| 摘要 |
PURPOSE:To prevent the internal pressure of a reactor holding starting materials for glass from sensitively responding to a change in the volumes of gases fed by attaching a mechanism regulating the volume of air sucked to an exhaust pipe at the exhaust side of the reactor. CONSTITUTION:While evacuating a reactor 6, a flame 5 contg. fine glass powder is produced with a burner 1 for flame hydrolysis to grow a porous glass base material 2. At this time, the internal pressure of the reactor 6 is detected with a detector 15, and tge signal is fed back to a gas feed regulator 19 or 19' through a control section 18. The flow rates of gases in the directions of arrows 21'', 21''', 23, 23', 23'' are made constant. Holes 24 are cut in an exhaust pipe 13, and by sucking air from the holes in the directions of arrows 25, 25', 25'', exhaust gas 14 is mixed with the air bias and becomes a flow 26. As the size and number of the holes 24 are made larger, the volume of air sucked is increased, and a pressure change to a change in the volumes of gases fed is relaxed easily. |
