will firstly be made to FIG. 1 representing an example of a wind device (1) according to the invention. Such a device is able to transform wind power into electrical or mechanical energy by means well known to those skilled in the art and which will not be described further herein. The device according to the invention is for example a device (1) with a vertical axis Savonius type and therefore has blades (9) curved, preferably semi-cylindrical. Those skilled in the art will nevertheless be able to adapt the invention to other types of wind turbine devices with a vertical axis, for example wind turbines of the Darrieus type.

The device (1) according to the invention comprises a rotor with a vertical axis carrying at least two blades (9) placed between two reinforcing elements (5, 7) preferably rigid and spaced vertically from one another. The blades (9) are fixed to the lower reinforcing element (5) by their lower end and fixed to the upper reinforcing element (7) by their upper end. Preferably, the reinforcing elements (5, 7) have a diameter similar to the diameter presented by the arrangement of all the blades (9).

It is specified that the number of blades (9) carried by the rotor of the device (1) can not be limiting of the invention and can be easily modified by those skilled in the art. When deployed, the device (1) is therefore in the form of a vertical axis wind turbine that is to say that the axis of rotation of the main rotor is arranged vertically and is parallel to the axis of the mast (not shown) carrying the wind device (1). The blades (9) are arranged substantially vertically. This type of wind turbine device (1) offers the advantage of being able to be fully effective whatever the direction of the wind. Preferably, the device (1) according to the invention will have at least three blades which will facilitate the rotation of the rotor even in light wind.

According to the invention, the blades (9) are inflatable and configured so that their inflation changes the spacing between the armature elements (5, 7) from an extended position of the device (1) to a folded position of the device (1) and vice versa, so that the device (1) has in the folded position a lower height than it has in the deployed position. In this way the storage and / or retraction of the wind device (1) according to the invention is facilitated. The device (1) according to the invention is therefore able to flatten for storage and preferably it flattens until the lower frame members (5) and upper (7) are spaced vertically a distance corresponding to the thickness that the blades (9) when they are deflated and folded on themselves.

According to a preferred embodiment of the invention, the device (1) further comprises means for inflating said blades (9) until placing the device (1) in the deployed position and / or means for deflating said blades ( 9) until the device (1) is in the folded position. The means are advantageously arranged to act on the blades (9) at their lower end. Preferably, the inflation of the blades (9) is by compressed air. These means may comprise for example a pump for inflation and possibly means for sucking the air present in the blades (9) for deflation. Nevertheless other solutions are possible as we will see later.

Note the absence of central shaft extending between the two frame members (5, 7). In particular, it will be noted that the upper reinforcement element (7) is not connected to any rotating shaft. According to the invention, only the inflatable blades (9) are placed between the reinforcing elements (5, 7) in order to serve as support for the upper reinforcing element (7), and in order to define its spacing relative to the lower armature element (5). Thus the swelling or deflation of the blades (9) has a direct influence on the height at which the upper armature element (7) is located. When the blades (9) are inflated, the upper reinforcing element (7) is raised above the reinforcement element (5) less than a height corresponding to the height of the inflated blades (9). When the blades (9) are deflated, the upper armature member (7) is pushed towards the lower armature member (5) by the action of gravity. The deflated blades (9) remain inserted between the two reinforcing elements (5, 7).

Preferably, the blades (9) of the device (1) according to the invention deflate only when the air pressure is released. This deflation of the blades (9) is advantageously favored by the weight of the upper reinforcing element (7) which will press on the blades (9) in the direction of the lower reinforcement element (5), and thus assist to their deflation. The means favoring the folding of the device (1) are then passive means.

Nevertheless, it is possible in the context of the invention to provide other means to assist the deflation of the blades (9) and for example accelerate or compensate for the use of a reinforcement element (7) greater than low weight. For example, and as illustrated in Figure 4, it is possible to place cables (17) joining the lower frame members (5) and upper (7). When the user decides to fold the wind turbine device (1), the air inlet and / or outlet opening (9) of the blades (9) will be open allowing the air they contain to be released. on the one hand, and on the other hand, the cables (17) will be wound on themselves around an axis by a motor (19) and will pull the upper armature element (7) in the direction of the lower armature element (5). In this way, the pressure exerted by the upper armature member (7) on the blades (9) will evacuate the air they contain more quickly. Once the armature elements positioned close to each other, the cables (17) will maintain the wind device (1) in the folded position. This makes it possible, for example, to avoid any inadvertent lifting of the upper armature element (7) under the pressure of a high speed wind between the two armature elements (5, 7) which could damage the device. (1).

Furthermore, the use of cables (17) rollable or not, will find an advantage in the eyes of the skilled when the device (1) is in the deployed position to stiffen it. When the device (1) is deployed, the cables (17) are advantageously stretched between the two reinforcing elements (5, 7). In FIG. 4 the cables (17) are located at the periphery of the reinforcing elements (5, 7) since the latter have a contour following the profile presented by the blades (9). However, when the reinforcing elements (5, 7) used have a larger surface and for example are in the form of discs cables (17) may be arranged at other locations. The blades (9) of the device (1) according to the invention are advantageously made of a plastic material having sufficient mechanical characteristics to be relatively rigid or indeformable when they are inflated and / or relatively flexible or deformable when deflated. They can be connected by their central end so that they present only one envelope or be in the form of three separate envelopes as illustrated in FIG. 3. Preferably, the thickness of the envelope and the mechanical characteristics of the material used allow the blades (9) to receive air under pressure. On the other hand, in order to stiffen the blades and offer a wall unlikely to be deformed under the action of the wind, the skilled person will find it advantageous to use for the manufacture of the blades (9) envelopes with complex structures. For example, it is possible to use one or more envelopes comprising a succession of compartments interconnected and preferably stacked on one another or next to each other.

Optionally, the envelope or envelopes may consist of a stack of flanges as shown in Figures 1 to 4. The flanges communicate with each other or are independent of each other.

When the device (1) is of Savonius type, the blades (9) are semi-cylindrical and advantageously have a diameter d equal to or greater than half the diameter D presented by the rotor, as illustrated in FIG. the diameter d of the blades (9) is equal to half the diameter D of the rotor, the blades (9) meet at the axis of rotation of the rotor and can form a single envelope. Nevertheless, when the spacing between the two inner and outer lateral edges, and therefore the diameter d, of the blades (9) is greater than half the diameter D of the rotor, the blades (9) are then advantageously arranged so as to be slightly offset. and present in a known manner a spacing e between their inner edges. Preferably, this spacing e has a length between one third and one sixth of the diameter presented by the blades (9) and responds for example to the relationship: In order to linearize the force applied to the blades (9) these will be advantageously arranged helically. This is made possible inter alia by the shape of the envelopes constituting the blades (9) and because of the attachment to the lower and upper ends of the blades (9) on the reinforcing elements (5, 7) and, for example, also by the use of cables (17) allowing, once tensioned to define both a maximum spacing between the reinforcing elements (5, 7) and both their angular positioning. As we have seen, the reinforcing elements (5, 7) may be in the form of disks, as illustrated in FIGS. 1 to 3 or may have other shapes as illustrated in FIG. 4.

It will be understood that ideally the device (1) has no rigid element between the two reinforcing elements (5, 7) so that the flattening of the device (1), or in other words the approximation between the two reinforcing elements (5, 7) are not prevented or limited. This is why the device (1) will not have a central rotary shaft disposed between the two reinforcing elements (5, 7). The rotor body (3), transmitting the rotational movement to the stator, is located below the lower armature member (5) and does not extend beyond the latter. The invention is also directed to vehicles such as motor vehicles or motor homes equipped with a wind device (1) according to the invention.

Said device (1) is preferably mounted on the roof of the vehicle. It is placed in the deployed position when the vehicle is stopped to supply electricity, for example to recharge its battery. When the vehicle moves the device according to the invention is placed in the folded position and is stored in a compartment present on the roof and provided for this purpose. The person skilled in the art may find it advantageous to mount the rotor of the device (1) according to the invention on a telescopic mast and to couple the means of inflating or deflating the blades (9) with increasing or decreasing the height of said mast. to facilitate its retraction and storage for example in a storage box located on the roof of the vehicle. The opening of the storage compartment and the deployment or folding of the device are advantageously controlled from the dashboard of the vehicle.

The invention is not limited to the embodiments described above, given only by way of example, but encompasses all the variants that may be envisaged by those skilled in the art within the framework of the definition that has been given.

Claims (15)

CLAIMS1- A wind generator (1) having a rotor with a vertical axis carrying at least two blades (9) interposed between two lower (5) and upper (7) reinforcing elements and fixed to these reinforcing elements (5, 7) by their lower and upper ends characterized in that the blades (9) are inflatable and configured so that their inflation changes the spacing between said armature members (5, 7) from an extended position of the device (1) to a folded position of the device (1) and vice versa, and in that the device (1) has in the folded position a lower height than it has in the deployed position. 2- wind device (1) according to claim 1 characterized in that the upper frame member (7) is carried by the blades (9) only. 3- wind device (1) according to one of claims 1 or 2 characterized in that it further comprises means for inflating the blades (9) to place the device (1) in the deployed position and / or means for deflating the blades (9) until the device (1) is in the folded position. 4- wind device (1) according to one of claims 1 to 3 characterized in that the inflation of the blades (9) is by compressed air, preferably from their lower end. 5- wind device (1) according to one of claims 1 to 4 characterized in that it further comprises cables (17) intended to be stretched between the reinforcing elements (5, 7) to stiffen said device ( 1) when in the deployed and / or folded position. 30 6. Wind device (1) according to claim 5 characterized in that the deflation of the blades (9) is assisted by the winding of the cables (17) about an axis preferably by means of at least one motor (19). ) enslaved. 7- wind device (1) according to one of claims 5 or 6 characterized in that the tension of the cables (17) and the air pressure in the blades (9) are chosen to maintain the angular position of the elements d armature (5,7) relative to each other. 8- wind device (1) according to one of claims 1 to 7 characterized in that the blades (9) are made of a plastic material having sufficient mechanical characteristics to be relatively rigid or dimensionally stable when inflated and / or relatively soft or deformable when deflated. 9- wind device (1) according to one of claims 1 to 8 characterized in that the blades (9) are constituted by at least one envelope comprising a succession of compartments interconnected and preferably stacked on each other. 10-wind device (1) according to one of claims 1 to 9 characterized in that the blades (9) have a semi-cylindrical profile and / or in that the device (1) is a Savonius-type rotor, preferably the device comprises at least three blades (9). 25 11- a wind device (1) according to claim 10 characterized in that the blades (9) have a diameter greater than half the diameter of the rotor and are optionally positioned slightly offset from each other, preferably present between them at central level a spacing 30 of a length of about one sixth of the diameter of the rotor. 12- wind device (1) according to one of claims 1 to 11 characterized in that the blades (9) are arranged helically. 13- wind device (1) according to one of claims 1 to 12 characterized in that the body (3) of the rotor does not extend beyond the lower armature member (5). 14- wind device (1) according to one of claims 1 to 13 characterized in that the rotor is mounted on a telescopic mast. 15- Vehicle characterized in that it has a wind device (1) according to one of the preceding claims preferably mounted on its roof.