Abstract: A flap gate includes a door body and a flap ancillary part. When the door body is in its down position, a movable end portion of the door body is located forward of a supported end portion. The door body changes its position between the down position and a maximum up position. The flap ancillary part applies tilt-up moment to the door body only when the door body is located in a position between the down position and a first position. The flap ancillary part also applies tilt-down moment to the door body only when the door body is located in a position between the maximum up position and a second position.

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 flap gate includes a door body and a flap ancillary part. When the door body is in its down position, a movable end portion of the door body is located forward of a supported end portion. The door body changes its position between the down position and a maximum up position. The flap ancillary part applies tilt-up moment to the door body only when the door body is located in a position between the down position and a first position. The flap ancillary part also applies tilt-down moment to the door body only when the door body is located in a position between the maximum up position and a second position. This simplifies the structure of the flap gate that can speedily start to tilt up when water flows in and that can early start to tilt down when the water level has started to drop.

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: Described herein is a floating flap gate including a gate leaf having a buoyancy forming portion, the gate leaf being configured to be raised due to buoyancy effect (e.g., from water), a bottom fitting mounted to a proximal end portion of the gate leaf, the bottom fitting having a convex circular arc-shaped surface across a width direction of the gate leaf, a plate member having a concave circular arc-shaped surface to be mated with the convex circular arc-shaped surface of the bottom fitting when the gate leaf is in a lowered state, wherein the concave circular arc-shaped surface is in contact with the convex circular arc-shaped surface when the gate leaf is raised.

Abstract: In order to structurally simplify a frame that is a component of a door body and to reduce required levels of manufacturing precision and assembly precision, thereby reducing a manufacturing man-hour, provided is a floating flap gate 1 installed on a road surface rs at an entrance portion of a building or an underground space. An upward swinging support portion is composed of a bottom fitting 5, a resin plate 6 configured to support a door body 4 when the door body 4 is raised, a water cut-off film 13 covering the bottom fitting 5 and the resin plate 6, a first pressing plate 14, and a second pressing plate 16. The bottom fitting 5 has a convex circular arc-shaped surface 5a. The resin plate 6 has a concave circular arc-shaped surface 6a to be mated with the convex circular arc-shaped surface 5a of the bottom fitting 5.

Abstract: An apparatus for shutting off the flow of water through ductwork is disclosed that is installed in an air conditioning duct in a building and closes the air conditioning duct in the event of the attack of seawater. Two upper and lower hinged door bodies disposed in the inside of the air conditioning duct are supported by a support device in the state in which the inside of the air conditioning duct is open. The opening and closing operations of the upper door body are interlocked with the opening and closing operations of the lower door body by a chain. A water intrusion detection device releases the supporting of the two upper and lower door bodies in the event of the intrusion of water. The two upper and lower door bodies are horizontally moved in the direction of water pressure when the inside of the air conditioning duct is closed.

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: A land-mounted flap gate formed by arranging and connecting a plurality of door bodies alongside one another is disclosed. The front side of each of the plurality of door bodies is raised and lowered using the back end side of each door body as a support point. One end of a rope is attached to the back end surface of the door body and the other end of the rope is attached to a counter weight. At least one fixed pulley for guiding the rope is disposed below the back end side of the door body such that the counter weight assists the raising or lowering when starting the raising or lowering and acts as a resistance against the raising or lowering before completing the raising or lowering. The waterproof film that seals a space between neighboring door bodies in a waterproof manner is formed in a substantially trapezoidal shape.

Abstract: An apparatus for shutting off the flow of water through ductwork is disclosed that is installed in an air conditioning duct in a building and closes the air conditioning duct in the event of the attack of seawater. Two upper and lower hinged door bodies disposed in the inside of the air conditioning duct are supported by a support device in the state in which the inside of the air conditioning duct is open. The opening and closing operations of the upper door body are interlocked with the opening and closing operations of the lower door body by a chain. A water intrusion detection device releases the supporting of the two upper and lower door bodies in the event of the intrusion of water. The two upper and lower door bodies are horizontally moved in the direction of water pressure when the inside of the air conditioning duct is closed.

Abstract: A land-mounted flap gate formed by arranging and connecting a plurality of door bodies alongside one another is disclosed. The front side of each of the plurality of door bodies is raised and lowered using the back end side of each door body as a support point. One end of a rope is attached to the back end surface of the door body and the other end of the rope is attached to a counter weight. At least one fixed pulley for guiding the rope is disposed below the back end side of the door body such that the counter weight assists the raising or lowering when starting the raising or lowering and acts as a resistance against the raising or lowering before completing the raising or lowering. The waterproof film that seals a space between neighboring door bodies in a waterproof manner is formed in a substantially trapezoidal shape.

Abstract: The present invention provides a floating flap gap which has a door body with a forward end which is able to swing upwards, in a direction in which the water flows into an opening or at an access way, around a base end thereof serving as a fulcrum. The door body is attached to one end of a wire rope, and an auxiliary force generating means is attached to the other end thereof. This structure makes it possible to prevent an overflow during the initial influx of water and to enhance the ability of the door body to follow the water level when the door body begins to lower. This structure additionally makes it possible to mitigate a shock which occurs when raising of the door body is completed and when lowering of the door body is completed.

Abstract: To prevent a door body from shaking significantly when it rises. A floating body flap gate is provided which is disposed on a roadway surface in an opening; and causes a door body to rise to block the opening when water is trying to flow in from the opening by using a water pressure of the water which is trying to flow in and a buoyancy of the door body. The door body is formed with three door body blocks, which are separated in the vertical direction. These door body blocks which are separated in the vertical direction, are connected by rotation mechanisms for rotation at a specified angle within a vertical plane in a direction in which the water is trying to flow in from the opening. The door body is not subject to significant shaking, regardless of the water level at which the water tries to flow in from the opening.

Abstract: The present invention provides a floating flap gap which has a door body with a forward end which is able to swing upwards, in a direction in which the water flows into an opening or at an access way, around a base end thereof serving as a fulcrum. The door body is attached to one end of a wire rope, and an auxiliary force generating means is attached to the other end thereof. This structure makes it possible to prevent an overflow during the initial influx of water and to enhance the ability of the door body to follow the water level when the door body begins to lower. This structure additionally makes it possible to mitigate a shock which occurs when raising of the door body is completed and when lowering of the door body is completed.

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 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.