Management device and management system of working machine

Abstract

A management device and a management system for a work machine are provided, which can improve the precision of determining whether the oil of the drive unit of the work machine has been replaced with genuine oil. The management server manages the oil used in the drive unit of a hydraulic shovel. The management server has an oil replacement history creation unit that acquires a measurement value of the characteristics of the target oil from an oil sensor mounted on the hydraulic shovel and creates a replacement history of the target oil based on a change in the characteristics of the target oil; a worker access history creation unit that acquires access information indicating that a worker has accessed the hydraulic shovel and creates a worker access history of the hydraulic shovel based on the access information; and a oil type determination unit that determines the type of the target oil replaced at the replacement time corresponding to the replacement history based on the replacement history of the target oil and the worker access history.

Description

Technology Field

[0001] The present invention relates to a management device and a management system for a work machine. Background Technology

[0002] A drive unit mounted on a work machine comprises, for example, an engine, a circulation system for circulating engine oil used for lubricating or cooling the engine, a hydraulic pump driven by the engine, and a hydraulic actuator driven by working fluid discharged from the hydraulic pump.

[0003] Patent Document 1 discloses a server computer that collects the characteristics of an oil (specifically, the engine oil and hydraulic fluid described above) used in a drive unit of a working machine and measures the characteristics of the oil using an oil sensor of the working machine. The server computer determines an abnormality in the oil by comparing the characteristics of the oil measured by the oil sensor with a predetermined threshold. Prior art literature

[0004] Japanese Patent Publication No. 6234359 The problem to be solved

[0005] While it is preferable to use genuine oil (in other words, the oil recommended by the machine manufacturer) in the drive system of a work machine, there are cases where non-genuine oil (in other words, the oil not recommended by the machine manufacturer) is used. Determining whether genuine oil is being used in the drive system of a work machine is important, for example, in setting thresholds for detecting oil abnormalities or determining the timing of maintenance.

[0006] One method for a computer to determine whether genuine oil is being used in the drive unit of a working machine is to use the measurement results of an oil sensor. Specifically, the computer determines the oil change timing based on changes in the oil properties measured by the oil sensor. Then, it determines whether the oil in the drive unit of the working machine has been replaced with genuine oil by checking whether the oil properties measured by the oil sensor immediately after replacement are identical to those of genuine oil.

[0007] However, the aforementioned method presents a challenge in terms of judgment precision. Specifically, even with oil immediately after replacement, variations in properties occur due to individual differences in the oil or the influence of residual oil. Consequently, when the properties of genuine oil and non-genuine oil are similar, it is difficult to distinguish between them.

[0008] The objective of the present invention is to provide a management device and a management system for a work machine that can improve the precision of determining whether the oil of the drive unit of the work machine has been replaced with genuine oil. means of solving the problem

[0009] To achieve the above objective, the present invention, a representative invention, comprises a management device for managing oil used in a drive unit of a work machine, wherein the device includes: an oil exchange history creation unit that acquires a measurement value of the properties of a target oil from an oil sensor mounted on the work machine and creates an exchange history of the target oil based on a change in the properties of the target oil; an operator access history creation unit that acquires access information indicating that an operator has accessed the work machine and creates an access history of the operator to the work machine based on the access information; and an oil type determination unit that determines the type of the target oil exchanged at an exchange time corresponding to the exchange history based on the exchange history of the target oil and the access history of the operator. Effects of the invention

[0010] According to the present invention, the precision of determining whether the oil of a work machine's drive unit has been replaced with genuine oil can be improved. Brief explanation of the drawing

[0011] FIG. 1 is a block diagram showing the configuration of a management system in one embodiment of the present invention. FIG. 2 is a side view showing the structure of a hydraulic shovel in one embodiment of the present invention. FIG. 3 is a schematic diagram showing the configuration of a driving device for a hydraulic shovel in one embodiment of the present invention. FIG. 4 is a diagram illustrating the determination of the oil change timing by the management controller of the management server in one embodiment of the present invention. FIG. 5 is a diagram illustrating the determination of oil excess by the management controller of the management server in one embodiment of the present invention. FIG. 6 is a flowchart showing part of the processing procedure regarding the determination of the type of oil by the management controller of the management server in one embodiment of the present invention. FIG. 7 is a flowchart showing part of the processing procedure for determining the type of oil by the management controller of the management server in one embodiment of the present invention. Specific details for implementing the invention

[0012] One embodiment of the present invention will be described with reference to the drawings. In addition, in this embodiment, a hydraulic shovel is used as an example of a working machine.

[0013] FIG. 1 is a block diagram showing the configuration of a management system in the present embodiment. FIG. 2 is a side view showing the structure of a hydraulic shovel in the present embodiment. FIG. 3 is a schematic diagram showing the configuration of a driving device for a hydraulic shovel in the present embodiment. In addition, FIG. 3 shows only the configuration regarding the driving of a boom cylinder among the configurations regarding the driving of a plurality of hydraulic actuators (specifically, a plurality of control valves, etc.) for convenience, but the configurations regarding the driving of other hydraulic actuators are the same.

[0014] The management system of the present embodiment comprises a hydraulic shovel (1), a terminal (2) owned by a worker performing maintenance on the hydraulic shovel (1), and a management server (3) owned by the manufacturer of the hydraulic shovel (1). A body controller (4) mounted on the hydraulic shovel (1), the terminal (2) for the worker, and the management server (3) can communicate with each other through a communication network (5).

[0015] A hydraulic shovel (1) comprises a drivable lower body (6), an upper body (7) rotatably provided on the upper side of the lower body (6), and a work device (8) connected to the upper body (7). The lower body (6) is driven by the rotation of a driving motor (not shown), and the upper body (7) is rotated by the rotation of a rotation motor (not shown).

[0016] The working device (8) comprises a boom (9) rotatably connected to an upper pivot body (7), an arm (10) rotatably connected to the tip of the boom (9), and a bucket (11) rotatably connected to the tip of the arm (10). The boom (9) rotates by the extension and retraction of a boom cylinder (12), the arm (10) rotates by the extension and retraction of an arm cylinder (13), and the bucket (11) rotates by the extension and retraction of a bucket cylinder (14).

[0017] The hydraulic shovel (1) is equipped with a positioning device that measures its own position, although not shown. This positioning device has, for example, an antenna that receives a signal from a satellite and measures its own position based on the signal from the satellite.

[0018] The driving device (15) of the hydraulic shovel (1) comprises an engine (16), a circulation system (17) that circulates engine oil used for lubrication or cooling of the engine (16), a hydraulic pump (18) driven by the engine (16), a plurality of hydraulic actuators (specifically, the aforementioned driving motor, slewing motor, boom cylinder (12), arm cylinder (13) and bucket cylinder (14)) driven by the hydraulic fluid discharged from the hydraulic pump (18), a plurality of control valves (19) that each control the flow of hydraulic fluid from the hydraulic pump (18) to the plurality of hydraulic actuators, and a plurality of operating devices (not shown) for operating the plurality of control valves (19).

[0019] In this embodiment, the oil sensor (20A) is provided in the flow path between, for example, the boom cylinder (12) and the control valve (19) to measure the properties of the working oil (specifically, at least one of, for example, viscosity, density, dielectric constant, color, and particle concentration). The oil sensor (20B) is provided in the circulation system (17) to measure the properties of the engine oil.

[0020] The body controller (4) of the hydraulic shovel (1) has a processor that executes processing according to a program, although not shown, and a memory that stores programs or data. The body controller (4) temporarily stores in memory the characteristics of the hydraulic fluid measured by the oil sensor (20A), the characteristics of the engine oil measured by the oil sensor (20B), and the position of the hydraulic shovel (1) measured by the positioning device, and transmits to the management server (3) at a predetermined period.

[0021] The terminal (2) for the worker, although not shown, has a processor that executes processing according to a program, a memory that stores programs or data, and an interface capable of input or display. In addition, the terminal (2) has a function to measure its own position, almost like the positioning device of the hydraulic shovel (1), and transmits the position of the terminal (2) to the management server (3).

[0022] The management server (3) of the present embodiment targets the oil (specifically, the engine oil and hydraulic oil described above) used in the drive device (15) of the hydraulic shovel (1), and has the function of collecting the characteristics of the oil measured by the oil sensors (20A, 20B) of the hydraulic shovel (1), and corresponds to the management device described in the claims. Hereinafter, the oil that is the subject of measurement by the oil sensors (20A or 20B) (i.e., the oil that is the subject of management) may be referred to as the target oil, and in the present embodiment, the hydraulic oil or engine oil is the target oil.

[0023] The management server (3) is equipped with a management controller (21) and a memory device (22). The management controller (21), although not shown, has a processor that executes processing according to a program and a memory that stores programs or data. The memory of the management controller (21) temporarily stores time-series data on the properties of hydraulic fluid or time-series data on the properties of engine oil obtained from the vehicle body controller (4). The processor of the management controller (21) processes the data stored in the memory and stores the data created by the processing in the memory device (22).

[0024] The memory device (22) is, for example, a hard disk that builds a database and stores data of the hydraulic shovel (1) acquired from the body controller (4) (specifically, operation data of the hydraulic shovel (1), etc.), data acquired from the terminal (2) for the worker (specifically, work reports or parts purchase history for the hydraulic shovel (1), etc.), data created by the management controller (21) (specifically, oil change history for the hydraulic shovel (1) or access history of the worker), and data of multiple types of oil acquired in advance (specifically, characteristics of the new condition of the genuine oil, or thresholds of characteristics pre-set for each oil type for determining abnormalities of the genuine oil or non-genuine oil, etc.).

[0025] The management controller (21) has, as a functional configuration, an oil change history creation unit (23), a worker access history creation unit (24), an oil type determination unit (25), and an oil abnormality determination unit (26).

[0026] The oil change history creation unit (23) of the management controller (21) determines the timing for changing the hydraulic fluid of the driving device (15) of the hydraulic shovel (1) using time series data of the hydraulic fluid obtained from the vehicle body controller (4). Specifically, as shown in FIG. 4, the amount of change (A) in the properties of the hydraulic fluid (wherein density is shown as an example in FIG. 4, but other properties may be used) n -A n-1 When ) exceeds a predetermined value (specifically, a value preset considering the degradation of the operating fluid or the measurement error of the oil sensor), time T n-1 From time T n It is determined that the period up to this point is the time for changing the hydraulic fluid (i.e., the target oil, the hydraulic fluid, has been changed during this period). Then, a history of changing the hydraulic fluid for the hydraulic shovel (1) (e.g., the date of oil change) is created and stored in the memory device (22).

[0027] The oil change history creation unit (23) of the management controller (21) uses time-series data of engine oil obtained from the vehicle body controller (4) to determine the timing for changing the engine oil of the driving device (15) of the hydraulic shovel (1) (i.e., when the target oil, the engine oil, is changed at this time). Then, it creates an engine oil change history for the hydraulic shovel (1) and stores it in the memory device (22).

[0028] The worker access history creation unit (24) of the management controller (21) acquires information (access information) indicating that a specified worker (e.g., a worker performing service work) has accessed (contacted or approached) the hydraulic shovel (1). In this embodiment, the worker access history creation unit (24) acquires time-series data of the position of the hydraulic shovel (1) from the vehicle body controller (4) and time-series data of the position of the terminal (2) from the terminal (2) for the worker, respectively, as worker access information. Then, the worker access history creation unit (24) uses this access information to determine the time of the worker's access to the hydraulic shovel (1). In other words, this access information is information indicating that the worker is performing work on the hydraulic shovel (1) (work machine) and has accessed (contacted or approached with intent) the hydraulic shovel (1) in order to perform work.

[0029] Specifically, first, the distance between the hydraulic shovel (1) and the terminal (2) is calculated, and whether the worker is accessing the hydraulic shovel (1) is determined based on whether this distance is within a predetermined value (e.g., 2m). Then, the worker's access history to the hydraulic shovel (1) (e.g., the date of the worker's access and the time of the worker's access on that day) is created and stored in the memory device (22).

[0030] The oil type determination unit (25) of the management controller (21) determines the type of hydraulic oil based on the replacement history of the hydraulic oil (target oil) for the hydraulic shovel (1) described above and the access history of the operator. In this embodiment, the oil type determination unit (25) determines whether the hydraulic oil of the drive device (15) of the hydraulic shovel (1) has been replaced with a predetermined genuine oil (e.g., genuine oil A or B, etc.) (details will be described later). Then, in relation to the replacement history of the hydraulic oil, the type of hydraulic oil (e.g., genuine oil A or B, non-genuine oil, etc.) is stored in the memory device (22).

[0031] The oil abnormality determination unit (26) of the management controller (21) reads the threshold of the characteristics corresponding to the type of hydraulic fluid of the driving device (15) of the hydraulic shovel (1) from the memory device (22). Then, it determines the abnormality of the hydraulic fluid by comparing the time series data of the characteristics of the hydraulic fluid obtained from the body controller (4) of the hydraulic shovel (1) with the threshold. That is, the oil abnormality determination unit (26) determines whether there is an abnormality in the hydraulic fluid based on the threshold according to the type of hydraulic fluid (target oil) determined by the oil type determination unit (25).

[0032] To explain in detail, the oil abnormality determination unit (26) of the management controller (21) reads the corresponding upper threshold SAh and lower threshold SAl of viscosity, upper threshold SBh of density, and upper threshold SCh of dielectric constant from the memory device (22) when the hydraulic fluid of the driving device (15) of the hydraulic shovel (1) is genuine oil A. Then, as shown in FIG. 5, if the viscosity of the hydraulic fluid measured by the oil sensor (20A) exceeds the upper threshold SAh, it is determined to be abnormal. Or, if the viscosity of the hydraulic fluid measured by the oil sensor (20A) falls below the lower threshold SAl, it is determined to be abnormal. Also, if the density of the hydraulic fluid measured by the oil sensor (20A) exceeds the upper threshold SBh, it is determined to be abnormal. Also, as shown in FIG. 5, if the dielectric constant of the hydraulic fluid measured by the oil sensor (20A) exceeds the upper threshold SCh, it is determined to be abnormal.

[0033] The oil type determination unit (25) of the management controller (21) determines the type of engine oil based on the replacement history of the engine oil (target oil) for the hydraulic shovel (1) and the access history of the operator. In this embodiment, the oil type determination unit (25) determines whether the engine oil of the drive unit (15) of the hydraulic shovel (1) has been replaced with a predetermined genuine oil (e.g., genuine oil C or D, etc.). Then, in relation to the engine oil replacement history, the type of engine oil (e.g., genuine oil C or D, non-genuine oil, etc.) is stored in the memory device (22).

[0034] The oil abnormality determination unit (26) of the management controller (21) reads the threshold of the characteristics corresponding to the type of engine oil of the driving device (15) of the hydraulic shovel (1) from the memory device (22). Then, the engine oil abnormality is determined by comparing the time series data of the characteristics of the engine oil obtained from the body controller (4) of the hydraulic shovel (1) with the threshold. That is, the oil abnormality determination unit (26) determines whether there is an abnormality in the engine oil based on the threshold according to the type of engine oil (target oil) determined by the oil type determination unit (25).

[0035] Next, the processing procedure regarding the determination of the oil type by the management controller (21) of the management server (3) of the present embodiment will be explained using FIGS. 6 and 7. FIGS. 6 and 7 are flowcharts showing the processing procedure regarding the determination of the oil type by the management controller of the management server in the present embodiment. Here, engine oil or hydraulic fluid is collectively referred to as "target oil" for description.

[0036] In step S1, the oil type determination unit (25) of the management controller (21) determines whether the replacement history of the target oil for the hydraulic shovel (1) has been updated. If the replacement history of the target oil for the hydraulic shovel (1) has been updated, the process proceeds to step S2.

[0037] In step S2, the oil type determination unit (25) of the management controller (21) determines whether the timing of changing the target oil for the hydraulic shovel (1) (e.g., the oil change date) and the timing of access by the worker (e.g., the worker access date) overlap.

[0038] If the timing of the oil change for the hydraulic shovel (1) and the timing of the access by the worker do not overlap, proceed to step S3. In step S3, the oil type determination unit (25) of the management controller (21) transmits a confirmation notification to a terminal (not shown) held by the user of the hydraulic shovel (1). By doing so, for example, it confirms whether the user has performed the oil change operation.

[0039] Meanwhile, if the timing of the oil change for the hydraulic shovel (1) and the timing of the worker's access overlap, the process proceeds to step S4. In step S4, the oil type determination unit (25) of the management controller (21) determines whether the time of the worker's access to the hydraulic shovel (1) is longer than a predetermined time (specifically, a value pre-set considering the time required for the oil change operation, for example, 0.5 hours).

[0040] If the worker's access time to the hydraulic shovel (1) is less than a predetermined time, proceed to step S3. In step S3, the oil type determination unit (25) of the management controller (21) transmits a confirmation notification to the terminal (2) for the worker. By doing so, for example, it confirms whether the worker has added oil.

[0041] Meanwhile, if the access time of the operator to the hydraulic shovel (1) is longer than a predetermined time, the process proceeds to step S5. In step S5, the oil type determination unit (25) of the management controller (21) extracts the characteristics of the target oil immediately after replacement (An in FIG. 4) from the time series data of the characteristics of the target oil obtained from the vehicle body controller (4). Then, it determines whether the characteristics of the target oil immediately after replacement are similar to the characteristics of the new state of the genuine oil stored in the memory device (22) (in other words, whether the difference in characteristics is less than or equal to a predetermined value).

[0042] If the characteristics of the target oil immediately after replacement are similar to the characteristics of the genuine oil in its new state, the process proceeds to Step S6. In Step S6, the oil type determination unit (25) of the management controller (21) determines that the target oil of the driving device (15) of the hydraulic shovel (1) has been replaced with genuine oil. Then, the type of the target oil is stored in the memory device (22) in relation to the replacement history of the target oil.

[0043] Meanwhile, if the characteristics of the target oil immediately after replacement are not similar to the characteristics of the genuine oil in its new condition, the process proceeds to step S7. In step S7, the oil type determination unit (25) of the management controller (21) determines whether there is information on the purchase of genuine oil in the work report for the hydraulic shovel (1) for the day (in other words, the day the target oil is replaced, the day the worker accesses it) or in the parts purchase history prior to the day, which is stored in the memory device (22).

[0044] If there is information on the purchase of genuine oil in the work report of the day or the parts purchase history prior to the day stored in the memory device (22), proceed to step S8. In step S8, the oil type determination unit (25) of the management controller (21) determines that the oil to be replaced is likely genuine oil, but the measurement value of the oil sensor is abnormal, and transmits a request for maintenance of the hydraulic shovel (1) to the terminal (2) for the worker. Additionally, the cause of the abnormality in the measurement value of the oil sensor is, for example, the influence of residual oil or a fault in the sensor. That is, in this case, it can be considered that, for example, the sensor is normal but the ratio of new oil to genuine oil is low, or a fault has occurred in the sensor.

[0045] Meanwhile, if there is no information on the purchase of genuine oil in the work report of the day or the parts purchase history prior to the day stored in the memory device (22), proceed to step S9. In step S9, the oil type determination unit (25) of the management controller (21) transmits a request for a response to the terminal (2) for the worker regarding whether the target oil of the drive device (15) of the hydraulic shovel (1) has been replaced with genuine oil. Then, in step S10, the oil type determination unit (25) of the management controller (21) determines whether there is a response indicating that the target oil of the drive device (15) of the hydraulic shovel (1) has been replaced with genuine oil. That is, in this case, the oil type determination unit (25) performs a confirmation of the replacement of the target oil with the worker before determining the type of the target oil replaced at the time of replacement.

[0046] If there is a reply indicating that the target oil of the drive device (15) of the hydraulic shovel (1) has been replaced with genuine oil, the process proceeds to step S8. In step S8, the oil type determination unit (25) of the management controller (21) determines that the target oil replaced at the time of replacement is likely genuine oil, but the measurement value of the oil sensor is abnormal, and transmits a request for maintenance of the hydraulic shovel (1) to the terminal (2) for the worker.

[0047] Meanwhile, if there is a response indicating that the target oil of the driving device (15) of the hydraulic shovel (1) has been replaced with non-genuine oil, the process proceeds to step S11. In step S11, the oil type determination unit (25) of the management controller (21) determines that the target oil of the driving device (15) of the hydraulic shovel (1) has been replaced with non-genuine oil. Then, in relation to the replacement history of the target oil, the type of the target oil (non-genuine oil) is stored in the memory device (22).

[0048] As described above, in this embodiment, it is determined whether the target oil of the driving device (15) of the hydraulic shovel (1) has been replaced with genuine oil based not only on the measurement result of the oil sensor of the hydraulic shovel (1) but also on the access history of the operator to the hydraulic shovel (1). Therefore, the precision of determining whether the target oil of the driving device (15) of the hydraulic shovel (1) has been replaced with genuine oil can be improved. As a result, the precision of determining abnormalities in the target oil or determining the maintenance timing can be improved.

[0049] In addition, in the above embodiment, the case in which the management controller (21) of the management server (3) has an oil change history creation unit (23), a worker access history creation unit (24), and a fuel type determination unit (25) has been described as an example, but is not limited thereto. For example, the body controller (4) of the hydraulic shovel (1) may have an oil change history creation unit (23), and the management controller (21) of the management server (3) may have a worker access history creation unit (24) and a fuel type determination unit (25). Alternatively, for example, the body controller (4) of the hydraulic shovel (1) may have an oil change history creation unit (23) and a worker access history creation unit (24), and the management controller (21) of the management server (3) may have a fuel type determination unit (25).

[0050] In addition, in the above embodiment, the hydraulic shovel (1) is equipped with a positioning device that measures its own position, and a terminal (2) for a worker has a function that measures its own position. Based on the position of the hydraulic shovel (1) and the position of the terminal (2), the worker access history creation unit (24) creates the worker access history for the hydraulic shovel (1), but this is not limited thereto. For example, the worker may possess an RFID tag, and the hydraulic shovel (1) may be equipped with a receiver that receives radio waves from the RFID and detects RFID access. Based on the information regarding RFID access to the hydraulic shovel (1) described above, the worker access history creation unit (24) may create the worker access history for the hydraulic shovel (1).

[0051] Furthermore, although the above description uses the case where the working machine is a hydraulic shovel as an example, it is not limited thereto and may be, for example, a dump truck, wheel loader, bulldozer, forklift, or crane. In addition, although the description uses the case where both hydraulic fluid and engine oil are used in the drive unit of the working machine as an example, it is not limited thereto and may be only one of the hydraulic fluid or engine oil, or may be another oil. In other words, the oil subject to management (target oil) can be various oils. In such cases, various information can be obtained from the working machine equipped with an oil sensor capable of measuring the properties of the target oil. Explanation of the symbols

[0052] 1: Hydraulic shovel (working machine) 2: Terminal 3: Management Server (Management Device) 15: Driving device 20A, 20B: Oil sensor 23: Oil Change History Log 24: Worker Access History Creation Section 25: Judgment Division

Claims

Claim 1 A management device for managing oil used in a drive unit of a work machine, characterized by having: an oil exchange history creation unit that acquires a measurement value of the properties of a target oil from an oil sensor mounted on the work machine and creates an exchange history of the target oil based on a change in the properties of the target oil; an access information that indicates that the worker has accessed the work machine based on the location of the work machine and location information of a terminal held by the worker, or information on the access of an RFID held by the worker to the work machine, and creates an access history of the worker to the work machine based on the access information; and an oil type determination unit that determines the oil type of the target oil exchanged at the exchange time based on the properties of the target oil measured by the oil sensor when the exchange time included in the exchange history of the target oil overlaps with the access time included in the access history of the worker. Claim 2 A management device for a work machine according to claim 1, wherein the oil type determination unit determines that the target oil exchanged at the exchange time is the genuine oil when the exchange time of the target oil and the access time of the worker overlap, the access time of the worker is longer than a predetermined time, and the characteristics of the target oil measured by the oil sensor after the exchange time correspond to the characteristics of a predetermined genuine oil. Claim 3 In paragraph 2, the oil type determination unit acquires information regarding the existence of a work report by the worker for the work machine or the existence of purchase information for the genuine oil when the exchange time of the target oil and the access time of the worker overlap, the access time of the worker is longer than the predetermined time, and the characteristics of the target oil measured by the oil sensor after the exchange time do not correspond to the characteristics of the genuine oil, and if the work report or the purchase information for the genuine oil exists, it determines that the target oil exchanged at the exchange time may be genuine oil, but the measurement value of the oil sensor is abnormal. Claim 4 A management device for a work machine according to paragraph 3, wherein the oil type determination unit transmits a request for a response regarding whether the target oil was replaced with the genuine oil to a terminal held by the worker before determining the oil type of the target oil replaced at the replacement time, in the case where the work report or the purchase information of the genuine oil is not available. Claim 5 A management device for a work machine according to claim 4, wherein the oil type determination unit determines that the target oil exchanged at the exchange time is the non-genuine oil when there is a reply from the terminal of the worker stating that the target oil has been exchanged with a predetermined non-genuine oil. Claim 6 A management device for a work machine, characterized in that, in any one of claims 1 to 5, it has an oil abnormality determination unit that determines whether there is an abnormality in the target oil based on a threshold according to the oil type of the target oil determined by the oil type determination unit. Claim 7 A management system capable of communicating with a work machine equipped with a drive unit and an oil sensor for measuring the properties of the oil used in the drive unit, and a management unit for managing the oil used in the drive unit, wherein the management unit comprises: an oil exchange history creation unit that acquires a measured value of the properties of a target oil from the oil sensor and creates an exchange history of the target oil based on a change in the properties of the target oil; an access information indicating that the worker has accessed the work machine based on the location of the work machine and location information of a terminal held by the worker, or access information of an RFID held by the worker regarding the work machine, and creates an access history of the worker to the work machine based on said access information; an oil type determination unit that determines the oil type of the target oil exchanged at the exchange time based on the properties of the target oil measured by the oil sensor when the exchange time included in the exchange history of the target oil and the access time included in the access history of the worker overlap; and an amount of the target oil according to a threshold based on the oil type of the target oil determined by the oil type determination unit. A management system for a work machine characterized by having an oil abnormality determination unit that determines the presence or absence of oil.

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