| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a pneumatic tire in which siping shapes arranged at tread surface blocks are improved, a driving/braking performance and an operating performance at an icy and snowy road surface, a driving/braking performance and an operating performance at a dry road surface and a wet road surface are kept at their higher levels. <P>SOLUTION: There is provided a pneumatic tire in which blocks 5, 6 are defined at a tread surface 1 and one or more sipings 7 extending in a tread width direction or extending while being inclined in respect to the tread width direction are arranged. At least three portions, i.e. a surface portion 8, intermediate portion 9 and siping bottom portion 10 are arranged in sequence at each of the sipings 7 in its depth direction. The surface portion 8 is formed to extend in a zig-zag shape in an extending direction of the siping at an amplitude P and a pitch Q and reduce the amplitude P toward the intermediate portion 9 and at the same time the intermediate portion 9 is formed at the siping wall surface in a flat shape, and the siping bottom portion 10 is formed in a shape extending in a zig-zag form in at least a depth direction. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
