Abstract: Provided is a pneumatic tire for motorcycle in which the abrasion resistance and the steering stability of the tire at the time when the motorcycle is travelling while leaning sideways are combined by resolving the above-mentioned problems and improving the tread pattern. Provided is a pneumatic tire for motorcycle including a tread portion 11, a pair of sidewall portions 12connected to both sides of the tread portion and a pair of bead portions 13individually connected to the sidewall portions. The tire tread portion has a tread pattern having a plurality of transverse grooves 1to 9.

Abstract: Tire tread comprising a tread surface intended to come into contact with a roadway, this tread comprising at least one sipe extending in a main direction D and of mean width E, this sipe comprising in the main direction D at least one part sipe of shallow depth HF and at least one part sipe of great depth HG, the depth HF being less than the depth HG, each part sipe of shallow depth and each part sipe of great depth comprising an end region, this tread further comprising at least one insert oriented in a direction different from the main direction D of the sipe, this insert being positioned wholly within the thickness of the tread so as to be situated radially on the inside of a part sipe of shallow depth HF, this tread being such that at least the part sipe of shallow depth HF situated radially on the outside of the insert is provided, at its end region, with a widening forming a channel of maximum width W, this maximum width W being greater than the mean width E of the sipe.

Abstract: A heavy duty tire comprises a tread portion provided with a central circumferential groove, a crown circumferential groove on each side thereof and crown axial grooves extending therebetween so as to for crown blocks. The crown block is circumferentially subdivides into two block pieces by a crown narrow groove. The crown axial groove is provided in the groove bottom with a tie bar rising therefrom and connecting the circumferentially adjacent two crown blocks each other. The crown axial grooves are inclined at an angle ? of from 10 to 30 degrees with respect to the tire axial direction. The central circumferential groove and an axially inner part of the crown axial groove which part is axially inside the tie bar, are shallower than the crown circumferential groove.

Abstract: A pneumatic tire is provided in a tread portion with a center land portion which is defined between center main grooves and whose top surface has a certain area and a maximum axial width of 15% to 19% of a tread width. The center land portion is provided with axial sipes and recesses. The recess extends from the center main groove toward the tire equator, and has a depth of 60% to 80% of the depth of the center main groove. The total area of the recesses is 5% to 9% of the area of the above-mentioned top surface. The center land portion is formed as a substantially continuous rib.

Abstract: A pneumatic vehicle tire for commercial vehicles is provided wherein the wet traction properties are improved with simultaneously good rolling resistance properties. At least 120 transverse grooves are arranged in each of the central profile ribs over the entire circumference of the tire. The width (B1) of the transverse grooves in the central profile ribs is maximally 1.5 mm at a distance of 3.5 mm from the profile surface, and the width of each inner circumferential groove is maximally 4 mm at a distance of 3.5 mm from the profile surface.

Abstract: A motorcycle tire has a unidirectional tread pattern formed by a circumferentially extending center main groove, and main oblique grooves each with a branch groove. The main oblique groove has an axially inner end inside a zero-camber ground contacting width and an axially outer end outside the zero-camber ground contacting width. The axially outer end is positioned in a range between 0% and 20% of the developed half tread width from the tread edge. The branch groove is composed of a first inclined part extending from the main oblique groove at an angle ? with respect to the tire circumferential direction, and a second inclined part extending at an angle ? less than the angle ?. When the developed half tread width is axially equally divided into five portions, the land ratio of each of the five portions is 75% to 85%.

Abstract: A pneumatic tire comprises a tread portion provided on each side of the tire equator with a land zone defined between two circumferential main grooves, wherein the land zone is provided with axial grooves extending between the main grooves and inclining to a first circumferential direction at an angle of from 30 to 50 degrees with respect to the tire axial direction, and auxiliary grooves inclining to a second circumferential direction opposite to the first circumferential direction. The axial groove is shallow in its axially-inner-main-groove side in comparison with its axially-outer-main-groove side. The auxiliary groove is deep in its axially-inner-main-groove side in comparison with its axially-outer-main-groove side.

Abstract: A pneumatic tire having improved braking performance includes sides and a tread section between the sides. In each of two regions on opposite sides of a tire centerline in the tread section, two circumferential main grooves extend along a tire circumferential direction in a zigzag shape, first lug grooves extend from an inner circumferential main groove to a pattern end, and second lug grooves extend toward the pattern end from the outer circumferential main groove. A wall of the inside circumferential main groove includes wall surfaces with a wall angle varying along the circumferential direction. An outside land section between the main grooves includes a notched lug groove extending in a tire widthwise direction from either the inside or outside main groove and closes within the outside land section. A groove depth of the notched lug groove is shallower than that of the first and second lug grooves.

Abstract: A pneumatic tire for heavy load has a tread, circumferential grooves (2) extending continuously in the tread circumferential direction, transverse grooves (5) opening to the circumferential grooves (2) adjacent each other in the tread width direction, and a block (6) defined by the circumferential grooves (2) and the transverse grooves (5) on a surface (1) of the tread. The block (6) is provided with one or more shallow grooves (7-9) having an average groove depth shallower than a groove depth of the circumferential grooves (2) adjacent to the block (6). The average groove depth of the shallow grooves (7-9) is greater than 20% and less than 80% of the groove depth of the circumferential grooves (2). At least one of the shallow grooves (7-9) opens to at least one of the transverse grooves (5) and the circumferential grooves (2) adjacent to the block (6).

Abstract: A tire tread having a layered design is provided. In a first layer of the tread, sipes extend transversely to provide traction in the first stage of the wear life of the tread. In a second layer of the tread, the width of the sipes along the circumferential direction is increased to provide for improved traction in a second stage of the wear life. The increased width is provided by a void that opens to a circumferential groove only along one end. Because the void opens only along one end, a decrease in acoustical effects such as drive by noise can be provided.

Abstract: A tire tread is provided having a layered design that includes bridged and unbridged circumferential grooves during earlier stages of tread life while transverse and unbridged circumferential grooves are provided at later stages of tread life. Together, the combination of grooves can provide desired wet adherence performance without unacceptable compromises of tread wear and/or rolling resistance. Pockets can also be provided at the end of the transverse grooves to increase the volume available for receipt of water during wet traction.

Abstract: A pneumatic tire is provided which includes a plurality of drainage grooves positioned on each side of a tire equator line that extend at an angle in a direction opposite a rotating direction while curving outward in a tire width direction in a tread portion, with an end of a leading edge closed and an end of a trailing edge open to a tire side. A plurality of sub grooves extending from the drainage grooves in the rotating direction is provided, where an end of the leading edge is closed. The drainage grooves and the sub grooves are arranged so that spacings W1, W2, and W3 gradually increase outward in the tire width direction, groove area ratios RA to RE satisfy the relationships |RB?RA|?9%, RA>RC>RD, and RB>RE, and a groove depth of the drainage grooves in the center region is greater than that in the shoulder portion.

Abstract: A pneumatic tire comprises a tread portion with a land ratio of from 75% to 80%, the tread portion provided with crown main grooves having groove widths of 2.0-8.0 mm and groove depths of 15.0-20.0 mm, shoulder main grooves having groove widths of from 8.0-14.0 mm and groove depths of from 15.0-20.0 mm and lateral narrow grooves with groove widths of 0.6-2.0 mm and groove depths of 15.0-20.0 mm, wherein each main groove has a cross section including a groove bottom and groove walls, each groove wall includes an inner part and an outer part, the inner part has an inclination of not more than 1 degree with respect to a groove centerline, and the outer part has an inclination larger than that of the inner part.

Abstract: Provided is a pneumatic tire which is capable of securing a driving stability on dry road surfaces and concurrently of improving snow performance without worsening its pattern noise. The pneumatic tire includes four main grooves each extending in its tread part in a tire circumferential direction, and the four main grooves partition the tread part into: a center land part; paired intermediate land parts located with the center land part being interposed in between; and paired shoulder land parts located with the center land part and the paired intermediate land parts being interposed in between. Each of the intermediate land parts and the shoulder land parts includes multiple V-shaped grooves each configured of: a thick groove part extending in a tire width direction; and a thin groove part extending in the tire circumferential direction.

Abstract: A pneumatic tire (1) provided in the tread portion (2) with a row (5R) of crown blocks (5b) divided by crown axial grooves (8), two rows (6R) of middle blocks (6b) divided by middle axial grooves (9), and two rows (7R) of shoulder blocks (7b) divided by shoulder axial grooves (10), Each of the crown axial grooves (8) is circumferentially aligned with one of the middle axial grooves (9) such that the crown axial groove (8) is positioned within a middle-axial-groove range (Mc) defined between 1st and 2nd axial straight lines (Za and Zb) which are drawn passing through 1st and 2nd extreme circumferential end points (9a and 9b) of the middle axial groove (9), respectively. The circumferential length of the middle-axial-groove range (Mc) is not less than 25% but not more than 50% of a pitch length (P) defined between the two 1st extreme circumferential end points (9a and 9a). The middle-axial-groove range (Mc) does not overlap with any of the shoulder axial grooves (10).

Abstract: A heavy duty pneumatic tire comprises a tread portion provided with a crown main groove and a middle axial groove. The middle axial groove extends axially outwardly from its axially inner end axially outwardly spaced apart from the crown main groove and inclines with respect to the tire circumferential direction at an angle of from 45 to 75 degrees. In a cross section along the widthwise center line of the middle axial groove, an end wall of the axially inner end is inclined at an angle 0 to 50 degrees with respect to the normal direction to the tread from the radially outer edge of the end wall toward the groove bottom, and a corner between the end wall and the groove bottom is chamfered by an arc having a radius of curvature of 1 to 10 mm.

Abstract: A pneumatic tire having improved braking performance includes sides and a tread section between the sides. In each of two regions on opposite sides of a tire centerline in the tread section, two circumferential main grooves extend along a tire circumferential direction in a zigzag shape, first lug grooves extend from an inner circumferential main groove to a pattern end, and second lug grooves extend toward the pattern end from the outer circumferential main groove. A wall of the inside circumferential main groove includes wall surfaces with a wall angle varying along the circumferential direction. An outside land section between the main grooves includes a notched lug groove extending in a tire widthwise direction from either the inside or outside main groove and closes within the outside land section. A groove depth of the notched lug groove is shallower than that of the first and second lug grooves.

Abstract: A pneumatic tire 1 which includes a plurality of rib-shaped land portions extending in a tire-circumferential-direction and in which a circumferential groove is formed extending in the tire-circumferential-direction between the land portions. The circumferential groove is provided with an intra-groove groove formed to recess inwardly in a tire-radial-direction from the circumferential groove while having its upper ends at a groove bottom of the circumferential groove. Paired inner wall surface and outer wall surface forming the intra-groove groove each continuously extend in tire-circumferential-direction while meandering in tread-width-direction. The intra-groove groove includes a wide groove portion in which a groove width of the intra-groove groove in tread-width-direction is a predetermined width; and a narrow groove portion which is continuous with the wide groove portion and which has a narrower width than the predetermined width.

Abstract: A pneumatic tire 1 according to the present invention comprises at least land portion formed by circumferential groove 3,5 extending in circumferential-direction. The land portion includes land portion 11 having groove side wall 17 forming the circumferential groove 3 and land portion 15 having groove side wall 19A forming the circumferential groove 3. The groove side wall 17 and the groove side wall 19A meander in the circumferential-direction in surface view. A groove width of the circumferential groove 3 in width-direction changes in predetermined cycles in the circumferential-direction. The land portion 15 includes wide land portion in which width of the land portion in the width-direction is predetermined width, and narrow land portion in which the width in the width-direction is narrower than the predetermined width. A surface of the wide land portion is provided with recess portion 23 recessed inward in radial-direction from surface of the land portion 15.

Abstract: A pneumatic tire includes two circumferential main grooves within a ground-contact width of a tread, and a group of polygonal blocks between the two circumferential main grooves. The group of polygonal blocks includes a plurality of polygonal blocks arranged in at least two longitudinal rows in a tire circumferential direction and a plurality of transverse rows in a tire width direction. Each polygonal block has not less than five sides, and is defined by narrow grooves. The polygonal blocks in the adjacent longitudinal rows are arranged so as to be staggered from each other in the tire circumferential direction. The group of polygonal blocks has a widthwise center that is positioned within a 50% width region of the ground-contact width of the tread across a tire equatorial plane.

Abstract: A radial tire for a handling vehicle, comprising a tread in which the thickness in the radial direction in the circumferential mid-plane is greater than 40 mm. The tire comprises at least three circumferential grooves, at least the central circumferential groove having an axial width L of less than 15 mm and a radial depth H which are such that the ratio of axial width L to radial depth H is between 0.1 and 0.3.

Abstract: Tyre intended to be fitted to a vehicle carrying heavy loads comprising a tread band (10) provided with a plurality of grooves (2) of transverse overall orientation, this tread band being characterized in that it is formed of at least three rubber materials: a first material M1, in the median part of the tread band, having a secant modulus at 10% elongation measured at a temperature of 23° C. at least equal to 4.0 MPa and hysteresis losses tan(?)max greater than 0.19, a second material M2, on the edge parts, having a secant modulus at 10% elongation, measured at 23° C., lower than that of the first material, and a hysteresis losses value tan(?)max lower than that of the first material and at least equal to 0.15, a third material M3, radially below the materials M1 and M2, having a hysteresis losses value tan(?)max lower than 0.

Abstract: An object of the present invention is to provide a pneumatic tire having low rolling resistance and higher resistance against irregular wear. To achieve the above object, a pneumatic tire includes a tread portion comprising a plurality of block arrays each of which is constituted of a plurality of blocks that are partitioned by a plurality of main grooves extending in a circumferential direction of the tire and a plurality of lateral grooves crossing the main grooves, wherein at least one of the block arrays is provided with a thin rib that continuously extends in the circumferential direction of the tire in a central area of the block array as viewed in a width direction of the tire and is partitioned by two sipes extending in the circumferential direction of the tire, the depth of the sipes extending in the circumferential direction of the tire is 0.7 times or less of the depth of the lateral grooves.

Abstract: A pneumatic tire with a designated rotational direction comprises a tread portion, a pair of center circumferential main grooves extending on both sides of a tire equatorial plane, a center land portion between the center circumferential main grooves, a ripe provided with the center land portion, a plurality of V-shaped grooves each provided separately in the center land portion, each V-shaped groove having a peak located in a middle area of the center land portion, the first inclined portion extending from the peak to one side edge of the center land portion, and the second inclined portion extending from the peak to the other side edge of the center land portion, and a first inclined sub-groove and a second inclined sub-groove provided between a pair of V-shaped grooves, the first inclined sub-groove and the second inclined sub-groove being provided separately in the circumferential direction of the tire.

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: A pneumatic tire comprises a tread portion provided on each side of the tire equator with a land zone defined between two circumferential main grooves, wherein the land zone is provided with axial grooves extending between the main grooves and inclining to a first circumferential direction at an angle of from 30 to 50 degrees with respect to the tire axial direction, and auxiliary grooves inclining to a second circumferential direction opposite to the first circumferential direction. The axial groove is shallow in its axially-inner-main-groove side in comparison with its axially-outer-main-groove side. The auxiliary groove is deep in its axially-inner-main-groove side in comparison with its axially-outer-main-groove side.

Abstract: A studless tire capable of exhibiting excellent performances on both icy road and snow-covered road, including tread portion 2 having a pair of middle circumferential grooves 3b each extending in a region between 15% and 25% of tread width TW from tire equator C to provide crown region CR between the middle grooves 3b and a pair of shoulder regions Sh between the middle groove 3b and ground contact edge E, wherein the crown region CR includes rows R1, R2 of blocks B having sipes S and defined by zigzag inner circumferential grooves 3a and crown lateral grooves 4a, 4b, each shoulder region Sh includes rows R3, R4 of blocks B having sipes S and defined by linear outer circumferential grooves 3c and shoulder lateral grooves 4c, 4d, and groove area rate Gs (%) of shoulder regions Sh is larger than groove area rate Gc (%) of crown region CR so that the difference (Gs?Gc) is from 3 to 7%.

Abstract: A pneumatic tire capable of improving drainage performance and noise-reduction. The pneumatic tire comprises a tread portion being provided with central longitudinal grooves 3a, shoulder longitudinal grooves 3b, and intermediate land portions 4a each defined between the central longitudinal groove 3a and said shoulder longitudinal groove 3b. The intermediate land portion 4a is provided with a thin groove 5 extending the tire at a position away axially inside from the shoulder longitudinal groove 3b, intermediate slant grooves 6 each extending from the thin groove 5 toward said central longitudinal groove 3a while inclining terminating without being connected to the central longitudinal groove 3a, and connection grooves 7 each extending so as to connect between the adjacent intermediate slant grooves 6 in the circumferential direction of the tire. Each of the connection groove 7 inclines in the same direction as the intermediate slant groove 6 at an angle smaller than that of the intermediate slant groove 6.

Abstract: A tire contour shape is formed by a single arc in a condition in which tire flattening rate is more than 55% and less than 70% and internal pressure is 5%. Shoulder lateral grooves extend at an angle ? of 80 to 90° from the axially outer side of the tread ground-contact edge to the axially inner side of the tire, and the tire axially inner ends terminate within the shoulder land portion. A tire axial distance Ds between the tire axially inner end and the shoulder circumferential main groove is in the range of 3.5 to 5.5 mm, the shoulder lateral groove has the deepest part where the groove depth is largest, and the groove depth of the deepest part is 70 to 90% of the groove depth of the shoulder circumferential main grooves.

Abstract: A pneumatic tire according to the present invention improves wet performance. The pneumatic tire has a tread surface 1. A first main groove 2 extending in the circumferential direction TC of the tire is provided in the tread surface 1. First lateral grooves 7 extending from the first main groove 2 outward in the widthwise direction of the tire beyond one ground contact end TX1 of the tire are disposed at prescribed intervals in the circumferential direction TC of the tire. Blocks 8 are defined by the first main groove 2 and the first lateral grooves 7. The first lateral grooves 7 comprise inner groove portions 7A and outer groove portions 7B. The inner groove portions 7A extend with their widths gradually increasing from the first main groove 2 outward in the widthwise direction of the tire to midways of the first lateral grooves 7.

Abstract: A studless tire capable of suppressing a vehicle from staggering at the time of braking on icy and snow-covered roads, including a tread portion 2 provided with at least six block rows R1 to R4, wherein each block B is provided with sipes having a depth of at least 3.0 mm, and the block rows comprises at least two crown block rows CR disposed in a crown region Ac extending from the tire equator C as its center to have a width of 50% of the tread width TW, and at least two shoulder block rows Sh disposed on each axially outer side of the crown block rows CR, and wherein lateral grooves 4 provided in a block row are inclined in the opposite direction, with respect to the axial direction, to lateral grooves provided in an axially adjacent block row.

Abstract: A vehicle wheel tire center tread region has a repeating circumferential array of first substantially V-shaped grooves positioned on the centerplane, each first V-shaped groove having divergent first groove side arms extending in a first circumferential direction, and a repeating circumferential array of second substantially V-shaped grooves positioned on the centerplane and having divergent second groove side arms extending in a second circumferential direction opposite to the first circumferential direction. Each first V-shaped groove is overlapped by multiple oppositely directed second V-shaped grooves. The first V-shaped groove arms have a varying lengthwise depth that varies between about 2 and 7 millimeters from a shallower depth proximate to a vertex arm region to an increased depth at a medial arm region to a decreased depth at a terminal arm region.

Abstract: Tire tread comprising a plurality of elements forming relief, each element comprising a contact face, a plurality of elements of the tread being provided with at least one incision, this incision opening onto the contact face in order to form second edges parallel with one another and with an average orientation at most equal to 45° with the direction of the axis of rotation of the tire provided with this tread, each incision also opening onto two lateral surfaces of the element so as to form strips having a length L and a width d, this width d being less than the length L, each strip comprising at least one cavity entirely contained in the strip and of which the largest dimension is oriented so as to be in the direction of the length of the strip inside which it is formed, each cavity having a length Lc, measured along its largest dimension, which is between 10% and 90% of the length L of the strip, the total of the lengths Lc of all the cavities of one and the same strip being more than 10% of the length L

Abstract: Two open sipes are formed at a tire circumferential direction central side of a block, and closed sipes are formed in the block at both tire circumferential direction sides of the two open sipes. The depth of the open sipes is set in a range of 50 to 70% times the depth of a first circumferential direction main groove, and the depth dimension of the closed sipe is set in a range of 105 to 140% times the depth dimension of the open sipes. Accordingly high performance on ice is obtained while securing block rigidity.

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 tread is configured to have three rows of tread elements, a center row and a pair of shoulder rows, the center row forming a circumferential rib positioned at an equatorial centerplane of the tread. Each shoulder row has a repeating circumferential array of upwardly extending elongate groove fingers, adjacent groove fingers within the repeating array of each shoulder row of groove fingers being connected by at least one laterally extending channel. An array of serrations line each longitudinal side of the channels, each serration defined by inward tapering serration sidewalls extending to a serration base surface. Each channel is submerged below an outward tread surface such that the submerged channel will emerge as the tread wears down.

Abstract: A pneumatic vehicle tire for commercial utility vehicles has a tread with at least two circumferential grooves which run in the circumferential direction and divide the tread into circumferential ribs. A gross tread volume is defined by an envelope running in the tread parallel to the periphery of the tread and touching the lowest circumferential groove(s) from the inside radially, together with the periphery of the tread and flank portions at the shoulders. A groove volume is defined by all the grooves in the tread. The groove volume in the tread is between 1% and 10% of the gross tread volume.

Abstract: A heavy-duty tire comprises a tread portion provided with at least three circumferentially continuously extending ribs divided by at least two circumferential grooves extending straight in the tire circumferential direction, wherein the ribs have side edges adjacent to the circumferential grooves; each of the side edges is provided with edge sipes at intervals in the tire circumferential direction; each of the edge sipes extends parallel with the tire axial direction from the adjacent circumferential groove and terminates in the rib; each of the edge sipe has an axial length in a range of not less than 5% but not more than 15% of the axial width of the rib, a thickness in a range of not less than 0.3 mm but not more than 1.0 mm and a depth in a range of not less than 50% but not more than 100% of the depth of the circumferential groove; and the total number of the edge sipes per tire is in a range of from 4 to 8 times the value of the tire diameter in millimeter.

Abstract: A tread (1) comprising a plurality of grooves of longitudinal and transverse general orientation (2b, 2c, 31, 32), the grooves of longitudinal orientation comprising main grooves (2b, 2c) of depth G and secondary grooves (31, 32) of depth G? less than the depth G of the main grooves, the central part (C) of the tread, defined axially by two grooves of longitudinal orientation, and of a width of between 0.25 and 0.5 times the width W of the tread, being provided with at least one main groove (2c) of longitudinal orientation and of average depth G. The depth G? of the secondary grooves (31, 32) is between 0.4 and 0.6 times the depth G of the main grooves (2b, 2c). The transverse grooves (5c) of the ribs of the central part (C) comprise over at most half of their length a connecting bridge (6c), the surface radially to the outside of which is at a distance Hc from the running surface of between 0.4 and 0.8 times the depth G of the main grooves.

Abstract: A pneumatic tire comprises main grooves 1 extending in the tire circumferential direction formed in a tread, wherein the main groove 1 has a plurality of narrow grooves 11 in its sidewalls 3, an end portion 11a of the narrow groove 11 on the tread side does not open to the tread surface and is located closest to the tread side, an end portion 11b of the narrow groove 11 on the groove bottom side does not open to the groove bottom 1b of the main groove 1 and is located closest to the groove bottom side, a length L1 of the narrow groove 11 measured in the depth direction of the main groove is 50 to 80% of a depth D of the main groove 1, the narrow groove 11 has at least one or more bend portions 21, and a length L2 of the narrow groove 11 measured along the narrow groove 11 itself is not less than 1.03 times and not more than 2 times L1.

Abstract: A circumferential sipe extends continuously in the circumferential direction of the tire in the center region of the tread surface section of a rib defined between circumferential grooves. Widthwise sipes are disposed at prescribed intervals in the circumferential direction of the tire in the tread surface section, the widthwise sipes extending in the widthwise direction of the tire in crossing relationship to the circumferential sipe, the widthwise sipes each having opposing terminal ends open to the circumferential grooves. The circumferential sipe changes in depth periodically in such a manner that the circumferential sipe is shallow between adjacent widthwise sipes. The widthwise sipes changes in depth in such a manner that they are greater in depth in the center region and end regions of the tread surface section.

Abstract: In a pneumatic tire in which a tread with a plurality of grooves 1 and 2 including main grooves 1 extending in the tire circumferential direction formed and in which block 3 is formed on shoulder portions of tread T by grooves 1 and 2, on intersection line L between a surface of tread T and a surface of side portion S, the first sipes 11 extending in the tire circumferential direction R are formed, and the depth direction of the sipes 11 and 12 is parallel to tire equatorial plane C, and the sipes 12 are deeper than the sipes 11 and the sipes 12 are wider than the sipes 11, and height difference between a surface of wearing region 13 and a surface of side portion S is not greater than 2.0 mm.

Abstract: A pneumatic tire has a unidirectional tread pattern comprising right-hand and left-hand crown circumferential grooves and a crown rib formed therebetween. The crown rib is provided with first and second V-shaped grooves arranged alternately in the tire circumferential direction. The first V-shaped grooves extend from the left-hand crown circumferential groove. The second V-shaped grooves extend from the right-hand crown circumferential groove. The first and second V-shaped grooves are terminated within the rib, and their V-shape configurations have bending points substantially positioned at the tire equator.

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: An object of the present invention is to provide a pneumatic tire that ensures both of the on-ice braking performance and the dry braking performance. In order to achieve the object, a pneumatic tire comprises a tread surface including a land portion in which a plurality of sipes are formed, wherein each of the sipes includes a reference plane extending in a depth direction of the sipe from a wavy or zigzag line in the surface of the land portion and each of the sipes is formed with a convex portion having a convex shape in a vertical section with respect to the reference plane in a top area at the front side and the rear side thereof.

Abstract: A heavy duty tire comprises a tread portion provided with a center rib, shoulder ribs and middle ribs therebetween. The middle ribs are provided with closed-end sipes. The sipe comprises: an axially inner segment and axially outer segment inclined at an angle of from 30 to 60 degrees with respect to the tire circumferential direction; and a middle segment therebetween inclined in a direction crosswise to the axially inner and outer segments. The angle ?1 between the axially inner segment and middle segment is from 90 to 110 degrees. The angle ?2 between the axially outer segment and middle segment is from 90 to 110 degrees. The axial length SW of the closed-end sipe measured from the axially inner end to the axially outer end thereof is from 0.50 to 0.90 times the axial width LW of the middle rib.

Abstract: Five land portions on tread surface are demarcated by four main grooves that extend in a tire circumferential direction TC. The five land portions include a center land portion between the first main grooves, two middle land portions between the first main grooves and the second main grooves, and two shoulder land portions located toward the outside of the second main grooves in the tire width direction, and sub-grooves and sipes are formed on the land portions. The total groove surface area ratios of the sub-grooves and the sipes in the land portions are different in the center land portion and the shoulder land portion as compared to the middle land portion, with the total groove surface area ratio being lower in the center land portion and the shoulder land portion and being higher in the middle land portion.

Abstract: An object of the present invention is to provide a pneumatic tire on a tread surface of which hand grooving can be carried out swiftly and easily, and a method of carrying out the hand grooving thereon. In order to achieve the object, a pneumatic tire comprises a tread surface formed with a plurality of grooves. The tread surface includes a guide line previously disposed as a reference for carrying out hand grooving. The guide line extends along at least one edge line of the grooves or a virtual extension line of at least one edge line of the grooves.

Abstract: In a pneumatic tire for a front wheel, turning performance on a wet road surface is improved compared with a conventional tire. In a pneumatic tire for a front wheel 10, a tread shoulder region 28S extends from a tread edge 20E toward a tire equatorial plane across a width of 20% of a developed width of a tread 28, and a land portion 56 defined by lateral portions 50 is disposed at the tread shoulder region 28S. Regarding the land portion 56, a wall surface 56K of the land portion at a trailing side is parallel to the tire radial direction; a wall surface 56H of the land portion at a leading side inclines from a groove bottom toward a groove opening, and an angle thereof relative to the tire radial direction is 35 degrees. It is effective especially for circumferential leaning deformation of the land portion 56 when braking force acts thereon, whereby lifting of an edge of the land portion at the leading side arisen from the tilting deformation can be suppressed.

Abstract: A thin groove 4 that continuously extends in the tread circumferential direction is provided in a shoulder rib 3. An annular groove 8 continuous in the circumferential direction is provided in a groove wall 4a on the tread equatorial surface side of the thin groove 4 to be contiguous to the groove bottom, in a cross section taken in the width direction of the tread.