(19)
(11) EP 1 314 891 A8

(12) CORRECTED EUROPEAN PATENT APPLICATION

(48) Corrigendum issued on:
15.10.2003 Bulletin 2003/42

(43) Date of publication:
28.05.2003 Bulletin 2003/22

(21) Application number: 02257645.8

(22) Date of filing: 05.11.2002
(51) International Patent Classification (IPC)7: F04D 19/04, F04D 29/02, F04D 29/58
(84) Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR
Designated Extension States:
AL LT LV MK RO SI

(30) Priority: 16.11.2001 JP 2001352256

(71) Applicant: BOC Edwards Technologies, Limited
Narashino-shi, Chiba 275-0004 (JP)

(72) Inventors:
  • Takaminie, Masayoshi
    Narashino-shi, Chiba 275-0004 (JP)
  • Maejima, Yasushi
    Narashino-shi, Chiba 275-0004 (JP)
  • Kawanishi, Shinji
    Narashino-shi, Chiba 275-0004 (JP)
  • Sakaguchi, Yoshiyuki
    Narashino-shi, Chiba 275-0004 (JP)
  • Okudera, Satoshi
    Narashino-shi, Chiba 275-0004 (JP)
  • Kabata, Kenji
    Narashino-shi, Chiba 275-0004 (JP)
  • Inayoshi, Yutaka
    Narashino-shi, Chiba 275-0004 (JP)

(74) Representative: Sturt, Clifford Mark et al
Miller Sturt Kenyon 9 John Street
London WC1N 2ES
London WC1N 2ES (GB)

   


(54) Vacuum pump


(57) A vacuum pump has a pump case (1) forming a gas suction port (2) at the upper surface thereof; a rotor shaft (5) rotatably supported in the pump case; a rotor (8) being formed a corrosion-resistant film treated by nonelectrolytic plating on the inner and outer circumferential surfaces (8b, 8a) of the rotor; a plurality of rotor blades (10) accommodated in the pump case and integrally formed with an outer circumferential surface of the rotor; a plurality of stator blades (11) fixed in the pump case such that the rotor blades and the stator blades are alternately positioned and arranged; a drive motor (9) for rotating the rotor shaft; and mass-addition means (15) formed by applying an adhesive or a coating, having heat and corrosion resistances, on the inner circumferential surface of the rotor.