| 摘要 |
PURPOSE:To thoroughly remove bubbles from molten glass and to obtain a glass fiber of high quality by introducing the molten glass into a vessel provided with an uneven bottom and partition plates opposing to the recesses. CONSTITUTION:Core glass or sheath glass for a glass fiber for transmitting light or image is melted and poured into a vessel 5 at a constant rate. Bubbles 10 existing in the molten glass 9 flow from the outside of the vessel 5 to the center. At this time, since the bottom 6 of the vessel is uneven, bubbles 10 acceleratedly rise from each recess 11 to each protrusion 12, and they are released into the air at the shallowest place of the molten glass 9 between the surface of the glass 9 and the protrusion 12. Even if the bubbles pass through the place, they are interrupted by a partition plate 7 without settling again and released into the air after rising. The unevenness and the partition plate 7 are set in many steps, and the glass 9 is freed of microbubbles having about several mum size as well as bubbles. The glass 9 is then spun by dropping from a nozzle 8 attached to the bottom of the vessel 5 at a central part. When both core glass and sheath glass are melted, the positions of nozzles are adjusted to spin them. |
