PURPOSE: To prevent the generation of suction shortage even if the fluid which flows through one suction passage into two pump elements by forming a suction introducing passage which communicates to each bypass passage of two pump elements arranged in the longitudinal firection.
CONSTITUTION: The fluid which flows in through one suction passage 12 from a reservoir joins with the fluid in a bypass passage 11a in the first flow rate control part 10a, and the supercharge in the first stage in applied onto the first pump element 2a. A portion of the fluid which is supercharged passes through a suction introducing passage 13, and converges with the fluid in the bypass passage 11b of the second flow rate control part 10b, and the supercharge in the second stage is applied onto the second pump element 2b. Therefore, the second pump element 2b is applied with supercharge in two times, and the sufficient supercharge action is performed even at a position departing far from the suction passage 12, and the suction shortage is not generated even with the equipment which needs a large flow rate. Further, the dimension of the pump can be reduced, and the simple piping is permitted.
| WO/2003/025399 | WING CELL PUMP |
| JP4821673 | Vane pump |
| JPS5229605 | ROTARY TYPE FLUID PUMP |
INAGUMA YOSHIHARU
KATOU TOSHIYA
