Water supply device

Abstract

To provide a water supply device and a control panel capable of preventing occurrence of water hammering in a case where a pipe is not filled with water.SOLUTION: A water supply device 1 includes: a pump 21; a motor 22 for driving the pump 21; a driving device 31 for driving the motor 22 at variable speed; a check valve 23 disposed at a secondary side of the pump 21; a pressure accumulator 14 disposed at a secondary side of the check valve 23; and a control portion 32 controlling the driving device 31 to start the pump 21 by a normal starting operation when a flow rate detection device 15 detecting flow of water discharged from the pressure accumulator 14 detects the flow of the water discharged from the pressure accumulator 14 when a starting condition of the pump 21 is established, and controlling the driving device 31 to start the pump 21 by a protection starting operation as a starting operation more moderate than the normal starting operation, when the flow rate detection device 15 does not detect the flow of the water discharged from the pressure accumulator 14 when the starting condition of the pump 21 is established.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a water supply system for supplying water to a building. Place Regarding. [Background technology]

[0002] Currently, water supply devices using pumps are known to supply water to buildings. Such water supply devices are known to perform constant target pressure control in order to supply water to the water supply destination of the building at a specified pressure. For example, when the water supply device is installed in a building, or after the water supply device is stopped due to a power outage or a malfunction of the water supply device, there is a risk that air may be present in the building's piping. If the water supply device is operated with air present in the piping, the air is compressed by the water pumped out by the pump, increasing the air pressure, and this increased air pressure is transmitted to the water, which may cause water hammer.

[0003] Therefore, in order to prevent the occurrence of water hammer, a water supply device is known that performs a protective start-up operation when the pump is started for the first time after the water supply device has been stopped due to a power outage or a malfunction of the water supply device, in which the acceleration time of the pump's rotational speed is lengthened so that the increase in discharge side pressure is more gradual than in a normal start-up operation (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-31796 A Summary of the Invention [Problem to be solved by the invention]

[0005] Even after a power outage or after the water supply device is stopped, water hammer will not occur if the piping is filled with water. However, the water supply device described above performs protective start-up operation even under conditions in which water hammer will not occur. For this reason, there is a need to perform protective start-up operation under conditions in which the piping is not filled with water.

[0006] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a water supply device capable of preventing the occurrence of water hammer when water is not filled in the piping. [Means for solving the problem]

[0007] A water supply device according to one aspect of the present invention includes a pump, a motor for driving the pump, a drive device for driving the motor at a variable speed, and a check valve provided on a secondary side of the pump. A pipe connecting a secondary side of the pump and a water supply destination, a branch part provided in the pipe, and a branch pipe provided in the branch part; The check valve is provided on the secondary side. , connected to the branch pipe A pressure accumulator; a pressure detection device provided in the piping and a flow rate detection device provided in the branch pipe, and when the pressure detected by the pressure detection device is equal to or lower than a start pressure for starting the pump, it is determined that a start condition for the pump is satisfied; a control unit that, when a start condition for the pump is satisfied and a flow rate detection device that detects the flow of water discharged from the pressure accumulator detects the flow of water discharged from the pressure accumulator, controls the drive device to start the pump with a normal start-up operation, and, when a start condition for the pump is satisfied and the flow rate detection device does not detect the flow of water discharged from the pressure accumulator, controls the drive device to start the pump with a protective start-up operation that is a slower start-up operation than the normal start-up operation; Equipped with. Effect of the Invention

[0008] According to the present invention, it is possible to provide a water supply device that can prevent the occurrence of water hammer when water is not filled in the piping. [Brief description of the drawings]

[0009] [Figure 1] 1 is an explanatory diagram showing a schematic configuration of a water supply device according to one embodiment of the present invention; [Diagram 2] FIG. 2 is an explanatory diagram showing a schematic configuration of the water supply device. [Diagram 3] FIG. 2 is an explanatory diagram showing a schematic configuration of a control device for the water supply apparatus. [Figure 4] 4 is a flowchart showing an example of a control method for the water supply apparatus. [Diagram 5] FIG. 13 is an explanatory diagram showing an example of a normal start-up operation of the water supply device; [Figure 6] FIG. 13 is an explanatory diagram showing an example of a start-up operation of a conventional water supply device. [Figure 7] FIG. 4 is an explanatory diagram showing an example of a protective start-up operation of a water supply apparatus according to one embodiment. [Figure 8] 13 is an explanatory diagram showing, in a time chart, the protective start-up operation of a water supply apparatus according to another embodiment of the present invention and the driving and stopping of a pump unit during constant target pressure control. FIG. [Figure 9] FIG. 2 is an explanatory diagram showing a schematic configuration of a water supply device according to a reference example. [Figure 10] FIG. 2 is an explanatory diagram showing a schematic configuration of a water supply device according to a reference example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A water supply device 1 according to one embodiment of the present invention will be described below with reference to Figs. Fig. 1 is an explanatory diagram showing a schematic configuration of a water supply apparatus 1 according to one embodiment of the present invention, and Fig. 2 is an explanatory diagram showing a schematic configuration of the water supply apparatus 1. Fig. 3 is an explanatory diagram showing a schematic configuration of a control device 19 used in the water supply apparatus 1, and Fig. 4 is a flow chart showing an example of control of the water supply apparatus. Fig. 5 is an explanatory diagram showing an example of a normal start-up operation of the water supply apparatus 1, Fig. 6 is an explanatory diagram showing an example of a start-up operation of a conventional water supply apparatus, and Fig. 7 is an explanatory diagram showing an example of a protective start-up operation of the water supply apparatus 1 of the embodiment.

[0011] As shown in FIG. 1, the water supply device 1 has a primary side connected to a water source 100 such as a water main or a water tank, and a secondary side connected to a water supply pipe 210 of a building 200 to which water is to be supplied. The water supply device 1 boosts the pressure of water from the water source 100 and supplies it to a water supply faucet 220 such as a tap or shower head connected to the water supply pipe 210. When the water supply device 1 is connected to the water main 110 as the water source 100, the primary side is connected to the water main 110 via a water meter 120 such as a meter unit. In this embodiment, an example in which the water supply device 1 is connected to the water main 110 via the water meter 120 will be described. The water supply pipe 210 includes a standpipe 211 and a horizontal pipe 212 that branches off from the standpipe 211 and is connected to the water supply faucet 220.

[0012] As shown in Figures 1 and 2, the water supply device 1 comprises a pump unit 11, a first flow rate detection device 12 provided in the pump unit 11, a pressure detection device 13 provided on the secondary side of the pump unit 11, a pressure accumulator 14 provided on the secondary side of the pump unit 11, a second flow rate detection device 15 provided between the pressure accumulator 14 and a water supply pipe 210 (water supply destination), and a control device 19 that controls the pump unit 11.

[0013] A single pump unit 11 or a plurality of pump units 11 are provided. In this embodiment, as shown in FIG. 2, an example in which two pump units 11 are provided will be described. The two pump units 11 are connected in parallel. In other words, the two pump units 11 are connected to the branch pipe 16 on the primary side, and the primary side of the branch part of the branch pipe 16 is connected to the water meter 120. The two pump units 11 are connected to the junction pipe 17 on the secondary side, and the secondary side of the junction part of the junction pipe 17 is connected to the water supply pipe 210. The junction pipe 17 has a branch part 17b that branches in two directions on the secondary side of the junction part 17a, and includes a pipe 17c connected to one of the branch parts 17b and a branch pipe 17d connected to the other of the branch part 17b. The pipe 17c is connected to the water supply pipe 210, which is the water supply destination, and the branch pipe 17d is connected to the pressure accumulator 14.

[0014] The pump unit 11 includes a pump 21, a motor 22, and a check valve 23. The pump unit 11 may include an on-off valve on the primary side of the pump 21 and the secondary side of the check valve 23, which is formed to be able to manually open and close the flow path, is used in a constantly open state, and is closed during maintenance or the like. When the pump 21 is driven, it pressurizes water and supplies it to the secondary side. The motor 22 drives the pump 21. The motor 22 has, for example, a stator, a rotor, and a motor shaft, and the motor shaft is connected to the rotating shaft of the pump 21. The motor 22 is connected to the control device 19.

[0015] The check valve 23 is provided on the secondary side of the pump 21. As a specific example, the check valve 23 is provided in the piping at the discharge port of the pump 21 or on the secondary side of the discharge port, and prevents water from flowing back toward the pump 21.

[0016] The first flow rate detection device 12 is a flow rate sensor. The first flow rate detection device 12 is provided in each pump unit 11. The first flow rate detection device 12 is provided on the secondary side of the pump 21 and on the primary side of the check valve 23. The first flow rate detection device 12 is a pump flow rate detection device that detects the flow rate on the secondary side of the pump 21 and on the primary side of the check valve 23. For example, the first flow rate detection device 12 is described using an example in which it is provided on the secondary side of the junction of the junction pipe 17, but it may be configured to be provided on the secondary side of each pump 21, the secondary side of the check valve 23, and the primary side of the junction part 17a of the junction pipe 17.

[0017] For example, the first flow rate detection device 12 may be a paddle type or float type that detects only the stop flow rate, or an impeller type that can detect the flow rate value. The first flow rate detection device 12 is connected to the control device 19 and outputs information on the detected flow rate as a signal.

[0018] The pressure detection device 13 is a pressure sensor. The pressure detection device 13 is provided in the junction pipe 17. The pressure detection device 13 is connected to the control device 19, and outputs information on the detected pressure as a signal.

[0019] The accumulator 14 is, for example, an accumulator. The accumulator 14 can accumulate water at a pressure equal to or higher than the starting pressure. The volume of the accumulator 14 is set appropriately depending on the usage conditions of the water supply apparatus 1, etc. Furthermore, a plurality of accumulators 14 may be installed depending on the usage conditions of the water supply apparatus 1, etc. For example, when the pump unit 11 is stopped and the pressure of the branch pipe 17d, in other words, the pressure of the flow path from the accumulator 14 to the water supply pipe 210, drops to near the starting pressure or to the starting pressure, the volume of the accumulator 14 decreases and water at or above the starting pressure is discharged.

[0020] The second flow rate detection device 15 is a flow rate sensor. The second flow rate detection device 15 is provided in a part of the flow path from the pressure accumulator 14 to the water supply pipe 210. The second flow rate detection device 15 is provided, for example, directly below the pressure accumulator 14. In other words, the second flow rate detection device 15 is provided, for example, in the branch pipe 17d. The second flow rate detection device 15 detects at least the flow of water discharged from the pressure accumulator 14, and outputs the detected information to the control device 19 as a signal.

[0021] The second flow rate detection device 15 is, for example, an impeller type, but a paddle type, a float type, or the like may be used as appropriate as long as it can detect the flow of water discharged from the pressure accumulator 14. The second flow rate detection device 15 may also be the same type of flow rate sensor as the first flow rate detection device 12.

[0022] 2 and 3, the control device 19 is, for example, a control panel. The control device 19 includes a drive device 31 and a control board (control unit) 32.

[0023] The driving device 31 drives the motor 22 at a variable speed. The driving device 31 is an inverter. The number of the driving devices 31 provided is, for example, the same as the number of the pump units 11.

[0024] As shown in FIG. 3, the control board 32 includes, for example, an input device 41, a notification unit 42, a communication unit 43, a storage unit 44, and a control unit 45.

[0025] The input device 41 is an input device that can input information and commands from the outside. The input device 41 is, for example, a key or a button. The input device 41 transmits the input information to the control unit 45. The input device 41 also has a switching means that can switch between an automatic water supply mode that performs automatic water supply control to automatically control the pump unit 11 and a stop mode that does not drive the pump unit 11. The switching means of the input device 41 may be formed to be able to switch to a manual mode in which the pump unit 11 is manually driven in addition to switching between these modes.

[0026] The notification unit 42 is, for example, a display unit that displays information. Furthermore, for example, when an abnormality occurs in the water supply device 1, the notification unit 42 notifies the outside of the abnormality based on information transmitted from the control unit 45. The notification unit 42 includes, for example, a lamp that displays information by lighting or blinking, and a display that displays information.

[0027] The communication unit 43 is configured to be able to transmit and receive information to and from the outside. For example, the communication unit 43 outputs information to the outside wirelessly or via a wire under the control of the control unit 45. For example, the communication unit 43 connects to a processing terminal such as a mobile terminal or a personal computer via a wired or wireless connection, directly or via a network such as the Internet or a LAN (Local Area Network), and transmits and receives various information, commands, and the like.

[0028] The storage unit 44 includes so-called memory and storage. For example, when the automatic mode is selected by the input device 41, the storage unit 44 stores a control program and various parameters for the pump unit 11 in the automatic water supply control. The storage unit 44 stores a starting pressure, which is a pressure value on the secondary side of the pump unit 11 at which the pump unit 11 starts to be driven, and a target pressure on the secondary side of the pump unit 11.

[0029] Here, automatic water supply control refers to a control in which, when the automatic water supply mode is set, the pump unit 11 is driven if the pressure detected by the pressure detection device 13 is the starting pressure, and after the starting operation, the drive device 31 is controlled to variably control the motor 22 so that the target pressure is reached, and the pump unit 11 is stopped if the flow rate detected by the first flow detection device 12 is a predetermined flow rate (stop flow rate).

[0030] In other words, the automatic water supply control is a mode in which the control unit 45 controls the pump unit 11 with constant target pressure control. The constant target pressure control includes constant discharge pressure control in which the discharge pressure on the secondary side of the pump unit 11 is set as the target pressure, and constant estimated terminal pressure control in which the flow path resistance (piping resistance) is taken into consideration.

[0031] The memory unit 44 also stores a control program and various parameters for starting the pump 21 in a normal start-up operation and a protective start-up operation as start-up operations when starting the pump 21 in the automatic water supply control.

[0032] Here, the startup operation refers to, for example, a control operation of pump 21 from the start of pump 21 until the pressure detected by pressure detection device 13 becomes the startup target pressure. The startup target pressure includes a normal startup target pressure used in the normal startup operation and a protective startup target pressure used in the protective startup operation. For example, the normal startup target pressure and the protective startup target pressure are stored in advance in storage unit 44. Here, the startup target pressure is a target pressure used in the above-mentioned constant target pressure control, but may be a target pressure that is set separately from the above-mentioned target pressure and is used only during the startup operation.

[0033] The normal start-up operation is a control operation of the pump 21 in which the pump 21 is controlled based on, for example, the time from when the start-up of the pump 21 is started by determining the start-up pressure stored in advance in the memory unit until the target pressure for normal start-up is reached, the increase in the rotation speed (acceleration), etc.

[0034] The protective start-up operation is, for example, a control operation of the pump 21 in which the pump 21 is controlled based on the time from when the start of the pump 21 is started by determining a start pressure stored in advance in a storage unit until the protective start target pressure is reached, the increase in the rotation speed (acceleration), etc. The protective start-up operation is a control operation of the pump 21 in which the pump 21 is controlled so that the increase in pressure detected by the pressure detection device 13 is more gradual than in the normal start-up operation. In other words, the protective start-up operation is a pressure rise avoidance operation that prevents a sudden (excessive) pressure rise in the flow path by suppressing the pressure rise more than in the normal start-up operation.

[0035] As examples of various parameters for the normal startup operation and the protective startup operation, for example, the memory unit 44 stores a normal startup pressure arrival time T0, which is the time required to reach the normal startup target pressure in the normal startup operation, and a protective startup pressure arrival time T2, which is the time required to reach the protective startup target pressure in the protective startup operation. More specifically, the normal startup pressure arrival time T0 and the protective startup pressure arrival time T2 are the times required for the pressure detected by the pressure detection device 13 to reach the respective startup target pressures, and the control unit 45 controls the drive device 31 to control the acceleration time of the motor 22 so that the startup target pressure is reached within that time.

[0036] Here, the normal startup pressure arrival time T0 is set, for example, to a time during which water hammer will not occur if the secondary flow path of the pump unit 11 is filled with water during the time period from when the pump 21 is driven until the pressure detected by the pressure detection device 13 reaches the startup target pressure, but when there is no water in the secondary flow path of the pump unit 11, there is a risk of water hammer occurring.

[0037] Furthermore, the protection start pressure arrival time T2 is set to a time at which water hammer does not occur, for example, when the pump 21 is driven and the pressure detected by the pressure detection device 13 reaches the protection start target pressure, even if there is no water in the secondary flow path of the pump unit 11. Furthermore, the protection start pressure arrival time T2 is set to a time longer than the normal start pressure arrival time T0.

[0038] The memory unit 44 stores the normal start pressure reaching time T0 and the protection start pressure reaching time T2, which are set in advance.

[0039] The memory unit 44 also stores a threshold value for determining whether or not the secondary side of the pump unit 11 is filled with water in the automatic water supply control, that is, whether or not the pump unit 11 is started in a state in which there is a risk of air being present in the piping on the secondary side of the pump unit 11, including the water supply pipe 210 such as the standpipe 211 and the horizontal pipe 212. Here, the threshold value is the same voltage value as the signal voltage output when the second flow rate detection device 15 detects the flow of water. The memory unit 44 also stores a set time T1, which is arbitrarily set, for determining whether or not the secondary side of the pump unit 11 is filled with water.

[0040] The set time T1 is arbitrarily set in advance depending on the flow path on the secondary side of the pump unit 11, the water supply pipe 210, the performance of the pump unit 11, etc. As a specific example, the set time T1 is a time during which, while the pump 21 is stopped, water is used in the water supply pipe 210 and the pressure in the flow path (pipe) decreases, and the water accumulated in the accumulator 14 is discharged due to this pressure decrease, and until the start of the pump 21, there is no risk of air being present in the flow path (pipe).

[0041] The control unit 45 is, for example, a processor. The control unit 45 controls the drive device 31 as an automatic water supply control in accordance with the program stored in the storage unit 44, starts the pump unit 11 when the pressure detected by the pressure detection device 13 is the start pressure, and stops the pump unit 11 when the flow rate detected by the first flow rate detection device 12 is the stop flow rate. Furthermore, in the automatic water supply control, the control unit 45 controls the pump unit 11 with constant target pressure control so that the target pressure stored in the storage unit 44 becomes the pressure detected by the pressure detection device 13 after the pump unit 11 is started.

[0042] As a specific example, when the automatic water supply mode is selected by the input device 41, the control unit 45 monitors the pressure based on the signal output from the pressure detection device 13 in order to perform automatic water supply control, and when the pressure detected by the pressure detection device 13 falls below the start-up pressure, it determines that the conditions for starting the pump 21 are met and starts the pump unit 11.

[0043] Furthermore, the control unit 45 determines whether the start-up of the pump unit 11 should be a normal start-up operation or a protective start-up operation, and starts up the pump unit 11 with the determined start-up operation.

[0044] For example, when the pressure detected by the pressure detection device 13 becomes the start pressure, the control unit 45 determines whether or not water is discharged from the pressure accumulator 14 and a flow rate is detected by the second flow rate detection device 15. As a specific example, when the pressure detected by the pressure detection device 13 becomes the start pressure, the control unit 45 determines whether or not a signal is output from the second flow rate detection device 15 until the set time T1 stored in the memory unit 44 has elapsed from the time when the pressure detected by the pressure detection device 13 becomes the start pressure.

[0045] If a signal is output from the second flow rate detecting device 15 during the period from when the pressure detected by the pressure detecting device 13 becomes the start pressure until the set time T1, the control unit 45 determines that the flow path is filled with water. In other words, the control unit 45 determines that the normal start-up operation should be performed, and starts the pump unit 11 with the normal start-up operation.

[0046] If no signal is output from the second flow rate detecting device 15 during the period from when the pressure detected by the pressure detecting device 13 becomes the start pressure until the set time T1, the control unit 45 determines that there is a risk of air being present in the flow path. That is, the control unit 45 determines to start up by the protective start-up operation, and starts the pump unit 11 by the protective start-up operation.

[0047] Furthermore, when the pressure detected by the pressure detection device 13 becomes the target pressure at startup due to the normal startup operation or the protective startup operation, the control unit 45 controls the pump unit 11 with constant target pressure control until the flow rate detected by the first flow rate detection device 12 becomes the stop flow rate. Here, for example, if the target pressure at startup is part of the target pressure used in constant target pressure control, the control unit 45 starts the pump unit 11 by the control startup operation or the protective startup operation, and then controls the pump unit 11 with constant target pressure control until the stop flow rate is reached.

[0048] Next, a water supply method using the water supply device 1 configured as above will be described with reference to the flow chart shown in FIG.

[0049] First, the input device 41 is operated by an operator or the like, the automatic water supply mode is selected, power is supplied, and the pump 21 is stopped, that is, during the so-called pump 21 stop state (step ST1), the control unit 45 monitors whether or not a signal is output from the second flow rate detection device 15 (step ST2). For example, when a signal is output from the second flow rate detection device 15, the control unit 45 stores information on the output signal of the second flow rate detection device 15 and information on the time when the signal was received in the memory unit 44. For example, the control unit 45 stores the date and time when the output signal was received, or counts the elapsed time since the signal was received from the second flow rate detection device 15, by using a timekeeping function (clock function) of the memory unit 44 and the control unit 45 that measures time, a timer function that counts the passage of time, or the like.

[0050] The control unit 45 also monitors the output signal from the pressure detection device 13 (step ST2). When the pressure detected by the pressure detection device 13 becomes equal to or lower than the start pressure, the control unit 45 determines that the start condition of the pump 21 is satisfied (step ST3).

[0051] When the pressure detected by the pressure detection device 13 becomes equal to or lower than the start pressure and the start condition is satisfied, the control unit 45 determines whether to perform a normal start operation or a protective start operation (step ST4). As a specific example, the control unit 45 determines whether the second flow rate detection device 15 detects the discharge (flow rate) of water from the pressure accumulator 14 when the start condition is satisfied and during a set time T1 from when the start condition is satisfied to when the start condition is satisfied.

[0052] If a signal is output from the second flow rate detection device 15 within the set time T1 before the start condition is satisfied (YES in step ST4), the control unit 45 determines that the flow path toward the water supply pipe 210 is filled with water due to the water discharged from the pressure accumulator 14, and controls the drive device 31 to perform start-up by normal start-up operation (step ST5). Then, the control unit 45 performs constant target pressure operation control so that the pressure detected by the pressure detection device 13 becomes the normal start-up target pressure (step ST6). Note that in this embodiment, the normal start-up target pressure is part of the target pressure at the constant target pressure, and therefore the normal start-up operation is part of the constant target pressure control, so that the control unit 45 performs constant target pressure control on the pump unit 11 after start-up of the pump unit 11.

[0053] If no signal is output from the second flow rate detection device 15 within the set time T1 before the start condition is satisfied in step ST4 (NO in step ST4), it is determined that there is a risk of air being present in the flow path toward the water supply pipe 210, and the drive device 31 is controlled to perform a start-up using a protective start-up operation (pressure increase avoidance start-up) (step ST7). Then, as the protective start-up operation, when the pressure detected by the pressure detection device 13 reaches the protective start-up target pressure or the protective start-up pressure reaching time T2 has elapsed since the start-up operation of the pump 21 began, the control unit 45 controls the drive device 31 to drive the pump 21 with constant target pressure control (step ST6).

[0054] As described above, after each start-up operation is performed by the water supply device 1, water is supplied by constant target pressure control.

[0055] Next, examples of normal start-up operation and protective start-up operation will be described with reference to Figs. 5 to 7. Fig. 5 shows an example of the frequency and pressure fluctuation of the motor 22 in the normal start-up operation when the start condition is satisfied and a signal is output from the second flow rate detection device 15 during the set time T1 before the start condition is satisfied. Fig. 6 shows an example of the start-up operation when air is present on the secondary side of the pump unit, as in the conventional water supply device. In other words, Fig. 6 shows an example of the frequency and pressure fluctuation of the motor 22 when the normal start-up operation is performed using the water supply device 1 of this embodiment when the start condition is satisfied and a signal is not output from the second flow rate detection device during the set time T1 before the start condition is satisfied (when air is present on the secondary side of the pump unit 11). Fig. 7 shows an example of the frequency and pressure fluctuation of the motor 22 in the protective start-up operation. In Figs. 5 to 7, a multi-story building is assumed as the water supply pipe 210, and the detected pressure A on the 1st floor of the building and the detected pressure B on a floor above the 1st floor are measured.

[0056] When a signal was output from the second flow rate detection device 15 during the set time T1 before the start condition was satisfied, as shown in Figure 5, when normal start operation was performed, the pressure detected on the 1st floor and upper floors increased gradually to the target pressure during normal start as the frequency of the motor 22 increased. In addition, water hammer did not occur.

[0057] On the other hand, when the start condition is satisfied and no signal is output from the second flow rate detection device 15 during the set time T1 before the start condition is satisfied, as shown in Fig. 6, when a normal start operation is performed, the pressure increases gradually as the frequency of the motor 22 increases, but the pressure detected on the 1st floor and upper floors suddenly increases, resulting in a water hammer. This is thought to be because, when the start condition is satisfied, the water in the accumulator 14 has already been discharged and water is being discharged from the water supply valve 220 of the water supply pipe 210, and there is air in the flow path on the secondary side of the pump unit 11, the air in the flow path is suddenly compressed by the operation of the pump 21.

[0058] However, as shown in Fig. 7, when the pump 21 is started by extending the acceleration time as a protective start-up operation in a state where the secondary flow path (inside the piping) of the pump unit 11 is not filled with water, that is, in a state where water hammer occurs as in the example of Fig. 6, the pressure detected on the first floor and upper floors increases gradually as the frequency of the motor 22 increases, and water hammer does not occur. From this, it is clear that the use of this embodiment makes it possible to determine the situation where water hammer occurs. It is also clear that the occurrence of water hammer can be prevented by performing a protective start-up operation when a signal is not output from the second flow detection device during the set time T1 before the start condition is satisfied, which is a condition for water hammer to occur.

[0059] According to the water supply device 1 configured in this manner, when the start conditions for the pump 21 are met and the second flow detection device 15 detects the flow of water discharged from the pressure accumulator 14, the control unit 45 starts the pump 21 with a normal start-up operation, and when the second flow detection device 15 does not detect a water flow, the control unit 45 starts the pump 21 with a protective start-up operation, which is a pressure rise avoidance operation that avoids a sudden pressure rise.

[0060] This makes it possible to determine whether or not there is water in the flow path (piping line) from pump unit 11 to water supply pipe 210, rather than the initial operation of pump 21, thereby preventing unnecessary start-up with protective start-up operation. Also, when air is present in the flow path and there is a risk of water hammer occurring, pump 21 can be started with protective start-up operation. Thus, water supply device 1 can prevent a sudden pressure rise in the flow path caused by compressed air, and prevent water hammer from occurring.

[0061] As described above, according to the water supply device 1 according to one embodiment of the present invention, it is possible to suppress a decrease in followability and prevent the occurrence of water hammer.

[0062] The present invention is not limited to the above-described embodiment. For example, in the above-described example, the control unit 45 controls the pump 21 to operate in the protective start-up operation for the protective start-up pressure arrival time T2 that is longer than the normal start-up pressure arrival time in the normal start-up operation. However, the present invention is not limited to this.

[0063] For example, the control unit 45 may be configured to repeatedly drive and stop the pump unit 11 as the protective start-up operation. In the case of the water supply device 1 performing such a protective start-up operation, the memory unit 44 stores a protective drive time of the pump unit 11 in the protective start-up operation, a protective stop time for stopping the pump 21 after the protective drive time has elapsed, and a cycle count which is the number of cycles of driving and stopping the pump unit 11 during the protective drive time and the protective stop time. Here, the protective drive time is, for example, a time during which water hammer does not occur and the pressure in the piping on the secondary side of the pump unit 11 does not reach the target pressure at startup, and is set in advance as appropriate according to the performance of the pump unit 11, the volume of the piping on the secondary side of the pump unit 11, etc.

[0064] The number of cycles is set to a plurality of times. As shown in Fig. 8, when the number of cycles is a plurality of times, the protection drive time T1 in each water supply is set to, for example, the same time, and similarly, the protection stop time T2 in each water supply is set to, for example, the same time. Note that the plurality of protection drive times T1 may be set to different times, and similarly, the plurality of protection stop times T2 may be set to different times. Also, the protection drive time T1 and the protection stop time T2 may be set to the same time or may be set to different times.

[0065] For example, an example of a time chart of the protection start-up operation and the target pressure constant control automatic water supply mode will be described with reference to Fig. 8. In Fig. 8, an example is shown in which a plurality of protection drive times T1 are the same time, a plurality of protection stop times T2 are the same time, and the number of cycles is set to n=4.

[0066] As shown in Figure 8, in the protective start-up operation, the pump unit 11 is driven for a protective drive time T1, and then the pump unit 11 is stopped for a protective stop time T2. Water is supplied (protective start-up operation) through a protective water supply cycle of driving and stopping the pump unit 11, and water is filled in the piping.

[0067] In this example, this cycle is repeated four times as the number of cycles n, and thereafter, the pump unit 11 is driven under constant target pressure control. That is, the control unit 45 drives the pump unit 11 under constant target pressure control after controlling the pump unit 11 for a predetermined time T0 in the protective start-up operation. The time T0 during which the pump unit 11 is controlled to be driven in the protective start-up operation is calculated by T0=(T1+T2)×n.

[0068] In this way, the protective start-up operation prevents a sudden increase in pressure due to air compression and the occurrence of water hammer by performing the start-up operation by repeating multiple water supply cycles consisting of starting and stopping the pump unit 11. In other words, the protective start-up operation repeatedly starts and stops the pump unit 11, which results in intermittent operation of the pump unit 11 and makes it possible to prevent the occurrence of water hammer.

[0069] In addition, since this type of protective start-up operation is configured to drive the pump unit 11 for the protective drive time, then stop it and stop it for the protective stop time, the drive of the pump unit 11 itself can increase the frequency of the pump 21 by constant target pressure control and accelerating the identification degree, thereby suppressing a decrease in the tracking ability of the pump unit 11.

[0070] In other words, the protective start-up operation, which drives and stops the pump unit 11 for such a number of cycles, is configured to change only the drive and stop times of the pump unit 11 relative to the constant target pressure control, so there is no change in the value commanded to the drive device 31, which drives the motor 22 at a variable speed, and the load related to the control is small.

[0071] The protective start-up operation may be another protective start-up operation. For example, the memory unit 44 may store a plurality of step pressures that are set stepwise from the start of the pump 21 until the target pressure at start-up is reached, and a plurality of holding times for holding the pressure set for each step pressure, and the control unit 45 may be configured to increase the pressure by successive step pressures and repeatedly hold the pressure for the holding time when performing the protective start-up operation. Even when performing such a protective start-up operation, the control unit 45 performs the target pressure constant control until the pressure detected by the pressure detection device 13 reaches the target pressure at start-up or after all steps are executed. The water supply device 1 performing such a protective start-up operation has the same effect as when the other protective start-up operations described above are performed.

[0072] In the above example, the second flow rate detection device 15 is connected to the branch portion 17b on the secondary side of the pump unit 11 and is provided in the branch pipe 17d in which the pressure accumulator 14 is provided, but the present invention is not limited to this. Reference example As described above, the second flow rate detection device 15 may be provided in the pipe 17c that is connected to the branch portion 17b of the junction pipe 17 on the secondary side of the pump unit 11 and is connected to the water supply pipe 210.

[0073] In addition, as shown in Figure 10 Reference example As such, for example, water supply device 1 may not have second flow rate detection device 15, and may use flow rate detection device 15 provided in water supply pipe 210 as the second flow rate detection device.

[0074] In the above example, the control device 19 is a control panel, but the present invention is not limited to this. For example, the control device 19 may be an inverter box. When the control device 19 is an inverter box, the control device 19 may not have, for example, the input device 41 and the notification unit 42 among the above components.

[0075] That is, the present invention is not limited to the above-mentioned embodiment, and various modifications can be made in the implementation stage without departing from the gist of the invention. In addition, the embodiments may be implemented in appropriate combination, and in that case, the combined effect can be obtained. Furthermore, the above-mentioned embodiment includes various inventions, and various inventions can be extracted by combinations selected from the multiple components disclosed. For example, if the problem can be solved and the effect can be obtained even if some components are deleted from all the components shown in the embodiment, the configuration from which the components are deleted can be extracted as an invention. The following provides a description equivalent to the invention described in the original claims of this application. [1] A pump; A motor that drives the pump; a drive device that drives the motor at a variable speed; A check valve provided on the secondary side of the pump; A pressure accumulator provided on the secondary side of the check valve; a control unit that, when a start condition for the pump is satisfied and a flow rate detection device that detects the flow of water discharged from the pressure accumulator detects the flow of water discharged from the pressure accumulator, controls the drive device to start the pump with a normal start-up operation, and, when a start condition for the pump is satisfied and the flow rate detection device does not detect the flow of water discharged from the pressure accumulator, controls the drive device to start the pump with a protective start-up operation that is a slower start-up operation than the normal start-up operation; A water supply device comprising: [2] Further comprising a pressure detection device disposed between the check valve and the pressure accumulator, The control unit determines that the pump start condition is met when the pressure detected by the pressure detection device is equal to or lower than a start-up pressure for starting the pump. [3] Further comprising a pump flow rate detection device disposed between the pump and the check valve, The control unit determines that the pump start condition is met when the pump flow detection device detects a flow rate. [4] A pipe connecting the secondary side of the pump to a water supply destination; A branch portion provided on the pipe; A branch pipe provided at the branching portion, The water supply apparatus according to any one of [1] to [3], wherein the pressure accumulator is connected to the branch pipe. [5] The water supply device is provided with the flow rate detection device, The water supply apparatus according to [4], wherein the flow rate detection device is provided in the branch pipe. [6] The water supply device is provided with the flow rate detection device, The water supply apparatus according to [4], wherein the flow rate detection device is provided on the piping on the water supply destination side relative to the branching portion. [7] A memory unit that stores a protective start pressure reaching time from the start of the pump to the time when a start-up target pressure is reached in the protective start-up operation, The protection start-up pressure reaching time is set to be longer than a time from the start of the pump to the start-up target pressure being reached in the normal start-up operation, The control unit controls the drive device during the protective start-up operation, so that the pressure detected by the pressure detection device becomes the startup target pressure over the protective start-up pressure reaching time, and after the pressure detected by the pressure detection device reaches the startup target pressure, performs constant target pressure control.A water supply device as described in [2] or [3]. [8] A memory unit is provided that stores, during the protective startup operation, a drive time and a stop time of the pump from the start of the pump to the start-up target pressure being reached, and a number of cycles of driving and stopping the pump, The control unit, during the protective start-up operation, controls the drive device to repeatedly drive and stop the pump based on the drive time and the stop time for the number of cycles, and performs constant target pressure control after the pressure detected by the pressure detection device reaches the start-up target pressure.A water supply apparatus as described in [2] or [3]. [9] A memory unit is provided that stores a plurality of step pressures that are set in stages from the start of the pump until the start-up target pressure is reached, and a plurality of holding times for maintaining the pressures set for each of the step pressures, in the protective startup operation; The water supply apparatus described in [2] or [3], wherein, during the protective start-up operation, the control unit controls the drive device so that the pressure detected by the pressure detection device becomes the multiple step pressures, and holds the pressure for the holding time for each step pressure, and performs constant target pressure control after the pressure detected by the pressure detection device reaches the start-up target pressure.

[10] The storage unit stores a set time that is a predetermined time, A water supply apparatus as described in any one of [7] to [9], wherein the control unit, when the pump start condition is satisfied, determines whether the flow detection device has detected a water flow during the set time before the pump start condition is satisfied, and starts the pump with the normal start-up operation or the protective start-up operation.

[11] A drive device that drives a motor that drives a pump at a variable speed; a control unit that, when a start condition for the pump is satisfied and a flow rate detection device that detects the flow of water discharged from a pressure accumulator provided on the secondary side of a check valve provided on the secondary side of the pump detects the flow of water discharged from the pressure accumulator, controls the drive device to start the pump with a normal start-up operation, and, when a start condition for the pump is satisfied and the flow rate detection device does not detect the flow of water discharged from the pressure accumulator, controls the drive device to start the pump with a protective start-up operation that is a slower start-up operation than the normal start-up operation; A control panel comprising: [Explanation of symbols]

[0076] 1...water supply system, 11...pump unit, 12...first flow rate detection device (flow rate detection device for pump), 13...pressure detection device, 14...pressure accumulator, 15...second flow rate detection device (flow rate detection device), 16...branch pipe, 17...junction pipe, 17a...junction section, 17b...branch section, 17c...piping, 17d...branch pipe, 19...control device, 21...pump, 22...motor, 23...check valve, 31...drive device, 32...control board (control unit), 41...input device, 42...alarm section, 43...communication section, 44...memory section, 45...control unit, 100...water source, 110...water main pipe, 120...water meter, 200...building, 210...water supply pipe, 211...standpipe, 212...horizontal pipe, 220...water tap.

Claims

1. A pump, A motor that drives the pump; a drive device that drives the motor at a variable speed; A check valve provided on the secondary side of the pump; A pipe connecting the secondary side of the pump to a water supply destination; A branch portion provided on the pipe; A branch pipe provided at the branching portion; a pressure accumulator provided on a secondary side of the check valve and connected to the branch pipe; A pressure detection device provided in the piping; A flow rate detection device provided in the branch pipe; a control unit that determines that a start condition for the pump is satisfied when the pressure detected by the pressure detection device is equal to or lower than a start pressure for starting the pump, and when the start condition for the pump is satisfied and a flow rate detection device that detects the flow of water discharged from the pressure accumulator detects the flow of water discharged from the pressure accumulator, controls the drive device to start the pump with a normal start operation, and when the start condition for the pump is satisfied and the flow rate detection device does not detect the flow of water discharged from the pressure accumulator, controls the drive device to start the pump with a protective start operation that is a gentler start operation than the normal start operation; A water supply device comprising:

2. A water supply apparatus as described in claim 1, wherein the pressure detection device is arranged between the check valve and the pressure accumulator.

3. a pump flow rate detection device disposed between the pump and the check valve; The water supply apparatus according to claim 1 , wherein the control unit determines that a start condition for the pump is met when the flow rate is detected by the pump flow rate detection device.

4. a storage unit that stores a protective start pressure reaching time from the start of the pump until a start-up target pressure is reached in the protective start-up operation, The protection start-up pressure reaching time is set to be longer than a time from the start of the pump to the start-up target pressure being reached in the normal start-up operation, A water supply device as described in any one of claims 1 to 3, wherein the control unit controls the drive device during the protective start-up operation, so that the pressure detected by the pressure detection device becomes the start-up target pressure over the protective start-up pressure reaching time, and after the pressure detected by the pressure detection device reaches the start-up target pressure, constant target pressure control is performed.

5. a storage unit that stores a drive time and a stop time of the pump from the start of the pump until the start-up target pressure is reached, and a number of cycles of drive and stop of the pump, in the protective start-up operation; A water supply apparatus as described in any one of claims 1 to 3, wherein the control unit, during the protective start-up operation, controls the drive device to repeatedly drive and stop the pump based on the drive time and the stop time for the number of cycles, and performs constant target pressure control after the pressure detected by the pressure detection device reaches the start-up target pressure.

6. a storage unit that stores a plurality of step pressures that are set in stages from the start of the pump until the start-up target pressure is reached, and a plurality of holding times for holding the pressures set for the respective step pressures, in the protective start-up operation; A water supply device as described in any one of claims 1 to 3, wherein the control unit controls the drive device during the protective start-up operation so that the pressure detected by the pressure detection device becomes the multiple step pressures and holds the pressure for the holding time for each step pressure, and performs constant target pressure control after the pressure detected by the pressure detection device reaches the start-up target pressure.

7. The storage unit stores a set time that is a predetermined time, A water supply device as described in any one of claims 4 to 6, wherein the control unit, when the pump start-up condition is met, determines whether the flow detection device has detected a water flow during the set time before the pump start-up condition is met, and starts the pump with the normal start-up operation or the protective start-up operation.

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