Patent ID: 8474235

Claim:
A method of manufacturing a metal cord with three concentric layers of M+N+P construction, comprising a first, internal, layer having M wires of diameter d 1 , M varying from 1 to 4, around which there are wound together in a helix, at a pitch p 2 , in a second, intermediate, layer, N wires of diameter d 2 ′ N varying from 3 to 12, around which there are wound together as a helix at a pitch p 3 , in a third, outer, layer, P wires of diameter d 3 , P varying from 8 to 20, the method comprising the following steps which are performed in line: an assembling step by twisting the N wires around the first layer in order to form, at a point named the “assembling point”, an intermediate cord named “core strand” of M+N construction; downstream of the assembling point, a sheathing step in which the M+N core strand is sheathed with a rubber composition named “filling rubber”, in an uncrosslinked state; an assembling step in which the P wires of the third layer are twisted around the core strand thus sheathed; and a final twist-balancing step.