A reinforcement strand (400) comprises a core (403) around which steel filaments (404) are twisted all with the same final lay length and direction. The steel filaments are arranged in an intermediate layer comprising N first steel filaments and an outer layer of 2N steel filaments circumferentially arranged around the intermediate layer. In the intermediate layer filaments will contact one another at a closing lay length that is determined by the number of steel filaments N in the intermediate layer, the diameter of the core and the diameter of the first steel filaments. By choosing the final lay length and direction equal to the between two and six times the closing lay length gaps will form between the intermediate layer filaments. The 2N outer layer filaments are further divided into a group of smaller (408) and a group of larger (406) diameter steel filaments.

This steel cord for reinforcing a rubber article includes one core strand having a two-layer twisted layer structure formed by intertwining a plurality of steel filaments, and a plurality of sheath strands having a twisted layer structure formed by intertwining a plurality of steel filaments. The sheath strands are intertwined around the core strand, a core of the core strand is formed by two core filaments, and the diameter of outermost layer sheath filaments forming an outermost layer sheath of each sheath strand is greater than the diameter of filaments inside the outermost layer sheath of the sheath strand.

Elevator coated ropes or belts are disclosed. The coated rope or belt may include at least one cord and a jacket retaining the at least one cord. The cord may include a plurality of filaments. The filaments are free of second-order helical structure. In a first embodiment, the filaments includes at least one inner filament and a plurality of outer filaments surrounding the at least one inner filament. The outer filaments are bunched together by forming a first-order helical structure through the length of the cord. In a second general embodiment, the filaments are free of both first- and second-order helical structures. The filaments are bunched together by a restraining loop or adhesive at one or more locations along the length of the cord. Methods of making the tension cord are also disclosed.

The method allows the manufacture of at least first and second assemblies (26, 28) of M1 filamentary elements and M2 filamentary elements, at least one of the first and second assemblies (26, 28) comprising several filamentary elements (14) wound together in a helix.

The method comprises a step of assembling M filamentary elements (14) together into a layer of the M filamentary elements (14) around a temporary core (16) to form a temporary assembly (22), and a step of splitting the temporary assembly (22) into at least the first and second assemblies (26, 28) of M1 filamentary elements and M2 filamentary elements.

Provided is an elastomer reinforcement cord with improved rust inhibition. An elastomer reinforcement cord (10) includes metal filaments and a polymer material. The elastomer reinforcement cord (10) has a multi-strand structure which includes: at least one core strand (21) formed by twisting plural metal filaments (1a) and (1b) together; and two or more sheath strands (22) each formed by twisting plural metal filaments (11a) and (11b) together, and in which the sheath strands are twisted together around the core strand. In a region surrounded by a line connecting the centers of the metal filaments constituting the outermost sheath layer of the core strand at a cross-section in a direction orthogonal to an axial direction after vulcanization of the core strand, when a region occupied by other than the metal filaments is defined as a gap region, a filling rate, which is a ratio of the area of the polymer material with respect to the gap region, is 52% to 120%.

Provided is an elastomer reinforcement cord in which the problem of stress concentration at an interface between an elastomer and a metal cord is solved and the durability is thereby improved. The elastomer reinforcement cord includes metal filaments (1a) and (1b), and a polymer material (3) having a melting point or softening point of 80° C. to 160° C. The elastomer reinforcement cord has a core (11) and at least one sheath layer (12). In a region surrounded by a line connecting the centers of the metal filaments constituting the outermost sheath layer at a cross-section in a direction orthogonal to an axial direction after vulcanization, when a region occupied by other than the metal filaments is defined as a gap region, the polymer material is contained in this gap region, and a filling rate, which is a ratio of the area of the polymer material, is higher than 120%, taking the area of the gap region as 100%.

Provided is an elastomer reinforcement cord with improved rust resistance. An elastomer reinforcement cord 10 includes metal filaments and a polymer material. The elastomer reinforcement cord 10 has a multi-strand structure which includes: at least one core strand 21 formed by twisting plural metal filaments 1a and 1b together; and two or more sheath strands 22 each formed by twisting plural metal filaments 11a and 11b together, the sheath strands being twisted together around the core strand. An intra-sheath-strand filling rate a, which is a ratio of the area of the polymer material with respect to an intra-sheath-strand gap region A, is 52% or higher, and an inter-strand filling rate b, which is a ratio of the area of the polymer material with respect to an inter-strand gap region B, is 75% or higher.

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≤175, 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(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′, 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 is the helix angle of each intermediate thread (F2) and γ and γ′ are the helix angle of each external thread (F3, F2′).

A steel cord containing a core layer and an sheath layer, the core layer containing a plurality of core wires with a number of n and the sheath layer comprises a plurality of sheath wires with a number of m, and the steel cord has a flat cross-section with a major axis and a minor axis, the flat cross-section has a flat ratio being the ratio of the length of the major axis and the length of the minor axis, the flat ratio is more than 1.2, the steel cord has a breaking load being BL.sub.cord, the core wires and the sheath wires have a sum breaking load being Sum BL.sub.wires when the core wires and the sheath wires are un-twisted from the steel cord, BL.sub.cord and Sum BL.sub.wires satisfies the following formula: BL.sub.cord/Sum BL.sub.wires>96%. The steel cord has higher breaking load.

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.