| 摘要 |
PROBLEM TO BE SOLVED: To provide a pump gate capable of opening/closing a water stop gate door body according to relatively easy judgement by allowing the natural drain of the water stop gate door body in a closed condition from an inside water area to an outside water area to inhibit the increase of an inside water level to a starting water level of a vertical pump and giving less frequent operation/stop to the vertical pump to be protected. SOLUTION: A passage 10 facing the outside water area 8 in communication with a suction passage 4 facing the inside water area 5 is provided at the lower part of the water stop gate door body 1 and a natural drain passage 11 for communicating the inside water area 5 with the outside water area 8 is formed by the passage 10 and the suction passage 4. An exit of the natural drain passage 11 is provided with a flap valve 12 in a closeable manner for preventing backflow from the outside water area 8 into the inside water area 5.
|
