Abstract: This invention is concerned with a radial tire, particularly a heavy duty radial tire aiming at the improvement of durability, and is characterized by rendering a ratio W2/W1 of width W1 of a belt layer located side a carcass to width W2 of the remaining belt layer in small slant belt layers arranged at a width corresponding to 0.25-0.50 times a tread width in a widthwise direction of the tire, whereby growth and progress of cracks in the vicinity of cord ends of cords used in the belt resulting in separation failure at widthwise ends of the belt are effectively prevented to overcome a weak point in the tread reinforcement of the radial tire.

Abstract: Reinforcement ply N for a tire, formed of reinforcement elements embedded in coating products, characterized in that it comprises a first C1 and a second C2 layer of metallic elements E1, E2 parallel to one another, embedded in a coating product or coating products M1, M2 and, between the said two layers C1 and C2, a third layer C3 of elements E3 made from a textile material and embedded in a coating product M3, the said textile elements E3 being orientated relative to the elements E1 and E2 at an angle between 70° and 110°.

Abstract: In a pneumatic radial tire comprising a belt of at least two belt layers, in which the belt comprises a maximum-width belt layer containing many cords slantly arranged with respect to an equatorial plane of the tire and a narrow-width belt layer arranged at the outside of the maximum-width belt layer in the radial direction and containing many cords arranged in an oppositely inclined direction to the cords of the maximum-width belt layer, the belt end separation is controlled by arranging a reinforcing layer containing many cords arranged in an oppositely inclined direction to the cords of the maximum-width belt layer so as to overlap with an outer end portion of the maximum-width belt layer located outward from an outer end. of the narrow-width belt layer in the widthwise direction thereof.

Abstract: It is to provide a pneumatic tire in which a bulk modulus of elasticity of a tread rubber is small and an inverse V-shaped bending in a tread portion is suppressed to effectively prevent separation failure, breakage and the like of a belt layer, which comprises a radial carcass, a belt of two belt layers with a cross cord arrangement reinforcing a tread portion at an outer peripheral side of a crown portion of the radial carcass and a rubber reinforcing layer having a crescent-shaped form at a cross section, wherein the tread rubber forming a ground contact face of the tread is made of rubber having a bulk modulus of elasticity of not more than 4 GPa and an additional belt layer of cords having a cord angle with respect to an equatorial plane of the tire larger than that of cords in each of belt layers is arranged on an outer peripheral side of the belt and a compression rigidity of the additional belt layer in a widthwise direction of the tread is made 2 times or more larger than that of the belt layer.

Abstract: A method for designing tires for reduced cavity noise is directed to tires of the type having architectural elements comprising at least one carcass structure anchored in each side of the tire in a bead, each bead having a base which is intended to be mounted on the tire's design mounting rim, a side wall portion extending radially upward from each bead, a reinforced summit comprising reinforcement cords disposed at a given angle, and the side wall portions joining the summit. The method includes the step of arranging the architectural elements to provide a flexibility level of at least a portion of the summit to allow said portion to vibrate at a frequency substantially corresponding to the cavity mode.

Abstract: In a pneumatic radial tire comprising a belt of at least two belt layers, in which the belt comprises a maximum-width belt layer containing many cords slantly arranged with respect to an equatorial plane of the tire and a narrow-width belt layer arranged at the outside of the maximum-width belt layer in the radial direction and containing many cords arranged in an oppositely inclined direction to the cords of the maximum-width belt layer, the belt end separation is controlled by arranging a reinforcing layer containing many cords arranged in an oppositely inclined direction to the cords of the maximum-width belt layer so as to overlap with an outer end portion of the maximum-width belt layer located outward from an outer end of the narrow-width belt layer in the widthwise direction thereof.

Abstract: A two-piece tire assembly has a removable tread belt 12 for installing about the circumference of a tire carcass 14. The tread belt has at least a pair of belt layers, and one layer comprising inextensible reinforcing cables inclined at substantially zero degrees relative to the circumferential direction of the tire assembly. The cables in zero degree ply have a tensile strength of at least 50,000 N.

Abstract: A chip resistant pneumatic tire (10) is provided. The tire has an original reinforced rubber sheet (22, 22b) embedded in or under its tread (18) and/or sidewall (20 ), and is used in off the road applications such as mining. Low sulfur rubber (17) is used to coat the organic reinforcement (11), and its shown that such rubber (17) is more compatible with rubber used to form the tread (18) or sidewall (20), which together with the organic reinforcement (11), helps prevent chipping and chunking in the tread (18) and sidewall (20). The illustrated organic filaments of cords (11) have a round cross section and are at least 2000 denier (2200 dTex) and have a tenacity of at least 3.5 g/denier (31 cN/Tex), an initial modulus of at least 20 g/denier (177 cN/Tex), an elongation at break of at least 10%, and a shrinkage of at most 10%.

Abstract: A radial motorcycle tire comprises a tread portion with a pair of tread edges, a pair of sidewall portions, a pair of bead portions each with a bead core therein, and a band disposed in the tread portion and composed of windings of at least one cord wound at an angle of not more than 5 degrees with respect to the tire equator. The tread portion is provided radially inside the band with at least two layers of cords comprising a radially outermost first layer and a radially inner second layer next to the first layer, wherein with respect to the tire equator, the cords of the first layer are inclined to a direction at an angle of from 65 to 90 degrees, and the cords of the second layer are inclined to the same direction as the first layer at an angle of from 65 to 90 degrees.

Abstract: A radial medium radial truck (RMT) tire has belt or breaker plies which are reinforced by organic reinforcement cords or filaments. In the preferred embodiment, organic multifilaments are used in the top belt or breaker plies which have the following characteristics: at least a gauge of 420×2 dTex to about 3300×3 dTex, a tenacity of about 35 cN/Tex to about 200 cN/Tex, an initial modulus of at least 30 g/denier (250 cN/Tex) and a shrinkage of about 0.1-10 %. When an organic polymer reinforcement is used in the top belt or breaker in the belt package of a tire, scrapping of tires during a retreading operation because of corrosion is greatly reduced. In addition, acceptance for retreadability is increased because of reduced top belt or breaker damage, allowing for easier preparation for the retreading. Moreover, the invention relates to an improved construction to reduce defects known as blows.

Abstract: A tire for heavy equipment, having at least one radial carcass reinforcement surmounted radially to the outside by a crown reinforcement formed of at least three so-called working plies formed of inextensible metal cables, crossed from one ply to the next, forming angles of between 15° and 35° with the circumferential direction. At least one half-ply, formed of inextensible metal cables and of width L′, on either side of the equatorial plane XX′, is arranged between the edges of at least two radially adjacent working plies, the cables of said half-ply forming with the circumferential direction an angle, which is firstly greater in absolute value than 25°, and secondly is greater in absolute value than the largest angle formed by the elements of the two working plies by an amount between 5° and 15°.

Abstract: A tire having a preferential fitting direction to a passenger car, the tire having a carcass reinforcement that extends from one tire bead to the other and, radially outside, a crown reinforcement of width Ls, formed by at least two crown plies, and in addition a meridian reinforcing ply arranged radially between the carcass reinforcement and the crown reinforcement, the meridian reinforcing ply having a width Lr between 15% and 45% Ls of the crown reinforcement, one edge of the reinforcing ply being located a distance D1 from the equatorial plane of the tire between 35% and 50% of Ls, while the other edge is located between the first edge and the equatorial plane of the tire. A method of mounting a group of four such tires on a vehicle.

Abstract: A tire includes a radial carcass reinforcement surmounted by a crown reinforcement formed of at least one working reinforcement having two plies of inextensible metallic reinforcement elements, parallel to each other within each ply and crossed from one ply to the next and forming with the circumferential direction angles &agr;1 and &agr;2 between 10° and 45,° and at least one protective ply. The axial widths L1 and L2 of the working plies and the axial width L3 of the at least one protective ply are such that L3<L2<L1. On either side of the equatorial plane XX′ of the tire is at least one additional ply of inextensible metallic reinforcement elements located in the plane of the protective ply and oriented in the same direction as the elements of the least wide working ply, which forms with the circumferential direction an angle &agr;4 greater in absolute value than the angle &agr;2 of the elements of the radially outer working ply by at least 5°.

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 radial tire comprises a radial carcass of at least one rubberized cord ply, a belt comprised of three rubberized cord layers, an innermost cord layer and a middle cord layer among these cord layers being a cross cord layer that cords of the layers are crossed with each other with respect to an equatorial plane of the tire, and one or more circumferential grooves provided in at least each side region of the tread portion, wherein the cords of each of the innermost cord layer and the middle cord layer have an inclination angle of 10-25° with respect to an equatorial plane of the tire, and cords of an outermost cord layer have an inclination angle of 45-115° with respect to the equatorial plane and the outermost cord layer has a width extending toward an end of the tread portion over an outermost groove edge of an outermost circumferential groove in a widthwise direction of the tread portion.

Abstract: A pneumatic radial ply tire (50) having a tread (52), a carcass (60) with two sidewalls (77, 78), two or more radial plies (70, 72), two annular beads (36a′, 36b′), a belt structure (56) located radially between the tread and the radial ply structure (58), one or more circumferentially deployed high-modulus incompressible belt reinforcements (66) and/or two or more circumferentially deployed high-modulus tensile-stress-bearing fabric reinforcements (59). Belt reinforcement(s) (66) and/or fabric reinforcement(s) (59) work to increase the lateral and circumferential rigidity of the tread (52) and underlying structures of the carcass (60). The lateral and circumferential stiffening of the tread (52) enhances high-speed runflat handling and contributes to improved runflat operational life.

Abstract: A tire whose crown has a ply of bimodulus reinforcements circumferentially oriented and spiral-wound, the ply being so arranged that, in the new tire, its reinforcements have a high-temperature contraction potential identical to that of the adhesive yarn before it is introduction in the tire. The tire has an appreciably diminished running noise.

Abstract: A tire having a radial carcass reinforcement, a crown reinforcement including at least two working crown plies of inextensible reinforcement elements, crossed from one ply to the other ply, forming angles of between 10° and 45° with the circumferential direction, and an additional, axially continuous, ply formed of continuous, inextensible and substantially radial metallic reinforcement elements made of steel, the additional ply being placed radially between the working plies, and having an axial width which is at least 1.1 times the axial width of the widest working crown ply.

Abstract: A tire having a form ratio under 0.80, a metallic radial carcass reinforcement, and a working crown reinforcement of two working plies formed of non-extensible reinforcement elements oriented at angles &agr; and &agr;′, with axial widths in the ranges between 0.65So to 0.80So and 0.35So to 0.45So, So being the maximum axial width of the median line of the carcass reinforcement, and two half-plies of non-extensible metallic elements making an angle &bgr; with the circumferential direction, where &bgr; is less than angles &agr;, &agr;′ by at least 2°, and is opposite to angle &agr; of the widest axially continuous working ply, the half-plies located on either side of the equatorial plane XX′ having axial widths between 0.22So and 0.35So, and axially inside edges separated from the equatorial plane XX′ by a distance equal to half the width of the narrower working ply less an amount of at least 0.05So.

Abstract: Disclosed is a radial tire for an automobile, in which lyocell having a dry/wet tenacity ratio S1/S2 of 1.2 to 1.6, a tensile strength at high temperature/a tensile strength at room temperature ratio S3/S4 of more than 0.8, and a shrinkage E of less than 0.01 is applied to a carcass part, thereby a resistance to fatigue and dimensional stability in running of a tire are improved.

Abstract: A radial medium truck (RMT) tire has belt or breaker plies which are reinforced by organic reinforcement cords or filaments. In one embodiment, organic monofilaments are used in the belt or breaker plies which have the following characteristics: at least 2,000 denier (2,200 dTex), a tenacity of at least 3.5 g/denier (31 cN/Tex), an initial modulus of at least 30 g/denier (265 cN/Tex) and a shrinkage of at most 6%.

Abstract: A heavy duty pneumatic radial tire comprises a radial carcass, a belt and a tread, wherein the belt is comprised of four or more belt layers, cords of adjacent two belt layers among these layers are crossed with each other with respect to an equatorial plane of the tire. In this tire, when a main cross belt is constituted with a widest-width belt layer and a wider-width belt layer in two belt layers adjacent to the widest-width belt layer, an inclination angle of cords in a neighboring narrower-width belt layer arranged at an outside of the main cross belt in the radial direction and adjacent thereto with respect to an equatorial plane of the tire is made larger than an inclination angle of cords in a belt layer arranged outward in the radial direction among the widest-width and wider-width belt layers.

Abstract: A tire with a radial carcass reinforcement of maximum axial width S0, including a crown reinforcement formed of at least two working crown plies of inextensible reinforcement elements, crossed from one ply to the other, forming angles of between 10° and 45° with the circumferential direction, the plies having axial widths greater than the width of an additional ply of inextensible, substantially radial, metallic reinforcement elements. The additional ply is arranged radially between the working plies, the working plies being, on either side of the equatorial plane and in the immediate axial extension of the additional ply, coupled over an axial distance at least equal to 3.5% of the width S0, then being decoupled by profiled members of rubber mix at least over the remainder of the width common to the two working plies.

Abstract: A cord for a tyre includes a strand of metallic core threads and at least two shells of metallic threads arranged around the core strand; the threads of the core strand and of the shells are wound helicoidally and have a “Lang Lay” type winding.

Abstract: A tire, comprising a radial carcass reinforcement surmounted by a crown reinforcement formed of at least one working reinforcement formed of two piles of inextensible metallic reinforcement elements, which elements are parallel to each other within each ply and are crossed from one ply to the next, forming with the circumferential direction angles &agr;1 and &agr;2 of between 10° and 45°, the working plies having axial widths L1 and L2, respectively, and at least one ply, referred to as a protective ply, of axial width L3, such that L3<L2<L1.

Abstract: A method of manufacturing a pneumatic tire comprises making a rubber-coated cord-member by coating one or more cords with rubber, and making the tread reinforcement by putting together a plurality of the cord-members around a drum into a cylindrical network of the cords, so that the cords make a first array of cords inclining in one direction with respect to the tire equator and a second array of cords inclining in one direction which is opposite to the cords of the first array with respect to the tire equator.

Abstract: A runflat pneumatic tire has a tread stiffening member radially inward of the tread 12. The tire has a deflected section height H30 under load at 30 psi inflation and a deflected section height H0 at 0 psi wherein the deflection D30 are equal to or less than D0−D30 and the net contact area at 0 psi has a perimeter dynamic contact shape of at least U shaped or rectangular.

Abstract: A motorcycle tire including a highly convex tread joined by two sidewalls of low height to two beads, each bead being reinforced by an inextensible annular element around which is anchored a carcass reinforcement formed of textile reinforcement elements forming with the circumferential direction an angle of between 70° and 90°, the carcass reinforcement being radially surmounted by a crown reinforcement formed of at least one ply of circumferential reinforcement elements, located radially between the carcass reinforcement and the radially outermost ply of the crown reinforcement, and of two plies of elements of textile material, which are crossed from one ply to the next and forming with the circumferential direction angles of between 65° and 85°.

Abstract: A pneumatic radial tire for passenger car comprises a circumferential belt layer in addition to a slant belt layer, in which specified PET, nylon, PEN or vinylon fiber cords or steel cords are used in the circumferential belt layer.

Abstract: A pneumatic radial tire for passenger cars comprises a circumferential belt layer in addition to a slant belt layer, in which specified PET, nylon, PEN or vinylon fiber cords or steel cords are used in the circumferential belt layer.

Abstract: A tire having a preferential fitting direction to a passenger car, the tire having a carcass reinforcement that extends from one tire bead to the other and, radially outside, a crown reinforcement of width Ls, formed by at least two crown plies, and in addition a meridian reinforcing ply arranged radially between the carcass reinforcement and the crown reinforcement, the meridian reinforcing ply having a width Lr between 15% and 45% Ls of the crown reinforcement, one edge of the reinforcing ply being located a distance D1 from the equatorial plane of the tire between 35% and 50% of Ls, while the other edge is located between the first edge and the equatorial plane of the tire. A method of mounting a group of four such tires on a vehicle.

Abstract: A pneumatic tire comprises at least one carcass ply of textile cords and a belt comprised of two cross belt layers containing textile cords arranged at a cord inclination angle of 10-45° with respect to the equatorial plane, in which a difference of cord inclination angle between the two cross belt layers with respect to the equatorial plane of the tire is within a range of 5-35° in the widthwise direction, and is mounted onto at least either left-side or right-side front wheel of a four-wheeled vehicle.

Abstract: A tire, the H/S form ratio of which is at most 0.6, formed radially from the inside to the outside by a triangulation ply of metal cables oriented at least 60°, two working crown plies formed of inextensible metal cables oriented at angles of between 10° and 45°, between which there is inserted a first additional ply of metallic elements which are oriented substantially parallel to the circumferential direction of the tire, a second additional ply being arranged, on either side of the tire, radially above the outermost working ply and substantially centered on the end of the first additional ply.

Abstract: A radial tire is provided with a metal belt comprising two load-bearing strips, respectively a first one and a second one, with reinforcing elements inclined in opposite directions in the two strips relative to the equatorial plane, and a pair of lateral bands radially superimposed on the ends of the second strip. The second strip has an axial width less than the first one and has edges staggered axially inwards with respect to the edges of the first strip. Each band comprises a single layer of circumferential metal reinforcing elements and has its axially external edge staggered axially inwards with respect to the edge of the second strip. A third strip with inclined reinforcing elements is arranged in the radially outermost position of the belt and covers at least two thirds of the width of each band. The pair of bands covers at least partially the two ends of the second strip in a diverging configuration relative to the two ends of the first strip.

Abstract: A pneumatic radial tire for passenger car comprises a circumferential belt layer in addition to a slant belt layer, in which specified PET, nylon, PEN or vinylon fiber cords or steel cords are used in the circumferential belt layer.

Abstract: A pneumatic tire comprises at least one carcass ply of textile cords and a belt comprised of two cross belt layers containing textile cords arranged at a cord inclination angle of 10-45° with respect to the equatorial plane, in which a difference of cord inclination angle between the two cross belt layers with respect to the equatorial plane of the tire is within a range of 5-35° in the widthwise direction, and is mounted onto at least either left-side or right-side front wheel of a four-wheeled vehicle.

Abstract: In a heavy duty pneumatic radial tire, at least one carcass layer is provided between right and left bead portions and at least two belt layers formed of steel cords which exhibit a breaking elongation of 4% or less are arranged in an outer periphery of the carcass layer in a tread portion. The belt layers are composed of at least one upper belt layer (A) and at least one lower belt layer (B). The upper belt layer (A) has a belt width that is 0.6 times or less a carcass line maximum width SW of the carcass layer at a tire section and the lower belt layer (B) has a belt width such that both end portions thereof extend to tread shoulder portions. An inclination angle of the steel cords of the lower belt layer (B) relative to a tire circumferential direction is set to be larger than that of the upper belt layer (A). A ratio (Mb.sub.2 .multidot.N.sub.2)/( Mb.sub.1 .multidot.N.sub.1) of a product of a bending rigidity Mb.sub.2 per steel cord of the lower belt layer (B) and the number N.sub.

Abstract: A radial motorcycle tire having improved lateral grip under camber with good stability, wherein the tread is reinforced by two main breaker plies comprising parallel reinforcing cords oppositely inclined with respect to the tire circumferential direction and a supplementary breaker ply is disposed radially outward of the main breaker plies and comprises a cord reinforced central ply portion and lateral outer side ply portions disposed on opposite sides of the central ply portion, said lateral side portions comprising rubber having no cord reinforcement.

Abstract: A tire for an airplane has radial carcass reinforcement surmounted by a cn reinforcement composed of at least three plies of textile reinforcing elements, including at least one twin zig-zag ply of two zig-zag plies "guided" at an angle .alpha., abbreviated to NT.alpha..degree., and at least one other "guided" ply, wherein the crown reinforcement comprises, at least between one twin zig-zag ply and one of the other "guided" plies, a decoupling intermediate layer of thickness e forming a radial distance of at least 1.0 mm between the cords of the radially lower ply and the cords of the radially upper ply surrounding the intermediate layer, the intermediate layer being formed of textile reinforcing elements coated in a rubber compound whose secant modulus of elasticity, measured at a relative elongation of between 0.06 and 0.2, is between 5 and 9 MPa.

Abstract: A heavy duty pneumatic radial tire comprises a radial carcass extending between a pair of bead cores, and a belt comprised of three rubberized cord layers, among which cord layers an innermost cord layer and a middle cord layer being laminated to form a cross belt layer by crossing cords of these cord layers with each other with respect to a plane including a circumference of the tire, in which an inclination cord angle with respect to the plane in the innermost cord layer and the middle cord layer is within a given range, and cords in an outermost cord layer have a given inclination cord angle as measured from the plane toward a direction of measuring the inclination cord angle of the middle cord layer, and a coating rubber for the outermost cord layer has a given modulus of elasticity.

Abstract: A tire with radial carcass reinforcement 1, having a crown reinforcement 3 aving at least two working crown plies 32, 34 made of inextensible cables, crossed from one ply to the other and forming angles of between 10.degree. and 45.degree. with the circumferential direction, characterized in that in the absence of any ply formed of inextensible cables forming an angle greater than 45.degree. with the circumferential direction, an additional, axially continuous, ply 33 formed of metallic elements oriented substantially parallel to the circumferential direction, is placed radially between the working plies 32, 34, having an axial width L.sub.33 at least equal to 1.05 times the axial width of the widest working crown ply L.sub.32, L.sub.34.

Abstract: A tire having an Heterologous/S form ratio of at least 0.50, having a rad carcass reinforcement (1) and crown reinforcement (3) composed of at least two working crown plies (31,33) made of inextensible metal cables, crossed from one ply to the next, forming angles of between 10.degree. and 45.degree. with the circumferentail direction, and of an additional ply (32) which is axially continuous and formed of metallic elements oriented substantially parallel circumferential direction. Said ply (32) over the working ply (31) radially closest carcass reinforcement (1,) and the ratio of its rigidity of extension per unit of width to the total of the rigidities of extension of the other plies of the crown reinforcement being between 0.35 and 0.70.

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 has at least two belt layers disposed at a tread portion thereof, wherein the two belt layers are constituted by inclining a strip formed by aligning a plurality of reinforcing cords to a tire circumferential direction and extending it zigzag in the tire circumferential direction so that the strip is turned back from the lower belt layer to the upper belt layer at both end portions of the two belt layers, and zone portions in which the reinforcing cords incline to the right in the tire circumferential direction and the zone portions in which the reinforcing cords incline to the left in the tire circumferential direction are alternately arranged.

Abstract: A metallic cord for the reinforcement of elastomers has a 4+3 construction wherein the diameter of each filament ranges from 0.35 to 0.50 mm. The lay length of the four filaments in the core may be infinity. A pneumatic tire has a belt structure of at least two radially overlapped layers of elastomeric materials reinforced with metallic cords, each metallic cord of at least one of the layers being the 4+3 metallic cord.

Abstract: A radial "heavy vehicle" tire, of H/S form ratio of at most 0.60, with a wn reinforcement (2) composed of at least two crossed working plies (21, 22), and at least one ply (20) of circumferential cables arranged above the carcass ply (1) and a tread (10) of width L, characterized in that there is arranged, between the ply of circumferential cables (20) and the first, radially innermost, working ply (21), a layer of rubber mix (4) of low modulus of extension, of constant thickness of between 2 and 3 mm.

Abstract: A pneumatic radial tire for passenger car comprises a circumferential belt layer in addition to a slant belt layer, in which specified PET, nylon, PEN or vinylon fiber cords or steel cords are used in the circumferential belt layer.

Abstract: The tire of this invention has a belt package with a combination of a steel refinforced inner belt ply and an aromatic polyamide reinforced outer belt ply. The strength per unit width of the aromatic polyamide reinforced ply is made to be within 30 percent greater than the strength per unit width of the steel reinforced belt ply. The tire of this invention has angles of the aromatic polyamide reinforcing members from the mid-plane greater than the angles of the steel reinforcing members from the same mid-plane by 1 to 8 degrees. High impact endurance values are disclosed to be a function of the difference in bending stiffness values for each ply as well as a function of the composite shear stiffness values.

Abstract: A radial pneumatic tire having excellent run-flat durability. The tire is equipped with a belt (4), which includes a plurality of metal cord layers, and a tread (5) successively placed at a periphery of a crown portion (3) of a toroidal radial carcass (2), and is equipped with, at an inner peripheral surface of the side portion (6) of the carcass, a rubber reinforcing layer (7) having a crescent moon shaped cross-section and bearing and supporting load. The tire has an auxiliary belt (8) disposed between the carcass and the belt and including organic fiber cords which are oriented substantially cross to the cords of the carcass and the cords of the belt with respect to a central equatorial plane, the cords of the auxiliary belt substantially crossing the central equatorial plane.

Abstract: The tire of this invention has a belt package with a combination of a steel refinforced inner belt ply and an aromatic polyamide reinforced outer belt ply. The breaking strength, tensile modulus, secant modulus and other material properties for the reinforcing members in each belt ply are defined. The strength per unit width of the aromatic polyamide reinforced ply is made to be within zero to 30 percent greater than the strength per unit width of the steel reinforced belt ply. The tire of this invention has angles of the aromatic polyamide reinforcing members from the mid-plane greater than the angles of the steel reinforcing members from the same mid-plane by 1 to 8 degrees. High impact endurance values are disclosed to be a function of the tensile modulus, breaking strengths and belt ply widths for each ply as well as a function of the composite shear stiffness values.