Diagnostic system, diagnostic method, and program

Abstract

To solve such an issue that a bearing abnormality of a motor is falsely detected as clogging of a filter other than the time when the filter is clogged.SOLUTION: A diagnosis system 100 diagnoses a fluid carrying device 60 having a rotary device, a filter 32, and a condenser 24. In the rotary device, a motor 30 drives a fan 29 for carrying fluid by rotation. The filter 32 and the condenser 24 are provided in a flow passage 61 of fluid and formed with a route through which fluid flows. An acquisition unit 41 acquires information on a load of the motor 30. A diagnosis unit 42 makes a first determination regarding maintenance of the filter 32 and the condenser 24 and a second determination regarding a malfunction of a bearing 30d on the basis of the information on the load of the motor 30 in at least two points. The diagnosis unit 42 performs a diagnosis which promotes maintenance of the filter 32 and the condenser 24 or a diagnosis which determines a malfunction of the bearing 30d.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a diagnostic system, a diagnostic method, and a program. [Background technology]

[0002] Conventionally, when a filter becomes clogged, the load on the motor increases compared to when the filter is not clogged, even at the same fan rotation speed. Therefore, clogging is detected using the deceleration rate when the fan's driving force is removed as a physical quantity related to the motor load (Patent Document 1 (JP 2022-155832 A)). Summary of the Invention [Problem to be solved by the invention]

[0003] However, with conventional detection methods, the load on the motor increases not only when the filter is clogged but also when there is an abnormality in the motor bearings, which poses a problem in that an abnormality in the motor bearings may be mistakenly detected as a clogged filter. [Means for solving the problem]

[0004] A diagnostic system according to a first aspect is a diagnostic system for diagnosing a fluid transport device having a rotating device and a structure. The rotating device uses a motor to drive a rotor that transports a fluid by rotating. The structure is provided in a fluid flow path and has a path through which the fluid passes. The diagnostic system includes an acquisition unit and a diagnosis unit. The acquisition unit acquires information related to the load on the motor. The diagnosis unit makes a first judgment related to maintenance of the structure and a second judgment related to a failure of the rotating device based on information related to the motor load at least at two or more points in time. The diagnosis unit performs a diagnosis to encourage maintenance of the structure or a diagnosis to determine a failure of the rotating device.

[0005] This diagnostic system allows accurate determination of structural maintenance and failures in rotating devices, and enables reduction in the number of diagnostic steps for fluid transport devices.

[0006] The diagnostic system of the second aspect is the system of the first aspect, wherein the information about the motor load at least at two or more points in time includes at least one of time-series information about the motor load and time-series information about the timing to prompt maintenance.

[0007] This diagnostic system uses time-series information about the load on the motor and time-series information about the timing for maintenance to be performed, making it easy to make decisions about the maintenance of structures and failures in rotating devices.

[0008] A diagnostic system according to a third aspect is the system according to the second aspect, wherein the time-series information regarding the load on the motor includes at least one of information regarding a change in the load on the motor over time and information regarding a change in the load on the motor before and after maintenance, and the time-series information regarding the timing of prompting maintenance includes information regarding an interval at which maintenance is prompted.

[0009] This diagnostic system uses information about changes in motor load over time or changes before and after maintenance, or information about intervals that prompt maintenance, making it easy to make decisions about structural maintenance and rotating device failures.

[0010] A diagnostic system according to a fourth aspect is the system according to any one of the first to third aspects, wherein the information about the load on the motor includes a degree of deceleration after the driving force of the rotating body is removed, or the load on the motor. The acquisition unit acquires the degree of deceleration as a deceleration time or a deceleration rate of the rotating body. The acquisition unit acquires the load on the motor from a current, voltage, power, or frequency of the motor.

[0011] In this diagnostic system, information regarding changes in the state values ​​related to the motor load can be used to facilitate decisions regarding maintenance of the structure and failures of the rotating equipment.

[0012] A diagnostic system according to a fifth aspect is the system according to any one of the first to fourth aspects, wherein the structure is a filter or a heat exchanger, and the maintenance is replacement of the structure or removal of deposits.

[0013] The diagnostic system allows decisions to be made regarding filter and heat exchanger maintenance.

[0014] A diagnostic system according to a sixth aspect is the system according to any one of the first to fifth aspects, wherein the first determination includes a determination regarding clogging of a structure, and the second determination includes a determination regarding an abnormality in a bearing of the rotating device.

[0015] With this diagnostic system, if a structure becomes clogged and no abnormality in the rotating device occurs, a diagnosis is performed to prompt maintenance of the structure, and if an abnormality in the rotating device occurs, a diagnosis is performed to determine that the rotating device is faulty.

[0016] A diagnostic system according to a seventh aspect is the system according to any one of the first to sixth aspects, further comprising an alarm unit. When the diagnosing unit performs a diagnosis to prompt maintenance of the structure, the alarm unit issues a notification to prompt maintenance. When information related to the load on the motor exceeds a predetermined maintenance threshold, the diagnosing unit performs a diagnosis to prompt maintenance. When the interval between notifications by the alarm unit becomes short to a predetermined level, the diagnosing unit performs a diagnosis to determine that the rotating device has a fault.

[0017] In this diagnostic system, by using the interval between notifications from the notification unit, it is possible to easily determine whether a failure has occurred in the rotating device.

[0018] A diagnostic system according to an eighth aspect is a system according to any one of the first to sixth aspects, in which the diagnostic unit performs a diagnosis to determine that the rotating device has failed if information regarding the load on the motor does not return to a predetermined value after maintenance is completed.

[0019] In this diagnostic system, by using a status value relating to the load on the motor after maintenance, it is possible to easily determine whether a fault has occurred in the rotating device.

[0020] A diagnostic system according to a ninth aspect is the system according to the eighth aspect, wherein the diagnostic unit performs a diagnosis to determine that the rotating device has failed when the amount of change in information relating to the load on the motor before and after maintenance becomes smaller than a predetermined amount.

[0021] This diagnostic system can easily determine whether a rotating device has failed by using state values ​​relating to the load on the motor before and after maintenance.

[0022] A diagnostic system of a tenth aspect is a system of any one of the first to sixth aspects, wherein the diagnostic unit performs a diagnosis to determine that the rotating device has failed if the rate of change over time of information relating to the load on the motor becomes greater than a predetermined value immediately after maintenance.

[0023] In this diagnostic system, a fault in the rotating device can be easily determined by using a state value relating to the load on the motor immediately after maintenance.

[0024] A diagnostic system of an eleventh aspect is a system of any one of the first to sixth aspects, wherein the diagnostic unit performs a diagnosis to determine that the rotating device has failed when the rate of change over time of the information regarding the motor load becomes greater than a predetermined value at a time when the information regarding the motor load does not exceed a maintenance threshold.

[0025] This diagnostic system can quickly determine if a rotating device has a fault even if the maintenance threshold has not been exceeded.

[0026] A diagnostic method according to a twelfth aspect is a diagnostic method for diagnosing a fluid transport device having a rotating device and a structure. The rotating device has a rotor that transports a fluid by rotating, driven by a motor. The structure is provided in a fluid flow path and has a path through which the fluid passes. The diagnostic method includes an acquisition step and a diagnosis step. The acquisition step acquires information related to the load of the motor. The diagnosis step makes a first judgment related to maintenance of the structure and a second judgment related to a failure of the rotating device based on information related to the load of the motor at least two or more points in time. The diagnosis step performs a diagnosis to encourage maintenance of the structure or a diagnosis to determine a failure of the rotating device.

[0027] This diagnostic method allows accurate determination of structural maintenance and failures in the rotating device, and enables reduction in the number of diagnostic steps for the fluid transport device.

[0028] A diagnostic program according to a thirteenth aspect is a diagnostic program for realizing, by a computer, a diagnostic system for diagnosing a fluid transport device having a rotating device and a structure. The rotating device has a rotor that transports a fluid by rotating, driven by a motor. The structure is provided in a fluid flow path and has a path through which the fluid passes. The computer is made to function as an acquisition means and a diagnostic means. The acquisition means acquires information related to the load of the motor. The diagnostic means makes a first judgment regarding maintenance of the structure and a second judgment regarding a failure of the rotating device based on information related to the load of the motor at least two points in time. The diagnostic means makes a diagnosis to encourage maintenance of the structure or a diagnosis to determine a failure of the rotating device.

[0029] This diagnostic program allows accurate determination of structural maintenance and failures in the rotating device, thereby reducing the number of diagnostic steps required for the fluid transport device. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 2 is a schematic diagram of an oil cooling device in the diagnostic system. [Figure 2] FIG. 2 is a partial cross-sectional view schematically showing a vertical cross section of the oil cooling device. [Figure 3] FIG. 2 is a cross-sectional view of the motor 30. [Figure 4] 10 is an enlarged view of the bearing 30d and its surroundings enclosed by a frame B. FIG. [Figure 5] FIG. 2 is a block diagram schematically illustrating a control device, and each unit and output device connected to the control device. [Figure 6] FIG. 2 is a diagram for explaining the operation of the diagnostic system. [Figure 7] 1 is a flowchart of a diagnostic system. [Figure 8] FIG. 10 is a diagram for explaining the operation of the diagnostic system of Modification 1A. [Figure 9] 10 is a flowchart of a diagnostic system according to Modification 1A. [Figure 10] 10 is a flowchart of a diagnostic system according to Modification 1B. [Figure 11] 10 is a flowchart of a diagnostic system according to modification 1C. [Figure 12] FIG. 10 is a diagram for explaining bearing loss. [Figure 13] 10 is a flowchart of a diagnostic system according to a modified example 1D. DETAILED DESCRIPTION OF THE INVENTION

[0031] First Embodiment (1) Diagnostic system configuration Hereinafter, embodiments will be described. In the drawings, the same reference numerals represent the same or corresponding parts. Dimensions in the drawings, such as length, width, thickness, and depth, may be changed from the actual scale for clarity and simplification of the drawings, and may not represent actual relative dimensions.

[0032] The diagnostic system 100 of this embodiment diagnoses a fluid transport device 70 having a rotating device and a structure. As shown in FIG. 1 , the diagnostic system 100 of this embodiment mainly has an oil cooling device 1 and a machine tool 90.

[0033] (2) Oil cooling device FIG. 1 is a schematic diagram of an oil cooling device in a diagnostic system 100 of this embodiment. The oil cooling device 1 shown in FIG. 1 is an example of a fluid cooling device that cools a fluid, and in this example, cools oil. The oil cooling device 1 shown in FIG. 1 cools hydraulic oil, lubricating oil, or cooling oil (hereinafter simply referred to as "oil") of a machine tool 90 by circulating it through an oil tank T. Specific examples of the machine tool 100 include machining centers, NC (Numerical Control) lathes, grinding machines, NC dedicated machines, and NC electric discharge machines. The oil cooling device 10 may also be a device that cools oil in machines of a different type from machine tools (such as molding machines and presses).

[0034] The oil cooling device 1 includes a refrigerant circuit RC in which a compressor 21, a condenser 24, an electronic expansion valve EV, and an evaporator 25 are connected in a ring shape, a four-way switching valve 22 that switches the refrigerant circulation direction in the refrigerant circuit RC from a forward cycle to a reverse cycle, a fan 29 that supplies air to the condenser 24, and a control device 40 that controls the refrigerant circuit RC and the four-way switching valve 22. The electronic expansion valve EV is an example of a pressure reducing mechanism. The refrigerant circuit RC has a hot gas bypass pipe L10 and a hot gas bypass valve HGB disposed in the hot gas bypass pipe L10.

[0035] Although the embodiment shown here is an oil cooling device that can switch between a forward cycle and a reverse cycle using a four-way selector valve, the cooling cycle of the oil cooling device may be a cycle that does not have a four-way selector valve.

[0036] The refrigerant circuit RC, the four-way switching valve 22, the fan 29, and the control device 40 are housed in a housing 3.

[0037] The condenser 24 is an example of a first heat exchanger, and the evaporator 25 is an example of a second heat exchanger.

[0038] The discharge side of the compressor 21 is connected to a first port 22a of a four-way switching valve 22. A second port 22b of the four-way switching valve 22 is connected to one end of a condenser 24 via a shut-off valve V1. The other end of the condenser 24 is connected to one end of an electronic expansion valve EV via a shut-off valve V2.

[0039] The other end of the electronic expansion valve EV is connected to one end 25a of the evaporator 25. The other end 25b of the evaporator 25 is connected to a third port 22c of the four-way switching valve 22. A fourth port 22d of the four-way switching valve 22 is connected to the suction side of the compressor 21 via the accumulator 23. The one end 25a of the evaporator 25 is connected to one end of the hot gas bypass pipe L10. The other end of the hot gas bypass pipe L10 is connected to a second port 2b of the four-way switching valve 22.

[0040] One end of a pipe L1 is immersed in the oil in the oil tank T, and the other end is connected to the suction port of the circulation pump P. The discharge port of the circulation pump P is connected to the inlet port 25c of the evaporator 25 via a pipe L2.

[0041] Outlet port 25d of evaporator 25 is connected to one end of pipe L3, and the other end of pipe L3 is connected to inlet port 91 of machine tool 90. Outlet port 92 of machine tool 90 and oil tank T are connected via pipe L4.

[0042] The oil tank T, the evaporator 25, the machine tool 90, and the pipes L1 to L4 are included in a circulation path through which the oil circulates.

[0043] The oil cooling system includes an oil cooling device 1 and a circulation path. In the first embodiment, the oil cooling device 1 includes a circulation pump P, but the oil cooling system may also be a system that includes a circulation pump outside the oil cooling device.

[0044] During oil cooling operation of the oil cooling device 1, high-pressure gas refrigerant discharged from the compressor 21 flows into the condenser 24 via the four-way selector valve 22, where it exchanges heat with outside air and condenses to become liquid refrigerant. The liquid refrigerant is then decompressed by the electronic expansion valve EV, flows into the evaporator 25, where it exchanges heat with the oil and evaporates to become low-pressure gas refrigerant, and returns to the suction side of the compressor 1 via the accumulator 23. This causes the oil to be cooled in the evaporator 25. During this oil cooling operation, the control device 40 controls the rotational frequency of the compressor 21 and the aperture of the electronic expansion valve EV based on the oil temperature, the room temperature, and the like. The hot gas bypass valve HGB, installed in the hot gas bypass pipe L10, adjusts the amount of high-temperature, high-pressure gas supplied to the evaporator 25 to control the cooling capacity during low loads.

[0045] 2 is a partial cross-sectional view schematically showing a vertical section of the oil cooling device. Filter 32, condenser 24, and fan 29 are arranged in casing 3 in this order from the suction port 31 side. Filter 32 may be attached to suction port 31 of casing 3 with a distance D (for example, 10 mm) from condenser 24, or may be in partial or complete contact with condenser 24 (distance D = 0 mm).

[0046] In the oil cooling device 1, the rotation of the fan 29 causes outside air to be sucked from the intake port 31 through the filter 32, and the air is supplied to the condenser 24, and then discharged from the outlet port 33.

[0047] Depending on the environment in which the oil cooling device 1 is used, air A containing foreign matter such as oil smoke (oil mist) or dust generated by the machine tool 90 may be supplied to the filter 32 or the condenser 24. When air A containing foreign matter is supplied to the filter 32 or the condenser 24, clogging of the filter 32 or the condenser 24 occurs. When clogging occurs, the oil cooling capacity of the oil cooling device 1 decreases, which may cause, for example, a sudden stop of the machine tool 90 or a decrease in machining accuracy. When the condenser 24 becomes clogged, measures such as removing the condenser 24 from the housing 3 and cleaning or replacing it are required, resulting in long periods of downtime and significant opportunity loss.

[0048] (2-1) Fluid transport device The oil cooling device 1 of this embodiment includes a fluid conveying device 60 that has a function of detecting clogging of the filter 32 or the condenser 24. The fluid conveying device 60 has a rotating device, a structure, a control device 40, and an output device 50. In other words, the fluid conveying device 60 is a device that conveys air A, which is an example of a fluid, from the suction port 31 to the outlet 33. The fluid conveying device 60 includes a fan 29, a motor 30, a filter 32, the condenser 24, the control device 40, and the output device 50.

[0049] (2-1-1) Rotating device In this embodiment, the rotating device includes a fan 29 and a motor 30. The rotating device uses the motor to drive a rotor that rotates to transport a fluid.

[0050] Fan 29 is an example of a rotating body that is driven to rotate by motor 30 to transport air A along flow path 61 inside housing 3. In this example, fan 29 is disposed midway through flow path 61, but it may also be disposed at an end of flow path 61 (for example, at outlet 33). Fluid A flowing through flow path 61 is transferred from intake port 31 to outlet 33 by the rotation of fan 29. Fan 29 rotates so that air A is sucked from intake port 32 through filter 32, and air A filtered by passing through filter 32 is supplied to condenser 24. Air A that has passed through condenser 24 by the rotation of fan 29 is discharged from outlet 33.

[0051] The flow path 61 is a passage through which the air A flows. At least a portion of the flow path 61 may be formed by a structure such as a duct arranged inside the housing 3, may be formed by an inner wall 62 inside the housing 3, or may be formed by the housing 3. In the example shown in FIG. 1 , the flow path 61 is an internal space surrounded by the inner wall 62 inside the housing 3, the inner surface 3a of the housing 3, and the oil reservoir 81.

[0052] The housing 3 has, for example, a bottom frame 80 that covers the underside of the housing 3. The bottom frame 80 has an oil reservoir 81 provided below the condenser 24 and the filter 32. The oil reservoir 81 receives and collects oil droplets from the condenser 24 and the filter 32. The oil reservoir 81 is also referred to as an oil pan. The oil reservoir 81 may be formed integrally with the bottom frame 80, or may be provided separately from the bottom frame 80.

[0053] The motor (fan motor) 30 is an electric motor that rotates the fan 29. The rotation shaft of the motor 30 is connected to the rotation center of the fan 29 directly or via a gear. The motor 30 is controlled by the control device 40. The motor 30 may be disposed inside or outside the flow path 61. By disposing the motor 30 inside the flow path 61, the motor 30 can be cooled by the air A.

[0054] Figure 3 is a cross-sectional view of the motor. Motor 30 is an inverter motor with a variable rotation speed equipped with an inverter (not shown). The rotation speed of motor 30 is controlled by a control signal output from control unit 43 (see Figure 5). Motor 30 mainly has a stator 30a, a rotor 30b, a rotating shaft 30c, two bearings 30d, and a casing 30e. Bearing 30d holds rotating shaft 30c rotatably relative to stator 30a.

[0055] 4 is an enlarged view of the area surrounding bearing 30d enclosed in frame B. Bearing 30d is a ball bearing having an outer ring 30d1, an inner ring 30d2, and balls 30d3. The outer peripheral surface of outer ring 30d1 is fitted and fixed to the inner peripheral surface of stator 134a, and the inner peripheral surface of inner ring 30d2 is fitted and fixed to the outer peripheral surface of rotating shaft 30c. Bearing 30d is a sealed bearing filled with lubricant 30d5 such as grease.

[0056] Two bearings 30d support the rotating shaft 30c of the motor 30. The two bearings 30d are arranged side by side on the inner periphery of the stator 30a with a predetermined gap between them in the direction in which the rotation axis O extends.

[0057] (2-1-2) Structure In this embodiment, the structure includes a filter 32 and a condenser 24. The structure is provided in a fluid flow path 61, and a path through which the fluid passes is formed.

[0058] The filter 32 is an example of a structure provided in the flow path 61 and having a path through which the air A passes. The filter 32 is a structure through which the air A passes and filters the air A. The filter 32 may be provided at the end of the flow path 61 (for example, at the open end of the flow path 61, more specifically, at the intake port 31), or may be provided midway through the flow path 61 (for example, inside a duct that forms the flow path 61). For example, when the filter 32 is formed of a nonwoven fabric, the gaps between the fibers of the nonwoven fabric correspond to the passages through which the air A passes.

[0059] The condenser 24 is an example of a structure provided in the flow path 61 and having a path through which the air A passes. The condenser 24 is a structure through which the air A passes, and is provided midway along the flow path 61. The condenser 24 is a heat exchanger that liquefies a high-pressure, high-temperature gas refrigerant by exchanging heat with the air A. In the example shown in FIG. 1 , the condenser 24 is disposed between the filter 32 and the fan 29. The gaps between the multiple fins of the condenser 24 correspond to the paths through which the air A passes.

[0060] (2-1-3) Control device FIG. 5 is a block diagram that schematically shows the control device 40, as well as the components and output device 50 connected to the control device 40. The control device 40 is realized by a computer. The control device 40 is, for example, a control unit that includes a processor such as a CPU (Central Processing Unit) and a memory. The functions of the control device 40 are realized by the processor operating according to a program stored in the memory. The functions of the control device 40 may also be realized by an FPGA (Field Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit).

[0061] The control device 40 includes an acquisition unit 41 , a diagnosis unit 42 , and a control unit 43 .

[0062] The acquisition unit 41 acquires information related to the load on the motor 30. The information related to the load on the motor 30 includes at least one of time-series information related to the load on the motor 30 and time-series information related to the timing for prompting maintenance. The time-series information related to the load on the motor 30 includes at least one of information related to the change over time in the load on the motor 30 and information related to the change in the load on the motor 30 before and after maintenance. The time-series information related to the timing for prompting maintenance includes information related to the interval at which maintenance is prompted.

[0063] The diagnosing unit 42 makes a first determination regarding maintenance of the filter 32 or the condenser 24 and a second determination regarding a failure of the bearing 30d of the motor 30 based on information regarding the load of the motor 30 at least at two or more points in time.

[0064] Furthermore, the diagnosing unit 42 performs a diagnosis to prompt maintenance of the filter 32 or the condenser 24, or a diagnosis to determine that the bearing 30d has a fault. The diagnosing unit 42 performs a diagnosis to prompt maintenance when information related to the load on the motor 30 exceeds a predetermined clogging determination threshold (maintenance threshold) Th. The diagnosing unit 42 performs a diagnosis to determine that the bearing 30d has a fault when the interval at which the notification unit 51 of the output device 50 issues a notification becomes short to a predetermined level.

[0065] The control unit 43 controls the fan 29 , and more specifically, the motor 30 that rotates the fan 29 .

[0066] 2, the control device 40 further includes a drive circuit 45 that drives the motor 30 by switching a plurality of semiconductor switching elements. The drive circuit 45 supplies a drive current to the motor 30, and the motor 30 rotates the fan 29 when the drive current is supplied from the drive circuit 45. The drive circuit 45 is, for example, an inverter circuit that converts direct current from a direct current source into alternating current to be supplied to the motor 30.

[0067] Heat from the drive circuit 45 is transferred to the heat sink 46. By arranging the heat sink 46 inside the flow path 61, the heat sink 46 is cooled by the air A, improving the heat dissipation effect of the heat sink 46 on the drive circuit 45. In the example shown in FIG. 1 , the control device 40 is separated from the flow path 61 by the inner wall 62, but the control device 40 may also be arranged inside the flow path 61. The drive circuit 45 may also be arranged in a location separate from the control device 40.

[0068] The control device 40 is an example of a measurement unit that measures the degree of deceleration (hereinafter also referred to as deceleration degree G) after the driving force of the fan 29 is removed, and for example, measures the degree of deceleration G of the fan 29 after the drive circuit 45 is stopped as information related to the load on the motor 30. More specifically, the control device 40 may measure the degree of deceleration G of the fan 29 after the supply of drive current (e.g., three-phase AC drive current if the motor 30 is a three-phase motor) from the drive circuit 45 to the motor 30 is stopped. In this embodiment, the acquisition unit 41 of the control device 40 acquires the degree of deceleration G as the deceleration time of the fan 29, but may also acquire it as the deceleration rate of the fan 29.

[0069] The control device 40 may regeneratively control the motor 30 while the fan 29 is decelerating after the driving force of the fan 29 is removed, and measure the deceleration degree G of the fan 29 while the motor 30 is being regeneratively controlled. If the regenerative control of the motor 30 is being performed while the supply of driving current from the drive circuit 45 to the motor 30 is stopped, a regenerative current flows from the motor 30 to the drive circuit 45. Alternatively, the control device 40 may control the torque of the motor 30 while the fan 29 is decelerating after the driving force of the fan 29 is removed, and measure the deceleration degree G of the fan 29 while controlling the torque of the motor 30.

[0070] When the driving force of the fan 29 is removed (this may be an idling state (free-running state) or a stopping operation including the above-mentioned regenerative control or torque control state), the fan 29 tries to continue rotating by inertia. However, since a load torque is generated in the fan 29 and the motor 30, the rotation of the fan 29 and the motor 30 is decelerated. The load torque T at this time is T=(Ps+Pv)×Q / N Ps: static pressure [Pa] Pv: Dynamic pressure (Pa) Q: Air volume [m 3 / sec] N: Rotation speed of the fan 29 or motor 30 [rpm] It is expressed as:

[0071] When the filter 32 or the condenser 24 becomes clogged, the static pressure Ps increases, and the pressure loss in the flow path 61 increases. When compared at the same rotation speed, in a fan having a characteristic in which the load torque increases as the pressure loss in the flow path 61 increases, the time until the rotation of the fan 29 stops becomes shorter. In other words, the deceleration rate of the fan 29 increases. An example of a fan having this characteristic is an axial flow fan such as a propeller fan.

[0072] Taking note of such characteristics, the diagnosing unit 42 in the control device 40 determines whether the deceleration rate G (pressure loss index value) measured by the measuring unit 42 is equal to the clogging determination threshold value Th. When the control device 40 determines that the measured deceleration rate G is equal to the clogging determination threshold value Th, it determines that the pressure loss in the flow path 61 has increased compared to a reference value, and causes the output device 50 to output information indicating the increase in pressure loss in the flow path 61. The control device 40 also compares the maintenance interval, and causes the output device 50 to output the diagnosis result of the fluid transport device 60 performed by the diagnosing unit 42.

[0073] In this way, by executing the diagnostic method for the fluid transport device 60, it becomes possible to detect a clogged state, and further, it is possible to diagnose whether the detected clogged state is the occurrence of an abnormality in the bearing 30d, or the occurrence of clogged filter 32 or condenser 24.

[0074] After detecting a clogging state, it becomes possible to diagnose whether the detected clogging state is an abnormality in the bearing 30d or clogging in the filter 32 or the condenser 24. This makes it easier to perform maintenance work on the filter 32 or the condenser 24, for example, and can suppress increases in labor and costs for management and servicing.

[0075] Furthermore, after detecting a clogged state, it becomes possible to diagnose whether the detected clogged state is an abnormality in the bearing 30d or a clog in the filter 32 or the condenser 24, so that preventive measures such as cleaning or replacing the filter 32 or the condenser 24 can be taken before a problem such as a decrease in the oil cooling capacity of the oil cooling device 1 occurs.

[0076] The control device 40 measures the deceleration magnitude G with the driving force of the fan 29 removed, and therefore the influence of factors that cause electrical measurement errors can be reduced.

[0077] (2-1-4) Output device The output device 50 has a notification unit 51 and a display unit 52. The output device 50 is an example of an output unit that outputs information indicating an increase in pressure loss in the flow path 61 (pressure loss increase information) when the deceleration rate G measured by the control device 40 increases above a reference value and becomes equal to the clogging determination threshold value Th. The pressure loss increase information is a type of pressure loss information that indicates the state of pressure loss in the flow path 71. In other words, the pressure loss increase information is information that indicates a clogging state. The output device 50 also outputs the diagnosis result obtained by the diagnosis unit 42 of the control device 40.

[0078] The output device 50 outputs the pressure drop increase information and the diagnosis result to the outside of the fluid transport device 60, for example, by sound, light, display, communication, or any combination thereof. Specific examples of the output device 50 include a speaker, a lamp, a display, a communication device, or a combination thereof.

[0079] In this embodiment, when the diagnosing unit 42 performs a diagnosis to prompt maintenance of the filter 32 or the condenser 24, the notifying unit 51 issues a notification to prompt maintenance. In other words, when the pressure loss index value (deceleration rate G) increases from a reference value and becomes equal to the clogging determination threshold value Th, the notifying unit 51 outputs pressure loss increase information by notifying that a clogging state has been detected. Also, in this embodiment, the display unit 52 displays the diagnosis result by the diagnosing unit 42.

[0080] (3) Overall operation of the diagnostic system 6 is a diagram for explaining the operation of the diagnostic system 100. In the diagnostic system 100 of this embodiment, the cause of a failure is determined based on the maintenance interval (hereinafter also referred to as the maintenance interval).

[0081] The vertical axis of FIG. 6 represents the pressure loss index value, and the horizontal axis represents the driving time of the fluid transport device 60. The pressure loss index value is information related to the load on the motor 30. In this embodiment, the pressure loss index value is the deceleration rate G after the driving force of the fan 29 is removed, and is the deceleration time of the fan 29. A large pressure loss index value means that the deceleration time of the fan 29 is short. A small pressure loss index value means that the deceleration time of the fan 29 is long.

[0082] The clogging determination threshold value Th is a value for determining whether or not a clogging state exists.

[0083] The maintenance interval refers to the time from when maintenance of the filter 32 is performed until clogging is detected.

[0084] The standard maintenance interval (hereinafter also referred to as the standard maintenance interval) a1 refers to the maintenance interval under normal conditions. Under normal conditions, the bearing 30d is in a normal state. In other words, the standard maintenance interval a1 refers to the amount of change in the driving time of the fluid transport device 60 until the pressure loss index value changes from the reference value t1 to the clogging determination threshold value Th when the bearing 30d is in a normal state.

[0085] If the bearing 30d is normal, the clogging determination threshold Th correctly detects the clogging state of the filter 32. However, if an abnormality occurs in the bearing 30d and the load on the motor 30 increases, the pressure loss index value differs from the actual clogging level, and the filter 32 is erroneously detected as being clogged even when it is not clogged.

[0086] When an abnormality occurs in the bearing 30d, the maintenance interval a2, which is the amount of change in the operating time of the fluid transport device 60 from when maintenance of the filter 32 is performed until clogging is detected, becomes shorter than the standard maintenance interval a1. In the diagnosis system 100 of this embodiment, the cause of the abnormality is determined from the difference in the maintenance interval. When the maintenance interval (clogging alarm interval) suddenly becomes shorter than the standard maintenance interval, the bearing 30d is diagnosed as abnormal.

[0087] A flow chart of the diagnostic system 100 is shown in FIG.

[0088] In step S1, the acquisition unit 41 acquires a pressure loss index value. In this embodiment, the deceleration time of the fan 29 is acquired as the pressure loss index value. As shown in FIG. 6, the pressure loss index value becomes larger than the reference value t1 as the driving time of the fluid transporting device 60 increases. For example, the reference value t1 of the pressure loss index value (deceleration time of the fan 29) is 10 seconds, and the pressure loss index value acquired in step S1 is 5 seconds.

[0089] In step S2, the diagnosis unit 42 determines whether the pressure loss index value acquired in step S1 is equal to the clogging determination threshold value Th.

[0090] If the pressure loss index value is equal to the clogging determination threshold Th (Yes in step S2), the process proceeds to step S3. In this embodiment, the clogging determination threshold Th is 5 seconds, but is not limited to this. Since the pressure loss index value acquired in step S1 is equal to the clogging determination threshold Th, the process proceeds to step S3.

[0091] If the pressure loss index value is not equal to the clogging determination threshold value Th (No in step S2), the process returns to step S1. In other words, if the pressure loss index value has not increased to the point where it is equal to the clogging determination threshold value Th, the process returns to step S1.

[0092] In step S3, the notification unit 51 notifies that a clogging state has been detected.

[0093] In step S4, the acquisition unit 41 acquires a standard maintenance interval a1. In this embodiment, the standard maintenance interval a1 is the amount of change in the operating time of the fluid transporting device 60 until the pressure loss index value changes from the standard value t1 of 10 seconds to the clogging determination threshold value Th of 5 seconds. For example, the standard maintenance interval a1 is 30 days.

[0094] In step S5, maintenance is performed on the filter 32. In this embodiment, the maintenance involves cleaning the filter 32.

[0095] In step S6, the acquisition unit 41 acquires a pressure loss index value. In this embodiment, as shown in FIG. 6, cleaning the filter 32 in step S5 returns the deceleration time of the fan 29 from 5 seconds, which is the clogging determination threshold value Th, to the reference value of 10 seconds. Thereafter, as time passes, the pressure loss index value becomes larger than the reference value t1. For example, the reference value t1 of the pressure loss index value (deceleration time of the fan 29) is 10 seconds, and the pressure loss index value acquired in step S6 is 5 seconds.

[0096] In step S7, the diagnosis unit 42 determines whether the pressure loss index value acquired in step S6 is equal to the clogging determination threshold value Th. In other words, the diagnosis unit 42 determines that the fan 29 is in a clogging state when the deceleration time of the fan 29 is equal to the clogging determination threshold value Th.

[0097] If the pressure loss index value is equal to the clogging determination threshold Th (Yes in step S7), proceed to step S8. Since the clogging determination threshold Th is 5 seconds and the pressure loss index value acquired in step S6 is equal to the clogging determination threshold Th, proceed to step S8. If the pressure loss index value is not equal to the clogging determination threshold Th (No in step S7), return to step S6.

[0098] In step S8, the notification unit 51 notifies that a clogging state has been detected.

[0099] In step S9, the acquisition unit 41 acquires a post-maintenance maintenance interval a2 (hereinafter also referred to as the post-maintenance maintenance interval). In this embodiment, the post-maintenance maintenance interval a2 refers to the amount of change in the operating time of the fluid transport device 60 from when maintenance of the filter 32 is performed in step S5 until a clogged state is detected in step S7. For example, the post-maintenance maintenance interval a2 is 20 days.

[0100] In step S10, the diagnosis unit 42 determines whether the difference between the reference maintenance interval a1 and the maintenance interval a2 after maintenance is greater than a first determination value.

[0101] If the difference between the standard maintenance interval a1 and the post-maintenance maintenance interval a2 is greater than the first judgment value (Yes in step S10), proceed to step S11. In this embodiment, the first judgment value is 5 days, but is not limited to this. The difference between the standard maintenance interval a1 and the post-maintenance maintenance interval a2 is 10 days, which is greater than the first judgment value, so proceed to step S11. If the difference between the standard maintenance interval a1 and the post-maintenance maintenance interval a2 is equal to or less than the first judgment value (No in step S10), proceed to step S12.

[0102] In step S11, the diagnosing unit 42 diagnoses that the bearing 30d of the motor (fan motor) 30 is abnormal.

[0103] In step S12, the diagnosing unit 42 diagnoses that the filter 32 is clogged.

[0104] In step S13, the output device 50 outputs the diagnosis result of the diagnosing unit 42. In this embodiment, the display unit 52 displays the diagnosis result (step S11) that the clogging state detected in step S7 is due to a bearing abnormality in the fan motor.

[0105] (4) Features (4-1) The diagnostic system 100 according to this embodiment is a diagnostic system that diagnoses a fluid transport device 60 that includes a rotating device, a filter 32, and a condenser 24. The rotating device uses a motor 30 to drive a fan 29 that rotates to transport a fluid. The filter 32 and the condenser 24 are provided in a fluid flow path 61, forming a path through which the fluid passes. The diagnostic system 100 includes an acquisition unit 41 and a diagnosis unit 42. The acquisition unit 41 acquires information related to the load on the motor 30. The diagnosis unit 42 makes a first determination regarding maintenance of the filter 32 and the condenser 24 and a second determination regarding a failure of the bearing 30d based on information related to the load on the motor 30 at least at two or more points in time. The diagnosis unit 42 performs a diagnosis that prompts maintenance of the filter 32 and the condenser 24, or a diagnosis that determines a failure of the bearing 30d.

[0106] Conventionally, when a filter becomes clogged, the fan motor load increases from when it is not clogged, even at the same fan rotation speed. Therefore, clogging is detected using the degree of deceleration when the fan's driving force is removed as a physical quantity correlated with this fan motor load.

[0107] However, the fan motor load increases not only when the filter is clogged but also when there is an abnormality in the motor bearings, so conventional technology may erroneously detect an abnormality in the motor bearings as a clogged filter.

[0108] In the diagnostic system 100 according to this embodiment, after the degree of clogging of the filter 32 calculated from the load information of the fan motor 30 reaches the abnormality threshold (clogging determination threshold) Th and clogging of the filter 32 is detected, it is determined whether the cause of the detection is an abnormality in the bearing 30d.

[0109] After issuing a clogging alarm based on the load information obtained from the fan motor 30, maintenance is performed, and the pressure loss included in the load information of the fan motor 30 becomes zero, but the abnormality in the bearing 30d does not become zero.

[0110] The abnormal change in the bearing 30d is extracted from the maintenance and the load information that changes as a result of the maintenance, and it is determined whether the bearing 30d is abnormal. As a result of the maintenance, the information regarding the maintenance interval of the filter 32 is used as information for extracting the remaining abnormal change in the bearing 30d, and the cause of the failure is determined.

[0111] This diagnostic system 100 can accurately determine whether maintenance of the filter 32 and the condenser 24 and failure of the bearing 30d are performed, thereby reducing the number of diagnostic steps for the fluid transporting device 60. Furthermore, this diagnostic system 100 can accurately detect the cause of the failure and take the correct measures, thereby reducing the number of repair steps for the fluid transporting device 60.

[0112] (4-2) In the diagnostic system 100 according to this embodiment, the information relating to the load on the motor 30 at least at two or more points in time includes at least one of time-series information relating to the load on the motor 30 and time-series information relating to the timing for prompting maintenance.

[0113] This diagnostic system 100 can easily make decisions regarding maintenance of the filter 32 and condenser 24 and failure of the bearing 30d by using time-series information regarding the load on the motor 30 and time-series information regarding the timing of prompting maintenance.

[0114] (4-3) In the diagnostic system 100 according to this embodiment, the time-series information regarding the load on the motor 30 includes at least one of information regarding a change over time in the load on the motor 30 and information regarding a change in the load on the motor 30 before and after maintenance. The time-series information regarding the timing to prompt for maintenance includes information regarding the interval at which to prompt for maintenance.

[0115] This diagnostic system 100 uses information regarding changes in the load on the motor 30 over time or changes before and after maintenance, or information regarding the interval at which maintenance is required, to easily make judgments regarding maintenance of the filter 32 and condenser 24 and failure of the bearing 30d.

[0116] (4-4) In the diagnostic system 100 according to this embodiment, the information relating to the load on the motor 30 includes the degree of deceleration after the driving force of the fan 29 is removed. The acquisition unit 41 acquires the degree of deceleration as the deceleration time or deceleration rate of the fan 29.

[0117] In this diagnostic system 100, by using information about changes in the status value related to the load on the motor 30, it is possible to easily make decisions regarding maintenance of the filter 32 and the condenser 24 and failure of the bearing 30d.

[0118] (4-5) In the diagnostic system 100 according to this embodiment, the first determination includes a determination regarding clogging of the filter 32 and the condenser 24. The second determination includes a determination regarding an abnormality in the bearing 30d of the rotating device.

[0119] In this diagnostic system 100, when the filter 32 and the condenser 24 become clogged, if there is no abnormality in the bearing 30d, a diagnosis is performed to prompt maintenance of the filter 32 and the condenser 24, and if there is an abnormality in the bearing 30d, a diagnosis is performed to determine that the bearing 30d is faulty.

[0120] (4-6) The diagnostic system 100 according to this embodiment further includes a notification unit 51. When the diagnostic unit 42 performs a diagnosis to prompt maintenance of the filter 32 and the condenser 24, the notification unit 51 issues a notification to prompt the maintenance. When information related to the load on the motor 30 exceeds a predetermined clogging determination threshold Th, the diagnostic unit 42 performs a diagnosis to prompt the maintenance. When the interval between notifications by the notification unit 51 becomes short to a predetermined level, the diagnostic unit 42 performs a diagnosis to determine that the bearing 30d has a fault.

[0121] In this diagnostic system 100, by using the notification interval of the notification unit 51, it is possible to easily determine whether or not there is a malfunction in the bearing 30d.

[0122] (4-7) The diagnostic method according to this embodiment is a diagnostic method for diagnosing a fluid transport device 60 having a rotating device, a filter 32, and a condenser 24. The rotating device uses a motor 30 to drive a fan 20 that rotates to transport a fluid. The filter 32 and the condenser 24 are provided in a fluid flow path 61, forming a path through which the fluid passes. The diagnostic method includes an acquisition step and a diagnosis step. The acquisition step acquires information related to the load on the motor 30. The diagnosis step makes a first judgment regarding maintenance of the filter 32 and the condenser 24 and a second judgment regarding a failure of the bearing 30d, based on information related to the load on the motor 30 at least at two or more points in time. The diagnosis step performs a diagnosis to encourage maintenance of the filter 32 and the condenser 24, or a diagnosis to determine a failure of the bearing 30d.

[0123] This diagnostic method allows accurate determination of maintenance of the filter 32 and the condenser 24 and failure of the bearing 30d, and enables reduction in the number of diagnostic steps for the fluid transport device 60.

[0124] (4-8) The diagnostic program according to this embodiment is a diagnostic program for implementing, by a computer, a diagnostic system for diagnosing a fluid transport device 60 having a rotating device, a filter 32, and a condenser 24. The rotating device uses a motor 30 to drive a fan 29 that rotates to transport a fluid. The filter 32 and the condenser 24 are provided in a fluid flow path 61, forming a path through which the fluid passes. The computer functions as an acquisition means and a diagnostic means. The acquisition means acquires information related to the load on the motor 30. The diagnostic means makes a first determination regarding maintenance of the filter 32 and the condenser 24 and a second determination regarding a failure of the bearing 30d based on information related to the load on the motor 30 at least at two or more points in time. The diagnostic means performs a diagnosis to recommend maintenance of the filter 32 and the condenser 24, or a diagnosis to determine a failure of the bearing 30d.

[0125] This diagnostic program allows accurate determination of maintenance of the filter 32 and the condenser 24 and failure of the bearing 30d, and enables reduction in the number of diagnostic steps for the fluid transport device 60.

[0126] (5) Variations (5-1) Variation 1A In the diagnostic system 100 shown in FIG. 1, the diagnostic unit 42 may perform a diagnosis to determine that the bearing 30d is faulty if information regarding the load on the motor 30 does not return to a predetermined value after maintenance of the filter 32 is completed.

[0127] FIG. 8 is a diagram for explaining the operation of the diagnostic system of the modification 1A.

[0128] 8, the vertical axis represents the pressure loss index value, and the horizontal axis represents the driving time of the fluid transporting device 60. The pressure loss index value is information relating to the load on the motor 30. In Modification 1A, the pressure loss index value is the deceleration rate G after the driving force of the fan 29 is removed, and is the deceleration time of the fan 29.

[0129] The initial value t11 of the pressure loss index value (deceleration rate G) refers to the pressure loss index value in a state where the filter 32 is not clogged and where no abnormality occurs in the bearing 30d.

[0130] The clogging determination threshold value Th is a value for determining whether or not a clogging state exists.

[0131] If the bearing 30d is normal, the pressure loss index value returns to the initial value t11 after maintenance of the filter 32. However, if an abnormality occurs in the bearing 30d and the load on the motor 30 increases, the influence of this increase will not be reduced to zero even if maintenance is performed on the filter 32, and the pressure loss index value will not return to the initial value t11.

[0132] In Modification 1A, the cause of the abnormality is determined from the difference d1 between the initial value t11 and the pressure loss index value t12 after maintenance of the filter 32. If the pressure loss index value does not recover even after maintenance of the filter 32, it is determined that an abnormality has occurred in the bearing 30d.

[0133] A flowchart of the diagnostic system of the modified example 1A is shown in FIG.

[0134] In step S21, the acquisition unit 41 acquires a pressure loss index value. In modification 1A, the deceleration time of the fan 29 is acquired as the pressure loss index value. As shown in FIG. 8, the pressure loss index value becomes larger than the initial value t11 as the driving time of the fluid transporting device 60 increases. For example, the initial value t11 of the pressure loss index value (deceleration time of the fan 29) is 10 seconds, and the pressure loss index value acquired in step S21 is 5 seconds.

[0135] In step S22, the diagnosing unit 42 determines whether the pressure loss index value acquired in step S21 is equal to the clogging determination threshold value Th.

[0136] If the pressure loss index value is equal to the clogging determination threshold Th (Yes in step S22), proceed to step S23. In modification 1A, if the clogging determination threshold Th is 5 seconds, the pressure loss index value acquired in step S21 is equal to the clogging determination threshold Th, so proceed to step S23. If the pressure loss index value is not equal to the clogging determination threshold Th (No in step S22), return to step S21.

[0137] In step S23, the notification unit 51 notifies that a clogging state has been detected.

[0138] In step S24, maintenance is performed on the filter 32. In modification 1A, the maintenance is performed by cleaning the filter 32.

[0139] In step S25, the diagnosis unit 42 determines whether the difference d1 between the pressure loss index value t12 after the maintenance of the filter 32 in step S24 and the initial value t11 is greater than a second determination value. By cleaning the filter 32 in step S24, the pressure loss index value becomes smaller than the clogging determination threshold value Th.

[0140] If the difference between the pressure loss index value s12 after maintenance of the filter 32 and the initial value s11 is greater than the second judgment value (Yes in step S25), the process proceeds to step S26. In modification 1A, the second judgment value is 1 second, but is not limited to this. In modification 1A, the pressure loss index value t12 after maintenance of the filter 32 in step S24 is 8 seconds. Since the initial value t11 is 10 seconds, the difference d1 between the pressure loss index value t12 after maintenance of the filter 32 and the initial value t11 is 2 seconds. Therefore, the difference d1 between the pressure loss index value t12 after maintenance of the filter 32 and the initial value t11 is greater than the second judgment value, and the process proceeds to step S26.

[0141] In step S26, the diagnosing unit 42 diagnoses that the bearing 30d of the fan motor 30 is abnormal.

[0142] If the difference d1 between the pressure loss index value t12 after maintenance of the filter 32 and the initial value t11 is equal to or less than the second determination value (No in step S25), the process proceeds to step S27.

[0143] In step S27, the diagnosing unit 42 diagnoses that the bearing 30d of the fan motor 30 is normal. In other words, in step S27, the diagnosis unit 42 diagnoses that the clogged state detected in step S22 is due to clogging of the filter 32, rather than an abnormality in the bearing 30d of the fan motor 30.

[0144] In step S28, the output device 50 outputs the diagnosis result of the control device 40. In modification 1A, the display unit 52 displays the diagnosis result (step S26) that the clogging state detected in step S22 is due to an abnormality in the bearing 30d of the fan motor 30.

[0145] In Modification 1A, as a result of performing maintenance on the filter 32, information on the degree of clogging of the filter 32 after maintenance is used to extract the change in the remaining abnormality in the bearing 30d, and the cause of the failure is determined.

[0146] In the diagnostic system of the modification 1A, by using the state value relating to the load on the motor 30 after maintenance of the filter 32, it is possible to easily determine whether or not the bearing 30d has a failure.

[0147] (5-2) Variation 1B In the diagnostic system 100 shown in FIG. 1, the diagnostic unit 42 may perform a diagnosis to determine that the bearing 30d is faulty when the amount of change in information regarding the load on the motor 30 before and after maintenance of the filter 32 becomes smaller than a predetermined amount.

[0148] If the bearing 30d is normal, the pressure loss index value returns to the initial value t11 after maintenance of the filter 32. However, if an abnormality occurs in the bearing 30d and the load on the motor 30 increases, the influence of this increase will not be reduced to zero even if maintenance is performed on the filter 32, and the pressure loss index value will not return to the initial value t11.

[0149] In Modification 1B, the cause of the abnormality is determined from the difference d2 (see FIG. 8) between the pressure loss index value t12 after maintenance of the filter 32 and the clogging determination threshold value Th. If the pressure loss index value does not recover even after maintenance of the filter 32, it is determined that there is an abnormality in the bearing 30d.

[0150] A flowchart of the diagnostic system of the modified example 1B is shown in Fig. 10. The difference between the flowchart shown in Fig. 10 and the flowchart shown in Fig. 9 is that the flowchart in Fig. 10 includes step S250 instead of step S25.

[0151] In step S250, if it is determined that the difference d2 between the clogging determination threshold Th and the post-maintenance pressure loss index value t12 is smaller than the third determination value (Yes in step S250), the process proceeds to step S26. In modification 1B, the third determination value is 4 seconds, but this is not limited to this. Also, the clogging determination threshold Th is 5 seconds, and the post-maintenance pressure loss index value t12 is 8 seconds. In modification 1B, the difference d2 between the clogging determination threshold Th and the post-maintenance pressure loss index value t12 is 3 seconds. Therefore, the difference d2 between the clogging determination threshold Th and the post-maintenance pressure loss index value t12 is smaller than the third determination value, and the process proceeds to step S26.

[0152] In step S250, if it is determined that the difference d2 between the clogging determination threshold Th and the post-maintenance pressure loss index value t12 is equal to or greater than the third determination value (No in step S250), the process proceeds to step S27.

[0153] In Modification 1B, as a result of performing maintenance on the filter 32, information on the change in the degree of clogging before and after maintenance is used to extract the change in the remaining abnormality in the bearing 30d, and the cause of the failure is determined.

[0154] In the diagnostic system of the modification 1B, by using the state values ​​relating to the load on the motor 30 before and after maintenance of the filter 32, it is possible to easily determine whether or not there is a failure in the bearing 30d.

[0155] (5-3) Variation 1C In the diagnostic system 100 shown in FIG. 1, the diagnostic unit 42 may perform a diagnosis to determine that the bearing 30d is faulty if the rate of change over time of the pressure loss index value, which is information about the load on the motor 30, becomes greater than a predetermined value immediately after maintenance of the filter 32.

[0156] When an abnormality occurs in the bearing 30d, the rate of change over time b2 of the pressure loss index value after maintenance of the filter 32 becomes larger than the rate of change over time b1 of the pressure loss index value when the bearing 30d is normal (see FIG. 6). In Modification 1C, the cause of the abnormality is determined from the difference in the rate of change over time of the pressure loss index value.

[0157] The reference rate of change over time b1 refers to the rate of change over time of the pressure loss index value when the bearing 30d is normal, and is, for example, 0.5 W per day of driving time of the fluid transporting device 60 (0.5 W / day).

[0158] The rate of change over time b2 after maintenance of the filter 32 refers to the rate of change over time of the pressure loss index value after maintenance of the filter 32 is performed, and for example, if an abnormality occurs in the bearing 30d, the operating time of the fluid transport device 60 is 5W per day (5W / day).

[0159] A flowchart of the diagnostic system of Modification 1C is shown in Fig. 11. The differences between the flowchart shown in Fig. 11 and the flowchart shown in Fig. 7 are that the flowchart in Fig. 11 has step S40 instead of step S4, step S90 instead of step S9, and step S100 instead of step S10.

[0160] In step S40, the acquisition unit 41 acquires the reference rate of change over time b1.

[0161] In step S90, the acquisition unit 41 acquires the rate of change over time b2 after maintenance.

[0162] In step S100, the diagnosis unit 42 determines whether the post-maintenance time-dependent change rate b2 is greater than the reference time-dependent change rate b1. If the post-maintenance time-dependent change rate b2 is greater than the reference time-dependent change rate b1 (Yes in step S100), the process proceeds to step S11. If the rate of change over time b2 after maintenance is equal to or less than the reference rate of change over time b1 (No in step S100), the process proceeds to step S12.

[0163] 12 is a diagram for explaining bearing loss. The vertical axis of Fig. 12 represents the pressure loss index value, and the horizontal axis represents the driving time of the fluid transporting device 60. The pressure loss index value is information relating to the load on the motor 30.

[0164] The first maintenance interval a11 refers to the amount of change in the operating time of the fluid transporting device 60 from when the pressure loss index value reaches the reference value t1 until clogging is detected. When the pressure loss index value reaches the reference value t1, the bearing 30d is normal. During the first maintenance interval a11, an abnormality occurs in the bearing 30d between when the pressure loss index value reaches the reference value t1 and when the clogging determination threshold value Th.

[0165] The second maintenance interval a12 refers to the amount of change in the driving time of the fluid transporting device 60 from when the first maintenance of the filter 32 is performed after the occurrence of an abnormality in the bearing 30d until clogging is detected. The third maintenance interval a13 refers to the amount of change in the driving time of the fluid transporting device 60 from when the second maintenance of the filter 32 is performed after the occurrence of an abnormality in the bearing 30d until clogging is detected.

[0166] If the bearing 30d is normal, the clogging state of the filter 32 is correctly detected using the clogging determination threshold Th. However, if an abnormality occurs in the bearing 30d and the load on the motor 30 increases, the pressure loss index value differs from the actual clogging level, resulting in a false detection that the filter 32 is clogged even though it is not. In other words, if an abnormality occurs in the bearing 30d, the bearing loss is included in the pressure loss index value. For example, if the bearing 30d is normal, the pressure loss index value after performing maintenance on the filter 32 returns to the reference value t1 (see FIG. 6). However, as shown in FIG. 12, if an abnormality occurs in the bearing 30d, the bearing loss increases with the operating time of the fan 29 (the driving time of the fluid transport device 60). Therefore, the relationship between the reference value t1, the pressure loss index value t2 after the first maintenance, and the pressure loss index value t3 after the second maintenance is as follows: <t2<t3となる。

[0167] 12, the second maintenance interval a12 is shorter than the first maintenance interval a11, and the third maintenance interval a13 is shorter than the second maintenance interval a12. Therefore, the cause of the failure may be determined using information related to the maintenance cycle of the filter 32 as information for extracting changes in the remaining abnormality of the bearing 30d as a result of performing maintenance on the filter 32.

[0168] Also, as shown in FIG. 12, since the bearing loss increases with the operating time of the fan 29, even if the clogging degree increases constantly, due to the addition of this bearing loss (change over time), in the first maintenance period a11, the change rate over time b11 after an abnormality occurs in the bearing 30d, the change rate over time b12 in the second maintenance interval a12, and the change rate over time b13 in the third maintenance interval a13 have a relationship of b11 < b12 < b13. Also, the change rates over time b11 to b13 are larger than the reference change rate over time b1 (see FIG. 6).

[0169] In the diagnostic system of Modification 1C, by using the state value regarding the load of the motor 30 immediately after maintenance, it is possible to easily perform a failure determination of the bearing 30d.

[0170] (5-4) Modification 1D In the diagnostic system 100 shown in FIG. 1, the diagnostic unit 42 may perform a diagnosis for making a failure determination of the bearing 30d when the change rate over time of the information regarding the load of the motor 30 becomes larger than a predetermined value at a point when the information regarding the load of the motor 30 does not exceed the maintenance threshold value.

[0171] The flowchart of the diagnostic system of Modification 1D is shown in FIG. 13.

[0172] In the flowchart of FIG. 13, the reference maintenance interval in step S35 is obtained in the same manner as step S4 in FIG. 7 of the present embodiment, and the post-maintenance interval is obtained in the same manner as step S9 in FIG. 7, so detailed description is omitted. Also, since the reference change rate over time in step S34 is obtained in the same manner as step S40 in FIG. 11, detailed description is omitted.

[0173] In step S31, the acquisition unit 41 acquires the pressure loss index value.

[0174] In step S32, the diagnostic unit 42 determines whether the pressure loss index value is equal to the clogging determination threshold Th.

[0175] If the pressure loss index value is equal to the clogging determination threshold Th (Yes in step S32), proceed to step S33. If the pressure loss index value is not equal to the clogging determination threshold Th (No in step S32), proceed to step S35.

[0176] In step S33, maintenance is performed on the filter 32. In modification 1D, the maintenance is performed by cleaning the filter 32.

[0177] In step S34, it is determined whether the difference between the reference maintenance interval a1 and the post-maintenance maintenance interval a2 is greater than a first determination value.

[0178] If the difference between the standard maintenance interval a1 and the post-maintenance maintenance interval a2 is greater than the first determination value (Yes in step S34), proceed to step S36. If the difference between the standard maintenance interval a1 and the post-maintenance maintenance interval a2 is equal to or less than the first determination value (No in step S34), proceed to step S37.

[0179] In step S35, it is determined whether the rate of change over time is greater than the reference rate of change over time b1. In modification 1D, the rate of change over time in step S35 is obtained at a time when the pressure loss index value (deceleration rate G) has not exceeded the clogging determination threshold value Th, which is different from the rate of change over time after maintenance in step S90 of FIG.

[0180] If the rate of change over time is greater than the reference rate of change over time b1 (Yes in step S35), proceed to step S36. If the rate of change over time is equal to or less than the reference rate of change over time b1 (No in step S35), return to step S31.

[0181] In step S36, the diagnosing unit 42 diagnoses that the bearing 30d of the fan motor 30 is abnormal.

[0182] In step S37, the diagnosing unit 42 diagnoses that the filter 32 is clogged.

[0183] In step S38, the output device 50 outputs the diagnosis result of the diagnosing unit 42. In modification 1D, the display unit 52 displays the diagnosis result (step S36) that the clogging state detected in step S7 is due to an abnormality in the bearing 30d of the fan motor 30.

[0184] The diagnostic system of the modified example 1D can quickly determine that the bearing 30d has a fault even if the maintenance threshold is not exceeded.

[0185] (5-5) Variation 1E In the present embodiment, the control device 40 acquires the deceleration rate G after the driving force of the rotating body is removed as information related to the motor load (pressure loss index value), but this is not limited to this. The control device 40 may acquire the information related to the load on the motor 30 from the load of the motor 30. The acquisition unit 41 acquires the load on the motor 30 from the current, voltage, power, or frequency of the motor 30. For example, the acquisition unit 41 may acquire the power value, the current value, or both the power value and the current value when the motor 30 is rotating at a predetermined rotation speed.

[0186] (5-6) Variation 1F The clogging determination threshold value Th may be a predetermined value or a value obtained from past measurements. This allows the accuracy of detecting clogging of the filter 32 or the condenser 24 to be changed. The predetermined value is, for example, the value at the time of product shipment. The value obtained from past measurements is, for example, a value obtained from measurements taken in an initial state where the filter 32 or the condenser 24 is unclogged, or a value obtained from measurements taken at one or more points in time from the initial state to the present.

[0187] To give a specific example, the clogging determination threshold Th is set in advance (e.g., at the time of product shipment) to a value that assumes a standard usage environment. When a product is brought into an environment where the relationship between the clogging determination threshold Th and pressure loss changes significantly (e.g., when the product is brought into an environment at high altitude (low air density)), environmental values ​​such as the density of the fluid supplied to the filter 32 or the condenser 24 are measured on-site in an initial, clog-free state. The clogging determination threshold Th is updated to a value determined according to the measured environmental values. This makes it possible to adjust the accuracy of clogging detection regardless of the usage environment conditions. Alternatively, by setting the clogging determination threshold Th according to the environmental values ​​measured in the initial state during product shipment inspection, it is possible to correct for individual product differences.

[0188] (5-7) Variation 1G The control device 40 may measure an increase in the deceleration rate G (pressure loss index value) by detecting a reduction in the time Td required for the speed of the fan 29 to decelerate from a first predetermined speed to a second predetermined speed. For example, the control device 40 measures the rotation speed Vr of the fan 29 based on sensor data output from a rotation sensor that detects the rotation of the motor 30. If the time Td required for the measured rotation speed Vr to decelerate from the first predetermined speed to the second predetermined speed is shorter than the reference time RT, the control device 40 determines that the measured deceleration rate G is greater than the clogging determination threshold Th.

[0189] (5-8) Variation 1H The control device 40 may measure the increase in the deceleration rate G by detecting a decrease in the number of rotations Nr of the fan 29 from when the driving force of the fan 29 is removed until the fan 29 stops. For example, the control device 40 measures the number of rotations Nr of the fan 29 based on sensor data output from a rotation sensor that detects the rotation of the motor 30. If the measured number of rotations Nr is less than the reference number of rotations RN, the control device 40 determines that the measured deceleration rate G is greater than the clogging determination threshold Th.

[0190] (5-9) Variation 1I The control device 40 may measure the increase in the deceleration rate G by detecting a decrease in the rotation speed rev after a predetermined time has elapsed since the speed of the fan 29 reached the first predetermined speed. For example, the control device 40 measures the rotation speed rev of the fan 29 based on sensor data output from a rotation sensor that detects the rotation of the motor 30. If the measured rotation speed rev is lower than the reference rotation speed Rrev, the control device 40 determines that the measured deceleration rate G is greater than the clogging determination threshold Th.

[0191] (5-10) Variation 1J The control device 40 may measure an increase in the deceleration rate G by detecting a reduction in the time Tv required for the peak value Vw of the back electromotive force of the motor 30 caused by the fan 29 to decrease from a first peak value to a second peak value. For example, the control device 40 measures the peak value Vw of the back electromotive force of the motor 30 caused by the fan 29 based on sensor data output from a voltage sensor that detects the voltage of the motor 30. If the time Tv required for the measured peak value Vw to decrease from the first peak value to the second peak value is shorter than the reference time RTv, the control device 40 determines that the measured deceleration rate G is greater than the reference value R.

[0192] (5-11) Variation 1K The control device 40 may measure the increase in the deceleration rate G by detecting a reduction in the time Tf required for the frequency f of the back electromotive force of the motor 30 caused by the fan 29 to decrease from a first frequency to a second frequency. For example, the control device 40 measures the frequency f of the back electromotive force of the motor 30 caused by the fan 29 based on sensor data output from a voltage sensor that detects the voltage of the motor 30. If the time Tf required for the measured frequency f to decrease from the first frequency to the second frequency is shorter than the reference time RTf, the control device 40 determines that the measured deceleration rate G is greater than the reference value R.

[0193] (5-12) Variation 1L The output device 50 may notify the user or an external device of the pressure drop increase information. The output device 50 may also notify the user or an external device of the diagnosis result. This allows the user or the external device to recognize whether the filter 32 or the condenser 24 is clogged, or whether there is an abnormality in the bearing 30d.

[0194] The pressure drop increase information output from the output device 50 may be information representing the clogging of the filter 32 or the condenser 24. This makes it possible to acquire information representing the clogging of the filter 32 or the condenser 24. The information representing the clogging of the filter 32 or the condenser 24 is, for example, the degree of clogging of the filter 32 or the condenser 24. By outputting the degree of clogging, the level of clogging of the filter 32 or the condenser 24 can be recognized.

[0195] (5-13) Variation 1M The control device 40 measures the degree of clogging, for example, by comparing a plurality of different clogging determination thresholds Th with the measured value of the deceleration G. The output device 50 changes the output format of the pressure loss increase information depending on the degree of clogging measured by the control device 40. This makes it possible to distinguish between different degrees of clogging by changing the output format. Examples of changes in the output format include changes in the intensity or pitch of sound, brightness or darkness of light, display content, and communication signals.

[0196] (5-14) Variation 1N The control device 40 may reverse the rotation of the fan 29 in response to an increase in the deceleration rate G, thereby causing the air A to flow backward. This makes it possible to clean and eliminate clogging in the filter 32 or the condenser 24. For example, when the deceleration rate G increases above the clogging determination threshold value Th, the control device 40 reverses the rotation of the fan 29 for a certain period of time.

[0197] (5-15) Variation 1O The clogging determination threshold Th may be changed according to the fluid density of the air A. This allows adjustment of the accuracy of detecting clogging of the filter 13 or the condenser 3. Even if the degree of clogging does not change, the deceleration G changes when the fluid density changes due to the temperature, humidity, pressure, type, etc. of the fluid. This is because the static pressure Ps and dynamic pressure Pv are correlated with the fluid density. The control device 50 can reduce clogging detection errors by correcting the clogging determination threshold Th according to the fluid density of the air A. The density of a fluid such as air A may be a constant determined according to the physical properties of the fluid, or may be actually measured by a sensor. Second Embodiment The fluid transport device may be applied to a liquid cooling device that cools a liquid other than oil. The liquid cooling device of the second embodiment may have the same configuration and effects as the oil cooling device 1 of the first embodiment. Explanation of the same configuration and effects as the oil cooling device 1 of the first embodiment will be omitted by citing the above explanation. The liquid cooling device of the second embodiment is, for example, a device that cools cutting fluid of a machine tool 90. Third Embodiment The fluid conveying device may be applied to a gas cooling device that cools gas. The gas cooling device of the third embodiment may have the same configuration and effects as the oil cooling device 1 of the first embodiment. Explanation of the same configuration and effects as the oil cooling device 1 of the first embodiment will be omitted by citing the above explanation. The gas cooling device of the third embodiment is, for example, an air conditioner that performs at least one of air conditioning operations, i.e., cooling and heating. In this case, the heat exchanger to which the fluid is supplied may be a heat exchanger that functions as a condenser or a heat exchanger that functions as an evaporator.

[0198] Although the embodiments have been described above, it will be understood that various changes in form and details are possible without departing from the spirit and scope of the claims. Various modifications and improvements, such as combinations with or substitutions for part or all of other embodiments, are possible.

[0199] For example, an "internal flow path" is not limited to a flow path inside a housing, as long as it is a flow path separated by a partition, but may also be a flow path inside a member other than the housing, such as a flow path (hollow portion) inside a pipe such as a duct.

[0200] The fluid transported along the internal flow path may be a gas other than air, or a liquid such as water, oil, etc. In other words, the fluid transport device may be a device that transports a gas other than air, or a device that transports a liquid such as water or oil, as long as it is a device that transports a fluid along the internal flow path by rotationally driving a rotor.

[0201] The rotating body that transports the fluid is not limited to a fan, but may be another rotating body, such as a rotating body in a pump. The pump may be, for example, a gear pump, a vane pump, etc. The motor that rotates the rotating body may be either an AC motor or a DC motor.

[0202] The structure provided in the flow path is not limited to the filter 32 or the condenser 24, but may be another structure such as the evaporator 25.

[0203] The maintenance of the structure is not limited to removing deposits by cleaning the filter 32. It may also be cleaning the condenser 24. It may also be cleaning both the filter 32 and the condenser 24. It may also be replacing either the filter 32 or the condenser 24, or replacing both the filter 32 and the condenser 24.

[0204] The fluid transport device 60 is not limited to a device provided in a cooling device that cools a fluid, but may be the cooling device itself. [Explanation of symbols]

[0205] 21...Compressor 22...Four-way switching valve 24...Condenser (first heat exchanger, structure) 25...Evaporator (second heat exchanger, structure) 23...Accumulator 29...Fan (rotating body) 30...Motor 30d...Bearing 1...Oil cooling device 3. Housing 31...Intake port 32...Filter (structure) 33…Air outlet 80...Bottom frame 81...Oil reservoir 40...Control device 41…Acquisition part 42...Diagnostics Department 43...Control unit 45...Drive circuit 46...heat sink 50...Output device 51...Information Department 52...Display section 60...Fluid transport device 61...Flow path 62…Inner wall 90…Machine tools 100...Diagnostic System EV: Electronic expansion valve HGB...Hot gas bypass valve L1, L2, L3, L4...piping L10...Hot gas bypass piping P...Circulation pump RC…Refrigerant circuit T...Oil tank V1, V2...Shut-off valves [Prior art documents] [Patent documents]

[0206] [Patent Document 1] Japanese Patent Publication No. 2022-155832

Claims

1. A diagnostic system for diagnosing a fluid transport device (60) having a rotating device including a rotating body (29) that transports a fluid by rotating, a motor (30) that drives the rotating body (29), and a bearing (30d) of the motor, and a structure (24, 25, 32) that is provided in a flow path (61) of the fluid and forms a path through which the fluid passes, The rotating body (29) has a characteristic that a load torque increases as a pressure loss in the fluid flow path (61) increases, The diagnostic system comprises: an acquisition unit (41) that acquires information about the load of the motor; A diagnostic unit (42); a notification unit that issues a notification prompting maintenance when the diagnosis unit performs a diagnosis prompting maintenance of the structure; Equipped with The diagnostic unit performing a diagnosis to prompt maintenance of the structure by making a first determination regarding maintenance of the structure based on information about the load of the motor; and when the interval between notifications by the notification unit is shortened to a predetermined level after the maintenance of the structure, a second determination is made regarding an abnormality in a bearing of the motor of the rotating device, thereby performing a diagnosis to determine a failure. A diagnostic system (100).

2. The diagnostic unit performs the second judgment based on time-series information regarding the timing to prompt the maintenance, thereby making a diagnosis to determine a fault. The diagnostic system of claim 1 .

3. The time-series information regarding the timing of the maintenance prompt includes information regarding the interval at which the maintenance prompt is to be prompted. The diagnostic system of claim 2 .

4. the information about the load of the motor includes a deceleration rate after the driving force of the rotating body is removed or a load of the motor; The acquisition unit The degree of deceleration is obtained as a deceleration time or a deceleration rate of the rotating body, and the load of the motor is obtained from a current, a voltage, a power, or a frequency of the motor. The diagnostic system according to claim 1 or 2.

5. the structure is a filter or a heat exchanger; The maintenance is replacement of the structure or removal of deposits. The diagnostic system according to claim 1 or 2.

6. The first determination includes a determination regarding clogging of the structure. The diagnostic system according to claim 1 or 2.

7. The diagnostic unit When the information regarding the load of the motor exceeds a predetermined maintenance threshold (Th), a diagnosis is performed to prompt the maintenance. The diagnostic system according to claim 1 or 2.

8. the diagnosing unit performs the second determination to make a diagnosis of a fault when the information regarding the load on the motor does not return to a predetermined value after the maintenance is completed. The diagnostic system of claim 1 .

9. the diagnosing unit performs the second determination when a change amount of information relating to the load of the motor before and after the maintenance becomes smaller than a predetermined amount, thereby performing a diagnosis to determine a fault. The diagnostic system of claim 8.

10. the diagnosing unit performs the second determination when a rate of change over time of the information relating to the load of the motor becomes greater than a predetermined value immediately after the maintenance, thereby performing a diagnosis to determine a failure. The diagnostic system of claim 1 .

11. The diagnostic unit When a rate of change over time of the information on the load of the motor becomes larger than a predetermined value at a time point when the information on the load of the motor does not exceed a maintenance threshold, the second determination is made to perform a diagnosis for determining a fault. The diagnostic system of claim 1 .

12. A diagnostic method for diagnosing a fluid transport device (60) having a rotating device including a rotating body (29) that transports a fluid by rotating, a motor (30) that drives the rotating body (29), and a bearing (30d) of the motor, and a structure (24, 25, 32) that is provided in a flow path (61) of the fluid and forms a path through which the fluid passes, comprising: The rotating body (29) has a characteristic that a load torque increases as a pressure loss in the fluid flow path (61) increases, The diagnostic method comprises: an acquisition step of acquiring information about a load of the motor; A diagnostic step; a notification step of issuing a notification prompting maintenance when a diagnosis prompting maintenance of the structure is performed by the diagnosis step; Equipped with The diagnostic step includes: performing a diagnosis to prompt maintenance of the structure by making a first determination regarding maintenance of the structure based on information about the load of the motor; and when the interval between the notifications made by the notification step is shortened to a predetermined level after the maintenance of the structure, a second determination is made regarding an abnormality in a bearing of the motor of the rotating device, thereby performing a diagnosis to determine a failure. Diagnostic methods.

13. A diagnostic program for realizing, by a computer, a diagnostic system for diagnosing a fluid transport device (60) having a rotating device including a rotating body (29) that transports a fluid by rotating, a motor (30) that drives the rotating body (29), and a bearing (30d) of the motor, and a structure (24, 25, 32) that is provided in a flow path (61) of the fluid and forms a path through which the fluid passes, The rotating body (29) has a characteristic that a load torque increases as a pressure loss in the fluid flow path (61) increases, Computer, an acquisition means for acquiring information about a load of the motor; diagnostic means; When the diagnosis means performs a diagnosis to prompt maintenance of the structure, the notification means functions as a notification means to issue a notification to prompt the maintenance, The diagnostic means comprises: performing a diagnosis to prompt maintenance of the structure by making a first determination regarding maintenance of the structure based on information about the load of the motor; and when the interval between notifications by the notification means becomes shorter to a predetermined level after maintenance of the structure, a second determination is made regarding an abnormality in a bearing of the motor of the rotating device, thereby performing a diagnosis to determine a failure. Diagnostic program.

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