Slewing device and construction machine

Abstract

To provide a revolving machine capable of accurately diagnosing a state of lube oil of a speed reducer without requiring a pump driven by an external driving force, and a construction machine loaded therewith.SOLUTION: A revolving machine 11 has a hydraulic motor 16, a gear reducer 44 having a carrier 46D driven by the hydraulic motor, and has an impeller 71 fitted to the carrier 46D in a housing 12 of the gear reducer and an upper opening 64 positioned outside the impeller in the radial direction of the carrier, an oil passage structure 67 forming the oil passage circulating lube oil filled in the housing 12 via housing outside, and a contamination center 62 installed in the oil passage structure and detecting foreign matters in the lube oil flowing through the oil passage structure.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a slewing device including a speed reducer connected to a hydraulic motor for driving a slewing body, and a construction machine equipped with the slewing device.

Background Art

[0002] In a construction machine including a hydraulic excavator, a speed reducer may be mounted as a power transmission device for transmitting the power of a prime mover such as a hydraulic motor by gears or the like. Lubricating oil for lubricating gears, bearings, etc. is enclosed in the case of the speed reducer. Since the speed reducer cannot prevent wear of gears and the like, foreign matters such as metal and broken pieces generated by wear are mixed into the lubricating oil. When foreign matters are mixed into the lubricating oil, there is a possibility of damaging gears, bearings, oil seals, etc.

[0003] Although not related to the technology of construction machines, for example, Patent Document 1 discloses a lubricating oil diagnosis system including a lubricating oil using device (rotating machine), a lubricating oil tank for storing lubricating oil supplied to the lubricating oil using device, a circulation line through which the lubricating oil circulated between the lubricating oil tank and the lubricating oil using device flows, a pump provided in the circulation line for circulating the lubricating oil toward the lubricating oil using device, a filter disposed in the circulation line, and a sensor for measuring the characteristics of the lubricating oil, for diagnosing the state of the lubricating oil of a rotating machine.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the lubricating oil diagnostic system of Patent Document 1 requires a pump driven by external power to supply lubricating oil to the sensor, and there is room for improvement from the viewpoints of space saving, energy saving, and maintenance when mounted on a construction machine.

[0006] An object of the present invention is to provide a slewing device and a construction machine that can accurately diagnose the state of the lubricating oil of a speed reducer without requiring a pump driven by external driving force.

Means for Solving the Problems

[0007] This application includes a plurality of means for solving the above problems. For example, it is mounted on a construction machine including a lower traveling body and an upper slewing body rotatably supported with respect to the lower traveling body, and includes a hydraulic motor and a gear speed reducer having a rotating shaft driven by the hydraulic motor. In a slewing device of a construction machine for slewing the upper slewing body, an impeller attached to the rotating shaft in a housing covering the gear speed reducer and rotating with the rotation of the rotating shaft; an upper opening located outside the impeller in the radial direction of the rotating shaft; and an oil passage structure for circulating the lubricating oil filled in the housing to the outside of the housing; and a sensor provided in the oil passage structure for detecting foreign matter in the lubricating oil flowing through the oil passage structure. , the gear reducer is a planetary gear mechanism having a carrier connected to the rotating shaft, and further includes a first bearing located below the carrier and supporting the rotation of the rotating shaft, and a second bearing located below the first bearing and supporting the rotation of the rotating shaft. The impeller is attached between the lower end of the carrier and the first bearing in the central axis direction of the rotating shaft. shall be.

Effects of the Invention

[0008] According to the present invention, it is possible to accurately diagnose the state of the lubricating oil of the speed reducer with space saving and energy saving without requiring a pump driven by external driving force.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

MODE FOR CARRYING OUT THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0011] FIG. 1 is a side view schematically showing the appearance of a hydraulic excavator 1 which is an example of a construction machine according to the present embodiment. In the following, a hydraulic excavator equipped with a bucket as an attachment located at the tip of the front working device will be described, but the attachment can be replaced with various ones such as a grapple, a breaker, and a lifting magnet in addition to the bucket.

[0012] The hydraulic excavator 1 includes a self - propelled crawler - type lower traveling body 2 and an upper slewing body 3 that is supported on the lower traveling body 2 so as to be slewing - capable with respect to the lower traveling body 2. On the front side of the upper slewing body 3, a working device 4 is attached so as to be capable of pitching motion, and this working device 4 is operated by an operator to perform excavation work and the like. A slewing ring 5 is provided between the lower traveling body 2 and the upper slewing body 3, and the upper slewing body 3 is supported on the lower traveling body 2 so as to be slewing - capable via the slewing ring 5. A slewing device 11 for driving the upper slewing body 3 to slew left and right is mounted on a slewing frame 3A that serves as the base of the upper slewing body 3.

[0013] Further, the upper slewing body 3 is equipped with a controller 30 that performs a process of diagnosing an abnormality of a speed reducer 44 (described later) included in the slewing device 11 based on the state of lubricating oil, and a wireless communication device 33 for mutually communicating data processed by the controller 30 with an external terminal. The controller 30 includes a processor (for example, a CPU) and a storage device (for example, a memory), and the processor executes various processes based on a program stored in the storage device.

[0014] FIG. 2 is a cross - sectional view of the slewing device 11 and the slewing ring 5 mounted on the hydraulic excavator of FIG. 1.

[0015] (Slewing ring 5) The slewing ring 5 includes an inner ring 5A fixed on a support cylinder 2A (refer to FIG. 1) of the lower traveling body 2, an outer ring 5B fixed on the lower surface side of the slewing frame 3A, and a large number of steel balls 5C (only one is shown in FIG. 3) provided between the inner ring 5A and the outer ring 5B. Inner teeth 5D are formed over the entire circumference on the inner peripheral side of the inner ring 5A. When a pinion 40B provided at the lower end of the output shaft 40 of the slewing device 11 is rotated by the operation of the slewing device 11, the outer ring 5B fixed to the slewing frame 3A rotates around the inner ring 5A, so that the upper slewing body 3 performs a slewing operation on the lower traveling body 2.

[0016] (Slewing device 11) The slewing device 11 includes a hydraulic motor 16, a speed reducer 44 having a rotating shaft (for example, the second carrier 46D and the output shaft 40 described later) driven by the hydraulic motor 16, and a housing 12 that covers the speed reducer 44. By driving the hydraulic motor 16, the upper slewing body 3 is slewed. The housing 12 is filled with lubricating oil (not shown), which lubricates the gears and bearings in the speed reducer 44.

[0017] (Speed reducer 44) The speed reducer 44 reduces the rotation input from the hydraulic motor 16 and outputs it to the output shaft 40. The speed reducer 44 of the present embodiment is a gear speed reducer and includes a first planetary gear mechanism 45 located at the uppermost stage (the first stage) and a second planetary gear mechanism 46 located at the stage next to the uppermost stage (the second stage).

[0018] (First planetary gear mechanism 45) The first planetary gear mechanism 45 includes a first sun gear 45A fixed to the output shaft (rotating shaft) of the hydraulic motor 16, a plurality of first planetary gears 45B (in the illustrated example, there are three planetary gears 45B) that mesh with the first sun gear 45A and rotate while revolving and rotating around the first sun gear 45A, a first internal gear 45C that meshes with the plurality of first planetary gears 45B and is fixed to the housing 12 of the speed reducer 44, and a first carrier 45D that is fixed to a plurality of first planetary gear pins inserted into the rotation center portion of the first planetary gears 45B and can rotate at the revolving speed of the first planetary gears 45B.

[0019] (Second planetary gear mechanism 46) The second planetary gear mechanism 46 includes a second sun gear 46A fixed to the first carrier 45D, a plurality of second planetary gears 46B that mesh with the second sun gear 46A and rotate while revolving and rotating around the second sun gear 46A, a second internal gear 46C that meshes with the plurality of second planetary gears 46B and is fixed to the housing 12, and a second carrier 46D that is fixed to a plurality of second planetary gear pins inserted into the rotation center portion of the second planetary gears 46B and can rotate at the revolving speed of the second planetary gears 46B.

[0020] The second carrier 46D is connected to the output shaft 40 of the speed reducer 44. A plurality of bearings 41, 42 for supporting the rotation of the output shaft 40 are provided around the output shaft 40. A pinion 40B is provided at the lower end of the output shaft 40. By rotating the pinion 40B by the driving force of the hydraulic motor 16, the upper swing body 3 swings (rotates). Note that the dashed-dotted line 40C in the figure is the central axis (rotation axis) of the output shaft 40.

[0021] Further, the speed reducer 44 is attached to the lower end portion of the second carrier 46D (rotating shaft) in the housing 12 and includes an impeller 71 as a blade-like protrusion that rotates with the rotation of the second carrier 46D, and an upper opening 64 located outside the impeller 71 in the radial direction of the second carrier 46D and the output shaft 40. It includes an oil passage structure body 67 that constitutes an oil passage for circulating the lubricating oil filled in the housing 12 via the outside of the housing 12, and a sensor 62 provided in the oil passage structure body 67 for detecting foreign matter in the lubricating oil flowing through the oil passage structure body 67.

[0022] (Impeller 71) FIG. 3 is a perspective view of the impeller (impeller) 71. The impeller 71 includes an annular boss 46F provided with a hole 78 into which the second carrier 46D (output shaft 40) is inserted and fixed, a disk-shaped shell 73 provided around the boss 46F, and a plurality of blades 72 that rise from the upper surface of the shell 73 and whose inner diameter-side ends are connected to the boss 46F. When the second carrier 46D rotates by the driving force of the hydraulic pump 16, the impeller 71 also rotates, and the lubricating oil is discharged toward the outside in the radial direction of the impeller 71. That is, the impeller 71 functions as a lubricating oil supply device that supplies lubricating oil to the upper opening 64 of the oil passage structure body 67.

[0023] Each blade 72 protrudes from the shell 73 toward the bottom surface 46E side of the second carrier 46D. In the illustrated example, the number of blades 72 is six, but it may be two or more. Also, in the illustrated example, the inner diameter side end of each blade 72 is connected to the boss 46F, but a gap may be provided between the blade 72 and the boss 46F (see FIG. 10 described later). Further, the illustrated impeller 71 is formed such that its outer diameter decreases as it goes downward in the impeller axis direction so as to follow the shape of the inner peripheral wall of the housing 12. However, the shape of the impeller 71 is not limited to this, and for example, there may be no change in the outer diameter in the impeller axis direction (that is, the outer diameter may be constant).

[0024] (Upper shroud 81A · Lower shroud 81B) Returning to FIG. 2, the speed reducer 44 preferably includes an annular member attached to the inner peripheral wall of the housing 12, an upper shroud 81A located above the impeller 71, and an annular member attached to the inner peripheral wall of the housing 12, a lower shroud 81B located below the impeller 71. By providing the upper shroud 81A and the shroud 81B so as to cover the upper and lower portions of the impeller 71 between the inner peripheral wall of the housing 12 and the rotating shaft (output shaft) 40 in this way, the lubricating oil supply force of the impeller 71 to the oil passage structure 67 can be improved. Note that the upper surface of the upper shroud 81A is preferably provided with a downward gradient toward the impeller 71. This is to suppress the accumulation of foreign matter on the upper shroud 81A. Also, the inner diameter side ends of the upper shroud 81A and the lower shroud 81B are preferably brought as close as possible to the rotating body located inside thereof within a range where they do not contact the rotating body.

[0025] (Oil passage structure 67) The upper opening 64 is a through-hole provided in the housing 12 and is the inlet of the oil passage structure 67, and is located radially outside the impeller 71 in the housing 12. Below the upper opening 64 in the housing 12, a lower opening 65, which is a similar through-hole, is provided. The lower opening 65 shown in FIG. 2 opens between the two bearings 41 and 42, but it may also open between the impeller 71 and the bearing 41. From the viewpoint of suppressing the deposition of foreign matter, it is preferable that the upper opening 64 and the lower opening 65 are provided with a downward gradient along the flow direction of the lubricating oil as shown in FIG. 2. That is, the bottom of the upper opening 64 slopes downward from the inside to the outside of the housing 12, and the bottom of the lower opening 65 slopes downward from the outside to the inside of the housing 12.

[0026] The oil passage structure 67 is a substantially tubular structure that connects the space between the upper opening 64 and the lower opening 65 outside the housing 12. The oil passage structure 67 includes an introduction flow path portion 67A that connects the upper opening 64 and the sensor 62, a sensor internal flow path portion 67C (see FIG. 4) that is connected to the introduction flow path portion 67A and passes through the inside of the sensor 62, and a discharge flow path portion 67B that connects the outlet of the sensor internal flow path portion 67C and the lower opening 65.

[0027] The introduction flow path portion 67A is preferably provided with a downward gradient from the upper opening 64 to the sensor 62, and the discharge flow path portion 67B is preferably provided with a downward gradient from the outlet of the sensor internal flow path portion 67C to the lower opening 65. This is to suppress the deposition of foreign matter.

[0028] FIG. 4 is a cross-sectional view of the sensor 62 as viewed from the direction of the arrow X shown in FIG. 2. As shown in this figure, the sensor internal flow path portion 67C is preferably provided so as to be orthogonal to the axial direction 40C of the rotation shaft 40 when viewed from the side of the housing 12. The reason is to improve the detection accuracy of foreign matter by the sensor 62.

[0029] (Sensor 62) The sensor 62 is an oil contamination sensor capable of detecting the number and size of foreign matters (e.g., wear powder of gears) in the lubricating oil passing through the internal flow path portion 67C of the sensor. The sensor 62 is connected to the controller 30, and the detection data collected by the sensor 62 is stored in the controller 30. As the contamination sensor 62, for example, an optical type or an eddy current type can be used. When the sensor 62 is of the optical type, foreign matters other than metal can be measured, but since air bubbles are captured as foreign matters, it is preferable to use a device or data processing for removing air bubbles. In the eddy current type, foreign matters other than metal cannot be detected, but water and air bubbles are not detected as foreign matters, so special devices or data processing are not required. Any type of contamination sensor may be used, but the sensor 62 in FIG. 4 is an eddy current type contamination sensor.

[0030] Note that in order to ensure the accuracy of the abnormality diagnosis, it is preferable to perform sensing in a state where the flow rate of the lubricating oil passing through the sensor 62 exceeds a predetermined threshold value. Therefore, a flow rate sensor 68 (see FIG. 4) is provided on the upstream side of the sensor 62 (i.e., the introduction flow path portion 67A), and it is preferable to detect foreign matters while the flow rate of the lubricating oil exceeds the threshold value.

[0031] (Foreign matter collection unit 63) It is preferable to provide a foreign matter collection unit 63 for collecting foreign matters in the lubricating oil in the discharge flow path portion 67B located on the downstream side of the sensor 62. This is because damage to the bearing and the meshing surface of the gears caused by continuous use of the lubricating oil mixed with foreign matters in the housing 12 is reduced. As the foreign matter collection unit 63, for example, a magnet or a filter can be used, but among these two, a magnet that is less likely to cause flow path resistance than a filter is preferable.

[0032] Note that as shown in the example of FIG. 2, it is preferable to provide valves 66 as opening / closing mechanisms upstream and downstream of the foreign matter collection unit 63. When both valves 66 are closed when removing the foreign matter collection unit 63 from the flow path portion 67B during maintenance or the like, the outflow of the lubricating oil during the removal of the foreign matter collection unit 63 is suppressed, making the work easier. As the valve 66, a check valve (non-return valve) or a stop valve (flow rate adjustment valve) can be used.

[0033] [Operation] The operation of the speed reducer 44 (swivel device 11) configured as described above will be described. When each gear in the speed reducer 44 rotates due to the rotation of the hydraulic motor 16, as the operation time elapses, each gear wears out and wear debris (metal particles) settles to the lower part inside the speed reducer 44. However, further settlement of this wear debris inside the speed reducer 44 is prevented by the shell 73 of the impeller 71 provided directly below the second carrier 46D, and most of the wear powder is fed by the impeller 71 having the hydraulic motor 16 as a drive source toward the upper opening 64 located on the outer side in the radial direction of the impeller 71. The wear powder is introduced from the upper opening 64 into the oil passage structure 67, reaches the sensor 62, and after the size is detected and the number is counted by the sensor 62, it is collected by the foreign matter collection part 63. The lubricating oil from which the wear powder has been collected and purified is returned again into the housing 12 through the lower opening 65 and used for lubricating gears and the like.

[0034] The data (detection result) detected by the sensor 62 and the abnormality diagnosis of the speed reducer 44 based on the detection data may be performed by the controller 30 mounted on the hydraulic excavator 1, or may be performed by a terminal such as an external computer. When performing the latter, the movement of the detection data may be, for example, sequentially transmitted to an external terminal via the wireless communication device 33 mounted on the hydraulic excavator 1, or may be performed by periodically copying or moving the detection data to a recording medium by a service technician or the like. That is, when transmitting sensor data or diagnosis data to the outside, it is sufficient that the hydraulic excavator 1 is provided with a communication device such as the wireless communication device 33 that transmits the detection result of the sensor 62 to the outside.

[0035] When counting the number of metal particles based on the detection data of the sensor 62 by the controller 30 or the external terminal, it is preferable to classify the particle sizes into several categories and count the number of particles in each category. The counting period (i.e., the data acquisition period) is preferably determined in advance (for example, 30 seconds). Also, since the number of particles counted varies depending on the flow rate of the lubricating oil, it is preferable to also acquire the flow rate data of the lubricating oil at that time and correct the number of particles to a value considering the flow rate. As such correction, for example, there is one that divides the count number by the flow rate.

[0036] [Effect] In the speed reducer 44 (swivel device 11) of the present embodiment, by attaching the impeller 71 to the second carrier 46D, it is possible to provide a pump (lubricating oil supply structure) for feeding the lubricating oil to the sensor 62 in the empty space within the speed reducer 44. As a result, even without a pump driven by external power, it is possible to create a flow (flow velocity) for feeding the lubricating oil to the sensor 62, and the amount of wear powder contained therein can be accurately grasped by the sensor 62. Therefore, according to the present embodiment, the state of the lubricating oil of the speed reducer 44 can be accurately diagnosed without the need for an external pump, and space saving, energy saving, and maintenance reduction can be achieved compared to the past. Also, according to the present embodiment, since the amount of wear powder in the lubricating oil can always be grasped, it is possible to detect the presence or absence of damage to the gears, bearings, etc. that make up the speed reducer 44 at an early stage. Also, an appropriate inspection timing can be known from the measurement results. Further, since the present embodiment can be configured by modifying an existing swivel device, there is also the merit that it is easy to introduce.

[0037] <Second Embodiment> In the above-described first embodiment, there was one upper opening 64, but considering that the hydraulic motor (swivel hydraulic motor) 16 of the hydraulic excavator 1 rotates in two directions, forward and reverse, two upper openings 64, which are the inlets of the introduction flow path portion, may be provided according to the rotation direction of the hydraulic motor 16. Here, the speed reducer in the case where two upper openings 64 are provided will be described as the second embodiment. Note that the same parts as in the previous drawings may be denoted by the same reference numerals and the description may be omitted, and this will also be the same for the third embodiment and later.

[0038] Figures 5 and 6 are cross-sectional views of the speed reducer 44 of the second embodiment in the vicinity of the impeller 71. FIG. 5 shows the case where the impeller 71 rotates in the direction indicated by the arrow 76A in the figure (the first direction (forward rotation direction)), and FIG. 6 shows the case where the impeller 71 rotates in the direction indicated by the arrow 76B in the figure (the second direction (reverse rotation direction)).

[0039] As shown in these figures, the housing 12 is provided with two upper openings, a first upper opening 64A and a second upper opening 64B, and each upper opening 64A, 64B has an opening end on the inner peripheral wall and the outer peripheral wall of the housing 12.

[0040] It is preferable to provide a partition wall 74 between the two upper openings 64A, 64B in the circumferential direction of the housing 12. By providing the partition wall 74 in this way, it becomes easier for lubricating oil to be introduced into each opening 64A, 64B. In the examples of FIGS. 5 and 6, two partition walls 74 are provided, but the two partition walls 74 may be integrated.

[0041] The introduction flow path portion 67A includes a first flow path portion 67A1 that is connected to the first upper opening 64A and into which lubricating oil is introduced when the impeller 71 rotates in the forward rotation direction 76A, a second flow path portion 67A2 that is connected to the second upper opening 64B and into which lubricating oil is introduced when the impeller 71 rotates in the reverse rotation direction 76B, and a confluence flow path portion 67A3 that connects the confluence portion of the first flow path portion 67A1 and the second flow path portion 67A2 to the inlet of the sensor internal flow path portion 67C.

[0042] The first flow path portion 67A1 is a flow path that extends from the first upper opening 64A along the direction of the velocity vector generated at the outer diameter side end portion of the impeller 71 when the impeller 71 is rotated in the forward rotation direction 76A. That is, the first flow path portion 67A1 extends from the first upper opening 64A in the tangential direction of the inner peripheral wall of the housing 12 in the same direction as the forward rotation direction 76A. Note that the extending direction of the first flow path portion 67A1 does not need to completely coincide with the direction of the velocity vector, and any direction that is close to the direction of the velocity vector and in which lubricating oil is easily introduced when the impeller 71 rotates in the forward rotation direction 76A is acceptable.

[0043] The second flow path portion 67A2 is a flow path extending from the second upper opening 64B along the direction of the velocity vector generated at the outer diameter side end of the impeller 71 when the impeller 71 is rotated in the reverse rotation direction 76B. That is, the second flow path portion 67A2 extends in the reverse rotation direction 76B and the forward direction among the tangential directions of the inner peripheral wall of the housing 12 from the second upper opening 64B. Note that the extending direction of the second flow path portion 67A2 does not necessarily have to completely coincide with the direction of the velocity vector, and it may be a direction close to the direction of the velocity vector and in which lubricating oil is easily introduced when the impeller 71 rotates in the reverse rotation direction 76B.

[0044] At the confluence of the first flow path portion 67A1 and the second flow path portion 67A2, it is preferable to provide a movable valve 75 that connects the confluence flow path portion 67A3 to either the first flow path portion 67A1 or the second flow path portion 67A2 according to the rotation direction of the impeller 71. The movable valve 75 receives the flow of lubricating oil and rotates about the support shaft 77 as the axis, and can be switched to either the first position shown in FIG. 5 or the second position shown in FIG. 6. When the movable valve 75 is in the first position in FIG. 5, the second flow path portion 67A2 is blocked by the movable valve 75, and the first flow path portion 67A1 is opened. When the movable valve 75 is in the second position in FIG. 6, the first flow path portion 67A1 is blocked by the movable valve 75, and the second flow path portion 67A2 is opened.

[0045] [Operation and Effect] In the speed reducer 44 configured as described above, when the hydraulic motor 16 rotates in the forward rotation direction 76A according to the turning operation of the operator of the hydraulic excavator 1, the impeller 71 also rotates in the forward rotation direction 76A as shown in FIG. 5, and lubricating oil is introduced into the first flow path portion 67A1 and the lubricating oil flows along the direction of arrow 82A. On the other hand, when the hydraulic motor 16 rotates in the reverse rotation direction 76B, the impeller 71 also rotates in the reverse rotation direction 76B as shown in FIG. 6, and lubricating oil is introduced into the second flow path portion 67A2 and the lubricating oil flows along the direction of arrow 82B. That is, according to the speed reducer 44 of the present embodiment, lubricating oil can be supplied to the sensor 62 smoothly regardless of the direction in which the hydraulic motor 16 rotates according to the operation of the operator, so that the presence or absence of an abnormality in the speed reducer 44 can be diagnosed promptly.

[0046] <Third Embodiment> FIG. 8 is a network configuration diagram of a plurality of computers (including the controller 30) used in the third embodiment of the present invention. As shown in this figure, in this embodiment, in addition to the controller 30, a server computer 104, an administrator computer 112, and a service computer 111 are used. The arrows in the figure indicate the flow of data. Similar to the controller 30, each of the computers 104, 112, and 111 is provided with a processor (e.g., a CPU) and a storage device (e.g., a memory), and is configured such that the processor can execute various processes based on a program stored in the storage device.

[0047] In this embodiment, the detection data of the contamination sensor 62 collected by the controller 30 of the hydraulic excavator 1 and the flow rate sensor 68 installed upstream thereof are transmitted to a server computer (hereinafter referred to as a server) 104 by a communication device such as a wireless communication device 33. Based on the data, the server 104 diagnoses the lubricating oil of the hydraulic excavator 1, and transmits the diagnosis result to the administrator computer 112 and the service computer 111. Here, the flow of the lubricating oil diagnosis performed by the server 104 will be described with reference to FIG. 7. The processing according to the flow of FIG. 7 can also be executed by the controller 30, and it is also possible to mount a computer in the sensor 62 and execute the processing by the computer.

[0048] FIG. 7 is a flowchart of the diagnostic process of the speed reducer 44 based on the lubricating oil performed by the server 104. The process of FIG. 7 is a repetitive process. After the operation of the hydraulic excavator 1, the process is started, and the data collected by the sensor 62 is transmitted to the server 104 at a predetermined time interval set by a timer or the like, for example, every hour, and the server 104 performs a diagnostic process based on the data.

[0049] The server 104 (the same applies to the processor for the following processes) first determines in S103 whether the amount of lubricating oil introduced into the contaminant sensor 62 exceeds a preset threshold based on the data of the flow rate sensor 68 of the hydraulic excavator 1. If the amount of lubricating oil exceeds the threshold, the process proceeds to S106. If the amount of lubricating oil is below the threshold, it waits until the next processing start timing.

[0050] In S106, the server 104 starts counting the number of foreign objects in the lubricating oil based on the data of the contaminant sensor 62, and determines whether a change index value indicating the degree of change from the number of foreign objects counted in the past to the number of foreign objects counted this time exceeds a preset threshold (S107). As the change index value, for example, the difference between the previous measurement value and the current measurement value, the number of measurement value changes per unit time obtained by dividing the difference by the operating time, the moving average of the measurement values of the most recent predetermined number of times, etc. can be used. FIG. 9 shows an example of the change in the number of foreign objects counted by the contaminant sensor 62, and shows the change in the slope of the count number, which is the number of measurement value changes per unit time, in the figure. In the example of this figure, it can be seen that as the operating time increases, the number of foreign objects counted tends to increase, and the slope of the count number changes significantly at a certain operating time.

[0051] In this embodiment, the server 104 diagnoses an abnormality when the change index value increases by more than 10% compared to the previous value in the process of S107, and proceeds to S110 when the change in the change index value exceeds 10%. On the other hand, when the change in the change index value is 10% or less, the server 104 determines that the state of the speed reducer 44 is normal (no damage to the gears) and proceeds to S112.

[0052] In S110, the server 104 notifies the administrator computer 112 and the service computer 111 that an abnormality has occurred in the speed reducer 44 of the hydraulic excavator 1. As a result, the operation of the hydraulic excavator 1 is stopped, and the slewing device 11 is disassembled to check the state of the gears.

[0053] In S112, the server 104 stores the measured value of the foreign object and waits until the next processing start timing.

[0054] When the abnormality diagnosis is performed by the server 104 as described above, the abnormality of the speed reducer 44 can be detected at an early stage, and an increase in the downtime of the hydraulic excavator 1 can be suppressed.

[0055] <Fourth Embodiment> FIG. 10 is a perspective view of the impeller 71A according to the fourth embodiment of the present invention. A gap 79 is provided between the blade 72 of the impeller 71A and the boss 46F. By providing the gap 79 in this way, it is possible to suppress foreign matter (metal particles) that settles from staying on the inner peripheral side (near the boss 46F) of the impeller 71A, and more foreign matter can be fed to the sensor 62 than in the first embodiment.

[0056] <Fifth Embodiment> FIG. 11 is a cross-sectional view of the slewing device 11 according to the fifth embodiment of the present invention. As shown in this figure, the slewing device 11 of this embodiment is characterized in that multi-stage impellers 71B and 71C are provided at the lower end portion of the second carrier 46D. In the illustrated example, two-stage impellers 71B and 71C are attached, and the second impeller 71C is located below the first impeller 71B.

[0057] FIG. 12 is a perspective view of the impellers 71B and 71C of this embodiment, and FIG. 13 is a cross-sectional view of the impellers 71B and 71C of FIG. 12.

[0058] The first impeller (first-stage impeller) 71B has a disk-shaped first shell 73a provided around the boss 46F, a plurality of first blades 72a attached to the upper surface of the first shell 73a, and a plurality of holes 91 provided between the plurality of first blades 72a in the first shell 73a. The plurality of holes 91 communicate with the second impeller 71C.

[0059] The second impeller (second-stage impeller) 71C has a disk-shaped second shell 73b provided around the boss 46F and a plurality of second blades 72b attached to the upper surface of the second shell 73b. The second shell 73b is not provided with holes 91.

[0060] Due to the installation space of the two impellers 71B and 71C, the heights of the blades 72a and 72b of each impeller 71B and 71C are lower than those of the blade 72 in the first embodiment.

[0061] Note that the second blade 72b is provided at a position different from that of the first blade 72a in the circumferential direction of the impeller, but it may be provided at the same position. Also, a gap 79 may be provided between a part or all of the blades 72a and 72b and the boss 46F as in the fourth embodiment.

[0062] Even if the two-stage impellers 71B and 71C are configured in this way, lubricating oil can be supplied to the sensor 62. In particular, in the second impeller 71C, since the first shell 73a of the first impeller 71B and its own second shell 73b serve as a shroud, the lubricating oil supply force can be improved.

[0063] Note that since the multi-stage impellers 71B and 71C in this embodiment have a complicated shape, it is preferable to manufacture them with a metal 3D printer in consideration of the manufacturing cost.

[0064] <Other> Note that in the above, the impeller 71 is attached to the second carrier 46D of the second planetary gear mechanism 46, but the impeller 71 may be attached to any rotating shaft within the allowable space as long as it is a rotating shaft in the speed reducer 44.

[0065] The present invention is not limited to the above-described embodiments, and various modifications within the scope not departing from the gist thereof are included. For example, the present invention is not limited to those having all the configurations described in the above embodiments, and those in which a part of the configurations is deleted are also included. Also, a part of the configuration according to one embodiment can be added to or replaced with the configuration according to another embodiment.

[0066] In addition, each component related to the above-described controllers 30 and server 104, the functions of each of these components, the execution processes, etc. may be realized in part or in whole by hardware (for example, designing the logic for executing each function with an integrated circuit). Further, the components related to the controllers 30 and server 104 may be a program (software) in which each function related to the components of the controllers 30 and server 104 is realized by being read and executed by an arithmetic processing unit (for example, a CPU). Information related to the program can be stored, for example, in a semiconductor memory (flash memory, SSD, etc.), a magnetic storage device (hard disk drive, etc.), and a recording medium (magnetic disk, optical disk, etc.).

[0067] Also, in the description of each of the above embodiments, the control lines and information lines are shown as those considered necessary for the description of the embodiment, but do not necessarily show all the control lines and information lines related to the product. In reality, it is reasonable to consider that almost all components are interconnected.

Explanation of Reference Numerals

[0068] 1…Hydraulic excavator, 3…Upper slewing structure, 3A…Slewing frame, 5…Slewing ring, 5A…Inner ring, 5B…Outer ring, 5C…Steel ball, 5D…Internal teeth, 11…Slewing device, 12…Housing, 16…Hydraulic motor (slewing hydraulic motor), 30…Controller, 33…Wireless communication device, 40…Output shaft, 44…Reducer, 45…First planetary gear mechanism, 45A…First sun gear, 45B…First planetary gear, 45C…First internal gear, 45D…First carrier, 46…Second planetary gear mechanism, 46A…Second sun gear, 46B…Second planetary gear, 46C…Second internal gear, 46D…Second carrier, 46E…Carrier bottom surface, 46F…Boss, 62…Contamination sensor (sensor), 63…Foreign object collection part, 64…Upper opening, 64A…First upper opening, 64B…Second upper opening, 65…Lower opening, 66…Valve, 67…Oil passage structure, 67A…Introduction flow path part, 67A1…First flow path part, 67A2…Second flow path part, 67A3…Confluence flow path part, 67B…Discharge flow path part, 67C…Sensor internal flow path part, 68…Flow rate sensor, 71…Impeller (fan), 71A…Impeller, 71B…First impeller (first-stage impeller), 71C…Second impeller (second-stage impeller), 72…Blade, 72a…First blade, 72a…Second blade, 73…Shell, 73a…First shell, 73b…Second shell, 74…Partition wall, 75…Movable valve, 76A…Forward rotation direction, 76B…Reverse rotation direction, 77…Support shaft, 78…Hole, 79…Gap, 81A…Shroud upper part, 81B…Shroud lower part, 91…Hole, 104…Server computer (server)

Claims

1. It is mounted on a construction machine including a lower traveling body and an upper revolving body rotatably supported with respect to the lower traveling body, and includes a hydraulic motor and a gear reducer having a rotating shaft driven by the hydraulic motor. In a slewing device of a construction machine for slewing the upper revolving body, An impeller attached to the rotating shaft in a housing covering the gear reducer and rotating with the rotation of the rotating shaft; An oil passage structure having an upper opening located outside the impeller in the radial direction of the rotating shaft and circulating the lubricating oil filled in the housing via the outside of the housing; And a sensor provided in the oil passage structure for detecting foreign matter in the lubricating oil flowing through the oil passage structure. The gear reducer is a planetary gear mechanism having a carrier connected to the rotating shaft. Further provided with a first bearing located below the carrier and supporting the rotation of the rotating shaft, and a second bearing located below the first bearing and supporting the rotation of the rotating shaft. The impeller is attached between the lower end of the carrier and the first bearing in the central axis direction of the rotating shaft, and the slewing device is characterized in this.

2. In the slewing device of Claim 1, The impeller has a disk-shaped shell and a plurality of blades attached to the upper surface of the shell, and the slewing device is characterized in this.

3. In the slewing device of Claim 1, The oil passage structure is An introduction flow path portion connecting the upper opening and the sensor; A sensor internal flow path portion connected to the introduction flow path portion and passing through the inside of the sensor; And a discharge flow path portion connecting the outlet of the sensor internal flow path portion and a lower opening provided below the upper opening, and the slewing device is characterized in this.

4. In the slewing device of Claim 3, The introduction flow path portion is a first flow path portion extending along the direction of the velocity vector generated at the outer diameter side end of the impeller when the impeller rotates in the normal rotation direction, from a first upper opening provided in the housing; a second flow path portion extending along the direction of the velocity vector generated at the outer diameter side end of the impeller when the impeller rotates in the reverse rotation direction, from a second upper opening provided in the housing; a turning device characterized by comprising a confluence portion where the first flow path portion and the second flow path portion merge, and a confluence flow path portion connecting the confluence portion and the inlet of the sensor internal flow path portion.

5. In the turning device according to claim 4, the turning device further comprises a movable valve provided in the confluence portion and connecting the confluence flow path portion to either the first flow path portion or the second flow path portion according to the rotation direction of the impeller.

6. In the turning device according to claim 3, the introduction flow path portion is provided with a downward gradient from the upper opening to the sensor, the sensor internal flow path portion is orthogonal to the axial direction of the rotation axis when viewed from the side of the housing, the discharge flow path portion is provided with a downward gradient from the outlet of the sensor internal flow path portion to the lower opening.

7. In the turning device according to claim 3, the turning device further comprises a foreign matter recovery portion provided in the discharge flow path portion for recovering foreign matters in the lubricating oil.

8. In the turning device according to claim 1, the impeller has a first impeller having a disk-shaped first shell, a plurality of first blades attached to the upper surface of the first shell, and a plurality of holes provided between the plurality of first blades in the first shell; A swivel device having a disk-shaped second shell and a plurality of second blades attached to the upper surface of the second shell, the second impeller being located below the first impeller.

9. In the swivel device according to claim 1, An annular member attached to the inner peripheral wall of the housing, an upper shroud located above the impeller, and An annular member attached to the inner peripheral wall of the housing, a lower shroud located below the impeller, characterized in that the swivel device comprises the same.

10. In the swivel device according to claim 9, The upper surface of the upper shroud is provided with a downward slope toward the impeller, characterized in that the swivel device comprises the same.

11. A construction machine including the swivel device according to claim 1, the lower traveling body and the upper swivel body, and a communication device for transmitting the detection result of the sensor to the outside.

Images