JPH045561Y2 - - Google Patents

Description

[Detailed explanation of the invention] (a) Industrial application field This invention regulates the flow rate of rivers and lakes, and is a water gate installed across a channel for water intake and flood control. This relates to a water gate with a siphon that forms a channel.

(b) Prior Art Several proposals have already been made regarding water gates with siphons as extremely efficient technology for regulating the flow rate of rivers and the like. For example, the applicant's own invention, ``Sluice gate with siphon''
Publication No. 155412, Figures 4 A and B and JP-A-1983-
No. 106008, Figure 5 A and B). Conventionally, in order to adjust the amount of water discharged, it was necessary to electrically move the water gate up and down, which caused problems in terms of personnel arrangement and mechanical maintenance.Alternatively, natural overflow without moving parts was sufficient to increase the water level on the upstream side. Although there was a problem that it was not possible to cope with a sudden increase in the amount of water, the invention has the function of suctioning overflow water and discharging it downstream by the siphon action, so the flow velocity in the pipe increases rapidly, making it possible to discharge a large amount of water. Experimentally, compared to a general overflow, it is possible to obtain eight times the discharge capacity with the same overflow width and same overflow water depth. In this way, the sluice gate with a siphon has the effect of quickly responding to fluctuations in the water level on the upstream side and adjusting the discharge amount without having to constantly raise and lower the sluice gate.
figure).

(c) Problems that the invention aims to solve In Fig. 4A, when the upstream water level rises and rubs against the bottom apex 2 of the siphon pipe provided at the spout 1, the overflow water leaves a gap in the siphon pipe. Natural flow. (h1 in Fig. 6) When the water level rises further and the tip 9 of the straight portion of the spout 1 comes into contact with the water surface on the upstream side, the discharge port 3 also becomes full of water, and the tip 9 becomes a siphon-on breaker and the siphon action begins. At this time, a large amount of water is sucked upstream from the spout 1, but along with this suction, a large amount of air is also sucked in, creating air bubbles that collide with the straight part of the tip of the spout 1 and the wall inside the siphon pipe. generates noise and vibration. (Between h1 and h2 in Figure 6) When the water level rises further and reaches the top apex 4 of the siphon pipe, air suction ends and the air bubbles in the siphon pipe disappear, and the pipe becomes full of water and the siphon pipe is filled with water. The flow rate is maximum. (Fig. 6 h2) Then the noise and vibration of the siphon pipeline subsides. Noise becomes a major source of pollution if there are houses near rivers, and repeated vibrations require excessive strength in manufacturing, and the welded parts of the steel plates accumulate metal fatigue, which easily breaks if there are defects. There is a risk.

On the other hand, although this flood gate with a siphon has the advantage of being able to quickly respond to changes in the water level upstream, it also has the potential to suddenly start releasing a large amount of water downstream, potentially causing small to medium-sized floods or accidents downstream before any warnings are reached. As a conventional technique proposed for the purpose of solving this problem, Japanese Patent Application Laid-Open No. 58-1989 shown in Figs. 7 and 8
There is a publication number 86208. As shown in the figure, a large number of partition walls 20 are arranged in the left-right direction inside the gate body, and a siphon 15a is constructed between each partition wall.
The level of 1a is changed for each siphon, and the spout level of the breaker 22 connected to each siphon is also changed.

Specifically, in the rooms 21 divided by the partition walls 20, the siphon bottom plates 16a are installed independently using cross beams so as to form a curved surface, and the siphon bottom plates 16a are installed above the bottom plates 16a at a required interval. Attach the top plate 17a of the siphon, and then attach the bottom plate 16a and the top plate 1.
7a and the partition wall 20, the siphon conduit 1
5a. In addition, the level of the spout 11a of each siphon pipe 15a is changed as shown in the figure, and a hole is provided at the top apex 14a of each siphon pipe 15a, and a breaker 22 is provided extending above the water surface on the upstream side. . Therefore, the timing of the start and end of the siphon action of the siphon pipe 15a separated by the partition wall can be shifted, thereby reducing the simultaneous occurrence of noise and vibration and the sudden release of a large amount of water.

However, it is difficult to imagine that it would be practically possible to manufacture an integral water gate that fits between the weir columns as shown in FIG. In other words, since it is an integrated flood gate,
The position of the skin plate facing perpendicularly to the upstream side must remain constant, and on top of that, the heights of the apexes 14a on the top surface of each siphon pipe are almost aligned, and only the position of the spout 11a is varied up and down. In order to vary the curvature of the upper surface plate 16a and the lower surface plate 17a constituting the siphon, this condition is not satisfied unless the curvatures of the upper surface plate 16a and the lower surface plate 17a that constitute the siphon are completely varied for each siphon. This requires an extremely complicated and cumbersome manufacturing process, and it may not be possible to withstand actual construction.

Alternatively, if the position of the upper surface apex 14a of the siphon pipe 15a is changed and the position of the spout 11a is changed, steel plates of the same curvature may be shifted up and down and welded to the bulkhead, but even in this case, a long integral water gate can be used. Similarly, a large number of rooms 21 in different states are connected and assembled, which is quite cumbersome and structurally undesirable.

Furthermore, even if it were possible to manufacture it, if vibration occurs in any of the siphon pipes in the multiple siphon pipes that are separated by a simple steel plate partition of a single water gate, it will be able to withstand the vibration. Therefore, there is a problem in that it is extremely dangerous unless the strength of the entire gate is set to be sufficiently large.

Furthermore, since a large number of steel pipes are bent and protrude forward from the top apex of each siphon flow path, floating objects on the upstream water surface (driftwood, dust, etc.) may collide with the tip of the siphon breaker and cause damage. , failures such as locking and blocking, which impede control of the siphon action, or resonance, which further promotes vibration, cannot be ignored.

In order to solve the above-mentioned problems, this design minimizes the noise and vibration that occur at the stage of transition to siphon flow, and also smoothes large fluctuations in the downstream water level as smoothly as possible. The purpose is to provide gates that are the easiest to manufacture and have high reliability in terms of strength.

(d) Means for solving the problem The sluice gate with siphon according to this invention is fitted separately between a plurality of weir pillars erected across a waterway,
Each water gate door is provided with a siphon pipe 15 that sucks overflow water from the upper surface by a siphon action and discharges it to the downstream side.
The bottom plate 16 forming the bottom surface of the conduit bent from the mouth 11 is attached in almost the same state, and the top plate 17 forming the top surface of the conduit bent from the spout 11 is fixed at a different height from other adjacent water gate doors. , the pipe apex 14 of the upper surface plate 17 and the tip 1 for each water gate door.
The above-mentioned problem can be solved by forming the siphon breakers formed at 9 at different heights and by varying the cross-sectional area of the spout 11 within a larger range than the cross-sectional area of the outlet 13 of the conduit. Settled.

An example of the configuration of this invention will be explained based on the drawings. FIG. 1 is a side view of the water gate with a siphon of this invention cut at the top apex 14 of the siphon pipe 15 along a vertical plane perpendicular to the river width. .

That is, a separate water gate 10 fitted between a plurality of weir pillars P1, P2, etc. erected across a waterway,
10', 10''... are siphon pipes 15,
15', 15''... are mounted on top of each other.The pipe bottom plate 16 that constitutes the siphon of each water gate door is erected with the same curved plate common throughout the entire length, and the pipe top plate that makes up the siphon 17 is also made of the same curved plate that is common throughout its entire length, and by changing only the distance from the conduit bottom plate 16, the height at which the top apex 14 of the conduit and the tip 19 of the top plate protrude can be changed. The cross-sectional area also varies, but for any water gate, this cross-sectional area is the outlet port 13, 13', 13'' of the pipe, respectively.
It is set larger than the cross-sectional area of .

(e) Function Since the siphon flow path of the present invention has the above-described configuration, when the water level on the upstream side rises and reaches the bottom point of the siphon flow path of each water gate door, it overflows along the bottom of the flow path. The flow begins. At this time, the spatial distance H ₁ between the water level in the channel and the top ends 14, 14', 14''... of the channel,
Since the tops of H ₂ , H ₃ . . . form a step, a corresponding difference occurs between them. When the water level is in the state shown in Figure 2, Figures A and C with the smallest H
In the flow path, the discharge port 13 is already filled with overflow water, so the siphon action begins and the flow velocity rapidly increases, while the sucked air bubbles collide with the pipe wall, causing noise and vibration.

However, in the flow path shown in FIG. 2B, H ₂ is large and the discharge port 13' is not full of water, so natural overflow continues.

As the water level rises further and shifts to the state shown in Figure 3, the breakers 19 are submerged in the flow channels shown in Figure 3 A and C, and there is no longer suction of air, and the siphon effect is at its peak, and a large amount of water continues to be discharged rapidly. . In the flow path shown in FIG. 3B, the breaker 19 is about to touch the water surface, and a large amount of air is sucked in, and the siphon action is about to begin.

Further, when the water level on the upstream side decreases, the siphon breaker 19 installed at the tip of the top apex 14 that was submerged in water separates from the water surface and becomes the state shown in FIG. 3B, and the siphon flow rate decreases. When the water moves away from the water, the state shown in Fig. 2B is reached, the siphon action ends, and natural overflow occurs. For this reason, as the water level rises, three types of flow, namely overflow, siphon flow, and pipe flow, shift sequentially in the siphon flow paths of two or more water gates with a time lag.

The effect of the present invention will be compared with that of the prior art. In the case shown in Fig. 4A and Fig. 5A, the tip 9 of the top plate of the siphon pipe extends horizontally in front of the spout 1 to form a siphon breaker, so that when transitioning to the siphon flow, It is easy to amplify the effect of air bubbles to be sucked and cause noise. Furthermore, since the height of the spout 1 and the height of the siphon breaker 9 are aligned on the same horizontal plane, the siphon flow tends to start all at once over the entire length of the waterway, synchronize, and resonate greatly.

Further, in the prior art shown in FIGS. 7 and 8, a separately bent circular pipe is protruded toward the water surface on the upstream side as a siphon breaker. On the other hand, in the case of the present invention, the cross-sectional area of the spout 11 varies for each water gate door, but is always set larger than the cross-sectional area of the discharge port 13, making it possible to maintain negative pressure in the pipe. It is easy to use, and the upper end surface of the spout acts as a siphon breaker, making it possible to control the siphon flow without adding any special member.

(f) Effect of the invention In the water gate with a siphon according to this invention, as the upstream water level rises, the siphon action starts in the siphon channels of two or more water gates, but the other channels are still in an overflow state. Because of this, the generation of noise and vibration is much smaller than in the conventional technology, where the siphon effect occurs all at once across the entire width of the river. The highest level of vibration occurs during the final stage of the siphon action (just before transitioning to the pipe flow), but since this final stage occurs with a time lag in the siphon flow paths of two or more water gates, the overall Noise and vibration are dispersed, the causes of pollution are largely eliminated, and calculations can be made that are advantageous in terms of manufacturing strength.

Another effect of this invention is that on the upstream side, rapid discharge is performed by the siphon action in the siphon flow path of one of the two or more water gates, while
Adapting to the water level, overflow or pipe flow occurs in other channels, and due to these various changes in flow conditions, it is possible to accommodate a wide range of water level fluctuations without significantly impairing the discharge capacity as a whole. can be followed.

On the downstream side, if there is a sudden rise in the upstream water level, the sudden release of water can be delayed over time to level out the change and give time for response.
It can help prevent floods and accidents.

Figures 7 and 8 were also developed for almost the same purpose.
Unlike the conventional technology shown in the figure, each pipe in each sluice gate is arranged in the same shape, and the above-mentioned variations are made by treating each sluice gate between each dam pillar as one unit and comparing it with other adjacent sluice gates. Since it is provided in between, it has high reliability in terms of strength and does not require an excessive structure.
In addition, it goes without saying that it is easy to construct, but variations in each water gate door do not create a particularly new burden and are not likely to cause any problems in construction.

In the conventional technology, the siphon flow cannot be controlled without adding a siphon breaker that bends and extends forward from the apex of the conduit, making the difference in the difficulty of construction even greater.

On the other hand, with the present invention, the transition to the siphon flow occurs at each water gate and does not propagate to other water gates, so there is no concern that resonance will occur over the entire length. Therefore, it is natural that having the same length is advantageous in terms of strength. In the case of the conventional technology, there is also a concern that floating objects on the upstream side collide with the extended siphon breaker and damage it, or that the siphon breaker becomes blocked and prevents control of the siphon flow.

In other words, there are significant differences between the present invention and this prior art, regardless of whether one focuses on the difficulty of manufacturing, the propagation characteristics of noise and vibration, and the superiority or inferiority of strength.

[Brief explanation of the drawing]

Fig. 1 is a partial side cross section showing an embodiment of this invention, A, B, C in Fig. 2 and A, B, C in Fig. 3 are front sectional views showing the operation of the same embodiment, respectively. 4A and B and 5A and B are a front sectional view and a part of a side sectional view showing different prior art, respectively, FIG. 6 is a chart showing the effects of the prior art, and FIGS. 7 and 8
The figures are a side view and a front view showing yet another conventional technique. 10... Sluice gate door, 11... Spout, 12... Bottom apex, 13... Discharge port, 14... Top apex, 15
...Saifon conduit, 16...Pipe bottom plate, 17
...Pipe top plate.

Claims (1)

[Scope of utility model registration request] In water gates that are installed between multiple weir pillars erected across a waterway so that they can be raised and lowered separately, each water gate has a siphon pipe that sucks overflow water from the top surface using a siphon action and discharges it to the downstream side. A bottom plate 16 having a pipe 15 and forming a pipe bottom surface bent from the spout 11 of the siphon pipe 15 is attached in substantially the same state, and a top plate 17 forming a pipe top surface bent from the spout 11 is attached adjacently. The pipe apex 14 of the upper surface plate 17 and the siphon breaker formed at the tip 19 are formed at different heights for each water gate door,
A water gate with a siphon, characterized in that the cross-sectional area of the spout 11 is varied within a larger range than the cross-sectional area of the discharge port 13 of the conduit.