Title:
VACUUM PUMP
Document Type and Number:
WIPO Patent Application WO/2004/079197
Kind Code:
A1
Abstract:
A vacuum pump, comprising a pair of screw rotors having a first screw rotor with a plurality of spiral land parts and a second screw rotor with a plurality of spiral groove parts and rotating about two axes substantially parallel with each other while being engaged with each other, a casing storing the pair of screw rotors, and a pair of bearings installed on a pair of shafts (4) supporting the pair of screw rotors. The vacuum pump is characterized in that a pair of shaft seals (5) in non-contact with the pair of shafts (4) are installed between the pair of screw rotors and the pair of bearings, and each of the pair of shaft seals (5) is of a static pressure type and leads seal gas through a shaft seal portion.
Inventors:
OHMI TADAHIRO (JP)
Application Number:
PCT/JP2004/002360
Publication Date:
September 16, 2004
Filing Date:
February 27, 2004
Export Citation:
Assignee:
OHMI TADAHIRO (JP)
International Classes:
F04C25/02; F04C27/00; F16J15/40; F04C18/16; (IPC1-7): F04C25/02; F04C27/00; F04C18/20
Foreign References:
| JPH11270482A | 1999-10-05 | |||
| JPS63285279A | 1988-11-22 | |||
| JP2000213488A | 2000-08-02 | |||
| JPS62184191U | 1987-11-21 | |||
| JP2001056027A | 2001-02-27 |
Attorney, Agent or Firm:
Goto, Yosuke (4-10 Nishishinbashi 1-chom, Minato-ku Tokyo, JP)
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