| 摘要 |
PURPOSE:To improve running stability and avoid generation of cracks in the connection portion between a weir plate and a groove bottom by specifying projected length of the upper area of the weir plate and average thickness of the weir plate, in a low-noise tire in which the weir plate is arranged in a longitudinal groove, and constructing a lower area in such a way that it dents toward the groove wall side. CONSTITUTION:A weir plate 4 comprises an upper area 4a which is in form of a straight line and in which a projected length b at an optional point in the depth direction of a longitudinal groove 3 is 20-48% of the groove depth B at the position and a lower area 4b whose tip end is bent curvedly from the tip end of the upper area 4a to the groove wall 3a side. And an average thickness of the weir plate 4 is set to 20-80% of a projected length b0 of the weir plate on the tire surface. Further, height d of the upper area 4a is made as 30-80% of the depth D of the groove. Thereby, running stability can be improved without deteriorating low noise performance, and generation of cracks in the connection portion between the weir plate and a groove bottom can be prevented. |
