Radial vehicle tire
AssigneeSocieta' Pneumatici Pirelli S.p.A.
InventorMario Mezzanotte
Life of this patent
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Abstract
This invention provides a pneumatic tire for vehicle wheels having a carcass, a tread and a breaker structure. The breaker structure has at least two layers of parallel cords at an angle of 10.degree.-35.degree. and made of a material having a tensile strength of at least 260 kg/mm.sup.2. The cords of one layer are crossed with respect to those of the adjacent layer. The breaker structure also has at least one strip of textile cords made of a material which shrinks in length when heated. The tire also has in each sidewall, a reinforcing element of at least one layer of textile or metal cords inclined with respect to the circumferential lines of the tire and at least two layers of cords parallel to each other in each layer and crossed with respect to those of the adjacent layer.
Claims10
A pneumatic tire for vehicle wheels which comprises a carcass comprising at least one layer of cords laying in substantially radial planes, a tread, a breaker arranged between said carcass and said tread and comprising at least two layers of cords made of a material having a tensile strength of at least 260 kg/mm.sup.2, said cords being parallel to one another in each layer and crossed with respect to those of the adjacent layer and forming an angle ranging between 10.degree. and 35.degree. with respect to the equatorial plane, and at least one strip of textile cords made of a material which shrinks in length when heated, said textile cords being parallel to the equatorial plane and being arranged in a radially outermost position with respect to said layers, said tire comprising, in each sidewall, a reinforcing element comprising at least one layer of reinforcing cords inclined with respect to the circumferential lines of the tire, said reinforcing element extending radially at least from the zone axially adjacent the bead core to a point where its radially outer portion is disposed between said layers and said breaker strip, that portion of said reinforcing element which is disposed between said layers and said strip having a width ranging between 5% and 30% of the breaker width, said reinforcing element being arranged in an axially outermost position with respect to the carcass, said tire being characterized in that it further comprises, in each sidewall at least two layers of cords parallel to each other in each layer and crossed with respect to those of the adjacent layer, said cords forming an angle ranging from 30.degree. to 65.degree. with respect to the circumferential lines, said two layers being arranged between said carcass and said reinforcing element and extending radially from the zone axially adjacent the bead core as far as to extend with their radially outer portion between said carcass and said breaker layers, and in that said reinforcing element has its cords inclined at an angle ranging from 25.degree. to 90.degree..
Dependencies are inferred from the claim text.