| 摘要 |
PURPOSE:To maintain vacuum stably in winding chamber by forming a preliminary vacuum chamber at the bearing section of winding shaft while maintaining vacuum in preliminary vacuum chamber at predetermined level. CONSTITUTION:A winding shaft 15 is mounted with roll bearings 18, 19 on the cross-section of projected section of vacuum winding chamber 13 and fastened with a collar 35. A space 37 is provided at the cross-section of projection and said shaft 15 and evacuated through a suction port 33 made in a bearing stopper 30 by means of a vacuum pump different from that to be used for evacuation through a suction port 24 to form specific preliminary vacuum chamber to maintain constant vacuum pressure in winding chamber. |
