A pneumatic tire includes a center land portion, intermediate land portions, and shoulder land portions, the land portions being partitioned and formed by four main grooves, and a plurality of lug grooves and sipes disposed in the land portions. The lug grooves disposed in the shoulder land portions do not communicate with the second main grooves. The groove area ratio is greater in the center region than in the shoulder regions. The distance (L1) from the tire equator to the center in the tire width direction of the first main groove is 15 to 25% of the distance (L) from the tire equator to the ground contact edge. The distance (L2) from the tire equator to the center in the tire width direction of the second main groove is 50 to 65% of the distance (L) from the tire equator to the ground contact edge.

A tire includes a tread having a crown main groove and shoulder main grooves extending in the tire circumferential direction. The crown groove has crown long side portions and crown short side portions inclined in the opposite directions and alternately formed in a zigzag shape extending in the tire circumferential direction, the shoulder main grooves have shoulder long side portions and shoulder short side portions inclined in the opposite directions and alternately formed in a zigzag shape extending in the tire circumferential direction, the crown main groove and shoulder main grooves are formed such that a crown long-short ratio La/Lb is larger than a shoulder long-short ratio Lc/Ld, where La is a length of each crown long side portion, Lb is a length of each crown short side portion, Lc is a length of each shoulder long side portion, and Ld is a length of each shoulder short side portion.

Exemplary embodiments described herein are directed to tire pitch sequence design methodologies that are usable to develop tire tread pitch sequences that will minimize objectionable tonal qualities and disperse the acoustic energy produced during tire rotation across a wider frequency band. The exemplary design methodologies employ iterative randomization of pitch subsequences, waveform generation and analysis of pitch subsequences and full pitch sequences, and associated sorting and ranking using an objective function with an applied penalty factor.

The present invention provides a tire for a vehicle comprising: a rotation axis, a midplane at a central position along the rotation axis; a circumferential tread portion around the rotation axis, the circumferential tread portion comprising: a tread pattern exhibiting at least a first pitch pattern and a second pitch pattern each comprising: a center block crossed by the midplane, and two side block alignments, said side block alignments being inclined with respect to one another and extending from the center block; the first pitch pattern including: a first pitch length, a first number of blocks; the second pitch pattern including: a second pitch length which is shorter than the first pitch length, and a third number of blocks which is greater than the first number of blocks.

The surface state of the treads of tires cured in a vulcanization mold manufactured by 3D printing represents an optimal compromise between cost, appearance, and grip performance of the tire. The texture is formed by an arrangement of contiguous elements of pyramidal shape, each element of pyramidal shape having a base of parallelogram type positioned on the tread surface, and an apex situated at a normal distance H from the base in the range 0.15 mm to 0.5 mm.

The invention relates to a pneumatic tire for a vehicle, having at least one surface element (2) that is formed on the outer surface of the tire and has a structure (6) which contrasts with a base level (N.sub.B) and gives the surface element (2) a roughness.

The contrast structure (6) is formed by a multiplicity of contrast structure cells (6a), which coincide in shape in plan view and are joined together in the form of a grid, wherein the contrast structure cells (6a) have irregular peak and trough structures (6b) of a surface-covering configuration, wherein the arrangement of the contrast structure cells (6a) and the configuration of the irregular peak and trough structures (6b) are such that, when considered in plan view, the irregular peak and trough structures (6b) can be transferred one into the other by congruence mapping.

A tire includes a tread portion including first and second tread edges, a first shoulder land portion including the first tread edge, and a first shoulder circumferential groove located inwardly in a tire axial direction of and adjacent to the first shoulder land portion and extending continuously in a tire circumferential direction. The first shoulder land portion is provided with a plurality of first shoulder lateral grooves extending from the first shoulder circumferential groove across the first tread edge, each of the plurality of first shoulder lateral grooves has a pair of first groove walls, and the pair of first groove walls is provided with a pair of first chamfer portions that extends from the first shoulder circumferential groove to a first location beyond the first tread edge.

A mold for molding a tire tread comprises a plurality of mold segments. Each of the plurality of mold segments includes an integer number of tread pitch repetitions. The plurality of mold segments are structured to be coupled to each other end-to-end so as to form the mold such that the mold includes an integer number of tread pitches. The mold also includes at least one mold end segment positioned on at least one end of the mold and has a mold end segment length shorter than a length of each of the plurality of mold segments.

A mold for molding a tire tread comprises a plurality of mold segments. Each of the plurality of mold segments includes an integer number of tread pitch repetitions. The plurality of mold segments are structured to be coupled to each other end-to-end so as to form the mold such that the mold includes an integer number of tread pitches. The mold also includes at least one mold end segment positioned on at least one end of the mold and has a mold end segment length shorter than a length of each of the plurality of mold segments.

A pneumatic tire comprises a plurality of main grooves extending in a tire circumferential direction, and a plurality of land portions that are partitioned by at least one contact patch end and the plurality of main grooves, the plurality of land portions comprise a center land portion that contains a center in a tire width direction, and a side land portion that is adjacent in the tire width direction to the center land portion, a dimension in the tire width direction of one land portion among the center land portion and the side land portion is less than a dimension in the tire width direction of the other land portion thereamong, and a maximum value of an amount by which the one land portion protrudes from a tread profile is greater than a maximum value of an amount by which the other land portion protrudes from the tread profile.