| 摘要 |
An improvement is provided in a pneumatic safety tire having a pair of bead portions with a bead core, sidewall portions extending radially outward one from each of the bead portions, a tread portion extending between the sidewall portions, the tread portions being disposed outward of the carcass, a toroidal carcass extending through the tread and sidewall portions and turned up at the both edges around the bead cores, a belt disposed between the carcass and the tread and having cords laid at a relatively small angle relative to the equator of the tire, and a sidewall reinforcing layer disposed inward of the carcass in each sidewall portion. There are particularly specified relationships in these parts of the tire, i.e.: the thickness of each sidewall gradually increases towards a 65% height point; the difference between the thickness at the 65% height point and the minimum thickness is particularly specified; each sidewall portion gradually increases in thickness from the 65% height point toward the maximum width portion; each sidewall portion gradually increases in thickness from the maximum width position toward a contact position; the thickness at the contact position is larger than the thickness at the maximum width position; the difference between the thickness at the contacting position and the thickness at the maximum width position is particularly specified; and the sidewall reinforcing layer is a crescent-shaped, three-layered structure in which a hard rubber strip having a specified Shore A hardness and 100% modulus is sandwiched between soft rubber strips, each having a specified Shore A hardness and 100% modulus. |
