METHOD AND APPARATUS FOR DRAWING OPTICAL FIBER

摘要

PROBLEM TO BE SOLVED: To provide a method and an apparatus for drawing an optical fiber, in which the volume change occupied by gas in the inside of a furnace body can be suppressed and by which a high quality optical fiber free from the diameter fluctuation can be drawn. SOLUTION: A gas feeding unit 17 for blowing out a seal gas toward the inner peripheral side is provided at an upper inlet of a drawing furnace 11. A closing member 31 which is formed to have an outer diameter nearly equal to that of the optical fiber preform 21 and hung from an engaging member 32 arranged at the upper part than the optical fiber preform 21 is arranged at the diameter reduced part 21b of the optical fiber preform 21 sent into the inside of the drawing furnace 11 at least after the diameter reduced part 21b comprising a shoulder part at the upper end of the optical fiber preform 21 has arrived at the upper inlet of the drawing furnace 11. COPYRIGHT: (C)2004,JPO