JP2017180373A - Water level controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress frequency of error processing for a detection error of a pressure sensor, in a case where the inside of a water storage tank temporarily becomes negative pressure.SOLUTION: A bubble type liquid gauge 30 has a pressure sensor 34 configured to detect pressure in a water storage tank 15, and a water level in the water storage tank 15 is detected based on the detection result of the pressure sensor 34. An error determination unit 36 is configured to determine that there is a detection error in a case where the pressure sensor 34 detects negative pressure. A controller 35, after activating a submerged pump 20, performs control so as not to execute at least part of error processing for detection error of the pressure sensor 34 until a predetermined setting time elapses.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a water level control device.

  Conventionally, a submersible pump is installed in a sewage tank that temporarily stores sewage discharged from each household. And when the amount of sewage increases, sewage is pumped up with a submersible pump, discharged to a downstream sewer pipe or the like, and sewage distribution processing is promoted (see, for example, Patent Document 1). .

  The water level control device of Patent Document 1 includes a pressure sensor that detects the air pressure supplied into the sewage through the air pump. If the sewage flows into the sewage tank and rises to a predetermined level, the air pressure that matches the water level. As a result, the controller determines that the water level has risen to a predetermined water level, and drives the submersible pump to discharge the sewage. And if a water level falls to the predetermined pump stop water level by discharge | emission of dirty water, a pressure sensor will detect the air pressure corresponding to a predetermined pump stop water level, and the drive of a submersible pump will be stopped.

JP 2001-193140 A

  However, for example, when a conventional water level control device is applied to a highly airtight sewage tank, the pressure sensor detects negative pressure (pressure lower than atmospheric pressure) that should not be detected in normal operation. There is a risk that an error process such as an emergency stop of the pump or an abnormality notification will occur if it is detected and judged to be abnormal.

  Specifically, in a highly airtight sewage tank, sewage is discharged, while air corresponding to the volume of the discharged sewage does not flow from the outside, so that the inside of the sewage tank may become negative pressure. At this time, if the detection part of the pressure sensor is exposed to the air or is near the water surface, the pressure sensor may detect a negative pressure. In this type of device, when the pressure sensor detects negative pressure, it is judged as a detection error and an error message such as sending an error message or stopping the pump is performed. Due to frequent processing, the operator's response work has become a burden.

  The present invention has been made in view of such points, and an object thereof is to suppress frequent occurrence of handling work associated with error processing when the inside of the water tank temporarily becomes negative pressure. .

A first invention is a pump installed in a water storage tank in which water is stored, and discharges water from the water storage tank;
A water level detector that detects a pressure in the water tank, and detects a water level of the water tank based on a detection result of the pressure sensor;
The pump is started when the water level detected by the water level detection unit during a stop of the pump is equal to or higher than a predetermined startup water level, while the water level detected by the water level detection unit during operation of the pump is A control unit that stops the pump when it becomes below a predetermined stop water level lower than the start water level;
An error determination unit that determines a detection error when negative pressure is detected by the pressure sensor;
The control unit performs control so that at least a part of error processing due to a detection error of the pressure sensor is not performed until a predetermined set time elapses after the pump is started. It is.

  In the first invention, when a negative pressure is detected by the pressure sensor, the error determination unit determines that a detection error has occurred and performs error processing. Until error elapses, at least part of error processing is not performed.

  Thereby, even when the inside of a highly airtight water tank becomes a negative pressure temporarily, it can suppress that an unnecessary error process occurs frequently and can perform water level control continuously.

  Specifically, in highly airtight water storage tanks, the inside of the water storage tank temporarily becomes negative pressure due to the insufficient volume of air from the outside with respect to the volume of drained sewage. The detection part of the pressure sensor in a shallow position may detect negative pressure. In other words, even if the pressure sensor detects a negative pressure, it does not always cause a malfunction such as a disconnection in the pressure sensor or a negative pressure over a long period of time, affecting the pump operation control. It is not desirable to send a message or stop the pump.

  Therefore, in the present invention, it is unnecessary to perform error processing due to a pressure sensor detection error in a state where a predetermined elapsed time has elapsed since the pump was started and the water tank is likely to have returned to atmospheric pressure. To prevent frequent error handling.

  In addition, it is conceivable that the record of the detection error is accumulated in the memory while the pump is not stopped or the notification operation is not performed.

According to a second invention, in the first invention,
The control unit controls the pump to continue operation until the set time elapses.

  In 2nd invention, even if the inside of a water tank becomes a negative pressure during setting time, a driving | operation of a pump can be continued, without forcedly stopping a pump by the error process by a detection error.

According to a third invention, in the first or second invention,
When it is determined that the error determination unit is a detection error, a notification unit that performs a predetermined notification operation as error processing,
The notification unit is configured not to perform the notification operation until the set time elapses.

  In the third invention, until the set time elapses, the detection error is not determined, or the notification operation is not performed even if the detection error is determined. Thereby, it can suppress that alerting | reporting operation | occurrence | occurrence | occurring frequently based on the unnecessary detection error which does not have influence on water level control.

A fourth invention is a pump installed in a water storage tank in which water is stored, and discharges water from the water storage tank;
A water level detector that detects a pressure in the water tank, and detects a water level of the water tank based on a detection result of the pressure sensor;
The pump is started when the water level detected by the water level detection unit during a stop of the pump is equal to or higher than a predetermined startup water level, while the water level detected by the water level detection unit during operation of the pump is A control unit that stops the pump when it becomes below a predetermined stop water level lower than the start water level;
An error determination unit that determines a detection error when negative pressure is detected by the pressure sensor;
The control unit controls to continue the operation of the pump until a predetermined extended time elapses after the water level in the water tank becomes equal to or lower than the stop water level, while error processing due to a detection error. It is characterized by controlling so that at least one part of this may not be performed.

  In the fourth invention, after the water level in the water tank becomes equal to or lower than the stop water level, the operation of the pump can be continued and the water in the water tank can be reliably discharged until a predetermined extended time elapses. I am doing so. During this extended time, at least a part of the error processing is not performed even if the detection unit of the pressure sensor detects a negative pressure.

  Here, in order to detect the water level with the pressure sensor, it is assumed that there is a change in air pressure depending on the water level, that is, the pressure sensor is in water. That is, the pressure sensor is still in water when the water level is at the stop water level. When the pressure inside the water tank becomes negative, the pressure sensor in the water detects a pressure lower than the pressure corresponding to the actual water level, so the pressure sensor detects the stop water level in the air or in relatively shallow water. There is a high probability of detecting negative pressure during the extended period of time.

  Therefore, in the present invention, it is unnecessary to prevent at least a part of the error processing based on the detection error during the extended time during which the pressure sensor is likely to detect the negative pressure, so that the water level control is not affected. To prevent frequent error handling.

  Further, if the apparatus originally has a timer function for counting the extension time, it is not necessary to separately provide a timer function for measuring a set time for not detecting a detection error, and the timer function can be shared.

  According to the present invention, even when the inside of a highly airtight water tank temporarily becomes negative pressure, it is possible to prevent unnecessary error processing from occurring frequently and to continue water level control.

It is a side view which shows schematic structure of the water level control apparatus which concerns on this embodiment. It is a timing chart figure which shows the timing which performs error processing. It is a timing chart figure which shows the timing which performs an error process in the water level control apparatus which concerns on this Embodiment 2. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature and is not intended to limit the present invention, its application, or its use.

Embodiment 1
As shown in FIG. 1, the water level control device 10 controls the water level of a water tank 15 such as a manhole in which water is stored. The water storage tank 15 is provided with an inflow pipe 16 and an outflow pipe 17, and water appropriately flows into the water storage tank 15 through the inflow pipe 16.

  A submersible pump 20 is installed inside the water storage tank 15 to pump up and discharge the water. The suction bell mouth 21 of the submersible pump 20 is disposed in a recess 18 provided at the bottom of the water storage tank 15. The discharge pipe 22 of the submersible pump 20 is connected to the outflow pipe 17 of the water storage tank 15 so that the water pumped up by the submersible pump 20 is discharged to the outside of the water storage tank 15. The operation and stop of the submersible pump 20 are controlled by a controller 35 as a control unit that executes water level control described later.

  The water level in the water tank 15 is detected by a bubble-type liquid level gauge 30 as a water level detection unit. The bubble-type liquid level gauge 30 includes an air pump 31, an air discharge part 32 arranged so as to be immersed in water, an air tube 33 connecting the air pump 31 and the air discharge part 32, And a pressure sensor 34 for detecting air pressure.

  When the bubble type liquid level gauge 30 supplies air into the water in the water storage tank 15 to generate bubbles, the air pressure in the air tube 33 is detected by the pressure sensor 34, and the water level is detected based on the detection result. Is configured to detect. The pressure sensor 34 is connected to the controller 35, and the detection value of the pressure sensor 34 is transmitted to the controller 35.

  The controller 35 controls the operation of the submersible pump 20 based on the water level detected by the bubble type liquid level gauge 30. Specifically, the controller 35 activates the submersible pump 20 when the water level detected by the bubble-type liquid level gauge 30 becomes equal to or higher than a predetermined activation water level H1 while the submersible pump 20 is stopped. Thereby, the water in the water tank 15 is discharged outside, and the water level of the water tank 15 is lowered.

  On the other hand, the submersible pump 20 is stopped when the water level detected by the bubble-type liquid level gauge 30 during the operation of the submersible pump 20 falls below a predetermined stop water level L. Thereby, the pumping up of the water is finished, and the water flowing in from the outside is stored in the water storage tank 15.

  In the present embodiment, the submersible pump 20 is not immediately stopped when the stop water level L or lower, but after the predetermined extension time has elapsed after the stop water level L or lower. The operation of the pump 20 is continued. Thereby, the water stored in the recess 18 of the water storage tank 15 can be reliably discharged.

  The controller 35 includes an error determination unit 36 that determines a detection error when a negative pressure is detected by the pressure sensor 34. The controller 35 is connected to a notification unit 37 that performs a predetermined notification operation.

  The notification unit 37 includes, for example, a monitor and displays an error message indicating a detection error of the pressure sensor 34. The notification unit 37 is not limited to a monitor, and may be a notification buzzer, a notification lamp, or the like. That is, the notification operation of the notification unit 37 notifies the operator of a detection error, for example, displaying an error message on a monitor at hand or a remote monitor, sounding a notification buzzer, or blinking a notification lamp. Anything to do.

  By the way, in the highly airtight water storage tank 15, sewage is discharged, while the air corresponding to the volume of the discharged sewage does not flow from the outside, so that the inside of the water storage tank 15 temporarily becomes negative pressure. is there. At this time, the pressure sensor 34 in the water tank 15 may detect a negative pressure. In this case, the error determination unit 36 determines that it is a detection error, and the controller 35 performs control such as displaying an error message on the notification unit 37 or forcibly stopping the submersible pump 20. That is, detection errors frequently occur even though the disconnection or the like does not occur in the pressure sensor 34.

  Therefore, in the present embodiment, it is possible to suppress the frequent occurrence of unnecessary detection errors that do not affect the water level control and to continuously perform the water level control. Hereinafter, description will be made with reference to the timing chart of FIG.

  First, at time T1, the water level in the water storage tank 15 becomes the activation water level H1, and the controller 35 activates the submersible pump 20 and starts discharging water. At this time, positive pressure is detected by the pressure sensor 34. Then, the controller 35 performs control so that at least a part of error processing due to a detection error is not performed until a predetermined set time elapses.

  The set time can be appropriately set by an operator inputting from the controller 35 in accordance with the structure of the water storage tank 15, the performance of the submersible pump 20, and the like. For example, it can be set in an arbitrary range such as 1 to 99 seconds in 1 second increments.

  At time T2, the water level in the water storage tank 15 becomes the stop water level L, and the controller 35 continues the operation of the submersible pump 20 until a predetermined extension time elapses.

  At time T3, the negative pressure in the water storage tank 15 is detected by the pressure sensor 34 due to a drop in water pressure due to a drop in water level or a drop in air pressure in the air during the extended time. Here, since the negative pressure is detected by the pressure sensor 34, the submersible pump 20 is forcibly stopped as an error process during the extension time. However, since the predetermined set time has not elapsed at the time T3, the controller 35 controls the notification unit 37 not to perform the notification operation as error processing.

  At time T4, a predetermined extension time has elapsed, but since the submersible pump 20 has already stopped, no particular processing is performed.

  Further, since air gradually flows into the water storage tank 15 and a predetermined set time has elapsed at time T5, if the pressure sensor 34 detects negative pressure, error processing based on a negative pressure error is performed. However, at time T5, the pressure sensor 34 detects a positive pressure, and no detection error occurs.

  At time T6, the atmospheric pressure in the water tank 15 is positive.

  Thus, in the water level control apparatus 10 according to the present embodiment, when a negative pressure is detected by the pressure sensor 34, the error determination unit 36 determines that there is a detection error, but the submersible pump 20 The notification operation of the error processing is not performed until a predetermined elapsed time has elapsed since the activation of.

  Thereby, even when the inside of the highly airtight water storage tank 15 temporarily becomes a negative pressure, it is possible to suppress the frequent occurrence of unnecessary error notification and to continue the water level control.

<< Embodiment 2 >>
FIG. 3 is a timing chart showing the timing for performing error determination in the water level control apparatus according to the second embodiment. Hereinafter, the same portions as those in the first embodiment are denoted by the same reference numerals, and only differences will be described.

  As shown in FIG. 3, first, at time T1, the water level in the water storage tank 15 becomes the activation water level H1, and the controller 35 activates the submersible pump 20 and starts discharging water. At this time, the air discharge part 32 is immersed in water, and the pressure sensor 34 detects a positive pressure. Then, the controller 35 performs control so that error processing due to a detection error is not performed until a predetermined set time elapses.

  At time T2, the water level in the water storage tank 15 becomes the stop water level L, and the controller 35 continues the operation of the submersible pump 20 until a predetermined extension time elapses. At this time, the pressure in the water storage tank 15 is a negative pressure, but the pressure sensor 34 detects a positive pressure.

  At time T3, since the inflow of air with respect to the discharge amount of sewage is small during the extended time, the pressure in the water storage tank 15 further decreases and the detection pressure decreases due to the decrease in the water level, and the negative pressure is detected by the pressure sensor 34. The However, since the predetermined set time has not elapsed at time T3, the error process based on the negative pressure error is not performed, and the controller 35 continues the operation of the submersible pump 20 and notifies the notification unit 37. Control not to perform the notification operation.

  At time T4, since the predetermined extension time has elapsed, the controller 35 stops the operation of the submersible pump 20.

  At time T5, the water level in the water storage tank 15 increases and air gradually flows into the water storage tank 15, and the pressure sensor 34 detects a positive pressure.

  Since a predetermined set time has elapsed at time T6, the error determination unit 36 determines a detection error. At time T6, the air discharge part 32 is immersed in water, the positive pressure is detected by the pressure sensor 34, and no detection error occurs.

  At time T7, the atmospheric pressure in the water storage tank 15 is also positive.

  In this way, even if the negative pressure is detected by the pressure sensor 34 during the set time and the negative pressure is detected by the pressure sensor 34, no error processing is performed. Further, the operation can be continued without forcibly stopping the submersible pump 20.

<< Other Embodiments >>
About the said embodiment, it is good also as following structures.

  In the present embodiment, the atmospheric pressure in the water tank 15 remains negative during the extended time. For example, if the water tank 15 is not so airtight, the water pressure in the water tank 15 is increased during the extended time. May return from negative pressure to positive pressure.

  For such a water tank 15, the controller 35 continues the operation of the submersible pump 20 until a predetermined extension time elapses after the water level in the water tank 15 becomes equal to or lower than the stop water level L. On the other hand, the error determination unit 36 may be controlled not to perform at least a part of error processing due to a detection error of the pressure sensor 34.

  That is, at least a part of the error processing due to the detection error is not performed only during the extended time when the air discharge unit 32 is exposed to the air or near the water surface and the pressure sensor 34 is likely to detect the negative pressure. By doing so, it is possible to suppress frequent occurrence of unnecessary error processing that does not affect water level control. On the other hand, when there is a high possibility of a detection error due to other disconnection or the like, error processing such as pump stop or error notification can be performed promptly.

  As described above, the present invention has a highly practical effect that can suppress frequent occurrence of error processing due to a detection error of the pressure sensor when the inside of the water tank temporarily becomes negative pressure. Since it is obtained, it is extremely useful and has high industrial applicability.

10 Water Level Control Device 15 Water Tank 20 Submersible Pump (Pump)
30 Bubble level gauge (water level detector)
34 Pressure sensor 35 Controller (control unit)
36 Error determination unit 37 Notification unit

Claims (4)

A pump installed in a water reservoir in which water is stored, and discharging the water in the water reservoir;
A water level detector that detects a pressure in the water tank, and detects a water level of the water tank based on a detection result of the pressure sensor;
The pump is started when the water level detected by the water level detection unit during a stop of the pump is equal to or higher than a predetermined startup water level, while the water level detected by the water level detection unit during operation of the pump is A control unit that stops the pump when it becomes below a predetermined stop water level lower than the start water level;
An error determination unit that determines a detection error when negative pressure is detected by the pressure sensor;
The control unit performs control so that at least a part of error processing due to a detection error of the pressure sensor is not performed until a predetermined set time elapses after the pump is started. Control device. In claim 1,
The said control part is controlled so that the driving | operation of the said pump is continued until the said setting time passes, The water level control apparatus characterized by the above-mentioned. In claim 1 or 2,
When it is determined that the error determination unit is a detection error, a notification unit that performs a predetermined notification operation as error processing,
The notification unit is configured to not perform the notification operation until the set time elapses. A pump installed in a water reservoir in which water is stored, and discharging the water in the water reservoir;
A water level detector that detects a pressure in the water tank, and detects a water level of the water tank based on a detection result of the pressure sensor;
The pump is started when the water level detected by the water level detection unit during a stop of the pump is equal to or higher than a predetermined startup water level, while the water level detected by the water level detection unit during operation of the pump is A control unit that stops the pump when it becomes below a predetermined stop water level lower than the start water level;
An error determination unit that determines a detection error when negative pressure is detected by the pressure sensor;
The control unit controls to continue the operation of the pump until a predetermined extended time elapses after the water level in the water tank becomes equal to or lower than the stop water level, while error processing due to a detection error. A water level control device that performs control so that at least a part of the control is not performed.

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