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EP-4474174-B1 - TYRE COMPRISING A MONITORING DEVICE

EP4474174B1EP 4474174 B1EP4474174 B1EP 4474174B1EP-4474174-B1

Inventors

  • PUPPI, CRISTIANO
  • BOSCAINO, IVAN GILDO
  • NATTA, Andrea

Dates

Publication Date
20260513
Application Date
20190725

Claims (15)

  1. Tyre (1) comprising a monitoring device (10) fixed on an inner surface (15) of said tyre (1) at a crown portion (16) of said tyre (1), wherein the monitoring device (10) comprises an electronic unit (11) and an electric power supplier (12) electrically connected to said electronic unit (11), the electronic unit (11) comprising: at least one sensor for detecting at least one of the following physical quantities: temperature, pressure, acceleration, deformation; a processing unit; and a transceiver, wherein the monitoring device (10) further comprises a flexible support (13) in a single body, the electronic unit (11) being fixed onto said flexible support (13), wherein said electric power supplier (12) comprises a plurality of electric energy accumulators (14), each accumulator (14) being electrically connected to said electronic unit (11) and suitable for supplying said electronic unit (11), wherein each of said accumulators (14) is fixed onto said flexible support (13), characterized in that each of said accumulators (14) has a charge capacity greater than or equal to 30 mAh, a weight greater than or equal to about 0.5 g, and it is inscribed in a circle having diameter lower than or equal to 30 mm, and circumscribed to a circle having diameter greater than or equal to 15 mm, and in that a distance (D) between each pair of accumulators (14) is greater than or equal to 40 mm and lower than or equal to 250 mm.
  2. Tyre (1) according to claim 1, wherein each of said accumulators (14) is an electric battery and comprises a rigid housing.
  3. Tyre (1) according to any one of the previous claims, wherein the monitoring device (10) comprises an electric connection circuit (18) for connecting each accumulator (14) to said electronic unit (11), wherein said electric connection circuit (18) comprises at least two separate electric paths, wherein said accumulators (14) are electrically connected to said electronic unit (11) in parallel, and wherein the electric connection circuit (18) is printed onto said flexible support (13) with a conductive ink or the electric connection circuit (18) comprises copper conductive tracks.
  4. Tyre (1) according to any one of the previous claims, wherein an equatorial plane (20) of the tyre crosses said monitoring device (10), preferably it crosses said electronic unit (11).
  5. Tyre (1) according to any one of the previous claims, wherein said at least one sensor is suitable for detecting at least a radial component and/or a tangential component of said acceleration and/or of said deformation, and wherein said flexible support (13) is fixed to the inner surface (15) of said tyre (1) by means of a layer of adhesive.
  6. Tyre (1) according to any one of the previous claims, wherein said flexible support (13) is substantially inextensible.
  7. Tyre (1) according to any one of the previous claims, wherein said flexible support (13) is a film of an elastomeric or thermoplastic material selected from the following group: nylon, PET, PEN, polyimide, EPDM, diene polymers and polyurethane resins.
  8. Tyre (1) according to any one of the previous claims, wherein at least two among said sensor, said processing unit and said transceiver are arranged in a single assembly fixed onto said flexible support (13), wherein said plurality of accumulators (14) comprises a first and a second accumulator (14) arranged at opposite sides of said electronic unit (11), and wherein said monitoring device (10) has a plan with elongated shape along a longitudinal direction (L) of main development, wherein said first and second accumulators (14) are arranged at longitudinally opposite ends of the monitoring device (10).
  9. Tyre (1) according to any one of the previous claims, wherein the monitoring device (10) is fixed to the inner surface (15) of the tyre (1) so that a straight line passing through the centres of mass of the accumulators (14) forms, with a direction of intersection (20') of the equatorial plane (20) with the inner surface (15) of the tyre (1), a right angle (A) or an acute angle (A) greater than or equal to 20°, wherein said acute angle (A) is lower than or equal to 70°.
  10. Tyre (1) according to any one of the previous claims, wherein an aspect ratio (R) between a longitudinal length (L1) of the monitoring device (10) and a width (L2) along a direction perpendicular to the longitudinal direction is greater than or equal to 2 and/or lower than or equal to 6.
  11. Tyre (1) according to any one of the previous claims, wherein said plurality of accumulators (14) comprises two and no more than two accumulators (14).
  12. Tyre (1) according to any one of the claims from 1 to 11, wherein said plurality of accumulators (14) comprises at least a third accumulator (14).
  13. Tyre (1) according to claim 12, wherein said plurality of accumulators (14) comprises a fourth accumulator (14).
  14. Tyre (1) according to claim 12 or 13, wherein said accumulators (14) are arranged substantially angularly equidistant from each other around said electronic unit (11).
  15. Tyre (1) according to any one of the previous claims, wherein said accumulators (14) are arranged at end positions of said flexible support (13).

Description

Technical field of the invention The present invention relates to a tyre comprising a monitoring device, for example suitable for monitoring at least one physical quantity among temperature, pressure, deformation, acceleration. State of the art Typically a tyre has a substantially toroidal structure around an axis of rotation of the same during operation, and it has an equatorial plane orthogonal to the axis of rotation, said equatorial plane being typically a plane of (substantial) geometric symmetry (e.g. ignoring any minor asymmetries, such as the tread design and/or the writing on the sides and/or structure or profile asymmetries). With "inner cavity" it is meant the space delimited by the inner surface of tyre and by the surface of the rim facing towards the inner surface of the tyre, when mounted. With "crown portion" it is meant the portion of tyre placed between the two sides of the tyre, i.e. at the position of the tread band. The terms "radial" and "axial" are used with reference respectively to a substantially perpendicular direction and to substantially parallel direction to the rotation axis of the tyre. The term "tangential" is used with reference to a direction generally faced according to the rolling direction of the tyre, substantially perpendicular to both the radial direction and the axial direction. With "footprint" it is meant the portion of outer surface of the tread band which, during the rolling of the tyre mounted and subjected to a load (for example due to effect of the mounting under a vehicle), at each instant is in contact with the rolling surface. The footprint typically has a substantially null curvature (or substantially infinite curvature radius), or in each case it substantially assumes the conformation of the rolling surface. There have been proposed tyres for vehicles comprising monitoring devices of one or more physical quantities arranged in the inner cavity of the tyre, for example as described in US 2014/0118134 A1; US 4,862,486; US 5,749,984; US 5,960,844; US 5,977,870; US 2008/0303634 A1; US 2009/0134710 A1; US 2010/0007477 A1, DE 102012007071 A1, WO2007/121768 A1, WO2007/048621 A1, WO2013/098711 A1, WO2013/098712 A1, WO2018/065846 A1, US 2007/0013503 A1, US 2010/0097662 A1, WO2016042580A1, DE102007014097A1, DE102005051136A1. Summary of the invention In the context of tyres comprising monitoring devices arranged in the inner cavity of the tyre, the Applicant has made the following considerations. It is preferable to detect the desired physical quantity, in particular the temperature, the deformation or the acceleration, directly onto the, or near to the, inner surface of the tyre at its crown portion. For example, it is preferable to acquire the temperature near to the inner surface of the crown portion, since in this way it is substantially acquired the actual temperature of the tyre material in the area in which the greatest stresses develop, which tend to heat the tyre during the rolling. On the contrary, the temperature for example near to the rim or the temperature of the fluid present in the inner cavity can be very different from the temperature of the inner surface of the crown portion. Moreover, when the temperature is obtained, for example near to the rim or the inflation valve, the data measured is influenced by the temperature of the environment outside the wheel due to the heat conduction and/or the presence of external heat sources such as air flows from the radiators or the brake discs. In the case of the acceleration or of the deformation, it is preferable a direct measurement of at least one of the radial, tangential and axial components of the acceleration or of the deformation undergone by an arbitrary point located onto the inner surface of the crown portion which is subjected to stress and deformation due to the cycle of entry and exit from the footprint, or more generally from the interaction between the tyre and the rolling surface. In this way it is possible to obtain from the detected acceleration or deformation signal information on the status and/or instantaneous behaviour of the tyre during use (e.g. size of the footprint, wear, hydroplaning, slippage, etc.). Therefore it is desirable to apply the acceleration and/or deformation sensor, or the sensors, to a point close to where the greatest stresses are generated, i.e. near to the contact between the tyre and the rolling surface, as typically a point on the inner surface of the crown portion for example placed in correspondence with the central rib arranged in the axially central area of the tread, or in any case in a point on the inner surface of the crown portion corresponding to the most stressed area (both mechanically and thermally) of the tread during the tyre rolling. For the realization of the monitoring device a PCB ('Printed Circuit Board') technology is typically used, based on a rigid support, on which the circuit tracks (electrically conductive metal tracks) are printed and t