US Patent 7803429 Method of coating fibers

Disclosed are fiber coating sizing applicator apparatus having a member to remove unused sizing and foreign objects from the fiber coating element of the applicator on a continuous or intermittent basis. Also disclosed are sizing applicators having as part of the drive, a servo motor for reduced variation in sizing application. Unused sizing is filtered to remove foreign objects and returned the applicator right away, or stored in a temperature controlled area until ready to feed back to a sizing applicator. Also disclosed are methods of using the sizing applicator apparatus to produce sized fibers. The apparatus and methods of the invention produce a substantial reduction in the fiber break rate, sizing usage and applicator maintenance.