Method and apparatus for elongating glass rod material

摘要

A method and apparatus for elongating glass base material by sequentially feeding rod-like glass base materials (5) hung by a feeding mechanism (2) into a heating furnace (1), and pulling a glass rod to a smaller diameter by a pulling chuck (7) situated below the heating furnace (1). An alignment guiding device (14) guides the glass rod (10), with its guiding centre coinciding with the axis of the glass rod (10), and the alignment guiding device (14) guides the glass rod (10) at a position between the heating furnace (1) and the pulling chuck (7).