JP6591391B2 - Well pump equipment - Google Patents

Description

  The present invention relates to a water supply apparatus, and has a compact structure in which operation means, display means, and control means are integrated with the apparatus main body, and the impeller is rotated at a high speed in a casing so that a predetermined pressure is obtained. The present invention relates to a so-called overflow-type household well water pump that raises, sucks and pushes up water.

  In the prior art, for example, in Patent Document 1, cavitation occurs more by detecting a specific change (a constant rotation speed, a pressure drop and a current drop) from the current value and pressure value during operation of the pump device. When the pressure and current increase while the rotational speed is decreased and the pressure and current are increased, the cavitation has been eliminated, and a pump apparatus using an operation method for detecting cavitation and suppressing the occurrence thereof has been invented.

  Further, Patent Document 2 invents a water supply device that detects the occurrence of cavitation based on a frequency spectrum obtained by acquiring vibration data of a pump with a sensor and Fourier transforming the vibration data.

JP 2010-242511 A JP 2008-309023 A

  In Patent Document 1, which is a conventional technique, a plurality of vortex pump devices that pump a pump by rotating a single motor and rotating an impeller at high speed are attached on the discharge side during operation at a constant rotational speed. When the faucet is further opened, the pressure decreases, the discharge side load decreases, and the current also decreases. Therefore, it may be erroneously detected that cavitation has occurred. If erroneous detection is performed, the rotation speed is decreased while monitoring the pressure and current as a subsequent cavitation suppression operation, and therefore it is not considered that the pressure and flow rate on the discharge side further decrease. Therefore, it is not sufficient to reliably detect the occurrence of cavitation only by monitoring the discharge side pressure and the decrease in the current of the pump device.

  In addition, when cavitation has occurred from the start of operation, the pressure and flow rate on the discharge side are constant although being lower than the original, and the pump device is operated at a constant maximum rotational speed, Since a clear pressure drop and current drop cannot be expected, it is difficult to reliably detect and suppress the occurrence of cavitation.

  In Patent Document 2, which is another example, since a vibration sensor is required to detect the occurrence of cavitation, it is obvious that the manufacturing cost of the device is high.

  In addition, a process for converting and calculating vibration data is required. In particular, in a home-use inexpensive and compact pump device, a ROM that limits the CPU processing capacity and program size of the one-chip microcomputer used. Due to capacity, it may be difficult to realize.

  Although the present invention does not require a special sensor represented by a vibration sensor or the like, it can reliably detect that the pump device is in a lowered pumping performance, represented by the generation of bubbles due to the cavitation phenomenon. It is an object of the present invention to provide a simple pump device. Preferably, when the state is detected, it is not mentioned in the prior art, and when the state is detected, the amount of water on the discharge side is not reduced from the current state. An object of the present invention is to provide a pump device that can be operated with reduced power consumption by lowering the rotational speed.

  The present invention includes an impeller, a motor that rotates the impeller through a shaft, pressure detection means that detects water pressure on the discharge side, water amount detection means that detects the amount of running water pumped to the discharge side, A rotational speed detection means for detecting the rotational speed of the motor; and a motor control means for increasing or decreasing the rotational speed of the motor so that the water pressure on the discharge side becomes an operation target pressure. The motor rotates at the maximum rotation speed that is the upper limit value, and when the detected pressure is less than the predetermined pressure value and the detected water volume is greater than or equal to the predetermined water volume, the maximum rotation speed of the motor is reduced and the rotation speed is reduced. If the water volume Q0 before the lowering and the water quantity Q1 after the lowering are in the relationship of Q0 ≦ Q1, it is estimated that the pumping performance of the pump device is reduced due to the generation of bubbles due to the cavitation phenomenon. And performing the operation with high rotational speed is lowered a predetermined amount.

  ADVANTAGE OF THE INVENTION According to this invention, it is possible to detect automatically the fall of the pumping performance of the pump apparatus resulting from generation | occurrence | production of the bubble by a cavitation phenomenon, without using a special sensor. If it is determined that the pumping performance has been reduced, it is possible to operate with the motor rotating at a lower speed without lowering the flow rate on the discharge side, and as a result, the power consumption of the pump device can be reduced. Become. Since the reduction in power consumption is reflected in the running cost in the form of electric energy (kWh) for the user, it is possible to provide a cost-effective pump device. Further, as a secondary effect, lowering the rotation speed of the motor of the pump device in which bubbles are generated due to the cavitation phenomenon reduces vibration and noise that may be generated by the bubbles, and the impeller rotating at high speed. The impact at the time of the collision between the air bubbles and the bubbles will be alleviated, leading to a longer life of the pump device and a reduction in maintenance costs. Therefore, it is possible to provide a pump device that is highly reliable and advantageous in terms of cost.

Schematic of an example pump device according to an embodiment of the present invention Sectional drawing of the casing part of an example of embodiment of this invention The figure of the operation controller of an example of an embodiment of the invention Block diagram of an example of an embodiment of the present invention The figure which shows the operation of the pumping performance fall detection processing The figure which shows operation of operation processing during pumping performance decline Flow chart of the entire pump device control program Flow chart of pumping performance degradation detection process Flow chart of operation processing during pumping performance decline Normal operation process flow chart

  Hereinafter, embodiments of the present invention will be described.

  The pump device according to the present embodiment includes a water supply unit for pumping water, an impeller having a disk-like outer shape and grooves cut radially on the surface, a casing unit in which the impeller is attached, and the impeller as a shaft. A single motor that rotates via the motor and the impeller rotates at a high speed by rotating the motor to generate an overflow in the fresh water filled in the casing, while pumping water from the water supply unit to the discharge side A discharge unit that pumps and pushes water, a pressure tank that is attached to the discharge unit and can store a certain amount of pumped water, pressure detection means that detects the water pressure on the discharge side, and flowing water that is pumped to the discharge side A water amount detecting means for detecting a water amount, a rotational speed detecting means for detecting the rotational speed of the motor, a current detecting means for detecting a current flowing through the pump device, and a casing; A temperature detecting means for detecting the temperature based on an electric signal from a thermistor attached to the outer wall and whose electric resistance varies depending on the temperature, and a desired discharge side pressure is obtained based on information detected by the detecting means. As shown, the motor control means to increase / decrease the number of rotations of the motor, the operation means consisting of multiple buttons to start and stop the device and make various settings, the device status, the detected pressure and water volume are displayed The display means having a display element and the operation / display control means for controlling the information to be displayed on the display means based on information input from the detection means or the operation means are the main constituent elements. The operation is started by detecting the pressure value that decreases due to the use of water in the motor, and the control is performed to increase or decrease the rotation speed of the motor so that the operation target pressure, which is the retained data, is reached. In the pump device that performs operation control until a pressure equal to or higher than the operation target pressure and less than the operation stop water amount is detected, the rotation speed of the motor rotates at a constant maximum rotation speed that is the upper limit value in the control. If the detected pressure is equal to or less than a predetermined pressure value and the detected water amount is equal to or greater than the predetermined water amount, the detected water amount is stored as Q0. Next, the maximum number of rotations of the motor is decreased by a predetermined amount, the detected amount of water is stored as Q1, the amount of water Q0 before the number of rotations is decreased is compared with the amount of water Q1 after the decrease, and there is no decrease in the amount of water Q0 ≦ Q1 In the case of the above relationship, it is estimated that the pumping performance of the pump device is degraded due to the generation of bubbles due to the cavitation phenomenon, and the operation is further performed by lowering the maximum rotational speed by a predetermined amount.

  As described above, it is possible to reliably detect a decrease in pumping performance of the pump device in the state where bubbles are generated due to cavitation, and in the subsequent operation, the motor speed is higher than the initial maximum speed until the operation release condition is satisfied. Since the rotation speed is low, the power consumption of the motor is reduced, so that it is possible to reduce the power consumption of the pump device that is operating in a state of reduced pumping performance.

  In addition to the maximum rotation speed, the difference between the rotation speed data below the maximum rotation speed or the maximum rotation speed defined as data for detecting the pumping performance deterioration of the pump device due to bubbles generated by the cavitation phenomenon At least three or more pieces of data are held, and the rotational speed is decreased stepwise from N1, N2, and N3 in descending order from the determined maximum rotational speed. The detected water amount during operation at the reduced rotational speed is stored as Q1, Q2, and Q3, and the detected water amount at the previous rotational speed and the detected water quantity at the current rotational speed are compared. The comparisons can be expressed as Q0 ≦ Q1, Q1 ≦ Q2, and Q2 ≦ Q3, respectively. If all the comparison results are true (true), the amount of water will not decrease even if the rotational speed is lowered. Therefore, the maximum rotational speed of the motor is set to N3, which is the lower limit value, without reducing the flow rate on the discharge side. Perform the following operation.

  In addition, if the result of comparison judgment performed stepwise is not established (false), the amount of water has decreased, so the number of revolutions when the condition was established (true) in the previous judgment or the original determination The subsequent operation is performed without increasing the flow rate on the discharge side by increasing the number of rotations of the motor to the maximum number of rotations and performing the subsequent operation.

  Moreover, the determination of the lowered pumping performance performed by reducing the number of revolutions and comparing the amount of water is performed at regular intervals within a range of several tens of seconds to several minutes.

  In addition, it is assumed that the pumping performance has deteriorated, and the amount of water or pressure outside the specified range is detected by operating the faucet on the discharge side during operation at a speed lower than the original maximum speed. If this happens, the motor speed is returned to the original maximum speed, and the motor speed increases or decreases to reach the target pressure within the range that does not exceed the maximum speed. Return to.

  When it is estimated that the pumping performance is in a deteriorated state due to bubbles generated by the cavitation phenomenon, the operation control is switched to a lower rotational speed, and the pumping performance of the pump device is informed to the outside. Change the display contents of the display means.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows an outline of the configuration of the pump device of this embodiment. The pump device main body includes a control controller 3, an operation controller 4, a motor 10, a casing 11 covering an impeller 13 rotated by the motor 10, a thermistor 30 attached to an outer wall of the casing 11, a suction port 1 for taking in pumped water, Check valve 12 for preventing the backflow of water pumped from the suction port 1, discharge port 2 for discharging the taken-in water, pressure sensor 6 for detecting the water pressure on the discharge side, water amount sensor 7 for detecting the water amount on the discharge side, use The main components are a pressure tank 5 that relieves pressure changes due to sudden changes in the amount of water, a power cord 8 that supplies power to the pump device, and a pump cover 9 that covers the pump device.

  FIG. 2 is a cross-sectional view of the casing 11 and the periphery of the pump device. The impeller 13 has a disk-like shape with grooves radially formed therein, and is rotated at a high speed by the motor 10 to generate an overflow in the fresh water filled in the casing 11 to generate water through the suction port 1. While pumping up, water is pumped to the discharge port 2 and pushed up.

  FIG. 3 is a diagram of the operation controller 4 which is an operation and display means of the pump device. The operation controller 4 is a kind of LED that is a light emitting element, and is a three-digit 7-segment LED 22 that can display symbols, numbers, alphabets, etc., and operation / stop switches 15 and 7 that start and stop the operation of the pump device. A display changeover switch 16 for selecting contents to be displayed on the segment LED 22, a pressure LED 18 that emits light when the pressure display is selected, a water amount LED 19 that emits light when the water amount display is selected, and a pressure changeover switch that switches the operation pressure 17. A pressure setting “high” LED 20 and a pressure setting “standard / low (flashing)” LED 21 that emit light for each pressure setting selected for switching, and a reset switch 14 for returning from an abnormal stop state of the pump device.

  FIG. 4 shows a control block diagram of the pump device. The thermistor 30 is a temperature sensor, detects the temperature of the casing 11 of the pump device, the output signal is input to the A / D converter of the control unit 34, and the result converted into digital data is finally one-chip micro It is stored in the RAM in the computer 35. The control unit 34 compares a plurality of temperature threshold data set as data in the ROM in the one-chip microcomputer 35 in advance with the value of the conversion result stored in the RAM, thereby reducing the temperature such as low temperature or high temperature. Abnormality is determined and, if necessary, a warning is displayed on the display means, or the motor 10 is automatically stopped or driven. The pressure sensor 6 is a means for detecting the water pressure on the discharge side, and the water amount sensor 7 is a means for detecting the amount of water flowing through the flow path on the discharge side. The detection result is input to the control unit 34 as an electrical signal, and finally stored in the RAM in the one-chip microcomputer 35 in the same manner as the temperature sensor. The control unit 34 automatically changes the rotational speed of the motor 10 via the drive circuit 36 in accordance with the detected change in pressure and water volume, and controls the discharge pressure to be constant or a predetermined pressure. Further, if necessary, a warning is displayed on the display means, and the detected pressure value or flow rate is displayed. The current sensor 31 detects the current flowing through the pump device, and the detection result is input as an electric signal to the control unit 34. The control unit 34 monitors the current value, and protects the pump device when the current value exceeds a predetermined value. Reduce the rotation speed of the motor 10.

  Next, the Hall IC 32 is used for detecting the position of the rotor of the motor 10. By counting the edges of the output signal per unit time, the speed, that is, the rotational speed can be obtained. The control unit 34 controls the motor 10 via the drive circuit 36 so as to obtain an optimum rotational speed. If the motor 10 is a sensorless type motor, the Hall IC 32 is unnecessary, and the position of the rotor is estimated from the back electromotive force of the motor coil, and the rotational speed is estimated and calculated, and the same control as described above is performed.

  Next, the operation / display unit 33 is in the form of an operation controller as described in the description of FIG. 2, and displays the state of the pump device on the display unit in accordance with a signal from the control unit 34. In addition, the signal level input to the control unit 34 is changed by pressing a switch that is an operation means, and the control unit 34 can detect the state of the switch.

  The control unit 34 includes a one-chip microcomputer 35 incorporating a CPU, ROM, RAM, timer, A / D converter, etc., a drive circuit 36 for driving the motor 10, a current sensor 31 for detecting a current flowing through the pump device, and Consists of peripheral circuits. The control content of the pump device or fixed threshold data is stored in the ROM of the one-chip microcomputer 35 as program data.

  The EEPROM 37 is a ROM that can electrically erase and write data. The one-chip microcomputer 35 stores information by writing information set by the operation / display means 33 as data via a communication interface. Or stored data can be read out. Threshold data and the like whose values can be changed are stored in the EEPROM 37.

  Further, a configuration using a one-chip microcomputer 35 of a type in which a non-volatile memory capable of electrically erasing and writing data represented by the EEPROM 37 is built in the same package and a communication interface is unnecessary is also possible.

  Next, the present embodiment will be described with reference to FIGS. FIG. 5 shows the operation of the pumping performance deterioration detection process, wherein the upper part shows the amount of water and the lower part shows the number of rotations of the motor 10. If an arbitrary amount of water used on the discharge side is constant, the number of rotations of the motor 10 is also constant, and although not shown, the discharge side pressure is also constant. In general, the pump device proportionally increases the pressure and the amount of water on the discharge side as the rotational speed is increased. However, due to the performance of the motor 10 and the impeller 13, the increase in pipe resistance, etc., an increase cannot be expected. For this reason, the maximum rotational speed Nmax that is the upper limit of the rotational speed of the motor 10 is determined for control.

  In FIG. 5, for example, when the water faucet on the discharge side is fully opened, the pressure does not rise to the control target pressure Pt even if it is rotated at the maximum rotation speed Nmax, and the water volume is constant at Q0 because the rotation speed is constant. Become.

  Here, the reduction in pumping performance means that the amount of water used Q, which should be the same, is reduced when the faucet on the same discharge side, the same piping conditions, and the same rotation speed are in operation. . The cause is considered to be the generation of bubbles due to the cavitation phenomenon when the installation environment and the use conditions are the same and there is no wear of parts such as the impeller 13. The pump device according to the present embodiment can detect a decrease in pumping performance caused by bubbles generated by the cavitation phenomenon. When the pumping performance is not lowered, paying attention to the fact that the amount of water is lowered when the rotational speed is lowered as shown in FIG. 5, the rotational speed is repeated from Nmax to N1 at a constant cycle T2 seconds.

  In addition, when the number of rotations is reduced, noise, vibration, or fluctuations in the detection result of pressure and water amount are assumed. Therefore, the water amount Q1 is detected T1 seconds after the start of deceleration, and comparison determination is performed. . The determination of T1, which is the timing of detecting the amount of water when the rotational speed is lowered to N1, is the time during which a stable detection result of the amount of water with little fluctuation is obtained throughout the experiment.

  Next, when T2 is not in a pumping performance degradation state, it is an operation that is repeatedly performed at a constant cycle T2, and thus gives an impression that the device is unstable if deceleration and acceleration are frequently performed at short intervals. Therefore, T2 is characterized by having a period sufficiently longer than T1.

  Moreover, FIG. 5 has shown the case where the fall of pumping performance is not detected.

  By the above, the method of detecting the lowered state of pumping performance is realized.

  FIG. 6 shows the operation of the pumping performance lowering operation process that is switched when it is determined in the pumping performance lowering detection process of FIG. 5 that the pumping performance is in a lowered state.

  FIG. 6 (a) shows a case where the water amount Q0 at the maximum rotation speed Nmax is compared with the water amount Q1 at the rotation speed N1, and Q0 ≦ Q1, and the water amount is unchanged or increased. Lowering the flow rate does not decrease the discharge side flow rate. Subsequently, the rotational speed is reduced from N1 to N2, and the water amount Q2 at the rotational speed N2 is detected and compared with Q1. In the case of FIG. 6 (a), the amount of water becomes Q1> Q2 by reducing the number of revolutions to N2, and the amount of water on the discharge side is reduced. Therefore, the maximum number of revolutions lowered to N2 is increased to N1 to be in a constant state. Thus, the operation is performed by reducing the rotation speed of the motor 10 by the difference of Nmax−N1 without reducing the water volume Q on the discharge side from the water volume Q0 at the maximum rotation speed Nmax.

  6 (b), similarly to FIG. 6 (a), the maximum number of revolutions is decreased to N1 and N2, the amount of water Q2 at the number of revolutions N2 is detected, compared with Q1, and the result is Q1 ≦ Q2 Therefore, when the rotational speed is further lowered to N3, the water amount becomes Q2> Q3, and the water amount is reduced. Therefore, the water amount on the discharge side is reduced. Therefore, the rotational speed is increased to N2 where there is no change in the water amount. By making the state constant, the water amount Q on the discharge side is not decreased from the water amount Q0 at the maximum rotation number Nmax, and the operation is performed with the rotation speed of the motor 10 decreased by the difference of Nmax−N2.

  In FIG. 6 (c), as in FIG. 6 (b), the rotational speed is decreased to N1, N2, and N3, the amount of water Q2 at the rotational speed N3 is detected, and compared with Q1, and the result is Q1 ≦ When the rotational speed is further lowered to N3 because of Q2, the amount of water becomes Q2> Q3, and since the amount of water is reduced, the amount of water on the discharge side is reduced. Therefore, the rotational number is increased to N2 where there is no change in the amount of water. Thus, the water amount Q on the discharge side is not decreased below the water amount Q0 at the maximum rotation number Nmax, and the motor 10 is operated with the rotation speed of the motor 10 decreased by a difference of Nmax−N2.

  From the above, as shown in FIG. 6 (a), FIG. 6 (b), FIG. 6 (c), when the operation is continued in a state where the pumping capacity of the pump device is reduced due to the generation of bubbles due to the cavitation phenomenon, Since it is possible to operate the motor 10 at a lower rotational speed without reducing the amount of water on the discharge side, the power consumption of the pump device can be reduced.

  In addition, the starting conditions of the pumping performance degradation detection process in FIG. 5 shall be that discharge side pressure is less than Ps which is control start pressure, and discharge side water amount is more than control start water amount Qs.

  In addition, the release condition of the operation processing during pumping performance reduction in FIG. 6 is that the discharge side pressure is equal to or higher than Ps that is the control start pressure, or the discharge side water amount is less than the operation stop water amount Qe.

  Next, an outline of program data for realizing this control will be described with reference to FIGS. 7, 8, 9, and 10.

  FIG. 7 is an outline of a control program for the pump device incorporated in the ROM of the one-chip microcomputer 35 mounted on the control unit 34 of the pump device. FIG. 8 shows details of the pumping performance deterioration detection process. FIG. 9 shows details of the operation process during pumping performance degradation. FIG. 10 shows an outline of normal operation processing of the pump device.

  First, when the power supply is turned on, the one-chip microcomputer 35 is reset and the operation of the control program for the pump device in FIG. 7 starts in accordance with the program recorded in the ROM. This will be described below in the order of symbols.

  (A1) is an initialization process, and performs microcomputer I / O port setting, built-in register setting, timer setting, and the like. Here, various setting data relating to the operation of the pump device is also read from the EEPROM 37, and the read data is copied to a predetermined RAM. A timer necessary for capturing input signals from various sensors, outputting output signals, and executing a program at a predetermined cycle is set and the operation is started. Normally only once per reset.

  (A2) detects the input signal from the switch provided in the display / setting means, the input signal from the pressure sensor 6, the water amount sensor 7, the input signal from the current sensor 31, etc. at a constant cycle, This is a sensing process stored in the RAM prepared in the above.

  (A3) This is an element constituting the sensing process. Based on the input signal from the pressure sensor 6, the pressure on the discharge side is calculated at a predetermined cycle, and the result is stored in the RAM prepared as pressure data.

  (A4) This is an element constituting the sensing process. Based on the input signal from the water amount sensor 7, the water amount on the discharge side is calculated at a predetermined cycle, and the result is stored in a RAM prepared as water amount data.

  (A5) Pump operation operation control processing, which includes pumping performance deterioration detection processing, pumping performance lowering operation processing, and normal operation processing.

  (A6) Pumping performance deterioration detection processing and pumping performance lowering operation processing, and if the detection pressure, the detected water amount, and the rotation speed of the motor 10 satisfy the detection start conditions, the rotation speed of the motor 10 is decreased to change the water volume And detect a decrease in pumping performance. Here, when a decrease in pumping performance is detected, the processing shown in FIG. 9 is executed as the operation processing during pumping performance deterioration. Details will be described with reference to FIGS.

  (A7) It is a normal operation process of the pump device when the pumping performance is not lowered, and the discharge side pressure is set to a set pressure based on the detection results of various sensors detected by the sensing process. The process of accelerating / decelerating the motor is performed. The outline is described in FIG.

  (A5) is a display process. By turning off or turning on the 7-segment LED 22 or LED provided in the operation / display means 33, display of the detection result such as the state of the pump device, pressure or water amount, etc. Output signal data for expressing is generated.

  In FIG. 7, (a2), (a3), (a4), (a5), (a6), (a7), and (a8) are processes repeatedly performed with a fixed period.

  Next, the flowchart of the pumping performance deterioration detection process of FIG. 8 is demonstrated.

  (B1) It is determined with reference to the flag set in (b14) whether or not the pumping performance is already decreasing. If the pumping performance is being reduced, the process proceeds to (b10). If not, the process proceeds to (b2).

  (B2) In order to detect a decrease in pumping performance, it is determined with reference to the flag set in (b7) whether or not the process of reducing the maximum rotational speed during normal operation from Nmax to N1 has been performed. If the maximum number of revolutions has been changed to N1, the process proceeds to (b11). If not changed, the process proceeds to (b3).

  (B3) It is determined whether the conditions for starting the pumping performance deterioration detection process are satisfied. The conditions are that the current detected pressure Px is less than Pt which is the target pressure for operation control and is equal to or greater than the control start pressure Ps, the current detected water amount Qx is equal to or greater than the control start water amount Qs, The maximum number of revolutions is Nmax. If these conditions are satisfied, the process proceeds to (b5), and if not satisfied, the process proceeds to (b4).

  (B4) The T2 timer is a timer for measuring the time during which the start condition of the pumping performance deterioration detection process is continued. Since the start condition for the detection process is denied in (b3), the T2 timer is cleared and the process ends.

  (B5) It is determined with reference to the timer T2 whether or not the duration of the start condition of the pumping performance deterioration detection process has elapsed T2 seconds. If T2 seconds have not elapsed, the process ends. If it passes, it will transfer to (b6).

  (B6) The detected water amount Q0 rotating at the maximum rotation speed Nmax is stored in a predetermined RAM, and the process proceeds to (b7).

  (B7) A detection flag indicating that the maximum rotational speed is reduced from Nmax to N1 for the purpose of detecting a decrease in pumping performance is set, and the process proceeds to (b8).

  (B8) During normal operation, the Nmax data copied to the RAM as the maximum rotational speed is updated to N1, and the process proceeds to (b9). The updated maximum rotational speed RAM is used to compare and determine the rotational speed calculated in accordance with the pressure difference and the maximum rotational speed in a normal operation described later, and is controlled so as not to exceed the maximum rotational speed. .

(B9) Start the T1 timer and end the process. The T1 timer determines the timing for taking in the rotating water amount Q1 at the maximum rotation speed N1. At this time, when the maximum rotational speed Nmax is decreased to N1, it takes a certain amount of time to decrease the rotational speed at a predetermined deceleration rate (rpm / second). Therefore, the period of the T1 timer is the time until the fluctuation of pressure and water amount due to the deceleration is stabilized as well as the time required for the deceleration to N1.
(B10) This process is performed when the performance deterioration flag is set, and the pump device performs operation control while the pumping performance is reduced. Details will be described later with reference to FIG.

(B11) Time-up determination of the T1 timer is performed. If T1 seconds have not elapsed, the process ends. If it has elapsed, the process proceeds to (b12).
(B12) The discharge side water amount Q1 when the motor 10 is rotating at a constant rotational speed N1 is stored in the RAM, and the process proceeds to (b13).

  (B13) The water amount Q0 at the rotation speed Nmax stored in the RAM in (b6) is compared with the water amount Q1 stored in (b12). If the determination formula of Q0 ≦ Q1 is true (Y), the process proceeds to (b14) with no change in the water amount. In the case of false (N), it is determined that the amount of water has decreased, and the process proceeds to (b17).

(B14) Even if the rotational speed is decreased from Nmax to N1, the discharge-side water amount does not decrease. Therefore, it is determined that the pumping performance is decreased due to the generation of bubbles due to the cavitation phenomenon, and the performance decreasing flag is set. Move to (b15).
(B15) The data of N1 copied to the RAM as the data of the maximum rotation number is updated to N2, and the process proceeds to (b16).

  (B16) Start the T1 timer and end the process. The T1 timer determines the timing for taking in the rotating water amount Q2 at the maximum rotation speed N2. The Q2 uptake process is performed in the process of lowering the pumping performance shown in FIG.

  (B17) If the number of revolutions is lowered by the determination of (b17) and (b13), it is determined that the pumping performance is not lowered, and the detection flag set in (b7) is cleared and the process proceeds to (b18). To do.

  (B18) The maximum rotation speed data is updated to Nmax which is a normal value. Although omitted in the figure, the timer T2 is reset and the process is terminated in order to obtain the cycle time T2, which is the timing for lowering the maximum rotational speed from Nmax to N1 again.

  As described above, the processing content in the present embodiment is that the pump device is operating in an environment in which a faucet attached to the discharge side is opened and a constant amount of running water is assumed to be used, and the detected pressure P is When the detected water amount Qx is less than the control target pressure Pt, the detection start pressure Ps or more, the detected water amount Qx is the control start water amount Qs or more, and the state at Nmax where the rotation speed of the motor 10 is the maximum rotation speed continues for a predetermined time T2, It is characterized by determining whether the pumping performance is lowered by lowering the pressure to N1 and checking the change in the amount of water. When the pumping performance has not deteriorated, the rotation speed of the motor 10 is increased from N1 to Nmax, which is the original maximum rotation speed, and these series of operations are detected every T2 seconds that are a constant cycle as shown in FIG. As long as the start condition is satisfied, the process is repeated. Here, the difference between the rotational speeds Nmax and N1 is a rotational speed at which the flow rate surely changes if the pumping performance is not deteriorated.

  Further, as the time of T2 which is also the cycle of the repetitive operation is shorter, there is a possibility that noise, vibration or the like due to the rotational speed fluctuation or an impression that the device is unstable may be given. Set it within a few minutes.

  Next, FIG. 9 is a branch destination from FIG. 8 (b <b> 10), and a flowchart of the operation process during pumping performance deterioration will be described.

  (C1) In (c9), which will be described later, a flag that is set when the maximum rotational speed during pumping performance degradation is determined is referred to. If it is set, the process proceeds to (c10). If not set, the process proceeds to (c2).

  (C2) It is determined whether the current maximum rotational speed is N2 set in FIG. 8 (b15). If it is N2, the process proceeds to (c3). Otherwise, the process proceeds to (c11).

  (C3) With reference to the T1 timer started in FIG. 8 (b16), it is determined whether T1 seconds have elapsed. If T1 seconds have not elapsed, the process ends. If it has elapsed, the process proceeds to (c4).

  (C4) Here, since the maximum number of revolutions is changed to N2 and T1 seconds have elapsed, it is possible to detect a highly accurate amount of water with little fluctuation in the number of revolutions, discharge-side pressure, and amount of water. The detected water amount Qx is stored in the RAM as Q2, and the process proceeds to (c5).

  (C5) The water amount Q1 at the maximum rotational speed N1 is compared with the water amount Q2 at the maximum rotational speed N2. The relationship between the rotational speeds is N1> N2, and when Q1 ≦ Q2 is true (Y), the amount of water does not decrease even if the rotational speed is lowered, so the process proceeds to (c6) to further reduce the rotational speed. . When Q1 ≦ Q2 is false (N), it means that the amount of water has decreased. Therefore, the process proceeds to (c8) in order to increase the maximum number of rotations to the number of rotations where no decrease in the amount of water was observed.

  (C6) The maximum rotational speed is updated from the current N2 to N3, and the flow proceeds to (c7). The relationship between the rotational speeds is N2> N3.

(C7) Start the T1 timer and end the process. This process is the same as that shown in FIGS. 8B9 and 8B16, and is a time during which fluctuations in pressure and water volume due to deceleration do not affect the water volume detected next time.
(C8) The maximum number of revolutions is updated from the current number of revolutions N2 to the number of revolutions N1 at which no decrease in the amount of water was observed in the determination of FIG. 8 (b13), and the process proceeds to (c9).

  (C9) The rotation speed confirmation flag is set and the process is terminated. The maximum rotational speed is a value updated to any one of N1, N2, and N3, which is lower than the original value (Nmax), which is also the initial value, and the subsequent operation is updated until the stop condition of the pump device is satisfied. It will be performed at the maximum number of rotations.

  (C10) Normal operation processing of the pump device shown in FIG. 10 is performed.

  (C11) It is determined whether or not T1 seconds have elapsed since the maximum rotational speed is updated to N3. If T1 seconds have not elapsed, the process ends, and the process proceeds to (c12) when T1 seconds have elapsed.

  (C12) The current detected water amount Qx, which is rotating at the maximum rotational speed N3, is stored in the RAM as Q3, and the process proceeds to (13).

  (C13) The water amount Q2 at the maximum rotational speed N2 is compared with the water amount Q3 at the maximum rotational speed N3. The relationship between the rotational speeds is N2> N3, and when Q2 ≦ Q3 is true (Y), the amount of water does not decrease even if the rotational speed is lowered, so it is possible to further reduce the rotational speed, but the maximum rotational speed Since the number N3 is also the speed of control increase / decrease, the process proceeds to (c9) without decelerating. Thereafter, the maximum rotational speed continues to rotate at N3. On the other hand, when Q2 ≦ Q3 is false (N), it means that the amount of water has decreased. Therefore, the process proceeds to (c14) in order to increase the maximum number of rotations to the number of rotations N2 where no decrease in the amount of water was observed.

(C14) The maximum number of revolutions is updated from the current number of revolutions N3 to the number of revolutions N2 in which no decrease in the amount of water was observed in the determination of (c5), and the process proceeds to (c9). Thereafter, the maximum rotational speed continues to rotate at N2.
Next, FIG. 10 shows the contents of the normal operation process of the pump device. (D1) ΔP is a pressure deviation, and the difference between the control target pressure Pt and the current detected pressure Px is calculated, and the process proceeds to (d2).

  (D2) The rotational speed operation amount of the motor 10 corresponding to the pressure deviation ΔP is calculated, and the process proceeds to (d3).

(D3) The rotational speed command value Nt which is the target rotational speed of the motor 10 is calculated by adding the rotational speed manipulated variable to the current rotational speed, and the process proceeds to (d4).
(D4) The rotation speed command value Nt calculated in (d3) is compared with a predetermined maximum rotation speed Nmax determined as data.
If Nt ≧ Nmax, the process proceeds to (d5). If Nt <Nmax, the process proceeds to (d6).
(D5) Since the maximum rotational speed Nmax is an upper limit value in operation control, when the rotational speed command value Nt calculated by the pressure deviation is equal to or higher than the predetermined maximum rotational speed Nmax, the rotational speed command value Nt is set to Nmax. Change to the same value and shift to (d6). In general, the pump device is operated in a region where the rotational speed and the discharge-side pressure are in a proportional relationship, and therefore, the rotational speed is provided with an upper limit rotational speed in terms of control.
(D6) The rotational speed of the motor 10 is increased or decreased at a predetermined acceleration rate or deceleration rate so that the rotational speed of the motor 10 becomes the rotational speed command value Nt.

  With the above processing, the pump device tries to keep increasing the rotational speed until the discharge side pressure becomes equal to or higher than the control target pressure Pt, but if the pressure does not increase, the pump device is operated at a predetermined maximum rotational speed Nmax. .

  As described above, the processing content in this embodiment is that the maximum rotation speed Nmax is described as fixed data on the program, but this is copied to the RAM, and the content of the copied RAM is referred to during the program execution. To do. As a result, it is possible to freely update the data of the maximum number of revolutions as necessary. By switching the maximum number of rotations from a predetermined value Nmax to a predetermined number of rotations N1 lower than Nmax and comparing the amount of water detected during each rotation, it is possible to detect that the pump device is in a pumping performance degraded state Further, the engine is operated with the rotational speed lowered from N1.

  Further, in this example, apart from the maximum rotation speed Nmax which is predetermined data, three types of data are used to detect a decrease in pumping performance and to operate at a rotation speed lower than Nmax in the pumping performance deterioration state. Yes. The data is defined as N1, N2, N3 (Nmax> N1> N2> N3), stored as program data, and the rotational speed is lowered by updating the RAM of the storage destination of the highest rotational speed to the above data step by step. Then, the detection result of the water amount at each rotation number is stored, and the comparison determination with the water amount at the previous rotation number is performed. If there is no change in the water amount, the rotation number is further lowered and the comparison determination is performed. If the water quantity Q does not decrease even if the rotational speed is lowered to the lower limit value N3, the maximum rotational speed in the subsequent operation is N3.

  On the other hand, when the rotation speed is lowered and the amount of water is reduced, the operation is accelerated up to the rotation speed at the time of the determination in the previous stage where there was no change in the water volume, and the subsequent operation is performed with the rotation speed as the maximum rotation speed.

  In addition, the pumping performance deterioration detection processing cycles T1 and T2, which are timings for comparing the water amount before changing the rotational speed with the water amount after changing, are described in the program as numerical data, and a timer built in the one-chip microcomputer 35 By controlling, T1 and T2 that are constant detection cycles can be easily generated.

  In addition, it is determined that the pumping performance has deteriorated, and the faucet operation on the discharge side is performed during operation at any one of the rotation speeds N1, N2, and N3 lower than the originally determined maximum rotation speed Nmax by the set flag. When the amount of water or pressure outside the predetermined range is detected due to the above, the set flag is immediately cleared, and the content of the storage destination RAM of the maximum rotational speed is returned to the original maximum rotational speed Nmax. Thus, the normal operation is returned from the operation processing during the pumping performance deterioration.

  In addition, the pump device is detected by the rotation speed determination flag set in (c9) of FIG. 9 and the pumping performance is detected to be lowered, and is operated at any of the rotation speeds N1, N2, and N3 lower than Nmax. In the display processing of (a8) in FIG. 7, the rotation speed determination flag is referred to. While the flag is set, the 7-segment LED 22 which is numerical data such as the detected pressure or the detected water amount is normally displayed while the flag is set. The display is updated by replacing the display data with, for example, character data such as alphabets, so that the operation state of the pump device can be visually recognized from the outside.

1. Suction port 2. Discharge port Controller for control 4. Operation controller 5. Pressure tank 6. Pressure sensor 7. Water sensor 8. Power cord 9. Pump cover 10. Motor 11. Casing 12. Check valve 13. Impeller 14. Reset switch 15. Run / stop switch 16. Display changeover switch 17. Pressure switch 18. Pressure LED
19. Water LED
20. Pressure setting “High” LED
21. Pressure setting "Standard / Low (flashing)" LED
22.7 segment LED
30. Thermistor 31. Current sensor 32. Hall IC
33. Operation / display means 34. Control unit 35. One-chip microcomputer 36. Drive circuit 37.EEPROM

Claims (4)

Impeller,
A motor for rotating the impeller through a shaft;
Pressure detecting means for detecting the water pressure on the discharge side;
A water amount detection means for detecting the amount of running water pumped to the discharge side;
A rotational speed detection means for detecting the rotational speed of the motor;
Motor control means for increasing or decreasing the rotational speed of the motor so that the water pressure on the discharge side becomes the operation target pressure,
If the motor speed is rotating at the maximum speed that is the upper limit for control, the detected pressure is less than the specified pressure value, and the detected water volume is greater than or equal to the specified water volume, Reduce the number of revolutions,
If the water volume Q0 before the rotation speed is lowered and the water quantity Q1 after the reduction are in the relationship of Q0 ≦ Q1, it is estimated that the pumping performance of the pump device is reduced due to the generation of bubbles due to the cavitation phenomenon, There line driving further lowered by a predetermined amount the maximum speed,
Separately from the maximum rotation speed, the rotation speed data related to the difference between the rotation speed less than the maximum rotation speed or the difference between the maximum rotation speed and the maximum rotation speed is defined as data for detecting the pumping performance degradation due to bubbles generated by the cavitation phenomenon. Have at least three,
When the rotational speed is lowered stepwise from the maximum rotational speed, the water amounts Q1, Q2, and Q3 for the three rotational speed data are in the relationship of Q0 ≦ Q1, Q1 ≦ Q2, and Q2 ≦ Q3. Without reducing the flow rate on the discharge side, the motor is operated at the maximum number of rotations corresponding to the smallest number of rotation data among the three,
If each of the water quantities Q1, Q2, and Q3 does not satisfy the relationship described in claim 2 as a result of decreasing the rotational speed in stages, the operation is performed at the rotational speed corresponding to the rotational speed data that satisfies the relationship. Well pump device characterized in that it performs . In the well pump apparatus according to claim 1,
The well pump apparatus characterized by performing the determination which lowers the said rotation speed in steps for every predetermined period . In the well pump apparatus as described in any one of Claims 1-2,
It is estimated that the pumping performance has declined, and the amount of water or pressure outside the specified range was detected by operating the faucet on the discharge side during operation at a speed lower than the original maximum speed. In this case, the well pump device is characterized in that the rotational speed is returned to the maximum rotational speed, and the rotational speed of the motor is increased or decreased so as to achieve a target pressure within a range not exceeding the maximum rotational speed . In the well pump apparatus as described in any one of Claims 1-3,
Comprising a display means for displaying the state of the well pump device,
When it is estimated that the pumping performance is in a lowered state due to bubbles generated by the cavitation phenomenon, the operation control is switched to a lower rotation speed, and the pumping performance of the pump device is informed to the outside. A well pump device characterized by changing the display content of the display means .

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