| 摘要 |
PURPOSE:To ensure steering stability while enhancing a reduction in weight by forming one of two belt layers from an aramid fiber cord and the other from a steel cord, making the tread groove depth and groove under rubber layer thickness smaller than in the past, and specifying the wire total sectional area per unit width of the steel cord belt layer. CONSTITUTION:On the outside of a carcass layer 2, two belt layers consisting of an inside belt layer 4d and an outside belt layer 4u are disposed. The outside belt layer 4u is formed from an aramid fiber cord, and the inside belt layer 4d from a steel cord, and the steel wire total sectional area alpha per 50mm width is 5-14m<2>. On the surface of a tread 1, a main groove 6 extending in tire circumferential direction EE' is provided. The main groove depth is set to 6.0-8.5mm, the groove under rubber thickness (t) to 0.5-2.5mm. Thus, cornering power can be equalized to or made higher than that in a conventional tire, and a lighter weight can be also realized. |
