Aluminum alloy front auxiliary frame
Through the low-pressure casting and extrusion molding process of the aluminum alloy front subframe, combined with welding and bolt connection, the problems of high production cost and high maintenance cost of the existing aluminum alloy front subframe are solved, and lightweight and corrosion resistance are improved.
Patent Information
- Application Number
- CN202511018413.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-23
- Publication Date
- 2025-09-19
AI Technical Summary
The existing aluminum alloy front subframe has high production costs, heavy weight, and high maintenance costs, and cannot effectively achieve lightweight and corrosion resistance.
The front crossbeam, rear crossbeam and longitudinal beam structure are made of aluminum alloy, combined with low-pressure casting and extrusion molding processes. The design is simple and versatile, and the welding and bolt connections reduce the number of parts and mold requirements.
It achieves a significant lightweight effect, reduces production and maintenance costs, and improves corrosion resistance and overall strength.
Smart Images
Figure CN120664010A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of automobile parts, and in particular to an aluminum alloy front subframe. Background Art
[0002] The front subframe is a key structural component of the modern automobile chassis. It is responsible for connecting the suspension system (such as control arms, steering gear, stabilizer bar), powertrain (engine, motor, etc.) to the body-in-white, and for transmitting loads, isolating vibrations and noise.
[0003] High-strength steel remains the mainstream material for front subframes. While it offers low cost and high strength, it also results in high finished weight, a high number of parts, and complex manufacturing processes. Magnesium alloy subframes are lighter than aluminum alloys of the same volume, but corrosion resistance remains a challenge. Aluminum alloy subframes are increasingly popular in mid- to high-end vehicles focused on lightweighting. They can accommodate complex mounting points, brackets, or even the entire subframe, offering greater design freedom and the ability to integrate multiple functions. They offer significant weight reduction (approximately 30-50% lighter than steel) and excellent corrosion resistance. Currently, aluminum alloy front subframes are typically cast or welded, and to achieve lightweighting, they are typically hollow. Casting these frames requires numerous molds, resulting in high casting costs, while welded frames lack the strength they need. Furthermore, damage to either frame type typically requires complete replacement, leading to high repair costs. Summary of the Invention
[0004] The present invention aims to address the corresponding deficiencies of the prior art and provide an aluminum alloy front subframe having a simple structure, high versatility, significant lightweighting effect, and reduced cost.
[0005] The purpose of the present invention is achieved by adopting the following scheme: an aluminum alloy front subframe, comprising a front crossbeam, a rear crossbeam and a longitudinal beam made of aluminum alloy, the left and right ends of the front crossbeam and the rear crossbeam are respectively connected and fixed by longitudinal beams, the space between the front and rear crossbeams and the longitudinal beams is the clearance space of the powertrain, the left and right ends of the front crossbeam are provided with front body connection points, the oblique side surfaces of the left and right ends of the front crossbeam are provided with obliquely extending front control arm mounting brackets, the center of the rear side surface of the front crossbeam is provided with a rearward extending front cantilever mounting bracket, the left and right sides of the rear crossbeam are provided with rear body connection points, and the rear body A rear cantilever mounting bracket is provided on the upper end face of the connection point, and the upper and lower ends of the longitudinal beam are extended obliquely upward and are respectively connected and fixed to the front cross beam and the rear cross beam. A rear control arm mounting bracket extending to the left is provided in the middle section of the left side face of the left longitudinal beam, and a rear control arm mounting bracket extending to the right is provided in the middle section of the right side face of the right longitudinal beam. Two steering gear mounting points are provided in the front section of the upper end face of the longitudinal beam, and a stabilizer bar mounting point is provided at the lower end of the lower end face of the longitudinal beam. The front cross beam is cast as one piece, and the longitudinal beam and the rear cross beam are extruded hollow structures. The front end of the longitudinal beam is welded to the welding joint of the front cross beam.
[0006] A plurality of reinforcing ribs are provided at the bottom end of the front cross beam.
[0007] I-shaped reinforcement ribs are provided in the inner cavities of the longitudinal beam and the rear cross beam.
[0008] The rear body connection points at the left and right ends of the rear cross beam are cellular rib structures.
[0009] The rear suspension mounting bracket is connected and fixed to the rear cross beam by bolts.
[0010] The front suspension mounting bracket and the front cross beam are integrally cast.
[0011] The rear control arm mounting bracket is welded to the longitudinal beam, and the welding connection of the rear control arm mounting bracket is a "C"-shaped structure.
[0012] The front cross beam is formed by low-pressure casting.
[0013] The wall thickness of the extruded portion of the longitudinal beam and the rear cross beam is 3.5 mm, and the thickness of the reinforcing ribs in the cavities of the longitudinal beam and the rear cross beam is 4 mm.
[0014] The steering gear mounting point and the stabilizer bar mounting point are formed by welding aluminum threaded sleeves.
[0015] The advantages of this invention are that, compared to a steel front subframe, it can reduce weight, lower fuel and power consumption, be more corrosion-resistant, and require fewer welded parts. The front crossbeam is formed using low-pressure casting, eliminating the need for a sand core structure, preventing sand core gassing, and reducing harmful gases generated by sand core resin during casting. This eliminates the need for waste sand disposal and solid pollution, resulting in improved environmental benefits. Furthermore, the rear half of the subframe utilizes a profiled structure, maintaining a consistent cross-sectional shape among the main beams that comprise the frame-type subframe. This reduces mold design costs and the number of molds required. The hollow profile further reduces weight. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 A top view of the present invention; Figure 2 It is a bottom view of the present invention; Figure 3 It is a side view of the present invention; Figure 4 It is a front view of the present invention; Figure 5 It is the cross-sectional view in the direction of A; Figure 6 It is the cross-sectional view in the direction of B; Figure 7 It is a C-section view. DETAILED DESCRIPTION
[0017] like Figures 1 to 7As shown, an aluminum alloy front subframe includes a front crossbeam 1, a rear crossbeam 6 and a longitudinal beam 4 made of aluminum alloy. The left and right ends of the front crossbeam 1 and the rear crossbeam 6 are respectively connected and fixed by the longitudinal beam 4. The space between the front and rear crossbeams and the longitudinal beam 6 is the makeshift space for the powertrain. The left and right ends of the front crossbeam 1 are provided with front body connection points 2, the oblique side surfaces of the left and right ends of the front crossbeam 1 are provided with obliquely extending front control arm mounting brackets 8, and the center of the rear side surface of the front crossbeam 1 is provided with a rearward extending front cantilever mounting bracket 11. The front suspension mounting bracket 11 is integrally cast with the front crossbeam 1, so that the front crossbeam 1 is an "M"-shaped frame. The "M"-shaped frame can be destroyed first from the recessed part during a collision, and there is a buffer space before the force is transmitted to the rear section, which can improve the safety factor to a certain extent. Rear body connection points 5 are located on the left and right sides of the rear crossbeam 6. Rear suspension arm mounting brackets 10 are located on the upper end surfaces of these points. The rear body connection points 5 on both ends of the rear crossbeam 6 feature a cellular rib structure, enhancing the strength and rigidity of the mounting location while also transmitting force and absorbing energy, improving the overall energy absorption efficiency of the component. The rear suspension mounting brackets 10 are bolted to the rear crossbeam 6. The subframe can be freely switched between two-wheel drive (without a motor) and four-wheel drive (with a motor) depending on whether the rear suspension brackets are installed. The left and right suspensions utilize a symmetrical structure, which reduces error prevention and features chamfered corners to prevent scratching of the bushings during press-fitting. The upper and lower ends of the longitudinal beam 4 extend obliquely upward and are respectively connected to the front and rear crossbeams 1 and 6. A rear control arm mounting bracket 9 extending leftward is located in the middle section of the left side of the left longitudinal beam 4, while a rear control arm mounting bracket 9 extending rightward is located in the middle section of the right side of the right longitudinal beam 4. The rear control arm mounting brackets 9 are welded to the longitudinal beam 4, forming a "C"-shaped connection. The contoured profile can effectively increase the welding area and further ensure the welding strength. At the same time, the structure can be directly formed by extrusion without machining, which can improve material utilization and reduce processing time. Two steering gear mounting points 3 are set on the front section of the upper end face of the longitudinal beam 4, and a stabilizer bar mounting point 7 is set at the lower end of the lower end face of the longitudinal beam 4. The steering gear mounting point 3 and the stabilizer bar mounting point 7 are welded by aluminum threaded sleeves, and the mounting point ring weld can ensure stronger strength. At the same time, the reinforcing ribs on the left and right longitudinal beams can play an auxiliary positioning role, which is beneficial to ensure the welding size. The front crossbeam 1 is formed by low-pressure casting as an integral whole, and a plurality of reinforcing ribs are set at the bottom end of the front crossbeam 1 to ensure the strength of the front crossbeam 1. The solid structure of the front crossbeam 1 can reduce casting defects and improve a certain internal quality. At the same time, it eliminates the design and manufacture of sand cores, can effectively reduce the harmful gases generated during the manufacture of sand cores, and can also reduce the cost of sand core quality control, thereby improving production efficiency to a certain extent. The longitudinal beam 4 and rear crossbeam 6 are extruded hollow structures, with the front end of the longitudinal beam 4 welded to the weld 12 of the front crossbeam 1. I-shaped reinforcement ribs are installed within the inner cavities of the longitudinal beam 4 and rear crossbeam 6. The cross-sections of the longitudinal beam and rear crossbeam are identical, requiring only one set of molds to ensure product cost-effectiveness.The wall thickness of the extruded portion of the longitudinal beam 4 and the rear cross beam 6 is 3.5 mm, and the thickness of the reinforcing ribs in the cavities of the longitudinal beam 4 and the rear cross beam 6 is 4 mm, thus achieving lightweight while meeting the requirements of strength.
[0018] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications made to the present invention by those skilled in the art without departing from the spirit of the present invention shall fall within the scope of protection of the present invention.
Claims
1. An aluminum alloy front subframe, comprising a front crossbeam (1), a rear crossbeam (6) and a longitudinal beam (4) made of aluminum alloy, wherein the left and right ends of the front crossbeam (1) and the rear crossbeam (6) are respectively connected and fixed by the longitudinal beam (4), and the space between the front and rear crossbeams and the longitudinal beam (6) is a space for the powertrain, and is characterized in that: The front crossbeam (1) is provided with a front vehicle body connection point (2) at both ends, and oblique side surfaces of the left and right ends of the front crossbeam (1) are provided with obliquely extending front control arm mounting brackets (8), and a rearwardly extending front cantilever mounting bracket (11) is provided at the center of the rear side surface of the front crossbeam (1). The rear vehicle body connection points (5) are provided on both sides of the rear crossbeam (6), and a rear cantilever mounting bracket (10) is provided on the upper end surface of the rear vehicle body connection point (5). The upper and lower ends of the longitudinal beam (4) are obliquely extended upwards and are respectively connected and fixed to the front crossbeam (1) and the rear crossbeam (6). A rear control arm mounting bracket (9) extending to the left is provided in the middle section of the left side longitudinal beam (4), a rear control arm mounting bracket (9) extending to the right is provided in the middle section of the right side longitudinal beam (4), two steering gear mounting points (3) are provided in the front section of the upper end face of the longitudinal beam (4), and a stabilizer bar mounting point (7) is provided at the lower end of the lower end face of the longitudinal beam (4). The front crossbeam (1) is integrally cast, the longitudinal beam (4) and the rear crossbeam (6) are extruded hollow structures, and the front end of the longitudinal beam (4) is welded to the welding port (12) of the front crossbeam (1).
2. The aluminum alloy front subframe according to claim 1, characterized in that: A plurality of reinforcing ribs are provided at the bottom end of the front cross beam (1).
3. The aluminum alloy front subframe according to claim 1, characterized in that: I-shaped reinforcement ribs are provided in the inner cavities of the longitudinal beam (4) and the rear cross beam (6).
4. The aluminum alloy front subframe according to claim 1, characterized in that: The rear body connection points (5) at the left and right ends of the rear cross beam (6) are cellular rib structures.
5. The aluminum alloy front subframe according to claim 1, characterized in that: The rear suspension mounting bracket (10) is connected and fixed to the rear cross beam (6) via bolts.
6. The aluminum alloy front subframe according to claim 1, characterized in that: The front suspension mounting bracket (11) and the front crossbeam (1) are integrally cast.
7. The aluminum alloy front subframe according to claim 1, characterized in that: The rear control arm mounting bracket (9) is welded to the longitudinal beam (4), and the welded connection of the rear control arm mounting bracket (9) is a "C"-shaped structure.
8. The aluminum alloy front subframe according to claim 1, characterized in that: The front cross beam (1) is formed by low-pressure casting.
9. The aluminum alloy front subframe according to claim 1, characterized in that: The wall thickness of the extruded portion of the longitudinal beam (4) and the rear cross beam (6) is 3.5 mm, and the thickness of the reinforcing ribs in the cavities of the longitudinal beam (4) and the rear cross beam (6) is 4 mm.
10. The aluminum alloy front subframe according to claim 1, characterized in that: The steering gear mounting point (3) and the stabilizer bar mounting point (7) are formed by welding aluminum threaded sleeves.