| 摘要 |
PURPOSE: A pneumatic tire is provided to reduce cracks created around the bottom of a groove by setting a groove borderline of a vertical main groove. CONSTITUTION: A pneumatic tire comprises a vertical main groove. A borderline of the vertical main groove comprises an inner wall part(13), an inner circular arc part(14), an outer wall part, and an outer circular arc part(15). The inner wall part is extended from an side edge(9i) of a tire equator to the inner side of a tire radius direction. The inner circular arc part is extended to the inner wall. A curvature radius of the inner circular arc part is smaller than a curvature radius of the inner wall part. The outer wall part is extended from the outer side edge of the width main groove's thread part toward the inner side of the tire radius as a length smaller than an inner wall part's. The outer circular arc part is extended to the outer wall and has a smaller curvature radius of the outer wall part. |
