| 摘要 |
PURPOSE:To improve high-speed durability, steering stability, resistance to shock, and such in a flat tire that uses a hold belt layer by specifying tire flattening and forming a bead reinforced layer with specific structure including a specific bead apex. CONSTITUTION:The ratio of the maximum tire width W and the tire cross-sectional height H (H/W) is set to 52-70% and the ratio of the tread width TW to the maximum width W (TW/W) is set to 60-78%. In addition, a carcass folding section 7a is located in the vicinity of the maximum width position of a side wall section and a folding section 8a is located lower than the folding section 7a. A bead apex 4 with the modulus of elasticity exceeding 350kg/cm<2> is arranged at the upper part of a bead core 3 enclosed by the folding sections 7a and 8a. Furthermore, a reinforced layer 5 with the higher modulus of elasticity than a carcass cord is arranged at the outside of the bead apex 4. As a result, high-speed durability, steering stability, resistance to shock, and comfortability to drive can be improved. |
