| 摘要 |
PURPOSE:To increase the inclination of the surface of a tread section to greatly enhance the anti-skid ability of a tire, by setting the height of radial ribs from the groove bottom to more than 4mm. and by making the heights thereof different at every other rib or every plural number rib. CONSTITUTION:A tread section 1 has radial narrow ribs 2, 3, and is stepped. Further, the heights of radial narrow ribs, even lowest one, are required to be more than 4mm. since, if they are more than 4mm., the rigidity of the tread section 1 as a whole would become insufficient so that the gripping force of the tire upon running on a curved road becomes insufficient to incurr instability in control. |
