Oil abnormality detection system, oil abnormality detection method, and oil abnormality detection program

Abstract

To suppress the occurrence of problems in an actuator when there is an abnormality in oil.SOLUTION: An oil sensor 50 detects at least one of viscosity, kinematic viscosity, temperature, and dielectric constant of oil. An abnormality determination unit 72 can determine whether or not there is abnormality in the oil based on the detection value of the oil sensor 50. An operation control unit 76 controls the operation of an actuator A. When the abnormality determination unit 72 determines that there is no abnormality in the oil, the operation control unit 76 controls the actuator A by predetermined normal control. When the abnormality determination unit 72 determines that there is an abnormality in the oil, the operation control unit 76 controls the actuator A by the oil abnormality time control different from the normal control.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an oil abnormality detection system, an oil abnormality detection method, and an oil abnormality detection program for detecting abnormalities in oil.

Background Art

[0002] For example, Patent Document 1 describes a technique for determining an abnormality (in this document, a deterioration state) of oil used by an actuator (in this document, an engine) in consideration of the temperature of the oil and the like.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the technique described in this document, even when there is an abnormality in the oil, the actuator is controlled in the same manner as when there is no abnormality in the oil. Therefore, there is a risk of problems occurring in the actuator.

[0005] Therefore, an object of the present invention is to provide an oil abnormality detection system, an oil abnormality detection method, and an oil abnormality detection program that can suppress problems from occurring in an actuator when there is an abnormality in the oil.

Means for Solving the Problems

[0006] The oil abnormality detection system comprises an actuator, an oil sensor, an abnormality determination unit, and an operation control unit. The actuator operates a work machine and utilizes oil. The oil sensor detects at least one of the viscosity, kinematic viscosity, temperature, and dielectric constant of the oil. The abnormality determination unit can determine whether or not there is an abnormality in the oil based on the value detected by the oil sensor. The operation control unit controls the operation of the actuator. If the abnormality determination unit determines that there is no abnormality in the oil, the operation control unit controls the actuator by predetermined normal control. If the abnormality determination unit determines that there is an abnormality in the oil, the operation control unit controls the actuator by oil abnormality control, which is different from the normal control.

[0007] The oil abnormality detection method comprises a detection step, an abnormality determination step, a normal control step, and an abnormality control step. The detection step detects at least one of the viscosity, kinematic viscosity, temperature, and dielectric constant of the oil used by the actuator that operates the work machine. The abnormality determination step determines whether or not there is an abnormality in the oil based on the value detected in the detection step. The normal control step controls the actuator by predetermined normal control if the abnormality determination step determines that there is no abnormality in the oil. The abnormality control step controls the actuator by oil abnormality control different from the normal control if the abnormality determination step determines that there is an abnormality in the oil.

[0008] The oil abnormality detection program causes a computer to perform a detection step, an abnormality determination step, a normal control step, and an abnormality control step. The detection step detects at least one of the viscosity, kinematic viscosity, temperature, and dielectric constant of the oil used by the actuator that operates the work machine. The abnormality determination step determines whether or not there is an abnormality in the oil based on the value detected in the detection step. The normal control step controls the actuator by predetermined normal control if the abnormality determination step determines that there is no abnormality in the oil. The abnormality control step controls the actuator by oil abnormality control different from the normal control if the abnormality determination step determines that there is an abnormality in the oil. [Effects of the Invention]

[0009] The oil abnormality detection system, oil abnormality detection method, and oil abnormality detection program described above can suppress problems occurring in the actuator when there is an oil abnormality. [Brief explanation of the drawing]

[0010] [Figure 1] This is a block diagram showing the oil passages and other components of the oil abnormality detection system 1. [Figure 2] Figure 1 is a block diagram showing the controller 70 and other components of the oil abnormality detection system 1. [Figure 3] Figure 1 is a flowchart showing the operation of the oil abnormality detection system 1. [Figure 4] Figure 3 shows an example of control modification by the operation control unit 76. [Modes for carrying out the invention]

[0011] The oil abnormality detection system 1 will be described with reference to Figures 1 to 4.

[0012] The oil abnormality detection system 1 is a system for detecting abnormalities in oil. The oil targeted for abnormality detection by the oil abnormality detection system 1 shown in Figure 1 (hereinafter simply referred to as "oil") is used in the actuator A of the work machine 10. For example, the oil may be lubricating oil, fuel, or hydraulic oil. More specifically, the oil may be the fuel for the engine 21 (actuator A) (e.g., diesel or gasoline). The fuel for the engine 21 can also be the lubricating oil inside the engine 21. The oil may be engine oil that lubricates the inside of the engine 21. The oil may also be hydraulic oil supplied to the hydraulic actuator 37 (actuator A) to operate and lubricate the hydraulic actuator 37. The oil abnormality detection system 1 comprises the work machine 10, a controller 70, a notification unit 81 shown in Figure 2, a server 83, and a security processing unit 85.

[0013] As shown in Figure 1, the work machine 10 is a machine that performs work, for example, a construction machine that performs construction work, and may be an excavator or a crane. The following description will focus on the case where the work machine 10 is an excavator. The work machine 10 may be operated by a worker (operator) in the driver's cab 13a (described later), may be remotely operated, or may be automatically operated. The work machine 10 comprises a lower traveling body 11, an upper rotating body 13, an attachment 15, and an operating unit 17. The work machine 10 also comprises an engine 21, fuel-related equipment 23, engine oil-related equipment 25, a hydraulic circuit 30, an oil sensor 50, a flow velocity acquisition unit 61 (see Figure 2), and an oil-related information acquisition unit 63 (see Figure 2).

[0014] The lower traveling body 11 drives the work machine 10. The lower traveling body 11 may be equipped with crawlers or wheels.

[0015] The upper slewing body 13 is rotatably mounted on the lower traveling body 11. The upper slewing body 13 is equipped with a cab 13a. The cab 13a is the part from which an operator can operate the work machine 10.

[0016] Attachment 15 is the part that performs the work and comprises, for example, a boom 15a, an arm 15b, and a tip attachment 15c. The boom 15a is mounted on the upper slewing body 13 so as to be able to raise and lower (rotate vertically). The arm 15b is mounted rotatably to the boom 15a. The tip attachment 15c is provided at the tip of attachment 15 and is rotatably mounted to the arm 15b. The tip attachment 15c may be, for example, a bucket used for scooping or excavating workpieces, a device for gripping workpieces (grapple, nibbler, etc.), or a device for crushing workpieces (breaker, etc.).

[0017] The control unit 17 is operated by an operator to control actuator A. For example, the control unit 17 may be for operating a hydraulic actuator 37, or for operating the engine 21 (starting, stopping, speed control, etc.). The control unit 17 may be located in the operator's cab 13a, in a remote control unit for remotely controlling the work machine 10, or in a terminal device (such as a tablet) for remotely controlling the work machine 10. The control unit 17 does not have to be a component of the work machine 10. The control unit 17 may be, for example, a lever, pedal, switch, button, or touch panel. Multiple control units 17 may be provided. In Figure 1, only one control unit 17 for operating one hydraulic actuator 37 is shown.

[0018] Engine 21 (actuator A) operates the work machine 10. Engine 21 is the power source for the work machine 10. Engine 21 may, for example, drive the hydraulic oil pump 32 or a generator. Engine 21 is mounted on the upper slewing body 13. The same applies to the fuel-related equipment 23, engine oil-related equipment 25, hydraulic circuit 30 (excluding part of the hydraulic actuator 37), oil sensor 50, flow velocity acquisition unit 61 (see Figure 2), and oil-related information acquisition unit 63 (see Figure 2), which are mounted on the upper slewing body 13. Engine 21 is an internal combustion engine, for example, a diesel engine. Engine 21 uses oil (fuel and engine oil). More specifically, engine 21 uses fuel to drive itself. Engine 21 also uses engine oil for lubrication inside itself.

[0019] Fuel-related equipment 23 is equipment related to the fuel of the engine 21. Fuel-related equipment 23 comprises a fuel tank 23a, a fuel separator 23c (separator), a fuel pump 23g (pump), a common rail 23i, and a fuel passage 23k (oil passage). The fuel tank 23a is a tank in which fuel is stored. The fuel separator 23c separates mixtures (mixtures into the fuel) mixed with the fuel from the fuel. The fuel separator 23c comprises a fuel water separator 23c1 and a fuel filter 23c2. The fuel water separator 23c1 separates water mixed with the fuel from the fuel. The fuel filter 23c2 separates (filters) mixtures (particles, etc.) from the fuel. The fuel pump 23g draws in fuel and supplies pressurized fuel to the engine 21. The fuel pump 23g is, for example, an electric pump. The common rail 23i is a pipe that distributes fuel into the engine 21. The fuel passage 23k is a passage (pipe) through which fuel flows. The fuel passage 23k is connected to each component so that fuel flows in the following order: fuel tank 23a, fuel water separator 23c1, fuel filter 23c2, fuel pump 23g, common rail 23i, and inside the engine 21. The fuel flows, for example, as follows: While the engine 21 is running (after starting), the fuel pump 23g is driven. Then, fuel is drawn up from the fuel tank 23a, passes through the fuel water separator 23c1 and fuel filter 23c2 (filtered), and is pressurized by the fuel pump 23g. The pressurized fuel is stored in the common rail 23i and, depending on the operating conditions of the engine 21, is injected from the common rail 23i into the cylinders of the engine 21 by injectors (not shown).

[0020] The engine oil-related equipment 25 is equipment related to the engine oil of the engine 21. The engine oil-related equipment 25 includes an oil pan 25a, an engine oil separator 25c (separator), an engine oil pump 25g (pump), and an engine oil passage 25k (oil passage). The oil pan 25a is a tank in which engine oil is stored. The engine oil separator 25c separates a mixture (mixture into engine oil) mixed in the engine oil from the engine oil. The engine oil separator 25c includes an engine oil water separator 25c1 and an engine oil filter 25c2. The engine oil water separator 25c1 separates water mixed in the engine oil from the engine oil. The engine oil filter 25c2 separates (filters) a mixture (such as particles of metal powder) from the engine oil. The engine oil pump 25g sucks in the engine oil and supplies it to various locations (such as inside the cylinders) inside the engine 21. The engine oil passage 25k is a passage (pipe) through which the engine oil passes. The engine oil passage 25k is connected to each device so that the engine oil flows in the order of the oil pan 25a, the engine oil water separator 25c1, the engine oil filter 25c2, the engine oil pump 25g, and the inside of the engine 21. The engine oil flows as follows, for example. The engine 21 drives the engine oil pump 25g. Then, the engine oil is sucked up from the oil pan 25a and passes through (is filtered by) the engine oil water separator 25c1 and the engine oil filter 25c2. And the engine oil is supplied inside the engine 21, cools each part of the engine 21, and then returns to the oil pan 25a.

[0021] The hydraulic circuit 30 includes a circuit for operating the hydraulic actuator 37 and the hydraulic actuator 37. The hydraulic circuit 30 includes a hydraulic oil tank 31, a hydraulic oil pump 32, a valve 35, a hydraulic actuator 37, a hydraulic oil filter 39, and a hydraulic oil passage 41 (oil passage).

[0022] The hydraulic oil tank 31 is a tank for storing hydraulic oil. The hydraulic oil pump 32 supplies hydraulic oil to the hydraulic actuator 37. The hydraulic oil pump 32 is driven (rotationally driven) by the engine 21. The hydraulic oil pump 32 sucks in hydraulic oil from the hydraulic oil tank 31 and supplies hydraulic oil (pressure oil) to the hydraulic actuator 37.

[0023] The valve 35 is a valve that controls the flow of hydraulic oil. For example, the valve 35 may be a valve (control valve) that controls the direction and flow rate of the hydraulic oil supplied from the hydraulic oil pump 32 to the hydraulic actuator 37. The valve 35 may also be a valve other than the above control valve for controlling the operation of the hydraulic actuator 37.

[0024] The hydraulic actuator 37 (actuator A) operates the work machine 10. The hydraulic actuator 37 utilizes hydraulic oil. More specifically, the hydraulic actuator 37 operates when hydraulic oil is supplied. The inside of the hydraulic actuator 37 is lubricated by hydraulic oil. For example, the hydraulic actuator 37 includes a travel motor (not shown) that travels the lower traveling body 11. The hydraulic actuator 37 includes a swing motor (not shown) that swings the upper swing body 13 with respect to the lower traveling body 11. The travel motor and the swing motor are hydraulic motors. The hydraulic actuator 37 includes a boom cylinder (not shown) that raises and lowers the boom 15a with respect to the upper swing body 13. The hydraulic actuator 37 includes an arm cylinder (not shown) that rotates the arm 15b with respect to the boom 15a. The hydraulic actuator 37 includes a tip attachment cylinder (not shown) that rotates the tip attachment 15c with respect to the arm 15b. The boom cylinder, the arm cylinder, and the tip attachment cylinder are hydraulic cylinders. When the tip attachment 15c itself is drivable, for example, like a device for clamping an object, the hydraulic actuator 37 may include a hydraulic cylinder or a hydraulic motor for driving the tip attachment 15c. In FIG. 1, two of each of the hydraulic oil pump 32, the valve 35, and the hydraulic actuator 37 are shown, but the number of these can be set variously.

[0025] The hydraulic oil filter 39 separates the mixture mixed in with the hydraulic oil (mixture to the hydraulic oil) from the hydraulic oil. For example, the hydraulic oil filter 39 may be provided in the drain passage 41g (described later) or in the return passage 41e (described later).

[0026] The hydraulic fluid passage 41 (oil passage) is a passage (pipe) through which hydraulic fluid flows. The hydraulic fluid passage 41 comprises a suction passage 41a, a supply passage 41c, a return passage 41e, and a drain passage 41g. The suction passage 41a is the passage through which hydraulic fluid is drawn from the hydraulic fluid tank 31 to the hydraulic fluid pump 32. The supply passage 41c is the passage through which hydraulic fluid is supplied from the hydraulic fluid pump 32 to the hydraulic actuator 37. The return passage 41e is the passage through which hydraulic fluid discharged from the hydraulic fluid pump 32 and returning to the hydraulic fluid tank 31 flows. More specifically, the return passage 41e may also contain hydraulic fluid supplied from the hydraulic fluid pump 32 to the hydraulic actuator 37, discharged from the hydraulic actuator 37, and returning to the hydraulic fluid tank 31. Alternatively, the return passage 41e may also contain hydraulic fluid discharged from the hydraulic fluid pump 32 that returns to the hydraulic fluid tank 31 without being supplied to the hydraulic actuator 37. The drain passage 41g is a passage for returning the drained hydraulic fluid to the hydraulic fluid tank 31. The drain passage 41g is connected to each hydraulic device (hydraulic fluid pump 32 in Figure 1) and the hydraulic fluid tank 31. The hydraulic fluid flows, for example, as follows: The engine 21 drives the hydraulic fluid pump 32. Then, hydraulic fluid is drawn up from the hydraulic fluid tank 31 to the hydraulic fluid pump 32. The hydraulic fluid is discharged from the hydraulic fluid pump 32 as pressurized oil, passes through the valve 35, and is supplied to the hydraulic actuator 37. The hydraulic fluid is then discharged from the hydraulic actuator 37, passes through the hydraulic fluid filter 39 (is filtered), and is returned to the hydraulic fluid tank 31. In addition, hydraulic fluid is returned from each hydraulic device (for example, the hydraulic fluid pump 32) through the drain passage 41g, through the hydraulic fluid filter 39, and back to the hydraulic fluid tank 31.

[0027] The oil sensor 50 is a sensor (oil property sensor, oil characteristic sensor) that detects the state of the oil. The oil sensor 50 detects information to determine whether the oil is abnormal or not. The oil sensor 50 detects at least one of the following properties of the oil: viscosity (viscosity coefficient), kinematic viscosity (kinematic viscosity coefficient, value obtained by dividing viscosity by density), temperature, and dielectric constant. The oil sensor 50 may also detect the density of the oil. Note that the density of the oil may be measured by a sensor other than the oil sensor 50. Furthermore, the kinematic viscosity of the oil may be calculated based on the viscosity detected by the oil sensor 50 and the density of the oil. The viscosity of the oil may be calculated based on the kinematic viscosity detected by the oil sensor 50 and the density of the oil.

[0028] The detection accuracy of the oil sensor 50 depends on the oil flow velocity. Therefore, it is preferable that the oil sensor 50 detects the state of the oil at a position where the oil flow velocity can be within a predetermined flow velocity range. The "predetermined flow velocity range" is a range of oil flow velocity that allows for accurate detection of the oil state (ensuring a predetermined accuracy). The "predetermined flow velocity range" only needs to have at least one of an upper or lower limit. At the "position where the oil flow velocity can be within the predetermined flow velocity range," there may be times when the oil flow velocity is not within the predetermined flow velocity range. Specific examples of the position of the oil sensor 50 will be described later.

[0029] The oil sensor 50 may be provided as a single unit or as a group. When multiple oil sensors 50 are provided, the types of oil conditions detected by each oil sensor 50 (e.g., temperature, viscosity, kinematic viscosity, dielectric constant, etc.) may differ from one another. If the types of oil conditions detected by multiple oil sensors 50 are the same, the controller 70 (see Figure 2) may perform the following processing. For example, the controller 70 may use the weighted average of the detected values ​​(conditions) of each oil sensor 50 as the oil condition. In this case, the weights of the condition of each oil sensor 50 may be set according to, for example, the arrangement of each oil sensor 50. Alternatively, it is desirable for the controller 70 to use the average of the detected values ​​obtained by excluding values ​​that are likely to be abnormal, specifically the upper values ​​(e.g., maximum value) and lower values ​​(e.g., minimum value), from the detected values ​​of each oil sensor 50 as the oil condition.

[0030] Specifically, the oil sensor 50 may include, for example, a tuning fork. The oil sensor 50 may detect the state of the oil based on the electrical characteristics of the tuning fork (e.g., capacitance). More specifically, the tuning fork is immersed in the oil and vibrates when a voltage of a predetermined frequency (oscillation frequency) is applied. When a voltage is applied to the tuning fork, a current is generated between the electrodes of the tuning fork. The electrical characteristics of the tuning fork then change depending on the state (properties) of the oil. If the oil sensor 50 uses a tuning fork, the oil sensor 50 itself (the tuning fork) vibrates, so if the oil flow velocity is too fast (exceeding a certain flow velocity upper limit), the detection accuracy of the oil sensor 50 cannot be ensured. Therefore, it is preferable that the oil sensor 50 detects the state of the oil when the oil flow velocity is less than the flow velocity upper limit. In this case, the detection accuracy of the oil sensor 50 can be ensured. For example, it is more preferable that the oil sensor 50 detects the state of the oil when the oil flow velocity is as low as possible. Note that the oil sensor 50 does not necessarily have to include a tuning fork.

[0031] This oil sensor 50 includes a fuel sensor 51, an engine oil sensor 53, and a hydraulic fluid sensor 55.

[0032] The fuel sensor 51 detects the state of the fuel. The fuel sensor 51 is installed in the fuel passage 23k. The following describes a case in which the detection accuracy of the fuel sensor 51 can be ensured when the oil flow velocity is less than a certain upper limit of flow velocity (the same applies to the engine oil sensor 53 and the hydraulic fluid sensor 55). It is preferable that the fuel sensor 51 be positioned at a location where the fuel flow velocity can be less than a certain upper limit of flow velocity. It is preferable that the fuel sensor 51 be positioned at a location in the fuel passage 23k where the flow velocity is relatively low, and more preferably at a location where the flow velocity is as low as possible. For example, the fuel sensor 51 may be positioned to detect the fuel in the fuel passage 23k between the fuel water separator 23c1 (separator) and the fuel pump 23g. Alternatively, for example, the fuel sensor 51 may be positioned to detect the fuel in the fuel passage 23k between the fuel filter 23c2 (separator) and the fuel pump 23g.

[0033] The engine oil sensor 53 detects the condition of the engine oil. The engine oil sensor 53 is provided in the engine oil passage 25k. Preferably, the engine oil sensor 53 is positioned at a location where the flow velocity of the engine oil can be less than a certain upper limit of flow velocity. Preferably, the engine oil sensor 53 is positioned in the engine oil passage 25k at a location where the flow velocity is relatively low, and more preferably at a location where the flow velocity is as low as possible. For example, the engine oil sensor 53 may be positioned to detect the engine oil in the engine oil passage 25k between the engine oil water separator 25c1 (separation device) and the engine oil pump 25g. Alternatively, for example, the engine oil sensor 53 may be positioned to detect the engine oil in the engine oil passage 25k between the engine oil filter 25c2 (separation device) and the engine oil pump 25g.

[0034] The hydraulic fluid sensor 55 detects the state of the hydraulic fluid. The hydraulic fluid sensor 55 is installed in the hydraulic fluid passage 41. It is preferable that the hydraulic fluid sensor 55 be installed at a position where the flow velocity of the hydraulic fluid can be less than a certain upper limit of flow velocity. It is preferable that the hydraulic fluid sensor 55 be installed at a position in the hydraulic fluid passage 41 where the flow velocity is relatively low, and more preferably at a position where the flow velocity is as low as possible. Specifically, for example, the hydraulic fluid sensor 55 is installed to detect the hydraulic fluid in the hydraulic fluid passage 41 between the hydraulic fluid filter 39 and the hydraulic fluid tank 31. For example, the hydraulic fluid sensor 55 is installed to detect the hydraulic fluid in the drain passage 41g between the hydraulic fluid filter 39 and the hydraulic fluid tank 31. For example, the hydraulic fluid sensor 55 is installed near the downstream sensor of a sensor (not shown) that detects the differential pressure before and after the hydraulic fluid filter 39 (the differential pressure between the upstream and downstream sides of the hydraulic fluid filter 39). The hydraulic fluid sensor 55 may also be installed in a location other than the above-described example within the hydraulic fluid passage 41 (such as the suction passage 41a or the return passage 41e).

[0035] The flow velocity acquisition unit 61 (see Figure 2) acquires the flow velocity of the oil. The flow velocity acquisition unit 61 may acquire (detect) the oil flow velocity directly or indirectly. The flow velocity acquisition unit 61 may detect the oil flow velocity by detecting the oil flow rate. The flow velocity acquisition unit 61 may acquire the flow velocity of the oil discharged by the pump by acquiring the pump status. The "pump status" detected by the flow velocity acquisition unit 61 may be, for example, the rotational speed of the fuel pump 23g or the rotational speed of the engine oil pump 25g. The "pump status" detected by the flow velocity acquisition unit 61 may be, for example, the capacity and rotational speed of the hydraulic oil pump 32. The "pump status" detected by the flow velocity acquisition unit 61 may be, for example, the rotational speed of the engine 21 that drives the hydraulic oil pump 32. The flow velocity acquisition unit 61 may detect the flow velocity by acquiring commands from the controller 70 to the pump. In this case, the flow velocity acquisition unit 61 may be the controller 70.

[0036] The oil-related information acquisition unit 63 (see Figure 2) is provided separately from the oil sensor 50. The oil-related information acquisition unit 63 does not directly detect the state of the oil, but acquires information that affects the state of the oil. For example, the oil-related information acquisition unit 63 detects information that affects the oil temperature (oil temperature-related information acquisition unit). For example, the oil-related information acquisition unit 63 may acquire (detect) the temperature of the engine 21, specifically, for example, the temperature of the coolant of the engine 21 (engine water temperature). Alternatively, for example, the oil-related information acquisition unit 63 may acquire (detect) the temperature of the air surrounding the work machine 10 (ambient temperature).

[0037] The controller 70 is a computer that performs signal input / output, calculations (processing), and information storage. For example, the functions of the controller 70 are realized by the execution of a program stored in the controller 70's memory unit (not shown) by the calculation unit (not shown). For example, the controller 70 receives input such as the detection result from the oil sensor 50, the operation content of the operation unit 17, information acquired by the flow velocity acquisition unit 61 (see Figure 2), and information acquired by the oil-related information acquisition unit 63 (see Figure 2). The controller 70 may be installed in only one location or in multiple locations. The controller 70 may be mounted on the work machine 10 or placed outside the work machine 10 (for example, on the server 83 (see Figure 2)). As shown in Figure 2, the controller 70 includes an indicator calculation unit 71, an abnormality determination unit 72, an abnormality operation time count unit 73, a flow velocity determination unit 74, a notification generation unit 75, an operation control unit 76, and a communication unit 77.

[0038] The index calculation unit 71 (index calculation device) calculates an index used to determine whether or not there is an oil abnormality (oil abnormality determination). The index calculation unit 71 only needs to be provided when an index is necessary for oil abnormality determination. Specific examples of the index will be described later.

[0039] The abnormality determination unit 72 (abnormality determination device) determines whether or not there is an abnormality in the oil based on the detected value of the oil sensor 50. The determination by the abnormality determination unit 72 regarding the presence or absence of an abnormality in the oil based on the detected value of the oil sensor 50 is called "oil abnormality determination". There may be times when the abnormality determination unit 72 does not perform oil abnormality determination (details will be described later). The abnormality determination unit 72 may perform oil abnormality determination based on an index calculated by the index calculation unit 71. The abnormality determination unit 72 may perform oil abnormality determination directly from the detected value of the oil sensor 50 (without calculating an index). Details of oil abnormality determination will be described later.

[0040] The abnormal operation time counting unit 73 counts (accumulates, sums) the time the operation unit 17 is operated when the abnormality detection unit 72 has determined that there is an abnormality in the oil (details will be described later).

[0041] The flow velocity determination unit 74 makes a determination regarding the oil flow velocity acquired by the flow velocity acquisition unit 61. The flow velocity determination unit 74 determines whether the oil flow velocity is within a predetermined flow velocity range (a range in which the state of the oil can be detected with high accuracy) (details will be described later).

[0042] The notification generation unit 75 (for example, an alert generation device) generates a notification. The notification generated by the notification generation unit 75 is the notification output by the notification unit 81 when the abnormality detection unit 72 determines that there is an abnormality in the oil (details will be described later).

[0043] The operation control unit 76 controls (e.g., limits) the operation of the work machine 10. The operation control unit 76 controls the operation of actuator A. The operation control unit 76 comprises an engine control unit 76a and a hydraulic circuit control unit 76b. The engine control unit 76a controls the operation of the engine 21. The engine control unit 76a controls the starting and stopping of the engine 21. The engine control unit 76a controls the rotational speed of the engine 21. The hydraulic circuit control unit 76b controls the operation of the hydraulic actuator 37 by controlling the hydraulic circuit 30. For example, the hydraulic circuit control unit 76b may control the operation of the hydraulic actuator 37 by controlling the hydraulic oil pump 32 (see Figure 1) (e.g., the capacity of the hydraulic oil pump 32). For example, the hydraulic circuit control unit 76b may control the operation of the hydraulic actuator 37 by controlling the opening degree of the valve 35 (see Figure 1). For example, the hydraulic circuit control unit 76b may control (directly control) the state of the hydraulic actuator 37. Specifically, for example, if the hydraulic actuator 37 is a hydraulic motor, the hydraulic circuit control unit 76b may control the capacity of the hydraulic motor.

[0044] The communication unit 77 handles the communication of information exchanged in the oil abnormality detection system 1. The communication performed by the communication unit 77 may be wired or wireless. Specifically, for example, if the controller 70 is installed in the work machine 10 (see Figure 1), and the notification unit 81 and server 83 are installed outside the work machine 10, the communication unit 77 will communicate between the controller 70, the notification unit 81, and the server 83. In this case, the notification unit 81 and the server 83 are also provided with communication units 77 (not shown).

[0045] The notification unit 81 issues a notification when the abnormality detection unit 72 determines that there is an abnormality in the oil. The notification unit 81 notifies the operator (person). The notification unit 81 may be mounted on the work machine 10 shown in Figure 1, or it may be located inside the operator's cab 13a, for example. The notification unit 81 shown in Figure 2 may be located outside the work machine 10 (see Figure 1). In this case, the notification unit 81 may be provided on the server 83, or it may be provided on a device different from the server 83. When the notification unit 81 is provided outside the work machine 10 and on a device different from the server 83, the notification unit 81 may be, for example, a communication device (terminal device), and specifically it may be, for example, a personal computer, a tablet, or a smartphone. The content of the notification by the notification unit 81 will be described later.

[0046] Server 83 is a computer that processes information. Server 83 is located outside the work machine 10 (see Figure 1). Server 83 may be part of controller 70, or it may not be part of controller 70.

[0047] The security processing unit 85 performs information security processing on the information exchanged in the oil abnormality detection system 1. The security processing unit 85 may be located in the controller 70 or outside the controller 70. Specific examples of processing performed by the security processing unit 85 will be described later.

[0048] (Operation) The oil abnormality detection system 1 is configured to operate as follows. Each step (S11-S15, S30) will be explained below with reference to Figure 3.

[0049] (Timing of oil abnormality detection) The timing of oil abnormality detection is as follows, for example:

[0050] [Example of timing 1 (when step S11 is present)] The controller 70 shown in Figure 2 may change whether or not the abnormality determination unit 72 performs an oil abnormality determination depending on the oil flow velocity detected by the flow velocity acquisition unit 61 (see steps S11 to S14). A specific example of when the abnormality determination unit 72 performs an oil abnormality determination depending on the oil flow velocity detected by the flow velocity acquisition unit 61 is as follows.

[0051] In step S11, the flow velocity determination unit 74 determines whether the oil flow velocity acquired by the flow velocity acquisition unit 61 is within a predetermined flow velocity range. The "predetermined flow velocity range" is set in the controller 70 (more specifically, the flow velocity determination unit 74) before this determination. The same applies to other thresholds, ranges, etc., which are set in the controller 70 before any processing (such as determination).

[0052] If the oil flow velocity acquired by the flow velocity acquisition unit 61 is not within a predetermined flow velocity range (the result is NO in step S11), the abnormality determination unit 72 does not perform an oil abnormality determination (step S14 is not performed). For example, if the result is NO in step S11, the oil sensor 50 does not need to detect the state of the oil (the flow does not need to proceed to step S12). Also, for example, if the result is NO in step S11, the oil sensor 50 detects the state of the oil, and the abnormality determination unit 72 does not need to perform an oil abnormality determination based on the oil state detected at this time (not shown). In other words, the abnormality determination unit 72 does not need to perform an oil abnormality determination based on the detected value of the oil sensor 50 when the oil flow velocity acquired by the flow velocity acquisition unit 61 is not within a predetermined flow velocity range (the result is NO in step S11).

[0053] When the oil flow velocity acquired by the flow velocity acquisition unit 61 is within a predetermined flow velocity range (if YES is obtained in step S11), the controller 70 processes as follows: If YES is obtained in step S11, the oil sensor 50 detects the state of the oil (step S12) (detection step). Then, the abnormality determination unit 72 performs an oil abnormality determination (step S14) based on the detected value detected by the oil sensor 50 (step S12) while the oil flow velocity acquired by the flow velocity acquisition unit 61 is within a predetermined flow velocity range (if YES is obtained in step S11). In this case, the detected value of the oil that the abnormality determination unit 72 uses to determine whether or not there is an oil abnormality is the detected value of the oil detected by the oil sensor 50 while the oil flow velocity detected by the flow velocity acquisition unit 61 is within a predetermined flow velocity range.

[0054] [Timing example 2 (when step S11 is not present)] Furthermore, the controller 70 does not need to change whether or not the abnormality determination unit 72 performs an oil abnormality determination according to the oil flow velocity acquired by the flow velocity acquisition unit 61 (step S11 does not need to be performed). For example, in a situation (a predetermined situation) in which it is expected that the oil flow velocity will be such that the detection accuracy of the oil sensor 50 can be ensured, the abnormality determination unit 72 may perform an oil abnormality determination based on the state of the oil detected by the oil sensor 50. The above "predetermined situation" is, for example, immediately after starting the work machine 10 (see Figure 1) (for example, after turning on the key), and more specifically, for example, N seconds after starting the work machine 10. The above N can be set in various ways. For example, the above N is a time shorter than the time from when the work machine 10 is started until it is expected that work by the work machine 10 will begin. For example, the above N may be the time required to warm up the work machine 10.

[0055] In step S13, the index calculation unit 71 calculates an index for determining an oil abnormality based on the value detected by the oil sensor 50.

[0056] In step S14, the abnormality determination unit 72 makes an oil abnormality determination based on the value detected by the oil sensor 50 (determines whether or not there is an oil abnormality) (abnormality determination step). If the abnormality determination unit 72 determines that there is an oil abnormality (YES in step S14), the flow proceeds to step S15. If the abnormality determination unit 72 determines that there is no oil abnormality, the flow returns to step S11. If the abnormality determination unit 72 determines that there is no oil abnormality, the operation control unit 76 controls the actuator A by predetermined normal control (normal control step). The above "normal control" is, for example, control according to the operation of the operation unit 17. Normal control is the control of actuator A by the operation control unit 76 when no control changes described later have been made.

[0057] The details of the oil abnormality determination performed by the abnormality determination unit 72 are as follows. The "abnormality" of the oil detected by the abnormality determination unit 72 is an abnormality (for example, oil deterioration) that may cause problems (affect) in the equipment that uses the oil (engine 21, hydraulic circuit 30, etc.). For example, an "abnormality" of the oil is a condition in which friction in the equipment that uses the oil becomes greater than the permissible range, making seizure more likely.

[0058] The abnormality detection unit 72 can perform oil abnormality detection using various methods (from various perspectives). The abnormality detection unit 72 may perform oil abnormality detection using one of the following multiple methods, or it may perform oil abnormality detection using a combination of multiple methods. When the abnormality detection unit 72 performs oil abnormality detection using multiple methods, for example, it may calculate the degree of abnormality for each method and perform oil abnormality detection based on the sum of the degrees of abnormality. In this case, weighting of the degree of abnormality may be performed for each method.

[0059] The abnormality determination unit 72 may determine an oil abnormality based on the detected value of the oil sensor 50 itself. The abnormality determination unit 72 may determine an oil abnormality based on an index calculated by the index calculation unit 71 from the detected value of the oil sensor 50. Specifically, for example, the abnormality determination unit 72 may determine an oil abnormality based on an abnormality (too high, too low, etc.) in at least one of the following: oil temperature, oil viscosity, oil kinematic viscosity, and oil dielectric constant. The abnormality determination unit 72 may determine an oil abnormality based on at least one of the following: the degree of chemical change such as oxidation of the oil, the degree of mixing of a mixture into the oil, and the degree of reduction of additives in the oil. The abnormality determination unit 72 may determine an oil abnormality based on the detected value of the oil sensor 50 and information other than the detected value of the oil sensor 50 (for example, information acquired by the oil-related information acquisition unit 63).

[0060] (Specific examples of oil abnormality detection) [Example of Judgment A] The abnormality determination unit 72 may determine an oil abnormality based solely on the oil temperature. Specifically, for example, the normal oil temperature during operation of the work machine 10 may be measured in advance, and the normal oil range (temperature range) may be stored in the controller 70. Then, if the oil temperature detected by the oil sensor 50 is not included in the normal oil temperature range, the abnormality determination unit 72 may determine that the oil is abnormal. Similarly, the abnormality determination unit 72 may determine an oil abnormality based on whether the dielectric constant of the oil detected by the oil sensor 50 is included in the normal range (dielectric constant range). The abnormality determination unit 72 may determine an oil abnormality based on whether the viscosity of the oil detected by the oil sensor 50 is included in the normal range (viscosity range). The abnormality determination unit 72 may determine an oil abnormality based on whether the kinematic viscosity of the oil detected by the oil sensor 50 is included in the normal range (kinematic viscosity range). If information on the oil density is available, the oil viscosity and kinematic viscosity can be converted to each other. Therefore, the abnormality determination unit 72 may perform an oil abnormality determination based on the oil's kinematic viscosity calculated based on the oil's density and the oil's viscosity detected by the oil sensor 50. The abnormality determination unit 72 may perform an oil abnormality determination based on the oil's viscosity calculated based on the oil's density and the oil's kinematic viscosity detected by the oil sensor 50. The following explanation regarding kinematic viscosity may be read as an explanation regarding viscosity.

[0061] [Example of Judgment B] The abnormality determination unit 72 may perform an oil abnormality determination based on the kinematic viscosity and temperature of the oil. Specifically, for example, the normal relationship between the kinematic viscosity and temperature of the oil during the operation of the work machine 10 (kinematic viscosity-temperature characteristics) is measured in advance, and the normal kinematic viscosity-temperature characteristics are stored in the controller 70. Then, if the relationship between the kinematic viscosity and temperature of the oil detected by the oil sensor 50 deviates from the normal kinematic viscosity-temperature characteristics (for example, if the degree of deviation exceeds a predetermined value), the abnormality determination unit 72 may determine that the oil is abnormal.

[0062] Comparing oil abnormality detection based solely on oil temperature with detection based on both oil temperature and kinematic viscosity, the latter method utilizes more parameters for detection. Therefore, it allows for more accurate detection of oil abnormalities.

[0063] [Example of Judgment C] The abnormality determination unit 72 may perform an oil abnormality determination based on the degree of mixing of the mixture into the oil. Examples of oil abnormality determination when the mixture in the oil is liquid include [Example of Judgment C1] to [Example of Judgment C4] below. An example of judgment when the mixture in the oil is solid is [Example of Judgment C5] below.

[0064] [Example of judgment C1] (Mixture is liquid, judgment based on kinematic viscosity) The oil sensor 50 detects the kinematic viscosity of the oil within a predetermined temperature range (e.g., 30°C to 60°C). The controller 70 takes an Arrhenius plot from the temperature and kinematic viscosity and fits the Arrhenius plot to the Andrade model (Andrade equation). At this time, the Andrade model is applied assuming that the mixture is completely (uniformly) dispersed in the oil, which is the solvent (the same applies to [Example C5 of the judgment] below). The controller 70 calculates the free energy value from the slope of the Andrade model graph. This free energy value depends on the degree of mixing. Therefore, the abnormality determination unit 72 may use the free energy value calculated in this way as an indicator of the degree of mixing (an indicator for abnormality determination) to determine if the oil is abnormal.

[0065] [Example of judgment C2] (Mixture is liquid, judgment based on kinematic viscosity) For oils in various states (including normal and abnormal states), a model of the relationship between the amount (concentration, ratio) of the mixture and the free energy of mixing is predetermined based on Raoult's law. This model is stored in the controller 70. Then, the oil sensor 50 detects the kinematic viscosity of the oil. The controller 70 calculates the value of the free energy of mixing from the kinematic viscosity detected by the oil sensor 50. The value of the free energy of mixing depends on the degree of mixing of the mixture. Therefore, the abnormality detection unit 72 may use the value of the free energy of mixing calculated in this way as an indicator of the degree of mixing (an indicator for abnormality detection) to perform an oil abnormality detection.

[0066] [Example of judgment C3] (Mixture is liquid, judgment based on dielectric constant) The oil sensor 50 detects the dielectric constant of the oil within a predetermined temperature range (e.g., 30°C to 60°C). The controller 70 calculates the average value of the dielectric constant within the predetermined temperature range. The average value of the dielectric constant depends on the degree of contamination of the mixture. Therefore, the abnormality determination unit 72 may use the average value of the dielectric constant as an indicator of the degree of contamination (an indicator for abnormality determination) to determine if there is an abnormality in the oil. This example is also an example of [Example A of Determination] described above.

[0067] [Example of judgment C4] (Mixture is liquid, judgment based on dielectric constant) For oils in various states (including normal and abnormal states), a model of the relationship between the degree of mixing and the dielectric constant can be predetermined from the Maxwell-Garnett model. Here, the Maxwell-Garnett model is applied assuming that the mixture is completely (uniformly) dispersed in the oil, which is the solvent. This model is stored in the controller 70. The oil sensor 50 then detects the dielectric constant of the oil. The abnormality determination unit 72 may then use the dielectric constant as an indicator of the degree of mixing (an indicator for abnormality determination) to determine if the oil is abnormal.

[0068] [Example of judgment C5] (Mixture is solid, judgment based on kinematic viscosity) Similar to the above [Example C1 of Judgment], the controller 70 takes an Arrhenius plot of the kinematic viscosity values ​​detected by the oil sensor 50 within a predetermined temperature range (e.g., 30°C to 60°C) and applies the Arrhenius plot to the Andrade model. This results in outliers that deviate significantly from the Andrade model. Information regarding these outliers (e.g., the amount of deviation from the Andrade model, the number of outliers, etc.) depends on the degree of contamination of the mixture. Therefore, the abnormality determination unit 72 may use the information regarding the outliers as an indicator of the degree of contamination (an indicator for abnormality determination) to perform oil abnormality determination. The reason why the above outliers occur is thought to be as follows: If the mixture is a liquid, the mixture is dispersed in the oil. On the other hand, if the mixture is a solid, it is thought that the mixture is unevenly distributed in the oil (there is an uneven distribution of contaminants). If this mixture clings to the area around the tuning fork of the oil sensor 50, it is thought that the kinematic viscosity detected by the oil sensor 50 will rise sharply. As a result, it is thought that the above outliers occur.

[0069] In step S15, if the abnormality detection unit 72 determines that there is an abnormality in the oil (if the answer in step S14 is YES), the notification unit 81 issues a notification. Specifically, for example, if the abnormality detection unit 72 determines that there is an abnormality in the oil, the notification generation unit 75 generates a notification, and the notification unit 81 outputs the notification generated by the notification generation unit 75. The notification unit 81 may also notify that there is an abnormality in the oil. The notification unit 81 may also notify the details of the abnormality (what kind of abnormality it is). For example, the notification unit 81 may notify that the kinematic viscosity of the oil is higher (or lower) than the normal range, that the oil temperature is higher (or lower) than the normal range, or that the dielectric constant of the oil is higher (or lower) than the normal range. The notification unit 81 may also notify that the degree of mixing of a mixture into the oil is higher (or lower) than the normal range. The notification unit 81 may also notify the operator (the person who receives the notification) to change the oil. The notification unit 81 may notify that oil abnormality control (step S30 described later) will be performed, or it may notify the content of the oil abnormality control (e.g., increasing or decreasing the output). The notification unit 81 may provide notifications by light (e.g., screen display) or by sound (e.g., voice notification). The notification unit 81 may notify the operator of the work machine 10, or it may notify the manager of the work machine 10.

[0070] In step S30, if the abnormality detection unit 72 determines that there is an abnormality in the oil (if the answer is YES in step S14), the operation control unit 76 changes the control of the operation of actuator A from the "normal control" described above (performs a "control change") (abnormality control step). In this case, the operation control unit 76 controls actuator A using "oil abnormality control," which is different from the normal control. The operation control unit 76 may change the content of the oil abnormality control according to the nature of the oil abnormality (what kind of abnormality it is) determined by the abnormality detection unit 72 (described later).

[0071] (Purpose of controlling oil abnormalities) The operation control unit 76 may suppress problems with the work machine 10 (see Figure 1) (e.g., malfunction, poor fuel efficiency, etc.) by performing oil abnormality control. As a result of the operation control unit 76 performing oil abnormality control, it may be possible to inform the operator of the oil abnormality. The oil abnormality may be notified to the operator by at least one of the following: notification from the notification unit 81 and oil abnormality control by the operation control unit 76.

[0072] (Changes to the output) For example, the hydraulic circuit control unit 76b may change the output of the hydraulic actuator 37 by changing the operation control unit 76 from normal control to oil abnormality control (performing a control change). The change in the output of the hydraulic actuator 37 may be to increase the output or to decrease the output. Specifically, for example, the change in the output of the hydraulic actuator 37 may be to change the output of the hydraulic oil pump 32 (see Figure 1) (step S31) (to increase or decrease the output). The change in the output of the hydraulic actuator 37 may also be to change the control of the valve 35 (see Figure 1) (step S32) (to increase or decrease the opening). The change in the output of the hydraulic actuator 37 may also be to change the state of the hydraulic actuator 37 (for example, to increase or decrease the capacity of the hydraulic motor).

[0073] For example, the operation control unit 76 may change the output of the engine 21 by changing from normal control to oil abnormality control (performing a control change), which may cause the engine control unit 76a to change the output of the engine 21 (performing a "change in output" of the engine 21) (step S33). The change in the output of the engine 21 may be to increase the output or to decrease the output. As a result of the change in the output of the engine 21, the output of the hydraulic oil pump 32 (see Figure 1) driven by the engine 21 may also be changed (step S31).

[0074] (Parameters used to determine oil abnormalities) The abnormality detection unit 72 may use one or more parameters to determine oil abnormalities. The parameters used by the abnormality detection unit 72 to determine oil abnormalities include the detected value of the oil sensor 50 (at least one of temperature, kinematic viscosity, and dielectric constant). The parameters used by the abnormality detection unit 72 to determine oil abnormalities may further include values ​​acquired by the oil-related information acquisition unit 63 (for example, at least one of engine water temperature and ambient temperature).

[0075] The following example mainly describes a case where the abnormality detection unit 72 makes an oil abnormality determination based on at least one of the oil temperature and oil kinematic viscosity, and at least one of the engine water temperature and ambient temperature (see Figure 4).

[0076] (Determining whether there are abnormalities when there are multiple parameters) If there are multiple parameters used to determine oil abnormality, the abnormality determination unit 72 determines whether the oil is abnormal based on whether each parameter is within the normal range. For example, the abnormality determination unit 72 may determine that the oil is abnormal if even one of the multiple parameters is outside the normal range. The abnormality determination unit 72 may also determine that the oil is abnormal if the number of parameters for which values ​​outside the normal range have been detected exceeds a certain number. In this case, the "number of parameters" may be weighted for each parameter. For example, parameters that have a greater impact on oil abnormality may be given a larger weight. Specifically, for example, if the abnormality determination unit 72 determines oil abnormality based on oil temperature, oil kinematic viscosity, engine water temperature, and ambient temperature (see Figure 4), the weights for weighting are set in the order of oil temperature and kinematic viscosity, engine water temperature, and ambient temperature. The weight of oil temperature and the weight of oil kinematic viscosity may be equal (or different).

[0077] (Type of abnormality (abnormality on the higher side of the normal range, abnormality on the lower side of the normal range)) The abnormality determination unit 72 is configured with a normal range (threshold) for each parameter used to determine oil abnormalities. The abnormality determination unit 72 is configured with a threshold that serves as the boundary between the normal range and the abnormal range for each parameter used to determine oil abnormalities. For example, if the value of a parameter is lower than the normal range, the abnormality determination unit 72 determines it to be a "low-range abnormality" (e.g., a first abnormality (see Figure 4)). If the value of a parameter is higher than the normal range, the abnormality determination unit 72 determines it to be a "high-range abnormality" (e.g., a second abnormality, a third abnormality (see Figure 4)). Multiple levels of abnormalities higher than the normal range may be configured. For example, the abnormality determination unit 72 may determine it to be a third abnormality if the value of a parameter is higher than the upper limit of the second abnormality (a threshold higher than the upper limit of the normal range) (in the case of an "even higher abnormality" in Figure 4). In the example shown in Figure 4, a third abnormality is configured for the kinematic viscosity of the oil. A third abnormality may also be configured for parameters other than the kinematic viscosity of the oil. Furthermore, abnormalities on the lower end of the normal range may be defined in multiple stages (similar to the "abnormalities on the higher end" stage, an "abnormality on the lower end" stage may also be defined).

[0078] (Oil abnormality control according to the type of abnormality) As described above, the operation control unit 76 shown in Figure 2 may change the content of the oil abnormality control depending on the content of the oil abnormality determination by the abnormality determination unit 72. Specifically, for example, the operation control unit 76 may change the content of the oil abnormality control depending on whether the parameter used for oil abnormality determination is on the higher side of the normal range (e.g., second abnormality, third abnormality) or on the lower side (e.g., first abnormality) (see Figure 4). Hereinafter, the output of at least one of the engine 21 and hydraulic actuator 37 that the operation control unit 76 changes by changing the control from normal control to oil abnormality control will simply be referred to as "output". For example, the operation control unit 76 may change whether to change the control to increase the output or to change the control to decrease the output depending on the content of the oil abnormality.

[0079] Specifically, for example, as shown in Figure 4, when the kinematic viscosity of the oil is in a first abnormal state (an abnormal state lower than the normal range), the operation control unit 76 (see Figure 2) changes the control to reduce the output. In this case, the control change to reduce the output lowers the oil temperature and increases the kinematic viscosity of the oil. Therefore, if the oil is a lubricant, an appropriate oil film is formed between the parts, and wear of the parts can be suppressed. Thus, even if the condition of the oil is abnormal (more specifically, even if the abnormality determination unit 72 determines that it is abnormal), the influence of the oil on the work machine 10 can be suppressed.

[0080] When the kinematic viscosity of the oil is at the second abnormal level (an abnormality that is higher than the normal range but lower than the third abnormal level), the operation control unit 76 (see Figure 2) changes the control to increase the output. In this case, the control change to increase the output raises the oil temperature and lowers the kinematic viscosity of the oil. Therefore, if the oil is a lubricant, it is possible to suppress the large load that would otherwise be placed between the parts due to the high kinematic viscosity of the oil. Thus, even if the condition of the oil is abnormal, the influence of the oil on the work machine 10 (see Figure 1) can be suppressed.

[0081] When the kinematic viscosity of the oil is at the third abnormal level (higher than the second abnormal level), if actuator A (see Figure 2) is operated as is, actuator A may fail. The oil condition at which actuator A may fail if it is operated as is is set as the "third abnormal level." At this time, for example, the kinematic viscosity of the oil is so high that the oil cannot perform its role as a lubricant. As a result, there is a risk of seizure between parts. Therefore, the operation control unit 76 shown in Figure 2 changes the control to reduce the output. Thus, failure of actuator A (working machine 10 (see Figure 1)) can be suppressed.

[0082] As shown in Figure 4, when a temperature-related parameter (at least one of the oil temperature, engine water temperature, and ambient temperature) is in the first abnormal state (lower than the normal range), the oil's kinematic viscosity is higher than in a normal state. This is because, generally, as the oil temperature increases, the oil's kinematic viscosity decreases. Therefore, when a temperature-related parameter is in the first abnormal state, the operation control unit 76 (see Figure 2) changes its control to increase the output. In this case, the oil temperature increases, and the oil's kinematic viscosity decreases. Thus, if the oil is a lubricant, it is possible to suppress the large load placed between parts due to the high kinematic viscosity of the oil, and to suppress the influence of the oil on the work machine 10 (see Figure 1).

[0083] When the temperature parameter is in the second abnormal state (an abnormality higher than the normal range), the kinematic viscosity of the oil is lower than in a normal state. Therefore, the operation control unit 76 (see Figure 2) changes the control to reduce the output. In this case, the oil temperature decreases and the kinematic viscosity of the oil increases. Thus, if the oil is a lubricant, wear on parts can be suppressed and the influence of the oil on the work machine 10 (see Figure 1) can be reduced.

[0084] (Oil abnormality control according to the type of abnormality when there are multiple parameters) If there are multiple parameters used to determine an oil abnormality, the operation control unit 76 may change the content of the oil abnormality control depending on the number and type of parameters for which values ​​outside the normal range have been detected. For example, the controller 70 counts the number of parameters that are determined to "increase output" and the number of parameters that are determined to "decrease output" from among the parameters used to determine an oil abnormality. If the number of parameters determined to "increase output" is greater than the number of parameters determined to "decrease output," the operation control unit 76 (see Figure 2) changes the control to increase output. If the number of parameters determined to "increase output" is the same as or less than the number of parameters determined to "decrease output," the operation control unit 76 changes the control to decrease output (however, this is only if any of the parameters are outside the normal range). This "number of parameters" may be weighted for each parameter (similar to the "determination of abnormality when there are multiple parameters" described above).

[0085] (Changes to the conditions for detecting oil abnormalities) The conditions (abnormality determination conditions, determination method) for the abnormality determination unit 72 shown in Figure 2 to perform oil abnormality determination may be changed depending on certain conditions. For example, the parameters used for oil abnormality determination, the normal range (threshold) of each parameter, or the weights of each parameter may be changed. For example, the conditions for the abnormality determination unit 72 to perform oil abnormality determination may be changed according to the learning results. Specifically, for example, information detected by the oil sensor 50, the abnormality determination conditions currently set in the controller 70, and information on whether past oil changes were necessary are stored in, for example, the server 83. Specifically, the "information on whether oil changes were necessary" is, for example, information indicating whether the actual state of the oil was in a state that required an oil change when the abnormality determination unit 72 determined it to be abnormal. The server 83 then learns the relationship (trend) between the state of the oil and the need for an oil change, such as when the need for an oil change increases. The abnormality determination unit 72 then changes the abnormality determination conditions according to these learning results. Note that the above learning may be performed by parts other than server 83. Also, the anomaly detection unit 72 may change the anomaly detection conditions according to conditions other than the learning results.

[0086] (Count of operation time during abnormal conditions) The abnormal operation time counting unit 73 counts (cumulatively accumulates) the time the operation unit 17 is operated when the abnormality detection unit 72 determines that there is an abnormality in the oil. The abnormal operation time counting unit 73 counts how long the operation unit 17 is operated while there is an abnormality in the oil (while the oil is in poor condition). The abnormal operation time counting unit 73 may transmit the count result (count result) to an external device of the work machine 10, for example, to the notification unit 81 or to the server 83. The notification unit 81 or the server 83 may output the count result to the abnormal operation time counting unit 73. At least one of the controller 70 and the server 83 may perform processing based on the count result.

[0087] (Information security) The security processing unit 85 performs information security processing on the information exchanged in the oil abnormality detection system 1. For example, the information subject to information security processing by the security processing unit 85 may be the detection value of the oil sensor 50, or the information sent from the oil sensor 50 to the controller 70. The information subject to information security processing by the security processing unit 85 may be information obtained based on the detection value of the oil sensor 50, for example, information on whether the oil is abnormal or not, or information indicating the content of the notification unit 81. By providing the security processing unit 85, it is possible to suppress malicious users from tampering with the detection value of the oil sensor 50 or the information obtained based on the detection value. Therefore, it is possible to suppress impersonation, such as pretending that the oil is normal when it is abnormal. The security processing unit 85 may also perform information security processing on other information (information that is different from the detection value of the oil sensor 50 and different from the information obtained based on the detection value).

[0088] The security processing unit 85 may perform processing for detecting tampering with information. For example, the security processing unit 85 may perform processing to attach a code for detecting tampering (such as a message authentication code) to the information and processing to verify the code (the security processing unit 85 may also be a code generation device and a code verification device). For example, if the security processing unit 85 detects that the information has been tampered with, it discards the tampered information and transmits information indicating that tampering has occurred. For example, the security processing unit 85 may transmit information indicating that tampering has occurred to a server 83 owned by the manufacturer or dealer of the work machine 10. The security processing unit 85 may perform processing to deter the theft of information. For example, the security processing unit 85 may encrypt and decrypt the information.

[0089] (Effects of the first invention) The effects of the oil abnormality detection system 1 shown in Figure 2 are as follows. The oil abnormality detection system 1 comprises a hydraulic actuator 37, an oil sensor 50, an abnormality determination unit 72, and an operation control unit 76. Actuator A operates the work machine 10 (see Figure 1) and utilizes oil. The oil sensor 50 detects at least one of the viscosity, kinematic viscosity, temperature, and dielectric constant of the oil. The abnormality determination unit 72 can determine whether or not there is an abnormality in the oil based on the value detected by the oil sensor 50. The operation control unit 76 controls the operation of actuator A. If the abnormality determination unit 72 determines that there is no abnormality in the oil, the operation control unit 76 controls actuator A by predetermined normal control.

[0090] [Configuration 1] If the abnormality detection unit 72 determines that there is an abnormality in the oil, the operation control unit 76 controls the actuator A using an oil abnormality control that is different from normal control (see step S30 in Figure 3).

[0091] As described in [Configuration 1] above, when there is an abnormality in the oil, actuator A is controlled by the oil abnormality control. If the contents of the oil abnormality control are set appropriately, the control of actuator A by the oil abnormality control will suppress problems with actuator A (e.g., failure, poor fuel efficiency, etc.). Therefore, when there is an abnormality in the oil, it is possible to suppress problems with actuator A.

[0092] (Effects of the second invention) [Configuration 2] The oil abnormality detection system 1 includes a notification unit 81. The notification unit 81 notifies when the abnormality determination unit 72 determines that there is an abnormality in the oil (see step S15 in Figure 3).

[0093] With the above configuration [2], the person (worker) who receives the notification from the notification unit 81 can be informed that there is an abnormality in the oil, etc.

[0094] (Effects of the third invention) The oil abnormality detection system 1 comprises an operating unit 17 and an abnormality operation time counting unit 73. The operating unit 17 is operated by an operator and is used to operate actuator A.

[0095] [Configuration 3] The abnormal operation time counting unit 73 counts the time the operation unit 17 is operated when the abnormality determination unit 72 has determined that there is an abnormality in the oil.

[0096] With the above [Configuration 3], it is possible to obtain information about the time the operating unit 17 was operated while there was an abnormality in the oil. For example, this information can be used for notifying the operator or for control purposes.

[0097] (Effects of the fourth invention) [Configuration 4] The oil abnormality detection system 1 includes a security processing unit 85. The security processing unit 85 performs information security processing on at least one of the detected value from the oil sensor 50 and the information obtained based on the detected value.

[0098] The above [Configuration 4] makes it possible to suppress information security issues (such as tampering or theft) related to at least one of the detected values ​​of the oil sensor 50 and the information obtained based on the detected values.

[0099] (Effects of the fifth invention) [Configuration 5] The oil abnormality detection system 1 includes a flow velocity acquisition unit 61 that acquires the oil flow velocity. The abnormality determination unit 72 (see Figure 2) determines whether or not there is an oil abnormality based on the detection value detected by the oil sensor 50 when the oil flow velocity acquired by the flow velocity acquisition unit 61 is within a predetermined flow velocity range (YES in step S11 in Figure 3) (performs step S14 in Figure 3).

[0100] The above [Configuration 5] provides the following effect: The detection accuracy of the oil sensor 50 may vary depending on the oil flow rate. In the above [Configuration 5], the abnormality determination unit 72 (see Figure 2) determines whether or not there is an abnormality in the oil based on the detected value when the oil flow rate is within a predetermined flow rate range. Therefore, if the above "predetermined flow rate range" is set to a flow rate that ensures the detection accuracy of the oil sensor 50, the detection accuracy of the oil sensor 50 can be ensured. Thus, the abnormality determination unit 72 (see Figure 2) can accurately determine whether or not the oil is abnormal.

[0101] (Effects of the sixth invention) [Configuration 6-1a] Actuator A shown in Figure 1 is an internal combustion engine 21. "Oil" is the fuel for the engine 21. The oil abnormality detection system 1 comprises a fuel separator 23c (separator) and a fuel pump 23g (pump). The fuel separator 23c separates the fuel (oil) mixture from the fuel. The fuel pump 23g draws in the fuel.

[0102] [Configuration 6-1b] The oil sensor 50 (more specifically, the fuel sensor 51) is positioned to detect the oil in the fuel passage 23k (oil passage) between the fuel separator 23c and the fuel pump 23g.

[0103] The following effects can be obtained from the above configurations [6-1a] and [6-1b]. In configuration [6-1b], the oil sensor 50 is positioned in the fuel passage 23k at a location where the oil flow velocity is relatively slow. Furthermore, the detection accuracy of the oil sensor 50 can be ensured when the oil flow velocity is lower than a predetermined flow rate. In this case, the detection accuracy of the oil sensor 50 can be ensured by configuration [6-1b]. Therefore, the abnormality determination unit 72 (see Figure 2) can accurately determine whether the oil is abnormal or not.

[0104] [Configuration 6-2a] Actuator A is an internal combustion engine, which is an engine 21. "Oil" is engine oil that lubricates the inside of the engine 21. The oil abnormality detection system 1 comprises an engine oil separator 25c (separator) and an engine oil pump 25g (pump). The engine oil separator 25c separates the mixture from the engine oil (oil). The engine oil pump 25g draws in the engine oil.

[0105] [Configuration 6-2b] The oil sensor 50 (engine oil sensor 53) is positioned to detect the oil in the engine oil passage 25k (oil passage) between the engine oil separator 25c and the engine oil pump 25g.

[0106] The above-described [Configuration 6-2a] and [Configuration 6-2b] provide the same effects as those provided by the above-described [Configuration 6-1a] and [Configuration 6-1b].

[0107] (Effects of the seventh invention) [Configuration 7a] Actuator A is a hydraulic actuator 37 that operates the work machine 10 by hydraulic pressure. Oil is the hydraulic fluid supplied to the hydraulic actuator 37. The oil abnormality detection system 1 comprises a hydraulic fluid tank 31 and a hydraulic fluid filter 39. The hydraulic fluid tank 31 stores the hydraulic fluid (oil). The hydraulic fluid filter 39 separates the mixture from the hydraulic fluid.

[0108] [Configuration 7b] The oil sensor 50 (more specifically, the hydraulic fluid sensor 55) is positioned to detect the hydraulic fluid in the hydraulic fluid passage 41 (oil passage) between the hydraulic fluid filter 39 and the hydraulic fluid tank 31.

[0109] The following effects can be obtained from the above configurations [7a] and [7b]. In configuration [7b], the oil sensor 50 is positioned in the hydraulic fluid passage 41 at a location where the hydraulic fluid flow velocity is relatively slow. In addition, the detection accuracy of the oil sensor 50 can be ensured when the oil flow velocity is lower than a predetermined flow rate. In this case, the detection accuracy of the oil sensor 50 can be ensured by configuration [7b]. Therefore, the abnormality determination unit 72 (see Figure 2) can accurately determine whether the hydraulic fluid is abnormal or not.

[0110] (Effects of the 8th Invention) The effects of the oil abnormality detection method of this embodiment are as follows. The oil abnormality detection method comprises a detection step, an abnormality determination step, a normal control step, and an abnormality control step.

[0111] [Configuration 8] The detection step (step S12 (see Figure 3, the same applies to each of the following steps)) detects at least one of the viscosity, kinematic viscosity, temperature, and dielectric constant of the oil used by actuator A to operate the work machine 10. The abnormality determination step (step S14) determines whether there is an abnormality in the oil based on the detected value in the detection step (step S12). The normal control step controls actuator A by predetermined normal control if the abnormality determination step determines that there is no abnormality in the oil (if NO in step S14). The abnormality control step (step S30) controls actuator A by oil abnormality control, which is different from normal control, if the abnormality determination step determines that there is an abnormality in the oil (if YES in step S14).

[0112] The above [Configuration 8] provides the same effects as described in "(Effects of the First Invention)".

[0113] (Effects of the 9th Invention) The effects of the oil abnormality detection program of this embodiment are as follows: The oil abnormality detection program causes the controller 70 (computer) to execute a detection step, an abnormality determination step, a normal control step, and an abnormality control step.

[0114] [Configuration 9] The detection step (step S12) detects at least one of the viscosity, kinematic viscosity, temperature, and dielectric constant of the oil used by actuator A to operate the work machine 10. The abnormality determination step (step S14) determines whether there is an abnormality in the oil based on the detected value in the detection step (step S12). The normal control step controls actuator A by predetermined normal control if the abnormality determination step determines that there is no abnormality in the oil (if NO in step S14). The abnormality control step (step S30) controls actuator A by oil abnormality control, which is different from normal control, if the abnormality determination step determines that there is an abnormality in the oil (if YES in step S14).

[0115] The above [Configuration 9] provides the same effects as described in "(Effects of the First Invention)".

[0116] (modified version) The above embodiments may be modified in various ways. For example, the number of components (including modified versions) of the above embodiments may be changed, and some components may not be provided. For example, modified versions of the above embodiments may be combined in various ways. For example, the connections of each component shown in Figures 1 and 2 may be changed. For example, what has been described as multiple different members or parts may be treated as a single member or part. For example, what has been described as a single member or part may be provided as multiple different members or parts. For example, various values ​​(setpoints, thresholds) and ranges may be pre-set in the controller 70, or they may be set by manual operation by an operator. For example, various values ​​and ranges may not be changeable, may be changed by manual operation, or may be automatically changed by the controller 70 according to some conditions. For example, the order of steps in the flowchart shown in Figure 3 may be changed, or some steps may not be performed. For example, each component may have only some of its characteristics (function, arrangement, shape, operation, etc.). [Explanation of Symbols]

[0117] 1. Oil Anomaly Detection System 10 Working Machines 17 Control section 21 Engine 23a Fuel Tank 23c Fuel separation device (separation device) 23g Fuel Pump (Pump) 23k Fuel passage (oil passage) 25c Engine oil separator (separator) 25g Engine Oil Pump (Pump) 25k Engine oil passage (oil passage) 37 Hydraulic Actuator 39. Hydraulic oil filter 41. Hydraulic fluid passage (oil passage) 50 Oil Sensor 61 Flow velocity acquisition part 70 Controller (Computer) 72 Abnormality determination section 73 Abnormal Operation Time Counting Unit 76 Operation Control Unit 81 Notification Department 85 Security Processing Unit Actuator A

Claims

1. Actuators that operate machinery and utilize oil, An oil sensor that detects at least one of the viscosity, kinematic viscosity, temperature, and dielectric constant of the oil, An abnormality determination unit capable of determining whether or not there is an abnormality in the oil based on the detected value of the oil sensor, An operation control unit that controls the operation of the actuator, Equipped with, If the abnormality detection unit determines that there is no abnormality in the oil, the operation control unit controls the actuator by predetermined normal control. If the abnormality detection unit determines that there is an abnormality in the oil, the operation control unit controls the actuator using an oil abnormality control that is different from the normal control. The aforementioned oil abnormality control is, Depending on whether the value of the parameter used to determine whether there is an abnormality in the oil is higher or lower than the normal range of the parameter, it is determined whether to change the output of the actuator to increase or decrease it compared to the normal control. When there are multiple parameters, the control system performs either an increase or decrease in the output of the actuator, depending on the number of parameters that are determined to be changed to increase the output and the number of parameters that are determined to be changed to decrease the output. Oil abnormality detection system.

2. The oil abnormality detection system according to Claim 1, An operating unit operated by an operator to operate the actuator, An abnormal operation time counting unit counts the abnormal operation time, which is the time the operating unit was operated while the abnormality detection unit determined that there was an abnormality in the oil. Equipped with, Oil abnormality detection system.

3. An oil abnormality detection system according to claim 1 or 2, The system includes a notification unit that notifies the user if the abnormality detection unit determines that there is an abnormality in the oil. Oil abnormality detection system.

4. An oil abnormality detection system according to any one of claims 1 to 3, The system includes a security processing unit that performs information security processing on at least one of the detected value of the oil sensor and the information obtained based on the detected value. Oil abnormality detection system.

5. An oil abnormality detection system according to any one of claims 1 to 4, The system includes a flow velocity acquisition unit that acquires the flow velocity of the oil, The abnormality determination unit determines whether or not there is an abnormality in the oil based on the detected value detected by the oil sensor when the oil flow velocity acquired by the flow velocity acquisition unit is within a predetermined flow velocity range. Oil abnormality detection system.

6. An oil abnormality detection system according to any one of claims 1 to 5, The actuator is an engine, which is an internal combustion engine. The oil is either the fuel for the engine or engine oil used to lubricate the inside of the engine. A separation device for separating a mixture from the oil, A pump for sucking up the aforementioned oil, Equipped with, The oil sensor is positioned to detect the oil in the oil passage between the separation device and the pump. Oil abnormality detection system.

7. An oil abnormality detection system according to any one of claims 1 to 5, The actuator is a hydraulic actuator that operates the work machine using hydraulic pressure, The oil is the hydraulic fluid supplied to the hydraulic actuator. A hydraulic oil tank for storing the aforementioned oil, A hydraulic oil filter for separating the mixture from the oil, Equipped with, The oil sensor is positioned to detect the oil in the oil passage between the hydraulic oil filter and the hydraulic oil tank. Oil abnormality detection system.

8. A detection step for detecting at least one of the viscosity, kinematic viscosity, temperature, and dielectric constant of the oil used by the actuator that operates the work machine, An abnormality determination step that determines whether or not there is an abnormality in the oil based on the detected value of the detection step, If the abnormality determination step determines that there is no abnormality in the oil, the normal control step involves controlling the actuator by predetermined normal control, If the abnormality determination step determines that there is an abnormality in the oil, the abnormality control step controls the actuator using an oil abnormality control method different from the normal control method. Equipped with, The aforementioned oil abnormality control is, Depending on whether the value of the parameter used to determine whether there is an abnormality in the oil is higher or lower than the normal range of the parameter, it is determined whether to change the output of the actuator to increase or decrease it compared to the normal control. When there are multiple parameters, the control system performs either an increase or decrease in the output of the actuator, depending on the number of parameters that are determined to be changed to increase the output and the number of parameters that are determined to be changed to decrease the output. Oil abnormality detection method.

9. The oil abnormality detection method according to Claim 8, The abnormal operation time count step includes counting the abnormal operation time, which is the time period during which the operating unit used to operate the actuator, operated by an operator, was operated while the abnormality determination step determined that there was an abnormality in the oil. Oil abnormality detection method.

10. A detection step for detecting at least one of the viscosity, kinematic viscosity, temperature, and dielectric constant of the oil used by the actuator that operates the work machine, An abnormality determination step that determines whether or not there is an abnormality in the oil based on the detected value of the detection step, If the abnormality determination step determines that there is no abnormality in the oil, the normal control step involves controlling the actuator by predetermined normal control, If the abnormality determination step determines that there is an abnormality in the oil, the abnormality control step controls the actuator using an oil abnormality control method different from the normal control method. Have the computer run it, The aforementioned oil abnormality control is, Depending on whether the value of the parameter used to determine whether there is an abnormality in the oil is higher or lower than the normal range of the parameter, it is determined whether to change the output of the actuator to increase or decrease it compared to the normal control. When there are multiple parameters, the control system performs either an increase or decrease in the output of the actuator, depending on the number of parameters that are determined to be changed to increase the output and the number of parameters that are determined to be changed to decrease the output. Oil abnormality detection program.

11. An oil abnormality detection program according to claim 10, In the abnormality detection step, if it is determined that there is an abnormality in the oil, the computer is instructed to execute an abnormal operation time counting step, which counts the abnormal operation time, which is the time that the operating unit used to operate the actuator, operated by the operator, was operated for. Oil abnormality detection program.

Images