Provided is a pneumatic tire including center main grooves, shoulder main grooves, a center land portion, middle land portions, shoulder land portions, and lug grooves provided in each shoulder land portion. The pitch of the lug grooves is changed on the tire circumference. The profile line L1 that defines the road contact surface of the center land portion protrudes further to the outer side in the tire radial direction than the standard profile line L0. The profile line L2 that defines the road contact surface of the middle land portion and the shoulder land portion protrudes further to the outer side in the tire radial direction than the standard profile line L0. The ratio of the groove volume of the lug grooves to the size of the pitch of the lug grooves in the shoulder land portion decreases as the pitch increases, and increases as the pitch decreases.

In a tire, a plurality of outer resonators (25) are formed in an outer land portion (28) partitioned by two outer main grooves (21, 22) and arranged in a tire circumferential direction, a plurality of inner resonators (26) are formed in an inner land portion (29) partitioned by two inner main grooves (23, 24) and arranged in the tire circumferential direction, the outer resonator includes a first vertical groove (31) which extend in the tire circumferential direction, and a first branch groove (32) and a second branch groove (33) which have an inner volume smaller than that of the first vertical groove, extend in the tire width direction from both end portions of the first vertical groove in the tire circumferential direction such that the first branch groove and the second branch groove extend in directions opposite to each other, and are respectively opened to the two outer main grooves, and the inner resonator includes a second vertical groove (36) which extends in the tire circumferential direction, and a third branch groove (37) and a fourth branch groove (38) which have an inner volume smaller than that of the second vertical groove, extend in the tire width direction from the second vertical groove such that the third branch groove and the fourth branch groove extend in directions opposite to each other, and are respectively opened to the two inner main grooves.

A tyre for vehicle wheels includes a tread band on which grooves are formed, which generally define a tread pattern of the tyre. At least one pitch is defined in the tread pattern. The pitch extends axially on the tread band. The total number of pitches formed on the tread band is greater than 110.

A pneumatic tire includes circumferential main grooves extending in a tire circumferential direction and land portions partitioned and formed by the circumferential main grooves. The land portion of a center region and the land portions of left and right shoulder regions each have a plurality of sipes. Not less than 90% of the sipes disposed in the center region are constituted by two-dimensional sipes and not less than 90% of the sipes disposed in the shoulder regions are constituted by three-dimensional sipes. The left and right shoulder land portions each have a plurality of lug grooves arranged in the tire circumferential direction. A pitch number N_ce of the lug grooves in the land portion of the center region and a pitch number N_sh of the lug grooves in the land portions and of the left and right shoulder regions have a relationship such that N_ce>N_sh.

The present technology provides a pneumatic tire. In a tire meridian cross-sectional view, a profile line (PL1) of a center land portion (X) defined by two center main grooves (14a, 14b) protrudes outward in a tire radial direction further than a standard profile line (PL0). Profile lines (PL2, PL3) of sub-center land portions (Y1, Y2) and shoulder land portions (Z1, Z2) defined outward of the two center main grooves (14a, 14b) in the tire width direction protrude outward in the tire radial direction further than the standard profile line (PL0), the shoulder land portions (Z1, Z2) being defined further outward than the sub-center land portions (Y1, Y2). A pitch count (Po) of a vehicle mounting outer side region and a pitch count (Pi) of a vehicle mounting inner side region satisfy the relationship Po<Pi.

Method of determining the longitudinal pitch of blocks of a tread band having a raised pattern with a number of longitudinal grooves and transverse grooves; the method including the step of calculating a best longitudinal pitch of the blocks, to minimize pass-by noise at a given target speed, as a function of the resonance frequency of the longitudinal grooves and an integer greater than zero.

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 (1) having a tread (10) with from one to three tread pattern elements (MA, MB, LC) distributed over one revolution of a wheel. Each tread pattern element has first and second portions positioned on either side of an equatorial plane (C). Each portion of each tread pattern element has at least one main sipe (85) having the curvature of said portion, and substantially parallel to its edges, the main sipe (85) extends continuously from a first axial edge (24G, 24D) on a first side of the equatorial plane (C) to a connection point (90) situated in a main void (80) on a second side of the equatorial plane (C), the main void (85) extending to a second edge (24G, 24D) of the tread (10); the axial width of the main sipe (85) represents from 52% to 63% of the axial width of the tread (10).

A pneumatic tire reduces the columnar resonance noise of the tire while controlling the lowering of wet performances, wherein four circumferential grooves continuously extending in the circumferential direction of the tire are disposed in a treading face and a plurality of lateral grooves each having one end opened to the circumferential groove and terminated in a land portion are formed with respect to two circumferential grooves among the four circumferential grooves, and these lateral grooves and the respective circumferential grooves have such a groove width that both groove walls of the groove do not contact with each other in a ground contact face and one or more lateral groove are always completely included in the ground contact face, and an extending length of a portion of each lateral groove in the ground contact face having a groove width of the lateral groove corresponding to not less than 30% of a groove width of the circumferential groove is made not less than 40% of an extending length of the circumferential groove in the ground contact face.

A pneumatic tire is provided where, in a tread center portion, there are at least three pitch variations in terms of pitch length in the circumferential direction of the tire, and, taking n as the pitch count, the pitch lengths Pc Pc1, Pc2, Pc3, . . . , Pcn in order from longest to shortest satisfy the relationships Pc1/Pc2Pc2/Pc3, . . . , Pcn1/Pcn and Pc1/Pc2>Pcn1/Pcn.