| 摘要 |
PURPOSE:To enable cooling and solidification after correction between forming rolls even if the arrangement of a fiber strand is disturbed in the nipple of a cross head die by passing a core between the cooled rolls before a tube consisting of a molten resin solidifies. CONSTITUTION:There is no need for making the clearance between the inside wall of a nipple 2 and an optical fiber strand 3 small, and a hollow type core A is passed through a forming roll device 6 before it is cooled to solidify in the stage of manufacturing said core by a cross head die 1. The device 6 has two forming rolls 8a, 8b and one guide roll 9 in a box-shaped housing 7 and cooling water 10 in a horizontally provided bottom part. The lower parts of the rolls 8a, 8b having the surfaces plates with Ni are held dipped in the water. Both sides of the core A are lightly pressed when the core passes under the top surface 8b of the roll 8a and a tube 5 is brought into contact with the roll surface and is further submerged in the water 10, by which the tube is cooled and is solidified without disturbance in the arrangement. |
