hydraulic excavator

Abstract

To provide a hydraulic excavator capable of accurately estimating the wear condition of idlers and rollers of a crawler-type traveling device without being affected by the condition of the ground on which work is performed.SOLUTION: When a test start button 44 is operated, jack-up determining means 43b instructs to jack up either a left or right track type traveling device 3 by a display 46. When the jack-up is performed and a ready button 45 is operated, a crawler track 3e on the side separated from the ground is driven by the jack-up. Based on the detection by a master pin sensor 27 and a rotation amount sensor 28, a wear amount estimating unit 43a measures a rotation amount N of an idler 3b or carrier roller 3c when the crawler track 3e is driven by a measurement section (10 revolutions), and compares the rotation amount N with each determination value Nlimit, Ntrouble, and Ntension to determine the usage limit of the idler 3b and the carrier roller 3c, the presence or absence of a failure, and the necessity of adjusting the tension of the crawler track 3e.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a hydraulic excavator. [Background technology]

[0002] This type of hydraulic excavator is equipped with track-type traveling devices on both the left and right sides of a lower traveling body designed for traveling on unleveled terrain, etc., and a front work station equipped with a bucket, etc., and a driver's cab, etc. are mounted on an upper rotating body that is rotatably connected to the lower traveling body. For example, the track-type traveling device is formed by an endless track wound around a drive sprocket, an idler, and a plurality of rollers. When the left and right drive sprockets are rotated by a traveling hydraulic motor provided on the lower traveling body, the left and right tracks are driven independently while being guided by the idler and each roller, and the hydraulic excavator travels straight or steers depending on the drive direction and drive speed of the left and right tracks.

[0003] During operation of a track-type traveling device, the outer surfaces of the idlers and rollers come into contact with the track and gradually wear away. Although a highly wear-resistant hardened layer is formed on the outer surfaces through surface treatment, if the hardened layer disappears due to wear, the track cannot be guided normally, so the idlers and rollers must be replaced before they reach their service limit. As a technology for determining such replacement times, for example, Patent Document 1 discloses a track inspection device for bulldozers that estimates the amount of wear on the idlers and rollers of the track-type traveling device. This track inspection device detects the rotational speeds of the drive sprocket, idlers, and rollers while the bulldozer is traveling, and estimates the amount of wear on each of the idlers and rollers based on the rotational speed of the drive sprocket. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Patent No. 9,371,630 Summary of the Invention [Problem to be solved by the invention]

[0005] However, because this type of construction machine operates on uneven ground, the idlers and rollers are subject to influences from the ground, such as soil, gravel, mud, and the like, or the effects of uneven ground. For example, if soil or the like gets caught between the track and the idlers or rollers, smooth rotation cannot be expected. In such cases, the rotational speed of the idlers or rollers cannot be accurately detected, resulting in errors in estimating the amount of wear and, ultimately, in determining when they should be replaced.

[0006] The present invention has been made to solve these problems, and an object of the present invention is to provide a hydraulic excavator that can accurately estimate the wear state of the idlers and rollers of the track-type traveling device, regardless of the condition of the ground on which work is carried out. [Means for solving the problem]

[0007] In order to achieve the above object, the hydraulic excavator of the present invention is a hydraulic excavator in which a track-type traveling unit is provided on each of the left and right sides of a lower traveling body, each of which has an endless track wound around a drive sprocket and a plurality of driven rollers, and an articulated front working unit is provided by rotatably connecting an upper rotating body to the lower traveling body, and the hydraulic excavator is equipped with a control device in which at least one of the left and right track-type traveling units is an inspection object, the control device having: a wear amount estimation unit that drives the track-type traveling unit to be inspected and estimates the amount of wear of the driven rollers; and a jack-up determination unit that determines a jack-up state in which the front working unit is brought into contact with the ground and the track-type traveling unit to be inspected is separated from the ground, and the wear amount estimation unit estimates the amount of wear of the driven rollers when the jack-up determination unit determines that the track-type traveling unit to be inspected is in a jack-up state. [Effects of the Invention]

[0008] According to the hydraulic excavator of the present invention, the wear state of the idlers and rollers of the crawler-type traveling device can be accurately estimated without being affected by the condition of the ground on which work is carried out. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a side view showing a hydraulic excavator according to a first embodiment. [Figure 2] FIG. 2 is a partial detailed view of the left side frame of the hydraulic excavator with the side wall removed. [Figure 3] FIG. 3 is a plan view corresponding to FIG. 2. [Figure 4] FIG. 10 is a characteristic diagram showing the relationship between the rotation amount of the idler and carrier roller and the operating time when the crawler belt is driven only for a measurement section. [Figure 5] 3 is a cross-sectional view taken along line VV in FIG. 2, showing a sensor housing portion provided in the yoke. [Figure 6] 3 is a detailed view of part A in FIG. 2, showing a sensor fixing bracket provided on a side frame. [Figure 7] FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. 6, showing the sensor fixing bracket. [Figure 8] FIG. 2 is a control block diagram showing the functions of a controller. [Figure 9] 4 is a flowchart showing a crawler inspection routine executed by a controller of the first embodiment. [Figure 10] 10 is a flowchart illustrating a track inspection routine executed by the controller. [Figure 11] 10 is a flowchart showing a tension / failure determination value update routine executed by the controller. [Figure 12] FIG. 10 is an explanatory diagram showing the hydraulic excavator with the left track-type traveling device jacked up. [Figure 13] 10 is a diagram showing a control map for calculating a correction coefficient Kn from an adjuster protrusion amount L. FIG. [Figure 14] FIG. 10 is a partial detailed view of the hydraulic excavator according to the second embodiment, with a side wall removed from the left side frame. [Figure 15] FIG. 15 is a plan view corresponding to FIG. [Figure 16] 16 is a cross-sectional view taken along line XVI-XVI in FIG. 14, showing the rotation amount sensor built into the yoke. [Figure 17] 15 is a detailed view of part B in FIG. 14 showing a rotation amount sensor built into the side frame. [Figure 18] 18 is a cross-sectional view taken along line XVIII-XVIII in FIG. 17, showing the rotation amount sensor. [Figure 19] 10 is a flowchart showing a crawler inspection routine executed by a controller of a second embodiment. [Figure 20] 10 is a flowchart showing a track inspection routine executed by the controller. DETAILED DESCRIPTION OF THE INVENTION

[0010] [First embodiment] A first embodiment of a hydraulic excavator embodying the present invention will now be described. 1 is a side view showing a hydraulic excavator according to this embodiment, and first, a schematic configuration of the hydraulic excavator will be described based on this drawing. In the following description, the front-rear, left-right, and up-down directions are expressed from the perspective of an operator riding on the hydraulic excavator.

[0011] A track-type traveling device 3 is provided on each of the left and right sides of the undercarriage 2 of the hydraulic excavator 1. The track-type traveling device 3 is configured by wrapping an endless track 3e, which is made up of a number of connected track plates, around a drive sprocket 3a, an idler 3b (corresponding to the "driven roller" of the present invention), a carrier roller 3c (corresponding to the "driven roller" of the present invention), and a track roller 3d. When the left and right drive sprockets 3a are rotated by a hydraulic traveling motor (not shown) provided on the undercarriage 2, the left and right tracks 3e are guided independently in the circumferential direction by the idler 3b and each of the rollers 3c, 3d, and the hydraulic excavator 1 travels straight or steers according to the drive direction and drive speed of the left and right tracks 3e.

[0012] An upper rotating body 4 is mounted on the lower traveling body 2 via a rotating device 2a, and the upper rotating body 4 is driven to rotate by a hydraulic rotating motor (not shown) of the rotating device 2a. A multi-articulated front work unit 5 is mounted in front of the upper rotating body 4, and the front work unit 5 is made up of a boom 6, an arm 7, and a bucket 8. The angle of the boom 6 is changed by a boom cylinder 6a, the angle of the arm 7 is changed by an arm cylinder 7a, and the angle of the bucket 8 is changed by a bucket cylinder 8a.

[0013] An operator's cab 10 where an operator sits is provided at the front on a frame 9 of the upper rotating body 4, and a fuel tank 11, a machinery room 12, a counterweight 13, etc. are provided behind the operator's cab 10 on the frame 9. Although not shown, an engine is mounted in the machinery room 12, and the hydraulic motor for traveling or swinging and each of the hydraulic cylinders 6a to 8a are operated by the supply of hydraulic oil from a hydraulic pump driven by the engine.

[0014] Fig. 2 is a partial detailed view of Fig. 1 with the side wall removed from the left side frame, and Fig. 3 is a plan view corresponding to Fig. 2. Note that the following description will focus on the track adjustment device 15 that adjusts the tension of the track 3e of the left track-type traveling device 3, but the right side has the same symmetrical structure.

[0015] As shown in FIG. 3, the track frame 16 constituting the lower running body 2 is formed by connecting side frames 18 to both the left and right sides of a center frame 17, and these side frames 18 support the drive sprocket 3a, idler 3b, carrier roller 3c, and track roller 3d.

[0016] 2 and 3, the side frame 18 has a rectangular cylindrical shape extending in the front-rear direction, and is closed at its front and rear ends by a front wall 18a and a rear wall (not shown). The base ends of a pair of left and right guide rails 19 are fixed to the front wall 18a, and an idler 3b is disposed between each of the guide rails 19. A guide groove 20 extending in the front-rear direction is formed between a pair of upper and lower rail members 19a, 19b that constitute each guide rail 19. A pair of left and right tip portions 21a of a yoke 21 that is Y-shaped in plan view are disposed in each guide groove 20 so as to be slidable in the front-rear direction, and the left and right ends of a shaft 22 of the idler 3b are rotatably supported by each tip portion 21a.

[0017] A base end 21b of the yoke 21 extending rearward protrudes into the side frame 18 through a communication hole 18b in the front wall 18a and is connected to the track adjustment device 15. As shown in FIG. 1, the guide rail 19 is concealed by a side wall 18c, and the track adjustment device 15 is concealed by a side wall 18d.

[0018] The configuration of the track adjuster 15 is well known, as seen in, for example, Japanese Patent Application Laid-Open Publication No. 2020-152334, and therefore only a brief description will be provided. The track adjuster 15 is configured to bias the yoke 21 in a protruding direction (to the left in FIG. 2) using a compression spring (not shown), and to maintain the position of the yoke 21 against this biasing force using an adjuster cylinder. When the rod 23 (shown in FIG. 2) expands or contracts in response to the supply or discharge of grease to the adjuster cylinder, the yoke 21, biased by the compression spring, displaces in the fore-and-aft direction, thereby adjusting the fore-and-aft position of the idler 3b and, ultimately, the tension of the track 3e. The fore-and-aft position of the adjuster cylinder's rod 23 (hereinafter referred to as the adjuster extension amount L, which corresponds to the "track adjuster actuation amount" in this specification) is detected by a stroke sensor 24 (corresponding to the "actuation amount detection unit" in this specification). This adjuster extension amount L is a value correlated with the length of the track 3e, which gradually expands with operation.

[0019] During operation of the track-type traveling device 3, the outer peripheral surfaces of the idler 3b and rollers 3c, 3d come into contact with the crawler 3e and gradually wear away, making it necessary to replace the idler 3b and rollers 3c, 3d before they reach their service limits. Patent Document 1, for example, describes a technique for estimating the wear on the idler 3b and rollers 3c, 3d, in which the rotational speeds of the drive sprocket, idler, and rollers are detected while the bulldozer is traveling, and the wear on the idler and rollers is estimated based on the relative rotational speeds. However, because construction machinery works on uneven ground, the accurate rotational speeds of the idler and rollers cannot be detected due to the influence of the ground, resulting in errors in the wear estimation.

[0020] In view of these problems, the present inventors have focused on jacking up, an operation unique to hydraulic excavators 1. The technology of Patent Document 1 involves actually running a bulldozer, and therefore cannot avoid the influence of the ground. In contrast, the hydraulic excavator 1 can use the front work unit 5 to set the track-type traveling unit 3 in a jacked-up state (hereinafter simply referred to as jacking up the track-type traveling unit 3) away from the ground, and therefore can create a pseudo-traveling state (an operating state of the track-type traveling unit 3) without being affected by the ground.

[0021] Based on the above findings, in the hydraulic excavator 1 of this embodiment, the tracked traveling unit 3 is jacked up to estimate the amount of wear on the idler 3b and rollers 3c, 3d. Additionally, in this embodiment, the state of the tracked traveling unit 3 is inspected based on the estimated amount of wear (the amount of rotation N, which will be described later and corresponds to the "rotational state" of the present invention), and a series of inspection processes is executed to suggest maintenance work (parts replacement, adjustment of the tension of the track 3e, repair, etc.) that is currently required for the tracked traveling unit 3 based on the inspection results. For this processing, the hydraulic excavator 1 is provided with a track inspection device 26, the details of which will be described below.

[0022] FIG. 4 is a characteristic diagram showing the relationship between the rotation amount N of the idler 3b and the carrier roller 3c and the operating time when the crawler belt 3e is driven only through the measurement section. FIG. 5 is a cross-sectional view taken along line VV in FIG. 2, showing the sensor housing portion provided in the yoke 21. FIG. 6 is a detailed view of portion A in FIG. 2, showing the sensor fixing bracket provided on the side frame 18. FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. 6, showing the same sensor fixing bracket.

[0023] First, an outline of the wear amount estimation process will be described. In this embodiment, the wear amounts of the idler 3b and the front and rear carrier rollers 3c are estimated. The estimation principle is based on the finding that a correlation exists between the amount of rotation N of the idler 3b and the carrier roller 3c when the crawler 3e is driven over a predetermined section (hereinafter referred to as the measurement section) and the amount of wear of each. When the crawler 3e is driven by the drive sprocket 3a, the outer peripheral surfaces of the idler 3b and the carrier roller 3c move circumferentially in accordance with the measurement section of the crawler 3e, and the amount of rotation N in the measurement section is determined by the amount of circumferential movement. When the idler 3b and the carrier roller 3c reduce in diameter due to wear, the amount of rotation N gradually increases accordingly. Therefore, as shown in FIG. 4, a correlation exists between the amount of rotation N and the amount of wear.

[0024] Therefore, the rotation amount N of the idler 3b and carrier roller 3c when the crawler belt 3e is driven for only the measurement section is measured. Then, by comparing this rotation amount N with a replacement determination value Nlimit that is preset as the usage limit of the idler 3b or carrier roller 3c (point d in the figure), it becomes possible to determine whether or not each needs to be replaced.

[0025] For this reason, the left and right tracked traveling units 3 are each provided with a master pin sensor 27 (corresponding to the "measurement section detection unit" of the present invention) for detecting the measurement section of the track 3e, and a rotation amount sensor 28 (corresponding to the "rotation state detection unit" of the present invention) for detecting the amount of rotation N. In the following explanation, the mounting state of the sensors 27, 28 on the left tracked traveling unit 3 will be described, but the right side has the same symmetrical structure.

[0026] 2 and 3, master pin sensor 27 is equipped with a light-emitting unit and a light-receiving unit (not shown), and is configured as a so-called photoelectric sensor that detects an object by reflecting light. Master pin sensor 27 is fixed to the outer peripheral surface of swing device 2a, its light-emitting direction is set to the left, and its vertical position coincides with the upper tension point of crawler belt 3e. Although not shown, crawler belt 3e is made up of multiple connected track plates, and a master pin 29 that can be attached and detached for maintenance of crawler belt 3e is used at one connection point. A reflector 30 is affixed to the inner end of master pin 29, and every time reflector 30 reaches a position to the left of master pin sensor 27 as crawler belt 3e moves, reflector 30 is detected by master pin sensor 27. In other words, every time crawler belt 3e makes one revolution, master pin sensor 27 detects reflector 30.

[0027] The rotation amount sensor 28 is detachable from the body of the hydraulic excavator 1, and is shared (i.e., a single sensor is used) between the idler 3b and the front and rear carrier rollers 3c. For this reason, sensor fixing parts 31 and 32 (each corresponding to the "fixing part" of the present invention) to which the rotation amount sensor 28 can be attached are provided at positions close to the idler 3b and the carrier roller 3c, respectively.

[0028] The sensor fixing portion 31 of the idler 3b is provided on the yoke 21. As shown in FIG. 5, a sensor housing 33 is recessed from the left side of the left end 21a of the yoke 21. The rotation amount sensor 28 is disposed within the sensor housing 33 and can be fixed with screws (not shown). The rotation amount sensor 28 is also configured as a photoelectric sensor. When the rotation amount sensor 28 is fixed within the sensor housing 33, its light-emitting and light-receiving portions (not shown) face the left side surface of the idler 3b through a communication hole 33a in the sensor housing 33. A reflector 34 is attached to an eccentric position on the left side surface of the idler 3b. As the idler 3b rotates, the reflector 34 is detected by the rotation amount sensor 28 every time it reaches a position to the right of the rotation amount sensor 28—in other words, every time the idler 3b rotates once. Note that the master pin sensor 27 and the rotation amount sensor 28 are not limited to these and can be replaced with sensors based on any detection principle.

[0029] The sensor fixing portions 32 of the front and rear carrier rollers 3c are respectively provided on the upper surface 18e of the side frame 18. The sensor fixing portion 32 of the front carrier roller 3c will be described below with reference to Figures 6 and 7, but the sensor fixing portion 32 of the rear carrier roller 3c has the same structure.

[0030] First, regarding the carrier roller 3c, a roller support portion 36 is fastened with bolts 37 to a base 35 welded to the upper surface 18e of the side frame 18, and the carrier roller 3c is rotatably supported in a cantilevered manner via a shaft 38 on the left side of the roller support portion 36. A through hole 18f is formed in the upper surface 18e, and soil and sand scraped off the crawler belt 3e by contact with the carrier roller 3c are discharged downward through the through hole 18f.

[0031] A base end 39a of a bracket 39 is fastened to the top surface 18e of the side frame 18 with a bolt 40 at a position to the left of the carrier roller 3c, and a tip end 39b is bent at a right angle from the base end 39a and stands upright on the side frame 18. A rotation amount sensor 28 can be fixed to the left side surface of the tip end 39b with a screw (not shown), and when fixed to the bracket 39, the light-emitting unit and the light-receiving unit of the rotation amount sensor 28 face the left end surface of the carrier roller 3c via a communication hole 39c formed through the tip end 39b. A reflector 41 is affixed to an eccentric position on the left end surface of the carrier roller 3c, and the reflector 41 is detected by the rotation amount sensor 28 every time the reflector 41 reaches a position to the right of the rotation amount sensor 28 as the carrier roller 3c rotates, in other words, every time the carrier roller 3c rotates once.

[0032] During normal operation when wear amount estimation is not being performed, rotation amount sensor 28 is detached from both sensor mounting portions 31, 32, and its reflectors 34, 41 and reflector 30 of master pin sensor 27 are also detached. Because dust and the like is generated particularly near the ground while hydraulic excavator 1 is in operation, the purpose of this is to prevent malfunction of rotation amount sensor 28 and contamination of reflectors 30, 34, 41. In this embodiment, master pin sensor 27, which is located in a position that is less susceptible to the effects of dust, is fixed, but sensor 27, like rotation amount sensor 28, may also be detachable and attached only when necessary.

[0033] 8 is a control block diagram showing the functions of the controller 43 (control device). The controller 43 comprises a storage device (ROM, RAM, etc.) that has a built-in control program, a central processing unit (CPU), a timer counter, etc. The input side of the controller 43 is connected to the stroke sensor 24, the master pin sensor 27, and the rotation amount sensor 28, as well as to an inspection start button 44, a preparation complete button 45, and left and right tension adjustment complete buttons 47L, 47R. The output side of the controller 43 is also connected to a display 46 (corresponding to the "display unit" of the present invention) that can be viewed by an operator.

[0034] The buttons 44, 45, 47L, 47R and the display 46 are installed in the operator's cab 10 of the hydraulic excavator 1. The inspection start button 44 is operated to instruct the start of a series of inspection processes, and the preparation complete button 45 is operated when preparatory work such as jacking up prior to the inspection processes is completed. In addition, the left and right tension adjustment complete buttons 47L, 47R are operated when tension adjustment of the left or right track 3e is completed. The display 46 functions to provide the operator with guidance on the preparatory work prior to the inspection processes and to display the inspection results.

[0035] Normally, the rotation amount sensor 28 is stored in a designated storage location with its wiring disconnected from the controller 43, and when it is fixed to the sensor fixing parts 31, 32 of the vehicle body to perform an inspection, it is simultaneously connected to the controller 43. The controller 43 includes a wear amount estimation unit 43a, a jack-up determination unit 43b, a use limit determination unit 43c, a tension adjustment determination unit 43d, a failure determination unit 43e, a failure determination value update unit 43f, and a tension determination value update unit 43g.

[0036] The wear amount estimating unit 43a measures the rotation amount N of the idler 3b and the carrier roller 3c in the measurement section of the crawler 3e as the wear amount of each. The jack-up determining unit 43b determines the jack-up state of the left and right crawler-type traveling devices 3.

[0037] The service limit determination unit 43c determines whether the idler 3b or the carrier roller 3c has reached its service limit. The tension adjustment determination unit 43d determines whether tension adjustment of the crawler belt 3e is necessary. The malfunction determination unit 43e determines whether or not there is a malfunction in the idler 3b or the carrier roller 3c. The fault determination value update unit 43f updates the fault determination value Ntrouble that is applied to the determination process of the fault determination unit 43e. The tension determination value update unit 43g updates the tension determination value Ntension that is applied to the determination process of the tension adjustment determination unit 43d.

[0038] 9 and 10 are flowcharts showing a track inspection routine executed by the controller 43, and the controller 43 executes this routine at predetermined control intervals while the hydraulic excavator 1 is in operation. For the sake of convenience, it is assumed below that the track adjustment device 15 is in a state immediately after manufacture, the idler 3b and the front and rear carrier rollers 3c are brand new, and the tension of the track 3e is adjusted to a specified value. When the hydraulic excavator 1 starts operating, as shown in Fig. 4, the amount of rotation N of the idler 3b and carrier roller 3c in the measurement section of the track 3e gradually increases from Ninitial, which corresponds to the initial value, as wear progresses.

[0039] In the inspection process, the track-type traveling device 3 is inspected based on the rotation amount N, and necessary maintenance work is determined based on the inspection results. In order to perform this process, the values ​​of the following requirements 1) to 4) are set in advance, as shown in Figure 4.

[0040] 1) A replacement determination value Nlimit corresponding to the rotation amount N when the idler 3b and the carrier roller 3c reach their usage limit. Since the outer diameters of the idler 3b and carrier roller 3c when worn down to their service limits requiring replacement are known, a rotation amount Nlimit corresponding to the measurement section of the crawler belt 3e is set in advance based on each outer diameter. For example, the replacement determination value Nlimit for each of the idler 3b and carrier roller 3c is set to a value of about +30% of each initial value Ninitial.

[0041] 2) An increase ΔN1 corresponding to the increase in the rotation amount N from the time when the tension adjustment of the track 3e is performed until the time when the next tension adjustment is required. Slack in the track 3e due to stretching occurs due to various factors, such as wear of the pins connecting the track shoes, but as the slack in the track 3e progresses, wear of the idler 3b and the carrier roller 3c also progresses. Therefore, an increase in the rotation amount N correlates with the progression of slack in the track 3e, and the rotation amount N can be used as an index for determining whether or not tension adjustment of the track 3e is necessary. Therefore, in this embodiment, the rotation amount N of the idler 3b is used as an index, and the relationship between the rotation amount N and the slack in the track 3e is derived based on a test performed in advance using an actual vehicle, and then an increase ΔN1 in the idler rotation amount N until tension adjustment is required is preset. Of course, the need for tension adjustment may also be determined based on the rotation amount N of the carrier roller 3c instead of the idler 3b.

[0042] 3) Amount of decrease ΔN2 in the rotation amount N that occurs when the idler 3b or the carrier roller 3c fails. The breakdown may be, for example, a lack of oil in the bearing or the intrusion of foreign matter, and either of these causes will manifest as a decrease in rotation. Therefore, in order to determine when the rotation amount N, which should increase as wear progresses, has decreased, a decrease amount ΔN2 is set in advance. Of course, since the wear progression characteristics differ between the idler 3b and the carrier roller 3c, the replacement determination value Nlimit and the decrease amount ΔN2 are set individually for each.

[0043] 4) Measurement section (10 laps) of the track 3e when measuring the rotation amount N. In this embodiment, the minimum rotation amount N that the rotation amount sensor 28 can detect is one revolution, so the rotation amount N measured in the measurement section may contain an error equivalent to up to one revolution. Therefore, by setting the measurement section to a sufficiently long length of 10 revolutions, the influence of the error is suppressed, enabling accurate measurement of the rotation amount N and, ultimately, accurate estimation of the amount of wear. However, the measurement section is not limited to this and can be changed as desired. Furthermore, to increase the resolution of the rotation amount sensor 28, for example, instead of the reflector 34, markers may be provided protruding from the idler 3b or the carrier roller 3c at 10° intervals and detected by the rotation amount sensor 28. In this case, the desired detection accuracy of the rotation amount N can be ensured even if the measurement section is further shortened.

[0044] Meanwhile, the inspection process is carried out in the order of left side and right side, and with the corresponding track-type traveling device 3 jacked up, the idler 3b, front carrier roller 3c, and rear carrier roller 3c are inspected in that order. The inspection process involves measuring the amount of rotation N, determining whether or not there is a malfunction based on that value, and further determining whether or not the usage limit has been reached. In addition, when inspecting the idler 3b, it is also determined whether or not tension adjustment of the track 3e is necessary.

[0045] 9 and 10, the controller 43 determines in step S1 whether the inspection start button 44 has been operated, and if the determination is No (negative), the routine is temporarily terminated. The operator of the hydraulic excavator 1 operates the inspection start button 44 at any interval (for example, once a month) and checks whether maintenance is required for the track-type traveling device 3 based on the information displayed on the display 46. If the determination in step S1 is Yes (affirmative), in step S2, the display 46 is used to provide guidance on preparatory work that should be performed prior to the inspection process, and in the subsequent step S3, it is determined whether the preparation complete button 45 has been operated (jack-up determination unit 43b).

[0046] The guidance sequentially displays on the display 46 the details of the work to jack up either the left or right tracked traveling device 3, the work to attach the rotation amount sensor 28 to the sensor fixing parts 31 and 32, the work to connect the wiring of the rotation amount sensor 28 to the controller 43, the work to attach the reflectors 30, 34, and 41 to the master pin 29 of the track 3e, the idler 3b, and each carrier roller 3c, etc. The first guidance for inspecting the left tracked traveling device 3 instructs the operator to jack up the left tracked traveling device 3, instructs the operator to fix the rotation amount sensor 28 to the sensor fixing part 31 of the idler 3b, and further instructs the operator to attach each of the reflectors 30, 34, and 41.

[0047] Based on this guidance, the hydraulic excavator 1 keeps the left tracked traveling unit 3 in a jacked-up position with the bucket 8 of the front work unit 5 on the ground, as shown in FIG. 12. When all of the guided preparation work is completed, the operator operates the preparation complete button 45. If the determination in step S3 is Yes, the left tracked traveling unit 3 is driven in step S4, and the amount of rotation N of the idler 3b in the measurement section is measured in the following step S5 (wear amount estimation unit 43a). For example, the start point of the measurement section is determined to be the time when the master pin sensor 27 first detects the reflector 34 after starting to drive the tracked traveling unit 3, and the end point of the measurement section is determined to be the time when the reflector 34 is detected for the 11th time. As a result, the tracked traveling unit 3 makes 10 revolutions during the measurement section, and the number of times the rotation amount sensor 28 detects the reflector 41 during that time is measured and used as the amount of rotation N of the idler 3b.

[0048] At this time, although the left track-type traveling unit 3 of the hydraulic excavator 1 is jacked up, the track 3e is driven by the drive sprocket 3a in the same way as during normal traveling, and the idler 3b and carrier roller 3c rotate accordingly. Furthermore, because the track 3e is separated from the ground by the jacking up, a phenomenon such as soil and sand on the ground becoming caught between the track 3e and the idler 3b or carrier roller 3c is prevented. Therefore, the idler 3b and carrier roller 3c rotate in response to the drive of the track 3e without being affected by the ground.

[0049] In step S6, the adjuster protrusion amount L detected by the stroke sensor 24 is read, and in the following step S7, a correction coefficient Kn is calculated from the adjuster protrusion amount L based on the control map in FIG. 12. When the track 3e stretches during operation, the measurement section becomes longer, the rotation amount N increases, and the correlation with the amount of wear is lost. Although the situation remains the same even if the tension of the track 3e is adjusted, the adjuster protrusion amount L at this time correlates with the length of the track 3e and, therefore, the measurement section. Therefore, the purpose of the correction coefficient Kn is to correct the rotation amount N to compensate for the effect of the stretching of the track 3e.

[0050] For example, as shown in Fig. 13, the correction coefficient Kn is set to 1 when the adjuster projection amount L is at the time of manufacture of the track adjuster device 15, and the correction coefficient Kn is set to a value less than 1 in response to an increase (+) in the adjuster projection amount L, and the correction coefficient Kn is set to a value less than 1 in response to a decrease (-) in the adjuster projection amount L. Note that a decrease in the adjuster projection amount L occurs when one track plate is removed to shorten the extended track 3e, but even if the number of track plates is reduced, the correlation between the adjuster projection amount L and the length of the track 3e shown in Fig. 12 does not change. In the following step S8, such a correction coefficient Kn is multiplied by the rotation amount N. As a result, the rotation amount N is corrected to a value that is not affected by the length of the track 3e.

[0051] From step S9 onwards, each inspection process is carried out based on the rotation amount N of the idler 3b. To facilitate understanding, the process contents will be explained in order from the time of manufacture to the limit of use, following the progression of operating time (amount of wear) shown in Figure 4. When the hydraulic excavator 1 after manufacture begins operation, the rotation amount N of the idler 3b in the measurement section of the track 3e gradually increases from the initial value Ninitial as wear progresses, as shown in Figure 4. The rotation amount Ninitial is known from the outer diameter of the idler 3b and the measurement section of the track 3e immediately after manufacture. Therefore, based on the rotation amount Ninitial, at the time of manufacture, a tension determination value Ntension (=Ninitial+ΔN1) for determining whether or not tension adjustment of the track 3e is necessary, and a fault determination value Ntrouble (=Ntrouble-ΔN2) for determining whether or not a fault exists in the idler 3b are set. Note that at the time of manufacture, a fault determination value Ntrouble for the carrier roller 3c is also set.

[0052] The controller 43 determines in step S9 whether the rotation amount N is equal to or greater than the replacement determination value Nlimit (use limit determination unit 43c), and determines in step S10 whether the rotation amount N is equal to or less than the malfunction determination value Ntrouble (fault determination unit 43e).If it determines in step S11 that the idler 3b is being inspected, the controller 43 determines in step S12 whether the rotation amount N is equal to or greater than the tension determination value Ntension (tension adjustment determination unit 43d).

[0053] For example, in the case of point a on the idler characteristic line N shown in Fig. 4, the determinations in steps S9 and S10 are No, and the process returns to step S12 via step S10, proceeding to step S13. In step S13, a message indicating that the left tracked traveling device 3 is normal is displayed on the display 46, and then the process proceeds to step S14. Therefore, based on the display 46, the operator at this time recognizes that the idler 3 is not broken down and has not reached its service limit, and also recognizes that adjustment of the tension of the track 3e is not necessary.

[0054] 4, if tension adjustment of the track 3e is required, a "Yes" determination is made in step S12 and the process proceeds to step S15. In step S15, a message indicating that tension adjustment of the left track 3e should be performed is displayed on the display 46, and the process proceeds to step S14. Therefore, the operator at this time recognizes that tension adjustment of the left track 3e is required based on the display 46, and performs the adjustment. This tension adjustment work may be performed at another opportunity after all inspection processes have been completed, or may be performed using this opportunity since the left track 3e is currently in a jacked-up state.

[0055] In either case, once the slack in the crawler belt 3e has been eliminated and the work is complete, the operator operates the tension adjustment completion button 47L on the left side. Based on this operation, the tension determination value Ntension and the trouble determination value Ntrouble are updated by the routine in Figure 11 (the same applies to the carrier roller 3c), the details of which will be described later.

[0056] Furthermore, if a failure occurs in the idler 3b, the amount of rotation N deviates from the idler characteristic line N in the direction of decreasing rotation, as shown by point c in Figure 4. For this reason, a Yes determination is made in step S10 and the process proceeds to step S16. In step S16, a message indicating that a failure has occurred in the left idler 3b and that repair is required is displayed on the display 46, and the process proceeds to step S14. Therefore, the operator at this time recognizes the failure of the left idler 3b based on the indication on the display 46 and performs appropriate repairs, such as greasing the bearings.

[0057] Furthermore, when the idler 3b reaches its service limit as indicated by point d on the idler characteristic line N in Fig. 4, a "Yes" determination is made in step S9 and the process proceeds to step S17. In step S17, a message indicating that the left idler 3b has reached its service limit and requires replacement is displayed on the display 46, and the process proceeds to step S14. Therefore, the operator at this time recognizes that the left idler 3b needs to be replaced based on the indication on the display 46 and carries out the replacement.

[0058] Meanwhile, after displaying the display 46 in any of steps S13, 15 to 17 as described above, in step S14 it is determined whether or not inspection processing for the idler 3b and the front and rear carrier rollers 3c has all been completed. Since inspection processing for only the idler 3b has been completed so far, a "No" determination is made and the process returns to step S2. In step S2, guidance is given to remove the rotation amount sensor 28 from the sensor mounting portion 31 of the idler 3b and mount it on the sensor mounting portion 32 of the front carrier roller 3c. At this point in time, the left track-type traveling unit 3 is maintained in a jacked-up state following the previous inspection processing for the idler 3b.

[0059] The subsequent processing from steps S3 to S17 is basically the same as that for the idler 3b. In steps S3 to S8, the amount of rotation of the front carrier roller 3c is measured, and in steps S9 and S10, the amount of rotation N is compared with a replacement determination value Nlimit and a malfunction determination value Ntrouble set for the carrier roller 3c. For example, in the case of point a on the carrier roller characteristic line N shown in Figure 4, the operator recognizes that the track-type traveling device 3 is normal based on the normal message in step S13.

[0060] Furthermore, if the deviation from the carrier roller characteristic line N occurs as at point c in Fig. 4, the carrier roller 3c is repaired based on the repair message in step S16. Furthermore, if the deviation occurs at point d on the carrier roller characteristic line N in Fig. 4, the carrier roller 3c is replaced based on the replacement message in step S17. Note that since the inspection target is the carrier roller 3c, a "No" determination is made in step S11, and the processes in steps S12 and S15 are not executed.

[0061] Thereafter, the process proceeds to step S2 via step S14, where inspection processing is performed on the rear carrier roller 3c, but the details are the same as those for the front carrier roller 3c, so a description thereof will be omitted. Then, when the process proceeds to step S14 again, in response to the completion of all inspection processing for the left side, a Yes determination is made and the process proceeds to step S18. In step S18, it is determined whether inspection processing for both the left and right track-type traveling devices 3 has been completed, and because the right side has not yet been inspected, a No determination is made and the process returns to step S2.

[0062] In step S2, as the first guidance for inspecting the right-side tracked traveling unit 3, an instruction is given to jack up the right-side tracked traveling unit 3 instead of the left-side tracked traveling unit 3, and an instruction is given to fix the rotation amount sensor 28 to the sensor fixing portion 31 of the idler 3b. The processing from step S3 to step S17 onwards is the same as that for the left-side idler 3b, and then a No determination is made in step S14 to perform inspection processing for the front carrier roller 3c, and then inspection processing for the rear carrier roller 3c is performed. The processing for these carrier rollers 3c is also the same as for the left side.

[0063] When the inspection processes for both the left and right sides are completed and a Yes determination is made in step S18, the process proceeds to step S19, where guidance is given on the finishing work to end the inspection process, and then the routine ends. In detail, the work content to stop jacking up the right tracked traveling device 3, the work content to remove the rotation amount sensor 28 from the sensor fixing portion 32 of the rear carrier roller 3c, the work content to disconnect the wiring of the rotation amount sensor 28 from the controller 43, the work content to remove the reflectors 30, 34, 41, etc. are sequentially displayed on the display 46. The operator carries out the finishing work as instructed, and the hydraulic excavator 1 is prepared to start operation.

[0064] In this embodiment, the rotation amount N of the track rollers 3d is not measured, and the replacement work is carried out at the same time using the service limit of the carrier rollers 3c as a guide, but the present invention is not limited to this. For example, a sensor fixing portion 32 may be provided in the vicinity of each track roller 3d, and a rotation amount sensor 28 may be fixed to each sensor fixing portion 32 in turn during the inspection process, and the presence or absence of a malfunction in each track roller 3d and the need for replacement may be determined based on the measured rotation amount N.

[0065] On the other hand, when the tension of either the left or right track 3e is adjusted based on the tension adjustment message in step S15 as described above, the operator operates the tension adjustment completion button 47L, 47R on that side. While the hydraulic excavator 1 is in operation, the controller executes a tension / failure determination value update routine shown in Fig. 11 at predetermined control intervals. In step S21 of this routine, it is determined whether the left tension adjustment completion button 47L has been operated, and in step S22 it is determined whether the right tension adjustment completion button 47R has been operated. If a "No" determination is made in either process, the routine is temporarily terminated.

[0066] If the determination in step S21 is Yes, then in step S23, the tension determination value Ntension of the left crawler 3e is updated by adding the increase amount ΔN1 (Ninitial+ΔN1) (tension determination value update unit 43g), and in step S24, the failure determination value Ntrouble of each of the left idler 3b and carrier roller 3c is updated by subtracting the decrease amount ΔN2 (Ntrouble-ΔN2) (failure determination value update unit 43f). Also, if the determination in step S22 is Yes, then in steps S25 and S26, the right tension determination value Ntension and the failure determination value Ntrouble are updated with the same content as in steps S23 and S24 (tension determination value update unit 43g, failure determination value update unit 43f). Of course, if the tension of both the left and right crawler tracks 3e has been adjusted, both the left and right tension determination values ​​Ntension and the failure determination values ​​Ntrouble are updated.

[0067] As described above, according to this embodiment, either the left or right tracked traveling device 3 is jacked up and driven, and the rotation amount N of the idler 3b and carrier roller 3c in the measurement section of the track 3e is measured. Based on this rotation amount N, an inspection process is performed to determine the service limit or malfunction of the idler 3b or carrier roller 3c, and whether or not tension adjustment of the track 3e is required. Since the tracked traveling device 3 is thus placed in a pseudo-traveling state by jacking up, it is possible to prevent the rotation of the idler 3b or carrier roller 3c from being affected by the ground. Therefore, it is possible to accurately measure the rotation amount N, which correlates with the current amount of wear of the idler 3b and each carrier roller 3c, and accurate inspection results can be obtained based on this rotation amount N.

[0068] For example, with regard to the service limits of the idler 3b and the carrier roller 3c, the amount of rotation N of each is regarded as the amount of wear, and when the amount of rotation N reaches or exceeds the replacement judgment value Nlimit, a message on the display 46 prompts replacement. Because the replacement time for the idler 3b or the carrier roller 3c can be accurately determined based on the accurate amount of rotation N, it is possible to prevent, for example, a situation in which the hydraulic excavator 1 becomes unable to travel due to a delayed replacement, or a situation in which the operating costs of the hydraulic excavator 1 rise due to an excessively early replacement.

[0069] Furthermore, failures of the idler 3b or the carrier roller 3c can also be accurately determined based on the accurate rotation amount N. More specifically, because a failure is determined at an early stage when the rotation amount N has decreased slightly, appropriate repairs can be carried out early, thereby preventing the hydraulic excavator 1 from becoming unable to travel.

[0070] Furthermore, whether or not tension adjustment of the tracks 3e is necessary can be accurately determined based on the accurate amount of rotation N, allowing tension adjustment to be performed at the appropriate time. For example, if adjustment work is delayed, it may cause problems with the operation of the hydraulic excavator 1, and conversely, if adjustment work is performed too early, it may cause operating costs to rise, but these situations can be prevented in advance.

[0071] In addition, each time the tension of either the left or right crawler 3e is adjusted, the tension determination value Ntension and the failure determination value Ntrouble for the side whose tension has been adjusted are updated by the tension / failure determination value update routine of Fig. 11. Therefore, thereafter, it is determined in step S12 based on the updated tension determination value Ntension whether or not the tension of the crawler 3e needs to be adjusted, and it is determined in step S10 based on the updated failure determination value Ntrouble whether or not there is a failure in the idler 3b and the carrier roller 3c.

[0072] The tension determination value Ntension is a value updated based on the increment ΔN1 using the amount of rotation N at the time the tension of the track 3e was adjusted as a reference, and the increment ΔN1 is a value set as the increase in the amount of rotation N from the time the tension of the track 3e is adjusted until the next tension adjustment becomes necessary. Therefore, it is possible to accurately determine whether the next tension adjustment is necessary based on the updated tension determination value Ntension, and ultimately to perform tension adjustment at an appropriate timing that is neither too much nor too little.

[0073] In step S10, the failure determination value Ntrouble functions as a threshold value for determining whether the rotation of the idler 3b or the carrier roller 3c has decreased. Since the failure determination value Ntrouble is updated to an appropriate value each time the tension of the crawler belt 3e is adjusted, the failure can be accurately determined and prompt repair can be performed.

[0074] Furthermore, in this embodiment, the rotation amount sensor 28 is fixed to the sensor fixing portion 31 near the idler 3b or the sensor fixing portion 32 near the carrier roller 3c only when it is necessary to perform an inspection process for the track-type traveling device 3, and the reflectors 30, 34, and 41 are affixed to their respective predetermined locations. Because dust and other particles are generated, particularly near the ground, during operation of the hydraulic excavator 1, the sensor fixing portions 31 and 32 and the locations where the reflectors 30, 34, and 41 are attached are exposed to the dust and other particles. This can cause malfunction of the rotation amount sensor 28 and soiling of the reflectors 30, 34, and 41, but these problems can be prevented by removing the rotation amount sensor 28 and the reflectors 30, 34, and 41 during operation of the hydraulic excavator 1. As a result, the measurement section corresponding to the drive of the track 3e can be accurately detected, and the rotation amount N of the idler 3b and the carrier roller 3c in the measurement section can also be accurately measured, thereby enabling accurate inspection based on the rotation amount N.

[0075] On the other hand, in this embodiment, the rotation amount N of the idler 3b and carrier roller 3c is measured when the crawler 3e is driven only through the measurement section, and this rotation amount N is used as an index to determine the service limit and presence or absence of a malfunction of the idler 3b and carrier roller 3c, as well as the need for tension adjustment of the crawler 3e. The rotation amount N of the idler 3b and carrier roller 3c is determined according to the measurement section of the crawler 3e, and as the diameter decreases due to wear, the rotation amount N gradually increases accordingly. Furthermore, if the rotation of the idler 3b or carrier roller 3c is hindered due to lack of oil, or if some kind of malfunction occurs, the rotation amount N decreases accordingly. Because each inspection process is performed using this rotation amount N as an index, each situation can be accurately determined, thereby improving inspection accuracy.

[0076] In particular, in this embodiment, a correction coefficient Kn is calculated from the adjuster protrusion amount L, which correlates with the length of the crawler belt 3e, based on the control map in Fig. 13, and the measured rotation amount N is corrected using the correction coefficient Kn. This makes it possible to compensate for the effect of stretching of the crawler belt 3e, and to obtain a more accurate rotation amount N, and therefore more accurate inspection results.

[0077] [Second embodiment] Next, a second embodiment of a hydraulic excavator 1 embodying the present invention will be described. The difference from the first embodiment is that the rotation amount sensor 28 is built into the body of the hydraulic excavator 1 and is exposed to the outside only when it is necessary to perform an inspection process, but the other configuration is the same as that of the first embodiment. Therefore, the same component numbers are used for common configuration parts and their explanations will be omitted, and the explanation will focus on the differences.

[0078] FIG. 14 is a partial detailed view of the left side frame 18 of the hydraulic excavator 1 of this embodiment with the side walls 18c and 18d removed, FIG. 15 is a plan view corresponding to FIG. 14, and FIG. 16 is a cross-sectional view taken along line XVI-XVI in FIG. 14 showing the rotation amount sensor 28 built into the yoke 21.

[0079] The rotation amount sensors 28 of this embodiment are provided individually for the idler 3b and the front and rear carrier rollers 3c, which are the detection targets, and are built into the vehicle body in proximity to the detection targets. First, the rotation amount sensor 28 for the idler 3b will be described. The rotation amount sensor 28 is built into the yoke 21 that supports the idler 3b. A sensor housing portion 51 (corresponding to the "housing portion" of the present invention) is formed in the left tip portion 21a of the yoke 21, and the sensor housing portion 51 opens to the right through a communication hole 51a. The rotation amount sensor 28 and a drive unit 52 are disposed within the sensor housing portion 51. The rotation amount sensor 28 is configured as a photoelectric sensor, as in the first embodiment, and its light-emitting portion and light-receiving portion correspond to the communication hole 51a.

[0080] A shielding plate 53 is disposed in the communication hole 51a and is connected to the drive unit 52 via an interlocking arm 54. Drive of the drive unit 52 causes the shielding plate 53 to slide between a closed position indicated by a solid line and an open position indicated by a two-dot chain line. When the shielding plate 53 is in the closed position, the communication hole 51a is closed, isolating the sensor housing 51 from the outside and preventing the intrusion of dust and the like. When the shielding plate 53 is in the open position, the communication hole 51a is open, exposing the rotation amount sensor 28 to the outside through the communication hole 51a, with its light-emitting portion and light-receiving portion facing the left side surface of the idler 3b and enabling it to detect the reflector 34.

[0081] 17 is a detailed view of part B in FIG. 14 showing the rotation amount sensor 28 built into the side frame 18, and FIG. 18 is a cross-sectional view of the same rotation amount sensor 28 taken along line XVIII-XVIII in FIG. The rotation amount sensors 28 for the front and rear carrier rollers 3c are respectively built into the side frames 18. The rotation amount sensor 28 for the front carrier roller 3c will be described below with reference to Figures 17 and 18, but the rotation amount sensor 28 for the rear carrier roller 3c has the same structure.

[0082] A sensor housing 56 (corresponding to the "housing" of the present invention) is defined by a partition wall 55 within the side frame 18 at a position corresponding to the left side of the carrier roller 3c. This sensor housing 56 opens upward through a communication hole 18g formed through an upper surface 18e of the side frame 18. The rotation amount sensor 28 configured as a photoelectric sensor and a drive unit 57 are disposed within the sensor housing 56, and the communication hole 18g is closed by a shielding plate 58 disposed from above. The rotation amount sensor 28 is fixed to the underside of the shielding plate 58, with the light-emitting portion and the light-receiving portion facing rightward. The underside of the shielding plate 58 is connected to a shaft 60 of the drive unit 57 via a pair of left and right interlocking arms 59. Drive of the drive unit 57 around the shaft 60 causes the shielding plate 58 to open and close between a closed position indicated by a two-dot chain line in FIG. 17 and an open position indicated by a solid line.

[0083] When the shielding plate 58 is in the closed position, the communication hole 18g is closed and the rotation amount sensor 28 is stored in the sensor housing portion 56, and this shielding plate 58 isolates the sensor housing portion 56 from the outside, preventing the intrusion of dust and the like. When the shielding plate 58 is in the open position, the communication hole 18g is opened and the rotation amount sensor 28 is pulled upward from the sensor housing portion 56 together with the shielding plate 58, so that its light-emitting portion and light-receiving portion face the left side surface of the carrier roller 3c and can detect the reflector 41.

[0084] 8, in this embodiment, the rotation amount sensors 28 are always connected to the input side of the controller 43, and the drive units 52, 57 are always connected to the output side of the controller 43. Therefore, during the inspection process, the operation of attaching and detaching the rotation amount sensors 28 described in the first embodiment is not required, and the operation of connecting and disconnecting wiring to and from the controller 43 is not required.

[0085] 19 and 20 are flowcharts showing a track inspection routine executed by the controller 43. The differences from the first embodiment are that processing related to the drive units 52 and 57 has been added, the guidance content of steps S2 and S21 has been changed accordingly, and inspection processing related to the idler 3b and the front and rear carrier rollers 3c is executed in parallel.

[0086] That is, when the inspection start button 44 is operated in step S1, first, the left drive units 52, 57 are driven in step S31 to switch the shielding plates 53, 58 to the open position. This enables the left rotation amount sensors 28 to detect the respective reflectors 34, 41, and the guidance in the subsequent step S2 instructs the left track-type traveling device 3 to be jacked up.

[0087] The subsequent processing of steps S3 to S17 is basically the same as that of the first embodiment, except that it is executed in parallel for the idler 3b and each carrier roller 3c. Therefore, in steps S4 to S8, the rotation amount N of each of the idler 3b and each carrier roller 3c is measured, and in steps S9, S10, and S12, the use limit and presence or absence of a malfunction of the idler 3b and each carrier roller 3c are determined based on each rotation amount N, and whether or not tension adjustment of the crawler belt 3e is required is determined. Each determination situation is the same as that described with reference to FIG. 4 in the first embodiment. Note that, due to the execution of such parallel processing, steps S11 and S14 shown in FIG. 10 are omitted.

[0088] In steps S13, 15 to 17, the inspection results of the idler 3b and each carrier roller 3c are also displayed in parallel on the display 46. For example, messages such as a normal message for the idler 3b and the front carrier roller 3c, a repair message for the rear carrier roller 3c, and a message that tension adjustment of the crawler belt 3e is not required are simultaneously displayed on the display 46, and the operator can determine whether maintenance is required for each item based on this display.

[0089] Then, after the inspection results are displayed, step S18 determines "No" because the right side has not yet been inspected, and the routine proceeds to step S32. In step S32, the left drive units 52 and 57 are driven to switch the shielding plates 53 and 58 to the closed position, and in the following step S31, the right drive units 52 and 57 are driven to switch the shielding plates 53 and 58 to the open position. The guidance in the following step S2 instructs the right tracked traveling device 3 to be jacked up. Thereafter, processing is executed in the same manner as for the left side, and when the determination in step S18 is "Yes," the routine proceeds to step S33, where the right drive units 52 and 57 are driven to switch the shielding plates 53 and 58 to the closed position. In the following step S19, as the termination work, guidance is given on the work content to stop jacking up the right tracked traveling device 3, and then the routine ends. The tension / failure determination value update routine described with reference to FIG. 11 is also executed in the same manner as in the first embodiment.

[0090] As described above, according to this embodiment, the inspection process is performed by jacking up the track-type traveling device 3, so like the first embodiment, the rotation amount N can be measured accurately without being affected by the ground, thereby obtaining accurate inspection results. Various associated effects can also be achieved in the same way as in the first embodiment, although a redundant description will not be given.

[0091] Additionally, the rotation amount sensor 28 is disposed in the sensor housing portions 51, 56 defined in the yoke 21 and the side frame 18, and the shielding plates 53, 58 are switched to the open position to enable detection of the reflectors 34, 41 only when it is necessary to perform an inspection process on the tracked traveling device 3. Therefore, the rotation amount sensor 28 is normally disposed in the sensor housing portions 51, 56 and is protected from dust and the like, and therefore failure of the rotation amount sensor 28 due to this can be prevented in advance.

[0092] Furthermore, during the inspection process, the labor required for the inspection process can be reduced and the inspection can be easily carried out, since there is no need to perform the operation of attaching and detaching the rotation amount sensor 28 as in the first embodiment, and there is no need to perform the operation of connecting and disconnecting wiring to the controller 43. Furthermore, since the rotation amount sensors 28 are provided individually for the idler 3b and the front and rear carrier rollers 3c, the inspection processes for each can be carried out in parallel. Therefore, the time required for the inspection process can be shortened compared to the first embodiment, and the original work of the hydraulic excavator 1 can be started sooner.

[0093] Although the description of the embodiment has been completed, the aspects of the present invention are not limited to this embodiment. For example, in the above embodiment, the measured rotation amount N of the idler 3b and the carrier roller 3c is used to determine the respective usage limits, the presence or absence of a malfunction, and the need for tension adjustment of the crawler belt 3e. However, the present invention is not limited to this. Any of the inspection processes may be omitted, or new inspection processes may be added.

[0094] In the above embodiment, both the left and right track-type traveling units 3 are inspected, but this is not limiting, and only one of the left and right may be inspected. For example, if the left track-type traveling unit 3 is inspected and its idler 3b reaches its service limit, not only the left idler 3b but also the right idler 3b that has been in a similar operating condition may be replaced, and this type of configuration is also included in the present invention.

[0095] In the above embodiment, the controller 43 provides guidance to the operator on jacking up and determines the completion of jacking up based on the operation of the preparation completion button 45, but this is not limiting. For example, the controller 43 may drive and control the hydraulic cylinders 6a to 8a of the swivel device 2a and the front work unit 5 to automatically perform jacking up (corresponding to the "jacking up determination unit" of the present invention). [Explanation of symbols]

[0096] 1. Hydraulic excavator 2 Undercarriage 3 Tracked running device 3a drive sprocket 3b Idler (driven roller) 3c Carrier roller (driven roller) 3e Tracks 4 Upper rotating body 5. Work Front 15 Track adjustment device 24 Stroke sensor (operation amount detection part) 27 Master pin sensor (measurement section detection section) 28 Rotation amount sensor (rotation state detection part) 31, 32 Sensor fixing part (fixing part) 43 Controller 43a Wear amount estimation section 43b Jack-up Judgment Section 43c Use limit determination section 43d Tension adjustment judgment section 43e Failure determination section 43f Failure judgment value update unit 43g Tension judgment value update section 45 Ready button 46 Display (display unit) 51, 56 Sensor housing (housing) 53,58 Shielding plate

Claims

1. A hydraulic excavator in which a track-type traveling device is provided on each of the left and right sides of a lower traveling body, the track-type traveling device being formed by wrapping an endless track around a drive sprocket and a plurality of driven rollers, and an articulated work front is provided by rotatably connecting an upper rotating body to the lower traveling body, a wear amount estimation unit that estimates the wear amount of the driven roller by driving at least one of the left and right tracked traveling devices as an inspection target; a jack-up determination unit that determines a jack-up state in which the work front is brought into contact with the ground and the track-type traveling device to be inspected is separated from the ground; a control device having The wear amount estimation unit estimates the wear amount of the driven roller when the jack-up state determination unit determines that the track-type traveling device to be inspected is in a jack-up state. A hydraulic excavator characterized by:

2. the driven rollers include an idler whose position is displaced in the front-rear direction by a track adjustment device to adjust the tension of the track, and a plurality of rollers disposed between the drive sprocket and the idler; The wear amount estimating unit estimates the wear amount of at least one of the idler and each of the rollers. The hydraulic excavator according to claim 1 .

3. a rotation state detection unit that detects the rotation state of the driven roller; The wear amount estimation unit estimates the wear amount based on the rotation state of the driven roller detected by the rotation state detection unit. The hydraulic excavator according to claim 2 .

4. a fixing portion provided at a position close to the driven roller of the lower traveling body, The rotation state detection unit is detachably fixed to the fixed part and is capable of detecting the rotation state of the driven roller. The hydraulic excavator according to claim 3 .

5. a storage section defined in a position adjacent to the driven roller of the lower traveling body and isolated from the outside when an openable and closable shielding plate is in a closed position; The rotation state detection unit is disposed in the accommodation unit and is capable of detecting the rotation state of the driven roller when the shielding plate is switched to the open position. The hydraulic excavator according to claim 3 .

6. a measurement section detection unit that detects driving of the crawler belt in a predetermined measurement section, the rotation state detection unit is configured as a rotation amount sensor that measures a rotation amount as a rotation state of the driven roller, The wear amount estimation unit determines the amount of rotation measured by the rotation amount sensor in the measurement section detected by the measurement section detection unit as the amount of wear of the driven roller. The hydraulic excavator according to claim 3 .

7. an operation amount detection unit that detects an operation amount of the track adjustment device that correlates with the length of the track; The wear amount estimating unit corrects the rotation amount measured by the rotation amount sensor based on the operation amount of the track adjuster detected by the operation amount detecting unit. The hydraulic excavator according to claim 6 .

8. a use limit determination unit that determines a use limit of the driven roller; The service limit determination unit determines that the driven roller has reached its service limit when the rotation amount of the driven roller estimated as the wear amount by the wear amount estimation unit becomes equal to or greater than a predetermined replacement determination value.

8. The hydraulic excavator according to claim 6 or 7.

9. a tension adjustment determination unit that determines whether or not tension adjustment of the crawler belt is required; The tension adjustment determination unit determines that tension adjustment of the crawler belt is required when the rotation amount of the driven roller estimated as the amount of wear by the wear amount estimation unit becomes equal to or greater than a predetermined tension determination value. The hydraulic excavator according to claim 8 .

10. a failure determination unit that determines whether or not the driven roller has a failure; The failure determination unit determines that a failure has occurred in the driven roller when the rotation amount of the driven roller estimated as the wear amount by the wear amount estimation unit becomes equal to or less than a preset failure determination value. The hydraulic excavator according to claim 9 .

11. The present invention further includes a tension determination value update unit that updates the tension determination value by adding a preset increment when the track tension is adjusted by the track adjustment device based on the determination by the tension adjustment determination unit. The hydraulic excavator according to claim 9 or 10.

12. The vehicle further includes a failure determination value update unit that updates the failure determination value by subtracting a predetermined decrease amount from the failure determination value when the track tension is adjusted by the track adjustment device based on the determination by the tension adjustment determination unit. The hydraulic excavator according to claim 10.

13. A display that can be seen by the operator of the hydraulic excavator, a ready button for inputting completion of the jacking up; Furthermore, The jack-up determination unit instructs the operator to jack up the vehicle using the display unit, and determines that the vehicle is in the jack-up state when the preparation completion button is operated thereafter. The hydraulic excavator according to any one of claims 1 to 12.

14. The wear amount estimation unit inspects both the left and right track-type traveling devices. The hydraulic excavator according to any one of claims 1 to 13.

Images