Patent ID: 6408910
Filing Date: 2002-06-25
Classification: B29C,B29D,B60C,Y10S

Abstract:
A tread of thickness E for a tire, said tread having a running surface, limited transversely by lateral edges, said tread being provided when new with a tread pattern comprising at least a plurality of rubber blocks arranged circumferentially on at least one of its lateral edges, said rubber blocks being separated from each other by grooves oriented virtually transversely and separated from tread pattern motifs located axially to the inside by grooves oriented mainly circumferentially, wherein each of said plurality of blocks comprises:several successive layers defined radially beneath the running surface when new corresponding to levels of partial wear of the tread, each of said levels being defined by its distance measured relative to the ring surface when new, a first level being located at a distance of between 15% and 45% of the thickness E of said tread and the following levels being located at distances greater than said first level, and for each level of wear: at least one recessed channel of average width at least equal to the width of the transverse grooves, each recessed channel (1) having an average trace identical to the average trace of said transverse grooves, (2) forming a new groove opening radially towards the outside of the tread after wear of the new tread to the respective level, and (3) extending within the remaining thickness of the tread; and at least one recessed incision, not opening to the running surface of the tread when new and having, in radial projection on the running surface of the tread when new, a transverse orientation identical or virtually identical to that of the recessed channel(s) projected on the same surface and each incision having small width compared with the average width of said channel(s), each incision opening rally onto the running surface at the time of the opening of the recessed channel to form said new groove on said running surface and extending within the thickness of the tread over the entire depth of the opened channel(s).