| 摘要 |
PROBLEM TO BE SOLVED: To prevent overflow into living spaces or underground spaces from occurring at the beginning of influx, such that a floating flap gate does not swing down suddenly.SOLUTION: In a floating flap gate 11, a distal end side 12b of a door 12 rises and swings with a rotary shaft 12a at a proximal end side as a fulcrum within a plane in a height direction in an influx direction of water (w). One end of a wire rope 15 is connected to the distal end 12b of the door 12 and another end is connected, via fixed pulleys 16, 17, to a position deviated from a center of gravity CG of a counterweight 18 to a lower side of a downstream side. Friction members 19a, 19b are mounted to an upper part of a front face and a lower part of a rear face of the counter weight 18. In the latter half of rising in which the counter weight 18 rises from a bottom point or in the latter half of falling, the friction members 19a, 19b in the upper part of the front face and the lower part of the rear face are brought into contact with an inner wall of a storage section 13a. Thus, start of initial rising is made earlier and overflow at the beginning of influx can be effectively prevented. Furthermore, a swinging-down speed of the door can be reduced for safety. |
