Abstract: The present invention provides a pneumatic tire capable of ensuring good braking performance by making an edge effect be fully demonstrated by suppressing upward deformation of edge portions of a block. A block row constituted of plural shoulder blocks 24 is provided on the outer side in the tire widthwise direction of the center rib 16, with a circumferential fine groove 18 disposed therebetween. A block row constituted of plural shoulder blocks 32 is provided on the outer side in the tire widthwise direction of the center rib 26, with a circumferential shallow groove 28 disposed therebetween.

Abstract: A pneumatic tire according to the present invention includes blocks on its tread which are segmented by plural circumferential grooves 3 extending along a tire circumferential direction and plural lateral grooves 5 extending along a tread width direction. Circumferential sipes extending along the tire circumferential direction are provided in the blocks. Inside circumferential sipes extend straight along a tire radial direction and outside circumferential sipes extend along the tire radial direction in zigzag patterns. According to the present invention, a handling performance, especially, a cornering performance can be improved regardless of road surface conditions.

Abstract: The present invention provides a pneumatic tire having: a circumferential groove continuously extending in the tire circumferential direction in a ground contact surface of a tread portion; and a resonator provided in a land portion and constituted of a resonance cell portion opened to a ground contact region at a position distanced from the circumferential groove and a siping portion making the resonance cell portion communicate with the circumferential groove, wherein change in a tread pattern as time lapses can be alleviated without scarifying an effect of reducing pipe resonance sounds. Specifically, an opening width of the siping portion at the ground contact surface of the tread portion is designed to change in the longitudinal direction thereof such that the opening with is relatively narrow on the side of the circumferential groove and relatively wide on the side of the resonance cell portion.

Abstract: At least one of land portion rows 14, 15, 16 that are formed in a tread surface portion 10a is constituted by a first land portion 17 and a second land portion 18 being alternately and consecutively arranged along the tire circumference direction R, and a first top surface portion 17a and a first inclined surface portion 17b whose recess amount inward in a radial direction of the tire gradually increases in accordance with heading from the first top surface portion 17a toward the outer side in a width direction of the tire H are provided in a first land portion 17, and a second top surface portion 18a and a second inclined surface portion 18b whose recess amount inward in the radial direction of the tire gradually increases in accordance with heading from the second top surface portion 18a toward the inner side in the width direction of the tire H are provided in a second land portion 18, and by the first inclined surface portion 17b and the second inclined surface portion 18b mutually overlapping in the circ

Abstract: A pneumatic radial tire in which a plurality of land portion rows 2 are formed by a plurality of main grooves that extend in the circumferential direction on a tread portion of a tire, and a thin groove 3 that extends in the tire circumferential direction is formed in at least one shoulder land portion row 2A that is positioned on the tread end among the plurality of land portion rows. A land portion 5 that is positioned between, the thin groove 3 and the tread end 4 is partitioned into a plurality of blocks 5a by a lug groove 6 that extends in the tire width direction and whose maximum groove depth is set deeper than the groove depth of the thin groove, and the groove depth of the lug groove continuously changes so as to become a maximum at an intermediate position between the thin groove and the tread end. According to the present invention, it is possible to provide a pneumatic radial tire that can achieve improved drainage performance.

Abstract: It is an object to improve uneven wear resistance in a tread portion in a pneumatic tire having conductive rubber arranged in a part of the tread portion. Foamed rubber is provided in the tread portion 12 and a foamed rubber conductive layer 14 employing the foamed rubber is arranged in a part of the tread portion 12. Furthermore, uneven wear due to a difference of wear resistance between the foamed rubber conductive layer 14 and other tread rubber 22 can be suppressed by setting a foaming rate of the foamed rubber conductive layer 14 higher relative to other tread rubber portion 22.

Abstract: A plurality of shallow grooves which are shallower than a sipe are formed on land sections formed on treads of a pneumatic tire. The shallow grooves are configured so that a total sectional area of the shallow grooves per unit area in a cross section in a tire width direction in at least one of tread end areas arranged at end sides of the tread surface in the tire width direction or land end areas arranged at portions adjacent to a drain main groove on the land sections becomes larger than a total sectional area of the shallow grooves per unit on the other areas.

Abstract: A pneumatic radial tire comprises a tread provided with many blocks defined by grooves and/or sipes, in which (1) a peripheral portion of each of the blocks is chamfered in form of a curve or a straight line over a given region at a given chamfering depth in a mold during the vulcanization of the tire, and (2) the outer surface of the block becomes flat or substantially flat when the tire after the vulcanization is assembled onto a normal rim and inflated under a normal internal pressure.