JP2020084674A - Drainage device - Google Patents

Abstract

To provide a drainage device that saves installation space and enables continuous operation.SOLUTION: The drainage device that drains liquid stored in a drainage storage part using negative pressure comprises: a lower tank; an upper tank that is provided above the lower tank and is connected so as to open/close the communication with an internal space of the lower tank through an opening/closing valve; and a vacuum pump that is connected to the upper tank, wherein the upper tank has a pressure switch for controlling drive of the vacuum pump, and a drain pipe connection part that connects piping extending from the drainage storage part, and the lower tank is configured to include a water level sensor that detects a water level of drainage stored in the internal space, a drainage valve for discharging the drainage stored in the internal space, and an atmosphere release valve that allows the internal space to communicate with an external space.SELECTED DRAWING: Figure 1

Description

The present invention relates to a drainage device, and more particularly, to a drainage device using a vacuum pump.

2. Description of the Related Art Conventionally, there is known a vacuum type drainage device that sucks sewage and the like by a pressure difference from the atmospheric pressure and drains it by keeping a negative pressure inside the pipe using a vacuum pump. For example, a vacuum pump holds the inside of the drainage pipe in a substantially negative vacuum state, and in this state a negative pressure is applied to the wastewater by opening the valve, and the pressure difference is used to suck the wastewater into the vacuum tank and store it. It is known that the waste water is drained after that (Patent Document 1).

JP, 2013-7211, A

However, in the above-described drainage device, when the waste water stored in the vacuum tank is discharged to the outside, the pressure in the vacuum tank and the pipe becomes atmospheric pressure, and it takes time to return to the vacuum state, and the waste water is sucked during this time. Since it is not possible, drainage operation will be intermittent. Therefore, in the case of performing continuous operation using such a drainage device, it is possible to install, for example, two or more vacuum tanks. However, in order to simply control the continuous operation, it is necessary to provide a vacuum pump for each vacuum tank, which leads to an increase in installation space and cost.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a drainage device that can save installation space and can be continuously operated.

As a configuration of a drainage device for solving the above problems, a drainage device for draining a liquid stored in a drainage storage unit by using negative pressure, which is provided in a lower tank and above the lower tank, and is opened and closed. An upper tank connected to the inner space of the lower tank via a valve so as to be able to open and close, and a vacuum pump connected to the upper tank, and the upper tank has a pressure switch for controlling the drive of the vacuum pump, The lower tank is provided with a drainage pipe connecting part to which a pipe extending from the drainage storage part is connected, and the lower tank is a water level sensor for detecting the water level of the drainage stored in the internal space, and the drainage for discharging the drainage stored in the internal space. A valve and an atmosphere release valve that allows the internal space to communicate with the external space are provided.
According to this configuration, the installation space can be saved and the drainage device can be continuously operated.
As another configuration of the drainage device, the volume of the upper tank may be larger than that of the lower tank.

It is a schematic structure figure showing one embodiment of a drainage device. It is sectional drawing which shows the connection part to the upper/lower tank of a pressure sensor, a water level sensor, and a bypass pipe. It is a figure which shows the operating state of a drainage device.

Hereinafter, the present invention will be described in detail through embodiments of the invention, but the following embodiments do not limit the invention according to the claims, and all combinations of the features described in the embodiments are the inventions. It is not always essential to the solving means, and includes configurations that are selectively adopted.

FIG. 1 is a schematic configuration diagram showing an embodiment of a drainage device. The drainage device according to the present embodiment stores, for example, a liquid such as sewage generated from a water supply facility such as a toilet, a wash basin or a kitchen of a restaurant, in a drainage storage unit provided in the water supply facility, A device for discharging a drainage using a vacuum, which is generally a lower tank 2 and an upper tank 4 provided above the lower tank 2 and connected to the lower tank 2 via a connecting pipe 6. And a vacuum pump 8 for reducing the pressure in the internal space of the lower tank 2 and the upper tank 4 connected by the connecting pipe 6.

The lower tank 2 and the upper tank 4 are so-called pressure vessels having a predetermined strength. When the upper tank 4 is in a predetermined negative pressure state and the lower tank 2 is in the atmospheric pressure state, the lower tank 2 and the upper tank 4 open the communication opening/closing valve 16 and the bypass valve 30 to allow the upper tank 4 and the lower tank 2 to communicate with each other. The respective volumes are set such that the pressure when the upper tank 4 and the lower tank 2 are integrated together is, for example, 60% or more of a predetermined negative pressure state. That is, the volume of the upper tank 4 is set to be larger than the volume of the lower tank 2. Note that the relationship between the volumes of the upper tank 4 and the lower tank 2 is not limited to 60% or more and can be changed as appropriate as long as the volume of the upper tank 4 is larger than the volume of the lower tank 2. The predetermined negative pressure state in the present embodiment refers to the pressure when the driving of the vacuum pump 8 is stopped, that is, the pressure detected by the pressure sensor 20 described later. 1 and 3 to be described later, the sizes of the lower tank 2 and the upper tank 4 are shown to be the same, but this shows the existence of the lower tank 2 and the upper tank 4 in the system. However, the size and shape are not specified based on the figure.

The lower tank 2 is provided with a drainage valve 10 for discharging the wastewater stored therein, a water level sensor 12 for detecting the storage amount of the wastewater stored therein, and an atmosphere opening valve 14.
The drain valve 10 is provided at a position which is the lowermost part of the lower tank 2 when the lower tank 2 is arranged at a predetermined position. The drain valve 10 is connected to an external drain pipe (not shown) for discharging dirty water from the lower tank 2 to the outside. The drain valve 10 is an electrically operated valve that opens and closes based on an electrical signal. In addition, in the following description, the electric valve will be described as one that opens and closes the ball valve by the rotating operation of the motor having an excellent sealing property.

The water level sensor 12 is attached at a predetermined height from the inner bottom of the lower tank 2, and outputs a signal when the dirty water stored inside reaches. The water level sensor 12 is set at a water level detection position so as to output a signal when the sewage stored therein reaches, for example, about 70% of the volume of the lower tank 2. The position where the water level sensor 12 is attached is preferably above the position where the water level sensor 12 detects the water level, for example, in the vicinity of the position where the connecting pipe 6 of the lower tank 2 is connected. In addition, as a mounting form of the water level sensor 12 to the lower tank 2, for example, as shown in FIG. 2A, a cylindrical water level sensor mounting portion 13 that projects from the outer periphery of the lower tank 2 and communicates with the internal space is provided. The water level sensor mounting portion 13 may be provided and mounted.

The atmosphere release valve 14 is attached above the water level sensor 12, and when the valve is opened, it communicates with the internal space of the lower tank 2 and the external space, and by closing the valve, the internal space and the external space of the lower tank 2 are connected. Cut off communication. An electric valve that opens and closes the valve based on an electrical signal is applied to the atmosphere opening valve 14.
The drain valve 10 and the atmosphere release valve 14 described above may be attached directly to the lower tank 2 or via a connecting pipe or the like.

The connecting pipe 6 includes a communication opening/closing valve 16 that opens/closes a connection state between the lower tank 2 and the upper tank 4. An electrically operated valve that opens and closes based on an electrical signal is applied to the communication opening/closing valve 16. The lower tank 2 and the upper tank 4 may be directly connected by the communication opening/closing valve 16 without interposing the connecting pipe 6.

The upper tank 4 is provided above the lower tank 2. The term “upper” does not mean that the upper tank 4 is arranged directly above the lower tank 2 and includes a state in which the upper tank 4 is displaced with respect to the lower tank 2 in the vertical direction. That is, the upper tank 4 and the lower tank 2 are set in a vertical positional relationship. In the present embodiment, the upper tank 4 will be described assuming that the bottom of the upper tank 4 is located higher than the ceiling of the lower tank 2. The upper tank 4 is provided with a pressure reducing on-off valve 18, a pressure sensor 20 for detecting the internal pressure, and a drain pipe connecting portion 4A.

The pressure reducing on-off valve 18 is provided at a position which is the uppermost part of the upper tank 4 when the upper tank 4 is arranged at a predetermined position. A pipe 22 extending from the vacuum pump 8 is connected to the decompression opening/closing valve 18, and the upper tank 4 and the lower tank 2 are decompressed by opening the valve while the vacuum pump 8 is driven. Further, the decompression opening/closing valve 18 closes the valve when the vacuum pump 8 is stopped, and shuts off the path from the vacuum pump 8 to the upper tank 4. This prevents outside air from flowing backward through the vacuum pump 8 and flowing into the upper tank 4 when the vacuum pump 8 is stopped.

The pressure sensor 20 detects the pressure inside the upper tank 4 and outputs a signal when a predetermined pressure is reached. That is, the pressure sensor 20 functions as a pressure switch. The position where the pressure sensor 20 is attached is preferably near the position where the pressure reducing on-off valve 18 of the upper tank 4 is connected. As a mounting form of the pressure sensor 20 to the upper tank 4, for example, as shown in FIG. 2B, a cylindrical pressure sensor mounting portion 21 protruding from the outer periphery of the upper tank 4 and communicating with the internal space is provided. It is preferable to provide the pressure sensor and to mount it via the pressure sensor mounting portion 21.

The drainage pipe connecting portion 4A is provided, for example, so as to be located above the upper tank 4 when the upper tank 4 is arranged at a predetermined position, and extends from, for example, a drainage storage portion (not shown) at the source of wastewater. The drainage pipe 26 is connected. A valve 24 is provided between the drainage storage section and the upper tank 4 to open and close the flow of dirty water from the drainage storage section to the upper tank 4. The valve 24 is provided, for example, in a drainage storage part of a source of sewage and is connected to an operation body such as a switch or a lever provided so as to be operable by a user. Then, the user operates the operating body to open the valve 24, which enables the drainage of the dirty water from the drainage storage section to the upper tank 4 through the drainage pipe 26. When the operation is stopped, the valve 24 is closed to drain the drainage. Outflow of dirty water from the storage portion to the upper tank 4 via the drain pipe 26 is stopped.

Further, the lower tank 2 and the upper tank 4 are connected by a bypass pipe 28 at a position different from the position where the connecting pipe 6 is connected so that their internal spaces can communicate with each other. In the present embodiment, one end side of the bypass pipe 28 is connected to the pressure sensor mounting portion 21 provided in the upper tank 4, and the other end side is connected to the water level sensor mounting portion 13 provided in the lower tank 2. As a preferable position where the upper tank 4 and the bypass pipe 28 are connected to each other, it is assumed that the waste water that is assumed to be stored in the upper tank 4 is discharged from the lower tank 2 until the drain valve 10 is closed. It may be higher than the amount, but considering an unexpected situation, for example, it may be connected in the vicinity of the pressure reducing on-off valve 18, and the pressure sensor provided in the upper tank 4 as in the present embodiment. It is advisable to connect the mounting portion 21 so as to cut into the tank side. Further, the preferable position where the lower tank 2 and the bypass pipe 28 are connected is provided above the liquid level when all the dirty water stored in the upper tank 4 flows into the lower tank 2 via the connecting pipe 6. And good. More preferably, it is preferable to connect the upper tank 4 to the lower tank 2 at a position where it is difficult for the dirty water flowing into the tank to be taken in. For example, as in the present embodiment, the water level sensor mounting portion 13 provided for mounting the water level sensor 12 on the lower tank 2 may be connected so as to interrupt the tank side.

The bypass pipe 28 is provided with a bypass valve 30 that opens and closes the communication between the lower tank 2 and the upper tank 4 via the bypass pipe 28. An electromagnetic valve that opens and closes the valve based on an electrical signal is applied to the bypass valve 30. Here, the electromagnetic valve will be described, for example, by using an electromagnetic actuator such as a solenoid that is superior in responsiveness of opening and closing of the valve as compared with the above-described electrically operated valve.

The vacuum pump 8, the drain valve 10, the water level sensor 12, the communication on-off valve 16, the pressure reducing on-off valve 18, the pressure sensor 20, and the bypass valve 30 are connected to a control panel 32, among which the vacuum pump 8, the drain valve 10, The communication opening/closing valve 16, the pressure reducing opening/closing valve 18, and the bypass valve 30 operate based on a signal output from the control panel 32. That is, the control board 32 individually outputs signals for opening and closing the valves of the drain valve 10, the communication opening/closing valve 16, the pressure reducing opening/closing valve 18, and the bypass valve 30, and also outputs a signal for starting or stopping the driving of the vacuum pump 8. To do.

Hereinafter, the operation of the drainage device 1 according to the present embodiment and the control of the control panel 32 will be described.
[Preparation before driving]
First, the control panel 32 outputs a signal for closing the drain valve 10 and the atmosphere opening valve 14 provided in the lower tank 2 to close the valves. Further, a signal for opening the valve is output to the communication opening/closing valve 16 provided in the connecting pipe 6 that connects the lower tank 2 and the upper tank 4, and the valve is closed to the bypass valve 30 provided in the bypass pipe 28. Output a signal. Further, a signal for opening the valve is output to the pressure reducing on-off valve 18 provided in the upper tank 4. As a result, the internal space of the lower tank 2 and the internal space of the upper tank 4 are integrated and connected to the vacuum pump 8. While maintaining this state, the control panel 32 outputs a signal for driving the vacuum pump 8 to the vacuum pump 8 to operate the vacuum pump 8. By driving the vacuum pump 8, the air in the lower tank 2 and the upper tank 4 is discharged, and the internal pressure is reduced. When the pressure in the lower tank 2 and the upper tank 4 reaches a predetermined pressure, the pressure sensor 20 detects it and outputs it to the control panel 32. The control panel 32 receives a signal from the pressure sensor 20 (a signal notifying that the pressures of the lower tank 2 and the upper tank 4 have reached a predetermined negative pressure state), and outputs a signal to close the pressure reducing on-off valve 18. A signal for stopping the driving of the vacuum pump 8 is output, the pressure reducing on-off valve 18 is closed, and the driving of the vacuum pump 8 is stopped. This completes the pre-operation preparation of the drainage device 1.

[Driving]
Then, when the user operates the operating body and opens the valve 24, the dirty water is sucked from the drainage storage part of the source of the dirty water, flows into the upper tank 4 through the drainage pipe 26, and then from the connecting pipe 6. It flows down to the lower tank 2, and dirty water is stored in the lower tank 2.

The drainage operation from the drainage reservoir is repeated, and a predetermined amount of dirty water is stored in the lower tank 2 as shown by F in the figure as shown in FIG. 3A, and when the water level sensor 12 detects it, the water level is detected. The sensor 12 outputs a signal to the control board 32. The control panel 32 receives a signal from the water level sensor 12 to output a signal to close the communication opening/closing valve 16 to close the communication opening/closing valve 16 and drain the drainage water in order to discharge the dirty water stored in the lower tank 2. A signal for opening the valve is output to the valve 10 and the atmosphere opening valve 14, and the drain valve 10 and the atmosphere opening valve 14 are opened. In the present embodiment, since the motor-operated valve is applied to the communication opening/closing valve 16 and the drain valve 10, it takes a predetermined time from when a signal is input to each of the signal valves 16 and 10 until the valve is completely closed. Therefore, the control panel 32 outputs a signal for closing the communication opening/closing valve 16 to open the drain valve 10 and the atmosphere opening valve 14 after a predetermined time elapses until the communication opening/closing valve 16 is completely closed. Is output.

As a result, the dirty water stored in the lower tank 2 in a state where the lower tank 2 is separated from the upper tank 4 is discharged from the lower tank 2 to the outside. That is, the upper tank 4 can discharge the dirty water in the lower tank 2 while maintaining a predetermined depressurized state.

Since the negative pressure is maintained in the upper tank 4 by closing the communication opening/closing valve 16 in the state where the lower tank 2 is separated, the drainage operation from the drainage reservoir can be continued. Then, while the dirty water stored in the lower tank 2 is discharged, as shown in FIG. 3B, the dirty water discharged from the drainage storage section by repeating the draining operation is changed to the upper tank 4 as shown by F in the figure. Stored in.

Then, after the drainage of the dirty water from the lower tank 2 is completed, the control panel 32 outputs a signal to close the drain valve 10 and the atmosphere release valve 14 to close the drain valve 10 and the atmosphere release valve 14, and to communicate with each other. A signal for opening the valves is output to the opening/closing valve 16 and the bypass valve 30 to open the communication opening/closing valve 16 and the bypass valve 30, and the lower tank 2 is connected to the upper tank 4. Since the drain valve 10, the atmosphere opening valve 14 and the communication opening/closing valve 16 are electric valves as described above, it takes a predetermined time to open and close. Therefore, the control board 32 outputs a signal for closing the drain valve 10 and the atmosphere opening valve 14 to close the drain valve 10 and the atmosphere opening valve 14 after a predetermined time elapses until the drain valve 10 and the atmosphere opening valve 14 are completely closed. A signal for opening the bypass valve 30 is output. As a result, the sewage stored in the upper tank 4 is discharged to the lower tank 2 via the communication opening/closing valve 16, and the air in the lower tank 2 in the atmospheric pressure state is passed to the upper tank 4 in the negative pressure state via the bypass valve 30. Flows in.

The control board 32 outputs a signal for opening the communication opening/closing valve 16 and the bypass valve 30, and outputs a signal for closing the valve to the bypass valve 30 after a lapse of a predetermined time. The time from the output of the open signal to the bypass valve 30 to the output of the close signal is set to, for example, a time shorter than the time when the communication opening/closing valve 16 is completely opened.

Since the communication opening/closing valve 16 is an electric valve and the bypass valve 30 is a solenoid valve, for example, when the control panel 32 outputs a signal to open the communication opening/closing valve 16 and the bypass valve 30 at the same time, the communication opening/closing valve 16 is completely closed. Before opening, the bypass valve 30 is completely opened first. Since there is a time lag between the open states of the valves 16 and 30, the waste water stored in the upper tank 4 starts flowing down to the lower tank 2 through the communication opening/closing valve 16, and at the same time, the lower tank 2 Air flows into the upper tank 4 via the bypass valve 30, and the pressures of the lower tank 2 and the upper tank 4 can be made constant before the communication opening/closing valve 16 is completely opened. As a result, the air in the lower tank 2 under atmospheric pressure is prevented from flowing into the upper tank 4 via the communication opening/closing valve 16 and the discharge of sewage from the upper tank 4 to the lower tank 2 is smoothly carried out. be able to. That is, the connection pipe 6 provided with the communication opening/closing valve 16 functions as a sewage discharge path for discharging sewage to the lower tank 2, and the bypass pipe 28 provided with the bypass valve 30 removes the air in the lower tank 2. It functions as an air inflow path for flowing into the upper tank 4. Therefore, the bypass valve 30 has only to be opened until the pressures of the lower tank 2 and the upper tank 4 become constant, and therefore, as described above, the bypass valve 30 may be opened for a short time.

As a result, the lower tank 2 in the atmospheric pressure state is decompressed by the negative pressure of the upper tank 4 and becomes ready to suck the dirty water again. Further, even while the lower tank 2 is discharging the dirty water, the upper tank 4 can suck the dirty water and store it in the upper tank 4, so that the drainage device 1 can be continuously operated.
During the above operation, the vacuum pump 8 is driven according to the internal pressure state of the upper tank 4 detected by the pressure sensor 20 or the internal pressure state when the upper tank 4 and the lower tank 2 are integrated. Is repeatedly started or stopped. Further, the opening/closing operation of the pressure reducing on/off valve 18 is also controlled according to the start and stop of the driving of the vacuum pump 8, and when the vacuum pump 8 is driven, the pressure reducing on/off valve 18 is opened and the vacuum pump 8 stops driving. The pressure reducing on-off valve 18 is closed when performing.

In addition, the control panel 32 outputs a signal for closing the valve to the communication opening/closing valve 16 and then outputs a signal for opening the valve to the drain valve 10 and the atmosphere opening valve 14, and to the drain valve 10 and the atmosphere opening valve 14. The time difference from the output of the signal for closing the valve to the output of the signal for opening the valve to the communication opening/closing valve 16 and the bypass valve 30 is executed by, for example, timer control.

As described above, according to the drainage device 1 according to the present embodiment, the upper tank 4 and the lower tank 2 are connected via the communication opening/closing valve 16 and the communication opening/closing valve 16 is opened, whereby the upper tank Since the 4 and the lower tank 2 can be integrated, a stable negative pressure is maintained. That is, a stable suction force can be secured.

Further, by closing the communication on-off valve 16, the upper tank 4 and the lower tank 2 are separated, and even while the dirty water in the lower tank 2 is being discharged, the suction of the dirty water can be continued due to the negative pressure of the upper tank 4. , Continuous operation (drainage) is possible.

When the discharge of the dirty water of the lower tank 2 is completed, the upper tank 4 and the lower tank 2 are connected to each other, and the negative pressure state of the upper tank 4 is temporarily changed until the negative pressure of the set pressure is reached. The pressure is increased (decreased) and the suction force is reduced, but the negative pressure of the upper tank 4 is maintained, and the air volume (volume) of the lower tank 2 is smaller than that of the upper tank 4. Thus, the set pressure can be restored in a short time, so that the stop time of the drainage operation can be shortened even when the drainage operation from the drainage storage unit needs to be stopped, for example.

Further, when the dirty water in the lower tank 2 was discharged, the atmosphere opening valve 14 was opened to allow the outside air (air) to flow in and generate a large inflow noise of air. Since the air is discharged, the amount of negative pressure air in the lower tank 2 is small and the inflow speed of the air into the lower tank 2 is slowed down. Therefore, the inflow sound of the air can be reduced and the generation of noise can be suppressed.

After discharging the dirty water from the lower tank 2, the communication opening/closing valve 16 is opened to integrate the upper tank 4 and the lower tank 2, and the air at the atmospheric pressure of the lower tank 2 flows into the upper tank 4. By opening the bypass valve 30 together with 16, it is possible to allow the air in the lower tank 2 to flow mainly from the lower tank 2 into the upper tank 4 via the bypass valve 30. As a result, the upper tank 4 and the lower tank 2 instantly have the same pressure, so that the sewage collected in the upper tank 4 flows smoothly from the upper tank 4 to the lower tank 2, and the upper tank 4 moves to the lower tank 2. Vibration when sewage moves can be reduced.
Therefore, in order to obtain the above-mentioned effect more reliably, the bypass pipe 28 is connected to the lower tank 2 and the upper tank 4 so that only air flows through the bypass pipe 28 that connects the lower tank 2 and the upper tank 4. Preferably the position is set. The bypass pipe 28 may be omitted depending on the pipe diameter of the connecting pipe 6 and the like.

As described above, according to the drainage device 1 according to the present embodiment, if there is at least one vacuum pump 8, continuous operation is possible, it is inexpensive, control is simple, economical and maintenance is easy. Become.

In the above embodiment, each of the lower tank 2 and the upper tank 4 is provided, but the number is not limited to this, and the number may be changed appropriately. In terms of cost, by increasing the number of each of the lower tank 2 and the upper tank 4 to one, an increase in cost can be suppressed. However, for example, depending on the shape of the space at the installation location, there may be two lower tanks 2, or It is assumed that the installation of the upper tank 4 will be facilitated and the maintainability after installation will be improved by using two upper tanks 4. In such a case, the number of lower tanks 2 and upper tanks 4 may be changed appropriately.

Although not shown, in addition to the lower tank 2 and the upper tank 4, a third tank may be provided between the valve 24 and the upper tank 4. That is, the third tank is connected to the drain pipe 26 shown in FIG. 1 via a pipe. By providing the third tank in this way, it is possible to reduce pressure fluctuations in the lower tank 2 and the upper tank 4 when drainage is discharged from the drainage storage section. That is, the third tank functions as a shock absorber (buffer) that reduces pressure fluctuations in the lower tank 2 and the upper tank 4. Since the third tank only needs to be connected to the drainage pipe 26, it has a large degree of freedom in the place where it is placed, and while effectively utilizing the space when actually installing the drainage device 1, the drainage device 1 Driving can be made more stable. It is needless to say that when the third tank is used, it may be connected to the drain pipe 26 so as not to suck the drainage flowing through the drain pipe 26.

Further, in the above-described embodiment, the lowermost part of the upper tank 4 is described as being arranged at a position higher than the uppermost part of the lower tank 2. However, in the upper tank 4, the lowermost part of the upper tank 4 is provided in the lower tank 2. It may be provided so as to be located above the sensor 12.

Further, the types of valves applied to the drain valve 10, the atmosphere opening valve 14, the communication opening/closing valve 16, the decompression opening/closing valve 18, the bypass valve 30 and the like, for example, selection of an electric valve or a solenoid valve may be appropriately changed.

1 drainage device, 2 lower tank, 4 upper tank, 4A drain pipe connection,
6 connection pipe, 8 vacuum pump, 10 drainage valve, 12 water level sensor, 14 atmosphere release valve,
16 communication opening/closing valve, 18 pressure reducing opening/closing valve, 20 pressure sensor, 22 piping,
26 drainage pipes, 28 bypass pipes, 30 bypass valves, 32 control panels.

Claims (2)

A drainage device for draining a liquid stored in a drainage storage unit using negative pressure,
Lower tank,
An upper tank that is provided above the lower tank and that is openably and closably connected to the internal space of the lower tank via an opening/closing valve,
A vacuum pump connected to the upper tank,
The upper tank is
A pressure switch for controlling the drive of the vacuum pump,
A drainage pipe connecting portion to which a pipe extending from the drainage storing portion is connected,
The lower tank is
A water level sensor that detects the water level of the wastewater stored in the internal space,
A drain valve for discharging the drainage stored in the internal space,
An atmosphere release valve that allows the internal space to communicate with the external space,
A drainage device comprising: The drainage device according to claim 1, wherein the volume of the upper tank is larger than the volume of the lower tank.

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