| 摘要 |
PURPOSE: To reduce the stress of a packing and to reduce wear so as to lengthen a service life by covering the inner wall of a bore provided in a partition wall of a vacuum chamber, with a plastic sleeve of small friction, and closing the sleeve itself with a packing ring. CONSTITUTION: An inner wall 2 of a bore is covered with a bush or a sleeve 3. The outside of the sleeve 3 adheres closely to the inner wall 2 of the bore, and the sleeve 3 is closed with a packing ring 5 fitted into a ring nut 4. A shaft 6 for transmitting rotation pierces the sleeve 3. In order to fix the sleeve 3 onto the shaft 6, the diameter of the shaft 6 is increased on one side of a partition wall, and the sleeve 3 is connected to an annular disc 7 by a screw 8 on the other side and fixed to the shaft 6. The thermal excessive stress of the packing is thus relaxed, and wear is reduced so as to lengthen a service life. |
