Patent ID: 6874552

Claim:
A tread of total thickness comprising grooves of a groove depth at most equal to the thickness defining motifs in relief which are provided with at least two lateral faces, at least one of these motifs being provided with at least one first incision and at least one second incision, said incisions each being defined by two main lateral surfaces connected by an end surface, each first incision opening on to two lateral faces and on to a running surface of the tread when new, each second incision extending at least as far as the groove depth wherein: each first incision, of a maximum depth, has a continuous trace over any surface parallel to the running surface when new between said running surface when new and a minimum depth at most equal to 80% of the maximum depth of said first incision, said depths being measured perpendicular to the running surface when new, this trace being of a length at least equal to 75% of a length of the trace of the same first incision on the running surface when new, and the end surface forming the bottom of each first incision extends between the minimum depth and the maximum depth, the total length of the trace of this first incision over any surface parallel to the running surface when new and located at a distance of between the minimum depth and the maximum depth decreasing gradually to be equal to a length at the maximum depth, this length at the maximum depth being at most equal to 75% of a length of the trace of this incision at the minimum depth, and, each second incision has an end surface which forms the apex of said second incision—corresponding to the surface of the incision connecting the main walls of said incision and located closest to the running surface when new—extending between a minimum depth of said second incision and a maximum depth of said second incision, the minimum depth of said second incision being less than the maximum depth of said second incision, these depths being measured relative to the running surface when new, and in that with each first incision there is functionally associated at least one second incision such that for the motif in relief in question and in the zone of contact of the tire with the ground, and whatever the level of wear of the tread, the total of the lengths of the traces of the first and second incisions on the running surface is greater than 75% of the total length of the traces of all of the first incisions in contact when the tread is new; wherein the associated first and second incisions are offset from one another in a direction transversely of the main lateral surfaces by a distance greater than zero and sufficient to prevent joining of the associated first and second incisions during tread wear.