PURPOSE: To stabilize the pump performance and facilitate assembling by arranging a centrifugal compression pump stage, a circumferential flow compression pump stage and an axial flow vane type circumferential compression pump stage from the suction port 21A side.
CONSTITUTION: A centrifugal compression pump stage 24, a circumferential flow compression pump stage 25 and an axial flow vane type circumferential compression pump stage 27 are arranged in sequence in a housing 21 from the suction port 21A side to the discharge port 21B side. The circumferential flow compression pump stage 25 and the axial flow vane type circumferential compression pump stage 27 operated in a viscous flow are used in the proper pressure area. The pump performance can be thereby stabilized. When the same compression ratio as that of only the circumferential flow compression pump stage 25 is obtained in the viscous flow, the number of stages can be decreased, and the cost can be reduced.
MASE MASAHIRO
OKAWADA TAKESHI
| JPS61247893A | 1986-11-05 | |||
| JPS6336096A | 1988-02-16 |