| 摘要 |
PROBLEM TO BE SOLVED: To provide a thread groove type vacuum pump, a composite pump and a vacuum pump system capable of providing favourable exhaust speed. SOLUTION: A rotor member 60 and a stator member fixed and arranged on the same shaft with the rotor member 60 and having an opposed wall to face against a peripheral wall of the rotor member 60 are furnished, a thread groove 62 to transfer gas in accordance with rotation of the rotor member 60 is formed on the peripheral wall of the rotor member 60, depth D of the thread groove 62 is more than 20 mm on the extreme side of an air suction port 16, it is reduced gradually from the side of the air suction port 16 to the side of an exhaust port 17, it is more than 80% of depth on the extreme side of the air suction port 16 up to 40 mm in the axial direction from the side of the air suction port 16, inclinationθagainst the diametrical direction of the thread groove 62 gradually reduces toward the side of the exhaust port 17 from the side of the air suction port 16 and it is made more than 80% of inclination at the air suction port 16 up to 40 mm in the axial direction.
|
