| 摘要 |
<p>A heavy duty radial tyre of improved bead durability wherein the bottom face of the bead (3) has an axially inner face Si and an axially outer face So each tapered axially inwardly to decrease the diameter of the bottom face, the taper in the inner face Si is greater than that of the outer face So, the boundary (LS) between) the inner face Si and the outer face So is located axially inwardly of the centre of gravity (G) of the bead core (2) and when the tyre is mounted on its regular rim and inflated to its regular pressure, the axial distance X of the axially inner edge Q2 of the bead core (2) from a bead heel Q1 defined as the intersection between a rim base line B and an extending line of the inner surface of a rim flange (9f) of the rim is not less than 80% and not more than 105% of the height HR of the radially outer edge Q3 of the rim flange (9f) from the rim base line (B); and the radial distance Y of the radially outer edge Q4 of the bead core (2) measured radially inwardly from the radially outer edge Q3 of the rim flange (9f) is not less than 0% and not more than 30% of the height HR of the rim flange (9f) from the rim base line (B).</p> |
