Integrated high-mobility drive front axle and wheel-side system for polar low-temperature environment

Abstract

The present application relates to the field of vehicle transmission and chassis assembly technology, and particularly relates to an integrated high-passability driving front axle and wheel edge system for polar low-temperature environment, comprising a tailor-welded axle housing, a main reducer assembly, an electronic lock type differential, left and right half shafts, a wheel edge assembly and a hydraulic brake assembly; the axle housing has a regular hexagonal main body and a portal high-passability profile; the wheel edge assembly adopts a planetary gear reduction structure; key load-bearing components, gears, bearings and sealing elements respectively adopt low-temperature applicable materials and low-temperature matching parameters, and are provided with oil seals with dust-proof secondary lips; the locking or unlocking state of the electronic lock type differential can also be judged according to the ambient temperature, the speed difference between the left and right wheels and the vehicle speed; the present application can improve low-temperature brittle fracture, sealing leakage and cold start resistance, reduce the non-sprung mass, and improve the passability and braking reliability on icy and snowy roads.

Description

Technical Field

[0001] This invention relates to the field of vehicle transmission and chassis assembly technology, and in particular to an integrated high-passability drive front axle and wheel-side system for use in polar low-temperature environments. Background Technology

[0002] Polar research vehicles, ice and snow transport vehicles, and engineering vehicles operating in high-altitude and cold regions are constantly exposed to environments with low temperatures, ice and snow, mud and water, and impact loads. The drive front axle and wheel-side system not only bear the functions of power transmission, steering, and braking, but are also chassis components that are highly susceptible to road impacts and seal contamination. Their low-temperature reliability directly affects the vehicle's starting, driving, and ability to get out of trouble.

[0003] Existing front drive axles typically use a round or square axle housing made of integral casting or welded steel plates. The main reducer uses single-stage or double-stage bevel gear transmission, and the differential uses an open structure or a mechanical locking structure that is manually locked after parking. The wheel rims use cast iron or cast steel hubs, conventional planetary gear reduction mechanisms, and single-frame oil seals. The braking system mostly uses pneumatic drum brakes or pneumatic disc brakes. The materials, bearing preload, gear clearance, and sealing methods of the above structure are usually set according to normal operating conditions.

[0004] Under extreme low-temperature conditions, the impact toughness or elasticity of ordinary carbon steel, gray cast iron, and conventional rubber parts decreases, load-bearing components are at risk of brittle cracking, oil seal lips are prone to hardening and lubricating oil leakage; gears and bearings that have not been cryogenically matched may experience reduced clearance, increased frictional torque, and meshing impact due to thermal shrinkage and changes in microstructure; traditional axle housings and wheel hubs are heavy, increasing the vehicle's sinking on soft snow; open differentials cannot effectively transfer torque to wheels with traction, and mechanical locking mechanisms may jam at low temperatures; moisture in air-pressure braking systems may also freeze and cause delayed braking response. Therefore, a coordinated design is needed for the axle housing structure, main reducer and differential, wheel-side reduction and sealing, materials and fitting parameters, and braking methods. Summary of the Invention

[0005] To address these issues, the present invention provides an integrated high-passability drive front axle and wheel-side system for polar low-temperature environments, which overcomes the problems in the prior art that, while reducing assembly weight and increasing ground clearance, also improve the low-temperature brittle fracture of key load-bearing components, low-temperature failure of seals, high cold-start resistance of transmission pairs, slow differential traction response, and insufficient low-temperature reliability of braking systems.

[0006] To achieve the above objectives, this invention provides an integrated high-passability drive front axle and wheel-side system for polar cryogenic environments, comprising an axle housing, a main reducer assembly, an electronic locking differential, a left half-shaft, a right half-shaft, two wheel-side assemblies disposed at both ends of the axle housing, and hydraulic braking components corresponding to the two wheel-side assemblies respectively. The axle housing includes a regular hexagonal body, a left half-shaft sleeve, a right half-shaft sleeve, a brake caliper mounting plate, and a support plate, all parts of which are welded together to form an integral load-bearing structure. The main reducer assembly is disposed within the regular hexagonal body, and the electronic locking differential is disposed within the main reducer assembly, and is drivenly connected to the wheel-side assemblies on both sides via the left and right half-shafts respectively.

[0007] Each wheel assembly includes a steering knuckle, wheel hub, wheel-side reduction unit, front cover, and output shaft. The wheel-side reduction unit employs a planetary gear structure consisting of a sun gear, planetary gears, and a planetary gear set. The power input from the half-shaft is reduced and amplified by the wheel-side reduction unit before being transmitted to the wheel hub via the output shaft. The hydraulic braking assembly includes a hydraulic brake caliper and a brake disc. The hydraulic brake caliper is mounted on the brake caliper mounting plate on the axle housing, and the brake disc rotates synchronously with the wheel hub.

[0008] When the vehicle is under normal load, the lowest point of the axle housing is 0.4 to 0.6 times the wheel radius above the ground relative to the wheel bearing surface, thus forming a portal-type high passability profile. The total length of the axle housing can be 423.2 mm.

[0009] The main reducer housing has a cavity in the middle to accommodate the driving and driven bevel gears, and bearing mounting seats at both ends, with bearing lubrication oil passages inside. The main reducer housing also features a sealing harness window for the electronic locking differential wiring harness sealing lead-out and locating pin holes to ensure assembly accuracy. The mounting hole diameter for the sealing harness window can be 23.5mm, with an upper deviation of +0.1mm and a lower deviation of 0mm, and it has an interference fit with the wiring harness connector.

[0010] The main reduction gear input flange adopts a non-circular weight reduction structure and is equipped with four bolt mounting holes with a diameter of 11.2 mm and a pitch circle diameter of 92 mm. The left and right half shafts are set with different lengths according to the differential offset, preferably 341 mm and 316 mm respectively; splines are set at both ends of the half shafts, and the end facing the wheel assembly is provided with threads for nut tightening.

[0011] The bearing mounting diameter on both sides of the electronic locking differential is preferably 50mm, and the suitable torque is 4500N·m. The wheel-side assembly can also be equipped with an air inflation / deflation connector, the steering knuckle is equipped with a tapered hole with a large end diameter of 32mm and a tolerance zone of H7, the pitch circle diameter of the tire bolt mounting hole of the wheel hub can be 340mm, and the transmission ratio of the wheel-side reduction unit is preferably 3.8.

[0012] The axle housing can be made of Q355NE low-alloy high-strength structural steel, the main reducer housing can be made of QT400-18L ductile iron, the steering knuckle can be made of ZG25MnCrNiMo-E cast steel, the wheel hub can be made of 2A50 forged aluminum alloy, the front and rear covers can be made of ZL101A aluminum alloy, the driving bevel gear, driven bevel gear, sun gear and planetary gear can be made of 20Cr2Ni4A carburized steel, the sun gear shaft and the main reducer input flange can be made of 42CrMo, the bearings can be made of GCr15 steel that has been tempered at low temperature, and the fasteners can be made of 35CrMo and equipped with an end tooth anti-loosening structure.

[0013] The main reducer input shaft and both left and right half shafts are equipped with single-lip TC-type skeleton oil seals with springs. A dustproof secondary lip is installed on the outer side of the main lip of the TC-type skeleton oil seal. The wheel assembly is equipped with double TC-type skeleton oil seals. The oil seals can be made of hydrogenated nitrile rubber, and the O-rings for static sealing can be made of fluorosilicone rubber.

[0014] The preload of the main reducer bearing is preferably 0.05mm to 0.08mm, the tooth flank clearance of the driving and driven bevel gears is preferably 0.25mm to 0.28mm, and the starting torque of the main reducer assembly without the disc gear is preferably 2N·m to 3.5N·m. The single-sided braking torque of the hydraulic brake caliper is preferably not less than 1719N·m.

[0015] As an optional low-temperature traction control solution, the system also includes a low-temperature traction control component. This component includes a controller, an ambient temperature sensor, a left wheel speed sensor, and a right wheel speed sensor. The controller also receives vehicle speed signals and is electrically connected to the electronic locking differential. When the ambient temperature is not higher than a temperature threshold and the vehicle speed is not higher than a speed threshold, the controller calculates the relative wheel speed difference based on the left and right wheel speeds. When the relative wheel speed difference reaches the locking condition, the controller locks the electronic locking differential; when the relative wheel speed difference reaches the release condition or the vehicle speed exceeds the speed threshold, the lock is released. The release threshold is less than the locking threshold to create a control hysteresis.

[0016] Compared with the prior art, the beneficial effects of the present invention are that the bridge shell adopts a regular hexagonal main body and a segmented welded structure, forming a portal-type high passability profile, which reduces the amount of material used while ensuring bending load capacity and increasing the ground clearance under the bridge, which helps to reduce the risk of vehicles sinking and colliding on soft snow surfaces. In particular, low-temperature applicable materials are selected for the axle housing, main reducer housing, steering knuckle, gears, bearings and seals, and the bearing preload and gear clearance are matched at low temperature to ensure that the key load-bearing components maintain toughness under low temperature impact and that the transmission pair maintains reasonable clearance and low starting torque during cold start. In particular, the hydrogenated nitrile rubber oil seal with dustproof secondary lip, the double TC type wheel edge seal and the fluorosilicone rubber O-ring can maintain the sealing lip fit at low temperatures and prevent fine snow, ice dust and mud water from entering the main lip area, thereby improving the cleanliness of lubrication and braking components; In particular, the electronic locking differential can lock while the vehicle is in motion. Combined with the low temperature traction judgment logic, it can automatically or assistedly lock when the temperature is low and the speed difference between the left and right wheels reaches the set conditions. It also avoids frequent switching through backlash judgment, thus improving the traction response on icy and snowy roads. In particular, the wheel-side planetary reduction structure achieves speed reduction and torque increase at the wheel end. Combined with forged aluminum alloy wheel hubs, aluminum alloy front and rear covers, and non-circular weight-reducing flanges, it can reduce unsprung mass and low-temperature rotational inertia. In particular, the hydraulic braking assembly avoids the risk of pipeline blockage caused by moisture freezing in the air circuit, and provides braking reserve for heavy-duty polar conditions through a large unilateral braking torque. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the integrated high-passability drive front axle and wheel-side system for polar low-temperature environments according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the overall structure of the wheel assembly according to an embodiment of the present invention; Figure 3 This is a flowchart of the low-temperature escape judgment logic according to an embodiment of the present invention; In the diagram: 1, main reducer assembly; 2, differential; 3, brake caliper; 4, brake disc; 5, flange; 6, half shaft; 7, rear cover; 8, oil seal; 9, axle housing; 10, steering knuckle; 11, output shaft; 12, planetary gear; 13, support plate; 14, air inlet / outlet connector; 15, wheel hub; 16, front cover. Detailed Implementation

[0018] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0019] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0020] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0021] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly 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 of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0022] Please see Figure 1 As shown, this is an integrated high-traffic drive front axle and wheel-side system for polar cryogenic environments according to the present invention. The present invention provides an integrated high-traffic drive front axle and wheel-side system for polar cryogenic environments.

[0023] Example 1: Mechanical Structure of the Drive Front Axle and Wheel-Side System like Figure 1 As shown, the drive front axle and wheel-side system of this embodiment consists of an axle housing 9, a main reducer assembly 1, an electronic locking differential 2, a left half-shaft 6, a right half-shaft 6, wheel-side assemblies on both sides, and hydraulic brake assemblies on both sides. The main reducer assembly 1 is mounted in the middle of the axle housing 9. The electronic locking differential 2 is integrated with the main reducer assembly 1. The left and right half-shafts 6 extend outward from both sides of the axle housing 9 and connect to the wheel-side assemblies on both sides. This arrangement concentrates the main reducer, differential, half-shaft 6 support, wheel-side reduction, and brake mounting structures into a single assembly, reducing exposed connecting parts and potential failure points in low-temperature environments.

[0024] Specifically, the axle housing 9 adopts a segmented welded structure, formed by welding together a regular hexagonal main body, a left half-shaft 6-sleeve, a right half-shaft 6-sleeve, a brake caliper 3 mounting plate, and a support plate 13. The regular hexagonal main body forms the installation space for the main reducer assembly 1. Its polygonal cross-section can provide a larger bending section modulus with the same amount of material, while also facilitating the formation of a higher under-bridge space in the vertical direction. The left and right half-shaft 6-sleeves are coaxial with the regular hexagonal main body or arranged according to the differential 2 offset requirements. The brake caliper 3 mounting plate is used to fix the hydraulic brake caliper 3, and the support plate 13 is used to cooperate with the vehicle suspension or steering connection structure. The total length of the axle housing 9 is 423.2 mm; when the vehicle is under normal load, the lowest point of the axle housing 9 is 0.4 to 0.6 times the wheel radius above the ground relative to the wheel bearing surface.

[0025] Specifically, the main reducer housing adopts an integral casting structure. A cavity is formed in the middle of the main reducer housing to accommodate the driving bevel gear, driven bevel gear, and electronic locking differential 2, with bearing mounting seats at both ends. The main reducer housing has a lubrication passage connecting the bearing area and the gear oil area, allowing lubricating oil to enter the bearing area during vehicle movement and gear oil churning. A sealing wire harness window is provided on the outer side of the main reducer housing, with a mounting hole diameter of 23.5mm, an upper deviation of +0.1mm, and a lower deviation of 0mm. The wire harness connector is pressed into the mounting hole to form an interference seal. A locating pin hole is provided near the sealing wire harness window to ensure the assembly position of the main reducer housing with the axle housing 9 or the rear cover 7.

[0026] Specifically, the main reducer input flange 5 has a non-circular profile, with its periphery retaining only the load-bearing area required for torque transmission and bolt placement, thus minimizing wasted material. The main reducer input flange 5 has a splined hole or connecting hole in the center to mate with the input shaft, and four bolt mounting holes with a diameter of 11.2 mm on its periphery, located on a pitch circle with a diameter of 92 mm. Compared to a circular flange 5 of the same outer diameter, this non-circular structure reduces weight while meeting torque transmission requirements.

[0027] Specifically, the electronic locking differential 2 is housed within the main reducer housing, with bearings on both sides having a mounting diameter of 50mm to improve support rigidity and torque capacity. It is designed to handle a torque of 4500 N·m. The actuator wiring harness of the electronic locking differential 2 is led out through a sealed wiring harness window and can be locked and unlocked by the vehicle controller or an independent controller. When the electronic locking differential 2 is unlocked, it allows differential rotation of the left and right half-shafts 6; when locked, it restricts the speed difference between the left and right half-shafts 6, ensuring that drive torque is transmitted to the wheel with higher traction.

[0028] Specifically, the left and right half-shafts 6 are configured as two half-shafts 6 of different lengths, 341mm and 316mm respectively, based on the differential 2 offset. The inner spline of each half-shaft 6 connects to the output end of the electronic locking differential 2, and the outer spline connects to the wheel-side reduction unit or flange 5; the outer end is also threaded to restrict the axial movement of the flange 5 or connecting parts after the nut is installed. The middle of the half-shaft 6 is supported by a bearing, and an oil seal 8 is installed at the position where it passes through the axle housing 9.

[0029] like Figure 2 As shown, the wheel assembly includes a steering knuckle 10, a wheel hub 15, a wheel-side reduction unit, a front cover 16, an output shaft 11, and an air inlet / outlet connector 14. The steering knuckle 10 mates with the vehicle's steering or suspension components through a tapered bore with a large end diameter of 32 mm and a tolerance zone of H7. The wheel hub 15 has a disc-shaped structure, with tire bolt mounting holes arranged on a pitch circle with a diameter of 340 mm. The front cover 16 and the steering knuckle 10 or wheel hub 15 housing form a closed wheel-side lubrication chamber.

[0030] The wheel-side reduction unit is a planetary gear structure, including a sun gear, multiple planet gears 12, and a planet carrier, with a transmission ratio of 3.8. Power output from the half-shaft 6 is transmitted to the sun gear. The planet gears 12 mesh with the sun gear and their corresponding ring gears, driving the planet carrier to output power. The output shaft 11 transmits the reduced and increased torque power to the wheel hub 15. In other embodiments satisfying the same transmission relationship, the input, output, or fixed relationship of the sun gear, planet carrier, and ring gear can be adjusted according to the installation space. The inflation / deflation connector 14 communicates with the tire inflation / deflation channel and is used to connect to the vehicle's central inflation / deflation system or an external inflation device.

[0031] The hydraulic braking assembly includes a hydraulic brake caliper 3 and a brake disc 4. The hydraulic brake caliper 3 is fixed to a mounting plate, and the brake disc 4 is coaxially connected to the wheel hub 15 and rotates synchronously. During braking, the hydraulic brake caliper 3 clamps the brake disc 4 to generate braking torque. In this embodiment, the single-sided braking torque of the hydraulic brake caliper 3 is 1719 N·m. The hydraulic braking method reduces the risk of moisture in the compressed air freezing and causing blockage of valves or pipelines.

[0032] Example 2: Matching of Cryogenic Materials, Sealing, and Transmission Parameters This embodiment, based on the structure of Embodiment 1, performs low-temperature adaptability matching on the materials and fitting parameters of key components. The axle housing 9 is made of Q355NE low-alloy high-strength structural steel, the main reducer housing is made of QT400-18L ductile iron, and the steering knuckle 10 is made of ZG25MnCrNiMo-E cast steel. These materials are used to maintain the impact toughness, elongation, and yield strength of the load-bearing components under low-temperature conditions near -41℃ and ice ridge impact conditions. The wheel hub 15 is made of 2A50 forged aluminum alloy, and the front cover 16 and rear cover 7 are made of ZL101A aluminum alloy to reduce the weight of the wheel ends and the axle assembly.

[0033] The driving bevel gear, driven bevel gear, sun gear, and planetary gears 12 are made of 20Cr2Ni4A carburized steel, while the sun gear shaft and main input flange 5 are made of 42CrMo. The gears undergo carburizing, quenching, and tempering treatments to obtain a wear-resistant surface layer and a tough core. The bearings are made of GCr15 steel and undergo low-temperature tempering to reduce dimensional changes caused by the transformation of retained austenite at low temperatures. Fasteners are made of 35CrMo and feature end-tooth anti-loosening structures to reduce loosening under low-temperature vibration and impact.

[0034] A single-lip, spring-loaded TC-type skeleton oil seal 8 is installed at the input shaft of the main reducer, at the position where the left half-shaft 6 exits the axle housing 9, and at the position where the right half-shaft 6 exits the axle housing 9. Each TC-type skeleton oil seal 8 has a dustproof secondary lip on the outside of the main lip. The dustproof secondary lip first blocks fine snow, ice dust, and mud, while the main lip maintains the lubricating oil seal. The wheel-side assembly uses two TC-type skeleton oil seals 8 to form a series seal. The oil seals 8 are made of hydrogenated nitrile rubber, and the O-rings for static sealing are made of fluorosilicone rubber FS6265, ensuring that the seals still have the elasticity required for lip following at temperatures near -55℃.

[0035] When assembling the main reducer assembly 1, the bearing preload is controlled at 0.05mm to 0.08mm, and the tooth flank clearance of the driving and driven bevel gears is controlled at 0.25mm to 0.28mm. After completing the bearing preload and tooth flank clearance adjustment, the starting torque of the main reducer assembly 1 without the disc gear is tested, and the starting torque is controlled at 2N·m to 3.5N·m. The above parameters allow for reasonable clearance and resistance margins to accommodate low-temperature thermal shrinkage and increased lubricating oil viscosity.

[0036] By combining the aforementioned materials, seals, and parameters, the design specifications allow the total weight of the front drive axle to be kept below 70 kg, and the total weight of a single-side or corresponding wheel-end assembly to be kept below 65 kg. Furthermore, the system maintains acceptable starting torque under cold start conditions at -41°C. Specific weight and low-temperature performance can be adaptively adjusted based on vehicle load, tire specifications, and axle housing wall thickness.

[0037] Example 3: Low Temperature Escape Judgment Logic like Figure 3 As shown, this embodiment adds a low-temperature traction control component to the electronic locking differential 2. The low-temperature traction control component includes a controller, an ambient temperature sensor, a left wheel speed sensor, and a right wheel speed sensor. The controller acquires the ambient temperature T, left wheel speed nL, right wheel speed nR, and vehicle speed v through the vehicle bus or independent signal line, and outputs a locking command or a releasing command to the electronic locking differential 2.

[0038] The controller first determines whether the ambient temperature T is not higher than the temperature threshold T0 and whether the vehicle speed v is not higher than the speed threshold v0. If either condition is not met, the controller keeps the electronic locking differential 2 in the disengaged state; if both conditions are met, the controller calculates the relative wheel speed difference λ between the left and right wheels. The relative wheel speed difference λ can be calculated as λ=|nL-nR| / max(|nL|, |nR|, nmin), where nmin is the minimum reference wheel speed set to avoid the denominator being too small.

[0039] When the relative wheel speed difference λ is not less than the locking threshold λon and continues for a first set time ton, the controller sends a locking command to the electronic locking differential 2. After the electronic locking differential 2 locks, the controller continues to collect wheel speed and vehicle speed; when the relative wheel speed difference λ is not greater than the release threshold λoff and continues for a second set time toff, or when the vehicle speed v is higher than the speed threshold v0, the controller sends a release command. The release threshold λoff is less than the locking threshold λon, thus forming hysteresis and avoiding repeated locking and unlocking when the left and right wheel speeds fluctuate near the critical values.

[0040] In a simple example, the temperature threshold T0 is set to -20℃, the speed threshold v0 is set to 30km / h, the locking threshold λon is set to 0.20, the release threshold λoff is set to 0.08, the first setting duration ton is set to 0.5s, and the second setting duration tooff is set to 2s. The above values ​​are only for illustrating the judgment process and can be calibrated based on tire size, vehicle weight, and the allowable locking speed of the electronic locking differential 2.

[0041] This logic allows automatic locking only under low temperature and low speed conditions, and prioritizes disengaging the lock as vehicle speed increases. This utilizes the electronic locking differential 2 to improve torque transfer when one wheel slips, and also reduces the risk of impact on the transmission system caused by locking during high-speed cornering or on high-traction surfaces. The controller can also be set with a driver manual permission switch, so that the automatic locking function takes effect only after obtaining driver permission.

[0042] Example 4: Assembly and Working Process During assembly, first install the driving bevel gear, driven bevel gear, electronic locking differential 2, and bearings into the main reducer housing. Adjust the bearing preload and tooth backlash according to the set values, and test the starting torque. Then, install the left and right half-shafts 6 into the axle housing 9 and the output end of the differential 2. Install the TC-type skeleton oil seal 8 with a dustproof auxiliary lip at the position where the half-shafts 6 protrude from the axle housing 9. After the main reducer assembly 1 is installed in the middle of the axle housing 9, it is positioned by the locating pin hole and fixed by fasteners. The wiring harness of the electronic locking differential 2 is led out through the sealed wiring harness window.

[0043] The wheel assemblies on both sides are respectively installed at both ends of the axle housing 9, connecting the half shaft 6 to the wheel rim reduction unit. The wheel hub 15, output shaft 11, front cover 16, double TC type skeleton oil seal 8, brake disc 4, and hydraulic brake caliper 3 are then installed sequentially. After assembly, low-temperature gear lubricating oil suitable for low temperatures is injected into the main reducer cavity and the wheel rim lubrication cavity. Leakage checks are then performed on the sealing harness window, input shaft oil seal 8, half shaft 6 oil seal 8, and wheel rim oil seal 8.

[0044] When the vehicle is in motion, power is transmitted to the driving bevel gear via the main reduction input flange 5, which in turn drives the housing of the electronic locking differential 2 to rotate. In the disengaged state, the electronic locking differential 2 distributes power to the left and right half-shafts 6, which in turn drive the wheel-side reduction units on both sides. These reduction units reduce speed and increase torque before driving the wheel hub 15 and the wheels. If slippage occurs on one side of the wheel, the driver can manually control the electronic locking differential 2 or the logic in Embodiment 3 can be used to lock it. During braking, the hydraulic brake caliper 3 clamps the brake disc 4, causing the wheel hub 15 and the wheels to decelerate.

[0045] Those skilled in the art can adjust the axle housing wall thickness, the number of planetary gears on the wheel rim, the wheel rim transmission ratio, the sensor placement, and the control threshold without altering the basic concept of this invention; alternatively, low-temperature structural steel, low-temperature ductile iron, low-temperature rubber, or light alloy materials with equivalent performance can be used to replace the specific grades mentioned above. All such equivalent changes should fall within the scope of the technical concept of this invention.

[0046] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

[0047] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An integrated high-passability drive front axle and wheel-side system for polar low-temperature environments, characterized in that, include: Axle housing, main reducer assembly, electronic locking differential, left half shaft, right half shaft, two wheel assemblies disposed at both ends of the axle housing, and hydraulic braking components corresponding to the two wheel assemblies respectively; The axle housing includes a regular hexagonal body, a left half-shaft sleeve, a right half-shaft sleeve, a brake caliper mounting plate, and a support plate. The left half-shaft sleeve, the right half-shaft sleeve, the brake caliper mounting plate, and the support plate are respectively welded to the regular hexagonal body. The main reducer assembly is housed within the regular hexagonal body, the electronic locking differential is housed within the main reducer assembly, and the two output ends of the electronic locking differential are respectively connected to the two wheel assemblies via the left half-shaft and the right half-shaft; Each of the wheel rim assemblies includes a steering knuckle, a wheel hub, a wheel rim reduction unit, a front cover, and an output shaft. The wheel rim reduction unit includes a sun gear, planet gears, and a planet carrier. The left half shaft or the right half shaft is driven to the corresponding wheel rim reduction unit. The wheel rim reduction unit is driven to the wheel hub through the output shaft. The hydraulic braking assembly includes a hydraulic brake caliper mounted on the brake caliper mounting plate and a brake disc that rotates synchronously with the wheel hub.

2. The integrated high-passability drive front axle and wheel-side system for polar low-temperature environments according to claim 1, characterized in that, In response to installation on a vehicle and the wheels being under normal load, the lowest point of the axle housing is 0.4 to 0.6 times the wheel radius above the ground relative to the wheel support surface, and the total length of the axle housing is 423.2 mm.

3. The integrated high-passability drive front axle and wheel-side system for polar low-temperature environments according to claim 1, characterized in that, The main reducer assembly includes a main reducer housing, a driving bevel gear, a driven bevel gear, and a main reducer input flange; The main reducer housing has a cavity in the middle to accommodate the driving bevel gear and the driven bevel gear, bearing mounting seats at both ends, bearing lubrication oil passage inside, and a sealed wire harness window and a positioning pin hole corresponding to the wire harness of the electronic locking differential. The mounting hole diameter of the sealed wire harness window is 23.5mm, with an upper deviation of +0.1mm and a lower deviation of 0mm. The mounting hole is interference-fitted with the wire harness connector. The main input flange is a non-circular structure and has four bolt mounting holes with a diameter of 11.2 mm. The pitch circle diameter of each bolt mounting hole is 92 mm.

4. The integrated high-passability drive front axle and wheel-side system for polar low-temperature environments according to claim 1, characterized in that, The lengths of the left half-shaft and the right half-shaft are 341mm and 316mm respectively, and both ends of the left half-shaft and the right half-shaft are provided with splines; The end facing the corresponding wheel assembly is provided with threads for nut tightening; The bearings on both sides of the electronic locking differential have a mounting diameter of 50mm, and the adaptive torque of the electronic locking differential is 4500N·m.

5. The integrated high-passability drive front axle and wheel-side system for polar low-temperature environments according to claim 1, characterized in that, The wheel assembly also includes an inflation / deflation connector; The steering knuckle has a tapered hole with a large end diameter of 32mm and a tolerance zone of H7; the wheel hub has a tire bolt mounting hole pitch circle diameter of 340mm; the wheel-side reduction unit has a transmission ratio of 3.8; and the hydraulic brake caliper has a single-sided braking torque of not less than 1719 N·m.

6. The integrated high-passability drive front axle and wheel-side system for polar low-temperature environments according to claim 3, characterized in that, The axle housing is made of Q355NE low-alloy high-strength structural steel, the main reducer housing is made of QT400-18L ductile iron, the steering knuckle is made of ZG25MnCrNiMo-E cast steel, and the wheel hub is made of 2A50 forged aluminum alloy. The main reducer assembly also includes a rear cover. The front cover and the rear cover are both made of ZL101A aluminum alloy, and the driving bevel gear, the driven bevel gear, the sun gear and the planetary gear are all made of 20Cr2Ni4A carburized steel.

7. The integrated high-passability drive front axle and wheel-side system for polar low-temperature environments according to claim 3, characterized in that, The main reducer assembly also includes an input shaft connected to the main reducer input flange. A single-lip TC-type skeleton oil seal with a spring is provided at the input shaft, the left half-shaft and the right half-shaft respectively. A dustproof secondary lip is provided on the outer side of the main lip of the TC-type skeleton oil seal. Each of the wheel rim assemblies is equipped with two TC-type skeleton oil seals. The TC-type skeleton oil seals are made of hydrogenated nitrile rubber, and the O-rings for static sealing are made of fluorosilicone rubber.

8. The integrated high-passability drive front axle and wheel-side system for polar low-temperature environments according to claim 3, characterized in that, The bearings in the main reducer assembly are made of GCr15 steel that has undergone low-temperature tempering treatment. The bearing preload is 0.05mm to 0.08mm. The tooth flank clearance of the driving bevel gear and the driven bevel gear is 0.25mm to 0.28mm. The starting torque of the main reducer assembly without the disc gear is 2-3.5N·m.

9. The integrated high-passability drive front axle and wheel-side system for polar low-temperature environments according to claim 1, characterized in that, It also includes a low-temperature escape control component; The low-temperature escape control component includes a controller, an ambient temperature sensor, a left wheel speed sensor, and a right wheel speed sensor; The controller is electrically connected to the ambient temperature sensor, the left wheel speed sensor, the right wheel speed sensor, the vehicle speed signal interface, and the electronic locking differential.

10. The integrated high-passability drive front axle and wheel-side system for polar cryogenic environments according to claim 9, characterized in that, The controller is configured to: Obtain ambient temperature, left wheel speed, right wheel speed, and vehicle speed; When the ambient temperature is not higher than the temperature threshold and the vehicle speed is not higher than the speed threshold, calculate the relative wheel speed difference between the left wheel speed and the right wheel speed; When the relative wheel speed difference is not less than the locking threshold and continues to reach the first set time, the electronic locking differential is controlled to lock. When the relative wheel speed difference is not greater than the release threshold and continues to reach the second set time, or when the vehicle speed is higher than the speed threshold, the electronic locking differential is controlled to release the lock. Wherein, the release threshold is less than the lock threshold.

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