Fault diagnosis system and fault diagnosis method for work machine

Abstract

The present application easily determines a failure of a component mounted on a work machine. A controller acquires time-series data detected in a first period as first snapshot data, and acquires time-series data detected in a second period later than the first period as second snapshot data. Information in which a deviation of a physical quantity for monitoring an operation state of the component from a normal range is associated with a failure of the component as a cause of the deviation is stored in a storage. The controller determines the failure of the component based on the first snapshot data, the second snapshot data, and the information stored in the storage.

Description

Technical Field

[0001] This disclosure relates to a fault diagnosis system and method for operating machinery. Background Technology

[0002] Japanese Patent Application Publication No. 2016-151086 (Patent Document 1) discloses an excavator support device in which time-series data representing the operating status of the excavator under diagnosis is compared with typical time-series data obtained from a database and displayed on a display device. The aforementioned document describes that by comparing the time-series data of the excavator under diagnosis with typical time-series data, an abnormality can be visually confirmed when the excavator under diagnosis exhibits an abnormality.

[0003] Prior art literature

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2016-151086 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] Sometimes, even after obtaining and analyzing a single time series data point, it is difficult to determine the true cause of the failure.

[0008] This disclosure provides a fault diagnosis system and method for operating machinery that can easily determine the failure of components.

[0009] Methods for solving problems

[0010] According to one aspect of this disclosure, a fault diagnosis system for operating machinery is proposed. The fault diagnosis system includes components mounted on the operating machinery, a detection unit that detects predetermined physical quantities to monitor the operating status of the components, a controller, and a storage unit. The controller acquires time-series data of the physical quantities detected within a predetermined period as snapshot data. The controller determines whether the physical quantities detected by the detection unit are within the normal range. The storage unit stores information obtained by correlating deviations of the physical quantities from the normal range with component faults as the cause of such deviations. The controller acquires time-series data detected within a first period as first snapshot data. The controller acquires time-series data detected within a second period, which is later than the first period, as second snapshot data. Based on the first snapshot data, the second snapshot data, and the information stored in the storage unit, the controller determines the component fault.

[0011] According to one aspect of this disclosure, a fault diagnosis method for operating machinery is proposed. The operating machinery includes components and a detection unit that detects predetermined physical quantities to monitor the operational status of the components. Information obtained by associating deviations of the physical quantities detected by the detection unit from their normal ranges with component faults that may be the cause of such deviations is stored in a storage unit. The fault diagnosis method includes the following steps: In a first step, time-series data of the physical quantities detected within a first period is acquired as first snapshot data. In a second step, time-series data of the physical quantities detected within a second period, which is later than the first period, is acquired as second snapshot data. In a third step, based on the first snapshot data, the second snapshot data, and the information stored in the storage unit, a component fault is determined.

[0012] Invention Effects

[0013] According to the fault diagnosis system and fault diagnosis method disclosed herein, faults in components mounted on operating machinery can be easily determined. Attached Figure Description

[0014] Figure 1 This is a diagram that schematically illustrates the structure of a working machine based on an embodiment of the present disclosure.

[0015] Figure 2 This is a system diagram of the engine's cooling system.

[0016] Figure 3 This is a block diagram illustrating the structure of the system based on the implementation method.

[0017] Figure 4 This is a schematic diagram illustrating the first example of a database of fault causes.

[0018] Figure 5 This is a schematic diagram illustrating the second example of a database of fault causes.

[0019] Figure 6 It is a graph of snapshot data when each physical quantity is within the normal range.

[0020] Figure 7 This is a graph of the first example of snapshot data when a physical quantity deviates from its normal range.

[0021] Figure 8 This is a second example of snapshot data when a physical quantity deviates from its normal range.

[0022] Figure 9 This is the third example of snapshot data when a physical quantity deviates from its normal range.

[0023] Figure 10 This is the fourth example of snapshot data when a physical quantity deviates from its normal range.

[0024] Figure 11 This is the fifth example of snapshot data when a physical quantity deviates from its normal range.

[0025] Figure 12 This is a flowchart illustrating the process of handling faults in a component based on an implementation method.

[0026] Figure 13 This is a snapshot of data taken at a point in time after the fault occurred.

[0027] Figure 14 This is a block diagram illustrating the system architecture based on the second embodiment.

[0028] Figure 15 This is a block diagram illustrating the system architecture based on the third embodiment. Detailed Implementation

[0029] The embodiments will now be described based on the accompanying drawings. In the following description, the same reference numerals will be used to denote the same parts. Their names and functions are also the same. Therefore, detailed descriptions of them will not be repeated.

[0030] [First Implementation Method]

[0031] <Overall Structure of the Operating Machinery>

[0032] Figure 1 This is a side view that schematically illustrates the structure of a hydraulic excavator 1, an example of a working machine based on an embodiment of this disclosure. Figure 1 As shown, the hydraulic excavator 1 mainly comprises a traveling body 2, a slewing body 3, and a working device 4. The traveling body 2 and the slewing body 3 constitute the body of the hydraulic excavator 1.

[0033] The traveling body 2 has a pair of tracks, one on the left and one on the right. The hydraulic excavator 1 moves by driving the pair of tracks to rotate.

[0034] The slewing body 3 is configured to rotate freely relative to the traveling body 2. The slewing body 3 mainly comprises a cab 7, an engine compartment 5, and a counterweight 6. The cab 7 is located, for example, on the front left side of the slewing body 3. The operator of the hydraulic excavator 1 sits in the cab 7. Inside the cab 7 is a driver's seat for the operator. The engine compartment 5 is located at the rear of the slewing body 3 relative to the cab 7. The engine compartment 5 houses the engine unit (engine 10, exhaust system, etc., described later). The counterweight 6 is located at the rear of the engine compartment 5.

[0035] The working device 4 is mounted on the front side of the rotating body 3. The working device 4 is located, for example, on the right side of the cab 7. The working device 4 can be driven by a hydraulic cylinder. Through this drive, the working device 4 can rotate up and down relative to the rotating body 3.

[0036] <Structure of the Cooling System>

[0037] Figure 2 This is a system diagram of the cooling system for engine 10. Engine 10 is mounted on... Figure 1 The rotating body 3 is shown. The engine 10 is housed within the engine compartment 5. The cooling system of the engine 10 includes a cooling water circulation path 20 for circulating cooling water. The cooling water pump 22, water jacket 21A, thermostat 24, and radiator 26 are connected sequentially via cooling water piping 21. The cooling water pressurized by the cooling water pump 22 flows sequentially through the water jacket 21A, thermostat 24, and radiator 26. Figure 2 The arrows along the cooling water circulation path 20 indicate the direction of cooling water flow.

[0038] The cooling water pump 22 is driven by the driving force generated by the engine 10, and pumps cooling water. The water jacket 21A is a flow path for the cooling water located inside the engine 10, such as inside the cylinder block and cylinder head. Heat generated inside the engine 10 is transferred to the cooling water flowing in the water jacket 21A, thereby cooling the engine 10. The cooling water that has received heat from the engine 10 is cooled in the radiator 26 through heat exchange with the air. The cooling water cooled by the radiator 26 returns to the cooling water pump 22.

[0039] The thermostat 24 controls the temperature of the coolant within the engine 10. When the coolant temperature within the engine 10 is low, the thermostat 24 is closed, and coolant does not flow to the radiator 26. By creating a flow path for coolant that circulates only within the engine 10, the temperature of the engine 10 is promoted to rise. When the coolant temperature within the engine 10 is high, the thermostat 24 is open, and coolant flows to the radiator 26. The coolant cooled by the radiator 26 circulates back to the engine 10, thereby cooling the engine 10 through heat dissipation to the coolant.

[0040] A coolant reservoir 28 is connected to the radiator 26. A portion of the coolant is stored in the coolant reservoir 28. By appropriately flowing coolant from the radiator 26 to the coolant reservoir 28, or in the opposite direction, an appropriate amount of coolant can be circulated in the coolant circulation path 20.

[0041] exist Figure 2 The diagram also illustrates a working oil circulation path 30 for circulating working oil. In this example, working oil refers to the oil supplied to the hydraulic actuator 40 to enable it to operate. The hydraulic actuator 40 includes, for example, a hydraulic cylinder for driving the working device 4, a rotary motor for rotating the rotating body 3 relative to the traveling body 2, and a travel motor for driving the traveling body 2.

[0042] The working oil pump 32, main valve 34, oil cooler 36, and working oil tank 38 are connected in sequence via working oil piping 31. The working oil pressurized by the working oil pump 32 flows sequentially through the main valve 34, oil cooler 36, and working oil tank 38. Figure 2 The arrows along the working oil circulation path 30 indicate the direction of working oil flow.

[0043] Working oil is stored in the working oil tank 38. The working oil pump 32 is connected to the output shaft 12 of the engine 10 and receives the driving force generated by the engine 10 via the output shaft 12. The working oil pump 32 is driven by the driving force of the engine 10 and pumps the working oil in the working oil tank 38 to the main valve 34.

[0044] A spool valve (not shown) is built into the main valve 34. The main valve 34 controls the flow rate and direction of the working oil supplied to each hydraulic actuator 40 by moving the spool valve axially. The working oil returning from the hydraulic actuators 40 to the main valve 34 is cooled in the oil cooler 36 by heat exchange with air. The working oil cooled by the oil cooler 36 returns to the working oil tank 38.

[0045] A bypass valve 37 is installed on the working oil pipe 31 between the main valve 34 and the oil cooler 36. The bypass valve 37 supplies a portion of the working oil to the oil cooler 36 to cool it, and returns the remaining working oil directly to the working oil tank 38 instead of supplying it to the oil cooler 36. When the working oil temperature is low, the resistance to the flow of the working oil increases, and fuel consumption decreases. By adjusting the amount of working oil cooled by the oil cooler 36 through the bypass valve 37, the temperature of the working oil is appropriately controlled.

[0046] A cooling fan 16 is connected to the output shaft 11 of the engine 10. The cooling fan 16 is driven to rotate by the driving force of the engine 10 via the output shaft 11, thereby generating airflow through the radiator 26 and the oil cooler 36. The radiator 26 cools the coolant by dissipating heat to the airflow generated by the cooling fan 16. The oil cooler 36 cools the working oil by dissipating heat to the airflow generated by the cooling fan 16. The radiator 26 and the oil cooler 36 are arranged adjacent to each other. The radiator 26 and the oil cooler 36 may also be arranged side-by-side in the direction of airflow generated by the cooling fan 16.

[0047] A fan clutch 18 is provided on the output shaft 11 of the engine 10. The cooling fan 16 is connected to the engine 10 via the fan clutch 18. The fan clutch 18 can adjust the speed of the cooling fan 16. When the engine speed, coolant temperature, and oil temperature are relatively low, and the need for cooling by the coolant and oil is less, such as immediately after starting the engine 10, the transmission of driving force from the engine 10 to the cooling fan 16 is reduced, thereby reducing noise and minimizing losses incurred in driving the cooling fan 16. As the engine speed increases and the coolant and oil temperatures rise, the fan clutch 18 becomes fully engaged, transmitting driving force to the cooling fan 16 and increasing its speed, thereby promoting cooling of the coolant and oil.

[0048] <Inspection Department 60>

[0049] exist Figure 2 The cooling system shown is equipped with a detection unit 60 for detecting specified physical quantities. The detection unit 60 includes a water temperature sensor 61, an oil temperature sensor 62, a fan speed sensor 63, a water level sensor 64, a fuel injection quantity sensor 65, and an engine speed sensor 66.

[0050] Water temperature sensor 61 detects the temperature of the cooling water. The cooling water temperature is used to monitor the operation of the cooling fan 16, cooling water pump 22, thermostat 24, and radiator 26. Oil temperature sensor 62 detects the temperature of the working oil. The working oil temperature is used to monitor the operation of the cooling fan 16, working oil pump 32, oil cooler 36, and bypass valve 37. Fan speed sensor 63 detects the speed of the cooling fan 16. The speed of the cooling fan 16 is used to monitor its operation. Furthermore, the speed of the cooling fan 16 is controlled by controller 50 based on the temperatures detected by water temperature sensor 61 and oil temperature sensor 62.

[0051] A water level sensor 64 detects the coolant level in the reservoir 28. The coolant level in the reservoir 28 is used to monitor the operation of the reservoir 28 and the various devices constituting the coolant circulation path 20. A fuel injection quantity sensor 65 detects the amount of fuel supplied to the engine 10. The amount of fuel supplied to the engine 10 is used to monitor the operation of the engine 10. An engine speed sensor 66 detects the engine speed of the engine 10. The engine speed of the engine 10 is used to monitor the operation of the engine 10.

[0052] The detection unit 60 also includes an outside air temperature sensor 67. The outside air temperature sensor 67 detects the outside air temperature near the cooling system. The outside air temperature sensor 67 is used to detect the temperature of the air supplied to the radiator 26 and the oil cooler 36.

[0053] The aforementioned engine 10, cooling fan 16, cooling water circulation circuit 20, cooling water pump 22, thermostat 24, radiator 26, reservoir 28, working oil pump 32, oil cooler 36, and bypass valve 37 are components mounted in a hydraulic excavator 1, which is an example of a working machine. The detection unit 60 detects specified physical quantities to confirm the operating status of the components. Detection signals representing the physical quantities detected by each detection unit 60 are input to the controller 50.

[0054] Figure 2 The water temperature sensor 61 shown is located inside the engine 10, but the water temperature sensor 61 can also be configured at any location in the cooling water circulation path 20. Figure 2 The oil temperature sensor 62 shown is located in the working oil tank 38, but the oil temperature sensor 62 can also be located at any position in the working oil circulation path 30.

[0055] <Structure of Controller 50>

[0056] Figure 3 This is a block diagram illustrating the structure of a system based on an implementation method. For example... Figure 3 As shown, the controller 50 includes a work control unit 50A, a physical quantity acquisition unit 50B, a status judgment unit 50C, a snapshot data acquisition unit 50D, an arithmetic processing unit 50E, and a storage unit 50F.

[0057] Figure 3 The operating device 52 shown accepts operation from the operator to start the hydraulic excavator 1. The operating device 52 is located, for example, inside the cab 7. The operating device 52 is, for example, an engine key switch. The work control unit 50A receives an input from the operating device 52 indicating that the operator has operated the operating device 52, and generates an instruction signal to operate the hydraulic excavator 1. Control signals are output from the controller 50 to each component, thereby causing the components to operate. For example, an instruction signal is output from the work control unit 50A to the engine 10, and the engine 10 starts.

[0058] Physical quantity acquisition section 50B from reference Figure 2 Each of the described detection units 60 receives an input signal representing the physical quantity detected by the detection unit 60.

[0059] The snapshot data acquisition unit 50D generates time-series data for each physical quantity based on the physical quantities detected by the detection unit 60 and input to the physical quantity acquisition unit 50B. The snapshot data acquisition unit 50D acquires snapshot data, which is a summary of the time-series data of multiple physical quantities detected within a specified period. It should be noted that the acquired snapshot data is stored in the storage unit 50F, but is either deleted or updated with newly acquired snapshot data after a specified period. Details of the snapshot data will be described later.

[0060] The status determination unit 50C determines whether each physical quantity detected by the detection unit 60 and input to the physical quantity acquisition unit 50B is within the normal range or deviates from the normal range. The status determination unit 50C can determine whether each physical quantity is within the normal range based on snapshot data.

[0061] The snapshot data acquisition unit 50D acquires the time series data of the physical quantity detected within a specified period, traced back from the time point at which the status judgment unit 50C determines that any physical quantity deviates from the normal range after the operation control unit 50A generates the indication signal, as the initial snapshot data. The initial snapshot data is stored in the storage unit 50F.

[0062] When the status determination unit 50C determines that any physical quantity deviates from the normal range, the processing unit 50E, based on the snapshot data acquired by the snapshot data acquisition unit 50D, determines the component failure that is the cause of the deviation of the physical quantity from the normal range. A failure cause database 50FDB is stored in the storage unit 50F. The failure cause database 50FDB includes information that associates deviations of physical quantities from the normal range with failures of components that are the cause of the deviation. The processing unit 50E reads the failure cause database 50FDB from the storage unit 50F and determines one or more component failures that are the cause of a specific physical quantity deviating from the normal range.

[0063] The fault cause database 50FDB also includes information that associates component failures with countermeasures for those failures. The processing unit 50E outputs countermeasures for component failures determined as the cause of deviations in physical quantities from their normal range. The processing unit 50E displays, for example, the countermeasures for component failures on a monitor 54. The monitor 54 is, for example, located inside the cab 7. The monitor 54 is, for example, located in front of the operator's seat. The operator of the hydraulic excavator 1, seated in the cab 7, can identify component failures and corresponding countermeasures by viewing the display on the monitor 54.

[0064] Figure 3 The functional modules of the controller 50 shown do not necessarily need to be implemented by a single controller. They can also be implemented by combining multiple controllers, each including a portion of a functional module. Figure 3 The controller 50 shown. For example, the physical quantity acquisition unit 50B and the arithmetic processing unit 50E can also be constructed from different hardware.

[0065] <Fault Cause Database 50FDB>

[0066] Figure 4 This is a schematic diagram illustrating the first example of the fault cause database 50FDB. Figure 4 The fault tree is shown in the diagram. Figure 4 In the fault tree, the event for which the object is identified is the overheating of the coolant in engine 10. Overheating of the coolant in engine 10 corresponds to an example of the physical quantity described above deviating from the normal range.

[0067] Overheating of the engine 10's coolant can be determined by the coolant temperature deviating from the normal range, as detected by the water temperature sensor 61. Alternatively, the engine speed of the engine 10, as detected by the engine speed sensor 66, can deviate from the normal range and the engine output of the engine 10 decreases, which can also be used to assist in determining the occurrence of overheating.

[0068] Overheating of the coolant occurs due to insufficient cooling of the coolant or excessive heat generation of the engine 10.

[0069] Insufficient cooling water heat dissipation occurs due to insufficient cooling water volume, poor cooling water circulation, insufficient airflow to the radiator 26 for heat dissipation from the cooling water, or high temperature of the airflow to the radiator 26 for heat dissipation from the cooling water.

[0070] A deficiency in cooling water volume is determined by detecting a deviation of the cooling water level in the reservoir 28 from the normal range, as detected by the water level sensor 64.

[0071] Insufficient cooling water volume occurs due to cooling water leakage or evaporation. Cooling water leakage may occur in the cooling water piping 21, the reservoir 28, or the radiator 26. Cooling water evaporation may occur in the radiator 26. Therefore, in this case, the faulty component is identified as any one of the cooling water piping 21, the reservoir 28, and the radiator 26. Events of such faults, including cooling water leakage or evaporation in the cooling water piping 21, the reservoir 28, or the radiator 26, along with visual inspections as countermeasures against these faults, are stored in the storage unit 50F.

[0072] Poor cooling water circulation occurs due to a malfunction in the cooling water pump 22 or the thermostat 24.

[0073] A malfunction occurs in the cooling water pump 22, and in this case, the component that has failed is identified as the cooling water pump 22. Such a malfunction event as the cooling water pump 22 failure, the replacement of the cooling water pump 22 as a countermeasure against the malfunction, and the confirmation of the effectiveness of the replacement are stored in the storage unit 50F in a related manner.

[0074] A malfunction occurs in the thermostat 24, and in this case, the faulty component is identified as the thermostat 24. Such a malfunction event as the thermostat 24 malfunction, the replacement of the thermostat 24 as a countermeasure against the malfunction, and confirmation of the effectiveness of the replacement are stored in the storage unit 50F in association.

[0075] Insufficient airflow for cooling water dissipation occurs due to insufficient speed of the cooling fan 16 or blockage of the heat dissipation surface of the radiator 26. Hereinafter, blockage of the radiator 26 means that the heat dissipation surface of the radiator 26 is blocked.

[0076] Insufficient airflow can be determined by detecting that the speed of the cooling fan 16 deviates from the normal range, as detected by the fan speed sensor 63. Alternatively, the simultaneous occurrence of overheating of both the cooling water and the working oil, when the working oil temperature detected by the oil temperature sensor 62 deviates from the normal range, can also be used to assist in determining the occurrence of insufficient airflow.

[0077] Insufficient speed of cooling fan 16 occurs due to malfunction of cooling fan 16 or malfunction of fan clutch 18. In this case, the faulty component is identified as cooling fan 16 or fan clutch 18. The event of malfunction of cooling fan 16, along with the inspection, replacement, and confirmation of the effectiveness of the replacement of cooling fan 16 as a countermeasure against the malfunction, are stored in the storage unit 50F. The event of malfunction of fan clutch 18, along with the inspection, replacement, and confirmation of the effectiveness of the repair of fan clutch 18 as a countermeasure against the malfunction, are stored in the storage unit 50F.

[0078] If blockage occurs in the radiator 26, the malfunctioning component is identified as the radiator 26. The event of such a malfunction as blockage of the radiator 26, along with visual inspection and cleaning of the radiator 26 as countermeasures against the malfunction, are stored in the storage unit 50F.

[0079] The high temperature of the air coming into contact with the radiator 26 to dissipate heat from the cooling water is related to the high outside air temperature. A high outside air temperature is determined by the deviation of the outside air temperature detected by the outside air temperature sensor 67 from the normal range. The operator can confirm the cause of this adverse situation by visually viewing the outside air temperature displayed on the monitor 54.

[0080] Excessive heat generation in engine 10 is caused by excessive fuel injection into engine 10, or by high resistance or load generated in engine 10.

[0081] The excessive fuel injection into the engine 10 is determined by detecting that the amount of fuel supplied to the engine 10 deviates from the normal range by the fuel injection quantity sensor 65.

[0082] Excessive fuel injection into engine 10 occurs due to malfunction of the injection pump 14 installed in the fuel supply system to engine 10. In this case, the malfunctioning component is identified as injection pump 14. The event of such malfunction of injection pump 14, the inspection and replacement of injection pump 14 as a countermeasure against the malfunction, and the confirmation of the effect of the replacement are stored in the storage unit 50F in a related manner.

[0083] The large resistance generated in the engine 10 is due to defects such as wear or breakage in the engine 10's components, such as the piston or piston connecting rod, resulting in resistance or load. In this case, the faulty component is identified as the piston or piston connecting rod. The events of such faults as piston or piston connecting rod defects, along with the inspection and replacement of the piston and piston connecting rod as countermeasures against the fault, and the confirmation of the effectiveness of the replacement, are stored in the storage unit 50F in a related manner.

[0084] In this way, by analyzing the detection results of the detection unit 60 related to component failure, it is easy to determine the component failure that is the cause of overheating of the engine 10's coolant, and it is easy to grasp the countermeasures against the failure.

[0085] Figure 5 This is a schematic diagram illustrating the second example of the 50FDB fault cause database. (Compared to...) Figure 4 Similarly, in Figure 5 The fault tree is shown in the diagram. Figure 5 In the fault tree, the event that becomes the object is the overheating of the working oil. Overheating of the working oil is equivalent to a deviation of the aforementioned physical quantity from the normal range. The occurrence of working oil overheating is determined by the deviation of the working oil temperature from the normal range detected by the oil temperature sensor 62.

[0086] Overheating of the working oil occurs due to insufficient airflow in contact with the oil cooler 36 for heat dissipation, high temperature of the air in contact with the oil cooler 36 for heat dissipation, or poor circulation of the working oil.

[0087] Insufficient airflow for cooling the working oil occurs due to insufficient speed of the cooling fan 16 or blockage of the heat dissipation surface of the oil cooler 36. Hereinafter, blockage of the oil cooler 36 means that the heat dissipation surface of the oil cooler 36 is blocked.

[0088] Insufficient airflow is determined by the deviation of the cooling fan 16 speed from the normal range detected by the fan speed sensor 63. The insufficient speed of the cooling fan 16 is caused by malfunction of the cooling fan 16 or a malfunction of the fan clutch 18. In this case, the faulty component is identified as either the cooling fan 16 or the fan clutch 18. Events of malfunctions such as cooling fan 16 malfunction, along with the inspection, replacement, and effectiveness confirmation of the cooling fan 16 as countermeasures against the malfunction, are stored in the storage unit 50F. Similarly, events of malfunctions such as fan clutch malfunction, along with the inspection, replacement, and effectiveness confirmation of the fan clutch 18 as countermeasures against the malfunction, are stored in the storage unit 50F.

[0089] If blockage occurs in the oil cooler 36, the component that has failed is identified as the oil cooler 36. Such events as blockage of the oil cooler 36, along with visual inspection and cleaning of the oil cooler 36 as countermeasures against the failure, are stored in the storage unit 50F.

[0090] The temperature of the air that comes into contact with the oil cooler 36 to dissipate heat from the working oil is related to the high outside air temperature. A high outside air temperature is determined by the outside air temperature sensor 67 deviating from the normal range. The operator can confirm the cause of this malfunction by visually viewing the outside air temperature displayed on the monitor 54.

[0091] Poor circulation of working oil occurs due to a malfunction of the working oil pump 32 or the bypass valve 37.

[0092] If a malfunction occurs in the working oil pump 32, the faulty component is identified as the working oil pump 32. Such malfunction events as the working oil pump 32 malfunction, along with the inspection and replacement of the working oil pump 32 as countermeasures against the malfunction, and confirmation of the effectiveness of the replacement, are stored in the storage unit 50F.

[0093] A malfunction occurs in the bypass valve 37, and in this case, the faulty component is identified as the bypass valve 37. Such malfunction events as the bypass valve 37 malfunction, the replacement of the bypass valve 37 as a countermeasure against the malfunction, and the confirmation of the effectiveness of the replacement are stored in the storage unit 50F in a related manner.

[0094] In this way, by analyzing the detection results of the detection unit 60 related to component failure, it is easy to determine the component failure that is the cause of overheating of the working oil, and it is easy to grasp the countermeasures against the failure.

[0095] <Snapshot Data>

[0096] Next, we will explain the snapshot data, which is the data obtained by summarizing the time series data of multiple physical quantities detected within the specified period. Figure 6 It is a graph of snapshot data when each physical quantity is within the normal range.

[0097] exist Figure 6 The accompanying figures, which will be described later, show time-series data of the following physical quantities: cooling water temperature (horizontal axis: time; vertical axis: temperature); operating oil temperature (horizontal axis: time; vertical axis: temperature); outside air temperature (horizontal axis: time; vertical axis: temperature); cooling fan speed 16 speed (horizontal axis: time; vertical axis: speed); engine speed 10 speed (horizontal axis: time; vertical axis: speed); cooling water level in reservoir 28 (horizontal axis: time; vertical axis: water level height); and fuel supply to engine 10 (horizontal axis: time; vertical axis: fuel injection quantity). Each time-series data point shown in a single figure, i.e., a snapshot, represents the time progression of each physical quantity within the same period.

[0098] exist Figure 6 The table shows snapshot data of each physical quantity within its normal range. Specifically, the cooling water temperature is maintained within a range higher than the threshold for opening the thermostat 24 valve and lower than the threshold for the cooling water to become overheated during the specified period. The operating oil temperature is maintained within a range lower than the threshold for the operating oil to become overheated during the specified period, and more specifically, lower than the threshold for maximizing the speed of the cooling fan 16. The outside air temperature is maintained within a range lower than the operating environment limit temperature, for example, 45°C, during the specified period.

[0099] The speed of cooling fan 16 is maintained at nearly maximum speed for a specified period. The speed of engine 10 is maintained at approximately the rated speed at which the driving force generated by engine 10 is at its maximum for a specified period. The water level of coolant in reservoir 28 is maintained at a level that is lower than a threshold that would be considered high and higher than a threshold that would be considered low, and more specifically, slightly lower than a threshold that would be considered high, for a specified period. The fuel injection quantity into engine 10 is maintained at approximately the injection quantity corresponding to the rated rotational speed at which the driving force generated by engine 10 is at its maximum.

[0100] Figure 7 This is a graph of the first example of snapshot data when a physical quantity deviates from its normal range. Figure 7The image shows snapshot data when the coolant temperature and operating oil temperature deviate from the normal range. Specifically, the coolant temperature rises over a specified period, exceeding the threshold for overheating. The operating oil temperature rises over a specified period, exceeding the threshold for maximizing the speed of the cooling fan 16, thus reaching the threshold for overheating.

[0101] The outside air temperature rises slowly over a specified period of time. As the coolant temperature and the working oil temperature reach the overheating threshold, the temperature of the air discharged through the radiator 26 and the oil cooler 36 rises, and thus, the outside air temperature sensor 67 detects an increase in the outside air temperature near the cooling system.

[0102] The time shift of engine speed 10, the time shift of coolant level in reservoir 28, and the time shift of fuel injection quantity into engine 10 are all within the time frame of ... Figure 6 The same applies when the normal range is shown.

[0103] exist Figure 7 In the first example shown, both the cooling water temperature and the working oil temperature reached the threshold of overheating. Figure 4 The reasons for the overheating of the cooling water shown, and Figure 5 The common cause of the overheating of the working oil shown is inferred to be the temperature of both the cooling water and the working oil. In other words, insufficient airflow for heat dissipation from both the cooling water and the working oil is inferred to be the cause of overheating.

[0104] Here, if we refer to the time progression of the cooling fan 16 speed, the speed increases sharply at the moment T when the cooling water temperature reaches the threshold that opens the thermostat 24 valve, thus identifying it as maintaining approximately the maximum speed in the latter half of the specified period. Figure 4 , 5 The insufficient airflow caused by insufficient cooling fan speed 16 was not presumed to be the cause. Therefore, the fault was determined to be a blockage in radiator 26 and oil cooler 36.

[0105] Thus, the arithmetic processing unit 50E ( Figure 3 The processing unit 50E also outputs countermeasures for the component malfunction. In this case, the processing unit 50E outputs a notification to the operator to clean the radiator 26 and oil cooler 36 to remove blockages. For example, the processing unit 50E displays a reminder on the monitor 54 to clean the radiator 26 and oil cooler 36 to remove blockages.

[0106] Figure 8 This is the second example of snapshot data when a physical quantity deviates from its normal range. Figure 8The data also includes snapshots of coolant and oil temperatures deviating from normal ranges. Specifically, the coolant temperature rises over a specified period, exceeding the threshold for overheating. The oil temperature also rises over a specified period, reaching the threshold for overheating.

[0107] The outside temperature remained relatively constant throughout the specified period, but compared to when it was at a certain temperature... Figure 6 The normal range shown is higher. The time shifts of engine speed 10, coolant level in reservoir 28, and fuel injection quantity into engine 10 are related to the time shifts of these parameters. Figure 6 The same applies when the normal range is shown.

[0108] exist Figure 8 In the second example shown, it is also related to Figure 7 Similarly, in the first example shown, the insufficient airflow for cooling from both the cooling water and the working oil was inferred to be the cause of overheating in both the cooling water temperature and the working oil temperature.

[0109] Here, if we refer to the time progression of the cooling fan 16's rotational speed, the speed increases at the moment T when the cooling water temperature reaches the threshold that opens the thermostat 24, but it will not increase to the maximum speed. Throughout the latter half of the specified period, the cooling fan 16's rotational speed is a value between a moderate speed and the maximum speed. Figure 4 , 5 Insufficient airflow is presumed to be caused by insufficient rotational speed of cooling fan 16. Therefore, the fault is determined to be due to malfunction of either cooling fan 16 or fan clutch 18.

[0110] In this way, the processing unit 50E determines the component malfunction. The processing unit 50E also outputs countermeasures for the component malfunction. In this case, the processing unit 50E outputs information such as notifying the operator to inspect and replace the cooling fan 16 and fan clutch 18, and confirming the effectiveness of the replacement. For example, the processing unit 50E displays a reminder on the monitor 54 to inspect, repair, and replace the cooling fan 16 and fan clutch 18, and confirm the subsequent effectiveness.

[0111] Figure 9 This is the third example of snapshot data when a physical quantity deviates from its normal range. Figure 9 The image shows snapshot data when the coolant temperature deviates from the normal range, but the operating oil temperature is balanced. Specifically, the coolant temperature rises over a specified period, exceeding the threshold for overheating. The operating oil temperature is maintained within a range lower than the threshold that causes the cooling fan 16 to reach its maximum speed during the specified period.

[0112] The outside air temperature remains constant throughout the specified period. The speed of the cooling fan 16 increases sharply at the moment T when the coolant temperature reaches the threshold that opens the thermostat 24, and is maintained at approximately maximum speed for the latter half of the specified period. The time progression of the engine 10 speed, the time progression of the coolant level in the reservoir 28, and the time progression of the fuel injection amount into the engine 10 are all related to the time progression of the engine 10 speed. Figure 6 The same applies when the normal range is shown.

[0113] exist Figure 9 In the third example shown, the reason why the working oil temperature remained uniform while only the coolant temperature rose was inferred to be included in Figure 4 The causes of overheating of the cooling water shown are not included in Figure 5 The cause of the overheating of the working oil is shown, as is the specific cause of the overheating of the cooling water. In other words, insufficient airflow and high air temperature are not considered to be the cause of the cooling water overheating. Since the cooling water level in the reservoir 28 has not dropped, insufficient cooling water volume is also not considered a cause. Since the fuel injection is balanced, excessive fuel injection is also not considered a cause. Therefore, the fault event is determined to be poor cooling water circulation.

[0114] In this way, the processing unit 50E determines the component malfunction. The processing unit 50E also outputs countermeasures for the component malfunction. In this case, the processing unit 50E outputs information such as notifying the operator to replace the cooling water pump 22 and the thermostat 24, and confirming the effect of the replacement. For example, the processing unit 50E displays a reminder on the monitor 54 to replace the cooling water pump 22 and the thermostat 24, and confirm the effect of the replacement.

[0115] Figure 10 This is the fourth example of snapshot data when a physical quantity deviates from its normal range. Figure 10 The image also shows snapshot data when the coolant temperature deviates from the normal range but the operating oil temperature is balanced. Specifically, the coolant temperature rises over a specified period, exceeding the threshold for overheating. The operating oil temperature is maintained within a range lower than the threshold that causes the cooling fan 16 to reach its maximum speed during the specified period.

[0116] The outside air temperature remains constant throughout the specified period. The speed of cooling fan 16 increases sharply at the moment T when the coolant temperature reaches the threshold that opens the thermostat 24, and is maintained at approximately maximum speed for the latter half of the specified period. The time shift of engine speed 10, and the time shift of fuel injection quantity into engine 10, are related to the time shift of the engine speed 10. Figure 6 The same applies when the normal range is shown.

[0117] If we refer to the time progression of the cooling water level in the storage tank 28, the cooling water level decreases as time passes within a specified period, further lowering the threshold for a low water level.

[0118] exist Figure 10 In the fourth example shown, the insufficient cooling water volume was presumed to be the cause of overheating of the cooling water because the water level in the reservoir 28 had decreased. Therefore, the fault event was determined to be a leak of cooling water in the cooling water piping 21, the reservoir 28, or the radiator 26, or the evaporation of cooling water in the radiator 26.

[0119] In this way, the processing unit 50E determines the component's malfunction. The processing unit 50E also outputs countermeasures for the component's malfunction. In this case, the processing unit 50E outputs information such as notifying the operator of a visual inspection of the cooling water piping 21, the reservoir 28, and the radiator 26. For example, the processing unit 50E displays a reminder on the monitor 54 to conduct a visual inspection of the cooling water piping 21, the reservoir 28, and the radiator 26.

[0120] Figure 11 This is the fifth example of snapshot data when a physical quantity deviates from its normal range. Figure 11 The image also shows snapshot data when the coolant temperature deviates from the normal range but the operating oil temperature is balanced. Specifically, the coolant temperature rises over a specified period, exceeding the threshold for overheating. The operating oil temperature is maintained within a range lower than the threshold that causes the cooling fan 16 to reach its maximum speed during the specified period.

[0121] The outside air temperature remains constant throughout the specified period. The speed of cooling fan 16 increases sharply at the moment T when the coolant temperature reaches the threshold that opens the thermostat 24, and is maintained at approximately maximum speed for the latter half of the specified period. The time progression of engine speed 10 and the time progression of coolant level in reservoir 28 are related to the time progression of the engine speed 10 and the time progression of coolant level in reservoir 28. Figure 6 The same applies when the normal range is shown.

[0122] If we consider the time progression of the fuel injection quantity to engine 10, the fuel injection quantity exceeds the driving force generated by engine 10, reaching the maximum rated injection quantity. Since the actual fuel injection quantity is greater than the target value, fuel consumption is reduced.

[0123] exist Figure 11 In the fifth example shown, since the fuel injection quantity to engine 10 was greater than the injection quantity corresponding to rated rotation speed, the excessive fuel injection quantity was presumed to be the cause of coolant overheating. Therefore, the fault event was determined to be a malfunction of the injection pump 14.

[0124] In this way, the processing unit 50E determines the component malfunction. The processing unit 50E also outputs countermeasures for the component malfunction. In this case, the processing unit 50E outputs information such as notifying the operator to inspect, repair, and replace the injection pump 14, and confirming the effect afterward. For example, the processing unit 50E displays a visual inspection reminder on the monitor 54 to inspect and replace the injection pump 14, and to confirm the effect after replacement.

[0125] By analyzing the snapshot data of time series data containing multiple physical quantities through the controller 50 (processing unit 50E) as described above, it is possible to determine as early as possible which component of the hydraulic excavator 1 is in a faulty state.

[0126] The processing unit 50E can also use mathematical processing such as smoothing to determine component failures based on snapshot data. Alternatively, the processing unit 50E can also have an artificial intelligence model for determining component failures based on snapshot data. This artificial intelligence model can also be an artificial intelligence model learned using learning data that includes the failures of a certain component and snapshot data obtained when the failure occurred.

[0127] Storage Unit 50F ( Figure 3 The storage unit 50F can also pre-store typical snapshot data as reference snapshot data when a specific component fails. The storage unit 50F can also store multiple reference snapshot data corresponding to various faults. The processing unit 50E, which acquires snapshot data during the operation of the hydraulic excavator 1, can quickly determine component faults by identifying reference snapshot data similar to the acquired snapshot data and reading the faults corresponding to the identified reference snapshot data.

[0128] By storing information that associates the fault state of a component with countermeasures for the cause of the fault in the storage unit 50F, this information can be retrieved from the storage unit 50F when a component fault is determined. Based on this information, countermeasures for the fault can be executed as early as possible, enabling faster recovery from the fault.

[0129] <Determining Component Faults>

[0130] Next, the process of determining the characteristics of component failures based on the embodiments of this disclosure will be described. Figure 12 This is a flowchart illustrating the process of handling faults in a component based on an implementation method.

[0131] like Figure 12 As shown, firstly, preparations are made to pre-store the reference snapshot data in the storage unit 50F (step S1). The reference snapshot data includes... Figure 6 The snapshot data shown indicates that the physical quantities are within the normal range, and also includes... Figures 7-11 The image shows typical snapshot data when a specific component fails.

[0132] The operator uses the operating device 52 ( Figure 3 The controller 50 (work control unit 50A) receives an input from the operating device 52 indicating that the operator has operated the operating device 52, and generates an indication signal for starting the hydraulic excavator 1 (step S2).

[0133] In order to confirm the operating status of the components mounted on the hydraulic excavator 1, the detection unit 60 detects specified physical quantities. The controller 50 (physical quantity acquisition unit 50B) acquires the physical quantities detected by each detection unit 60 from each detection unit 60 (step S3).

[0134] The controller 50 (status determination unit 50C) determines whether each physical quantity detected by the detection unit 60 and input to the physical quantity acquisition unit 50B is within the normal range, or whether the physical quantity deviates from the normal range and the component whose physical quantity is detected is in a fault state (step S4). If it is determined that the component is not in a fault state (no in step S4), the subsequent fault determination process is not executed, and the process of acquiring physical quantities in step S3 is returned.

[0135] If any component is determined to be in a fault state (as in step S4), the controller 50 (snapshot data acquisition unit 50D) generates time-series data of each physical quantity input to the physical quantity acquisition unit 50B, and acquires snapshot data by summarizing the time-series data of multiple physical quantities detected within a specified period. The snapshot data acquired at this time is the time-series data of physical quantities detected within a specified period tracing back from the time point when it was initially determined that the physical quantity deviated from the normal range; this is called the initial snapshot data (step S5). In this case, the initial snapshot data is the time-series data of physical quantities detected from the time point after tracing back the specified period from the time point when it was initially determined that the physical quantity deviated from the normal range, to the time point when it was initially determined that the physical quantity deviated from the normal range.

[0136] Alternatively, the time series data of the physical quantity detected from the time point when it was initially determined that the physical quantity deviated from the normal range until a predetermined period has elapsed can be used as the initial snapshot data. Alternatively, the time series data of the physical quantity detected within a predetermined period including the time point when it was initially determined that the physical quantity deviated from the normal range can also be used as the initial snapshot data. The initial snapshot data corresponds to the first snapshot data of the embodiment. The period during which the time series data of the physical quantity included in the initial snapshot data was detected corresponds to the first period of the embodiment.

[0137] The controller 50 saves the initial snapshot data obtained in step S5 to the storage unit 50F (step S6).

[0138] The data obtained is the summation of time-series data of physical quantities from periods later than the period in which the initial snapshot data was obtained, and is used as the operational snapshot data (step S7). For example, when an operator or repairman who is aware that a component is in a faulty state inputs a signal to the controller 50 to instruct the acquisition of snapshot data by operating the operating device 52, the controller 50 (snapshot data acquisition unit 50D) may also acquire snapshot data from a predetermined period traced back from the time the input was received as the operational snapshot data. In this case, the operational snapshot data is the time-series data of physical quantities detected from a time point after a predetermined period of time has elapsed since the time the controller 50 received the input, up to the time the controller 50 received the input.

[0139] Alternatively, the time-series data of the physical quantities detected from the time the controller 50 receives the input until a predetermined period has elapsed can be used as the operational snapshot data. The time-series data of the physical quantities detected within a predetermined period including the time the controller 50 receives the input can also be used as the operational snapshot data. The operational snapshot data corresponds to the second snapshot data of the embodiment. The period during which the time-series data of the physical quantities included in the operational snapshot data is detected corresponds to the second period of the embodiment.

[0140] It should be noted that after step S6, if none of the physical quantities deviate from the normal range, and if the operator or repairman does not perform any operation on the signal input controller 50 to obtain snapshot data by operating the operating device 52, etc., the processing of step S7 can be skipped.

[0141] While the component determined to be in a faulty state in step S4 remains in a faulty state, the controller 50 may continuously or intermittently acquire snapshot data. The controller 50 may also save the latest acquired snapshot data as operational snapshot data in the storage unit 50F and continue updating the operational snapshot data. Upon receiving instructions from an operator or repair technician, the controller 50 may also read and output the latest operational snapshot data stored in the storage unit 50F.

[0142] Based on the snapshot data during operation, determine whether a component failure can be identified (step S8).

[0143] Figure 13 This is a snapshot of data taken at a point in time, elapsed since the occurrence of the fault. Figure 13During the specified period, the coolant temperature rises until it exceeds the overheating threshold. Similarly, the working oil temperature rises until it reaches the overheating threshold.

[0144] The outside air temperature rises slowly over the specified period. The speed of the cooling fan 16 increases sharply at the moment T when the coolant temperature reaches the threshold that opens the thermostat 24, and is maintained at approximately maximum speed for the latter half of the specified period. The time progression of the engine 10 speed and the time progression of the fuel injection quantity into the engine 10 are related to the time progression of the specified period. Figure 6 The same applies to the normal range shown. If the cooling water level in the reservoir 28 is referenced over time, the cooling water level is lower than the threshold for low water level throughout the entire specified period.

[0145] Figure 13 The operational snapshot data shown has waveforms that differ from those of typical fault occurrence snapshot data contained in the baseline snapshot data, making it difficult to determine component failures based solely on this operational snapshot data.

[0146] If it is determined that a component failure cannot be determined based on the snapshot data during operation (No in step S8), proceed to step S9, where the controller 50 (processing unit 50E) reads the initial snapshot data from the storage unit 50F (step S9). The controller 50 (processing unit 50E) determines the component failure based on the initial snapshot data (step S10).

[0147] For example, if the initial snapshot data stored in storage unit 50F is... Figure 9 If the snapshot data shown is the same, then refer to... Figure 9 As explained, the failure event was determined to be poor cooling water circulation. In this case, at the time of the failure, the cooling water level in the reservoir 28 was slightly below the threshold level that would be considered high, indicating sufficient cooling water flow. Figure 9 The cooling water continues to overheat and evaporate, thus reducing the amount of cooling water. As a result, it is inferred that the cooling water level in the storage tank 28 has decreased. Figure 13 Subsequently, based on the rise in outside air temperature, it was deduced that the working oil had reached overheating.

[0148] For example, if the initial snapshot data stored in storage unit 50F is... Figure 10 If the snapshot data shown is the same, then refer to... Figure 10 As previously explained, insufficient coolant volume was presumed to be the cause of coolant overheating, and the malfunction was identified as a coolant leak or evaporation. Subsequently, the rise in outside air temperature was inferred to be due to overheating of the working oil.

[0149] If a component failure can be determined based on snapshot data during operation (as in step S8), steps S9 and S10 are not performed.

[0150] Next, it is determined whether there are multiple countermeasures for the fault (step S11). For example, based on... Figure 9 Based on the snapshot data shown, if the fault event is determined to be poor cooling water circulation, the causes of the fault are deduced to be either a malfunction of the cooling water pump 22 or a malfunction of the thermostat 24. As countermeasures to the fault, the replacement of the cooling water pump 22 and confirmation of its effectiveness, and the replacement of the thermostat 24 and confirmation of its effectiveness, are deduced. In such cases, it is determined that there are multiple countermeasures to address the fault.

[0151] When it is determined that there are multiple countermeasures for the fault (as in step S11), the countermeasures are assigned a priority (step S12). In the case of poor cooling water circulation, for example, the history of faults and repairs of the cooling water pump 22 and the thermostat 24 is stored in advance as maintenance history information in the storage unit 50F. By reading the maintenance history information, it is possible to determine which component of the cooling water pump 22 and the thermostat 24 is more likely to fail. As a result of this determination, a countermeasure for the fault corresponding to the component with the higher probability of failure is output (step S13). This output is, for example, displayed on the monitor 54 by the controller 50 (processing unit 50E) to show the countermeasure for the component's fault.

[0152] If it is determined that there is only one countermeasure for the fault (not in step S11), the processing in step S12 is not performed, and the countermeasure for the determined fault is output in step S13. Then, the processing ends. Figure 12 (The end).

[0153] <Functions and Effects>

[0154] Although there are some repetitions with the above description, the characteristic structure and effects of this embodiment will be described in a concentrated manner as follows.

[0155] In a fault diagnosis system based on implementation methods, such as Figure 12As shown, component failures are determined based on initial snapshot data and operational snapshot data obtained after the initial snapshot data. In cases where it is difficult to determine component failures based solely on operational snapshot data at a point in time after the failure occurred, component failures can be determined based on initial snapshot data. This makes it easy to identify failures in components mounted on the hydraulic excavator 1. By accurately identifying the cause of the component failure and corresponding countermeasures, and quickly implementing these countermeasures, recovery from the failure can be achieved rapidly. Therefore, downtime of the hydraulic excavator 1 can be reduced, and operational efficiency can be improved.

[0156] like Figure 12 As shown, by using the earlier snapshot data from two snapshot data points separated in the time series as the initial snapshot data immediately after the fault occurred, the component fault can be determined with higher accuracy. By generating an indication signal for operating the hydraulic excavator 1 through the controller 50, the initial snapshot data at the moment the initial fault occurred after the hydraulic excavator 1 was started can be reliably obtained.

[0157] like Figure 12 As shown, by saving the initial snapshot data in the storage unit 50F, when it is difficult to determine the fault of a component based solely on the snapshot data during operation, the saved initial snapshot data can be read and the fault of the component can be determined based on the initial snapshot data.

[0158] like Figure 12 As shown, since the output provides countermeasures for the identified fault, operators or repair personnel can quickly implement countermeasures by referring to the output.

[0159] like Figure 12 As shown, when there are multiple countermeasures for a fault, priority is assigned to output countermeasures. Therefore, operators or repairmen can efficiently execute countermeasures for the fault by referring to this output.

[0160] [Second Implementation]

[0161] In the first embodiment, an example was described where the controller 50 mounted on the work machinery determines component failures based on snapshot data. However, this is not a limited example; a controller located external to the work machinery could also determine component failures. Figure 14 This is a block diagram illustrating the system architecture based on the second embodiment.

[0162] like Figure 14 As shown, the hydraulic excavator 1 is equipped with a detection unit 60 as described in the first embodiment. The controller 50 acquires the physical quantities detected by the detection unit 60. The hydraulic excavator 1 includes a communication unit 56. The communication unit 56 has communication functions such as wireless communication.

[0163] A remote operating device 70 is provided on the exterior of the hydraulic excavator 1. The remote operating device 70 has an operating mechanism (not shown) that is operated by an operator to enable the hydraulic excavator 1 to operate. The operator operates the remote operating device 70 remotely from the work site, away from the hydraulic excavator 1, thereby performing work using the hydraulic excavator 1.

[0164] The communication unit 56 of the hydraulic excavator 1 sends the physical quantities detected by the detection unit 60 to the remote operating device 70. The controller 50 mounted on the hydraulic excavator 1 can also generate time-series data of the physical quantities, i.e., snapshot data. In this case, the communication unit 56 sends the snapshot data to the remote operating device 70.

[0165] The remote operation device 70 includes a fault diagnosis controller 71, a fault cause database 72, a monitor 74, and a communication unit 76. The communication unit 76 receives information sent by the communication unit 56 of the hydraulic excavator 1. The communication unit 76 inputs the received information related to physical quantities into the fault diagnosis controller 71.

[0166] Similar to the fault cause database 50FDB described in the first embodiment, Figure 14 The fault cause database 72 shown contains information that associates deviations of physical quantities from their normal range with faults in components that are the cause of such deviations.

[0167] The fault diagnosis controller 71 receives input of physical quantities from the communication unit 76 and generates snapshot data of the physical quantities. When snapshot data generated by the controller 50 of the hydraulic excavator 1 is sent to the communication unit 76, the fault diagnosis controller 71 receives this snapshot data as input. Similar to the first embodiment, the fault diagnosis controller 71 reads the fault cause database 72 and, based on the snapshot data and the fault cause database 72, determines the fault of one or more components that are the cause of a deviation when a specific physical quantity deviates from its normal range.

[0168] The fault diagnosis controller 71 sends a signal to the monitor 74 displaying the identified component fault and corresponding countermeasures. The operator of the remote control device 70 can identify the component fault and corresponding countermeasures by viewing the display on the monitor 74. Because the component fault and corresponding countermeasures can be accurately identified remotely from the work site far from the hydraulic excavator 1, recovery from the fault can be achieved quickly by rapidly implementing the countermeasures.

[0169] [Third Implementation Method]

[0170] Figure 15This is a block diagram illustrating the system structure based on the third embodiment. Similar to the first embodiment, the hydraulic excavator 1 based on the third embodiment is operated by an operator seated in the cab 7, and includes an operating device 52, a controller 50, and a detection unit 60. The controller 50 generates snapshot data and determines component failures based on the snapshot data. The hydraulic excavator 1 also includes a communication unit 56 as described in the second embodiment.

[0171] The hydraulic excavator 1 is connected to a remote monitoring device 90 and a portable terminal 100 via a network 80.

[0172] A remote monitoring device 90 is installed externally on the hydraulic excavator 1 to remotely monitor the operation and work performed by the hydraulic excavator 1. The remote monitoring device 90 includes a server 91, a monitor 94, and a communication unit 96. The inspector or repairman of the hydraulic excavator 1 carries a portable terminal 100. The portable terminal 100 may be, for example, a smartphone or tablet PC.

[0173] The communication unit 56 of the hydraulic excavator 1 transmits the identified component faults and corresponding countermeasures to the remote monitoring device 90 and the portable terminal 100 via the network 80. The remote monitoring device 90 processes the component faults and countermeasures received by the communication unit 96 in the server 91 and displays them on the monitor 94. The portable terminal 100 displays the received component faults and countermeasures on the screen.

[0174] The operator, who monitors the operation of the hydraulic excavator 1 remotely via the remote monitoring device 90, can identify component malfunctions and corresponding countermeasures by viewing the display on the monitor 74. Inspectors and repair personnel equipped with the portable terminal 100 can also identify component malfunctions and corresponding countermeasures by viewing the display on the portable terminal 100. By accurately identifying component malfunctions and corresponding countermeasures, and quickly implementing these countermeasures, rapid recovery from malfunctions is possible.

[0175] In the above description of the embodiments, a hydraulic excavator 1 was described as an example of a working machine, but the ideas of this disclosure can also be applied to other types of working machines, such as bulldozers, wheel loaders, dump trucks, etc.

[0176] The embodiments disclosed herein should be considered illustrative rather than restrictive. The scope of the invention is defined by the technical solutions rather than by the foregoing description, and is intended to include all modifications of the same meaning and scope.

[0177] Explanation of reference numerals in the attached figures:

[0178] 1…Hydraulic excavator; 2…Traveling body; 3…Slewing body; 4…Working device; 5…Engine compartment; 7…Cab; 10…Engine; 11, 12…Output shaft; 14…Jet pump; 16…Cooling fan; 18…Fan clutch; 20…Cooling water circulation circuit; 21…Cooling water piping; 21A…Water jacket; 22…Cooling water pump; 24…Thermostat; 26…Radiator; 28…Reservoir; 30…Working oil circulation circuit; 31…Working oil piping; 32…Working oil pump; 34…Main valve; 36…Oil cooler; 37…Bypass valve; 38…Working oil tank; 40…Hydraulic actuator; 50…Controller; 50A…Working control unit; 50B…Physical quantity acquisition unit; 50C...Status Judgment Unit; 50D...Snapshot Data Acquisition Unit; 50E...Arithmetic Processing Unit; 50F...Storage Unit; 50FDB, 72...Fault Cause Database; 52...Operating Device; 54, 74, 94...Monitor; 56, 76, 96...Communication Unit; 60...Detection Unit; 61...Water Temperature Sensor; 62...Oil Temperature Sensor; 63...Fan Speed ​​Sensor; 64...Water Level Sensor; 65...Fuel Injection Quantity Sensor; 66...Engine Speed ​​Sensor; 67...Outdoor Air Temperature Sensor; 70...Remote Operating Device; 71...Fault Diagnosis Controller; 80...Network; 90...Remote Monitoring Device; 91...Server; 100...Portable Terminal.

Claims

1. A failure diagnosis system of a work machine, wherein the failure diagnosis system of the work machine comprises: a component mounted on the work machine; a detection unit that detects a prescribed physical quantity in order to monitor an operation state of the component; a controller that acquires time series data of the physical quantity detected within a prescribed period as snapshot data, and judges whether the physical quantity detected by the detection unit is within a normal range; and a storage unit that stores information associating a deviation of the physical quantity from the normal range with a failure of the component as a cause of the deviation, the controller acquires the time series data detected within a first period as first snapshot data, the controller acquires the time series data detected within a second period later than the first period as second snapshot data, the controller judges whether a failure of the component can be determined based on the second snapshot data and the information stored in the storage unit, the controller determines a failure of the component based on the first snapshot data and the information stored in the storage unit when a failure of the component cannot be determined based on the second snapshot data.

2. The failure diagnosis system of the work machine according to claim 1, wherein the controller generates an instruction signal for operating the work machine, the controller acquires time series data of the physical quantity detected within the first period from a time point at which the physical quantity is initially judged to have deviated from the normal range as the first snapshot data after generating the instruction signal.

3. The failure diagnosis system of the work machine according to claim 1 or 2, wherein the controller saves the first snapshot data in the storage unit.

4. The failure diagnosis system of the work machine according to claim 1 or 2, wherein the information stored in the storage unit includes information associating a failure of the component with a countermeasure against the failure, the controller outputs a countermeasure against the determined failure based on the information stored in the storage unit.

5. The failure diagnosis system of the work machine according to claim 4, wherein in a case where there are a plurality of countermeasures against a failure, the controller outputs the countermeasures with priority.

6. A failure diagnosis method of a work machine that comprises a component and a detection unit that detects a prescribed physical quantity in order to monitor an operation state of the component, wherein information associating a deviation of the physical quantity detected by the detection unit from a normal range with a failure of the component as a cause of the deviation is stored in a storage unit, the failure diagnosis method of the work machine comprises the steps of: acquiring time series data of the physical quantity detected within a first period as first snapshot data; acquiring time series data of the physical quantity detected within a second period later than the first period as second snapshot data; judging whether a failure of the component can be determined based on the second snapshot data and the information stored in the storage unit; and ​ When it is not possible to determine the failure of the component based on the second snapshot data, the failure of the component is determined based on the first snapshot data and information stored in the storage section.

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