Patent ID: 9616715
Date: 2017-04-11
CPC Classifications: B60C

Claim:
1. A tread for a tire adapted to be fitted to the driven axle of a heavy goods vehicle, this tread comprising: a plurality of circumferential grooves each having a depth and a width, at least three ribs delimited by the circumferential grooves, each having two lateral faces, a height measured in the radial direction and a width measured in the axial direction, two edge rows axially delimiting the tread, wherein each rib is provided with a plurality of sipes able to close at least in part as they enter a contact patch in which the tire is in contact with a road surface, herein these sipes open onto each lateral face of the rib to form two edge corners and have a depth at least equal to 50% of the height of the rib, wherein these sipes in pairs delimiting an elementary rib volume and an elementary contact surface, wherein, on each elementary volume delimited by two sipes of one and the same rib there is formed a void volume opening on the contact face in the new state, wherein this void volume has a total area on the tread surface at least equal to 0.4% and at most equal to 1.5% of the area of the elementary contact surface, wherein this void volume has a depth at least equal to half the depth of the grooves, wherein this void volume is determined such that it remains open as it passes through the contact patch so as to allow any liquid present on the road surface to be picked up, wherein this void volume is located in to a central part of the elementary volume, wherein this central part corresponds to a radial cylinder formed in the elementary volume and tangential to the sipes delimiting this elementary volume.