JPH08326109A - Water supply direct-connection water service system - Google Patents

Abstract

PURPOSE: To realize stabel supply by decreasing the start frequency of a pump in a water line direct connection water service system. CONSTITUTION: A second pressure sensor 7 provided at a suction pipe 2 connected to a water main 1 and a first pressure sensor 18 provided at a water feed pipe 20 are compared with each other, and by means of a controller 21, a pump is stopped in a case in which the origin pressure of the water main 1 has become, at discharge side required pressure, for more than a fixed time higher than a value that considers resistance between both pressure sensors 7, 18, and the pump is started again in a case in which the pressure of the water main 1 has become lower than a target pressure. After this condition has been realized, whether or not a small water amount use state exists is decided, and the pump is stooped in the case of a small water amount state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water supply system directly connected to a water supply system for automatically supplying water from a water distribution pipe to an end water tap.

[0002]

2. Description of the Related Art For example, since the water in a water pipe is under original pressure (hydrostatic pressure), it is possible to supply water to the end water tap of a two-story building by this original pressure. However, when it comes to middle- and high-rise buildings with three or more stories,
There is a case where it is not possible to supply water to the terminal hydrant due to the insufficient pressure alone. Therefore, the water from the water distribution pipe is once put in a water receiving tank, and from this water receiving tank, the water is supplied from the elevated water tank provided on the roof of the building to the terminal water tap on each floor by natural flow. Alternatively, the water once put in the water receiving tank was directly supplied to the terminal water tap by a pressure pump.
However, recently, in order to use the pressure of the water main and eliminate an unsanitary water receiving tank, studies have begun to directly connect a water supply device to the main to supply water. Japanese Patent Application No. 3-30560 (Japanese Patent Application Laid-Open No. 4-330127)
There is.

[0003]

However, the prior art has the following problems. (1) Operate the pump by determining whether the source pressure of the water distribution pipe upstream of the electric pump is in the range from the minimum pressure to a predetermined pressure or less and whether the discharge pressure downstream of the pump is equal to a constant pressure. Therefore, in the actual control, there is a dead zone at the predetermined pressure, the discharge pressure is equal to the predetermined pressure even when the load usage amount is considerably large, and when the load water usage amount is large, the pump is started immediately after stopping. However, after that, starting and stopping are repeated and the frequency of starting the pump increases, and the motor and its driving means wear and deteriorate. Further, the drive means is an inverter or the like, and the response is not good as compared with a general direct insertion start method, so that the water supply pressure temporarily decreases at the time of start.

(2) Pressure sensors for detecting the source pressure and the discharge pressure are provided respectively. Between them, a pump, valves, etc., especially on the suction side for preventing pollution due to backflow from the load side in a direct connection water supply system. A check valve is supposed to be installed, and the resistance loss of the check valve is large (for example, some pressure reducing types have a resistance loss of about 10 m). Not being considered,
It is also a cause of a momentary drop in the water supply pressure at the start of (1).
Therefore, in the present invention, when the source pressure of the water distribution pipe is sufficient, this source pressure energy is utilized, and when the pump is stopped, the usage state on the load side and the resistance loss described above are taken into consideration, and It is an object of the present invention to provide a water supply system directly connected to the water supply which does not need to be installed, reduces the maintenance cost of the water supply system directly connected to the water supply, and has no problem in health and safety.

[0005]

In order to achieve such an object, according to the present invention, a water supply pipe for supplying water from a water distribution pipe to an end water tap and an intermediate water supply pipe are provided. At least one electric pump that discharges water to the terminal water tap, a source pressure sensor that is arranged in a water supply pipe upstream of the electric pump and detects a source pressure of a water source, and a water supply pipe downstream of the electric pump. Is installed in the load side, an excessive water amount detecting means for detecting the usage state of the excessive water amount on the load side, a discharge pressure sensor for detecting the discharge pressure, and a detected original pressure within the range from the minimum pressure to the predetermined pressure and the following conditions. When the above condition is satisfied, a drive means for designating and supplying variable electric power to the electric pump based on a signal from a control means for outputting a signal for operating the electric pump is provided. is there.

(1) When the source pressure sensor detects a value obtained by adding resistance loss according to the amount of water used between the two to the detection value of the discharge pressure sensor, a pump stop signal is issued. (2) When the detected value of the source pressure sensor is P ₁ , the detected value of the discharge sensor is P ₂ , and the resistance loss according to the amount of water used between both sensors is Pf, the condition of P ₁ -P ₂ ≧ Pf is satisfied. Then, the pump stop signal is issued. (3) In addition to these stop conditions (1) or (2), the condition that the excessive water amount detecting means detects the excessive water amount is added. (4) When the discharge pressure becomes equal to the original pressure and the excessive water amount detecting means detects the excessive water amount, a stop signal is issued. That is, the pump is started when both the source pressure starting condition and the discharge pressure starting condition are satisfied, and the pump is stopped when both the source pressure stop condition and the discharge pressure stop condition are satisfied.

[0007]

[Action]

1) The control means detects the original pressure and determines whether the original pressure is equal to or more than the sum of the discharge side predetermined pressure and the resistance loss of each water supply device from the source pressure sensor to the discharge pressure sensor. If is higher than that, it issues a signal to stop the pump. 2) The control means detects the source pressure and the discharge pressure, and determines whether the pressure difference between the source pressure and the discharge pressure is equal to or more than the resistance loss of each water supply device between them.
If the judged result is more than that, a signal for stopping the pump is issued. 3) Further, after the stop conditions by the source pressure in 1) and 2) above are satisfied, the operation of the flow rate switch is determined, and a stop signal is issued when the amount of water used is small. 4) When the source pressure sensor detects the water supply limiting pressure, it outputs to the inverter a signal that locks at the current pump operating speed until the source pressure exceeds this.

[0008]

Embodiments of the present invention will be described below with reference to FIGS. A first embodiment of the present invention will be described with reference to FIGS. Here, FIG. 1 is an overall configuration diagram showing an embodiment of a direct water supply system for water supply according to the present invention, FIG. 2 is a graph showing each set pressure of inflow pressure (source pressure), and FIG. FIG. 4 is a graph showing an example of a constant control method, FIG. 4 is a graph showing an example of a constant control method of pump end pressure, and FIG. 5 is a graph showing resistance loss of each instrument from the position of the original pressure sensor to the position of the discharge pressure sensor. The graph shown in FIG. 6 is a control circuit diagram of the water supply system directly connected to the water supply according to the present invention, and FIGS. 7 and 8 are flowcharts showing the operation of the embodiment of the present invention. In this embodiment, a plurality of flow paths branched from a suction pipe 2 connected to a water mains 1, and pumps 10 and 11 provided in each of the flow paths and upstream and downstream sides of the pumps 10 and 11 are provided. The sluice valves 8, 9, 16, which are respectively installed on this side in this flow path.
17, and a water supply pipe 20 connected downstream of the sluice valves 16 and 17 on the downstream side so as to combine a plurality of flow paths into one
A first pressure sensor 18 and a pressure tank 19 provided on the water supply pipe 20, a second pressure sensor 7 provided on the suction pipe 2, and a control device for controlling the plurality of pumps 10 and 11 are provided. . Further, the suction pipe 2 and the water supply pipe 20 are provided with a bypass pipe 102 in which a check valve 101 is arranged in the middle thereof.

The control device 21 stops the pump when the source pressure of the water pipe becomes higher than the pressure required on the discharge side for a certain time or more than the value considering the resistance between the pressure sensors, and the water main It is configured to restart the pump when the pressure of 1 drops below the target pressure.
Furthermore, in order to prevent a drop in the water supply pressure on the load side, it is determined whether or not a small amount of water is being used after the above conditions are met, and the pump is stopped in the case of a small amount of water. Further, as shown in FIG. 6, the control device 21 includes inverters 26 and 27 that control the speeds of the pumps 10 and 11, and when the pressure of the main water supply building falls below a predetermined water supply restriction pressure, this pressure is exceeded. It locks at the current speed until it returns. The details will be described below.

FIG. 1 shows the structure of the water supply system of this embodiment.
6 is a check valve (prevention of backflow) for preventing pollution, 7 is a second pressure sensor for detecting the main pressure on the suction side of the pump,
Similarly, 18 is a first pressure sensor for detecting the pressure on the water pipe side, 8, 9, 16 and 17 are gate valves, respectively.
14 and 15 are check valves, 8 and 9 are electric motors 12,
The pump 102 driven by 13 is a bypass pipe provided with a check valve 101 in the middle thereof, and as described above, when the water main can be supplied only with sufficiently high source pressure, the pump is stopped and this bypass is bypassed. Supply water through a pipe. Reference numeral 19 is a pressure tank having an air trap inside, and numerals 23 and 24 are flow rate switches for detecting a small water usage state.

FIG. 6 is a control device 2 of the water supply device of this embodiment.
1 shows the details, PW is a power source, 23 is a circuit breaker for wiring, 2
Reference numerals 4 and 25 are coils of an electromagnetic contactor for driving and driving the electric motors 12 and 13, respectively, and 24a and 25a are main circuit contacts thereof. Further, 26 and 27 are the electric motor 1
An inverter for driving 2 and 13
Reference numerals 5 and 46 are consoles (key input devices) for performing various settings of the inverter (for example, setting of the lower limit value of the operating speed range of the inverter). N1 and N2 are signals for instructing the speed of the inverter, which will be described later.
Similarly to a and 29a, it is an operation command signal and is operated when this is ON. Reference numeral 30 is a switch, and by closing this switch, the stabilizing power supply unit 31 is activated, control power is supplied to the power supply terminal 33, and preparation for automatic operation is completed.

Reference numerals 34 and 35 respectively denote an interface composed of a D / A converter for issuing a speed command to the above-mentioned inverter, 36 a CPU of a microcomputer, 37 a memory composed of a RAM and a ROM, 38, 39, 40 and 41 are input / output ports.
Reference numerals 42 and 43 are switches for setting pressure and speed data.

FIG. 2 shows an example of the set data. The set values of the inflow side pressure a (minimum pressure: pump idling protection stop pressure), b (water supply limit pressure), c (inflow pressure high stop pressure).
Etc. are set. The inflow pressure high stop pressure c is a value obtained by adding resistance between the pressure sensors to H0 when using FIG. 3, and when using FIG. 4, H4 is used instead of H0 described above.
And Further, as will be described later in detail, the pressures H1 (point of water amount 0), H4 (points of water amount Q), which are target values when performing the pressure control shown in FIG. Values such as b and c are set with the switch 42, data of operating speeds ND and NA are also set with the switch 43, and the data are read into the memory via the PIOs 39 and 40, respectively (R
Store it in AM). Naturally, the R of this memory M
Needless to say, programs such as operation control procedures are written in the OM as described later. Note that ND is an initial value and is set in advance.

Reference numeral 44 is an interface for A / D converting the pressure signals of the first and second pressure sensors 7 and 18 to read them, and similarly to the memory (RAM) via the input port 41. Store it. The control device CTL is configured as described above.

FIG. 3 shows an operating characteristic diagram in the case of a general constant discharge pressure control, in which the vertical axis is the total head H and the horizontal axis is the water amount Q.
Take and show. The curves A, B, C and D have continuous operating speeds, but the speeds are changed to NA (maximum speed) NB and N, respectively.
It is the pump Q-H performance when it is assumed to be C and ND (minimum speed), and H0 is the target discharge pressure at this time.

Similarly, FIG. 4 is a diagram showing an operating characteristic in the case of a general constant end pressure control system, which is designated by the same reference numeral as FIG. In the figure, a curve E is a resistance loss curve of a water pipe or the like. In this method, the amount of water used is Q, Q, Q, Q
If it changes from C to Q, the operating speed of the inverter is N
A, NB, NC, ND changes and the operating point of the pump is curve E
The top changes to a, b, h, and d. Further, in FIGS. 3 and 4, Qs indicates the operating flow rate of the small water amount detection sensors 23 and 24. If the flow rate is small, Qs, for example, closes the contact point, thereby opening the contact point with a slightly larger water flow rate.

Normally, constant discharge pressure control is often used for water supply in apartments, condominiums, etc., where pipe resistance is small relative to the actual pump head. When the water pipe has a long pipe resistance with respect to the actual head, long terminal pressure constant control is used. An optimum water supply system is selected from these methods, and the operation is controlled according to the operation procedure programmed in advance according to the operation characteristic diagram described above.

By the way, in FIG. 1, considering that the pump is not operated and water is supplied only by the main pressure of the water mains, it is necessary to consider the resistance loss of the check valve, the pump, the gate valve, and the piping. Needless to say. That is, when a predetermined pressure on the load side (H0 in FIG. 3, H4 in FIG. 4) is secured under the discharge side pressure sensor 18, the sensor 1 is detected at the source pressure sensor 7.
Sufficient water cannot be supplied unless a pressure equal to or higher than the above-mentioned resistance loss is added to the required pressure at 8 points. FIG. 5 shows this resistance loss, j is the resistance loss when the maximum amount of water used is Q, and similarly K is the resistance loss when the amount of water is too small Qs. As mentioned in the prior art,
If the inflow pressure high stop pressure C is set equal to H0 or H4, the inflow side pressure becomes C, and when the pump stops, the pressure at the discharge side pressure sensor 18 falls below this C by the amount of this resistance, and the pump immediately operates. Start and inching. Alternatively, the water pressure at the high-load side faucet temporarily drops.

Therefore, as shown in the X frame in FIG. 7, it is judged whether the stop condition is satisfied when the original pressure becomes equal to or higher than C (value obtained by adding the resistance loss Pf to the discharge side predetermined pressure H0 or H4). It is designed to be stopped. More specifically, in step S700, the CPU for driving is initialized, and in step S701, permission to jump to the timer interrupt process shown in FIG. 8 is granted. Step S8
In 01, the original pressure is detected by the pressure sensor 7, and the result is stored in the memory S
Store in PDATA. Similarly, in step S802, the pump discharge pressure is detected by the pressure sensor 18, and the memory D
Store in PDATA. Further, the states of the flow rate switches 23 and 24 are checked in step S803, the results are stored in the memory, the fault state of the pump or the like is detected and stored in the memory in step S804, and the switches 42 and 43 are set in step S805. Read data and store in memory respectively. After this, in step S806, the interrupt processing is returned to step S702. In step S702, it is determined whether the starting condition is established.

For example, in FIG. 3 and FIG. 4, when the water supply pressure (pump discharge pressure) falls below H3, the pump is started in step S703, and a signal indicating that the inverter frequency is ND is output. In the next step S704, the original pressure (memory SP
(Stored in DATA) is greater than or equal to b shown in FIG. 2, and if it is greater than or equal to b, the process jumps to step S709, and if not, the process proceeds to step S705, which will be described in detail later. In step S709, H4 and H1 are compared to determine whether the discharge pressure constant control method is the end pressure constant control method. If H4 = H1 = H0 (see FIG. 3 and FIG. 4), it means that the discharge pressure is constant and the step S714.
If not, the process proceeds to step S710 to execute each process (step S710, step S710).
714).

In step S715, the above-mentioned resistance loss Pf = j (see FIG. 5) by the constant discharge pressure control and Pf = (N) in step S711 with the constant end pressure control are shown in FIG.
A resistance loss based on the operating speed N is given as shown in FIG. 7, and in step S712, the source pressure (SPDATA) is C (H0 + j in the case of the constant discharge pressure control method, and a target value in the case of the constant end pressure control method). F (N) for pressure on E
It is confirmed whether it is higher than (the value obtained by adding (Pf = f (N))).
Proceeding to step 716, in step S713, it is confirmed whether the state in which the original pressure is higher than C has continued for Δt time. If it continues, sufficient water can be supplied only by the original pressure. Run. Step S712
If it is determined in 713 that water cannot be supplied at the original pressure, normal control by the discharge side after step S716 is performed.

Next, another embodiment in which the pump is stopped when the pressure difference between the pressure sensors 7 and 18 exceeds the resistance loss will be described with reference to FIG. FIG. 8 shows a modification of the X part shown in FIG. 7, and in step S900, the original pressure (memory SPDAT
(Stored in A) and discharge pressure (stored in the memory DPDATA), DELTAP is determined, and it is determined in the next step S901 whether or not the resistance loss Pf is greater than or equal to the above. As in step S
At 902, it is determined whether or not this state continues for Δt time. If it continues, it means that water can be sufficiently supplied at the original pressure. In step S903, the pump is stopped and water is supplied at the original pressure. Other than this, the description is omitted because it is the same as the description of FIG. 7.

By doing so, it is possible to solve the problems described in the prior art, such as the inching of the pump and the temporary decrease of the water pressure. An embodiment in which these problems are solved and the starting frequency is further improved will be described with reference to FIG. In the figure, after the source pressure shown in FIG. 7 or FIG. 8 satisfies the stop condition, step S103 is inserted under these conditions in order to stop the pump when the water usage condition is small. Is. That is, steps S100 to S102 use the example of FIG. 9, and after the stop condition at the original pressure is satisfied, it is determined in step S103 whether the flow rate switch is operating, and the usage amount is small (usually 10 to 20 l). / Mm or less) If it is operating, the pump is stopped in the next step S104.

In this way, the pump can be stopped only when the water is supplied by the original pressure and when there is almost no water used on the load side. Therefore, the pump start frequency can be further reduced. . Furthermore, as described in the prior art (see FIG.
1) Pump stop pressure C due to original pressure is C = J0C = H
In the case of selecting 4) as well, as shown in FIG. 10, the conventional problems described above can be solved by stopping the pump and supplying water at the original pressure only when the amount of water used is extremely small.

By the way, in this water supply system directly connected to the water pipe, the water supply system directly connected is preferentially used even when the water supply is restricted, as compared with other water supply systems, and there is a concern that it is unfair. is there. An example of a countermeasure against this will be described with reference to FIG. That is, the source pressure in step S705 in FIG.
If it is determined to be b or less by the following determination, the next step S
Proceed to 705 (see FIG. 2). In step S705, the speed command signal N1 or N2 of the inverter (26 or 27) is output so as to lock the current pump operating speed until the original pressure exceeds b. Further, after step S706, it is determined whether the source pressure is equal to or lower than the minimum pressure a shown in FIG. 2, and if so, the pump is stopped for idling protection. In this way, the water supply limiting pressure b is determined in advance, and when the source pressure falls below this, the operating speed of the pump is locked at the current speed, so the water supply is limited and the unfair feeling is eliminated.

[0026]

As described above, according to the present invention, when the source pressure applied to the water pipe exceeds the predetermined pressure on the discharge side and the resistance loss from the source pressure sensor to the discharge pressure sensor. Or, with this condition and the condition that the amount of water used is small, it is judged that the source pressure water supply is possible, so the energy of the source pressure can be used, not only energy saving but also the starting frequency It is low, and it is possible to prevent a temporary decrease in water supply pressure, and stable water supply is possible. In addition, since it is not necessary to install a water tank, safety and hygiene management and high labor costs for this are unnecessary, and therefore maintenance costs for this direct water supply system can be reduced and there is a problem in terms of health and safety. There is no.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of a water supply system directly connected to a water supply according to the present invention.

FIG. 2 is a graph showing each set pressure of inflow pressure (original pressure).

FIG. 3 is a graph showing an example of a control method in which the pump discharge pressure is constant.

FIG. 4 is a graph showing an example of a control method in which the pump end pressure is constant.

FIG. 5 is a graph showing resistance loss of each device from the position of the original pressure sensor to the position of the discharge pressure sensor.

FIG. 6 is a control circuit diagram of a water supply system directly connected to a water supply according to the present invention.

FIG. 7 is a flowchart showing the operation of each of the above embodiments.

FIG. 8 is a flowchart showing the operation of each of the above embodiments.

FIG. 9 is a flowchart showing the operation of each of the above embodiments.

FIG. 10 is a flowchart showing the operation of each of the above embodiments.

FIG. 11 is a graph showing each set pressure of the inflow pressure (original pressure).

[Explanation of symbols]

 1 Water mains 6,14,15 Check valve 7 Source pressure sensor in suction pipe 18 Discharge pressure sensor in suction pipe 2, Pump 11 Pressure tank 21 Control device 26,27 Inverter

Claims (7)

[Claims] 1. A water supply pipe for supplying water from a water supply pipe to an end water tap, at least one electric pump interposed in the middle of the water supply pipe to discharge water to the end water tap, and an upstream of the electric pump. Side pressure sensor for detecting the source pressure of the water source, the discharge pressure sensor for detecting the discharge pressure, which is disposed on the downstream side of the electric pump, and the detected source pressure. When the required pressure on the side and the resistance between the two pressure sensors have been exceeded, the pump is stopped and water is directly supplied at the water pipe pressure, and when the detected discharge pressure falls below the specified starting pressure. A water supply system directly connected to a water supply system, comprising: a control means for outputting a signal for starting the operation; and a drive means for designating and supplying variable electric power to the electric pump based on a signal from the control means. 2. The pressure detected by the source pressure detection sensor is set to SPD.
ATA, the pressure detected by the discharge pressure sensor is DPDAT
A, and a resistance loss between them is Pf, and a control means is provided for outputting a signal for stopping the pump when the pressure relationship between them becomes SPDATA-DPDATA ≧ Pf. Directly connected water supply system. 3. The water supply system directly connected to a water supply system according to claim 1, wherein the resistance loss detected by both pressure sensors is a value at an operating speed corresponding to a predetermined water amount and a predetermined pressure. 4. A water supply pipe for supplying water from a water distribution pipe to an end water tap, at least one electric pump interposed in the middle of the water supply pipe to discharge water to the end water tap, and an upstream of the electric pump. Source pressure sensor installed in the side water supply pipe to detect the source pressure of the water source, an underwater amount detection means installed in the water supply pipe downstream from the electric pump to detect the underwater amount, and a discharge for detecting the discharge pressure. When the pressure sensor and the detected original pressure are equal to or greater than the sum of the required pressure on the discharge side and the predetermined resistance between the pressure sensors, and the excessive water amount detecting means detects the excessive water amount state, the pump is stopped. , Control means for outputting a signal for starting when the distribution pipe pressure is directly supplied and the detected discharge pressure falls below a predetermined starting pressure, and variable power based on the signal from this control means Specify as an electric pump A water supply system directly connected to a water supply, comprising a drive means for supplying the water. 5. The pressure detected by the source pressure detection sensor is set to SPD.
ATA, the pressure detected by the discharge pressure detection sensor is DPDAT
A, when the resistance loss between them is Pf, the pressure relationship between them becomes SPDATA-DPDATA ≧ Pf, and the control means for outputting a signal to stop the pump when the underwater amount detection means detects the underwater amount The water supply system directly connected to the water supply system according to claim 4, wherein the water supply system is provided. 6. A water supply pipe for supplying water from a water supply pipe to an end water supply tap, at least one electric pump interposed in the middle of the water supply pipe to discharge water to the end water supply tap, and an upstream of the electric pump Side pressure sensor for detecting the source pressure of the water source, an excessive pressure detecting means for detecting an excessive amount of water and a discharge pressure for detecting an excessive amount of water. The discharge pressure sensor and the detected original pressure is within a range from a minimum pressure or more to a predetermined pressure or less and a discharge pressure is less than or equal to a constant pressure, and it is determined whether the excessive water amount detecting means detects an excessive water amount, and the electric pump is operated. A water supply system directly connected to a water supply, comprising: a control unit that outputs a signal for operating the drive unit; and a drive unit that specifies and supplies variable electric power to the electric pump based on a signal from the control unit. 7. A water supply pipe for supplying water from a water distribution pipe to an end water tap, at least one electric pump interposed in the water supply pipe for discharging water to the end water tap, and an upstream of the electric pump. Source pressure sensor for detecting the source pressure of the water source, which is arranged in the side water supply pipe, a discharge pressure sensor which is arranged in the water supply pipe downstream of the electric pump for detecting the discharge pressure, and controls the plurality of pumps. Which includes an inverter for controlling the speed of the pump, and when the source pressure of the water source has dropped to a predetermined water supply limit pressure, the current pressure until the pressure exceeds this is restored. A water supply system directly connected to the water supply, characterized by being locked at the speed of.