Vacuum pump
AssigneeHitachi, Ltd.
InventorsAkira Nishiuchi, Masahiro Mase, Noboru Matsumura, Katsuaki Kikuchi, Takashi Nagaoka
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Abstract
A dry turbo vacuum pump has a multistage circumferential impeller supported on a shaft, and a stator which cooperates with it to form a multistage peripheral flow pump. A centrifugal pump arranged at an inlet side of the peripheral flow pump is also mounted on the same shaft, so that gas sucked from the inlet is discharged to the atmosphere from the peripheral flow pump. The multistage peripheral flow pump and at least one stage of the centrifugal pump are integrated.
Claims8
A dry turbo vacuum pump comprising:
- a housing having an inlet and an exhaust duct;
- a shaft rotatably supported in said housing;
- a multistage peripheral flow impeller secured on said shaft and located in said housing;
- and
- at least a first centrifugal impeller disposed at an inlet side of said peripheral flow impeller, whereby gas sucked from said inlet is discharged through said exhaust duct;
- wherein said peripheral flow impeller is integrated with said at least a first centrifugal impeller to form a unitary pump rotor.
A dry turbo vacuum pump comprising:
- a housing having an inlet and a exhaust duct;
- a shaft rotatably supported in said housing;
- a multistage peripheral flow impeller secured on said shaft and located in said housing;
- and
- at least a first centrifugal impeller disposed at an inlet side of said peripheral flow impeller whereby gas sucked from said inlet is discharged through said exhaust duct;
- said housing further comprising,
- a multistage stator disposed between said inlet and said exhaust duct, which cooperates with said peripheral flow impeller to form a multistage peripheral flow pump having walls arranged between the stages;
- wherein inner diameters of at least two neighboring stages of said housing are substantially identical;
- and
- wherein a surface of said walls is substantially flat.
A dry turbo vacuum pump comprising:
- a housing having an inlet and an exhaust duct.
Dependencies are inferred from the claim text.