Device-state diagnosis device and device-state diagnosis method

Abstract

This device-state diagnosis device (13) is characterized by comprising: a sensor (23) for measuring the state of a device to be diagnosed; a state diagnosis unit (16) for diagnosing the state of a component constituting the device to be diagnosed on the basis of a measurement value of the sensor; an information processing unit (20) for outputting, to the state diagnosis unit, performance data of a replacement component which, among components, is a component to be replaced; and an output control unit (17) for displaying the state of the component. The device-state diagnosis device is also characterized in that: when the device to be diagnosed is operated after the replacement of the replacement component, the state diagnosis unit uses the performance data and the measurement value of the sensor to diagnose the performance of a diagnosis component, which, among the components is not a component to be replaced; and the output control unit displays the diagnosis result of the diagnosis component.

Description

Equipment status diagnosis device and equipment status diagnosis method

[0001] The present invention relates to an apparatus and method for diagnosing a device that is made up of a plurality of parts and for which parts are replaced as part of maintenance.

[0002] Recently, in order to conserve resources, it has become important to support a circular economy that recycles resources. Therefore, there is a need to partially replace components of equipment that have deteriorated over time due to long-term use, and continue using the equipment. To replace components at the appropriate time, it is necessary to estimate their deterioration state. One possible method is to obtain the operating status of components from sensors built into the equipment.

[0003] As a technology for determining whether or not there is an abnormality from sensor information, for example, Patent Document 1 discloses a shutoff valve control system including a shutoff valve, an air cylinder that controls the rotation of the valve stem of the shutoff valve, and a solenoid valve that supplies air from an air supply source to and exhausts air from the cylinder of the air cylinder, and control means for controlling the opening of the shutoff valve, the shutoff valve control system including: a pressure sensor that detects the internal pressure of the cylinder; determination means that determines whether the system is normal or abnormal based on the pressure characteristics of the internal cylinder pressure actually measured by the pressure sensor when air is supplied from the air supply source to the cylinder of the air cylinder under the control of the control means; and storage means that pre-stores the pressure characteristics of the internal cylinder pressure during initial normal operation of the system and the pressure characteristics of a failure prediction boundary, the determination means determining that the system is normal if the actually measured pressure characteristics are within a range between the pressure characteristics during normal operation and the pressure characteristics of the failure prediction boundary, and determining that there is an abnormality if the actually measured pressure characteristics are outside the range between the pressure characteristics during normal operation and the pressure characteristics of the failure prediction boundary.

[0004] The shutoff valve control system detects the internal pressure of the air cylinder in three periods: "up to the start of air cylinder operation," "from the start of air cylinder operation to the start of shutoff valve operation," and "after the start of shutoff valve operation."The shutoff valve control system then detects abnormalities in the solenoid valve, air cylinder, and shutoff valve based on the internal pressure values ​​for each period.

[0005] JP 2012-52652 A

[0006] The shutoff valve control system in Patent Document 1 is composed of many components, such as a shutoff valve, solenoid valve, and air cylinder, but only has one sensor: a pressure sensor that detects the internal pressure of the air cylinder. This shutoff valve control system is based on the premise that force is transmitted unidirectionally over time (in stages), from solenoid valve to air cylinder to shutoff valve. Furthermore, Patent Document 1 does not distinguish between the solenoid valve, air cylinder, and shutoff valve as components that require frequent replacement and those that do not, and does not mention using the timing of replacing one component to diagnose the deterioration of other components.

[0007] However, if any of multiple components connected to each other in a circular and simultaneous manner, such as by a flow path, deteriorates, the sensor output may fluctuate simultaneously and with the same trend. In such cases, it becomes difficult to determine the degree of deterioration of each component from sensor information alone. As a result, the accuracy of state estimation decreases significantly. Adding sensors would make this determination possible, but would require additional costs. Therefore, the present invention aims to take advantage of the opportunity to replace a component that constitutes the equipment and appropriately measure the performance of each component that constitutes the equipment using information from the same type of sensor.

[0008] The equipment status diagnosis device of the present invention comprises a sensor that measures the status of a diagnosis target device, a status diagnosis unit that diagnoses the status of components constituting the diagnosis target device based on measurements taken by the sensor, an information processing unit that outputs performance data of replacement components that are to be replaced to the status diagnosis unit, and an output control unit that displays the status of the components, wherein, after the replacement components are replaced, when the diagnosis target device is operated, the status diagnosis unit diagnoses the performance of the diagnosis components that are not to be replaced using the performance data and measurements taken by the sensor, and the output control unit displays the diagnosis results of the diagnosis components. Other means will be described in the description of the preferred embodiment of the invention.

[0009] According to the present invention, when a component constituting a device is replaced, the performance of each component constituting the device can be appropriately measured using information from the same type of sensor.

[0010] FIG. 1 is a diagram explaining a basic concept common to Examples 1 to 3. FIG. 2 is a diagram showing the overall configuration of an equipment status diagnosis device in Example 1. FIG. 3 is a diagram showing a detailed structure of a diagnosis target device. FIG. 4 is a diagram showing an operation flow in Example 1. FIG. 5 is a display example of a user interface. FIG. 6 is a diagram showing another overall configuration of an equipment status diagnosis device in Example 1. FIG. 7 is a diagram showing an operation flow in Example 2. FIG. 8 is a diagram explaining the performance of a replaceable part, a replacement part, and a diagnosis part. FIG. 9 is a display example of a user interface. FIG. 10 is a diagram showing the operation flow in Example 3. FIG. 11 is a diagram explaining the performance of a replaceable part, a replacement part, and a diagnosis part. FIG. 12 is a block diagram of a computer.

[0011] (Basic Concept) Below, Examples 1 to 3 of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram illustrating the basic concept common to Examples 1 to 3. First, attention is drawn to the upper diagram of FIG. 1. The upper diagram of FIG. 1 shows a circulation system including a replacement part 9, a diagnostic part 7, and a sensor 23. These are connected by piping through which a circulating agent circulates. The arrows indicate the flow direction of the circulating agent. This direction may also be reversed. The circulating agent may be in a gas phase, a liquid phase, or a mixture thereof. In general, the replacement part 9 and the diagnostic part 7 may be connected in terms of the flow of fluid, electricity, or heat. The physical quantity measured by the sensor 23 is not particularly limited as long as it is the same type of physical quantity, and may be temperature, flow rate, flow velocity, etc. However, for simplicity, the following describes an example in which the sensor 23 measures temperature.

[0012] Among the components constituting the device to be diagnosed, those that are subject to replacement are called replacement components 9. Furthermore, among the components constituting the device to be diagnosed, those that are not replacement components are called diagnosis components 7. In this embodiment, the performance of the diagnosis components 7 that are not subject to replacement is diagnosed using performance data and the measurement values ​​of the sensor 23. More specifically, in this embodiment, the part that is not subject to replacement is set as the diagnosis component 7, and the performance of the diagnosis component 7 is diagnosed using "performance data of the replacement component 9" and "the state of the device to be diagnosed measured by the sensor 23 (measurement values ​​of the sensor 23)."

[0013] The replacement part 9 is a part that is replaced with a new one at a relatively short interval. The diagnostic part 7 is a part that is replaced at a sufficiently long interval compared to the replacement part 9. The sensor 23 measures the temperature of the circulating agent over time. Performance is defined for each of the replacement part 9 and the diagnostic part 7. The performance is a value between 0% and 100%. When a part is new, the performance is "100%". When a part is completely worn out and can no longer perform its function, the performance is "0%".

[0014] Now, let's assume that the circulating agent is oil, the replacement part 9 is an oil filter, and the diagnostic part 7 is an oil cooler. When the replacement part 9 deteriorates and its performance declines, the temperature of the circulating agent rises, and the measurement value of the temperature sensor 23 also rises. When the diagnostic part 7 deteriorates and its performance declines, the temperature of the circulating agent rises, and the sensor measurement also rises. In this way, the deterioration of both the replacement part 9 and the diagnostic part 7 appears as a rise in the temperature of the circulating agent.

[0015] The performance of each of the replacement part 9 and the diagnostic part 7 can be analyzed by dividing it into two values: a "true value" and an "estimated value." Of these, the "true value" is a value that can only be determined after a rigorous analysis is performed by the manufacturer, designer, etc. of the part. The manufacturer, etc. often takes the part back to a factory, etc., and measures the true value using special analytical equipment. Conversely, the user of the device that includes the part cannot know the "true value" on-site. On the other hand, the "estimated value" is a value that the user simply estimates the performance on-site based on sensor measurements.

[0016] Next, let's look at the central diagram in Figure 1. Multiple ●31 are drawn in a three-dimensional space with the performance (%) of the replacement part, the performance (%) of the diagnosed part, and the sensor measurement value (°C) as axes. These multiple ●31 are the results drawn by manufacturers and others after conducting experiments in their own factories. In other words, the performance of the diagnosed part is the true value Ar, and the performance of the replacement part is also the true value Br. The manufacturers and others analyze the relationship between these.

[0017] Furthermore, let's look at the bottom diagram of Figure 1. The condition diagnosis unit of the equipment condition diagnosis device creates a regression surface 32 that minimizes the sum of squares of the distances to each ● 31 in the center diagram of Figure 1. The bottom diagram of Figure 1 shows the result. For simplicity, in the bottom diagram of Figure 1, the regression surface 32 is shown as a plane. The closer the regression surface 32 is to the origin, the higher it is located. In other words, if the performance of the replacement part deteriorates, the sensor measurement value will increase, and if the performance of the diagnosed part deteriorates, the sensor measurement value will also increase.

[0018] When such a regression surface 32 is prepared, the condition diagnosis unit can calculate an estimate of the performance of the diagnostic part as an unknown value based on the sensor measurement values ​​and the performance of the diagnostic part as known values. Similarly, the condition diagnosis unit can calculate an estimate of the performance of the diagnostic part as an unknown value based on the sensor measurement values ​​and the performance of the diagnostic part as known values.

[0019] Now, consider the following function F: T = F(As, Bs)

[0020] As is an estimated value of the performance of the replacement part. Bs is an estimated value of the performance of the diagnosed part. T is the sensor measurement value. The regression surface 32 is the function F itself, and "δT / δAs<0" and "δT / δBs<0" hold. Let Tp be the sensor measurement value at time p just before the replacement part 9 is replaced with a new part, and let Tq be the sensor measurement value at time q when the operation of the device including the part is resumed after the replacement part 9 has been replaced with a new part and the sensor measurement value has stabilized. In many cases, "Tp>Tq" holds.

[0021] The condition diagnosis unit solves the equation "Tq = F(Ans, Bs)". Bs is an estimated value of the performance of the diagnosed part. Ans is an estimated value of the performance of a new replacement part. The condition diagnosis unit assumes that Ans = 100% holds. Therefore, of the variables in the equation, Tq and Ans are known, and Bs is unknown. In this way, the condition diagnosis unit calculates the specific value of Bs. Then, Bs becomes known.

[0022] The condition diagnosis unit solves the equation "Tp = F(Aus, Bs)", where Aus is an estimated value of the performance of the removed replacement part. Of the variables in the equation, Tp and Bs are known, and Aus is unknown. In this way, the condition diagnosis unit calculates a specific value for Aus.

[0023] The condition diagnosis unit uses the function F in this way to estimate the performance of either the replacement part or the diagnosed part. However, when a value higher (lower) than the true value is input as the known performance of one part, the condition diagnosis unit outputs a value lower (higher) than the true value as the unknown performance of the other part. When the regression surface 32 in the lower diagram of FIG. 1 is cut horizontally through the sensor measurement value Tp, a curve appears on the horizontal cross section. This curve indicates the combination of Aus and Bs that results in the sensor measurement value Tp. The larger Aus, the smaller Bs. Furthermore, if Aus is larger (smaller) than the true value of the performance of the removed replacement part, Bs will be smaller (larger) than the true value of the performance of the diagnosed part (as described below in Example 3).

[0024] Although Examples 1 to 3 are examples in which the equipment condition diagnosis device diagnoses the deterioration of a diagnosis target device, which is an oil-lubricated air screw compressor, the present invention is widely applicable to examples in which the same type of sensor is used to diagnose the condition of a diagnosis target device that has both a replacement part 9 that is replaced at relatively short intervals and a diagnosis part 7 that is used for a longer period without being replaced.

[0025] Example 1 Example 1 of the present invention will be described with reference to Figures 2 to 6. Figure 2 is a diagram showing the overall configuration of an equipment status diagnosis device in Example 1. An equipment status diagnosis device 13 includes a sensor 23, a status diagnosis unit 16, an output control unit 17, a user interface (UI) 18, an information processing unit 20, and a characteristic database (DB) 21. A diagnosis target device 14 exists separately from the equipment status diagnosis device 13.

[0026] The equipment status diagnosis device 13 diagnoses a diagnosis target device 14. The sensor 23 generally measures the state of the diagnosis target device 14, but in Example 1, it measures the temperature inside the diagnosis target device 14. The diagnosis target device 14 includes a replacement part 9 and a diagnosis part 7. The diagnosis part 7 is physically connected to the replacement part 9 by, for example, a flow path or the like. When the replacement part 9 deteriorates, the measurement value (°C) of the sensor 23 increases. When the diagnosis part 7 deteriorates, the measurement value of the sensor 23 also increases.

[0027] The replacement part 9 in Fig. 2 corresponds to the oil filter 9 in Fig. 3. The diagnosis part 7 in Fig. 2 corresponds to the oil cooler 7 in Fig. 3. The scope of application of the present invention is not limited to the case where there is only one sensor 23. The condition diagnosis unit 16 uses the measurement value of the sensor 23 to diagnose the deterioration state of the components of the diagnosis target device 14 and outputs the result to the output control unit 17. The user interface 18 is a component that exchanges information with the user, and, for example, inputs information from the user and outputs information to the user on a screen.

[0028] The information processing unit 20 outputs the part replacement information received from the user interface 18 to the condition diagnosis unit 16. The information processing unit 20 also reads replacement part performance data from a characteristic database (DB) 21 and outputs the data to the condition diagnosis unit 16. The condition diagnosis unit 16 performs a deterioration diagnosis of the component parts using the replacement part performance data and outputs the results to the output control unit 17. The output control unit 17 outputs the results of the diagnosis by the condition diagnosis unit 16 to the user interface 18.

[0029] (Configuration as a microcomputer) The equipment status diagnosis device 13 includes a microcomputer (not shown) therein. This microcomputer includes a central control unit, a main memory, and an auxiliary memory. The auxiliary memory stores a characteristic database 21. The status diagnosis unit 16, output control unit 17, and information processing unit 20 are programs. The central control unit reads these programs from the auxiliary memory to the main memory, thereby realizing the functions (information processing) previously described in each program.

[0030] Figure 3 is a diagram showing the detailed structure of the diagnosis target device 14. The power supply 1, inverter 2, and motor 3 are electrically connected. The compression mechanism 4 includes a male rotor, a female rotor, a casing, and a shaft 19. The motor 3 and the male shaft 19 are mechanically coupled, and the rotational torque of the motor 3 is transmitted to the shaft 19 and the male rotor. As the male rotor and the meshing female rotor rotate, the volume of the compression chamber changes, compressing the air in the compression mechanism 4. In other words, the diagnosis target device 14 in Figure 3 (excluding the sensor 23) is a gas compressor (oil-lubricated air screw compressor).

[0031] A sensor 23 is provided downstream of the compression mechanism 4. The sensor 23 measures the mixed temperature of air and lubricating oil (corresponding to the circulating agent in FIG. 1 ). A separator tank 5 is provided further downstream of the sensor 23. The downstream side of the separator tank 5 branches into two paths: an air path and a lubricating oil path. The air path is connected to an aftercooler 12, which is a heat exchanger that cools the compressed air. Further downstream of the aftercooler 12, an air tank and pneumatic equipment (not shown) are provided outside the device 14 to be diagnosed.

[0032] Meanwhile, an oil cooler 7 (corresponding to the diagnostic part 7 in FIG. 1 ), which is a heat exchanger that cools the lubricating oil, is provided downstream of the separator tank 5 in the lubricating oil flow path. The downstream side of the oil cooler 7 is connected to an oil filter 9 (corresponding to the replacement part 9 in FIG. 1 ). The downstream side of the oil filter 9 is again connected to the compression mechanism 4. The oil cooler 7 is provided in the same space as the aftercooler 12 so as to be adjacent thereto, and a cooler fan 8 is provided in the flow path that connects to that space.

[0033] The intake filter 10 is disposed between a pipe (not shown) connected to the outside air and the compression mechanism 4, and removes foreign matter such as dust from the intake air. The intake throttle valve 11 is disposed downstream of the intake filter 10, and adjusts the amount of intake air by controlling its own opening. The downstream side of the intake throttle valve 11 is connected to the compression chamber in the compression mechanism 4.

[0034] The flow of compressed air in the normal compression operation mode in the above configuration will be described. Based on the power supplied from the power source 1, the inverter 2 controls the voltage waveform and the rotation speed of the motor 3. The rotation torque of the motor 3 is transmitted to the male and female rotors in the compression mechanism 4 via the shaft 19. The male and female rotors change the volume of the compression chambers formed between them to suck, compress, and discharge air.

[0035] During the compression stroke, lubricating oil, which is at a lower temperature than the compressed air, is supplied to cool the hot air and seal gaps between rotors and other parts to prevent leakage. The high-temperature, high-pressure compressed air and lubricating oil are then discharged into the separator tank 5 located downstream. The compressed air and lubricating oil that flow into the separator tank 5 in a mixed state are directed to form a swirling flow, and are separated into compressed air and lubricating oil by centrifugal force. The compressed air flows into the aftercooler 12, where it is sufficiently cooled, before being discharged into an air tank or the like.

[0036] Meanwhile, the lubricating oil is separated from the compressed air in the separator tank 5 and stored below. The oil cooler 7, located downstream on a separate path from the air, then cools the lubricating oil to a low temperature. After cooling, the lubricating oil passes through an oil filter 9, which removes solid impurities from the fluid, and is then supplied again to the compression chambers in the compression mechanism 4. At this time, the pressure in the compression chambers to which oil is being supplied is lower than the discharge pressure (≈ the internal pressure of the separator tank 5), so oil is supplied due to the pressure difference.

[0037] At this time, there is a possibility that minute amounts of moisture and dirt from the air may be mixed into the lubricating oil, which causes dirt to gradually adhere to the wall surfaces of the lubricating oil passages in the oil cooler 7. As a result, the thermal resistance gradually increases over long-term use, and the cooling performance of the heat exchanger deteriorates.

[0038] Next, cooling in the aftercooler 12 and the oil cooler 7 will be described. Both of these heat exchangers are air-cooled. Cooling air generated by the cooler fan 8 passes between the cooling fins on the surfaces of these heat exchangers, thereby cooling the compressed air and lubricating oil flowing inside the heat exchangers. In the first embodiment, one cooler fan 8 is provided downstream of the aftercooler 12 and the oil cooler 7 with respect to the flow direction of the cooling air.

[0039] The cooling air passing through the aftercooler 12 and the oil cooler 7 is supplied by drawing air around the diagnosis target device 14 into the housing of the diagnosis target device 14. At this time, if dust is present in the air around the diagnosis target device 14, the dust will collide with the surfaces of the cooling fins of the aftercooler 12 and the oil cooler 7 along with the cooling air from the cooler fan 8 and gradually adhere to them. When dust adheres to the surfaces of the cooling fins, thermal resistance increases and the cooling performance of the heat exchanger decreases.

[0040] As described above, the cooling performance of the diagnostic target device 14 gradually declines over a long period of use, resulting in so-called aging degradation. The aftercooler 12 and the oil cooler 7 are not parts that are typically replaced during regular maintenance. However, from the perspective of a circular economy that reduces resources through the continued use of equipment, these parts must be replaced if they have deteriorated significantly.

[0041] However, because the degree of deterioration varies greatly depending on the usage environment, it is important to estimate the degree of deterioration for each piece of equipment and replace it at the appropriate time. In particular, if it were possible to estimate the condition of parts from sensor information, etc., without shutting down the equipment in operation during deterioration diagnosis, it would be possible to avoid the loss of economic efficiency for users due to the stoppage of production activities that accompanies shutting down the equipment for diagnosis.

[0042] As described above, when the cooling performance of the oil cooler 7 deteriorates, it becomes unable to sufficiently cool the lubricating oil that has become hot after cooling the air in the compression mechanism 4, and the outlet temperature of the oil cooler 7 rises. The lubricating oil with the increased temperature is fed back to the compression mechanism 4, so the temperatures of the air and lubricating oil discharged from the compression mechanism 4 rise, and are measured by the sensor 23.

[0043] As a result, if the temperature measured by the sensor 23 is high even under the same operating conditions, it can be assumed that deterioration has occurred in the oil cooler 7. For example, a heat transfer analysis model of this device can be separately constructed and the thermal resistance of the oil cooler 7 at that temperature can be estimated to quantitatively estimate the degree of deterioration of the oil cooler 7. Alternatively, the quantitative degree of deterioration of the oil cooler 7 can also be estimated by previously obtaining the relationship between the temperature rise of the sensor 23 and the deterioration state (thermal resistance) of the oil cooler 7 through an experiment or the like.

[0044] On the other hand, if the oil filter 9 installed in the lubricating oil circulation path traps dirt particles and the like, and as a result the flow resistance of the oil filter 9 increases, the amount of oil supplied to the compression mechanism 4 decreases due to the pressure difference. If the amount of oil supplied decreases, the compression mechanism 4 will not be able to sufficiently cool the air that has been heated by compression. As a result, the temperature at the outlet of the compression mechanism 4 measured by the sensor 23 will rise.

[0045] Therefore, if the thermal resistance of the oil cooler 7 increases and if the flow resistance of the oil filter 9 increases, the temperature measured by the sensor 23 will rise. It is difficult to determine the extent to which the oil cooler 7 or the oil filter 9 has deteriorated based on this sensor information. In particular, the cost of replacing the oil cooler 7 is higher than the cost of replacing the oil filter 9, so replacement of the oil cooler 7 (and the integrated aftercooler 12) must be planned more carefully. Despite this, the low accuracy of predictions for planning this replacement has been an obstacle to realizing a circular economy.

[0046] Therefore, in the first embodiment, attention is paid to the fact that the oil filter 9 is replaced with a new one during periodic maintenance, and an appropriate and highly accurate state estimation of the oil cooler 7 is performed.

[0047] 4 is a diagram showing the flow of operations in Example 1. In step S101, the diagnosis target device 14 performs normal operation. In step S102, the condition diagnosis unit 16 acquires sensor measurement values ​​from the sensor 23 during normal operation of the diagnosis target device 14 and stores them in the auxiliary storage device as sensor history data. The sensor value here is the mixed temperature of air and lubricating oil.

[0048] In step S103, the condition diagnosis unit 16 determines whether a predetermined part replacement time has elapsed. Specifically, if the predetermined part replacement time has elapsed (step S103 "Yes"), the condition diagnosis unit 16 proceeds to step S104, and otherwise (step S103 "No"), the condition diagnosis unit 16 returns to step S101.

[0049] In step S104, the diagnosis target device 14 stops operation. In step S105, the condition diagnosis unit 16 instructs the user via the user interface 18 to replace a predetermined replacement part 9 as maintenance for the diagnosis target device 14. The user then replaces the predetermined replacement part 9. The predetermined replacement part 9 is, for example, an oil filter 9 with a short replacement cycle.

[0050] As the first process of step S106, the information processing unit 20 receives input via the user interface 18 indicating that the part has been replaced, and further receives input of the performance of the new replacement part as "replacement part performance data." The user has previously obtained the performance of the new oil filter 9 through experiments or the like.

[0051] As the second process of step S106, the information processing unit 20 receives, via the user interface 18, a user's input indicating that a diagnostic operation will be performed to diagnose the diagnostic component 7 (oil cooler 7) of the diagnosis target device 14. The information processing unit 20 then reads the replacement part performance data from the characteristic database 21 and outputs it to the condition diagnosis unit 16. The condition diagnosis unit 16 then determines that the performance of the oil filter 9 after maintenance has recovered to the performance (100%) indicated by the replacement part performance data. At this time, the condition diagnosis unit 16 may obtain an identifier that uniquely identifies the replaced part and the performance of the part from a tag or the like attached to the replaced part, without waiting for a user operation.

[0052] Thereafter, when the diagnosis target device 14 starts up and the measurement value of the sensor 23 stabilizes, the condition diagnosis unit 16 performs a condition diagnosis of the diagnosis component 7 using the sensor history data (measurement value of the sensor 23) and the replacement component performance data (performance of the new oil filter 9). More specifically, the condition diagnosis unit 16 solves the equation "Tq = F(Ans, Bs)" to calculate the unknown Bs. At this time, the performance Ans of the oil filter 9 is determined, so the condition diagnosis unit 16 can also accurately estimate the performance of the oil cooler 7 (diagnosis component 7 in FIG. 1 ) from the measurement value of the sensor 23.

[0053] In step S107, the state diagnosis unit 16 outputs Bs as the state estimation result of the oil cooler 7 to the output control unit 17. Then, the output control unit 17 displays Bs via the user interface 18 (display, etc.).

[0054] 5 is a display example of the user interface 18. The user interface 18 indicates that the oil filter 9 immediately after replacement is in a new condition, and outputs the state estimation result for the oil cooler 7 that has not been replaced.

[0055] 5 , the output control unit 17 may display the performance of the oil cooler 7 in specific numerical values ​​(such as the ratio Bs of performance to that of a new product), or may display the replacement time that can be estimated from the rate of deterioration. Furthermore, the output control unit 17 may display the cost required for replacement, the economic effect of replacement (the increase in efficiency due to the prevention of deterioration converted into a monetary value), or the environmental load reduction effect associated with the replacement, such as the effect of reducing greenhouse gas emissions. Furthermore, the output control unit 17 is not limited to outputting to a display, but may also output as an electronic file or on paper.

[0056] According to the first embodiment, when a deterioration state that is difficult to determine from sensor information occurs in both the oil cooler 7, which is not usually replaced frequently, and the oil filter 9, which is replaced periodically, it is possible to determine and accurately estimate the deterioration state. Furthermore, according to the first embodiment, it is possible to create an appropriate replacement plan for parts with high replacement costs, such as the oil cooler 7, thereby improving economic and environmental value for the user.

[0057] 6 is a diagram showing another overall configuration of the equipment status diagnosis device in Example 1. As shown in FIG. 6, some of the elements constituting the equipment status diagnosis device 13 may be installed separately in a location remote from the diagnosis target device 14. In this case, the diagnosis target device 14 side is called an edge unit 13a, and the part located in a remote location from the edge unit 13a via a communication network 22 is called a server unit 13b. The edge unit 13a and the server unit 13b can send and receive data via the communication network 22, and can perform the functions described in Example 1 in substantially the same way as if all the elements were located in the same place as shown in FIG. 2.

[0058] Furthermore, by consolidating the condition diagnosis unit 16, which has a large computational load, into the server unit 13b and increasing the information processing capacity of the server unit 13b, it becomes possible to perform condition estimation at high speed while reducing the cost of the edge unit 13a, which includes the diagnosis target device 14.

[0059] <Embodiment 2> Embodiment 2 of the present invention will be described with reference to Figures 7 to 9. Below, a description of the same configuration and operation as in embodiment 1 will be omitted, and differences from embodiment 1 will be described. Figure 7 is a diagram showing the flow of operation in embodiment 2. A feature of embodiment 2 that differs from embodiment 1 is the addition of the processes of steps S108 and S109 in Figure 7.

[0060] In step S108, the information processing unit 20 accepts, via the user interface 18, a user's input indicating that a diagnostic operation will be performed to diagnose the part to be replaced (the oil filter 9 before replacement) of the diagnosis target device 14. Thereafter, the condition diagnosis unit 16 performs a condition diagnosis of the part to be replaced using the sensor history data (measurements of the sensor 23). More specifically, the condition diagnosis unit 16 solves the equation "Tp=F(Aus, Bs)" to calculate the unknown quantity Aus.

[0061] In step S109, the condition diagnosis unit 16 calculates the performance improvement effect resulting from replacing the replacement part 9 and outputs the result to the output control unit 17. The output control unit 17 then displays the performance improvement effect via the user interface 18. Thus, the second embodiment is characterized in that it estimates the performance of the part to be replaced, i.e., the oil filter 9 removed during replacement work during regular maintenance.

[0062] FIG. 8 is a diagram illustrating the performance of the replaced part (oil filter 9 before replacement), the replaced part (oil filter 9 after replacement), and the diagnosed part (oil cooler 7). The vertical axis in FIG. 7 represents the performance of the replaced part, the replaced part, and the diagnosed part. Specifically, the performance refers to the cooling performance of the oil cooler 7 (diagnosed part), the flow rate relative to the pressure difference of the oil filter 9 (replaced part or replaced part), etc. The standard "100%" represents the performance of each part in a brand new state with no deterioration.

[0063] A pair of bar graphs showing "performance (true value)" and "performance (estimated value)" are provided for the diagnosed part and the replaced part before part replacement, and for the diagnosed part and the replaced part after part replacement. The user cannot know the true value on-site. The estimated value is performance estimated by the condition diagnosis unit 16 using the function F.

[0064] As described in the first embodiment, immediately after replacing a replacement part, the condition diagnosis unit 16 assumes that the performance of the replacement part is the same as the previously acquired performance data of the replacement part when it was new. At this time, the performance of the replacement part is estimated to have recovered to 100% (<1>). Once the condition of the replacement part is determined, the condition diagnosis unit 16 can accurately estimate the performance of the part being diagnosed (oil cooler 7) based on the value of the sensor 23, as shown in <2>.

[0065] Next, the condition diagnosis unit 16 estimates the condition before the part replacement. The condition diagnosis unit 16 first assumes that the performance of the diagnostic part (oil cooler 7) that has not been replaced will not change before and after the part replacement, and determines an estimated value for the performance of the diagnostic part (<3>). The condition diagnosis unit 16 can accurately estimate the performance of the part to be replaced (oil filter 9 that was used before replacement) by using the value of <3> and the measurement value of the sensor 23 obtained before the part replacement (<4>).

[0066] As described above, the condition diagnosis unit 16 can accurately estimate the performance (degree of deterioration) of both the replaced part before the part replacement and the replacement part after the part replacement. Therefore, by comparing these, the condition diagnosis unit 16 can quantitatively indicate the degree of change (effect) obtained by the part replacement.

[0067] 9 shows an example of the display of the user interface 18 (18a, 18b). In addition to the performance estimation result of the oil cooler 7 described in the first embodiment, the user interface 18 displays, as numerical values, the performance improvement result of the oil filter 9 as a result of replacing the oil filter 9. As in the first embodiment, the output format may be electronic data or paper output. Furthermore, because the rate of deterioration can be estimated from the degree and duration of performance degradation, the user interface 18 may also display an indication of when the next replacement will occur.

[0068] In this way, it is possible to accurately estimate not only the performance after part replacement but also the performance before the part replacement by retroactively estimating the performance. In addition to the effects shown in the first embodiment, by presenting the effect of the part replacement itself and the next replacement time of the replacement part to the user, it is possible to obtain an effect on the replacement cost. This promotes part replacement at the appropriate time and maintains the performance of the equipment, thereby improving the economic and environmental value for the user.

[0069] Third Embodiment A third embodiment of the present invention will be described with reference to Figures 10 to 12. In the following, the description of the same configurations and operations as those of the first and second embodiments will be omitted, and only differences from those embodiments will be described.

[0070] FIG. 10 is a diagram showing the flow of operations in Example 3. A feature of Example 3 that differs from Example 2 is the addition of the processes of steps S110 and S111 in FIG. 10. In step S110, the condition diagnosis unit 16 determines whether the effect of the part replacement is equal to or less than a predetermined threshold. Specifically, if the effect of the part replacement is equal to or less than the predetermined threshold ("Yes" in step S110), the condition diagnosis unit 16 proceeds to step S111, and otherwise ("No" in step S110), the condition diagnosis unit 16 returns to step S101.

[0071] In step S111, the condition diagnosis unit 16 outputs a determination that an abnormality occurred during part replacement to the output control unit 17. The output control unit 17 then displays the determination on the user interface 18. Thus, the third embodiment is characterized in that it determines whether or not an abnormality occurred during part replacement work based on the degree of effectiveness of the part replacement.

[0072] Figure 11 is a diagram illustrating the performance of the part to be replaced (oil filter 9 before replacement), the replacement part (oil filter 9 after replacement), and the diagnostic part (oil cooler 7). Figure 11 is similar to Figure 8. Figure 11 differs from Figure 8 in that it assumes that the performance of the replaced part after replacement will be significantly reduced compared to the performance of the replaced part due to installation errors, installation defects, initial defects, etc. when replacing the part.

[0073] In Figure 11, following the procedure shown in Example 2, the condition diagnosis unit 16 estimates that the performance of the replaced part (oil filter 9) after part replacement is 100%. In fact, this estimation is incorrect. That is, the condition diagnosis unit 16 overestimates the estimated value of the performance of the replaced part relative to the true value (<1>). On the other hand, the condition diagnosis unit 16 significantly underestimates the performance of the diagnosed part (oil cooler 7) by the amount of the overestimation of the performance of the replaced part (<2>). The reason for this is as follows.

[0074] Deterioration of the replacement part and deterioration of the diagnostic part are both reflected in the same way, for example, as an increase in the measurement value of the sensor 23. If the performance of one part is underestimated, the performance of the other part will be overestimated. Similarly, if the deterioration of one part (its contribution to temperature rise) is overestimated, the deterioration of the other part (its contribution to temperature rise) will be underestimated. In other words, as described above, if T is given in the equation "T = F(As, Bs)", As and Bs are in a trade-off relationship.

[0075] The condition diagnosis unit 16 estimates that the performance of the diagnosed part before the part replacement is in the same state as in <2>. Therefore, the condition diagnosis unit 16 again underestimates the estimated value of the performance of the diagnosed part before the part replacement relative to the true value (<3>). Finally, the condition diagnosis unit 16 estimates the condition of the part to be replaced (the oil filter 9 removed upon replacement). At this time, since the performance of the diagnosed part is underestimated, the condition diagnosis unit 16 overestimates the estimated performance of the part to be replaced (<4>).

[0076] The above process reveals the change in performance of the replacement part before and after part replacement, as shown in Example 2. In the case shown in the example of Figure 11, the performance of the replaced part, which should have deteriorated, may be equivalent to or even superior to the performance of the replacement part. Therefore, for example, if the performance of the replaced part is higher and the difference between the performance of the replaced part and the performance of the replacement part exceeds a predetermined threshold, there is a possibility that some kind of problem has occurred with the replacement work or the replacement part itself after replacement. In this case, the user can make a decision, such as performing the replacement work again.

[0077] This makes it possible to measure unintended performance degradation due to defects in the replacement work, and prevents situations such as a reduction in the amount of oil supplied due to an abnormality in the oil filter 9, which would impair the reliability of the sliding parts of the device 14 being diagnosed, thereby achieving further desirable effects in addition to the effects achieved up to Example 2.

[0078] 12 shows an example of the display of the user interface 18 (18a, 18b). The user interface 18 outputs whether or not there is an abnormality in the replaced part. For example, the user interface 18 displays that an abnormality has been detected in the replacement of the oil filter 9 using the above-mentioned mechanism. This allows the user to immediately notice the abnormality during diagnostic operation after the replacement work, and avoids resuming operation while the abnormality is still present, which would impair the performance and reliability of the equipment. The results may be output as an electronic file, on paper, or as a lamp or sound indicating an abnormality, etc.

[0079] FIG. 13 is a block diagram of a computer 980. The equipment status diagnosis devices shown in FIGS. 2 and 6 include one or more computers 980 shown in FIG. 13. In FIG. 13, the computer 980 includes a CPU 981, a storage unit 982, a communication I / F (interface) 983, an input / output I / F 984, and a media I / F 985. The storage unit 982 includes a RAM 982a, a ROM 982b, and an SSD (Solid State Drive) 982c. The communication I / F 983 is connected to a communication circuit 986. The input / output I / F 984 is connected to an input / output device 987. The media I / F 985 reads and writes data from a recording medium 988. The ROM 982b stores an IPL (Initial Program Loader) executed by the CPU, etc. The SSD 982c stores application programs, various data, etc. The CPU 981 executes application programs and the like loaded from the SSD 982c to the RAM 982a to realize various functions. The status diagnosis unit 16, output control unit 17, UI 18, information processing unit 20, and the like of the device status diagnosis device shown in Fig. 2 are primarily blocks showing functions realized by application programs and the like. The same is true for the device status diagnosis device shown in Fig. 6.

[0080] (Effects of the Embodiments) (1) The equipment status diagnosis device can diagnose the deterioration of a diagnosis part that is rarely replaced. (2) The equipment status diagnosis device can separately diagnose the deterioration of a diagnosis part and a replacement part, even when the deterioration of the replacement part and the deterioration of the diagnosis part appear as an increase or decrease in the same sensor. (3) The equipment status diagnosis device can diagnose the deterioration of a diagnosis part when the replacement part and the diagnosis part are in the same system. (4) The equipment status diagnosis device can diagnose a gas compressor. (5) The equipment status diagnosis device can diagnose a gas compressor that has a heat exchanger and a filter.

[0081] (6) The equipment status diagnosis device can be located away from the equipment to be diagnosed. (7) The equipment status diagnosis device can output the replacement time and replacement cost of the diagnosed part. (8) The equipment status diagnosis device can also diagnose the deterioration of the replaced part. (9) The equipment status diagnosis device can output the performance improvement effect of the replaced part. (10) The equipment status diagnosis device can output the presence or absence of an abnormality in the replaced part.

[0082] The present invention is not limited to the above-described embodiments, but includes various modifications. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those including all of the described configurations. Furthermore, it is possible to replace part of the configuration of one embodiment with the configuration of another embodiment, or to add the configuration of another embodiment to the configuration of one embodiment. Furthermore, it is possible to add, delete, or replace part of the configuration of each embodiment with other configurations.

[0083] DESCRIPTION OF SYMBOLS 4 Compression mechanism section 7 Oil cooler (diagnosis part) 9 Oil filter (replacement part, part to be replaced) 13 Equipment status diagnosis device 14 Diagnosis target device (gas compressor, oil-lubricated air screw compressor) 16 Status diagnosis section 17 Output control section 18 User interface (UI) 20 Information processing section 21 Characteristics database (characteristic DB) 23 Sensor

Claims

1. An equipment status diagnosis device comprising: a sensor for measuring the status of an equipment to be diagnosed; a status diagnosis unit for diagnosing the status of parts constituting the equipment to be diagnosed based on measurement values ​​of the sensor; an information processing unit for outputting performance data of a replacement part which is to be replaced among the parts to the status diagnosis unit; and an output control unit for displaying the status of the parts; wherein after the replacement part is replaced, when the equipment to be diagnosed is operated, the status diagnosis unit diagnoses the performance of the diagnostic part which is not to be replaced among the parts using the performance data and the measurement values ​​of the sensor, and the output control unit displays the diagnosis results of the diagnostic part.

2. The equipment status diagnosis device according to claim 1, wherein the direction of increase or decrease in the measurement value of the sensor when deterioration occurs in the diagnostic part is the same as the direction of increase or decrease in the measurement value of the sensor when deterioration occurs in the replacement part.

3. The equipment status diagnosis device according to claim 1, wherein the replacement part and the diagnosis part are connected in terms of the flow of fluid, electricity or heat.

4. The equipment status diagnosis device according to claim 1, wherein the device to be diagnosed is a gas compressor.

5. An equipment status diagnosis device according to claim 4, characterized in that the diagnostic part is a heat exchanger, and the replacement part is a filter for removing solid impurities from a fluid.

6. An equipment status diagnosis device according to claim 1, characterized in that at least a part of the elements constituting said equipment status diagnosis device is separated at a location away from said diagnosis target equipment via a communication network.

7. The equipment status diagnosis device according to claim 1, wherein the diagnosis result includes at least one of the replacement timing of the diagnosed part, the replacement cost, the economic effect of replacing the diagnosed part, and the environmental load reduction effect.

8. The equipment status diagnosis device according to claim 1, wherein the status diagnosis unit diagnoses the performance of the replacement part, and the output control unit displays the diagnosis results of the replacement part.

9. The equipment status diagnosis device according to claim 1, wherein the status diagnosis unit calculates a performance improvement effect resulting from the replacement of the replacement part, and the output control unit displays the performance improvement effect.

10. The equipment status diagnosis device according to claim 1, wherein the status diagnosis unit determines whether or not there is an abnormality in the replacement part, and the output control unit displays whether or not there is an abnormality.

11. An equipment status diagnosis method using an equipment status diagnosis device comprising: a sensor for measuring the status of an equipment to be diagnosed; a status diagnosis unit for diagnosing the status of parts constituting the equipment to be diagnosed based on the measurement values ​​of the sensor; an information processing unit for outputting performance data of a replacement part which is to be replaced among the parts to the status diagnosis unit; and an output control unit for displaying the status of the parts, wherein after replacement of the replacement part is replaced, when the equipment to be diagnosed is operated, the status diagnosis unit diagnoses the performance of the diagnostic part which is not to be replaced among the parts using the performance data and the measurement values ​​of the sensor, and the output control unit displays the diagnosis result of the diagnostic part.

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