Life evaluation system, life evaluation method, and working machine

Abstract

To provide a life evaluation system and a life evaluation method for accurately evaluating the life of a turning mechanism, and a working machine.SOLUTION: The control unit 41 controls the jib crane 150 so that the jib crane 150 is in a measurement posture during measurement by the measurement unit 21. In this case, the jib crane 150 can be controlled so as to be in a measurement posture that is a posture suitable for evaluating the life when the measurement unit 21 performs measurement. As a result, the measurement unit 21 can accurately measure the jib crane 150 in the measurement posture. The processing unit 42 calculates a determination value based on the accurately measured measurement data, and the determination unit 43 determines whether or not the measurement data is within a predetermined range based on the determination value. Therefore, the lifetime evaluation system 100 can evaluate the lifetime based on accurate measurement data.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a lifespan assessment system, a lifespan assessment method, and a work machine. [Background technology]

[0002] For example, Patent Document 1 discloses a jib crane that includes a tower body, a rotating body installed on the tower body, and a jib attached to the rotating body. This jib crane changes the orientation of the jib by rotating the rotating body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-198630 Summary of the Invention [Problem to be solved by the invention]

[0004] In a work machine having a slewing mechanism such as the jib crane of Patent Document 1, replacing the bearing members of the slewing mechanism is a large-scale and expensive process. Therefore, in long-term operation of the work machine, it is necessary to accurately evaluate the life of the slewing mechanism and determine the timing for replacing the bearing members.

[0005] An object of the present invention is to provide a lifespan assessment system, a lifespan assessment method, and a work machine that accurately assess the lifespan of a swing mechanism. [Means for solving the problem]

[0006] A lifespan assessment system according to one aspect of the present invention is a lifespan assessment system that assesses the lifespan of a rotation mechanism provided in a work machine, and includes a control unit that controls the work machine, a measurement unit that measures the relative position between a first member and a second member that are provided so as to be rotatable relative to each other, a processing unit that processes the measurement data measured by the measurement unit, and a judgment unit that judges whether the judgment value processed by the processing unit is within a predetermined range, and the control unit controls the work machine so that it is in a measurement posture when measurement is performed by the measurement unit.

[0007] In this lifespan assessment system, the measurement unit measures the relative position between a first member and a second member that are rotatable relative to each other. When the relative position between the first member and the second member changes due to wear of the bearing member of the swing mechanism, the measurement unit can measure the change. Here, the control unit controls the working machine so that it assumes a measurement posture during measurement by the measurement unit. In this case, the measurement unit can control the working machine so that it assumes a measurement posture that is suitable for assessing the lifespan when performing measurements. This allows the measurement unit to accurately measure the working machine in the measurement posture. The processing unit calculates a judgment value based on the accurately measured measurement data, and the judgment unit determines whether the judgment value is within a predetermined range. Therefore, the lifespan assessment system can assess the lifespan based on accurate measurement data. As described above, the lifespan of the swing mechanism is accurately assessed.

[0008] The measuring unit may measure the relative position between the first member and the second member in the vertical direction. In this case, the measuring unit can perform measurements on a rotation mechanism whose central axis extends in the vertical direction.

[0009] The work machine may be a jib crane equipped with a jib, and the control unit may control the jib crane so that the jib assumes the minimum radius as the measurement posture. In this case, the center of gravity of the jib crane moves from the jib side to the rotating unit side. Therefore, the control unit can easily make measurements with the measuring unit in a state where a moment is applied from the jib side to the rotating unit side.

[0010] The processing unit may calculate the average value of the measurement data measured by the measuring unit by rotating the rotating body multiple times as the judgment value, and the judgment unit may determine whether the average value is within a predetermined range. In this case, the judgment unit makes the judgment using the average value of the measurement data related to the rotating body multiple times, so that the processing unit can calculate an accurate judgment value.

[0011] The control unit may rotate the rotating body of the rotating mechanism in one direction while the measurement unit continuously measures the relative position during rotation in one direction, and the control unit may rotate the rotating body of the rotating mechanism in the other direction while the measurement unit continuously measures the relative position during rotation in the other direction. In this case, the measurement unit can acquire measurement data relating to rotation in both directions, thereby acquiring measurement data with reduced influence of the direction during rotation.

[0012] The life assessment system may further include a memory unit that stores the measurement data measured by the measurement unit, and the memory unit may store maintenance data obtained by processing the measurement data for each measurement. In this case, the memory unit can store maintenance data that reflects the trends in past measurement data, and the maintenance data can be used to maintain the work machine.

[0013] The life assessment system may further include a notification unit that notifies of an abnormality in the bearing member of the rotation mechanism when the determination unit determines that the determination value exceeds a predetermined range, thereby enabling the bearing member to be replaced promptly when an abnormality occurs in the bearing member.

[0014] The measurement unit may have multiple sensors, and the processing unit may calculate the average value of the measurement data from each sensor as the judgment value. In this case, the measurement unit can obtain measurement data from multiple locations, allowing the processing unit to calculate an accurate judgment value.

[0015] A lifespan assessment method according to one aspect of the present invention is a lifespan assessment method for a rotation mechanism provided in a work machine, and includes a control step for controlling the work machine, a measurement step for measuring the relative position between a first member and a second member that are provided so as to be rotatable relative to each other, a processing step for processing the measurement data measured in the measurement step, and a judgment step for determining whether the judgment value processed in the processing step is within a predetermined range, and the control step controls the work machine so that it is in a measurement posture during measurement in the measurement step.

[0016] A work machine according to one aspect of the present invention includes the above-described life evaluation system.

[0017] According to the lifespan assessment method and the work machine, it is possible to obtain the same effects and advantages as the above-mentioned lifespan assessment system. [Effects of the Invention]

[0018] According to the present invention, it is possible to provide a lifespan assessment system, a lifespan assessment method, and a work machine that accurately assess the lifespan of a swing mechanism. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a schematic diagram showing a life assessment system according to an embodiment of the present invention. [Figure 2] 1 is a schematic configuration diagram of a jib crane in which a life assessment system is incorporated. [Figure 3] FIG. 2 is a schematic cross-sectional view of a part of a turning mechanism. [Figure 4] FIG. [Figure 5] FIG. 2 is a schematic diagram showing an example of a measurement posture of a jib crane. [Figure 6] FIG. 6 is a schematic diagram showing the state of bearings of the rotation mechanism in the measurement posture of FIG. 5(a). [Figure 7] FIG. 6 is a schematic diagram showing the state of the bearings of the rotation mechanism in the measurement posture of FIG. 5(b). [Figure 8] 10 is a graph showing an example of measurement data. [Figure 9]10 is a flowchart showing the processing steps of a lifespan evaluation method performed by the lifespan evaluation system. [Figure 10] 10 is a flowchart showing the processing steps of a lifespan evaluation method performed by the lifespan evaluation system. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, an embodiment of a lifespan assessment system according to the present invention will be described with reference to the accompanying drawings. In the following description, the same or equivalent elements will be designated by the same reference numerals, and redundant description will be omitted.

[0021] First, the installation of a cargo handling apparatus 1 to which an installation guide according to an embodiment of the present invention is applied will be described with reference to Figures 1 and 2. Figure 1 is a schematic diagram showing a lifespan assessment system 100 according to this embodiment. Figure 2 is a schematic configuration diagram of a jib crane in which the lifespan assessment system 100 is incorporated.

[0022] The lifespan assessment system 100 according to this embodiment is a system for assessing the lifespan of a slewing mechanism (also referred to as a slewing support mechanism) provided in a work machine. In this embodiment, a jib crane 150 is exemplified as the work machine. Note that the work machine may be any machine having a slewing mechanism, and in addition to a jib crane, a crane such as a horizontal retractable crane, a hydraulic excavator, an unloader, or the like may also be used. The lifespan assessment system 100 includes, as a system configuration, an information acquisition unit 10, a control device 40, an input unit 51, and an output unit 52 (announcement unit).

[0023] 2, the jib crane 150 is a jib crane that can rotate and travel at the same time. The jib crane 150 has a traveling body 11, a tower body 12, a rotating section 13, a jib 14, a mast 15, and traveling rails R as a device configuration.

[0024] The running body 11 includes a pair of legs 11a, 11b and a girder 11c connecting the pair of legs 11a, 11b at their upper parts. Wheels that are driven on a running rail R are provided on the lower parts of the pair of legs 11a, 11b. The running body 11 runs along the running rail R as the wheels are driven on the running rail R. The tower body 12 is a columnar structure erected on the girder 11c of the running body 11.

[0025] The swivel unit 13 is provided at the upper end of the tower body 12 and is rotatable around a vertical axis CL relative to the tower body 12. A swivel mechanism 17 is provided between the tower body 12 and the swivel unit 13. The swivel unit 13 and the jib 14 rotate around the vertical axis CL via the swivel mechanism 17, with the tower body 12 as the fulcrum. The swivel unit 13 includes a cab 13a at its upper part. The jib 14 is pin-connected to one end 13b of the swivel unit 13. The jib 14 extends from the one end 13b side of the swivel unit 13 as a base end 14a. The mast 15 is erected on the swivel unit 13. The other end 13c of the swivel unit 13, a mast top 15a which is the upper end of the mast 15, and a tip end 14b of the jib 14 are supported by a wire rope W1. As the wire rope W1 is wound up and unwound, the jib 14 raises and lowers with its base end 14a as a fulcrum. The wire rope W2 is connected to the suspending part 16. As the wire rope W2 is wound up and unwound, the suspending part 16 moves up and down. A counterweight 13d, which is a weight for balancing the suspended load, is attached to the other end 13c of the revolving part 13.

[0026] The configuration of the swivel mechanism 17 will now be described with reference to Figure 3. Figure 3 is a schematic cross-sectional view of a portion of the swivel mechanism 17. However, Figure 3 shows the structure and positional relationship of each member of the swivel mechanism 17 in a deformed state. Through holes for bolting each member are omitted from Figure 3. As shown in Figure 3, the swivel mechanism 17 includes a swivel body 30 (first member), a fixed body 31 (second member), and rolling bodies 34A, 34B, and 35. In the following description, the terms "radial direction" and "circumferential direction" refer to directions based on the vertical axis CL (see Figure 2).

[0027] The rotating body 30 is fixed to the rotating section 13 and is a member that rotates together with the rotating section 13 about a vertical axis CL (see FIG. 2). The rotating body 30 is an annular member centered on the vertical axis CL. The rotating body 30 includes an upper support ring 30A and a lower retaining ring 30B. The fixed body 31 is fixed to the tower body 12 and is configured as an immovable member. The fixed body 31 is an annular member centered on the vertical axis CL. The rotating body 30 and the fixed body 31 are provided so as to be rotatable relative to each other. In this embodiment, the fixed body 31 is disposed on the inner peripheral side of the rotating body 30 and is disposed so as to face each other radially. However, the fixed body 31 may also be disposed on the outer peripheral side of the rotating body 30. A ring gear is provided on the inner peripheral surface 31a of the fixed body 31 over the entire circumferential direction. A gear 39 provided on the rotating body 30 engages with the ring gear on the inner peripheral surface 31a (see FIG. 4). When the gear 39 rotates, the gear 39 moves circumferentially along the ring gear. Accordingly, the rotating body 30 rotates around the fixed body 31.

[0028] The fixed body 31 has an annular protrusion 36 that protrudes outward from its outer circumferential surface. The rotating body 30 has a groove 37 on its inner circumferential surface that receives the protrusion 36 of the fixed body 31. A rolling element 34A is accommodated in the space between an upper surface 37a of the groove 37 and an upper surface 36a of the protrusion 36. A rolling element 34B is accommodated in the space between a lower surface 37b of the groove 37 and a lower surface 36b of the protrusion 36. A groove 38 is further formed on the inner circumferential surface of the groove 37 at a position facing the protrusion 36. A rolling element 35 is accommodated in the space between an inner circumferential surface 38a of the groove 38 and an outer circumferential surface 36c of the protrusion 36.

[0029] The rolling elements 34A and 34B are cylindrical rollers arranged with their centerlines extending radially. Therefore, the upper surface 37a serves as a movable raceway 60A for the rolling element 34A, and the upper surface 36a serves as a fixed raceway 60B for the rolling element 34A. The lower surface 37b serves as a movable raceway 61A for the rolling element 34B, and the lower surface 36b serves as a fixed raceway 61B for the rolling element 34B. The rolling element 35 is a cylindrical roller arranged with its centerline extending vertically. Therefore, the inner peripheral surface 38a serves as a movable raceway 62A for the rolling element 35, and the outer peripheral surface 36c serves as a fixed raceway 62B for the rolling element 35. A plurality of the rolling elements 34A, 34B, and 35 are provided around the entire circumference.

[0030] The movable race surfaces 60A, 61A, 62A and the fixed race surfaces 60B, 61B, 62B are rotatable relative to each other. The fixed race surfaces 60B, 61B, 62B are race surfaces whose positions are fixed in an immovable state. The movable race surfaces 60A, 61A, 62A are race surfaces that rotate with the rotation of the rotating unit 30. The rolling elements 34A, 34B, 35 rotate within space in accordance with the rotation of the movable race surfaces 60A, 61A, 62A. Note that in this embodiment, the circumferential positions of the rolling elements 34A, 34B, 35 are not restricted and are in a free state. Therefore, the circumferential positions of the rolling elements 34A, 34B, 35 change with the rotation of the rotating unit 30.

[0031] The sensor 23 of the measuring unit 21 is provided in the revolving mechanism 17. The sensor 23 measures the relative position between the revolving unit 30 and the fixed unit 31, which are rotatable relative to each other. The sensor 23 measures the relative position between the revolving unit 30 and the fixed unit 31 in the vertical direction. In this embodiment, the sensor 23 is fixed to the revolving unit 30 and the revolving unit 13 via a bracket 24. The sensor 23 is disposed so as to face the upper surface 31b of the fixed unit 31 at a distance in the vertical direction. The sensor 23 measures the size of the gap GP between the detection surface (lower surface) and the upper surface 31b. Any sensor capable of measuring the size of the gap GP may be used as the sensor 23. For example, an eddy current sensor, a laser distance sensor, an ultrasonic sensor, or the like may also be used. By measuring the size of the gap GP, the measuring unit 21 can measure the relative position between the revolving unit 30 and the fixed unit 31 in the direction along the vertical axis CL (see FIG. 2).

[0032] The number of sensors 23 and the mounting positions of the sensors 23 in the circumferential direction are not particularly limited. In this embodiment, the configuration shown in FIG. 4 may be employed. FIG. 4 is a top view of the swivel mechanism 17. As shown in FIG. 4, a reference line SL1 and a reference line SL2 perpendicular to the reference line SL1 are set. The reference lines SL1 and SL2 are references in an absolute coordinate system arbitrarily set relative to the location where the jib crane 150 is installed. As an angle around the vertical axis CL, one side of the reference line SL1 is set to 0°. The angle increases counterclockwise from the reference line SL1. At this time, the other side of the reference line SL1 is set to 180°, and the positions of the reference line SL2 are set to 90° and 270°. In the state shown in FIG. 4, the jib 14 extends from the swivel mechanism 17 to one side along the reference line SL1, and the swivel unit 13 is disposed to extend from the swivel mechanism 17 to the other side along the reference line SL1. The swivel mechanism 17 has two sensors 23. In the state shown in FIG. 4, the sensors 23 are provided at the 0° and 180° positions, respectively. However, the sensors 23 may be mounted at positions slightly offset from the 0° and 180° positions. Note that the angle of each sensor 23 in the absolute coordinate system changes as the rotating body 30 rotates. The sensor 23 on the jib 14 side may be referred to as "sensor 23A," and the sensor 23 on the rotating section 13 side may be referred to as "sensor 23B."

[0033] Returning to FIG. 1 , the information acquisition unit 10 includes a measurement unit 21 and a crane status acquisition unit 22. The measurement unit 21 measures the relative position between the rotating body 30 and the fixed body 31, which are provided so as to be rotatable relative to each other, based on the detection results from the above-mentioned sensor 23. The measurement unit 21 measures the relative position in the up-down direction between the rotating body 30 and the fixed body 31. The crane status acquisition unit 22 acquires various information indicating the status of the jib crane 150. The crane status acquisition unit 22 may include, for example, a load meter that measures the load suspended by the jib crane 150, a working radius indicator that detects the working radius of the jib 14 of the jib crane 150, a swing angle detection sensor that detects the swing angle of the jib 14, a traveling position detection sensor that detects the traveling position of the jib crane 150, and a bearing vibration detection sensor that detects bearing vibrations. The information acquisition unit 10 may be installed on board the jib crane 150, or may be installed in a ground office and remotely acquire the detection results of the sensor 23 and various information indicating the status of the jib crane 150.

[0034] The input unit 51 is an interface through which a user inputs information to the control device 40. The input unit 51 may be, for example, a keyboard, a mouse, a touch panel, or a microphone. The output unit 52 is an interface that outputs information from the control device 40 to a user. The output unit 52 may be, for example, a monitor or a speaker. The output unit 52 functions as a notification unit that notifies an operator or manager of an abnormality in the bearing member when it determines that an abnormality has occurred in the bearing member of the slewing mechanism 17 (that is, that the bearing member needs to be replaced). That is, when the determination unit 43 (described later) determines that the determination value exceeds a predetermined range, the output unit 52 notifies the operator or manager of an abnormality in the bearing member of the slewing mechanism 17. Examples of the bearing members of the slewing mechanism 17 that notify of an abnormality include the slewing body 30, the fixed body 31, and the rolling bodies 34A, 34B, and 35. The input unit 51 and the output unit 52 may be provided in the driver's cab of the jib crane 150 or in a management device installed in a ground office. The management device is installed in a ground office or the like, and is a device that manages the jib crane 150. The management device may communicate with the control device 40 wirelessly or via wired communication.

[0035] The control device 40 is a device that controls the entire jib crane 150. The control device 40 includes a processor, memory, storage, a communication interface, and a user interface, and is configured as a general computer. The processor is a computing device such as a CPU (Central Processing Unit). The memory is a storage medium such as a ROM (Read Only Memory) or RAM (Random Access Memory). The storage is a storage medium such as an HDD (Hard Disk Drive). The communication interface is a communication device that realizes data communication. The processor controls the memory, storage, communication interface, and user interface, and realizes the functions described below. The control device 40 realizes various functions, for example, by loading a program stored in the ROM into the RAM and executing the program loaded into the RAM by the CPU. The control device 40 may be composed of multiple computers.

[0036] The control device 40 includes a control unit 41, a processing unit 42, a determination unit 43, and a storage unit 44. These components may be built into the control device 40.

[0037] The control unit 41 controls the jib crane 150. The control unit 41 controls the jib crane 150 so that the jib crane 150 is in the measurement posture during measurement by the measurement unit 21. The control unit 41 controls the jib crane to be in the measurement posture based on the information acquired by the crane state acquisition unit 22. That is, the control unit 41 adjusts the control amount of each parameter for bringing the jib crane 150 into the measurement posture by grasping the state of the jib crane 150 before it was brought into the measurement posture. Furthermore, the control unit 41 determines whether the jib crane 150 is in the measurement posture based on the information acquired by the crane state acquisition unit 22. When measurement starts, the control unit 41 automatically brings the jib crane 150 into the measurement posture.

[0038] Here, the measurement posture is a posture that makes it easier to grasp the wear state of the bearing members of the slewing mechanism 17 based on the size of the gap GP, which is the measurement target of the sensor 23. For example, the measurement posture may be a posture in which the gap GP is larger or smaller than when the jib crane 150 is normally operating due to the influence of the wear state of the bearing members. Specific examples of the measurement posture will be described with reference to FIGS. 5 to 7. FIG. 5 is a schematic diagram showing an example of the measurement posture of the jib crane 150. FIG. 6 is a schematic diagram showing the state of the bearings of the slewing mechanism 17 in the measurement posture of FIG. 5(a). FIG. 7 is a schematic diagram showing the state of the bearings of the slewing mechanism 17 in the measurement posture of FIG. 5(b). Note that in FIGS. 6 and 7, the gaps between each rolling element and the lane surface are exaggerated to make the characteristics of the measurement postures easier to understand.

[0039] As shown in FIG. 5(a), the control unit 41 controls the jib crane 150 so that the jib 14 assumes the minimum radius as the measurement posture. In this case, the control unit 41 retracts the jib 14 to its maximum height. At this time, the hoisting unit 16 of the jib crane 150 is not suspending any load. As a result, a moment M1 is generated on the swivel mechanism 17 from the jib 14 toward the swivel unit 13 due to the weight of the swivel unit 13 and counterweight 13d. This moment M1 is greater than the moment generated during normal operation from the jib 14 toward the swivel unit 13. In this situation, the swivel unit 30 on the swivel unit 13 side moves downward, and the movable raceway surface 60A, which rotates while being pressed against the upper rolling element 34A, becomes a wear surface prone to wear. The size of the gap GP2 detected by the sensor 23B on the swivel unit 13 side is smaller than that during normal operation. The size of the gap GP2 reflects the wear state of the movable race surface 60A, which is a wear surface, and the wear state of the rolling elements 34A. The greater the wear of the movable race surface 60A and the rolling elements 34A, the smaller the gap GP2. On the jib 14 side, as the rotating unit 30 moves upward, the movable race surface 61A, which rotates while being pressed against the lower rolling elements 34B, becomes the wear surface that is most susceptible to wear. The size of the gap GP1 detected by the sensor 23A on the jib 14 side at this time becomes larger than during normal operation. The size of the gap GP1 reflects the wear state of the movable race surface 61A, which is a wear surface, and the wear state of the rolling elements 34B. The greater the wear of the movable race surface 61A and the rolling elements 34B, the larger the gap GP1.

[0040] As shown in FIG. 5(b), the control unit 41 controls the jib crane 150 so that the jib 14 assumes the maximum radius as the measurement posture. In this case, the control unit 41 tilts the jib 14 to its minimum height. At this time, a load is suspended from the hoisting unit 16 of the jib crane 150. As a result, the weight of the load at the position farthest from the vertical axis CL generates a moment M2 on the swivel mechanism 17, acting from the swivel unit 13 toward the jib 14. This moment M2 is greater than the moment acting from the swivel unit 13 toward the jib 14 during normal operation. In this situation, the swivel unit 30 on the jib 14 side moves downward, and the movable raceway surface 60A, which rotates while being pressed against the upper rolling element 34A, becomes a wear surface prone to wear. The size of the gap GP1 detected by the sensor 23A on the jib 14 side is smaller than that during normal operation. The size of the gap GP1 reflects the wear state of the movable race surface 60A, which is a wear surface, and the wear state of the rolling elements 34A. The greater the wear of the movable race surface 60A and the rolling elements 34A, the smaller the gap GP1. On the swivel unit 13 side, the swivel unit 30 moves upward, and the movable race surface 61A, which rotates while being pressed against the lower rolling elements 34B, becomes the wear surface that is most susceptible to wear. The size of the gap GP2 detected by the sensor 23B on the swivel unit 13 side at this time is larger than during normal operation. The size of the gap GP2 reflects the wear state of the movable race surface 61A, which is a wear surface, and the wear state of the rolling elements 34B. The greater the wear of the movable race surface 61A and the rolling elements 34B, the larger the gap GP1.

[0041] Returning to FIG. 1 , the processing unit 42 processes the measurement data measured by the measurement unit 21. The processing unit 42 may process the measurement data in any manner as long as a judgment value based on the measurement data is obtained that can be used to make a judgment in the judgment unit 43. The processing unit 42 calculates the judgment value by performing statistical processing on the obtained measurement data. The judgment unit 43 determines whether the judgment value processed by the processing unit 42 is within a predetermined range. If the judgment value is within the range, it can be determined that it is time to replace the bearing member of the rotation mechanism 17. The judgment unit 43 sets a predetermined threshold for the judgment value and determines whether the judgment value is equal to or greater than the threshold or whether the judgment value is equal to or less than the threshold. The threshold is set to a value that can determine whether the wear of the member requires replacement. For example, the judgment unit 43 determines that the member needs to be replaced if the judgment value based on the size of the gap GP2 in FIG. 6 and the gap GP1 in FIG. 7 is equal to or less than the predetermined threshold. The judgment unit 43 determines that the member needs to be replaced if the judgment value based on the size of the gap GP1 in FIG. 6 and the gap GP2 in FIG. 7 is equal to or greater than the predetermined threshold.

[0042] An example of the processing performed by the processing unit 42 will now be described. For example, the control unit 41 rotates the rotating body 30 of the rotating mechanism 17 in one direction, and the measurement unit 21 continuously measures the relative position (size of the gap GP) between the rotating body 30 and the fixed body 31 while rotating in the one direction. The control unit 41 also rotates the rotating body 30 of the rotating mechanism 17 in the other direction, and the measurement unit 21 continuously measures the relative position (size of the gap GP) between the rotating body 30 and the fixed body 31 while rotating in the other direction. The processing unit 42 calculates, as a determination value, the average value of the measurement data measured by the measurement unit 21 during multiple revolutions of the rotating body 30. The determination unit 43 determines whether the average value is within a predetermined range. The measurement unit 21 also has multiple sensors 23. In this case, the processing unit 42 calculates, as a determination value, the average value of the measurement data from each sensor 23.

[0043] For example, when the rotating unit 30 rotates once, one sensor 23 obtains measurement data GC as shown in FIG. 8 . The measurement data GC indicates an example of the magnitude of the gap GP acquired by the sensor 23 at each angular position. When the rotating unit 30 rotates multiple times, measurement data GC is obtained for each revolution. When the rotating unit 30 rotates in the opposite direction, measurement data GC for the opposite revolution is obtained. The processing unit 42 calculates the average value of the multiple measurement data GC for each angular position. The processing unit 42 also calculates the average value of the magnitude of the gap GP for all angular positions of the measurement data GC related to the average value as the judgment value. Note that the method of calculating the judgment value by the processing unit 42 is not limited to the above-described method. For example, the processing unit 42 may extract angular positions at which characteristics indicative of wear are present from the measurement data GC in FIG. 8 and calculate the average value of the extracted values.

[0044] The memory unit 44 stores the measurement data measured by the measurement unit 21. The memory unit 44 may store maintenance data obtained by processing the measurement data for each measurement. For example, when a graph of the measurement data GC shown in FIG. 8 is obtained by measuring at a certain timing, the memory unit 44 stores the graph. When a graph of new measurement data is obtained at the next measurement timing, the memory unit 44 writes and stores the graph of the new measurement data so that it is overlaid on the graph of the existing measurement data GC. Each time a graph of new measurement data is obtained, the memory unit 44 writes and stores the graph so that it is overlaid on the existing graph. The memory unit 44 may exist on a cloud server and store the measurement data on the cloud server, or may be provided in a management device at the ground office.

[0045] Next, a lifespan assessment method will be described with reference to FIGS. 9 and 10. FIGS. 9 and 10 are flowcharts illustrating the processing of the lifespan assessment method performed by the lifespan assessment system 100. The processing of FIGS. 9 and 10 is executed by each component of the lifespan assessment system 100 at a predetermined timing. However, the processing of the lifespan assessment method is not limited to that shown in FIGS. 9 and 10. As shown in FIG. 9, in the cab, the operator turns on a switch to place the jib crane 150 in the measurement posture. This causes the control unit 41 to control the jib crane 150 to be in the measurement posture (step S10). Next, the operator turns on a measurement mode right rotation switch. This causes the control unit 41 to rotate the jib 14 to the right at a low speed notch, and the measurement unit 21 starts measurement using the sensor 23 (step S20). The control unit 41 stops the rotation when the jib 14 has rotated 360° (0°) to the right, and the measurement unit 21 ends the measurement (step S30). The processes of steps S20 to S30 may be performed multiple times.

[0046] Next, the operator turns on the measurement mode left turn switch. As a result, the control unit 41 rotates the jib 14 left at a low speed notch, and the measurement unit 21 starts measurement using the sensor 23 (step S40). When the jib 14 has rotated 360° (0°) left, the control unit 41 stops the rotation, and the measurement unit 21 ends the measurement (step S50). Note that the processing of steps S40 to S50 may be performed multiple times.

[0047] Next, the operator turns on the result output switch. This causes the processing unit 42 to calculate the average value of the measurement data obtained from multiple right turns and the measurement data obtained from multiple left turns as a judgment value (step S60). Next, the judgment unit 43 determines whether the judgment value is within a predetermined range (step S70). If it is determined in step S70 that the measurement data is within the range, the output unit 52 outputs the measurement data (step S100). On the other hand, if it is determined in step S70 that the measurement data is outside the range, the output unit 52 outputs an alarm to the operator (step S80). The output unit 52 also notifies the operator that a bearing member of the turning mechanism 17 needs to be replaced (step S90). The output unit 52 also outputs the measurement data when the notification was made (step S100). This completes the processing shown in FIGS. 9 and 10.

[0048] Next, the functions and effects of the lifespan assessment system 100 and lifespan assessment method according to this embodiment will be described.

[0049] In this lifespan assessment system 100, the measurement unit 21 measures the relative position between the rotating body 30 and the fixed body 31, which are rotatable relative to each other. When the relative position between the rotating body 30 and the fixed body 31 changes due to wear of the bearing members of the swing mechanism 17, the measurement unit 21 can measure the change. Here, the control unit 41 controls the jib crane 150 so that the jib crane 150 is in a measurement posture during measurement by the measurement unit 21. In this case, the measurement unit 21 can control the jib crane 150 so that the measurement posture is suitable for assessing the lifespan. This allows the measurement unit 21 to accurately measure the jib crane 150 in the measurement posture. The processing unit 42 calculates a judgment value based on the accurately measured measurement data, and the judgment unit 43 determines whether the judgment value is within a predetermined range based on the judgment value. Therefore, the lifespan assessment system 100 can assess the lifespan based on accurate measurement data. As described above, the lifespan of the swing mechanism 17 is accurately assessed.

[0050] The measuring unit 21 may measure the relative position in the vertical direction between the rotating body 30 and the fixed body 31. In this case, the measuring unit 21 can perform measurements on the rotating mechanism 17 whose central axis extends in the vertical direction.

[0051] In the case of the jib crane 150, the swivel mechanism 17 is installed at a high altitude, making it difficult to access for measurement. The lifespan of the swivel mechanism 17 can be evaluated based on the wear between the raceway surface and the rolling elements over long-term use, but the change in the gap is very small and is therefore affected by the crane's posture and the skill of the person performing the measurement. In the lifespan assessment system 100 according to this embodiment, the jib crane 150 is positioned for measurement, thereby increasing the reproducibility of measurement conditions and enabling accurate assessment regardless of the skill of the person performing the measurement. Furthermore, the lifespan assessment system enables accurate assessment through sensor-based measurement and control, thereby preventing excessively frequent replacement. Therefore, the number of times access to high places for replacement can be reduced.

[0052] The work machine is a jib crane 150 equipped with a jib 14, and the control unit 41 may control the jib crane 150 so that the jib 14 assumes a posture in which the radius of the jib 14 is minimum as the measurement posture. In this case, the center of gravity of the jib crane 150 moves from the jib 14 side to the swivel unit 13 side. Therefore, the control unit 41 allows the measuring unit 21 to easily perform measurements in a state in which a moment M1 is applied from the jib 14 side to the swivel unit 13 side.

[0053] The processing unit 42 may calculate the average value of the measurement data measured by the measuring unit 21 through multiple revolutions of the revolving unit 30 as a judgment value, and the judgment unit 43 may judge whether the average value is within a predetermined range. In this case, the judgment unit 43 makes a judgment using the average value of the measurement data related to multiple revolutions, thereby enabling the processing unit 42 to calculate an accurate judgment value.

[0054] The control unit 41 may rotate the rotating body 30 of the rotating mechanism 17 in one direction while the measurement unit 21 continuously measures the relative position during the rotation in one direction, and the control unit 41 may rotate the rotating body 30 of the rotating mechanism 17 in the other direction while the measurement unit 21 continuously measures the relative position during the rotation in the other direction. In this case, the measurement unit 21 can acquire measurement data relating to the rotation in both directions, thereby acquiring measurement data in which the influence of the direction during the rotation is reduced.

[0055] The lifespan assessment system 100 further includes a memory unit 44 that stores the measurement data measured by the measuring unit 21, and the memory unit 44 may store maintenance data obtained by processing the measurement data for each measurement. In this case, the memory unit 44 can store maintenance data that reflects the trends in past measurement data, and the maintenance data can be used for maintaining the jib crane 150.

[0056] The lifespan assessment system 100 may further include an output unit 52 (notification unit) that notifies of an abnormality in the bearing member of the turning mechanism 17 when the determination unit 43 determines that the determination value exceeds a predetermined range. This makes it possible to quickly replace the bearing member at the timing when an abnormality in the bearing member occurs.

[0057] The measurement unit 21 may have a plurality of sensors 23, and the processing unit 42 may calculate the judgment value as the average value of the measurement data of each sensor 23. In this case, the measurement unit 21 can acquire measurement data at a plurality of locations, allowing the processing unit 42 to calculate an accurate judgment value.

[0058] The lifespan assessment method according to this embodiment is a lifespan assessment method for a swivel mechanism provided in a work machine, and includes a control step for controlling the work machine, a measurement step for measuring the relative position between a swivel body 30 and a fixed body 31 that are provided so as to be rotatable relative to each other, a processing step for processing the measurement data measured in the measurement step, and a judgment step for judging whether the judgment value processed in the processing step is within a predetermined range, and the control step controls the work machine so that it is in a measurement posture during measurement in the measurement step.

[0059] The work machine according to this embodiment is equipped with the life evaluation system 100 described above.

[0060] According to the lifespan assessment method and the work machine, it is possible to obtain the same functions and effects as those of the lifespan assessment system 100 described above.

[0061] The present invention is not limited to the above-described embodiments.

[0062] In the above embodiment, the sensor is provided on the rotating body side, but the sensor may also be provided on the fixed body side.

[0063] By providing a vibrometer on the bearing body, the health of the rolling elements can be evaluated, and the signs and life limit can be evaluated together. Furthermore, the life assessment system 100 can be used to monitor the life from a remote location. [Explanation of symbols]

[0064] 21...measuring unit, 30...rotating body (first member), 31...fixed body (second member), 41...control unit, 42...processing unit, 43...determination unit, 44...memory unit, 52...output unit (alarm unit), 100...lifespan evaluation system, 150...jib crane (working machine).

Claims

1. A life evaluation system for evaluating the life of a swing mechanism provided in a work machine, a control unit that controls the work machine; a measuring unit that measures a relative position between a first member and a second member that are provided so as to be rotatable relative to each other; a processing unit that processes measurement data measured by the measurement unit; a determination unit that determines whether the determination value processed by the processing unit is within a predetermined range, The control unit controls the work machine so that the work machine is in a measurement posture when the measurement unit takes measurement.

2. The life assessment system according to claim 1 , wherein the measurement unit measures a relative position between the first member and the second member in a vertical direction.

3. The work machine is a jib crane equipped with a jib, The life assessment system according to claim 1 , wherein the control unit controls the jib crane so that the measurement posture is a posture in which the jib has a minimum radius.

4. the processing unit calculates an average value of the measurement data measured by the measurement unit through a plurality of revolutions of the rotating body as the determination value, The lifespan assessment system according to claim 1 , wherein the determining unit determines whether the average value is within the predetermined range.

5. the control unit rotates a rotating body of the rotating mechanism in one direction, and the measurement unit continuously measures the relative position during the rotation in the one direction; 5. The life assessment system according to claim 4, wherein the control unit rotates a rotating body of the rotating mechanism in the other direction, and the measurement unit continuously measures the relative position during the rotation in the other direction.

6. further comprising a storage unit that stores the measurement data measured by the measurement unit, The lifespan assessment system according to claim 4 , wherein the storage unit stores maintenance data obtained by processing the measurement data for each measurement.

7. The life assessment system according to claim 4 , further comprising a notification unit that notifies an abnormality when the determination unit determines that the determination value exceeds the predetermined range.

8. the measurement unit has a plurality of sensors, The life evaluation system according to claim 4 , wherein the processing unit calculates an average value of the measurement data of each sensor as the determination value.

9. A method for evaluating a lifespan of a swing mechanism provided in a work machine, comprising: a control step of controlling the work machine; a measuring step of measuring a relative position between a first member and a second member that are rotatably provided relative to each other; a processing step of processing measurement data measured in the measuring step; a determination step of determining whether or not the determination value processed in the processing step is within a predetermined range, In the control step, the work machine is controlled so that the work machine is in a measurement posture during measurement in the measurement step.

10. A work machine equipped with the life evaluation system according to claim 1.

Images