Tyre tread for motor vehicles, particularly for snow-covered ground

Winter tire for vehicle wheels, provided with a tread comprising three circumferential grooves and a plurality of transverse grooves which jointly delimit four circumferential rows of blocks, namely two axially outer shoulder rows and two center rows at the sides of the equatorial plane. The transverse grooves converge on the equatorial plane in the direction of rolling specified for the tire. In the tread, each transverse groove of the center rows is made to comprise a widening of the cross section with an essentially circular profile, formed at a distance from the ends, for trapping snow. To obtain quieter running on dry roads, the front transverse edge profiles of the adjacent blocks of the center rows are made to comprise at least two successive curvilinear portions. These curvilinear portions are shaped in different ways and with opposite curvatures to each other, to form means of attenuating the noise arising from the impact of the tread pattern on dry roads when the tire is rolling.