Tire (1) for a heavy-duty vehicle of civil engineering type, and more particularly to the tread (2) thereof, and seeks to improve the grip thereof, while at the same time ensuring a satisfactory compromise with wearing and thermal endurance. The tread (2) comprises cuts (3, 4, 5) distributed, in a circumferential direction (XX) of the tire, among circumferential grooves (3) and, in an axial direction (YY) of the tire, transverse sipes (4) and transverse grooves (5), the cuts (3, 4, 5) delimiting elements in relief (6), each cut (3, 4, 5) being delimited by two faces facing one another and each face intersecting the tread surface (21) along an edge corner (311, 321; 411, 421; 511, 521). The tread (2) having a longitudinal edge corners ratio TA.sub.X equal to the ratio L.sub.X/S between the sum L.sub.X of the projections, on to the circumferential direction (XX), of the effective edge corner lengths, contained in an elementary tread surface portion of surface area S, and the surface area S, and a transverse edge corners ratio TA.sub.Y equal to the ratio L.sub.Y/S between the sum L.sub.Y of the projections, onto the axial direction (YY), of the effective edge corner lengths, contained in an elementary tread surface portion of surface area S, and the surface area S, the longitudinal edge corners ratio TA.sub.X is at least equal to 4 m.sup.?1 and the transverse edge corners ratio TA.sub.Y is at least equal to 6 m.sup.?1.

In a pneumatic tire 10 according to the present invention, as an average block edge component Dball is defined by an average of edge components of all blocks against a tire circumferential direction, an average sipe edge component Dsall is defined by an average of edge components of all sipes against the tire circumferential direction and an average block rigidity G is defined by an average of the rigidity of all blocks, a relation of 2.20 (mm).sup.3/N?(Dball/Dsall)/G?4.00 (mm).sup.3/N is fulfilled.

In a pneumatic tire 10 according to the present invention, as an average sipe interval h is defined by an average interval of sipes adjacent to each other in a tire circumferential direction and an average pitch length L is defined by an average length of a repeating unit of blocks in the tire circumferential direction, a relation of 0.130?(h/L)?0.400 is fulfilled.

In a pneumatic tire 10 according to the present invention, as an average block edge component Dball is defined by an average of edge components of all blocks against a tire circumferential direction and an average sipe edge component Dsall is defined by an average of edge components of all sipes against the tire circumferential direction, a relation of 0.15?(Dball/Dsall)?0.48 is fulfilled.

A tire includes a tread portion including first and second tread edges, three or more circumferential grooves, and four or more land portions. The circumferential grooves include a first shoulder circumferential groove nearest to the first tread edge. Each land portion is provided with only sipes and is not provided with lateral grooves. The land portions include a first shoulder land portion having the first tread edge, and a first middle land portion adjacent to the first shoulder land portion. The first middle land portion is provided with first middle sipes traversing the first middle land portion completely in the tire axial direction. The first shoulder land portion is provided with first shoulder sipes extending from the first shoulder circumferential groove to the first tread edge. The first shoulder sipes have a circumferential pitch length smaller than a circumferential pitch length of the first middle sipes.

A pneumatic vehicle tire in radial design that is a summer tire or all-season tire, with a profiled tread including rows of profile blocks and/or profile ribs running around the tire in circumferential direction, wherein the total number of sipes within each row of profile blocks and/or profile ribs is not more than 150, wherein the tread is in the form of a single layer or multiple layers with a radially outermost tread layer that extends at least over the width of the ground contact area, wherein the profile depth of the tread is up to 6.5 mm, and the tread or its radially outermost tread layer consists of a rubber material with a Shore A hardness at room temperature in accordance with DIN ISO 7619-1 of 40 ShA to 55 ShA.

A mould for manufacturing a tire includes a plurality of segments including a first segment. The first segment has a first end, an opposite second end, primary lamella blades that are arranged close to the first end, and secondary lamella blades that are arranged far from both the ends. An average of the heights of the primary lamella blades is at least 75% of an average of the heights of the secondary lamella blades. A bending strength of the primary lamella blades against bending in a circumferential direction of the mould is greater than a bending strength of the secondary lamella blades against bending in the circumferential direction of the mould. A tire is manufactured by the mould.

The invention provides for a heavy truck tire tread (1) having a longitudinal direction, a lateral direction and a thickness direction, said tread having a ground-engaging contact surface (CS) and comprising at least four main longitudinal grooves (3, 4, 5, 6) defining at least five main longitudinal ribs (9, 10, 11, 12, 13), the at least four main longitudinal grooves comprising at least one and not more than three open grooves (3, 6) and at least two partially hidden grooves (4, 5), each of said at least two partially hidden grooves comprising openings (41, 51) to the ground-engaging contact surface (CS) and an undersurface channel (42, 52) that is connected to the openings by ducts (43, 53) extending substantially in the thickness direction, longitudinal sipes (44, 54) extending substantially along the longitudinal direction connecting successive openings to the channel, said tread comprising at least two non-shoulder main ribs (10, 11, 12), said at least two non-shoulder main ribs comprising lateral sipes (105, 115, 125) extending in the lateral direction, the tread comprising at least 120 of said lateral sipes, wherein for each partially hidden groove: a total surface area of all openings is less than 200 cm2; an average height of said channel is greater than 5 mm; and an average section area of said channel is greater than 15 mm2.

A heavy duty pneumatic tire includes a tread surface having, on at least a section thereof, a plurality of circumferential-direction grooves extending along a tread circumferential line and land portions defined either by the circumferential-direction grooves or by the circumferential-direction grooves and tread ground contact edges. The land portions include at least one partitioned land portion in which a plurality of narrow width-direction grooves extending in a tread width direction are provided. A prescribed internal pressure is at least 750 kPa. A depth of the circumferential-direction grooves, represented by H, satisfies a relationship 7 mmH13 mm. A tread circumferential-direction spacing of the narrow width-direction grooves, represented by W, satisfies a relationship 5 mmW20 mm.

Tire tread having a central part (I) made from at least one first rubber compound and having at least one circumferential rib (121-123) formed of a plurality of blocks (1210) separated by sipes; a first and a second lateral part (II and III) made of at least a second and third rubber compound, and having a circumferential rib (131,141) formed by a plurality of blocks (1310,1410), separated by sipes, wherein the at least one second and third rubber compounds have a value of tan at 23 C.at a frequency of 10 Hz and an elongation of 10% of less than 0.25, wherein the complex modulus G*(T) of the at least one first rubber compound is greater than the complex moduli G*(T) of at least one second and third rubber compounds for all temperatures T greater than or equal to 0 and less than or equal to 60 C.