Cutting machining method for anti-vibration bracket of electric vehicle and anti-vibration bracket

Abstract

The invention relates to the technical field of metal machining, new energy vehicle parts and the like in a material cutting mode, and provides a cutting machining method of an electric vehicle shockproof bracket and the shockproof bracket. The bracket machining base material is blanked and cut, and the bracket base body comprising the first mounting part, the second mounting part and the damping supporting part is obtained; carrying out tempering treatment to remove stress and improve deformation resistance; and through clamping of a clamp, single-face independent cutting is sequentially executed to form a flat main body face, and multi-face synchronous cutting is executed to form a connecting curved face. The cutting head of the finish machining cutting machine tool is controlled to continuously move in the three-dimensional space by setting the tool path strategy, high-precision machining, structural curved surface continuity and surface quality consistency are achieved, and the mechanical stability and assembly adaptability of the bracket are improved.

Description

Technical Field

[0001] The present invention relates to the technical fields of metal processing by material removal methods, new energy vehicle components, etc., and particularly relates to a cutting method for an electric vehicle shock-absorbing bracket and a shock-absorbing bracket. Background Art

[0002] With the rapid development of the new energy vehicle industry, the vehicle chassis system has put forward higher requirements for the lightweight, structural strength and seismic performance of structural components. Among them, the shock-absorbing bracket, as a key component connecting the chassis and the suspension system, undertakes the functions of transmitting the vehicle body load, absorbing shock and maintaining structural stability. Such brackets are usually processed from high-strength aluminum alloy or lightweight alloy materials, and are required to have complex spatial curved surface structures and high-precision connecting surfaces. In the prior art, the processing methods of shock-absorbing brackets mainly include the following two: one is to perform multi-angle processing on the bracket through multiple clamping and multi-station cutting processes, and the other is to perform local machining and trimming after die forging or casting. However, these traditional methods often have problems such as difficult to unify processing accuracy, discontinuous curved surface connection, insufficient stress release, easy deformation of the structure, large topography error in the connection area, and uneven surface roughness in practical applications.

[0003] In summary, the existing processing technologies for electric vehicle shock-absorbing brackets have technical problems such as difficult to unify processing accuracy, discontinuous curved surface connection, insufficient stress release, easy deformation of the structure, large topography error in the connection area, and uneven surface roughness. Summary of the Invention

[0004] Aiming at the deficiencies of the above-mentioned prior art, the present invention provides a cutting method for an electric vehicle shock-absorbing bracket and a shock-absorbing bracket, so as to unify the processing accuracy of the electric vehicle shock-absorbing bracket, improve the continuity of the curved surface connection, fully release stress, improve the tensile and anti-deformation performance of the bracket, reduce the topography error of the connecting curved surface between the surfaces of the bracket, and improve the consistency of the surface roughness of the bracket.

[0005] In the first aspect, the present invention provides a cutting method for an electric vehicle shock-absorbing bracket, including: Cutting the blank of the bracket processing base material to obtain a bracket base body adapted to the size of the shock-absorbing bracket, the bracket base body including a first mounting portion, a second mounting portion, and a shock-absorbing support portion connecting the first mounting portion and the second mounting portion; Performing tempering treatment on the bracket base body to remove stress from the first mounting portion, the second mounting portion, and the shock-absorbing support portion, and improve the anti-deformation performance of the first mounting portion, the second mounting portion, and the shock-absorbing support portion, so as to obtain an anti-deformation bracket base body; Clamp the anti-deformation bracket base by a fixture, and control the cutting head of the precision machining cutting machine to perform single-sided independent cutting on the anti-deformation bracket base, so as to form flat main surfaces on the first mounting portion, the second mounting portion, and the shock-absorbing support portion respectively. Then, according to the set tool path strategy, control the cutting head of the precision machining cutting machine to continuously move in three-dimensional space, and perform multi-sided synchronous cutting on the connecting parts between different main surfaces, so as to form a connecting curved surface at the connecting parts between different main surfaces.

[0006] In a second aspect, the present invention provides a shock-proof bracket for shock-proof of an electric vehicle, and the shock-proof bracket is processed and produced by using the cutting processing method of the above-mentioned shock-proof bracket for an electric vehicle.

[0007] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention provides a cutting processing method and a shock-proof bracket for an electric vehicle shock-proof bracket. By cutting the blank of the bracket processing base material, a bracket base adapted to the size of the shock-proof bracket is obtained. The bracket base includes a first mounting portion, a second mounting portion, and a shock-absorbing support portion connecting the first mounting portion and the second mounting portion. Temper the bracket base to remove stress from the first mounting portion, the second mounting portion, and the shock-absorbing support portion, and improve the anti-deformation performance of the first mounting portion, the second mounting portion, and the shock-absorbing support portion, so as to obtain an anti-deformation bracket base. Clamp the anti-deformation bracket base by a fixture, and control the cutting head of the precision machining cutting machine to perform single-sided independent cutting on the anti-deformation bracket base, so as to form flat main surfaces on the first mounting portion, the second mounting portion, and the shock-absorbing support portion respectively. Then, according to the set tool path strategy, control the cutting head of the precision machining cutting machine to continuously move in three-dimensional space, and perform multi-sided synchronous cutting on the connecting parts between different main surfaces, so as to form a connecting curved surface at the connecting parts between different main surfaces, thereby unifying the processing accuracy of the electric vehicle shock-proof bracket, improving the continuity of the curved surface connection, fully releasing stress, improving the tensile and anti-deformation performance of the bracket, reducing the profile error of the connecting curved surface between the bracket surfaces, and improving the consistency of the surface roughness of the bracket. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. Some specific embodiments of the present invention will be described in detail later with reference to the drawings in an exemplary rather than restrictive manner. The same reference numerals in the drawings denote the same or similar components or parts. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings: Figure 1It is a schematic flow chart of a cutting method for an anti-vibration bracket of an electric vehicle according to an embodiment of the present invention; Figure 2 It is a schematic structural diagram of an anti-vibration bracket of an electric vehicle according to an embodiment of the present invention, showing the first mounting portion, the second mounting portion, and the shock-absorbing support portion; Figure 3 It is a schematic structural diagram of an anti-vibration bracket of an electric vehicle according to an embodiment of the present invention, showing a partially flat main surface; Figure 4 It is a schematic structural diagram of an anti-vibration bracket of an electric vehicle according to an embodiment of the present invention, showing a partially connecting curved surface; Figure 5 It is a schematic structural diagram of an anti-vibration bracket of an electric vehicle according to an embodiment of the present invention, showing a bolt through-hole.

[0009] Explanation of reference numerals: 1. First mounting portion; 2. Second mounting portion; 3. Shock-absorbing support portion; 4. Flat main surface; 5. Connecting curved surface; 6. Bolt through-hole. Detailed implementation manners

[0010] In order to enable those skilled in the art of the present technology to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0011] Refer to Figures 1 - 5 , the embodiment of the present invention provides a cutting method for an anti-vibration bracket of an electric vehicle, including the following steps: S101. Cut the blank of the bracket processing substrate to obtain a bracket matrix adapted to the size of the anti-vibration bracket. The bracket matrix includes a first mounting portion 1, a second mounting portion 2, and a shock-absorbing support portion 3 connecting the first mounting portion and the second mounting portion; S102. Perform tempering treatment on the bracket matrix to remove stress from the first mounting portion, the second mounting portion, and the shock-absorbing support portion, and improve the anti-deformation performance of the first mounting portion, the second mounting portion, and the shock-absorbing support portion, so as to obtain an anti-deformation bracket matrix; S103. Clamp the anti-deformation bracket base body with a fixture, control the cutting head of the precision machining tool to perform single-sided independent cutting on the anti-deformation bracket base body, so as to form flat main surfaces 4 on the first mounting part, the second mounting part and the shock-absorbing support part respectively. Then, according to the set tool path strategy, control the cutting head of the precision machining tool to continuously move in three-dimensional space to perform multi-surface synchronous cutting on the connecting parts between different main surfaces, so as to form a connecting curved surface 5 at the connecting parts between different main surfaces.

[0012] It should be noted that in the traditional multi-fixture or multi-station cutting process, due to the incomplete consistency of the positioning reference each time, there are deviations in the relative positions between multiple key surfaces (the first mounting part, the second mounting part, the shock-absorbing support part) of the bracket, which affects the overall vehicle assembly accuracy and the consistency of the anti-seismic structure. Moreover, most of the existing processing methods only achieve simple transitions or chamfering when dealing with multi-surface connection areas, and cannot form a spatially continuous transition connecting curved surface, resulting in poor structural transition stiffness, obvious stress concentration, and easy fatigue damage. In addition, residual stress will be formed in the bracket processing base material (such as aluminum alloy base material) during rough machining and blanking, which may be released during machining to cause deformation, resulting in the accumulation of subsequent cutting errors and the final shape deviation. In this embodiment, by implementing a strategy combining single-sided independent cutting and multi-surface synchronous cutting on the basis of the anti-deformation bracket base body, it can be ensured that all key flat main surfaces are processed under the same clamping and positioning, greatly reducing the alignment error caused by multiple clamping, and keeping the surface accuracy of the whole bracket within a unified error range. The multi-surface synchronous cutting step enables the cutting tool head to continuously move in three-dimensional space according to the set tool path strategy, forming a smooth and continuous spatial transition curved surface at the connecting parts between different main surfaces, effectively improving the structural force consistency, prolonging the fatigue life, effectively reducing the surface fluctuation and roughness change, improving the overall surface quality, and meeting the high-performance requirements of the electric vehicle chassis system. Performing tempering treatment on the bracket base body before cutting can release the processing stress inside the material of the bracket processing base material caused by blanking cutting, etc., ensure the structural dimension stability during the subsequent cutting process, and improve the anti-deformation performance of the first mounting part, the second mounting part and the shock-absorbing support part.

[0013] Preferably, the set tool path strategy adopts a dynamic cutting feed speed control algorithm. Based on the data of tool load, spindle speed, and cutting temperature collected in real time, it dynamically adjusts the cutting feed speed and cutting depth to ensure that the connecting surface has uniform surface roughness and stable dimensional accuracy at different angles. It should be noted that during the multi-face synchronous cutting process, there are different spatial angles on the connecting surface (such as acute-angle connection, obtuse-angle transition, inclined angle, etc.). If the feed rate is fixed, the relative cutting state between the tool and the material will change significantly in different angle regions, which is likely to result in inconsistent surface roughness. Additionally, if the cutting process lacks dynamic response to factors such as spindle speed and cutting temperature, it is easy to cause local material plastic deformation, tool jumping, or minor deformation when the heat load increases or the cutting resistance suddenly changes, thereby leading to a decrease in the local dimensional accuracy of the connecting surface. In this embodiment, when the tool is machining a small-angle connection, due to an increase in load or spindle speed fluctuation, it can automatically reduce the cutting feed speed and cutting depth to avoid local material tearing or tool jumping caused by too fast feed or heat accumulation, and achieve consistent surface roughness in different angle regions. When it is detected that the tool load increases or the cutting temperature rises abnormally, the cutting parameters are dynamically adjusted to avoid the expansion of thermal deformation or rapid tool wear, enabling the machining process to adapt to the physical state changes in different machining regions and stabilizing the dimensional consistency of the final connecting surface.

[0014] Furthermore, in the dynamic cutting feed speed control algorithm, the cutting feed speed is calculated according to the curvature radius of the current tool position , the spindle speed and the tool diameter . The calculation formula for the cutting feed speed is: ; where is a material empirical constant, which is adjusted according to the characteristics of the surface cutting material and is used to compensate for the overheating problem during machining at small curvatures. It should be noted that during the machining of the multi-faceted spatial transition surface of the shock-proof bracket, when the tool passes through a region with a smaller radius of curvature (i.e., a region with a large curvature), the tool path bends more severely, the tool-material contact area per unit time increases, and the cutting heat is more concentrated, which easily causes accelerated tool wear, local overheating of the workpiece surface, and thermal deformation leading to the accumulation of machining errors, affecting dimensional accuracy and surface quality, etc. If a fixed cutting feed speed strategy is used, it is impossible to automatically adjust the cutting parameters according to the geometric curvature of the current tool position, which easily leads to too fast cutting in some regions with drastic curvature changes, resulting in negative thermal effects; while the cutting efficiency in the straight region is not high, causing a decrease in the overall machining efficiency. In this embodiment, when the tool enters a region with a small radius of curvature (such as an acute turn or a surface depression), the algorithm automatically reduces the cutting feed speed, making the cutting temperature rise curve smoother throughout the path, avoiding the adverse consequences of heat concentration, ultimately improving the surface quality, and reducing the contour error caused by thermal deformation. It enables the heat effect of the cutting speed to be constantly controlled throughout the entire path of the connecting surface region, improves the dimensional consistency, contour smoothness, and roughness uniformity of the multi-angle spatial surface transition zone, and realizes an intelligent adjustment of the machining process that takes into account both efficiency and quality.

[0015] Further, perform a non-linear dynamic correction on the cutting feed speed to obtain the corrected cutting feed speed , the corrected cutting feed speed satisfies the formula: ; where is the radius of curvature of the current tool position, is the spindle speed, is the tool diameter, is a material empirical constant, is the curvature change sensitive factor for adjusting the cutting response sensitivity according to the curvature gradient, is the unit arc length on the tool path under the curvature change rate.

[0016] It should be noted that in this embodiment, the formula satisfied by the corrected cutting feed speed contains the curvature change sensitive factor and the curvature change rate. When the tool passes through a transition region with drastic curvature changes, it automatically performs a secondary dynamic deceleration control on the feed speed to further reduce the heat load fluctuation and trajectory deviation at the path discontinuity points and steep change angles, so that the change in the surface roughness of the connecting surface during machining in the complex space segment can be controlled within a small range (within ±0.2 μm), and the contour accuracy can also be controlled within a small range (such as within ±0.01 mm), effectively improving the consistency and structural stability of the overall surface transition.

[0017] Preferably, the set tool path strategy adopts a path stacking algorithm based on screening of curvature extreme points to optimize the surface machining path of the connection part between different main surfaces. The distance between tool positions between layers in the path stacking algorithm satisfies the following algorithmic relationship: ; where is the second derivative of the cutting surface in the X direction, which is used to reflect the local curvature change rate.

[0018] It should be noted that when machining the surface of the connection area between multiple main surfaces of the shockproof bracket, if the distance between tool positions between layers set along the path direction (such as the X direction) is a fixed value, it is easy to have problems such as too large layer spacing in the high curvature mutation area (such as the sharp turning transition point), the tool cannot accurately depict the surface contour, resulting in undercut, stepped ripples or contour residuals; the layer overlap in the low curvature area is too dense, resulting in processing redundancy and low efficiency. In this embodiment, the second derivative of the cutting surface in the X direction is used to reflect the local curvature change rate, control the path density, automatically increase the tool position points at the places where the curvature changes violently, avoid shape distortion, and the processed connection surface is smoother and has stronger structural continuity; automatically sparse the path points in the flat area of the shape, avoid unnecessary repeated cutting, improve the operation efficiency of the numerical control machine tool and the path execution speed, save processing time and tool wear, and improve the processing cost performance.

[0019] Furthermore, the third derivative term of the cutting surface along the X direction is used as a local disturbance correction factor for the path density to dynamically adjust the distance between tool positions between layers, so as to enhance the response accuracy of the path density to the curvature mutation point, inflection point or fluctuating boundary area, and obtain the adjusted distance between tool positions between layers , and the adjusted distance between tool positions between layers satisfies the following algorithmic relationship: ; where is the third derivative of the machining surface in the X direction, which is used to reflect the speed change trend of the curvature change. is the disturbance response adjustment coefficient, and the value of the third derivative is set according to the material cutting characteristics and path sensitivity requirements. It should be noted that in this embodiment, the original path layer distance is corrected by the disturbance coefficient through the third derivative, and the tool position density between layers is further compressed in the area where the curvature change rate suddenly increases (such as the local steep change or corner transition section of the connection part), while maintaining the original spacing in the area where the curvature change rate slows down, so as to avoid the defects of response lag or insufficient path accuracy caused by simply relying on the second derivative, realize the early recognition of the surface mutation section and path pre-compensation, and effectively improve the shape continuity, step difference smoothness and actual surface accuracy of the connection surface machining.

[0020] Preferably, during the single-sided independent cutting process, the first mounting portion and the second mounting portion are respectively processed through cutting tool paths in different coordinate systems, and a positioning pin is applied to position the anti-deformation bracket base before processing, so that the flat main surfaces of the first mounting portion and the second mounting portion form a machining accuracy with a surface difference not exceeding 0.02 mm and the same height after cutting, thereby ensuring the assembly compatibility with the vehicle chassis structure. It should be noted that in multi-sided machining, especially for two mounting portions located on different structural surfaces (such as both ends or non-planar structures), if a unified coordinate system is used to control the machining path, it is easy to cause a small plane offset or angular error of the mounting surface in space due to coordinate system mismatch, insufficient tool angle compensation or asymmetric interference relationship. In addition, if the bracket base is not initially positioned stably and effectively (such as limited by a positioning pin) before fine machining, there will be a small amount of displacement or rotation of the base during multi-sided machining, which may cause surface difference accumulation in subsequent assembly and affect the connection accuracy between the bracket and the vehicle body. In this embodiment, by independently establishing machining coordinate systems (such as G54 and G55) for the two mounting portions, the machining of different plane angles, positions and tool feed paths can be optimized respectively, avoiding tool angle errors and path distortions caused by the limitation of a single coordinate system; at the same time, the positioning pin is used to limit the position before machining to ensure that the position of the bracket base in the fixture is unique and unchanged, eliminating the repeated positioning error caused by the residual freedom degree of the base, providing a reliable zero-point reference for precise machining under different coordinate systems subsequently, and making the flat main surfaces of the first mounting portion and the second mounting portion form a machining accuracy with a surface difference not exceeding 0.02 mm and the same height after cutting, thereby ensuring the assembly compatibility with the vehicle chassis structure.

[0021] Preferably, the control of the cutting tool path adopts a B-spline surface interpolation algorithm, so as to form a continuous G² curvature transition between multiple surfaces, avoiding abrupt changes in the edges at the joints or inconsistent chamfers. It should be noted that between the first mounting part, the second mounting part and the shock-absorbing support part of the shock-proof bracket, due to the obvious geometric angle changes in the transition area between surfaces, if the tool path adopts a linear interpolation or low-order interpolation algorithm (such as splicing of straight line segments or circular arc segments), it is easy to cause abrupt changes in the edges at the joints, the trajectory on the cutting path is not smooth, and the tool suddenly turns, resulting in over-cutting or under-cutting of the surface, forming a step difference in vision and structure, and it is impossible to uniformly control the smoothness of the chamfers between all connecting surfaces. In the intersection area connected in multiple directions, problems such as inconsistent chamfer sizes and abrupt curvature transitions will occur, affecting the assembly matching quality and causing stress concentration and a decrease in fatigue resistance. Moreover, if the interpolation method of the machining path is at the G0 (position continuous) or G1 (tangent continuous) level, although the processed surfaces are connected, the surfaces are not smooth, and it is difficult to meet the requirements of high-quality industrial surface machining. In this embodiment, the control of the cutting tool path adopts a machining path planning method of B-spline surface interpolation, which can accurately describe the geometric changes of complex surfaces and support high-order derivative continuity control. At the same time, compared with G0 (point continuous) and G1 (tangent continuous), the interpolation strategy at the G² level requires the first derivative (tangent) and the second derivative (curvature) at the surface joint to be continuous, thus achieving a double guarantee of stress continuity in structure and visual smoothness.

[0022] Preferably, the control of the cutting tool path adopts a NURBS-based contour interpolation algorithm, and the interpolation function is expressed as: ; where is the path parameter is the coordinate of the tool trajectory point at is the control vertex, is the B-spline basis function of order calculated based on the knot vector; is the non-negative weight coefficient of each control point, used to adjust the attraction of the control point to the path; the interpolation function is used to control the continuity and fitting accuracy of the tool trajectory in different curvature regions, so as to achieve G² continuous transition and local fitting adjustment of the path curve.

[0023] It should be noted that B-spline interpolation can achieve G² continuity, but it has limited control ability in areas with irregular curvature distributions (such as rapidly fluctuating surfaces and connection areas between different surfaces), and cannot perform local encryption or adjustment of the path according to the distance between control points or local shape details. If uniform B-spline interpolation is used, the influence of all control points is equal, and the path may deviate from the ideal contour in high-curvature areas, and it is impossible to enhance the adaptability of the path to key geometric shapes. The B-spline path is only controlled by fixed control points and the distribution of basis functions, lacking a mechanism to refine or weaken the influence of interpolation in a certain section through adjustable factors, resulting in a too rigid or too slow machining path. In this embodiment, a NURBS-based contour interpolation algorithm is used instead of the B-spline interpolation algorithm, and a weight coefficient is introduced into the interpolation function, making the influence of each control point on the final path adjustable, and it can better adapt to the trajectory shape control of irregular shapes or areas with local curvature anomalies. In the tool path fitting area, more control points can be arranged or the weight can be increased according to factors such as the strength of local curvature and the difficulty of transition; the path can approach the control points in the key area (fitting more closely), while maintaining a looser distribution in the flat area, realizing the intelligent allocation of machining resources. In this embodiment, by assigning a higher weight coefficient value to the high-curvature section, the tool path can better fit the target surface, effectively avoiding problems such as trajectory collapse or curvature deviation in the connection section. The adjustment of the weight coefficient

[0024] can make the path more smooth in the spatial transition zone between multiple surfaces, realizing local deformation compensation based on G² continuity, and ensuring consistent chamfer smoothness and natural topography transition.

[0024] Preferably, the tempering treatment adopts the T6 heat treatment standard, including holding at a constant temperature of 505°C for 2 hours and then rapidly water-cooling, and then tempering at 170°C for 12 hours to release the residual stress generated in the blanking and initial milling stages of the bracket base. It should be noted that in this embodiment, by adopting the T6 heat treatment standard, including holding at a constant temperature of 505°C for 2 hours and then rapidly water-cooling, and then tempering at 170°C for 12 hours to release the residual stress generated in the blanking and initial milling stages of the bracket base, thereby reducing the residual stress, improving the stability of the machining topography, enhancing the consistency of single-sided independent cutting and the flat main surface, and enhancing the path reference stability of the multi-surface connection curve.

[0025] Preferably, the residual stress prediction is carried out before the tempering treatment. The residual stress prediction adopts a finite element coupled stress field distribution model, and the corresponding deformation amount of the residual stress is calculated through a Poisson's ratio correction model , and the calculation formula is: ; where is the two-dimensional stress distribution in the unit area, is the elastic modulus of the material, is the Poisson's ratio of the material. It should be noted that although the T6 heat treatment can eliminate residual stress, in practice, the amount of residual stress accumulated in different parts of the material is uneven; if the tempering process parameters do not match the local stress distribution, it may lead to incomplete or excessive stress release, causing new deformations. The T6 heat treatment method cannot quantify the change of residual strain, making it difficult to optimize the heat treatment strategy. Moreover, it relies on empirical parameters (such as the holding time and tempering temperature) and cannot accurately predict the deformation trend of different regions through a mathematical model before heat treatment, resulting in possible micro-warpage of the structure after processing, affecting the assembly consistency. In this embodiment, by constructing a two-dimensional distribution model , high-precision modeling of the stress distribution of the entire bracket base during the blanking and initial cutting stages can be carried out, capturing the residual stress gradient in different curved surfaces, connection segments, and thin-walled regions, and calculating the corresponding deformation amount of the residual stress through the Poisson's ratio correction model When the two-dimensional distribution model combines the Poisson's ratio of the material , it reflects the longitudinal strain coupling phenomenon caused by transverse loads. The Poisson's ratio correction model is closer to the real material behavior and can be used for predicting local deformation trends, thus achieving accurate residual stress field modeling and quantification before heat treatment, realizing preheating compensation strategies and tempering uniformity control, enhancing the accuracy of deformation prediction, and improving the machining consistency of the connection surface.

[0026] Preferably, after the anti-deformation bracket base is obtained by tempering treatment, surface strain detection is carried out by a three-dimensional optical scanner, and the detection results of the surface strain detection are used to guide the tool path compensation calculation in the subsequent finishing stage to eliminate the micro-warpage error caused by the change of material structure while maintaining the original design morphology. It should be noted that although heat treatment can improve the material stability, it will inevitably cause micro-warpage and morphology deviation due to factors such as material structure rearrangement and internal stress release. As a high-precision and non-contact deformation measurement method, three-dimensional optical scanning has a measurement resolution from millimeters to micrometers, the ability to detect the contour of complex-shaped surfaces, and real-time digital modeling ability, which can achieve high-resolution deviation capture of the overall bracket and key functional surfaces (such as mounting surfaces and connecting curved surfaces), providing a quantitative basis for subsequent tool path correction, reducing the partial cutting caused by the slight bulging and shrinkage of the material after heat treatment, avoiding undercutting or residual layers caused by surface concavity, and improving the cutting consistency.

[0027] Preferably, the cutting head is a ball-end mill with a micro-edge inclination angle. The edge inclination angle of the ball-end mill is set within 10° to ensure micro-feed cutting when machining the curved surface area of the shock-absorbing support part, improve the finish of the surface transition area, and at the same time, continuously spray lubricating coolant to reduce tool wear and extend the tool service life. It should be noted that in this embodiment, a ball-end mill with a micro-edge inclination angle less than 10° can form progressive meshing cutting, with a delicate and stable feed rate, which is beneficial to controlling the contact area between the tool and the material and reducing the instantaneous cutting force. At the same time, the micro-edge inclination angle design can reduce the forward impact of the tool and avoid surface damage caused by sudden changes in cutting force. When transitioning between adjacent machining paths, micro-feed ensures that the material is cut layer by layer rather than torn, avoiding machining residues and improving the surface consistency and reflection uniformity of the curvature transition section, meeting the higher requirements for the smoothness of the connection. In addition, continuous lubricating and cooling spray controls the tool temperature rise, reduces micro-cracks or edge chipping caused by thermal expansion and contraction, improves cutting stability, and reduces phenomena such as frequent tool changes and surface roughness fluctuations caused by tool wear.

[0028] Preferably, during multi-face synchronous cutting, the finishing cutting machine tool is a five-axis linkage machining center. The five-axis linkage machining center simultaneously controls the linkage rotation of the XYZ spatial axes and the AB rotary axes through an industrial control system, so that the tool posture maintains the best contact angle with the complex spatial connection structure to complete the continuous connection surface forming between multiple included angle structures without repeated clamping. It should be noted that in this embodiment, by adopting the five-axis linkage machining center and the multi-axis collaborative control strategy of the industrial control system, continuous surface machining, single clamping forming, high-precision alignment, and high surface consistency output of multiple included angle connection areas on the electric vehicle shock-proof bracket can be achieved, improving the machinability and assembly accuracy of complex surface structures.

[0029] Preferably, the first installation part and the second installation part are provided with a through-hole machining process section during the cutting process. The through-hole machining process section is executed after the flat surface machining is completed. A high-speed drilling and milling integrated tool is used to complete the machining of the bolt through-hole 6, and the position and perpendicularity of the bolt through-hole are detected online by a special probe to ensure structural symmetry and assembly alignment accuracy. It should be noted that in the shock-proof bracket, the bolt through-hole is a mechanical connection interface and has strict assembly requirements for position and direction. If the hole position deviates or the perpendicularity error is too large, it will lead to uneven assembly stress, eccentric bolt load, reduced fatigue life, interference or jamming problems during the installation process, etc. In this embodiment, drilling and milling of the through-hole are carried out after the flat surface machining is completed, which can ensure that the hole machining reference comes from the precision-cut reference surface and improve the position consistency. At the same time, the high-speed drilling and milling tool can form in one step, reducing the secondary clamping error; and the online probe detection enables verification after each hole is machined, ensuring that each part meets the high positioning requirements.

[0030] Preferably, after the through-hole positions are machined, chamfering treatment is performed on the bolt through-holes, and a chamfer is provided at the mouth of each bolt through-hole to avoid stress concentration during bolt assembly. At the same time, burrs are removed by a sandblasting micro-treatment process in the chamfer edge area to improve the product assembly safety and the contact stress uniformity. It should be noted that the shockproof bracket belongs to a dual-structural member of load-bearing and vibration damping, and the through-holes need to withstand periodic fastening under dynamic loads. The chamfer can form a smooth transition area at the hole edge, reduce the stress gradient at the junction of the bolt and the hole wall, and improve the anti-fatigue life and connection reliability of the product. Removing burrs by a sandblasting micro-treatment process in the chamfer edge area can not damage the original geometric structure, achieve uniform surface roughening, and ensure assembly safety, the fitting integrity of the bolt and the through-hole, and the long-term structural stability.

[0031] Preferably, surface treatment is performed on the flat main surface. The surface treatment process includes anodic oxidation treatment and sealing treatment. The thickness of the anodic oxidation is controlled within 20 ± 2 μm, and the corrosion resistance is verified using the military standard neutral salt spray standard. The sealing treatment is used to further enhance the antioxidant and anti-pollution capabilities. It should be noted that the shockproof bracket of an electric vehicle is located in the chassis area and is exposed to a humid, waterlogged, and high-salt spray environment for a long time. In this embodiment, an anodic oxidation layer with a thickness of 20 ± 2 μm can effectively form a dense aluminum oxide protective film, enhance the anti-electrochemical corrosion ability of the substrate, and delay the damage processes such as local pitting corrosion, intergranular corrosion, or galvanic corrosion caused by corrosion. At the same time, considering that the oxide film after anodic oxidation itself contains micro-pore channels, if not sealed, it is easy to absorb moisture, adsorb pollutants or alkaline liquids, and is prone to local corrosion. In this embodiment, through the sealing treatment (such as nickel salt sealing) to block the pores, a stable and dense film layer is formed on the surface, which can inhibit the further diffusion of air, water vapor and ions, block the attachment paths of pollutants such as oil stains and dust, and enhance the overall anti-oxidation and anti-adhesion capabilities of the surface.

[0032] Preferably, after single-sided single-cutting is completed, a micro-deformation correction algorithm based on the Fourier frequency domain compensation model is used to correct the surface thermal deformation of the flat main surface. The compensation offset in the micro-deformation correction algorithm is: ; where is the amplitude of the th-order Fourier component, is the phase difference, is the workpiece length.

[0033] It should be noted that during the single-sided cutting process, especially on a relatively large flat surface (such as the installation reference surface), the heat of the cutting tool and the cutting force will cause local thermal expansion in the material, and the stress gradient will be released, resulting in minor warping, local bulging or depression. In this embodiment, the micro-deformation correction algorithm based on the Fourier frequency-domain compensation model is used to correct the surface thermal deformation of the flat main surface, and the height to be compensated can be calculated at the local position, improving the machining accuracy. The micro-deformation correction algorithm based on the Fourier frequency-domain compensation model can reflect periodic thermal wave deformation, asymmetric warping, multi-frequency superposition fluctuations, etc., improving the consistency and stability of surface repair and adapting to the machining error forms under multiple working conditions.

[0034] It should be pointed out that the above embodiments are only preferred specific embodiments of the present invention, and the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention. The protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A cutting method for an electric vehicle anti-vibration bracket, characterized in that: include: Cutting the bracket processing base material to obtain a bracket base body adapted to the size of the shockproof bracket, wherein the bracket base body includes a first mounting portion, a second mounting portion, and a shock-absorbing support portion connecting the first mounting portion and the second mounting portion; Tempering the bracket base to remove stress from the first mounting portion, the second mounting portion, and the shock-absorbing support portion, thereby improving the anti-deformation performance of the first mounting portion, the second mounting portion, and the shock-absorbing support portion, thereby obtaining a deformation-resistant bracket base; The anti-deformation bracket base is clamped by a fixture, and the cutting head of the finishing cutting machine is controlled to perform single-sided independent cutting on the anti-deformation bracket base to form flat main body surfaces on the first mounting part, the second mounting part and the shock-absorbing support part respectively. Then, according to the set tool path strategy, the cutting head of the finishing cutting machine is controlled to move continuously in three-dimensional space, and multi-sided synchronous cutting is performed on the connecting parts between different main body surfaces to form connecting curved surfaces at the connecting parts between different main body surfaces.

2. The cutting method of the anti-vibration bracket of the electric vehicle according to claim 1, characterized in that: The tool path setting strategy adopts a dynamic cutting feed rate control algorithm to dynamically adjust the cutting feed rate and cutting depth based on the tool load, spindle speed and cutting temperature data collected in real time.

3. The cutting method of the anti-vibration bracket of the electric vehicle according to claim 2, characterized in that: In the dynamic cutting feed speed control algorithm, the cutting feed speed According to the curvature radius of the tool's current position , spindle speed and tool diameter Calculated, the cutting feed rate The calculation formula is: ； in, It is an empirical constant, which is adjusted according to the characteristics of the surface cutting material and is used to compensate for overheating problems in areas with small curvature.

4. The cutting method of the anti-vibration bracket of an electric vehicle according to claim 1, characterized in that: The tool path strategy uses a path stacking algorithm based on curvature extreme point screening to optimize the surface machining path of the connection parts between different main body surfaces. The tool position layer distance in the path stacking algorithm is The following relationship is satisfied: ； in, It is the second-order derivative of the cutting surface in the X direction, which is used to reflect the rate of change of the local curvature.

5. The cutting method of the anti-vibration bracket of an electric vehicle according to claim 1, characterized in that: During the single-sided independent cutting process, the first mounting portion and the second mounting portion are respectively processed by cutting tool paths in different coordinate systems, and positioning pins are applied to the anti-deformation bracket base before processing, so that the flat main surfaces of the first mounting portion and the second mounting portion form a highly consistent surface difference after cutting with a processing accuracy of no more than 0.02mm, thereby ensuring assembly compatibility with the chassis structure of the entire vehicle.

6. The cutting method of the anti-vibration bracket of an electric vehicle according to claim 5, characterized in that: The cutting tool path is controlled by using a B-spline surface interpolation algorithm to form a continuous G² curvature transition between multiple surfaces to avoid sudden edge changes or inconsistent chamfers at the connection points.

7. The cutting method of the anti-vibration bracket of an electric vehicle according to claim 6, characterized in that: The control of the cutting tool path adopts the contour interpolation algorithm based on NURBS, and the interpolation function is expressed as: ； in, For path parameters The coordinates of the next tool path point, To control the vertices, The order of the node vector is calculated as B-spline basis functions; is the non-negative weight coefficient of each control point, which is used to adjust the attraction of the control point to the path; the interpolation function is used to control the continuity and fitting accuracy of the tool trajectory in different curvature areas to achieve G² continuous transition and local fitting adjustment of the path curve.

8. The cutting method of the anti-vibration bracket of an electric vehicle according to any one of claims 1 to 7, characterized in that: The tempering treatment adopts the T6 heat treatment standard, which includes constant temperature treatment at 505°C for 2 hours, rapid water cooling, and then tempering at 170°C for 12 hours to release the residual stress generated in the bracket base during the blanking and initial milling stages.

9. The cutting method of the anti-vibration bracket of an electric vehicle according to claim 8, characterized in that: The residual stress prediction is performed before tempering treatment. The residual stress prediction adopts the finite element coupled stress field distribution model and calculates the corresponding deformation of the residual stress through the Poisson's ratio correction model. , the calculation formula is: ； in, is the two-dimensional stress distribution in the unit area, is the elastic modulus of the material, is the Poisson's ratio of the material.

10. A shockproof bracket for electric vehicles, characterized in that: The anti-vibration bracket is processed and produced using the cutting processing method for the anti-vibration bracket of an electric vehicle as described in any one of claims 1 to 9.

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