| 摘要 |
PROBLEM TO BE SOLVED: To prevent the shimmy in high frequency area and stabilize the steering in high-speed traveling by arranging a bead filler having a specified hardness on the tire axial outside of the turn-up part of an up-ply carcass. SOLUTION: An up-ply carcass 4 consists of a ply of organic fiber cords arranged in one direction within the range of 60-90 deg. to the tire equatorial surface, and both ends thereof are reinforced by turning up it from the inside of a bead core 3 toward the outside. A bead filler 6 has a hardness of 60-99 deg. by Shore hardness, and arranged on the tire axial outside of the turn-up part of the up-ply carcass 4. The hardness of the bead filler 6 is set to this range, whereby sufficient steering performance can be ensured in a pneumatic tire of a flexible structure having a spiral belt. Particularly, not only the shimmy that is becoming tangible according to the lighter weight and higher performance of vehicle can be reduced, but also the steering stability can be improved. |
