The subject of the invention is a cord (50) comprising a single layer (52) of helically wound metal filamentary elements (54). The metal filamentary elements define an internal enclosure (58) of the cord of diameter Dv. Each metal filamentary element (54) has a diameter Df and a helix radius of curvature Rf.

With Dv, Df and Rf being expressed in millimetres, the cord satisfies the following relationships:

9≤Rf/Df≤30, and

1.30≤Dv/Df≤2.10.

Pneumatic vehicle tire of radial type of construction, in particular a commercial vehicle tire, having a belt assembly (3) made up of at least three plies (8, 9, 10), namely two working plies (8, 9) and a protective ply (10) arranged radially on the outside with respect to the working plies (8, 9), wherein the protective ply (10) has reinforcing members (11) made up of one or more twisted-together steel filaments (12), wherein the steel of the steel filaments (12) of the reinforcing members (11) of the protective ply (10) can be assigned to the strength class ST or to a higher strength class, wherein the strength class ST has a tensile strength in MPa of 3980-2000 d and the strength class UT has a tensile strength in MPa of 4400-2000 d, wherein d is the diameter of a steel filament in mm.

A construction vehicle tire includes a carcass layer and a belt layer formed by six belts at an outer side of the carcass layer in a tire radial direction. A fourth belt arranged fourth from the carcass layer toward the outer side in the tire radial direction among the belt layer includes steel cords arranged along a predetermined direction. The steel cord includes one core strand having a two-layer-twisted structure in which a plurality of core filaments and a sheath filament forming a sheath are twisted, and a plurality of sheath strand twisted with the core strand, the sheath strand having a layer-twisted structure in which a plurality of steel filaments are twisted. A gap between the filaments is filled with a predetermined rubber material.

A two-layer multi-strand cord (60) comprises an internal layer (CI) of the cord made up of J>1 internal strands (TI) and an external layer (CE) of the cord made up of L>1 external strands (TE). The cord satisfies the relationship 95≤MC≤180, where MC=(J×MI+L×ME)/(J+L); MI=200×cos.sup.4(α)×[Q×(D1/2).sup.2×cos.sup.4(β)+P×(D2/2).sup.2×cos.sup.4(δ)+N×(D3/2).sup.2×cos.sup.4(γ)]/[Q×(D1/2).sup.2+P×(D2/2).sup.2+N×(D3/2).sup.2]; and ME=200×cos.sup.4(α′)×[Q′×(D1′/2).sup.2×cos.sup.4(ββ)+P′×(D2′/2).sup.2×cos.sup.4(δ′)+N′×(D3′/2).sup.2×cos.sup.4(γ′)]/[Q′×(D1′/2).sup.2+P′×(D2/2).sup.2+N′×(D3′/2).sup.2], where D1, D1′, D2, D2′, D3 and D3′ are in mm, α and α′ are the helix angle of each internal and external strand (TI), β and β′ are the helix angle of each internal thread (F1, F1′), δ and δ′ are the helix angle of each intermediate thread (F2, F2′) and γ and γ′ are the helix angle of each external thread (F3, F3′).

A two-layer multi-strand cord (60) comprises an internal layer (CI) of the cord made up of J>1 internal strands (TI) and an external layer (CE) of the cord made up of L>1 external strands (TE). The cord satisfies the relationship 100≤MC≤175, where MC=(J×MI+L×ME)/(J+L); MI=200×cos.sup.4(α)×[Q×(D1/2).sup.2×cos.sup.4(β)+N×(D2/2).sup.2×cos.sup.4(γ)]/[Q×(D1/2).sup.2+N×(D2/2).sup.2]; and ME=200×cos.sup.4(α′)×[Q′×(D1′/2).sup.2×cos.sup.4(β′)+N′×(D2′/2).sup.2×cos.sup.4(γ′)]/[Q′×(D1′/2).sup.2+N′×(D2′/2).sup.2], where D1, D1′, D2, D2′ are in mm, α and α′ are the helix angle of each internal and external strand (TI), β and β′ are the helix angle of each internal thread (F1, F1′), and γ and γ′ are the helix angle of each external thread (F2, F2′).

A steel cord for rubber reinforcement comprises a first group of core filaments (105) having a number of m and a second group of sheath filaments (110) having a number of n, m is three or four, the core filaments (105) are forming a helix, the core filaments (105) are not twisted together and being substantially parallel or the core filaments (105) have a twist pitch being more than 300 mm; the second group and the first group are twisted with each other, and the sheath filaments (110) are forming a flattened helix in the same direction of the helix of the core filaments (105), and the sheath filaments (110) have a cord twist pitch, at any cross-section of the steel cord, at least one interstice between two adjacent core filaments (105) is present. The steel cord has improved abrasion resistance and can contribute to the reduction of the weight of the tire.

A tire includes a tread and a crown reinforcement arranged radially internal to the tread. The crown reinforcement includes a protective reinforcement and a working reinforcement. The protective reinforcement includes a protective ply that exhibits a force at break greater than or equal to 1300 daN.Math.cm.sup.1. The protective ply includes protective reinforcing elements, each of which exhibits a force at break greater than or equal to 3000 N. The working reinforcement is arranged radially internal to the protective reinforcement and includes a working ply. The working ply includes working reinforcing elements, each of which includes a working cord formed of at least a strand that includes an external layer of unsaturated threads.

A two-layer multi-strand cord (60) has a modulus EC such that 50 GPaEC160 GPa. The cord comprises: (a) an internal layer (CI) of the cord made up of J>1 internal strands (TI) wound in a helix having a modulus EI, each internal strand (TI) comprising: an internal layer (C1) made up of Q1 internal threads (F1), and an external layer (C2) made up of N>1 external threads (F2) wound around the internal layer (C1), and (b) an external layer (CE) of the cord made up of L>1 external strands (TE) wound around the internal layer (CI) of the cord, each external strand (TE) comprising: an internal layer (C1) made up of Q1 internal threads (F1), and an external layer (C2) made up of N>1 external threads (F2) wound around the internal layer (C1).

A two-layer multi-strand cord (60) comprises an internal layer (CI) of the cord made up of J>1 internal strands (TI) and an external layer (CE) of the cord made up of L>1 external strands (TE). The cord satisfies the relationship 95MC175, where MC=(JMI+LME)/(J+L); MI=200cos.sup.4()[Q(D1/2).sup.2cos.sup.4()+P(D2/2).sup.2cos.sup.4()+N(D3/2).sup.2cos.sup.4()]/[Q(D1/2).sup.2+P(D2/2).sup.2+N(D3/2).sup.2]; and ME=200cos.sup.4()[Q(D1/2).sup.2cos.sup.4()+N(D2/2).sup.2cos.sup.4()]/[Q(D1/2).sup.2+N(D2/2).sup.2], where D1, D1, D2, D2, and D3 are in mm, and are the helix angle of each internal and external strand (TI), and are the helix angle of each internal thread (F1, F1), is the helix angle of each intermediate thread (F2) and and are the helix angle of each external thread (F3, F2).

Provided is an elastomer reinforcement cord which takes advantage of characteristics of a composite cord using steel filaments and a resin filament and in which a diameter (a geometrically calculated value) of the cord including only the steel filaments without resin, as calculated from a wire diameter of the steel filaments used, is substantially the same as an actual cord diameter after vulcanization. In an elastomer reinforcement cord 10 including a core and at least one sheath layer, in which metal filaments 2 and 3 and a resin filament 1 are twisted together, gaps between the metal filaments are filled with resin. The diameter of the cord is from 98 to 100.5% of the geometrically calculated value of the diameter of the cord including only the metal filaments, and a total length of gaps between the metal filaments forming an outermost sheath layer before vulcanization is 85% or less of the geometrically calculated value. In a region surrounded by connecting the center of each metal filament forming the outermost sheath layer on a cross section in a direction orthogonal to an axial direction of the cord, the ratio of a polymer material to a region other than the region occupied by the metal filaments is from 52 to 120%.