| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a liquid displacement pump that prevents check valves on the suction side and the discharge side of a pump room from generating gas-lock phenomenon even when treating foaming liquid or liquid containing bubbles. <P>SOLUTION: The liquid displacement pump is configured to alternately and continuously perform a suction step of supplying liquid to a pump room 3 from a suction passage 9 via a suction side check valve 8 and a suction port 6 by increasing the volume of the pump room 3, and a discharge step of supplying the liquid to a discharge passage 9 from the pump room 3 via a discharge port 7 and a discharge side check valve 10 by decreasing the volume of the pump room 3. In treating the liquid generating bubbles in the pump room 3, an upper area of the pump room 3 and the discharge passage 9 are directly connected to each other via a micro hole passage 14, and a slight amount of liquid in the pump room 3 is made to flow from the micro hole passage 14 to the discharge passage 9 in the discharge step. Thus, bubbles in the pump room 3 are eliminated so as not to cause any gas lock phenomenon in the check valves 8, 10. <P>COPYRIGHT: (C)2012,JPO&INPIT |
