JPS6260522B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device utilizing the siphon phenomenon in a water-expandable flexible membrane undulating weir, that is, an improvement to a siphon device.

Recently, undulating weirs made of flexible membranes have been used for regulating river water levels. This flexible membrane undulating weir has a flexible membrane envelope (bag-like body) made of rubber-coated cloth, etc., which forms the weir body, attached to at least the river bed in the direction across the river, and inside the envelope. A fluid such as air, water, or both is sent from a communicating inlet/exhaust (water) pipe to cause the enclosure to expand and stand up, or to discharge fluid from inside the envelope to cause the enclosure to contract and fall down (for example,
11702, Special Publication No. 44-2371).

Among these types of undulating weirs, the siphon tube 3 is currently used as a safety device for water-inflatable flexible membrane undulating weirs. That is, as shown in Fig. 1, when the normal upstream water level 4 reaches the collapsed water level 9, the upstream water level detection tube 1
At step 7, the water level in the tank 16 communicating with the upstream of the river rises, the float 15 floats up, the mechanical valve 11 is opened, air is sent from the compressed air tank 13 to the cylinder valve 5, and the cylinder valve 5
is opened and the water inside the weir is discharged, but if
If a malfunction occurs in these devices and the cylinder valve 5 is not opened, if the water level (water pressure) in the weir body exceeds the height of the siphon pipe 3, a siphon phenomenon will occur and the water in the weir body will be discharged. . (For example, see Japanese Patent Publication No. 57-53485.) However, when the rise in water level (water pressure) inside the weir is minute, the siphon phenomenon does not occur as shown in Figure 2 (if the pipe diameter is small, the siphon phenomenon does not occur). A water column is formed, but in order to keep the collapse time within a certain range, a certain amount of pipe diameter is required (for example, 100A),
There is a risk that the weir will not collapse when it should, causing flooding. In other words, there is a risk that the siphon tube as a safety device may not work. In FIG. 1, numeral 1 indicates a flexible membrane envelope forming the weir body, and numeral 2 indicates a river bed.

In addition, an example of using multiple pipes with different diameters as a siphon device for generally draining liquid is shown in Utility Model Application Publication No. 54-74310, but this is designed to continuously drain the liquid from the container. This was intended for the purpose, but did not take drainage time into account. Therefore, the siphon phenomenon, which is effective against changes in the water level (water pressure) within the weir body, does not occur, making it unsuitable as a safety device for water-expandable flexible membrane undulating weirs due to the risk of flooding.

In view of this, the present invention has been developed to provide a undulating weir made of a water-expandable flexible membrane that collapses in a time close to a predetermined value and has a low risk of causing flooding, and has been developed with respect to a siphon device used in the lodging device. It is something that

The present invention will be explained in detail below with reference to the illustrative drawings. However, it is not limited to this.

FIG. 3 is an explanatory perspective view of the siphon tube used in the present invention. That is, as shown in the figure, by providing a plurality of thin tubes 7 inside one siphon tube 3, the cross section of the siphon tube is divided into a plurality of sections. In addition, both ends of the thin tube 7 have a siphon height of 8.
The following is sufficient. If the water level rises from (A) to (B), the siphon in the small diameter pipe below (B) will work and the liquid will be continuously discharged. When the water level further rises from (B) to (C), the siphon in the small diameter pipe below (C) works. Furthermore, even if the water level drops from (C) to (A), the siphon works in the small diameter pipe below (C) and liquid is continuously discharged.

On the other hand, in a water-inflatable undulating weir made of flexible membrane, the water level (water pressure) inside the weir changes as the flow rate of the river changes, so the water level inside the weir rises to (C) and then decreases as described above. That is quite possible. Even in this case, the liquid is discharged from the small diameter pipe below (C), so
The weir collapses in a time close to the predetermined value, reducing the risk of flooding.

As described above, according to the present invention, it is possible to prevent the siphon device used in the lodging device of a water-expandable flexible membrane undulating weir from not working, and the risk of flooding can be reduced.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of a flexible membrane undulating weir that utilizes the siphon phenomenon (the undulating weir is cut in the direction across the river flow), and Figure 2 shows the water level inside the weir in the undulating weir shown in Figure 1. FIG. 3 is a diagram illustrating that the siphon phenomenon may not occur if the increase in water pressure is minute, and FIG. 3 is a perspective view of a siphon tube used in the present invention. 1...Flexible membrane envelope forming the weir body, 2...
...river bed, 3...siphon pipe, 4...upstream water level,
5... Valve, 6... Water as pressure medium, 7... Thin pipe, 8... Siphon height, 9... Lodging water level,
10... Water injection pump, 11, 12... Mechanical valve, 13... Compressed air tank, 14... Compressor, 15... Float, 16... Tank, 17... Upstream water level detection pipe, 18... Drain pipe .

Claims (1)

[Claims] 1. A water-expandable siphon tube used in a lodging device for a water-expandable undulating weir made of a water-expandable flexible membrane, characterized in that the cross-section of the siphon tube is divided into a plurality of parts by providing a plurality of thin tubes inside the siphon tube. A siphon device used in the lodging device of flexible membrane undulating weirs.