Abstract: To effectively block a corner portion from an influx of water. A floating flap gate apparatus 1 constructed to enable a forward end of a door body to swing upwards around a base end thereof. The floating flap gate system 1 has floating flap gates 11 and 12 arranged in a first rectilinear region S1 and a second rectilinear region S2 respectively, and a corner flap gate 21 installed at a corner portion C where S1 and S2 intersect. The corner flap gate 21 has a plurality of door bodies 22 divided by straight lines passing through a part of the corner portion C where lines extending in a width-wise direction of a base end side bottom surface of the door bodies 13 of the floating flap gates 11 and 12 intersect. Among the plurality of door bodies 22, a door body adjacent to the door bodies 13 of the floating flap gates 11 and 12 and the door bodies 22 adjacent to the door bodies 13 are connected by hinge structures 32 and 31 that maintain a water-impervious state.

Abstract: A flood prevention device includes a gate device constituting a passage between a flood prevention area and an outside area, and a portable flood prevention material that separates the flood prevention area and the outside area with the gate device. The gate device has a side wall corresponding to one end of the portable flood prevention material.

Abstract: An axis positioning mechanism serving as a rotation bearing of a flap gate includes a housing disposed at the bottom of an opening, a first rotating plate rotationally supported by the housing via a first shaft, a second rotating plate rotationally supported by the housing via a second shaft having a different axis from the first shaft, and a synchronizing rod rotationally connected to the rotating plates so as to synchronize the rotations of the rotating plates. The axis positioning mechanism further includes connecting members rotationally connecting a door base and the rotating plates with different axes. The door is laid flat with a pivot at a higher position than the axes.

Abstract: A flood prevention device includes a gate device constituting a passage between a flood prevention area and an outside area, and a portable flood prevention material that separates the flood prevention area and the outside area with the gate device. The gate device has a side wall corresponding to one end of the portable flood prevention material.

Abstract: An axis positioning mechanism serving as a rotation bearing of a flap gate includes a housing disposed at the bottom of an opening, a first rotating plate rotationally supported by the housing via a first shaft, a second rotating plate rotationally supported by the housing via a second shaft having a different axis from the first shaft, and a synchronizing rod rotationally connected to the rotating plates so as to synchronize the rotations of the rotating plates. The axis positioning mechanism further includes connecting members rotationally connecting a door base and the rotating plates with different axes. The door is laid flat with a pivot at a higher position than the axes.

Abstract: To make it possible to raise a door body even if it is damaged by an impact of vehicle traffic or falling objects when it is in a lowered state, and to keep the door body in a raised state even if it is damaged by a water pressure of a tsunami or a high tide when it is in a raised state. A door body 2 of a floating flap gate 1 is disposed at an opening or at an access way. When water flows in, a forward end 2b of which swings upwards, in a direction in which the water flows in and within a plane in a height direction, around a base end 2a thereof which serves as a center of rotation, to block the opening or the access way. The door body 2 is formed from a hard polyurethane foam 4 in the form of a sheet.

Abstract: A floating flap gate to prevent water from overflowing into underground spaces, with ease in raising or lowering the door body when water level changes. The floating flap gate comprises a door body with a forward end which swings upwards or downwards in a same direction following a rise or a drop in water level, wherein an opposite end serves as a fulcrum. A rod is attached to the forward end of the door body. One end of a wire rope is attached to the rod, and the other end is attached to a counterweight via fixed pulleys. The fixed pulleys are arranged so that the counterweight is at its lowest point when the angle of inclination of the door body with respect to a horizontal plane reaches within a range from 10° to 80° during raising or lowering of the door body.

Abstract: The present invention utilizes a vertically upward force of a water when a tsunami smashes into a building to close openings that exist in an elevated location such as air supply and exhaust ducts, powerlessly and without a manual operation. The present invention serves as a disaster prevention panel which closes an opening 2a disposed in a wall of a building 2. A door bumper 3 is disposed on an outer peripheral wall of the opening 2a, and side door bumpers 4 are disposed on both sides of the door bumper 3. A door body 1, which closes the opening 2a and which has a specific gravity lower than a seawater, is attached between the side door bumpers 4 on both sides so as to freely swing upwards, with a lower portion of the door bumper 3 serving as a fulcrum.

Abstract: The present invention utilizes a vertically upward force of a water when a tsunami smashes into a building to close openings that exist in an elevated location such as air supply and exhaust ducts, powerlessly and without a manual operation. The present invention serves as a disaster prevention panel which closes an opening 2a disposed in a wall of a building 2. A door bumper 3 is disposed on an outer peripheral wall of the opening 2a, and side door bumpers 4 are disposed on both sides of the door bumper 3. A door body 1, which closes the opening 2a and which has a specific gravity lower than a seawater, is attached between the side door bumpers 4 on both sides so as to freely swing upwards, with a lower portion of the door bumper 3 serving as a fulcrum.

Abstract: To make it possible to raise a door body even if it is damaged by an impact of vehicle traffic or falling objects when it is in a lowered state, and to keep the door body in a raised state even if it is damaged by a water pressure of a tsunami or a high tide when it is in a raised state. A door body 2 of a floating flap gate 1 is disposed at an opening or at an access way. When water flows in, a forward end 2b of which swings upwards, in a direction in which the water flows in and within a plane in a height direction, around a base end 2a thereof which serves as a center of rotation, to block the opening or the access way. The door body 2 is formed from a hard polyurethane foam 4 in the form of a sheet.

Abstract: The object of the present invention is to prevent an overflow of water into living spaces and underground spaces, to prevent difficulties in lower the door body when the water level has dropped, and to prevent the door body from suddenly falling. This is achieved by a floating flap gate 11 which is disposed at an opening or at an access way, so as to block the opening or the access way when water w flows in, and comprises a door body 12 with a forward end which is able to swing upwards, within in a plane in a height direction in a direction in which the water flows in around a base end thereof serving as a fulcrum. A rod 13 is attached to the forward end of the door body 12. One end of a wire rope 14 is attached to the rod 13, and the other end is attached to a counterweight 20 via fixed pulleys 16, 17.