JPH09291520A - Floatable fish path device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fish path device having a slope on which fishes can climb up, and which can follow variation of the level of upstream water. SOLUTION: Water from upstream of a dam is pooled in a recess formed in the river bed just downstream of the dam, and a fish path body 27 composed of a pedestal 26 and a spiral water channel 25 set on the pedestal 26 is floated on the water in the recess. Further, an upstream discharge channel 52 is communicated at its opening with the upper end of the water channel, and the lower end of the channel 25 is merged with a downstream annular water tank 48 surrounding the fish path body 27. The pedestal 26 is formed in its lower part with an expansion and contraction chamber 39 in which water from the upstream side is filled after being adjusted. Due to variation of the level of water, the fish path body 27 floats up and down by the water pressure in the expansion and contraction chamber 39 so that the channel 25 can be communicated with the discharge channel 52 even though the communicating position at the upper end of the channel 25 is high. Accordingly, even though the lower end of the channel 25 is submerged, the merged water surface is flush with the water surface of the annular water tank 48.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION In general, when constructing dams, weirs, etc., it is recommended to secure a waterway for run-up fish, and a plurality of partition walls are provided in the waterway bypassing the fishway to lower the water level sequentially. The fish are designed to be able to go up over the bulkhead. At the place where the upstream water level is stable, the height of the partition wall provided in the waterway is fixed and the structure is simple. In addition, at locations where the upstream water level fluctuates, the height of the upstream partition wall will be adjusted so that the fish can cross it according to the upstream water level. Therefore, the present invention relates to a floating fishway device intended to cope with fluctuations in upstream water level.

[0002]

2. Description of the Related Art Conventionally, some new dams have a fixed staircase-shaped fishway provided on a concrete side wall to secure a waterway for upstream fish. This staircase-shaped fishway is one in which a plurality of partition walls are provided in the water channel to gradually lower the water level according to the water level difference between the reservoir water surface and the downstream water surface. There are few steps due to the partition walls, and if the water level difference from the downstream water surface due to the dam is large, the section of the fishway will be long and a large installation space will be required. If you cannot afford the installation space,
A spiral canal is proposed in which the fishway canal is superposed on the fishway canal. For example, as shown in FIGS. 26 and 27, the spiral fishway device 1 made of concrete forms a spiral water channel that is wound several times along a cylindrical inner wall,
The downstream end of the spiral channel communicates with the downstream channel 2 of the weir,
The upstream end of the spiral water channel is connected to the upstream side of the weir body or the reservoir via the connecting water channel 3.

In addition, a stack-type fishway device (Japanese Patent Application No. 6-
The applicant is presenting it as No. 146871). This spiral shape is arranged horizontally for each side, inclined, and alternately laid horizontally and inclined to circulate.

By the way, these fishway waterways are provided with a plurality of partition walls, and the uppermost partition wall is adjusted to the water level of the reservoir so that the fish can go upstream. Therefore, when the upstream water level changes, at least the height of the uppermost partition wall must be adjusted. The fishway device 4 (see Japanese Patent Application No. 1-288420) shown in FIG. 28 is adapted to cope with fluctuations in the upstream water level. The fishway body 5 of the fishway device 4 can be housed in a recess 6 formed in the riverbed, the downstream end of the fishway body 4 is attached to the peripheral edge of the recess 6 via a main shaft 7, and the fishway body 5 draws an arc on the upstream side. So that it can rotate freely. In the fishway main body 5, a water channel 10 having a partition wall 9 is formed on the upper surface of the hermetically sealed portion 8, an end plate 11 is attached to the upstream end, and a water pressure chamber 12 is formed below the hermetically sealed portion 8. And
The central portion of the end plate 11 is used as a waterway entrance, and the water pressure chamber 1 is provided on the left and right sides.
2 is provided with an inflow port 13 that faces the water channel 2, and a water pressure chamber 12 and an outflow pipe 14 that communicates with the water channel downstream side are provided on the downstream side of the fishway body 5. Therefore, when the fishway main body 5 is placed on the gantry 15, the upstream water level is the lower limit water level, and when the upstream water level increases, the amount of water flowing down from the inflow port 13 increases, and the fishway main body 5 is stored by the water stored in the hydraulic chamber. Ascends and the upstream water channel and the water channel 10 are smoothly connected.

[0005]

In the fishway device 4 described above, when the difference between the upper and lower water levels becomes large, the fishway main body 5
Turns sharply and the slope becomes steep, making it difficult for fish to go up. In addition, although the slope can be made gentle by increasing the length of the water channel, there is a problem that the slope changes due to the water level difference and the slope suitable for run-up fish cannot be maintained.

[0006] It is an object of the present invention to provide a fishway device which makes it easy for a run-up fish to go back even when the upstream water level changes.

[0007]

In order to achieve the above object, the present invention adopts a method in which a fishway device is floated on the surface of the water. The structure is such that a recess is formed in the riverbed just downstream of a weir body that crosses a river. , A vertical axis having a height higher than the upper limit water level of the flowing water discharged from the weir is erected on the bottom surface of the recess, and a pedestal conforming to the horizontal cross-sectional shape of the recess is supported by the vertical axis to be vertically movable. The fishway main body is formed by the pedestal and a spiral water channel extending vertically from this surface and having a slope suitable for fish run-up and descent. A discharge chamber that forms a compression chamber, and is provided with a pipe for inflowing / storing the upstream water of the weir body and an outflow pipe for discharging it to the downstream water channel in the expansion / contraction chamber to communicate with the upper / lower limit water levels of the stored water. The upper end of the spiral water channel is exposed to the water channel, and the upper end of the spiral water channel is opened. The fishway main body is provided with an end plate for closing the lower part of the opening of the discharge waterway while connecting with the discharge waterway, and an interval for fish to swim is located on the outer circumference of the spiral waterway or the outer circumference of the pedestal. It is characterized in that a side wall is formed in the river bed so as to be vacant, and the annular water tank surrounded by the side wall is connected to the downstream side water channel via a partition wall.

In addition, a vertical shaft is provided at the center of the pedestal, and a watertight rubber is provided on the outer periphery of the pedestal at the lower part of the pedestal so as to closely contact the side wall of the recess to form an expansion / contraction chamber isolated from the upper part of the pedestal. The expansion and contraction chamber is formed by fixing the upper end of the expandable cylinder to the lower surface of the pedestal and fixing the lower end to the floor surface of the recess.

The pipe for inflowing and storing the flowing water on the upstream side of the weir body is composed of an inflow pipe adjacent to the upper end of the spiral water passage and connecting the inflowing water tank communicating with the flowing water and the expansion / contraction chamber. The diameter of the inlet pipe swallow portion is larger than the diameter of the outlet pipe.

Further, the shape of the spiral water channel is such that the cross section in the axial direction of the spiral is circular so as to have a constant slope, or the cross section in the axial direction of the spiral is rectangular, and horizontal, inclined, horizontal, and inclined are alternated for each side. It is characterized in that it is arranged so as to be linked to the.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The fishway device according to the present invention floats a waterway for a fishway on the water surface, and further moves the waterway in the vertical direction for position adjustment. For this reason, a recess is formed in the riverbed immediately downstream of the weir body, a vertical axis is erected from the center of the recess, and a fishway main body consisting of a spiral water channel and a pedestal is vertically movable. The spiral canal has a slope suitable for fish run-up and descent.

On the other hand, the discharge channel on the upstream side is provided with an opening having a height width from the upper limit water level to the lower limit water level, and the upper end of the spiral water channel of the fishway main body faces this opening, and by the end plate fixed to the fishway main body, The upper end of the waterway communicates with the upper part of the opening of the discharge waterway, and the lower part of the opening is closed with an end plate. As the fishway body moves up and down, the lower end of the spiral waterway enters the recess, but the water surface of the spiral waterway meets the water surface of the annular water tank. Here, the spiral shape may be circular or rectangular in cross section in the direction of the spiral axis, and may have a horizontal waterway in the waterway.

In order to raise the fishway main body to a set height, an expansion / contraction chamber is provided below the pedestal. The expansion / contraction chamber has a pedestal as an upper surface, and a watertight rubber is arranged on the outer periphery of the pedestal so as to be in close contact with the recess side wall. Alternatively, the upper end of the bellows type tubular body may be fixed to the pedestal and the lower end may be fixed to the floor surface of the concave portion to form the expansion / contraction chamber. Further, by controlling the operation of the expansion / contraction chamber, a proper amount of water is sent to the expansion / contraction chamber so that the fishway main body floats to the height of the upstream side water level and the upper end of the spiral water channel is in contact. Therefore, adjacent to the upper end of the spiral water channel is provided with an inflow pipe that connects the inflow water tank communicating with the flowing water and the expansion chamber, and the expansion chamber is provided with an outflow pipe communicating with the downstream water channel,
Moreover, the diameter of the inflow pipe swallow portion is made larger than the opening diameter of the outflow pipe. As a result, when water enters the expansion chamber,
The body of the fishway rises, and at some point, the body of the fishway descends if the amount of overflow at the mouth of the inflow pipe decreases and the amount of outflow increases. Therefore, this balance is maintained to stabilize the communication with the upstream waterway.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings. First, as shown in FIGS. 16 and 17, the dam body (weir body) 16 penetrates the discharge water channel 17 in the embankment and the fishway is provided from the outlet of the discharge water channel 17 in the embankment to the downstream water channel. In the case where the fishway has a large height difference in the dam, it is also an example to combine the fishway device 18, the fixed fishway 19 and the stackable fishway device 20 according to the present invention. The discharge water channel 17 in the bank is designed to be able to flow down even at the upper limit water level or the lower limit water level, and a water control gate 21 is provided on the reservoir side and a backup gate 22 is provided on the exit side. As shown in FIGS. 1 and 2, the fishway device 18 according to the present invention is a riverbed 2 immediately downstream of the dam body 16.
A fishway main body 27 composed of a spiral water channel 25 and a pedestal 26 is floated in a circular recess 24 formed in 3. Reference numeral 28 in FIG. 16 is a sub-dam. Further, a screen 30 is provided at the inflow / outflow port of the spillway 29 provided at the connecting portion between the fishway device 18 and the fixed fishway 19 according to the present invention.
Is stretched.

As shown in FIGS. 1 to 3, a main column (vertical axis) 31 is erected at the center position on the bottom surface of the recess 24, and a stopper 32 is fixed at the upper end and extends laterally from the stopper 32. The plurality of columns 33 are supported by the upstream arc-shaped side wall 34. The pedestal 26 is formed in a disk shape, and a steel material is stretched on the lower portion thereof to have high strength so as to withstand water pressure. Also,
The lower boss 35 provided at the center of the pedestal is inserted into the main column 31 via a watertight rubber (O-ring etc.) 36 so as to maintain the watertightness (see FIG. 6), and as shown in FIG. Is fitted with a watertight rubber 37 and closely adhered to the side wall 38 of the recess, and an expansion / contraction chamber 39 is formed in the lower portion of the pedestal. Further, the pedestals 40 that support the pedestal 26 when it is at the lower limit position are arranged at four locations on the bottom surface of the recess.

Further, as shown in FIGS. 1 and 6, an upper boss 42 and a lower boss 3 are provided at the upper and lower ends of a cylindrical body 41 which is inserted into the main column 31.
5 is welded, and as shown in FIG. 1 and FIG.
A cylindrical portion 43 formed of a lined steel plate at the center of 6 is fixed to the upper boss 42, the lower boss 35, and the tubular body 41 via a steel material. The outer side wall 44 and the bottom portion 45 are spirally formed on the outer circumference of the cylindrical portion 43 by using a steel plate to provide the spiral water channel 25 for fishway. The slope of the spiral waterway 25 shall be suitable for fish swimming, and the partition walls 46 should be arranged at regular intervals.
Similar to the slope, the partition shape is suitable for fish going up and down. The partition wall 46 is an ice harbor type (Fig. 1
3) is used.

It is sufficient that the outer side wall 44 does not have to be assembled along the spiral shape but merely serves as a side wall for the water channel 25. Further, one outer side wall 44 that circulates may be continuous with the outer side walls 44 of the water channels above and below it, but it is preferable that a sufficiently large window through which fish can pass is continuously opened. Further, in the bottom part 45, the bottom part between the walls may be a horizontal plane and may be stepwise. Further, as shown in FIG. 12, an annular water tank 48 is formed around the recess at the outer circumferential position of the water channel by the arcuate side wall 47 communicating with the upstream side wall 34. A metal net 49 is provided at a river bed height position of the annular water tank to prevent entry into the recessed portion, so that the upstream fish is not caught when the fishway main body 27 is raised or lowered. Note that a steel plate roof 50 is provided on the upper surface of the cylindrical portion shown in FIG. 2 in order to prevent rainwater from entering, and a round lid 51 is provided in the maintenance passage hole.

Next, the upstream end of the spiral water channel 25 will be described. The upstream end of the spiral water channel 25 is the discharge channel 1 in the bank.
7, the opening of the discharge water channel 52 extends from the upper limit water level to the lower limit water level, and a watertight rubber 53 is arranged around the opening as shown in FIG. In addition, as shown in FIG. 10, the fishway main body 27 that moves up and down is provided with an end plate 54 for blocking the opening of the discharge water channel 52 (see FIG. 7). The opening and the end plate 54 may not be curved depending on the joining conditions.
Further, a concave portion that coincides with the upstream end opening of the spiral water channel 25 is formed in the upper part of the end plate 54 so as to communicate with the discharge water channel 52. Further, the surface of the end plate 54 is separated from the outer peripheral surface of the spiral water channel 25, and a space is provided in which the fish can sufficiently swim and pass. In addition, FIG. 12 and FIG.
As shown in FIG. 3, side rollers 55 are attached to the left and right at locations above the end plate 54 that do not interfere with the water flow, and the side rollers 55 are brought into contact with the door stop 56 buried on both sides of the inner wall of the discharge water channel 52, and the fishway main body. 27 spiral waterways 25
The rotation due to the flowing water is suppressed.

The downstream end of the spiral water channel 25 has a bottom portion 45.
Are smoothly and continuously connected to the surface of the pedestal 26, and the flowing water flows into the annular water tank 48 on the outer periphery of the spiral water passage 25, flows over the partition wall 46, and flows downstream. The spillway 29 described above keeps the water surface of the annular water tank 48 constant.

Next, FIG. 2 and FIG. 8 around the expansion / contraction chamber 39.
This will be described with reference to FIG. In order to make the height position of the fishway main body 27 follow the upstream water level of the discharge water channel 52, first,
An inflow water tank 57 is provided adjacent to the uppermost water channel entrance, a communication hole 58a is formed in a lower portion of a side wall 58 separating the water channel 25 and the inflow water tank 57, and a screen 59 is attached. An inflow pipe 60 having an end projecting from the water tank floor is connected to the expansion / contraction chamber 39 in the inflow water tank 57, and the most upstream partition wall 46 is flush with the inflow pipe 60, and the swallowing port of the inflow pipe 60 is It is several cm lower than the upper end of the most upstream partition. Further, the air supply pipe 61 is inserted so that the inflow pipe 60 is not blocked by the overflow from the swallowing port and air cannot be removed.
The upper portion of the air supply pipe 61 is fixed by a side wall near the air supply pipe 61 and is in a suspended state.

At the lower part of the expansion / contraction chamber 39, as shown in FIGS. 1 and 2, an outflow pipe 62 and a discharge pipe 63 are attached,
The discharge pipe 63 is always closed. The outflow pipe 62 maintains the natural flow and extends to the downstream side. As shown in FIG.
4, the main valve 65 (flow rate adjustment valve) is installed, the fixed fishway 19
To the de-energizing chamber 66 communicating with the. The outflow pipe 6
The diameter of the second pipe outlet is set to be sufficiently smaller than the diameter of the inlet port of the inflow pipe 60.

Next, the operation of the fishway device 18 according to the present invention will be described. When the upstream water is not flowing down to the fishway device 18 and the outflow pipe 62 is open, the expansion / contraction chamber 3
Most of the water 9 flows out, and the fishway body 27 is supported by the pedestal 40. When the sub-valve 64 of the outflow pipe 62 is closed and the water level of the reservoir dammed up by the dam 16 rises and water flows into the inflow water tank 57 through the discharge water channel 52, initially, the drinking water of the inflow pipe 60 is swallowed. Before the water level rises to the mouth and the overflow water depth on the notch weir of the uppermost partition wall 46 installed in the waterway 25 does not become excessive, overflow is started from the swallowing mouth (see FIG. 9). Water is stored in the expansion / contraction chamber 39 through a space between the outer circumference of the air supply pipe 61 and the inner circumference of the inflow pipe 60. In addition, the air supply pipe 61
The upper end of is attached above the upper end of the inflow pipe 60,
Since there is sufficient air supply inside the inflow pipe 60,
An adhering flow can be created between the air supply pipe 61 and the air supply pipe 61, and a certain amount of overflow from the upstream water level can be reliably introduced into the expansion / contraction chamber 39. Therefore, the air inside the expansion chamber 39 can be smoothly extracted from the air supply pipe 61, and a free water surface can be obtained inside the air supply pipe 61.

The expansion / contraction chamber 39 exceeds the full state, and the inflow pipe 60
When the internal free water surface rises and a pressure head is generated, the height acts on the lower surface of the pedestal 26 to raise the fishway body 27. The fishway main body 27 is guided by the main pillar 31 and rises in the vertical direction. Then, when the drinking port of the inflow pipe 60 of the fishway main body 27 rises to near the upstream water level, the sub valve 64 is opened,
The expansion / contraction chamber 39 is drained through the outflow pipe 62. At this time, since the diameter of the swallowing portion of the inflow pipe 60 is made sufficiently larger than the diameter of the outlet of the outflow pipe 63, the free water level further rises and the pressure exerted on the lower surface of the pedestal 26 increases, and the fishway main body 27. Continues to rise. The auxiliary valve 64 is closed in the initial stage of its movement because it takes a long time to keep the expansion chamber 39 filled with water.

When the fishway main body 27 further rises, the overflow water depth at the swallowing port of the inflow pipe 60 gradually decreases, and if the overflow amount and the outflow amount from the outflow pipe 62 become equal, the vertical position of the fishway main body 27 is maintained. . Further, if the upstream water level rises and the overflow depth slightly increases, the free water level rises and the fishway body 27 also rises, so the position of the inflow pipe 60 swallowing port becomes higher and the overflowing water depth at the swallowing port becomes smaller. As a result, the once increased inflow amount in the inflow pipe 60 is reduced, the free water surface in the inflow pipe 60 is restored, and the pressure acting on the lower surface of the pedestal 26 is also changed to the original pressure, so that the fishway main body 27 stops. The overflow water depth of the notch weir of the partition wall 46 is appropriately maintained.

In the fishway device 27 of the present invention, since the cross-sectional area of the inflow pipe 60 is sufficiently smaller than the plane area of the expansion / contraction chamber 39, the inflow pipe 60 can be freely moved even if the fishway main body 27 is raised slightly. The water surface water level greatly decreases, the pressure acting on the lower surface of the pedestal is drastically reduced, and the fishway main body 27 does not move greatly at one time. However, if the water level of the reservoir continues to rise, the amount of inflow from the swallowing port of the inflow pipe 60 will increase every moment, so that the fishway body 27 will continuously rise in small increments.

On the other hand, when the water level of the reservoir drops and the overflow water depth at the swallow of the inflow pipe 60 slightly decreases, the inflow amount into the inflow pipe 60 decreases, but the amount of water discharged from the outflow pipe 62 is replenished. Since it does not break, the free water level in the inflow pipe decreases, the water pressure acting on the lower surface of the pedestal decreases, and the fishway main body 27 descends. In this case as well, it goes without saying that the movement per stroke is extremely small, but the outflow pipe 6
Since the size of 2 is determined in consideration of the rate of decrease of the reservoir water level, the flow rate of the spiral water channel 25 of the fishway main body 27 does not drastically decrease because it cannot keep up with the decrease of the reservoir water level.

As described above, the fishway body 27 follows the upstream water level and floats in the recess 24 at the set height.
As shown in FIG. 8, the stored water overflows the partition wall 46, passes through the spiral water passage 25, and joins the annular water tank 48. Then, it overflows the partition of the fixed fishway 19 and flows downstream.

In the fishway main body 27, the water in the spiral water channel 25 joins the annular water tank 48, but due to the floating height of the fishway main body 27, the spiral water channel 25 sinks into the annular water tank 48, as shown in FIG. The merging surface a where the water surface of the spiral water channel 25 and the water surface of the annular water tank 48 contact each other may come to the upstream side. The outer side wall 44 of the water channel 25 projects from the confluence surface a, but is hidden in the water, and the run-up fish enters the annular water tank 48 from the fixed fishway 19 and enters the water channel 25 from the position of the interrupted outer side wall 44. Further, as shown in FIG. 20, the height position of the fishway main body 27 changes depending on the height of the upstream water level, and the confluence surface a with the annular water tank 48 differs from that shown in FIG. Therefore, the run-up fish swim in a slope suitable for run-up even if the upstream water level changes.

Next, modified examples of individual members of the fishway device 18 will be described. The outflow pipe 62 provided in the expansion / contraction chamber 39 may be directly connected to a downstream water channel below the fixed fishway 19 as long as a natural flow is used. Further, as shown in FIG. 2, the outflow pipe 62 drawn from the lower portion of the expansion / contraction chamber 39 is bent to be exposed on the ground surface, and the vertical line pump 67 is placed there.
And a flow rate adjusting valve 68 is provided at the pump outlet, and a discharge pipe 69 connected to the flow rate adjusting valve 68 is connected to a depressurizing chamber 66 communicating with the fixed fishway 19 to mechanically pump and discharge water. Also good. Further, at the beginning of filling the expansion / contraction chamber 39 with water, it may be possible to directly supply the water to the recess 24 without using the fishway main body 27, but with a supply pipe (not shown) equipped with an opening / closing valve.

Further, as shown in FIG. 14, a belt ring-shaped double-foldable curtain seal 70 is attached between the peripheral edge of the pedestal 26 and the intermediate portion of the recess 24 to form a closed expansion / contraction chamber 39. Since this structure has less friction than the watertight rubber 37 interposed between the pedestal 26 and the recess 24, durability and operability are expected. Also, as shown in FIG.
A ring-shaped storage portion 24a is formed in the bottom surface of the recess 24, a cylindrical bellows flexible film 71 is installed, the upper end is fixed to the lower portion of the pedestal 26, and the lower end is brought into close contact with the bottom surface of the storage portion 24a. This facilitates the smooth movement of the fishway body 27.

Next, the spiral water channel 25 of the fishway main body 27.
FIG. 21 shows the configuration of the rectangular cross section of FIG.
25 to FIG. 25. The description of the same members as those in the case where the circular spiral water channel is used is omitted. Recess 2 for accommodating the fishway body 27
4 has a rectangular horizontal cross section, and the pedestal 26 has a rectangular shape that matches the recess 24. Also, the pedestal 2
A rectangular tube 72 is formed of a lined steel plate at the center of 6, and the water channel 25 is provided spirally on the outer side thereof, and the bottom surface at the lower end of the water channel is arranged so as to contact the bottom surface of the pedestal 26. The upper end opening of the water channel 25 is connected to the discharge water channel 52. Further, in the water channel 25, partition walls 46 in which the central part of the Norwegian system is a notch weir are sequentially installed at intervals. On the other hand, triangular truss frames 73 are erected in the middle portions of the opposite sides of the linear side wall 34 facing the recess 24, and the columns 33 extend from both upper ends to support the upper ends of the main columns 31.

The pedestal 26 is provided with a rectangular spiral water channel 25 centered on the rectangular tube 72, and the straight horizontal water channel 25a and the inclined water channel 25 are arranged so that the horizontal flow and the inclined flow alternate.
b and b are alternately connected along the side. That is, the outlet end of the inclined waterway 25b is in contact with the next horizontal waterway 25a, the outlet end of the horizontal waterway 25a is connected to the next inclined waterway 25b, is further connected to the horizontal waterway 25a, and is alternately connected in the right-angled direction. The bottom of 25 is attached to the bottom of the pedestal 26. Since the water channel 25 is combined with the rectangular tube 72 as the center to increase the rigidity, the horizontal water channel 25
Although the combination of a and the inclined water channel 25b may be another combination, they are alternately connected in consideration of smoothly following the water level fluctuation. Further, since the upper end of the water channel 25 forms a horizontal water channel 25a, it facilitates communication with the discharge water channel 52 on the upstream side, and the end plate 54 attached to the communication point is flat. Further, the side rollers 55 are attached to both side walls on the side of the inclined water passage 25b, and
8 is provided with a door stop 56. The water channel 25 configured in this way can be made of the same material as the stacked fishway device 20, and the manufacturing cost can be suppressed. Further, since the spiral channel 25 secures the channel space, there is no problem even if the horizontal channel 25a is provided as a resting place for the upstream fish.

[0033]

EFFECTS OF THE INVENTION Since the present invention is constructed as described above, the fishway body is made to float and sink by utilizing the natural force of running water without using mechanical force, and automatically follow the water level of the reservoir. Therefore, the overflow water depth on the channel partition can be kept constant at any water level in the reservoir, and the amount of water flowing down can be maintained to keep the run-up conditions constant. In addition, the configuration to control the vertical movement of the fishway body is that only the space below the fishway body is closed to form an expansion and contraction chamber, and an overflow swallowing port and an outlet are provided to communicate with the expansion and contraction chamber. Because there are, management costs and construction costs can be reduced. Furthermore, since the fishway body moves up and down in the vertical direction, the body structure is extended to the allowable range of body strength, main column strength, and buoyancy.
If it is expanded, it will be possible to absorb part of the difference in vertical water level in addition to the fluctuation water level width. Therefore, the horizontal distance of the concrete water level corresponding to the absorbed amount can be shortened and the civil engineering cost can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a fishway device according to an embodiment of the present invention.

FIG. 2 is a top view of the fishway device shown in FIG.

FIG. 3 is a side sectional view of the fishway device shown in FIG.

FIG. 4 is a side view showing a watertight structure of the expansion / contraction chamber in the lower portion of the fishway body shown in FIG.

5 is a top view for explaining the outflow mechanism of the expansion / contraction chamber shown in FIG. 1. FIG.

FIG. 6 is a side view of the periphery of a boss that supports vertical movement of the fishway body shown in FIG.

FIG. 7 is a top view showing the connection between the upper end of the water channel of the fishway main body shown in FIG. 1 and the upstream water channel.

8 is a top view of the swallow provided at the upper end of the waterway of the fishway body shown in FIG. 1. FIG.

9 is a cross-sectional view of the swallow shown in FIG.

10 is a front view of an end plate provided at the upper end of the water channel of the fishway main body shown in FIG.

11 is a front view of an opening of an upstream water channel which is in close contact with the end plate shown in FIG.

FIG. 12 is a top view of the fishway device shown in FIG.

13 is a cross-sectional view of the fishway device shown in FIG.

14 is a cross-sectional view showing a watertight structure of the expansion / contraction chamber of the fishway device shown in FIG.

15 is a cross-sectional view showing a watertight structure of the expansion / contraction chamber of the fishway device shown in FIG.

16 is a cross-sectional view showing a state in which the fishway device shown in FIG. 1 is deployed in a dam facility.

FIG. 17 is a top view of the fishway of the dam facility shown in FIG.

FIG. 18 is a schematic view for explaining the action of the fishway device of the present invention.

FIG. 19 is a plan view showing the confluence of the spiral water channel of the fishway body and the annular water tank.

FIG. 20 is a plan view showing another confluence point between the spiral water channel of the fishway body and the annular water tank.

FIG. 21 is a top view of a fishway device according to another embodiment.

22 is a sectional view of the fishway device shown in FIG. 21. FIG.

23 is a partial cross-sectional view of the spiral water channel shown in FIG.

24 is a top view when the position of the fishway main body of the fishway device shown in FIG. 21 is changed.

FIG. 25 is a cross-sectional view when the fishway body shown in FIG. 21 is in a lower position.

FIG. 26 is a perspective view of a conventional fixed concrete spiral fish path.

27 is a top view of the fishway shown in FIG. 26. FIG.

FIG. 28 is a cross-sectional view of a conventional upstream water level tracking type fishway device.

[Explanation of symbols]

 16 weir 23 river bed 24 recess 25 spiral channel 25a horizontal channel 25b inclined channel 26 pedestal 27 fishway main body 31 vertical axis 34 side wall 37 watertight rubber 38 concave side wall 39 expansion chamber 46 partition wall 47 side wall 48 annular water tank 52 discharge water channel 54 mirror plate 57 Inflow water tank 60 Inflow pipe 62 Outflow pipe 71 Cylindrical body

Claims (7)

[Claims] 1. A recess is formed in the riverbed immediately downstream of a weir body that crosses a river, and a vertical axis having a height higher than the upper limit water level of the running water discharged from the weir body is provided upright on the bottom surface of the recess. , A pedestal conforming to the horizontal cross-sectional shape of the recess is vertically movably supported by the vertical axis, and has a slope extending vertically from the pedestal and suitable for fish run-up and descent. A fishway main body is formed by a spiral water channel, an expansion / contraction chamber having the pedestal as an upper surface is formed in the lower part of the pedestal, and a pipe line for inflowing / storing the flowing water of the upstream side of the weir body into the expansion / contraction chamber and the downstream side. An outflow pipe for outflowing to the side water channel is provided, and the upper end of the spiral water channel is exposed to the discharge water channel communicating with the upper and lower water levels of the stored water, and the upper end of the spiral water channel is opened to open the discharge water channel. And an end plate that closes the lower part of the opening of the discharge channel to the fishway body. A side wall is formed on the riverbed at an outer circumference of the spiral waterway or an outer circumference of the pedestal with a space where fish can swim, and an annular water tank surrounded by the side wall is connected to the downstream waterway via a partition wall. Floating type fishway device characterized by that. 2. The floating fishway device according to claim 1, wherein a vertical axis is provided at the center of the pedestal. 3. The floating fishway device according to claim 1, wherein the expansion / contraction chamber is formed by arranging a watertight rubber on the outer periphery of the pedestal and closely contacting the side wall of the recess. 4. The floating fishway device according to claim 1, wherein an upper end of an expandable cylinder is fixed to the lower surface of the pedestal, and the lower end is fixed to the floor surface of the recess to form an expansion / contraction chamber. . 5. The conduit for inflowing / storing the flowing water on the upstream side of the weir body is composed of an inflowing pipe which is adjacent to the upper end of the spiral water channel and which connects the inflowing water tank communicating with the flowing water and the expansion / contraction chamber. ,
2. The floating fishway device according to claim 1, wherein the diameter of the inlet pipe swallow portion is larger than the diameter of the outlet pipe. 6. The floating fishway device according to claim 1, wherein the spiral water channel has a circular cross-section in the axial direction of the spiral to have a constant slope. 7. The spiral water channel has a rectangular cross section in the direction of the spiral axis, and is horizontally, slanted, horizontally or slanted alternately for each side so as to circulate. Item 2. A floating fishway device according to item 1.