Tread (1) for a heavy-duty vehicle tire having, when new, a tread surface (10), with at least one evolving cut (2) comprising a part (22) hidden inside the tread which is delimited by opposing walls (221, 222) distant from one another by a maximum width Lc. The part (22) being extended towards the tread surface (10) by a sipe (21), opening into the hidden part (22) to be offset from one of the walls (221, 222) delimiting the hidden part to form a bridge situated radially over said hidden part (22). The tread having a plurality of grooves (4) open when new onto the tread surface (10), these grooves (4) opening into an evolving cut (2) to form a connecting region (41), the tread (1) further comprising, in at least 50% of the connecting regions (41, 42), a protuberance (5) extending over the entire height Hc of the hidden part (22) and over a maximum thickness Ep so as to act as a support for the bridge (211) situated radially over the hidden part (22) in the connecting region (41).

A tread (1) for a heavy-duty vehicle tyre, having a tread surface (10) and an undulating groove (2) formed therein, having, when new, external cavities (21) open onto the tread surface (10) and internal cavities (22) entirely situated there-beneath when new, these cavities (22) connected to cavities (21) by linking cavities (23), each external cavity (21) intersecting the tread surface (10) along a corner edge contour delimiting an opening (210) having two end regions (A1, A2) and a surface area Se measured on the tread surface (10). In each end region (A1, A2) at least one thin blade (41, 42) of rubbery material is formed which is secured to at least one of the walls delimiting the undulating groove to reduce the surface area of the opening (210) of each external cavity (21) viewed from the tread surface (10) when new.

Heavy goods vehicle tire, having a crown portion covered radially on the outside by a tread, this tread having at least two cut-outs, the central portion of the tread having a width Lc of between 35% and 70%, the crown portion comprising a reinforcement having at least two working layers having reinforcing elements, these reinforcing elements consisting of UHT-grade threads, having a mechanical breaking strength R satisfying the following relation: R≥(4180−2130×D), where D is the diameter of the thread expressed in millimetres, this tread being formed of at least two layers of superimposed material, the material forming the first layer with a breaking elongation of more than 600% at a temperature of 60° C., this tread being such that, in the central portion, the cavity ratio per unit volume is not more than 10% and the surface cavity ratio as new is not more than 10%.

Mould for moulding a tread of a tire, this tread having a thickness of material to be worn away and a tread surface intended to come into contact with the road surface when the tire is running, this mould having a moulding surface intended to mould the tread surface of the tread, and having a moulding element formed of a blade and a bar, the blade being attached to the moulding surface to mould a sipe in the tread, the bar, borne by the blade to form an enlarged part of maximum width D, being intended to mould a channel in the tread, this channel itself being intended to form a new groove when the tread becomes part worn. Each blade is delimited by two lateral faces forming between them a mean angle of between 6° degrees and 18°. The blade width decreasing from the mould surface when new, as far as the connection with the bar, the blade width meets the bar being at least equal to between 0.2 and 0.4 times the maximum width D.

Pneumatic tire comprising a tread (1) provided with two edges (2), a center (3) and a plurality of tread bars (10) distributed in a circumferential direction, each tread bar (10) extending in an oblique direction from one of the edges (2) towards the center (3) of said tread (1), the plurality of tread bars (10) comprising at least two adjacent tread bars (11, 12); each of said adjacent tread bars (11, 12) has at least one incision (20, 21, 23) extending along the length of the tread bar, each adjacent tread bar has an overall incision length (LGI) corresponding to the sum of the lengths of the incisions that are part of said tread bar, the widths (LB11, LB12) of said adjacent tread bars (11, 12) are different, and the overall incision length (LGI) in said adjacent tread bars (11, 12) is different.

A first tire includes a tread having a circumferential center rib and a circumferential intermediate rib laterally adjacent the center rib, the intermediate rib being separated from the center rib by a first circumferential groove, a second circumferential rib bordering the intermediate rib opposite the first circumferential groove, the tread further including two other circumferential grooves; at least one stiffener element disposed within each of the four circumferential grooves, the stiffener elements having a reduced height relative to a height of the center and intermediate ribs; and the stiffener element having a circumferentially oriented cut extending into an upper surface of the stiffener element toward a bottom of the stiffener element, the cut extending circumferentially through the stiffener element with the cut bounded by opposite laterally inward facing cut sides.

A tire with a resonator for noise reduction includes: a main groove unit which has a plurality of main grooves formed to extend along a circumferential direction of the tire; a resonance unit which is formed between a pair of the main grooves; a neck unit which is provided to communicate the resonance unit with one of the pair of main grooves; and a cuff unit which is provided to connect the resonance unit and the other of the pair of main grooves.

A tire including a tread portion, the tread portion having at least one main groove continuously extending in the tire circumferential direction, the tread portion including a rubber having a hardness at 60 C. of 58 or higher and a hardness at 0 C. of not more than 115% of the hardness at 60 C., the tread portion having a S.sub.50/S.sub.0 ratio of more than 1, wherein S.sub.0 denotes the sea proportion (%) in the tread ground contact surface of the new tire, and S.sub.50 denotes the sea proportion (%) when the tread portion is worn until the depth of the main groove reaches 50% of that of the new tire.

The tread has a total axial width W and a wearable thickness PMU of material and has at least four grooves on each side of a midplane that divides the tread axially into two parts. The grooves divide the tread into a middle, intermediate and edge regions 6. The middle region has an axial width Lm of at least 30% and at most 60% of the total width W. The total volume void ratio when new is less than 17%, and the middle region has a volume void ratio that is less than half the total volume void ratio. The middle region comprises a plurality of transverse sipes opening into the grooves, and the sipes have depths at least equal to 75% of the depth of the grooves. The number of transverse sipes in the middle region is greater than the number of transverse sipes on each intermediate or edge region.

The tread comprises circumferential grooves which delimit an intermediate row (I) and edge rows (B). The tread also has a plurality of V-shaped oblique grooves with branches that make an angle of 30 to 60 with the axial direction. The circumferential and oblique grooves delimit a plurality of V-shaped blocks in each intermediate row. In each V-shaped block, there is a canal below the tread surface, and this canal has a width of 2 to 6 mm and is intended to generate a new groove after a predetermined amount of wear. When new, each canal has openings that open into the oblique grooves. A bridge of material is formed between the V-shaped blocks and occupies heightwise at least 40% of the depth of the oblique grooves and doing so over a width at least 10 mm. The bridge of material is suitable for not closing the openings of the canals.