ELECTRIC CABLE OF LOW WIND NOISE AND LOW AUDIBLE NOISE (AN)

PURPOSE:To obtain an electric cable excellent in wind noise and AN characteristics by composing the outermost strand layer of thick and thin strands having nearly sectorial sections, forming a groove part at nearly the central position on the surface of each large diametral step and specifying their characteristics and shapes. CONSTITUTION:The outermost strand layer of a stranded wire is composed of thick strands 1 and thin strands 2 both having nearly sectorial sections and smooth step surfaces are spirally formed on the peripheral surface of the stranded wire by the difference between strands 1, 2, and also a groove part 11 is formed at nearly the central position on the surface of each large diametral step. Hereupon, where a center angle being formed with actual surfaces of each surface 10a of the large diametral step is thetae, an uneven level difference is h, an equivalent outside diameter of a surface- smooth electric cable to an ordinary electric cable is de, an outside diameter of the ordinary electric cable is d, a depth of a recess being formed between the strands adjoining each other which form a surface 10b of a small diametral step is delta and an opening width of the recess is t, expressions I to VI are satisfied. In this way, the electric cable of low wind noise and low AN having a constitution for attaining the optimum condition in both low wind noise and AN properties can be obtained.