| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an abnormal tension predicting cable capable of predicting abnormal tension when applied to the cable. SOLUTION: A mark is put on the surface of a cable sheath by means of a shape-memory material, and a shape stored precedently in a mark material presents itself in case of the application of the abnormal tension to the cable for the purpose of allowing the application of the abnormal tension to be recognized by visual observation and enabling a dangerous phenomenon such as rupture of a conductor and the like to be predicted. The shape-memory material for forming the mark is composed of a shape-memory plastic wherein a polymer having shape-memory properties is mixed into a thermoplastics material, and the mark is desirably put on the cable sheath by extrusion molding. The mark is linearly put in the longitudinal direction of the cable, and a nonlinear shape, for example, a wavy pattern is preferably stored in the shape-memory plastic for the mark by means of tension memory equal to or below an allowable tension.</p> |
