A pneumatic tire includes circumferential main grooves extending in the tire circumferential direction on the tread surface, and in widthwise outermost land portions, widthwise grooves extending from the tread edges inward in the tire width direction and widthwise sipes extending from the tire widthwise inner edge of the widthwise grooves inward in the tire width direction and connecting to the circumferential main groove. Each widthwise sipe includes a widened portion, by the sipe bottom, with a larger sipe width than at the tread surface. A rectangle ratio is less than 0.8. In a tire radial region containing the widened portion, the widened portion includes a portion extending at a first angle relative to the tire width direction. In plan view of the tread surface, each widthwise sipe extends along the tire width direction or at a second angle smaller than the first angle relative to the tire width direction.

A winter tire tread band having: a number of longitudinal and transverse grooves defining a number of blocks, each projecting radially upwards from a base surface of the tread band; and a number of sipes formed in at least some of the blocks, and each of which extends radially inwards of a corresponding block, from a top surface forming the rolling surface of the tread band; each sipe has a wave pattern when the corresponding block is viewed in any one of three planes perpendicular to one another and defined by a longitudinal axis, a transverse axis, and a radial axis.

In the pneumatic tire according to this disclosure, a plurality of sipes on a tread surface include a large intermediate width sipe 4 having: a pair of intermediate sipe wall surface portions 61, a pair of bottom-side sipe wall surface portions 62 and a pair of tread-surface-side sipe wall surface portions 63; and within a central region of the tread surface, a spacing along a tire circumferential direction between the large intermediate width sipe and another sipe or groove is 2.0 to 4.0 times of a sipe depth D of the large intermediate width sipe.

A tread kerf of a snow tire is capable of securing the performance of the tire on a dry road, a wet road, a snowy road, and an icy road, maintaining uniform rigidity of the block, and improving wear resistance. The tread kerf is formed in the outer surface of a tread block of the snow tire in a depth direction of the block in a shape of a polygonal wave extending along the outer surface of the block, wherein the entrance distance of the polygonal wave is less than the bottom distance of the polygonal wave such that side surfaces between the entrance and the bottom of the polygonal wave are formed as inclined surfaces, the distance between which decreases toward the entrance. The polygonal wave is moved in an advancing direction of the polygonal wave while being twisted in the depth direction of the block.

A tire 1 comprises a tread portion 2 provided with an outboard shoulder land region 8 with outboard shoulder sipes 26. The outboard shoulder sipe 26 comprises a deep bottom part 27 and a shallow bottom part 28. The shallow bottom part 28 comprises an axially outer part 30 extending axially inwardly from the axially inner end 27i of the deep bottom part 27, an axially inner part 31 extending axially outwardly from the outboard shoulder main groove 4, and a middle part 32 connecting therebetween. The axially outer part 30, axially inner part 31 and middle part 32 have different angles with respect to the tire axial direction.

The pneumatic tire comprises a tread portion 2 provided with first sipes 25 and second sipes 26 and having a first tread half portion 21 and a second tread half portion 22. The first sipes 25 are smoothly continued from a crown land region 10 in the second tread half portion 22 to a shoulder land region 13 in the first tread half portion 21 through a crown main groove 3 and a shoulder main groove 5. The second sipes 26 extend from the crown land region 10 in the second tread half portion 22 toward a second tread edge Te2.

A tire includes: a tread band on which is defined a radially outer tread surface, a first plurality of blocks provided on the tread band, and at least a first sipe of the restrained type extending on at least one block of the first plurality in a substantially axial direction defined on the tread band. The first sipe is configured so as to define, between a first and a second block portion divided by the first sipe, at least two separate and distinct couplings of the male/female type, such as to prevent the mutual displacement of the block portions in any direction which, at the block, is substantially tangential to the tread surface, and such as to permit mutual displacement of the block portions in a direction incident to the tread surface. In addition, the first sipe does not intersect any other sipe of the restrained type within the block.

A pneumatic tire, having in a tread surface thereof a pair of circumferential grooves formed on respective sides of the tire equatorial plane in the middle, a rib-like central land portion row demarcated by the circumferential grooves, and a plurality of lateral grooves extending between the central land portion row and each tread end, comprises in each half region of the tread: a row of first intermediate blocks each having a circumferential length D2 and demarcated by the lateral grooves, the corresponding circumferential groove, and first longitudinal grooves; and a row of second intermediate blocks demarcated by the lateral grooves, the first longitudinal grooves, and second longitudinal grooves, wherein facing openings of the first/second longitudinal grooves adjacent in the tire circumferential direction are offset from each other, and provided that D1 represents a circumferential distance between adjacent ends of the adjacent first and second intermediate blocks, D1D2/2.

A pneumatic tire having lug grooves in shoulder land portions that each include one end reaching at least a ground contact edge and an other end terminating in the shoulder land portion. Sipes in the shoulder land portions each include one end communicating with a shoulder main groove and an other end terminating in a ground contact region. Lug grooves in intermediate land portions each include one end communicating with the shoulder main groove and an other end terminating in the intermediate land portion. Sipes in the intermediate land portion each include one end communicating with a center main groove and an other end terminating in the intermediate land portion. Sipes in the center land portion each include one end communicating with the center main groove and an other end terminating in the center land portion without exceeding a tire center line.

The tire 10 of this disclosure is characterized in that at least one of the land portions comprises at least one sipe unit 60, both ends of each of one sipe 6a and the other sipe 6b constituting a pair of sipes terminates in the land portion, the one sipe 6a and the other sipe 6b are arranged opposing each other in the tire circumferential direction and have long sides extending in the tire width direction, respectively, the one sipe 6a has a short side 62a extending from either end e1 of the long side 61a in the tire width direction to approach the other sipe 6b side, and the other sipe 6b has a short side 62b extending from the other end e2 of the long side 61b in the tire width direction to approach the one sipe 6a side.