JP3839892B2 - Paddy field level control device and water management system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a water level control device and a water management system for paddy fields. More specifically, the present invention relates to a water level control device that can easily adjust the surface water level of each cultivation area in a paddy field to a desired height. This is a paddy field water management system that can automatically manage supply and discharge, and more specifically, by supplying the minimum necessary amount of water to each cultivation area, it is possible to supply water uniformly throughout the paddy field, and each cultivation area It is related with the water management system of the paddy field which can maintain the water level of this.
[0002]
[Prior art]
FIG. 9 is a schematic plan view showing a conventional paddy field structure. Water flowing through the river 1 is led from the water channel 2 to the upstream main water supply channel 3 and supplied to the paddy field 4. The paddy field 4 is divided into a plurality of cultivated areas 42 by the shore 41, and an open-type water supply channel 31 is provided along each of the cultivated areas 42 at the side edge of the farm road 40 extending in the longitudinal direction. . An upstream side of the water supply channel 31 is connected to the main water supply channel 3, and a water supply port 32 is provided on a side wall of the water supply channel 31 facing each cultivation area 42. As shown in a perspective view in FIG. 10, the water flowing through the water supply channel 31 is supplied from the water supply ports 32 to the cultivated areas 42.
[0003]
An open drainage channel 33 is provided between the paddy fields 4 and 4 located on the opposite side of the water supply channel 31. A water level setter 34 is provided at the drainage outlet of the drainage channel 33 facing each cultivated area 42. By adjusting the height of the water level setter 34, the surface water level of each cultivated area 42 is kept constant. It is formed so that it can be maintained at a height. The downstream side of the drainage channel 33 is connected to the main drainage channel 35, and excess irrigation water and rainwater discharged to the drainage channel 35 are returned to the river from the water channel 36.
[0004]
[Problems to be solved by the invention]
In the case of this paddy field, the irrigation water flowing through the water supply channel 31 flows into each cultivated area 42 from the water supply port 32 located on the upstream side of the water supply channel 31. Then, the water supplied to the cultivation area 42 is maintained at a constant water level by the water level setting device 34, and surplus water is discharged to the drainage channel 33. In this way, since the water is sequentially supplied from the upstream side toward the downstream cultivation area 42, the supply of the water tends to be insufficient in the downstream cultivation area 42. In particular, during the drought period where sunshine continues, water is hardly supplied to the downstream cultivated area 42, resulting in a decrease in yield due to poor growth of rice.
[0005]
In addition, the conventional paddy field in which each water channel is formed in an open type has a problem that the farmland cannot be effectively used because the space of the cultivation area 42 and the farm road 40 is narrowed by the occupied width of the water supply channel 31 and the drainage channel 33. It was. Furthermore, since sediments and the like are likely to fall and accumulate in each water channel that opens upward, there has been a problem that drainage work of soil and the like must be frequently performed, and water channel management is troublesome.
[0006]
On the other hand, with the urbanization of rural areas, farmers are becoming part-time workers, and there is a growing demand for automation and labor saving of farming work due to shortening and restriction of working hours, and labor saving such as water supply management and fertilization management of paddy fields. Is desired.
[0007]
Therefore, the present invention is capable of supplying water in a stable state over the entire paddy field, can maintain the surface water level automatically at a constant level, is excellent in workability, and can be provided at a low cost, and a water level control apparatus and water management for paddy fields. The purpose is to provide a system.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the water level control apparatus for paddy fields according to the present invention is provided along the farm road in the vicinity of the bottom of a bottomed cylindrical water supply / drainage basin having a cultivation area water supply / drainage port communicating with the cultivation area of the paddy field. A water supply / drainage section connected to the water pipe via a water supply / drainage valve is provided, and the water supply / drainage section is provided with a drainage valve that can be opened near the bottom of the water supply / drainage tank. It features a water level control weir.
[0009]
Furthermore, water level control device of the present invention, the cultivation Ward plumbing port, that you are communicating with the farming ku through the height-adjustable overflow gate, the previous SL level adjustment weir, the water supply and drain section It is characterized in that it is formed by a cylindrical body that is fitted to the upper end portion of the pipe that is open to the top and that is open upward.
[0010]
The water management system for paddy fields according to the present invention is a paddy field water management system in which a farm road is provided on a side edge and is divided into a plurality of cultivated areas by a shore, and includes a water supply pipe and a drain pipe along the farm road. Are embedded in each cultivated area, and at least two water level adjusting devices connected to the water supply pipe and the drain pipe, respectively, are installed in the bottomed cylindrical water supply / drainage basin. A water supply / drainage port connected to the water supply pipe or the drainage pipe, and the water supply / drainage unit includes a water level adjustment weir that is adjustable in height and opens at an upper part of the water supply / drainage basin; A drainage valve that can be opened near the bottom of the water supply / drainage basin, connected to the water supply pipe via a water supply / drainage valve, and by opening the water supply / drainage valve of the water level adjusting device installed on the water supply pipe side. Excess water supplied from the water supply pipe through the water supply / drainage section, through the water level control weir set at a predetermined height and flowing into the water supply / drainage basin to the farming area through the water supply / drainage port. Or rainwater flows into the water supply / drainage through the water supply / drainage port of the water level control device installed on the drainage pipe side, passes through the water level control weir adjusted to the surface water level, and is discharged from the water supply / drainage section to the drainage pipe. By opening the valve, the construction is such that the water in the water supply / drainage basin and the earth and sand flowing into the water supply / drainage basin are discharged.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a schematic plan view showing an example of a water management system using the water level adjusting apparatus of the present invention. The interior of the paddy field 4 is divided into a plurality of cultivated zones 42 by a ridge 41 extending in the short direction. Each cultivated area 42 is divided into, for example, a rectangular shape having a long side of about 100 to 200 m and a short side of about 30 to 100 m. Yes.
[0012]
A farm road 43 is provided along the longitudinal direction of the side edge of the paddy field 4. The upper surface of the farm road 43 has a central portion formed on a flat surface having substantially the same width as the conventional farm road, and an inclined surface having a downward slope toward one side or both sides of the flat surface toward the paddy field 4 side. Is formed. This inclined surface is a portion where the irrigation channels and drainage channels that have conventionally been provided along the agricultural roads are removed and backfilled. For this reason, the agricultural road 43 is considerably wider than the conventional agricultural road, and the direction can be changed by turning a tractor or the like, or one of the agricultural roads 43 can be used as a parking space.
[0013]
In each agricultural road 43, a water supply pipe 51 and a drain pipe 52, which are water passage pipes for passing water, are buried below the inclined surface. The water supply pipe 51 and the drain pipe 52 are connected to the water line 37 on the upstream side via valves 51a and 52a, and are connected to the drain line 38 on the downstream side via valves 51b and 52b. The water line 37 and the drain line 38 may be formed of an open water channel or a pipeline depending on the situation. Although not shown, the water line 37 is connected to a water channel for drawing water from the river, and the drain line 38 is connected to a water channel for returning the discharged water and rainwater to the river. is doing.
[0014]
In addition, two water level adjusting devices 6 communicating with each cultivation area 42 via the cultivation area water supply / drainage port 61 are installed at the side edge of each cultivation area 42, each serving as one water supply side. The water level adjusting device 6 is connected to the water supply pipe 51 through a water supply / drainage valve 62, and the water level adjustment device 6 on the other water drainage side is connected to the drainage pipe 52.
[0015]
FIG. 2 is a schematic piping diagram showing an example of the water level adjusting device 6 used for irrigation management of the one cultivation area 42. The water level adjusting device 6 is a water level adjusting device of the type having the built-in water supply / drainage valve 62. A bottomed cylindrical water supply / drainage trough 60 is provided with a water supply / drainage port 61, which is in communication with the cultivation area 42, and a water supply pipe. 51 (or drainage pipe 52) is provided with a water supply / drainage unit 63, and the water supply / drainage unit 63 includes the water supply / drainage valve 62, a drainage valve 64 that can be opened near the bottom of the water supply / drainage basin 60, and a water supply / drainage. A height-adjustable water level adjusting weir 65 opening at the top of the ridge 60 is provided.
[0016]
3 and 4 show examples of specific shapes of the water level adjusting device 6, FIG. 3 is a longitudinal sectional view, and FIG. 4 is a plan view. FIG. 5 is a perspective view of a slide valve used as the water supply / drain valve 62 and the drain valve 64.
[0017]
This water level adjusting device 6 is provided with various water supply / drainage means in a water supply / drainage basin 60. As described above, the water supply / drainage means is provided in the water supply / drainage port 61 connected to the farming zone 42, the water supply / drainage portion 63 connected to the water supply pipe 51 (or the drainage pipe 52), and the water supply / drainage portion 63. The water supply / drainage valve 62, the drainage valve 64 that can be opened near the bottom of the water supply / drainage basin 60, and the height-adjustable water level adjustment weir 65 that opens at the top of the water supply / drainage basin 60 are provided. Further, the cultivation area water supply / drain opening 61 is provided with an overflow gate 66 that is height-adjustable and detachable.
[0018]
The water level adjusting weir 65 is slidable and slidable in an upward opening at the upper end of the pipe 65P rising vertically from the horizontal pipe 63P between the water supply / drainage valve 62 and the drainage valve 64 of the water supply / drainage section 63. It is formed by a cylindrical body 65T fitted so as to be movable up and down via a rubber seal packing for obtaining resistance. The cylinder 65T is provided with an operation rod 65H for moving the cylinder 65T up and down so as to extend above the water supply / drainage rod 60. In addition, by discharging the upper edge of the cylinder 65T into a trumpet shape, the water can be discharged efficiently.
[0019]
As shown in FIG. 5, the slide valve 70 used as the water supply / drainage valve 62 and the drainage valve 64 includes two plate-like members 72, 73 each having a through-hole 71 corresponding to the pipe 63 </ b> P of the water supply / drainage unit 63. A plate-shaped valve body 74 is provided between the valve body 74 so as to be movable up and down, and a valve rod 75 for opening and closing operation is attached to the valve body 74. Operation rods 62H and 64H similar to the operation rod 65H are provided on the valve rods 75 of the water supply / drainage valve 62 and the drainage valve 64, respectively.
[0020]
Each of the operating rods 62H, 64H, 65H can be provided with a scale for displaying the open / closed state of the valve and the like. In addition, a lid can be attached to the upper portion of the water supply / drainage basin 60.
[0021]
The overflow gate 66 provided at the cultivation area water supply / drainage port 61 is formed by two upper and lower weir plates 81 and 82 provided at the cultivation area side opening of the outlet rod 80 opened at the cultivation area 42 side. The barrier plates 81 and 82 are inserted into two concave grooves 83 provided on both sides so that the vertical position can be adjusted and detachable, and the vertical positions of the barrier plates 81 and 82 are adjusted and removed. Thus, the inflow of earth and sand into the water supply / drainage basin 60 is prevented, or the drainage of the cultivation area 42 is performed quickly.
[0022]
The water level adjusting device 6 having the above-described configuration is buried in a vertical state on the inclined surface of the farm road 43 facing each cultivated area 42, and the paddy water level is set for each cultivated area 42. Although one section of the paddy field 4 is flattened so that each cultivation section 42 has the same height, there may be a slight difference in height in each cultivation section 42 depending on the condition of the topography. Therefore, the height position of the water level adjusting weir 65 in the water level adjusting device 6 installed in each cultivation section 42 is set for each cultivation section 42 by moving the operation rod 65H provided on the cylindrical body 65T up and down.
[0023]
Usually, in the water level adjusting device 6 installed in each cultivated area 42, the water level adjusting weir 65 of the water level adjusting device 6 installed on the water supply pipe 51 side is a position where the upper edge of the cylinder 65T is slightly higher than the surface water level L. The water level adjusting device 6 installed on the drainage pipe 52 side sets the upper edge of the cylinder 65T to a height corresponding to the surface water level L. Further, the water supply / drainage valve 62 of the water level adjustment device 6 on the water supply pipe 51 side is appropriately opened, the water supply / drainage valve 62 of the water level adjustment device 6 installed on the drainage pipe 52 side is fully opened, and the drainage valves 64 are both fully open. Closed. Furthermore, the height of the overflow gate 66 is set at a position lower than the surface water level L and higher than the ground surface.
[0024]
In the above setting state, first, in the water level adjusting device 6 installed on the side of the water supply pipe 51, the water from the water supply pipe 51 passes through the pipe 63P from the water supply / drainage section 63 via the water supply / drainage valve 62 opened by a predetermined amount. After rising in the pipe 65P and flowing into the water supply / drainage basin 60 over the upper edge of the cylinder 65T of the water level control weir 65, the water is supplied from the cultivated area water supply / drainage port 61 to the cultivation area 42 through the overflow gate 66. . At this time, since the upper edge of the cylindrical body 65T is set at a position slightly higher than the water level L on the surface, even if the supply of the water to the water supply pipe 51 is stopped, the water does not flow backward to the water supply pipe 51 side. Moreover, since the overflow gate 66 is set at a position higher than the ground surface, the earth and sand in the cultivation area 42 does not flow into the water supply / drainage basin 60.
[0025]
On the other hand, in the water level adjusting device 6 installed on the drainage pipe 52 side, the upper edge of the cylinder 65T of the water level adjusting weir 65 is adjusted to a height corresponding to the surface water level L, so the surplus supplied to the cultivation area 42 Water and rainwater flow into the water supply / drainage basin 61 from the cultivation area water supply / drainage port 61 through the overflow gate 66 and then flow down through the pipe 65P over the upper edge of the cylinder 65T. It is discharged to the drain pipe 52.
[0026]
Therefore, the field level in each cultivation area 42 can be automatically adjusted by adjusting the cylinder 65T of the water level adjusting weir 65 of the water level adjusting device 6 installed on the drain pipe 52 side to a predetermined height. . And by appropriately adjusting the opening of the water supply / drainage valve 62 of the water level adjusting device 6 installed on the water supply pipe 51 side, the amount of water for inflow into the cultivation area 42 can be adjusted, and the water level at the surface can be adjusted with the minimum required amount of water. It can be kept constant.
[0027]
By performing such irrigation management, the amount of irrigation water supplied to each cultivated area 42 can be reduced, so that irrigation water can be supplied uniformly from the upstream cultivated area 42 to the downstream cultivated area 42, There will be no shortage of water in the cultivated area 42. Moreover, since the inflow of water to the cultivation area 42 can be reduced, the agricultural chemicals and fertilizer applied to the cultivation area 42 are less likely to flow out to the outside, and there is no risk of causing environmental damage.
[0028]
When water is discharged from the cultivation area 42, the water supply / drainage valve 62 of the water level adjustment device 6 installed on the water supply pipe 51 side is closed, and the water level adjustment weir 65 of the water level adjustment device 6 installed on the drainage pipe 52 side is closed. The cylindrical body 65T is pushed down or the drain valve 64 is opened. Thereby, the water stored in the cultivation area 42 can be discharged to the drain pipe 52 from the water level adjusting device 6 installed on the drain pipe 52 side.
[0029]
Furthermore, the earth and sand that has entered the water supply / drainage basin 60 from the cultivating area 42 through the cultivation area water supply / drainage port 61 opens the drainage valve 64 at the bottom of the water supply / drainage basin 60 to the drainage pipe 52 together with the water from the drainage valve 64. Can be discharged.
[0030]
On the other hand, at the time of scratching a paddy field that requires a large amount of water at once, the cylinder 65T of the water level adjusting weir 65 of the water level adjusting device 6 installed on the drain pipe 52 side is pulled up or the water supply / drain valve 62 is closed. Thereby, the water supplied from the water supply pipe 51 flows into the cultivation area 42 from the water level adjusting device 6 installed on the water supply pipe 51 side, and is not discharged from the water level adjusting device 6 installed on the drain pipe 52 side. The whole amount is stored in the cultivated area 42 and quickly reaches a predetermined water level.
[0031]
Further, when water supply to some cultivated areas 42 is not necessary due to reduction or the like, the water supply / drain valve 62 of the water level adjusting device 6 on the water supply pipe 51 side corresponding to the cultivated area 42 is closed, and the water level adjustment on the drain pipe 52 side is performed. The water supply / drain valve 62 of the device 6 is fully opened, and the weir plates 81 and 82 of the overflow gate 66 are removed. As a result, rainwater or the like in the cultivation area 42 is discharged from the cultivation area 42 to the drainage pipe 52 through the water level adjusting device 6 on the drainage pipe 52 side.
[0032]
According to the water level adjusting device 6 configured as described above, since the amount of water flowing through the water supply pipe 51 can be reduced, a small-diameter pipe can be used. Moreover, since a certain flow rate is ensured without giving a big gradient to each pipe 51 and 52, the operation | work which installs the water level adjustment apparatus 6 in each cultivation area 42 can also be performed easily. Moreover, the water level adjusting device 6 can be manufactured by appropriately combining synthetic resin cylinders and the like, and is integrated into the water supply / drainage basin 60, so that the water supply / drainage unit 63 and the cultivation area water supply / drainage port are provided. Since it is only necessary to connect 61 to the water supply pipe 51, the drain pipe 52 and the overflow gate 66 directly or through an appropriate joint, construction costs and the like can be greatly reduced. Moreover, in the conventional flat land irrigation, a pump for pumping water is necessary, but this water level adjusting device 6 can completely eliminate the need, and the water can be fed at an ultra-low pressure.
[0033]
Furthermore, by making the overflow gate 66 into two upper and lower slide type weirs 81, 82, it is possible to prevent earth and sand from entering the water supply / drainage basin 60 when scraping, and also during the middle drying or rotation Water can be drained effectively. That is, if the upper weir plate 81 is pulled up, it is possible to prevent earth and sand from entering the water supply / drainage basin 60 when scraping. Further, when the paddy field is dried, water can be drained by pushing down the upper weir plate 81 and digging up the nearby ground as indicated by reference numeral P1 in FIG. Furthermore, when reducing or rolling, the upper and lower weir plates 81 and 82 are pulled up or removed, and the nearby ground is dug down about 30 cm as indicated by reference numeral P2 in FIG. There is an advantage that can be.
[0034]
Also, when scraping, reducing, or rolling, these operations can be performed efficiently by opening and closing the valves 51a, 51b, 52a, 52b provided at both ends of the water supply pipe 51 and the drain pipe 52. Normally, the valve 51a on the water line 37 side of the water supply pipe 51 is open, the valve 51b on the drain line 38 side is closed, the valve 52a on the water line 37 side of the drain pipe 52 is closed, and the valve 52b on the drain line 38 side. Is set to open. Therefore, the water flowing through the water line 37 flows into the water supply pipe 51 from the valve 51a, is supplied to each cultivated area 42 through the water level adjusting device 6 installed in the water supply pipe 51, and surplus in each cultivated area 42. The irrigation water or the like flows into the drainage pipe 52 through the water level adjusting device 6 installed in the drainage pipe 52 and is discharged from the valve 52b to the drainage line 38.
[0035]
At the time of scraping, the valve 51a, 51b of the water supply pipe 51 is left as it is, the valve 52a on the water line 37 side of the drain pipe 52 is opened, and the valve 52b on the drain line 38 side is closed, thereby It can be used for water supply. That is, the water flowing through the water line 37 flows through the valve 51a to the water supply pipe 51 and flows through the valve 52a to the drainage pipe 52, and the valves 51b and 52b on the drainage line 38 side of both pipes 51 and 52 are closed. Therefore, the entire amount of water is supplied to each cultivated area 42 via each water level adjusting device 6 installed in each of the pipes 51 and 52. Thereby, the cultivation area 42 can be set to the predetermined water level in a short time.
[0036]
On the other hand, the valve 52a, 52b of the drainage pipe 52 is left as it is, and the valve 51a on the water supply line 37 side of the water supply pipe 51 is closed and the valve 51b on the drainage line 38 side is opened. 51 can be used for drainage. That is, the irrigation water flowing through the irrigation line 37 does not flow into the pipes 51 and 52 because the valves 51a and 52a are closed, and the irrigation water and rainwater in the cultivation area 42 are installed in the pipes 51 and 52, respectively. The water flows through the drainage valve 64 of each water level adjusting device 6 and flows out into the water supply pipe 51 and the drainage pipe 52, and is discharged from both the pipes 51 and 52 to the drainage line 38. As a result, the cultivation area 42 can be drained in a short time, and a large amount of rainwater can be discharged smoothly during a heavy rain or long rain.
[0037]
6 to 8 show a reference example of the water level adjusting device . FIG. 6 is a schematic piping diagram, FIG. 7 is a longitudinal sectional view, and FIG. 8 is a plan view. The water level adjusting device 6A shown in this embodiment is obtained by omitting the water supply / drainage valve 62 of the water supply / drainage section 63 in the water level adjustment device 6 shown in the above embodiment, 42 is provided with a water supply / drainage port 61 and a water supply / drainage part 63 connected to the drainage pipe 52 (or the water supply pipe 51). The water supply / drainage part 63 is provided with a drainage valve 64 and a water level adjusting weir 65. It has been. In addition, about another component, the same code | symbol is attached | subjected to the component same as the component in the water level adjustment apparatus 6 of the said example, and detailed description is abbreviate | omitted. Moreover, since the operation in water level adjustment and drainage is the same, description of the action of the water level adjustment device 6A is also omitted.
[0038]
As described above, since the water supply / drainage valve 62 of the water level adjusting device 6 installed on the drainage pipe 52 side is always set to the fully open state in the normal use state, the water supply / drainage valve is omitted on the drainage pipe 52 side. By installing the water level adjusting device 6A, the manufacturing cost of the water level adjusting device can be reduced, and the cost of the entire system can be reduced. Moreover, this water level adjusting device 6A can also be installed in the water supply pipe 51 side by mounting | wearing an appropriate valve with the external piping of the water supply / drainage part 63. FIG.
[0039]
In the above-described embodiment and reference example , the water supply / drainage basin constituting the water level adjusting device is exemplified as a cylindrical shape, but may be rectangular, and the shape of the water supply / drainage basin is not particularly limited. Further, the structure of the water level adjusting weir is not limited to the above-described cylindrical body, but may be formed in a bellows shape or a dam plate type. Further, by forming each operation rod so as to be detachable by, for example, a screwed structure, it is possible to prevent the water level adjusting weir and the like from being operated except when necessary.
[0040]
Moreover, in FIG. 1, although the water level adjustment apparatus was installed in the opposing both sides of each cultivation area extended along the longitudinal direction of a paddy field, it was used for supply and drainage, but supply and drainage were carried out on one side of the cultivation area. It is also possible to install a water level adjusting device, and depending on the area of the cultivation area and the ability of the water level adjusting device, three or more water level adjusting devices can be installed.
[0041]
Furthermore, the opening and closing of each valve and the vertical position adjustment of the overflow weir can be configured so as to be remotely operable by a motor or the like instead of the operation rod, and can be automatically controlled using a computer or the like. .
[0042]
【The invention's effect】
As described above, according to the water level control device and the water management system of the paddy field of the present invention, the water supply pipe and the drain pipe are buried in the farm road provided along the side edge of the paddy field. Space can be greatly expanded, and farmland can be used effectively.
[0043]
In addition, the water level control device can reliably supply water to the farming area, maintain the surface water level, and discharge the water from the farming area with simple operations. Maintain the water level for each farming area. Can be efficiently managed. Furthermore, it is possible to cope with the reduction of some cultivated areas. Moreover, since these functions are concentrated in one water supply / drainage tank, the water level adjusting device can be formed in a compact manner, and it is excellent in workability and can be supplied at low cost.
[0044]
Furthermore, in the present invention, since water management can be performed to minimize the supply of water supplied to each cultivation area as surplus water, agricultural chemicals and fertilizers applied to each cultivation area flow out to the outside together with the water. The amount to be reduced can be reduced, and there is no problem of environmental destruction.
[0045]
In addition, in the present invention, the means for transporting the water by a pump, which has been used in conventional flat irrigation, can be eliminated, and the flow rate can be secured without taking a large gradient of the pipe. It can be done easily and easily, and construction costs can be greatly reduced.
[Brief description of the drawings]
FIG. 1 is a schematic plan view showing an example of a water management system using a water level adjusting apparatus of the present invention.
FIG. 2 is a schematic piping diagram showing an embodiment of a water level adjusting device.
FIG. 3 is a longitudinal sectional view showing a specific shape example of a water level adjusting device.
FIG. 4 is also a plan view.
FIG. 5 is a perspective view of a slide valve used in the water level adjusting device.
FIG. 6 is a schematic piping diagram showing a reference embodiment of a water level adjusting device.
FIG. 7 is a longitudinal sectional view showing a reference shape example of the water level adjusting device.
FIG. 8 is also a plan view.
FIG. 9 is a schematic plan view showing a conventional paddy field structure.
FIG. 10 is a perspective view of a conventional water supply channel.
[Explanation of symbols]
37 ... irrigation line, 38 ... drainage line, 4 ... paddy field, 41 ... shore, 42 ... farming area, 43 ... farm road, 51 ... water supply pipe, 52 ... drainage pipe, 51a, 51b, 52a, 52b ... valve, 6, 6A ... Water level adjusting device, 60 ... Water supply / drainage, 61 ... Cultivation zone water supply / drainage port, 62 ... Water supply / drainage valve, 62H ... Operation rod, 63 ... Water supply / drainage section, 64 ... Drain valve, 64H ... Operation rod, 65 ... Water level adjustment weir, 65H ... Operating rod, 65T ... Cylinder, 66 ... Overflow gate, 70 ... Slide valve, 80 ... Exit bar, 81,82 ... Bill

Claims (4)

In the vicinity of the bottom of the bottomed cylindrical water supply and drainage basin with a cultivation area water supply and drainage port communicating with the cultivation area of the paddy field, a water supply and drainage part connected via a water supply and drainage valve to a water supply pipe provided along the farm road is provided. A water level control device for a paddy field, wherein the water supply / drainage section is provided with a drainage valve that can be opened near the bottom of the water supply / drainage basin and a water level adjustment weir that opens at the top of the water supply / drainage basin.   The paddy field water level adjusting apparatus according to claim 1, wherein the cultivation area water supply / drainage port communicates with the cultivation area through an overflow gate whose height is adjustable. 2. The paddy field according to claim 1 , wherein the water level control weir is formed by a cylindrical body that is connected to the water supply / drainage unit and is fitted to an upper end portion of a pipe opened upward so as to be movable up and down . Water level adjustment device. A paddy field irrigation management system with farm roads on the side edges and divided into multiple cultivated areas by ridges, and water pipes and drain pipes are buried along the farm roads. At least two water level adjusting devices connected to the water supply pipe and the drain pipe are installed, and the water level adjusting device includes a bottomed cylindrical water supply / drainage tank, a cultivation area water supply / drainage port communicating with the cultivation area, A water supply / drainage section connected to the water supply pipe or the drainage pipe, the water supply / drainage section including a water level adjustment weir that is open at the top of the water supply / drainage basin and a drainage valve that is open near the bottom of the water supply / drainage basin And is connected to the water supply pipe via a water supply / drainage valve. By opening the water supply / drainage valve of the water level adjusting device installed on the water supply pipe side, the water supply pipe passes through the water supply / drainage section, The water level that has flowed into the water supply / drainage basin after passing the water level control weir set in the water is supplied to the farming zone from the water supply / drainage port, and the surplus water and rainwater supplied to the farming zone are installed on the drainage pipe side. It flows into the water supply / drainage basin from the cultivated area's water supply / drainage port, passes through the water level control weir whose height is adjusted to the surface water level, is discharged from the water supply / drainage section to the drainage pipe, and opens the drainage valve. And a paddy field water management system characterized in that the earth and sand flowing into the water supply / drainage are discharged .

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