| 摘要 |
PURPOSE:To enhance side-slip resistance on icy road surfaces and driving stability on dry road surfaces by providing virtual sections on a tread along the circumferential direction of the tire, specifying lateral grooves in each sections, and providing a predetermined longitudinal siping in a center portion between predetermined points. CONSTITUTION:A tread 2 is virtually divided at a reference line L into reference-line section (S) at equal internals in its circumferential direction, and one of the reference- line section (SA) is provided with an inclined lateral groove 5MA passing a circumferential middle point M and having the greatest angle of inclination to the reference line L on the equator C of the tire. Further, a lateral groove 5 inclined in the same direction as the groove 5MN and at an angle that increases toward the middle point M, an inclined groove 5ME inclined at the same angle as the inclined groove 5MA in another reference-line area ME and at the greatest angle in the opposite direction, and a similar lateral groove 5 are provided, with the inclined grooves 5MA, 5ME joined to respective longitudinal groove portions 6A, 6E at axial end points F1, F2. A longitudinal siping 9, which is 1.0 to 2.0mm in width and 0.6 to 0.8 times as deep as a main groove 3, is provided in a center portion D between quarter points of tread width. Therefore driving stability on dry road surfaces can be enhanced while snow performance is maintained. |
