WIRE DRAWING OF OPTICAL FIBER AND APPARATUS THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a wire drawing method of an optical fiber preventing increase in loss percentage according to the wire drawing and increasing efficiency of the wire drawing of the optical fiber by using an optical fiber base material even having a large diameter. SOLUTION: Whole of an optical fiber base material 1 having a large diameter is fused in a first heating furnace 7 and drawn to an optical fiber base material 2 having a thin diameter, then fused in a second heating furnace 11 and subjected to a wire drawing to obtain an optical fiber 3. A drawing force to draw the thinned optical fiber base material and a feeding force to the second heating furnace are applied to the thinned optical fiber base material with keeping the base material to the second heating furnace by pulling means 5 provided in the vicinity of upside of the second heating furnace. The wire drawing of the optical fiber is finished in a state of keeping a dummy bar 1a at a top end of the thinned optical fiber base material after the finish of the drawing and only a residual part 2a can be a lost amount. Positions of whole the first heating furnace and the pulling means are horizontally adjusted to the first heating furnace by a drawing feeding means 10 while the whole is fed at a prescribed feeding speed to the first heating furnace corresponding to the wire drawing.