摘要 |
A cord comprising at least a first pair and a second pair of wires (2a, 2b) of different diameter randomly disposed in the transverse section thereof, is obtained by arranging in the nacelle (7) of a double-twisting laying machine, a twister (16) operating upstream of a preformer (15). The twister (16), rotating in a direction opposite to that of the impeller (5) and at a speed which is twice that of the impeller, neutralizes the internal torsional stresses induced in the wires (2a, 2b) by effect of the double twisting carried out upon the action of the impeller itself. Thus, a better control of the preforming operation executed on the wires (2a, 2b) disposed parallelly in respectively coplanar axes is enabled. The obtained cord (1), within each laying pitch and only under a traction condition involving a load not exceeding 5 kg, has at least one right section in which at least one wire (2a, 2b) is spaced apart from at least one of the adjacent wires so as to facilitate the rubberizing step, by enabling access of the blend to the section and penetration of same along the cord (1) axis. The cord is preferably used as a reinforcing element in belt structures for tyres. <IMAGE> |