JPH0434111A - Automatic rotary weir - Google Patents

Abstract

PURPOSE:To ensure the operation of a float and stably raise a weir by allowing the inner part of the float of a float chamber to communicate with a downstream side water passage, connecting the float to an interlocking device for vertically raising and lowering the float, and connecting the float to an arm to connect a door body to the float. CONSTITUTION:A door body 19 provided crossing a water passage 17 is fixed to one end of an arm 23, the other end of the arm 23 is fixed to a main shaft 24 rotatably provided in a position lower than the scheduled water level of both walls of the downstream side water passage of the door body 19. A hydrostatic pond 29 communicating with the upper stream side water passage of the door body 19 and a float chamber 20 communicating with the hydrostatic pond 29 and communicating with the downstream side water passage of the door body 19 through a conduit pond 27 are provided on the door body 19 side along the water passage 17. The inner part of the float 37 of the float chamber 30 is allowed to communicate with the downstream side water passage, connected to an interlocking device 51 for vertically raising and lowering the float 37, and connected to an arm 23 through a joint device 43 to interlock the door body 19 with the float 37. Hence, the arm length of the door body 19 can be shortened, and the whole body can be miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an automatic rotating layer (gate) for damming a river or waterway to take in water.

(Prior Art) Gates are usually installed in rivers or waterways in order to keep the upstream water level approximately constant. Conventionally, there are gates that operate using floats, one of which is an automatically operable tenter gate 1 as shown in FIG. In the figure, an arm 4 is fixed in the upstream and downstream directions to a main shaft 3 that is rotatably provided across the upper part of the water channel 2, and an arc-shaped door body 5 centered on the main shaft 3 is attached to the upstream end of the arm 4. It is fixed and arranged so that it can dam the waterway 2. On the other hand, a counterweight 6 is adjustably mounted below near the downstream end of the arm 4.

A still water pond 7 and a float chamber 9 communicating with the still water pond 7 via an overflow weir 8 are provided on the side of the water channel 2. The still water pond 7 has a water inlet 10 in the water channel upstream of the gate l. The float chamber 9 communicates with the gate 1 through a small diameter outlet 11.
It is connected to the downstream waterway. And float chamber 9
The float 12 housed inside is suspended from the upstream end of a float arm I3 fixed to the main shaft 3 so as to extend in the same direction as the arm 4. In addition, the layer table of overflow weir 8 is the outflow port 11.
It is sufficiently large compared to the cross-sectional area of .

Next, the operation of the gate 1 will be explained.

When the water level of the upstream waterway of the gate 1 and the still water pond 7 becomes slightly higher than the top of the overflow weir 8, the top of the overflow weir 8 is made sufficiently large compared to the cross-sectional area of the outlet 11. Therefore, the water level in the float chamber 9 rises, and as a result, the float 12
The gate body 5 rises, the flow rate increases, and the water level in the upstream waterway of the gate 1 becomes lower.

On the other hand, if the water level in the still water pond 7 decreases, the amount of water flowing into the float chamber 9 will decrease and the water level in the float chamber 9 will stop rising, so the gate 1 will remain stationary. Since the effect when the water level of the upstream waterway of gate l decreases is self-evident, a description thereof will be omitted.

By the way, in order to increase the opening/closing accuracy of the gate 1, the flat area of the float 12 can be made smaller, but in this case the buoyancy will be smaller, so firstly, the distance from the main shaft 3 to the gate body 5 (hereinafter referred to as The arm length of the door body 5) is reduced (the resistance torque of the watertight rubber (not shown) attached to the door body 5 is made small, and secondly, the distance from the main shaft 3 to the flow) - 12 distance from the center, that is, the float. It is necessary to increase the length of the arm 13. In other words, it is necessary to increase the ratio of the arm length of the float 12 to the arm length of the door body 5 (hereinafter referred to as arm length ratio).

However, in the conventional technology shown in FIG. Since the speed of the water flow passing below the body 5 is small, there is a problem that the upstream water level cannot be maintained constant unless the door body 5 is opened and closed widely. This means that the arm length ratio of the float 12 must be made extremely small, which is a negative factor in improving the opening/closing accuracy.

Therefore, the present inventor proposed a gate 14 as shown in FIG. 7 (see Japanese Patent Application No. 1-173532). The difference from the conventional gate 1 (see Figure 6) is the float 15.
The inside is divided into a sealed chamber 15a and an upper chamber 15b arranged above the closed chamber 15a, and the inside of the upper chamber 15b is communicated with the downstream water channel of the gate 14 via a flexible communication pipe 16 that penetrates the closed chamber 15a. It is in. As a result, the float 15 moves up and down while the water inside the upper chamber 15b goes in and out, so the acting force acting on the float 15 is independent of the up and down movements of the float 15.
Since the float arm 13 will not disappear unless the water level of the float chamber 9 and the downstream channel change significantly, there is no theoretical restriction on the length of the float arm 13. The arm length can be increased.

The weight and height of the counterweight 6 attached to the downstream end of the arm 4 are adjustable, and the center of gravity of the entire device is diagonally above the upstream side of the main shaft 3 when the gate 14 is fully closed. , in the fully open state, it is arranged to be located diagonally above the downstream side of the main shaft 3. The above things,
In the event of a flood, the flow 1-15 rises while discharging the water inside the upper chamber 15b due to the action of the center of gravity, the lower end of the door body 5 rises into the air, and the gate 14 is fully opened. When the floodwaters subside and the water level of the waterway 2 becomes low, the weight of the sealed chamber 15a at the bottom of the float 15 exposed in the air causes the float 15 to descend and the door body 5 to descend. Therefore, the dam will be raised again.

(Problem to be Solved by the Invention) However, even in the above configuration, the arm length of the door body 5 is still large (the bottom surface of the float chamber 9 is deep,
Therefore, the arm length ratio of the door body 5 and the float 15 does not change much, and the planar area of the float 15 is still large (
However, the problem of requiring installation space remains.

In addition to the fact that the arm length ratio between the door body 5 and the float 15 is small, the fact that the float 15 is suspended directly from the float arm 13 causes the float 15 to displace upward and downstream as it moves up and down. Therefore, the gap between the float 15 in the float chamber 9 and the float 15 must be widened, and therefore the force acting on the float 15 does not decrease easily. Since frictional resistance changes to dynamic frictional resistance and decreases, the door body 5 moves excessively (this means that when the flow rate is low, the door body 5 constantly repeats opening and closing, and the water level is not constant. There was a problem.

SUMMARY OF THE INVENTION An object of the present invention is to provide an automatic rotating weir that can ensure stable soil filling by ensuring the operation of a float that operates a gate body.

(Means for Solving the Problems) In order to achieve the above object, the present invention fixes a door provided across a waterway to one end of an arm, and fixes the other end of the arm to the downstream side of the door. A stilling pond fixed to a main shaft rotatably disposed at a position lower than the planned water level on both walls of the waterway and communicating with the upstream waterway of the gate body, and a still water reservoir communicating with the still water reservoir and communicating with the downstream waterway of the gate body. A float chamber communicating through a water conduit is provided on the side of the door body along the waterway, and an interlocking device that vertically raises and lowers the float by communicating the inside of the float arranged in the float chamber with the downstream waterway. and the arm is connected to the interlocking device via a connecting device, so that the door body is interlocked with the float.

Further, the counterweight may be attached to the interlocking device via a coupling device, and the float may be held by a guide device so as not to swing laterally when going up and down.

(Function) Since the present invention is configured as described above, the main shaft is supported at a position below the planned water level, so the arm length of the door body can be significantly reduced, and the resistance when the door body is operated is reduced. Torque becomes smaller. In addition, since the interlocking device can be installed at a different location from the main shaft, the length of the float arm can be increased just by slightly digging into the bottom of the float chamber. The length ratio can be significantly increased.

In addition, since the float can be moved up and down vertically within the float chamber by the interlocking device, the planar position of the float is determined, eliminating the need for extra clearance between the float and the float chamber in the upstream and downstream directions, and reducing the planar area of the float. Not only can it be made smaller, but its water area can also be made smaller. Therefore, when the float moves slightly up and down, the water surface in the float chamber moves significantly in the opposite direction to the float, the acting force acting on the float disappears, and the door body no longer moves in vain, resulting in efficient operation.

Furthermore, although a float must necessarily straddle water and air, the interlocking device can be installed above the water surface using a connecting device. Furthermore, since the counterweight is also attached via a connecting device, it does not obstruct the flow of running water.

[Example] Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 3, the waterway 17 is provided with a gate 18 for blocking the flow, and the gate body 19 that crosses the waterway 17 has vertical girders 20 made of thick plates arranged at both ends thereof. , door body 1
On the downstream side of 9 is a torsion girder 21 that forms a box-shaped cross section that is integrated with the door body 19 at an intermediate height position and whose both ends are fixed to the longitudinal girders 20, and the lower end of the door body 19. A horizontal girder 22 (see Fig. 1), which is fixed nearby and whose both ends are also fixed to the longitudinal girder 20, is assembled. The arms 23 on the downstream side of the longitudinal girders 20 on both sides are located at the intermediate height of f.
．． 23 is fixed.

The direction of the arm 23 is as follows when the gate 18 is fully closed.
is made horizontal, and the tip of a main shaft 24 having handles on both sides is loosely fitted from the outside into a hole formed at its downstream end, and both are connected by a spring pin 25, and one main shaft 23 is connected to a water channel. Main bearing 26 buried in the wall of 17
The other main shaft 24 is rotatably supported by a main bearing 26 buried in the wall of the water channel 17, and passes through the water channel 17, crossing parallel water guide basins 27 to be described later. It is rotatably supported by an auxiliary bearing 28 (see FIG. 2) embedded in the wall of the main body. In addition, a water channel 1 is provided on the side of the door body 19.
A still water pond 29 is provided across the wall 7, and a float chamber 30 and a water guide pond 27 are provided in this order toward the downstream side. The still water pond 29 communicates with the upstream waterway of the gate 18 through a water inlet 31 bored in the wall, and the still water reservoir 29 communicates with the float chamber 30 through an overflow weir 32. Further, the float chamber 3o communicates with the water guide section 27 via a small diameter outflow pipe 33 arranged at the bottom, and also communicates with the water guide section 27.
7 is communicated with the downstream water channel of the gate 18 via a water inlet 34 bored in the wall of the water channel 17 (see FIG. 1.2).

Next, the configuration of the overflow weir 32 will be explained. As shown in FIG. 2, a tank-shaped water injection tank 35 with an upper opening in the still water pond 29 is arranged with the height of its upper end appropriately lower than the planned water level at which a predetermined fill-in soil should be filled. A water injection pipe 36 is connected to the lower part of the water injection tank 35 via a square screw, and the other end of the water injection pipe 36 is opened at a position lower than the lower end of the float 37 in the float chamber 30 in its lowest state. The vicinity of the inlet 35a of the water tank 35 is surrounded by a cylindrical dustproof and waveproof tube 38. In addition, the circumference of the water injection tank 35 is the same as that of the outflow pipe 3.
It is sufficiently larger than the cross section of No. 3, and the water injection tank No. 35
The water area of the water tank 35 is made as small as possible by allowing water to overflow from the song.

The float 37 provided in the float chamber 30 has a sealed part 37a formed at its lower part, a water guide part 37b above the sealed part 37a, and a vent hole 37c formed in the top plate.

In addition, a pair of guide rods 39, 39, which are vertically protruded from the bottom of the upstream wall center and near the downstream wall center of the two funnel chamber 30, are fixed to the bottom surface of the two funnel chamber 30, respectively.
is inserted into a guide vibe 40 fixed to the float 37. Therefore, the float 37 moves up and down along the guide rod 39, and the position of the float 37 in the float chamber 30 is determined, so that the distance between the float 37 and the float 37 is fixed. The gap is made as small as possible. In addition, a water guide hole 41 that opens at the lower end of the water guide section 37b passes through the sealing part 37a and is connected to a flexible water guide pipe 42 of sufficient length at the lower end of the float 37 so that the float 37 can move up and down without any trouble. The tip of the water guide pipe 42 penetrates the wall of the float chamber 3o and opens into the water guide section 37. Note that the sizes of the outflow pipe 33 and the water conduit pipe 42 are determined so that the opening/closing speed of the gate 18 is appropriate.

The main shaft 24 that traverses the interior of the water guide section 27 described above has a link 44 of a connecting device 43 fixed to its central position, and a connecting member 46 rotatably connected to its tip via a lower connecting pin 45. There is. Further, above the main shaft 24 that traverses inside the water guide section 27, a lower shaft 48 is rotatably supported in parallel to the main shaft 24 by a pair of pillars 47 and 47 erected on the upper surface of the wall of the water guide section 27. It is provided.

On this lower shaft 48, a pair of lower arms 49.4 are located inside the pair of support columns 47.47 and extend in the upstream and downstream directions.
9 is fixed, and the upper end portion of the connecting member 46 is rotatably connected to the downstream end of the lower arm 49 via an upper connecting pin 50 that connects the pair of lower arms 49 and 49. . In this configuration, the main shaft 24, the lower connecting pin 45 and the upper connecting pin 50 of the connecting device 43, and the lower shaft 48
The lines connecting them form a parallelogram.

Next, the interlocking device 51 will be explained. An upper shaft 52 is horizontally rotatably provided above the lower shaft 48 and is pivotally supported by a support 47, and a pair of upper arms 53 extend upstream from the upper shaft 52.
．． 53 is fixed. A vertical member 56 is connected to the upstream end of the lower arm 49 and the end of the upper arm 53 via a lower support pin 54 and an upper support pin 55, respectively.

A lower rail 57 and an upper rail 58 protrude from the vertical member 56 at right angles toward the upstream side, and the float 37 is supported via a connecting member 60 having a roller 59 loosely fitted therebetween. In this configuration, a line connecting lower shaft 48, lower support pin 54, upper support pin 55, and upper shaft 52 forms a parallelogram.

Further, a branch arm 61 protrudes below the lower arm 49 on the downstream side of the lower arm 49 fixed to the lower shaft 48 which is pivotally supported by the column 47.
is installed. The position of the counterweight 62 when viewed from the lower shaft 48 is from the main shaft 24 of the gate 18 to the gate 1.
8's center of gravity is now one direction higher than the exact opposite direction. Note that the tip of the guide rod 39 described above is fixed to a frame 63 supported by the support column 47 and attached on the upstream side. Further, a stopper 64 is fixed to the side wall of the water channel 17 so as to support the arm 23 at a position adjacent to the downstream side thereof when the arm 23 of the gate 18 is in an upright state.

Next, the details of the configuration will be explained. First, a planned water level to be stopped at a predetermined dam is set, and an upper limit water level is set above it within a practically allowable limit, and the gate 18 is opened so that the downstream water level is the planned water level and the upstream water level is the upper limit water level. At the same time, the float chamber 30 and the water guide portion 37b of the float 37
so that the gate 18 closes when the water levels within are equal.
The weight of the counterweight 62 is adjusted, and the planar area of the float 37 is made large enough so that the gate 18 opens when the water level in the float chamber 30 reaches the upper limit water level.

Since the weight of the counterweight 62 and the horizontal position of the counterweight 62 in the state where the downstream water level is the planned water level and the upstream water level is the upper limit water level have been determined upstream, next we will discuss the height of the counterweight 62 in this state. Give an explanation. Prior to determining this height, first, at each opening below the above-mentioned opening, the height of the entire center of gravity should be as high as possible within the limit that allows the gate 18 to open reliably (although The height of the counterweight 62 is determined so that the center of gravity of the vehicle is located at such a position.

In addition, I would like to add a supplement to the problem of the overall center of gravity position. In the present invention, as described above, the gate 18 and the interlocking device 5
Since the first class is distributed and supported on three axes, the term "center of gravity" may not seem appropriate, but since the whole rotates as one, mechanically speaking, all parts can be considered to be supported by the lower shaft 48 of the interlocking device 51. Therefore, assuming that all of the gate 18 etc. are supported directly on the lower end, if the weight and center of gravity of the portion excluding the counterweight 62 are selected in advance, the weight and position of the counterweight 62 can be set. can be easily determined based on the above structural requirements.

The height of the upper end of the sealed portion 37a of the float 37 is
For the gate 18 located at the most upstream position, the sealing part 37
The sum of the torque in the closing direction caused by exposing a part of the gate 18 in the air and the frictional resistance torque of the gate 18 is suitably smaller than the torque in the opening direction due to the eccentric force of the gate 18, and multiple When installing gates 18, the gates should be made smaller in order as they go downstream.

In addition, regarding the inflow means to the float chamber 30 and the structure for communicating with the downstream waterway, there is a structure in which a water pipe is arranged to enable communication between the still water pond 29 and the water guiding pond 27 (Japanese Patent Application No. 1983-
326668) may be combined. In addition, by making the center of gravity of the entire rotation group higher than the axis, the gate 1
Although the gate 8 is configured to be fully opened, if there is a spillway upstream, it is better to have a configuration in which the gate 18 is not fully opened during floods.

Next, the action will be explained.

First, the graph in Figure 5 shows the relationship between the gate opening degree and the water level. In the above configuration, the downstream water level determined by the planar area of the float 37 and the weight and position of the counterweight 62 is equal to the planned water level. The state in which the upstream water level reaches the upper limit water level is referred to as pattern (2), the fully open state of the gate 18 is referred to as pattern (e), and the state intermediate between pattern I and pattern m is referred to as pattern (2). Also, the curve ■ is
The downstream water level for each opening angle of the gate is shown, and the curve (2) shows the water level in the float chamber 30 where the gate 18 is stationary. The difference in water level between the inside and outside of the float 37, which is necessary for the torque to be balanced, can be understood by comparing it with the curve (2).

As already explained in the above configuration, in pattern (2), when the water level in the float chamber 30 is at a height intermediate between the upstream and downstream water levels, the closing direction torque due to the eccentricity of its own weight and the float If the torque in the opening direction due to buoyancy is balanced and the water level in the float chamber 30 becomes equal to the upstream water level, the gate 18 will open (the planar area of the float 37 is determined as such, but the opening of the gate 18 is Of course, the resistance torque in the direction and the closing direction are equal, so in other words, in the above configuration, the water level in the float chamber 30 is equal to the upstream water level,
When the water level difference between the inside and outside of the float 37 becomes equal to the water level difference between the upstream and downstream sides of the gate 18, it is expected that the float 37 will generate a torque that is twice the resistance torque of the gate 18. This is the same for pattern ■, but in pattern ■, as shown in Figure 5,
As the flow rate decreases, the water level difference between the upstream and downstream sides, which is the source of the buoyancy of the float 37, increases.On the other hand, there is a slight increase in the resistance torque due to the increase in the water pressure difference between the upstream and downstream areas acting on the gate 18. Since the resistance torque due to its own weight is large, there is more room in the planar area of the float 37 in pattern (2) than in pattern (m), and when the water level in the float chamber 30 becomes equal to the upstream water level, buoyancy acts on the float 37 and the gate 18 When the water level opens and becomes equal to the downstream water level, the buoyant force acting on the float 37 disappears and the gate 18 closes due to the eccentric force of its own weight.

On the other hand, the water level difference between the upper and downstream parts of the outflow pipe 33 and the float chamber 3
Since the passing flow rate at 0 differs depending on the gate opening degree, the upstream water level when the gate 18 is in a stationary state varies somewhat depending on the flow rate. However, since the circumference of the water injection tank 35 is made sufficiently larger than the cross section of the outflow pipe 33,
The overflow level itself on the water injection tank 35 is extremely small.
The difference in upstream water level based on the difference in overflow level is so small that it does not pose any problem in practice. Also, given the above configuration, the gate 18 naturally opens or closes as the flow rate increases or decreases, but the amount of inflow into the float chamber 30 must increase when it opens and decrease when it closes, so this also causes the upstream water level to change slightly. It becomes a factor. However, as mentioned above, the circumference of the water injection tank 35 is large (the overflow water source is extremely small), so as soon as the upstream water level starts to rise or fall, the float chamber 35
The amount of inflow into the interior increases or decreases. In addition, the horizontal rails 57, 58 and rollers 59 of the interlocking device 51 are used to prevent the float 37 from being displaced in the upward and downstream directions, and the gap in the float chamber 30 is made as small as possible, so the water level in the float chamber 30 is also reduced. The float 37 moves up and down immediately in response to increases and decreases in flowing water.
The gate 18 follows without delay. Therefore, except in the case of a sudden flood, the change in the amount of water flowing into the float chamber 30 is slight, and therefore the change in the upstream water level is extremely small and can be considered almost constant.

Next, the function of the water guide portion 37b of the float 37 will be explained. First, when the water level difference between the upstream and downstream sides of the water channel 17 is small, the flow velocity of the water flow passing below the gate body 19 is small, so
Hydraulically, the door body 19 is required to move up and down significantly even if the increase or decrease in flow rate is extremely small. For this reason, the door body 19
In addition to increasing the arm length ratio of float 37,
The interior of the water guide portion 37b within the float 37 is communicated with the downstream waterway. Therefore, if the movement of the door body 19 is insufficient and the water level inside the float chamber 30 and in the downstream waterway does not change, the difference in water level between the inside and outside of the float 37 will not change, so the operating force acting on the float 37 will not disappear. The float 37 can move up and down. Therefore, the movement of the door body 19 becomes agile, and the arm 23 of the door body 19 can be shortened and the rotation angle of the arm 23 can be increased.

Next, the effect of providing the arm 23 of the gate 18 underwater will be explained. For the above reasons, gate 18
The distance from the main axis to the door body 19 is shortened, and the float 3
7 can be increased, and by doing so, the resistance torque of the watertight rubber attached to the door body 19 is reduced, and as a result, the operating torque of the float 37 is increased, and the float 37 can be made smaller. From this perspective, the main axis 24
Since the arm 23 is installed underwater, it is possible to make the length of the arm 23 extremely small, and the length is only about the height of the float door body 19. Therefore, the planar area of the float 37 is reduced ( Since the gate 18 moves very little, the flow rate is large (it does not change and the upstream water level remains stable).

A supplementary explanation will be given regarding the necessity for the gate 18 to move in small increments. In recent years, field irrigation has become popular, and joint projects with waterworks and agricultural water are being carried out, but in these cases, the flow rate in winter is extremely small compared to the cross section of the waterway, and the opening degree of gate 18 is 2 cm. There are things that are just inside and outside. In the conventional technology, in such a case, the gate 18 fluctuates greatly as described above, so the flow rate changes dramatically and the upstream water level is not stable and constantly fluctuates. The reason for this is that the coefficient of dynamic friction is smaller than the coefficient of static friction.
On the other hand, the operating force acting on the float 37 does not disappear at the position where the float 37 is slightly raised or lowered, and furthermore, because the arm length ratio of the door body 19 and the float 37 is small, This is because the door body 19 opens and closes with increased width.

From the above viewpoint, in the present invention, the arm length of the door body 19 is minimized by providing the main shaft 24 below the water surface as described above, and on the other hand, water is introduced into the float 37 so that the bottom surface of the float chamber 30 By digging deeply, the arm length of the float 37 is made as large as possible. Therefore, although it is a matter of comparison, if the door body 19 moves up and down slightly, the float 37 moves greatly. Since the gap between the door body 19 and the float 37 is made as small as possible, when the door body 19 moves up and down slightly, the water surface in the float chamber 30 moves in the opposite direction to the float 37, creating a large braking force on the float 37. Since the arm length of the float 37 is increased, a large braking torque is applied, and therefore the movement of the door body 19 is extremely small. Since the gap is made as small as possible, the gate 18 moves rapidly.

Therefore, no matter how small the movement of the gate 18 is, it is impossible for the upstream water level to change significantly due to insufficient movement of the gate 18.

In addition, the above planned water level is, to be precise, a planning water level, and is adjusted by artificially adjusting the amount of water intake, so it can only be used in the event of a drought that occurs once every few years. Although it is said that this does not happen, in reality, Gatahiki water is literally carried out, and at the peak of water demand, it is common for the water level to be raised to the planned water level every year. Therefore, if the flow rate decreases after the downstream water level reaches the planned water level, the gate 18 must immediately close automatically to ensure the upstream water level. Even in such a case, the present invention is configured such that in the state of pattern m, when the internal and external water levels of the float 37 become equal, the gate 18 is closed by the action of its own weight. In pattern m, the center of gravity is located on the upstream side and is easier to close, so there is no problem.

Further, since the height of the upper end of the water injection tank 35 is set slightly lower than the planned water level by 1, the upstream water level is approximately equal to the planned water level in most areas of pattern H. However, as the downstream water level approaches the planned water level, the upstream water level gradually becomes higher than the planned water level, and when the downstream water level reaches the planned water level, the upstream water level becomes the upper limit water level.

Next, the action of opening the gate 18 due to flooding will be explained. If a flood occurs and the flow rate increases at S until the opening degree of pattern ■, the downstream water level will also rise, but the upstream water level will increase even more, so the difference in water level between upstream and downstream will be larger than in pattern ■. Therefore, even if a flood occurs and the flow rate exceeds the planned flow rate, it is impossible for the opening degree of the gate 18 to remain in pattern ■, and in the event of a flood, the gate 18 will gradually open (Fig. 4g) However, as the downstream water level rises, it is inevitable that the upstream water level will rise above the upper limit water level. However, as the gate 18 opens, the center of gravity of its own weight approaches directly above the shaft, so the difference in water level between upstream and downstream gradually decreases. begins to open spontaneously due to the action of the center of gravity. Hereinafter, this state will be referred to as pattern IV, and the rotation angle of the gate 18 from pattern III to pattern ■V will be explained as described above in pattern 1]
Since the center of gravity is set as high as possible within the limit in which the gate 18 can be opened at any opening angle of is significantly higher than the planned water level (it will not be).

According to the design standards, the free height of the waterway 17, that is, the height from the water surface to the top of the waterway side wall, is required to be approximately 20 to 30 cm at the planned water level.
In the case of planned flood level, up to 10 cm is allowed. Therefore, the planar area of the float 37 can normally be determined based on the pattern (2) as explained in the above configuration. However, if the gate 18 is installed very close to the downstream and the dam is raised due to special social circumstances, the rotation angle between patterns III and IV will be too large due to the low center of gravity. If the upstream water level is high (it cannot be said that it will never become too high), in such a case, pattern ■
This problem can be easily solved by increasing the planar area of the float 37 based on the water level of v.

In addition, after the gate opening degree is wider than in pattern ■, it cannot be automatically closed immediately even if the flow rate decreases and the downstream water level falls; Normally, water is not taken for about , - days.

However, if it is absolutely necessary to restart soil filling immediately, once the flow rate is reduced at the water intake from the river or the like and the sealed portion 37a of the float 37 is exposed in the air, the soil filling can be restarted immediately.

Next, the effect after pattern (2) will be explained.

In pattern (2), when the gate 18 starts to open spontaneously, the water in the water guide portion 37b of the float 37 flows into the water guide pipe 4.
2, and the water in the float chamber 30 is discharged through the water tank 3.
5 and the outflow pipe port 33, and the rising of the float 37 further rotates the door body 19 by the coupling device 43. Since the water movement described above does not occur instantaneously, the gate 18 continues to open at a moderate speed, and when the arm 23 becomes vertical, the heights of the upper and lower ends of the door body 19 become equal, and the arm 23 is pressed against the stopper 64 and becomes stationary. Particularly, in the final stage, a part of the sealed portion 37a of the float 37 is exposed in the air as described in the above configuration, and the torque in the closing direction is appropriately smaller than that in the opening direction, so that rotation is difficult. The speed is particularly small, and the arm 23 quietly contacts the stopper 64. This state will be referred to as pattern V.

The time from pattern ■ to pattern ■ is not instantaneous, but it is extremely short. Therefore, the water level in pattern V is equal to f in pattern (2), but even if the flow rate increases further and the water level rises, the stopper 64 maintains a stationary state.

The posture of the door body 19 in pattern V is such that the projected area seen from the upstream side is small, the arm 23 is in a vertical state, and the water pressure applied from the upstream side can be stopped by the stopper 64, making it a stable posture. be.

Next, we will explain the effect of restarting soil burying after the floodwaters have subsided. When the flow rate decreases and the water level becomes lower than the water level shown in pattern ■, Gu 1-18 begins to close, and when it reaches the opening degree of pattern ■, it will automatically close due to the action of the center of gravity and will be buried again. is started. At this time, water enters the float 37 and water in the float chamber 30 is discharged, so the speed of the closing movement is determined by these actions.

Next, as described above, the water level of the water channel when the opening degree of the gate 18 reaches the state of pattern (2) and the spontaneous closing operation is started will be considered. As mentioned above, after the goo 18 starts to open in pattern IV, it is necessary that the sealed portion 37a is not exposed to the air for a while. This is because, in pattern (2), the action of the center of gravity is equal to the frictional resistance of the gate 18, f, so that if the sealed portion 37a is exposed in the air, it will not be possible to continue the opening movement. In the present invention, as described above, in pattern (2), the upper end of the sealed portion 37a is submerged in water. Also, pattern I
Even between pattern I and pattern I■, if the upper end of the sealing part 37a is higher than the downstream water level, the difference in water level between the upstream and downstream will increase accordingly, which is undesirable. When the gate 18 is opened, the upper end of the sealed portion 18a must be below the downstream water level. On the other hand, since the sealed portion 37a needs to be exposed in the air when the gate 18 closes, the water level of the waterway needs to be appropriately lower than the planned water level in order for the gate 18 to start closing spontaneously.

However, as already explained, in the event of a flood, there is usually no need to rush to divert water, that is, to bury soil, and if there is a special situation that requires it to be done quickly, the water intake gate should be temporarily closed or If the most upstream gate 18 is closed artificially, the flow rate will temporarily decrease and the water level on the downstream side of the waterway will drop, so the gates 18 placed downstream can be automatically filled with soil one after another. .

Note that when multiple gates 18 are installed in the same waterway, if the downstream gate 18 closes before the upstream gate 18, the water level of the waterway 17 will be raised by the downstream gate 18 and the upstream gate 18 will close. There is a risk that the water level at the gate 18 position will not drop and the upstream gates 18 will operate in the same way as during a flood, but this can be resolved by sequentially lowering the height of the upper end of the sealing part 37a as the downstream side becomes lower. Ru.

Next, the mechanical action of the gate 18 will be supplemented. Since the torsion girder 21 is provided on the back side of the door body 19, even if the float chamber 30 and the interlocking device 51 are installed on one side of the door body 19, the left and right twisting of the door body 19 due to this load is eliminated. When installing the left and right pair of arms 23, the angles are the same and no twist is applied to the arms 23, so arm 2
The thickness of the board 3 can be made thinner so that it can be installed under running water. In addition, door body 1
A strong water pressure is applied to the lower edge of 9, but since the horizontal girder 22 is fixed and strong, the stress can be reduced.

(Effects of the Invention) Since the present invention is constructed as described above, the arm length of the door body can be shortened, and by using the interlocking device, the gap between the float and the float chamber can be reduced. Since the gate body and the float are linked by a connecting device, the movement of the gate is extremely smooth and stable dam raising can be performed. In addition, not only can the entire gate be made smaller and more economical, but most of the gate body is always hidden within the waterway, so it does not take up much space and does not spoil the scenery.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a longitudinal section of a gate in a waterway according to an embodiment of the present invention, FIG. 2 is a side view showing a longitudinal section of a still water pond, etc. on the side of the gate of the embodiment, and FIG. 3 is a side view showing a longitudinal section of a gate according to the embodiment. FIG. 4 is a plan view of the example gate, FIG. 4 is a side view showing the operation of the example gate, FIG. 5 is a graph showing the relationship between the opening degree of the example gate and the water level, and FIG. 6 is a graph of the conventional gate. 7 is a side sectional view of another conventional gate. 17... Waterway 19... Door body 23... Arm 24... Main shaft 29... Still water pond 30... Float chamber 37... Float 43... Connecting device 5J... Interlocking device

Claims (1)

[Claims] (1) A gate provided across the waterway is fixed to one end of an arm, and the other end of the arm is rotatably arranged at a position lower than the planned water level of both walls of the waterway on the downstream side of the door. A still water reservoir that is fixed to the main shaft and communicates with the upstream water channel of the door body, and a float chamber that communicates with the still water reservoir and communicates with the downstream water channel of the door body via the water guide basin are attached to the door body along the water channel. installed on the side,
The interior of the float arranged in the float chamber is communicated with the downstream waterway, the float is connected to an interlocking device that vertically raises and lowers the float, the arm is connected to the interlocking device via a connecting device, and the door body is connected to the An automatic rotating weir characterized by being linked with a float.