| 摘要 |
PURPOSE:To eliminate the buckling of a bellows in use so as to extend the lifetime of the bellows, by closing bellows space including a shaft installed in a vessel, and by keeping the space at a press. lying between the outside atmospheric press. and the inside press. CONSTITUTION:A shaft 6 is installed in a vacuum vessel 1 rotatably and vertically movably at the top end 9 of a bellows 3 through an O-ring 10. A flange 14 is set to the bellows 3 space, which includes a shaft 6, through O-rings 12, 13 to form a second closed space 11. The press. in the bellows 3 is decreased by evacuating the closed space 11 through a suction pipe 15 to alleviate the press. difference between the outside press. and the press. in the vessel 1 with the press. in the bellows 3 Hereby, bellows 3 moves smoothly, causing no buckling. As a result, the shaft 6 hardly intermeshes with the bellows 3 and is operated easily. |
