| 摘要 |
PURPOSE:To prevent deterioration in quality such as cracking or the like by forming the butt contact parts between a ceramic shaft and a metallic shaft to the diameter smaller than the finish diameter of the ceramic shaft thereby preventing thermal cracking of the ceramic shaft and eliminating oscillation in finishing by grinding. CONSTITUTION:The butt contact parts d2 and d4 between a ceramic shaft 27 and a metallic shaft 21 are made to the diameter smaller than the finish diameter d1 of the ceramic and are subjected to brazing 29 by heating. The generation of thermal stress cracking of the ceramics owing to a difference in the coefft. of expansion between both shafts is prevented. The much better result is obtd. if the end of the ceramics 27 is preliminarily chamfered in this stage. Since the ceramics 7 is a hardly machineable material, the margin for finish grinding is made as small as possible but even if the brazing material 29 has a wetting and oozing part 30 in the stage of grinding, said part does not contact with a grindstone and therefore the ceramic is finished without grinding oscillation and a crack, etc. are not induced. The deterioration in quality is thus obviated. |
