JPH0156280B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pressure tank type water supply device that allows a pump to be operated properly.

Conventionally, in a pressure tank type water supply system having a relatively small pressure tank, as a means to suppress the frequency of starting the pump, a pressure detection means and a timing means have been combined, and if the pressure detection means does not start the pump, A pressure tank type water supply device has been proposed that continues operation for at least the time measured by a timer (set time) after detecting a pressure that cannot be stopped or a pressure that can be stopped.

An example of such a configuration is shown in Figures 1 and 2.
This will be explained with reference to FIG. FIG. 1 is a system diagram of a pump, in which numeral 1 indicates a pump, 2 a check valve, 3 and 4 gate valves, and 5 a pressure detection means provided in a pressure tank 6. FIG. 2 is a diagram showing the operating characteristics of the pump, with the water amount Q plotted on the horizontal axis and the pressure H plotted on the vertical axis. Figure 3 shows the control means for operating the pump;
is the pump motor switch, and Ma is its energized closing contact. The contact PS of the pressure detection means 5 is the second
It is set to close at the first pressure P1 and open at the second pressure P2 shown in the operating characteristic diagram in the figure.

In the pump 1, the pressure inside the pressure tank 6 is the first pressure.
It starts when the voltage drops to P1 and the contact PS closes. Then, water flows from pump 1 to check valve 2,
It passes through the gate valve 3, pressure tank 6 and gate valve 4 and is sent to the end faucet.

Simultaneously with the start, the timer T is energized, and the pump 1 continues to operate until both the pressure detector 5 and the timer T are cut off.

In this way, when the contact PS of the pressure detection means 5 closes, the timer T is activated and the pump 1 is operated for a certain period of time or more. According to this device, the pressure in the pressure tank stops from the starting pressure. When the pressure is restored to a good level in a short period of time, the pump must continue to operate for a considerable period of time, resulting in a problem of high power consumption. Therefore, the present invention provides a pressure tank type water supply device that can shorten the unnecessary operating time of the pump and takes power-saving measures.

That is, the present invention includes a pump, a pressure tank connected to the discharge side of the pump, and a detection system for detecting a first pressure in the pressure tank at which the pump should be started and a second pressure at which the pump may be stopped. In a water supply device equipped with a means, when time measurement has ended, time measurement is started based on a signal that detects the second pressure from the detection means, and when time measurement is in progress, the scheduled time measurement is started regardless of the output of the detection means. A timer that continues to measure time and ends the timer after a predetermined period of time; and a timer that continues to measure time and ends the timer after a predetermined period of time; The control means operates the pump until the end of the time measurement and stops the operation of the pump based on the detection of the second pressure when the detection means detects the first pressure after the end of time measurement.

Further, even when two or more pumps are operated in combination, the timing means is configured to act on both the preceding pump and the following pump.

Now, let us explain the first embodiment in Figs. 1, 2, and 4.
This will be explained using FIG. FIG. 4 shows the control means for the water supply device, and is an improved version of FIG. R1 and R2 are relays, R1a is relay R
1 shows the closed contact when energized. R2a is relay R2
It is an open contact when energized, but it is an off-delay contact that opens several tens of milliseconds after the energization of relay R2 is released. Mb is the energized open contact of the switch M. Components denoted by the same reference numerals as those shown in FIG. 3 are the same as those shown in FIG. 3, so their explanation will be omitted.

FIG. 5 is a time chart for explaining the operation of the control means shown in FIG. The explanation will now begin from the point in time shown at t1 in FIG. 5, when the timer T has already finished measuring time, the contact Tb is open, and the pump 1 is stopped. At this time, contact PS is open, so switch M is in a released state. As a result, the contact Mb is closed, so the timing means T is shown in Figure 5.
It is in an energized state as shown by T'. However, the timing operation has already ended, as indicated by T''.Relays R1 and R2 are released, and therefore contacts R1a and R2a are open.

When the water faucet at the end is opened in this state, the pressure inside the pressure tank 6 drops to the starting pressure P1, the contact PS of the pressure detection means 5 closes, and the switch M is energized.
Pump 1 starts.

When switch M is energized, its contacts
Ma closes and Mb opens. In this state, contact Tb is closed. The above is the time t2 in FIG.

As the amount of water used decreases, the pressure in the pressure tank 6 increases, and when it reaches the stop pressure P2, the contact PS of the pressure detection means opens, and the switch M is released.
Pump 1 stops. Following the release of switch M of pump 1, contact Mb closes and timing means T is energized, and since contact Tb is already closed, relay R1
becomes activated. Therefore, the timer T starts measuring a preset time. At the same time, contacts R1a and R2
a is closed, and relay R2 becomes energized. The above is the time point t3 in FIG.

Next, the amount of water used increases again, and the pressure in the pressure tank 6 decreases to the starting pressure P1.
The contact PS of the pressure detection means is closed, the switch M of the pump 1 is energized, and the pump 1 is started. Then, the contact Ma is closed by the energization of the switch M of the pump 1. Contact Mb is open, but since the timing means T is still measuring time, contact Tb is closed. As a result, relays R1 and R2 remain energized, and contact R
1a and R2a are closed. Therefore, the contact Ma and the contact R1a of the relay R1 form a holding circuit A in parallel to the contact PS of the pressure detection means.
The above is the time point t4.

At this time, if the amount of water used suddenly decreases,
Contact PS of pressure detection means 5 due to sudden increase
Even if the pump 1 opens or closes, the holding circuit A causes the pump 1 to continue operating until the contact PS of the pressure detection means opens and the set time of the timer T elapses.

If the contact PS of the pressure detection means 5 opens first at time t5 and the operation is continued by the timer T, when the timer T finishes measuring time at time t6, its time limit contact Tb opens and the relay R1 is released. be done.
Therefore, contact R1a of relay R1 opens, switch M is released, and pump 1 is stopped.

By the way, when the contact Tb opens, the switch M is released and the contact Mb is closed, and as a result, the contact R
2a opens, but before contact Mb closes, contact R2
If a opens, the timing means T will start timing when the contact Mb closes, but since the contact R2a uses an off-delay contact so that it opens after the contact Mb closes, the timing At t6, the clock means is not reset.

The operation at time t7 is the same as the operation at time t2, and the operation at time t8 is the same as the operation at time t3. In other words, as described above, since the timer T measures the scheduled time from when the pump is stopped, the pump 1 continues to operate even after reaching the second pressure P2, and the timer T measures the scheduled time after the contact PS of the pressure detection means is disconnected. This is the time until the means T completes the timing operation, that is, only the time indicated by the shaded area shown in FIG.

Then, when the detection means detects the first pressure P1 after the time measurement by the timer T ends, the pump 1 is stopped only by a command from the contact PS of the pressure detection means.

From the above, the set time of the timer T is set to a time sufficient to ensure the minimum required starting frequency of the pump in order to save operating power.

Next, a second embodiment, which is a further application of the first embodiment, will be described using FIGS. 6, 7, and 8. In this example, the amount of water used is divided and supplied by two pumps (or more than one pump is OK), and when the amount of water used is small, the pumps are operated alternately, and when the amount of water used is increased, they are operated in parallel. In this case, the above-mentioned timing means works on both the leading side and the following side, so that the control device can be configured economically and inexpensively, and the starting frequency can be reduced even if the pressure tank capacity is small. This is what made it possible.

Figure 6 is a system diagram, where symbols with the same reference numerals as in Figure 1 indicate the same parts, 11 is the No. 1 pump, 12 is the 2nd pump.
51 is a pressure detection means for detecting a first pressure at which only one pump should be operated and a second pressure at which one pump is to be stopped; 52 is a third pressure at which the number of pumps in operation should be increased. and pressure detection means for detecting a fourth pressure at which the number of pumps that are already in operation should be reduced. FIG. 7 is a diagram showing the operating characteristics of the pump of this embodiment, where the same symbols as in FIG. 2 indicate the same pressure and water amount. Curve A represents the Q-H performance when only one pump is operated.
indicates the combined Q-H performance when the No. 1 pump 11 and the No. 2 pump 12 are operated in parallel, P3 indicates the starting pressure of the follower pump, that is, the third pressure, and P4 indicates the stop pressure, or the fourth pressure, of the follower pump. Pressure detection means 5
1 is the first pressure P1 which is the starting pressure of the preceding pump
P2, which is the second pressure that is the stopping pressure.
The pressure detecting means 52 opens at a third pressure P3, which is a starting pressure of the follower pump lower than the first pressure P1, and closes at a fourth pressure P3, which is a stopping pressure lower than the second pressure P2. It is set to open at a pressure P4 of . FIG. 8 shows a control means for operating the pump of this embodiment,
Symbols shown with the same reference numerals as in Fig. 4 indicate the same parts,
M1 and M2 are No. 1 pump 11 and No. 2 pump 1
In the operation switches No. 2, M1a and M2a indicate closed contacts when the switches M1 and M2 are energized, respectively, and M1b and M2b indicate open contacts when the switches M1 and M2 are energized, respectively.
Rx is an alternating switching relay that switches its contact Rxc from the a side to the b side and then from the b side to the a side each time the ratchet relay is energized. T1 is a timing means, T1a' is its instantaneous closing contact, and T1a
is a time-limited contact that closes after a certain period of time after being energized. And the energizing contacts M1a of the operation switches M1 and M2,
Connect M2a in parallel, contact R1 of relay R1
The holding circuit A connected in series with the pressure detecting means 51 is connected in parallel with the contact PS1 of the pressure detection means 51, and similarly the holding circuit A is connected in series with the contact PS1 of the pressure detection means 51, and the contact R1a of the relay R1 and the operating switches M1a, M2a are connected in parallel.
A holding circuit B, in which three of these are connected in series, is connected in parallel to the contact PS2 of the pressure detecting means 52 to constitute a control means.

To explain the operation of the system configured in this way, the independent operation of the No. 1 pump 11 or the No. 2 pump 12 is the same as that described above. However, during independent operation, whether it is No. 1 pump 11 or No. 2 pump 12, if the pump stops, during parallel operation, if both pumps stop, the ratchet relay will be activated.
Rx is energized and its contact Rxc is moved to the a side (or b side)
Since the switch is switched from the side to the b side (or to the a side), the operation is alternate.

It is now assumed that contacts c and b of the ratchet relay Rx are closed, the pressure in the pressure tank 6 is high, and both the pumps 11 and 12 are stopped. Further, it is assumed that the timer T has already timed up and its time limit contact Tb is open. When the water faucet at the end is opened in this state, the pressure inside the pressure tank 6 drops to the starting pressure P1, the contact PS1 of the pressure detection means 51 closes, and the switch M2 is energized.
Pump 12 is started.

As the amount of water used decreases, the pressure in the pressure tank 6 increases, and when it reaches the stop pressure P2, the contact PS1 of the pressure detection means opens, the switch M2 is released, and the pump 12 is stopped.

Then, since contact M1b has already been closed and contact M2b will newly close, the ratchet relay will be closed.
Rx becomes energized and its contact switches from b to a. Further, when the switch M2 of the pump 12 is released, the contact M2b is closed, thereby energizing the timer T and the relay R1. Therefore, the timer T starts counting time for a preset time. Next, when the amount of water used increases again and the pressure in the pressure tank 6 drops to the starting pressure P1, the contact PS1 of the pressure detection means closes, the switch M1 of the pump 11 is energized, and the pump 11 is started. Then, due to the energization of the switch M1 of the pump 11, the contact M1a
and contact R1a of relay R1 constitute a holding circuit A in parallel with contact PS1 of the pressure detection means.

Now, the pressure is further increased to the starting pressure P3 of the follow-up pump.
When the pressure decreases to 1, the contact PS2 of the pressure detecting means 52 closes, and the switch M2 of the No. 2 pump 12, which is the follow-up pump, is energized and started, resulting in parallel operation. At the same time, the timing means T1 is energized, its instantaneous contact T1a' is closed, and after a certain period of time, its time-limiting contact T1a is closed and the ratchet relay Rx is energized, and its contact T1a' is closed.
Switch Rxc from side a to side b. Furthermore, since the pump operation switch M2a is closed, a holding circuit B on the follower pump side is configured.

If this state continues, the time measurement by the timer T is completed, the time limit contact Tb is opened, and the energization of the relay R1 is also released. As the amount of water used decreases, the pressure inside the pressure tank 6 increases and the stop pressure P of the follow-up pump increases.
At step 4, the contact PS2 of the pressure detection means 52 opens, and since the ratchet relay Rx is switched, the No. 1 pump 11, which is the preceding pump, stops. Furthermore, the pressure inside the pressure tank 6 increases, and the stop pressure P2
When reaching , the contact PS1 of the pressure detection means 51 also opens,
The following pump 12 also stops.

However, if the amount of water used suddenly decreases before the set time of the timer T expires, the pressure in the pressure tank 6 increases as described above and reaches the stop pressure P4 of the follow-up pump, causing the pressure detection means 52 to rise. Although the contact PS2 opens, the holding circuit B connected in parallel with this allows operation to continue until the set time of the timer T expires.

As pressure tanks become smaller, if the amount of water used suddenly changes during parallel operation,
There is a concern that the frequency of starting the follow-up pump will increase, but as described above, the timing means T also works on the follow-up side and can keep the frequency low.

Next, a third embodiment in which pumps with different characteristics are combined will be described with reference to FIGS. 9 and 10. FIG. 9 is an operating characteristic diagram of the pump of this example. Curves C and D are the Q-H performance curves of different pumps, and curve E is the combined Q of curves C and D when they are operated in parallel. -H performance, and other than that, the 7th
It is similar to the figure. FIG. 10 shows the control means of the control device for operating the pump of this embodiment.
Symbols shown with the same reference numerals as in FIG. 8 indicate the same parts.

In this example, when the pump having the performance of curve C is operated, the discharge flow rate is small, so even if it is operated, it takes time for the pressure in the pressure tank to rise to the stop pressure, and therefore the starting frequency is can be kept to a minimum. When a pump having the performance of curve D is operated, the starting frequency becomes high, so the timing means is used only in this case to reduce the starting frequency, and this is a further application of the first and second embodiments. It is. Now, it is assumed that the No. 1 pump 11 is a pump that has the performance of curve C, and the No. 2 pump 12 is a pump that has the performance of curve D.
If the pressure in the pressure tank 6 is the preceding stop pressure P2, the contact PS1 of the pressure detection means 51 opens and the pressure reaches 1.
No. 1 pump 11 stops. Simultaneously with the stop, the ratchet relay Rx is switched, and the timing means T and relay R1 are energized, closing their contacts R1a.
When the pressure in the pressure tank 6 drops to the starting pressure P1 again, the No. 2 pump 12 starts. 2
If the amount of water used is less than the amount of water pumped by the No. 1 pump 12, the pressure in the pressure tank 6 increases and the contact PS1 of the pressure detection means 51 opens, but when the set time of the timer T expires, the holding circuit A opens. The No. 2 pump 12 continues to operate until.

Since there is no self-holding contact of the switch M1 in the self-holding circuit A, when the pump 11 is in operation alone, the pressure tank is closed even when the timing means T is not measuring time or even when it is measuring time. When the internal pressure reaches the stop pressure P2, the pump 11 stops operating.

When the pump 12 is in operation alone, it continues to operate until the timing means times up even if it reaches the stop pressure P2, but when the timer T is not measuring time, it immediately stops when it reaches the stop pressure P2. do.

Note that the operation during parallel operation is the same as that in the second embodiment, so a description thereof will be omitted.

In the above embodiments, the control means is constituted by a relay circuit, but it can also be constituted by an electronic circuit.

As is clear from the above description, according to the present invention, even if the pressure tank is relatively small, the starting frequency can be kept low by using a timing means and using a simple control means that is economically and inexpensively constructed. In addition, the pump continues to operate due to the timing device only for the time period from when the pressure detection device detects a pressure that allows the pump to stop until the set time of the timing device expires. If the pump is stopped for more than a certain period of time, the pump will stop as soon as the pressure detection means detects a pressure that allows the pump to stop, so operating power can be saved compared to conventional operating methods.

Furthermore, when multiple pumps are operated in combination, the above-mentioned timing means circuit can be made to work on both the leading side and the following side, which not only makes the control device economical, but also allows the following pumps to operate in combination. The starting frequency can be kept low.

Furthermore, when operating a combination of pumps with different characteristics, the above-mentioned timing means circuit can be set to act only on a specific pump that is expected to have a high starting frequency. Of course, the overall starting frequency can be kept low.

[Brief explanation of drawings]

Fig. 1 is a basic pump operation block diagram, Fig. 2 is a pump operating characteristic diagram, Fig. 3 is a control means diagram, Fig. 4 is a control means diagram of the first embodiment of the present invention, and Fig. 5 is a diagram of the control means of the first embodiment of the present invention. The figures are a time chart for explaining the operation of Fig. 4, Fig. 6 is an operation block diagram showing the second embodiment, Fig. 7 is an operating characteristic diagram of the pump shown in Fig. 6, and Fig. 8 is a diagram showing the operation characteristics of the pump shown in Fig. 6. FIG. 6 is a diagram of the control means of the apparatus shown in FIG. 6, FIG. 9 is a diagram of the operating characteristics of the pump used in the third embodiment of the present invention, and FIG. 10 is a diagram of the control means of the apparatus of the third embodiment. 1, 11, 12... Pump, 5, 51, 52... Pressure detection means, M, M1, M2... Switch, T... Timing means, PS, PS1, PS2... Contact of pressure detection means,
P1...first pressure, P2...second pressure, P3...third pressure, P4...fourth pressure.

Claims (1)

[Scope of Claims] 1. A pump, a pressure tank connected to the discharge side of the pump, and a first pressure in the pressure tank at which the pump should be started and a second pressure at which the pump may be stopped.
In the water supply device, the water supply device includes a detection means for detecting the second pressure when the time measurement has ended, the time measurement is started based on the signal from the detection means that detects the second pressure, and when the time measurement is in progress, the time measurement is started based on the signal from the detection means that detects the second pressure. a timer that continues scheduled timekeeping regardless of the output of the means and ends the timekeeping after a predetermined time; Even if the second pressure is detected, the pump is operated until the timing means finishes counting, and when the detection means detects the first pressure after the timing is finished, the pump is operated based on the detection of the second pressure. A pressure tank type water supply device characterized by having a control means for stopping. 2. A plurality of pumps, a pressure tank connected to the discharge side of the pump, and a first pressure in the pressure tank at which one pump should be operated and a second pressure at which one pump should be stopped. and a detection means for detecting a third pressure at which the number of operating pumps should be increased and a fourth pressure at which the number of operating pumps should be reduced when a plurality of pumps are in operation. a timekeeping means that starts timekeeping based on the fact that all the pumps have stopped; if the timekeeping is in progress, continues scheduled timekeeping regardless of the output of the detection means; and ends the timekeeping after a predetermined time; When the first pressure is detected while the timekeeping means is measuring time, even if the second pressure is subsequently detected, one pump in operation is operated until the timekeeping means finishes counting, and after the timekeeping is finished, the first pressure is detected. When the pressure is detected, the operation of one pump in operation is stopped based on the detection of the second pressure, and when the third pressure is detected while the clocking means is measuring time, even if the fourth pressure is subsequently detected. The pumps in operation are operated without reducing the number of pumps in operation until the timing means finishes timing, and when the third pressure is detected after the timing ends, the number of pumps in operation is reduced based on the detection of the fourth pressure. A pressure tank type water supply device characterized by having means.