| 摘要 |
PURPOSE:To maintain water conveyance amount of a pump constant in a pumping up installation when at least one of high and low water levels varies, by providing a check valve and a water level variation buffer tank respectively between the pump and a water level varying portion and between the check valve and the pump. CONSTITUTION:A pump 6 pumps up water from a low level portion 1 to a high level one 2, assuming that the water level in the low level portion varies between the upper and lower limits 4, 5 with reference to average water level 3. A check valve 7 permitting water to pass only in the water feed direction and an air chamber 8 as a buffer tank are provided between the low water level portion 1 and the pump 6 and water level in the air chamber 8 is balanced as the average water level 3. When the water level in the low water level portion 1 rises to a varied water level 4, this rise is absorbed and buffered in the chamber 8. Also, when the water level is lowered lower than that in the chamber 8, the check valve 7 is closed to feed water-in-the chamber 8 so that water flow of the pump is maintained constant. |
