DEVICE FOR GENERATING ELECTRIC CURRENT IN A FLUID FLOW CIRCUIT

Abstract

-- A device for generating electric current in a fluid flow circuit, including a duct segment interposed in the fluid flow circuit, a rotor mounted in the duct segment and movable by the passage of a fluid through the device, and a stator or stator circuit cooperating with the rotor and producing electric current. The rotor is made up of a transverse flow turbine, the axis of rotation of which extends across the duct segment, the turbine having at the longitudinal ends of its axis of rotation means for holding against the opposite walls of the duct segment, the stator or stator circuit being positioned outside the duct segment at an end of the turbine which is able to be driven in rotation while the turbine moves, and includes structure for generating a magnetic flux for cooperating with the stator or stator circuit in order to produce the electric current.

Claims

1. A device for generating electric current in a fluid flow circuit, comprising: a conduit segment, intended to be interposed in the fluid flow circuits; a rotor mounted in the conduit segment and suitable to be moved by the passage of a fluid in said device; and a stator or a stator circuit arranged to cooperate with the rotor and produce the electric currents; the rotor is constituted by a cross-flow turbine, the axis of rotation of which extends across the conduit segment, the turbine comprising at the longitudinal ends of its axis of rotation, means (24) for holding against the opposite walls of the conduit segment; the stator or stator circuit being positioned outside the conduit segment at the level of one end of the turbine which can be driven in rotation during the movement of the turbine, and comprises means for generating a magnetic flux in order to cooperate with said stator or stator circuit to produce the electric current.

2. The device according to claim 1, characterized in that the turbine has at the longitudinal ends of its axis of rotation bearing assemblies with ball bearings, said bearing assemblies being mounted in housings arranged on the conduit segment to hold the turbine transversally in the conduit segment and allow the rotation of the turbine.

3. The device according to claim 2, characterized in that the ball bearings are ceramic.

4. The device according to claim 2, characterized in that the turbine is constituted by two hubs between which extend blades, preferably two, capable of being driven in rotation under the effect of the flow of a fluid in the conduit, each hub having a bearing assembly and at least one of the hubs bearing the means of generating a magnetic flux.

5. The device according to claim 4, characterized in that the means for generating a magnetic flux are permanent magnets.

6. The device according to claim 4, characterized in that each blade extends between the hubs, the central part of a blade sweeping a cylinder of revolution about the axis of rotation.

7. The device according to claim 6, characterized in that the blades of the turbine are produced by pultrusion of composite materials then bent.

8. The device according to claim 6, characterized in that the blades of the turbine are produced from food grade stainless steel extruded through a die then bent.

9. The device according to claim 4, characterized in that at least one said hub is constituted by a flat disk.

10. The device according to claim 4, characterized in that aat least one said hub is constituted by a domed-shaped disk.

11. The device according to claim 4, characterized in that the axis of rotation (A) of the turbine is constituted by a shaft extending between the hubs.

12. The device according to claim 4, characterized in that the axis of rotation (A) of the turbine is constituted only by the two bearing assemblies.

13. The device according to claim 1, characterized in that the stator or stator circuit also constitutes the electricity generator.

14. The device according to claim 1, characterized in that the stator or stator circuit comprises one or more magnetic coupler elements that can be driven in rotation, allowing the direct mechanical drive of one or more electricity generators.

15. The device according to claim 1, characterized in that the stator or stator circuit comprises one or more magnetic multiplier/coupler elements allowing the mechanical drive of one or more electricity generators.

16. The device according to claim 1, characterized in that the ends of the conduit segment are provided with means of fastening in the fluid flow circuit.

17. A fluid flow circuit comprising at least one electrical appliance such as a sensor, characterized in that said circuit comprises a device for generating electrical energy according to claim 1, incorporated in the circuit, and intended to supply the electrical appliance with electrical energy.

18. A cross-flow turbine, comprising two blades extending between two hubs aligned on the axis of rotation (A), the central part of said blades being capable of being driven in rotation, sweeping a surface inscribed within a cylinder of revolution about the axis of rotation (A), intended to be used in a device according to claim 1, characterized in that each hub is presented in the form of a flat or domed disk driven in rotation by the blades, at least one of its hubs comprising means for generating a magnetic flux, holding means aligned on the axis of rotation (A) being borne by each hub.

Description

[0055] A description of the invention will now be given in greater detail with reference to the figures, which represent:

[0056] [FIG. 1] an exploded perspective top view of a first embodiment of a device according to the invention;

[0057] [FIG. 2] a perspective front view of the embodiment in FIG. 1;

[0058] [FIG. 3] a perspective side view of the device in FIG. 1;

[0059] [FIG. 4] a longitudinal cross section view along the cut plane A-A in FIG. 2;

[0060] [FIG. 5] an exploded perspective top view of a variant of the device in FIG. 1;

[0061] [FIG. 6] a perspective front view of the embodiment in FIG. 5;

[0062] [FIG. 7] a perspective side view of the device in FIG. 5;

[0063] [FIG. 8] an exploded perspective top view of a second embodiment of the invention;

[0064] [FIG. 9] an exploded perspective top view of a variant of the device in FIG. 8;

[0065] [FIG. 10] an exploded perspective top view of a third embodiment of the invention; and

[0066] [FIG. 11] an exploded perspective top view of a variant of the device in FIG. 10;

[0067] [FIG. 12] an exploded perspective view of another embodiment of a device according to the invention;

[0068] [FIG. 13] a perspective side view of the device in FIG. 12; and

[0069] [FIG. 14] a cross section view along the cut line A-A in FIG. 13.

[0070] The device for generating electric current according to the invention comprises a conduit segment 1 in which is mounted a rotor 2. A stator 3 is installed at the outer periphery of the conduit 1 to cooperate with the rotor 2.

[0071] The rotor 2 is constituted by a cross-flow turbine installed in the conduit segment 1 such that the axis of rotation A of the turbine 2 extends transversally in the conduit segment 1. This circular-section turbine 2 has two blades 22 and has a transversal axis.

[0072] This turbine 2 is constituted by two hubs 21 between which extend the blades 22, preferably two. These blades 22 are mounted symmetrically with respect to the axis of rotation A of the turbine 2 and mobile in rotation about the axis A under the effect of a fluid flow F flowing in the conduit 1.

[0073] In movement, the blades 22 sweep a surface inscribed within a cylinder of revolution about the axis A.

[0074] Each blade 22 extends between the hubs 21 along a curve substantially following the circular cross section of the conduit, but any type of blades originating from transverse-flow turbines can be used, provided that the central part of the blade sweeps a cylinder of revolution. The shape of the blades can also be a U-shape, or any suitable shape. Preferably, the blade ends are fixed to the hubs. Preferably, the blades 22 of the turbine are produced by pultrusion of composite materials then bent to obtain a circular cross section. In particular, they can be produced from food grade stainless steel, extruded in a die then bent to obtain a circular cross section.

[0075] Each hub 21, 21′ is presented in the form of a domed disk in the shape of a cup or dome as shown in FIG. 1, or flat as shown in FIG. 12, driven in rotation by the blades 22. One of the hubs 21 contains permanent magnets 23 placed so as to be positioned facing the wall of the conduit segment 1. The variable magnetic flux is transmitted through the wall of the conduit 1 and induces, within the coils of the stator circuit 3 positioned on the outside of the conduit 1 opposite this end of the turbine 2, an electric current that is then exploited.

[0076] The second hub 21′ has no permanent magnets in this example.

[0077] A variant of this first embodiment is shown in FIG. 5 in which, for applications for which it is required to transmit a higher torque, a second hub 21 is used, bearing magnets 23, and placed opposite the first on the conduit 1. By virtue of this device, it is possible to double the torque that can be transmitted.

[0078] The two-bladed transversal-axis turbine 2 is thus intended to form an integral part of a conduit of any cross section (circular as shown in the figures but also, square, rectangular or any polygon) in which a fluid, in particular liquid, flows.

[0079] This turbine 2 is held in the conduit by two bearing assemblies 24 arranged at the centre of the hubs in the form of a domed disk 21. These two bearing assemblies 24 hold the turbine against the opposite walls of the conduit segment 1, these bearing assemblies preferably being lodged in housings arranged for this purpose in the wall of the conduit segment 1 so that the axis of rotation A of the turbine is orthogonal to the axis of the current flow of the fluid F. Thus, holding the turbine 2 in the conduit segment 1 in this way needs neither watertightness nor lubrication. The power of the turbine 2 is transmitted to the outside of the conduit by means of a magnetic device using one or more hubs equipped with permanent magnets over the whole of its circumference. As can be seen in FIGS. 12 and 14, the conduit segment 1 can comprise housings 13 in which the bearing assemblies 24 are mounted. The hubs 21 are mounted capable of being driven in rotation about the bearing assemblies 24.

[0080] The surface of transfer of this power in the direction of the outside of the conduit segment 1 only corresponds to a small angular sector of said conduit segment and does not in any way need the use of the entire peripheral surface of said conduit segment for the entire transmission of the turbine torque in magnetic form.

[0081] FIGS. 8 and 9 show a device according to the invention in which the turbine 2 of the same type as those in the preceding figures in which a magnet-carrier element 4 for transmitting the mechanical torque of the turbine is installed on the outside of the conduit. This magnet-carrier element 4 can thus be firmly fixed to a standard mass-produced electricity generator 5 (of the synchronous type with a radial-flux permanent magnet for example).

[0082] Thus, under the effect of the fluid flow F, the blades 22 are driven in rotation, driving in rotation the hub 21 bearing the magnets 23. The magnet-carrier 41 placed opposite is also driven in rotation. This magnet-carrier element 41 is connected by a shaft 6 to a generator 5. The magnet-carrier element 41/shaft 6 assembly is enclosed in a casing 7.

[0083] FIG. 9 shows a variant comprising a second generator, for applications needing high torques.

[0084] Such an embodiment thus provides both a very low resale price as well as very good yields. It is also notable that this embodiment can also be combined with a pipe having a square or rectangular cross section so as to limit the air gap between the two magnetic supports, inner (hub) and outer (magnet-carrier element), and thus allow effective transmission.

[0085] FIGS. 10 and 11 show an embodiment of the device of the invention in which an outer magnetized coupler element 42 is used in combination with a magnetic multiplier 8 as a stator circuit so as to increase the rotation speed of the output shaft in order to be able to use a permanent-magnet synchronous generator 9 with a high rotation speed.

[0086] Thus excellent (mechanical-to-electrical) conversion yields are obtained while still using low-cost, high-performance generators. In addition, the magnetic multiplier causes almost no loss, and can become very economic to produce provided that a sufficient number are constructed. It is also notable that this embodiment can also be combined with a pipe having a square or rectangular cross section so as to limit the air gap between the two magnetic turrets, inner and outer, and thus allow effective transmission of the torque to the outside.

[0087] In the examples shown above, the axis of rotation A of the turbine 2 is constituted only by the bearing assemblies 24 around which the hubs 21 bearing the blades 22 are driven in rotation.

[0088] FIGS. 12 to 14 show an embodiment example of the device according to the invention, in which a shaft 25 extends centrally between the two hubs 21 thus constituting the axis of rotation A extending transversally in the conduit segment 1.

[0089] As can be seen in FIGS. 12 and 14, the conduit segment 1 is shaped to have within these opposite walls, two orifices 11 in which are lodged the ends of the turbine 2, held in place by two end plates 12.

[0090] The hubs 21 are here constituted by two flat disks having, at least for one, magnets 23 at its periphery. Each hub 21 has at its centre a bearing assembly 24 as well as a shaft 25 extending between the two hubs 21 and constituting the axis of rotation A of the turbine. An end plate 12 is attached on each hub 21 and comprises a housing 13 in which a bearing assembly 24 is positioned and one end of the rotation shaft 25 of the turbine 2. The bearing assembly 24 is mounted fixed in the housing 13 of the conduit segment 1 and the shaft 25 is rotational and firmly fixed to the hubs 21. Thus a device is obtained that is simple to implement, the simple structure of which also confers great robustness thereto. The blades 22 extend diametrically opposite to one another on one side and on the other side of the axis of rotation A between the hubs 21, with their ends connected to the hubs 21.