Tyre monitoring device comprising an electronic unit and tyre comprising said device
A tyre monitoring device with an electronic unit enclosed in an encapsulation material. The encapsulation material forms a single body with an upper portion and a lower portion. The upper portion encloses and protects the electronic unit and the lower portion has a base surface aimed at fixing said device to the inner surface of the tyre.
1. A tyre monitoring device, comprising an electronic unit at least partially enclosed in an encapsulation material, the device comprising:
a lower portion having a base surface for fixing the device to an inner surface portion of the tyre; and
an upper portion arranged on an opposite side of the device with respect to the base surface, and the upper portion encloses at least part of the electronic unit;
wherein:
the encapsulation material is comprised in both the lower portion and the upper portion;
the encapsulation material of the lower portion and the upper portion is in continuity to form a single body;
the lower portion has an outermost portion, and the encapsulation material of the lower portion is located at least at the base surface and the outermost portion;
the upper portion has an area smaller than an area of the base surface of the lower portion;
the area of the base surface of the lower portion is equal to at least 300% of the area of the upper portion; and
the encapsulation material directly contacts at least a portion of a battery of the electronic unit.
2. The device according to claim 1 , wherein the lower portion comprises a plurality of reinforcing elements.
3. The device according to claim 2 , wherein the reinforcing elements comprise textile filaments, textile cords, metallic filaments, or metallic cords.
4. The device according to claim 3 , wherein the textile filaments or cords are made of one or more of the following textile materials chosen from: aramid, rayon, polyester, nylon, lycocell, and combinations thereof.
5. The device according to claim 2 , wherein the reinforcing elements are arranged in the lower portion with a density comprised between 30 cords/dm and 500 cords/dm.
6. The device according to claim 2 , wherein the reinforcing elements are further associated with or incorporated in the encapsulation material.
7. The device according to claim 6 , wherein the reinforcing elements are incorporated in a layer of elastomeric material coupled to the encapsulation material.
8. The device according to claim 1 , wherein the upper portion has a substantially prismatic or cylindrical shape with a circular or oval base.
9. The device according to claim 1 , wherein the lower portion has a circular or oval shape.
10. The device according to claim 1 , wherein the upper portion comprises a rigid body enclosing at least part of the electronic unit and at least part of the encapsulation material.
11. The device according to claim 1 , wherein the encapsulation material is a polyurethane material or a polyurea.
12. The device according to claim 11 , wherein the encapsulation material is a polyether-based polyurethane material.
13. The device according to claim 12 , wherein the polyether-based polyurethane material has International Rubber Hardness Degrees (IRHD) hardness at 100° C. greater than 60.
14. The device according to claim 13 , wherein the polyether-based polyurethane material has IRHD hardness at 100° C. less than 90.
15. The device according to claim 1 , wherein the outermost portion of the lower portion has a thickness of less than 1.0 mm.
16. The device according to claim 15 , wherein the outermost portion of the lower portion has a thickness greater than 0.1 mm.
17. The device according to claim 1 , wherein the encapsulation material of the lower portion is connected to the encapsulation material of the upper portion through one or more connecting portions having a radius of curvature of not less than 0.5 mm.
18. The device according to claim 17 , wherein the radius of curvature is not greater than 10 mm.
19. The device according to claim 1 , wherein the lower portion has a thickness of less than 5 mm and greater than 0.1 mm.
20. The device according to claim 1 , wherein the upper portion has a minimum thickness of not less than 5 mm.
21. The device according to claim 20 , wherein the minimum thickness is not greater than 20 mm.
22. The device according to claim 1 , wherein the base surface comprises an adhesive layer suitable for gluing to the inner surface portion of the tyre.
23. The device according to claim 22 , wherein the adhesive is a pressure sensitive adhesive, a structural adhesive, or a combination thereof.
24. A tyre comprising an inner surface and a monitoring device, the monitoring device comprising an electronic unit encapsulated in an encapsulation material, the device comprising:
a lower portion having a base surface for fixing the device to an inner surface portion of the tyre; and
an upper portion arranged on an opposite side of the device with respect to the base surface, and the upper portion encloses at least part of the electronic unit;
wherein:
the encapsulation material is comprised in both the lower portion and the upper portion;
the encapsulation material of the lower portion and the upper portion is in continuity to form a single body;
the lower portion has an outermost portion, and the encapsulation material of the lower portion is located at least at the base surface and the outermost portion;
the upper portion has an area smaller than an area of the base surface of the lower portion;
the area of the base surface of the lower portion is equal to at least 300% of the area of the upper portion; and
the encapsulation material directly contacts at least a portion of a battery of the electronic unit.
25. The tyre according to claim 24 , wherein the device is fixed to a portion of the inner surface opposite to a tread of the tyre.