A wheel end structure for an engineering machine drive axle

Abstract

The utility model relates to engineering machinery transmission part technical field, concretely relates to an engineering machinery drive axle wheel edge structure, including wheel hub, axle housing and inner toothed ring, is equipped with bearing and oil seal between wheel hub and axle housing, is equipped with the installation position for spacing oil seal, the movable position for oil seal outer ring rotation, the barrier position for preventing silt from entering on axle housing, installation position, movable position, barrier position set from inside to outside in the form of ladder, is equipped with the sunken containing area for bearing installation on axle housing, inner toothed ring is located axle housing, wheel hub side, and inner toothed ring and axle housing are connected through support assembly between, and support assembly includes support body, bolt and the installation pad of the design of the adjustment according to safety factor and structure space, this scheme can save material, avoid silt and enter the inside influence structure's performance of wheel hub.

Description

Technical Field

[0001] This utility model relates to the field of engineering machinery transmission components, and specifically provides a wheel-side structure for an engineering machinery drive axle. Background Technology

[0002] The wheel-side structure of the drive axle is an end-drive device located near the wheel hub in the drive axle of modern heavy vehicles, off-road vehicles, and construction machinery. The core function of this structure is to further reduce the speed and increase the torque, thereby improving the vehicle's traction and passability, while reducing the load on the main reducer and half shaft. The drive axle wheel-side structure is a key design for improving the power and passability of heavy vehicles.

[0003] Traditional drive axle housing wheel-side structure, such as Figure 1 As shown, it typically consists of components such as axle housing, wheel hub, and internal gear ring. It can fix the internal gear ring and wheel hub in the assembly and output torque. The traditional structure has the following main shortcomings: 1. Due to the large alternating load on the wheel side of the drive axle of engineering machinery, in order to prevent the bolts from loosening and solve the problem of fixing the internal gear ring, four parts are often used for fastening and supporting: internal gear ring, bolts, washers, and pins. This structure has the following drawbacks: 1) The actual effective area of ​​the washer is... Figure 2 1) The shaded area (as shown at M) in the diagram easily leads to material waste; 2) Large and thin gaskets are prone to significant deformation during heat treatment, so such gaskets are generally made of thicker material, which also affects the overall structural space design; 3) This structure, which is prone to deformation during heat treatment, limits the hardness obtained after quenching. If the hardness is too low, the yield strength of the gasket will be insufficient. To ensure the reliability of bolt tightening, the boss part under the bolt head (as shown at M) must be machined off. Figure 3 As shown at point N in the diagram, increasing the contact area between the washer and the bolt will increase the cost of parts procurement compared to using standard bolts directly.

[0004] 2. The oil seal design of the drive axle housing wheel edge structure has assembly limits on the wheel hub (e.g., Figure 1 As shown in the image, it is first mounted on the wheel hub, and then mounted on the axle housing together with the wheel hub. This has the following drawbacks: 1) At this time, a bearing inner ring is already installed on the axle housing. The oil seal needs to pass through the bearing inner ring to be assembled on the axle housing. This mode is limited by the size of the bearing inner ring and the inner diameter of the oil seal, affecting the bearing selection and the overall structure design of the axle housing and hub; 2) The space between the oil seal and the axle housing is large, which makes it easy for mud and sand to accumulate.

[0005] Therefore, how to solve the above problems is an important issue in the design of the wheel-side structure of the drive axle of engineering machinery. Utility Model Content

[0006] To solve the above problems, this utility model provides a wheel-side structure for a drive axle of engineering machinery and its oil seal installation method, which can ensure structural performance and save materials and costs.

[0007] This utility model provides a wheel-side structure for an engineering machinery drive axle, including a hub, an axle housing, and an internal gear ring. A bearing and an oil seal are provided between the hub and the axle housing. The axle housing has an installation position for limiting the oil seal, a movable position for allowing the outer ring of the oil seal to rotate, and a barrier position for preventing mud and sand from entering. The installation position, movable position, and barrier position are arranged in a stepped manner from the inside to the outside. The axle housing also has a recessed receiving area for bearing installation, located inside the oil seal. After the bearing is installed, there is an anti-interference gap between the bearing and the oil seal. The internal gear ring is located on the side of the axle housing and hub. The internal gear ring and the axle housing are connected by a support assembly. The support assembly includes a support body connected to the internal gear ring and bolts connecting the support body to the axle side. An installation pad that can be adjusted according to the safety factor and structural space is provided between the axle side, the support body, and the bolts.

[0008] Furthermore, the mounting position includes a first bottom edge and a first side edge formed on the axle housing, the first bottom edge and the first side edge being perpendicular to each other and forming a limiting right angle, and the inner ring of the oil seal abutting the limiting right angle.

[0009] Furthermore, the movable part includes a second bottom edge and a second side edge disposed perpendicular to the second bottom edge. The second bottom edge is connected to the first side edge, and the second side edge is connected to the side of the second bottom edge away from the first side edge. The outer ring of the oil seal is located above the second bottom plate, and there is a movable gap between the outer ring of the oil seal and the second side edge.

[0010] Furthermore, the barrier includes a third bottom edge and a third side edge perpendicular to the third bottom edge. The third bottom edge is connected to the second side edge, and the third side edge is connected to the side of the third bottom edge away from the second side edge. The third bottom edge and the third side edge are perpendicular to each other and form a barrier right angle. The hub includes an outer end portion located at the outer end of the outer ring of the oil seal. The outermost part of the outer end portion is located above the third bottom edge. The barrier portion blocks the mud and sand flowing in between the outer end portion and the third side edge at the barrier right angle.

[0011] Furthermore, let e be the distance between the outer end and the third side, where e ranges from 0.1mm to 0.6mm.

[0012] Furthermore, let f be the distance of the movable clearance between the outer ring of the oil seal and the second side, where f ranges from 0.5mm to 2mm.

[0013] Furthermore, the axle housing has stepped connecting holes, which include a threaded area and a loose area, with the inner diameter of the loose area being larger than that of the threaded area; the bolt includes a threaded rod located inside the connecting hole and a nut located outside the connecting hole; the outer end of the support body is connected to the internal gear ring, and the mounting pad includes a washer located between the nut and the inner end of the support body, and a connecting pin located between the threaded rod and the inner ends of the axle housing and the support body, with the connecting pin located within the loose area.

[0014] Furthermore, the washer and connecting pin are separate structures; the washer is designed according to the specifications of the standard bolts. When the bolt selection range is M10~M20 and the safety factor is designed to be 1.2~3, the washer area is selected from 67~955mm². 2 .

[0015] Furthermore, the mounting pad is a hollow structure, that is, the mounting pad includes a central through hole, and the gasket and connecting pin are an integral structure; the gasket includes a first pad surface that abuts against the nut and a second pad surface that abuts against the inner end of the support body, and a third pad surface connects the first pad surface and the second pad surface. The first pad surface is parallel to the second pad surface, and the first pad surface is perpendicular to the third pad surface.

[0016] Furthermore, let the inner diameter of the intermediate through hole be d, the distance between the connecting pin and the wall of the intermediate through hole be h, the connection between pad one and the wall of the intermediate through hole be chamfer A, the connection between pad three and pad two be chamfer B, and the connection between pad two and the connecting pin be chamfer C; wherein the chamfer angles of chamfer A and chamfer B are not greater than 45°, the chamfer lengths of chamfer A and chamfer B are not greater than 0.5mm, the chamfer radius of chamfer C is not greater than 0.5mm, d is 0.4mm-0.8mm larger than the nominal diameter of the bolt, and h is 0mm-0.1mm.

[0017] Compared with the prior art, the present invention can achieve the following beneficial effects: 1. The oil seal is designed to be positioned on the axle housing. Based on the internal skeleton of the box-type oil seal, the inner ring of the oil seal is also supported by the skeleton. With the inner ring as the limit, the oil seal is installed on the axle housing first, and then the bearing inner ring is installed. This can avoid interference between the oil seal and the bearing inner ring. The right-angle structure is designed according to the oil seal installation space, which can effectively prevent mud and sand from entering the wheel hub and reduce the gap between the oil seal and the axle housing, preventing excessive mud and sand accumulation.

[0018] 2. The gasket and connecting pin are separate structures. The gasket is designed according to the specifications of the standard bolt. Small gaskets can be used. Small gaskets are simple to heat treat and can achieve quenching hardness close to the material limit. They are also thinner and can be used directly with standard bolts without the need for custom bolts, which improves versatility.

[0019] 3. The gasket and connecting pin are integrated into one structure, combining the functions of the gasket and the connecting pin. The upper part functions the same as the gasket, and can be designed as a small gasket with a hardness close to the material's limit hardness after quenching. It is also thinner and its diameter can be designed more flexibly according to the safety factor and structural space, reducing the number of parts and avoiding material waste. At the same time, it is easier to assemble than ordinary hollow connecting pins. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the traditional drive axle wheel-side structure in the background art; Figure 2 It is based on the structural diagram of the gasket in the background art; Figure 3 It is based on the structural diagram of the bolt in the background art; Figure 4 This is a schematic diagram of the drive axle wheel side structure according to Embodiment 1 of this utility model; Figure 5 yes Figure 4 A magnified view of a section at point K; Figure 6 yes Figure 4 A magnified view of a section at point K; Figure 7 yes Figure 4 A magnified view of a section at point Z; Figure 8 This is a schematic diagram of the mounting pad provided according to Embodiment 1 of this utility model; Figure 9 This is a schematic diagram of the connecting pin provided in Embodiment 2 of this utility model; Figure 10 This is a schematic diagram of the connecting pin provided according to Embodiment 2 of this utility model.

[0021] The reference numerals in the attached drawings include: hub 1, axle housing 2, internal gear ring 3, bearing 4, bearing one 5, bearing two 6, oil seal 7, inner ring of oil seal 8, outer ring of oil seal 9, mounting position 10, movable position 11, blocking position 12, receiving area 13, anti-interference gap 14, first bottom edge 15, first side edge 16, limiting right angle 17, second bottom edge 18, second side edge 19, movable gap 20, third bottom edge 21, third side edge 22, blocking right angle 23, outer end 24, support body 25, screw 26, nut 27, threaded area 28, empty sleeve area 29, gasket 30, connecting pin 31, connecting hole 32. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this utility model clearer, the following description is provided in conjunction with the appendix. Figure 1-10The present invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and do not constitute a limitation thereof. Example 1

[0023] A drive axle wheel-side structure for engineering machinery, including Figure 1 The diagram shows a hub 1, axle housing 2, and internal gear ring 3. A bearing 4 and an oil seal 7 are provided between the hub 1 and the axle housing 2. The bearing 4 includes a first bearing 5 and a second bearing 6. The oil seal 7 includes an inner oil seal ring 8 and an outer oil seal ring 9. The axle housing 2 is equipped with... Figure 5 The mounting position 10 for limiting the oil seal 7, the movable position 11 for allowing the outer ring 9 of the oil seal to rotate, and the barrier position 12 for preventing mud and sand from entering are shown. The mounting position 10, the movable position 11, and the barrier position 12 are arranged in a stepped manner from the inside to the outside. The bridge housing 2 is also provided with a recessed receiving area 13 for the bearing 4 to be installed. The receiving area 13 is located inside the oil seal 7. There is an anti-interference gap 14 between the bearing 5 in the bearing 4 and the oil seal 7. The bearing 5 is located close to the oil seal 4.

[0024] Mounting position 10 includes a first bottom edge 15 and a first side edge 16 formed on the bridge housing 2. The first bottom edge 15 and the first side edge 16 are perpendicular to each other and form a limiting right angle 17. The inner ring of the oil seal 8 abuts against the limiting right angle 17. The movable position 11 includes a second bottom edge 18 and a second side edge 19 arranged perpendicular to the second bottom edge 18. The second bottom edge 18 is connected to the first side edge 16, and the second side edge 19 is connected to the side of the second bottom edge 18 away from the first side edge 16. The outer ring of the oil seal 9 is located above the second base plate. There is a movable gap 20 between the outer ring of the oil seal 9 and the second side edge 19. When the outer ring of the oil seal 9 rotates, the movable gap 20 can provide rotation space for the outer ring of the oil seal 9.

[0025] The barrier position 12 includes a third bottom edge 21 and a third side edge 22 perpendicular to the third bottom edge 21. The third bottom edge 21 is connected to the second side edge 19, and the third side edge 22 is connected to the side of the third bottom edge 21 away from the second side edge 19. The third bottom edge 21 and the third side edge 22 are perpendicular to each other and form a barrier right angle 23. The barrier right angle 23 can effectively prevent mud and sand from entering the interior of the wheel hub 1 and can reduce the gap between the oil seal 4 and the axle housing 2. The wheel hub 1 includes an outer end 24 located at the outer end of the outer ring 9 of the oil seal. The outermost part of the outer end 24 is located above the third bottom edge 21. The barrier position 12 blocks the mud and sand flowing in between the outer end 24 and the third side edge 22 at the barrier right angle 23.

[0026] Let e ​​be the distance between the outer end 24 and the third side 22, and f be the distance between the oil seal outer ring 9 and the second side 19 in the movable clearance 20. To prevent the hub 1, the oil seal outer ring 9 from wearing against the axle housing 2 during operation, and to prevent excessive sediment deposition caused by excessive gaps, the range of e is set to 0.1mm-0.6mm, and the range of f is set to 0.5mm-2mm.

[0027] like Figure 1 As shown in the background technology, the outer ring 5 of the oil seal is used to limit the position on the hub 1. At this time, the inner ring 8 of the oil seal is close to the bearing 5, which is prone to interference with the bearing 5 during use. In this embodiment, the oil seal 7 is positioned on the axle housing 2 by the inner ring 8 of the oil seal. At this time, there is an anti-interference gap 14 between the inner ring 8 of the oil seal and the bearing 5, which provides sufficient separation space. During use, the oil seal 7 will never interfere with the bearing 5, which greatly ensures the performance.

[0028] The internal gear ring 3 is located on the side of the axle housing 2 and the hub 1. The internal gear ring 3 is connected to the axle housing 2 through a support assembly. The support assembly includes a support body 25 connected to the internal gear ring 3 and a bolt connecting the support body 25 to the axle side. There are mounting pads between the axle side, the support body 25 and the bolt that can be adjusted according to the safety factor and structural space. The axle housing 2 has a stepped connection hole 32. The connection hole 32 includes a threaded area 28 and a loose area 29. The inner diameter of the loose area 29 is larger than the inner diameter of the threaded area 28. The bolt includes a screw 26 located in the connection hole 32 and a nut 27 located outside the connection hole 32. The outer end of the support body 25 is connected to the internal gear ring 3. The outer end of the support body 25 is the end of the support body 25 away from the screw 26.

[0029] The mounting pad includes a washer 30 located between the nut 27 and the inner end of the support body 25, and a connecting pin 31 located between the screw 26 and the inner end of the bridge housing 2 and the support body 25. The connecting pin 31 is located in the empty sleeve area 29. The mounting pad is a hollow structure, that is, the mounting pad includes a through hole in the middle. The washer 30 and the connecting pin 31 are an integral structure. The hardness of the washer 30 is close to the material's limit hardness after quenching, and the thickness is smaller than that of the washer 30 in the prior art. The diameter can be designed more flexibly according to the safety factor and structural space, reducing the number of parts and avoiding material waste. At the same time, it is easier to assemble than the ordinary hollow connecting pin 31.

[0030] The washer 30 includes a washer surface one that abuts against the nut 27 and a washer surface two that abuts against the inner end of the support body 25. A washer surface three connects the washer surface one and the washer surface two. The washer surface one is parallel to the washer surface two and perpendicular to the washer surface three. Let the inner diameter of the intermediate through hole be d, the distance between the connecting pin 31 and the wall of the intermediate through hole be h, the connection between the washer surface one and the wall of the intermediate through hole be chamfer A, the connection between the washer surface three and the washer surface two be chamfer B, and the connection between the washer surface two and the connecting pin 31 be chamfer C. The chamfer angles of chamfers A and B are no greater than 45°, the chamfer lengths of chamfers A and B are no greater than 0.5mm, the chamfer radius of chamfer C is no greater than 0.5mm, d is 0.4mm-0.8mm larger than the nominal diameter of the bolt, chamfers A and B are sharp corners, and chamfer C is a rounded corner. The positions of chamfers A, B, and C are as follows: Figure 8 As shown, the above design can ensure the effective contact area between the connecting pin 31 and the bolt surface and the supporting surface of the internal gear ring 3. At the same time, h is 0mm-0.1mm, which can ensure the key positioning function of the connecting pin 31.

[0031] The new pin sleeve consists of two parts, upper and lower. The upper part functions like a gasket and can be designed like the small gasket mentioned above. Its hardness is close to the material's limit hardness after quenching, and its thickness is smaller. The diameter can be designed more flexibly according to the safety factor and structural space, reducing the number of parts and avoiding material waste. At the same time, it is easier to assemble than ordinary hollow locating pins.

[0032] In this embodiment, the installation steps of the oil seal 7 are as follows: First, assemble the outer rings of bearing 5 and bearing 6 onto the hub 1; then install the oil seal 7 onto the axle housing, specifically at mounting position 10 on the axle housing, and abut the oil seal 7 against the limiting right angle 17; then install the inner ring of bearing 5 onto the axle housing; then assemble the hub 1 with the outer rings of bearing 5 and bearing 6 installed onto the axle housing; finally, install the inner ring of bearing 6 onto the axle housing.

[0033] The installation method in the background technology is as follows: first, the bearing 4 is installed on the axle housing 2, then the oil seal 7 is installed on the wheel hub 1, and then the wheel hub 1 and the oil seal 7 are installed together. This method has poor versatility, and when the inner ring of the bearing 5 is larger than the inner diameter of the oil seal 7, there is a problem with installation. The installation method in this embodiment is not limited by the inner diameter of the bearing 5, nor by the inner diameter of the oil seal 7, and does not affect the selection of the bearing 4 or the overall structural design of the axle housing 2 and the wheel hub 1, thus having greater versatility. Example 2

[0034] The difference between this embodiment and Embodiment 1 is that the washer 30 and the connecting pin 31 are separate structures. The washer 30 is designed according to the specifications of the standard bolt. When the bolt selection range is M10~M20 and the safety factor is designed to be 1.2~3, the area of ​​the washer 30 is selected from 67~955mm². 2 .like Figure 9 , Figure 10 As shown, machining the connecting pin 31 into a single-sided toothed or double-sided toothed structure can further increase the overall reliability of the structure.

[0035] Compared to the larger and thinner shim 30 in the comparative document, the shim 30 in this embodiment is smaller and selected according to the parameter requirements. The smaller shim is simple to heat treat and can achieve a hardness close to the material limit. It is also thinner and can directly use standard bolts without the need for custom bolts. The specific size of the shim 30 can be flexibly designed according to the required safety factor, without causing material waste.

[0036] Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0037] The specific embodiments of this utility model described above do not constitute a limitation on the scope of protection of this utility model. Any other corresponding changes and modifications made based on the technical concept of this utility model should be included within the scope of protection of the claims of this utility model.

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