| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To elongate the life of a tire by improving the fatigue life caused by the structure of this kind of a steel cord while considering reduction of a fuel cost/saving of resources. <P>SOLUTION: The fatigue resistance is improved in the steel cord having a three-layer structure obtained by twisting each layer of a core, a sheath and a cord having the same wire diameters in the same direction by regulating the intersection angle (θ<SB>C</SB>-θ<SB>S</SB>) of the twist angleθ<SB>S</SB>of the sheath wire, and the twist angleθ<SB>C</SB>of the cord wire so as to satisfy the expression: -3.0°≤θ<SB>C</SB>-θ<SB>S</SB>≤3.0°to extremely reduce the fretting abrasion between the sheath and the cord. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
