| 摘要 |
<p>A heavy-duty radial tire comprising a carcass layer (3), a tread (2), and a belt layer (4) provided between the carcass layer (3) and the tread (2), the belt layer (4) comprising at least four metallic cord layers of first, second, third, and fourth belts (4a, 4b, 4c, 4d) in that order from the carcass layer (3) towards the tread (4), wherein the first belt (4a) has a cord angle of 40 DEG to 75 DEG relative to the circumferential direction of the tire and is split into left and right portions so as to provide a space (G) in the central region of a crown portion, the left and right portions being provided on left and right shoulder portions (S), respectively; the space (G) is provided with either at least one organic fiber cord layer (5) having a total tensile strength per unit width of at least 240 kgf/cm and a cord angle of 0 DEG to 10 DEG relative to the circumferential direction of the tire or an inextensible fiber cord layer having a two-layer structure wherein the sum of the tensile moduli per unit width in the initial tension of all the cords is at least 1.3 x 10<3> kgf/cm, the cord angle is larger than 0 DEG and two layers in the two-layer structure cross each other at an absolute angle smaller than the cord angle of the second and third belts (4b, 4c); the second belt (4b) comprises cords provided at a cord angle of 22 DEG to 30 DEG relative to the circumferential direction of the tire; the third belt (4c) comprises cords crossing the cords constituting the second belt (4b) and provided at a cord angle of 10 DEG to 16 DEG relative to the circumferential direction of the tire, and the fourth belt (4d) comprises cords provided at a cord angle of at least 18 DEG relative to the circumferential direction of the tire.</p> |
