摘要 |
A tyre tread comprises an elongate strip having a respective longitudinal groove (2) in each lateral portion of the strip constructed and arranged to partially close when the tread is subjected to tangential forces, e.g. during cornering, stiffening the tread in the contact area to reduce excessive movement of the tread in the contact area whilst maintaining the groove open at the tread surface. Partial closing is achieved by forming the groove as two tracts a first tract, which remains open during cornering, extending from the tread surface and a second tract, which closes during cornering, separated from the first tract by a sudden variation in groove width produced, for example, by a transverse step formed in one of the groove flanks or a protuberance projecting from the base of the groove. <IMAGE> |