JPH0435565B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is directed to the gate body of a water gate installed across a channel for regulating the flow rate of rivers and lakes, and for water intake and flood control, especially at the upstream mouth. This is a novel invention relating to a door body with a siphon mounted on top of a siphon conduit connecting the top end and a downstream discharge port.

[Conventional technology]

Regarding the gate body with a siphon, there are several inventions and ideas proposed by the applicant himself (for example, "water gate with siphon" (Japanese Patent Laid-Open No. 155412/1983) and (Japanese Patent Laid-Open No. 106008/1989). ).

Conventionally, the amount of water discharged was adjusted by electrically raising and lowering the water gates, but there were problems with staffing and mechanical maintenance, and natural overflow alone without moving parts was not able to cope with the rapid increase in water level on the upstream side. Tsuta solved these problems by developing a water gate with a siphon.

In other words, when the water level on the upstream side rises and the mouth of the siphon pipe is submerged under water due to natural overflow, the air inside the pipe is engulfed by the water flow, rapidly depressurizes, and becomes a siphon flow (transition flow), which rapidly increases the flow rate and generates a large amount of water. Allows for discharge. Even if the water level rises further, expelling all the air in the siphon pipe and entering the pipe flow completely filled with water, the flow rate will still increase (experimentally, compared to natural overflow, the same overflow width, (With the same overflow water depth, approximately 8 times the discharge capacity can be obtained.) It has the advantage of being able to increase or decrease the amount of water discharged by adapting most sensitively to fluctuations in the upstream water level, making it effective in adjusting the water level. ing.

[Problem that the invention seeks to solve]

As mentioned above, in a siphon pipeline, due to the rise in the water level on the upstream side, the forced escape of air in the pipe, and the filling of pipe water, the pipe progresses from natural overflow to a siphon flow (transition flow). The water reaches the current, and the discharge amount increases significantly to achieve the purpose of installing the sluice gate.

By the way, FIG. 9 is a front sectional view showing an example of a typical prior art door body with a siphon.
A is a door body having a welded assembly structure, and a siphon conduit 2a formed by connecting a spout 3a, a top end 4a, and a discharge port 5a is mounted on this door body.

When the water level on the upstream side falls and the upper end of the spout 3a becomes exposed to the water surface, air is sucked in from this part, causing a siphon breaker action, and the pipe flow shifts to a siphon flow (transition flow), causing the water level to drop. If you go further down, it will shift to natural overflow. At this time, rapid air suction continues from the limited narrow gap,
Depending on the location, it can easily cause noise pollution.

In addition, in this type of door body, it is necessary to prevent foreign matter floating near the upstream water surface from entering the door, so dust prevention devices must be installed at all mouths of the siphon-onnar conduit. This work is quite complicated.

FIG. 10 shows another type of conventional door body with a siphon, and since the spout 3b of the siphon pipe 2b is deeply submerged below the water surface on the upstream side, there is no air suction from there as a siphon breaker. Separately, a breaker hole 13b is bored just before the top end 4b.

The feature of this type is that unlike the previous example, there is no risk of floating objects getting mixed in from the upstream side, so there is no need to install a dust prevention device during flow rate adjustment, but the breaker hole is located near the top. Therefore, it is unavoidable that the air noise during intake is abnormally high, and the risk of causing noise pollution remains unresolved.

In order to solve the above problems, the present invention has developed a new door body with a siphon in order to keep the dustproof device for flow rate adjustment to the lightest and smallest, and to keep the air suction noise at the time of the siphon breaker to the smallest. The purpose is to submit the structure of

[Means for solving problems]

The door body with a siphon according to the present invention opens into the siphon conduit near the top end of the siphon conduit in the door body, hangs separately inside the door body, and has a lower end opening near the bottom of the water tank built in the door body. A water conveyance pipe is installed independently, and the upper end is inserted into the pipe near the top of the siphon pipe and installed on the pipe, and the lower end is opened at a desired height inside the water tank with a separate hanging inside the door body. By providing an air supply pipe to the air supply pipe and further providing a discharge channel that opens approximately corresponding to the opening surface of the air supply pipe in the water tank and hangs down to the downstream side, it is possible to intermittent the air supply to the siphon pipe within the door body. Solved the problem.

[Effect]

Since the door body with a siphon of the present invention has the above-described configuration, it achieves the following effects in response to fluctuations in the upstream water level.

When the water level on the upstream side rises and the mouth of the siphon pipe is submerged, and it further rises inside the pipe and reaches near the top, the water overflows inside the pipe and is discharged to the downstream side, and some of it is It hangs down inside the water conduit that opens into the pipeline and enters the water tank inside the door body.

The water tank has a drainage channel that hangs down to the downstream side, so that only the amount of water that flows in flows out.

Fluctuations in the upstream water level and the water level in the water tank can be synchronized by appropriately setting the size of the water tank and the opening area of the water conduit pipe.

An air supply pipe that opens at a desired height protrudes downward into the water tank, and the upper part of this pipe is constructed so as to cover the siphon pipe, and opens near the top of the siphon pipe.

As the water level on the upstream side rises, the overflow of the siphon pipe increases and the discharge port becomes full, so when the air supply from here is cut off, the fluid in the pipe changes to a siphon flow (transition flow), and the amount of water discharged increases. The amount of air increases significantly, and air is sucked in from the tip of the air supply pipe that opens into the space inside the water tank, rises, and is supplied to the pipe from near the top of the pipe.

Furthermore, the water level on the upstream side rises, and the water level in the tank also rises, and when it reaches the air supply pipe opening,
The air flow path is cut off here, and the air supply to the siphon pipe is interrupted, and the flow state of the pipe changes from the siphon flow (transition flow) to the pipe flow, resulting in a large discharge state.

When the water level on the upstream side decreases, the opposite phenomenon progresses, and the air supply from the air supply pipe is restarted, causing the flow state of the siphon pipe to change to pipe flow or siphon flow (transition flow). , transition to natural overflow.

In this way, the intermittent supply of air to the siphon pipe due to water level fluctuations is all caused by the action that occurs within the closed door body.

〔Example〕

Embodiments of the present invention will be described based on the drawings.

FIG. 1 is a front sectional view showing a siphon conduit 2 mounted above a door body 1 made of a welded structure of iron plates. The conduit is formed from a spout 3, a tip 4, and a discharge port 5. A screen bar 6 is attached to the spout 3. A water guide pipe 7, which opens in a part of the siphon pipe and hangs down separately inside the door body, opens near the bottom of a water tank 8 built in the door body, and introduces water from the upstream side. Inside the water tank 8 are energy reducing plates 9A, 9B, 9C...
A protruding wall is installed to reduce the drooping current. A discharge channel 10 for introducing the water to the downstream side is suspended from the upper part of the water tank, and its terminal end coincides with the discharge port of the siphon pipe. The air pipe 1 is placed over the top surface of the siphon pipe 2.
Erection of the upper end of 1. As shown in FIGS. 1 and 2, the air pipe includes an overhead part 12 to the siphon pipe, an air supply port 13 communicating with the top end 4 of the siphon pipe, a hanging pipe 14 hanging separately inside the door body, and a water tank. It consists of an intake port 15 that projects inward.

Figures 3 (front view) and 4 (plan view) show the overall view of the door body with a siphon, and the siphon conduit 2 is divided into a plurality of sections (six channels in this example). The supply of air from the intake port 13 of the air supply pipe 11 to the pipe line is intermittent.

In this example, as shown in both figures and FIG. Although the water conduit pipe 7 is opened toward the upstream side, this device can prevent floating objects from entering.

FIG. 5 is a plan sectional view taken along the line A-A in FIG.
B,..., shows the positional relationship of adjacent discharge channels 10.

Fluctuations in the upstream water level and behavior of the water level and air inside the door body in the embodiment of the present application will be explained based on the drawings.

Figure 6 A and B show that the water level on the upstream side is still low.
In figure A, upstream water flows into the water pipe 7 and flows into the water tank 8.
However, the amount of water that has flowed in flows out. On the other hand, the original flow path, the elevated siphon pipe 2, is in a natural overflow state as shown in Figure B.

Figures 7A and B show that as the water level on the upstream side rises, the overflow water passing through the siphon pipe increases, and as a result, the rear end of the siphon pipe (near the outlet) is filled with water, which enters the siphon flow (transition flow). It is in a state of ivy. Figure A,
As shown by the arrow in Figure B, since the intake of air from the discharge side is closed, air is inhaled only from the bulge-shaped intake port 15 of the air supply pipe 11 that protrudes into the water tank, and the air enters the pipe from near the top of the siphon pipe. Air is supplied to the road.

In FIGS. 8A and 8B, the water level on the upstream side has further increased, and the air supply port 15 is sealed due to the rise in the water level in the water tank.
The siphon pipe becomes full of water without receiving air supply from anywhere, and the flow shifts from the siphon flow (transition flow) to the pipe flow, resulting in a large discharge state.

〔Effect of the invention〕

As described above, the present invention requires the intermittent supply of air to the siphon conduit by the action inside the door body, so that the noise generated with the supply air is not propagated to the outside because it is blocked by the closed structure. Solve pollution problems.

The effect of the second prior art (FIG. 10) of preventing floating matter from entering from the siphon spout can also be maintained.

Furthermore, an advantage unique to this embodiment is that a very small-scale, local dust-proofing device as shown in FIG. 3 is sufficient to prevent floating matter from entering the water tank for the siphon breaker.

[Brief explanation of drawings]

1 and 2 are front sectional views of the embodiment of the present invention, FIG. 3 (front view) and 4 (plan view) show the entire door body, and FIG. 5 is a partial plan sectional view, FIGS. 6A and B (natural overflow), FIGS. 7A and B (siphon transition flow), and FIGS. 8A and B (pipe flow) are front sectional views showing the effects of the embodiment. FIGS. 9 and 10 are front sectional views showing a conventional technique. 1... Door body, 2... Siphon conduit, 3...
(of the siphon pipe) spout, 4... (same) top,
5...(same) discharge port, 7...water pipe, 8...water tank, 10...discharge channel, 11...air supply pipe.

Claims (1)

[Claims] 1 In the door body 1 with a siphon installed above the siphon pipe 2 that connects the upstream spout 3, the top 4, and the downstream discharge port 5, the door body 1 opens into the pipe near the top of the siphon pipe and separates the inside of the door body. A water conduit 7 is provided independently, which hangs down and opens near the bottom of the water tank 8 built into the door body at the lower end, while the upper end is installed on the pipe while communicating with the pipe near the top of the siphon pipe. An air supply pipe 11 is provided which hangs down separately inside the door body and whose lower end opens at a desired height inside the water tank, and an air supply pipe 11 which opens approximately corresponding to the opening surface of the air supply pipe in the water tank and hangs down to the downstream side. A door body with a siphon, characterized in that air supply to the siphon conduit is intermittent within the door body by providing a water channel 10.