| 摘要 |
<p>A heavy duty radial tyre (1) has a carcass (6) including a carcass ply made of cords arranged at an inclination angle of 70 to 90 degrees with respect to the tyre equator, the carcass ply comprising a main portion (6A) extending from a tread portion (2) to a bead core (5) in a bead portion (4) through a sidewall portion (3) and integrally provided with a turnup portion (6B) turned up from the axially inside to the outside at the bead core (5) to extend radially outwards, and a bead apex (8) disposed between the main portion (6A) and turnup portion (6B) of the carcass ply and tapering and extending radially outwardly from the bead core (5), characterised in that the above-mentioned turnup portion (6B) extends radially outwardly along the axially outer surface of the bead apex (8) and has a parallel portion extending substantially parallel with and adjacently to the carcass ply main portion (6A) from the radially outer end (8t) of the bead apex, and the length L of the parallel portion is 1.0 to 8.0 times the maximum section width CW of the bead core (5). <IMAGE></p> |
