Tire comprising a carcass reinforcement made up of two layers
AssigneesCompagnie Generale Des Etablissements Michelin, Michelin Recherche et Technique S.A.
InventorsMarc Francia, Yves Potin, Florian Vilcot
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AssigneesCompagnie Generale Des Etablissements Michelin, Michelin Recherche et Technique S.A.
InventorsMarc Francia, Yves Potin, Florian Vilcot
Estimating the term…
The tire has a load index that is at least 118 and two layers of reinforcing elements. Each of the layers has a breaking force per unit width that is higher than 2900 daN/dm. A minimum strength per unit width, measured for an elongation of less than 10%, of the second layer is greater than 20% of the minimum strength per unit width, measured for an elongation of less than 10%, of the first layer. The reinforcing elements of the first layer have a thread count that is higher than 300 tex. The reinforcing elements of the two layers have a thread count of less than 750 tex. The elongation of the reinforcing elements of the second layer are greater than 8% under a force of 20 daN and the secant elastic modulus values under tension at 10% elongation, Mt, Mj, satisfy the relationship Mt/Mj≥1.
A tire with radial carcass reinforcement, having a load index higher than or equal to 118, comprising a crown reinforcement, itself capped radially by a tread, the said tread being connected to two beads, comprising a bead wire, by two sidewalls, the said carcass reinforcement being made up of two layers of textile reinforcing elements, a first layer of carcass reinforcement being turned up around the bead wire in each of the beads, the ends of the said first layer of carcass reinforcement being radially on the outside of the radially outermost point of the bead wire in each bead and the second layer of carcass reinforcement extending from one bead to the other without any turnup around the bead wire in each of the beads, its ends being axially on the outside of the axially outermost point of the bead wire in each bead, the said tire comprising in each sidewall a first filling element, axially on the inside of the exterior surface of a sidewall and axially on the outside of the turnup of the first layer of carcass reinforcement, and made of a rubber compound having a secant elastic modulus under tension at 10% elongation of Mj, each bead comprising a second filling element made of a rubber compound having a secant elastic modulus under tension at 10% elongation of Mt, extending the bead wire core radially towards the outside, wherein each of the layers of carcass reinforcement has a breaking force per unit width higher than 2900 daN/dm, wherein the minimum strength per unit width, measured for an elongation of less than 10%, of the second layer of carcass reinforcement is strictly greater than a value equal to 20% of the minimum strength per unit width, measured for an elongation of less than 10% of the first layer of carcass reinforcement, in that the reinforcing elements of the first layer of carcass reinforcement have a thread count higher than 300 tex, wherein the reinforcing elements of the two layers of carcass reinforcement have a thread count of less than 750 tex, wherein the elongation of the reinforcing elements of the second layer of carcass reinforcement is greater than 8% under a force of 20 daN and wherein the secant elastic modulus values under tension at 10% elongation, Mt, Mj, satisfy the relationship Mt/Mj≥1, wherein, in a meridian plane, in each bead, the tire comprises a layer of reinforcing elements made of aromatic polyamide in contact with the said first layer of carcass reinforcement over the entire length thereof, at least a part being radially on the inside of the bead wire and of which the ends are radially on the outside of the geometric center of the bead wire, and wherein the said first layer of carcass reinforcement is interposed between the bead wire and the layer of reinforcing elements made of aromatic polyamide.
Dependencies are inferred from the claim text.