Method of using bushing environmental control in glass fiber forming
Patent 4146377 Issued on March 27, 1979. Estimated Expiration Date: August 17, 1997. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
A method is disclosed for maintaining a uniform airflow and thus uniform thermal conditions below a bushing in a continuous glass fiber forming operation. The method comprises passing the glass filaments through an enclosure and blowing a gaseous fluid through the enclosure co-current with the filaments at a substantially constant volume and velocity to draw air downwardly with the filaments from all directions below the bushing at a substantially constant volume and velocity which thus provides a more uniform airflow and temperature below the bushing. The downward airflow velocity is insufficient to attenuate the filaments. Suitable apparatus for accomplishing this result is also disclosed. This apparatus comprises an enclosure for the filaments having a pair of chambers, the glass filaments being passed through the inner chamber and gaseous fluid being flowed from the outer chamber to the inner chamber at a substantially constant volume and velocity to flow co-current with the glass filaments.