| 摘要 |
PURPOSE:To provide a pneumatic tire capable of making coasting traveling noise reduction and noise reduction in acceleration and deceleration compatible with each other. CONSTITUTION:Ribs 16A, 16B, 16C, 16D, 16E are formed by providing circumferential grooves 14 on a tread 12. The ribs 16B and 16D positioned inside the ribs 16A, 16E are made lower by one step, moreover, the rib 16C is made lower by one step. Since frictional force on the tire equatorial surface CL side of the tread 12 to be hardly vibrated in acceleration and deceleration is decreased less than that on the shoulder part 22 side, distortion of rubber of the tread 12 on the tire equatorial surface CL side in acceleration and deceleration is decreased, as this result, frictional sound, namely, noise in acceleration and deceleration is decreased. Moreover, since noise in acceleration and deceleration can be decrease without increasing stiffness of the ribs, coasting traveling noise is not increased. |
