Detection device and water supply device

Abstract

To provide a detector capable of detecting failure of a flow rate detector, and a water supplier.SOLUTION: A detector comprises: a flow rate detector that has an impeller with a plurality of blades and magnets, which rotate when subjected to a water flow, and a detection unit that detects the rotation of the magnets and outputs pulse signals based on ON and OFF signals; and a state detector that detects a state of the flow rate detector based on a degree of agreement between output times of the ON signals or between output times of the OFF signals of the pulse signals within a predetermined period.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a detection device and a water supply device.

Background Art

[0002] As a water supply device for supplying water to buildings such as apartment houses, there is known a device that controls the driving of a pump by an inverter based on the pressure detected by a pressure detector provided on the discharge side of the pump.

[0003] Also, as such a water supply device, there is known a device that detects the flow rate on the discharge side of a pump by a flow rate detector and stops the pump when the detected flow rate becomes equal to or less than a predetermined stop flow rate.

[0004] However, in such a water supply device, when the flow rate detector fails, it becomes impossible to appropriately judge the operation of the pump.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] For example, in the above-described flow rate detector, if some blades of the impeller are missing, the output characteristics of the pulse signal may deteriorate. It is difficult to distinguish between the deterioration of the output characteristics of the flow rate detector due to such a failure and the decrease in the output of the flow rate detector due to the decrease in the water supply amount.

[0007] Therefore, an object of the present invention is to provide a detection device and a water supply device capable of detecting the state of a flow rate detector.

Means for Solving the Problems

[0008] A detection device according to one embodiment of the present invention comprises an impeller equipped with a plurality of blades and magnets that rotate when subjected to a water flow, a flow detector having a detection unit that detects the rotation of the magnets and outputs pulse signals in the form of ON signals and OFF signals, and a state detection unit that detects the state of the flow detector based on the degree of agreement between the output times of the ON signals or the output times of the OFF signals of the pulse signals within a predetermined time.

[0009] A water supply device according to one embodiment of the present invention comprises a pump device having a pump and a motor that drives the pump; a flow detector provided on the primary or secondary side of the pump and having an impeller equipped with a plurality of blades and magnets that rotate when subjected to a water flow, and a detection unit that detects the rotation of the magnets and outputs pulse signals in the form of ON signals and OFF signals; and a control unit that controls the operation of the pump device based on the degree of agreement between the output times of the ON signals or the output times of the OFF signals of the pulse signals within a predetermined time. The control unit measures the output time of the ON signal and the output time of the OFF signal of the pulse signal under the conditions that the inverter frequency and pressure are constant. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a detection device and a water supply device that can detect a malfunction of a flow detector. [Brief explanation of the drawing]

[0011] [Figure 1] A front view showing the configuration of a water supply system according to one embodiment of the present invention. [Figure 2] A side view showing a partial cross-section of the water supply system. [Figure 3] A cross-sectional view showing a part of the configuration of the flow detector in the water supply system. [Figure 4] A side view showing the configuration of the impeller of the flow detector. [Figure 5] A plan view showing the configuration of the impeller of the flow detector. [Figure 6] A schematic diagram illustrating the configuration of the magnet installed in the flow detector. [Figure 7]This is an explanatory diagram showing a flow detector with a missing blade. [Figure 8] This is an explanatory diagram showing a flow detector with a missing blade. [Figure 9] This diagram illustrates the waveform of the flow detector under normal conditions. [Figure 10] This diagram illustrates the waveform when the blades of the flow detector are damaged. [Modes for carrying out the invention]

[0012] Hereinafter, a water supply device 1 according to one embodiment of the present invention will be described with reference to Figures 1 to 10. Figure 1 is a front view showing the configuration of the water supply device 1, Figure 2 is a side view showing a partial cross-section of the configuration of the water supply device 1, Figure 3 is a cross-sectional view showing the main components of the flow detector 19 of the water supply device 1, particularly the configuration of the impeller 42, Figure 4 is a side view showing the configuration of the impeller 42 of the flow detector 19, and Figure 5 is a plan view of the configuration of the impeller 42 of the flow detector 19 viewed from the axial direction. Figure 6 is an explanatory diagram schematically showing the configuration of the magnet provided in the flow detector 19. Figures 7 and 8 are explanatory diagrams showing the configuration of the impeller 42 in a state where the blades are missing. Figure 9 is an explanatory diagram showing the waveform of the flow detector 19 in a normal state, and Figure 10 is an explanatory diagram showing the waveform of the flow detector 19 when the blades are missing.

[0013] As shown in Figures 1 and 2, the water supply device 1 (detection device) comprises a plurality of pump devices 11, a plurality of discharge pipes 12 connected to the secondary side of each pump device 11, a plurality of check valves 13 provided in each discharge pipe 12, a plurality of on-off valves 14 provided in each discharge pipe 12, a connecting pipe 15 connecting the plurality of discharge pipes 12, a connecting pipe 16 provided in the connecting pipe 15, a plurality of pressure accumulators 17 provided in the connecting pipe 16, a relief pipe 18 connected to the plurality of pump devices 11, a plurality of flow detectors 19 that detect the flow rate on the secondary side of each pump device 11, a pressure detector 20 that detects the pressure in the connecting pipe 15, and a control panel 21 that controls the operation of each pump device 11. The water supply device 1 pumps water from a water source using the pump devices 11 and supplies water to the destination via the discharge pipes 12 and connecting pipes 15. The water supply device 1 is an example of a detection device that detects a malfunction in the flow detector 19.

[0014] As shown in FIGS. 1 and 2, the pump device 11 includes a motor 31 and a pump 32. The primary side of the pump device 11 is connected to a water source. The pump device 11 is a so-called vertical multi-stage turbine pump in which the rotating shaft extends along the gravitational direction and the motor 31 is disposed above the pump 32. For example, three pump devices 11 are provided.

[0015] The motor 31 is connected to the pump 32 via a rotating shaft. The motor 31 is electrically connected to the control panel 21.

[0016] The pump 32 is driven by the motor 31. The pump 32 has, for example, a suction port 32a and a discharge port 32b that are provided on a side surface of the lower end side of the pump 32 and open in the horizontal direction. For the pump 32, the suction port 32a is connected to a water source, and the discharge port 32b is connected to a discharge pipe 12.

[0017] As shown in FIG. 2, one end of the discharge pipe 12 is connected to the discharge port 32b of each pump 32, and the other end is connected to a connecting pipe 15. One end side of the discharge pipe 12 that is connected to the discharge port 32b extends along the horizontal direction, and the middle part is bent upward along the gravitational direction so that the other end side extends along the gravitational direction. The discharge pipe 12 has a rectifying fin 12a that is provided on one end side of the discharge pipe 12 and whose main surface is arranged along the horizontal direction. The rectifying fin 12a rectifies the water flowing into the discharge pipe 12 from the discharge port 32b.

[0018] As shown in FIG. 2, the check valve 13 is provided, for example, on each discharge pipe 12 on the secondary side of the pump 32 and on the primary side of the connecting pipe 15. The check valve 13 prevents the backflow of water in the discharge pipe 12.

[0019] As shown in FIG. 2, the on-off valve 14 is provided, for example, on each discharge pipe 12 on the secondary side of the pump 32 and on the primary side of the connecting pipe 15. The on-off valve 14 is provided, for example, at a position adjacent to the connection part between the discharge pipe 12 and the connecting pipe 15. The on-off valve 14 opens or closes a flow path continuous from the discharge pipe 12 to the connecting pipe 15.

[0020] As shown in Figures 1 and 2, the connecting pipe 15 connects the other ends of the multiple discharge pipes 12. The connecting pipe 15 also has two open ends on the secondary side of the multiple connected discharge pipes 12, with a closing flange connected to one end and piping that communicates with the water supply destination connected to the other end. The connecting pipe 15 combines the water that has passed through each discharge pipe 12 and forms a flow path to the secondary side that communicates with the connected piping.

[0021] As shown in Figures 1 and 2, the connecting pipe 16 is provided on the connecting pipe 15 and is positioned secondary to the location where the discharge pipe 12 is connected. The connecting pipe 16 is also equipped with multiple accumulators 17. The connecting pipe 16 fluidly connects the multiple accumulators 17 to the connecting pipe 15.

[0022] As shown in Figures 1 and 2, multiple pressure accumulators 17 are provided in the connecting pipe 16. For example, two pressure accumulators 17 are provided. The pressure accumulators 17 are fluidly continuous with the connecting pipe 15 via the connecting pipe 16.

[0023] As shown in Figures 1 and 2, the relief pipe 18 fluidly connects the secondary sides of the multiple pumps 32 to a water source. The relief pipe 18 releases a portion of the water pressurized in the pumps 32 to the water source, preventing the temperature inside each pump 32 from rising.

[0024] The flow detector 19 is configured to detect the flow rate on the primary side or the secondary side of each pump 32. Specifically, as shown in Figures 2 and 3, the flow detector 19 is provided on each discharge pipe 12 so as to detect the flow rate on the secondary side of each pump 32. The flow detector 19 is provided, for example, on the secondary side of the rectifier fin 12a provided on the discharge pipe 12, and on the primary side of the check valve 13 provided on the discharge pipe 12. The flow detector 19 is a flow meter that outputs a signal corresponding to the flow rate. The flow detector 19 transmits the signal to the control panel 21. The flow detector 19 is, for example, an impeller-type flow detector comprising a rotating shaft 41, an impeller 42, and a detection unit 43 that detects the rotation of the impeller 42.

[0025] The rotating shaft 41 is positioned inside the discharge pipe 12 with its axial direction perpendicular to the direction of water flow.

[0026] The impeller 42 is fixed to the rotating shaft 41. As shown in Figures 4 and 5, the impeller 42 has a plurality of blades 42a arranged at equal intervals along the circumferential direction of the rotating shaft, and a magnet 42b arranged in an annular shape around the rotating shaft 41. The impeller 42 rotates the magnet 42b around the rotating shaft 41 as the blades 42a receive the water flow passing through the discharge pipe 12.

[0027] As shown in Figure 6, the magnet 42b is magnetized with six poles, for example, alternating between north and south poles at equal intervals around the rotation axis 41. In other words, the magnet 42b is magnetized with either a north or south pole every 60 degrees around the rotation axis 41.

[0028] The detection unit 43 includes a sensor that detects the rotation of the magnet 42b and a detection board electrically connected to the sensor. The detection unit 43 converts the rotation of the magnet 42b accompanying the rotation of the impeller 42 into a pulse signal. Specifically, the sensor is an alternating detection type Hall IC, which is a magnetic detection element. The Hall IC outputs an ON signal each time the north pole of the magnet 42b approaches, and outputs an OFF signal when the north pole is not approaching, such as when the north pole of the magnet 42b moves away and the south pole approaches. In other words, the Hall IC outputs a pulse signal consisting of a binary signal of an ON signal and an OFF signal. The detection unit 43 is electrically connected to the control panel 21 via signal lines, etc., and transmits the pulse signal output by the Hall IC to the control panel 21.

[0029] When water is supplied, the impeller 42 rotates as water flows through the discharge pipe 12, which is equipped with a flow detector 19, and the flow detector 19 outputs pulse signals consisting of ON and OFF signals. Here, if the impeller 42 is functioning normally, as shown in Figure 5, the multiple blades 42a that receive the water flow are arranged at equal intervals in the direction of rotation, so as shown in Figure 9, the flow detector 19 outputs pulse signals in which the output times of multiple ON signals (ON times) or the output times of OFF signals (OFF times) within a predetermined time are approximately equal. For example, the predetermined time is, for example, the period of one rotation of the impeller (1 period). In this embodiment, as an example, it is set to the period of one rotation of the impeller 42. For example, as shown in Figure 9, the three ON times tn1, tn2, and tn3 within one period are approximately equal, and the three OFF times tf1, tf2, and tf3 within one period are approximately equal.

[0030] On the other hand, as shown in Figures 7 and 8, for example, if some of the blades 42a of the impeller 42 are missing in the flow detector 19, there will be parts of the impeller 42 that do not receive water flow compared to a normal impeller 42. As a result, the ON times of multiple pulse signals within one cycle of one rotation of the impeller output by the flow detector 19 will differ from each other, or from each other, resulting in a difference of a certain value or a certain ratio or more. For example, as shown in Figure 10, the three ON times tn1, tn2, and tn3 within one cycle are different, with tn1 being longer than tn2 and tn3. Also, as shown in Figure 10, the three OFF times tf1, tf2, and tf3 within one cycle are also different, with tf1 being longer than tf2 and tf3.

[0031] As shown in Figure 1, the pressure detector 20 is installed in the connecting pipe 15. The pressure detector 20 is configured to detect the pressure inside the connecting pipe 15. The pressure detector 20 is electrically connected to the control panel 21 via signal lines, etc., and outputs an analog signal to the control panel 21.

[0032] As shown in Figure 1, the control panel 21 comprises an inverter 51, a storage unit 52, a control unit 53 as a state detection unit, and a notification means 54.

[0033] The inverter 51 is electrically connected to the motor 31 and the control unit 53 via signal lines. For example, the same number of inverters 51 as the number of motors 31 are provided. In this embodiment, three inverters 51 are provided. The inverter 51 varies the rotational speed of the motor 31 by varying its frequency.

[0034] The memory unit 52 includes, for example, RAM and ROM, and stores various setting values ​​and calculation formulas. For example, the memory unit 52 stores information sent from various sensors. The memory unit 52 also stores threshold values ​​for stopped flow rates, reference values ​​for fault detection regarding the degree of agreement between multiple ON times, or reference values ​​for fault detection regarding the degree of agreement between OFF times.

[0035] The stop flow rate is the flow rate at which the pump device 11 stops operating. The stop flow rate is, for example, the number of pulses in the pulse signal output by the flow detector 19 when the flow rate passing through the location where the flow detector 19 is installed is the stop flow rate, and this number of pulses is stored in the storage unit 52.

[0036] The degree of agreement is, for example, the degree to which ON times or OFF times match. In other words, if the ON times or OFF times differ, the degree of agreement will be low. The reference value for the degree of agreement, which is used as a criterion for fault detection, is set in advance based on, for example, an acceptable value or range of the difference between ON times or OFF times, or it can be changed by inputting to the control unit. Note that the degree of agreement may be judged using other indicators such as ratios, not just differences.

[0037] The control unit 53 includes a CPU, various processing circuits, and conversion circuits. The control unit 53 controls the operation of the pump device according to information sent from various sensors and various programs stored in the storage unit 52.

[0038] For example, the control unit 53 calculates the flow rate using the number of pulses in the pulse signal received from the flow detector 19 as the detected flow rate value from the flow detector 19. The control unit 53 also converts the signal received from the pressure detector 20 into a pressure value as the detected pressure value from the pressure detector 20. Based on the detected flow rate and pressure values ​​from the flow detector 19 and the pressure detector 20, as well as the information stored in the storage unit 52, the control unit 53 controls each inverter 51.

[0039] Furthermore, the control unit 53 has a function to determine if the flow detector 19 is malfunctioning. The control unit 53 determines if the flow detector 19 is malfunctioning.

[0040] For example, the control unit 53 performs a fault determination at predetermined intervals or when a predetermined judgment condition is met, such as when the flow rate is estimated to be constant.

[0041] As an example, in inverter-equipped products, the control unit 53 makes a fault determination under the conditions that the inverter frequency and pressure are constant. In other words, the control unit 53 determines whether the conditions that the inverter frequency and pressure are constant are met in inverter-equipped products, and if the conditions are met, it determines that the flow detector 19 is faulty; otherwise, it does not determine that the flow detector 19 is faulty. As a condition for determining a fault, for example, if the inverter frequency is within a predetermined fluctuation range, or the pressure is within a predetermined fluctuation range, it may be estimated that the flow rate is constant and a fault determination may be made.

[0042] The control unit 53, in order to determine if the flow detector 19 is malfunctioning, measures the ON time and OFF time of the pulse signal received from the flow detector 19 for one cycle, which is the time it takes for the impeller to complete one rotation. In other words, the control unit 53 measures the output time of each ON signal and each OFF signal for one cycle of the impeller.

[0043] The control unit 53 then compares the output times of the first to last ON-statements and OFF-statements based on the measured ON-statements and OFF-statements. If the degree of agreement between the output times of the first to last ON-statements or OFF-statements is below a predetermined fault criterion, the control unit 53 determines that the flow detector is malfunctioning. For example, the control unit 53 detects that the degree of agreement is below the fault criterion if the difference between the output times of the first to last ON-statements or OFF-statements is greater than or equal to a predetermined value, or falls outside a predetermined tolerance range.

[0044] As a specific example, the control unit 53 detects that the degree of agreement is below a fault criterion value if, for example, the maximum difference between multiple ON times or between multiple OFF times is greater than or equal to a predetermined value, or if the difference between the maximum and minimum ON times or between multiple OFF times falls outside a predetermined allowable range value or allowable range ratio.

[0045] If the detected degree of agreement is below the fault threshold, the control unit 53 will, for example, stop the pump device 11 corresponding to the flow detector 19 and issue a fault notification. That is, for example, the control unit 53 may continue operation while issuing a fault notification, or it may issue a fault notification and stop the pump device 11. Alternatively, it may only stop the pump device 11 or issue a fault notification.

[0046] Furthermore, if the detected degree of agreement is below the fault threshold, the control unit 53 sends an alarm signal to the notification means 54.

[0047] The notification means 54 is configured to notify the control unit 53 of the determination of a malfunction in the flow detector 19 to an external party. The notification means 54 includes, for example, a buzzer that emits a warning sound, or a display unit that displays information about the malfunctioning flow detector 19, to notify the user of the malfunction. The notification means 54 is activated when it receives an alarm signal from the control unit 53.

[0048] With the water supply device 1 configured in this way, a malfunction of the flow detector 19 can be determined from the pulse signal output by the flow detector 19, thus enabling the detection of a malfunction of the flow detector 19 in distinction from a change in the water supply volume.

[0049] For example, when water is supplied by the operation of the pump device 11 in the water supply device 1, water flows into the discharge pipe 12 equipped with a flow detector 19, causing the impeller 42 to rotate and the flow detector 19 to output pulse signals in the form of ON and OFF signals.

[0050] As shown in Figure 5, if the impeller 42 is functioning correctly, the flow detector 19 outputs a pulse signal in which multiple ON times or OFF times within one cycle are approximately equal, because the multiple blades 42a that receive the water flow are arranged at equal intervals in the direction of rotation.

[0051] On the other hand, as shown in Figures 7 and 8, for example, if some of the blades 42a of the impeller 42 are missing in the flow detector 19, there will be parts of the impeller 42 that do not receive water flow compared to a normal impeller 42. As a result, the ON times of multiple pulse signals within one cycle of one rotation of the impeller output by the flow detector 19 will differ from each other, or from each other, resulting in a difference of a certain value or a certain ratio or more.

[0052] Therefore, the control unit 53 can determine if a flow detector 19 is malfunctioning by detecting the degree of agreement between the ON times and OFF times of the pulse signals output by each flow detector 19.

[0053] In this way, the water supply device 1 can determine if the flow detector 19 is malfunctioning based on the pulse signal output by the flow detector 19.

[0054] Furthermore, since the control unit 53 can determine if the flow detector 19 is malfunctioning by comparing multiple detected ON times and multiple OFF times, there is no need to obtain the normal state in advance through experiments or other means. Therefore, malfunctions of the flow detector 19 can be detected more easily than by comparing with the normal state.

[0055] Furthermore, by having the control unit 53 determine if a malfunction occurs at a predetermined timing when the flow rate is estimated to be constant, the computational load on the control unit 53 can be reduced compared to the case where a malfunction of the flow rate detector 19 is always detected.

[0056] Furthermore, the water supply device 1 is configured such that when the control unit 53 detects a malfunction in the flow detector 19, it sends an alarm signal to the notification means 54, which then activates the notification means 54. As a result, the water supply device 1 can notify the user of the malfunction of the flow detector 19 through a warning sound or information display emitted by the notification means 54.

[0057] As described above, according to the water supply device 1 of one embodiment of the present invention, a malfunction of the flow detector 19 can be detected.

[0058] It should be noted that the present invention is not limited to the embodiments described above. For example, although an example in which the flow detector 19 is provided on the secondary side of the pump device 11 has been described, the invention is not limited to this, and the flow detector 19 may be provided on the primary side of the pump device 11. In other words, the installation location of the flow detector 19 can be set as appropriate, as long as it can detect the flow rate of water pumped by the pump device 11.

[0059] For example, in the above embodiment, an example was shown in which the degree of agreement is detected within one cycle based on the time it takes for the impeller to complete one rotation, but the method is not limited to this. For example, the degree of agreement may be detected over a time range spanning multiple rotations.

[0060] In the above embodiment, an example was shown in which a fault is detected in an inverter-equipped product by estimating a constant flow rate state when the pressure and frequency are constant, but the invention is not limited to this. For example, in an inverter-equipped product, a fault may be detected under conditions where the inverter frequency is constant or the pressure is constant. Also, for example, in a non-inverter-equipped product, a fault may be determined under conditions where the pressure is constant (when the pressure is constant). Furthermore, in the above embodiment, an example was shown in which a fault is detected at regular intervals, but the invention is not limited to this, and a fault may be detected at any time when a constant flow rate state can be estimated.

[0061] It should be noted that the present invention is not limited to the embodiments described above, and can be modified in various ways during implementation without departing from its essence. Furthermore, each embodiment may be combined as appropriate, and in that case, the combined effects can be obtained. Moreover, the above embodiments include various inventions, and various inventions can be extracted by selecting combinations from the multiple constituent elements disclosed. For example, if the problem can be solved and effects obtained even if some constituent elements are deleted from all the constituent elements shown in the embodiment, then the configuration with these deleted constituent elements can be extracted as an invention. The following is an appended description equivalent to the invention described in the claims of the original application. (1) A flow detector having an impeller equipped with multiple blades and magnets that rotate when subjected to a water flow, and a detection unit that detects the rotation of the magnets and outputs pulse signals in the form of ON and OFF signals, A detection device comprising: a state detection unit that detects the state of the flow rate detector based on the degree of agreement between the output times of the ON signals or the OFF signals of the pulse signals within a predetermined time period. (2) A pumping device having a pump and a motor that drives the pump, A flow detector is provided on the primary or secondary side of the pump and has an impeller equipped with multiple blades and magnets that rotate when subjected to a water flow, and a detection unit that detects the rotation of the magnets and outputs pulse signals in the form of ON and OFF signals. A water supply device comprising: a control unit that controls the operation of the pump device based on the degree of agreement between the output times of the ON signals or the OFF signals of the pulse signals within a predetermined time period. (3) The control unit measures the output time of the ON signal and the OFF signal of the pulse signal, and controls the motor to stop and notify of a malfunction if the degree of agreement between the output times of the ON signals or the OFF signals of the pulse signal over a predetermined period of time of one or more cycles of the blade is below a standard, or if the difference between the output times of the ON signals or the OFF signals of the pulse signal is above a standard. (2) (4) The water supply device according to (2), wherein the control unit measures the output time of the ON signal and the output time of the OFF signal of the pulse signal when the pressure is constant. (5) It is further equipped with a means of notifying the outside world of information, The water supply device according to (2), wherein the control unit notifies of a malfunction of the flow rate detector by the notification means when the degree of agreement is less than or equal to a failure criterion value. [Explanation of Symbols]

[0062] 1...Water supply device, 11...Pump device, 12...Discharge pipe, 12a...Flow straightening fins, 13...Check valve, 14...On / off valve, 15...Connecting pipe, 16...Connecting pipe, 17...Pressure accumulator, 18...Relief pipe, 19...Flow detector, 20...Pressure detector, 21...Control panel, 31...Motor, 32...Pump, 32a...Suction port, 32b...Discharge port, 41...Rotating shaft, 42...Impeller, 42a...Blades, 42b...Magnet, 43...Detection unit, 51...Inverter, 52...Storage unit, 53...Control unit, 54...Notification means.

Claims

1. A pumping device having a pump and a motor that drives the pump, A flow detector provided on the primary or secondary side of the pump, having an impeller equipped with multiple blades and magnets that rotate when subjected to a water flow, and a detection unit that detects the rotation of the magnets and outputs pulse signals in the form of ON and OFF signals, A water supply device comprising: a control unit that measures the output time of the ON signal and the output time of the OFF signal of the pulse signal under conditions where the inverter frequency and pressure are constant, and controls the operation of the pump device based on the degree of agreement between the output times of the ON signals or the output times of the OFF signals of the pulse signal within a predetermined time.

2. The control unit measures the output time of the ON signal and the OFF signal of the pulse signal, and controls the motor to stop and notify of a malfunction if the degree of agreement between the output times of the ON signal or the OFF signal of the pulse signal over a predetermined period of one or more cycles of the blade is below a standard, or if the difference between the output times of the ON signal or the OFF signal of the pulse signal is above a standard.

3. It is further equipped with a means of notifying information to the outside world. The water supply device according to claim 1, wherein the control unit notifies of a malfunction of the flow rate detector by the notification means when the degree of agreement is below a failure criterion value.

Images