JPS59200095A - Liquid supply device - Google Patents

Abstract

PURPOSE:To make it possible to continue a stable control operation of a pump, by comparing a target pressure of the pump with a measured pressure thereof, and increasing or decreasing a liquid supply capacity on the basis of a result of judgement whether or not both the pressures are in the relation of under-capacity or over-capacity of liquid supply of the pump. CONSTITUTION:When a detection pressure of a pressure sensor PS is judged to reach a prestored pressure H1, a pump P1 is started. With a delay time of several seconds after start of the pump, when the detection pressure of the pressure sensor PS is judged to reach a prestored pressure H4 for commanding stoppage and decrease in a number of the pump, a stop command of the pump P1 is executed, while if being judged not to reach the pressure H4, it is judged whether or not the detection pressure reaches the pressure H1 for commanding start and increase in the number of the pump. Then, if it reaches the pressure H1, it is commanded to operate a pump P2 in addition to the pump P1, while if a pressure in a pressure tank T is judged to reach the pressure H4, it is commanded not to operated the pump P2. Thusly, it is possible to continue a stable control operation at all times.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a water supply device, and particularly to a water supply device equipped with an operation control device that can efficiently control operation.

[Background of the invention]

A small-capacity pressure tank is installed on the discharge side of multiple pumps, and water is supplied by controlling the number of multiple pumps in accordance with the pressure inside the pressure tank. . Pumps are also operated at variable speeds depending on the amount of water demanded. To explain an example of such a liquid supply device, FIG. 1 is a block diagram showing a +f5 configuration of the water supply device.

~P4 is the pump, CH, ~OH, is the check valve, SL, ~
SL4 is the gate valve, DP is the water supply pipe, T is the secondary tank, PS
L and PsH are pressure switches.

Incidentally, subscripts 1 to 4 indicate pump numbers, and this example has a configuration of four pumps. Fig. 2 is a diagram showing the operating characteristics of the Ikazu pump, with the pressure H on the vertical axis and the water amount Q on the horizontal axis. curve a
This shows the average individual performance of four pumps (the performance of the four pumps is considered to be almost the same).

Hereinafter, the curve S shows the composite performance of two pumps, the curve C shows the combined performance of three pumps, and the curve d shows the combined performance of four pumps when operated in parallel. Further, pressures H5 to H4 each indicate the operating pressure, and the pressure switch PSL described above is set to close at pressure H7 and open at pressure H2, and similarly, pressure switch PSH is set to close at pressure H3 and open at pressure H4. o Qa, Q, 1), Q, h, Q
g indicates the amount of water at each operating pressure point.

For convenience, it is now assumed that the pressure in the pressure tank T has reached H4 and all pumps have stopped. From this state, the water is consumed and the pressure decreases, and when the pressure reaches H1, both pressure switches PSH and PSL close, for example, pump P,
starts. When the amount of water used is low and the pressure in the pressure tank T reaches H4, the pump P that started will stop, but the amount of water used continues to be large, and after starting pump P, the -1 fixed time required to start up the operation of this pump P will be stopped. Even if the pressure inside the pressure tank T is between H1 and H2
In the meantime, a pump that is at rest, for example P2, is brightened. If the pressure in the pressure tank T exceeds H2 and is less than H4, the 1,000 ka switch PSL will be open and the platform will not change.
The amount of water used decreases, the pressure inside the pressure tank T reaches H4, and the pressure switch PSE is activated.

If both PSLs open and this state continues even after a certain period of time has elapsed, one of the operating pumps, for example P, will be mounted.

However, in such a liquid supply device, if the discharge pressure changes in a pulse-like manner for some reason, or if an erroneous signal is generated due to disturbance, a pump increase/decrease command is output, and the pump's chattering operation may occur. This could lead to unstable pump operation.

Further, in contrast to the control device using such a relay set, an analog feedback control device that constantly compares the target pressure and the discharge pressure has also been proposed. However, with this control device, the control circuit had to be designed according to the model of the liquid supply device, and there were drawbacks such as the inability to reduce the cost of the product system and the inability to necessarily obtain appropriate control characteristics. .

[Purpose of the invention]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a water supply device equipped with a control device having good control characteristics.

[Summary of the invention]

That is, the present invention provides a pump, a drive device that drives the pump, a pressure sensor connected to the discharge side of the pump, a storage device that sets a target discharge pressure of the pump, and a target pressure stored in the storage device. and a direction determining means for determining whether the two have a predetermined relationship, and based on the determination result of the direction determining means, the driving device is configured to determine the liquid supply capacity of the pump. The present invention provides a liquid supply device that is equipped with a control device that outputs an increase/decrease command signal, and is capable of operating the pump at an appropriate variable speed according to changes in the load.

Furthermore, the present invention provides a liquid supply device that reliably captures changes in load even when controlling a group of pumps consisting of a plurality of pumps, and controls the number of pumps in the group.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be explained with reference to FIGS. 3 to 9. Figure 5 is a block diagram showing the configuration of a water supply (liquid) system when controlling a pump group consisting of six pumps with almost the same performance. Parts indicated by the same symbols as in Figure 1, which have already been explained, have the same functions. It is something that does. Note that PS is a pressure sensor that detects the pressure within the pressure tank T and water supply pipe DP, and emits a DC electrical signal in response to this. FIG. 4 is a diagram showing the operating characteristics of the pump, and the same reference numerals as in FIG. 2, which have already been explained, have the same meanings, so a description thereof will be omitted. Here, Hl is the pump starting and whitening command pressure, H,, H
3 is a pressure preset around pressure H8 with a width several times the resolution of the control system, which will be explained in detail later.

Similarly, 1cH4 is the pump stop and platform command pressure, H,,H.

is a pressure set in advance around pressure H4 with a range several times the decomposed persimmon of the control system. Note that these set pressures are determined in advance with reference to the pump characteristic curve, and the actual setting procedure will be explained in detail later. Also, Qa
'l Qa'l Qbs Qg indicates the flow rate corresponding to these set pressures. Figure 5 shows the main circuit of the control device, where PW is the power supply, MOB is the wiring breaker, MC, ~MC
2 is an electromagnetic contactor, TH, ~TH, is a thermal relay, M
, ~M4 is a motor that drives a pump (not shown), R
, S is the operating power supply to the control circuit. Here subscripts 1 to 4
indicates the pump number. Figure 6 shows a microcomputer (hereinafter referred to as μcon) and its peripheral circuits, which are part of the control circuit of the control device. P engineering Aa, P engineering Ab, PIAc.

PIAd, consists of power input terminal E. Further, F is an interface including an A/D 7#'1% unit for reading the signal from the pressure sensor ps into the μcon, and similarly, F2 is a command signal from the μcon (pump increase/decrease command signal). An interface for outputting S, to relays X, ~X4 via input/output port P Ab.
It's Kuntafa Ace. By the way, relay X is energized when data 0' (+61) is output from P At:, and similarly, relays X2, x8, and X4 each have data 02 (+6) * 04 (16),
energized when Q8(1,,) is output.Furthermore, D
S, , DS represent 13-bit switches for setting the above-mentioned pressures H, , I(4), and the settings are stored in the memory (RAM) of the μcon.

Figure 7 also shows a drive circuit for multiple pump motors, which is part of the control circuit, and shows the electromagnetic contactor MCl-MC4 and the relay X.
, ~X4 contacts. In other words, relays X and ~X4 are energized and the same contact b M O+~MC4 is energized 0. Also, Fig. 8 shows the relationship between the pressure detected by pressure sensor PS and the electrical signal transmitted. .

In this embodiment, a DC voltage output (3) is shown, but a current signal may also be used. FIG. 9 is a flowchart showing the basic procedure of the operation of the embodiment, and FIG. 10 is a flowchart showing the detailed procedure of operation. Of course, it is necessary to memorize the program.

Now, a detailed explanation will be given with reference to these drawings.

First, the basic operation of the embodiment will be explained with reference to FIG. 9. After initial setting, the control device takes in the current discharge pressure from the pressure sensor ps, and the discharge pressure is in the range of pressure H7 to pressure H4. is outside this range, and if it is outside the range, the next step is to determine whether the discharge pressure tends to be lower than the start and whitening command pressure H5, or to increase from the stop and platform command pressure H4. Determine whether there is a tendency to In this way, after determining which direction (decrease or increase) the change in discharge pressure is heading from the pressure range of the target discharge pressure, the number of operating pumps is changed. In other words, if it is determined that the discharge pressure tends to fall below the target discharge pressure range, if all pumps are stopped, the pumps are started, and the pumps are already running. If necessary, additionally start other pumps. Similarly, if it is determined that the target discharge pressure tends to exceed the range, if multiple pumps are being operated,
) + P. Nobukun 111 Shun L1 Seji)---mu f
When the engine is running, it is stopped.

The embodiment will be described in detail below with reference to FIG. 10. Immediately, in 1 to 2 steps, the starting and whitening pressure H1 set by the switch DSI is read and stored in the address Ml (RAM) of the memory M of μcon via the input/output capo-4P, and the same process is performed. Then, in 3 to 4 steps, the stop and platform pressure H4 set by the switch DS2 is read and stored in the address M (RAM). Next, in 5 steps, the pressure in the pressure tank T or water supply pipe DP detected by the pressure sensor ps is read, converted into digital, and loaded into the A register. Next, in 6 steps, it is determined whether the pressure has reached the pressure set lower by the pressure corresponding to the resolution of the control system (specifically, the value obtained by decrementing the digitally converted pressure H4 value once), and
If it is below, execute the processing instructions after step 14, and
If the pressure has reached 6, proceed to the next 7 steps, wait for △t (several m5ec) (sufficient time to detect a pressure change), and then stop at step 8.9. Then, it is determined whether the platform pressure H4 has been reached, and if it has not reached it, the processing commands after the 1A step are executed.
), and in the next 11 to 12 steps, it is determined whether the pressure has reached H6 (the value obtained by incrementing the digitally converted pressure H4 value once). Execute the processing command, and if the number has been reached, execute the 13-step processing command.

At this point, only one machine is installed from the number of machines currently in operation.

Then, a wait time t of several seconds is executed in step 25, and the process returns to step 5, from which the processing command is executed again. Here, the waiting time t corresponds to the time required for the pump to complete a starting or stopping operation based on a new command. For more details, if you mark 1, the amount of water used will decrease,
The pressure inside the pressure tank T gradually rises and reaches H4,
After this, if the determination result in the next step 121) is lower than H5, the whitening determination command shown in FIG.

In other words, the pressure before and after H4 is measured, and the change in pressure is confirmed. The device is designed so that it will not be placed on the stand if it is heading towards a decline).

Continuing the explanation, in step 14, the output signal of the number of units currently in operation is output from the input/output port P Ab of μCCn without being converted, and then in step 15 and 16, the pressure in the pressure tank T is set to H. , (the value obtained by incrementing the digitally converted pressure H8 value once) is determined. If it has not been reached, proceed to the 2A step, and if it has been reached, proceed to the next 17 steps to determine △t (several m5ec). ), the processing command in step 18.19 is executed to determine whether the pressure in the pressure tank T has reached Hl. If it has not reached it, proceed to step 2A, if it has reached it, proceed to 20 steps △t (several meecs)
After executing the waiting time, H is pressed again in steps 21 and 22.
2 (the value obtained by decrementing the digitally converted pressure H, once). If not, execute the processing commands from the 24th step onward as described above. If the value has been reached, execute the processing from the 23rd step. Execute commands. and,
Here, the number of machines that are currently in operation is increased by one machine. Thereafter, a wait time t of several seconds is executed in step 25, and the process returns to step 5, whereupon the processing command is executed again. To explain in more detail, even if the amount of water used gradually increases and the pressure in the pressure tank T decreases in the order of H, H, then if the pressure rises to H1 or higher due to a sudden change in the amount of water used, does not brighten, and this time executes the platform determination processing command shown in A. That is, the pressure before and after the whitening pressure H1 is measured, and the change in direction is confirmed, and the pressure is determined to be H3.
, H, , H2, whitening is performed only when the pressure decreases, and whitening is not performed when the pressure changes midway and tends to rise.

As described above, according to this embodiment, there is no need for a plurality of pressure switches, and the adjustment is easy and highly reliable.

Furthermore, since it does not depend on a flow rate switch or the like, a low-cost pump device can be obtained.

Next, a second embodiment will be explained with reference to FIG.

In this embodiment, a pressure sensor detects a sudden pressure change to prevent an erroneous command from being issued.

That is, the operation may be controlled as shown in FIG.

Figure C shows a modified version of the A part in Figure 10, and Figure 2 shows a modified version of the mouth part in Figure 10. Other than this, all the instructions are the same as those in FIG. 10 and have the same procedure. In the same figure C, the signal of the pressure sensor Ps is read and loaded into the A register in the A step, the loaded signal is transferred to the B register in the B step, and the memo IJM is stopped and the mounting table command pressure is set in the C step. Type H4 into the A register. next,
In the D step, the data in the B register is subtracted from the A register and temporarily stored in the A register, and in the E step, this difference is calculated as nbits (generally, nbits) of the resolution of the control system.

That is, the number of operating units is maintained at the current state until the pressure detected by the pressure sensor ps increases by nbits (2 to 5 bits) from the stop and platform command pressure H4, and nl)i'e
(2 to 3 bits), the mounting stage or stop processing is executed. Furthermore, although the detailed explanation will be omitted, in FIG.
When the number of operating vehicles decreases by (2-3 bits), the number of operating vehicles is maintained at the current state, and when the number decreases by more than n bits (2-3 bits), whitening or startup processing is executed.

This eliminates the need for a timer around μCon, and prevents the pressure sensor from detecting sudden changes in pressure and issuing erroneous commands.

Combining the above method with the first embodiment, 2 in Fig. 10
The waiting time t of 5 steps may be omitted, the step C in FIG. 11 may be executed after executing the 13-step loading command, and the step 2 in FIG. 11 may be executed after executing the 23-step whitening instruction.

Now, the third embodiment will be explained with reference to the drawings cited in the first embodiment and FIGS. 12 and 13.

FIG. 12 shows an operating characteristic diagram of this embodiment.
□7 The pipe resistance curve of the water supply pipe DP is added to Fig. 4, and the same reference numerals have the same meanings, so the explanation will be omitted.

Here, the pressure H1 is the starting pressure of the first pump and the bottle stand command pressure of the second pump, and the pressure H2 is the command pressure for increasing the third pump.
Pressure H3 indicates the bottle stand command pressure of the fourth gold pump. These operating pressures are set higher as the whitening command is issued along the resistance curve. FIG. 13 is a flowchart showing the operating procedure. Of course, a program is stored in the μcon so that the pump device can operate properly. For example, in the 50th step, when μcon determines that the pressure detected by the pressure sensor PS has reached the pre-stored pressure H1,
Start the No. pump, wait a few seconds t after starting,
In step 53, when it is determined that the pressure detected by the pressure sensor PS has reached the pre-stored stop and platform command pressure H4, in step 51, a command to stop the No. 1 pump is executed and the pressure has reached H4. If it is determined that there is not, in the next step 55, it is determined whether the starting and bottle stand command pressure H1 has been reached, as described above, and if it has been reached, in step 56, in addition to the No. 1 pump Pl, the No. 2 pump P is increased. White is commanded, and at step 58 the pressure inside the pressure tank T stops and the platform command pressure H4
If it is determined that the whitening has been reached, the No. 2 pump P
, commands the loading stage. Furthermore, if it is determined that the bottle stand command pressure H, has been reached in 60 steps, the No. 1 pump P,
In addition to the operation of No. 2 pump P2, No. 3 pump P, +7)
It commands whitening, then sequentially commands the pump to whiten each time it starts and reaches the whitening command pressure, and sequentially commands the pump to be mounted on the pump each time it stops or reaches the stage command pressure.

Although detailed explanation is omitted in this embodiment, K and pressure values H,, H, are the same as in the previously described embodiments.

When comparing the discharge pressure via Hs + H4 and the pressure sensor ps, determine what state of change the discharge pressure is in, that is, the direction of the pressure change from port 49 in Fig. 10 or port 49 in Fig. 11. C. Of course, it can be determined using the methods described in 2. According to such an embodiment, the pressure change on the water demand side can be gradually reduced.

In the embodiment described above, when the discharge pressure is outside the discharge target pressure range, the directional relationship between the target pressure and the discharge pressure is determined by the start Φ whitening command pressure or the stop/mounting command pressure ( By comparing multiple pressure values set before and after (hereinafter referred to as target pressure), or by changing the discharge pressure in a constant relationship by a certain width with respect to the target pressure,
Although the method for controlling the start and stop of the pump has been described, the following method may also be considered in order to determine the directional relationship of pressure change. That is, a whitening direction counter and a mounting table direction counter are provided, and when the discharge pressure is outside the target pressure range, the discharge pressure is measured every minute time (several m5ec), and the discharge pressure is lower than the target pressure range. When the brightening direction counter is incremented, and when the discharge pressure is higher than the target pressure range, the mounting table direction counter is incremented, and the value of the brightening direction counter is set to a predetermined value (an arbitrarily determined value, for example, 6). ), the whitening control of the pump can be performed, and conversely, the pump can be controlled to be mounted when the value of the mounting stage direction counter exceeds a predetermined value.

Of course, in this case, both counters are initialized when the discharge pressure is detected within the target pressure range, or after the number of machines is controlled. hand,
Although the explanation has been given of a device that maintains the discharge pressure within the target pressure range, this can be similarly applied to a liquid supply device that performs speed control. Hereinafter, such an example will be described as the first example.
This will be explained with reference to FIGS. 4 to 17.

FIG. 15 shows an operating characteristic diagram of the pump, where ΔH indicates hysteresis with respect to the target pressure H6, which is set in a pressure range corresponding to approximately 2 to 3 bits of resolution of the control system. Note that H8 indicates the upper limit value of the target pressure H6, and H2 similarly indicates the lower limit value. Also, curve a shows the Q-H performance when the operating speed is the maximum speed Nmax, and similarly, curve if shows the Q-H performance when the operating speed is the minimum speed H=□1. Fig. 16 shows the control device of the embodiment, where MCB is the breaker for the main circuit, MO is the coil of the electromagnetic contactor, MOa is the contact point, and NV is the variable frequency for changing the rotation speed of the variable speed motor M. Inverter device (Although an inverter device is used in this embodiment, a primary voltage control device, a fifth current joint, or other variable speed control device may be used as a means for changing the rotational speed of the drive motor of the pump P.) TH is This is a thermal relay for load protection. The configuration of the microcomputer μcon is the same as that of the embodiment described above, so a description thereof will be omitted. F, is an interface for sending the speed command signal (pump increase/deceleration command signal) 82 from the μcon to the input terminal of the inverter device INV, Y is a transformer T, power supply unit z1 start/stop switch SS, electromagnetic contactor MC .

- It is a control circuit consisting of a transistor Tr and a relay X. Note that the pace of the transistor Tr is the μc
It is connected to the signal line A of the input/output boat P engineering AC (8 bits) of on, and is connected to the signal line A. When obit becomes 1, the transistor Tr becomes conductive, and the relay X and the electromagnetic contactor MO are energized. In the control circuit Y, when the breaker MOB is turned on and the start/stop switch SS is closed, stable power that has been rectified and smoothed is sent from the power supply unit z via the transformer T to the power supply terminal E of μcon to prepare for operation. is completed. Figure 17 is the first
12 is a flowchart showing the control procedure of the fourth embodiment.

To explain in more detail with reference to these drawings, a program is stored in the memory M of μcan for operating the pump device according to FIG. 17.

That is, in this embodiment, the program is configured to determine whether the discharge pressure is increasing or decreasing with respect to the target pressure when the pressure exceeds the range from pressure 1 to pressure H7. be. In the figure, in one step, the pressure inside the water supply pipe DP is detected by the pressure sensor PS, read from the input/output boat P of μcan via the interface F, and loaded into the A register. Then, in two steps, the upper limit H of the target pressure H6 is
1 to the B register and compare the two in 6 steps. As a result of the comparison, the pressure inside the water supply pipe DP is equal to the pressure H1.
If it is larger, deceleration processing A is executed. If it is not large, proceed to the next 10 steps. In deceleration processing A, 4~
In 6 steps, the current driving speed is set to the lower limit of the shiftable range N1 to prevent runaway. Check if m has been reached, and if not, proceed to the next 7 steps. In addition, memo lJM
x contains shift command data. In the 7th step, only 1 bit is subtracted from the current operating speed, and in the next 8 steps, the subtracted data is transferred from the input/output port P of the μcon to the variable frequency inverter R unit NV via the interface F2. Send to input terminal. At this time, the variable frequency inverter supplies electric power to the motor IM at a frequency corresponding to the sent signal. Therefore, the motor M continues to operate at a speed corresponding to this. Next, μcon is 9
In this step, the speed commanded just now is stored in the memory MX as a new speed, and the process proceeds to the next 14 steps. As a result of the determination in 3 steps, if it is determined that the pressure in the water supply pipe DP is equal to or smaller than Hl, the commands from the 10th step onward are executed. That is, in step IQ, 11, the lower limit value H2 of the target pressure H8 is compared with the pressure in the water supply pipe DP. As a result of the comparison, if the pressure in the water supply pipe DP is large, execute the command in step 12.13 and proceed to step 14 without changing gears. executes the speed-up processing port.

In order to prevent runaway in steps 15 to 17, check if the speed at which you are currently driving has reached the upper limit value Nrrxsx of the shift range. If not, proceed to the next speed at steps 18 to 19. 11) Execute the speed increasing process by "it" and store the just-instructed speed in the memory lJMx as a new speed in 20 steps. In this way, the updated shift command data is always stored next in the memory Mx. Next, μcon executes the waiting time t necessary for speed control of the pump P1 motor M in 14 steps, returns to step 1 again, and repeats the above operation, until the pressure in the water supply pipe is greater than Hl. If the speed is reduced,
') If it is smaller than H2, the speed is increased, and the speed is not changed between H1 and H2.

Now, next, we will discuss still another example. 5th゜6th. This will be explained with reference to FIGS. 8, 14, 16, and 18.

FIG. 18 is an operating characteristic diagram of the pump of the embodiment, excluding the hysteresis with respect to the target pressure shown in the characteristic diagram of FIG. 15. FIG. 9 is a flowchart showing the control procedure of the embodiment. Of course, it is assumed that the memory M of μccn of the control device shown in FIG. 16 contains a program so that the control can proceed according to this procedure. In this embodiment, the direction of pressure change with respect to the target value H6 is determined. The comparison value for this is calculated arithmetically within the microcomputer. In Figure 19, D in 21 steps.
Clear the register to 0, detect the pressure in the water supply pipe DP in step 22, load it to register A, and temporarily store the data in register F in step 26. Next, in 24 steps, the data in the D register is subtracted from the data in the A register and stored in the A register.
The data in the E register, which was temporarily stored in the step, is now transferred to the D register, and in the 26th step, the data in the A register is transferred to the resolution of the control system, which is 2bj,t (approximately 2 to 3
Determine whether the pressure is larger than the value corresponding to (determined to be about 1 bit), and if it is smaller, execute Loopl without changing the gear until it becomes large.If the pressure in the standby water pipe DP changes by 2 bits or more, execute steps 30 and onwards. The changed pressure is compared with the target pressure Ho, and speed control is performed so that they match. It should be noted that the specific contents of the increase/deceleration process 41 are the same as those in the embodiment described in FIG. 17, so a description thereof will be omitted.

According to such an embodiment, even when the discharge pressure fluctuates small around the target pressure H8, the pump operating speed is changed after the change in the discharge pressure is sufficiently determined. This makes it possible to prevent chattering variable speed operation of the pump (increasing and decelerating changes in the speed range corresponding to the minimum resolution of the control system), and to reduce the vibration and noise associated with the variable speed of the rotating system. It can continue to decrease.

In the above explanation, an embodiment that performs unit number control and variable speed control has been described, but the present invention can also be implemented in a liquid supply device configured to perform both unit number control operation and variable speed control operation. I can do it.

In this case, it is determined that the discharge pressure does not fall within the target pressure range even though the rotation speed of the motor that is already in operation has reached the predetermined upper and lower limit rotation speeds of the motor. , pump whitening, or platform control.

In addition, in the embodiment, the target pressure was set using the switches DEI and DB2 in the embodiment shown in FIG. You can also set values.

In addition, in the embodiments already explained, the explanation was limited to the liquid supply device, but the present invention can also be used to control the operation of a blower. The present invention provides a pump, a drive device for driving the pump, a pressure sensor connected to the discharge side of the pump, a memory device for setting a target discharge pressure of the pump, and a target pressure and a pressure sensor connected to the discharge side of the pump. Direction determining means compares the measured pressures of the sensors and determines whether the pump has insufficient or excessive liquid supply capacity; The present invention provides a liquid supply device comprising a control device that outputs a command signal to increase or decrease liquid capacity.1 According to the present invention, changes in the amount of water demanded can be reliably detected and stable pump control operation can be continued. .

[Brief explanation of the drawing]

Figure 1 is a block diagram showing the configuration of a conventional liquid supply device;
3 is a block diagram showing the configuration of one embodiment of the present invention, FIG. 4 is an operating characteristic diagram of the first embodiment, and FIG. 5 is a diagram of the operating characteristics of a conventional liquid supply device. 6 is a block diagram showing a part of the control circuit of the control device of the first embodiment, and FIG. 7 is a block diagram showing the main circuit of the control device of the first embodiment. 8 is a diagram showing the output signal of the pressure sensor, FIG. 9 is a flowchart explaining the basic operation of the first embodiment, and FIG. 10 is a diagram showing the same details. A flowchart for explaining the operation, FIG. 11 is a flowchart for explaining the operation of the second embodiment of the present invention, -
FIG. 12 is an operating characteristic diagram of the third embodiment of the present invention, and FIG.
14 is a block diagram showing the configuration of another embodiment of the present invention, FIG. 15 is an operating characteristic diagram of another embodiment, and FIG. 16 is a flowchart for explaining the operation of the third embodiment. is a block diagram showing a control device of another embodiment, FIG. 17 is a flowchart for explaining the operation of the other embodiment,
FIG. 18 is an operating characteristic diagram of still another embodiment of the present invention, and FIG. 19 is a flowchart for explaining the operation of still another embodiment. P* PI *P! e"fi*P4...'Pump, 1M...Driver, ps...Pressure sensor, M
...Storage device, DP...Liquid supply pipe, HO*HI, H
4...Target pressure, L...Resistance curve, Sl, S2...
・Increase/decrease command signal 57 Nose 1 Figure 2 Korin 3 Figure 6 Figure 7 Figure Sin 8 Figure 12 Figure a→

Claims (1)

[Claims] 1. A pump, a driving device that drives the pump, a pressure sensor connected to the discharge side of the pump, a storage device that sets a target discharge pressure of the pump, and this storage device. Compare the target pressure of and the measured pressure of the pressure sensor,
A direction determining means for determining whether the two have a predetermined relationship, and based on the determination result of this direction determining means,
A liquid supply device comprising: a control device that outputs a command signal to increase/decrease the liquid supply capacity of the pump to the drive device. 2. In claim 1, there is provided a power supply provided with the direction determining means for determining that the target pressure and the measured pressure have a predetermined relationship exceeding a value several times the resolution of the control device. liquid equipment. 3. In claim 1, the pump 4 includes a pump group consisting of a plurality of pumps, a drive device for driving the pump group, a pressure sensor connected to the discharge side of the pump group, and a pressure sensor connected to the discharge side of the pump group; A storage device for setting the whitening command pressure and mounting table command pressure of the pump group is used, and the whitening command pressure and mounting table command pressure of this storage device are compared with the measured pressure of the pressure sensor, and the two are in a predetermined relationship. and a control device that outputs a command signal to increase or decrease the liquid supply force of the pump group to the drive device based on the determination result of the direction determination device. 5. In claim 4, the determination determines that the whitening command pressure or mounting table command pressure and the measured pressure have reached a predetermined relationship exceeding a value several times the resolution of the control device. Liquid supply device equipped with means. 6. The liquid supply device according to claim 4, which is provided with the storage device that sets the whitening command pressure along the resistance curve of the water supply pipe system according to the number of operating pumps in the group.