Integral drive axle structure for extra-heavy off-road vehicle

Abstract

The invention discloses an integral drive axle structure for an extra-heavy off-road vehicle, and belongs to the technical field of vehicle engineering and mechanical transmission, the integral drive axle structure comprises an axle housing assembly, and constant velocity universal joint assemblies, knuckle assemblies, hub assemblies and hub reduction gear assemblies which are symmetrically arranged on two sides, and the middle part of the axle housing assembly is connected with a main reduction gear assembly; the axle housing assembly comprises an integrally-formed integral axle housing body, a steering swing arm support is arranged above the middle of the axle housing body, an upper thrust rod support connector is further arranged in the middle of the axle housing body, a spiral spring mounting support, a shock absorber support and a lower thrust rod support connector are arranged on the two sides of the axle housing body, and the two ends of the axle housing body are connected with the steering knuckle assembly. The knuckle assembly is connected with the hub reduction gear assembly through the hub assembly. Through the integrally-formed axle housing, the geometric optimization support design and the multi-interface modularization scheme, the layout of an axle system is optimized, the number of assemblies is reduced, the weight is reduced, and the response speed and controllability of a vehicle are improved.

Description

Technical Field

[0001] The present invention relates to the field of vehicle engineering and mechanical transmission technology, and in particular to an integral drive axle structure for an ultra-heavy off-road vehicle. Background Art

[0002] In the field of ultra-heavy off-road vehicles, the drive axle is the core load-bearing and power transmission component. Its performance directly determines the vehicle's high load capacity, complex terrain passability, and long-term operational reliability. As the demand for vehicle load limits and off-road performance in special transportation, mining, and other fields continues to increase, traditional drive axle technology has exposed the following technical bottlenecks that need to be addressed: First, there are inherent flaws in structural strength and fatigue life. Traditional drive axles often utilize segmented welded or bolted axle housing structures. Under extreme off-road conditions (such as high impact loads, high torque, and asymmetric forces), welds or joints can easily become stress concentration points, causing deformation, cracking, and even failure of the axle housing. For example, when climbing a hill with a full load or traveling at high speed on rough roads, the axle housing experiences compound bending stresses far exceeding those experienced by conventional vehicles. Existing designs struggle to balance lightweighting with ultra-high strength requirements, making this a primary factor limiting vehicle reliability.

[0003] Second, space constraints and low system integration complicate the ultra-heavy off-road vehicle chassis, which must simultaneously accommodate a massive powertrain, multi-link suspension, hydraulic steering, and stabilizer mechanisms. Traditional drive axles utilize a decentralized "axle housing + external supports" design. Suspension supports (such as coil spring seats and thrust rod hinge points) must be welded or bolted to the exterior of the axle housing, significantly increasing radial dimensions. Power steering cylinder supports and shock absorber mounting points often rely on auxiliary brackets, which not only consume valuable space but also lead to system interference (such as collisions between the steering linkage and brake lines) due to cumulative assembly errors. Redundant designs in the power transmission paths of the main drive, wheel-end reducers, and steering knuckles result in transmission efficiency losses and excess weight. This fragmented layout forces compromises in vehicle design, even requiring increased chassis ground clearance to avoid interference, sacrificing vehicle center of gravity stability.

[0004] Third, the manufacturing and maintenance costs are high: on the manufacturing side, the multi-part assembled bridge housing requires high-precision tooling to ensure the spatial position tolerance of each support, and the production process involves a large number of welding and machining steps; on the maintenance side, the replacement of key components is extremely cumbersome. For example, replacing the steering knuckle requires removing the kingpin, separating the wheel-side reducer, and disconnecting multiple sets of connecting rods, which takes up to several hours; the oil drain holes and air vents of traditional bridge housings are hidden, and maintenance operations are difficult to access, increasing the risk of misoperation.

[0005] Fourth, the traditional drive axle structure lacks system adaptability and scalability. The interface standardization of the existing drive axle is low, making it difficult to adapt to different tonnage vehicle models or functional expansion requirements. For example, the suspension supports (such as coil spring seats) are designed with fixed dimensions and are not compatible with springs of different stiffness or air suspension upgrades; the steering arm installation structure is single, and adjusting the steering transmission ratio requires replacing the entire steering knuckle assembly; the thrust rod layout is limited by the support position, making it difficult to optimize the longitudinal force transmission path to suppress the brake nodding phenomenon. Summary of the Invention In response to the problems existing in the prior art, the present invention provides an integral drive axle structure for ultra-heavy off-road vehicles. Through an integrally formed high-strength bridge housing, a geometrically optimized support design, and a multi-interface modular solution, the layout of the axle system is optimized, the number of components of the drive axle structure is reduced, and the weight is reduced, thereby further improving the vehicle's response speed and maneuverability. This systematically overcomes the bottlenecks of the existing technology, improves the performance of ultra-heavy off-road vehicles, and optimizes costs.

[0006] The technical solutions of the present invention are as follows: In a first aspect of the present invention, an integral drive axle structure for an ultra-heavy off-road vehicle is provided, comprising an axle housing assembly and a constant velocity joint assembly, a steering knuckle assembly, a wheel hub assembly, and a wheel-side reducer assembly symmetrically arranged on both sides, wherein a main reducer assembly is connected to the middle portion of the axle housing assembly; The bridge housing assembly includes an integral bridge housing body formed in one piece, a steering swing arm support is provided above the middle of the bridge housing body, an upper thrust rod support interface and a steering power cylinder support are also provided in the middle of the bridge housing body, and coil spring mounting supports, shock absorber supports and lower thrust rod support interfaces are provided on both sides of the bridge housing body. Both ends of the bridge housing body are connected to the steering knuckle assembly, and the steering knuckle assembly is connected to the wheel-side reducer assembly through the wheel hub assembly. In some embodiments of the present invention, the bridge housing assembly is manufactured using high-strength cast steel. In some embodiments of the present invention, a final reducer mounting surface is provided at the front middle portion of the axle housing body, and the final reducer assembly is connected to the final reducer mounting surface by a plurality of bolts; A vent is provided above the middle of the bridge housing body near the steering arm support, a bridge bag is provided at the rear middle of the bridge housing body, two upper thrust rod supports and two steering power cylinder supports are symmetrically distributed above the bridge bag, a refueling hole and an oil drain hole are provided on the bridge bag, the refueling hole is provided in the middle of the bridge bag, and the oil drain hole is provided at the lower part of the bridge bag.

[0007] In some embodiments of the present invention, an oil groove and a positioning pin hole are provided inside the bridge housing body; and the cross section of the bridge housing body is a rectangular structure. In some embodiments of the present invention, steering knuckle support seats are provided at both ends of the axle housing body, and the axle housing body is connected to the steering knuckle assembly via the steering knuckle support seats; The steering knuckle support seat is provided with two connecting structures, and the two connecting structures are respectively connected to the steering knuckle assembly through an upper kingpin and a lower kingpin. In some embodiments of the present invention, steering limit blocks are further provided at both ends of the bridge housing body near the steering knuckle support seat. In some embodiments of the present invention, the constant velocity joint assembly is disposed between the axle housing body and the steering knuckle assembly, and the wheel reducer assembly is connected to the main reducer assembly via the constant velocity joint assembly. In some embodiments of the present invention, the coil spring mounting support is configured as a truncated cone structure. In some embodiments of the present invention, the steering swing arm support is configured as a structure combining a seat hole and a tapered hole. In some embodiments of the present invention, the upper thrust rod support interface is configured as a U-shaped structure.

[0008] One or more technical solutions of the present invention have the following beneficial effects: This invention systematically overcomes the long-standing technical bottlenecks in the field of drive axles for ultra-heavy off-road vehicles through the innovative design of a one-piece high-strength axle housing, a multi-dimensional integrated interface, and a modular transmission link. It achieves all-round breakthroughs in performance, efficiency, and cost, including: It improves the structural reliability under extreme working conditions. It adopts a one-piece high-strength cast steel bridge shell with a rectangular cross-section structure, effectively eliminating the stress concentration risk of traditional welded bridge shells and improving the bending section modulus. At the same time, a U-shaped upper thrust rod support is set to convert the longitudinal force into surface load, thereby improving the tensile and compressive limit loads. In addition, it is combined with a truncated cone-shaped coil spring support, and its internal pin shaft hole is precisely guided to eliminate the bridge shell buckling caused by spring unbalanced load. The steering knuckle support seat and the limit block are cast as one piece, and the kingpin span is increased, thereby enhancing the ability to resist lateral impact.

[0009] At the same time, space utilization is improved and a lightweight drive axle structure is achieved. Vertical space is compressed. Specifically, the coil spring and shock absorber mounts are sunken to reduce installation height, and the tapered holes of the steering arm mounts are recessed into the top surface of the axle housing to save radial space. Vertical integration is also achieved. The final reducer is mounted in front to free up space in the axle housing. The U-shaped upper thrust rod mount is located in the axle housing to reduce protrusions. The oil filler, drain, and vent holes are centrally located to reduce maintenance access. The drive chain is further streamlined, with the constant velocity universal joint assembly directly connected to the final reducer assembly and the wheel reducer assembly, eliminating the intermediate bearing. This effectively reduces the weight of the transmission components, and the reduced inertia significantly improves the vehicle's dynamic response. As a result, the overall volume of the drive axle structure is reduced, ground clearance is increased, and the vehicle's center of gravity is lowered, achieving a qualitative improvement in cross-terrain maneuverability.

[0010] In addition, the bridge housing body adopts one-piece casting to eliminate welding and machining processes, improve the yield rate, simplify the assembly and positioning operations of multiple structures, and improve assembly accuracy. The steering arm support is set to a combination of seat hole and tapered hole structure design, which supports the replacement of the arm without dismantling the bridge, reducing operating hours and facilitating maintenance.

[0011] In addition, the one-piece bridge housing integrates multiple types of functional interfaces and has good expansion capabilities. By adjusting the interface parameters, a single architecture can cover multiple models, thereby improving practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic front view of an integral drive axle structure for an ultra-heavy off-road vehicle provided in Example 1 of the present invention; Figure 2 This is a schematic top view of an integral drive axle structure for an ultra-heavy off-road vehicle provided in Example 1 of the present invention; Figure 3 This is a schematic front view of the axle housing assembly structure provided in Example 1 of the present invention; Figure 4 This is a schematic top view of the bridge housing assembly structure provided in Example 1 of the present invention.

[0013] In the figure: 1. Wheel-side reducer assembly; 2. Wheel hub assembly; 3. Steering knuckle assembly; 4. Constant velocity joint assembly; 5. Main reducer assembly; 6. Axle housing assembly; 601. Axle housing body; 602. Steering arm support; 603. Coil spring mounting support; 604. Shock absorber support; 605. Upper thrust rod support interface; 606. Upper kingpin; 607. Lower kingpin; 608. Lower thrust rod support interface; 609. Vent; 610. Power steering cylinder support; 611. Oil filling hole; 612. Oil drain hole; 613. Main reducer mounting surface; 614. Axle package; 615. Steering knuckle support seat; 616. Steering limit block. DETAILED DESCRIPTION

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0015] Example 1 In a typical embodiment of the present invention, an integrated drive axle structure for an ultra-heavy off-road vehicle is proposed, comprising an axle housing assembly 6 and a constant velocity joint assembly 4, a steering knuckle assembly 3, a wheel hub assembly 2, and a wheel-side reducer assembly 1 symmetrically arranged on both sides. A main reducer assembly 5 is connected to the middle portion of the axle housing assembly 6. The bridge housing assembly 6 includes an integrally formed integral bridge housing body 601, a steering swing arm support 602 is provided above the middle of the bridge housing body 601, an upper thrust rod support interface 605 and a steering power cylinder support 610 are also provided in the middle of the bridge housing body 601, and coil spring mounting supports 603, shock absorber supports 604 and lower thrust rod support interfaces 608 are provided on both sides of the bridge housing body 601. Both ends of the bridge housing body 601 are connected to the steering knuckle assembly 3, and the steering knuckle assembly 3 is connected to the wheel-side reducer assembly 1 through the wheel hub assembly 2.

[0016] With such a configuration, multiple functional interfaces are integrated through the one-piece bridge housing body 601, such as the steering arm support 602, the coil spring mounting support 603, and the upper thrust rod support interface 605, thereby improving space utilization, eliminating radial interference caused by traditional external supports, and increasing the chassis ground clearance. At the same time, the symmetrically arranged wheel-side reducer assembly 1 and the steering knuckle assembly 3 form a linear power transmission chain, thereby improving transmission efficiency and reducing the overall weight of the drive axle structure.

[0017] Furthermore, the axle housing assembly 6 is manufactured from high-strength cast steel. By using high-strength cast steel, the bending section modulus of the axle housing body 601 is increased. Under overload conditions, the maximum stress is effectively reduced compared to axle housings of conventional structures, thereby increasing fatigue life.

[0018] Furthermore, a main reducer mounting surface 613 is provided in the front middle portion of the axle housing body 601, and the main reducer assembly 5 is connected to the main reducer mounting surface 613 by a plurality of bolts; A vent hole 609 is provided at the upper middle portion of the bridge housing body 601 near the steering arm support 602. A bridge bag 614 is provided at the rear middle portion of the bridge housing body 601. Two upper thrust rod supports and two steering assist cylinder supports 610 are symmetrically distributed above the bridge bag 614. A refueling hole 611 and an oil drain hole 612 are provided on the bridge bag 614. The refueling hole 611 is provided at the middle portion of the bridge bag 614, and the oil drain hole 612 is provided at the lower portion of the bridge bag 614.

[0019] With this arrangement, the main reducer assembly 5 can be stably connected to the bridge housing body 601, improving assembly accuracy. At the same time, the detachable connection can improve the convenience of maintenance, and the upper and lower layout of the oil filling hole 611 and the oil drain hole 612 plus the top centralized design of the bridge package 614 further shorten the maintenance operation time.

[0020] Furthermore, an oil groove and a positioning pin hole are provided inside the axle housing body 601; and the cross section of the axle housing body 601 is a rectangular structure. With this arrangement, the internal oil groove of the bridge housing body 601 forms a self-circulating lubrication system, which extends the life of the wheel end seal, and the rectangular cross-section bridge housing increases its torsional rigidity, which can effectively suppress the deformation of the bridge housing under off-road conditions and improve the load-bearing capacity and service life.

[0021] Furthermore, the two ends of the axle housing body 601 are provided with steering knuckle support seats 615, and the axle housing body 601 is connected to the steering knuckle assembly 3 through the steering knuckle support seats 615; The steering knuckle support seat 615 is provided with two connection structures, and the two connection structures are connected to the steering knuckle assembly 3 through the upper main pin 606 and the lower main pin 607 respectively. With this arrangement, the steering knuckle support seat 615 forms a closed force loop by connecting the upper kingpin 606 and the lower kingpin 607, thereby improving the ability to resist lateral impact loads, enhancing the connection strength and ensuring transmission stability.

[0022] Furthermore, a steering stop block 616 is provided at both ends of the axle housing body 601 near the steering knuckle support seat 615. In this way, the integrally cast steering stop block 616 can avoid the risk of bolt loosening and improve the control accuracy of the steering angle.

[0023] Furthermore, the constant velocity joint assembly 4 is disposed between the axle housing body 601 and the steering knuckle assembly 3, and the wheel reducer assembly 1 is connected to the final reducer assembly 5 via the constant velocity joint assembly 4. This arrangement directly connects the final reducer and wheel reducer, eliminating intermediate support bearings, reducing transmission chain components, and lowering inertia, thereby improving the vehicle's dynamic response speed.

[0024] Furthermore, the coil spring mounting support 603 is configured as a truncated cone structure. The coil spring mounting support is configured in this way. The truncated cone structure is designed with a pin hole inside, which can be adjusted according to different load requirements to achieve optimal suspension performance.

[0025] Furthermore, the steering arm support 602 is configured as a seat hole and a tapered hole combination structure. Thus, the steering arm support 602 is designed as a seat hole and a tapered hole combination structure, allowing the replacement of steering arms of different specifications, thereby improving the convenience of maintenance. Furthermore, the upper thrust rod support interface 605 is configured as a U-shaped structure. Thus, the upper thrust rod support adopts a U-shaped structure design, has strong torsion resistance, adapts to a variety of thrust rod layouts, fits the axle contour, and reduces space occupation.

[0026] This invention systematically overcomes the long-standing technical bottlenecks in the field of drive axles for ultra-heavy off-road vehicles through the innovative design of a one-piece high-strength axle housing, a multi-dimensional integrated interface, and a modular transmission link. It achieves all-round breakthroughs in performance, efficiency, and cost, including: It improves the structural reliability under extreme working conditions. It adopts a single-piece high-strength cast steel bridge shell with a rectangular cross-section structure, effectively eliminating the stress concentration risk of traditional welded bridge shells and improving the bending section modulus. At the same time, a U-shaped upper thrust rod support interface 605 is set to convert the longitudinal force into surface load, thereby improving the tensile and compressive limit loads. In addition, it is combined with a truncated cone-shaped coil spring mounting support 603, whose internal pin shaft hole is precisely guided to eliminate the bridge shell buckling caused by spring unbalanced load. The steering knuckle support seat 615 and the limit block are cast as one piece, and the kingpin span is increased, thereby enhancing the ability to resist lateral impact.

[0027] At the same time, space utilization is improved and a lightweight drive axle structure is achieved. Vertical space is compressed. Specifically, the coil spring mounting bracket 603 and the shock absorber bracket 604 are sunken to reduce installation height. The steering arm bracket 602 features a tapered hole embedded in the top surface of the axle housing, saving radial space. Vertical integration is also achieved. The final reducer mounting surface 613 is positioned forward to free up space for the axle housing 614. The U-shaped upper thrust rod bracket is located within the axle housing 614 to reduce protrusions. The oil filler hole 611, oil drain hole 612, and air vent 609 are centrally located to reduce maintenance access. The drive chain is further streamlined. The constant velocity universal joint assembly 4 is directly connected to the final reducer assembly 5 and the wheel reducer assembly 1, eliminating the intermediate bearing. This effectively reduces the weight of the transmission components, and the reduced inertia significantly improves the vehicle's dynamic response. As a result, the overall volume of the drive axle structure is reduced, ground clearance is increased, and the vehicle's center of gravity is lowered, achieving a qualitative improvement in its ability to navigate complex terrain.

[0028] In addition, the bridge housing body 601 adopts an integrated casting to eliminate welding and machining processes, improve the yield rate, simplify the assembly and positioning operations of multiple structures, and improve assembly accuracy. The steering arm support 602 is set to a seat hole and a tapered hole combined structure design to support the replacement of the arm without dismantling the bridge, reducing operating hours and facilitating maintenance.

[0029] In addition, the integrated bridge housing body 601 integrates multiple types of functional interfaces and has good expansion capabilities. By adjusting the interface parameters, a single architecture can be used to cover multiple vehicle models, thereby improving practicality.

[0030] Although the above describes the specific embodiments of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without any creative work are still within the scope of protection of the present invention.

Claims

1. An integral drive axle structure for an ultra-heavy off-road vehicle, characterized in that: The structure includes an axle housing assembly and a constant velocity universal joint assembly, a steering knuckle assembly, a wheel hub assembly, and a wheel-side reducer assembly symmetrically arranged on both sides. The middle part of the axle housing assembly is connected to the main reducer assembly. The bridge housing assembly includes an integral bridge housing body formed in one piece, a steering swing arm support is provided above the middle of the bridge housing body, an upper thrust rod support interface and a steering power cylinder support are also provided in the middle of the bridge housing body, and coil spring mounting supports, shock absorber supports and lower thrust rod support interfaces are provided on both sides of the bridge housing body. Both ends of the bridge housing body are connected to the steering knuckle assembly, and the steering knuckle assembly is connected to the wheel-side reducer assembly through the wheel hub assembly.

2. The integrated drive axle structure for an ultra-heavy off-road vehicle according to claim 1, characterized in that: The bridge housing assembly is manufactured by high-strength cast steel.

3. The integrated drive axle structure for an ultra-heavy off-road vehicle according to claim 1, characterized in that: A main reducer mounting surface is provided in the front middle portion of the axle housing body, and the main reducer assembly is connected to the main reducer mounting surface by a plurality of bolts; A vent is provided above the middle of the bridge housing body near the steering arm support, a bridge bag is provided at the rear middle of the bridge housing body, two upper thrust rod supports and two steering power cylinder supports are symmetrically distributed above the bridge bag, a refueling hole and an oil drain hole are provided on the bridge bag, the refueling hole is provided in the middle of the bridge bag, and the oil drain hole is provided at the lower part of the bridge bag.

4. The integrated drive axle structure for an ultra-heavy off-road vehicle according to claim 1, characterized in that: An oil groove and a positioning pin hole are provided inside the axle housing body; and the cross section of the axle housing body is a rectangular structure.

5. The integrated drive axle structure for an ultra-heavy off-road vehicle according to claim 1, characterized in that: Steering knuckle support seats are provided at both ends of the axle housing body, and the axle housing body is connected to the steering knuckle assembly through the steering knuckle support seats; The steering knuckle support seat is provided with two connecting structures, and the two connecting structures are respectively connected to the steering knuckle assembly through an upper kingpin and a lower kingpin.

6. The integrated drive axle structure for an ultra-heavy off-road vehicle according to claim 5, characterized in that: Steering limit blocks are also provided at positions of both ends of the axle housing body close to the steering knuckle support seat.

7. The integrated drive axle structure for an ultra-heavy off-road vehicle according to claim 1, characterized in that: The constant velocity universal joint assembly is arranged between the axle housing body and the steering knuckle assembly, and the wheel-side reducer assembly is connected to the main reducer assembly through the constant velocity universal joint assembly.

8. The integrated drive axle structure for an ultra-heavy off-road vehicle according to claim 1, characterized in that: The coil spring mounting support is configured as a truncated cone structure.

9. The integrated drive axle structure for an ultra-heavy off-road vehicle according to claim 1, characterized in that: The steering swing arm support is configured as a seat hole and a tapered hole combined structure.

10. The integrated drive axle structure for an ultra-heavy off-road vehicle according to claim 1, characterized in that: The upper thrust rod support interface is configured as a U-shaped structure.

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