Title:
IMPROVED VACUUM PUMP
Document Type and Number:
Japanese Patent JP2001304156
Kind Code:
A
Abstract:
To provide a screw type vacuum pump, particularly a pump with an improved screw thread design.
This vacuum pump comprises a pump body 20 having two rotors 7, 8 with male screw thread mounted thereon. Screw thread profile of each rotor is tapered substantially radially to facilitate machining and fit of the rotors 7, 8 in a required strict allowance.
Inventors:
NORTH MICHAEL HENRY
Application Number:
JP2001102099A
Publication Date:
October 31, 2001
Filing Date:
February 23, 2001
Export Citation:
Assignee:
BOC GROUP PLC
International Classes:
F04C18/08; F04C18/16; F04C25/02; (IPC1-7): F04C18/16; F04C25/02
Attorney, Agent or Firm:
Minoru Nakamura (9 outside)