Abstract: A pneumatic tire of the invention includes: a stepped-shaped raised area provided in the main groove positioned at a center area of the tire so as to be continued circumferentially of the tire, connected to either the main groove walls, and raised from the groove bottom; and a ridge lower than a tread surface of the tire in each of the main grooves on both outsides of the main groove at the center area of the tire so as to be raised from the center of the groove bottom continuously along the length thereof without being joined with the groove walls, and the angle of inclination of the main groove walls with respect to the normal line of the tangential line on the tread surface of the main groove portion is parallel to each other or is 5° or smaller.

Abstract: A tread for a heavy vehicle tire, comprising at least one tread design component (3) delimited by at least two grooves, each component comprising a contact face (4) limited by edges (7, 8); the contact face (4) having, viewed in a cross-sectional plane substantially perpendicular to the contact face of the tread and cutting two of the edges of the motif at A1 and A2, a plot whose geometrical profile P between the points A1 and A2 has at least one bump (9, 10) in relief relative to a virtual straight line D passing through the points A1 and A2, the point B1, B2 of each bump (9, 10) that is furthest from the straight line D being located a height Hi from this straight line and a distance Di from the point A1 or A2 that is the closer, with 0.1<Di/L<0.25, where L is the distance separating the points A1 and A2, and 0.1 mm<Hi<2.5 mm.

Abstract: A pneumatic tire for dirt track racing comprising lateral and circumferential grooves forming blocks on the tread surface. The blocks have leading and trailing edge walls. The trailing edge walls of the blocks are buttressed by inclining the walls at an angle of 20°-60° relative to a line perpendicular to a tangent to the tread, and the edge wall extends into the groove by a distance of approximately one-half the tread width. The leading edge walls of the blocks have a radially outer portion inclined at about zero degrees and a radially inner portion have a radius of curvature of infinity or less, wherein the intersection point between the two portions is at about one-half the groove depth.

Abstract: A tire including a tread rubber having at least one positive profile. Wherein the positive profile is formed by at least one circumferential groove. Further, the tire includes at least one truncated groove extending into the positive profile from the circumferential groove, such that the truncated groove includes at least one flank surface. Further still, the tire includes the truncated groove being inclined at an acute angle to a direction of rotation of the tire. The tire includes a pitch of the flank surface that continuously changes with respect to the radial direction over a length of the truncated groove. The tire being a vehicle pneumatic tire. The instant abstract is neither intended to define the invention disclosed in this specification nor intended to limit the scope of the invention in any way.

Abstract: A tread surface, the tire rotational direction of which is specified in one direction, has a center region. Blocks having obtuse-angled corner portions and acute-angled corner portions are defined in the center region by at least one first circumferential groove extending in a circumferential direction of the tire on one side of the tire centerline, and first lateral grooves which extend outwardly in a widthwise direction of the tire from the first circumferential groove so as to incline towards a direction of reverse rotation of the tire and are disposed at predetermined intervals in the tire circumferential direction. Groove wall surfaces located on both sides of the obtuse-angled corner portion of each block facing to the first circumferential groove are inclined such that the inclination angles thereof are gradually greater towards the obtuse-angled corner portion and are maximum at the obtuse-angled corner portion.

Abstract: The present invention provides for an improved tire tread having an improved hydroplaning resistance. Specifically, the tread includes one or more tread blocks having one or more walls with an undercut surface to deviate the flow of water from a circumferential groove(s) to a lateral groove(s), thereby providing for improved worn hydroplaning performance of tires.

Abstract: To provide a pneumatic tire for a motorcycle in which both wear resistance and wet steering stability can be attained. Since a pair of zigzag circumferential direction grooves 28 are positioned at the center of a tread central region 24C and has an amplitude, even when a certain camber angle is exceeded, an occurrence of a sudden separation of the zigzag circumferential direction groove 28 from a road-contact surface 26 can be prevented, whereby deterioration of wet steering stability can be suppressed. When the camber angle increases, water in a road-contact surface 26 is drained by inclining grooves 32 which are arranged at an external side of the zigzag circumferential direction groove 28. Since sharp inclining groove portions 32A of the inclining grooves 32 are positioned in the tread central region 24C, and no lug groove components are employed, circumferential direction rigidities of land portions in the tread central region 24C are high and exhibits excellent wear resistance.

Abstract: A high-performance tire for a motor vehicle includes a carcass and tread band. The tire may be, for example, of the asymmetrical or directional type. The tread band includes a pattern including a central region, first and second shoulder regions, and first and second circumferential grooves. The first circumferential groove divides the first shoulder region from the central region, while the second circumferential groove divides the central region from the second shoulder region. The shoulder regions include shoulder blocks, separated from each other by transverse grooves, but joined to each other along axially inner ends of the shoulder blocks by respective circumferential portions. The central region includes rows of blocks and first and second annular projections or a central annular projection. The blocks of the central region, the shoulder blocks, the circumferential grooves, the transverse grooves, and the one or more annular projections help define the tread pattern.

Abstract: A pneumatic tire includes main grooves 1 extending substantially in a circumferential direction R of the tire, transverse grooves 2 connecting adjacent main grooves, and blocks 3 formed by adjacent main grooves and adjacent transverse grooves. Each block 3 has an acute corner portion 3a and an obtuse corner portion 3b and also has a groove side extending along the main groove 1 between the acute corner portion 3a and the obtuse corner portion 3b. An inclination angle a1 of the groove side increases from the obtuse corner portion 3b toward the acute corner portion 3a. An extending direction 1a of the main groove 1 at a tread surface level is inclined toward one side of the main groove 1 with respect to the circumferential direction R of the tire, while an extending direction of the main groove 1 at a groove bottom level is inclined toward the other side.

Abstract: An improved tire tread has tread elements which form a tread pattern exhibiting two or more peripheral grooves and a plurality of transverse grooves extending inward from the outer (ground engaging) surface of the tread. Preferably the transverse grooves extend across the peripheral groves, and there are at least four of the peripheral grooves. Along at least a major portion of one upper side of chosen ones of such grooves, the tread elements defining such groove side are formed with serrations extending inward of the groove from the tread surface at an acute angle to a radius of the tire and terminating short of the base of the groove. The serrated surfaces define an upper portion of the groove as an opening of increased area at the upper part of the groove intersecting the tread surface, and present a substantially increased traction area along the outer or open top of the groove.

Abstract: A pneumatic tire comprises a tread portion having a plurality of slant grooves, in which each slant groove has a steeply slant groove portion and a gently slant groove portion, and the steeply slant groove portion comprises a pseudo-land part of a given shape, and can improve a drainage performance without sacrificing the other tire performances.

Abstract: A vehicle having a profiled tread, having tread blocks (1) in at least some regions of its circumference, characterized in that for at least some of the tread blocks (1) at least the tread block edges (2) running into the tire contact patch (11) and extending at an angle to the central plane of the tire are lowered over their entire length with respect to the central plateau (3) of the respective tread block (1).

Abstract: A tire tread for a pneumatic tire has at least one circumferentially extending rib. The rib has a high siping density to provide flexibility to the rib. To provide support to the rib, circumferentially extending along, and attached to, the side of each rib is supporting chamfer.

Abstract: A tire tread for a pneumatic tire has a center rib and a series of steeply slanted grooves in each side region of the tread, the circumferentially adjacent grooves form blocks extending through the tread side regions. The center rib has a serrated configuration along each lateral side and a supporting chamfer extending from each serration point. Adjacent to each rib chamfer is a chamfer extending from the axially innermost point of the rib at the junction of two adjacent steeply slanted grooves. The rib is provided with high density siping. The tread blocks are siped wherein the siping density decreases from the tread center to the tread shoulders.

Abstract: A tire tread for a pneumatic tire has a center rib and a series of steeply slanted grooves in each side region of the tread, the circumferentially adjacent grooves form blocks extending through the tread side regions. The center rib has a serrated configuration along each lateral side and a supporting chamfer extending from each serration point. Adjacent to each rib chamfer is a chamfer extending from the axially innermost point of the rib at the junction of two adjacent steeply slanted grooves. The rib is provided with high density siping. The tread blocks are siped wherein the siping density decreases from the tread center to the tread shoulders.

Abstract: A pneumatic tire comprises a tread portion, a pair of sidewall portions, a pair of bead portions, a carcass extending between the bead portions, a breaker disposed radially outside the carcass, and a band disposed radially outside the breaker and composed of a full width ply extending across the substantially overall width of the breaker and a pair of axially spaced edge plies. In a ground contacting face of the tire under a normally inflate loaded condition which face has axially outermost edges between which the ground contacting width TW is defined, the circumferential length LS of the ground contacting face at an axial position 10% of TW axially inwards of each of the axially outermost edges is in a range of from 75 to 85% of the circumferential length Lc of the ground contacting face at the center of the ground contacting width.

Abstract: The invention is to improve wear resistance and resistance to crack growth of an off-the-road tire having a gauge of a tread rubber of 60-200 mm, in which a plurality of widthwise grooves extending substantially in a widthwise direction of the tire are arranged in each side region of the tread, and a pair of circumferential fine grooves continuously extending straight-forward or zigzag in a circumferential direction of the tire are arranged in a central zone of the tread, and a plurality of widthwise fine grooves extending substantially in the widthwise direction of the tire and contacting their grooves walls with each other in a ground contact area are arranged between these circumferential fine grooves.

Abstract: A high-transverse-curvature tire (1), in particular to be mounted on the front wheel of a motor-vehicle, which includes a belt structure (6) including, in a radially external layer (9a), a plurality of circumferential coils (7a), axially arranged side by side, of a cord (7) wound at a substantially zero angle with respect to the equatorial plane (X—X) of the tire. An area occupied by rubber blocks (10) formed in a portion of the tread band (8), having a length equal to the pitch (p) of the tread pattern and a width equal to the axial development of the tread band (8), is between 70% and 90% of the total area of the portion.

Abstract: A tire comprises a tread portion in which a mold parting line by a single-split mold runs on or near the tire equator. In a central part of the tread portion in which tread grooves are provided, the groove edges which are stroked by tire mold's protrusions for making the tread grooves when the mold is opened are provided with a chamfer backed by a recess and/or the groove walls extending from such groove edges are provided with a variable inclination, whereby demolding defects can be reduced.

Abstract: The tire of this invention has an asymmetrical tread pattern with a balanced inboard and outboard tread pattern. The tread pattern has a plurality of tread ribs with their average transverse widths equal to one another at the contact with the road surface. The total contact surface area on the inboard side of the mid-circumferential plane is essentially equal to the total contact surface area on the outboard side. The circumferential grooves between tread ribs have a groove base which is straight in the circumferential direction. The groove openings between the contact surface areas of adjacent ribs have a serpentine shape, except for the outermost outboard groove. The amplitude of the serpentine grooves increases from the outboard straight groove to the innermost inboard groove. The ribs have a rib base with a transverse width greater than the transverse width of each rib at the contact surface.

Abstract: A tire tread having grooves of transverse general orientation defining a plurality of blocks arranged so as to form a tread pattern having a preferred direction of travel, the blocks having a contact face, two lateral faces, a leading face forming an angle a greater than 90° with the contact face and a trailing face. For at least one tread pattern block, the trailing face of the block is formed of an upper part extending from the running face of the block which is extended towards the inside of the tread by a lower part. Furthermore, the upper part of the trailing face is undercut and forms an angle &bgr; of less than 90° with the contact face, whereas the lower part, which is inclined so as to form an angle &dgr; greater than 90° with the contact face, is provided with at least one recess which extends into the interior of the block.

Abstract: Disclosed is a pneumatic tire effectively controlling uneven wear occurring in the vicinity of a main groove even if a groove width of the main groove is widened due to change in tread radius during inflation. In the pneumatic tire, with regard to a zigzag-shaped main groove having the groove width widened during inflation among a plurality of main grooves provided on a tread surface, an inclination angle of a groove wall near the center with respect to the tread surface is made relatively large in a bent portion near the shoulder, an inclination angle of a groove wall near the shoulder with respect to the tread surface is made relatively large in a bent portion near the center, and regions where the inclination angles of the opposed groove walls are different from each other are uncontinuously arranged in the tire circumferential direction.

Abstract: In a high-transverse-curvature tire (1), in particular to be mounted on the front wheel of a motor-vehicle, comprising a belt structure (6) including, in a radially external layer (9a), a plurality of circumferential coils (7a), axially arranged side by side, of a cord (7) wound at a substantially zero angle with respect to the equatorial plane (X-X) of the tire, the area occupied by rubber blocks (10) formed in a portion of the tread band (8) having a length equal to the pitch (p) of the tread pattern and a width equal to the axial development of the tread band (8), is between 70% and 90% of the total area of said portion. Such a tire (1) advantageously couples a substantial reduction in the shimmy effect with a good wet grip and a reduction in both the braking distance and aquaplaning phenomena on wet road.

Abstract: A pneumatic tire comprises a tread portion provided with blocks, each block provided with circumferentially opening V-shaped corners each defined between two corner walls intersecting each other. In a cross section including the intersecting line K of the two corner walls and a normal line drawn normally to the tread face from a radially outer end of the intersecting line K, the intersecting line K comprising an upper slanting part KU and a lower normal part KL, the upper slanting part KU extending radially inwards from the tread face to a point P1 with an inclination angle &thgr;1 with respect to said normal line, and the lower normal part KL extending radially inwardly from the point P1 in substantially parallel to the normal line. The depth D1 of the point P1 from the tread face being in a range of from 0.30 to 0.50 times the height H0 of the block.

Abstract: Disclosed is a pneumatic tire effectively controlling uneven wear occurring in the vicinity of a main groove even if a groove width of the main groove is narrowed due to change in tread radius during inflation. In the pneumatic tire, with regard to a zigzag-shaped main groove having the groove width narrowed during inflation among a plurality of main grooves provided on the tread surface, an inclination angle of a groove wall near the shoulder with respect to the tread surface is made relatively large in a bent portion near the shoulder, an inclination angle of a groove wall near the center with respect to the tread surface is made relatively large in a bent portion near the center, and regions where the inclination angles of the opposed groove walls are different from each other are uncontinuously arranged in the tire circumferential direction.

Abstract: A tire having a ground contacting tread, the tread having a directional tread pattern comprising at least two substantially circumferentially extending grooves disposed one each side of the tread circumferential centerline and a plurality of circumferentially spaced apart and substantially axially extending shoulder grooves extending axially outwardly from each circumferential groove to the tread edge to define a row of tread blocks in each axially outer tread shoulder part, the axially extending grooves having two opposing inclined sidewalls which provide ramp support to the adjacent tread block edge, characterized in that each of the axially extending shoulder grooves has a groove depth which reduces from the axially inward part to towards the axially outer part, and each groove comprises two groove main portions connected end to end, each groove main portion having a varying asymmetric cross-section along its length, each groove main portion having a first groove sidewall having a constant first angle of i

Abstract: A pneumatic tire which comprises a pair of right and left bead portions, a carcass layer disposed extending between the bead portions, a tread portion arranged at an outside of the carcass layer in a radial direction of the tire, a pair of side wall portions arranged at right and left sides of the tread portion and at least one pair of rubber members selected from a pair of rubber members constituted with a rigid rubber and arranged in the bead portions and a pair of rubber members disposed in the side wall portions, wherein at least one pair of rubber members selected from a pair of rubber members arranged in the bead portions and a pair of rubber members disposed in the side wall portions are constituted with rubber composition having a minimum value of a dynamic storage modulus within a temperature range of 200 to 250° C. which is 75% of a dynamic storage modulus at 50° C. or more.

Abstract: A tread (1) for a tire with a preferred rolling direction, the tread having grooves (2) of substantially circumferential orientation which delimit ribs (30, 31, 32, 33, 35), at least one of which is provided close to each of its traverse edges with a plurality of incisions of width smaller than 1.5 mm. The incisions open onto the contact surface of the tread, are essentially parallel to one another, and having a mean inclination &agr; different from zero relative to the direction perpendicular to the rolling surface (S) of the tread.

Abstract: A pneumatic tire comprises a tread portion provided with a longitudinal main groove extending continuously in the tire circumferential direction and axial grooves each having at least one opening into the longitudinal main groove, and at least one of two groove walls of each of the axial grooves swells gradually towards the opening. The axial grooves include a groove having two openings and/or a groove having one opening and one closed end. The swelling part of the groove wall can be formed by a convexly curved surface extending from the tread surface towards the groove bottom, and having a single radius of curvature gradually decreasing towards the opening.

Abstract: A pneumatic tire includes a tread having a plurality of spaced tread blocks separated by grooves or slots. A plurality of tie bars extend across the grooves or slots between adjacent tread blocks. The tie bars have a pair of sidewalls and a top surface with an undercut formed in at least one of the sidewalls to reduce tie bar stiffness and provide increased water evacuation as the tread wears. The top surface of the tie bar is lower than the top surfaces of the adjacent tread block and the undercut can be formed in only one or both sidewalls of the tie bar and have various stepped and tapered configurations.

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 tread for a tire has a tread pattern embodying a plurality of blocks which are defined by cutouts of longitudinal and transverse general orientation, each block having a contact face and lateral faces, the intersection of each lateral face with the contact face forming a ridge, the ridge(s) which is (are) first to come into contact forming the leading edge of the element, the lateral face intersecting the contact face along the leading edge constituting the leading face, a plurality of blocks having leading faces which a taper at an angle at most equal to 5°. Each block is provided with a plurality of wells opening on to the contact face of said block, the average direction of each well forming an angle &bgr;1 at least equal to 10° with a line perpendicular to said contact face, the wells having average sections of between 0.2 and 12 mm2.

Abstract: A tire for vehicle wheels, provided with a tread band, includes a plurality of raised blocks confined between at least two longitudinal grooves, at least two transverse grooves meeting the longitudinal grooves, and a first and second series of sipes formed in the blocks to divide each block into a plurality of flexible portions. The flexible portions have a grip edge in the form of an acute angle on the outer rolling surface of the tread band. Each of the transverse grooves is confined between a first side, substantially normal to the outer rolling surface of the tread band, and a second side, diverging from the first side toward the outer rolling surface of the tread band. The second side of each of the transverse grooves has an orientation concordant with that of the sipes of a corresponding block, relative to the outer rolling surface of the tread band.

Abstract: A pneumatic tire which comprises a tread portion provided on each side of the tire equator with axial grooves extending axially inwardly from the tread edges, the axial grooves inclined to one direction with respect to the tire axial direction to form a non-directional tread pattern, and the inclination angle of the axial grooves to the tire circumferential direction is decreased from the axially outer end to the axially inner end thereof so as to have a minimum inclination angle &bgr;min of less than 45 degrees, and a maximum inclination angle of from 60 to 85 degrees. Preferably, the radially outermost belt ply has a cord angle a of 10 to 35 degrees to the tire equator and the axial grooves inclined in the reverse direction to the belt cords, and |&bgr;min−&agr;|≦25 degrees.

Abstract: A pneumatic tire including a tread portion provided with two circumferential grooves to divide the tread portion into a pair of shoulder parts and a central part therebetween, each of the circumferential grooves has such a relatively wide width that the maximum axial width (GWmax) thereof in the foot print is not less than 35 mm, and in a meridian section of the tire, the axially inner sidewall each circumferential groove is substantially straight and inclined axially inwards, and the axially outer sidewall of the circumferential groove comprises a convex part extending axially outwardly to a merge point at which the convex part merges into a ground contacting top surface of one of the should parts.

Abstract: A pneumatic radial tire comprises a radial carcass, a belt, and a row of many blocks having different lengths along a circumference of a ground contact region under pitch variation defined in a tread rubber of the tread portion by at least two straight main grooves and a plurality of lateral sub-grooves extending between the mutual main grooves at an inclination angle of less than 90° with respect to the circumference of the ground contact region, in which the block row satisfies such relationships that an inclination angle &phgr;L of an edge of a long-pitch block is larger than that &phgr;S of an edge of a short-pitch block and an inclination angle &agr;L of each block wall face of a long-pitch block is larger than that &agr;S of each block wall face of a short-pitch block, or further an inclination angle &bgr;S of a block wall face of a short-pitch block is larger than that &bgr;L of a block wall face of a long-pitch block.

Abstract: A high-transverse-curvature tire (1), in particular for mounting onto the rear wheel of motor-vehicles, comprises a tread band (8), coaxially extended around a belt structure (6), wherein a plurality of rubber blocks (10), defined between a plurality of grooves (1 1) extending along a direction substantially transverse to the tire running direction (D), are formed which grooves comprise a bottom (12) connected to opposite inlet (13) and outlet (14) sidewalls. In an equatorial zone (E) of the tread band (8), the inlet wall (13) of the grooves (11) is inclined with respect to the bottom (12) of the same towards the tire rolling direction, and forms an angle (&agr;) of from 50° to 80° with respect to a plane (&pgr;) tangent to the bottom (12).

Abstract: A tire comprises a tread portion in which a mold parting line by a single-split mold runs on or near the tire equator. In a central part of the tread portion in which tread grooves are provided, the groove edges which are stroked by tire mold's protrusions for making the tread grooves when the mold is opened are provided with a chamfer backed by a recess and/or the groove walls extending from such groove edges are provided with a variable inclination, whereby demolding defects can be reduced.

Abstract: A pneumatic tire comprises a tread portion provided with blocks, each block provided with circumferentially opening V-shaped corners each defined between two corner walls intersecting each other. In a cross section including the intersecting line K of the two corner walls and a normal line drawn normally to the tread face from a radially outer end of the intersecting line K, the intersecting line K comprising an upper slanting part KU and a lower normal part KL, the upper slanting part KU extending radially inwards from the tread face to a point P1 with an inclination angle &thgr;1 with respect to said normal line, and the lower normal part KL extending radially inwardly from the point P1 in substantially parallel to the normal line. The depth D1 of the point P1 from the tread face being in a range of from 0.30 to 0.50 times the height H0 of the block.

Abstract: At a portion of an inclined main groove from a tread center to an auxiliary groove of a pneumatic tire, an angle of inclination &thgr;1 of a groove wall surface at a block step-in end side is set to be smaller than an angle of inclination &thgr;2 of a groove wall surface at a block kick-out end side. Therefore, rigidity of step-in ends of blocks defined by inclined main grooves is lowered such that a striking sound can be reduced. Further, at a portion of the inclined main groove from the auxiliary groove to a tread end, an angle of inclination &thgr;1 of a groove wall surface at a block step-in end side is set to be greater than an angle of inclination &thgr;2 of a groove wall surface at a block kick-out end side. Therefore, rigidity of kick-out end sides of blocks defined by the inclined main grooves is lowered. Heel-and-toe wear which occurs at the kick-out end sides is suppressed, and an increase in pattern noise caused by heel-and-toe wear is suppressed.

Abstract: An agricultural pneumatic tire comprises a tread provided with many lugs extending at a given inclination angle from a central portion of the tread toward both ends of the tread and alternately arranged right and left with respect to an equatorial plane at given intervals in a circumferential direction of the tire, in which a side wall at a stepping-in side of the lug consists of a flat face slanted at a given angle with respect to a face perpendicular to the outer surface of the lug over a given distance from the outer surface and a bored face extending toward a root of the lug, and a side wall at a kicking-out side of the lug is a flat face slanted at a given angle with respect to the face perpendicular to the outer surface of the lug, and a ratio of circumferentially overlap component of the lug to circumferential length component is within a given range.