PURPOSE: To obtain a turbomolecular pump having a high compression ratio and not having an auxiliary pump which can exhaust into the atmosphere.
CONSTITUTION: A tangential flow pump stage 10 is arranged in an exhaust side in addition to plural axial flow pump stages consisting of alternately arranged rotor 12 and stator 13 in order to raise a compression ratio. Each tangential flow pump stage is composed of a common surface ring shape stator separating and surrounding a plane disc rotor. A force-fed gas is moved in the tangential flow direction in the ring shape free passage 14. The free passage is intercepted by a baffle 15 and communicated with an intake port 17 and exhaust port 18. Thereby, the exhaust pressure is raised upto the atmospheric pressure and also exhausted directly to the atmosphere.
RUIJI DORUCHINO
MARUSU HABURANIAN
JIYANPAORO REBI
| JPH0249996A | 1990-02-20 | |||
| JPS63280893A | 1988-11-17 | |||
| JPH01247794A | 1989-10-03 | |||
| JPH01170795A | 1989-07-05 |