JP2023116980A - Drain pit and draining method - Google Patents

Abstract

To provide a drain pit capable of automatically discharging accumulated water further reliably.SOLUTION: A drain pit 1 has an electrode type water level gauge 40 that detects a water level based on the energization state of an electrode that contacts water and energizes, a float type water level gauge 41 that detects a water level based on the movement of a float accompanying the water level of a liquid surface, and a drainage section 3 that can drain water to the outside. The operation of the drainage section 3 is controlled based on at least one of a detection signal of the electrode type water level gauge 40 and a detection signal of the float type water level gauge 41.SELECTED DRAWING: Figure 2

Description

The present invention relates to drainage pits and drainage methods.

Conventionally, there has been known a technique for automatically draining water by detecting the level of water that accumulates in a pit. For example, in Patent Document 1, a pit drain tank having a level sensor is provided in the pit at the bottom of the elevator hoistway that drains water from the air conditioner provided in the elevator car, and the drain pump is started and operated based on the output signal of the sensor. An automatic draining device is described which stops and automatically drains the tank.

JP-A-5-105350

By the way, in the drainage pit that collects and drains rainwater from the site, electrode-type water level gauges are used instead of float-type water level gauges, which can become undetectable due to floating objects caught in the drainage. . However, when a large amount of pure water is poured into the site during fire extinguishing training, etc., water with low conductivity flows into the drainage pit, and there is a risk that the electrode-type water level gauge will not be able to detect the water level.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a drain pit capable of automatically draining accumulated water more reliably.

(1) The drainage pit according to the present invention includes an electrode-type water level gauge that detects the water level based on the energized state of electrodes that are in contact with the liquid and that detects the water level based on the movement of the float that accompanies the level of the liquid surface. and a drainage device capable of draining liquid to the outside. controls the behavior of

(2) The water level detection position of the electrode type water level gauge is positioned below the water level detection position of the float type water level gauge.

(3) In the drainage pit according to the present invention, the electrode-type water level gauge can detect a first lower water level and a first upper water level set at a position higher than the first lower water level, and the float The type water level gauge can detect a second lower limit water level and a second upper limit water level set at a position higher than the second lower limit water level, and detects the first upper limit water level or the second upper limit water level. The drainage device is operated when the water level is low, and the operation of the drainage device is stopped when the first lower limit water level or the second lower limit water level is detected.

(4) In the drainage pit according to the present invention, a groove is formed in the bottom, and the electrode type water level gauge, the float type water level gauge, and the drainage device are provided in the groove.

ADVANTAGE OF THE INVENTION According to this invention, the drainage pit which can discharge the accumulated water more reliably automatically can be provided.

1 is a schematic diagram showing an example of a drainage system provided on a power plant site according to an embodiment of the present invention; FIG. FIG. 3 is a cross-sectional view around a water level detection unit according to one embodiment of the present invention; It is a schematic diagram for explaining an example of a water level detection unit according to one embodiment of the present invention. 4 is a flowchart for explaining an example of the flow of waste water treatment according to one embodiment of the present invention;

An example of a drainage system S provided within the site of a power plant according to an embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. FIG. 1 is a schematic diagram showing an example of a drainage system S provided on a power plant site G according to one embodiment of the present invention. FIG. 2 is a sectional view around the water level detector 4 according to one embodiment of the present invention. The drainage system S includes, for example, a transformer installation 2 provided at the power plant site G and a drainage pit 1 provided adjacent to the transformer installation 2 .

The drainage pit 1 is a structure formed of concrete in a concave shape on the site G of the power plant. In the example of FIG. 1, the drain pit 1 is provided adjacent to the transformer installation 2 . Note that the location where the drainage pit 1 is formed is not limited to this.

The drainage pit 1, as shown in FIG. A water level detection unit 4, a drainage unit 3 for draining water in the drainage pit 1 based on the detection result of the water level detection unit 4, a terminal block for connection with the water level detection unit 4, and a circuit for water level control. A control circuit 50 is provided which includes:

Next, the water level detector 4 will be described with reference to FIGS. FIG. 3 is a schematic diagram for explaining an example of the water level detector 4 according to one embodiment of the present invention. The water level detector 4 has an electrode type water level gauge 40 and a float type water level gauge 41 .

The electrode-type water level gauge 40 is a water level gauge that detects the water level based on the energization state of two or more electrodes in contact with a conductive liquid. In this embodiment, as shown in FIG. 3, the electrode-type water level gauge 40 has four electrodes: a common electrode 401, an L1 water level detection electrode 402, an H1 water level detection electrode 403, and an HH water level detection electrode 404. and a base 400 to which one end is fixed.

A common electrode 401 is a common ground electrode connected to the other three electrodes, and the length of the common electrode 401 is set to be the longest among the four electrodes. The lengths of the other three electrodes are set shorter in the order of the L1 water level detection electrode 402, the H1 water level detection electrode 403, and the HH water level detection electrode 404. Therefore, the lower ends of the four electrodes are located above the common electrode 401, the L1 water level detection electrode 402, the H1 water level detection electrode 403, and the HH water level detection electrode 404 in this order as shown in FIG. The electrode-type water level gauge 40 detects the water level based on the energization state of the electrodes when the common electrode 401 and at least one other electrode come into contact with water as liquid.

In addition, the number of electrodes of the electrode type water level gauge 40 is not limited to the above example, and may be three or five or more. Moreover, the number of ground electrodes that the electrode-type water level gauge 40 has may be plural instead of one. Further, the electrode-type water level gauge 40 is provided substantially on the bottom surface of the water level detection section installation groove 10 so as to protrude upward from the water level detection section installation groove 10 .

The electrode type water level gauge 40, as shown in FIG. detectable. Specifically, in the electrode-type water level gauge 40, the first lower limit water level L1 is detected when the common electrode 401 and the L1 water level detection electrode 402 come into contact with water. Further, in the electrode-type water level gauge 40, the first upper limit water level H1 is detected when the common electrode 401 and the H1 water level detection electrode 403 come into contact with water. Moreover, in the electrode type water level gauge 40, the HH water level shown in FIGS. In addition, in this embodiment, the HH water level detection electrode 404 is used for full water alarm.

The float-type water level gauge 41 is a water gauge that has a float that moves up and down and detects the water level based on the movement of the float accompanying the water level of the liquid surface. In this embodiment, as shown in FIG. 3, the float-type water level gauge 41 includes a microswitch 410 that switches between ON and OFF by a predetermined force, a rod 411 connected to a shaft (not shown) in the microswitch 410, It has a float 412 through which a rod 411 is slidable, and upper and lower stops 413 and 414 which are fixable on the shaft.

In the float-type water gauge 41, when the water level rises, the float 412 rises due to buoyancy, and the float 412 comes into contact with the upper limit stopper 413, and the buoyancy is transmitted to lift the rod 411 and the shaft. Microswitch 410 is turned on when an upward force greater than a predetermined amount acts on microswitch 410 from rod 411 and shaft. In this embodiment, the position of the upper limit stopper 413 is set at the second upper limit water level H2.

Further, when the water level drops from the second upper limit water level H2, the float 412 is separated from the upper limit stopper 413, and the upward force from the float 412 to the rod 411 and shaft ceases to act. On the other hand, the microswitch 410 is maintained in the ON state because a downward force greater than the predetermined force does not act on the microswitch 410 .

Further, when the float 412 descends and reaches the lower limit stopper 414 as the water level drops, force is transmitted to the shaft and the rod 411 by the mass of the float 412 . Microswitch 410 is turned off when a downward force greater than or equal to a predetermined amount acts on microswitch 410 from rod 411 and shaft. In this embodiment, the position of the lower limit stopper 414 is set at the second lower limit water level L2.

Thus, the float-type water level gauge 41 turns on the microswitch 410 when the water level rises to the second upper limit water level H2, and when the water level drops from the second upper limit water level H2 to the second lower limit water level L2, The ON state is maintained, and when the water level drops below the second lower limit water level L2, the microswitch 410 is turned OFF. The float-type water level gauge 41 is provided above the water level detection section installation groove 10 so as to protrude upward from the water level detection section installation groove 10 .

The float type water level gauge 41 is set above the second lower limit water level L2 which is set above the first upper limit water level H1 of the electrode type water level gauge 40 and the second lower limit water level L2 as shown in FIG. A second upper limit water level H2 can be detected. In other words, the water level detection position of the electrode type water level gauge 40 is located below the water level detection position of the float type water level gauge 41 .

The drainage pit 1 according to this embodiment controls the operation of the drainage section 3 based on at least one of the detection signal of the electrode type water level gauge 40 and the detection signal of the float type water level gauge 41 . Details will be described later.

Next, the drainage section 3 as a drainage device will be described. The drainage part 3 can drain the liquid to the outside. For example, the drainage section 3 has a drainage pump 30 for sucking water in the drainage pit 1 and a drainage pipe 31 for flowing the water sucked from the drainage pump 30 to an external drainage ditch. Moreover, in this embodiment, the drainage pump 30 performs a predetermined operation by the control circuit 50 based on the detection signal of the water level detection section 4 . Also, the drainage pump 30 is provided on the bottom surface of the water level detection unit installation groove 10 .

Next, the control circuit 50 will be explained. The control circuit 50 includes a known self-holding circuit using a terminal block 500 for connection with the water level detection unit 4 as shown in FIGS. It includes a circuit for water level control such as The terminal block 500 is provided with a terminal 501, a terminal 502, a terminal 503, and a terminal 504, and a wiring between the electrode type water level gauge 40 of the water level detection unit 4 and the float type water level gauge 41. wiring is connected.

For example, the terminal 501 is connected to one of two wirings of the electrode type water level gauge 40 and the common electrode 401 and the float type water level gauge 41 . Also, the terminal 502 is connected to the wiring between the L1 water level detection electrode 402 of the electrode type water level gauge 40 . Further, the terminal 503 is connected to the wiring between the H1 water level detection electrode 403 of the electrode type water level gauge 40 and the remaining wiring of the two wirings of the float type water level gauge 41 .

In the control circuit 50 according to the present embodiment, for example, the terminal 502 is connected to the wiring on the negative electrode side of the power source of the switch of the relay in the self-holding circuit. Further, the terminal 503 is connected to the negative wire of the power supply in the wiring of the coil of the relay in the self-holding circuit and the negative wire of the power supply in the wiring of the circuit for outputting to the drainage pump 30 .

For example, when the terminal 503 is energized, the relay switch is turned on, and the output to the drainage pump 30 is performed to start the drainage pump 30 . In addition, in the control circuit 50, if the terminal 503 is energized while the terminal 502 is energized, the terminal 502 and the relay switch in the ON state are maintained while the terminal 502 is energized even if the terminal 503 is not energized. The ON state of the relay switch is maintained by energizing the coil of the relay.

Further, the circuit for outputting to the drainage pump 30 continues to be energized through the terminal 502 and the relay switch in the ON state, and the operation of the drainage pump 30 also continues. In addition, when the terminal 502 is no longer energized, the relay coil is no longer energized via the terminal 502 and the relay switch in the ON state, so the relay switch is turned OFF and the output to the drainage pump 30 is stopped. The circuit is no longer energized, and the drainage pump 30 stops operating.

Next, water level control in the drainage pit 1 using the drainage pump 30 will be described with reference to FIG. FIG. 4 is a flow chart for explaining an example of the flow of wastewater treatment according to one embodiment of the present invention, which relates to one embodiment of the present invention when the water level lower than the first lower limit water level L1 rises. Water level control in drainage pit 1 is shown.

First, the water level in the drainage pit 1 rises to the first upper limit water level H1, and the H1 water level detection electrode 403 of the electrode type water level gauge 40 comes into contact with water. At this time, if the water accumulated in the drainage pit 1 is conductive water, the common electrode 401 and the H1 water level detection electrode 403 are energized (step S10: YES), and the drainage pump 30 is started (step S11). .

The water in the drainage pit 1 is drained by the operation of the drainage pump 30, and the water level is lowered. Even if the water level in the drainage pit 1 falls below the first upper limit water level H1, since the common electrode 401 and the L1 water level detection electrode 402 are energized, the drainage pump 30 is kept activated. Next, when the water level in the drainage pit 1 falls below the first lower limit water level L1 (step S12: YES), the activated state of the drainage pump 30 is canceled and the drainage pump 30 stops (step S13).

On the other hand, if the water accumulated in the drainage pit 1 is pure water or other low-conductivity water, no current will flow between the common electrode 401 and the H1 water level detection electrode 403 (step S10: NO). In this case, the water level continues to rise, and the raised water comes into contact with the float 412 of the float type water level gauge 41 . The float 412 rises due to the buoyancy of the rising water and contacts the upper limit stopper 413 . When the buoyancy applied to the float 412 applied to the upper limit stopper 413 exceeds a predetermined force, the rod 411 and shaft are lifted, turning on the microswitch 410 (step S14) and starting the drain pump 30 (step S15).

The water in the drainage pit 1 is discharged by operating the drainage pump 30, and the water level is lowered. Since no downward force exceeding the predetermined force is applied to the rod 411 and the shaft, the ON state of the microswitch 410 is maintained.

Next, when the water level in the drainage pit 1 reaches the second lower limit water level L2, the float 412 which has descended as the water level drops and the lower limit stopper 414 come into contact with each other. When the water level further drops, the force of the mass of the float 412 applied to the lower limit stopper 414 becomes equal to or greater than a predetermined force, and the shaft and rod 411 are lowered to release the ON state of the microswitch 410 (step S16: YES). The drainage pump 30 stops (step S17).

The drainage pit 1 configured as described above includes an electrode-type water level gauge 40 that detects the water level based on the energized state of the electrodes that are in contact with the liquid and the movement of the float that accompanies the water level of the liquid. A float type water level gauge 41 for detecting the water level by means of a float type water level gauge 41 and a drainage section 3 capable of draining liquid to the outside, and at least one of the detection signal of the electrode type water level gauge 40 and the detection signal of the float type water level gauge 41 Based on this, the operation of the drainage unit 3 is controlled.

As a result, even when the water accumulated in the drainage pit 1 is pure water and the electrode type water level gauge 40 cannot detect the water level, the float type water level gauge 41 can detect the water level. Based on the detection signal of the type water level gauge 41, the drainage unit 3 can be activated to perform drainage treatment. On the other hand, in the drainage pit 1, the electrode-type water level gauge 40 can detect the water level even when the water accumulated in the drainage pit 1 adheres to the float-type water level gauge 41 and the detection performance deteriorates. Therefore, the drainage unit 3 can be activated based on the detection signal of the electrode type water level gauge 40 to perform the drainage treatment. Therefore, the drainage pit 1 according to the present invention can more reliably and automatically drain the accumulated water.

Further, the water level detection position of the electrode type water level gauge 40 is located below the water level detection position of the float type water level gauge 41 .

Thus, in the drainage pit 1 according to the present invention, when water accumulates in the drainage pit 1, the electrode-type water level gauge 40 comes into contact with the water earlier than the float-type water level gauge 41 does. If the accumulated water contains impurities that will stain the float type water level gauge 41, the drainage pit 1 detects the water with the electrode type water level gauge 40, and the detection signal of the electrode type water level gauge 40 is detected. Since the drainage unit 3 is activated based on the above to perform drainage treatment, it is possible to suppress the adhesion of dirt or the like to the float type water level gauge 41 .

Further, the electrode type water level gauge 40 can detect a first lower limit water level L1 and a first upper limit water level H1, and the float type water level gauge 41 can detect a second lower limit water level L2, a second upper limit water level H2, can be detected, the drainage unit 3 is operated when the first upper limit water level H1 or the second upper limit water level H2 is detected, and the drainage unit 3 is operated when the first lower limit water level L1 or the second lower limit water level L2 is detected to stop

As a result, the control circuit 50 of the drainage pit 1 can start and stop the drainage section 3 based on the detection signal of the electrode type water level gauge 40 or the detection signal of the float type water level gauge 41. Wastewater treatment can be controlled.

A water level detector installation groove 10 is formed in the bottom, and an electrode type water level gauge 40 , a float type water level gauge 41 , and a drainage section 3 are provided in the water level detection section installation groove 10 .

As a result, devices such as the drainage pump 30 of the drainage section 3 can be accommodated below the bottom of the drainage pit 1, and the space in the drainage pit 1 can be utilized more effectively.

[Modification]
It should be noted that the present invention is not limited to the above-described embodiments, and includes modifications, improvements, and the like within the scope of achieving the object of the present invention. For example, the arrangement of the water level detection unit 4 and the drainage unit 3 described above is an example, and is not limited to these.

For example, in the drainage pit 1 according to the present invention, after detecting the water level of the first upper limit water level H1, the pump is stopped when the water level of the first lower limit water level L1 is detected. The pump may be stopped when the water level of 1 upper limit water level H1 is detected. Further, after detecting the water level of the second upper limit water level H2, the pump may be stopped when the water level of the first lower limit water level L1 is detected.

Further, in the present embodiment, hardware such as the control circuit 50 controls the operation of the drainage pump 30 based on the detection signal of the water level detection unit 4, but the present invention is not limited to this, and hardware having other configurations may be made to perform the operation. Alternatively, it may be executed by software implemented by a processor that executes arithmetic processing. Processors that perform arithmetic processing are, for example, single processors, multiprocessors, and multicore processors. Array) and other processing circuits.

When a series of processes is to be executed by software, a program constituting the software is installed in a computer or the like from a network or a recording medium. The computer may be a computer built into dedicated hardware. The computer may also be a computer capable of executing various functions by installing various programs, such as a general-purpose personal computer.

A recording medium containing such a program is not only constituted by a removable medium that is distributed separately from the main body of the device in order to provide the program to the user, but is also provided to the user in a state pre-installed in the main body of the device. It consists of a recording medium, etc. Removable media are composed of, for example, magnetic disks (including floppy disks), optical disks, or magneto-optical disks. Optical discs are composed of, for example, CD-ROMs (Compact Disc-Read Only Memory), DVDs (Digital Versatile Discs), Blu-ray (registered trademark) Discs, and the like. The magneto-optical disk is composed of an MD (Mini-Disc) or the like. Further, the recording medium provided to the user in a state of being pre-installed in the apparatus body is composed of, for example, a ROM in which programs are recorded, a hard disk, or the like.

1 drainage pit 3 drainage part 40 electrode type water level gauge 41 float type water level gauge 50 control circuit

Claims (5)

an electrode-type water level gauge that detects the water level based on the energized state of electrodes that are energized in contact with the liquid;
a float-type water level gauge that detects the water level based on the movement of the float accompanying the water level of the liquid surface;
a drainage device capable of draining liquid to the outside;
with
A drainage pit for controlling the operation of the drainage device based on at least one of a detection signal of the electrode type water level gauge and a detection signal of the float type water level gauge. The detection position of the water level of the electrode type water level gauge is
2. The drainage pit according to claim 1, which is located below the water level detection position of the float type water gauge. The electrode-type water level gauge is capable of detecting a first lower limit water level and a first upper limit water level set at a position higher than the first lower limit water level,
The float type water level gauge is capable of detecting a second lower limit water level and a second upper limit water level set at a position higher than the second lower limit water level,
The drainage device is operated when the first upper limit water level or the second upper limit water level is detected, and the operation of the drainage device is stopped when the first lower limit water level or the second lower limit water level is detected. Or the drainage pit according to 2. A groove is formed in the bottom,
4. The drainage pit according to any one of claims 1 to 3, wherein the electrode type water level gauge, the float type water level gauge, and the drainage device are provided in the groove. A drainage method performed in a drainage pit, comprising:
Detection signal of the electrode type water level gauge that detects the water level based on the energized state of the electrode that contacts the liquid and detection of the float type water level gauge that detects the water level based on the movement of the float accompanying the water level of the liquid. A method of draining, including a control step for controlling operation of a drainage device capable of draining liquid to the outside based on at least one of the signals.

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