| 摘要 |
PURPOSE:To augment resistance to fatigue by allowing the twist angle of a center layer to be larger than that of outer layers where each of layers is composed of numbers of steel filaments so as to form each of respective steel cords, while the twist angle is larger than the specified angle. CONSTITUTION:A neumatic tire is composed of steel cords. The steel cords are composed of a center layer 1, an intermediate layer 2, and an outer layer 3. The center layer is made of more than two steel filaments twisted together, the intermediate layer is made of numbers of steel filaments twisted together surrounding the center layer, and the outer layer is also made of numbers of steel filaments twisted together surrounding the intermediate layer 2. Each of steel filaments which form the layer 1 through 3, is twisted together so as to make the twist angle theta1 through theta2 to the axial direction of the cord. The twist angle theta1 through theta2 of each of layers 1 through 3 are set to be larger than 10 deg. while the relation among the angles is to be an inequality of theta1>theta2>theta3. |
