| 摘要 |
<p>A winter tyre comprises a tread band in which is formed a plurality of grooves, at least one block delimited by said plurality of grooves, at least one sipe formed in said block and extending between a top (7) and a bottom (8) of said sipe and being shaped so as to define in each of the block portions that are separated by said sipe: a first surface (11) which faces the other block portion and extends from said top (7) to an intermediate depth (P) of said sipe, which first surface (11) has a substantially straight profile, and a second surface (12) which faces the other block portion, is connected to said first surface (11), extends from said intermediate depth (P) to said bottom (8), and has an undulating profile formed by a series of concave portions (13) and convex portions (14), each having a respective crest (13a; 14a) the distance of which from a reference plane (A) comprising said first surface (11) increases progressively from said intermediate depth (P) to said bottom (8).</p> |
