| 摘要 |
PURPOSE:To enhance the strength of a fiber for light transmission by heating a crucible having a bottom opening to a high temp. and feeding a preform into the heated crucible followed by glass surface temp. raising, rapid cooling and spinning. CONSTITUTION:Cylindrical carbon heater 21 set in carbon capsule 24 in metal container 25 is electrified through water-cooled electrode 21'' and carbon support 21' to generate heat. Pipe-shape crucible 27 is placed in heater 21, and tip 27' is contracted. Preform 22 is fed into crucible 27 at a fixed speed, melted at tip 27' portion, and spun into fiber 23. By providing the top and bottom of crucible 27 with water- cooled coils or boxes, only the vicinity of crucible 27 is held at a high temp. By this method a glass fiber uniformly heat treated in the circumferential direction is obtd. stably. |
