Thrust wheel and working machine

Abstract

The invention relates to the technical field of engineering machinery, and discloses a thrust wheel and an operation machine. The wheel body is sleeved on the wheel shaft; the number of the end covers is two, and the two end covers are both fixed to the wheel shaft and arranged on the two opposite sides of the wheel body in the axial direction. The bearing is connected between the wheel shaft and the wheel body, and part of the bearing extends to the position between the wheel body and the end cover; wherein a thrust surface is formed on the surface, facing the bearing in the axial direction, of the end cover, a containing hole is formed in the thrust surface of the end cover, and the containing hole is filled with a solid lubricant. When the thrust surface of the end cover is in contact friction with one surface, facing the thrust surface, of the bearing, the solid lubricant is pressed to generate grease on the surface, so that the friction coefficient of the contact surface is reduced, the friction heating value between the end cover and the bearing is reduced, the oil leakage risk of the thrust wheel is reduced, and the reliability of the thrust wheel is improved.

Description

Technical Field

[0001] This invention relates to the field of engineering machinery technology, specifically to track rollers and operating machinery. Background Technology

[0002] Track rollers are core components of the running gear of tracked construction machinery such as excavators, bulldozers, and tanks. On one hand, they bear most of the vehicle's weight and transfer the load to the ground via the tracks, ensuring stable movement in complex terrain and preventing localized sinking due to concentrated loads. On the other hand, track rollers also help the tracks maintain their correct trajectory, preventing lateral deviation or slippage. Simultaneously, track rollers work in conjunction with drive sprockets and guide sprockets to ensure smooth and orderly cyclical operation of the tracks.

[0003] A track roller typically consists of an axle, a wheel body mounted on the axle, bearings connecting the axle and wheel body, and end caps fixed at both ends of the axle to axially limit the wheel body. Lubricating oil is injected inside the track roller to reduce friction and wear between the end caps and bearings, and between the axle and bearings, and to reduce heat generation. However, during prolonged operation, especially under lateral loads, the end caps on the loaded side often fail to form an effective oil film with the bearings as they slide under lateral loads. This leads to significant heat generation from friction, causing oil leaks and other problems that affect the track roller's reliability. Summary of the Invention

[0004] This invention provides a track roller and operating machinery to solve the problem in the prior art where the end cap often fails to form an effective oil film when sliding with the bearing under lateral load, resulting in a large amount of heat generated by friction, causing oil leakage in the track roller, and affecting the reliability of the track roller.

[0005] In a first aspect, the present invention provides a support roller, comprising:

[0006] axle; The wheel body is fitted onto the axle; Two end caps are provided, each of which is fixed to the axle and is axially disposed on opposite sides of the wheel body. A bearing, connected between the axle and the wheel body, with a portion of the bearing extending between the wheel body and the end cap; The end cap has a thrust surface on the side facing the bearing along the axial direction, and the end cap has a receiving hole on the thrust surface, which is filled with solid lubricant.

[0007] Beneficial effects: By opening a receiving hole in the thrust surface of the end cap and filling the receiving hole with solid lubricant, when the thrust surface of the end cap and the side of the bearing facing the thrust surface come into contact and rub against each other, the solid lubricant will generate grease on the surface due to pressure, reducing the friction coefficient of the contact surface, thereby reducing the frictional heat generation between the end cap and the bearing, reducing the risk of oil leakage of the track roller, and improving the reliability of the track roller.

[0008] In one alternative embodiment, the thrust surface is formed with a wear-resistant layer.

[0009] Beneficial effects: By forming a wear-resistant layer on the thrust surface, the wear resistance of the thrust surface is improved, effectively reducing the wear risk of the end cap and extending the service life of the end cap.

[0010] In one alternative embodiment, the hardness of the wear-resistant layer is 42HRC-60HRC.

[0011] In one alternative embodiment, the roughness Ra of the thrust surface is ≤0.8 μm.

[0012] Beneficial effects: It makes the thrust surface have a lower roughness, which can effectively reduce the friction coefficient between the end cap and the bearing, thereby further reducing the temperature rise rate when the end cap and the bearing rub against each other, reducing the risk of oil leakage caused by high temperature, and further improving the reliability of the track roller.

[0013] In one alternative embodiment, the depth of the receiving hole along the axial direction is h, satisfying 5mm≤h≤6mm.

[0014] Beneficial effect: While ensuring the amount of solid lubricant that the receiving hole can hold, it avoids affecting the structural strength of the end cap.

[0015] In one alternative embodiment, the solid lubricant has a portion protruding beyond the receiving hole.

[0016] Beneficial effect: When the thrust surface and the bearing side facing the thrust surface come into contact, it facilitates the rapid lubrication of the solid lubricant between the two contact surfaces.

[0017] In one alternative embodiment, a plurality of receiving holes are spaced apart circumferentially along the thrust surface.

[0018] Beneficial effects: It facilitates the provision of solid lubricant at different positions when the thrust surface and the bearing face towards the thrust surface are in contact, reducing the risk of friction between the end cap and the bearing.

[0019] In one alternative embodiment, the distance between the thrust surface and the side of the bearing facing the thrust surface along the axial direction is 'a', satisfying 0.3mm ≤ a ≤ 0.6mm.

[0020] Beneficial effect: When the support roller is in normal upright walking state, the end cap and bearing do not come into contact, avoiding friction between the two.

[0021] In one optional embodiment, the end cap is axially aligned with one end of the wheel body to form a floating seal chamber, and a floating oil seal is provided in the floating seal chamber, the floating oil seal surrounding the outer periphery of the thrust surface.

[0022] Beneficial effects: When the thrust surface of the end cap and the side of the bearing facing the thrust surface come into contact and rub against each other, the solid lubricant will generate grease on the surface due to pressure, which reduces the friction coefficient of the contact surface, thereby reducing the frictional heat between the end cap and the bearing, and thus reducing the risk of oil leakage failure of the floating oil seal due to high temperature.

[0023] Secondly, the present invention also provides a working machine, including the aforementioned support roller. Attached Figure Description

[0024] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the overall structure of a support roller according to an embodiment of the present invention; Figure 2 for Figure 1 A top view of the support roller shown; Figure 3 for Figure 2 A cross-sectional view along the AA direction; Figure 4 for Figure 3 A magnified view of part B in the diagram; Figure 5 This is a schematic diagram of the end cap structure according to an embodiment of the present invention; Figure 6 for Figure 5 The side view of the end cap shown.

[0026] Explanation of reference numerals in the attached figures: 1. Axle; 2. Wheel body; 3. End cap; 31. Thrust surface; 32. Receiving hole; 4. Bearing; 5. Solid lubricant; 6. Floating oil seal; 7. Fixed pin; 8. Sealing ring. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Track rollers are the core components of the running gear of tracked construction machinery. They need to bear the weight of the entire machine and the operating load for a long time, and the working environment is usually very harsh, resulting in a high failure rate. Key components such as bearings and floating oil seals inside are very sensitive to high temperatures and impurities. Under the combined effect of high temperatures and impurities, they are prone to failure, which in turn leads to oil leakage problems.

[0029] Specifically, the track roller's wheel body, axle, and end cap form a sealed cavity filled with lubricating grease. In this structure, when the track roller is subjected to lateral forces, the inner end face of the end cap comes into contact with the bearing end face, and they rotate relative to each other under the drive of the track, often making it difficult to form a stable and effective oil film. The sliding friction between the bearing and the end cap generates a large amount of heat, causing the internal temperature of the wheel body to rise. When the temperature exceeds the tolerance range of the floating oil seal, the floating oil seal will harden and lose its elasticity, directly leading to oil leakage from the wheel body.

[0030] Furthermore, metal shavings generated by the sliding friction between the bearing and the end cover can mix into the lubricating grease, causing lubricant contamination. At the same time, excessive wear of the end cover will increase the axial movement of the wheel body. Once this exceeds the elastic compensation capacity of the floating oil seal, gaps will appear on the oil seal mating surfaces, ultimately leading to oil leakage.

[0031] The following is combined with Figures 1 to 6 The following describes embodiments of the present invention.

[0032] According to an embodiment of the present invention, in one aspect, a support roller is provided, comprising: Wheel and axle 1; Wheel body 2 is fitted onto wheel axle 1; There are two end caps 3, both of which are fixed to the axle 1 and are respectively located on opposite sides of the wheel body 2 along the axial direction; Bearing 4 is connected between axle 1 and wheel body 2, and part of bearing 4 extends between wheel body 2 and end cap 3; Among them, the side of the end cap 3 facing the bearing 4 along the axial direction forms a thrust surface 31, and the end cap 3 has a receiving hole 32 on the thrust surface 31, which is filled with solid lubricant 5.

[0033] In this embodiment, the support roller has a receiving hole 32 at the thrust surface 31 of the end cap 3, and a solid lubricant 5 is filled in the receiving hole 32. When the thrust surface 31 of the end cap 3 and the side of the bearing 4 facing the thrust surface 31 come into contact and rub against each other, the solid lubricant 5 will generate grease on the surface due to pressure, which reduces the friction coefficient of the contact surface, thereby reducing the frictional heat between the end cap 3 and the bearing 4, reducing the risk of oil leakage of the support roller, and improving the reliability of the support roller.

[0034] In addition, it can reduce the wear between the end cap 3 and the bearing 4, which can not only reduce the risk of metal impurities, thereby reducing the contamination of lubricating grease, but also ensure reliable positioning of the wheel body 2 and reduce the risk of oil leakage. In this way, the service life of the support roller can be extended.

[0035] It is worth noting that, such as Figure 3 As shown, the wheel body 2 is rotatably mounted in the middle position of the wheel axle 1 via the bearing 4. Specifically, the bearing 4 is usually a sliding bearing. The inner ring (i.e., journal) of the bearing 4 is sleeved on the wheel axle 1 and fixedly connected to the wheel axle 1. The bushing of the bearing 4 is fixed inside the wheel body 2 (specifically, it can be an interference fit), thereby realizing the relative rotation between the wheel body 2 and the wheel axle 1.

[0036] Specifically, such as Figure 3 As shown, there are usually two bearings 4, which are located near the opposite ends of the wheel body 2 along the axial direction.

[0037] It should be noted that, in this embodiment, as Figure 3 As shown, the bearing 4 includes a portion radially connected between the axle 1 and the wheel body 2, and a portion axially located between the wheel body 2 and the end cover 3. Furthermore, a gap is provided between the end cover 3 and the wheel body 2 axially to prevent sliding friction between the wheel body 2 and the end cover 3 when the wheel body 2 rotates.

[0038] It is worth noting that, such as Figure 3 As shown, in this embodiment, "axial direction" refers to the axial direction of the axle 1, which is also the axial direction of the wheel body 2 and the end cap 3. That is, the axle 1, wheel body 2, and two end caps 3 are all coaxially arranged.

[0039] Specifically, in one embodiment, such as Figures 1 to 3 As shown, the end cap 3 is fitted onto the axle 1 and is fixedly connected to the axle 1 by a fixing pin 7, that is, the positions of the end cap 3 and the axle 1 are relatively fixed. When the wheel 2 rotates, the wheel 2 rotates relative to the end cap 3.

[0040] Specifically, in one embodiment, the solid lubricant 5 is made of a high-molecular polymer material with a porous microporous structure. It can adsorb and store lubricating oil through the micropores, forming an oil-containing self-lubricating material. During operation, the solid lubricant 5, relying on the oil-storing characteristics of its micropores, can release the stored lubricating oil under the pressure of the friction pair and the influence of operating temperature rise, forming a stable and effective lubricating film at the friction interface, thereby achieving a long-lasting self-lubricating effect.

[0041] Of course, as an alternative implementation, the solid lubricant 5 may also include other self-lubricating solid materials known in the art, including but not limited to: molybdenum disulfide, graphite, boron nitride, polytetrafluoroethylene, carbon fiber reinforced polymers, metal-based self-lubricating composite materials, bronze-graphite sintered materials, etc. The above-mentioned solid lubricants 5 can be used alone or in combination in different proportions to meet the long-term lubrication requirements under harsh working conditions such as heavy loads, low speeds, high temperatures, and high levels of impurities.

[0042] Furthermore, in one embodiment, the thrust surface 31 is formed with a wear-resistant layer. By forming a wear-resistant layer on the thrust surface 31, the wear resistance of the thrust surface 31 is improved, effectively reducing the wear risk of the end cap 3 and extending the service life of the end cap 3.

[0043] It should be noted that by setting a wear-resistant layer, the wear risk of the thrust surface 31 of the end cap 3 can be effectively reduced. This not only effectively reduces the formation of metal impurities, but also ensures the reliable axial positioning of the wheel body 2 and reduces the risk of oil leakage.

[0044] It is worth noting that the surface hardness of the thrust surface 31 of the end cap 3 can be improved by quenching the surface of the thrust surface 31 of the end cap 3, thereby enhancing the wear resistance of the thrust surface 31 of the end cap 3.

[0045] Specifically, in one embodiment, the hardness of the wear-resistant layer is 42HRC-60HRC.

[0046] It is worth noting that HRC (Rockwell Hardness Scale C) is the hardness designation of the Rockwell hardness C scale. It is measured using a diamond cone indenter and is mainly applicable to quenched steel, bearing steel, structural steel, and various high-hardness metal components that have been strengthened by heat treatment. It is an important indicator for characterizing the wear resistance and mechanical strength of materials.

[0047] Optionally, the hardness of the wear-resistant layer is any value of 42HRC, 45HRC, 48HRC, 50HRC, 52HRC, 55HRC, 58HRC, or 60HRC, or a value between any two of these values.

[0048] Furthermore, in one embodiment, the roughness Ra of the thrust surface 31 is ≤0.8μm. This setting allows the thrust surface 31 to have a low roughness, which can effectively reduce the coefficient of friction between the end cap 3 and the bearing 4, thereby further reducing the rate of temperature rise during friction between the end cap 3 and the bearing 4, reducing the risk of oil leakage caused by high temperature, and further improving the reliability of the support roller.

[0049] It is worth noting that after the thrust surface 31 of the end face is quenched, the surface of the thrust surface 31 is then ground, which can improve the surface hardness of the thrust surface 31 and reduce the surface roughness.

[0050] It should be noted that Ra (arithmetic mean deviation of the profile) is the most core and commonly used parameter for measuring the micro-roughness of a surface, and its unit is micrometer (μm). The smaller the value of Ra, the smoother the surface; the larger the value of Ra, the rougher the surface. Roughness Ra can be measured using methods such as: stylus method: a diamond stylus is traversed across the surface to measure displacement → electrical signal → Ra calculation; optical method: laser interferometry, confocal microscopy, non-contact, high-precision; comparative method: visual / tactile comparison with a standard roughness sample.

[0051] Optionally, the roughness Ra can be any value among 0.1μm, 0.2μm, 0.3μm, 0.4μm, 0.5μm, 0.6μm, 0.7μm, and 0.8μm, or a value between any two values. Of course, it can also be a value less than 0.1μm.

[0052] In one embodiment, such as Figure 4 As shown, the depth of the receiving hole 32 along the axial direction is h, satisfying 5mm≤h≤6mm. This setting ensures that the receiving hole 32 can accommodate the amount of solid lubricant 5 while avoiding affecting the structural strength of the end cap 3.

[0053] It is worth noting that if the value of h is too small, the volume of the receiving hole 32 may be too small, resulting in a small volume of solid lubricant 5 that the receiving hole 32 can hold, which will affect the lubrication effect when the thrust surface 31 and the side of the bearing 4 facing the thrust surface 31 come into contact. If the value of h is too large, the opening of the receiving hole 32 may weaken the structural strength of the end cover 3 too much, increasing the risk of damage and cracking of the end cover 3 during the use of the support roller, thus affecting the reliability and service life of the support roller.

[0054] Optionally, the depth h of the receiving hole 32 can be any value among 5mm, 5.1mm, 5.2mm, 5.3mm, 5.4mm, 5.5mm, 5.6mm, 5.7mm, 5.8mm, 5.9mm, and 6mm, or a value between any two of these values.

[0055] Optionally, in one embodiment, the opening diameter of the receiving hole 32 is 8 mm radially. Of course, the opening diameter of the receiving hole 32 can be specifically set according to actual needs.

[0056] It is worth noting that, such as Figure 3 As shown, in this embodiment, "radial" refers to the direction perpendicular to "axial".

[0057] Furthermore, in one embodiment, such as Figure 4 As shown, the solid lubricant 5 protrudes partially beyond the receiving hole 32. This arrangement facilitates rapid lubrication between the contact surfaces of the solid lubricant 5 when the thrust surface 31 and the side of the bearing 4 facing the thrust surface 31 come into contact.

[0058] Understandably, along the axial direction, the height of the solid lubricant 5 is greater than the depth of the receiving hole 32.

[0059] Optionally, in one embodiment, the solid lubricant 5 protrudes 0.1 mm from the receiving hole 32 along the axial direction; that is, the height of the solid lubricant 5 is 0.1 mm greater than the depth of the receiving hole 32 along the axial direction. Of course, the height of the solid lubricant 5 protruding from the receiving hole 32 can be specifically set according to actual needs.

[0060] It is worth noting that, along the radial direction, the diameter of the solid lubricant 5 is consistent with the opening diameter of the receiving hole 32, that is, the solid lubricant 5 completely fills the interior of the receiving hole 32.

[0061] Furthermore, in one embodiment, such as Figure 5 and Figure 6 As shown, several receiving holes 32 are spaced apart circumferentially along the thrust surface 31. This arrangement ensures that solid lubricant 5 can be provided when the thrust surface 31 and the side of the bearing 4 facing the thrust surface 31 are in contact at different positions, reducing the risk of friction between the end cap 3 and the bearing 4.

[0062] Specifically, in one embodiment, a plurality of receiving holes 32 are evenly spaced along the circumference of the thrust surface 31.

[0063] Optionally, the number of receiving holes 32 along the circumference of the thrust surface 31 can be 20, 30, or other numbers, depending on actual needs.

[0064] In one embodiment, such as Figure 4 As shown, along the axial direction, the distance between the thrust surface 31 and the side of the bearing 4 facing the thrust surface 31 is 'a', satisfying 0.3mm≤a≤0.6mm. With this setting, the end cap 3 and the bearing 4 do not come into contact when the support roller is in normal upright walking state, avoiding friction between them.

[0065] It is worth noting that if the value of 'a' is too small, the distance between the thrust surface 31 and the side of the bearing 4 facing the thrust surface 31 will be too close, increasing the risk of contact between the thrust surface 31 and the side of the bearing 4 facing the thrust surface 31, which may easily cause friction between the end cover 3 and the bearing 4. If the value of 'a' is too large, it may increase the axial space occupied by the support roller as a whole, affecting the compactness of the support roller layout.

[0066] Optionally, the distance 'a' between the thrust surface 31 and the side of the bearing 4 facing the thrust surface 31 can be any value among 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, and 0.6mm, or a value between any two of these values.

[0067] It should be noted that when the track roller 2 is subjected to lateral load from the track, the thrust surface 31 will come into contact with the side of the bearing 4 facing the thrust surface 31, and sliding friction will occur during the operation of the track roller 2. At this time, the solid lubricant 5 will be compressed to produce grease, which will reduce the coefficient of friction between the thrust surface 31 and the side of the bearing 4 facing the thrust surface 31, thereby reducing frictional heat generation, slowing down the temperature rise rate, and avoiding high temperature and increased risk of oil leakage.

[0068] In one embodiment, such as Figure 3 As shown, the end cap 3 is axially aligned with the wheel body 2 and forms a floating seal chamber with the wheel body 2. A floating oil seal 6 is provided in the floating seal chamber and surrounds the outer periphery of the thrust surface 31.

[0069] It is worth noting that when the thrust surface 31 of the end cover 3 and the side of the bearing 4 facing the thrust surface 31 come into contact and rub against each other, the solid lubricant 5 will generate grease on the surface due to pressure, which reduces the friction coefficient of the contact surface, thereby reducing the frictional heat between the end cover 3 and the bearing 4, and thus reducing the risk of oil leakage failure of the floating oil seal 6 due to high temperature.

[0070] It is worth noting that the Floating Oil Seal 6 is a face mechanical seal specifically designed for extreme and harsh working conditions such as low speed, heavy load, dust, and mud. Its core relies on the sealing of a pair of precision-ground metal rings with their end faces fitting together. A rubber ring provides clamping force and floating compensation, making it a key sealing component of the traveling mechanism of engineering machinery. A complete Floating Oil Seal 6 consists of two floating seal rings, two O-rings, and two floating seal seats. In a static state, the elasticity of the O-rings ensures a tight fit between the end faces of the two floating seal rings, preventing oil leakage and mud intrusion. In a dynamic state, one ring rotates while the other remains stationary, forming an extremely thin oil film between the end faces. Furthermore, the elasticity of the O-rings allows the floating seal rings to float axially, automatically compensating for end face wear and extending their service life. It also allows for radial floating, adapting to shaft eccentricity, vibration, and installation errors, ensuring the sealing surfaces are always aligned and in contact.

[0071] Furthermore, in one embodiment, such as Figure 3 As shown, a sealing ring 8 (e.g., an O-ring) is provided between the outer circumferential surface of the wheel axle 1 and the inner circumferential surface of the end cover 3 that mates with it, thereby forming a sealed cavity between the wheel body 2, the wheel axle 1 and the end cover 3 for filling with lubricating grease.

[0072] It should be noted that the end cap design of the track roller in this embodiment is simple in structure, easy to assemble, and low in cost, and can be widely used in different models of track roller products.

[0073] According to an embodiment of the present invention, another aspect provides a working machine including the aforementioned support roller.

[0074] It's worth noting that the operating machinery can include construction equipment such as excavators, bulldozers, and crawler cranes. Of course, it can also include other equipment with track rollers, such as tanks.

[0075] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A support roller, characterized in that, include: Wheel and axle (1); Wheel body (2) is fitted onto the wheel axle (1); Two end caps (3) are provided, and both end caps (3) are fixed to the axle (1) and are respectively disposed on opposite sides of the wheel body (2) along the axial direction; A bearing (4) is connected between the axle (1) and the wheel body (2), and a portion of the bearing (4) extends between the wheel body (2) and the end cap (3); The end cap (3) forms a thrust surface (31) on the side facing the bearing (4) along the axial direction. The end cap (3) has a receiving hole (32) on the thrust surface (31), and the receiving hole (32) is filled with solid lubricant (5).

2. The support roller according to claim 1, characterized in that, The thrust surface (31) has a wear-resistant layer.

3. The support roller according to claim 1, characterized in that, The hardness of the wear-resistant layer is 42HRC-60HRC.

4. The support roller according to claim 1, characterized in that, The roughness Ra of the thrust surface (31) is ≤0.8μm.

5. The support roller according to claim 1, characterized in that, Along the axial direction, the depth of the receiving hole (32) is h, which satisfies 5mm≤h≤6mm.

6. The support roller according to claim 1, characterized in that, The solid lubricant (5) has a portion protruding beyond the receiving hole (32).

7. The support roller according to claim 1, characterized in that, The receiving holes (32) are provided in a plurality of spaced apart along the circumference of the thrust surface (31).

8. The support roller according to claim 1, characterized in that, Along the axial direction, the distance between the thrust surface (31) and the side of the bearing (4) facing the thrust surface (31) is a, which satisfies 0.3mm≤a≤0.6mm.

9. The support roller according to claim 1, characterized in that, The end cap (3) is axially oriented towards the wheel body (2) and forms a floating seal chamber with the wheel body (2). A floating oil seal (6) is provided in the floating seal chamber and surrounds the outer periphery of the thrust surface (31).

10. A type of operating machinery, characterized in that, Includes the support roller according to any one of claims 1 to 9.

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