Abstract: A heavy duty radial tire which comprises a radial carcass ply, a belt comprising at least two plies of cords laid at angles of 10 to 40 degrees to the tire circumferential direction, and a tread portion provided with circumferentially extending two shoulder grooves which divide the tread into a central region and a pair of shoulder regions, the tread profile being a convex curve in the central region but a concave curve in each of the shoulder regions, the concave curve passing radially inwards of a standard line at lest partially, and the standard line defined as a circular arc passing three points on the tread profile in the central region at the tire equator, the axially inner edge of the main groove and the middle thereof. Preferably, the distances To, Tt and Tm measured normally to and radially outwardly from the standard line to the tread profile at the axially outer edge of the main groove, the tread edge and the deepest point therebetween, respectively, satisfy Tt>To>Tm.

Abstract: A vehicle tire which has an aspect ratio of less than about 55% and comprises a tread portion having a profile whose radius of curvature decreases substantially continuously from the tire equator to each tread edges. The tread profile from the tire equator to each tread edge is substantially defined by a curve such as ellipse, cycloid, epicycloid, involute curves and the like, of which equation is differentiable in the range between the tire equator and each tread edge.

Abstract: A high-transverse-curvature tire (1), in particular to be mounted on the front wheel of a motor-vehicle, comprises 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.

Abstract: A heavy duty pneumatic tire comprises a belt disposed radially outside a carcass and radially inside a tread portion, the belt comprising at least one ply of at least one high-elongation steel cord, the high-elongation steel cord being formed by twisting at least three waving steel filaments together to form a core and a sheath surrounding the core. The waving filaments change place repeatedly along the longitudinal direction of the cord such that one of the filaments forms the core in a portion, but in a different portion of the cord, the same filament forms part of the sheath, thereby defining a plurality of first parts with the core and a plurality of second parts without the core which are disposed alternately in the longitudinal direction of the cord. The elongation at break of the high-elongation steel cord is in the range of from 4 to 10%.

Abstract: A pneumatic radial tire capable of effectively controlling the occurrence of wandering phenomenon when being used in vehicles such as passenger car, small-size truck, truck, bus and the like is provided, in which a second tread zone contacting with a mountain side of a slant road surface is arranged so as to project toward a side of a first tread zone contacting with a flat road surface and camber thrust of the radial tire is increased by the second tread zone during the running on ruts and the like under loading.

Abstract: A pneumatic radial tire comprises a breaker belt disposed radially outside the carcass having at least two cross plies of high elastic modulus cords laid at an inclination angle of from 15 to 30 degrees with respect to the tire equator, and a band belt disposed radially outside the breaker belt and comprising a full-width band and a pair of axially spaced edge bands, wherein the full-width band is made of low elastic modulus organic fiber cords arranged substantially parallel to the tire equator. The edge bands are made of high modulus organic fiber cords arranged substantially parallel to the tire equator, whereby the high speed durability and cornering performance are improved.

Abstract: A pneumatic vehicle tire has a carcass with at least one radial ply and beads having bead cores, whereby the carcass is anchored to the bead cores. A multi-ply belt is positioned radially outwardly on the carcass, and a tread is positioned radially outwardly on the belt. Sidewalls extend between the tread and the beads. The sidewalls have a first portion extending from the beads outwardly at an angle of 0% to 20% relative to the axial direction of the tire. The sidewalls have increased stiffness within the area of 50% to 90% of a tire height measured in a direction from the bead to the tread. The area of 50% to 90% prevents the sidewalls from touching the road surface when the tire is deflated and compressed.

Abstract: A runflat radial ply passenger or light truck pneumatic tire 10 has a carcass 30 reinforced with at least one sidewall insert or filler 42 and one substantially inextensible cord reinforced ply 38, the ply being wrapped about two bead cores 26 and located radially inward of a belt reinforcing structure 36. The sidewall insert or filler 42 is located radially inward of the ply 38. The cord 43 has a minimum modulus E of 10 Gpa and is generally inextensible and less heat sensitive than conventional synthetic cords used in passenger and light truck tires.

Abstract: A very light weight tire 10 has at least one radial ply 38 and a fiberglass belt structure 36 covered by an overlay 59 having cords 80 selected from the group of aramid, rayon, PEN, PET and PVA. The tire 10 has a very thin or reduced gauge (t) undertead 13. The tire 10 can be made having very low rolling resistance due to the combination of casing structure and the reduced rubber mass.

Abstract: A very light weight tire 10 has at least one radial ply 38 and a aramid belt structure 36, having two single cut belt layers 50,51 covered by an overlay 59 having cords 80 selected from the group of aramid, rayon, PEN, PET and PVA. The tire 10 has a very thin or reduced gauge (t) undertead 13. The tire 10 can be made having very low rolling resistance due to the combination of casing structure and the reduced rubber mass.

Abstract: A rubber filler in the tire bead portions is formed by a hard rubber filler having JIS A hardness of at least 85, and a soft rubber filler having JIS A hardness of 65-75. An outer end C of the interface between the hard and soft rubber fillers is placed to be higher than the upper end of a rim flange and at least 10 mm lower than an end D of a turned-up steel cord carcass, in a cross section of the bead portion of the tire. Further, 1.0 La.ltoreq.Lb.ltoreq.2.0 La, where Lb represents the distance B-E from an inner-surface-side end B of the interface between a rubber bead cover and carcass topping rubber of a carcass ply to an inner-surface-side end E of the interface between the hard and soft rubber fillers, and where La represents the distance D-A from the end D of the turned-up carcass to an outer-surface-side end A of the interface between the rubber bead cover and the carcass topping rubber.

Abstract: A tire having a decreasing profile diameter includes an outside sidewall with a greater height than the inside sidewall. The inner diameters of each sidewall are preferably identical. The outer diameter of the outside sidewall is greater than the outer diameter of the inside sidewall. The cross-section of the width of the tread has a substantially constant thickness from the inside tread diameter to the tread surface of the tire. The depth of the tread is preferably constant across the width of the tread surface.

Abstract: A pair of high-transverse-curvature tires for two-wheeled vehicles is provided, in which the belt structure of the rear tire comprises a layer of inextensible cords disposed at a substantially zero angle with respect to the equatorial plane of the tire, preferably wound on a sheet of elastomeric material reinforced with aramid pulp, whereas the belt structure of the front tire comprises at least one radially outer layer of inextensible cords disposed at a substantially zero angle with respect to the equatorial plane of the tire and distributed with an axially variable density, and preferably another reinforcing layer at a radially underlying position. The zero-degree cords preferably are metallic cords of the high-elongation type, made of high-carbon steel.

Abstract: A method of manufacturing a radial tire is disclosed, wherein a tread ring is formed separately from a tire main body by the use of a tread ring forming apparatus. The radial tire comprises a belt having a camber and a band wound thereon. The tread ring is an annular assembly of a raw belt, a raw band wound thereon and a raw tread rubber. The tread ring forming apparatus comprising a belt drum made up of segments defining the drum circumference. In a cross section including the belt drum axis, the radially outer surface of each segment is a straight line parallel to the axis. In a cross section normal to the belt drum axis, the radially outer surface is an arc having one radius substantially equal to one half of the drum diameter, but the drum circumference is decreased in the belt edge portion than the central portion by increasing gaps between the segments.

Abstract: A pneumatic radial tire has a carcass extending around the tire from bead-to-bead, sidewalls and a rubber tread region which has a profile, when considered in transverse cross section, of a new tire terminating at the sides of the tread in inner and outer shoulder regions, respectively, each shoulder region having a shoulder drop, which is the distance, in the radially inward direction, from the point of maximum tire diameter to a point of the shoulder at the edge of the shoulder region, such that when the tire is mounted on a scheduled wheel rim and inflated to a scheduled pressure, the tread region is asymmetric, having its point of maximum tire diameter offset in the axial direction of the tire from the center line of the tire section in the direction of the inner shoulder, and the shoulder drop of the outer shoulder is greater than the shoulder drop of the inner shoulder such that the tread region has an asymmetric profile, wherein the tread region has a substantially constant tread gauge or thickness exc

Abstract: A pneumatic radial tire comprises a carcass comprising an outer carcass ply made of cords having a first heat-shrinkage-percentage K1 and an inner carcass ply is made of cords having a second heat-shrinkage-percentage K2 different from the first heat-shrinkage-percentage K1, and the cord tension of the inner carcass ply is smaller than the cord tension of the outer carcass ply. A method of making the tire comprises steps of making the outer carcass ply of cords having a first heat-shrinkage-percentage K1, making the inner carcass ply of cords having a second heat-shrinkage-percentage K2, wherein the first heat-shrinkage-percentage K1 at 150 degrees C. is 120 to 160% of the second heat-shrinkage-percentage K2 at 150 degrees C., and heating and vulcanizing a raw tire to heat-shrink the outer carcass ply cords in a larger degree than the inner carcass ply.

Abstract: A pneumatic tire having an aspect ratio of not more than 55% comprises a carcass composed of a single carcass ply, in which a turnup end portion of the carcass ply is disposed between an end portion of a belt and a crown portion of the carcass ply, and distances L.sub.1 and L.sub.2 from a central position of a bead core to an outer end of a bead filler and to a maximum width of the carcass in the radial direction of the tire satisfy a relationship of L.sub.1 .gtoreq.L.sub.2 and within given ranges with respect to a section height (H) of the tire, respectively.

Abstract: An organic fiber cord for rubber reinforcement satisfies relationships of S1.gtoreq.2.5, S2.ltoreq.1.8 and S2.ltoreq.S1-2.0 wherein S1 and S2 are dry heat shrinkage factors under particular conditions in order to improve the durability and dimensional stability of rubber articles without the degradation of other properties in the rubber article. When such an organic fiber cord is applied to a carcass ply of a pneumatic radial tire, the tire durability and uniformity are considerably improved.

Abstract: A front tire for-wheeled vehicles comprising a carcass of toric form having a high transverse curvature and provided with a central crown and two sidewalls terminating in a pair of beads for anchoring to a corresponding mounting rim, a tread band located on the crown and a circumferentially-inextensible belt structure disposed between the carcass and tread band. The belt structure at a radially external position is comprised of a layer of cord coils substantially disposed at a zero angle to the equatorial plane of the tire in axial side-by-side relationship and extended from one axial extremity of the belt to the other axial extremity of the belt. The winding thickness of the cord coils increasingly grows from the equatorial plane to the belt axial extremities.

Abstract: A vehicle tire and wheel assembly for use in high brake heat generated service has an overall tire diameter (TD) of approximately 43 inches and an overall wheel diameter (WD) of approximately 24.5 inches to provide a ratio of approximately 1.76. The tire section height (H) is approximately 9.2 inches and the tire section width (W) is approximately 11.5 inches. The tire is of a radial construction containing steel reinforcing cords.

Abstract: The invention relates to a run-flat low inflation pressure all terrain vehicle (ATV) tire 10,11, wherein the tire 10,11 has at least one pair of elastomeric inserts 42,46, one insert 42,46 extending radially inward from each tread edge 14,16 toward a bead core 26. The radially inner end of the insert is radially inward of an elastomeric apex 48 located above the respective bead cores 26. The bead cores 26 have a wide substantially flat radially inner base which when the tire 10,11 is mounted on a conventional ATV design rim enable the tire 10,11 to remain seated onto the rim even when operating without any inflation. The preferred tire 10,11 has a unique tread 12. The central portion 13 of the tread 12 has circumferential rows of blocks or lugs 94. The lugs of laterally adjacent rows in a central region 13 of the tread 12 are connected by tie bars 93 which when employed on these run-flat tires keeps the tread lugs 94 in ground contact even when the tire is operated uninflated.

Abstract: A pneumatic radial tire for use in truck and bus comprises a carcass reinforcing a sidewall portion and a tread, and a belt comprised of at least two belt layers, wherein when the tire is mounted onto an approved rim and inflated under an internal pressure of 0.5-1.0 kgf/cm.sup.2, a carcass line of the carcass at a radial section of the tire comprises a curve having a maximum radius of curvature in a region ranging over 10-50% of a tire sectional height and centering around a position of a maximum carcass width, and the sidewall portion has a maximum thickness in a zone corresponding to the above region.

Abstract: A pneumatic radial tire capable of effectively controlling the occurrence of wandering phenomenon when being used in vehicles such as passenger car, small-size truck, truck, bus and the like is provided, in which a second tread zone contacting with a mountain side of a slant road surface is arranged so as to project toward a side of a first tread zone contacting with a flat road surface and camber thrust of the radial tire is increased by the second tread zone during the running on ruts and the like under loading.

Abstract: A rolling assembly is formed of a tire P with radial carcass reinforcement (1), the equilibrium curve of the thickness center line of which is tangent to the bead cores (2), and of a rim J comprising, axially to the outside of each seat (20) a flange R formed of a frustoconical portion (23) having a generatrix forming an angle of between 20.degree. and 60.degree. with a direction parallel to the axis of rotation, which is connected axially to the inside to the rim seat by an S-shaped portion and which is extended axially towards the outside by a cylindrical portion (25), in its turn extended by the curved end (26), the rim J having an axial width A equal to at most 0.65 times the maximum axial width S of the tire mounted on its rim and inflated to its pressure of use.

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: A pneumatic radial tire having an excellent resistance to uneven wear is provided by optimizing a crown profile of a tread portion, in which at least a radial half section of the crown profile with respect to an equatorial plane of the tire is divided into center and middle and shoulder regions and comprised of a composite arc formed by smoothly connecting at least three arcs having different radii of curvature to each other and each of distances and radii of curvature of these regions satisfies a particular relation.

Abstract: A pneumatic radial tire has a tread profile comprising a curved crown part having a radius of curvature R1, a pair of curbed middle parts having a radius of curvature R2 and a pair of curved shoulder parts having a radius of curvature R3 which extend continuously without forming any inflection point, wherein the radius R1 is in the range of from 2.0 to 3.5 times the tread width TW and is less than the radius R2 and more than the radius R3, and the camber quantity T1 which is the radial distance of the tread profile at the tread edges from the tread profile at the tire equator is 0.038 to 0.050 times the tread width TW.

Abstract: A tire (1), a mounting rim (2) therefor and a circumferentially unstretchable ring (3) for supporting the tread (10) of the tire when running at low or zero pressure. The tire (1) has a radial ply casing (13) on which the points that are furthest apart axially are radially apart close to seats (12B) of outwardly sloping beads (12). The seats (12B) engage sloping seats (23', 23") on the rim (2), which may have at least one mounting well (22), at least one cylindrical portion (21) for receiving the supporting ring (3) and a rim flange (24).

Abstract: A steel cord for the reinforcement of rubber article has a three-layer twisting construction comprising a core layer comprised of a single steel filament, a first sheath layer comprised of six steel filaments and a second sheath layer comprised of steel filaments subtracted by 1 or 2 filament from maximum steel filament number arranged on a circumscribed circle of the first sheath layer without a wrap filament. In this steel cord, filament diameters of the core layer and the sheath layers satisfy the particular relationships. The steel cord is used in a carcass ply of a heavy duty pneumatic radial tire.

Abstract: A heavy duty radial tire is to be mounted on a 15 degree drop center rim. In a mounted state that the tire is mounted on the rim and inflated to 0.5 ksc but not loaded, the inside diameter BC of the bead cores at the radially innermost point thereof is set to being not more than the diameter BT at the heel point of the bead portions. In a demounted state that the tire is demounted from a rim, the bead bottom is tapered towards the axial inside of the tire at an angle .theta. of from 1.0 to 1.9 times the angle .alpha. of the tapered bead seat of the rim. In the mounted state, the bead core has a radially inner surface tapered at the substantially same angle as the bead seat, and the axial distance BP of the axially inner end of this tapered inner surface from the bead heel point is set in the range of from 1.3 to 2.1 times the maximum width BW of the bead core measured in the direction parallel to the bead seat.

Abstract: A pneumatic tire in which sub-grooves extending at least in the widthwise direction of the tire are provided in a center portion of a tread surface and shoulder portions thereof on both sides of the center portion at a predetermined pitch, both the width and depth of the sub-grooves in the two shoulder portions being set larger than those of the sub-grooves in the center portion, a ratio of the area of the sub-grooves in the two shoulder portions to that of the tread surface being set larger than a ratio of the area of the sub-grooves in the center portion to that of the tread surface. This tire can be used with the air pressure therein set higher under the on-road travelling condition, and lower under the off-road travelling condition.

Abstract: A bias tire includes a reinforcement member disposed between a first carcass and an additional carcass in the crown region of the tire for restricting the circumferential growth of the tire. The reinforcement member includes a plurality of cords oriented at zero degrees. The total circumferential strength of the reinforcement member is about 20 to 250% of the circumferential strength of the carcass plies. The reinforcement member, first carcass, and additional carcass are formed on a tire building drum as a green tire component in a method of making the tire.

Abstract: An assembly is formed of a tire (1), a mounting rim (2), and an annular bearing support (3) for the tread (10) of the tire, for running at low pressure or at zero pressure. The rim (2) has two seats (23', 23"), the first seat (23') having an outwardly inclined generatrix and being axially outwardly extended by a shoulder or hump (25'), and the second seat (23") having an inwardly inclined generatrix and being axially outwardly extended by a flange (24). The tire (1) has a radial carcass reinforcement (13) with a particular meridional profile and two beads (12', 12") adapted to the mounting rim (2). The tread supporting ring (3) is ovalizable and circumferentially inextensible.

Abstract: A motorcycle tire comprises a tread reinforced between its edges by a breaker assembly and having in its normally inflated fitted condition a camber value C/L of between 0.5 to 0.7, a reinforcing carcass ply of rubber covered cords radially inside the breaker assembly and extending between two bead regions and wrapped in each bead region around an annular bead core to form carcass ply turn-ups, and tire sidewalls between the tread edges and bead regions, wherein under the tread is disposed radially inward of the breaker assembly a secondary carcass ply of rubber covered cords and between the carcass ply and the secondary carcass ply is disposed a rubber member extending from tread edge to tread edge.

Abstract: In order to improve the endurance of the crown reinforcement (3) of a tyre, he H/S form ratio of which is at most 0.6, the latter is formed radially from the inside to the outside by a triangulation ply (31) of metal cables oriented at at least 60.degree. and two working crown plies (32, 34) formed of inextensible metal cables oriented at angles of between 10.degree. and 45.degree., between which there is inserted an additional ply (33) of metallic elements oriented substantially parallel to the circumferential direction of the tire.

Abstract: A pneumatic tire comprises a carcass extending around the tire from bead to bead, sidewalls and a rubber tread region which has a profile when considered in transverse cross section of a new tire terminating the sides of the tread in inner and outer shoulder regions respectively, each of said shoulder regions having a shoulder drop, which is defined by the distance in the radially inward direction from the point of maximum tire diameter to a shoulder point at the edge of the shoulder region, wherein when the tire is mounted on a scheduled wheelrim and inflated to a scheduled pressure, the tread region has its point of maximum tire diameter offset in the axial direction of the tire from the center line of the tire section in the direction of the inner shoulder, and the shoulder drop of the outer shoulder is greater than the shoulder drop of the inner shoulder such that the tread region has an asymmetrical profile.

Abstract: A method of designing a pneumatic tire, wherein a basic model of a tire representing a cross-sectional shape of the tire including an internal structure, an objective function representing a physical amount for evaluating tire performance, a design variable for determining the cross-sectional shape of the tire, and a constraint for constraining the cross-sectional shape of the tire are determined. A corrected model of the tire with the design variable changed by a unit amount .theta.r.sub.i is determined. The value of the objective function and the value of the constraint in the corrected model are calculated. A sensitivity is calculated for each design variable, and an estimated value of the amount of change of the design variable which maximizes the value of the objective function while taking the constraint is calculated by means of the sensitivities. The above process is repeated until the value of the objective function converges.

Abstract: A pneumatic tire comprises a radially innermost belt ply having an axial width of from 0.8 to 1.2 times the tread width, a carcass with turnup portions having a radially outer end at a height of not more than 0.15 times the tire section height H, and a short fiber reinforcing layer having a thickness of from 0.3 to 1.0 mm disposed along the axially outer surface of the carcass in each of a pair of sidewall portions between the axial outer edge of the radially innermost belt ply and the radially outer end of the carcass turnup portion. The short fiber reinforcing layer is a compound of: 100 parts by weight of a base rubber compound containing 40 to 70 parts by weight of butadiene rubber and 60 to 30 parts by weight of natural rubber and/or isoprene rubber; 10 to 30 parts by weight of short fiber; and not more than 30 parts by weight of carbon black whose iodine number is in the range of from 30 to 90 mg/g.

Abstract: A pneumatic tire the aspect ratio of which is not more than 50% has, for reinforcing a tread portion, a belt comprising at least two rubber coated cord layers having cords arranged obliquely at angles with respect to an equatorial plane of the tire of 26.degree. or more, and a belt reinforcing layer arranged outside the belt and comprising at least one organic fiber cord layer having cords arranged substantially parallel with respect to the equatorial plane of the tire. The tire is molded in a mold with a cross-sectional profile of a molded surface facing the tread portion having a radius smaller than that of a nominal tire cross-sectional profile by 1% or more of a section width of the tire and forming a convex curve to a cavity.

Abstract: A pneumatic tire has a tread part with two wide circumferential grooves extending in either side of the tire's equator so as to divide the tread part into a pair of shoulder parts and a central part. The central part has a surface utilizing successive convex curves of a pair of inner groove walls and a central ground-contact surface. When the tire is mounted on a regular rim, inflated with regular internal pressure and applied with normal load, a ground-contacting area Fc where the central part contacts with the ground has a length Lc in the tire's circumferential direction which is 0.9 to 1.1 times a length Ls in the tire's circumferential direction of a ground-contacting area FS where the shoulder part contacts with the ground.

Abstract: A run-flat radial ply pneumatic tire 10 has a carcass structure reinforced with pairs of elastomeric sidewall fillers 42,46,48 and at least three bead cores 26,26' and 37. At least one bead core 37 lies axially between the lateral edges of the tread 12 and extends radially inwardly of the tread 12 and reinforcing belts 36 and radially outwardly of the first and second bead cores 26,26' and a carcass reinforcing structure 30. In several embodiments improved wet traction tread designs are employed.

Abstract: A new pneumatic radial ply truck tire 10 for use on steering axles is disclosed. The tire 10 has a 20 tread having a plurality of circumferentially continuous grooves 22, a pair of narrow circumferential decoupling grooves 24, a pair of radially recessed ribs 21, and a plurality of tread ribs 25,25A. The tread 20 has a radially outer tread surface 30 having a curvature defined by an internal radius of curvature Ri and an external radius of curvature Re, Re extending laterally over a majority of a shoulder rib 25A to the narrow decoupling groove 24 on at least one-half of the tread 20, preferably both tread halves. The shoulder rib 25A has a thickness (t) at the circumferential groove 22 which progressively increases to a thickness (t max) adjacent the narrow decoupling groove 24. The tread 20 exhibits a pressure distribution in the shoulder region which is complimentary to uniform wear.

Abstract: A pneumatic radial tire comprises a carcass comprising an outer carcass ply made of cords having a first heat-shrinkage-percentage K1 and an inner carcass ply is made of cords having a second heat-shrinkage-percentage K2 different from the first heat-shrinkage-percentage K1, and the cord tension of the inner carcass ply is smaller than the cord tension of the outer carcass ply. A method of making the tire comprises steps of making the outer carcass ply of cords having a first heat-shrinkage-percentage K1, making the inner carcass ply of cords having a second heat-shrinkage-percentage K2, wherein the first heat-shrinkage-percentage K1 at 150 degrees C. is 120 to 160% of the second heat-shrinkage-percentage K2 at 150 degrees C., and heating and vulcanizing a raw tire to heat-shrink the outer carcass ply cords in a larger degree than the inner carcass ply.

Abstract: A motorcycle radial tire comprises a tread reinforced between its edges by a breaker assembly and having in its normally inflated fitted condition a camber value C/L of between 0.5 and 0.7, a reinforcing carcass of radially disposed cords extending radially inside the breaker assembly and between two bead regions and wrapped in each bead region around an annular bead core from the axial inside to the outside to form carcass ply turn-ups, and tire sidewalls between the tread edges and bead regions, the tire characterized in that the breaker assembly comprises two breaker plies each reinforced with aromatic polyamide cords oppositely inclined with respect to the circumferential direction of the tire and a supplementary ply disposed radially adjacent to the breaker plies and reinforced with nylon reinforcements laid parallel to each other and disposed at an angle in the range of 75.degree.-90.degree. to the circumferential direction of the tire.

Abstract: A pneumatic tire for trucks, buses, etc. having a tread profile, before inflation, which has a first circular arc forming a tread center area and second circulr arcs forming shoulder ribs at both sides of the first circular arc, the first and second circular arcs intersecting together at a point from which the shoulder rib starts to extend and inwardly of which there is a 1/4 tread width point from a tread center axis, the first and second circular arcs having an inner radial divergence, between an inside wall top of an outermost main groove and the intersecting point, of up to 3 mm and an outer edge divergence, between an outer edge of the shoulder rib and an elongated line of the first circular arc, of up to 10 mm, whereby a good river wear resistance is attained.

Abstract: In a tire comprising two identical treads (1A) and (1B) reinforced by two own reinforcements (2A) and (2B) and separated by a connecting zone (6) formed of a groove (8) and a ring (7), the ring (7) has a curve representing the circumferential tensile load F as a function of the relative elongation .epsilon. which is non-linear, the ring (7) having for small relative elongations a circumferential tensile rigidity less than for larger relative elongations.

Abstract: A pneumatic tire having an improved tread profile capable of improving wet grip and running noise without sacrificing dry grip. The tread portion is provided with a pair of circumferential grooves to divide the tread portion into a central portion and a pair of shoulder portions. The contour of the central portion comprises a central face defined by a convex curve and a pair of side faces each defined by a concave curve. Each of the side faces extends axially outwardly and radially inwardly from each axial edges of the central face towards the bottom of the adjacent circumferential groove. The side faces intersects the central face to form an angle of less than 180 degrees. In a standard condition in which the tire is mounted on a standard rim, and inflated to 70% of the maximum air pressure, and loaded with 70% of the maximum load, the ground contacting width of the central portion is not greater than the axial width between the axial edges of the central face.

Abstract: A pneumatic radial tire comprising a tread portion, a pair of sidewall portions, a pair of bead portions each with a bead core therein, a carcass extending between the bead portions, a belt disposed radially outside the carcass and having a pair of edges, a rubber bead apex disposed in each bead portion and extending radially outwardly from the bead core, portions of the carcass one between each edge of the belt and the maximum tire width position are each provided therein with a rubber spacer disposed between axially adjacent carcass cords so that the cord spacing between the axially adjacent cords is in the range of from 0.55 to 5.5 times the diameter of the cords, whereby steering performance is improved without increasing the tire weight.

Abstract: A radial pneumatic tire comprises a pair of axially spaced apart beads. A radially reinforced carcass extends between and is secured at opposite end portions to the beads. The carcass includes a plurality of parallel extending reinforcing members. Each of the reinforcing members is disposed in a radial plane. A tread is located radially outward of a crown portion of the carcass. The tread is for engagement with a ground surface. A belt reinforcement package is disposed between the carcass and the tread. The carcass and belt package have particular profiles when the tire is properly inflated.

Abstract: A vehicle tire and wheel assembly for use in high brake heat generated service has an overall tire diameter (TD) of approximately 43 inches and an overall wheel diameter (WD) of approximately 24.5 inches to provide a ratio of approximately 1.76. The tire section height (H) is approximately 9.2 inches and the tire section width (W) is approximately 11.5 inches. The tire is of a radial construction containing steel reinforcing cords.