JP2008202555A - Water supply device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shirk the danger of suspension of water supply and the burst of piping due to the generation of pressure imbalance, when a water supply amount is abruptly increased/decreased, in a water supply device equipped with a controlling function successively operated by a plurality of pumps. <P>SOLUTION: The water supply device is equipped with a pump 8, a pressure sensor 16, and an inverter 2. A control board sets a target pressure value, calculates pressure by using pressure sensor input, successively operates the pumps when the water supply amount is increased, successively stops the pumps when the water supply amount is decreased, carries out control obtaining a target pressure value, simultaneously operates two or more pumps in stead of the control successively controlling the pumps when the water supply amount is abruptly increased and the pressure is greatly lowered to the target pressure value, and stops the two or more pumps to carry out simultaneous control obtaining the target pressure value, in stead of the control successively stopping the pumps when the water supply amount is abruptly decreased and the pressure is greatly raised to the target pressure value. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a water supply device, and more particularly to an operation control switching function technology in the water supply device.

  In a water supply apparatus, there is a method of performing pressure control (constant pressure control) by changing a pump rotation speed using an inverter. When the amount of feed water increases, the inverter speed is increased to keep the target pressure value constant by the inverter. Here, when the amount of water supply increases, a method of starting the other pump when the discharge pressure value set in the control panel in advance is reached is common. In addition, when detecting the discharge pressure value, a detection timer is set to prevent chattering, which is a malfunction of the pump, and switching to the other pump is performed after a certain period of time. When the amount of water increased, there was an example in which the switch to the other pump could not be performed due to the detection timer time, and the pump discharge pressure dropped rapidly, causing a water outage accident.

  Further, when the amount of water decreases, in order to keep the target pressure value constant, the pump rotation speed is reduced and constant pressure control is performed. Here, when a plurality of pumps are operating at the same time, the self-pump is stopped when the discharge pressure value set in advance on the control panel is reached, and the pump is rotated by the other pump. Carry out speed driving. Even when switching to the other pump, in order to prevent the chattering operation of the pump, a detection timer is set, and the switching operation to the other pump is performed after a predetermined time has elapsed. Here, when the amount of water decreases rapidly, such as when the pipe is closed, the pump stop operation is not in time due to the detection timer time, and the pressure in the pipe rises, which may cause a pipe rupture accident.

As an improvement measure, it is effective to install a pressure tank according to the increase / decrease in the amount of water supply in order to cope with the pressure increase / decrease due to the increase / decrease in the amount of water supply suddenly. For the capacity of the pressure tank, it is necessary to select the tank capacity according to the maximum amount of water used. In particular, in order to cope with a large amount of water, a large-capacity pressure tank is used in a water supply device that operates plural pumps in parallel. is required.
JP-A-8-254195

  The present invention provides a water supply apparatus having a control function for sequentially operating by a plurality of pumps, and in the case of a sudden increase or decrease in the amount of water supply, a pressure imbalance occurs by sequentially operating / stopping the plurality of pumps, To avoid the risk of water breakage and pipe rupture.

  In addition, since a large pressure tank is installed as a method for dealing with a sudden increase or decrease in the amount of water supply in a large amount of water supply device, the cost of the water supply device increases and a wide installation space must be secured.

  In the present invention, when the amount of water supply increases rapidly and the pressure cannot greatly satisfy the target pressure value, the operation control starts the pumps sequentially and the operation control starts additional pumps simultaneously. In addition, when the amount of water supply decreases sharply and the pressure greatly exceeds the target pressure value, an operation control switching function for simultaneously stopping a plurality of the pumps is constructed from operation control for sequentially stopping the pumps. .

  That is, the present invention incorporates a plurality of pumps, a pressure sensor that detects the pressure on the discharge side of the pump, and an inverter that changes the rotation speed of the pump so as to become a target pressure value. In a water supply apparatus comprising a control panel that inputs a pressure sensor signal and performs pressure control of the pump, the control panel has a function of setting a target pressure value used for the pressure control, and an input from the pressure sensor The function to calculate the pressure using the value, and when the pump water supply by one or more units increases the water supply water volume and falls below the target pressure value, the stopped pumps are operated sequentially, and by two or more units When the water supply amount decreases during the parallel operation of the pumps and rises above the target pressure value, the pumps that are in operation are sequentially stopped and each has the control function to reach the target pressure value. In place of the control for sequentially operating the stopped pumps when the amount of water supply increases rapidly and the pressure greatly decreases beyond the first predetermined ratio with respect to the target pressure value, the stopped pump Two or more of the pumps are operated simultaneously, and when the amount of water supply decreases rapidly and the pressure greatly increases beyond the second predetermined ratio with respect to the target pressure value, the pumps in operation are sequentially stopped. Instead of the control, the water supply device has a simultaneous control function in which two or more operating pumps are stopped at the same time, and each becomes the target pressure value.

  In addition, the present invention incorporates a plurality of pumps, a feed water amount detection device that detects the feed water amount of the pump, and an inverter that changes the rotation speed of the pump to a target feed water amount value, In the water supply apparatus including a control panel that inputs a signal of the water supply amount detection apparatus and controls the water supply amount of the pump, the control panel sets a target water supply amount value used for the water supply amount control, and A function to calculate the amount of water supply using the input value from the water supply amount detection device, and when the water supply amount increases and falls below the target water supply amount during pump operation with one or more units, the stopped pumps are operated in sequence. In addition, when the water supply amount decreases and rises above the target water supply value during parallel operation of two or more pumps, the operating pumps are sequentially stopped, and the target water supply value When the water supply amount suddenly increases and the water supply amount falls greatly exceeding the third predetermined ratio with respect to the target water supply amount value, the stopped pumps are sequentially operated. In place of control, two or more stopped pumps are operated at the same time, and the amount of water supply decreases rapidly, and the amount of water supply increases greatly exceeding the fourth predetermined ratio with respect to the target water supply amount value. Sometimes, instead of the control to stop the operating pumps in sequence, two or more operating pumps are stopped at the same time, and the water supply device has a simultaneous control function to achieve the target water supply amount value.

  According to the present invention, it is not necessary to install a large pressure tank in the water supply device, and a water supply device using a minimum pressure tank can be realized. The installation space can be used effectively.

The best mode for carrying out the present invention will be described.
Hereinafter, the Example of the water supply apparatus of this invention is described in detail using drawing.

  Example 1 will be described. In FIG. 1, the block diagram of the water supply apparatus of a present Example is shown. 1 is a commercial power supply that supplies power. The inverters 2, 3, and 4 are built in the control panel and have a built-in pump control function. The pumps can be freely changed by driving the pumps 8, 10, and 12 and changing the frequency. Although the water supply apparatus is composed of a plurality of pumps, FIG. 3 shows a configuration example of three pumps. The water sent by the pumps 8, 10, 12 is supplied through the junction pipe 14 via the check valves 9, 11, 13. A pressure tank 15 is attached to the merging pipe 14 in order to suppress pressure pulsation absorption and pressure drop at the start of the pump. In order to detect the pressure, a pressure sensor 16 is attached, and the pressure signal is transmitted to each of the inverters 2, 3, 4 by the cable 5. Cables 6 and 7 are wirings for sending the inverter state to the vacant side. Cables 6 and 7 monitor the other party's state to determine the operation of the own pump, and perform automatic backup when the controller fails. .

  FIG. 2 is a flowchart showing an outline of the present embodiment. As shown in FIG. 2, when the feed water amount is within the normal use water amount range, the normal sequential operation is performed. However, when the feed water amount is suddenly used, the pumps are simultaneously started and simultaneously operated to perform the pump operation. .

  FIG. 3 shows pressure fluctuations and pump operation due to changes in the amount of feed water. FIG. 3 (a) shows that when a change in flow rate occurs within the time range of the time interval Δt1 of the water supply amount Q, the pumps 8, 10, and 12 are sequentially started, and at each start, the discharge pressure interval is shown. A pressure drop of ΔH1 occurs. Generally, the pressure fluctuation range with respect to the target pressure value is within ± 5%. In the case of FIG. 3A, since convergence is within ± 5%, it indicates that normal pump control is being executed.

  Next, FIG.3 (b) has shown the operation | movement when the amount of supplied water is used rapidly. From FIG. 3B, the pumps 8, 10 and 12 are sequentially started even when the flow rate change of the flow rate interval ΔQ occurs during the time interval Δt2 shorter than the time interval Δt1 of FIG. A pressure drop of the discharge pressure interval ΔH2 occurs. Since a pressure drop with a pressure fluctuation range of ± 5% or more occurs, an influence such as water breakage occurs.

  Next, FIG.3 (c) shows the operation | movement at the time of applying a present Example when the amount of supplied water is used rapidly. From FIG. 3 (c), when the flow rate change of the flow rate interval ΔQ occurs during the short time interval Δt2 and the fluctuation ratio exceeds the first predetermined value, the pumps 8, 10, 12 are simultaneously started, It shows that the pressure drops by the discharge pressure interval ΔH3. When this embodiment is applied, the pressure fluctuation width (ratio) converges within ± 5%, and thus the excellent effect of this embodiment is shown.

  In general, when a pressure drop as shown in FIG. 3B occurs, it is necessary to prepare a large pressure tank that can cover the capacity of the pressure drop generated in FIG. However, the large pressure tank is very expensive and requires a wide range of installation space. As described above, in the embodiment of FIG. 3 (c), rapid control for simultaneously starting a plurality of pumps is performed. By performing the above, it is possible to prevent a decrease in discharge pressure with respect to a sudden change in the amount of water supply, and thus stable water supply can be realized.

  In the above embodiment, the case of a sudden increase in discharge pressure due to a sudden increase in the amount of water supply has been described. However, in the case of a sudden decrease in discharge pressure due to a rapid decrease in the amount of water supply, some of the plurality of pumps remain. It is also possible to stop at the same time, and it is also possible to detect and control a sudden increase (decrease) in the amount of feed water instead of a sudden increase (decrease) in the discharge pressure using a feed water amount detection device . At that time, the target water supply amount needs to be changed so as to increase or decrease in accordance with the increase or decrease of the water supply amount.

  In addition, the pressure (feed water amount) value that replaces the normal pump control with the rapid control is when the pressure (feed water amount) value greatly decreases (increases) over a predetermined ratio with respect to the target pressure (feed water amount) value, and these ratios are the same or Can be set differently.

It is a block diagram of the water supply apparatus of an Example. It is a flowchart for the outline | summary of an Example. It is a pressure fluctuation | variation by the change of the amount of feed water, and a pump operation | movement figure.

Explanation of symbols

1 Commercial power supply for driving the inverter 2 Inverter (built-in pump controller)
3 Inverter (Built-in pump controller)
4 Inverter (Built-in pump controller)
5 Pressure signal transmission cable 6 Inverter operation state transmission cable 7 Inverter operation state transmission cable 8 Pump 9 Check valve 10 to prevent water backflow Pump 11 Check valve 12 to prevent water backflow Pump 13 Water backflow Check valve 14 for preventing merging pipe 15 Pressure tank 16 Pressure sensor

Claims (2)

Built-in multiple pumps, a pressure sensor that detects the pressure on the discharge side of the pump, and an inverter that changes the rotational speed of the pump to a target pressure value, and inputs the signal of the pressure sensor And in a water supply apparatus comprising a control panel for controlling the pressure of the pump,
The control panel
A function of setting a target pressure value used for the pressure control, a function of calculating a pressure using an input value from the pressure sensor, and an amount of water supply increased during pump operation by one or more units, When the pressure drops, the pumps that are stopped are operated in sequence, and when the water supply amount decreases and rises above the target pressure value during parallel operation of two or more pumps, the pumps that are operating are stopped sequentially. And each has a control function to achieve the target pressure value,
Instead of controlling the pumps that are stopped in sequence when the amount of feed water suddenly increases and the pressure greatly drops beyond the first predetermined ratio with respect to the target pressure value, Control that two or more units are operated at the same time, and the pumps in operation are sequentially stopped when the amount of water supply decreases rapidly and the pressure rises greatly beyond the second predetermined ratio with respect to the target pressure value. Instead of the above, the water supply device is characterized in that two or more operating pumps are stopped at the same time, and each has a simultaneous control function to achieve the target pressure value. Built-in a plurality of pumps, a feed water amount detection device for detecting the feed water amount of the pump, and an inverter for changing the rotation speed of the pump so as to become a target feed water amount value. In a water supply apparatus comprising a control panel for inputting a signal and controlling the amount of water supplied to the pump,
The control panel
A function for setting a target water supply amount value used for the water supply amount control, a function for calculating a water supply amount using an input value from the water supply amount detection device, and a water supply amount increased during pump operation by one or more units. When the water supply falls below the target water supply amount, the pumps that are stopped are operated in sequence. When the water supply amount decreases and rises above the target water supply amount value during parallel operation of two or more pumps, the pumps are operated sequentially. The pump inside is stopped and has a control function such that each becomes the target water supply amount value,
When the amount of water supply increases rapidly and the amount of water supply falls greatly exceeding the third predetermined ratio with respect to the target water supply amount value, instead of the control for sequentially operating the stopped pumps, When two or more pumps are operated at the same time, and the amount of water supply decreases sharply and the amount of water supply increases greatly exceeding a fourth predetermined ratio with respect to the target water supply amount, the pumps in operation are sequentially Instead of the control to stop at once, a water supply device having a simultaneous control function of simultaneously stopping two or more pumps in operation and achieving the target water supply amount value respectively.

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