Title:
MAGNETIC BEARING AND TURBO-MOLECULAR PUMP HAVING IT
Document Type and Number:
WIPO Patent Application WO/2005/085663
Kind Code:
A1
Abstract:
A magnetic bearing and a turbo-molecular pump having it in which the cost of manufacturing and installation of the turbo-molecular pump can be reduced by decreasing the number of elements of an amplifier circuit for exciting/driving an electromagnet, and the error can be reduced when the current flowing through the electromagnet is detected. One end (151a) of an electromagnet winding (151) constituting each of electromagnets (104, 105, 106A, 106B) is connected with a common node (C). The common node (C) is connected with a switching circuit (280) composed of a transistor (281) and a diode (285). The other end (151b) of the electromagnet winding (151) is connected with an amplifier circuit (250) composed of a transistor (261) and a diode (265).
Inventors:
KAWASHIMA TOSHIAKI (JP)
Application Number:
PCT/JP2005/003347
Publication Date:
September 15, 2005
Filing Date:
February 28, 2005
Export Citation:
Assignee:
BOC EDWARDS JAPAN LTD (JP)
KAWASHIMA TOSHIAKI (JP)
KAWASHIMA TOSHIAKI (JP)
International Classes:
F16C32/04; F16C39/06; H03F3/217; F04D19/04; (IPC1-7): F16C32/04; F04D19/04; H03F3/217
Foreign References:
| JP2003013954A | 2003-01-15 | |||
| JP2003172353A | 2003-06-20 | |||
| JP2003172354A | 2003-06-20 | |||
| JP2003139136A | 2003-05-14 | |||
| JPH06153479A | 1994-05-31 | |||
| JP2004301322A | 2004-10-28 | |||
| EP1460294A2 | 2004-09-22 | |||
| EP0836022A1 | 1998-04-15 | |||
| EP1460293A2 | 2004-09-22 |
Other References:
See also references of EP 1739318A4
Attorney, Agent or Firm:
Shiina, Masatoshi (10-9 hatchobori 4-chom, chuo-ku Tokyo 32, JP)
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