摘要 |
<p>A steel cord comprises a central bundle of three twisted steel filaments (1) with a diameter d1 and nine steel filaments twisted around said central bundle with the same twist pitch and twist direction as the central bundle. Three filaments (2) of said nine steel filaments have a diameter d2 and contact two adjacent steel filaments of the central bundle. Six steel filaments (3) of said nine steel filaments have a diameter d3 and contact both one steel filament of the central bundle and one steel filament of the three filaments with diameter d2. The ratio d2/d1 is greater than 1.05 and smaller than 1.16. The ratio d3/d1 is greater than - 0.205 + 0.814 x d2/d1 and smaller than - 0.105 + 0.814 x d2/d1.</p> |