JPH0369712A - Automatic reverse flow preventing device utilizing buoyancy - Google Patents

Abstract

PURPOSE:To automatically prevent the generation of a reverse flow by a method wherein a floating body is mechanically coupled to a partition member so that the upper end of the partition member is vertically moved according to the vertical movement of the floating body. CONSTITUTION:A moving body 12 provided at its interior with an air reservoir is formed with a plate part 14 and a floating body wall 16, and the moving hody 12 is installed across a channel. A bellows type sideways expansion and contraction part 18 is arranged between a gate type stay part 10 and the moving body 12 located in the channel. When salt water on the sea side is raised with the progress of high water, the moving body 12 is raised by means of buoyancy generated due to accumulation of air, and the reverse flow of salt water to the river side is prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a structure that combines a partition member and a floating body that crosses a waterway, and more specifically, the present invention relates to a structure in which the upper end of the partition member is connected to the water level on the downstream side. This relates to a device that automatically moves up and down in response to changes. Although not particularly limited, this technology can be applied to tide stop weirs and the like that can be installed near river mouths to prevent saltwater from flowing up and to maintain a constant warm water level.

[Prior Art] Hereinafter, the case of a tidal weir, which is the most effective field of application of the present invention, will be described as an example. In the ground within the levee near the river mouth, the harmful effects of salt water intrusion resulting from the salinization of groundwater have become an important issue. In particular, there are many cases where river water cannot be used due to issues such as water rights, and underground water is pumped up as a water source for tap water, agricultural water, industrial water, etc., which promotes salinization. Digging deep into the riverbed to widen the riverbed expands the range of saltwater intrusion, making it more likely that the above-mentioned problems will occur, and in practice this often poses a hindrance to river improvement. It has been proposed to impound water and use the water pressure to supply fresh water to the levee area, as well as to prevent salt water from flowing up.

By the way, there are two types of weirs: movable weirs that can adjust the water level and amount, and fixed weirs that cannot be adjusted. Furthermore, movable weirs, which are often installed side by side, have some kind of drive mechanism, and are generally operated by a motor or the like by supplying energy such as electric power.

[Problems to be solved by the invention] A tidal weir installed near the river mouth must: ■ be able to store water at a state close to a constant water level on the river side; It is required to perform the following functions: - to allow salt water to flow, and - to prevent salt water from entering the river side at any time.

If the warm water level on the river side is always higher than the high tide water level on the sea side, a conventional fixed weir can be installed. On the other hand, if the range of tidal fluctuation is large and the water level at high tide is higher than the warm water level on the river side, it will be necessary to adjust the weir height at low tide. If this were to be done using conventional technology, it would be necessary to create an automatically movable weir using a power source.

In other words, the tide level on the sea side is measured by some kind of sensor, and the height of the weir is adjusted by driving a motor or the like based on that measurement. Then what about the mechanism? It will be JIM, and a power source will also be required.

An object of the present invention is to solve the problems of the prior art as described above, to automatically adjust the height according to the water level on the downstream side without requiring special power, and to adjust the height of the water level on the upstream side. To provide an automatic backflow prevention device that prevents water from flowing back from the downstream side to the upstream side regardless of the situation.

[Means for Solving the Problems] The present invention, which can solve the above-mentioned technical problems, provides an underwater/aquatic structure in which the substantial height of a partition member can be automatically varied using buoyancy. It is. That is, the present invention
A partition member that is installed across a waterway and whose upper end is movable in the vertical direction while its lower end is located at the bottom of the waterway; and a partition member that is located downstream of the partition member and moves up and down in accordance with changes in the water level on the downstream side. This is an automatic backflow prevention device using buoyancy, which is equipped with a floating body and mechanically connects the floating body and the partition member so that the upper end of the partition member also moves in the vertical direction according to the vertical movement of the floating body.

Here, the partition member and the floating body may be integrated or may be separate bodies. The partition member may be a rigid body, a bellows-like elastic structure, or a sheet-like flexible member. In any case, the cross-sectional area across the waterway can be substantially varied.

[Function] The waterway is partitioned by the partition member, and water can be stored by the height of the partition. If the water level downstream is low,
Correspondingly, since the position of the floating body is lowered, the upper end position of the partition member is also lowered.

When the water on the upstream side rises above the partition member, it overflows and flows downstream.

As the water level on the downstream side rises, the floating body rises, and the upper end of the partition member moves upward while the lower end remains located at the bottom of the waterway. Therefore, even if the substantial partition area increases and the water level on the downstream side becomes higher than the water level on the upstream side, the water will not flow backward from the downstream side to the upstream side because it is partitioned by the partition member.

When this device is installed at the river mouth, water from the upstream river side can overflow the partition member and flow downstream to the sea side at low tide, but at high tide, the partition member prevents seawater from flowing backwards and prevents saltwater from running up. .

[Embodiment] FIG. 1 is an explanatory diagram showing an embodiment of the automatic backflow prevention device according to the present invention, and FIGS. 2A and 2B are explanatory diagrams of its operation. In this embodiment, a gate-shaped support lO is provided in the waterway, and the movable body 12 is installed across the waterway and is swingably supported at both ends of its lower part. The movable body 12 has a flat plate part 14 serving as a partition member, and a floating body wall 16 that projects toward the downstream side from the upper end side and also surrounds the sides, and has a structure in which the inside becomes an air reservoir 20. . This air pocket becomes the floating body. A bellows-type lateral expandable section 18 is provided between both sides of the movable body 12 and the support section 10 to regulate the waterway. In the same figure, the left side of the drawing is the river side,
The right side of the drawing is the sea side.

Buoyancy is used to move the movable body 12 up and down.

As shown in FIG. 2, at low tide, river water floods the river side at a constant water level, and river water that exceeds the height of the movable body 12 overflows it and flows to the sea side.

The air pocket structure prevents the movable body 12 from sinking beyond a certain depth, and this height is determined by the floating body wall 16.

When the salt water on the sea side rises with high tide, movable body 1
2 also rises due to the buoyancy caused by the air pocket 20.
(See Figure 2 B), if the dimensions are determined in advance so that it does not exceed the upper edge of the movable body 12 at high tide, salt water can
It will not flow back to the river side beyond 2. That is, in this case, the shape of the movable body 12 is determined in consideration of the maximum high tide and wave height. When the movable body 12 rises, the warm water level on the river side rises in accordance with the river flow rate, but even if it rises at a faster rate than the rise of salt water, the river water may overflow, but the salt water will not rise. It does not penetrate beyond the movable body 12.

This is because the weir always maintains a balance between the hot water pressure on the river side and the salt water pressure on the sea side, and the structure is such that the upper end of the movable body 12 is always higher than the salt water level. .

In this way, river water can always be stored above a certain level near the river mouth. The warm water level of river water can be adjusted by adjusting the amount of air in the air reservoir 20. In this embodiment, the flat plate part 14 serving as a partition member has a cross-sectional shape that protrudes toward the downstream side from the upper end side and is further bent from the tip toward the lower end. It is preferable to further bend the tip in this way because it can prevent air from escaping from the air pocket 20 due to changes in the sea level due to waves, etc. However, depending on the installation situation and sea side conditions, As shown, there is a shape without a bent part at the tip,
It may also be in a completely sealed shape as shown in Figure B.
Of course, the shape is not limited to these and can be modified as appropriate.

FIG. 4 shows another embodiment of the invention.

The partition member 22 has a bellows-like expandable structure, its lower end is fixed to the riverbed, and its upper end is held by a support 26 by a swinging arm 24. In this case, the t-operation point 24a is exposed above the water surface, making maintenance easier. The upper end of the partition member 22 extends toward the upstream side, and a floating body 28 is attached to the tip. This floating body 28 is mechanically connected by a parallelogram-shaped link mechanism 30 including the swing arm 24, and can move up and down without changing the direction of the floating body 28.

The basic operation is the same as in the previous embodiment. As shown in FIG. 4A, at low tide, the floating body 28 is lowered, and the water level on the river side has a water level equal to the height of the partition member 22, and the amount exceeding this level overflows to the sea side. At high tide, Figure B
As shown in FIG. 2, buoyancy is applied to the floating body 28, which causes the bellows-shaped partition member 22 to expand and dam the seawater from flowing up.

FIG. 5 shows a modification of the embodiment shown in FIG.

A bellows-shaped partition member 22 is provided on the downstream side (sea side) and is configured to extend toward the sea side at high tide.Since the basic idea is the same as the embodiment shown in FIG. The same reference numerals are given to the parts, and the explanation thereof will be omitted.The shape of the floating body is semi-cylindrical, but there is no particular restriction on this.

6A and 6B show still another embodiment of the present invention.

Here, a waterproof sheet 40 is used as the partition member. One end of the waterproof sheet 40 is fixed to a cylindrical floating body 42,
Wrap it around one part of it and fix the other end to the riverbed. floating body 42
A wire 44 is hung at the center of both ends, and the wire 4
4 is connected to a weight 50 through a pulley 48 at the upper end of the column 46. The floating body 42 is located on the downstream side, and has a structure that allows it to move up and down while rotating. As shown in FIG.
It overflows and flows towards the sea. As the seawater level rises, the floating body 42 rotates in the direction of the arrow and rises, and the waterproof sheet 40 that was wrapped around it unravels and rises along the pillars 46 (see Figure B).This prevents the backflow of seawater at high tide. It can be prevented.

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to only such a configuration.The shape of the floating body, the shape of the partition member, its expansion/contraction mechanism, etc. can be changed as appropriate depending on the usage conditions etc. Can be changed. The above embodiment is an example of an automatic tidal weir installed near the mouth of an estuary, but it can also be used for other purposes, such as installing it at the entrance of a lagoon to desalinate the lagoon, or for various types of water intake. It can also be used as a gate for equipment, wastewater treatment equipment, etc., even if the water level fluctuates on the downstream side, allowing overflow from the upstream side to the downstream side, but preventing backflow.

[Effects of the Invention] As described above, the present invention is provided across the waterway, and the upper end is movable in the vertical direction while the lower end is located at the bottom of the waterway, so that the water on the upstream side is always kept at the same height. You can store more than that. In addition, the structure mechanically connects the floating body that moves up and down depending on the water level on the downstream side to the partition member, and uses the buoyancy applied to the floating body to move the partition member, so there is no need for a special power source like in the past. It has the advantage of low operating costs. Particularly in the case of a tidal weir installed near an estuary, tidal motion can be used to automatically move the partition member up and down, eliminating the need for human monitoring or operation. Furthermore, since the mechanism is extremely simple, maintenance management is easy. The upstream water level can be adjusted by adjusting the shape of the floating body or the amount of air in the air pocket.

As a result, especially when used as a tidal weir, it is possible to avoid the harmful effects of salinization due to saltwater run-up in the levee land and basin near the river mouth, and river improvement is also possible, so the economic effects are extremely high. big.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing one embodiment of the automatic backflow prevention device according to the present invention, FIGS. 2A and B are explanatory diagrams of its operation, and FIGS. 3A,
B is a sectional view showing another example of the movable body. Figure 4A
, B are explanatory diagrams showing other embodiments of the present invention, FIGS. 5A and B
6A and 6B are explanatory diagrams showing other embodiments of the present invention, and FIGS. 6A and 6B are explanatory diagrams showing other embodiments of the present invention. DESCRIPTION OF SYMBOLS 10... Strut part, 12... Movable body, 14... Flat plate part, 16... Floating body wall, 18... Lateral expansion and contraction part, 20...
... Air pocket, 22 ... Partition member, 40 ... Waterproof sheet.

Claims (1)

[Scope of Claims] 1. A partition member that is provided across the waterway and whose upper end is movable in the vertical direction while the lower end is located at the bottom of the waterway, and which is located downstream of the partition member and responds to changes in water level. Automatic backflow prevention using buoyancy, characterized in that the floating body and the partition member are mechanically connected so that the upper end of the partition member also moves in the vertical direction according to the vertical movement of the floating body. Device. 2. The movable body is made up of a flat plate that serves as a partition member and a floating wall that protrudes downstream from its upper edge and surrounds the sides and serves as an air reservoir inside, which can be swung at both ends of the lower part. 2. The device of claim 1, supported on a. 3. The partition member has a bellows-like expandable structure, is fixed at the lower end and held by a swinging arm at the upper end, and the floating body is connected to the upper part of the partition member by a parallelogram link mechanism including the swinging arm. 2. The device according to claim 1, wherein: