Method and apparatus for contaminant removal in manufacturing optical fibre
AssigneeStc PLC
InventorsIan D. Harding, Peter R. Ince, Roger S. Preston
Life of this patent
Estimating the term…
Abstract
An extrnal fibre drawing furnace is maintained at or close to its normal working temperature while contaminants are removed between fibre pulls. Either a removable insert, replaceable gas port assembly, or cleanable gas transfer duct, enable this to be achieved while the furnace is maintained at or near its operating temperature, so that the down time is of the order of minutes rather than hours.
Claims8
A method of operating an optical fibre drawing furnace having a preform entrance and fibre exit, comprising providing the furnace with a duct, running the furnace at a temperature in the range suitable for drawing optical fibre from a preform, melting a preform in the furnace progressively and drawing a fibre from the preform, extracting gases from the duct so that contaminants produced by the drawing process traverse said duct, and become deposited on said duct, ceasing drawing said fibre, and, while maintaining the furnace at or near said temperature, and closing the entrance and exit, removing the deposited contaminant, and finally drawing further fibre from a fibre preform in the furnace after opening the entrance and exit.
An optical fibre drawing furnace having a preform entrance and fibre exit, a duct, means for running the furnace at a temperature suitable for drawing optical fibre through the exit from a preform by progressively melting the preform entering through the entrance in the furnace, means coupled to said duct for extracting gases from the furnace through the duct whereby contaminants produced by the drawing process will traverse said duct so that said contaminants become deposited on said duct, said duct being removably secured to the furnace so that the deposited contaminants carried by the duct can be removed from the furnace with the duct, while the furnace is maintained at or near said temperature.
Dependencies are inferred from the claim text.