METHOD AND SYSTEM FOR GENERATING ELECTRIC ENERGY IN A TYRE

• US 20120211997A1
• Filed: 10/28/2010
• Published: 08/23/2012
• Est. Priority Date: 10/30/2009
• Status: Active Grant

• Current Assignee: Pirelli Tyre SPA (Pirelli & C SPA)
• Original Assignee: Pirelli Tyre SPA (Pirelli & C SPA)
• Inventors: Bonisoli, Elvio, Mancosu, Federico, Brusarosco, Massimo, Moos, Sandro, Repetto, Maurizio, Tornincasa, Stefano, Freschi, Fabio
• Granted Patent: US 8,872,376 B2
• Time in Patent Office: Days
• US Class Current: 290/1.R
• CPC Class Codes: B60C 23/041 Means for supplying power to the signal- transmitting means on the wheel
• CPC Class Codes: F03G 7/08 recovering energy derived from swinging, rolling, pitching or like movements, e.g. from the vibrations of a machine
• CPC Class Codes: H02K 35/02 with moving magnets and stationary coil systems
• CPC Class Codes: H02K 7/1846 structurally associated with wheels or associated parts dynamos arranged in the wheel hub of cycles B62J6/12
• CPC Class Codes: H02K 7/1876 with reciprocating, linearly oscillating or vibrating parts

Abstract

A method and system for generating electric energy in a tyre includes a device including a housing that extends according to a longitudinal axis X, at least one electrical winding, a magnet movable within the housing along the longitudinal axis, and a force providing element positioned at least one of two opposite ends of the housing, which is adapted to exert on the magnet a force along said longitudinal axis. The device is fixed on a crown portion of the tyre; the tyre is rotated on a rolling surface so as to determine variations of forces that act on the device every time the device passes, due to the rolling of the tyre, at a footprint of the tyre; the force exerted by the force providing element and the variations of forces along the longitudinal axis are exploited so as to cause variations of the magnet position with respect to the at least one electrical winding; and the electric energy generated across the at least one electrical winding as a consequence of the variations of the position of the magnet with respect to the electrical winding is collected.

Claims

1-15. -15. (canceled)

16. A method for generating electric energy in a tyre, comprising:

fixing a device on a crown portion of the tyre, said device comprising a housing extending according to a longitudinal axis, at least one electrical winding, a magnet movable within the housing and a force providing element positioned at at least one of two opposite ends of the housing, the magnet being movable with respect to the electrical winding along said longitudinal axis and the force providing element capable of being adapted to exert on the magnet at a force along said longitudinal axis;

rotating the tyre on a rolling surface so as to cause variations of forces acting on the device each time said device passes, due to rolling of the tyre, in correspondence of a footprint of the tyre;

exploiting a force exerted by the force providing element and said variations of forces along said longitudinal axis so as to cause variations of magnet position with respect to the at least one electrical winding; and

collecting electric energy generated across the at least one electrical winding as a consequence of said variations of the magnet position with respect to the at least one electrical winding.

17. The method according to claim 16, wherein the device is fixed onto said crown portion so that the longitudinal axis of the housing is oriented substantially according to a radial direction of the tyre and variations are exploited that a radial force, acting on the device during the rolling of the tyre, undergoes along the longitudinal axis of the housing, every time said device passes in correspondence of a footprint of the tyre.

18. A tyre comprising:

a crown portion;

a monitoring device comprising at least one sensor capable of being adapted to measure at least one operating parameter of the tyre;

an energy generation device associated with said crown portion, capable of being adapted to feed energy to said monitoring device, wherein;

said energy generation device comprises a housing extending according to a longitudinal axis, at least one electrical winding, a magnet movable within the housing and a force providing element at least one of two opposite ends of the housing, the magnet being movable with respect to the electrical winding along said longitudinal axis and the force providing element capable of being adapted to exert on the magnet a force along said longitudinal axis; and

wherein

said at least one electrical winding, said magnet and said force providing element are configured so that the position of the movable magnet with respect to the at least one electrical winding varies during rolling of the tyre, due to action of a force exerted by the force providing element and to variations undergone by forces acting on the energy generation device every time said device passes, due to the rolling of the tyre, in correspondence of a footprint of the tyre.

19. The tyre according to claim 18, wherein the force providing element is capable of being adapted to exert a repulsive force on the magnet, an absolute value of the repulsive force of which increases as the magnet approaches an end where the force providing element is positioned.

20. The tyre according to claim 18, wherein the energy generation device is associated with said crown portion so that the longitudinal axis of the housing is oriented substantially according to a radial direction of the tyre.

21. The tyre according to claim 20, wherein the force providing element is positioned at one of two opposite ends of the housing.

22. The tyre according to claim 21, wherein the energy generation device is associated with said crown portion so that an end of the housing in which the force providing element is positioned faces, according to a radial direction of the tyre, toward the outside of the tyre itself.

23. The tyre according to claim 18, wherein the force providing element is positioned at the two opposite ends of the housing.

24. The tyre according to claim 23, wherein the energy generation device is associated with said crown portion so that the longitudinal axis of the housing is oriented substantially according to a lateral or longitudinal direction of the tyre.

25. The tyre according to claim 18, wherein the energy generation device comprises at least two electrical windings.

26. The tyre according to claim 25, wherein the at least two electrical windings are connected in counter-series.

27. The tyre according to claim 25, wherein the at least two electrical windings are spaced apart from each other by means of a spacer comprising two coxial rings of which one is made from magnetically inactive material and one is made from ferromagnetic material.

28. The tyre according to claim 18, wherein the movable magnet has a residual magnetic induction B_r greater than 1T.

29. The tyre according to claim 25, wherein the force providing element and the movable magnet are capable of being configured so that, at a predetermined rolling speed of the tyre, each time that the energy generation device is outside of a footprint, the movable magnet is, apart from oscillations, in an operating position in which a pattern dλ

/dx of a total magnetic flux λ

coupled by turns of said at least two windings, versus a position of the movable magnet along the longitudinal axis of the housing, has a maximum gradient.

30. The tyre according to claim 29, wherein the force providing element and the movable magnet are configured so that in said operating position of the movable magnet, the energy generation device has a resonance frequency substantially corresponding to a frequency associated with a higher-order contribution peak of forces acting on the energy generation device along said axis of the housing, at said predetermined rolling speed of the tyre.