| 摘要 |
<p>An apparatus and method for the thermal treatment of an object, such as a glass optical fiber preform. The downtime of an optical fiber drawing apparatus can be considerably shortened, by providing preforms which have pre-optimized draw bulbs (30). Pre-optimized draw bulbs (30) are provided which are already appropriately melted off at the tip. A heating furnace (1) is used for such thermal pretreatment (pre-optimization) of the preforms (2) and which does not contaminate the quartz glass. Utilizing preforms (2) which have pre-optimized draw bulbs advantageously increase throughput of the draw apparatus. In accordance with one embodiment, a heating furnace (1) that meets these requirements includes a cylindrical heating chamber (3-5), heat insulation (6-9) surrounding the heating chamber on all sides, several gas burners (12-13) firing onto the tip of the rotating preform (2) through lateral heating chamber openings (10-11), and a frame (14). Since the preform (2) softens after a temperature of about T > 1750 °C, correspondingly high temperatures must be generated in the heating chamber (3-5). Therefore, both the heating chamber (3-5) and the gas burners (12-13) are made of quartz glass or a ceramic material.</p> |
