Vacuum pumps with improved impeller configurations
AssigneeVarian, Inc.
InventorMarsbed Hablanian
Life of this patent
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Abstract
A vacuum pump includes a housing having an inlet port and an exhaust port, a plurality of vacuum pumping stages located within the housing and disposed between the inlet port and the exhaust port, and a motor. The vacuum pumping stages include gas drag stages, each including a stator and an impeller. The impellers of successive ones of the gas drag stages are configured for efficient operation at progressively higher pressures. The impellers of the gas drag stages may have pumping surfaces with a surface topography for efficient operation at progressively higher pressures. The motor rotates the impellers such that gas is pumped from the inlet port to the exhaust port.
Claims18
A vacuum pump comprising:
- a housing having an inlet port and an exhaust port;
- a plurality of vacuum pumping stages located within said housing and disposed between said inlet port and said exhaust port, said vacuum pumping stages comprising transition and viscous flow gas drag stages disposed in proximity to said exhaust port, each including a stator and an impeller, wherein each successive impeller of respective transition and viscous flow gas drag stages has a pumped gas engaging surface having a predetermined topography of said pumped gas engaging surface greater than the preceding one for efficient operation at progressively increased toward said exhaust port higher pressures;
- and
- a motor for rotating said impellers such that gas is pumped from said inlet port to said exhaust port.
A vacuum pump comprising:
- a housing having an inlet port and an exhaust port;
- a plurality of vacuum pumping stages located within said housing and disposed between said inlet port and said exhaust port, said vacuum pumping stages comprising molecular drag stages and transition and viscous drag stages of different geometric configurations, each including a stator and an impeller having different predetermined topography of a pumping surface, wherein the impellers of successive ones of said transition and viscous drag stages have pumping surfaces with the surface topography for efficient operation at progressively increased toward said exhaust port higher pressures;
- and
- a motor for rotating said impellers such that gas is pumped from said inlet port to said exhaust port.
Dependencies are inferred from the claim text.