Gap seal

摘要

Gap seal for sealing off the interior in a housing from the outside, a rotating shaft with a revolving ring leading into the housing and a sealing gap being formed between this and a fixed sealing ring. One of the boundary surfaces of the sealing gap has spiral grooves 18, 19 that leave free a spiral-free margin 23, 24 at the inner and outer edges. Formed in the region of the spiral grooves 18, 19 is an annular groove 20 which can be supplied with sealing gas and feeds it to the spiral grooves. In the annular boundary surface of the sealing gap, the spiral grooves 18, 19 run symmetrically - as seen in the direction of running - with respect to their curvature away from the annular groove 20 towards the spiral-free edge 23, 24 acting as a barrier, the symmetry applying both in the region of the annular surface outside the groove 20 and in the annular region enclosed by the groove 20. <IMAGE>