JPS6219696Y2 - - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a fish ladder.

If there is a head difference in the river, a fish ladder is constructed by creating a stepped waterway with a width of 2 to 6 m and a slope of 1/10 to 1/15 to allow passage through the river. The overflow depth of the stepped waterway is generally 0.15m to 0.25m, and it is said that the optimum difference between steps is about 0.3m.

Now, since conventional fishways are generally made of fixed staircases made of concrete, they have the following problems.

(b) Decrease the cross-sectional area of the river and reduce the river's water flow capacity during floods.

(b) Water flows through the fishway only when there is sufficient river water, and it does not function as a fishway during the dry season. Also, it is difficult to secure the optimum overflow water depth.

The present invention solves the above problems. That is, the fishway of the present invention has a plurality of flexible membrane undulating weirs with different weir heights spaced apart in the flow direction of the river, and the weir heights are changed from downstream to upstream in the direction across the river. The weirs are installed so that the height gradually increases, and the water overflows from the top of the weir to allow fish to pass through.The plurality of undulating weirs made of flexible membranes are all connected with weir piping, and 1. A set of upstream water level detectors, a fluid supply device to the weir, a fluid discharge valve in the weir,
A weir internal pressure detector and a control device that connects these using electric signals are installed. When the upstream water level increases, fluid is injected into all weirs from one point in the all weir communication pipes, and the weir height of all weirs is adjusted simultaneously. If the water level rises and the upstream water level falls, the fluid in all weirs is discharged from one point in the weir communication pipe, and the weir height of all weirs is simultaneously lowered, thereby constantly preventing overflow from the top of the weir. It is characterized by ensuring that

An explanation will be given below with reference to the illustrative drawings.

As shown in Fig. 1, the present invention consists of flexible membrane undulating weirs 1, 1', 1", 1 etc., and all the weirs are connected to the piping.

During dry periods, the overflow water volume is ensured by reducing the internal pressure of the weir and lowering the weir height, as shown in Figure 2, and when the water rises, the overflow water volume is maintained at a predetermined level by increasing the weir internal pressure and raising the weir height. Make it.

As mentioned above, except during times of abnormal drought, water can always flow through the fishway as described below.

In Figures 1 and 2, 2 is a fishway and 3 is an inlet and drain (air) pipe for communication piping, and the flexible membrane undulating weirs 1, 1', 1'', 1, etc. are already known. A flexible membrane envelope (bag-like body) forming a weir body is attached to at least the river bed in a direction transverse to the flow, and water, air, or both are supplied from an inlet/drainage (air) pipe communicating inside the envelope. It is designed to inflate and stand up by feeding equal fluid, or to contract and fall down by discharging fluid (see, for example, Japanese Patent Publications No. 11702-1970 and Japanese Patent Publication No. 2371-1971).

Figure 3 is a front view of the river seen from the downstream side to the upstream side in Figure 1, where 2 is a fishway, 4 is a river bed, 6 is a weir, 7 is a river bank slope, and 7 is a fishway partition. It's a wall.

The concrete implementation of the above will be carried out as follows.

Piping will be provided that communicates with each weir.

A common fluid supply device and a weir fluid discharge valve will be provided for each weir.

A common weir internal pressure sensor will be provided for each weir.

An upstream water level detector will be installed for each weir.

, ~ fluid supply device, weir fluid discharge valve,
A control device is provided that is connected to the water level detector and internal pressure detector by electrical signals. Since the weir height is determined by the relationship between the water level and internal pressure, this relationship should be determined in advance through calculations and experiments, and input into the controller's memory.

A diagram of the above combination is shown in FIG. The above devices are installed at one end of the piping that communicates with each weir. Figure 4 shows the water expansion type. 1 in Figure 4 is a weir;
2 is a fish ladder, 3 is an inlet/drainage pipe, 4 is a river bed, 8 is a supply/drainage pump, 9 is a siphon pipe, 10 is a valve, 11 is a water level detector, 12 is an internal pressure detector, 13
Reference numeral 14 indicates a control device, and 14 indicates wiring for supplying electric signals. Note that P ₁ , P ₂ ... are the internal pressures of the weir set to correspond to each water level range. Further, the siphon pipe 9 is a safety device for preventing overpressure in the weir internal pressure, and when the water supply from the pump 8 is excessive, the excess water is discharged from the siphon pipe 9.

In the above case, the weir is toppled as follows. The upstream water level is checked with the water level detector 11, and the internal pressure corresponding to the set water level is set. If the water level falls and falls within another set water level range, the drainage pump will operate to correspond to this water level.

The expansion of the weir is carried out as follows. If the upstream water level rises and falls within a set water level range different from the current level, the water supply pump is operated to bring the internal pressure corresponding to this water level. Stop the water pump when the set internal pressure is reached. All of these are automatically performed by the control device.

The present invention as described above has the following advantages.

By completely collapsing the undulating weir during floods, the river's water flow capacity will not be reduced.

It is highly effective as a fish ladder because it can easily maintain a constant overflow depth even during dry and flood seasons.

In the present invention, it has been explained that all the weirs are expanded and collapsed at the same time due to the increase and decrease of the upstream water level by means of communicating piping, but it is not necessarily the whole weir, but may be partial.

[Brief explanation of the drawing]

Figure 1 is a diagram of the fishway according to the present invention taken in the flow direction during normal water flow, Figure 2 is a diagram taken in the flow direction of the fishway of the present invention during drought, and Figure 3 is the fishway of Figure 1. FIG. 4 is a front view viewed from the downstream side to the upstream side, and FIG. 4 is an explanatory view of a means for expanding and collapsing the weir of the fish passage according to the present invention by increasing or decreasing the upstream water level. 1, 1', 1'', 1...flexible membrane undulating weir, 2
... Fishway, 3 ... Water supply and drainage (air) pipe, 4 ... River bed, 5 ... Weir, 6 ... Riverbank slope, 7 ... Partition wall for fishway, 8 ... Water supply and drainage pump, 9 ... Siphon Pipe, 10...Valve, 11...Water level detector, 12
...Internal pressure detector, 13...Control device, 14...Wiring.

Claims (1)

[Scope of utility model registration request] A plurality of undulating weirs made of flexible membranes with different weir heights are installed in the river at intervals in the flow direction, and the weir heights gradually increase from downstream to upstream in the direction across the river. The water is allowed to overflow from the top of the weir to allow fish to pass through, and the plurality of flexible membrane undulating weirs are connected to all weirs, with a set of upstream water level detectors, A fluid supply device, a fluid discharge valve inside the weir, a weir internal pressure detector, and a control device that connects these using electrical signals are installed.If the upstream water level increases, the fluid is supplied to the inside of the entire weir from one point in the weir communication pipe. Fluid is injected to raise the height of all weirs at the same time, and when the upstream water level decreases, the fluid in all weirs is discharged from one point in the weir communication pipe to lower the weir height of all weirs at the same time. A fishway that is characterized by always ensuring overflow from the top of the weir.