Abstract: A new pneumatic radial ply truck tire 10 for use on steering axles has a tread 12 with a pair of centerline grooves 14 and a pair of shoulder grooves 16 that divide the tread 12 into a pair of shoulder rows 24, a pair of riding rows 26 and a center row 28. Lateral grooves 20 divide the rows into block elements 22. The centerline grooves 14 and shoulder grooves 16 have top, middle and bottom potions 30, 32, 34 and 36, 38, 40. The top portions 30, 36 have straight sides 42, 48 that are angled at top angles A1, A2 respectively. The middle portions 32, 38 also have straight sides 44, 50 that are angled at middle angles A3, A4 respectively. To provide the grooves 14, 16 with a general V-shape, it is preferred that the middle angles A3, A4 be greater than their respective top angles A1, A2 respectively. The bottom portions 34, 40 are U-shaped and have bottom widths X1 and bottom depths D1, D2 respectively.

Abstract: A tire tread has a total of four circumferential ribs and three circumferential grooves. The four ribs include two intermediate ribs and two outer ribs, and the three grooves include a center groove and two outer grooves. The two intermediate ribs are between the center groove and the two outer grooves, and the outer ribs are on the opposite sides of the outer grooves from the intermediate ribs. Rib cross slots and cross sipes extend outwardly from the outer grooves into the intermediate and outer ribs in herringbone patterns. The cross slots and cross sipes extend less than the full width of the ribs to provide the intermediate ribs with circumferential inner portions adjacent the center groove that are devoid of cross slots. These circumferential inner portions of the intermediate ribs have a plurality of circumferentially-spaced cross sipes that do not intersect the center groove.

Abstract: A pneumatic tire has a tread portion with one circumferential wide groove extending continuously in the circumferential direction. A centroid of the cross-section of the circumferential wide groove deviates from the tire's equatorial plane so as to divide the tread part into a narrow tread section and a broad tread section. One of the groove walls extends along a curve convexed outwardly in the tire radial direction from one of the bottom edges of the circumferential wide groove and is smoothly connected to the outer surface of the tread portion. When the tire is mounted on a regular rim, inflated with regular internal pressure and applied with a normal load, the groove width GW of the circumferential wide groove is defined to be not less than 35 mm and not more than 0.35 times the ground contact width TW of the tread part.

Abstract: A pneumatic tire capable of obtaining a high tire performance on ice without decreasing the other performances can be provided. A plurality of narrow grooves each having a rectangular cross section are formed on one sipe side wall surface of a sipe in an inclined manner at a certain angle. Even when the sipe is closed under a load application to the tire, portions having the narrow grooves are not brought into contact with the other sipe side wall surface of the sipe so that water on an ice road surface can be absorbed and removed by the narrow grooves. Further, in the case of the narrow groove in which one end is opened to a road contact surface portion and the other end is opened to a side surface, the absorbed water can be continuously discharged to an outside of a block in serial order so that the water on the ice road surface can be further removed.

Abstract: A new pneumatic radial ply truck tire 10 for use on steering axles has a tread 12 with four circumferential grooves 14 that divide the tread 12 into a pair of shoulder rows 24, a pair of riding rows 26 and a center row 28. Lateral grooves 20 divide the rows into block elements 22. The centerline grooves 14 and shoulder grooves 16 have top and bottom potions 30, 32. The top portions 30 have straight sides 42 that are angled at top angles A1. The middle portions 32 also have straight sides 44 that are angled at bottom angles A2. To provide the grooves 14 with a general V-shape, it is preferred that the bottom angles A2 be greater than their respective top angles A1. Stone penetration protectors 34 are positioned within the circumferential grooves 34 to protect the tread 12 and the belt-package 13 from stone damage. The lateral grooves 20 that extend across the two riding rows 26 and the center row 28 have top portions 50 and bottom portions 52.

Abstract: A heavy duty pneumatic tire having improved resistance to uneven tread wear includes a tread portion provided with an axially outer longitudinal main groove and an axially inner longitudinal narrow groove, each extending circumferentially about the tire to define a narrow rib therebetween, the axially inner edge of the narrow rib being chamfered by a slope. In the tire meridian section, the slope is straight or concave. The axial width of the axially inner longitudinal narrow groove is in the range of from 0.5 to 2.5 mm. The axial width (W3) of the slope measured between the upper and lower edges thereof is in the range of from 0.3 to 0.8 times the axial width (W2) of the narrow rib, and the radial height (H2) of the slope measured between the upper and lower edges is in the range of from 0.3 to 0.8 times the depth (H1) of the axially inner longitudinal narrow groove.

Abstract: A pneumatic tire comprises a tread portion, the tread portion is provided in a center region with a row of long blocks and wide blocks which are disposed alternately in the circumferential direction of the tire, the center region has 30% of the tread width, the long blocks are such that the circumferential length (a) is larger than the axial length L1, the wide blocks are such that the axial length L2 is larger than the circumferential length (b), the ratio (a/b) of the circumferential length (a) and the circumferential length (b) is 1.1 to 1.5, and the ratio (S1/S2) of the surface area S1 of the long blocks and the surface area S2 of the wide blocks is 0.40 to 0.77. Preferably, the axial length L2 of the wide blocks is 18 to 30% of the tread width, and the long blocks and wide blocks are disposed such that at least one of the long blocks and at least one of the wide blocks appear in the ground contacting patch of the tire.

Abstract: The present invention provides a pneumatic tire having a tread portion comprising a plurality of axially spaced apart essentially longitudinal grooves separating essentially longitudinal ribs. On at least one of said ribs, transverse grooves or cuts repeat in the circumferential direction to form first and second land portions wherein the first land portions comprise blocks having a circumferential length greater than that of the second land portions. Said second land portion acts as a sacrificial bridge which provides traction improvement and minimizes undesirable surface anomalies during the service life of the tire.

Abstract: A tire is described which has a tread pattern provided with a large central channel (2) interposed between two continuous circumferential ribs (8), and a pair of large circumferential grooves (4) located at symmetrically opposite positions relative to the central channel (2). Also provided are transverse grooves (3) having a symmetrically converging inclined extension, the axial inclination of which increasingly grows larger towards the central channel (2). The longitudinal grooves (4) each consist of a sequence of oblique portions (4a) giving the grooves a broken-line course, so that each land portion or block (5, 6) delimited by the grooves (3, 4) has a corner (5a, 6a) projecting inwardly of the corresponding circumferential groove (4) with respect to the opposite corner (5b, 6b) of the circumferentially adjacent block.

Abstract: A heavy duty pneumatic radial tire having sub grooves provided on a tread surface which has a center main groove and two outer main grooves. The sub grooves extend in the tire width direction and together with the main grooves, divisionally form two block rows composed of a plurality of blocks. The sub grooves are inclined in a direction opposite to the tire rotating direction from the center main groove toward the outer main grooves. The inclination angle of the sub grooves is gradually and continuously reduced from a first inclination angle measured at the center main groove to a second inclination angle measured at the outer main groove. The first inclination angle is set in the range from 70 to 90.degree. while the second inclination angle is set in the range of greater than 30.degree. and less than the first inclination angle. Further, notched grooves can be provided dividing the shoulder areas of the tread surface into a plurality of blocks.

Abstract: A pneumatic tire comprises a tread portion which is provided with a plurality of circumferential grooves extending continuously in the tire circumferential direction to axially divide the tread portion into a plurality of land portions, at least one of the land portions is provided with sipes each extending across the full width of the land portion to have a pair of open ends, each of the sipes is provided therein with at least three tie-bars to provide the bottom of the sip with at least three shallow parts in the open ends and therebetween and at least two deep parts between the shallower parts, and the depth (h2) at the shallow parts is set in the range of from 0.2 to 0.8 times the depth (h1) at the deep parts.

Abstract: Vehicle tire and a metal sheet mold plate for forming the vehicle tire having at least one axial end section includes a tread that includes sipes running substantially axially in at least one of the axial end sections when viewed from the top (i.e., perpendicular to the tread surface). The sipes are corrugated to form corrugated ridges and valleys that are substantially straight lines diagonally inclined in an oblique plane parallel to the substantially axially running sipes. The substantially axially running sipes may include a first set of sipes and a second set of sipes. The corrugated ridges and valleys of the first set of sipes are oriented, with regard to a radially outward direction, to extend axially inwardly toward (i.e., toward a axial center of the tire). Conversely, the corrugated ridges and valleys of the second set of sipes are oriented, with regard to the radially outward direction, to extend axially outwardly (i.e., away from the axial center of the tire).

Abstract: A pneumatic tire comprising a tread portion having a plurality of blocks which are defined by inclined grooves and by a plurality of connection groves connecting with the inclined grooves or with the tread end, wherein the side wall portion of a block facing a first inclined groove coming into contact with the ground precedingly is more rigid than the side wall portion of the same block facing a second inclined groove coming into contact with the ground following the first inclined groove, and the side wall portion of the same block located at the inner side in the tire width direction is more rigid than the side wall portion located at the outer side in the tire width direction.

Abstract: A pneumatic tire comprises an improved tread portion provided with blocks, each block provided with a sipe, the sipe extending across the block to have a first open end and a second open end, the sipe comprising three components forming a generally Z-shaped configuration, whereby the two parts divided by the sipe are engaged with each other to increase the block rigidity.

Abstract: A tread pattern for motor vehicle winter tires having transverse grooves symmetrically converging toward an equatorial plane "X" of the tire. A pair of circumferential grooves (3) respectively defined by oblique stretches (3a) have an orientation converging toward the equatorial plane "X", in a direction opposite to the rolling direction "D" according to which the transverse grooves (2) converge. Grip hollows (6) of increasing width in a direction opposite to the rolling direction, are formed astride of each transverse groove (2), at two contiguous center blocks (4). A central separation cut (7) between the center blocks (4) defines therein separation walls (7a) arranged to come into mutual contact when in the ground contacting area.

Abstract: A studless tire comprises tread blocks having a narrow-width center portion, a heel-side increasing-width portion and a toe-side increasing-width portion, wherein the axial width of the block becomes minimum in the narrow-width portion and increases toward the heel edge and toe edge in the heel-side and toe-side increasing-width portions, and the minimum width in the narrow-width portion being in the range of from 0.5 to 0.9 times the average of the maximum width in the heel-side increasing-width portion and the maximum width in the toe-side increasing-width portion, whereby the stress produced in the block rubber when a braking force or driving force acts thereon increases the apparent block rigidity to decrease the block edge lifting and thereby uneven wear can be decreased.

Abstract: A fiber composite material in which short fibers, such as polyester short fibers, are added to a matrix, such as a cross-linked rubber matrix, is provided, wherein a heat shrinkage ratio of the short fibers is 8% or less at fiber composite material molding temperatures of 140 to 200.degree. C. Also provided is a pneumatic tire in whose tire tread the fiber composite material is used. Such pneumatic tires include pneumatic tires provided with a foamed rubber layer in a tire tread. The foamed rubber layer has an average cell diameter of 10 to 120 .mu.m and an expansion ratio of 3 to 50%. A solid phase rubber portion of the foamed rubber layer includes 5 to 55 parts by weight of carbon black, 55 to 5 parts by weight of silica, and 1 to 15 parts by weight of short fibers to 100 parts by weight of a diene-base rubber component including 70 to 20 parts by weight of natural rubber and 30 to 80 parts by weight of polybutadiene rubber. A surface of the tire tread has a hardness of 52 or less at 0.degree. C.

Abstract: A tread for motor-vehicle tires has a raised pattern formed of a plurality of shaped blocks 7 distributed in circumferential rows 3, 4, 5, 6 disposed in parallel and in side by side relation. The number of the shaped blocks 7 arranged in each row gradually increases while moving from the equatorial plane X--X to the axial outer side edges 1a of the tread 1. Thus a gradual increase in the longitudinal stiffness of the shaped blocks 7 is achieved on passing from the side edges 1a of the tread 1 to the equatorial plane X--X, which brings about a reduction in the mobility of said blocks on the road contact patch and lower rolling noise.

Abstract: A pneumatic tire for a passenger car wherein a plurality of grooves are disposed on a tread surface to define and form land portions, and kerfs which are open to the grooves at at least one of the ends thereof are disposed on the land portions. At least one stage of step portion is disposed in a step shape on at least one of the groove walls of the grooves, and a plurality of kerfs are disposed on the step portion with smaller gaps than those of the kerfs disposed on the land portions.

Abstract: A pneumatic tire comprises sipes in each land portion defined by wide-width grooves in a tread portion, in which a sipe corresponding to at least a part of these sipes comprises a pair of main portions slightly shifting to each other in the axial direction and a link portion connecting opposed end portions of these main portions to each other, and the pair of the main portions are inclined in opposite directions with respect to a radial direction so as to make a mutual distance L between the main portions large.

Abstract: A tire having a decreased percentage of void and superior wear abilities, yet still having improved wet traction ability is disclosed. The improved wet traction ability is enhanced by the flow isolating characteristic of the minor grooves of the tire. By reducing the amount of water flow between the major and minor grooves for a prescribed period during which the major grooves evacuate water away from the tire, there is a reduction in the volume and nature of turbulence due to the intersecting water flows exiting the minor grooves into the major grooves. This reduction of turbulence allows for fluid to be properly channeled away from the contact patch area by their major grooves.

Abstract: A pneumatic tire comprises a tread portion divided into at least three land portions by at least two circumferential main grooves, and at least one of the three land portions is provided with sub-grooves being shallower in depth than the main grooves and having a width in the range of from 0.05 to 0.60 times the width of the main grooves. The sub-grooves comprises axial sub-grooves extending across the land portion and a circumferential sub-groove extending continuously in the circumferential direction of the tire. The circumferential sub-groove is provided in the bottom with a circumferential sipe extending continuously in the circumferential direction of the tire. Each of the axial sub-grooves is provided in the groove bottom on each side of the circumferential sub-groove with an axial sipe extending along the longitudinal direction thereof.

Abstract: In order to improve the wear of the trailing edges of the relief elements of a tread (1) for "heavy vehicle" tires, which elements are defined in the axial direction by circumferential grooves and in the circumferential direction by incisions (30) of a width other than zero and at most equal to 3 mm, said incisions (30) are inclined with respect to the normal (P) to the surface of the tread by an angle .alpha. of between 5.degree. and 25.degree. so that the resultant force (F.sub.F, F.sub.M) exerted by the ground on the tread tends to straighten the incisions (30) towards a zero inclination. The inclination of the incisions (30) is particularly advantageous in the case of a tread (1) provided with "wide" circumferential grooves having a step (4). Application for steering, load-bearing or driving tires.

Abstract: A pneumatic studless tire comprises a tread provided with a plurality of circumferential grooves, a plurality of lateral grooves and many blocks defined by these circumferential grooves and lateral grooves, in which (1) a plurality of wave-shaped sipes are formed in each of the blocks so as to make them dense at central region of the block in the widthwise direction of the tire and sparse at both side regions thereof, and (2) an amplitude of the wave-shaped sipe in each side region of the block is smaller than that in the central region of the block.

Abstract: A pneumatic tire having a tread provided with at least one circumferential groove extending substantially parallel with the tire circumferential direction, and inclined grooves arranged at intervals in the circumferential direction of the tire, the inclined grooves being inclined at an angle with respect to the circumferential groove and the axial direction, and blocks formed by the circumferential groove and the inclined grooves and arranged at intervals in the circumferential direction of the tire, the blocks having acute angle corners formed by the circumferential groove and the respective inclined grooves, wherein (a) a sipe is formed near one of the acute angle corners which contacts the ground later in the block during tire rotating, the sipe having an opening at the circumferential groove or at a tread end, and (b) the sipe extends from the opening toward the inside of the block substantially parallel with the inclined groove and terminates in the block.

Abstract: A pneumatic tire comprises a tread portion provided with a pair of circumferential grooves and axial grooves extending from the circumferential grooves to tread edges, each of the axial grooves extending along a parabola of which the parabola axis extends parallel to the tire axial direction and the parabola vertex is disposed on the axially outer edge of the circumferential groove and the parabola focus disposed axially outward of the parabola vertex, and the axially outer edge of the axial groove extending on the parabola from the parabola vertex to the tread edge, whereby a flow of water is improved and thus a flow of air is also improved to improve wet performances without increasing tire noise.

Abstract: Two or three main grooves, which extend in the circumferential direction of a tire, are provided in the central ground contacting region alone of a tread surface of the tire the rotational direction of which is designated to one direction, and at least one rib extending in the circumferential direction of the tire is formed between the main grooves. A plurality of sub-grooves respectively extending from the both sides of the main grooves outward in the widthwise direction of the tire up to at least the ground contacting ends of the tire are arranged at a predetermined pitch in the circumferential direction of the tire in such a manner that the sub-grooves formed in zigzag lines are inclined with the inner end portions thereof positioned on the forward side with respect to the rotational direction of the tire. The sub-grooves do not communicate with the main grooves but communicate with land portions separated by the sub-grooves.

Abstract: A radial pneumatic light truck or automobile tire 10 having a tread 12 which has a plurality of traction elements 20,30 aligned in rows and separated by wide circumferential grooves 24 and a plurality of narrow laterally inclined grooves 26,36. Each traction element 20,30 is divided into at least three zigzag portions by a plurality of wavy patterned sipes 28,38. The wavy pattern of sipes 28 within the central rows of traction elements 20 are laterally extending. The wavy pattern sipes 38 in the shoulder rows are circumferentially extending. The preferred tire 10 has the laterally extending narrow grooves 26 being wavy and along with the wavy sipes 28 of a traction element 20 having peak amplitudes (A) aligned along a linear path (L) inclined at an angle .theta., relative to the equatorial plane (EP). Axially adjacent central rows of traction elements 20 are oppositely inclined.

Abstract: A pneumatic tire for a heavy load is provided which prevents irregular abrasion generated at the edge of land portions of the tire tread. An irregular abrasion preventing land portion is thus formed at the edge of a land portion, inside the shoulder edge of the tire, whereby the irregular abrasion generated at this portion is prevented.

Abstract: A pneumatic tire having improved wet traction has lugs containing sipes which change direction within the lug and tie bars in the sipes near each point where the sipes change direction. Siping, and the positioning of tie bars, provide means for minimizing the difference of the principle direction of lug stiffness between individual lugs. Also, a tire of the invention has 4 pitch ratios which are distributed around the tire so that extra large pitches are not located next to small pitches.

Abstract: Pneumatic tires according to this invention have a tread provided with blocks separated by circumferential grooves extending around the tread and lateral grooves crossing the circumferential grooves, the blocks being respectively provided with two lateral sipes, characterized in that the lateral end portions having small rigidity in block portions which are substantially separated by lateral sipes are reinforced by, for example, a platform. The invention has the effects of restraining block chipping in heavy duty tires and degrading of steering stability in passenger tires, and enhancing the performance on ice without degrading wet performance, by means of increasing sipe density and restraining lowering of the block rigidity.

Abstract: One each wide main groove is disposed on each side of a tire equator on a tread surface, the area interposed between these right and left two main grooves is used as ribs, two kinds of large and small sub-grooves having mutually different groove widths and extending from the main grooves to a ground contact end in a tire width-wise direction are disposed alternately in both outside areas of the main grooves throughout one circumference of a tire, and sub-main grooves extending in the tire circumferential direction are disposed between the main grooves and the ground contact end in the tire width-wise direction.

Abstract: A tire tread band for medium/heavy duty motor-vehicles having circumferential grooves confining three pairs of respectively center, intermediate and shoulder ribs. Respective tread blocks are defined along the center and intermediate ribs and they are confined by transverse cuts. The center cuts impart a cusp-shaped end conformation and a hollow-shaped end conformation to the respective blocks, and the shapes of said end portions mutually match. The intermediate cuts run in the linear extension of the center cuts to give the respective blocks a rhomboidal configuration. The tire can be alternately associated with a driving axle or a driven axle, by merely reversing its direction of rotation, so that the following results are selectively achieved: an increase in the traction capability by the intermediate blocks or an increase in the directional capability as a result of the mutual wedging between the center blocks at the ground-contacting area.

Abstract: A pneumatic tire provided with a tread pattern, said tread pattern including a wider circumferential straight groove dividing the tread into right and left sides and having 7-25% of the width of the tread, a pair of circumferential ribs provided adjacent to right and left sides of the wider circumferential straight groove, respectively and each having 2.5-15% of the width of the tread, and a pair of narrower circumferential straight grooves provided adjacent to and axially outside the circumferential ribs, respectively, and each having a groove width being 0.5 to 5% of that of the tread and a groove depth being 50 to 100% of that of the wider circumferential straight groove, wherein: each of the circumferential ribs is provided with a plurality of sipes extending obliquely relative to the circumferential direction while being spaced in the circumferential direction, a depth of each sipes being 25 to 100% of the groove depth of the wider circumferential straight groove.

Abstract: A tire tread (10) comprising at least some elements in relief, provided w at least one incision (1), each of the facing walls P of which has a surface in relief, formed of protrusions (2) and of cavities (3) arranged on opposite sides of a central wall surface M, each of such protrusions (2) and cavities (3) having, on said central surface (M), a quadrilateral base (b.sub.S, b.sub.C) and a vertex (S, O', A', B', C') spaced from said surface, the base b.sub.S of a protrusion (2) being completely surrounded by bases b.sub.C of cavities (3).

Abstract: This invention provides pneumatic tires having improved wet performance without degrading resistance to uneven wear. A pneumatic tire having a plurality of main grooves and a large number of sipes extending between adjacent main grooves and opening to both grooves is characterized in that the sipe has substantially uniform width in the depth direction at the both end portions opening to the main grooves, and has an expanded width portion at the bottom of the sipe at at least the greater part of the remaining portion except for the uniform width portion.

Abstract: A pneumatic tire for a heavy load is provided which prevents irregular abrasion generated at the edge of land portions of the tire tread. An irregular abrasion preventing land portion is thus formed at the edge of a land portion, inside the shoulder edge of the tire, whereby the irregular abrasion generated at this portion is prevented.

Abstract: A tire that has a tread base compound and a tread cap compound that have synergistic properties, an extra wide center rib, stiff shoulder lugs, and lateral grooves between shoulder lugs that do not vary significantly in width has a superior combination of rolling resistance properties, traction properties, noise properties, and wear properties. Also the RSAT of the tire can be fine tuned by chamfering edges of lugs in the tire.

Abstract: The present invention relates to a method of setting a tire tread pattern provided with grooves at angles with respect to a vehicle's direction of travel that enables the vehicle to run straight on a sloping road with good maneuverability. The invention also relates to a method for selecting a vehicle of a given weight that is equipped with a tire having a set tread pattern for preventing skewing.

Abstract: A pneumatic tire running on snow and ice roads has a tread pattern defined in a tread portion by a pair of circumferential grooves dividing the tread portion into a central region and both side regions, a great number of slant grooves arranged in the central region at a given interval in a circumferential direction of the tire and a plurality of zigzag sipes arranged at a given interval in the circumferential direction in each of blocks defined by the circumferential grooves and the slant grooves. In this tread pattern, first slant grooves having a particular small inclination angle and second slant grooves having a particular large inclination angle with respect to the circumferential direction are arranged so that the inclinations of the first and second slant grooves are opposite to each other, and at least one end of each of the zigzag sipes arranged in the same block is opened to the circumferential groove or the first slant groove.

Abstract: A pneumatic tire which is improved in uneven tread wear resistance without sacrificing the on-the-snow/ice running performance. The tread portion comprises a plurality of blocks, each provided with at least two sipes. Each sipe extends axially of the tire at an angle of from 90 to 88 degrees to the circumferential direction of the tire. In a cross section of the block parallel to the tire equatorial plane, each sipe extends radially inwardly from the radially outer surface of the block at an angle (.beta.) of from 2 to 10 degrees with respect to the tire radial direction so that the radially inner ends of the sipes inclining the same direction towards the rear surface of the block. The rear surface of the block inclines to the same direction as the sipes at an angle (.gamma.2) of not more than 30 degrees with respect to the tire radial direction but not less than the angles (.beta.) of the sipes. The front surface of the block inclines to the reverse direction to the rear surface.

Abstract: A heavy duty pneumatic tire, in which uneven tread wear is controlled, has a tread portion provided with a pair of main circumferential grooves so as to divide the tread portion into a pair of shoulder lands between tread edges and the main circumferential grooves and an axially inner land between the main circumferential grooves, each main circumferential groove having a width of from 4 to 12% of the tread width TW, a narrow circumferential groove extending circumferentially of the tire along one of the main circumferential grooves so as to divide the axially inner land into an axially outer narrow land part and an axially inner major land part, the axial width W1 of the narrow land part being in the range of from 0.1 to 0.2 times the axial width W2 of the major land part, the narrow circumferential groove having a width of 0.5 to 2.

Abstract: Pneumatic tire. The invention pertains to a vehicle tire for use in winter driving conditions whose tread pattern includes a circumferentially extending row in each of the shoulder regions, wherein the profile or pattern is asymmetrically shaped and includes, relative to the vehicle, an inner tread portion and an outer tread portion, with the shoulder block row of the inner tread portion being provided with sipes having good opening characteristics, with reference to the circumferential direction of the tire, and the shoulder block row of the outer tread portion is provided with sipes that assure high block rigidity during lateral force loading.

Abstract: A radial pneumatic light truck or automobile tire 10 having a tread 12 which has a plurality of traction elements 20,30 aligned in rows and separated by wide circumferential grooves 24 and a plurality of narrow laterally inclined grooves 26,36. Each traction element 20,30 is divided into at least three zigzag portions by a plurality of wavy patterned sipes 28,38. The wavy pattern of sipes 28 within the central rows of traction elements 20 are laterally extending. The wavy pattern sipes 38 in the shoulder rows are circumferentially extending. The preferred tire 10 has the laterally extending narrow grooves 26 being wavy and along with the wavy sipes 28 of a traction element 20 having peak amplitudes (A) aligned along a linear path (L) inclined at an angle .theta., relative to the equatorial plane (EP). Axially adjacent central rows of traction elements 20 are oppositely inclined.

Abstract: A pneumatic tire comprising a radial carcass, a belt and a tread portion is provided at its side end region of a ground contact area of the tread portion with a plurality of fine grooves, each being a groove in which each of opposed groove walls extends slantly in substantially a direction opposite to a rotating direction of the tire toward a groove bottom of the fine groove and considerably improves a straight running stability while controlling a wandering phenomenon during the running on slant road surface.

Abstract: A studless tire with a tread pattern comprising blocks that are defined by longitudinal and transverse grooves and having at least one row of blocks that extends in the peripheral direction of the tire. The peripheral rows of blocks are such that at least one sub-block is provided within one pitch of the tread pattern outside an adjacent block in the tire's rotating axle. And the sub-block is separated from the block by a sub-groove less deep than the longitudinal and transverse grooves and has the longer side in the peripheral direction and the shorter side in the direction of the rotating axle.

Abstract: A pneumatic tire in which the uneven wear resistance and durability are improved without sacrificing the on-the-snow performances. The tire comprises a tread portion provided with blocks each having a top surface of which the centroid is located within the ground contacting width, each block provided with circumferentially spaced axially extending sipes. In each block, the depths of the sipes gradually increasing from both the circumferential edges of the block toward the circumferential central portion of the block so that at least one deepest sipe exists in the circumferential central portion, and the maximum depth of the deepest sipe being in the range of from 0.6 to 0.9 times the depth of the circumferential grooves. Preferably, the depth of each sipe is gradually decreased from the axially inside to the outside of the tire.

Abstract: A tread for pneumatic vehicle tires comprising a central row of tread blocks extending in the circumferential direction of the tire and rows of tread blocks arranged in the shoulder regions of the tire is described. The rows of blocks arranged in the shoulder regions of the tire are separated from the central row of tread blocks by circumferential grooves. The edges of the tread blocks which laterally border the circumferential grooves extend inclined relative to the central circumferential plane of the tire. Wave-shaped sipes or knife-cuts are provided in the tread blocks with the tread blocks of the rows of blocks arranged in the shoulder regions of the tire being more pronouncedly divided or split by sipes than the tread blocks of the central row blocks.

Abstract: A pneumatic tire having a block design suited for off-road use, modified to improve rolling resistance and noise properties when used on paved surfaces, has a tread design having angled lateral grooves between the blocks in each circumferential row of blocks in the tread. Narrow grooves separate the blocks in several of the rows of blocks, and tie bars are present in the lateral grooves separating blocks in other rows of blocks. Void areas in the shoulder area of the tire enhance traction in mud and sand.

Abstract: A studless tire with a tread pattern comprising blocks that are defined by longitudinal and transverse grooves and having at least one row of blocks that extends in the peripheral direction of the tire. The peripheral rows of blocks are such that at least one sub-block is provided within one pitch of the tread pattern outside an adjacent block in the tire's rotating axle. And the sub-block is separated from the block by a sub-groove less deep than the longitudinal and transverse grooves and has the longer side in the peripheral direction and the shorter side in the direction of the rotating axle.