Bearing cleaning apparatus and bearing cleaning method

Abstract

To provide a bearing washing device and a bearing washing method capable of washing a lubricant in a bearing more quickly while suppressing leakage of a washing liquid from the bearing.SOLUTION: The bearing cleaning device 10 includes a cleaning liquid tank 11 for storing a cleaning liquid, a circulation flow passage L for circulating the cleaning liquid between the cleaning liquid tank 11 and the bearing, a pump device 30 for pumping the cleaning liquid in the circulation flow passage L, a pressure detection device 40 for detecting the pressure of the cleaning liquid supplied to the bearing, a direction switching valve 70 capable of reversing the flow direction of the cleaning liquid supplied to the bearing in the circulation flow passage L, and a controller (control device) 80 for controlling the direction switching valve 70 so as to reverse the flow direction of the cleaning liquid supplied to the bearing 1 based on the pressure detected by the pressure detection device 40.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a bearing cleaning device and a bearing cleaning method for cleaning lubricant inside a bearing. [Background technology]

[0002] Conventionally, there are known techniques for cleaning the lubricant inside a bearing with a cleaning liquid. For example, Patent Document 1 describes a flushing device that supplies cleaning oil from a supply port provided in the bearing while using a vacuum pump to suck up the fluid contained in the bearing, thereby preventing the cleaning liquid from leaking from the bearing during cleaning. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-103000 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the process of removing lubricant from bearings using a cleaning liquid, as in the flushing device described in Patent Document 1, can take time. On the other hand, if cleaning liquid is continuously supplied to the inside of the bearing under strong pressure in order to shorten the processing time, this may result in leakage of the cleaning liquid from inside the bearing.

[0005] The present invention has been made in consideration of these problems, and its purpose is to provide a bearing cleaning device and a bearing cleaning method that can more quickly clean the lubricant inside the bearing while suppressing leakage of cleaning fluid. [Means for solving the problem]

[0006] In order to achieve the above object, the bearing cleaning device of the present invention is a bearing cleaning device that cleans the lubricant inside a bearing with cleaning liquid, and is characterized by comprising: a cleaning liquid tank that stores the cleaning liquid; a circulation flow path that circulates the cleaning liquid between the cleaning liquid tank and the bearing; a pump device that pressurizes the cleaning liquid within the circulation flow path; a pressure detection device that detects the pressure of the cleaning liquid supplied to the bearing; a direction switching valve within the circulation flow path that is capable of reversing the flow direction of the cleaning liquid supplied to the bearing; and a control device that controls the direction switching valve to reverse the flow direction of the cleaning liquid supplied to the bearing based on the pressure detected by the pressure detection device.

[0007] In order to achieve the above object, the bearing cleaning method of the present invention involves using a pump device to circulate cleaning liquid within a circulation flow path formed between a cleaning liquid tank that stores the cleaning liquid and a bearing, thereby cleaning the lubricant inside the bearing, and is characterized in that when the pressure of the cleaning liquid supplied to the bearing reaches a predetermined pressure that is set as a value just before leakage of the cleaning liquid from the bearing occurs, a directional switching valve arranged within the circulation flow path reverses the flow direction of the cleaning liquid supplied to the bearing. [Effects of the Invention]

[0008] According to the bearing cleaning device and bearing cleaning method of the present invention, it is possible to more quickly clean the lubricant inside the bearing while suppressing leakage of the cleaning liquid. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic configuration diagram of a bearing cleaning device according to an embodiment. [Figure 2] FIG. 2 is an exploded perspective view showing a bearing to be cleaned by the bearing cleaning device. [Figure 3] FIG. 2 is a cross-sectional view showing a part of a bearing. [Figure 4] FIG. 2 is a schematic diagram showing a probe. [Figure 5] 10 is a flowchart showing a grease replacement process. [Figure 6] 10 is a flowchart showing the procedure of a cleaning process. [Figure 7] FIG. 10 is an explanatory diagram showing a cleaning process in a first flow state. [Figure 8] FIG. 10 is an explanatory diagram showing the cleaning process in the second flow state. [Figure 9] FIG. 10 is an explanatory diagram showing an activator injection process. [Figure 10] FIG. 10 is an explanatory diagram showing a new grease injection process. DETAILED DESCRIPTION OF THE INVENTION

[0010] An embodiment of the present invention will now be described with reference to the drawings. Fig. 1 is a schematic diagram of a bearing cleaning device according to the embodiment. Fig. 2 is an exploded perspective view showing a bearing to be cleaned by the bearing cleaning device. Fig. 3 is a cross-sectional view showing a part of the bearing.

[0011] (bearings) The bearing 1 to be cleaned in this embodiment is a relatively large bearing that supports a rotating body used in construction machinery such as a hydraulic excavator. However, the bearing 1 may also be used in other construction machinery such as dump trucks, wheel loaders, bulldozers, forklifts, and cranes, as well as in generators, turbines, ships, various engines, automobiles, and machine tools.

[0012] As shown in Figures 2 and 3, the bearing 1 comprises an inner ring 2, an outer ring 3, multiple rolling elements 4, multiple supports 5, and two seal members 6. The inner ring 2 and the outer ring 3 each have a groove S1 with a semicircular cross section formed therein, and are arranged concentrically so that the grooves S1 face each other. The multiple rolling elements 4 are supported by the multiple supports 5 and are rotatably arranged along the groove S1 between the inner ring 2 and the outer ring 3. This allows the inner ring 2 and the outer ring 3 to rotate relative to each other via the multiple rolling elements 4.

[0013] A seal member 6 is attached between the inner ring 2 and the outer ring 3 to seal the annular gap S2. The seal member 6 is, for example, a dust seal. In this way, the bearing 1 has a non-contact sealed structure in which the shaft (not shown) and the seal member 6 do not come into contact. The gaps between each rolling element 4 and groove S1, and the internal space 7 including the gap S2, are filled with grease as a lubricant. The outer ring 3 is also formed with two communicating passages 8 that extend from the outer peripheral surface to the groove S1. A grease nipple 9 is fitted into each communicating passage 8, and grease is supplied to and discharged from the internal space 7 via the grease nipple 9.

[0014] (Bearing cleaning equipment) The bearing cleaning device 10 according to the embodiment is a device for cleaning the bearing 1 in order to extend the life of the bearing 1 by periodically replacing the grease in the bearing 1. The bearing cleaning device 10 also functions as an exchange device for replacing the grease in the bearing 1. As shown in FIG. 1 , the bearing cleaning device 10 includes a circulation flow path L, a cleaning liquid tank 11, an activator tank 12, a grease tank (lubricant tank) 13, a connection switching device 20, a pump device 30, a pressure detection device 40, a flow rate detection device 50, a state quantity detection sensor 55, a filter 60, a directional switching valve 70, and a controller (control device) 80.

[0015] The circulation flow path L is a flow path that connects the cleaning solution tank 11, the activator tank 12, and the grease tank 13 to the bearing 1 so that the liquids stored in these tanks can be circulated, and is composed of pipes, hoses, etc. The above-mentioned components of the bearing cleaning device 10, except for the controller 80, are arranged on the circulation flow path L. In the following explanation, the path from the connection switching device 20 (first switching valve 21) connected to the cleaning solution tank 11, the activator tank 12, and the grease tank 13 to the directional switching valve 70 will be referred to as the "first flow path L1," the path from the directional switching valve 70 to the bearing 1 will be referred to as the "second flow path L2," the path from the bearing 1 to the directional switching valve 70 will be referred to as the "third flow path L3," and the path from the directional switching valve 70 to the connection switching device 20 (second switching valve 22) connected to the cleaning solution tank 11, the activator tank 12, and the grease tank 13 will be referred to as the "fourth flow path L4."

[0016] Here, the second flow path L2 and the third flow path L3 are each connected to the grease nipple 9 of the bearing 1 via a probe (connecting member) 90. FIG. 4 is a schematic diagram showing the probes 90. Each probe 90 has an insertion portion 91 that is inserted into the grease nipple 9. The insertion portion 91 is formed with an internal flow path extending from the second flow path L2 or the third flow path L3, and a communication hole 92 that communicates with the internal flow path is formed at the tip of the insertion portion 91. In addition, a plurality of communication holes 93 that communicate with the internal flow path are formed in a line along the axial direction on the side of the insertion portion 91. Each probe 90 communicates the grease nipple 9 with the second flow path L2 or the third flow path L3 via the communication hole 92 or each communication hole 93.

[0017] A heating device 95 is attached to each probe 90. The heating device 95 is, for example, a ceramic heater made of an electric heating wire, and is wrapped around the outer circumferential surface of the probe 90 in front of the insertion portion 91. The heating device 95 is controlled by the controller 80 so as to heat at least the probe 90 that supplies cleaning liquid to the bearing 1 during the execution of the cleaning process ST1, which will be described later.

[0018] Returning to the explanation of Figure 1, the cleaning liquid tank 11 stores a cleaning liquid for dissolving the grease inside the bearing 1. The cleaning liquid may be either an alkaline or acidic solution. The activator tank 12 stores an activator to be injected into the bearing 1 after cleaning. The activator is used to repair the surface condition of the bearing 1 to prevent new grease injected into the bearing 1 from having its lubricating film removed from not sufficiently permeating its internal space 7. Note that if it is possible to sufficiently permeate the new grease into the bearing 1 after cleaning, the injection of the activator may be omitted. The grease tank 13 stores new grease to be injected into the bearing 1 after the activator has been injected.

[0019] The connection switching device 20 includes a first switching valve 21 and a second switching valve 22. The first switching valve 21 is a valve that switches the connection state between the cleaning liquid tank 11, the activator tank 12, and the grease tank 13 and the first flow path L1. The second switching valve 22 is a valve that switches the connection state between the cleaning liquid tank 11, the activator tank 12, and the grease tank 13 and the fourth flow path L4. The first switching valve 21 and the second switching valve 22 are controlled by a controller 80.

[0020] The pump device 30 includes a first pump 31 and a second pump 32. The first pump 31 is disposed on the first flow path L1, and pressurizes the liquid agent flowing out from the first switching valve 21, and supplies it to the directional switching valve 70. The second pump 32 is disposed on the fourth flow path L4, and supplies the liquid agent flowing out from the directional switching valve 70 to the second switching valve 22. A filter 60 is provided between the second pump 32 and the second switching valve 22, and filters the cleaning liquid in which grease has been dissolved.

[0021] The pressure detection device 40 includes a first pressure sensor 41 and a second pressure sensor 42. The first pressure sensor 41 detects the pressure in the second flow path L2. The second pressure sensor 42 detects the pressure in the third flow path L3. The first pressure sensor 41 and the second pressure sensor 42 output the detection results to the controller 80.

[0022] The flow rate detecting device 50 includes a first flow rate sensor 51 and a second flow rate sensor 52. The first flow rate sensor 51 detects the flow rate of the liquid agent flowing through the second flow path L2. The second flow rate sensor 52 detects the flow rate of the liquid agent flowing through the third flow path L3. The first flow rate sensor 51 and the second flow rate sensor 52 output the detection results to the controller 80.

[0023] The state quantity detection sensor 55 is disposed, for example, in the fourth flow path L4, and detects a state quantity of the cleaning liquid flowing through the fourth flow path L4. The state quantity detection sensor 55 is only required to be able to detect at least one of the density, viscosity, temperature, dielectric constant, color difference, and particle amount of the cleaning liquid, and a plurality of state quantity detection sensors may be provided according to the state quantities to be detected. Furthermore, the state quantity detection sensor 55 may be disposed at any position within the circulation flow path L. The state quantity detection sensor 55 outputs the detection result to the controller 80.

[0024] The direction switching valve 70 is a solenoid valve capable of switching the flow of the liquid supplied to the bearing 1 to the reverse direction. In this embodiment, the direction switching valve 70 is a so-called three-position valve, and is capable of forming a non-flow state (FIG. 1), a first flow state (FIG. 7), and a second flow state (FIG. 8). The non-flow state is a state in which the first flow path L1, the second flow path L2, the third flow path, and the fourth flow path L4 are not connected. The first flow state is a state in which the first flow path L1 and the second flow path L2 are connected, and the third flow path L3 and the fourth flow path L4 are connected. The second flow state is a state in which the first flow path L1 and the third flow path L3 are connected, and the second flow path L2 and the fourth flow path L4 are connected. The direction switching valve 70 is controlled by a controller 80.

[0025] The controller 80 is configured to include, for example, a central processing unit, a read-only memory (ROM), a random access memory (RAM), a non-volatile RAM, etc. The detection results of the first pressure sensor 41, the second pressure sensor 42, the first flow rate sensor 51, the second flow rate sensor 52, and the state quantity detection sensor 55 are input to the controller 80. Based on the input detection results, the controller 80 controls the first switching valve 21, the second switching valve 22, the first pump 31, the second pump 32, and the directional switching valve 70, and executes a grease replacement process in which a cleaning liquid, an activator, and new grease are supplied to the bearing 1.

[0026] (Grease replacement process) Next, the grease replacement process will be described. Fig. 5 is a flowchart showing the grease replacement process. The grease replacement process includes a cleaning process ST1 as a bearing cleaning method according to this embodiment, an activator injection process ST2, and a new grease injection process ST3, and the controller 80 executes each process in sequence in response to instructions from an operator. The grease replacement process is started with the second flow path L2 and the third flow path L3 connected to the bearing 1. In this embodiment, the grease replacement process is executed without rotating the inner ring 2 and outer ring 3 of the bearing 1 relative to each other. However, the grease replacement process may also be executed while rotating the inner ring 2 and outer ring 3 relative to each other.

[0027] (Cleaning process) The cleaning process ST1 is a process in which the cleaning liquid is circulated by the first pump 31 and the second pump 32 in a circulation flow path L formed between the bearing 1 and a cleaning liquid tank 11 that stores the cleaning liquid, thereby cleaning the grease inside the bearing 1. In the cleaning process ST1, the cleaning liquid is injected into the bearing 1 while switching between the first flow state and the second flow state. FIG. 6 is a flowchart showing the steps of the cleaning process ST1. FIG. 7 is an explanatory diagram showing the cleaning process ST1 in the first flow state. FIG. 8 is an explanatory diagram showing the cleaning process ST1 in the second flow state.

[0028] In step ST11, the controller 80 connects the cleaning liquid tank 11 to the circulation flow path L using the first switching valve 21 and the second switching valve 22, as shown in Fig. 7. Next, in step ST12, the controller 80 creates either the first flow state or the second flow state using the directional switching valve 70. Here, an example will be described in which the first flow state is created first.

[0029] Then, in step ST13, the controller 80 starts circulating the cleaning liquid through the circulation flow path L. Specifically, the controller 80 causes the first pump 31 to pressurize the cleaning liquid in the cleaning liquid tank 11 and supply it to the bearing 1 via the first flow path L1 and the second flow path L2. The controller 80 also causes the second pump 32 to suck the cleaning liquid containing the dissolved grease from the bearing 1 and return it to the cleaning liquid tank 11 via the third flow path L3 and the fourth flow path L4.

[0030] At this time, if the cleaning liquid continues to be pressurized and injected into the bearing 1, and the cleaning liquid and dissolved grease accumulate in part of the internal space 7, causing the pressure to increase excessively, there is a risk that the cleaning liquid and grease will leak out from between the seal member 6 and the inner ring 2 or outer ring 3. Therefore, the controller 80 determines whether there is a risk of leakage of the cleaning liquid containing dissolved grease, based on the pressure in the second flow path L2 detected by the first pressure sensor 41 and the total flow rate of the cleaning liquid supplied to the bearing 1 detected by the first flow rate sensor 51.

[0031] Specifically, in step ST14, the controller 80 determines whether the pressure P of the second flow path L2 is less than a predetermined pressure P1. If the controller 80 determines that the pressure P is less than the predetermined pressure P1 (Yes in step ST14), the controller 80 determines in step ST15 whether the total flow rate M of the cleaning liquid supplied to the bearing 1 in the current circulation state of the circulation flow path L is less than a predetermined flow rate M1. The predetermined pressure P1 and the predetermined flow rate M1 are set as values ​​just before leakage of the cleaning liquid occurs based on, for example, experiments, analysis, or machine learning based on accumulated empirical values ​​from actual equipment. If the controller 80 determines that the total flow rate M of the cleaning liquid is less than the predetermined flow rate M1 (Yes in step ST15), the controller 80 determines that there is no risk of leakage of the cleaning liquid, and proceeds to step ST17, which will be described later.

[0032] On the other hand, if the controller 80 determines that the pressure P is equal to or greater than the predetermined pressure P1 (No in step ST14) or if the controller 80 determines that the total flow rate M of the cleaning liquid is less than the predetermined flow rate M1 (No in step ST15), the controller 80 determines that there is a risk of leakage of the cleaning liquid, and proceeds to step ST16. It should be noted that just before leakage of the cleaning liquid occurs, the seal member 6 of the bearing 1 may be pushed outward, expanding the internal space 7 and causing a temporary drop in pressure within the bearing 1. For this reason, the predetermined pressure P1 may be set to a value corresponding to this drop in pressure, and the controller 80 may determine that there is a risk of leakage of the cleaning liquid when the pressure P in the second flow path L2 drops to the predetermined pressure P1.

[0033] Then, in step ST16, the controller 80 switches the flow direction of the cleaning liquid supplied to the bearing 1 using the directional switching valve 70. Here, the second flow state shown in FIG. 8 is formed. As a result, the cleaning liquid pressurized by the first pump 31 is injected into the bearing 1 from the first flow path L1 via the third flow path L3. Furthermore, the cleaning liquid in the bearing 1 sucked by the second pump 32 is returned to the cleaning liquid tank 11 from the second flow path L2 via the fourth flow path L4. This eliminates the state in which the cleaning liquid and dissolved grease are accumulated in part of the internal space 7, suppressing an increase in pressure in the internal space 7 and making it possible to suppress leakage of the cleaning liquid. After switching the flow direction of the cleaning liquid, the controller 80 proceeds to step ST17.

[0034] In step ST17, the controller 80 determines whether cleaning of the bearing 1 has been completed. The controller 80 can determine whether cleaning has been completed by estimating the amount of grease remaining inside the bearing 1 based on, for example, the degree of contamination of the cleaning liquid based on the state quantity of the cleaning liquid detected by the state quantity detection sensor 55, or the total flow rate of the cleaning liquid that has been supplied to the bearing 1 up to that point. Alternatively, the circulation flow path L or the cleaning liquid tank 11 may be provided with a portion through which the color of the cleaning liquid can be visually observed, and if an operator determines that the cleaning liquid has deteriorated based on the visually observed color, this may be input to the controller 80. Furthermore, the operator may directly observe the inside of the bearing 1 using a fiberscope or the like to determine whether cleaning has been completed.

[0035] If the controller 80 determines that cleaning of the bearing 1 has not finished (No in step ST17), it executes the processing from step ST14 onwards again. As a result, in the bearing cleaning method according to this embodiment, whenever the pressure P of the cleaning liquid supplied to the bearing 1 reaches a predetermined pressure P1 or the total flow rate M of the cleaning liquid becomes equal to or greater than a predetermined flow rate M1, the flow direction of the cleaning liquid supplied to the bearing 1 is reversed by the directional switching valve 70. As a result, leakage of the cleaning liquid from the bearing 1 can be effectively suppressed.

[0036] On the other hand, if the controller 80 determines that cleaning of the bearing 1 has been completed (Yes in step ST17), it stops the operation of the first pump 31 and the second pump 32 to stop the circulation of the cleaning liquid (step ST18), and ends the cleaning process ST1.

[0037] (Activator injection treatment) Next, the activator injection process ST2 will be described. FIG. 9 is an explanatory diagram showing the activator injection process ST2. The activator injection process ST2 is performed with the third flow path L3 disconnected from the bearing 1. As shown in the figure, the controller 80 connects the activator tank 12 to the first flow path L1 using the first switching valve 21 and establishes a first flow state using the directional switching valve 70. In this state, the controller 80 injects the activator from the activator tank 12 into the internal space 7 of the bearing 1 using the first pump 31. The controller 80 monitors the total flow rate of the activator supplied to the bearing 1 based on the detection result of the first flow sensor 51, and stops the first pump 31 when the total flow rate reaches a predetermined activator injection amount. Although not shown, most of the activator injected into the bearing 1 is then removed by suction. The suctioned activator is discharged outside the bearing cleaning device 10. This completes the activator injection process ST2.

[0038] (New grease injection treatment) Next, the new grease injection process ST3 will be described. FIG. 10 is an explanatory diagram showing the new grease injection process ST3. The new grease injection process ST3 is performed with the third flow path L3 disconnected from the bearing 1. As shown in FIG. 10, the controller 80 connects the grease tank 13 to the first flow path L1 using the first switching valve 21. In this state, the controller 80 injects new grease from the grease tank 13 into the internal space 7 of the bearing 1 using the first pump 31. The controller 80 monitors the total flow rate of new grease supplied to the bearing 1 based on the detection result of the first flow sensor 51. The controller 80 monitors the total flow rate of new grease using the first flow sensor 51. When the total flow rate reaches a predetermined new grease injection amount, the controller 80 stops the first pump 31 and ends the new grease injection process ST3. This completes the grease replacement process for the bearing 1.

[0039] (Effects of the embodiment) As described above, the bearing cleaning device 10 according to the embodiment comprises a cleaning liquid tank 11 for storing cleaning liquid, a circulation flow path L for circulating the cleaning liquid between the cleaning liquid tank 11 and the bearing 1, a pump device 30 for pressurizing the cleaning liquid within the circulation flow path L, a pressure detection device 40 for detecting the pressure of the cleaning liquid supplied to the bearing 1, a direction switching valve 70 capable of reversing the flow direction of the cleaning liquid supplied to the bearing 1 within the circulation flow path L, and a controller (control device) 80 for controlling the direction switching valve 70 to reverse the flow direction of the cleaning liquid supplied to the bearing 1 based on the pressure detected by the pressure detection device 40.

[0040] With this configuration, the direction of flow of the cleaning liquid supplied to the bearing 1 can be switched by the directional switching valve 70 based on the pressure P of the cleaning liquid supplied to the bearing 1 before leakage of the cleaning liquid from the bearing 1 occurs. As a result, even if sufficiently pressurized cleaning liquid is supplied to the bearing 1, an increase in pressure in the internal space 7 of the bearing 1 can be effectively suppressed. Therefore, the bearing cleaning device 10 according to the embodiment can more quickly clean the grease (lubricant) inside the bearing 1 while suppressing leakage of the cleaning liquid from the bearing 1. Since there is no need to replace the entire bearing 1, its lifespan can be extended and maintenance costs can be reduced.

[0041] Furthermore, when the pressure P detected by the pressure detection device 40 reaches a predetermined pressure P1, which is set as a value just before leakage of the cleaning liquid from the bearing 1 occurs, the controller 80 causes the direction switching valve 70 to reverse the flow direction of the cleaning liquid supplied to the bearing 1. With this configuration, it is possible to automatically control the direction switching valve 70 based on the pressure P and switch the flow direction of the cleaning liquid supplied to the bearing 1 before leakage of the cleaning liquid occurs.

[0042] Furthermore, the bearing cleaning device 10 is equipped with a flow rate detection device 50 that detects the flow rate of the cleaning liquid in the circulation flow path L, and when the total flow rate M of the cleaning liquid supplied to the bearing 1 detected by the flow rate detection device 50 reaches or exceeds a predetermined flow rate M1 that is set as the value just before the cleaning liquid starts to leak from the bearing 1, the controller 80 causes the directional switching valve 70 to reverse the flow direction of the cleaning liquid supplied to the bearing 1. With this configuration, it is possible to determine whether or not the cleaning liquid will leak from the bearing 1 based not only on the pressure P but also on the total flow rate M of the cleaning liquid supplied to the bearing 1, thereby making it possible to more effectively suppress the occurrence of cleaning liquid leakage.

[0043] The bearing cleaning device 10 also includes an activator tank 12 that stores an activator and is connected to the circulation flow path L, a grease tank (lubricant tank) 13 that stores a lubricant and is connected to the circulation flow path L, and a connection switching device 20 that switches the connections of the cleaning liquid tank 11, activator tank 12, and grease tank 13 to the circulation flow path L. With this configuration, the bearing cleaning device 10 can also be used to inject an activator or inject new grease into the bearing 1.

[0044] The bearing cleaning device 10 also includes a probe (connecting member) 90 that is connected to the circulation flow path L, is inserted into the bearing 1, and has communication holes 92 and 93 that communicate with the circulation flow path L, and a heating device 95 that heats the probe 90. With this configuration, the probe 90 is heated during the cleaning process ST1 to raise the temperature of the cleaning liquid, making it possible to more effectively dissolve the grease in the cleaning liquid. Note that the heating device 95 is not limited to heating the probe 90, and may also heat any location in the circulation flow path L. However, it is preferable that the heating device 95 be provided near the bearing 1. The probe 90 only needs to have at least the communication hole 92.

[0045] Although the description of the embodiment has been completed above, aspects of the present invention are not limited to this embodiment. For example, in this embodiment, in step ST16 of the cleaning process ST1, the controller 80 automatically controls the directional switching valve 70. However, the detection results of the pressure detection device 40 and the flow rate detection device 50 may be output to a monitor or the like, and an operator may monitor the detection results and instruct the controller 80 to switch the flow direction using the directional switching valve 70 based on the detection results.

[0046] Furthermore, the pump device 30 may be either one of the first pump 31 or the second pump 32, as long as it is able to generate sufficient pressure within the circulation flow path L. Furthermore, the pressure detection device 40 may be either one of the first pressure sensor 41 or the second pressure sensor 42, as long as it is able to monitor pressure changes inside the bearing 1. Furthermore, the flow rate detection device 50 may be either one of the first flow rate sensor 51 or the second flow rate sensor 52, as long as it is able to detect the total flow rate of the cleaning liquid supplied to the bearing 1.

[0047] Furthermore, in this embodiment, the controller 80 determines that there is a risk of cleaning fluid leaking from the bearing 1 when a negative determination is made in either step ST14 or step ST15. However, the controller 80 may also determine that there is a risk of cleaning fluid leaking from the bearing 1 when a negative determination is made in both step ST14 and step ST15. Also, step ST15 may be omitted. In other words, the flow rate detecting device 50 may be omitted from the bearing cleaning device 10 with regard to the execution of the cleaning process ST1. [Explanation of symbols]

[0048] 1. Bearings 10 Bearing cleaning equipment 11 Cleaning solution tank 12 Activator Tank 13 Grease tank (lubricant tank) 20 Connection switching device 30 Pumping equipment 40 Pressure detection device 50 Flow detection device 70 Directional valve 80 Controller (control device) 90 Probe (connecting member) 95 Heating device L Circulation flow path

Claims

1. A bearing cleaning device that cleans the lubricant inside a bearing with a cleaning liquid, a cleaning liquid tank that stores the cleaning liquid; a circulation flow path that circulates the cleaning liquid between the cleaning liquid tank and the bearing; a pump device that pumps the cleaning liquid through the circulation flow path; a pressure detection device that detects the pressure of the cleaning liquid supplied to the bearing; a direction switching valve capable of reversing the flow direction of the cleaning liquid supplied to the bearing within the circulation flow path; a control device that controls the direction switching valve to reverse the flow direction of the cleaning liquid supplied to the bearing based on the pressure detected by the pressure detection device; and A bearing cleaning device comprising:

2. 2. The bearing cleaning device according to claim 1, wherein the control device reverses the flow direction of the cleaning liquid supplied to the bearing by the directional switching valve when the pressure detected by the pressure detection device reaches a predetermined pressure that is set as a value just before leakage of the cleaning liquid from the bearing occurs.

3. a flow rate detection device for detecting a flow rate of the cleaning liquid in the circulation flow path; the control device reverses the flow direction of the cleaning liquid supplied to the bearing by the directional switching valve when the total flow rate of the cleaning liquid supplied to the bearing detected by the flow rate detection device becomes equal to or greater than a predetermined flow rate set as a value just before leakage of the cleaning liquid from the bearing occurs.

3. The bearing cleaning device according to claim 2.

4. an activator tank that stores an activator and is connected to the circulation flow path; a lubricant tank that stores a lubricant and is connected to the circulation flow path; a connection switching device for switching the connections of the cleaning liquid tank, the activator tank, and the lubricant tank to the circulation flow path; 4. The bearing cleaning device according to claim 1, further comprising:

5. a connecting member connected to the circulation flow path, inserted into the bearing, and having at least one or more communication holes formed therein that communicate with the circulation flow path; a heating device that heats the connection member or the circulation flow path; 4. The bearing cleaning device according to claim 1, further comprising:

6. A bearing cleaning method in which a cleaning liquid is circulated by a pump device in a circulation flow path formed between a cleaning liquid tank that stores the cleaning liquid and a bearing, thereby cleaning a lubricant inside the bearing, when the pressure of the cleaning liquid supplied to the bearing reaches a predetermined pressure that is set as a value just before leakage of the cleaning liquid from the bearing occurs, a direction switching valve disposed in the circulation flow path reverses the flow direction of the cleaning liquid supplied to the bearing. A bearing cleaning method characterized by:

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