Abstract: A heavy duty pneumatic tire comprises a radial carcass, and a belt comprised of at least three belt layers, in which a first belt layer contains cords inclined at a large cord angle with respect to an equatorial plane of the tire and each of a second belt layer and a third belt layer contains cords inclined at a small cord angle with respect to the equatorial plane and cords of the second and third belt layers are crossed with each other. In the tire, the first belt layer is comprised of steel cords having a 1.times.N structure (N: 2-5) and/or each of the second and third belt layers is comprised of steel cords obtained by twisting 6 sheath steel filaments each having a filament diameter of not more than 0.30 mm around a single core filament at a twisting angle of not more than 6.degree..

Abstract: A pneumatic radial tire for passenger cars and heavy duty use is disclosed, which tire has a rubber coated steel cord layer in its belt portion. The cord consists of a pair of steel filaments whose preform ratio "K" is set in the range of 2.05-K.sub.1 .ltoreq.K.sub.2 <2.50-K.sub.1. Conformance to this preform ratio "K" provides filaments with periodically alternate contact and non-contact regions longitudinally of the cord.

Abstract: A cut resistant pneumatic tire is provided. The tire has a monofilament wire structure embedded in or under its tread or sidewall, and is used in off the road applications such as mining. The monofilament wire has a diameter of 0.4 to 1.2 mm and is made of brass plated steel. The wire may be woven or may have a spring link configuration. Two monofilament wires may be twisted together, and when two such wires are used, the total diameter is 0.8 to 1.4 mm.

Abstract: A pneumatic radial tire comprising a carcass and a belt comprising belt plies composed of steel belt cords wherein at least two circumferential grooves are constructed in the tread part continuously in the direction of the tire's equator, and lateral grooves in some parts defined by dividing the tread part in the direction of the tire's axis into approximately three or four equal areas. The tire prevents one-side drifting of a car in driving, improves a straight-forward driving performance.

Abstract: A pneumatic tire which is provided radially outside a carcass (6) with a belt (9) made of cords (10) embedded in topping rubber, each of the belt cords comprises four steel monofilaments (12A and 12B) including one or two waved steel monofilaments (12A) and unwaved steel monofilaments (12B), the four steel monofilaments having the same diameters are compactly twisted together so as to make alternate contact portions and non-contact portions (P) with a gap (T) between at least one waved steel monofilament and the adjacent steel monofilaments, and the four steel monofilaments have the same diameter (d) of 0.2 to 0.35 mm.

Abstract: A pneumatic vehicle tire has two beads each having a bead core and a carcass of at least one layer anchored at the bead cores within the beads. The beads further have bead profiling members. A reinforcement structure is located radially outwardly of the carcass, and a tread is positioned radially outwardly of the reinforcement structure. The carcass is made of aramid cord fabric and the bead cores are made of aramid cords. The reinforcement structure is made of synthetic fiber-reinforced rubber or of aramid cords. The bead profiling members are made of rubber reinforced with synthetic fibers.

Abstract: A belted radial ply tire which comprises a bead core disposed in each bead portion, a carcass extending between the bead portions and turned up around the bead cores, and a belt comprising at least two cross plies disposed radially outside the carcass and inside the tread, andin a state that the tire is mounted on its regular rim and inflated to its regular inner pressure but loaded with no tire load, the effective belt width BW of the effective belt part BE of the belt, the belt edge camber height CH of the belt, and the tire section width TW satisfy2.50(BW/TW)-1.25<CH<13.3(BW/TW)-4.65.

Abstract: A motorcycle radial tire which comprises a tread curved so that the maximum cross section width of the tire lies between the tread edges, a carcass having at least one ply of organic fiber cords extending between beads of the tire and turned up around bead cores disposed one in each bead, a belt disposed radially outside the carcass and comprising a breaker and a band, the breaker comprising a first ply disposed adjacently to the carcass and a second ply disposed on the radially outside of the first ply, the first and second breaker plies made of parallel cords inclined with respect to the tire equator so that the first ply cords cross the second ply cords, the edges of the first breaker ply folded back upon the second breaker ply so that a space is provided between the axially inner edges of the folded portions, the band disposed radially outside the breaker to extend over said space, the band comprising a ply of organic fiber cords wound spirally at an angle of not more than 5 degrees with respect to the ti

Abstract: A medium pneumatic truck tire (10), has a belt package (18) comprising a plurality of belt plies (20, 22, 24, 26). The tread (16) of the tire is 200 to 380 mm wide (8 inches to 15 inches). In the shoulder area (31) of the tire, an overlay strip (32) is abutted against belt edge (34) of top belt (26) and is disposed over belt edge (33) of the adjacent belt (24). The overlay strip (32) is applied in two layers, and the reinforcing cords (38) therein have an angle of about 0.degree. with respect to the equatorial plane of the tire (10). The overlay strip (32) is about 51 mm (2 inches) wide and has an overlap splice of about 40 mm (1.5 inches). The overlay strip (32) overlaps belt edge (36) by 15 to 20 mm (0.5 to 0.75 inch).

Abstract: A radial tire for motorcycle has a belt layer of cords with modulus of elasticity of 600 kg/mm.sup.2 or more wound spirally on a carcass nearly parallel to the tire equator, and a bead apex rubber disposed on a bead core between a carcass main portion extending from a tread to a bead core and a carcass turned up portion. The bead apex rubber consists of a soft apex part SA with JISA hardness of 50 to 60 degrees extending radially outward from the bead core, and a hard apex part HA with JISA hardness of 70 to 95 degrees extending radially outward from the soft apex part SA. A height h1 the soft apex part SA from a bead base is 0.20 to 0.40 times a height h0 of the tread end, and a height h2 of the hard apex part HA is 0.50 to 1.25 times the height h0 of the tread end.

Abstract: A reinforcement assemblage formed at least in part of continuous monofilaments of liquid crystal organic polymer or polymers, characterized by the following features:(a) the diameter D.sub.m of the monofilaments is at least equal to 40 .mu.m and less than 400 .mu.m;(b) the tenacity T.sub.a of the assemblage is greater than 80 cN/tex;(c) the secant tensile modulus M.sub.a of the assemblage is greater than 2000 cN/tex;(d) at least one of the monofilaments is practically wound helically around an axis, the acute angle .gamma. which each monofilament makes with this axis, which is assumed rectilinear, being less than 30.degree.;(e) the twist of each monofilament on itself is less than 10 turns per meter of assemblage.Articles reinforced by these assemblages, in particular automobile tires.

Abstract: A tire cord made of a multifilament yarn of polyvinyl alcohol having a degree of polymerization of at least 1500, the yarn having a tensile strength of at least 10 g/d and an index of hot water resistance of at least 50.

Abstract: A pneumatic tire, which comprises a tread portion (2) having a pair of tread edges, a pair of axially spaced bead portions (4), a pair of sidewall portions (3) extending between the tread edges and the bead portions (4), a bead core (5) disposed in each of the bead portions (4), a carcass (6) extending between the bead portions and turned up around the bead cores, a rubber tread disposed radially outside the crown portion of the carcass defining the tread portion, and a belt (7) made of at least one spirally wound belt cord (11) disposed between the carcass and the rubber tread, the belt cord (11) comprising a higher modulus strand (13A) and a lower modulus strand (14A) which are twisted together, the higher modulus strand (13A) made of at least one continuous organic filament (13) having a higher elastic modulus, the lower modulus strand (14A) made of at least one continuous organic filament (14) having a lower elastic modulus, and in a unit length of the belt cord, the length (L1) of the higher modulus fila

Abstract: A pneumatic radial tire in which a tread weight .alpha. per unit ground contact area is selected to be not greater than 1.80.times.10.sup.-3 kg/cm.sup.2, a cord reinforcing ply which extends up to a location outside of a top end of a bead filler in a radial direction of the tire is disposed in a bead portion and a cord angle .theta. of the cord reinforcing ply relative to a circumferential direction of the tire is selected to be 25.degree.-80.degree., a height RH of the cord reinforcing ply from a rim base up to the top end of the cord reinforcing ply, which is measured in the radial direction of the tire, is selected to satisfy the ratio, RH/SH=0.28-0.65, with SH being a cross-sectional height of the tire, and a height FH of the bead filler from the rim base up to the top end of the bead filler, which is measured in the radial direction of the tire, is selected to satisfy the ratio, FH/SH=0.11-0.28, with SH being the cross-sectional height of the tire.

Abstract: In order to improve the resistance of a crown reinforcement (20) of a radial tire to perforations, cuts and the drawbacks resulting therefrom, the crown reinforcement (20) is formed of three plies (21, 22, 23) of non-stretchable metal wires or cables. The resistances R.sub.1, R.sub.2, R.sub.3 of these plies being such that1.5.ltoreq.R.sub.1 /R.sub.2 .ltoreq.2.5and0.5.ltoreq.R.sub.3 /R.sub.2 .ltoreq.1.5,the two radially outer plies (22, 23) having wires or cables separated by a distance (e) equal to at least their diameter.

Abstract: A method of preparing a ply of composite material by applying an adhesive to a textile material comprising greige cords, so as to achieve an acceptable bond between the cords an elastomeric matrix, while not significantly altering the properties of the cords, is provided. The textile material comprises warp cords and weft cords; the weft cords are used to convey the warp cords through a heat setting oven without applying substantial tension to the warp cords, so as to not change their stress-strain properties. In the illustrated embodiment, the warp cords comprise aramid having a linear density of 500 to 3600 Denier and a twist multiplier of 5 to 8. The cords can be used in a crown reinforcing spirally wound overlay structure of a tire.

Abstract: A motorcycle tire which comprises a carcass (6) extending between tire bead portions (4), and a belt (7) disposed radially outside the carcass, wherein the belt (7) is formed by spirally winding at least two reinforcing members (11 and 12) having different elastic moduli so that the lower elastic modulus reinforcing member (11) and the higher elastic modulus reinforcing member (12) serially appear in the widthwise direction of the belt.

Abstract: A radial tire for motorcycles which comprises: a carcass ply of organic fiber cords arranged radially at an angle of 70 to 90 degrees to the tire equator and turned up around bead cores to form two turned up portions and a main portion therebetween; and a belt disposed radially outside the carcass and inside a tread, wherein the radial height Ht of the radially outer edge of each carcass turned up portion is 0.5 to 1.2 times the radial height of the tread edge, both from the bead base. The belt is composed of three pieces, two lateral pieces and a central piece therebetween, each piece being made of at least one spirally wound cord having an elastic modulus of not less than 600 kgf/sq.mm and formed by winding spirally a ribbon of rubber in which the at least one cord is embedded. The width of the central piece of the belt is 0.1 to 0.6 times the tread width. The central piece is differed from at least one of the lateral pieces in respect of cord specification and/or cord arrangement.

Abstract: A pneumatic radial tire for truck and bus comprises a carcass ply containing cords arranged substantially in a radial direction of the tire and a belt superimposed about said carcass ply and comprised of plural belt layers each containing steel cords arranged at a cord angle of 5.degree.-20.degree. with respect to an equator of the tire. In this case, the steel cord for the belt layer has a two-layer structure of a core comprised of two steel filaments and a single sheath comprised of 6-8 steel filaments and satisfies the particularly relationships on filament diameter, twisting pitch, bending rigidity, tensile strength and distance between adjoining cords.

Abstract: A belted radial tire has a belt composed of a breaker and a band, the breaker disposed radially outside a carcass and comprising at least two plies of cords inclined with respect to the tire equator so that the cords in each ply cross the cords in the next ply, the band disposed on the radially outside of the breaker and composed of a strip of rubberized parallel organic fiber cords which strip is wound spirally and continuously around the breaker from its one edge to the other edge, the number of the organic fiber cords in the strip being in the range of 10 to 25, the winding pitches of the strip changed in the axial direction of the tire so that the pitches are greater in a central region of the breaker than side regions, the pitches in the side regions being substantially a half of the strip width, and the pitches in the central region being not less than the strip width.

Abstract: A cut resistant pneumatic tire is provided. The tire has a monofilament wire structure embedded in or under its tread or sidewall, and is used in off the road applications such as mining. The monofilament wire has a diameter of 0.4 to 1.2 mm and is made of brass plated steel. The wire may be woven or may have a spring link configuration. Two monofilament wires may be twisted together, and when two such wires are used, the total diameter is 0.8 to 1.4 mm.

Abstract: A motorcycle radial tire includes a carcass having at least one ply of radially arranged organic fiber cords turned up around a pair of bead cores, the radial height (Ht) of the radially outer edge of the carcass turned up portions being more than 0.6 times and less than 1.2 times the radial height (Hs) of tread edges, a first belt having one cord or a plurality of parallel cords wound spirally so that the windings thereof are laid at small angles with respect to the tire equator, a second belt having one ply of parallel organic fiber cords laid at at angle of 10 to 30 degrees with respect to the tire equator, a bead apex made of rubber having a JIS(A) hardness of 65 to 75 disposed between the main portion and each turned up portion of the carcass, and the radial height (Ha) of the radially outer edge of the bead apex from the bead base line being more than 0.5 times and less than 1.2 times the radial height (Hs) of the tread edges.

Abstract: A pneumatic radial tire comprising a carcass and a belt comprising belt plies composed of steel belt cords wherein at least two circumferential grooves are constructed in the tread part continuously in the direction of the tire's equator, and lateral grooves in some parts defined by dividing the tread part in the direction of the tire's axis into approximately three. The tire prevents one-side drifting of a car in driving, improves a straight-forward driving performance.

Abstract: A pneumatic radial tire comprising a toroidal carcass layer having a number of radially extending cords buried therein, a belt layer arranged on a radially outer side of the carcass layer and containing a number of nonstretchable cords inclined to an equatorial plane of the tire, and a reinforcing layer arranged between the carcass layer and the belt layer and containing a number of reinforcing elements. The reinforcing elements extend in parallel to the tire equatorial plane as a whole, and are waved at a substantially equal wavelength. The phase of a plurality of the reinforcing elements among all the reinforcing elements buried in the reinforcing layer is different from that of the remaining reinforcing element or elements.

Abstract: A steering stability in a pair of pneumatic radial front and rear tires is considerably improved without sacrificing the tire durability by making a circumferential rigidity of an auxiliary belt in the front tire at a portion corresponding to a central zone of a belt in widthwise direction thereof larger than that of an auxiliary belt in a rear tire at the portion corresponding to the central zone of the belt in widthwise direction thereof.

Abstract: A radial tire with reduced running noise, which comprises a belt comprising two cross plies of cords laid an angle of 10 to 40 degrees with respect to the tire equator, and a pair of axially spaced narrow dampers disposed radially outside of the belt. Each damper has a width L of 0.1 to 0.36 times the width WBO of the outer belt ply. The dampers are centered on two points P, respectively, each point P being spaced apart from the tire equator towards each side of the tire equator by a distance H of 0.1 to 0.25 times the width WBO of the outer belt ply. The axially inner edge of each damper is spaced apart from the the tire equator by a distance D of 0.05 to 0.2 times the width WBO of the outer belt ply. Each damper is formed by spirally winding a cord so that the windings or turns are substantially in parallel to the tire equator.

Abstract: A pneumatic radial tire for a passenger car, which includes a plurality of grooves provided on the surface of a tread and extending at least in a tire circumferential direction and a belt having a double layer structure and provided within the tread, characterized in that the depth of the grooves is in the range of 6.0 to 8.5 mm, the thickness of a rubber under the groove defined as the distance from the bottom of the groove to the outermost belt layer is in the range of 0.5 to 2.5 mm, one of the belt layers comprises aramid fiber cords with the other belt layer comprising steel cords, and the total sectional area, .alpha., of steel wires per 50 mm width of the belt layer comprising steel cords is 5 to 14 mm.sup.2.

Abstract: Highly durable, lightweight tires of a pneumatic radial type for passenger cars are constructed with a tread portion having on its outer peripheral surface a plurality of grooves arranged circumferentially of the tire and a belt layer formed from an array of steel cords and disposed in the tread. Each of the steel cords results from twisting a selected number of steel filaments each of specified contents of C, Si and Ni and has a specified level of tensile strength. The distance of rubber from a bottom end of each of the grooves to an outer surface of the steel cord array is defined to be of a specified range as determined cross-sectionally of the tire.

Abstract: A method and apparatus for reducing the magnitude of a uniformity characteristic in a cured tire and the tire produced thereby. A signal is generated which is indicative of the magnitude of the uniformity characteristic. The signal is also indicative of the location on the tire to be corrected. At least a portion of one carcass reinforcing member of the tire is permanently deformed a predetermined amount at the location indicated by the signal to correct the uniformity characteristic.

Abstract: A pneumatic tire in which the steel belt ply or plies are enclosed in at least two wraps of a cap ply fabric which is wider than the steel belt ply and which is adhered to the belt ply as well as the tire cord outside of the belt ply.

Abstract: A pneumatic radial tire for a two-wheeled vehicle, including a carcass constituted by at least one carcass ply composed of cords extending at an angle of 75.degree. to 90.degree. with respect to an equatorial plane of the tire, and a belt constituted by at least two belt plies. The belt plies is arranged radially outwardly on an outer peripheral side of a crown portion of the carcass, and composed of cords extending substantially in a circumferential direction of the tire. The number of the cords per unit width of an outermost belt ply is in a range of 30% to 80% of that of a belt ply adjacent radially inwardly to the outermost belt ply as considered on the average over the entire width of the belt.

Abstract: A pneumatic radial tire comprising a carcass and a belt comprising belt plies composed of steel belt cords wherein at least two circumferential grooves are constructed in the tread part continuously in the direction of the tire's equator, and lateral grooves in some parts defined by dividing the tread part in the direction of the tire's axis into approximately three or four equal areas. The tire prevents one-side drifting of a car in driving, improves a straight-forward driving performance.

Abstract: A fiber-reinforced rubber article has a rubber body portion with a fiber reinforcement embedded therein. The fiber reinforcement includes a plurality of tubular braided cords braided by yarns. Each of the tubular braided cords is braided by more than three yarns at a braid angle in a range between 10.degree. and 35.degree., wherein said braid angle is an angle between a yarn of the tubular braided cord and the axial line of the tubular braided cord. Each tubular braided cord also has a fistulous center hole defined by the tubular braided cord.

Abstract: A pneumatic radial tire for a passenger car, which includes a plurality of grooves provided on the surface of a tread and extending at least in a tire circumferential direction and a belt layer having a double layer structure and provided within the tread, characterized in that the total sectional area, .alpha., of steel wires per 50 mm width of the belt layer is in a range satisfying 5.ltoreq..alpha..ltoreq.9 mm.sup.2, the depth, d, of the grooves is in a range satisfying 6.0.ltoreq.d.ltoreq.8.0 mm, and the thickness, t, of rubber under the grooves defined as the distance from the bottom of the groove to the outermost belt layer is in a range satisfying 1.0.ltoreq.t.ltoreq.2.5 mm.

Abstract: A pneumatic tire for motorcycles comprises a tread, a pair of sidewalls each toroidally extending from each side end of the tread, a carcass comprised of at least one cord ply arranged at a cord angle of 75.degree.90.degree. with respect to an equator of the tire, and a belt arranged between the tread and the carcass and comprised of at least two cord layers. In this tire, the belt is comprised of at least innermost cord layer located at a carcass side and at least one cord layer located at a tread side and comprised of a cord spirally wound in the circumferential direction of the tire so as to extend in the widthwise direction of the tire, in which a widthwise end of at least one cord layer located at the carcass side is located within a particular region to tread width and sidewall height.

Abstract: Pneumatic radial tires for automotive use are constructed with a belt layer reinforced with a steel cord of a unique structure. The steel cord results from the preformation of a single steel wire into a spiral shape meeting specified spiral parameters as determined by specified spiral diameters, specified wire diameters and specified spiral pitches. Significant weight saving is attainable with sufficient driving performance.

Abstract: A heavy-duty radial tire including a carcass and four steel cord belts bearing most of stress of the tire. The carcass and the belts cross each other. An outer side belt layer of two belt layers of different cord diameters which are defined by the belts being divided into the two belt layers, the outer side belt layer being a belt layer of the two belt layers which is disposed at an outer circumferential side of the tire in a radial direction thereof; and an inner side belt layer disposed further toward an inner circumferential side of the tire in the radial direction thereof than the outer side belt layer. A difference between belt cord angles of respective belts of the outer side belt layers is less than or equal to 5.degree.. A difference between belt cord angles of respective belts of the inner side belt layers is less than or equal to 5.degree.. Further, 1<.PHI. out/.PHI. in.ltoreq.2.5, and .alpha. in-.alpha. out.gtoreq.5.degree. and (.alpha. out+.alpha. in)/2.ltoreq.23.degree., wherein: .PHI.

Abstract: One or more plies of reinforced elastomer, particularly two plies (10),(12) of rubber reinforced with twisted filament metallic cords (14) and more particularly a tire belt made up of the two plies (10),(12) is disclosed having cords (14) of 2.times.0.30 HT construction with opposed 23.degree. angles to the direction of reinforcement of the belt.

Abstract: Metallic cord for reinforcing elastomeric articles and apparatus for making same including a round section and equal diameter filaments and a core (11) of two strands of two filaments (5,6,15,16) one strand being untwisted and the other strand having a twist and a first lay length so as to be twisted around the one strand.An outer layer (12) of filaments (21-28) twisted around the core (11) and having the same twist direction and a second lay length half of the core (11) lay length.

Abstract: A pneumatic tire with carbon fiber cord reinforcement wherein the carbon fiber cords have a round cross sectional shape and a twist per inch (TPI) of 1.2 to 1.6 turns per inch (TPI) is provided. Preferably, the carbon fiber cords are coated with an RFL or epoxy/RFL adhesive. It is also preferred that carbon fiber cords having an S twist and carbon fiber cords having a Z twist be used in the same reinforcing plies in the tire. Especially preferred is the incorporation of carbon fiber cords in a folded belt.

Abstract: Tires of a large size for use off-the-road with super tensile reinforcement having values of at least 4655N (1046 lbs) break strength for bunched type cord.

Abstract: A pneumatic radial tire for truck and bus comprises a carcass ply containing cords arranged substantially in a radial direction of the tire and a belt superimposed about said carcass ply and comprised of plural belt layers each containing steel cords arranged at a cord angle of 5.degree.-20.degree. with respect to an equator of the tire. In this case, the steel cord for the belt layer has a two-layer structure of a core comprised of two steel filaments and a single sheath comprised of 6-8 steel filaments and satisfies the particularly relationships on filament diameter, twisting pitch, bending rigidity, tensile strength and distance between adjoining cords.

Abstract: A steel cord for reinforcement of rubber products composed of two material wires of a diameter of 0.25 to 0.40 mm and a carbon content of 0.75 to 0.88 wt % which are entwisted at a twist pitch of 9.0 to 16.0 mm and in open structure, with improved fatigue resistance, flexibility and corrosion resistance.

Abstract: A pneumatic radial tire including one or more belt layers, wherein cords are used as cords for reinforcing at least one belt layer. These cords are formed by impregnating and attaching a resin having a modulus in tension of not more than 150 kg/mm.sup.2 to bundles of cord-like fibers composed of a number of filaments having a tensile strength of not less than 15 g/d and a fineness of 1-15 deniers, an impregnated and attached amount of the filaments being in a range of 30% to 70 wt % relative to a weight of the filaments, and each of the cords has an elliptical or rectangular cross-section shape having an aspect ratio of a major axis (b)/a minor axis (a) being 1.5 to 5. Each of the bundles of the fibers are not twisted.

Abstract: A steel cord includes a core layer composed of three wires, an intermediate layer composed of seven wires, and an outer layer 12 composed of 13 wires. The space ratio of the intermediate layer is in the range from 25% to 34%. and the space ratio of the outer layer is in the range from 10% to 20%. A tire is manufactured by using the steel cord.

Abstract: A high speed radial tire has a carcass and a belt layer, wherein; in the state of inflated with a standard internal pressure on a standard rim, a equator height H1 defined as a height of crossing point at which the inner surface of the belt layer intersects the surface of the tire equator is larger than an outer end height H2 defined as a height of the outermost end of the inner surface of the belt layer. Furthermore, a belt camber quantity H defined as a difference between the height H1 and the height H2 is set at 6% or more of the belt width W.

Abstract: A pneumatic tire includes a toroidal carcass anchored by at least a pair of bead cores and a belt having strips. The strip has as reinforcing elements a plurality of zigzag or wave-shaped cords or filaments arranged side by side around a crown of the toroidal carcass. The strip is coated with a high molecular weight material less in modulus of elasticity than the reinforcing elements. Waves of the reinforcing elements of the strips are arranged in width directions of the belt so that ratios of amplitudes to wave lengths of the waves are maximum at side edges of the belt. The ratios are preferably progressively increased toward the side edges of the belt. Ratios of amplitudes to pitches of the waves are 0.005-0.175 and ratios of pitches of the waves to maximum circumferential lengths when filled with a normal inner pressure is less than 0.025.

Abstract: An off-the-road pneumatic steel radial tire comprises a radial carcass comprised of at least one carcass ply containing steel cords and a belt superimposed about a crown portion of the carcass and comprised of at least three laminated steel cord layers. In this tire, the belt includes at least two main belt layers each containing substantially inextensible steel cords, in which steel cords included in at least one of these main belt layers satisfy conditions that a cord diameter is. the same in this layer but different from that of the remaining main belt layer, and a ratio of cord diameter in these main belt layers is within a range of 1.2-3.0, and a ratio of total breaking load of cords in these main belt layers per unit width is within a range of 1.1-2.0 times.

Abstract: A pneumatic radial tire comprises a belt comprised of plural belt layers, in which at least one belt layer is formed by arranging particular twisted cords, which are obtained by twisting particular filament-resin composite bodies, at a particular end count. In this tire, the weight is light, the rolling resistance and steering stability as well as the resistances to bending of belt cord in the rapid turning and breaking of belt cord in the running on bad road are considerably excellent.

Abstract: A pneumatic radial tire is disclosed, including an annular tread having a belt incorporated therein, a pair of sidewalls which extend radially inward from both ends of the annular tread and a bead portion, provided at the inner end of each sidewall, wherein the belt includes a belt ply having a plurality of belt cords in parallel arrangement, the belt cords being formed by twisting a plurality of steel filaments or two or more strands each consisting of a plurality of steel. filaments, and at least one of said steel filaments being replaced by a filament of a shape-memory alloy which, before it is twisted either as a belt cord or as a strand which forms a belt cord, has been heat set at a predetermined heat set temperature whereby the filament has a linear shape at a temperature below the heat set temperature and has a wavy shape at a temperature at or above the heat set temperature.