Work machine, work machine control method and work machine control system

Abstract

A work machine is provided with: a pivotal bearing; a driving device for driving the pivotal bearing; a detection unit that detects a state of at least one of an input to the drive device and an output from the drive device; and a determination unit that determines the state of the pivotal bearing on the basis of the detection value detected by the detection unit.

Description

Technical Field

[0001] The present disclosure relates to the state of a work machine, and more particularly to a technique for determining the state of a slewing bearing. Background Art

[0002] Generally, the inspection of the wear amount of the slewing bearing in a work machine is regularly carried out in accordance with the passage of the operation time of the work machine. If it is found that the wear amount of the slewing bearing exceeds the allowable value, it is judged that it is the replacement period (inspection period) of the slewing bearing.

[0003] In this regard, a method of estimating the wear amount of the slewing bearing by measuring the vibration, sound, etc. of the slewing bearing with a sensor has been proposed (see Patent Document 1).

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2021-147772 Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] On the other hand, the sensor provided in the slewing bearing is easily affected by interference, and it is difficult to determine the state of the slewing bearing with high precision.

[0009] An object of the present disclosure is to provide a work machine, a control method of a work machine, and a control system of a work machine capable of determining the state of a slewing bearing with high precision.

[0010] Means for Solving the Problems

[0011] A work machine according to an aspect of the present disclosure includes: a slewing bearing; a drive device that drives the slewing bearing; a detection unit that detects the state of at least one of the input to the drive device and the output from the drive device; and a determination unit that determines the state of the slewing bearing based on the detection value detected by the detection unit.

[0012] A control method of a work machine according to an aspect of the present disclosure includes: a step of driving a slewing bearing; a step of detecting the state of at least one of the input to the device that drives the slewing bearing and the output from the drive device; and a step of determining the state of the slewing bearing based on the detected detection value.

[0013] A control system of a work machine according to an aspect of the present disclosure includes: a slewing bearing; a drive device that drives the slewing bearing; a detection unit that detects the state of at least one of the input to the drive device and the output from the drive device; and a determination unit that determines the state of the slewing bearing based on the detection value detected by the detection unit.

[0014] Advantages of the Invention

[0015] The work machine, control method of the work machine, and control system of the work machine according to the present disclosure can accurately determine the state of the slewing bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a side view of the work machine according to Embodiment 1.

[0017] Figure 2 is a top view of the work machine according to Embodiment 1.

[0018] Figure 3 is a diagram for explaining the main part of the slewing device according to Embodiment 1.

[0019] Figure 4 is a diagram for explaining the slewing ring 220 according to Embodiment 1.

[0020] Figure 5 Explain the schematic block diagram showing the structure of the slewing system of the work machine according to Embodiment 1.

[0021] Figure 6 is a flowchart for explaining the abnormality determination of the slewing bearing of the controller 10 according to Embodiment 1.

[0022] Figure 7 is a diagram for explaining the change and frequency characteristics of the hydraulic pressure values of the hydraulic sensors 242 and 244, that is, the motor pressure, in the normal slewing bearing according to Embodiment 1.

[0023] Figure 8 is a diagram for explaining the change and frequency characteristics of the hydraulic pressure values of the hydraulic sensors 242 and 244, that is, the first and second motor pressures, in the abnormal slewing bearing according to Embodiment 1.

[0024] Figure 9 is a diagram for explaining the comparison determination of the abnormality of the slewing bearing according to Embodiment 1.

[0025] Figure 10 Explain the schematic block diagram showing the structure of the slewing system of the work machine according to the modification example of Embodiment 1.

[0026] Figure 11 is a flowchart for explaining the abnormality determination of the slewing bearing of the controller 10A according to the modification example of Embodiment 1.

[0027] Figure 12 is a diagram for explaining the calculation table showing the relationship between the first motor pressure and the wear amount according to the modification example of Embodiment 1.

[0028] Figure 13 Explain the schematic block diagram of the structure of the slewing system of the construction machine based on Embodiment 2.

[0029] Figure 14 It is a flowchart for explaining the abnormality determination of the slewing bearing of the controller 10B based on Embodiment 2.

[0030] Figure 15 It is a diagram for explaining the motor pressure and slewing angle data that change with the passage of time based on Embodiment 2.

[0031] Figure 16 It is a diagram for explaining the estimation of the wear position by the wear position estimation unit 22 based on Embodiment 2.

[0032] Figure 17 Explain the schematic block diagram showing the structure of the slewing system of the construction machine based on Embodiment 3.

[0033] Figure 18 It is a diagram for explaining the data table generated by the aggregation department 24 based on Embodiment 3.

[0034] Figure 19 It is a diagram for explaining the change in the amount of wear based on Embodiment 3.

[0035] Figure 20 It is a diagram for explaining the change in the wear range based on Embodiment 3.

[0036] Figure 21 It is a diagram for explaining the mapping of the wear position based on Embodiment 3.

[0037] Figure 22 It is a diagram for explaining the slewing ring based on other embodiments. Specific Embodiments

[0038] Hereinafter, the embodiments will be described with reference to the drawings. In the following description, the same reference numerals are given to the same components. Their names and functions are the same. Therefore, detailed descriptions thereof will not be repeated.

[0039] (Embodiment 1)

[0040] <Overall Structure of the Construction Machine>

[0041] Figure 1 It is a side view of the construction machine based on Embodiment 1.

[0042] Figure 2 It is a top view of the construction machine based on Embodiment 1.

[0043] As Figure 1and Figure 2 As shown in Figure 2 , the hydraulic excavator 200 as a construction machine includes a lower traveling body 210, a slewing ring 220, and an upper slewing body 230. Hereinafter, the direction of the gravitational force in the state where the construction machine is disposed on a horizontal plane is referred to as the "vertical direction". In addition, the front of the driver's seat in the cab 231 described later is simply referred to as the "front", and the rear is simply referred to as the "rear".

[0044] The lower traveling body 210 has a pair of left and right crawlers 211, 211, and these crawlers 211, 211 are driven by traveling hydraulic motors (not shown), whereby the hydraulic excavator 200 travels.

[0045] The slewing bearing is a member that connects the lower traveling body 210 and the upper slewing body 230 in a rotatable manner, and includes a slewing ring 220 and a slewing pinion 223.

[0046] The slewing ring 220 includes an outer ring 221 and an inner ring 222.

[0047] The outer ring 221 is fixed to the upper slewing body 230. The inner ring 222 is supported by the lower traveling body 210 and is annular with a rotation axis L extending in the vertical direction as the center. The outer ring 221 is a coaxial annular member with the inner ring 222 and is disposed outside the inner ring 222. The outer ring 221 is supported so as to be rotatable relative to the inner ring 222 about the rotation axis L. The slewing motor 239 that rotates the slewing pinion 223 is fixed to the upper slewing body 230. When the slewing pinion 223 transmits a rotational force to the inner ring 222, the inner ring side fixed to the lower traveling body provided on the ground and having a large frictional resistance maintains a stopped state. Through the rolling elements 241, the slewing pinion 223 fixed to the outer ring 221 side where the frictional resistance in the slewing direction is reduced rotates. Specifically, the slewing pinion 223 rotates relative to the inner ring 222, and the outer ring 221 rotates relative to the inner ring 222 via the slewing pinion 223 and the upper slewing body 230.

[0048] The upper slewing body 230 is configured to be rotatable relative to the lower traveling body 210 about the rotation axis L by being supported by the outer ring 221. The upper slewing body 230 includes a cab 231 and a working device 232.

[0049] The cab 231 is disposed on the front left side of the upper slewing body 230, and a driver's seat for an operator is provided. The working device 232 is provided so as to extend forward of the upper slewing body 230, and includes a boom 233, an arm 234, and a bucket 235. The working device 232 performs various operations such as excavation by driving the boom 233, the arm 234, and the bucket 235 by respective hydraulic cylinders (not shown).

[0050] The hydraulic pump 238 is driven by the engine 236. The hydraulic drive rotates the swing motor 239, the travel hydraulic motor, and each hydraulic cylinder by the drive of the hydraulic pump 238.

[0051] The output of the swing motor 239 is transmitted to the swing pinion 223 fixed to the rotating shaft of the swing motor 239 to rotate the swing pinion 223. Further, the output of the swing motor 239 is transmitted to the inner ring 222 via the internal teeth of the inner ring 222 that mesh with the teeth of the swing pinion 223. Thus, as described above, the swing pinion 223 rotates relative to the inner ring 222, and the outer ring 221 rotates relative to the inner ring 222 via the swing pinion 223 and the upper swing body 230.

[0052] Figure 3 This is a diagram for explaining the main part of the swing device according to Embodiment 1. Refer to Figure 3 , the swing device includes a swing motor 239, a swing pinion 223, and a swing ring 220.

[0053] Figure 4 This is a diagram for explaining the swing ring 220 according to Embodiment 1.

[0054] In Figure 4 of (A), an enlarged cross-sectional view of the swing ring 220 is shown.

[0055] Figure 4 of (B) shows an external view of the swing ring 220.

[0056] Refer to Figure 4 of (A) and (B), the swing ring 220 has an inner ring 222, an outer ring 221, and rolling elements 241.

[0057] The rolling elements 241 are held and arranged between the inner ring 222 and the outer ring 221 so as to be able to roll.

[0058] The swing pinion 223 is arranged to mesh with the internal teeth of the inner ring 222. The outer ring 221 rotates relative to the inner ring 222 via the swing pinion 223 and the upper swing body 230.

[0059] <Structure of Swing System>

[0060] Figure 5 An outline block diagram of the structure of the swing system of the work machine according to Embodiment 1 will be described.

[0061] As Figure 5 shown, the swing system of the work machine includes an engine 236, a hydraulic pump 238, a valve 240, a swing motor 239, and a swing pinion 223.

[0062] The hydraulic pump 238 is driven by the engine 236.

[0063] Hydraulic pressure is supplied from the hydraulic pump 238 to the swing motor 239 via the valve 240. The output of the swing motor 239 is transmitted to the inner ring 222 via the swing pinion 223. Then, the upper swing body 230 rotates.

[0064] In this example, a hydraulic sensor 242 for measuring the hydraulic pressure on the inlet (IN) side where the working oil is supplied to the swing motor 239, and a hydraulic sensor 244 for measuring the hydraulic pressure on the outlet (OUT) side where the working oil is discharged from the swing motor 239 are provided.

[0065] The sensor values (hydraulic pressure values) measured by the hydraulic sensors 242 and 244 are output to the controller 10.

[0066] The controller 10 determines the state of the swing bearing based on the hydraulic pressure values measured by at least one of the hydraulic sensors 242 and 244.

[0067] Specifically, the controller 10 includes a wear determination unit 12, an acquisition unit 14, a reporting unit 16, and an analysis unit 18.

[0068] The acquisition unit 14 acquires the hydraulic pressure values measured by at least one of the hydraulic sensors 242 and 244.

[0069] The analysis unit 18 analyzes the hydraulic pressure values acquired by the acquisition unit. In this example, as an example, the analysis unit 18 performs FFT (fast Fourier transform) processing. Thereby, the frequency characteristics of the measured hydraulic pressure values can be obtained.

[0070] The wear determination unit 12 determines the degree of wear based on the frequency characteristics of the hydraulic pressure values analyzed by the analysis unit 18.

[0071] The reporting unit 16 performs a reporting process based on the determination result of the wear determination unit 12.

[0072] Figure 6 It is a flowchart for explaining the abnormality determination of the swing bearing of the controller 10 based on Embodiment 1.

[0073] Refer to Figure 6 , the acquisition unit 14 acquires the data of the hydraulic pressure values from the hydraulic sensors 242 and 244 (step S2).

[0074] The analysis unit 18 analyzes the data of the hydraulic pressure values from the hydraulic sensors 242 and 244 acquired by the acquisition unit 14 (step S3). In this example, as an example, the analysis unit 18 performs FFT processing. Thereby, the frequency characteristics of the hydraulic pressure values can be obtained.

[0075] Next, the wear determination unit 12 compares the frequency characteristics of the hydraulic pressure values analyzed by the analysis unit 18 with the normal data (step S4).

[0076] Next, the wear determination unit 12 determines whether there is an abnormality in the slewing bearing based on the comparison result (step S6).

[0077] In step S6, when the wear determination unit 12 determines that there is no abnormality in the slewing bearing ( "No" in step S6), it returns to step S2 and repeats the above process.

[0078] On the other hand, in step S6, when the wear determination unit 12 determines that there is an abnormality in the slewing bearing ( "Yes" in step S6), it proceeds to step S8, and the wear determination unit 12 notifies the reporting unit 16 of the existence of the abnormality.

[0079] In step S8, the reporting unit 16 performs a reporting process based on the determination result from the wear determination unit 12. As the reporting process, a message urging replacement can be sent, or a lamp urging replacement can be lit. Any means can be used as long as the determination result can be conveyed to the operator.

[0080] Then, the process of abnormality determination ends (end).

[0081] Figure 7 FIG. is a diagram for explaining the change and frequency characteristics of the hydraulic pressure values of the hydraulic sensors 242 and 244 in the slewing bearing during normal operation based on Embodiment 1.

[0082] As an example, the hydraulic pressure on the inlet (IN) side where working oil is supplied to the slewing motor 239 is set as the first motor pressure, and the hydraulic pressure on the outlet (OUT) side where working oil is discharged from the slewing motor 239 is set as the second motor pressure.

[0083] Refer to Figure 7 In (A) of, the upper side is a diagram showing the state of the first motor pressure of the hydraulic sensor 242 provided on the input side of the slewing motor 239.

[0084] The lower side is a diagram showing the state of the second motor pressure of the hydraulic sensor 244 provided on the output side of the slewing motor 239. As shown in this figure, a specified motor pressure is periodically measured alternately on the input side and the output side.

[0085] Refer to Figure 7 In (B) of, the frequency characteristics of the hydraulic sensor 242 provided on the input side of the upper slewing motor 239 with respect to the first motor pressure are shown here. As the frequency characteristics, a state where the first motor pressure is high is detected near the frequency Q, but at other frequencies, the first motor pressure is in a low state.

[0086] In this example, the frequency characteristics of the hydraulic sensor 242 on the input side of the swing motor 239 provided on the upper side with respect to the first motor pressure were described. The frequency characteristics of the second motor pressure of the hydraulic sensor 244 on the output side of the swing motor 239 provided on the lower side are basically the same.

[0087] Figure 8 This is a diagram for explaining the changes and frequency characteristics of the hydraulic values, i.e., the first and second motor pressures, of the hydraulic sensors 242 and 244 in the swing bearing during abnormal conditions based on Embodiment 1.

[0088] Refer to Figure 8 In (A) of, the upper side is a diagram showing the state of the first motor pressure of the hydraulic sensor 242 provided on the input side of the swing motor 239.

[0089] The lower side is a diagram showing the state of the second motor pressure of the hydraulic sensor 244 provided on the output side of the swing motor 239.

[0090] As shown in this diagram, the specified motor pressure is not in a flat state but a substantially constant value, with slight fluctuations. The main reason for this is that deflection (peeling) has occurred in the swing ring 220. For example, the main reason is that at least one of the transfer surfaces of the outer ring 221 and the inner ring 222 has worn due to contact with the rolling elements 241, resulting in deflection (peeling) on the transfer surface.

[0091] Refer to Figure 8 In (B) of, the frequency characteristics of the hydraulic sensor 242 provided on the input side of the swing motor 239 on the upper side with respect to the first motor pressure are shown here. As the frequency characteristics, a state where the first motor pressure is higher is detected at frequencies lower than that near the frequency Q, except near the frequency Q.

[0092] In this example, the frequency characteristics of the hydraulic sensor 242 provided on the input side of the swing motor 239 on the upper side with respect to the first motor pressure were described. The frequency characteristics of the second motor pressure of the lower hydraulic sensor 244 are basically the same.

[0093] Figure 9 This is a diagram for explaining the comparative determination of abnormalities in the swing bearing based on Embodiment 1.

[0094] Figure 9 In (A) of, a diagram schematically showing the frequency characteristics of the first motor pressure supplied to the swing motor 239 of the swing bearing during normal driving is shown.

[0095] Figure 9 In (B) of, a diagram schematically showing the frequency characteristics of the first motor pressure supplied to the swing motor 239 of the swing bearing during abnormal driving is shown.

[0096] The frequency characteristics during abnormal conditions, compared with those during normal conditions, detect a high first motor pressure in a frequency band lower than a specified frequency Q. As an example, a case where the motor pressure p is detected as the high first motor pressure is shown.

[0097] Specifically, the wear determination unit 12 can determine the wear state of the slewing bearing based on whether a first motor pressure higher than a specified threshold pr is detected.

[0098] Based on the method of Embodiment 1, it is possible to analyze the frequency characteristics of the first or second motor pressure supplied to or discharged from the slewing motor 239 to determine the wear state of the slewing bearing.

[0099] The method of directly setting a sensor on the slewing bearing or the like to measure the sensor value of the sensor for determination is easily affected by interference and it is difficult to determine the state with high precision. However, the method based on Embodiment 1 is a method of measuring the motor pressure on the input side or the output side of the slewing motor 239 as a driving device to determine the abnormality of the slewing bearing. Therefore, it is difficult to be affected by interference and the state of the slewing bearing can be determined with high precision.

[0100] (Modification Example of Embodiment 1)

[0101] In the modification example of Embodiment 1, a method of calculating the wear amount of the slewing bearing to determine the state of the slewing bearing will be described.

[0102] Figure 10 An outline block diagram showing the structure of the slewing system of the work machine based on the modification example of Embodiment 1 will be described.

[0103] Refer to Figure 10 , compared with the Figure 5 slewing system of the work machine, the difference is that the controller 10 is changed to the controller 10A. The difference between the controller 10A and the controller 10 is that a wear amount calculation unit 20 is additionally provided.

[0104] The wear amount calculation unit 20 calculates the wear amount of the slewing bearing based on the data of the first and second motor pressures (hydraulic values) of the hydraulic sensors 242 and 244.

[0105] When the wear amount calculation unit 20 detects high first and second motor pressures in a frequency band lower than a specified frequency Q, it calculates the wear amount of the slewing bearing with respect to the first and second motor pressures.

[0106] Figure 11 It is a flowchart for explaining the abnormality determination of the slewing bearing of the controller 10A based on the modification example of Embodiment 1.

[0107] Refer to Figure 11, the acquisition unit 14 acquires data on the hydraulic pressure values from the hydraulic sensors 242 and 244 (step S2).

[0108] The analysis unit 18 analyzes the data on the hydraulic pressure values from the hydraulic sensors 242 and 244 acquired by the acquisition unit 14 (step S3). In this example, as an example, the analysis unit 18 performs FFT processing. Thereby, the frequency characteristics of the hydraulic pressure values can be obtained.

[0109] Next, the wear amount calculation unit calculates the wear amount of the slewing bearing (step S3A).

[0110] Figure 12 It is a diagram for explaining a calculation table showing the relationship between the first motor pressure and the wear amount according to a modification of Embodiment 1.

[0111] Refer to Figure 12 , as this calculation table, it shows a case where the wear amount linearly increases in proportion to the first motor pressure.

[0112] The wear amount calculation unit 20 uses this calculation table and, as an example, calculates the wear amount α for the first motor pressure p.

[0113] Refer to again Figure 11 , the wear determination unit 12 determines whether the wear level has reached a specified value (step S4A).

[0114] Next, the wear determination unit 12 determines whether there is an abnormality in the slewing bearing based on the determination result (step S6A).

[0115] Specifically, it is determined that there is an abnormality in the slewing bearing when the wear amount reaches the specified value. This specified value can be appropriately changed.

[0116] In step S6A, when the wear determination unit 12 determines that there is no abnormality in the slewing bearing (in step S6A, "no"), it returns to step S2 and repeats the above process.

[0117] On the other hand, in step S6A, when the wear determination unit 12 determines that there is an abnormality in the slewing bearing (in step S6A, "yes"), it proceeds to step S8, and the wear determination unit 12 notifies the reporting unit 16 of the existence of the abnormality.

[0118] In step S8, the reporting unit 16 performs a reporting process based on the determination result from the wear determination unit 12.

[0119] Then, the process of abnormality determination ends (end).

[0120] The method according to the modification of Embodiment 1 can analyze the frequency characteristics of the first or second motor pressure supplied to or discharged from the slewing motor 239, calculate the wear amount, and determine the wear state of the slewing bearing.

[0121] The method of directly setting a sensor on a slewing bearing or the like to measure the sensor value of the sensor for determination is easily affected by interference and it is difficult to determine the state with high precision. However, the method according to the modification of Embodiment 1 is a method of measuring the motor pressure on the input side or the output side of the slewing motor 239 as a driving device, calculating the wear amount, and determining an abnormality. The user can set the wear amount to be used as a management value as a threshold value, and can intuitively determine the wear state.

[0122] (Embodiment 2)

[0123] Figure 13 An outline block diagram showing the structure of the slewing system of the work machine according to Embodiment 2 will be described.

[0124] Refer to Figure 13 and Figure 5 Compared with the slewing system of the work machine, the difference is that the controller 10 is changed to the controller 10B. The difference between the controller 10B and the controller 10 is that a wear position estimation unit 22 is additionally provided. A slewing angle detection sensor 246 for detecting the slewing angle of the upper slewing body 230 is also provided. The acquisition unit 14 of the controller 10B acquires the slewing angle data of the upper slewing body 230 together with the data of the hydraulic value.

[0125] The wear position estimation unit 22 estimates the wear position of the slewing bearing based on the data of the first and second motor pressures (hydraulic values) of the hydraulic sensors 242 and 244 at a time point, and the slewing angle data of the slewing angle detection sensor 246 at the time point.

[0126] Figure 14 This is a flowchart for explaining the abnormality determination of the slewing bearing of the controller 10B according to Embodiment 2.

[0127] Refer to Figure 14 The acquisition unit 14 acquires the data of the hydraulic value from the hydraulic sensors 242 and 244 at a time point (step S2A).

[0128] The acquisition unit 14 acquires the slewing angle data of the upper slewing body 230 from the slewing angle detection sensor 246 at a time point (step S2B).

[0129] The analysis unit 18 analyzes the data of the time point acquired by the acquisition unit 14 and the hydraulic pressure values from the hydraulic sensors 242 and 244 (step S3). In this example, as an example, the analysis unit 18 performs FFT processing. Thereby, the frequency characteristics of the hydraulic pressure value can be obtained.

[0130] Next, the wear determination unit 12 compares the frequency characteristics of the hydraulic pressure value analyzed by the analysis unit 18 with the normal data (step S4).

[0131] Next, the wear determination unit 12 determines whether there is an abnormality in the slewing bearing based on the comparison result (step S6).

[0132] In step S6, when the wear determination unit 12 determines that there is no abnormality in the slewing bearing (in step S6, "no"), it returns to step S2 and repeats the above processing.

[0133] On the other hand, in step S6, when the wear determination unit 12 determines that there is an abnormality in the slewing bearing (in step S6, "yes"), it proceeds to step S7.

[0134] In step S7, the wear position estimation unit 22 estimates the position where the slewing bearing is abnormal. Next, the estimated wear position is notified to the reporting unit 16.

[0135] In step S8, the reporting unit 16 performs a reporting process of the existence of an abnormality together with the wear position estimated by the wear position estimation unit 22.

[0136] Then, the process of abnormality determination is ended (end).

[0137] Figure 15 It is a diagram for explaining the motor pressure and slewing angle data that change with the change of the time point based on Embodiment 2.

[0138] Refer to Figure 15 In (A) of, it shows the case where the motor pressures p1, p2, p3, ··· pn are converted with the change of the time points t1 to tn.

[0139] Refer to Figure 15 In (B) of, it shows the case where the slewing angles θ1, θ2, ··· θn change with the change of the time points t1 to tn.

[0140] The wear position can be estimated based on the relationship between the motor pressure and the slewing angle associated with the time point.

[0141] Figure 16 It is a diagram for explaining the estimation of the wear position by the wear position estimation unit 22 based on Embodiment 2.

[0142] Refer toFigure 16 In (A), the change in the first motor pressure (hydraulic value) of the hydraulic sensor 242 is shown. Specifically, when wear occurs in the slewing bearing, there is a change in amplitude compared to the normal state. The wear determination unit 12 determines the wear state of the slewing bearing by detecting a motor pressure higher than a specified threshold pr as described in the first embodiment. Specifically, the wear determination unit 12 determines the section with a large change in amplitude and the wear state of the slewing bearing.

[0143] Refer to Figure 16 In (B), the change in the slewing angle of the upper slewing structure 230 of the construction machine is shown. The wear position estimation unit 22 extracts the slewing angles corresponding to the first time point determined to be in a worn state by the wear determination unit 12 and the last time point determined to be in a worn state.

[0144] As an example, the wear position estimation unit 22 extracts the slewing angle θ1 corresponding to the first time point t1 determined to be in a worn state and the slewing angle θ2 corresponding to the last time point t2 determined to be in a worn state. The range between the slewing angles θ1 - θ2 is the wear range.

[0145] As an example, θ1 (10°) to θ2 (20°) is shown as the wear range.

[0146] Figure 16 The Y-axis in (B) represents the slewing angle (deg). Here, the "slewing angle" refers to the relative slewing angle of the upper slewing structure 230 (outer ring support) with respect to the lower traveling structure 210 (inner ring support).

[0147] Figure 16 In (C), it is a diagram conceptually explaining the wear position of the slewing ring. As an example, the case where the 360° is divided into 8 parts and divided into regions of slewing positions 1 to 8 is shown. Figure 16 The slewing position and the wear range shown in (C) represent the azimuth angle with the front as the reference direction in a state where the fronts of both the lower traveling structure 210 and the working device 232 are aligned (a state where the relative positions of the outer ring and the inner ring are aligned).

[0148] In this example, when a worn state is detected between the slewing angles θ1 - θ2, as Figure 16 shown in (C), at least one of the outer ring and the inner ring at the same azimuth angle position wears when the relative positions of the lower traveling structure 210 and the working device 232 are made to coincide.

[0149] For example, the reporting unit 16 may report the wear range or the slewing position where the wear range is located ("1 (0 - 45deg)") as the estimated wear position. Alternatively, it may be reported by display Figure 16The figure of (C) is used to report the estimated wear position.

[0150] In addition, as described in the modification example of Embodiment 1, a method of calculating the wear amount based on the motor pressure to determine the abnormality of the slewing bearing can also be adopted. In this example, a method of estimating the wear range and wear position using the time point information has been described. However, it is not limited to this, and the wear position can also be estimated by obtaining the motor pressure and slewing angle in association without going through the time point information.

[0151] By the method based on Embodiment 2, the maintenance position can be easily determined by estimating the wear position.

[0152] (Embodiment 3)

[0153] In Embodiment 2, a method of estimating the wear position based on the motor pressure p and the slewing angle θ associated with the time point has been described.

[0154] By accumulating the above data, a data table can be created.

[0155] Figure 17 An outline block diagram showing the structure of the slewing system of the working machine based on Embodiment 3 will be described.

[0156] Refer to Figure 17 , compared with Figure 5 the slewing system of the working machine, the difference is that the controller 10 is changed to the controller 10C. The difference between the controller 10C and the controller 10 is that a wear amount calculation unit 20, a wear position estimation unit 22, and a summarization unit 24 are additionally provided.

[0157] The summarization unit 24 summarizes the data and presents the summarization result.

[0158] Figure 18 is a figure for explaining the data table generated by the summarization unit 24 based on Embodiment 3.

[0159] Refer to Figure 18 , as an example, a case where the 360° is divided into n parts of regions is shown.

[0160] The wear amount and wear range corresponding to each of the regions divided into n regions are shown.

[0161] Specifically, the wear amount is calculated based on the motor pressure when the wear state is detected.

[0162] The wear range can be calculated according to the slewing angles corresponding to the first time point determined to be in the wear state and the last time point determined to be in the wear state.

[0163] As an example, the wear amount "α1" and the wear range "β1" are registered corresponding to the rotation position "1". The wear amount "α2" and the wear range "β2" are registered corresponding to the rotation position "2". The wear amount "α3" and the wear range "β3" are registered corresponding to the rotation position "3".

[0164] The aggregating headquarters 24 constantly confirms whether a wear amount larger than the recorded wear amount is measured within each rotation position as a real-time situation. At the time of measurement, the wear amount corresponding to this position is updated and overwritten.

[0165] The aggregating headquarters 24 can also separately save a data table that is updated and overwritten at regular intervals. As an example, a data table updated and overwritten every 8 hours, every 12 hours, every 20 hours, or every 1 day can also be separately saved.

[0166] In addition, a data table can also be separately saved for each date. For example, the data table updated and overwritten at the time point of 24:00 on January 1st is saved as a data table corresponding to January 1st. Similarly, the data table updated and overwritten at the time point of 24:00 on January 2nd is saved as a data table corresponding to January 2nd. The data table updated and overwritten at the time point of 24:00 on January 3rd is saved as a data table corresponding to January 3rd.

[0167] Figure 19 This is a diagram for explaining the change in the wear amount based on Embodiment 3.

[0168] Refer to Figure 19 , in this example, regarding the data table aggregated by the aggregating headquarters 24, the maximum value of the wear amount for each day is extracted and charted as time-series data. The horizontal axis represents time, and the vertical axis represents the wear level.

[0169] The wear level in this example represents the ratio of the wear amount α to the wear limit αmax.

[0170] Figure 20 This is a diagram for explaining the change in the wear range based on Embodiment 3.

[0171] Refer to Figure 20 , in this example, regarding the data table aggregated by the aggregating headquarters 24, the total value of the wear range for each day is extracted and charted as time-series data. The horizontal axis represents time, and the vertical axis represents the wear level.

[0172] The wear level in this example represents the ratio of the total wear range β to the maximum wear range of 360°.

[0173] Figure 21 This is a diagram for explaining the mapping of the wear position based on Embodiment 3.

[0174] Reference Figure 21 In this example, 360° is divided into 8 parts, and the wear amounts corresponding to the respective rotational positions in the case of dividing into regions of rotational positions 1 to 8 are mapped.

[0175] Regarding the data table summarized by the aggregation unit 24, the wear amounts of the respective rotational positions are extracted and charted. The horizontal axis represents the rotational position, and the vertical axis represents the wear grade.

[0176] The wear grade in this example represents the ratio of the wear amount α to the wear limit αmax.

[0177] Through the mapping of the wear positions, it is possible to easily grasp the wear positions and the wear grades.

[0178] It should be noted that in this example, the case of generating a data table by converting the motor pressure into a wear amount has been described, but it is also possible to use the motor pressure to generate a data table.

[0179] It should be noted that in Figure 19 , the maximum value is extracted from the wear amounts of multiple rotational positions and charted as time-series data, but it is also possible to chart the wear amount of an arbitrarily selected rotational position as time-series data. Or it is also possible to extract the maximum value from arbitrarily selected multiple rotational positions and chart it as time-series data.

[0180] It is also possible to formulate a maintenance plan for the slewing bearing based on the above-described change in the wear amount.

[0181] For example, the controller 10C can also Figure 19 and Figure 20 estimate the period when the slewing bearing becomes abnormal based on the change in the wear grade.

[0182] The controller 10C can also notify the operator of the estimated period as a report process.

[0183] In the above-described embodiment, a hydraulic excavator is listed as an example of a work machine, but it is not limited to a hydraulic excavator, and it can also be applied to other types of work machines equipped with a slewing bearing, such as a crane and a rotary dump truck.

[0184] It should be noted that in this example, the case of obtaining hydraulic value data from both of the hydraulic sensors 242 and 244 has been described, but it is also possible to obtain hydraulic value data from any one of the hydraulic sensors and determine the state of the slewing bearing based on the data of that one hydraulic value. Or, it is also possible to obtain hydraulic value data from both of the hydraulic sensors 242 and 244 and determine the state of the slewing bearing based on the differential data of the hydraulic values.

[0185] In addition, the above-mentioned controller can also adjust the control parameters of the work machine based on the calculated wear amount. Specifically, by feeding back the calculated wear amount to the automatic control system, higher-precision ICT (Information and Communication Technology) construction can be performed. Specifically, the position of the bucket tip can also be corrected based on the calculated wear amount.

[0186] In addition, the above-mentioned controller can also be connected to a network (not shown) and perform data communication processing with an external device (for example, a server).

[0187] At least a part of the functions executed in the controller can also be distributed and executed by a plurality of devices capable of communicating through a network (wide area network and / or local area network). Specifically, at least a part of the various functions executed in the controller can also be executed by the server.

[0188] In addition, when the above-mentioned reporting unit is provided in the server, a message urging replacement can be sent to the information processing device set to be able to communicate with the server, and information related to the replacement time can also be notified.

[0189] In addition, in the above, a method for determining an abnormality of the slewing bearing based on the input / output data (sensing data) of the hydraulic slewing motor as the driving device for driving the slewing bearing has been described, but it is not limited to the hydraulic type. An abnormality of the slewing bearing can also be determined based on the input / output data of an electric slewing motor. Specifically, in the case of an electric slewing motor, current or voltage can also be detected, and an abnormality of the slewing bearing can be determined in the same manner based on the data of the current or voltage.

[0190] In addition, in the above, a method for determining an abnormality of the slewing bearing, i.e., the slewing ring 220, of the hydraulic excavator as the work machine has been described, but it is not limited to the slewing ring 220, and the same can be applied to other mechanisms. For example, the same can be applied to mechanisms such as the gears of a device having a structure of a hydraulic motor and a gearbox and the bearings combined with the gears, and a speed reducer for reducing the rotation of the slewing motor 239.

[0191] In addition, the slewing ring 220 is not limited to Figure 4 the slewing ring shown, and the same can be applied to other slewing rings.

[0192] Figure 22 is a diagram for explaining a slewing ring based on other embodiments.

[0193] Refer to Figure 22, the slewing ring 220A for large construction machinery will be described. The slewing ring 220A has an inner ring 222, an upper outer ring 221A, a lower outer ring 221B, and rollers 241#. The rollers 241# are arranged in three areas. Specifically, the outer ring 221 is separated into an upper outer ring 221A and a lower outer ring 221B.

[0194] The rollers 241# arranged on the upper side are arranged between the inner ring 222 and the upper outer ring 221A so as to be able to roll. The rollers 241# arranged on the side are arranged between the inner ring 222 and the upper outer ring 221A so as to be able to roll. The rollers 241# arranged on the lower side are arranged between the inner ring 222 and the lower outer ring 221B so as to be able to roll.

[0195] The structure of the present application can also be similarly applied to the slewing ring 220A with this structure.

[0196] <Supplementary Note>

[0197] The above-described embodiment includes the following technical ideas.

[0198] <Supplementary Note 1>

[0199] A construction machine, comprising:

[0200] A slewing bearing;

[0201] A drive device (239) that drives the slewing bearing;

[0202] A detection unit (242, 244) that detects the state of at least one of the input to the drive device and the output from the drive device; and

[0203] A determination unit (12) that determines the state of the slewing bearing based on the detection value detected by the detection unit.

[0204] <Supplementary Note 2>

[0205] The construction machine according to Supplementary Note 1, wherein the determination unit determines the state of the slewing bearing based on the comparison result between the detection value and the value in the normal state.

[0206] <Supplementary Note 3>

[0207] The construction machine according to Supplementary Note 1 or 2, wherein the determination unit includes a wear amount calculation unit (20) that calculates the wear amount of the slewing bearing based on the detection value.

[0208] <Supplementary Note 4>

[0209] The work machine according to Note 3, wherein the determination unit further includes a reporting unit (16) that reports when the wear amount is equal to or greater than a threshold value.

[0210] <Supplementary Note 5>

[0211] The work machine according to any one of Supplementary Notes 1 to 4, wherein

[0212] the work machine further includes a rotation angle detection unit (246) that detects a rotation angle,

[0213] the determination unit includes a position estimation unit (22) that estimates the wear position of the slewing bearing based on the rotation angle at the detection time point of the detection value.

[0214] <Supplementary Note 6>

[0215] A control method for a work machine, comprising:

[0216] a step of driving a slewing bearing;

[0217] a step of detecting a state of at least one of an input to a device that drives the slewing bearing and an output from the driving device (S2); and

[0218] a step of determining the state of the slewing bearing based on the detected detection value (S3 to S6).

[0219] <Supplementary Note 7>

[0220] A control system for a work machine, comprising:

[0221] a slewing bearing;

[0222] a driving device (239) that drives the slewing bearing;

[0223] a detection unit (242, 244) that detects a state of at least one of an input to the driving device and an output from the driving device; and

[0224] a determination unit (12) that determines the state of the slewing bearing based on the detection value detected by the detection unit.

[0225] The embodiments of the present disclosure have been described above, but it should be considered that the embodiments disclosed this time are illustrative rather than restrictive in all aspects. The scope of the present disclosure is represented by the claims and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0226] Explanation of reference numerals:

[0227] 10, 10A, 10B Controllers; 12 Wear Determination Unit; 14 Acquisition Unit; 16 Reporting Unit; 18 Analysis Unit; 20 Wear Amount Calculation Unit; 22 Wear Location Estimation Unit; 200 Hydraulic Excavator; 210 Lower Travel Body; 211 Crawler Belt; 220 Slewing Ring; 221 Outer Ring; 222 Inner Ring; 223 Slewing Pinion; 230 Upper Slewing Structure; 231 Cab; 232 Working Equipment; 233 Boom; 234 Arm; 235 Bucket; 236 Engine; 238 Hydraulic Pump; 239 Slewing Motor; 240 Valve; 241 Rolling Element; 242, 244 Hydraulic Sensors.

Claims

1. An operating machine, wherein, the operating machine includes: a slewing bearing; a driving device for driving the slewing bearing; a detection unit for detecting the state of at least one of the input to the driving device and the output from the driving device; and a determination unit for determining the state of the slewing bearing based on the detection value detected by the detection unit.

2. The operating machine according to claim 1, wherein, the determination unit determines the state of the slewing bearing based on the comparison result between the detection value and the value in the normal state.

3. The operating machine according to claim 1, wherein, the determination unit includes a wear amount calculation unit for calculating the wear amount of the slewing bearing based on the detection value.

4. The operating machine according to claim 3, wherein, the determination unit further includes a reporting unit for reporting when the wear amount is equal to or greater than a threshold value.

5. The operating machine according to claim 1, wherein, the operating machine further includes a slewing angle detection unit for detecting the slewing angle, and the determination unit includes a position estimation unit for estimating the wear position of the slewing bearing based on the slewing angle at the detection time point of the detection value.

6. A control method for an operating machine, wherein, the control method for the operating machine includes: a step of driving a slewing bearing; a step of detecting the state of at least one of the input to the device for driving the slewing bearing and the output from the driving device; and a step of determining the state of the slewing bearing based on the detected detection value.

7. A control system for an operating machine, wherein, the control system for the operating machine includes: a slewing bearing; a driving device for driving the slewing bearing; a detection unit for detecting the state of at least one of the input to the driving device and the output from the driving device; and a determination unit for determining the state of the slewing bearing based on the detection value detected by the detection unit.

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