High performance waterproof rear axle

Abstract

The application relates to the technical field of automobile rear axles, in particular to a high-performance waterproof rear axle which comprises a liquid-expanding axle housing and a rear axle body; the rear axle body is arranged in the liquid-expanding axle housing; the liquid-expanding axle housing comprises an axle housing main body, a baffle and a reinforcing ring; the baffle and the reinforcing ring are fixedly connected with the axle housing main body in a welding mode; the axle housing main body is an integrated structure and is formed through a hydraulic bulging process; the axle housing main body comprises a high-stress area and a low-stress area; the wall thickness of the high-stress area is greater than that of the low-stress area; the high-stress area comprises an end portion shaft head welding area and a plate spring corresponding connecting area; the low-stress area comprises a middle portion circular shell area; the wall thickness of the middle portion circular shell area increases gently from the center to the two sides. The waterproof rear axle has the beneficial effects of waterproof, oil-proof and dust-proof functions, light weight and saved manufacturing materials.

Description

Technical Field

[0001] This application relates to the field of automotive rear axle technology, and in particular to a high-performance waterproof rear axle. Background Technology

[0002] With the rapid development of the automotive industry, global demand for automobiles continues to grow, and vehicles are being used in increasingly diverse scenarios, from daily commutes in cities to freight transport in complex road conditions. Against this backdrop, the performance requirements for core vehicle components are constantly increasing, with the performance of the rear axle being particularly critical.

[0003] Currently, a significant number of vehicles on the market exhibit serious problems with the waterproofing performance of their rear axles when facing complex road conditions, especially flooded sections. When the rear axle is submerged, critical components such as gears and bearings are highly susceptible to corrosion. Water contact with metal parts triggers a rapid electrochemical reaction, causing a rust layer to form on the surface. This rust layer not only damages the original precision and surface finish of the components but also reduces their mechanical properties. For example, corrosion roughens the gear teeth, generating additional vibration and noise during operation and reducing transmission efficiency; bearing corrosion affects its rotational flexibility, increases frictional resistance, and in severe cases, can even cause the bearing to seize, affecting the vehicle's normal operation.

[0004] Meanwhile, with increasingly stringent environmental regulations and consumers' pursuit of fuel economy and handling, lightweighting has become a crucial trend in the automotive industry. As a vital component of the vehicle, achieving lightweighting of the rear axle is equally urgent. However, existing rear axle design and manufacturing technologies often struggle to maintain waterproofing in the pursuit of weight reduction. While the application of some lightweight materials reduces the weight of the rear axle, limitations in the material's inherent properties or manufacturing processes significantly compromise its waterproofing and corrosion resistance.

[0005] Furthermore, most existing rear axle waterproofing measures have limitations. Traditional sealing methods, such as rubber sealing rings, are prone to aging and deformation after long-term use, leading to a decline in sealing performance and an inability to effectively prevent moisture intrusion. Moreover, these sealing measures are even less effective in extreme situations such as high-pressure water impact or prolonged immersion.

[0006] In summary, existing rear axle technologies have significant problems and shortcomings in terms of waterproofing and lightweighting. There is an urgent need for a high-performance waterproof axle technology that can effectively solve the problem of rust after the rear axle is submerged in water, while also meeting the development needs of lightweight vehicles, thereby improving the overall performance and reliability of the vehicle. Utility Model Content

[0007] The purpose of this application is to provide a high-performance waterproof rear axle to solve at least one of the technical problems existing in the prior art.

[0008] To solve the above-mentioned technical problems, this application provides a high-performance waterproof rear axle, including a hydraulically expanded axle housing and a rear axle body; The rear axle body is disposed within the hydraulic expansion bridge housing; The hydraulic expansion bridge housing includes a bridge housing body, baffles, and reinforcing rings; The baffle and the reinforcing ring are fixedly connected to the bridge housing body by welding. The bridge housing body is an integral structure, formed by a hydraulic bulging process; The bridge shell body includes a high-stress area and a low-stress area; The wall thickness of the high-stress zone is greater than the wall thickness of the low-stress zone; The high-stress area includes the end shaft welding area and the corresponding connection area of ​​the leaf spring; The low-stress zone includes the central circular shell region; The wall thickness gradually increases from the center of the central circular shell region to both sides.

[0009] The existing axle housing welding process involves assembling and welding the upper axle housing plate, large and small triangular plates, rear cover, reinforcing ring, and half-shaft sleeve. The existing full-welding process involves full welding of the straight seam and three-way joint of the axle housing, circumferential welding of the rear cover, circumferential welding of the reinforcing ring, and circumferential welding of the half-shaft sleeve. In contrast, the axle housing body of this application is integrally formed, requiring only the welding of the baffle plate and reinforcing ring after forming. The existing rear cover and other components have limited sealing performance due to the presence of weld seams during welding. This application, compared to the existing technology, uses liquid expansion for one-time forming, eliminating weld seams and solving problems such as insufficient penetration in longitudinal welds and high stress in the rear cover welds leading to oil leakage, while also resulting in a better product appearance.

[0010] Furthermore, this application employs a hydraulic bulging process, which allows for controllable wall thickness at various points on the axle housing body. This increases the wall thickness at the end axle welding area and the leaf spring location, thereby enhancing the strength of this area and improving overall performance. Simultaneously, the wall thickness of the central circular shell area is appropriately reduced. This area has a large cross-section and low stress, and reducing the wall thickness can reduce the overall weight and material usage. According to comparative test data, the hydraulic bulging axle housing of this application is 5%-10% lighter than the existing stamped and welded axle housing, with a material utilization rate as high as 90%, saving approximately 25% of material compared to stamping and welding.

[0011] Furthermore, the rear axle body includes a half-shaft and a half-shaft sleeve; A half-shaft oil seal unit is provided between the half-shaft and the half-shaft sleeve to prevent gear oil in the device from seeping out from the gap between the half-shaft and the half-shaft sleeve; The end face of the half shaft is coated with sealant to prevent external water and impurities from entering the joint area between the half shaft and other components.

[0012] Furthermore, the rear axle body also includes a wheel hub unit; The hub unit includes a bearing unit and a hub; The hub is rotatably connected to the bearing unit; The hub has a petal structure, which is used for flange connection with other structures. The petals of the petal structure have gaps between them to reduce material usage and reduce overall weight.

[0013] Furthermore, the bearing unit includes an outer bearing and an inner bearing; Both the outer and inner bearings are tapered roller bearings and are arranged symmetrically.

[0014] Furthermore, an external oil seal unit is provided at the outer end of the outer bearing; An inner oil seal unit is provided at the inner end of the inner bearing.

[0015] Furthermore, the outer oil seal unit is a double-lip oil seal, including a first oil guide lip and a first main lip; The first oil guide lip is used to guide lubricating oil into the oil seal and at the same time scrape off excess oil; The first main lip is used to seal the external space of the outer bearing.

[0016] Preferably, the outer oil seal unit is made of fluororubber.

[0017] Furthermore, the inner oil seal unit is a multi-lip oil seal, including a second main lip, an auxiliary lip, and a second oil guide lip; The second main lip is used to prevent oil and water leakage; The second oil guide lip is used to guide the flow of liquid and prevent external impurities from entering the device. The auxiliary lip is used to prevent external impurities such as water and mud from entering the device.

[0018] Furthermore, an O-ring is provided between the inner end face of the hub and the end face of the half-shaft sleeve to prevent water and oil from seeping into the hub.

[0019] Furthermore, the rear axle body includes a main reducer, which is equipped with a main reducer oil seal and a dust cover to prevent water, oil or particulate matter from entering the main reducer.

[0020] Furthermore, the main oil seal includes a rubber part, a skeleton, a spring, and lubricating grease; The frame is L-shaped, consisting of a horizontal section and a vertical section; The vertical part abuts against the outer inner wall of the main reducer; The rubber portion is disposed on the skeleton; The area where the rubber part overlaps the horizontal part of the frame is provided with a secondary lip; The end of the secondary lip that is away from the skeleton abuts against the lower end of the dust cover; The end of the rubber part away from the vertical part is abutted against the inner wall of the main reducer by a spring, and is provided with a main lip. The main reducer is provided with a flange, and the upper end of the dust cover abuts against the flange, so that the dust cover is positioned between the flange and the secondary lip, and the secondary lip tends to force the dust cover against the flange.

[0021] Preferably, there is at least one main lip and one secondary lip. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the specific embodiments of this application or 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 this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This is a three-dimensional structural schematic diagram of the hydraulic expansion bridge shell disclosed in this application; Figure 2 This is a schematic diagram showing the change in cross-sectional thickness at the center of the hydraulic expansion bridge shell disclosed in this application; Figure 3 This is a three-dimensional structural diagram of the hydraulic expansion bridge housing with mounting baffles disclosed in this application; Figure 4 This is a three-dimensional structural diagram of the hydraulic expansion bridge shell with reinforcing ring disclosed in this application; Figure 5 This is a partial sectional view of the rear axle body from the main viewpoint disclosed in this application; Figure 6 for Figure 5 A magnified view of the section section; Figure 7 A structural diagram showing the area where the sealant will be applied; Figure 8 This is a partial cross-sectional view of the hub unit disclosed in this application; Figure 9 This is a front view of the hub unit disclosed in this application; Figure 10 This is a side sectional view of the hub unit disclosed in this application; Figure 11This is a schematic diagram of the planar structure of the external oil seal unit; Figure 12 This is a schematic diagram of the planar structure of the internal oil seal unit; Figure 13 A partial sectional view of the main reducer; Figure 14 This is a schematic diagram of the planar structure of the main oil seal disclosed in this application.

[0024] Figure label: 1-Hydraulic expansion axle housing; 2-Rear axle body; 3-Axle housing main body; 4-Baffle; 5-Reinforcing ring; 6-High stress area; 7-Low stress area; 8-Half shaft; 9-Half shaft sleeve; 10-Half shaft oil seal unit; 11-Sealant; 12-Hub unit; 13-Bearing unit; 14-Hub; 15-Outer bearing; 16-Inner bearing; 17-Outer oil seal unit; 18-Inner oil seal unit; 19-First oil guide lip; 20-First main lip; 21-Second main lip; 22-Auxiliary lip; 23-Second oil guide lip; 24-O-ring; 25-Main reducer; 26-Main reducer oil seal; 27-Dust cover; 28-Rubber part; 29-Skeleton; 30-Spring; 31-Grease; 32-Horizontal part; 33-Vertical part; 34-Secondary lip; 35-Main lip; 36-Flange. Detailed Implementation

[0025] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0026] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0027] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0028] It should also be noted that the specific embodiments or implementation methods described below are a series of optimized settings listed in this application to further explain the specific application content, and these settings can be combined or used in conjunction with each other.

[0029] The present application will be further explained below with reference to specific implementation methods.

[0030] like Figures 1-2 As shown, this embodiment provides a high-performance waterproof rear axle, including a hydraulically expanded axle housing 1 and a rear axle body 2; The rear axle body 2 is disposed inside the hydraulic expansion bridge housing 1; The hydraulic expansion bridge housing 1 includes a bridge housing body 3, a baffle 4, and a reinforcing ring 5; The baffle 4 and the reinforcing ring 5 are fixedly connected to the bridge shell body 3 by welding. The bridge shell body 3 is an integrated structure, formed by hydraulic bulging process; The bridge shell body 3 includes a high-stress area 6 and a low-stress area 7; The wall thickness of the high-stress region 6 is greater than the wall thickness of the low-stress region 7; The high-stress zone 6 includes the end shaft welding area and the corresponding connection area of ​​the leaf spring; The low-stress zone 7 includes a central circular shell region; The wall thickness gradually increases from the center of the central circular shell region to both sides.

[0031] The existing axle housing body welding process involves assembling and welding the upper axle housing plate, large and small triangular plates, rear cover, reinforcing ring 5, and half-shaft sleeve 9, etc. The existing full-welding process for the axle housing involves full welding of the straight seam and three-way joint of the axle housing, circumferential welding of the rear cover, circumferential welding of the reinforcing ring, and circumferential welding of the half-shaft sleeve 9. In contrast to the existing technology, the axle housing body 3 of this application is integrally formed, requiring only the welding of the baffle plate 4 and reinforcing ring 5 after forming. In contrast, the existing technology's rear cover and other components have limited sealing performance due to the presence of weld seams during welding. This application, compared to the existing technology, uses liquid expansion for one-time forming, eliminating weld seams and solving problems such as insufficient penetration in longitudinal weld seams and high stress in the rear cover weld seams leading to oil leakage, while also resulting in a better product appearance quality.

[0032] Furthermore, this application employs a hydraulic bulging process, which allows for controllable wall thickness at various points on the axle housing body 3. This increases the wall thickness at the end axle welding area and the leaf spring location, thereby improving the strength of this area and enhancing overall performance. Simultaneously, the wall thickness of the central circular shell area is appropriately reduced. This area has a large cross-section and low stress, and reducing the wall thickness can reduce the overall weight and material usage. According to comparative test data, the hydraulic bulging axle housing of this application is 5%-10% lighter than the existing stamped and welded axle housing, with a material utilization rate as high as 90%, saving approximately 25% of material compared to stamping and welding.

[0033] For the purpose of overall lightweight design of the time structure, this application uses Q345 material for the hydraulic expansion bridge shell 1, and the forming method is hydraulic expansion molding. The inner cavity and wall thickness of the bridge shell are finally determined through finite element software and a large amount of experimental data. The formed product has a variable cross section and variable wall thickness, which is close to the strength beam. The wall thickness of the end shaft welding area and the leaf spring position is increased to reduce the stress in the area and improve the overall performance. The wall thickness in the middle is appropriately reduced. The cross section of this area is large and the stress is low. Reducing the wall thickness can reduce the weight. According to the test data, it is 5%-10% lighter than the stamped and welded bridge shell, and the material utilization rate is as high as 90%, saving about 25% of the material compared with stamping and welding.

[0034] Existing technologies require multiple welding steps for the axle housing, such as assembling and welding the upper axle housing plate, large and small triangular plates, rear housing cover, reinforcing ring 5, and half-shaft sleeve 9. In contrast, this application only requires welding the baffle 4 and reinforcing ring 5 (e.g., Figures 3-4 As shown in the figure, the welding process is reduced, which can effectively improve the production quality. Furthermore, the integrated seamless design of the hydraulic expansion bridge housing 1 and the rear cover solves the problems of insufficient penetration of the longitudinal weld and high stress in the rear cover weld, which can easily lead to oil leakage.

[0035] As a further embodiment of this example, the rear axle body 2 includes a half-shaft 8 and a half-shaft sleeve 9; A half-shaft oil seal unit 10 is provided between the half-shaft 8 and the half-shaft sleeve 9 to prevent gear oil in the device from seeping out from the gap between the half-shaft 8 and the half-shaft sleeve 9; The end face of the half shaft 8 is coated with sealant 11 to prevent external water and impurities from entering the joint area between the half shaft 8 and other components.

[0036] To prevent gear oil leakage, an oil seal for the half-shaft 8 is added at the junction of the half-shaft sleeve 9 and the half-shaft 8, providing a good seal. The half-shaft oil seal unit 10 can employ existing oil seal technology, which can prevent gear oil from leaking out from the gap between the half-shaft 8 and the half-shaft sleeve 9, thereby reducing the risk of gear oil leakage at the mating surface between the half-shaft 8 and the wheel hub 14. Oil leakage often occurs at this point in commonly used axles in the current field; therefore, this application includes an oil seal for the half-shaft 8.

[0037] Applying 5900 silicone sealant 11 to the end faces of the outer half-shaft 8 and hub 14 forms an effective barrier, preventing external water and impurities from intruding into the joint between the half-shaft 8 and hub 14. The intrusion of water and impurities can lead to rust and accelerated wear of parts, affecting the normal operation of the entire transmission system. Sealant 11 adheres tightly to the surfaces of the two components, preventing the intrusion of adverse external factors. On the other hand, sealant 11 also helps prevent internal leakage. Even if a small amount of gear oil attempts to seep from the joint surface, sealant 11 can effectively block it, increasing the overall system's airtightness. This ensures that the gear oil flows within a specified area, maintaining good lubrication and improving transmission efficiency and system reliability.

[0038] As a further embodiment of this embodiment, the rear axle body 2 also includes a hub unit 12; The hub unit 12 includes a bearing unit 13 and a hub 14; The hub 14 is rotatably connected to the bearing unit 13; The hub 14 has a petal structure, which is used for flange connection with other structures. The petals of the petal structure have gaps between them to reduce material usage and reduce overall weight.

[0039] As a further embodiment of this embodiment, the bearing unit 13 includes an outer bearing 15 and an inner bearing 16; Both the outer bearing 15 and the inner bearing 16 are tapered roller bearings and are arranged symmetrically.

[0040] As a further embodiment of this embodiment, an outer oil seal unit 17 is provided at the outer end of the outer bearing 15; An inner oil seal unit 18 is provided at the inner end of the inner bearing 16.

[0041] The hub unit 12 features a compact design, effectively reducing the dimensions of its boundary dimensions and related components. Its integrated design reduces the weight of the hub 14, axle head, and half-axle sleeve 9. Specifically, the manufacturing process of the hub 14 is changed from casting to forging. Secondly, the assembly weight is reduced by using a petal-shaped flange, and the bearing outer skin is eliminated, directly machining the inner cavity of the hub 14 to the existing outer skin dimensions. This increases the inner wall space, thereby increasing the roller size, improving load-bearing capacity, and better handling more overload conditions. The bearing dimensions are determined through theoretical calculations. Finally, by controlling the bearing clearance, selecting the grease, and adjusting the grease quantity, a maintenance-free unit is achieved. These measures not only improve the performance of the hub 14 assembly but also provide users with a more convenient and reliable user experience.

[0042] As a further embodiment of this embodiment, the outer oil seal unit 17 is a double-lip oil seal, including a first oil guide lip 19 and a first main lip 20; The first oil guide lip 19 is used to guide lubricating oil into the oil seal and scrape off excess oil. The first main lip 20 is used to seal the external space of the outer bearing 15.

[0043] In a preferred embodiment of this invention, the external oil seal unit 17 is made of fluororubber.

[0044] Fluororubber is chosen as the oil seal material due to its excellent high-temperature resistance, resistance to strong corrosive media, and resistance to strong oxidizers. Considering the complexities of domestic vehicle conditions, a reinforced double-lip seal is used on the outer side, significantly improving the sealing effect at the flange's outer end.

[0045] As a further embodiment of this embodiment, the inner oil seal unit 18 is a multi-lip oil seal, including a second main lip 21, an auxiliary lip 22, and a second oil guide lip 23; The second main lip 21 is used to prevent oil and water leakage; The second oil guide lip 23 is used to guide the flow of liquid and prevent external impurities from entering the device; The auxiliary lip 22 is used to prevent external impurities such as water and mud from entering the device.

[0046] To prevent water, mud, and other impurities from entering the wheel end from the outside, the inner oil seal unit 18 adopts a multi-lip design. This multi-lip design offers the following advantages: multiple lips form multiple protective barriers. When external water or mud attempts to enter, the first lip acts as a barrier. Even if a small amount of impurities breaches the first line of defense, subsequent lips can continue to block them, significantly reducing the risk of water and mud entering. Furthermore, the lips can operate as needed, automatically adjusting their sealing degree under different pressure and temperature conditions to ensure good sealing performance in various environments. This design improves the overall protection capability of the wheel end system and extends the service life of components.

[0047] As a further embodiment of this invention, an O-ring 24 is provided between the inner end face of the hub 14 and the end face of the half-shaft sleeve 9 to prevent water and oil from seeping into the hub 14.

[0048] The inner end face of the wheel hub 14 is designed with an O-ring 24, which has good elasticity and sealing performance. When installed on the inner end face of the wheel hub 14, it is tightly pressed against the end face of the half-shaft sleeve 9, forming a reliable sealing barrier. For water, the O-ring 24 prevents it from seeping into the wheel hub 14 through gaps, avoiding problems such as rust and corrosion of internal parts due to water ingress. For oil, whether gear oil or other lubricating oil, the sealing effect of the O-ring 24 prevents it from leaking into the wheel hub 14, ensuring the cleanliness of the interior of the wheel hub 14 and a normal working environment. This simple and efficient design provides an important guarantee for the normal operation of the wheel hub 14.

[0049] As a further embodiment of this embodiment, the rear axle body 2 includes a main reducer 25, and the main reducer 25 is provided with a main reducer oil seal 26 and a dust cover 27 to prevent water, oil or particulate matter from entering the main reducer 25.

[0050] As a further embodiment of this example, the main oil seal 26 includes a rubber part 28 (preferably made of fluororubber), a skeleton 29 (preferably made of SPCC material), a spring 30 (preferably made of 65Mn material) and a lubricating grease 31 (preferably made of lithium-based grease). The frame 29 is L-shaped, consisting of a horizontal part 32 and a vertical part 33. The vertical part 33 abuts against the outer inner wall of the main reducer 25; The rubber part 28 is disposed on the frame 29; The area where the rubber part 28 overlaps the horizontal part 32 of the frame 29 is provided with a secondary lip 34; The end of the secondary lip 34 away from the frame 29 abuts against the lower end of the dust cover 27; The end of the rubber part 28 away from the vertical part 33 is abutted against the inner wall of the main reducer 25 by a spring 30, and is provided with a main lip 35. The main reducer 25 is provided with a flange 36, and the upper end of the dust cover 27 abuts against the flange 36, so that the dust cover 27 is positioned between the flange 36 and the secondary lip 34, and the secondary lip 34 tends to force the dust cover 27 to abut against the flange 36.

[0051] In a preferred embodiment of this invention, at least one main lip opening 35 and one secondary lip opening 34 are provided.

[0052] The rear axle of this application needs to consider complex usage scenarios in actual use, requiring more effective waterproofing and mud-proofing measures to reduce the risk of failure under harsh road conditions and during rainy seasons. Although existing oil seals have some waterproofing properties, they may not completely prevent water and mud from entering under prolonged immersion, poor road conditions, and wading depths of up to 50 cm. Especially during vehicle movement, the impact of water flow and the entrainment of mud and sand increase the likelihood of oil seal failure. Once mud and sand enter the bearing, they disrupt the bearing's normal operating environment. The presence of mud and sand accelerates bearing wear, leading to increased friction, higher temperatures, and ultimately bearing burn-out. Bearing problems will affect the operation of the related main reducer 25, interfering with the operation of the primary and driven gears, and in severe cases, potentially causing gear breakage, affecting vehicle transmission performance and driving safety.

[0053] First, modifying the bearing housing dimensions allows for better adaptation to the new oil seal and dust cover 27, improving the overall sealing performance and stability of the structure. Optimizing the dust cover 27 design enhances its ability to block external impurities, reducing the chance of dust, sand, and other contaminants entering the main reducer 25. Second, the high-temperature resistance of the fluororubber part 28 ensures that the oil seal maintains good performance under various harsh working environments, preventing deformation or failure due to high temperatures. Its excellent resistance to strong corrosive media and strong oxidizers effectively resists chemical corrosion in harsh external environments, extending the oil seal's service life. Furthermore, the multi-lip oil seal provides multiple layers of protection, further hindering the entry of external impurities. The multiple lips working together increase sealing reliability, effectively protecting the internal components of the main reducer 25 from external impurities even under complex road conditions and harsh weather conditions.

[0054] By adopting the above technical solution, this application has the following beneficial effects: (1) This application optimizes the structure of the main reducer 25, enabling it to adapt to and safely pass through waterlogged roads. Furthermore, changing the bearing housing dimensions allows for better adaptation to the new oil seal and dust cover 27, improving the overall sealing and stability of the structure. The optimized dust cover 27 enhances the blocking effect against external impurities, reducing the likelihood of dust, mud, and sand entering the main reducer 25. The multi-lip oil seal provides multiple layers of protection, further preventing the intrusion of external impurities. The multiple lips work together to increase the reliability of the seal, effectively protecting the internal parts of the main reducer 25 from external impurities even under complex road conditions and harsh weather conditions.

[0055] 2. The wheel hub 14 adopts a maintenance-free wheel hub unit 12 structure. Its compact design reduces weight by 10kg compared to traditional rear axles, resulting in a 0.8% reduction in vehicle fuel consumption. The manufacturing process of the wheel hub 14 has been changed from casting to forging. Furthermore, the assembly weight is reduced by using a petal-shaped flange design, and the bearing outer skin is eliminated, directly machining the inner cavity of the wheel hub 14 to the original outer skin size. This allows for an increase in roller size, increasing load-bearing capacity by 20%-30% compared to cast wheel hubs. The multi-lip design of the oil seal effectively improves the rear axle's waterproof performance. This wheel hub unit 12 has passed durability tests, leakage tests (high-speed straight driving), and mud durability tests.

[0056] 3. The formed bridge shell has a variable cross-section and variable wall thickness, approaching the strength of a beam. The increased wall thickness at the end axle welding area and leaf spring location reduces stress in this area and improves overall performance. The wall thickness in the middle is appropriately reduced. This area has a large cross-section and low stress, and reducing the wall thickness can reduce weight. According to test data, it is 5%-10% lighter than stamped and welded bridge shells, with a material utilization rate of up to 90%, saving about 25% of materials compared to stamping and welding.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A high-performance waterproof rear axle, characterized in that, Includes the hydraulically expanded bridge housing and the rear axle body; The rear axle body is disposed within the hydraulic expansion bridge housing; The hydraulic expansion bridge housing includes a bridge housing body, baffles, and reinforcing rings; The baffle and the reinforcing ring are fixedly connected to the bridge housing body by welding. The bridge housing body is an integral structure, formed by a hydraulic bulging process; The bridge shell body includes a high-stress area and a low-stress area; The wall thickness of the high-stress zone is greater than the wall thickness of the low-stress zone; The high-stress area includes the end shaft welding area and the corresponding connection area of ​​the leaf spring; The low-stress zone includes the central circular shell region; The wall thickness of the central circular shell region increases gradually from the center to both sides. The rear axle body includes a half-shaft and a half-shaft sleeve; A half-shaft oil seal unit is provided between the half-shaft and the half-shaft sleeve to prevent gear oil in the device from seeping out from the gap between the half-shaft and the half-shaft sleeve; The end face of the half shaft is coated with sealant to prevent external water and impurities from entering the joint area between the half shaft and other components. The rear axle body also includes a hub unit; The hub unit includes a bearing unit and a hub; The hub is rotatably connected to the bearing unit; The hub has a petal structure, which is used for flange connection with other structures. The petals of the petal structure have gaps between them to reduce material usage and reduce overall weight.

2. The high-performance waterproof rear axle according to claim 1, characterized in that, The bearing unit includes an outer bearing and an inner bearing; Both the outer and inner bearings are tapered roller bearings and are arranged symmetrically.

3. The high-performance waterproof rear axle according to claim 2, characterized in that, An external oil seal unit is provided at the outer end of the outer bearing; An inner oil seal unit is provided at the inner end of the inner bearing.

4. The high-performance waterproof rear axle according to claim 3, characterized in that, The external oil seal unit is a double-lip oil seal, including a first oil guide lip and a first main lip; The first oil guide lip is used to guide lubricating oil into the oil seal and at the same time scrape off excess oil; The first main lip is used to seal the external space of the outer bearing.

5. The high-performance waterproof rear axle according to claim 3, characterized in that, The inner oil seal unit is a multi-lip oil seal, including a second main lip, an auxiliary lip, and a second oil guide lip; The second main lip is used to prevent oil and water leakage; The second oil guide lip is used to guide the flow of liquid and prevent external impurities from entering the device. The auxiliary lip is used to prevent external water and mud from entering the device.

6. The high-performance waterproof rear axle according to claim 1, characterized in that, An O-ring is provided between the inner end face of the wheel hub and the end face of the half-shaft sleeve to prevent water and oil from seeping into the wheel hub.

7. The high-performance waterproof rear axle according to claim 1, characterized in that, The rear axle body includes a main reducer, which is equipped with a main reducer oil seal and a dust cover to prevent water, oil or particulate matter from entering the main reducer.

8. The high-performance waterproof rear axle according to claim 7, characterized in that, The main oil seal includes a rubber part, a skeleton, a spring, and lubricating grease; The frame is L-shaped, consisting of a horizontal section and a vertical section; The vertical part abuts against the outer inner wall of the main reducer; The rubber portion is disposed on the skeleton; The area where the rubber part overlaps the horizontal part of the frame is provided with a secondary lip; The end of the secondary lip that is away from the skeleton abuts against the lower end of the dust cover; The end of the rubber part away from the vertical part is abutted against the inner wall of the main reducer by a spring, and is provided with a main lip.

9. The high-performance waterproof rear axle according to claim 8, characterized in that, The main reducer is provided with a flange, and the upper end of the dust cover abuts against the flange, so that the dust cover is positioned between the flange and the secondary lip, and the secondary lip tends to force the dust cover against the flange.

10. The high-performance waterproof rear axle according to claim 9, characterized in that, The grease is lithium-based and is used to provide oil seal lubrication for the rubber parts.

Images