| 摘要 |
The present invention provides a vacuum pump (10) which comprises a turbo-molecular pumping mechanism (12) in series with a Siegbahn pumping mechanism (14). A first pump inlet (16) is provided through which gas can pass through both the turbo-molecular pumping mechanism and the Siegbahn pumping mechanism. Additionally, an inter-stage (inlet 18) is provided through which gas can enter the pump at a location between the turbo-molecular pumping mechanism and the Siegbahn pumping mechanism and pass only through the Siegbahn pumping mechanism. There are flow channels (52, 62) in a first plurality of stages (32, 34) of the Siegbahn pumping mechanism which are in fluid communication with the inter-stage inlet (18) and gas entering the pump through the inter-stage inlet is pumped in parallel along said flow channels. |
