METHOD AND APPARATUS FOR PRODUCING OPTICAL FIBER

摘要

PURPOSE:To produce an optical fiber at a high linear velocity by efficiently and economically cooling a fiber obtd. by drawing. CONSTITUTION:When a fiber 2 obtd. by drawing under heating is cooled by passing through a fiber cooling tube 4 and the cooled fiber is coated with resin to produce an optical fiber 7, gaseous helium is fed into the fiber cooling tube 4 and circulated. The gaseous helium discharged from the tube 4 is purified with a helium purifier 11, mixed with pure gaseous helium and fed again into the tube 4.