Foreign object recognition system

Abstract

To provide a foreign object recognition system which can recognize a bulky foreign object mixed into an oil quickly and precisely.SOLUTION: A transmission 1 includes: a housing 2 including a tank 10; an oil supply passage 3 attached to the housing 2; and a visualization sensor 4. The tank 10 has: a strainer 13 disposed within a second space 12 leading to a first space 11; and a partition wall 14 disposed between the first space 11 and the second space 12 and extending from the upper side to the lower side. The visualization sensor 4 recognizes segments S1, S2 located below the partition wall 14.SELECTED DRAWING: Figure 3

Description

Technical Field

[0008] , , , , , ,

[0007]

[0001] The present disclosure relates to a foreign object recognition system.

Background Art

[0002] Conventionally, work vehicles such as bulldozers and wheel loaders are provided with a hydraulic device that supplies oil to a predetermined device (for example, a transmission, an axle, a braking device, etc.).

[0003] The hydraulic device is provided with a tank for storing oil, a strainer disposed in the tank, and a hydraulic pump for discharging the oil that has passed through the strainer.

[0004] In Patent Document 1, a method for optically recognizing foreign objects mixed in the oil discharged from a hydraulic pump has been proposed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Since the method of Patent Document 1 recognizes minute foreign objects mixed in the oil that has passed through the strainer, it cannot recognize large foreign objects separated by the strainer.

[0007] An object of the present disclosure is to provide a foreign object recognition system capable of quickly and accurately recognizing large foreign objects mixed in oil.

Means for Solving the Problems

[0008] The foreign object recognition system according to this disclosure comprises a housing including a tank for storing oil, an oil supply passage attached to the housing, and a foreign object recognition device. The tank has a first space, a second space connected to the first space, a strainer for separating foreign objects mixed in with the oil flowing from the second space to the oil supply passage, and a partition wall positioned between the first space and the second space and extending from top to bottom. The foreign object recognition device recognizes foreign objects located below the partition wall. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a foreign object recognition system that can quickly and accurately recognize coarse foreign objects mixed in oil. [Brief explanation of the drawing]

[0010] [Figure 1] Side view of a transmission according to an embodiment [Figure 2] Cross-sectional view of the tank according to the embodiment [Figure 3] Cross-sectional view of the tank according to the embodiment [Figure 4] Cross-sectional view of a tank according to modified example 1 [Figure 5] Cross-sectional view of a tank according to modified example 2 [Modes for carrying out the invention]

[0011] (Transmission 1) Figure 1 is a side view of the transmission 1 according to an embodiment. In this specification, "up" and "down" refer to "up" and "down" with respect to the vertical direction.

[0012] Transmission 1 is mounted on work vehicles such as bulldozers and wheel loaders. Transmission 1 comprises a housing 2, an oil supply passage 3, a visualization sensor 4, and an abnormality detection device 5. The housing 2, oil supply passage 3, visualization sensor 4, and abnormality detection device 5 constitute the "foreign object recognition system" according to this disclosure.

[0013] Housing 2 houses clutches (forward / reverse clutches, speed stage clutches, etc.) and shafts (input shaft, intermediate shaft, output shaft, etc.). In this embodiment, a wet multi-plate clutch having multiple clutch discs is used as the clutch. A friction material made of, for example, a non-magnetic material (paper-based material, etc.) is attached to the core plate surface of the clutch disc with an adhesive (for example, phenolic resin). The friction material is composed of multiple segments arranged in a matrix.

[0014] Oil circulates within housing 2 to supply the clutch and shaft. A tank 10 is provided at the lower end of housing 2. The oil is stored in tank 10. A hydraulic pump 20 is provided at the upper part of housing 2. While transmission 1 is in operation, the hydraulic pump 20 draws oil stored in tank 10 through the oil supply passage 3 to lubricate various parts of transmission 1. While transmission 1 is in operation, the oil that has lubricated the various parts returns to tank 10 by gravity.

[0015] The oil supply passage 3 is attached to the housing 2. The oil supply passage 3 is an oil passage for supplying oil into the housing 2. The lower end of the oil supply passage 3 is connected to the tank 10, and the upper end of the oil supply passage 3 is connected to the hydraulic pump 20. While the transmission 1 is in operation, oil is drawn in by the hydraulic pump 20 and flows through the oil supply passage 3 from bottom to top. When the operation of the transmission 1 ends, the suction by the hydraulic pump 20 stops, and the oil accumulated in the oil supply passage 3 flows down through the oil supply passage 3 from top to bottom.

[0016] The visualization sensor 4 is attached to the tank 10. In this embodiment, the visualization sensor 4 is inserted into an insertion hole 10a formed in the outer wall of the tank 10.

[0017] The visualization sensor 4 is an example of the "foreign object recognition device" according to the present disclosure. The visualization sensor 4 recognizes foreign objects mixed in the oil stored in the tank 10. Specifically, the visualization sensor 4 images the foreign objects mixed in the oil to generate imaging data, and transmits the imaging data to the abnormality determination device 5. The configuration of the visualization sensor 4 will be described later.

[0018] The abnormality determination device 5 is connected to the visualization sensor 4. The abnormality determination device 5 acquires imaging data from the visualization sensor 4. The abnormality determination device 5 estimates the size of the foreign object recognized by the visualization sensor 4 based on the imaging data. The abnormality determination device 5 determines whether an abnormal amount of moisture is mixed in the oil based on the size of the foreign object. When the size of the foreign object is equal to or greater than the threshold value, the abnormality determination device 5 determines that an abnormal amount of moisture is mixed in the oil.

[0019] Here, when a large amount of moisture is mixed in the oil, the adhesive on the surface of the core plate of the clutch disk is decomposed and the friction material peels off segment by segment. Therefore, by setting the threshold value according to the size of the segment, it is possible to determine whether an abnormal amount of moisture is mixed in the oil.

[0020] (Tank 10) FIG. 2 and FIG. 3 are cross-sectional views of the tank 10 cut along a vertical plane. FIG. 2 shows the state during the operation of the transmission 1, and FIG. 3 shows the state after the operation of the transmission 1 ends. In FIGS. 2 and 3, the oil circulation direction is indicated by a broken line.

[0021] The tank 10 has a first space 11, a second space 12, a strainer 13, a partition wall 14, and a mesh member 15.

[0022] As shown in FIG. 2, during the operation of the transmission 1, oil flows into the first space 11 from above. The oil that has flowed into the first space 11 flows into the second space 12. Oil is stored in the first space 11.

[0023] The second space 12 is connected to the first space 11. In the direction of oil circulation, the second space 12 is located downstream of the first space 11. The second space 12 is a space designed to suppress oil aeration. The volume of the second space 12 is smaller than the volume of the first space 11. Regardless of whether the transmission 1 is running or not, the second space 12 is always filled with oil. Therefore, as shown in Figures 2 and 3, the upper surface 12T of the second space 12 is always below the oil level.

[0024] As shown in Figure 2, while the transmission 1 is in operation, the oil that lubricates each part flows into the first space 11 by gravity. The oil that flows from the first space 11 through the mesh member 15 into the second space 12 flows into the strainer 13.

[0025] The strainer 13 separates foreign matter mixed in with the oil flowing from the second space 12 to the oil supply passage 3. In this embodiment, the strainer 13 is located in the second space 12. The strainer 13 is inserted into an insertion hole 10b formed in the outer wall of the tank 10. As shown in Figure 2, during the operation of the transmission 1, the oil in the second space 12 flows through the strainer 13 to the oil supply passage 3. The strainer 13 has a filter material 16 for filtering out coarse foreign matter mixed in with the oil. The filter material 16 can be made of filter paper (e.g., nonwoven fabric) or a metal mesh. The filter material 16 may be folded. The filter material 16 separates coarse foreign matter mixed in with the oil from the oil. Here, Figure 2 illustrates how two segments S1 and S2, detached from the clutch disc, are separated by the strainer 13. Segments S1 and S2 are examples of "foreign matter" according to this disclosure. Because the surface area of ​​the strainer 13 is large, it is difficult to recognize segments S1 and S2 while they are attached to the strainer 13. Therefore, in this embodiment, as will be described later, segments S1 and S2 are recognized while they are separated from the strainer 13.

[0026] The partition wall 14 is provided inside the tank 10. The partition wall 14 is positioned between the first space 11 and the second space 12. The partition wall 14 extends from top to bottom. The lower end of the partition wall 14 is separated from the bottom surface 10T of the tank 10. Thus, the partition wall 14 is a wall that separates the first space 11 and the second space 12, but the first space 11 and the second space 12 are connected to each other through the space below the partition wall 14. The boundary between the first space 11 and the second space 12 can be defined by an extension plane that extends vertically downward from the lower end of the partition wall 14.

[0027] The mesh member 15 is positioned below the partition wall 14. In this embodiment, the upper end of the mesh member 15 is connected to the lower end of the partition wall 14, and the lower end of the mesh member 15 is connected to the bottom surface 10T.

[0028] The mesh member 15 has a mesh (holes). The mesh member 15 can be made of metal mesh, perforated metal, or other materials. The mesh size is such that segments S1 and S2, separated from the clutch disc, can pass through with the oil flow. Therefore, it is possible to prevent segments S1 and S2 from getting stuck in the mesh of the mesh member 15, which could cause poor suction by the hydraulic pump 20.

[0029] As shown in Figure 2, during the operation of transmission 1, segments S1 and S2 pass through the mesh member 15 from the first space 11 to the second space 12, carried by the oil flow. As shown in Figure 3, after the operation of transmission 1 ends, the oil in the oil supply passage 3 returns from the second space 12 to the first space 11 via the mesh member 15, but the oil flow (flow velocity) at this time is much slower than the oil flow (flow velocity) during operation. Therefore, segments S1 and S2 get caught in the mesh of the mesh member 15 and settle on the bottom surface 10T, or get caught in the mesh of the mesh member 15. As a result, segments S1 and S2 are located in a narrow area on the strainer 13 side of the mesh member 15. Since the area in which segments S1 and S2 are located is narrower than the surface area of ​​the strainer 13, segments S1 and S2 are easily recognized by the visualization sensor 4, which will be described later.

[0030] Furthermore, since foreign objects smaller than segments S1 and S2 pass through the mesh member 15 and move to the first space 11, only coarse foreign objects that may indicate damage to the transmission 1 accumulate on the strainer 13 side of the mesh member 15. Therefore, as will be described later, coarse foreign objects that may indicate damage to the transmission 1 can be recognized with high accuracy.

[0031] Here, the visualization sensor 4 is positioned to recognize the strainer 13 side of the mesh member 15. In this embodiment, the visualization sensor 4 is positioned on the strainer 13 side of the mesh member 15, but it may also be positioned on the opposite side of the mesh member 15 from the strainer 13. Even if the visualization sensor 4 is positioned on the opposite side of the mesh member 15 from the strainer 13, the visualization sensor 4 can still recognize the segment S1 caught in the mesh of the mesh member 15.

[0032] The visualization sensor 4 includes an imaging device 41 and a lighting fixture 42. The imaging device 41 images segments S1 and S2 located on the strainer 13 side of the mesh member 15. The imaging range of the imaging device 41 is set to include the surface of the mesh member 15 on the strainer 13 side and the area of ​​the bottom surface 10T on the strainer 13 side of the mesh member 15. The lighting fixture 42 illuminates the imaging range of the imaging device 41.

[0033] In this way, the visualization sensor 4 recognizes segments S1 and S2 located below the partition wall 14. Specifically, the visualization sensor 4 recognizes segments S1 and S2 located on the strainer 13 side of the mesh member 15. Therefore, even if only a small amount of coarse foreign matter is separated by the strainer 13, it can be detected early using a sensor with a limited recognition range, such as the visualization sensor. Thus, coarse foreign matter that may indicate damage to the transmission 1 can be detected quickly and accurately. As a result, as described above, the abnormality determination device 5 can quickly and accurately determine whether or not an abnormal amount of moisture is mixed in the oil.

[0034] (Modified examples of the embodiment) The present invention is not limited to the embodiments described above, and various modifications or alterations are possible without departing from the scope of the present invention.

[0035] [Example 1] In the above embodiment, the upper end of the mesh member 15 is connected to the lower end of the partition wall 14, but as shown in Figure 4, it may be separated from the lower end of the partition wall 14.

[0036] [Differentiation 2] In the above embodiment, the tank 10 is provided with a mesh member 15, but it is not necessary for the tank 10 to have a mesh member 15. Even if the tank 10 does not have a mesh member 15, foreign objects can be recognized by appropriately setting the imaging range of the visualization sensor 4.

[0037] If the tank 10 does not have a mesh member 15, it is preferable that the tank 10 further has a sedimentation wall 17 extending upward from the bottom surface 10T, as shown in Figure 5. After the operation of the transmission 1 is finished, foreign matter S mixed in with the oil returning from the second space 12 to the first space 11 can be retained by the sedimentation wall 17. Since the foreign matter S cannot pass over the sedimentation wall 17 and settles on the bottom surface 10T, the foreign matter S located on the strainer 13 side of the sedimentation wall 17 can be recognized by the visualization sensor 4.

[0038] [Difference 3] In the above embodiment, a visualization sensor 4 is used as the foreign object recognition device, but the device is not limited to this. Any non-contact sensor capable of recognizing foreign objects can be used as the foreign object recognition device. As non-contact sensors, not only the visualization sensor 4, which can capture foreign objects as an image, but also sensors that can recognize foreign objects based on the refractive index of light (for example, fiber sensors, photoelectric sensors, etc.) can be used.

[0039] [Differentiation Example 4] In the above embodiment, the strainer 13 is located in the second space 12 of the tank 10, but it may also be built into the oil supply passage 3.

[0040] [Difference 5] In the above embodiment, the case in which the foreign object recognition system according to this disclosure is applied to a transmission was described, but the foreign object recognition system according to this disclosure can also be applied to axle devices, brake devices, and the like, in addition to transmissions. The foreign object recognition system only needs to include at least a housing, an oil supply passage, and a foreign object recognition device.

[0041] (Note 1) A foreign object recognition system comprising a housing including a tank for storing oil, an oil supply passage attached to the housing, and a foreign object recognition device, wherein the tank has a first space, a second space connected to the first space, a strainer for separating foreign objects mixed in the oil flowing from the second space to the oil supply passage, and a partition wall disposed between the first space and the second space and extending from above downward, and the foreign object recognition device recognizes the foreign object located below the partition wall.

[0042] (Note 2) The foreign object recognition system according to Appendix 1, wherein the tank further comprises a mesh member positioned below the partition wall, and the foreign object recognition device recognizes the strainer side of the mesh member.

[0043] (Note 3) The foreign object recognition system according to Appendix 1, wherein the tank further has a sedimentation wall extending upward from the bottom surface, and the foreign object recognition device recognizes foreign objects located on the strainer side of the sedimentation wall.

[0044] (Note 4) The foreign object recognition device is a sensor that recognizes foreign objects, as described in any one of the appendices 1 to 3.

[0045] (Note 5) The housing is a foreign object recognition system according to any one of the appendices 1 to 4, which houses the clutch disc to which the oil is supplied.

[0046] (Note 6) The foreign object recognition system described in Appendix 5, wherein the friction material of the clutch disc is made of a non-magnetic material.

[0047] (Note 7) The foreign object recognition system according to Appendix 5 or Appendix 6, further comprising an abnormality determination device connected to the foreign object recognition device, wherein the abnormality determination device determines whether or not an abnormal amount of water is mixed into the oil based on the size of the foreign object recognized by the foreign object recognition device.

[0048] (Note 8) The foreign object recognition system described in any one of the appendices 1 to 7, wherein the volume of the second space is smaller than the volume of the first space.

[0049] (Note 9) The foreign object recognition system according to any one of the appendices 1 to 8, wherein the upper surface of the second space is always located below the liquid level of the oil. [Explanation of Symbols]

[0050] 1. Transmission 2 Housing 3. Oil supply channel 4. Visualization Sensors 4a Imaging device 4b Lighting fixtures 5 Abnormality determination device 10 tanks 10T bottom 11 1st space 12 Second space 13 Strainer 14 Partition Wall 15 Mesh member 16 Filter media 17 Sedimentation wall 20 Hydraulic pumps S1, S2 Clutch Disc Segments

Claims

1. A housing including a tank for storing oil, An oil supply passage attached to the housing, Foreign object recognition device, Equipped with, The aforementioned tank is The first space and, A second space connected to the first space, A strainer for separating foreign matter mixed in with the oil flowing from the second space to the oil supply passage, A partition wall is positioned between the first space and the second space and extends from top to bottom, It has, The foreign object recognition device recognizes the foreign object located away from the strainer and below the partition wall. Foreign object detection system.

2. A housing including a tank for storing oil, An oil supply passage attached to the housing, Foreign object recognition device, Equipped with, The aforementioned tank is The first space and, A second space connected to the first space, A strainer for separating foreign matter mixed in with the oil flowing from the second space to the oil supply passage, A partition wall is positioned between the first space and the second space and extends from top to bottom, A mesh member positioned below the partition wall, It has, The foreign object recognition device recognizes the foreign object located below the partition wall on the strainer side of the mesh member. Foreign object detection system.

3. A housing including a tank for storing oil, An oil supply passage attached to the housing, Foreign object recognition device, Equipped with, The aforementioned tank is The first space and, A second space connected to the first space, A strainer for separating foreign matter mixed in with the oil flowing from the second space to the oil supply passage, A partition wall is positioned between the first space and the second space and extends from top to bottom, A sedimentation wall extending upward from the bottom, It has, The foreign object recognition device recognizes the foreign object located below the partition wall on the strainer side of the sedimentation wall. Foreign object detection system.

4. A housing including a tank for storing oil, An oil supply passage attached to the housing, Foreign object recognition device, An abnormality determination device connected to the foreign object recognition device, Equipped with, The aforementioned tank is The first space and, A second space connected to the first space, A strainer for separating foreign matter mixed in with the oil flowing from the second space to the oil supply passage, A partition wall is positioned between the first space and the second space and extends from top to bottom, It has, The housing accommodates the clutch disc to which the oil is supplied, The foreign object recognition device recognizes the foreign object located below the partition wall, The abnormality detection device determines whether or not an abnormal amount of water is mixed into the oil based on the size of the foreign object recognized by the foreign object recognition device. Foreign object detection system.

5. The friction material of the clutch disc is made of a non-magnetic material. The foreign object recognition system according to claim 4.

6. The foreign object recognition device is a sensor that recognizes foreign objects. A foreign object recognition system according to any one of claims 1 to 4.

7. The volume of the second space is smaller than the volume of the first space. A foreign object recognition system according to any one of claims 1 to 4.

8. The upper surface of the second space is always located below the liquid level of the oil. A foreign object recognition system according to any one of claims 1 to 4.

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