JPS6357640B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a drainage system for large drainage pump stations, etc., where it is difficult to provide a check valve or a discharge valve, for example.

(Prior art) Conventionally, for example, large drainage pump stations have
As shown in the figure, a suction tank 4 and a discharge tank (for example, a river)
11 is partitioned by an appropriate number (one in this example) of partition walls 2 arranged along the flow direction of the discharged water to form two siphon discharge passages 1, 1'.
The bottom surface of the top of each discharge passage 1, 1' is raised by a predetermined height (H) above the highest water level of the discharge tank 11, and a vacuum breaker valve 13 is provided at the top, and the suction tank 4 and the passage are An impeller 8 rotating around a vertical axis between
A pump 6 is provided. Also, suction tank 4
A partition wall 5 is provided at the pump 6, and a rectifying plate 7 and a guide vane 9 are provided at the pump 6.

(Problems to be Solved by the Invention) In the above configuration, the state shown in FIG. Air pockets are formed. Therefore, water in the discharge tank 11 will not flow back into the suction tank 4.

In this state, if a large amount of rainwater flows into the suction tank 4 due to a typhoon, for example, it must be drained quickly. In this case, if the air pockets at the tops of the siphon discharge passages 1 and 1' are removed using, for example, the vacuum pump 20, the water in the suction tank 4 and the discharge tank 1
1, water in the suction tank 4 flows into the discharge tank 11 using the siphon principle, and drainage can be performed.

However, if the water is drained naturally using the principle of a siphon, the amount of water drained is small, so a large amount of rainwater cannot be drained sufficiently, and if the vacuum pump 20 breaks down, the water cannot be drained.

Therefore, in the past, the vacuum pump 20 was abolished, and the pump 6 was used to forcibly send water into the siphon discharge passages 1 and 1', and the sent water entrained the air in the siphon discharge passages 1 and 1'. I started thinking about eliminating the accumulation.

However, the water that has passed through the guide vanes 9 of the pump 6 is discharged as a swirling flow in the direction of arrow X, where the swirling component given by the rotation of the impeller 8 is large. In other words, it strongly hits one surface of the partition plate 2 that is oriented toward the upstream side of the swirling flow, and hardly hits the other surface of the partition plate 2.

Therefore, the pressure on the upstream side of the swirling flow from the one surface is higher than the pressure on the downstream side of the swirling flow from the other surface.

As a result, the amount of water flowing into the siphon discharge passage 1 located upstream of the swirling flow from the partition plate 2 is
The amount of water flowing into the siphon discharge passage 1', which is located downstream of the partition plate 2 in the swirling flow, is significantly larger than that flowing into the siphon discharge passage 1'.

Therefore, the air in the siphon discharge passage 1 is immediately entrained and becomes a siphon, but the air in the siphon discharge passage 1' is entrained only little by little.
It takes a relatively long time to reach the siphon state.

In view of this fact, it is an object of the present invention to provide a drainage device that can quickly bring a siphon discharge path located downstream of a partition plate into a siphon state.

(Means for Solving the Problems) In order to solve the above problems, the drainage device of the present invention has an appropriate number of passages that communicate the suction tank and the discharge tank arranged along the flow direction of the discharge water. A plurality of siphon discharge passages are formed by dividing the siphon with a partition wall, the level of the top of each discharge passage is made higher than the highest water level of the discharge tank, and a vacuum breaker valve is provided at the top of the siphon, and a In a drainage device equipped with a pump having an impeller rotating about a vertical axis, a communication passage is provided for communicating the tops of at least two of the siphon discharge passages with each other.

(Function) In the above configuration, when the pump is operated, a large amount of the discharge water discharged from the discharge water spouting part as a swirling flow flows into the siphon discharge passage located upstream of the swirling flow from the partition plate. The air in this siphon discharge passage is entrained. At the same time, air in the siphon discharge passage located on the downstream side of the swirling flow from the partition plate is entrained through the communication passage.

Therefore, all of the siphon discharge passages quickly enter the siphon state, and a large amount of water can be discharged.

(Example) The first example of the present invention will be described below with reference to FIGS. 1 and 2.
This will be explained based on the diagram. Note that the same parts as those shown in FIGS. 8 and 9 are given the same numbers, and the description thereof will be omitted. In this embodiment, the tops of the two siphon discharge passages 1 and 1' are communicated with each other via a communication passage 3.

To explain this in detail, water flowing from the suction tanks 4, 4 joins near the suction port of the pump 6 having the impeller 4 rotating in the direction of arrow 9, and is discharged toward the siphon discharge passages 1, 1' as a swirling flow in the direction of the arrow X. The siphon discharge passages 1 and 1' are partitions in which a flow passage whose cross section is closed over the entire circumference from near the discharge port 10 of the pump 6 to the discharge tank 11 is erected along the flow direction _Y2 of discharged water. The siphon discharge passages 1 and 1' are partitioned by a wall 2, and water discharged from the pump 6 flows into these siphon discharge passages 1 and 1'. Further, the siphon discharge passages 1 and 1' have peaks 1a and 1 which are raised in a mountain shape on the way from the pump 6 to the discharge tank 11.
a′ respectively, and these top portions 1a, 1
The insides of a' are communicated with each other by a communication path 3. This communication path 3 is located at the top 1 in one siphon discharge path 1.
One end opening 12a of the communication pipe 12 is inserted and connected to the top of the pipe a, and the other siphon discharge passage 1'
The other end opening 12b of the communicating tube 12 is inserted and connected to the top of the top portion 1a' of the inside.
A vacuum breaker valve 13 is attached in the middle of 2.
This vacuum breaker valve 13 is opened to the top 1 in the siphon discharge passages 1, 1' through the communication pipe 12 by opening the valve.
It has a structure in which the upper parts of a and 1a' are opened to the outside and the inside of the siphon discharge passages 1 and 1' are sealed by the valve closing operation, and even when the vacuum break valve 13 is closed, the siphon discharge passage 1 is closed. , 1' apex 1a, 1
a' are communicated with each other via a communication pipe 12.

To explain the operation of the device configured as described above, when the pump 6 is started, the suction tanks 4, 4 are
The water flowing in from the pump receives a discharge pressure from the pump 6,
The discharge water Q is discharged from the discharge water spouting part of the pump 6 as a swirling flow in the direction of arrow (Upper side in Figure 2)
, the pressure on the upstream side of the swirling flow becomes higher than this one surface, and a large amount of water flows into the siphon discharge passage 1. Thereby, the air within the siphon discharge path 1 is smoothly entrained. At the same time, the air in the siphon discharge passage 1' is also entrained through the communication pipe 12. Since the siphon discharge passage 1' is located on the downstream side of the swirling flow from the partition plate 2, the inflowing water flow is smaller than that of the siphon discharge passage 1. However, since air is entrained through the communication pipe 12, the siphon Almost the same as the discharge path 1, it quickly enters a siphon state and can drain a large amount of water.

The diagram in FIG. 7 is a comparison between experimental results A using the device of the present invention and experimental results B using the conventional device in a model test assuming the large pump shown in FIGS. 1 and 2. In Fig. 7, for example, in the case of a water flow rate of 5 m ³ /min, the conventional device takes approximately 30 minutes to form a siphon after starting the pump.
It used to take 340 seconds, but according to the device of the present invention, it took about 340 seconds.
75 seconds, which shortens the siphon formation time to about 1/5. Furthermore, as shown in FIG. 7, it was found that the smaller the amount of water, the more remarkable the effect of the device of the present invention was.

In the above device, when the operation of the pump 6 is stopped and the siphon formed in the siphon discharge passages 1 and 1' is to be released, the vacuum breaker valve 13 is opened and the siphon discharge passage 1 is released. ，
External air may be introduced into the top portions 1a, 1a' of the pipe 1' through the communication pipe 12, thereby preventing the discharged water Q from flowing back.

In addition, Fig. 3 and Fig. 4 show that the interior of the siphon is divided into three siphon discharge passages 1, 1', 1'' by two partition walls ₂ , 2, which are erected along the flow direction Y2 of the discharged water. This is an example in which the present invention is applied to a divided image.

The one in Fig. 3 shows siphon discharge passages 1, 1',
A communication passage 3' is provided to communicate the top parts 1a, 1a', 1a" in the siphon discharge passage 1, and this communication passage 3' is provided with a communication pipe 1 at the top of the top part 1a in the siphon discharge passage 1.
While inserting and connecting one end opening 14a of 4,
The central opening 14b of the communication pipe 14 is inserted and connected to the top of the top 1a' in the siphon discharge passage 1', and the other end opening of the communication pipe 14 is inserted and connected to the top of the top 1a'' in the siphon discharge passage 1''. 14c is inserted and connected, and the internal air is poorly removed due to the suction action from the siphon discharge path 1 side that quickly entrains and removes the internal air through the communication pipe 14. , 1″ is entrained.

In addition, the one in FIG. 4 has a siphon discharge path 1',
A communication passage 3'' is provided which connects the tops 1a' and 1a'' of the siphon discharge passage 1' with each other.
5, one end opening 15a is inserted and connected, and the other end opening 15b of the communication pipe 15 is inserted and connected to the top of the neck part 1a'' in the siphon discharge path 1''. The siphon has a function of entraining and removing internal air relatively better than passage 1'', and the siphon has poor internal air removal due to the suction action through the communication pipe 15 from the siphon discharge passage 1' side. Air in the discharge passage 1'' is entrained.

In FIG. 4, a vacuum breaker valve 1 similar to the above is provided at the top of the neck portion 1a in the siphon discharge passage 1.
3 is inserted and connected, and in FIGS. 3 and 4, a vacuum breaker valve 13 similar to the above is also provided in the middle of the communication pipes 14 and 15.

Further, FIG. 5 and FIG. 6 show another embodiment of the present invention, which includes a top portion 1a in the siphon discharge passages 1, 1',
A communication hole 16 is formed through the uppermost part of the partition wall 2 corresponding to the uppermost part of the top parts 1a and 1a' as a communication path 3 for communicating the two parts 1a' with each other. And, it exhibits the same effect as the communication pipe 12 shown in FIG. 5 and 6, a vacuum breaker valve 13 similar to the above is inserted and connected to the top of the top portion 1a in the siphon discharge path 1.

In the embodiment shown in FIG. 4, the tops 1a' and 1a'' of the siphon discharge passages 1' and 1'' are made to communicate with each other, but other combinations such as the tops of the siphon discharge passages 1 and 1'' may be used. The present invention can be carried out even if 1a and 1a'' are connected to each other.

Furthermore, in the embodiments of FIGS. 5 and 6,
The communication hole 16 can be formed by cutting out a part of the concrete partition wall 2 or by embedding a pipe or the like.

Furthermore, it goes without saying that the present invention can also be applied to a device in which the interior is divided into four or more siphon discharge passages by three or more partition walls erected along the flow direction of the discharged water.

(Effects of the Invention) As described above, according to the present invention, there is provided a communication passage that communicates the tops of at least two siphon discharge passages among each discharge passage, so that the communication passage is provided on the upstream side of the swirling flow from the partition plate. A large amount of air enters the siphon discharge passage located in the siphon discharge passage and entrains the air in the siphon discharge passage, and the air in the siphon discharge passage is located on the downstream side of the swirling flow from the partition plate so that the air in the siphon discharge passage passes through the communication passage. and was taken away. Therefore, all of the siphon discharge passages quickly enter the siphon state, and a large amount of water can be discharged.

[Brief explanation of drawings]

1 and 2 show an embodiment of the present invention, in which FIG. 1 is a longitudinal sectional view, FIG. 2 is a plan view of the same, and FIG.
5 and 4 are plan views corresponding to FIG. 2 showing other different embodiments of the present invention, FIGS. 5 and 6 show still different embodiments of the present invention, and FIG. 5 is a longitudinal section. Figure 6 is the same plan view, Figure 7 is the same plan view, and Figure 7 is the same plan view.
A using the device of the present invention and B using the conventional device
FIG. 8 is a longitudinal sectional view showing a conventional example, and FIG. 9 is a plan view thereof. 1, 1', 1''...siphon discharge path, 1a, 1
a', 1a''... Top of siphon discharge passage, 2... Partition wall, 3, 3', 3'', 3... Communication path, 4... Suction tank, 6... Pump, 8... Impeller , 11...Discharge tank, 12, 14, 15...Communication pipe, 13...Vacuum breaker valve, 16...Communication hole.

Claims (1)

[Claims] 1. A passage that communicates between the suction tank and the discharge tank is divided by an appropriate number of partition walls arranged along the flow direction of the discharged water to form a plurality of siphon discharge passages, and the level at the top of each discharge passage is discharged. In a drainage system, the water level is set higher than the highest water level of the tank, a vacuum break valve is provided at the top of the tank, and a pump having an impeller rotating around a vertical axis is disposed between the suction tank and the passage. A drainage device characterized in that, among the discharge passages, a communication passage is provided that allows the tops of at least two siphon discharge passages to communicate with each other.