| 摘要 |
PURPOSE:To control accurately and easily the temp. distrubution of an oxyhydrogen flame, in hydrolysis of glass component-contg. raw material with the flame, by circularly jetting O2 and H2 as combustion gases and by burning the gases while enabling the no. of the gas rings to increase or decrease in a coaxial state to regulate the flame in the diametrical direction. CONSTITUTION:When liquefied raw material is fed into jet pass 5 of jet pipe 2, it is optionally vaporized with a heater (not shown) at the lower end of pipe 2 and jetted form the top of pipe 2. At the same time, Ar or the like is fed into jet pass 6 of flame protection pipe 3 and jetted from the tip of pipe 3, and O2 and H2 are supplied into jet passes 7, 8 of oxyhydrogen gas pipes 4a-c, respectively. The gases are jetted as circular multiple combustion gases from the tips of pipes 4a-c and burned to form and oxyhydrogen flame. The raw material is jetted from the center of the flame and hydrolyzed with the flame. The resulting oxide powder is adhered and deposited to a place for depositing the powder. By this method the no. of the combustion gas rings is suitably added or reduced to vary the size of the flame in the diametrical direction, whereby the temp. distribution of the flame is controlled to rpoduce a base material for optical fiber with a desires refractive index. |
