JP2794983B2 - Water supply device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water supply device having an electric pump and a pressure tank, and more particularly to a protection device for a water supply device suitable for a system for preventing an overload operation of an electric motor due to a pump abnormality or other causes.

[0002]

2. Description of the Related Art Conventionally, detection of anhydrous operation or overload of a pump has been performed based on the operating current of a motor.
As this type of apparatus, there is Japanese Utility Model Laid-Open No. 52-98202. In this device, when a low operating current continues for a certain period of time by an ammeter with contacts, it is regarded as anhydrous operation and the motor is stopped. Conventionally, a thermal relay (thermal type) is generally used for overload protection of a motor.

[0003]

[0007] The above prior art, the overload protecting method for an electric motor according to Sa over <br/> Marurire is slow protection operation for the bimetal scheme, for the protection of utilizing relay contact Not sure.

[0004] Therefore, the present invention can prevent an electronic (contactless) overload failure of a water supply device , and in particular, modify its protection characteristics.
With the aim of providing a protective device for the water supply system
I have.

[0005]

The object of the present invention is to provide a pump ,
An electric motor for driving the pump, and a discharge side of the pump.
A connected water supply pipe, and a pressure detector provided in the water supply pipe;
Means for controlling the electric motor based on the signal of the pressure detecting means.
In a water supply device provided with control means for controlling operation,
Detecting means for detecting a load state of the electric motor;
Load factor and pump at the motor allowable load factor
Storage means for storing protection characteristics of motor allowable stop operation time
Setting means for setting a rated load value of the electric motor;
Correction of allowable stop operation time of pump motor with protection characteristics
Means for setting a protection characteristic correction value for
Pump motor allowable stop operation of the protection characteristic based on the positive value
Means for modifying the operation time to determine the modified protection properties;
The load state detected by the detection means is the motor rated negative.
Load of specified magnification of rated load value set by load value setting means
A time measuring means for measuring the operation time when the rate is exceeded;
The clock time of the time means
Stop the pump when the motive allowable stop operation time is exceeded
This is achieved by providing a water supply device characterized as described above.

[0006]

The control device constantly monitors the operating current, and stops the pump if the abnormal current has continued for a certain period of time (if necessary, the time is changed depending on the rate of increase and decrease of the current).

That is, the control / storage arithmetic processing section stores the pump / motor protection characteristics in advance, and corrects the protection characteristics as required by the motor allowable load factor setting means SW2 and the pump / motor allowable stop operation time. . Further, it is determined whether the value of the input port Pco is “1”. If the value is not “1”, the pump / motor is considered to be normal and normal operation is performed. The current transformers CT1 to CT of the load state detecting means determine the load state of the motor.
Detected by 3, this value is beyond the load factor described above, after a lapse of operating time described above, by switching the output mode input port Pco outputs data of "1".

Along with this, the transistor Q of the overload fault operation display and holding section is turned on, the keep relay KS is set, and the light emitting diode LD1 is turned on.
Further, the contact Sa is closed by setting the keep relay, and the output of the three-state buffer IC1 becomes "1". Next, switch Pco to the input mode,
Read the data here.

As a result, since the input from Pco is "1", the pump / motor is stopped immediately.

[0010] Even if the circuit breaker MB for wiring is turned off and then turned on again, the keep relay S remains set for mechanical holding, and its contact Sa remains closed. Thus, the output of IC1 as described above is "1", a protected operating state.

In this state, when the reset means SW4 is pressed, the reset is performed, the contact Sa is opened, and the output of the IC 1 is in a high impedance state. Since the input result of Pco is not "1", the operation returns to the normal operation.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

FIGS. 1 and 2 are block diagrams of a water supply apparatus according to an embodiment of the present invention.

In FIG. 1, R, S, and T are power supplies, MB is a circuit breaker, CT1, CT2, and CT3 are current transformers that detect a current flowing through a main circuit and transform the current to an appropriate minute current value.
MC is a coil of an electromagnetic contactor, Mca is its contact, and 3 is a motor.

R1 and S are control power supplied from the secondary side of the circuit breaker MB, SW1 is a switch for switching between automatic operation and stop / manual operation, T is a transformer, and Z is, for example, AC200.
This is a stabilized power supply unit that converts V AC to DC (5 V) of a constant voltage and supplies it.

The PCB is a printed circuit board on which a control / storage operation processing section is mounted, and the MPU is a microprocessor generally called a one-chip microcomputer (hereinafter abbreviated as a microcomputer), a central processing unit, a memory, an input / output port PA.
To PF, A / D converter, etc. B is a clock generator, which comprises a crystal CL, a resistor R1, and capacitors C3 and C4.

F1 to F3 are interface units for connecting to the above-mentioned input / output ports.
Is a setting means for setting the rated current of the motor, for example, an 8-bit dip switch. Similarly, SW3 is a setting means for setting a protection characteristic correction value, for example, an 8-bit dip switch.

The interface F1 is a current transformer C
The operating current I of the motor 3 detected by T is converted into a DC voltage for input to the analog input ports AN0 to AN2 of the microcomputer, and the value is read and stored in the memory.

PS is a contact point of the pressure switch 8 (FIG. 2), and is connected to the input / output port PA via the interface F2.
Read from 0 and store in memory. Further, the electromagnetic contactor M is connected from the input / output port PB0 via the interface F3.
Outputs data for ON-OFF control of C.

M denotes an overload fault operation display and holding unit, and a keep relay KR, a transistor Q, a resistor R
2, R3, R4, diodes D1, D2, light emitting diode LD1, three-state buffer IC1, and reset switch SW4. The reset switch SW4 is for resetting the keep relay KR (mechanical holding), and the buffer IC1 outputs three states of 0, 1, and high impedance.

In FIG. 2, 1 is a water receiving tank, 2 is a water absorption pipe,
3 is an electric motor, 4 is a pump, 5 is a gate valve, 6 is a check valve,
7 is a pressure tank having an air reservoir therein, 8 is a pressure switch, 9 is a water supply pipe, and 10 is a control circuit shown in FIG.

FIG. 3 is a pump operation characteristic diagram of the water supply apparatus of the present embodiment, in which the vertical axis represents the pressure H and the horizontal axis represents the water amount Q. In the figure, curve A represents the QH characteristic of the pump, curve B represents the load curve of the motor, that is, the current curve, P1 represents the starting pressure of the pump, and Q1 represents the pumping amount at that time. The pressure switch 8 described above is set to close at P1 and open at the return pressure P2. It is the rated current of the motor,
As will be described later, it is set in advance in the memory of the microcomputer or externally set by a dip switch (not shown).

FIG. 4 shows an example of a protection characteristic diagram of the motor.
The vertical axis shows the motor allowable load factor, and the horizontal axis shows the pump motor allowable stop operation time. Curve a is its protective properties,
It is stored in the memory of the microcomputer in advance as an initial value. When the protection characteristic is corrected by the outside air temperature or the like, for example, an arbitrary correction line is provided on the allowable load factor coordinate. This may be stored in a memory in advance, or may be set by a dip switch or the like (not shown).

In this embodiment, the point of 300% is shown as a protection correction line. The initial set value of SW3 is t3, but if it is changed to t3 ', curve A is shifted from 0 to point 01, and curve A becomes curve B.

FIGS. 5 to 10 are flow charts showing the operation procedure of the control device shown in FIG. 1 according to the embodiment of the present invention.
The operation of the water supply device will be described in detail with reference to this drawing.

In FIG. 1, when the circuit breaker MB is turned on, the microcomputer power supply rises in the order of T → Z and starts operation. First, the stack pointer of step 501 in FIG.
Perform initial settings such as input / output ports, timer interrupts, and analog interrupts.

In step 502, the protection characteristic shown in FIG. 4 is stored in the memory as a curve A, for example, as a function.
Further, as described above, data is read from the memories MSW2 and MSW3 in which the data of the setting means SW2 and SW3 are stored, and the curve A is corrected. Then, for example, 1.3 times, 2.0 times, 3.0 times, and 6.0 times are calculated from the data of the switch SW2 for setting the rated value of the motor load factor, and the result is stored in the memories MSW4 to MSW7. Using the function after the correction, the allowable stop operation time is stored, and the load ratio 13
The value is automatically set by substituting values of 0%, 200%, 300%, and 600% to obtain an inverse function.

As a result, t1, t2, t3, and t4 are stored in the memories TIME0 to MTIME6. And 503
The step executes a soft timer (for example, 100 ms) to prepare for the timer and the analog interrupt processing.

For example, if the timer interruption period is set to 20 ms at the time of initial setting, a timer interruption occurs during the soft timer processing, and the processing of FIG. 6 is executed. That is, in step 602, the analog interrupt is prohibited so as not to occur, and in step 603, the data of SW2 and SW3 described above is read and stored in, for example, the memories MSW2 and MSW3.

In step 604, SW1 shown in FIG.
A subroutine for PS determination is called to determine the position of SW1 and ON / OFF of the pressure switch PS. The result is stored in the memories MSW1 and MSW2, for example, as follows. MSW1: OOH ... Manual FFH ... Automatic MSW2: OOH ... OFF FFH ... ON Similarly, in step 605, the pump shown in FIGS.
The load factor of the motor and the operation time of the motor are checked to execute a subroutine for determining whether an overload has occurred or is normal.

9 and 10, in step 902, the input / output port Pco is set to the input mode. And
In step 903, it is determined whether Pco is "1".
If it is "1", it jumps to step 914 because it is abnormal, and FFH (meaning of abnormal) is set in the memory MNGP.

If it is not "1", the process proceeds to step 904, where the minimum value of the current detected by the current transformers CT1 to CT3 is obtained in step 910. 10H (when analog input is performed in the open phase state, the value does not become 00H due to the wiring stray capacitance . If it is smaller than this, it means an open phase (any of the three phases), so the duration of this state is counted in step 910.

For example, as will be described later, a memory MTIMF (8 bits) is prepared as a flag for starting and stopping the timer. Naturally, this value is set to 00H in the initial setting. Here, bo is set to “1” to start the phase loss operation timer MTIME0. 606 to 60 in FIG.
In eight steps, the flag bo bit is checked to see if it is "1", and the countdown (step 607) is performed.

That is, this timer has an interrupt cycle (2 in this example).
0 ms). Therefore, the timer M
TIME0 to MTIME6 are configured by 2-byte memories.

In step 911, it is determined whether the result of the countdown is "0". If it is "0", it means that the open-phase operation has elapsed for a predetermined time. In step 912, the input / output port Pco is switched to the output mode. In step 913, "1" is output to the input / output port Pco, FFH is set in MNGP, and 917-9
Exit from this loop through 18 steps.

If the above loop has not been passed, 91
Proceed to step 5 to determine the reverse phase and overload. 915
The data of the current passed to the step is transferred to the A register, and the load factor is 130% in step 916 (memory MSW
Entered the 4 are) to determine whether less than or greater, because if small, normal operation passing to 917 steps later-flops. If it is larger, the process proceeds to step 919 (FIG. 10), and it is determined whether the load factor is 200% or more this time. If it is smaller, a timer for measuring the operation time at the load factor is started in step 920.

At step 921, it is determined whether or not the timer is counted down to "0". If not, the process goes through steps 917 to 918 to exit this loop.
If 0, the process proceeds to step 912 to execute the above-described operation.

Although the description is omitted, the load factor is 300%, 600%
In the case of%, the same operation is performed by the processing after step 922. By executing the above processing, the timer interrupt 61 in FIG.
Allow interrupts in 5 steps and exit. Therefore, an analog interrupt is executed next.

[0039] In Fig. 7, the load current 703 step detected by CT1 to CT3, memory MAN0~MA
Store it in N2.

After executing the soft timer process of step 503, the process proceeds to step 504, and it is determined whether SW1 is closed to the K side. If it is closed on the K side, the data in the memory MSW1 is FFH, so the process proceeds to the next step 505. If not closed, "auto" for 504 steps
It is repeatedly executed until it is set to (K side). further,
In step 505, it is determined whether the contact of the pressure switch PS is closed. When closed, the data in the memory MSW2 is FFH. Therefore, if it is FFH, the process proceeds to the next step 507. The data in the memory MSW2 is FF
If not H, the process returns to step 504, and the process is executed again from here.

In step 507, as described above, in the timer interrupt processing, the load current of the motor is detected, and based on the relationship between the predetermined load factor and the operation time, whether or not the overload failure has occurred. If the NGP data is 00H, jump to step 506 and issue a pump stop command if the NGP data is 00H. And do not start the pump. Next 50 if FFH
Start the pump in 8 steps.

Next, at step 509, the pressure switch is turned off.
It is determined whether or not the pump is in the F state. If it is in the ON state, the process returns to step 507, and the pump continues to operate. if,
During this loop, when the overload is detected and the memory NGP is set to 00H in the aforementioned timer interrupt processing, 5
Proceed to step 06, where the pump is emergency stopped. Thereafter, the process returns to step 504 to execute the subsequent processes and repeats until the value of the memory NGP is FFH (reset).

In this state, even if the power supply is reset by mistake, the keep relay KP of FIG. 1 is set and the contact sa is closed as described above.
The value input from the input port Pco is “1”, and the state of the overload fault is maintained. In this state, if the reset switch SW4 is pressed, the reset coil R is excited, the contact sa opens, the input of the input / output port Pco becomes a high impedance state, and the overload fault is reset. Next, as a result of the determination in step 509, if the pressure switch is turned off and the data of MSW2 is "0", the process proceeds to step 510, and the pump is stopped. Then, returning to step 503, the above-described operation is repeatedly executed.

Next, another embodiment of the present invention will be described with reference to FIGS.
This will be described below. In the present embodiment, the water supply device, a plurality of pumps each driven by an electric motor, a detecting means for detecting a load state of the electric motor, and calculating a load factor of the electric motor based on an output of the detecting means, A protection unit that performs a protection operation of the electric motor based on a protection characteristic determined by a relationship between the load factor and the allowable operation time. The protection unit temporarily stops the operation of the pump when an abnormality occurs, and switches to the other pump. It is configured to drive the vehicle.

In this embodiment, motors are connected to the pump 1 and the pump 2, respectively, and the currents of the motors of the pump 1 and the pump 2 are respectively CT1, CT2, CT3 and CT3.
As shown in FIG. 13, the controller as protection means calculates a load factor based on this output, and the protection determined by the relationship between this load factor and the allowable operation time determined by a preset rated current as shown in FIG. The protection operation of the electric motor is performed based on the characteristics.

In this protection operation, as shown in FIG. 12, a retry operation is performed, that is, an operation of temporarily stopping the operation of the pump before completely shutting down and switching to the other pump for operation is performed. If it is performed three times, it is regarded as abnormal and an emergency stop is performed.

Thus, the motor can be protected by detecting the overload and the water drop electrically.

As a safety measure, as in the above-described embodiment, once the protection device has been activated, the pump is made inoperable unless it is reset artificially, and the state is maintained even when the power is turned off.

[0049]

According to the present invention, the pump is stopped by detecting the load state of the electric motor, since it is configured as described above.
Not only can the pump motor be reliably protected ,
The ambient environment and operating conditions, since the protective properties can be modified by an external setting, the effect of improving the usability.

[Brief description of the drawings]

FIG. 1 is a control circuit diagram of a water supply device according to an embodiment of the present invention.

FIG. 2 is a system diagram of a water supply device of the present embodiment.

FIG. 3 is an operation characteristic diagram of the pump according to the embodiment.

FIG. 4 is a protection characteristic diagram of an example of an electric motor.

FIG. 5 is a flowchart showing a control procedure of a control circuit of the water supply device of the embodiment.

FIG. 6 is a flowchart showing a control procedure of a control circuit of the water supply device of the embodiment.

FIG. 7 is a flowchart showing a control procedure of a control circuit of the water supply device of the embodiment.

FIG. 8 is a flowchart showing a control procedure of a control circuit of the water supply device of the embodiment.

FIG. 9 is a flowchart illustrating a control procedure of a control circuit of the water supply device according to the embodiment.

FIG. 10 is a flowchart showing a control procedure of a control circuit of the water supply device of the embodiment.

FIG. 11 is a block diagram showing the configuration of a second embodiment of the present invention.

FIG. 12 is a diagram showing an operation range of the present embodiment.

FIG. 13 is a flowchart showing an operation flow of the embodiment.

[Explanation of symbols]

3: motor, 4: pump, 7: pressure tank, 8: pressure switch, 9: water supply pipe, CT-1 to CT-3: current transformer (current detection means), MC: electromagnetic contactor, PCB: printed circuit board , Mpu: microprocessor, M: overload fault operation display holding circuit, SW4: reset switch, SW2: rated load factor setting means, SW3: operating time setting means

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) F04D 15/00 F04B 49/06 321 F04B 49/10 311

Claims (1)

(57) [Claims] 1. A pump and an electric motor for driving the pump
A water supply pipe connected to a discharge side of the pump;
A pressure detecting means provided in the water pipe;
Control means for controlling the operation of the motor based on the signal;
In the water supply apparatus was example, a detecting means for detecting a load state of the electric motor, the electric
The allowable load factor of the motor and the pump at the allowable load factor of the motor.
Memory for storing the protection characteristics of the motor allowable stop operation time
Stage, setting means for setting a rated load value of the electric motor,
Correct the pump motor allowable stop operation time of the protection characteristic.
Means for setting a protection characteristic correction value for the protection characteristic,
Pump motor permissible stop of the protection characteristic based on the correction value
Means for modifying operating time to determine modified protection characteristics
And the load state detected by the detection means is the motor state.
Rated load value set by the rated load value setting means.
A timing means for timing the operation time when the load factor is exceeded;
The clock time of the clock means has the modified protection characteristic.
The pump is stopped when the motor
A water supply device, characterized in that the water supply device is adapted to be provided.