摘要 |
PURPOSE:To reduce noises during travelling by constituting longitudinal grooves circumferentially provided on a tire such that the relationship between each pitch length and height arranges specified main and auxiliary elements in different orders. CONSTITUTION:A longitudinal groove G1 constitutes a pattern constituting unit P consisting of a main element M1 of pitch length Rm1 and an auxiliary elements S1, S2 of pitch lengths Rs1, Rs2. And this pattern consisting unit P is constituted from pattern consistuting units P1, P2, P3 having the arranging sequence changed like M1-S1-S2, S1-M1-S2-S1-S2-M1. Also, pitch length Rm1 and height Hm1 of the main element M1 and pitch lengths Rs1, Rs2 and heights HR1, HR2 of auxiliary elements S1, S2 are set such that respective ratios Rs/Rm, HR/ Hm are respectively within the range of 0.2-0.7. Four longitudinal grooves G1 having thus the pattern consisting units P arranged in combination are arranged at equal intervals at both sides of the equator line C or tire. By this constitution can be reduced tire noise during travelling. |