| 摘要 |
PURPOSE:To increase the restitutive force of an optical fiber bundle curl cord which is formed spirally around a mandrel so that the contraction speed after drawing is high by detaching the optical fiber bundle curl code from the mandrel and then winding it back in the opposite direction. CONSTITUTION:The cord 16 formed by covering an optical fiber bundle 11 of numbers of optical fibers with a plastic sheath 13 is wound around the mandrel 17, and heat-treated and then cooled; and the spiral curl cord 18 is detached from the mandrel 17. One end of the curl cord 18 manufactued as mentioned above is fixed and the other end is fitted to a rotatable jig, which rotates in the opposite direction of the winding direction to wind the cord back in the opposite direction, thus obtaining a curl cord 19. This curl cord 19 is increased greatly in the contracting speed after drawing and returns to its original length in a short time. |
