JPH02279815A - Automatic gate for fishway - Google Patents

Abstract

PURPOSE:To automate a fishway gate by providing float chambers to a side wall section of the end of the gate crossing the fishway, connecting an interior decorated float and gate with an arm, and controlling the run-off of the fishway by the gate interlocking with the float. CONSTITUTION:Float chambers 14 are provided to both sides of a gate 13 provided together with each impervious wall 12, and the right and left float chambers 14 and 14 are connected with connection pipes 15. After that, each float chamber 14 is connected with the float chamber 14 of the lower stream and an outflow pipe 17, and a notched weir 18 is bored into a wall separating a section of the direct lower stream of the gate 13 from the float chamber 14. Then, a float 16 and the section of the direct lower stream of the gate 13 are connected with a water conduit 27. When the water level of a reservoir rises, the depth of an overflow from the notched weir 18 reaches a specific value and the water level inside the float chamber 14 rises, and the gate 13 is interlocked to reduce an overflow. According to the constitution, the run-off can be easily controlled to automate the gate 13.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is directed to a fishway installed in a dam or weir for fish to migrate upstream, by adjusting the gate provided in the fishway in response to changes in the water level of the upstream water storage level. Move up and down.

This invention relates to an automatic fishway gate for keeping the depth of water flowing over the gate constant.

(Prior art) Conventionally, when the water level difference between the upstream and downstream sides of a weir becomes large, it becomes difficult for fish to swim upstream.
Some have fish ladders attached to the weirs. in this case,
As shown in FIG. 8, a plurality of roller games (1) are provided in the fishway, each of which is provided with an elevator 2, so that the water level can be lowered one by one. In addition, in the one shown in FIG. 9, a so-called overturning weir 4 that rotates around a shaft 3 fixed to the river bed is installed, each of which is connected by a link member 5, and a levying means 6 such as a winch or a hydraulic device is installed. is connected to. These are designed to manually operate the elevator 2 or the undulating means 6 every time the upstream water level changes.

(Problem to be solved by the invention) In reality, the water level of a reservoir constantly fluctuates according to changes in the inflow and outflow, and the fluctuations are particularly severe in reservoirs whose area is small compared to the flow rate. , the flow rate of fish passages is often too high or too low, which impedes fish migration. For this reason, it was necessary to have an operator stationed at all times to adjust the height of the gate of Fish Passage 5. In addition, fish ladder gates are usually limited by the height at which fish can jump, so they usually have a very large number of stages, and the equipment costs are high because the power for these many gates must be provided.

In order to comprehensively solve the above problems, the present invention aims to provide an automatic fishway gate that can adjust the height of the gate by utilizing natural forces.

(Means for Solving the Problems) In order to achieve the above object, the configuration of the present invention is such that, in a fishway formed by partitioning a waterway inclined in the downstream direction at appropriate intervals, a side wall at an end of a gate that crosses the fishway is provided. A float chamber with a float arranged in the section is provided, a cutout weir is provided on the common side wall of the float chamber and the section immediately downstream of the gate, and the lower part of the float chamber is provided with a float chamber downstream of the float chamber or the section immediately downstream of the gate. The present invention is characterized in that an outflow pipe communicating with the float is provided, and the float and the gate are connected by a connecting arm.

In addition, when the water level of the reservoir drops, the gate, which no longer needs to be dammed, can be lowered deep into the water so that it does not interfere with the fish's migration upstream. Use a means to direct water to the area immediately downstream.

(Function) Since the present invention is constructed as described above, if the water level in the section immediately downstream of the gate becomes slightly lower than a predetermined height, the amount of water flowing into the float chamber will decrease, and the water level in the float chamber will decrease. As the water level becomes lower, the gate blocking the most upstream part descends, the flow rate increases, and the water level in the section immediately downstream of the gate is restored, and the gate becomes stationary. Thereafter, if the water level in the reservoir decreases and becomes equal to the predetermined water level in the section immediately downstream of the gate, and the gate no longer needs to be dammed, the gate will move downward due to the above-mentioned action.

Furthermore, since water is introduced into the upper part of the float, the water comes in as the float descends, so the buoyant force acting on it does not increase as the float descends, so the gate sinks deep into the water and prevents fish from passing through. It won't get in the way.

In this way, when the water level of the reservoir decreases, the gates are lowered one after another, starting from the upstream gate, and the depth of the water that overflows the gates in the fishway is always maintained constant, creating the best conditions for fish to migrate upstream. is maintained. Conversely, if the water level in the reservoir rises, the gates will rise one after another, starting with the downstream gate, to maintain a constant depth of water overflowing the gate and maintain the best conditions for fish to migrate upstream. dripping

(Example) An example of the present invention will be described based on FIGS. 1 to 7.

As shown in FIG. 7, when a dam 7 is constructed within a river, water flow is dammed and a reservoir 8 is formed.

A fishway 10 consisting of a stepped waterway partitioned by partition walls is provided along a river 9 downstream from the reservoir 8 and the dam.

Regarding the reservoir 8, as shown in Fig. 6, a minimum water level, L, and a permanent full water level, H, L, are set. A plurality of water shielding walls 12 are fixed at appropriate intervals in the upstream portion, and water shielding walls 12 are fixed at appropriate intervals in the upper part of the flow path. It is divided into multiple stages by installing a gate 13 that can be raised and lowered in contact with the water wall 12.

FIG. 1 is a plan view of the fishway, in which float chambers 14 are provided on both sides of a gate 13 attached to each impermeable wall 12, and the left and right float chambers 14.14 are connected to each other with a sufficiently large cross section. The pipes 15 communicate with each other. A float 16 is housed in the float chamber 14 with a gap therebetween as small as possible. Of course, the float chamber 14 and the float 1B are symmetrical with respect to the gate 13. Each float chamber 14 is connected to the float chamber 14 downstream thereof.
The outflow pipe 17 for the most downstream float chamber 14a is connected to the most downstream partition wall 11.
It is communicated with the compartment downstream of a.゛The outflow pipe 17
has a sufficiently large cross section, but the outflow r3tea at its downstream end is narrowed to a sufficiently small size.

In addition, a cutout weir 18 is bored in the wall separating the section immediately downstream of the fishway 13 and the float chamber 14, and its base ring is sufficiently long and the height is set at a predetermined water level in that section of the fishway. The screen 18 is installed at the top of the weir 18.
A dust-proof and wave-proof wall 20, which is open at the bottom, is attached to the wall surface on which the notched weir 1B is provided, surrounding the notched weir 18 with an appropriate space.

Details of the side wall of the fishway gate are shown in Figures 2 and 3. As mentioned above, a cutout weir 18 is bored in the side wall of the section immediately downstream of the gate 13, and the gate 13 and the impermeable wall are connected to each other. 12
A water-stop rubber 21 is attached between the dust-proof and wave-proof wall 20 and the screen 18 to block water flow. Also,
Door grooves 22 are vertically provided on both sides of the gate 13 (one side omitted), and liner plates 23 made of thick plates are attached to both sides of the door groove 22.
A wheel 24 fixed along the side edge of the gate 13 is fitted, and the edge of the liner plate 23 and the edge of the wheel 24 come into contact to regulate the position of the gate 13.

As shown in FIG. 3, the float 1B has a suspension frame 25 fixed to its upper end, from which the gate 13 is suspended.

Further, as shown in FIG. 4, the float IB consists of an upper water introduction chamber 18a and a lower sealed chamber 18b, and most of the float IB is occupied by the sealed chamber 18b. Upper water introduction chamber 1
A vent hole 28 is provided at the upper end of the water guide chamber H1a, one end of the water guide pipe 27 is opened at the lower end of the water guide chamber H1a, and the other end is opened into a section immediately downstream of the gate 13. A screen 28 is provided at the opening of the water conduit 27. Water pipe 27 route.

It vertically penetrates the sealed chamber 111b, extends from below the flow 1B, is bent via a bendable joint, and is bent at a right angle at the bottom of the float chamber 14 to connect the float chamber 14 and the gate 13. Pass through the wall that separates you and enter Gate 13.
It is connected to the downstream compartment. The height of the lower end of the water guide chamber 18a of the flow) 1B is made sufficiently low so that the gate 13 remains underwater even when it is in its highest raised state.

The size of the sealed chamber t6b of the float 16 is such that the water level in the water guide chamber tea is equal to the predetermined water level in the downstream compartment of the float chamber! The water level in 4 is the water level above and the outflow pipe 17
The float chamber on the downstream side opens! The predetermined water level in section 4 is at the intermediate height (gate 13, flow)
A series of devices consisting of 1B and suspension frame 25 is defined in a balanced manner. At this time, there is almost no overflow to the weir 18, and the planar area of the float 1B is equal to that of the float chamber! The gate 13 is made large enough so that when the water level at No. 4 reaches the water level downstream of the gate 13, the gate 13 rises, and when the water level reaches the water level in the downstream compartment where the outflow pipe 17 is open, the gate 13 descends.

In addition, as shown in FIG. 5, the upper end of the water-shielding wall 12.

A pair of stoppers 29 on the left and right are fixed to protrude toward the gate, and a stopper 30 is fixed near the lower end of the side surface of the corresponding gate 13. Also, the partition wall 11 and the water-blocking wall! A mud draining port 31 of an appropriate size is bored near the lower end of 2. As shown in FIG. 6, an emergency cutoff gate 32 is provided at the upstream end of the fishway to completely block the water flow. In addition, in this FIG. 5, since the float chamber 14 is provided in a ready-made waterway, the side wall protrudes, but it is versatile.

Next, the effect will be explained.

When the water level of the reservoir 8 is lower than the lowest water level, there is no water in each float chamber 14 and all the gates 13 are at the lower limit position, lower than the water-shielding wall 12. For this reason, reservoir 8
Even if the water level is at the lowest level, L, it will not interfere with the communication of running water.

When the water level in the reservoir 8 rises and the overflow depth from the most downstream gate 13, that is, the weir 1B of gate A shown in FIG. 5, reaches a predetermined value, the water level in the float chamber 14 of gate A increases. is equal to the water level in that section of Fishway C, and since the planar area of the float 1B is sufficiently large, the gate A rises in conjunction with the float 1B, and the overflow above the gate A is reduced. As mentioned above, the float chamber 14 and the float 1B
Since the gap between the gates is made as small as possible, when the gate A rises very slightly, the water level in the float chamber 14 decreases and the acting force acting on the float 1B disappears. The percussion movement is extremely small and the flow rate remains constant. After repeating this operation and gate A rising to the upper limit position, when the water level of reservoir 8 rises further, gate B on the upstream side rises in the same way, and the flow rate of the fishway is kept constant. Ru. If the water level of the reservoir 8 always reaches the full water level H, L, it goes without saying that all the games 13 will rise to their upper limit positions.

By the way, fishway game) 13 is characterized by a large number of fish ladders, and in some cases the water level in that section is low due to various reasons such as the water stop rubber 21 of the downstream gate 13 being damaged.
That's why we use Kakukuchi Weir! Float chamber 14 with no inflow from 8
However, due to the outflow tube 7, the float chamber 14 tends to reach a height intermediate between the water levels of the float chambers 14 upstream and downstream thereof, that is, the water level of the float chamber 14 concerned. Therefore, if the water level in the relevant section of the fishway is low due to the above circumstances, it will be called Kakuchi Weir! Outflow occurs from 8, but as mentioned above, the forward ring of the weir 1B is sufficiently long and the cross section of the outlet is sufficiently small! The overflow depth of the outflow is extremely small, so the water level in the float chamber 14 is maintained normally.

A situation in which the gate 13 is lowered due to the upper limit position does not occur.

Next, the effect when the water level of the reservoir 8 decreases will be explained.

When the water level in the reservoir 8 drops slightly, the amount of inflow from the cutout weir 18 of the most upstream gate 13, which had been operating in a partially or completely raised state, decreases, and the water level in the float chamber 14 decreases. As the water level decreases, the water level (13) falls, the overflow increases, and the flow rate of the fishway is maintained at a constant level. In this way, when the water level in the reservoir 8 becomes lower than the predetermined water level in the section immediately downstream of the activated gate 13,
No matter how much the gate 13 is lowered, the water level in the compartment and, by extension, the water level in the float chamber 14 will not rise. While sucking water into Eia) 13 is deeply submerged in the water and maintains the lower limit position, so the useless gate t3 does not get in the way of the fish coming upstream, and it descends like this. It goes without saying that the water level in the fishway inside the fishway will be lower than during the above-mentioned rise, but since the overflow water depth itself has been made extremely small as mentioned above, this difference is practically irrelevant.

Next, consider safety issues. As mentioned above, since the overflow water depth is extremely small, it is conceivable that water may not flow into the float chamber 14 from the weir 18 due to various circumstances. Now, in Fig. 5, if gate B on the upstream side is normal and water does not flow into the float chamber 14 from the cutout weir 18 of gate A on the downstream side, when gate B further descends, the float As the water level in chamber 14 decreases, the water level in gate A's float chamber 14 decreases, and if gate A further falls under the influence of this, there is a risk of flooding within the fishway. The water level in the float chamber 14 of Game) A decreases only to the water level in the compartment immediately downstream of Game) A, so the water level in the float chamber 14 of Game) A falls to a height midway between the water level in this compartment and the water level downstream of it. Therefore, no accident will occur because the water level will only drop to the level at which A) is in equilibrium.

Next, garbage disposal will be explained. Since the dust-proof and breakwater wall 20 is opened downwards, the dust adhering to the screen 19 provided in the cutout weir 18 can be removed by pushing it out from above, or by lowering the emergency shut-off door 32 to stop the water flow in the fishway. mud mouth 3
Water drains from the opening, the water level drops, and the garbage also moves downwards and is flushed away through the opening. In addition, the outlet 17 at the downstream end of the second outlet pipe 17
A is narrowly squeezed, but since the water that originally passed through the screen 19 is soaked in it, it is unlikely to become blocked, but if it becomes blocked, it protrudes into a wide area outside the float chamber 14, so it should be removed and cleaned. be able to. In this case, the emergency shutoff door 32 may be lowered, and the screen 2B at the entrance of the water pipe 27 can also be cleaned. Note that even if the screen 28 at the entrance of the water pipe 27 is blocked, if the water level in the reservoir 8 rises, which could lead to a serious accident, the float 16
Since it is on the exit side where the water inside is discharged, it is not affected as much.

(Effects of the Invention) Since the present invention is constructed as described above, the flow rate of the fishway can be easily adjusted by a gate linked to a float, and can be operated at a low cost and without any power, regardless of the water level of the reservoir. , it is possible to follow this, and it is possible to easily bring the fishway into the best overflow condition. Furthermore, due to the simple configuration using floats, gate failures are less likely to occur.

[Brief explanation of drawings]

FIG. 1 is a plan view of the main part of the fishway according to the embodiment of the present invention, FIG. 2 is a plan view of the side wall near the gate in the embodiment, FIGS. FIG. 4 is a sectional view showing the structure of a float and a float chamber in the embodiment. FIG. 5 is a longitudinal cross-sectional view of the main part of the fishway of the embodiment. Figure 6 is a cross-sectional view of a dam and a fishway attached to the example, Figure 7 is a plan view of a dam and a fishway attached to the example, and Figure 8 is a cross-sectional view of a gate used in a conventional fishway. , FIG. 9 is a sectional view of another gate used in a conventional fishway. 13... Gate 14.14a... Float chamber 1B... Float 17... Outlet pipe 1B... Notch weir 25... ...Connection arm

Claims (1)

[Claims] (1) In a fishway formed by partitioning a waterway sloping in the downstream direction at appropriate intervals, a float chamber with a float arranged on the side wall of the end of the gate that crosses the fishway is provided, and a section immediately downstream of the float chamber and the gate is provided. A cutout weir is installed on the common side wall with the
An automatic fishway gate characterized in that an outflow pipe communicating with a downstream float chamber or the next downstream section is provided in a lower part of the float chamber, and the float and the gate are connected by a connecting arm.