Pumping device

Abstract

To provide a pump device which can prevent dew condensation by driving a general-purpose motor while inhibiting increase of manufacturing costs.SOLUTION: A pump device includes: a pump; a motor having a motor fan and configured to drive the pump; a control unit which is provided at the motor and exercises variable speed control of the motor; and a detection device configured to detect environment information. The control unit detects or estimates dew condensation from the environment information detected by the detection device and drives the motor in a dew condensation prevention operation when detecting or estimating the dew condensation. Further, the pump device may include a cover for covering the motor and the control unit as necessary.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a pump apparatus driven by a motor that performs variable speed control.

Background Art

[0002] In a pump apparatus, if condensation occurs on electrical components such as a motor, it becomes a cause of failure. For this reason, a technology capable of preventing condensation in the pump apparatus is demanded. For example, a technology is known that prevents condensation on a motor by controlling the application and non-application of a voltage lower than the startup voltage to the motor coil based on the difference between the ambient temperature and the motor temperature (see, for example, Patent Document 1).

[0003] Furthermore, in a pump apparatus that drives a motor by three-phase drive variable speed control, a technology is also known that prevents condensation by operating the three-phase variable speed control in single-phase operation during stoppage and applying the single-phase output to the AC motor (see, for example, Patent Document 2).

[0004] Furthermore, a technology is also known that prevents condensation inside the motor by potting the motor (see, for example, Patent Document 3).

[0005] Furthermore, when installing the motor, a technology is also known that forms a hole in the lowermost portion to drain generated condensed water out of the motor so that the condensed water does not accumulate.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of Invention

Problems to be Solved by the Invention

[0007] In a motor-driven pump system using variable speed control, the optimal operating method for preventing condensation differs depending on the installation environment. However, optimizing condensation prevention for each installation environment would increase the number of parts and control programs, leading to increased manufacturing costs. Therefore, it is necessary to achieve this while suppressing the increase in manufacturing costs.

[0008] Therefore, the present invention aims to provide a pump device that can prevent condensation by driving a general-purpose motor while suppressing an increase in manufacturing costs. [Means for solving the problem]

[0009] According to one aspect of the present invention, the pump device includes a pump, a motor having a motor fan that drives the pump, and a control unit provided on the motor that controls the motor at a variable speed. A detection device that detects environmental information and , a cover that covers the motor and the control unit, Equipped with 、 The control unit, based on the environmental information detected by the detection device, Inside the cover When condensation is detected or estimated, The motor is driven by an operating method different from normal operation. The motor is driven by condensation prevention operation. The detection device is a temperature detection device provided inside the motor or inside the control unit. The control unit, while the motor is stopped, detects the temperature at first set intervals using the detection device, and estimates condensation if the temperature difference between the temperature detected by the detection device and the maximum temperature while the motor is stopped is higher than a second threshold temperature difference which is a preset temperature difference. . [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a pump device that can prevent condensation by driving a general-purpose motor while suppressing an increase in manufacturing costs. [Brief explanation of the drawing]

[0011] [Figure 1] A block diagram showing an example of the configuration of a pump device according to one embodiment of the present invention. [Figure 2] A side view showing a partial cross-section of the pump system. [Figure 3] A perspective view from above showing the configuration of the motor and control unit of the pump device. [Figure 4] A perspective view showing the configuration of the same motor and control unit from above, with the fan cover of the motor omitted. [Figure 5] A perspective view showing the configuration of the same motor and control unit from below. [Figure 6] A flowchart showing an example of dew condensation detection of the same pump device. [Figure 7] A flowchart showing another example of dew condensation detection of the same pump device. [Figure 8] A flowchart showing still another example of dew condensation detection of the same pump device. [Figure 9] A flowchart showing an example of dew condensation prevention operation of the same pump device. [Mode for Carrying Out the Invention]

[0012] Hereinafter, an example of the pump device 1 according to the embodiment will be described with reference to FIGS. 1 to 9.

[0013] FIG. 1 is a block diagram showing an example of the configuration of the pump device 1 according to one embodiment of the present invention, and FIG. 2 is a side view showing the configuration of the pump device 1 and showing a cover 24 in cross section. FIG. 3 is a perspective view showing the configurations of a motor 21 and a control unit 23 of the pump device 1 from above, and FIG. 4 is a perspective view showing the configurations of the motor 21 and the control unit 23 from above, with a fan cover 36 of the motor 21 omitted. FIG. 5 is a perspective view showing the configurations of the motor 21 and the control unit 23 from below. FIG. 6 is a flowchart showing an example of dew condensation detection of the pump device 1, FIG. 7 is a flowchart showing another example of dew condensation detection of the pump device 1, and FIG. 8 is a flowchart showing still another example of dew condensation detection of the pump device 1. FIG. 9 is a flowchart showing an example of dew condensation prevention operation of the pump device 1.

[0014] The pump device 1 pressure-feeds water to supply water to supply destinations such as a water storage tank and a building. The pump device 1 is a land-mounted type installed on land, and is, for example, installed outdoors.

[0015] As shown in Figure 1 and Figure 2, the pump device 1 includes a motor 21, a pump 22, a control unit 23 that performs variable speed drive control of the motor 21, and a cover 24 that covers at least the sides and upper side of the motor 21 and the control unit 23. Further, as shown in Figure 1, the pump device 1 includes a first sensor 25 as a detection device that acquires environmental information for determining whether condensation occurs in the component parts inside the cover 24 for detecting or estimating condensation inside the cover 24, and a second sensor 26 that acquires information necessary for controlling the motor 21 and the pump 22. For example, the environmental information may be humidity, temperature or the like at the installation location where the pump device 1 is installed, may be temperature, humidity or the like inside the cover 24 of the pump device 1, may be humidity, temperature or the like inside or on the outer surface of the motor 21 and / or the control unit 23, or may be condensation that occurs in any of the component parts inside the cover 24.

[0016] The pump device 1 is a rotating machine apparatus that drives the pump 22, which is a rotating machine, by the motor 21 that is a rotating electric machine. In the pump device 1, the pump 22 is coupled to the motor 21, and a plurality of component parts constituting the control unit 23 are fixed to a plurality of different positions of the motor 21. Further, in the pump device 1, the motor 21 and the pump 22 are fixed by fastening members 99 such as bolts, and the component parts of the control unit 23 are fixed to the motor 21 by fastening members 99 such as screws and bolts.

[0017] The motor 21 is a rotating electric machine. The motor 21 is, for example, a three-phase permanent magnet-mounted synchronous motor or a three-phase induction motor.

[0018] The motor 21 is driven and controlled by the control unit 23. As shown in Figures 4 to 14, the motor 21 comprises a motor shaft 31, a motor casing 32 having a plurality of motor heat dissipation fins 32a on its outer surface as a heat dissipation member, a stator fixed inside the motor casing 32, and a rotor to which the motor shaft 31 is fixed. The motor 21 also has an external fan 35, which is a motor fan, provided at one end in the axial direction, and a fan cover 36 fixed to the motor casing 32 and covering the external fan 35. The motor 21 is connected to the control unit 23 via power lines, which are internal wiring. For example, the motor 21 has a mounting space covered by a component cover 53, on the side of the motor casing 32 opposite to the side to which the pump 22 is connected in the axial direction of the motor shaft 31, where some of the components of the control unit 23 are arranged.

[0019] The motor shaft 31 is a drive shaft that protrudes from both ends of the motor casing 32 in the axial direction. Rotating bodies that rotate in conjunction with the rotation of the motor shaft 31 are connected to both ends of the motor shaft 31, either directly or indirectly. In this embodiment, one end of the motor shaft 31 is connected to the impeller 22b of the pump 22, and the other end of the motor shaft 31 is connected to the external fan 35.

[0020] The motor casing 32 is a motor frame made of a metal material. The motor casing 32 is formed, for example, in a cylindrical shape, and has a plurality of motor heat dissipation fins 32a that extend in the axial direction formed on a part of its outer circumferential surface. The motor casing 32 has a mounting surface on a part of its outer circumferential surface where the motor heat dissipation fins 32a are not provided, and to which a part of the components of the control unit 23 is fixed.

[0021] As shown in Figures 3 to 5, for example, the motor casing 32 comprises a first frame 32A formed in the shape of a bottomed cylindrical frame and a second frame 32B that closes the opening of the first frame 32A.

[0022] The first frame 32A is open on the pump 22 side and closed on the external fan 35 side. The first frame 32A has multiple motor heat dissipation fins 32a and a mounting surface 32b formed on its outer circumference. The first frame 32A also has a first opening formed on its end face through which the other end of the motor shaft 31 is inserted, and multiple first insertion holes 32d through which fastening members 99 such as bolts that fix the first frame 32A to the second frame 32B are inserted.

[0023] The second frame 32B closes the opening on the pump 22 side of the first frame 32A. The second frame 32B has a second opening in the center through which one end of the motor shaft 31 is inserted, and a plurality of second insertion holes 32j through which fastening members 99 such as bolts that fix the first frame 32A are inserted.

[0024] The motor heat dissipation fins 32a are plate-shaped or columnar members that are erected radially outward from the outer circumferential surface of the motor casing 32 and extend in the axial direction of the motor shaft 31. Multiple motor heat dissipation fins 32a are arranged at a predetermined pitch in the circumferential direction on the outer circumferential surface of the motor casing 32, excluding the mounting surface.

[0025] The first insertion hole portion 32d is a projection provided on a part of the outer circumferential surface of the end of the first frame 32A on the pump 22 side, and a hole is formed through which the fastening member 99 is inserted, extending in the axial direction of the motor 21. The first insertion hole portions 32d are provided at multiple locations, in this embodiment three locations, at predetermined intervals in the circumferential direction on the outer circumferential surface of the end of the first frame 32A on the pump 22 side, avoiding the area where the control unit 23 is mounted.

[0026] The second insertion hole portion 32j is a projection provided on a part of the outer circumferential surface of the second frame 32B, extending in the axial direction of the motor 21, and forming a hole into which the fastening member 99 is inserted. The second insertion hole portions 32j are provided, for example, on the outer circumferential surface of the second frame 32B at predetermined intervals in the circumferential direction, in multiple locations, three locations in this embodiment, opposite the multiple first insertion hole portions 32d.

[0027] The external fan 35 is fixed to the motor shaft 31. The external fan 35 is fixed to the motor shaft 31 on the side of the motor casing 32 opposite to the side to which the pump 22 is connected in the axial direction. The external fan 35 rotates in conjunction with the rotation of the motor shaft 31, thereby drawing in air from the axial direction and blowing it radially to the fan cover 36.

[0028] As shown in Figure 3, the fan cover 36 is fixed, for example, on the side of the motor casing 32 opposite to the side to which the pump 22 is connected in the axial direction. The fan cover 36 comprises, for example, a top plate portion 36a with a plurality of ventilation holes 36c formed thereon, located in the area facing the external fan 35, and a skirt portion 36b extending from the top plate portion 36a toward the external fan 35. Note that the fan cover 36 may have cutouts in the area where part of the control unit 23 is located, more specifically, in the top plate portion 36a and skirt portion 36b adjacent to the mounting surface 32b of the motor casing 32.

[0029] The fan cover 36 is fixed to the end of the motor casing 32 by fastening members 99, such as bolts. The inner diameter of the skirt portion 36b gradually increases from the top plate portion 36a side toward the motor casing 32 side, and at the end on the motor casing 32 side, it extends in the axial direction of the motor 21 and is formed to be larger than the outer diameter of the motor casing 32 and the outer diameter of the component cover 53. In other words, a part of the skirt portion 36b is formed in a tapered shape. The skirt portion 36b converts the air blown radially by the external fan 35 into an axial flow of the motor 21 through its tapered inner surface, thereby blowing air axially toward the pump 22 through the gap between the component covers 53 provided at the end of the motor casing 32. As a result, the air blown by the external fan 35 is guided to the outer circumferential surface of the motor casing 32, specifically between the multiple motor heat dissipation fins 32a.

[0030] The mounting space is the space formed by the first frame 32A and the component cover 53 between the closed end face of the first frame 32A and the external fan 35, and some of the components of the control unit 23 are arranged there. In this embodiment, a capacitor mounting substrate and a reactor are arranged in the mounting space.

[0031] Pump 22 is connected to motor 21. Pump 22 is a single-stage or multi-stage pump comprising a pump casing 22a, one or more impellers 22b provided inside the pump casing 22a, and a casing cover 22c that closes the pump casing 22a.

[0032] The pump casing 22a forms a pump chamber that houses the impeller 22b. The pump casing 22a includes a suction port 22d and a discharge port 22e connected to the pump chamber. For example, the pump casing 22a is formed such that flanges 27 provided on the piping can be fixed to the suction port 22d and the discharge port 22e.

[0033] The impeller 22b is either directly connected to the motor shaft 31 of the motor 21, or connected to a rotating shaft that is connected to the motor shaft 31 via a coupling or the like. For example, in this embodiment, the impeller 22b is directly fixed to the motor shaft 31. In such a pump 22, the impeller 22b rotates in conjunction with the rotation of the motor shaft 31, thereby increasing the pressure of the fluid and pumping it to the secondary side.

[0034] The casing cover 22c is fixed to the pump casing 22a and closes the opening of the pump chamber formed in the pump casing 22a. The casing cover 22c is also fixed to the motor 21, thereby fixing the motor 21 to the pump casing 22a.

[0035] The control unit 23 controls the motor 21 at a variable speed. As shown in Figure 4, the control unit 23 comprises a housing 51, a plurality of electrical components for controlling the motor 21 at a variable speed, and a component cover 53. The control unit 23 is configured by arranging first and second components, which are separate sets of electrical components for controlling the motor 21 at multiple different locations on the motor 21, in this embodiment, at two locations. As a specific example, the control unit 23 is integrated with the motor 21 by fixing the housing 51, which houses the first components, to the outer periphery of the side of the motor 21, and the second components are housed in the mounting space (inside the component cover 53). Alternatively, the motor 21 may be configured to house the plurality of electrical components only within the housing 51, without having a mounting space (component cover 53).

[0036] The housing 51 constitutes an electrical box. As shown in Figures 2 to 5, the housing 51 comprises a first case 61 and a second case 62.

[0037] The first case 61 is fixed to the motor casing 32 by fastening members 99 such as screws and bolts. The first case 61 comprises a first body portion 71 formed in the shape of a rectangular dish or bowl having a predetermined depth, and a first flange 72 formed on the outer peripheral edge of the opening end of the first body portion 71. The first body portion 71 is fixed to the motor casing 32, for example, via a packing. The first flange 72 is formed in the shape of a rectangular ring, for example. The first flange 72 is fixed to the second case 62 by fastening members 99.

[0038] The second case 62 is formed of, for example, a metal material with high thermal conductivity, such as aluminum. The second case 62 comprises a second body portion 81 formed in the shape of a rectangular dish or bowl having a predetermined depth, and a second flange 82 formed on the outer peripheral edge of the opening end of the second body portion 81.

[0039] The second body portion 81 has a plurality of heat dissipation fins 81a formed on its outer surface and a contact portion formed on its inner surface that contacts a part of the first component.

[0040] The heat dissipation fins 81a are projections extending in one direction, inclined in the axial direction of the motor 21 and in a direction perpendicular to the axial direction. Multiple heat dissipation fins 81a are arranged side by side with predetermined intervals between them. The heat dissipation fins 81a are configured as heat dissipation parts for the first components inside the housing 51. The contact parts are flat plate-shaped projections that protrude from the inner surface of the second body portion 81, and are formed so that electrical components to which they come into contact can be fixed by fastening members such as bolts and screws.

[0041] The second flange 82 is formed, for example, to have the same shape as the first flange 72 of the first case 61. The second flange 82 is fixed to the first flange 72 via a packing by a fastening member 99.

[0042] Such a control unit 23, as shown in Figure 1, for example, includes a communication unit 91, an input unit 92, an interface 93, a display unit 94, a setting unit 95, an inverter unit 96, a memory 97, and a processor 98. The control unit 23 communicates wirelessly with an external device 200 via the communication unit 91 to send and receive information. In addition, the control unit 23 performs variable speed control of the motor 21 as normal control, and also detects or estimates condensation and drives the motor 21 (pump 22) at a lower rotational speed than normal control as condensation prevention control.

[0043] The communication unit 91 is an arbitrary communication interface controlled by the processor 98 that can communicate with external devices 200 such as external terminals using wireless communication technology. The communication unit 91 may be implemented as, for example, a communication module or a communication board. The communication module may be detachably attached to the control board of the control unit 23 via a connector, for example. Specifically, the communication unit 91 can connect to external devices 200 using wireless communication technologies such as Bluetooth® (e.g., the Bluetooth® Low Energy standard (hereinafter also referred to as the BLE standard)), Wi-Fi®, NFC, and other short-range wireless communication technologies, as well as general-purpose wireless communication technologies including LTE® and other mobile phone lines, and long-range wireless communication technologies including dedicated wireless communication technologies such as Sigfox®.

[0044] Here, the external device 200 is a computer that has a management server, a processor such as a CPU, memory such as ROM or RAM, a display device, an input device, and a communication device, such as an external terminal such as a PC or tablet terminal.

[0045] The input unit 162 includes at least one of the following: a device that accepts user input, such as an operation panel with buttons, a touch panel, a keyboard, or a mouse; and a sensor, such as a pressure sensor, a microphone, or a camera. The input unit 162 is a device that accepts user input, which is any command from the user, such as parameter settings or settings for each operating mode. Electrical signals from the input unit 92 are supplied to the processor 98 via the bus.

[0046] Interface 93 is a terminal or circuit to which the first sensor 25 and the second sensor 26, as well as external terminals, can be electrically connected. Furthermore, if a water receiving tank is provided on the primary or secondary side of the pump device 1, and an electrode rod for controlling the liquid level in the water receiving tank is provided, the interface 93 is electrically connected to the electrode rod.

[0047] The display unit 94 displays various data. The display unit 94 can be any display capable of displaying information, such as a CRT display, liquid crystal display, organic EL display, LED display, or plasma display, or a light-emitting element such as an LED that displays information by emitting light.

[0048] The setting unit 95 is an input unit that physically sets the electrical connection state for acquiring read parameters among the control parameters. For example, a DIP switch or jumper pins may be used as the setting unit 95. Alternatively, the input unit 92 may have the function of the setting unit 95.

[0049] The inverter unit 96 includes a circuit board, power circuit elements, a capacitor board including a converter circuit, a smoothing capacitor, and an inverter circuit, a reactor, and a noise filter. The inverter unit 96 supplies AC power of a predetermined frequency to the motor 21. The inverter unit 96 also receives inverter control signals from the processor 98. The inverter unit 96 operates in accordance with the inverter control signals. For example, the inverter unit 96 stops or starts operation in accordance with an inverter control signal corresponding to an operation stop signal or an operation start signal. The inverter unit 96 also controls the rotational speed (rotational velocity) of the motor 21 by varying the frequency (operating frequency) in accordance with an inverter control signal corresponding to a rotational speed control signal.

[0050] Memory 97 is capable of reading and writing data. Memory 97 stores data used by the processor 98, operating data for the motor 21 and pump 22, and various data and programs used to control the motor 21. Memory 97 is a ROM, RAM, HDD, SSD, integrated circuit storage device, etc., that stores various types of data.

[0051] Memory 97 stores various control settings as control information, such as starting pressure, stopping flow rate, target pressure, acceleration time, deceleration time, PI control setting value, first maximum operating frequency, second maximum operating frequency, and minimum operating frequency. Storage device 57 stores various processing programs, such as a program to control the motor 21 with constant target pressure control during normal operation, a program to determine condensation based on environmental information, and a program to control the motor 21 as a condensation prevention operation when condensation is detected. Memory 97 also stores various parameters for these processing operations. Here, condensation prevention operation means operating the motor 21 and pump 22 at a rotational speed, current value, or a first set rotational speed that is lower than the rotational speed, current value, or power value of the motor 21 during normal operation (normal operation).

[0052] The processor 98 is an arithmetic unit such as a CPU or microprocessor. The processor 98 may also be composed of dedicated circuits such as an ASIC or FPGA. The processor 98 is a control unit that executes various programs stored in the memory 97 to realize the functions of a management device, such as an acquisition unit that acquires operating information of the motor 21 and pump 22, a determination unit that determines condensation, and a communication control unit that controls the communication unit 91 to send and receive operating information, determination information, various programs, and various parameters.

[0053] The cover 24 covers the sides and top of the motor 21, the top of the pump 22, and the sides and top of the housing 51 of the control unit 23. For example, the cover 24 is formed in the shape of a rectangular box with an open bottom. The cover 24 comprises, for example, a rectangular top plate portion 24a and a rectangular cylindrical peripheral wall portion 24b provided on the periphery of the top plate portion 24a and hanging down from the top plate portion 24a.

[0054] The top plate portion 24a faces the top plate portion 36a of the fan cover 36 of the motor 21 at a predetermined distance. One surface of the peripheral wall portion 24b faces the second body portion 81 of the second case 62 of the housing 51 of the control unit 23 at a predetermined distance. Also, one surface of the top plate portion 24a facing the housing 51 is spaced apart from the heat dissipation fins 81a formed on the second body portion 81 of the housing 51. For example, the gap between the top plate portion 24a and the top plate portion 36a of the fan cover 36 is larger than the gap between one surface of the peripheral wall portion 24b and the second body portion 81.

[0055] The first sensor 25 is a detector that acquires information about the environment at the installation location of the pump device 1, information about the environment inside the cover 24, or information about the internal or external environment of components provided inside the cover 24, which is necessary for the processor 98 to determine whether condensation has occurred inside the cover 24 as part of the condensation determination process. For example, the first sensor 25 is at least one of the following: a water leak (liquid leak) detection device, a humidity detection device, and a temperature detection device.

[0056] The water leak detection device has, for example, an electrode section containing two electrodes. When no water adheres to the electrode section, it opens, and when water adheres to the electrode section, it short-circuits the electrodes, outputting signals corresponding to the open state and short-circuit state to the control unit 23. For example, the water leak detection device is installed inside or below the outer surface of the motor 21, inside or below the outer surface of the control unit 23, inside or below the outer surface of the housing 51, or below inside the cover 24, such as the pump casing 22a and / or casing cover 22c. For example, the water leak detection device is installed in a position where condensation water flows and accumulates when condensation occurs inside the cover. The water leak detection device may also be configured to use a fiber sensor that irradiates light onto the position where condensation water accumulates, acquires the reflectance, and detects the condensation water.

[0057] The humidity detection device is installed inside the cover 24. The humidity detection device is configured to detect the humidity inside the cover 24. The humidity detection device outputs a signal corresponding to the detected humidity to the control unit 23. The humidity detection device may also be installed inside or outside the motor 21, inside or outside the control unit 23, etc.

[0058] The temperature detection device is configured to detect the temperature of the inside or outside of the motor 21, the temperature of the inside or outside of the control unit 23, the temperature inside the cover 24, or the ambient temperature. The temperature detection device outputs a signal corresponding to the detected temperature to the control unit 23.

[0059] The second sensor 26 is a detector that acquires information necessary for controlling the motor 21 and the pump 22. The second sensor 26 is a pressure sensor and / or a flow sensor. The second sensor 26 is electrically connected to the control unit 23 and outputs a signal corresponding to the acquired pressure or flow rate to the control unit 23. The pressure sensor detects the pressure on the primary and / or secondary side of the pump 22 and outputs a signal corresponding to the detected pressure to the control unit 23. The flow sensor detects the flow rate on the primary and / or secondary side of the pump 22 and outputs a signal corresponding to the detected flow rate to the control unit 23.

[0060] Next, an example of a control method for the pump device 1 according to the embodiment will be described using Figures 6 to 9. First, as a control method for the pump device 1, a condensation determination process that determines the occurrence of condensation using the first sensor 25 will be described. Note that the condensation determination process differs depending on the type of sensor used for the first sensor 25. As a first example, the condensation determination process using a water leak (liquid leak) detection device for the first sensor 25 will be described using the flowchart in Figure 6. As a second example, the condensation determination process using a humidity detection device for the first sensor 25 will be described using the flowchart in Figure 7. As a third example, the condensation determination process using a temperature detection device for the first sensor 25 will be described using the flowchart in Figure 8.

[0061] First, the condensation detection process for the first example will be explained. When the pump device 1 is energized and the motor 21 is stopped, or when the motor 21 is running, the processor 98 determines whether or not a water leakage signal is output from the first sensor 25, which is a water leakage detection device (step ST11).

[0062] When a water leakage signal is input from the first sensor 25 (YES in step ST11), the processor 98 determines that condensation has been detected (condensation detection determination) (step ST12). Specifically, if water comes into contact with the electrodes of the water leakage detection device, which is the first sensor 25, and a short circuit occurs between the electrodes, the processor 98 determines that the short circuit is due to condensation.

[0063] If no water leakage signal is input from the first sensor 25 (NO in step ST11), it is determined that condensation has not been detected (determination of no condensation detected) (step ST13). Specifically, if there is no short circuit between the electrodes of the water leakage detection device, which is the first sensor 25, and the electrodes are open, the processor 98 determines that condensation has not occurred. In this way, as the condensation determination process in the first example, the processor 98 monitors the first sensor 25 and continues the condensation determination process until, for example, the power supply to the pump device 1 is stopped.

[0064] In the condensation detection process of the first example, it is preferable that the resistance measurement value of the first sensor 25 has a resistance difference (hysteresis) in advance to prevent chattering during short circuits and open circuits.

[0065] Next, the condensation determination process of the second example will be explained. When the pump device 1 is energized and the motor 21 is stopped, or when the motor 21 is running, the processor 98 acquires a signal corresponding to the humidity detected by the first sensor 25, which is a humidity detection device, and compares the acquired humidity with a first threshold value, which is the humidity value at which condensation occurs and is stored in the memory 97 in advance, to determine whether the occurrence of condensation can be estimated (step ST21). As a specific example, the processor 98 determines whether the humidity detected by the first sensor 25 is greater than the first threshold value.

[0066] If the humidity detected by the first sensor 25 is greater than the first threshold (YES in step ST21), it is estimated that condensation has occurred or is likely to occur, and it is determined that estimated condensation has been detected (estimated condensation detection determination) (step ST22).

[0067] If the humidity detected by the first sensor 25 is below the first threshold (NO in step ST21), it is estimated that condensation has not occurred or there is almost no risk of condensation occurring, and it is determined that no estimated condensation has been detected (determination of no estimated condensation detected) (step ST23). In this way, as the condensation determination process in the second example, the processor 98 performs an estimated condensation determination process to estimate the occurrence of condensation from the humidity detected by the first sensor 25, for example, until the power supply to the pump device 1 is stopped.

[0068] In addition, in the condensation detection process of the second example, chattering prevention may be performed by introducing a humidity difference (hysteresis) between the high humidity where condensation is estimated to occur and the low humidity where condensation is estimated not to occur.

[0069] Next, the condensation determination process for the third example will be explained. First, the processor 98 drives the pump 22 and then determines that it has stopped (step ST31). The first sensor 25, which is a temperature detection device, detects the temperature immediately after the pump 22 has stopped, and stores the detected temperature immediately after the pump 22 has stopped in the memory 97 (step ST32).

[0070] Next, the processor 98 detects the temperature with the first sensor 25 at predetermined intervals, which are set in advance and stored in the memory 97, and stores the temperature detected each time in the memory 97 (step ST33). For example, the processor 98 sets the temperature immediately after the pump 22 stops, detected in step ST32, as the maximum temperature, and then, in step ST33, it uses the temperature detected at predetermined intervals as the current temperature and updates the memory 97 with the current temperature detected each time.

[0071] Next, the processor 98 calculates the temperature difference (maximum temperature - detected temperature) between the maximum temperature, which is the temperature immediately after the pump 22 stops, and the current temperature (detected temperature), which is detected and updated at the first set time intervals. It then compares this calculated temperature difference with a second threshold, which is a temperature difference pre-stored in memory 97 that may cause condensation (step ST34). Here, the difference between two different temperature values ​​for the second threshold is the amount of temperature decrease, and a value that may cause condensation due to the condensation of moisture in the air is pre-set. Specifically, the processor 98 determines whether the difference between the maximum temperature and the current temperature is greater than the second threshold.

[0072] If the difference between the maximum temperature and the current temperature is greater than the second threshold (YES in step ST34), it is estimated that condensation is occurring, and it is determined that estimated condensation has been detected (estimated condensation detection determination) (step ST35).

[0073] If the difference between the maximum temperature and the current temperature is less than or equal to the second threshold (NO in step ST34), it is estimated that condensation has not occurred or is unlikely to occur, and it is determined that no estimated condensation has been detected (determination of no estimated condensation detection), and the process returns to step ST33. Then, the processor 98 uses the temperature detected by the first sensor 25 when the first set time has elapsed as the current temperature (detected temperature) and proceeds with the processing from step ST33 onward. In this way, as the condensation determination process in the third example, the processor 98 periodically performs an estimated condensation determination process at each set first set time interval, estimating the occurrence of condensation based on the temperature detected by the first sensor 25.

[0074] Furthermore, in the third condensation determination process, hysteresis may be introduced between the temperature difference in which condensation is estimated to occur and the temperature difference in which condensation is estimated not to occur to prevent chattering. Also, the third condensation determination process may be configured not to be performed for a certain period of time depending on the previous pump operation time, or within a second set time that is pre-set and stored in memory 97, since residual heat remains immediately after the pump 22 stops, as this occurs after the motor 21 has heated up. In other words, the third condensation determination process may be configured to detect and store the temperature with the first sensor 25 as the maximum temperature immediately after the pump 22 stops (steps ST31, ST32), and then not perform the third condensation determination process until a time corresponding to the pump operation time (motor drive time) or the second set time has elapsed, and then perform the process from step ST33 onwards after the cooling period has elapsed. This is because, during the cooling period, the temperature inside the motor 21 is also high, resulting in a large amount of saturated water vapor and making condensation less likely.

[0075] Next, as another control method for the pump device 1, an example of a condensation prevention operation process when condensation detection (estimated condensation detection) is performed in any of the condensation determination processes in the first to third examples will be explained using the flowchart in Figure 9.

[0076] First, the processor 98 performs a condensation determination process while the pump 22 is stopped (step ST41). In the condensation determination process, the processor 98 performs a condensation detection determination or an estimated condensation detection determination (step ST42), and then starts operating the motor 21 and pump 22 at a first set rotational speed lower than the normal operation in which the motor 21 and pump 22 are driven with constant target pressure control as normal operation (step ST43). Since the first set rotational speed is lower than the normal operation speed, excessive heat generation of the motor 21 is suppressed, and as the external fan 35 rotates, air flows as shown by the arrow in Figure 2. Therefore, the formation of new condensation inside the cover 24 is suppressed, and any condensed water that has formed can be vaporized.

[0077] The processor 98 continues to drive the motor 21 at the first set rotation speed as a condensation prevention operation (step ST44). During the condensation prevention operation, when the time elapsed from the start of the condensation prevention operation to the start of the condensation prevention operation, which is a third set time that has been set in advance and stored in the memory 97 (step ST45), the processor 98 stops the pump 22 (step ST46).

[0078] Alternatively, during condensation prevention operation, the processor 98 performs the condensation determination process of the first example, and if it determines that no condensation has been detected (step ST47), it continues the condensation prevention operation until a fourth set time, which is pre-set and stored in memory 97, has elapsed. If the processor 98 does not determine that condensation has been detected until the fourth set time has elapsed, it stops the pump 22 after the fourth set time has elapsed (step ST48) (step ST46). Alternatively, during condensation prevention operation, the processor 98 performs the condensation determination process of the second example or the third example, and if it determines that no condensation has been estimated (step ST49), it continues the condensation prevention operation until a fifth set time, which is pre-set and stored in memory 97, has elapsed. If the processor 98 does not determine that condensation has been detected until the fifth set time has elapsed, it stops the pump 22 after the fifth set time has elapsed (step ST50) (step ST46). Here, the fourth and fifth setting times can be set appropriately based on the time it can be determined that condensation will not occur, the time it can be determined that any condensation that does occur can be evaporated, etc.

[0079] As in this example, the processor 98 performs condensation prevention operation processing. Note that the condensation prevention operation processing may also include control processing to further prevent the occurrence of condensation. As a specific example, as shown by the dashed arrow in Figure 9, after the start of condensation prevention operation, the processor 98 performs condensation detection processing, and if a condensation detection determination or estimated condensation detection determination is continued even after a sixth setting time shorter than the third setting time has elapsed (step ST61) (step ST62), the processor 98 performs condensation prevention operation at a rotation speed that is a predetermined fixed percentage of the first setting rotation speed, a current value, or a second setting rotation speed obtained by adding the current value (step ST63).

[0080] Then, until the condensation prevention operation is stopped in step ST45, step ST47, or step ST49 or later, the process from step ST61 onwards is repeated, and the rotation speed of the condensation prevention operation (second set rotation speed) is corrected repeatedly or a predetermined number of times by adding the rotation speed, current value, or current value at a certain rate. In this way, the condensation prevention operation process may be configured to correct the rotation speed during the condensation prevention operation. Furthermore, if the rotation speed is increased by adding a certain rate from the first set rotation speed in step ST63, the second set rotation speed immediately before stopping the condensation prevention operation may be stored in memory 97 in order to perform the next condensation prevention operation smoothly, and the set value of the corrected rotation speed (second set rotation speed) may be changed to the stored rotation speed for subsequent condensation prevention operations.

[0081] In practice, the rotational speeds of the motor 21 and pump 22 are varied to prevent condensation by generating heat from the motor 21. Therefore, the first set rotational speed and the second set rotational speed may be based on rotational speed (rotational speed of the pump 22 or operating frequency of the motor 21), current value (primary current value, DC intermediate current value, or secondary current value of the inverter unit 96), or power value (input power value (power consumption) of the inverter unit 96, output power value, or shaft power). This is because the rotational speed of the motor 21 can be controlled by varying the rotational speed, current value, or power value.

[0082] Furthermore, the motor 21 and the variable speed control equipment (inverter unit 96) do not have to be integrated with the motor 21, but may be provided separately from the motor 21 and the pump device 1. Alternatively, an electrical box (housing 51) including the variable speed control equipment may be mounted, and condensation prevention may be performed not only on the motor 21 but also on the control board inside the electrical box. In this case, as the first sensor 25, electrodes (water leakage detection device), humidity detection device, or temperature detection device mounted on the housing 51 may be used to perform condensation determination processing and condensation prevention operation. In such a configuration, it is preferable that the display on the display unit 94, including the display of information and the illumination state such as lighting and flashing of the display unit 94, be distinguishably different between normal operation and condensation prevention operation.

[0083] As described above, the pump device 1 according to this embodiment is provided with a first sensor 25 that acquires environmental information for detecting or estimating condensation, and when condensation is detected or estimated, it performs a condensation prevention operation by driving the motor 21 at a rotational speed lower than normal operation. As a result, the pump device 1 can prevent condensation by driving a general-purpose motor 21 while suppressing an increase in manufacturing costs.

[0084] It should be noted that the present invention is not limited to the embodiments described above. For example, in the above example, a first sensor 25 is provided as a detection device for detecting or estimating condensation, and an example was described in which the processor 98 detects or estimates condensation based on the environmental information detected by the first sensor 25, but the invention is not limited to this. For example, the processor 98 may have a plurality of first sensors 25 that acquire information on different environments as detection devices, and may be configured to detect or estimate condensation based on this information on different environments. For example, the first sensor 25 may have two components: a humidity detection device and a temperature detection device, and condensation may be detected or estimated based on temperature and humidity.

[0085] Furthermore, the processor 98 may also enable the communication unit 91 to function as a detection device for acquiring environmental information. Specifically, the processor 98 may control the communication unit 91 to acquire environmental information based on the location where the pump device 1 is installed from an external device 200, such as weather information such as humidity, temperature, and probability of precipitation at the installation location. This acquired weather information may be added to, or replaced with, the information acquired by the first sensor 25 to perform condensation determination processing and estimate condensation.

[0086] 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 a description equivalent to the invention described in the original claims of this application. [1] Pump and, A motor having a motor fan and a motor that drives the pump, A control unit is provided in the motor for variable speed control of the motor, It includes a detection device that detects environmental information, The control unit detects or estimates condensation from the environmental information detected by the detection device, and drives the motor by condensation prevention operation when condensation is detected or estimated. [2] The pump device according to [1], further comprising a cover that covers the motor and the control unit. [3] The pump device according to [1], wherein the detection device is a water leak detection device that directly detects the condensation. [4] The detection device is a humidity detection device, The pump device according to [1], wherein the control unit estimates condensation when the humidity detected by the detection device while the motor is stopped is higher than a first threshold value which is a preset humidity value. [5] The detection device is a temperature detection device provided inside the motor or inside the control unit, The pump device according to [1], wherein the control unit detects the temperature at first set intervals using the detection device while the motor is stopped, and estimates condensation when the temperature difference between the temperature detected by the detection device and the maximum temperature while the motor is stopped is lower than a second threshold temperature difference which is a preset temperature difference. [6] The pump device according to [1], wherein the detection device communicates with an external device and obtains weather information from the external device as information about the environment. [7] The pump device according to [1], wherein after the driven motor stops, the condensation prevention operation is not performed for a time corresponding to the motor's operating time, or for a preset second set time. [Explanation of symbols]

[0087] 1...Pump device, 21...Motor, 22...Pump, 22a...Pump casing, 22b...Impeller, 22c...Casing cover, 22d...Inlet, 22e...Outlet, 23...Control unit, 24...Cover, 24a...Top plate, 24b...Surface, 25...First sensor, 26...Second sensor, 27...Flange, 31...Motor shaft, 32...Motor casing, 32a...Motor heat dissipation fin, 32A...First frame, 32b...Mounting surface, 32B...Second frame, 32d...First insertion hole, 32j...Second insertion hole, 35...External fan, 3 6...Fan cover, 36a...Top plate, 36b...Skirt, 36c...Ventilation hole, 38...Mounting space, 51...Housing, 53...Component cover, 57...Storage device, 61...First case, 62...Second case, 71...First body, 72...First flange, 81...Second body, 81a...Heat dissipation fins, 82...Second flange, 91...Communication unit, 92...Input unit, 93...Interface, 94...Display unit, 95...Setting unit, 96...Inverter unit, 97...Memory, 98...Processor, 99...Fastening member, 162...Input unit, 200...External device.

Claims

1. Pump and A motor having a motor fan and a motor that drives the pump, A control unit is provided in the motor for variable speed control of the motor, A detection device that detects environmental information, The motor and the control unit are covered by a cover, The control unit detects or estimates condensation inside the cover from the environmental information detected by the detection device, and when it detects or estimates condensation, it drives the motor in a condensation prevention operation that drives the motor in a different operating method than normal operation. The detection device is a temperature detection device provided inside the motor or inside the control unit. The control unit detects the temperature at first set intervals using the detection device while the motor is stopped, and estimates condensation when the temperature difference between the temperature detected by the detection device and the maximum temperature while the motor is stopped is higher than a second threshold temperature difference which is a preset temperature difference.

2. The pump device according to claim 1, wherein the condensation prevention operation is operation at a lower rotational speed than the normal operation.

3. The pump device according to claim 1, wherein the detection device is a water leak detection device that directly detects the condensation.

4. The pump device according to claim 1, wherein the detection device communicates with an external device and obtains weather information from the external device as information about the environment.

5. The pump device according to claim 1, wherein, after the driven motor stops, the condensation prevention operation is not performed for a time corresponding to the motor's operating time, or for a preset second set time.

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