| 摘要 |
PURPOSE:To obtain the titled thick-walled optical glass fiber having excellent resistance to stress by making the delivery velocity of an overclad pipe to a heating part lower than the delivery velocity of an optical glass rod for a core and an optical glass pipe for a clad. CONSTITUTION:An optical rod 1 for a core and an optical glass pipe 2 for a clad are fixed to the first and the second chuck arm 15a and 15b of a carrier which is screwed to a feed driving shaft 13 which is rotated by the motor 11 of the first feeder 10 and a belt 12. Meanwhile, the overclad pipe 3 is fixed to the chuck arm 25a of a carrier 25 which is screwed to a feed driving shaft 23 which is rotated by the motor 21 of the second feeder 20 and a belt 22. The descending speed V2 of the carrier 25 is set against the descending speed V1 of the carrier 15 so that the relation, V2=(3/8)V2, is satisfied. The rod 1 and the pipe 2 are fed into a heating furnace 3 at the speed of V1, and the pipe 3 is fed at the speed of V2. |
