OPEN STEEL CORD STRUCTURE

摘要

A steel cord (114) for the reinforcement of rubber products comprises streng th elements (100, 132) and has length, a longitudinal central axis (112) and a cord pitch. Each of the elements (100) has a portio n on a plane YZ perpendicular to the longitudinal centra l axis (112). At least one of these projections takes the form of a curve with a radius of curvature which alternates between a maximu m and minimum. The curve further has a center of curvature. The radius of curvatur e and the center of curvature lie inside the curve so th at a convex curve is obtained. The cord (114) is further characterized by one or both of the following features: (i) the distance between two minimum radii of curvature of said curve measured along the longitudinal cen tral axis (112) is different from half the cord pitch; o r (ii) if all of said elements (100) provide a convex curve, at least one of said conv ex curves substantially differs from another convex curv e. The steel cord (114) allows full rubber penetration despite low values of cord d iameter and part load elongation (PLE).