JPH1115533A - Water level controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the failure that is caused by the idle operation of an underwater pump when the normal water level control becomes impossible due to the abnormality of a water level sensor, etc. SOLUTION: When a water level sensor 12 detects that the level of a sewage tank 20 reaches an operation level in a prescribed range, a motor 11a of an underwater pump 11 is driven in the the tank 20 and the waste water is discharged out of the tank 20. At the same time, a timer starts to count the time and the drive of the motor 11a is stopped after it's driven for a fixed time. Thus, the drive of the motor 11a is stopped even when the sewage level is lowered less than a prescribed range due to the abnormality of the sensor 12. As a result, the failure of the motor 11a can be prevented. When a level upper limit sensor 13 detects that the sewage level exceeds its prescribed upper limit value in the tank 20, the motor 11a is driven for a prescribed time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water level control device for controlling the level of sewage in a sewage tank within a predetermined range by a submersible pump disposed at the bottom of the sewage tank.

[0002]

2. Description of the Related Art Sewage in a sewage tank for temporarily storing sewage discharged from each household is usually controlled by a water level control device.
It is controlled to be within a predetermined range,
It prevents sewage from overflowing the sewage tank. The water level control device provided in the sewage tank has a submersible pump installed at the bottom of the sewage tank and a water level sensor for detecting the level of sewage in the sewage tank.

[0003] The water level sensor is turned on when the sewage reaches the operating water level which is the upper limit of the standard control water level,
Thereby, the submersible pump is operated, and the sewage in the sewage tank is discharged. Then, when the water level of the sewage reaches the stop water level, which is the lower limit of the preset standard control water level, the water level sensor is turned off, whereby the operation of the submersible pump is stopped, and the sewage in the sewage tank is discharged. Is done.

[0004] Japanese Patent Application Laid-Open No. 6-57811 discloses that
Water level control that provides a bubble type water level sensor that detects the water level based on the gas pressure fluctuation when gas is supplied into the sewage and generates bubbles, and controls the submersible pump based on the detection result of this water level sensor An apparatus is disclosed. In the water level control device disclosed in this publication, a float type water level upper limit sensor for detecting that the sewage in the sewage tank has reached an upper limit position just before overflowing is provided, and the sewage water level is set to an upper limit by the water level upper limit sensor. When the position is detected, the submersible pump is driven for a predetermined time. With such a configuration, even when the sewage is at a predetermined operation water level, even when the submersible pump is not operating properly due to an abnormality in the water level sensor, the sewage water level reaches the upper limit position. When the water level upper limit sensor operates, the submersible pump is driven for a predetermined time, so that overflow of the sewage from the sewage tank is reliably prevented.

[0005]

However, in such a water level control device, when the sewage in the sewage tank is discharged by driving the submersible pump, the sewage is kept at a predetermined level due to an abnormality in the water level sensor or the like. If the drive of the submersible pump is not stopped and the drive of the submersible pump is continued despite the stop water level, the submersible pump will continue to be driven in an idling state in which the sewage cannot be sucked up. As described above, when the submersible pump is idlely operated, the temperature of the motor of the submersible pump becomes high, and the motor may be broken.

The present invention has been made to solve such a problem.
It is an object of the present invention to provide a water level control device that can reliably prevent the submersible pump from running idle and failing when the water level in the sewage tank cannot be controlled normally by the submersible pump.

[0007]

According to the water level control device of the present invention, a water pump disposed in a sewage tank and a water level of the sewage in the sewage tank are controlled so as to discharge sewage in the sewage tank. A water level sensor for detecting that the water level is within the water level, a water level upper limit sensor for detecting that the level of the sewage in the sewage tank has reached a predetermined upper limit position, and a sewage tank based on the detection result of the water level sensor. A control unit that controls the submersible pump so as to maintain the water level of the sewage within a predetermined range, and drives the submersible pump for a predetermined time based on the detection result of the water level upper limit sensor, When the submersible pump is driven based on the detection result of the water level sensor, the control unit detects that the submersible pump has been driven for a predetermined time and stops driving the submersible pump. And wherein it is in the jar.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing an example of an embodiment of a water level control device according to the present invention. This water level control device includes a submersible pump 11 installed at the bottom of a sewage tank 20 into which sewage flows and stored, a bubble type water level sensor 12 installed at the bottom of the sewage tank 20, and a sewage tank 20. A float type upper limit water level sensor 13 for detecting the upper limit water level by floating on the surface of the stored sewage.

The submersible pump 11 installed at the bottom of the sewage tank 20 has a motor 11a arranged at an upper part and a pump casing 11b arranged below the motor 11a. , Motor 1
An impeller (not shown) that is driven to rotate by 1a is provided. When the impeller is rotated by the motor 11a, sewage in the sewage tank 20 is sucked into the pump casing 11b, and is discharged into a discharge pipe 11c provided perpendicular to the pump casing 11b. Discharge pipe 1
The sewage discharged into 1b is discharged to the outside of the sewage tank 20 through the discharge pipe 11b.

A bubble type water level sensor 12 installed at the bottom of the sewage tank 20 discharges bubbles into the sewage in the sewage tank 20 by a pump, and based on the pressure of the bubbles, the sewage tank 20.
The level of sewage in the building is detected. The water level sensor 12 is turned on when the sewage in the sewage tank 20 reaches the upper limit operation water level in a predetermined range set in advance, and the pressure of bubbles discharged into the sewage increases. Then, the water level of the sewage falls to a stop water level on the lower limit side of the predetermined range, and the pressure of bubbles discharged into the sewage decreases, thereby turning off the water.

The float type water level upper limit sensor 13 is configured such that the sewage flowing into the sewage tank 20 is used for the bubble type water level sensor 1.
When the sewage is at an upper limit position immediately before overflowing from the sewage tank 20 at a higher water level than the upper limit water level at which the sewage 2 is turned on, the sewage floats on the sewage surface to be turned on.

The motor 11a of the submersible pump 11 is controlled by a control unit 14 provided above the sewage tank 20. The control unit 14 includes an output of the water level sensor 12 and a water level upper limit sensor 13 Output is given.

FIG. 2 is a control circuit diagram in the control unit 14 provided above the sewage tank 20. The motor 11 a of the submersible pump 11 is provided with a three-phase AC power supply,
And the normally open contact 32a of the electromagnetic relay. The AC power supply is connected to a control changeover switch 33 that is operated when the level of the sewage in the sewage tank 20 is switched between automatic control and manual control. The control changeover switch 33 has a manual side normally open contact 33a and an automatic side normally closed contact 33b connected in parallel, and the manual side normally open contact 33a is connected to the excitation coil 32 of the electromagnetic relay.
Are connected in series. When the exciting coil 32 is excited, the normally open contact 32a provided between the AC power supply and the motor 11a of the submersible pump 11 is turned on.

A timer 44 is connected to the normally closed contact 33b on the automatic side of the control changeover switch 33.
A parallel circuit of the normally open contacts 34a and 35a of the pair of electromagnetic relays is connected to the timer 44. The normally open contacts 32a for controlling the driving of the motor 11a are connected to the parallel circuit of the normally open contacts 34a and 35a.
Are connected.

A parallel circuit of a normally open contact 37a turned on by a timer 37 and a normally open contact 46a turned on by an exciting coil 46 of an electromagnetic relay is connected to the AC power supply. The normally closed contact 38b operated by the exciting coil 38 of the electromagnetic relay and the alarm lamp 39 are connected to a series circuit, and the normally open alarm cancel switch 4 for canceling the lighting of the alarm lamp 39.
1 and a normally open contact 38 operated by an exciting coil 38
a and a series circuit of the exciting coil 38 of the electromagnetic relay.

The voltage of the AC power supply is transformed by a transformer 42, and the normally open contact 12a of the bubble type water level sensor 12 is changed.
, A normally closed contact 46b of the timer 46, and the exciting coil 34 of the electromagnetic relay. further,
The voltage of the AC power source transformed by the transformer 42 is supplied to a pump 12p for generating bubbles in the sewage in the bubble type water level sensor 12, and this pump 1p
By driving the 2p, air bubbles are generated in the sewage tank 20.

The voltage transformed by the transformer 42 is supplied to a series circuit of a normally open contact 35c operated by an exciting coil 35 of an electromagnetic relay and a timer 37, and a water level upper limit sensor 13 and a reset normally closed. It is provided to a series circuit of a contact 37b and an exciting coil 35 of an electromagnetic relay. The connection point between the normally open contact 35c operated by the exciting coil 35 and the timer 37 is also connected to the connection point between the water level upper limit sensor 13 and the normally closed contact 37b for resetting.

Further, the transformed voltage by the transformer 42 is:
A parallel circuit of the normally open contact 44a of the timer 44, the normally open contact 45a of the exciting coil 45 of the electromagnetic relay, the normally closed contact 35b of the exciting coil 35, and the exciting coil 45 of the electromagnetic relay
And a parallel circuit of the normally open contact 45c of the exciting coil 45 and the normally open contact 45c of the exciting coil 46 of the electromagnetic relay, and the exciting coil 46 of the electromagnetic relay.
Is also given to the series circuit.

The operation of the water level control device having such a configuration is as follows. The water level control device is normally in an automatic control state in which the normally-closed contact 33b on the automatic side of the control changeover switch 33 is turned on.
When the sewage flows into the chamber 0 and the sewage reaches the upper limit operation water level of a preset predetermined range, the bubble type water level sensor 12
Is turned on. Thereby, the exciting coil 34 of the electromagnetic relay is excited, the normally closed contact 33b of the control changeover switch 33 and the normally open contact 34a connected in series with the series circuit of the timer 44 are turned on, and the exciting coil 32 is excited. . When the exciting coil 32 is excited, the normally open contact 32 provided between the AC power supply and the motor 11a of the submersible pump 11 is provided.
is turned on, and the motor 11a is driven.

When the motor 11a of the submersible pump 11 is driven, the sewage in the sewage tank 20 is discharged to the outside of the sewage tank 20 through the discharge pipe 11c, and the level of the sewage in the sewage tank 20 decreases. Then, when the water level of the sewage becomes equal to or lower than the stop water level on the lower side of the predetermined range, the normally open contact 12a of the bubble type water level sensor 12 is turned off, the excitation coil 34 is demagnetized, and the normally open contact 34a is turned off. As a result, the excitation coil 32 is demagnetized, the normally open contact between the AC power supply and the motor 11a is turned off, the motor 11a of the submersible pump 11 is stopped, and the discharge of the sewage from the sewage tank 20 is completed. I do.

As described above, the motor 11 a of the submersible pump 11 is controlled based on the water level of the sewage in the sewage tank 20, so that the sewage in the sewage tank 20 does not overflow from the sewage tank 20, It is controlled within a predetermined range.

In such water level control, if an abnormality occurs in the bubble type water level sensor 12, the submersible pump 1
1 is driven, even though the sewage is discharged from the sewage tank 20, even if the water level of the sewage in the sewage tank 20 becomes equal to or lower than the stop water level on the lower limit side of a predetermined range set in advance. The normally open contact 12a of the water level sensor 12 may not be turned off. In this case, the normally open contact 12a of the water level sensor 12 continues to be on.
The excitation coil 32 is not demagnetized, so that the submersible pump 11
, The discharge of the sewage from the sewage tank 20 is continued without stopping the driving of the motor 11a.

However, when the normally open contact 12a of the water level sensor 12 is turned on in order to drive the motor 11a of the submersible pump 11, the exciting coil 34 is excited and the normally open contact 34a is turned on. When a predetermined time preset in the timer 44 elapses, the normally open contact 4 of the timer 44 is started.
4a is turned on. As a result, the electromagnetic relay 45 is excited, the two normally open contacts 45a and 45c are turned on, the excitation coil 45 is self-held, and the excitation coil 46 of the electromagnetic relay is excited to
Two normally open contacts 46a and 46c are turned on. When the normally open contacts 46a and 46c are turned on, the electromagnetic relay 46 is self-held and the alarm lamp 39 is turned on. Further, at the same time, one normally closed contact 46b is turned off. Further, at the same time when the exciting coil 46 is excited, the normally closed contact 46b is turned off, and the electromagnetic relay 3
4 is demagnetized, and the normally open contact 35a is turned off. Thereby, the electromagnetic relay 32 is demagnetized, the normally open contact 32a is turned off, and the driving of the motor 11a is stopped.

As described above, even if an abnormality occurs in the bubble type water level sensor 12, after the predetermined time set by the timer 44 elapses, the driving of the motor 11a is stopped even if the motor 11a is driven. Therefore, the motor 11a does not become hot due to the inability of the submersible pump 11 to suck up the sewage in the sewage tank 20, so that the failure of the motor 11a can be prevented. In addition, the alarm lamp 39 is turned on simultaneously with the stop of the drive motor 11a, so that it is possible to easily recognize that an abnormality has occurred in the bubble type water level sensor 12.

Further, in such water level control, even if an abnormality occurs in the bubble type water level sensor 12 and the sewage in the sewage tank 20 becomes higher than the operating water level on the upper limit side in a predetermined range, the water level sensor 12 is constantly operated. When the open contact 12a does not turn on, the sewage in the sewage tank 20 reaches the upper limit water level immediately before overflow, so that the water level upper limit sensor 13 turns on. As a result, the exciting coil 35 is excited, and the timer 37 is operated to start timing. When the exciting coil 35 is excited, the normally open contact 35c is turned on to be in a self-holding state, and the normally open contact 35a is turned on, the exciting coil 32 is excited, and the normally open contact 32a is turned on. And the motor 11a is driven. Thereby, the sewage tank 20
The sewage in the inside is discharged, and there is no possibility that the sewage overflows from the sewage tank 20.

Thereafter, when a predetermined time set by the timer 37 elapses, the normally closed contact 37b of the timer 37 is turned off. Thereby, the exciting coil 35
Is demagnetized, the normally open contact 35c turns off, and the exciting coil 35
Is released, and the timer 37 is reset. At the same time, the normally open contact 35a is turned off, the exciting coil 32 is demagnetized, and the normally open contact 32a is turned off, so that the drive of the motor 11a is stopped. At the same time, the normally open contact 37a is turned on, and the alarm lamp 39
Is turned on to notify that the bubble type water level sensor 12 is abnormal.

When the alarm release switch 41 is turned on when the alarm lamp 39 is informed that an abnormality has occurred in the bubble type water level sensor 12, the excitation coil 38 is excited. This exciting coil 3
8, the normally open contact 38a for self-holding is turned on, and the normally closed contact 38b is turned off, so that the alarm lamp 39 is turned off.

In the above embodiment, the water level sensor 12
Is a bubble type that detects the water level based on the water pressure of the sewage in the sewage tank 20. However, the present invention is not limited to such a configuration. For example, an ultrasonic wave is transmitted from above the sewage water surface toward the water surface. Alternatively, an ultrasonic type water level sensor that detects a water level based on ultrasonic waves reflected on the water surface, a pressure type water level sensor that operates by detecting the water pressure of sewage, or the like may be used.

[0030]

As described above, the water level control device of the present invention
When the submersible pump is driven for a predetermined time while controlling the submersible pump based on the water level sensor to maintain the water level of the sewage within a predetermined range, the driving of the submersible pump is stopped. In addition, even if an abnormality occurs in the water level sensor, there is no possibility that the motor of the submersible pump becomes hot and breaks down, and the submersible pump can be stably used for a long period of time.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an example of an embodiment of a water level control device of the present invention.

FIG. 2 is a circuit diagram showing an example of a control circuit used in the water level control device.

[Explanation of symbols]

 11 Submersible pump 11a Motor 11b Pump casing 12 Water level sensor 13 Water level upper limit sensor 20 Sewage tank

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[Procedure amendment]

[Submission date] June 30, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0003

[Correction method] Change

[Correction contents]

[0003] The water level sensor is turned on when the sewage reaches the operating water level which is the upper limit of the standard control water level,
Thereby, the submersible pump is operated, and the sewage in the sewage tank is discharged. Then, when the water level of the sewage reaches the stop water level which is the lower limit of the preset standard control water level, the water level sensor is turned off, thereby stopping the driving of the submersible pump .

Claims (2)

[Claims] Claims: 1. To discharge sewage in a sewage tank,
A submersible pump located in the sewage tank, a water level sensor that detects that the level of sewage in the sewage tank is within a predetermined range, and that the water level of the sewage in the sewage tank has reached a predetermined upper limit position Based on the detection result of the water level sensor, based on the detection result of the water level sensor, while controlling the submersible pump to maintain the water level of the sewage in the sewage tank within a predetermined range, the detection result of the water level upper limit sensor A control unit adapted to drive the submersible pump for a predetermined time based on the detection result of the water level sensor, when the submersible pump is driven for a predetermined time. A water level control device wherein the drive of a submersible pump is stopped upon detecting that it is being driven. 2. The water level control device according to claim 1, wherein the water level upper limit sensor is of a float type floating on the water surface.