| 摘要 |
<p>An of object of the present invention is to provide a pneumatic tire which exhibits improved durability of a bead portion due to further suppressing compression strain at a carcass ply fold-up portion and, in particular, suppressing fatigue fracture at the carcass ply fold-up portion. Cord distance between the carcass main body and the carcass ply fold-up portion gradually decreases from the bead core toward the outer side in the tire radial direction to reach the minimum value a, then gradually increases to the maximum value b; provided that height H f of a flange of an application rim, measured from a base line of the application rim in a state where the tire is assembled with the rim and inflated at a prescribed internal pressure, is 1, heights H A and H B measured from the base line to the positions on the carcass main body corresponding to the minimum and the maximum values, respectively, and the maximum height H T of the tire satisfy relationship formulae below,
H T ‰¥ 8.00
1.26 ‰¤ H A ‰¤ 2.14
2.43 ‰¤ H B ‰¤ 3.75; and
a value of ratio (b/a) of the maximum value b with respect to the minimum value a of distance between cords of the carcass main body and the carcass ply fold-up portion exceeds 1.00.</p> |
