| 摘要 |
The present invention refers to a rotary vacuum pump (30) comprising a first set (I) of pumping stages having rotor discs with a first diameter (D1) and a second set (II) of pumping stages having rotor discs (D2) with a second different diameter and further comprising an intermediate pumping stage (1) that is particularly adapted for matching said change in the diameter of the pump rotor discs. According to the invention, said intermediate pumping stage comprises a rotor disc (5) having an outer portion in the radial direction that is axially tapered from its inner diameter to its outer diameter and a corresponding stator stage (3) including a spacer ring (7) that is axially tapered from its periphery toward its center. |
