| 摘要 |
PURPOSE:To improve the uniformity and high speed durability by interposing a carcass reinforcement ply having the cord angle of nearly zero relative to the circumferential direction of tire between the carcass ply and the innermost belt ply so that a perpendicularly intersecting net structure may be formed in cooperation with the carcass ply cords. CONSTITUTION:A carcass reinforcement ply 7 in which nylon cords etc. are so arranged that the cord angle is nearly zero relative to the circumferential direction EE' of tire is interposed between the carcass ply 4 and the innermost ply 5' of belt plies 5 so that a net structure may be formed in which cords of the carcass ply 4 and cords of the carcass reinforcement ply 7 intersect perpendicularly. In this constitution, since the primary direction of elasticity of both the plies 4, 7 corresponds respectively with the direction of the tire section and the direction of the tire circumference that intersect perpendicularly with each other, the change of the cord angle of carcass cords due to the pantograph effect of the tire can be prevented. Therefore, the tire's uniformity and high speed durability can be improved. |
