Patent ID: 8827275
Filing Date: 2014-09-09
Classification: F16J

Abstract:
1. A vacuum substrate coating installation comprising a housing wall separating a vacuum in the installation from atmosphere outside of the installation, and a vacuum-tight rotary feedthrough disposed in and applied to the housing wall, the vacuum-tight rotary feedthrough comprising: a sealing device and a rotating machine element disposed in and rotatable relative to the sealing device, the sealing device comprising at least two sealing elements disposed in tandem in an axial direction of the rotating machine element, each of the at least two sealing elements having an axially extending sealing lip forming an active vacuum-tight sealing connection with the rotating machine element, the axially extending sealing lip of an outer sealing element being directly exposed to the atmosphere, the axially extending sealing lip of an inner sealing element extending between the vacuum and an intermediate vacuum generated between the inner sealing element and the outer sealing element and the rotating machine element by a gas suction duct, and a spring element applying to the inner sealing element an additional force acting in a radial direction so that total force of compression acting on the inner sealing element is the same as a force of compression caused by atmospheric pressure acting on the outer sealing element, wherein the inner sealing element acts as a membrane in cooperation with a cavity encircling the axially extending sealing lip of the inner sealing element, the cavity being directly continuously connected to the atmosphere to produce the additional radial force.