PROBLEM TO BE SOLVED: To assist a rising operation for a door body and enable deceleration when the rising operation is complete, without increasing a size of a weight.SOLUTION: A land-type floating body-type flap gate 11 has a door body 2 supported at a rear edge side and a tip side that rises and swings. A wire rope 3 has one end fitted to the rear edge part of the door body 2, and a weight 5 fitted on the other end. Stationary pulleys 4a, 4b are installed on the rear edge side of the door body 2 for guiding the wire rope 3, such that the weight 5 reaches the lowermost position midway while the door body 2 is rising or falling, for assisting rising or falling of the door body when rising or falling starts, at the same time functioning as a resistance against rising or falling before completion of rising or falling. For example, the stationary pulley 4a disposed directly above the weight 5 is made to have a radius that increases in size gradually, so that the radius differs between the door body side and the weight side.EFFECT: Assisting of a rising operation of a door body and deceleration before completion of rising become possible without using a large weight, thereby enhancing degree of freedom of design and reducing costs.SELECTED DRAWING: Figure 1
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