A pneumatic radial tire for passenger vehicles of the present disclosure includes a carcass toroidally spanning between a pair of bead portions and including plies of radially arranged cords. A sectional width SW (mm) and an outer diameter OD (mm) of the tire satisfy a predetermined relational expression. At least one noise reducer is provided on an inner surface of the tire. The noise reducer is provided at least in the center region and the shoulder region. Among thicknesses of the noise reducer measured in a direction perpendicular to the inner surface of the tire, a maximum thickness Ts in the shoulder regions is larger than a maximum thickness Tc in the center region.

A pneumatic radial tire for passenger vehicles of the present disclosure includes a carcass toroidally spanning between a pair of bead portions and including plies of radially arranged cords. A sectional width SW (mm) and an outer diameter OD (mm) of the tire satisfy a predetermined relational expression. At least one noise reducer is provided on an inner surface of the tire. The noise reducer is provided at least in the center region and the shoulder region. Among thicknesses of the noise reducer measured in a direction perpendicular to the inner surface of the tire, a maximum thickness Ts in the shoulder regions is larger than a maximum thickness Tc in the center region.

In a pneumatic tire, at least one carcass layer mounted between a pair of bead portions is formed from a carcass cord formed of an organic fiber cord having filament bundles of organic fibers intertwined together, a fineness based on corrected mass of the carcass cord is from 4000 dtex to 8000 dtex, an intermediate elongation of the carcass cord at a sidewall portion under 1.0 cN/dtex load is from 3.3% to 4.2%, and a ratio G/R of an interlayer rubber gauge G between a body portion and a folded back portion to a cord diameter R of the carcass cord, at a contact region where the body portion and the folded back portion are in contact in the carcass layer, is from 0.50 to 0.60.

In a pneumatic tire, at least one carcass layer mounted between a pair of bead portions is formed from a carcass cord formed of an organic fiber cord having filament bundles of organic fibers intertwined together, a fineness based on corrected mass of the carcass cord is from 4000 dtex to 8000 dtex, an intermediate elongation of the carcass cord at a sidewall portion under 1.0 cN/dtex load is from 3.3% to 4.2%, and a ratio G/R of an interlayer rubber gauge G between a body portion and a folded back portion to a cord diameter R of the carcass cord, at a contact region where the body portion and the folded back portion are in contact in the carcass layer, is from 0.50 to 0.60.

The present invention relates to a tire including an aramid cord in the carcass layer, the tire including a carcass layer including a multi-filament aramid cord. The tire of the present invention can maintain the performance of existing performance of tires for trucks and buses by ameliorating weak fatigue resistance while enhancing the fuel efficiency through weight reduction of the carcass cord.

A multi-strand cord (50) comprises an internal layer (CI) of the cord made up of K=1 two-layer (C1, C3) internal strand (TI), with the internal layer (C1) being made up of Q internal metallic threads (F1), and the external layer (C3) being made up of N external metallic threads (F3), and an external layer (CE) of the cord made up of L>1 two-layer (C1′, C3′) external strands (TE) wound around the internal layer (CI) of the cord, with the internal layer (C1′) being made up of Q′ internal metallic threads (F1′), and the external layer (C3′) being made up of N′ external metallic threads (F3′). The cord (50) has an endurance criterion SL≤40 000 MPa.Math.mm with

[00001]$SL=\max \left(\frac{\Delta {\sigma }_{\mathrm{bending\_CI}}}{\mathrm{Cp}};\frac{\Delta {\sigma }_{\mathrm{bending\_CE}}}{C_r\times \mathrm{Cp}}\right)$

and a size criterion Ec≥0.46 with Ec=Sc/Se.

A multi-strand cord (50) comprises an internal layer (CI) of the cord made up of K=1 two-layer (C1, C3) internal strand (TI), with the internal layer (C1) being made up of Q internal metallic threads (F1), and the external layer (C3) being made up of N external metallic threads (F3), and an external layer (CE) of the cord made up of L>1 two-layer (C1′, C3′) external strands (TE) wound around the internal layer (CI) of the cord, with the internal layer (C1′) being made up of Q′ internal metallic threads (F1′), and the external layer (C3′) being made up of N′ external metallic threads (F3′). The cord (50) has an endurance criterion SL≤40 000 MPa.Math.mm with

[00001]$SL=\max \left(\frac{\Delta {\sigma }_{\mathrm{bending\_CI}}}{\mathrm{Cp}};\frac{\Delta {\sigma }_{\mathrm{bending\_CE}}}{C_r\times \mathrm{Cp}}\right)$

and a size criterion Ec≥0.46 with Ec=Sc/Se.

A tyre for vehicle wheels includes a carcass structure with at least one carcass ply formed by strip-like elements consecutively adjacent one after the other along a circumferential extension and having overlap zones along respective longitudinal edges superimposed on each other. Each overlap zone has, along a longitudinal extension thereof, terminal sections that are laterally opposite with respect to an intermediate section. The intermediate section of each overlap zone has an intermediate overlap width greater than a terminal overlap width of the terminal sections.

A tyre for vehicle wheels includes a carcass structure with at least one carcass ply formed by strip-like elements consecutively adjacent one after the other along a circumferential extension and having overlap zones along respective longitudinal edges superimposed on each other. Each overlap zone has, along a longitudinal extension thereof, terminal sections that are laterally opposite with respect to an intermediate section. The intermediate section of each overlap zone has an intermediate overlap width greater than a terminal overlap width of the terminal sections.

A tire for a civil engineering vehicle the endurance of which has been improved by the addition of an anti-creep layer (30) with a thickness E2 interposed between the airtight inner layer (20), with a thickness E1, and the reinforcer coating layer (46) of the carcass reinforcement (40), with a thickness E3. The thicknesses E1, E2 and E3, being measured in millimetres in a shoulder region forming the transition between the crown and each sidewall of the tire, satisfy the following equations: 2≤E1≤4; 6≤E2+E3 and E1/E2≥0.6. In addition, the viscoelastic loss P60 of the elastomeric mixture M2 of the anti-creep layer (30) is at most equal to 20%.