Patent attributes
A shaft sealing module is proposed for sealing a shaft which extends driving rotationally from a normal pressure chamber into a high vacuum chamber. It is essential for the shaft sealing module according to the invention that the dynamic seal of the shaft takes place not on the shaft itself but on a bushing mounted rotatably in a housing through which is guided a shaft and which is held on the shaft in friction connection, statically sealed, by elastic rings so that the bushing rotates with the shaft. The dynamic seal between the bushing and the housing is achieved by several radial shaft sealing rings which are preferably arranged so that between them is provided a prevacuum chamber with intermediate evacuation so that a two-stage dynamic seal is provided, where the prevacuum acts on the static seal between the bushing and the shaft in the sense of a gas penetration barrier towards the high vacuum chamber.