A cord (50) comprises: an internal strand (TI) comprising internal layer (C1) of Q=1 internal wire (F1), an intermediate layer (C2) of M intermediate wires (F2) wound around the internal layer (C1) with a pitch p2, an external layer (C3) of N external wires (F3) wound around the intermediate layer (C2) with a pitch p3; and L>1 external strands (TE) comprising an internal layer (C1′), an external layer (C3′). The external layer (CE) of the cord is wound around the internal layer (CI) of the cord in a direction of winding of the cord (50). Each external layer (C3, C3′) of each internal and external strand (TI, TE) is wound in the same direction of winding that is the opposite to the direction of winding of the cord (50). The external layer (CE) of the cord (50) is desaturated, and 0.36≤(p3−p2)/p3≤0.57.

A cord (50) comprises: an internal strand (TI) comprising an internal layer (C1), and an external layer (C3); and L>1 external strands (TE) comprising an internal layer (C1′) of Q′=1 internal wire (F1′), an intermediate layer (C2′) of M′ intermediate wires (F2′) wound around the internal layer (C1′) with a pitch p2′, and an external layer (C3′) of N′ external wires (F3′) wound around the intermediate layer (C2′) with a pitch p3′. The external layer (CE) of the cord is wound around the internal layer (CI) of the cord in a direction of winding of the cord (50). Each external layer (C3, C3′) of each internal and external strand (TI, TE) is wound in the same direction of winding that is the opposite to the direction of winding of the cord (50). The external layer (CE) of the cord (50) is desaturated, and 0.36≤(p3′−p2′)/p3′≤0.57.

Provided is a steel cord for rubber article reinforcement, which has both the tensile strength in the cord axial direction and the strength in the shear direction at higher levels. A steel cord (10) for rubber article reinforcement includes: a single core strand (11) having a layer-twisted structure; and plural sheath strands (12) each having a layer-twisted structure, and the sheath strands (12) are twisted around the core strand (11). In the sheath strands (12), a ratio between the diameter of a core filament (12a) and the diameter of a sheath filament (12b) is 0.75 to 0.85, and a ratio between the strength of the core filament (12a) and the strength of the sheath filament (12b) is 0.55 to 0.7.

A belt containing steel cords, the steel cords containing strands made of steel filaments wherein the largest diameter filaments are at least intermittently positioned at the radially outer side of the steel cord. Such a configuration can be obtained by using steel cord constructions wherein the thickest filaments are positioned outside of the steel cord which is contrary to the current practice. In a further embodiment the largest diameter filaments fill up some or all of the valleys of the strands at their radially outer side. These monofilaments thus have the same lay length and direction as the strands in the steel cord. The advantage of putting the largest filaments at the outside is that they will break first and thus will be readily detectable by electrical, magnetic or visual means. In this way a belt is provided that can be monitored easier and more conveniently than prior art belts.

The invention relates to a multi-strand cord (50) comprising an internal layer (CI) of the cord made up of K=1 three-layer (C1, C2, C3) internal strand (TI), with the internal layer (C1) being made up of Q internal metallic threads (F1), the intermediate layer (C2) being made up of M intermediate metallic threads (F2) and the external layer (C3) being made up of N external metallic threads (F3), and an external layer (CE) of the cord made up of L>1 three-layer (C1′, C2′, C3′) external strands (TE) wound around the internal layer (CI) of the cord, with the internal layer (C1′) being made up of Q′ internal metallic threads (F1′), the intermediate layer (C2′) being made up of M′ intermediate metallic threads (F2′) and the external layer (C3′) being made up of N′ external metallic threads (F3′).

The cord (50) has: an endurance criterion SL≤40 000 MPa.Math.mm with

[00001]$SL=\max \left(\frac{\Delta {\sigma }_{\mathrm{bending}\_\mathrm{CI}}}{\mathrm{Cp}};\frac{\Delta {\sigma }_{\mathrm{bending}\_\mathrm{CE}}}{C_r\times \mathrm{Cp}}\right);$  and a size criterion Ec≥0.46 with Ec=Sc/Se.

A steel cord for the reinforcement of elastomer products such as elevator belts, conveyor belts, synchronous or timing belts or hoses or tyres is presented. The steel cord comprises strands and monofilaments made of steel filaments. The strands themselves are also made of steel filaments twisted together. The strands form the outer layer of the steel cord. The monofilaments are twisted into the cord with the same lay length and direction as the strands and are positioned in the valleys between the strands on the radial outer side of the steel cord. The steel cord has the advantage that it has a better fill factor and a rounder aspect. Furthermore the monofilaments may act as an early wear indicator of the elastomer product.

Provided is a steel cord for reinforcing a rubber article which can further improve cut resistance when applied to a tire while maintaining the amount of steel to be used. A steel cord for reinforcing a rubber article comprising: one core strand 11 having a two-layered layered-twisted structure formed by twisting a plurality of steel filaments 1; and a plurality of sheath strands 12 having a layered-twisted structure formed by twisting a plurality of steel filaments 2, wherein the sheath strands are twisted around the core strand. A ratio dc/ds of a diameter dc of a sheath filament constituting the sheath of the core strand to a diameter ds of an outermost layer sheath filament constituting the outermost layer sheath of the sheath strand is more than 1.25 and not more than 1.50.

Provided is a steel cord for reinforcing a rubber article which can further improve cut resistance when applied to a tire. Provided is a steel cord for reinforcing a rubber article including: one core strand 11 having a layered-twisted structure formed by twisting a plurality of steel filaments 1; and a plurality of sheath strands 12 having a layered-twisted structure formed by twisting a plurality of steel filaments 2, wherein the sheath strands are twisted around the core strand. A ratio S1/S of the sum S1 of cross-sectional areas of outermost layer sheath filaments constituting an outermost layer sheath of the core strand to the sum S of cross-sectional areas of all filaments constituting the core strand is from 0.69 to 0.74, and a ratio Ps/P of the sum Ps of strengths of the sheath strands to strength P of the cord as a whole is from 0.81 to 0.85.

Provided is a steel cord for rubber article reinforcement, which has both the tensile strength in the cord axial direction and the strength in the shear direction at higher levels. A steel cord (10) for rubber article reinforcement includes: a single core strand (11) having a layer-twisted structure; and plural sheath strands (12) each having a layer-twisted structure, and the sheath strands (12) are twisted around the core strand (11). In the sheath strands (12), a ratio between the diameter of a core filament (12a) and the diameter of a sheath filament (12b) is 0.75 to 0.85, and a ratio between the strength of the core filament (12a) and the strength of the sheath filament (12b) is 0.55 to 0.7.

A belt containing steel cords, the steel cords containing strands made of steel filaments wherein the largest diameter filaments are at least intermittently positioned at the radially outer side of the steel cord. Such a configuration can be obtained by using steel cord constructions wherein the thickest filaments are positioned outside of the steel cord which is contrary to the current practice. In a further embodiment the largest diameter filaments fill up some or all of the valleys of the strands at their radially outer side. These monofilaments thus have the same lay length and direction as the strands in the steel cord. The advantage of putting the largest filaments at the outside is that they will break first and thus will be readily detectable by electrical, magnetic or visual means. In this way a belt is provided that can be monitored easier and more conveniently than prior art belts.