Medium/heavy duty motor-vehicle tyres provided with a tread of the universal type

摘要

In a tyre tread band for medium/heavy duty motor-vehicles a tread band is provided with circumferential grooves (2a, 2b, 2c) confining three pairs of respectively centre (5c), intermediate (5b) and shoulder ribs (5a). Respective blocks (7b, 7a) are defined along the centre and intermediate ribs and they are confined by transverse cuts (8b, 8a). The centre cuts (8b) impart a cusp-shaped end conformation (9) and a hollow-shaped end conformation (10) to the respective blocks (7b), and the shapes of said end portions mutually match. The intermediate cuts (8a) run in the linear extension of the centre cuts (8b) to give the respective blocks a rhomboidal configuration. The tyre can be alternately associated with a driving axle or a driven axle, by merely reversing its direction of rotation, so that the following results are selectively achieved: an increase in the traction capability by the intermediate blocks or an increase in the directional capability as a result of the mutual wedging between the centre blocks at the ground-contacting area.