METHOD AND APPARATUS FOR SEALING THE TOP OF A FURNACE FOR DRAWING OPTICAL FIBRE FROM A PREFORM

摘要

An apparatus and method for sealing the top (preform entry end) of an optical waveguide fiber draw furnace is disclosed. The apparatus includes an assembly (10) constructed and arranged to removably cover the top of the draw furnace (60) while mating with the downfeed handle (28). The apparatus includes an elongated sleeve (12) having a base (16) and a sealing mechanism (18) positioned on the sleeve at a location remote from the base. The sleeve (12) defines a chamber (50) for receiving the downfeed handle (28), and the sealing mechanism (18) is arranged with respect to the sleeve to mate with the downfeed handle received in the chamber. In one aspect of the invention, the apparatus further includes an inert gas purge (22, 24, 26) for providing an inert atmosphere within the chamber (50). A method of sealing the top of an optical waveguide fiber draw furnace is also disclosed.