| 摘要 |
PURPOSE:To make improvements in high-speed durability and abrasion resis tance, by constituting a tire in specifying both notch volumetric and circumferen tial rigid indexes, in case of the above-captioned tire for a bus or the like which partitions off a tread part into a central part and a shoulder part with a main groove and installs a narrow notch in this shoulder part. CONSTITUTION:A tread 1 is partitioned off into a crown part CR of 30-65% of tread width TW and a shoulder part SH centering on a tire equatorial surface C with zigzag, deep-grooved vertical main grooves G1 and G2 extending in a longitudinal direction. And, vertical small grooves g1 and g2 are installed in this crown part CR in addition, and an interval between each of these grooves G1, G2, g1 and g2 is connected with subgrooves (m) and (n). In addition, a narrow notch S is installed in the shoulder block SH at the specified tilt angle alpha, for example, at 30 deg. to the equatorial surface with a pitch P in the circumferential direction. Then, a notch volumetric indes is set to an range of 2.5-15 while a circumferential rigid index of a pattern to 30-70, respectively. With this constitution, high-speed durability and abrasion resistance are all improved. |
