JP2019105215A - Vertical shaft pump and precedent standby operation method therefor - Google Patents

Abstract

To provide a vertical shaft pump in which a clutch can be engaged and disengaged upon precedent standby operation without requiring water level detection means such as a water level meter, and a precedent standby operation method for the vertical shaft pump.SOLUTION: The vertical shaft pump comprises: a prime mover 9; a pump shaft 4; an impeller 6; a clutch 5 interposed between the prime mover and the pump shaft and transmitting/interrupting the rotational power of the prime mover to the pump shaft; a rotation detector 11 detecting the rotational speed of the pump shaft; and a control device 12. The pump shaft can rotate together with the prime mover 9 due to the rotational power of the prime mover transmitted through the viscous lubricating oil interposed between the clutch plates of the clutch while the prime mover is driven and the clutch is disengaged. The control device engages the clutch when the rotational speed decreases to the predetermined lower limit while the motor is driven and the clutch is disengaged, and the control device disengages the clutch when the rotational speed increases to the predetermined upper limit while the prime mover is driven and the clutch is engaged.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vertical axis pump having a clutch mechanism between a prime mover and a pump shaft, and a method of advance standby operation thereof.

  The vertical pump installed in the pump drainage station is designed to drain water quickly when a large amount of water rapidly flows into the suction water tank. In the preliminary standby operation, when sudden water discharge due to heavy rain or the like is expected, full-speed operation (air operation) of the vertical pump is started from the state of low water level in the suction water tank, depending on the water level of the suction water tank Operation, air-water mixing operation and pumping operation are repeated. Therefore, there is a problem that vibration and noise are easily generated. In addition, special bearings may be used, as the submersible bearing may be damaged during temperature operation due to the temperature rise and wear of the bearing sliding parts, and the submersible bearing may be damaged due to the vibration of the pump during airlock operation. It was necessary to adopt.

In order to solve the problem of such a stand-up vertical shaft pump for standby, for example, a vertical shaft pump provided with a clutch mechanism as described in Patent Document 1 and Patent Document 2 has been proposed.
In this vertical pump, a clutch mechanism is provided between the prime mover driving the vertical pump and the pump shaft, and water level detection means for detecting the water level in the suction water tank is provided, and the water level detection signal from the water level detection means When the water level is reached, only the prime mover is operated with the clutch disconnected and the rotation of the pump shaft is stopped. When the water level rises and reaches a predetermined level, the clutch is connected to operate the vertical pump I am in control. According to this vertical pump, since the airborne operation of the vertical pump at low water level can be avoided, the damage due to the underwater bearing and the vibration due to the airlock operation can be prevented.

JP-A-9-264287 Japanese Patent Application Laid-Open No. 2000-27788

The following problems remain in the above-mentioned prior art.
In the vertical pump provided with the conventional clutch mechanism, in the leading standby operation, the suction water tank is provided with water level detection means such as a water level gauge to detect the water level of the suction water tank, and the air operation and air water are detected according to the detected water level. Operation control is performed so that mixing operation and pumping operation are performed. However, in the water level gauge, the waste in the water tank may be caught in the float and cause the malfunction of the float, may cause malfunction due to the wave of the water surface, or may cause the conduction failure due to corrosion or dirt of the electrode rod. It was not always reliable for water level detection in the water tank.

  The present invention has been made in view of the above-mentioned conventional problems, and it is not necessary to provide a water level detection means such as a water level gauge, and a vertical shaft pump capable of connecting and disconnecting a clutch in advance standby operation and its advance standby operation method. Intended to be provided.

  The present invention adopts the following configuration in order to solve the problems. That is, the vertical shaft pump according to the first aspect of the present invention includes a motor, a pump shaft that is rotationally driven by the motor, an impeller provided at a lower portion of the pump shaft, and an intermediate portion between the motor and the pump shaft. A clutch for transmitting and disconnecting the rotational power of the prime mover to and from the pump shaft, a rotation detector for detecting the rotational speed of the pump shaft, and a control device for controlling the prime mover and the clutch. In a state where the motor is driven and the clutch is disconnected, the pump shaft is driven by the rotational power of the motor transmitted through the viscous lubricating oil interposed between the clutch plates of the clutch. It is possible to rotate, and in a state in which the control device is driving the motor and in a state in which the clutch is disconnected, the rotational speed detected by the rotation detector is a predetermined value. The clutch is connected when the limit value is reduced, and the rotational speed detected by the rotation detector increases to a predetermined upper limit value in a state where the motor is driven and the clutch is connected. At the same time, the clutch is disconnected.

In this vertical pump, the control device connects the clutch when the rotational speed detected by the rotation detector decreases to a predetermined lower limit value while the motor is being driven and the clutch is disconnected, and the motor is Since the clutch is disconnected when the rotational speed detected by the rotation detector rises to a predetermined upper limit in a driven state and in a state in which the clutch is connected, the change in water level in the suction water tank is determined by the rotational speed of the pump shaft This makes it possible to automatically detect the connection and disconnection of the clutch in the pre-waiting operation without providing a water level detection means such as a water level gauge.
That is, in the vertical shaft pump of the present invention, a clutch is interposed between the prime mover and the pump shaft, and in the state where the prime mover is driven and the clutch is disengaged, a change in rotational speed due to rotation of the pump shaft is detected. A clutch is connected, and in a state in which the vertical pump is operated with the clutch connected, a change in rotational speed of the pump shaft is detected to disconnect the clutch. Therefore, a change in the water level of the suction water tank can be reliably detected by a change in the rotational speed of the pump shaft, and it is not necessary to provide a water level detection means such as a water level gauge in the suction water tank. Therefore, operation control of the water level detection means does not disturb operation control due to malfunction such as malfunction or conduction failure, and it is possible to reliably detect a change in rotational speed accompanying a change in water level and to perform a leading standby operation. .
Also, the lower limit value and the upper limit value of the rotational speed of the pump shaft are set in advance, and when the detected value of the rotational speed of the pump shaft falls below the lower limit value, the clutch is connected, and when the detected value exceeds the upper limit value, the clutch Therefore, by appropriately setting the lower limit value and the upper limit value according to the specifications and installation conditions of the vertical shaft pump, it is possible to reliably control the connection and disconnection of the clutch, and it is preferable to be preferred. Standby operation is possible.

  The vertical pump according to a second aspect of the present invention is characterized in that, in the first aspect, the prime mover is an electric motor.

  The vertical shaft pump according to the third invention is characterized in that, in the first invention, the prime mover is an internal combustion engine.

  According to a fourth aspect of the present invention, in the method of leading standby operation of a vertical shaft pump, the vertical shaft pump includes a prime mover, a pump shaft that is rotationally driven by the prime mover, an impeller provided below the pump shaft, and the prime mover The pump shaft includes a clutch interposed between the pump shaft and for transmitting and blocking the rotational power of the prime mover to and from the pump shaft, and a rotation detector for detecting the rotational speed of the pump shaft, the pump shaft comprising: In the state where the motor is driven and the clutch is disconnected, the motor can be rotated by the rotational power of the motor transmitted through a viscous lubricating oil interposed between the motor and the clutch, In a state where a motor is driven and the clutch is disconnected, the clutch is connected when the rotational speed detected by the rotation detector decreases to a predetermined lower limit value, While the prime mover is connected state and the clutch is driven, characterized in that the rotational speed detected by the rotation detector to cut the clutch when increased to a predetermined upper limit value.

According to the present invention, the following effects are achieved.
That is, according to the vertical shaft pump of the present invention and the preceding standby operation method, when the rotational speed detected by the rotation detector decreases to a predetermined lower limit value in a state where the motor is driven and the clutch is disconnected. The clutch is connected to the motor, the motor is driven and the clutch is connected, and the clutch is disconnected when the rotational speed detected by the rotation detector rises to a predetermined upper limit value. It is possible to detect the change of the rotational speed of the pump shaft by the change of the rotational speed of the pump shaft, and to automatically perform the connection and disconnection of the clutch in the preceding standby operation without providing a water level detection means such as a water level gauge.
Therefore, in the present invention, operation control due to malfunction of the water level detection means, malfunction, conduction failure and the like does not affect the operation control, and the change of the rotational speed accompanying the water level change is reliably detected to perform the leading standby operation. It can be carried out.

It is a longitudinal cross-sectional view which shows 1st Embodiment of the vertical axis pump which concerns on this invention. In 1st Embodiment, it is a graph which shows the relationship between the water level of a suction water tank, and the rotational speed of a pump shaft. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the vertical axis pump which concerns on this invention.

  Hereinafter, a first embodiment of a vertical pump according to the present invention will be described based on FIGS. 1 and 2.

  As shown in FIG. 1, the vertical shaft pump 1 in this embodiment includes a motor 9, a pump shaft 4 rotationally driven by the motor 9, an impeller 6 provided below the pump shaft 4, a motor 9 and a pump A clutch 5 interposed between the shaft 4 and the clutch 5 for transmitting and blocking the rotational power of the prime mover 9 to and from the pump shaft 4, a rotation detector 11 for detecting the rotational speed of the pump shaft 4, a prime mover 9 and a clutch 5 And a control device 12 for performing control.

The pump shaft 4 is driven by the rotational power of the prime mover 9 transmitted via the lubricating oil having a viscosity interposed between the clutch plates of the clutch 5 when the prime mover 9 is driven and the clutch 5 is disconnected. It is possible to take along.
The control device 12 connects the clutch 5 when the rotational speed detected by the rotation detector 11 decreases to a predetermined lower limit value with the motor 9 being driven and the clutch 5 disconnected. 9 has a function of disconnecting the clutch 5 when the rotational speed detected by the rotation detector 11 rises to a predetermined upper limit value in a state in which the clutch 9 is driven and the clutch 5 is connected.

The prime mover 9 is an electric motor. The prime mover 9 of the present embodiment is a vertical motor.
The clutch 5 is a hydraulic clutch.
The clutch is connected to the hydraulic pressure supply device 13.
The hydraulic pressure supply device 13 is composed of a hydraulic pump, a solenoid valve, and the like.
As the rotation detector 11, a photoelectric rotation detector is employed.
The control device 12 is configured by an arithmetic processing circuit or the like that performs the above-described function.
The control device 12 is connected to the rotation detector 11, the hydraulic pressure supply device 13 and the motor 9.

  The vertical pump 1 of the present embodiment is suspended in the suction water tank 2, and the upper end of the pump shaft 4 penetrating the outer wall of the discharge elbow 3 is connected to the output side of the hydraulic clutch 5. An impeller 6 is disposed at the lower end of the pump shaft 4, and a bell mouth 8 opened downward is connected to the lower end of the pump casing 7.

  The output shaft 10 of the prime mover 9 disposed at the upper portion is connected to the input side of the clutch 5 through a shaft coupling, and the rotational power of the output shaft 10 of the prime mover 9 is transmitted to the pump shaft 4 through the clutch 5 Is configured as. That is, the rotational power of the output shaft 10 is transmitted to the pump shaft 4 by connecting the clutch 5, and the transmission of the rotational power from the output shaft 10 to the pump shaft 4 is interrupted by disconnecting the clutch 5.

In the vicinity of the upper end portion of the pump shaft 4, a rotation detector 11 for detecting the rotational speed of the pump shaft 4 and transmitting a detection signal is disposed. The detected detection signal is transmitted from the rotation detector 11 to the control device 12.
The control device 12 receives the detection signal from the rotation detector 11, performs a comparison operation between the detected rotational speed and a preset upper limit value and lower limit value, and based on the calculation result, the hydraulic pressure supply device 13 Is configured to control the connection and disconnection of the clutch 5.

Next, a method of leading standby operation by the vertical shaft pump 1 of the present embodiment will be described with reference to FIGS. 1 and 2.
The preceding standby operation method of the present embodiment will be described in the order of (1) to (11) in FIG.

(1) Since water discharge is predicted, the prime mover 9 is started with the clutch 5 disconnected, and standby operation is started. At this time, the water level of the suction water tank 2 is at the lower end level WL1 of the bell mouth 8. In the state where the clutch 5 is disconnected, the power of the prime mover 9 is transmitted to the pump shaft 4 due to the viscosity of the lubricating oil present between the clutch plates, and the pump shaft 4 rotates at a constant speed by corotation.

(2) Water starts to flow into the suction water tank 2, and the water level starts to rise.
(3) When the water level rises to the lower end level WL2 of the impeller 6, it starts to act as a resistance to the rotational torque of the impeller 6, and the resistance gradually increases as the water level rises, and the rotation speed of the impeller 6 gradually decreases.
(4) When the rotational speed of the impeller 6 reaches a preset lower limit (for example, the rotational speed of the pump shaft 4 when the entire impeller 6 is submerged (corresponding to the water level WL3)) A control signal is transmitted to the supply device 13, the clutch 5 is connected, the rotational power of the output shaft 10 is transmitted to the pump shaft 4, and the pumping operation is started.

(5) Then, when the pumping operation is continued and the water level starts to fall and the water level falls to the lower end level of the bell mouth 8, the pumping stops and no load state, so the rotational speed of the pump shaft 4 starts to rise .
(6) When the rotation speed of the impeller 6 reaches a preset upper limit value (for example, 99% value of the full speed rotation speed), a control signal is transmitted from the control device 12 and the clutch 5 is disconnected. The connection with the pump shaft 4 is cut off and the standby operation is performed again.
At this time, although the clutch 5 is disconnected, the power of the prime mover 9 is transmitted to the pump shaft 4 due to the viscosity of the lubricating oil existing between the clutch plates, and the pump shaft 4 rotates at a constant speed by corotation. There is.

(7) Water flows into the suction water tank 2, and the rise of the water level starts again.
(8) Then, when the water level rises to the lower end level of the impeller 6, it starts acting as a resistance to the rotational torque of the impeller 6, and the resistance gradually increases with the rise of the water level, and the rotational speed of the impeller 6 gradually decreases. .
(9) When the rotational speed of the impeller 6 reaches a preset lower limit (for example, the rotational speed of the pump shaft 4 when the entire impeller 6 is submerged (corresponding to the water level WL3)) A control signal is transmitted to the supply device 13, the clutch 5 is connected, the rotational power of the output shaft 10 is transmitted to the pump shaft 4, and the pumping operation is started.

(10) Then, the pumping operation is continued and the water level starts to fall, and when the water level falls to the lower end level of the bell mouth 8, the pumping stops and the unloaded state is started, so the rotational speed of the pump shaft 4 starts to rise.
(11) When the rotation speed of the impeller 6 reaches a preset upper limit (for example, 99% of the full speed rotation speed), a control signal is transmitted from the control device 12 and the clutch 5 is disconnected. The connection with the pump shaft 4 is cut off and the standby operation is performed again.
At this time, although the clutch 5 is disconnected, the power of the prime mover 9 is transmitted to the pump shaft 4 due to the viscosity of the lubricating oil existing between the clutch plates, and the pump shaft 4 rotates at a constant speed by corotation. There is.
The above steps are repeated while the preceding standby operation is required.

  As described above, in the vertical shaft pump 1 of the present embodiment, the rotational speed detected by the rotation detector 11 reaches a predetermined lower limit value in the state where the control device 12 is driving the motor 9 and the clutch 5 is disconnected. In the state where the clutch 5 is connected and the driving motor 9 is driven and the clutch 5 is connected when the pressure drops, when the rotational speed detected by the rotation detector 11 rises to a predetermined upper limit value, Since it disconnects, changes in the water level of the suction water tank 2 can be detected by changes in the rotational speed of the pump shaft 4, and connection and disconnection of the clutch 5 in the pre-waiting operation are automatically performed without providing water level detection means such as a water level gauge. It will be possible to

  That is, in the vertical shaft pump 1, with the clutch 5 interposed between the prime mover 9 and the pump shaft 4, the change in rotational speed due to the co-rotation of the pump shaft 4 when the prime mover 9 is driven and the clutch 5 is disconnected. Is detected and the clutch 5 is connected, and in a state where the vertical pump 1 is operated with the clutch 5 connected, a change in rotational speed of the pump shaft 4 is detected to disconnect the clutch 5.

  Therefore, the change in the water level of the suction water tank 2 can be reliably detected by the change in the rotational speed of the pump shaft 4, and the suction water tank 2 does not have to be provided with water level detection means such as a water level gauge. Therefore, operation control of the water level detection means does not disturb operation control due to malfunction such as malfunction or conduction failure, and it is possible to reliably detect a change in rotational speed accompanying a change in water level and to perform a leading standby operation. .

  Further, the lower limit value and the upper limit value of the rotational speed of the pump shaft 4 are set in advance, and when the detected value of the rotational speed of the pump shaft 4 falls below the lower limit value, the clutch 5 is connected and the value is increased above the upper limit value When the clutch 5 is disconnected, the control of the connection and disconnection of the clutch 5 can be reliably performed by appropriately setting the lower limit value and the upper limit value according to the specification of the vertical shaft pump 1, the installation situation, etc. As a result, a suitable preceding standby operation is possible.

  Next, a second embodiment of a vertical pump according to the present invention will be described below with reference to FIG. In the following description of the embodiment, the same components as those described in the above embodiment are denoted by the same reference numerals, and the description thereof is omitted.

The second embodiment differs from the first embodiment in that, in the first embodiment, the prime mover 9 is an electric motor, whereas in the vertical shaft pump 21 of the second embodiment, as shown in FIG. 3, the prime mover It is a point which makes 20 an internal combustion engine.
Further, in the second embodiment, the reduction gear 25 is provided between the prime mover 20, which is an internal combustion engine, and the clutch 22.

  That is, in the second embodiment, the hydraulic clutch 22 is interposed between the motor 20, which is an internal combustion engine, and the reduction gear 25, and the output shaft 23 of the reduction gear 25 and the pump shaft 24 are connected. Also in this configuration, the power of the prime mover 20 can be transmitted to the pump shaft 24 by connecting the clutch 22, and the transmission of the power of the motor 20, which is an internal combustion engine, is shut off by disconnecting the clutch 22. Can.

  Therefore, even in the vertical shaft pump 21 of the second embodiment, the leading standby operation can be performed by the same control method as that of the first embodiment by detecting the change in rotational speed when the pump shaft 24 corotations and during operation. it can.

In addition, this invention is not limited to said each embodiment, It is possible to add a various change in the range which does not deviate from the meaning of this invention.
For example, although the photoelectric rotation detector is used as the rotation detector for detecting the rotation speed of the pump shaft in the above embodiment, the present invention is not limited to this, and an electromagnetic rotation detector may be used.

  1, 21: Vertical pump, 4, 24: Pump shaft, 5, 22: Clutch, 6: Impeller, 9, 20: Motor, 11: Rotation detector, 12: Control device

Claims (4)

And a motor
A pump shaft rotationally driven by the motor;
An impeller provided below the pump shaft,
A clutch interposed between the motor and the pump shaft for transmitting and disconnecting the rotational power of the motor to and from the pump shaft;
A rotation detector for detecting the rotational speed of the pump shaft;
And a control device that controls the motor and the clutch.
In a state where the motor is driven and the clutch is disconnected, the pump shaft is driven by the rotational power of the motor transmitted through the viscous lubricating oil interposed between the clutch plates of the clutch. Can be turned,
The control device connects the clutch when the rotational speed detected by the rotation detector decreases to a predetermined lower limit value while the motor is being driven and the clutch is disconnected. An upright pump characterized in that the clutch is disconnected when the rotational speed detected by the rotation detector rises to a predetermined upper limit value in a state where a motor is driven and the clutch is connected. In the vertical pump according to claim 1,
A vertical shaft pump characterized in that the prime mover is an electric motor. In the vertical pump according to claim 1,
A vertical shaft pump characterized in that the prime mover is an internal combustion engine. It is an advance standby operation method of a vertical axis pump,
The vertical shaft pump is a prime mover,
A pump shaft rotationally driven by the motor;
An impeller provided below the pump shaft,
A clutch interposed between the motor and the pump shaft for transmitting and disconnecting the rotational power of the motor to and from the pump shaft;
And a rotation detector for detecting the rotational speed of the pump shaft,
The pump shaft is rotated by the rotational power of the prime mover transmitted through a viscous lubricating oil interposed between the pump shaft and the clutch in a state where the prime mover is driven and the clutch is disconnected. Is possible,
In a state where the motor is driven and the clutch is disconnected, the clutch is connected when the rotational speed detected by the rotation detector decreases to a predetermined lower limit value, and the motor is driven. And a clutch is disconnected, wherein the clutch is disconnected when the rotational speed detected by the rotation detector rises to a predetermined upper limit value.

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