US 12,138,972 B2
Tire for a heavy civil-engineering vehicle with a simplified crown reinforcement
Emmanuel Clement, Clermont-Ferrand (FR); and Sylvie Lhospitalier, Clermont-Ferrand (FR)
Assigned to COMPAGNIE GENERALE DES ETABLISSEMENTS MICHELIN, Clermont-Ferrand (FR)
Appl. No. 17/628,799
Filed by COMPAGNIE GENERALE DES ETABLISSEMENTS MICHELIN, Clermont-Ferrand (FR)
PCT Filed Jul. 7, 2020, PCT No. PCT/FR2020/051205
§ 371(c)(1), (2) Date Jan. 20, 2022,
PCT Pub. No. WO2021/014065, PCT Pub. Date Jan. 28, 2021.
Claims priority of application No. 1908339 (FR), filed on Jul. 23, 2019.
Prior Publication US 2022/0371369 A1, Nov. 24, 2022
Int. Cl. B60C 9/18 (2006.01); B60C 9/00 (2006.01); B60C 9/28 (2006.01)
CPC B60C 9/18 (2013.01) [B60C 9/0007 (2013.01); B60C 2009/0021 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A tire for a heavy-duty vehicle, the tire comprising:
a nominal section B within the meaning of the European Tyre and Rim Technical Organisation (ETRTO) standard;
a tread;
a carcass reinforcement; and
a crown reinforcement radially on an inside of the tread and radially on an outside of the carcass reinforcement, the crown reinforcement including:
at least one low-modulus layer formed of low-modulus elastic metal reinforcers, which are coated in an elastomeric material, the low-modulus reinforcers being mutually parallel and forming an angle Alpha1 with a circumferential direction tangential to a circumference of the tire, the low-modulus reinforcers having a structural elongation at least equal to 0.4% and a total elongation at break at least equal to 3%, and the tensile elastic modulus of the low-modulus reinforcers being between 40 GPa and 130 GPa;
a rigid layer formed of rigid metal reinforcers, which are coated in an elastomeric material, the rigid metal reinforcers being mutually parallel and forming an angle Alpha2 with the circumferential direction tangential to the circumference of the tire, the structural elongation of the rigid metal reinforcers being less than or equal to 0.2%, and the tensile elastic modulus of the rigid reinforcers being between 140 GPa and 200 GPa; and
a triangulation layer comprising metal reinforcers, which are coated in an elastomeric material, the metal reinforcers being mutually parallel and forming an angle Beta with the circumferential direction tangential to the circumference of the tire,
wherein the angle Beta is greater than or equal to 50° in terms of absolute value,
wherein a breaking tension of the rigid layer is greater than or equal to 120 daN/mm,
wherein a ratio of the breaking tension of the rigid layer to that of the at least one low-modulus layer is greater than or equal to 1.2,
wherein the breaking tension of the at least one low-modulus layer is greater than or equal to 80 daN/mm,
wherein an axial width of the at least one low-modulus layer is greater than an axial width of the rigid layer by a distance DNT at least equal to 10 mm at each axial end, and
wherein at least one low-modulus layer is in contact with the rigid layer over an axial width W at least equal to 20% of the nominal section B of the tire and the triangulation layer is positioned on an inside of the rigid layer and in contact therewith in the radial direction.