Instrument condition diagnosis device and instrument condition diagnosis method

Abstract

To appropriately measure the performance of each component constituting an instrument using information from the same type of a sensor, by utilizing an opportunity to replace a specific component constituting the instrument.SOLUTION: An instrument condition diagnosis device includes: a sensor that measures the condition of a diagnosis target device; a condition diagnosis unit that diagnoses the condition of components constituting the diagnosis target device on the basis of a measurement value from the sensor; an information processing unit that outputs performance data of a replacement component being a replacement target among the components to the condition diagnosis unit; and an output control unit that displays the condition of the components. After the replacement of the replacement component, when the diagnosis target device is operated, the condition diagnosis unit diagnoses the performance of diagnostic components which are not the replacement targets among the components by using the performance data and the measurement value of the sensor. The output control unit displays the diagnosis results of the diagnostic components.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a device state diagnosis apparatus and a device state diagnosis method for diagnosing a device composed of a plurality of components and performing component replacement by maintenance.

Background Art

[0002] Recently, in response to the circular economy that promotes resource circulation from the perspective of resource conservation, it has been required to partially replace the components of a device that has deteriorated over a long period of use and then continue to use the device. In order to replace the components at an appropriate timing, it is necessary to estimate their deterioration state. As one method, it is conceivable to acquire the state of components during operation from sensors incorporated in the device.

[0003] As a technique for determining the presence or absence of an abnormality from sensor information, for example, Patent Document 1 discloses "a shut-off valve control system having a shut-off valve, an air cylinder for rotationally controlling the valve shaft of the shut-off valve, and a solenoid valve for supplying and exhausting air from an air supply source to the cylinder of the air cylinder, and a control means for controlling the opening degree of the shut-off valve, the system comprising a pressure sensor for detecting the internal pressure of the cylinder, a determination means for determining the normality / abnormality of the system based on the pressure characteristics of the internal pressure of the cylinder 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 a storage means for storing in advance the pressure characteristics of the internal pressure of the cylinder during the initial normal operation of the system and the pressure characteristics of the failure prediction boundary, the determination means determining that the system is normal when the actually measured pressure characteristics are within the range between the pressure characteristics during normal operation and the pressure characteristics of the failure prediction boundary, and determining that the system is abnormal when 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 shut-off valve control system detects the internal pressure of the air cylinder by dividing it into three periods: "until the start of operation of the air cylinder", "from the start of operation of the air cylinder to the start of operation of the shut-off valve", and "after the start of operation of the shut-off valve". Then, based on the value of the internal pressure in each period, the shut-off valve control system detects abnormalities in the solenoid valve, air cylinder, and shut-off valve, respectively.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The shut-off valve control system of Patent Document 1 is composed of many components such as a shut-off valve, a solenoid valve, and an air cylinder. On the other hand, as a sensor, it has only one pressure sensor for detecting the internal pressure of the air cylinder. The shut-off valve control system assumes that the force transmission is one-way and time-dependent (stepwise) like "solenoid valve → air cylinder → shut-off valve". Further, Patent Document 1 does not distinguish each of the solenoid valve, air cylinder, and shut-off valve into components that should be frequently replaced and other components, and does not mention diagnosing the deterioration of other components by using the timing of replacing a certain component.

[0007] However, when any of a plurality of components connected to each other in a flow path or the like in a cyclic and simultaneous manner deteriorates, the output of the sensor may fluctuate in the same tendency at the same time. In that case, it becomes difficult to determine from only the sensor information how much each component has deteriorated. As a result, the state estimation accuracy is greatly reduced. If a sensor is added, these determinations become possible, but additional costs are required. Therefore, an object of the present invention is to appropriately measure the performance of each component constituting a device by using the opportunity to replace a certain component constituting the device, based on information from the same type of sensor.

Means for Solving the Problem

[0008] The device state diagnosis apparatus of the present invention includes a sensor that measures the state of a device to be diagnosed, a state diagnosis unit that diagnoses the state of components constituting the device to be diagnosed based on the measurement values of the sensor, an information processing unit that outputs performance data of replacement components, which are components to be replaced among the components, to the state diagnosis unit, and an output control unit that displays the state of the components. After replacing the replacement components, when operating the device to be diagnosed, the state diagnosis unit diagnoses the performance of diagnostic components that are not replacement components among the components using the performance data and the measurement values of the sensor, and the output control unit displays the diagnosis result of the diagnostic components. Other means will be described in the embodiments for carrying out the invention.

Advantages of the Invention

[0009] According to the present invention, by utilizing the opportunity to replace a certain component constituting a device, the performance of each component constituting the device can be appropriately measured based on information from the same type of sensor.

Brief Description of the Drawings

[0010]

Figure 1

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Embodiments for Carrying Out the Invention

[0011] (Basic Concept) Hereinafter, Examples 1 to 3 of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram for explaining the basic concept common to Examples 1 to 3. First, pay attention to the upper diagram of FIG. 1. The upper diagram of FIG. 1 shows a certain circulation system, and the circulation system has a replacement part 9, a diagnostic part 7, and a sensor 23. These are connected by pipes through which the circulating agent circulates. The arrow indicates the direction in which the circulating agent flows. This direction may be reversed. The circulating agent may be in the gas phase, liquid phase, or a mixture thereof. Generally, the replacement part 9 and the diagnostic part 7 may be in a connection relationship in 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, hereinafter, an example in which the sensor 23 measures temperature will be described.

[0012] Note that the part to be replaced among the parts constituting the device to be diagnosed is the replacement part 9. Also, the part that is not a replacement part among the parts constituting the device to be diagnosed is the diagnostic part 7. In this embodiment, the performance of the diagnostic part 7, which is not a part to be replaced, among the parts is diagnosed using the performance data and the measured values of the sensor 23. More specifically, in this embodiment, the performance of the diagnostic part 7 is diagnosed by using "the performance data of the replacement part 9" and "the state of the device to be diagnosed measured by the sensor 23 (the measured values of the sensor 23)" and regarding the part that is not a part to be replaced as the diagnostic part 7.

[0013] The replacement part 9 is a part that is replaced with a new one at a relatively short cycle. The diagnostic part 7 is a part that is replaced at a sufficiently long cycle compared to the replacement part 9. The sensor 23 measures the temperature of the circulating agent in time series. 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 the part is new, the performance is "100%". When the part is completely consumed and can no longer perform its function, the performance is "0%".

[0014] Now, 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 decreases, the temperature of the circulating agent rises, and the measured value of the temperature sensor 23 also rises. When the diagnostic part 7 deteriorates and its performance decreases, the temperature of the circulating agent rises, and the sensor measured value also rises. Thus, the deterioration of the replacement part 9 and the deterioration of the diagnostic part 7 both appear as an increase 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: "true value" and "estimated value". Among these, the "true value" is a value that can only be known after the manufacturer, designer, etc. of the part perform strict analysis. The manufacturer, etc. often take the part back to the factory, etc. and measure the true value using special analysis machines. Conversely, the user of the device including 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 based on the sensor measured value at the site.

[0016] Next, pay attention to the central figure in FIG. 1. A plurality of ●31 are drawn in a three-dimensional space having the performance (%) of the replacement part, the performance (%) of the diagnostic part, and the sensor measured value (°C) as axes. These plurality of ●31 are the results drawn after the manufacturer, etc. conducted experiments in their own factories. That is, the performance of the diagnostic part is the true value Ar, and the performance of the replacement part is also the true value Br. The manufacturer, etc. analyze these relationships.

[0017] Furthermore, pay attention to the lower diagram of FIG. 1. The state diagnosis unit of the equipment state diagnosis device creates a regression surface 32 such that the sum of the squares of the distances from each ●31 in the central diagram of FIG. 1 is minimized. The lower diagram of FIG. 1 shows the result. In the lower diagram of FIG. 1, for simplicity, the regression surface 32 is shown as a plane. The closer the regression surface 32 is to the origin, the higher it is located. That is, as the performance of the replacement part deteriorates, the sensor measurement value increases, and even if the performance of the diagnostic part deteriorates, the sensor measurement value also increases.

[0018] If such a regression surface 32 is prepared, the state diagnosis unit can calculate an estimated value of the performance of the diagnostic part as an unknown value based on the sensor measurement value as a known value and the performance of the replacement part. Similarly, an estimated value of the performance of the replacement part as an unknown value can be calculated based on the sensor measurement value as a known value and the performance of the diagnostic part.

[0019] Now, assume 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 diagnostic 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 the sensor measurement value at time point p immediately before replacing the replacement part 9 with a new one be Tp, and after replacing the replacement part 9 with a new one, when the operation of the device including the part is restarted and the sensor measurement value stabilizes, let the sensor measurement value at time point q be Tq. In many cases, “Tp > Tq” holds.

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

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

[0023] The state diagnosis unit thus estimates the performance of one of the replacement part or the diagnostic part using the function F. However, when a value higher (lower) than the true value is input as the known performance of one side to the state diagnosis unit, it outputs a value lower (higher) than the true value as the unknown performance of the other side. When the regression surface 32 in the lower figure of FIG. 1 is cut by a horizontal section passing through the sensor measurement value Tp, a curve appears on the horizontal section. This curve shows the combination of Aus and Bs such that the sensor measurement value becomes Tp. The larger Aus is, the smaller Bs becomes. Also, if Aus is larger (smaller) than the true value of the performance of the removed replacement part, Bs becomes smaller (larger) than the true value of the performance of the diagnostic part (described later in Example 3).

[0024] Examples 1 to 3 are examples in which the equipment state diagnosis device diagnoses the deterioration of the diagnostic target device as an oil-fed air screw compressor. However, the present invention is widely applicable to a diagnostic target device having both a replacement part 9 replaced at a relatively short cycle and a diagnostic part 7 used for a longer period without being replaced, for performing state diagnosis using the same type of sensor.

[0025] <Example 1> Example 1 of the present invention will be described with reference to FIGS. 2 to 6. FIG. 2 is a diagram showing the overall configuration of the equipment state diagnosis device in Example 1. The equipment state diagnosis device 13 includes a sensor 23, a state diagnosis unit 16, an output control unit 17, a user interface (UI) 18, an information processing unit 20, and a characteristic database (DB) 21. Separately from the equipment state diagnosis device 13, there is a diagnostic target device 14.

[0026] The device state diagnosis apparatus 13 diagnoses the apparatus 14 to be diagnosed. The sensor 23 generally measures the state of the apparatus 14 to be diagnosed, but in the first embodiment, it measures the temperature inside the apparatus 14 to be diagnosed. The apparatus 14 to be diagnosed includes a replacement part 9 and a diagnostic part 7. The diagnostic part 7 is physically connected to the replacement part 9, for example, by a flow path or the like. When the replacement part 9 deteriorates, the measured value (°C) of the sensor 23 increases. Even when the diagnostic part 7 deteriorates, the measured value of the sensor 23 increases.

[0027] The replacement part 9 in FIG. 2 corresponds to the oil filter 9 in FIG. 3. The diagnostic part 7 in FIG. 2 corresponds to the oil cooler 7 in FIG. 3. The applicable range of the present invention is not limited to the case where the sensor 23 is single. The state diagnosis unit 16 outputs the result of diagnosing the deterioration state of the components of the apparatus 14 to be diagnosed using the measured value of the sensor 23 to the output control unit 17. The user interface 18 is a component that exchanges information with the user, and performs information input from the user and information output to the user, for example, on a screen.

[0028] The information processing unit 20 outputs the component replacement information received from the user interface 18 to the state diagnosis unit 16. Further, the information processing unit 20 reads out the replacement part performance data from the characteristic database (DB) 21 and outputs it to the state diagnosis unit 16. The state diagnosis unit 16 performs deterioration diagnosis of the components using the replacement part performance data, and outputs the result to the output control unit 17. The output control unit 17 outputs the result diagnosed by the state diagnosis unit 16 to the user interface 18.

[0029] (Configuration as a microcomputer) The device state diagnosis apparatus 13 includes a microcomputer (not shown) inside. This microcomputer includes a central control device, a main storage device, and an auxiliary storage device. The auxiliary storage device stores the characteristic database 21. The state diagnosis unit 16, the output control unit 17, and the information processing unit 20 are programs. The central control device realizes the functions (information processing) described in advance in each program by reading these programs from the auxiliary storage device to the main storage device.

[0030] Figure 3 is a diagram showing the detailed structure of the device 14 to be diagnosed. The power supply 1, the inverter 2, and the motor 3 are electrically connected. The compression mechanism 4 includes a male rotor, a female rotor, a casing, a shaft 19, etc. The motor 3 and the male side 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, and the air in the compression mechanism 4 is compressed. That is, the device 14 to be diagnosed in Figure 3 (excluding the sensor 23) is a gas compressor (oil-injected 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 Figure 1). Further downstream of the sensor 23, a separator tank 5 is provided. The downstream side of the separator tank 5 branches into two channels, an air flow path and a lubricating oil flow path. The air flow path is connected to an aftercooler 12, which is a heat exchanger for cooling the compressed air. Further downstream of the aftercooler 12, an air tank and pneumatic equipment (not shown) outside the device 14 to be diagnosed are provided.

[0032] On the other hand, an oil cooler 7 (corresponding to the diagnostic component 7 in Figure 1), which is a heat exchanger for cooling the lubricating oil, is provided downstream of the separator tank 5 on the lubricating oil flow path. The downstream of the oil cooler 7 is connected to an oil filter 9 (corresponding to the replacement component 9 in Figure 1). The downstream of the oil filter 9 is connected to the compression mechanism 4 again. The oil cooler 7 is provided in the same space adjacent to the aftercooler 12, and a cooler fan 8 is provided in the flow path connecting to that space.

[0033] The suction filter 10 is arranged between a pipe (not shown) connected to the outside air and the compression mechanism 4 to remove foreign matters such as dust from the inhaled air. The suction throttle valve 11 is arranged on the downstream side of the suction filter 10 and adjusts the amount of inhaled air by controlling its opening degree. The downstream side of the suction throttle valve 11 is connected to the compression chamber in the compression mechanism 4.

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

[0035] During the compression stroke, lubricating oil cooler than the compressed air is supplied, the heated air is cooled, and the gaps between the rotors and the like are sealed to prevent leakage. Thereafter, the compressed air and lubricating oil that have become high temperature and high pressure are discharged into the separator tank 5 on the downstream side. The compressed air and lubricating oil that have flowed into the separator tank 5 in a mixed state are guided 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 and is sufficiently cooled, and then is discharged into an air tank or the like.

[0036] On the other hand, the lubricating oil is separated from the compressed air in the separator tank 5 and stored downward. Thereafter, the oil cooler 7 located on the downstream side of a path different from that of the air cools the lubricating oil to a low temperature. The cooled lubricating oil passes through an oil filter 9 that removes solid impurities in the fluid, and then is supplied again to the compression chamber in the compression mechanism section 4. At this time, since the pressure in the compression chamber where the oil is supplied is lower than the discharge pressure (≈ the internal pressure of the separator tank 5), oil supply is performed by the differential pressure.

[0037] At this time, there is a possibility that a small amount of moisture, dirt, etc. in the air may be mixed into the lubricating oil. Due to this, dirt gradually adheres to the wall surface of the lubricating oil flow path of the oil cooler 7. Then, the thermal resistance gradually increases after long-term use, and the cooling performance of the heat exchanger deteriorates.

[0038] Next, the cooling in the aftercooler 12 and the oil cooler 7 will be described. Both of these heat exchangers are air-cooled. The cooling air generated by the cooler fan 8 passes between the cooling fins on the surface 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 on the downstream side of the aftercooler 12 and the oil cooler 7 with respect to the direction of the flow of the cooling air.

[0039] The cooling air passing through the aftercooler 12 and the oil cooler 7 is supplied by drawing the air around the device 14 to be diagnosed into the housing of the device 14 to be diagnosed. At this time, if dust is contained in the air around the device 14 to be diagnosed, the dust collides with the surfaces of the cooling fins of the aftercooler 12 and the oil cooler 7 together with the cooling air by the cooler fan 8 and gradually adheres. When dust adheres to the surface of the cooling fins, the thermal resistance increases and the cooling performance of the heat exchanger deteriorates.

[0040] As described above, the cooling performance of the device 14 to be diagnosed gradually deteriorates after long-term use, and so-called aging deterioration occurs. Originally, the aftercooler 12 and the oil cooler 7 are not parts that are replaced every time during normal regular maintenance. However, from the perspective of circular economy that continuously uses equipment to reduce resources, these parts must be replaced when the degree of deterioration is large.

[0041] However, since the degree of deterioration varies greatly depending on the usage environment, it is important to estimate the degree of deterioration in individual equipment and replace it at an appropriate timing. In particular, in deterioration diagnosis, if the state of parts can be estimated from sensor information or the like without stopping the equipment in operation, it is possible to avoid impairing the economic efficiency of the user due to the suspension of production activities accompanying the equipment stop for diagnosis.

[0042] As described above, when the cooling performance of the oil cooler 7 deteriorates, the lubricating oil that has been heated to a high temperature by cooling the air in the compression mechanism section 4 cannot be sufficiently cooled, and the outlet temperature of the oil cooler 7 rises. Since the lubricating oil with the increased temperature is supplied to the compression mechanism section 4 again, the temperature of the air and lubricating oil discharged from the compression mechanism section 4 rises, and the sensor 23 measures it.

[0043] Accordingly, when the temperature measured by the sensor 23 is high despite the same operating state, it can be estimated that the oil cooler 7 has deteriorated. For example, by separately constructing a heat transfer analysis model of this equipment and calculating the thermal resistance of the oil cooler 7 at that temperature, the quantitative degree of deterioration of the oil cooler 7 can be estimated. Or, the quantitative degree of deterioration of the oil cooler 7 can also be estimated by obtaining in advance the relationship between the temperature rise of the sensor 23 and the deterioration state (thermal resistance) of the oil cooler 7 through experiments or the like.

[0044] On the other hand, as a result of the oil filter 9 provided in the lubricating oil circulation path capturing dirt particles and the like, when the flow resistance of the oil filter 9 increases, the oil supply amount supplied to the compression mechanism section 4 decreases due to the pressure difference. When the oil supply amount decreases, the compression mechanism section 4 cannot sufficiently cool the air heated by compression. As a result, the temperature at the outlet of the compression mechanism section 4 measured by the sensor 23 rises.

[0045] Therefore, when either the thermal resistance of the oil cooler 7 increases or the flow resistance of the oil filter 9 increases, the temperature measured by the sensor 23 rises. Based on this sensor information, it is difficult to determine which of the oil cooler 7 and the oil filter 9 is deteriorated and to what extent. In particular, the replacement cost of the oil cooler 7 is higher than that of the oil filter 9, and it is necessary to plan the replacement of the oil cooler 7 (and the integrated aftercooler 12) more carefully. Nevertheless, the low prediction accuracy of planning this replacement has been an inhibiting factor for realizing the circular economy.

[0046] Therefore, in Example 1, paying attention to the fact that the oil filter 9 is replaced with a new one by regular maintenance, an appropriate and highly accurate state estimation of the oil cooler 7 is performed.

[0047] FIG. 4 is a diagram showing the flow of operations in Example 1. In step S101, the device 14 to be diagnosed performs normal operation. In step S102, the state diagnosis unit 16 acquires sensor measurement values during the normal operation of the device 14 to be diagnosed from the sensor 23 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 state diagnosis unit 16 determines whether or not a predetermined component replacement time has elapsed. Specifically, when the predetermined component replacement time has elapsed (step S103 “Yes”), the process proceeds to step S104, and in other cases (step S103 “No”), the process returns to step S101.

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

[0050] As the first process in step S106, the information processing unit 20 accepts that the user has input that the component replacement has been performed via the user interface 18, and further accepts the input of the performance of the new replacement component as “replacement component performance data”. The user acquires in advance the performance of the oil filter 9 in a new state through experiments or the like.

[0051] As a second process in step S106, the information processing unit 20 receives, via the user interface 18, an input indicating that the user performs a diagnostic operation for diagnosing the diagnostic component 7 (oil cooler 7) of the device to be diagnosed 14. Thereafter, the information processing unit 20 reads out the replacement part performance data from the characteristic database 21 and outputs it to the state diagnosis unit 16. Then, the state diagnosis unit 16 assumes 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 state 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 an operation by the user.

[0052] Thereafter, when the device to be diagnosed 14 is started and the measured value of the sensor 23 stabilizes, the state diagnosis unit 16 performs a state diagnosis of the diagnostic component 7 using the sensor history data (measured value of the sensor 23) and the replacement part performance data (performance of the new oil filter 9). More specifically, the state diagnosis unit 16 solves the equation "Tq = F(Ans, Bs)" and calculates the unknown Bs. At this time, since the performance Ans of the oil filter 9 is determined, the state diagnosis unit 16 can accurately estimate the performance of the oil cooler 7 (diagnostic component 7 in FIG. 1) from the measured 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 or the like).

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

[0055] Note that the output control unit 17 is not limited to the example of FIG. 5, and may display the performance of the oil cooler 7 in specific numerical values (such as the ratio Bs of the performance to a new product) or may display the replacement timing that can be estimated from the progress rate of deterioration. Further, the output control unit 17 may display the cost required for replacement, the economic effect due to replacement (the amount obtained by converting the efficiency improvement due to deterioration prevention into money), etc., or may display the environmental load reduction effect associated with replacement, such as the greenhouse gas emission reduction effect. Also, the output control unit 17 is not limited to output to a display, and may output as an electronic file or may output to paper.

[0056] According to the first embodiment, when a deterioration state that is difficult to discriminate from sensor information occurs in both the oil cooler 7 that is not normally replaced frequently and the oil filter 9 that is replaced regularly, these deterioration states can be discriminated and accurately estimated. Further, according to the first embodiment, an appropriate replacement plan can be established for components with high replacement costs such as the oil cooler 7, and the economic value and environmental value for the user are improved.

[0057] FIG. 6 is a diagram showing another overall configuration of the device state diagnosis apparatus in the first embodiment. As shown in FIG. 6, a part of the elements constituting the device state diagnosis apparatus 13 may be installed separately at a remote location with respect to the device under diagnosis 14. At this time, the side of the device under diagnosis 14 is called an edge unit 13a, and the part existing at a remote location of the edge unit 13a via the communication network 22 is called a server unit 13b. The edge unit 13a and the server unit 13b can transmit and receive data via the communication network 22, and can exhibit the functions described in the first embodiment in substantially the same manner as when all the components are in the same location as shown in FIG. 2.

[0058] Furthermore, by aggregating the state diagnosis unit 16 with a large computational load in the server unit 13b and increasing the information processing ability of the server unit 13b, it is possible to perform state estimation at high speed while suppressing the cost of the edge unit 13a including the device under diagnosis 14.

[0059] <Second Embodiment> Example 2 of the present invention will be described with reference to FIGS. 7 to 9. In the following, the description of the same configuration and operation as in Example 1 will be omitted, and the differences from Example 1 will be described. FIG. 7 is a diagram showing the flow of operations in Example 2. A feature of Example 2 different from Example 1 is that the processes in steps S108 and S109 in FIG. 7 are added.

[0060] In step S108, the information processing unit 20 receives, via the user interface 18, an input indicating that the user performs a diagnostic operation for diagnosing the component to be replaced (the oil filter 9 before replacement) of the diagnostic target device 14. Thereafter, the state diagnosis unit 16 performs a state diagnosis of the component to be replaced using the sensor history data (measurement values of the sensor 23). More specifically, the state diagnosis unit 16 solves the equation "Tp = F(Aus, Bs)" and calculates the unknown Aus.

[0061] In step S109, the state diagnosis unit 16 calculates the performance improvement effect by replacing the replacement component 9 and outputs it to the output control unit 17. Then, the output control unit 17 displays the performance improvement effect via the user interface 18. Thus, the feature of Example 2 lies in estimating the performance of the component to be replaced, that is, the oil filter 9 removed by the replacement work in the regular maintenance.

[0062] FIG. 8 is a diagram for explaining the performance of the component to be replaced (the oil filter 9 before replacement), the replacement component (the oil filter 9 after replacement), and the diagnostic component (the oil cooler 7). The vertical axis in FIG. 7 represents the performance of the component to be replaced, the replacement component, and the diagnostic component. Specifically, the performance is, for example, the cooling performance of the oil cooler 7 (diagnostic component) and the flow rate with respect to the pressure difference of the oil filter 9 (replacement component or component to be replaced). The reference "100%" is the performance of a new product state without deterioration of each component.

[0063] For each of the diagnostic part and the part to be replaced before part replacement, and the diagnostic part and the replacement part after part replacement, there is a set of bar graphs showing "performance (true value)" and bar graphs showing "performance (estimated value)". The user cannot know the true value on site. The estimated value is the performance estimated by the state diagnosis unit 16 using the function F.

[0064] As described in the first embodiment, immediately after replacing the replacement part, the state diagnosis unit 16 assumes that "the performance of the replacement part is the same as the performance data of the replacement part at the time of new product obtained in advance". At this time, it is estimated that the performance of the replacement part has recovered to 100% (<1>). When the state of the replacement part is determined, the state diagnosis unit 16 can accurately estimate the performance of the diagnostic part (oil cooler 7) based on the value of the sensor 23 as shown in <2>.

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

[0066] As described above, the state diagnosis unit 16 can accurately estimate the performance (degree of deterioration) of both the part to be replaced before part replacement and the replacement part after part replacement. Therefore, the state diagnosis unit 16 can quantitatively show how much change (effect) has been obtained by part replacement by comparing these.

[0067] FIG. 9 is a display example 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 numerically shows the performance improvement result of the oil filter 9 due to the replacement of the oil filter 9. Note that, similar to the case of the first embodiment, the output format may be electronic data or may be output on paper. Further, since the deterioration rate can be estimated from the degree of performance degradation and its period, the user interface 18 may display a guideline for the next replacement time and the like.

[0068] By doing as described above, it is possible to accurately estimate not only the performance after component replacement but also the performance before component replacement retrospectively. In addition to the effects shown in the first embodiment, by presenting the user with the effects of the component replacement itself, the next replacement time of the replacement component, etc., it is possible to obtain the effect on the replacement cost. Thereby, by promoting component replacement at an appropriate timing and maintaining the performance of the device, the economic value and environmental value for the user can be improved.

[0069] <Example 3> The third embodiment of the present invention will be described with reference to FIGS. 10 to 12. Hereinafter, the description of the same configuration and operation as those in the first embodiment and the second embodiment will be omitted, and the differences from them will be described.

[0070] FIG. 10 is a diagram showing the flow of operations in the third embodiment. The feature of the third embodiment different from the second embodiment is that the processes of steps S110 and S111 in FIG. 10 are added. In step S110, the state diagnosis unit 16 determines whether or not the effect of component replacement is equal to or less than a predetermined threshold value. Specifically, when the effect of component replacement is equal to or less than a predetermined threshold value (step S110 “Yes”), the state diagnosis unit 16 proceeds to step S111, and in other cases (step S110 “No”), it returns to step S101.

[0071] In step S111, the state diagnosis unit 16 outputs to the output control unit 17 that it has determined that an abnormality has occurred during component replacement. Thereafter, the output control unit 17 displays this fact on the user interface 18. As described above, the feature of the third embodiment lies in determining the presence or absence of an abnormality in the component replacement operation according to the degree of the effect of component replacement.

[0072] FIG. 11 is a diagram for explaining the performance of the component to be replaced (oil filter 9 before replacement), the replacement component (oil filter 9 after replacement), and the diagnostic component (oil cooler 7). FIG. 11 is similar to FIG. 8. The difference between FIG. 11 and FIG. 8 is that it is assumed that due to a failure in mounting, a defect in mounting, an initial defect of the replacement component, etc. during component replacement, the performance of the replacement component after component replacement is significantly lower than the performance of the replacement component before component replacement.

[0073] Also in FIG. 11, according to the procedure shown in the second embodiment, the state diagnosis unit 16 estimates that the performance of the replacement component (oil filter 9) after component replacement is 100%. In fact, this estimation is incorrect. That is, the state diagnosis unit 16 will overestimate the estimated value of the performance of the replacement component with respect to the true value ((1)). On the other hand, the state diagnosis unit 16 will significantly underestimate the performance of the diagnostic component (oil cooler 7) by the amount by which it overestimates the performance of the replacement component ((2)). The reason for this is as follows.

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

[0075] The state diagnosis unit 16 estimates that the performance of the diagnostic component before component replacement is in the same state as <2>. Therefore, the state diagnosis unit 16 also underestimates the estimated value of the performance of the diagnostic component before component replacement with respect to the true value (<3>). The state diagnosis unit 16 finally estimates the state of the component to be replaced (the oil filter 9 removed by replacement). At this time, since the performance of the diagnostic component is underestimated, the state diagnosis unit 16 overestimates the estimated performance of the component to be replaced (<4>).

[0076] By the above processing, the performance change of the replacement component before and after component replacement becomes clear as shown in Example 2. In the case shown in the example of FIG. 11, the performance of the component to be replaced that should originally have decreased may be equal to or higher than the performance of the replacement component. Therefore, for example, when the performance of the component to be replaced is higher and the difference obtained by subtracting the performance of the replacement component from the performance of the component to be replaced exceeds a predetermined threshold value, there may be some defect in the replacement operation or the replacement component itself after replacement. At this time, the user can make a judgment such as re-performing the replacement operation.

[0077] Thereby, it is possible to measure an unintended performance degradation due to a defect in the replacement operation, prevent the oil supply amount from being reduced due to an abnormality of the oil filter 9 and impairing the reliability of the sliding part of the diagnostic target device 14, and obtain a more preferable effect in addition to the effects up to Example 2.

[0078] FIG. 12 is a display example of the user interface 18 (18a, 18b). The user interface 18 outputs whether there is an abnormality in the replacement component. The user interface 18 displays, for example, that an abnormality has been detected in the replacement of the oil filter 9 by the above mechanism. By this, the user immediately notices an abnormality in the diagnostic operation after the replacement operation and avoids resuming the operation in an abnormal state and impairing the performance and reliability of the device. The result output method may be an electronic file, paper output, a lamp indicating an abnormality, a sound, or the like.

[0079] FIG. 13 is a block diagram of computer 980. The device state diagnostic apparatus shown in FIGS. 2 and 6 includes one or more computers 980 shown in FIG. 13. In FIG. 13, 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. Here, storage unit 982 includes a RAM 982a, a ROM 982b, and an SSD (Solid State Drive) 982c. Communication I / F 983 is connected to a communication circuit 986. Input / output I / F 984 is connected to an input / output device 987. Media I / F 985 reads and writes data from / to a recording medium 988. The ROM 982b stores an IPL (Initial Program Loader) and the like executed by the CPU. The SSD 982c stores application programs, various data, and the like. The CPU 981 realizes various functions by executing application programs and the like read from the SSD 982c into the RAM 982a. The state diagnostic unit 16, output control unit 17, UI 18, information processing unit 20, etc. of the device state diagnostic apparatus shown in FIG. 2 above are mainly shown as blocks of functions realized by application programs and the like. The same applies to the device state diagnostic apparatus shown in FIG. 6.

[0080] (Effects of the Embodiment) (1) The device state diagnostic apparatus can diagnose the deterioration of diagnostic parts with few replacement opportunities. (2) The device state diagnostic apparatus can also diagnose the deterioration of diagnostic parts and replacement parts separately even when the deterioration of replacement parts and diagnostic parts appears in the same increasing or decreasing direction of the sensor. (3) The device state diagnostic apparatus can diagnose the deterioration of diagnostic parts when the replacement parts and diagnostic parts are within the same system. (4) The device state diagnostic apparatus can diagnose a gas compressor. (5) The device state diagnostic apparatus can diagnose a gas compressor having a heat exchanger and a filter.

[0081] (6) The device status diagnostic apparatus can be arranged separately from the apparatus to be diagnosed. (7) The device status diagnostic apparatus can output the replacement timing, replacement cost, etc. of diagnostic components. (8) The device status diagnostic apparatus can also diagnose the deterioration of replacement parts. (9) The device status diagnostic apparatus can output the performance improvement effect of replacement parts. (10) The device status diagnostic apparatus can output the presence or absence of abnormalities in replacement parts.

[0082] Note that the present invention is not limited to the above-described embodiments and includes various modifications. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Also, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, or replace other configurations for a part of the configuration of each embodiment.

Explanation of Reference Numerals

[0083] 4 Compression mechanism section 7 Oil cooler (diagnostic component) 9 Oil filter (replacement part, part to be replaced) 13 Device status diagnostic apparatus 14 Apparatus to be diagnosed (gas compressor, oil-injected air screw compressor) 16 Status diagnostic section 17 Output control section 18 User interface (UI) 20 Information processing section 21 Characteristic database (characteristic DB) 23 Sensor

Claims

1. A sensor that measures the state of a device to be diagnosed, A state diagnosis unit that diagnoses the state of components constituting the device to be diagnosed based on the measurement values of the sensor, An information processing unit that outputs performance data of replacement parts, which are the parts to be replaced among the components, to the state diagnosis unit, An output control unit that displays the state of the components, comprising When the device to be diagnosed is operated after replacing the replacement parts, the state diagnosis unit diagnoses the performance of diagnostic parts that are not replacement parts among the components using the performance data and the measurement values of the sensor, and the output control unit displays the diagnosis result of the diagnostic parts, A device state diagnosis apparatus characterized by the above.

2. The direction of increase or decrease in the measurement value of the sensor when deterioration occurs in the diagnostic parts is the same as the direction of increase or decrease in the measurement value of the sensor when deterioration occurs in the replacement parts, The device state diagnosis apparatus according to claim 1, characterized by the above.

3. The replacement parts and the diagnostic parts are in a connection relationship in a fluid, electrical, or thermal flow, The device state diagnosis apparatus according to claim 1, characterized by the above.

4. The device to be diagnosed is a gas compressor, The device state diagnosis apparatus according to claim 1, characterized by the above.

5. The diagnostic parts are heat exchangers, and the replacement parts are filters that remove solid impurities from fluids, The device state diagnosis apparatus according to claim 4, characterized by the above.

6. At least a part of the elements constituting the device state diagnosis apparatus is separated at a location away from the device to be diagnosed via a communication network, The device state diagnosis apparatus according to claim 1, characterized in that.

7. The diagnosis result includes at least one of the replacement timing, replacement cost, economic effect when replaced, and environmental load reduction effect of the diagnosis parts, The device state diagnosis apparatus according to claim 1, characterized in that.

8. The state diagnosis unit diagnoses the performance of the replacement parts, The output control unit displays the diagnosis result of the replacement parts, The device state diagnosis apparatus according to claim 1, characterized in that.

9. The state diagnosis unit calculates the performance improvement effect due to the replacement of the replacement parts, The output control unit displays the performance improvement effect, The device state diagnosis apparatus according to claim 1, characterized in that.

10. The state diagnosis unit judges the presence or absence of abnormality of the replacement parts, The output control unit displays the presence or absence of the abnormality, The device state diagnosis apparatus according to claim 1, characterized in that.

11. A sensor for measuring the state of the device to be diagnosed, A state diagnosis unit for diagnosing the state of the parts constituting the device to be diagnosed based on the measured values of the sensor, An information processing unit for outputting the performance data of the replacement parts, which are the parts to be replaced among the parts, to the state diagnosis unit, An output control unit for displaying the state of the parts, A device state diagnosis method by a device state diagnosis apparatus including When operating the device to be diagnosed after replacing the replacement part, The state diagnosis unit Diagnoses the performance of diagnostic parts that are not replacement targets among the parts using the performance data and the measured values of the sensors, The output control unit Displays the diagnosis result of the diagnostic part, A device state diagnosis method characterized by the above.

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