Title:
VACUUM PUMP
Document Type and Number:
WIPO Patent Application WO/2000/058628
Kind Code:
A1
Abstract:
A vacuum pump having a screw groove pump part capable of assuredly preventing a rotor cylindrical body from being abnormally close to or in contact with a stator cylindrical body, wherein an air gap sensor which detects an air gap formed on the inner peripheral surface (22a) near the bottom of the stator cylindrical body (22) and between an outer peripheral surface (12a) of the rotor cylindrical body (12) and an inner peripheral surface (22a) of the stator cylindrical body (22) is installed in a composite type turbo molecular pump, which comprises the rotor cylindrical body (12) and the stator cylindrical body (22) and has a screw groove pump part in which threads are formed in the inner peripheral surface (22a) of the stator cylindrical body (22).
Inventors:
YAMAUCHI AKIRA (JP)
Application Number:
PCT/JP2000/002061
Publication Date:
October 05, 2000
Filing Date:
March 31, 2000
Export Citation:
Assignee:
SEIKO SEIKI KK (JP)
YAMAUCHI AKIRA (JP)
YAMAUCHI AKIRA (JP)
International Classes:
F04D19/04; F04D27/02; (IPC1-7): F04D19/04
Foreign References:
| JPH0116774A | ||||
| JPH11280690A | 1999-10-15 | |||
| JPH1172097A | 1999-03-16 | |||
| JPS60104107U | 1985-07-16 |
Attorney, Agent or Firm:
Sakanoue, Masaaki c/o SEIKO INSTRUMENTS INC. 8 (Nakase 1-chome Mihama-ku Chiba-shi, Chiba, JP)
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