Methods for improving the warping deformation of sunroof brackets

Abstract

The present application relates to the field of injection molding technology, and specifically to a method for improving the warping deformation of a sunroof bracket, comprising: establishing three-dimensional data of the sunroof bracket and preliminarily determining the matching surface and bonding requirements of the sunroof bracket; importing the product data into mold flow analysis software for simulation analysis, optimizing and analyzing the injection molding process parameters that affect the warping deformation of the sunroof bracket through an experimental design method with the goal of minimizing the warping deformation; calculating the warping deformation of the product, and if the warping deformation is less than or equal to a first evaluation threshold, performing a pre-deformation analysis on the product data; importing the three-dimensional solid data after the pre-deformation analysis into the mold flow analysis software again for simulation analysis, and comparing the simulation analysis results with theoretical data to obtain a deformation face difference value. If the deformation face difference value is less than or equal to a second evaluation threshold, the data is judged to be qualified. Thus, measures to improve the warping deformation of the sunroof bracket are proposed in advance before making the mold, saving manpower and mold repair costs.

Description

Technical Field

[0001] The present application relates to the field of injection molding technology, and in particular to a method for improving the warping deformation of a sunroof bracket. Background Art

[0002] With the continuous development of vehicles and the diversification of consumer demands, sunroofs have become a must-have feature for all models. Installed on the roof, sunroofs effectively circulate air inside the vehicle, increasing fresh air intake and providing a healthy and comfortable experience for the owner. They also provide a wider field of view and are often used for mobile photography and videography. Before installing a sunroof on a vehicle, a sunroof bracket must be installed at the roof opening. The hot-melt adhesive used to attach the sunroof bracket has extremely high bonding strength and uniform adhesion. However, due to deformation caused by injection molding and high temperature, the bracket can cause noticeable bulging and even debonding between the bracket and the roof, causing customer complaints.

[0003] At present, the injection deformation of the sunroof bracket is generally 5mm to 6mm, or even more than 8mm. The usual solution is to adjust the process, adjust the process parameters to the limit, and then use glue to force the sunroof bracket to be flat, and let the customer approve the deviation. This also greatly reduces the design of the sunroof, so that the actual produced vehicles cannot achieve the perfect design effect. Summary of the Invention

[0004] The purpose of this application is to provide a method for improving the warping and deformation of the sunroof bracket, which can propose measures to improve the warping and deformation of the sunroof bracket before making the mold, saving manpower and mold repair costs, and helping to improve customer satisfaction.

[0005] In order to achieve the above-mentioned purpose, the present application provides a method for improving the warping deformation of the sunroof bracket, including: establishing a three-dimensional data model of the sunroof bracket, and preliminarily determining the matching surface and bonding requirements of the sunroof bracket; importing the three-dimensional data model into the mold flow analysis software for simulation analysis, with the goal of minimizing the warping deformation, and optimizing the injection molding process parameters that affect the warping deformation of the sunroof bracket through the experimental design method; calculating the warping deformation of the product according to the injection molding process parameters of the optimized analysis, if the warping deformation is less than or equal to the first evaluation threshold, performing a pre-deformation analysis on the three-dimensional data model; importing the three-dimensional solid data after the pre-deformation analysis into the mold flow analysis software again for simulation analysis, and comparing the simulation analysis results with the theoretical data to obtain the deformation surface difference value, if the deformation surface difference value is less than or equal to the second evaluation threshold, the data is judged to be qualified.

[0006] Furthermore, a preliminary optimization analysis of the injection molding process parameters that affect the warping deformation of the sunroof bracket was conducted through the experimental design method, including: a full-factor experimental design analysis of the injection molding raw materials and gate position, and selecting the parameter combination with the smallest warping deformation as the preliminary optimization solution.

[0007] Furthermore, a preliminary optimization analysis of the injection molding process parameters that affect the warping deformation of the sunroof bracket is conducted through the experimental design method, which also includes: based on the preliminary optimization plan, a full-factor experimental design analysis of the filling time, holding pressure and holding time is conducted, and the parameter combination with the smallest warping deformation is selected as a further optimization plan.

[0008] Furthermore, if the warpage of the product calculated based on the injection molding process parameters obtained through optimization analysis is greater than a first evaluation threshold, the wall thickness or rib position of the product is corrected until the warpage is less than or equal to the first evaluation threshold.

[0009] Furthermore, a pre-deformation analysis of the three-dimensional data model includes: selecting a pre-deformation magnification coefficient, meshing the three-dimensional data model, and importing it into mold flow analysis software for simulation analysis, and comparing it with the warping deformation amount of theoretical data. If the difference between the maximum warping deformation amount corresponding to the pre-deformation data and the maximum warping deformation amount of the theoretical data is less than 10%, pre-deformation data is generated.

[0010] Furthermore, the production of pre-deformation data includes: for corners, making a line as the center line at the edge position where the warping deformation is 0, flipping it, dividing it into multiple steps for smoothing, and smoothing each step with a gradient thickness; for straight edges, flipping it at the maximum deformation point, dividing it into multiple steps for smoothing, and smoothing each step with a gradient thickness; generating inverse deformation three-dimensional solid data, and importing it into the mold flow analysis software again to re-simulate the warping deformation; comparing the new warping deformation result with the warping deformation of the theoretical data to obtain the deformation surface difference value; if the deformation surface difference value is less than or equal to the second evaluation threshold, the data is judged to be qualified.

[0011] Furthermore, if the deformation face difference value is greater than the second evaluation threshold, fine-tuning is performed on the local unqualified area until the deformation face difference value is less than or equal to the second evaluation threshold.

[0012] Furthermore, the method also includes: importing the three-dimensional data model into the finite element analysis software, setting the high-temperature working conditions for high-temperature simulation analysis, and comparing the simulation analysis results with the theoretical data to obtain the deformation surface difference value. If the deformation surface difference value is less than or equal to the second evaluation threshold, the data is judged to be qualified.

[0013] Furthermore, if the deformation face difference value is greater than a second evaluation threshold, the thickness of the bonding surface is adjusted for the local higher deformation area until the deformation face difference value is less than or equal to the second evaluation threshold.

[0014] Furthermore, the method also includes: determining the mold shrinkage rate and making the mold according to the qualified data.

[0015] The methods for improving the warping deformation of the sunroof bracket provided in each embodiment of the present application have the following beneficial effects: by analyzing the factors affecting the warping deformation of the sunroof bracket, the materials and gate positions that have the greatest impact on the deformation are first selected for optimization, and the optimization is controlled within a smaller range, which can effectively improve the accuracy and success rate of subsequent pre-deformation. The injection molding process is optimized through the DOE method to further reduce the amount of warping deformation. The product data after preliminary optimization is pre-deformed to determine the pre-deformation amplification coefficient, pre-deformation parameterization scheme and evaluation index, effectively solving the injection deformation problem of plastic parts. The product data is then imported into finite element analysis software to analyze the deformation under high-temperature working conditions. The mushroom buckle bonding structure is added to the location with large local deformation, which can effectively prevent the bulging problem caused by high-temperature deformation. Therefore, the embodiments of the present application propose measures to improve the warping deformation of the sunroof bracket before mold design, avoiding the warping deformation of the sunroof bracket and the bulging of the ceiling caused by injection molding or high temperature, reducing the failure rate, reducing customer complaints, increasing economic profits, enhancing brand image, and helping to improve customer satisfaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A flowchart showing a method for improving the warping deformation of a sunroof bracket provided by an embodiment of the present application is shown;

[0017] Figure 2 A top view of the skylight bracket provided in an embodiment of the present application in the XY plane is shown;

[0018] Figure 3 A schematic diagram of the pre-deformation structure of the skylight bracket provided in an embodiment of the present application is shown;

[0019] Figure 4 A top view of the skylight bracket provided in an embodiment of the present application in the XZ plane is shown. DETAILED DESCRIPTION

[0020] The following describes the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art will readily appreciate the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the various details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are intended only to illustrate the present invention and are not intended to limit the scope of protection of the present invention.

[0021] It should be noted that the illustrations provided in the following embodiments are merely schematic illustrations of the basic concept of the present invention. Therefore, the illustrations only show components related to the present invention and are not drawn according to the number, shape, and size of components in actual implementation. In actual implementation, the type, quantity, and proportion of each component may be changed arbitrarily, and the component layout may also be more complex.

[0022] like Figure 1 As shown, the embodiment of the present application provides a method for improving the warping deformation of the sunroof bracket, including the following steps S1 to S4. Figures 2-4 The specific steps of the method for improving the warping deformation of the sunroof bracket are described in detail.

[0023] Step S1: Create a three-dimensional data model of the skylight bracket and preliminarily determine the matching surface and bonding requirements of the skylight bracket. Figure 2 As shown, the three-dimensional data model of the skylight bracket can be established in three-dimensional data software, such as CATIA, ProE, Solidworks, etc., to preliminarily determine the matching surface and bonding requirements of the skylight bracket.

[0024] Step S2: Import the 3D data model into mold flow analysis software for simulation analysis. With the goal of minimizing the warpage deformation, the injection molding process parameters that affect the warpage deformation of the sunroof bracket are optimized and analyzed through the experimental design method.

[0025] Moldflow, a mold flow analysis software commonly used for mold flow analysis of injection molded parts, is used. The injection molding process parameters that influence the warpage y of a sunroof bracket include the raw material x1, filling time x2, holding pressure x3, holding time x4, part structure a, and gate location x5. The warpage y of a sunroof bracket is a function of these factors: raw material x1, filling time x2, holding pressure x3, holding time x4, part structure a, and gate location x5, expressed as y = k × F(x1, x2, x3, x4, x5, a). Raw material x1 and gate location x5 have the greatest impact, so optimization analysis can first determine raw material x1 and gate location x5, followed by filling time x2, holding pressure x3, and holding time x4.

[0026] Step S3: Calculate the warpage deformation of the product based on the injection molding process parameters obtained through optimization analysis. If the warpage deformation is less than or equal to a first evaluation threshold, perform a pre-deformation analysis on the optimized three-dimensional data model.

[0027] Based on the injection molding process parameters after optimization analysis, the warpage deformation is evaluated, where the first evaluation threshold can be 5mm. If the warpage deformation is ≤5mm, a pre-deformation analysis can be performed directly on the 3D data model.

[0028] Step S4: Import the three-dimensional solid data after the pre-deformation analysis into the mold flow analysis software again for simulation analysis, and compare the simulation analysis results with the theoretical data to obtain the deformation face difference value. If the deformation face difference value is less than or equal to the second evaluation threshold, the data is judged to be qualified.

[0029] If the 3D data model of the sunroof bracket does not require design changes after optimizing the injection molding process parameters, the theoretical data will serve as the initial 3D data for the sunroof bracket. The second evaluation threshold can be 0.5mm. If the deformation face difference is less than or equal to the second evaluation threshold, the data is considered qualified, confirming that the product's warpage deformation meets the design requirements.

[0030] According to the method for improving the warping deformation of the sunroof bracket provided in each embodiment of the present application, the warping of the sunroof bracket is simulated by using mold flow analysis software, with the goal of minimizing the warping deformation, and the injection molding process parameters that affect the warping deformation of the sunroof bracket are optimized and analyzed through the experimental design method to determine the optimized injection molding process parameters. Then, the pre-deformation accuracy is improved by parameterizing and process-based design of pre-deformation data and performing verification, so as to avoid the tedious problems such as large pre-deformation errors due to excessive deformation of parts, repeated mold trials, modification of processes and molds, and rectification due to unsuccessful pre-deformation. Therefore, measures to improve the warping deformation of the sunroof bracket are proposed before mold design, so as to avoid the warping deformation of the sunroof bracket and the bulging of the ceiling due to injection molding deformation, reduce the failure rate, reduce customer complaints, increase economic profits, enhance brand image, and help improve customer satisfaction.

[0031] The specific process of each step in the method for improving the warping deformation of the sunroof bracket is described in detail below.

[0032] Furthermore, in step S2, a preliminary optimization analysis of the injection molding process parameters that affect the warping deformation of the sunroof bracket is performed using an experimental design method, including:

[0033] Step S21: Perform a full factorial experimental design analysis on the injection molding raw materials and gate positions, and select the parameter combination with the smallest warpage deformation as the preliminary optimization solution.

[0034] The full-factorial Design of Experiment (DOE) analysis is to conduct the same number of simulation analyses on different level combinations of each key influencing factor. By performing DOE analysis on multiple parameters and multiple factors, it ensures that the optimization is qualified in one go, reduces the number of physical iterative verifications, shortens the development cycle, reduces development and verification costs, and effectively improves product development efficiency.

[0035] Specifically, this example first conducted a DOE analysis on the influencing factors, raw material x1 and gate location x5, with two levels set for each factor. The two levels for raw material x1 included polypropylene + glass fiber 30 (PP+GF30) and a terpolymer of acrylonitrile, butadiene, and styrene + glass fiber 30 (ABS+GF30); and the two levels for gate location x5 included open-fill and sequential valve fill. The DOE analysis was conducted with the goal of minimizing warpage. Based on the warpage results, the appropriate factor levels for x1 were determined to be ABS+GF30 and x5 to be open-fill. This result was then used to proceed to the next optimization analysis.

[0036] Furthermore, in step S2, preliminary optimization analysis of the injection molding process parameters that affect the warping deformation of the sunroof bracket by the experimental design method also includes:

[0037] Step S22: Based on the preliminary optimization scheme, a full factorial experimental design analysis is performed on the filling time, holding pressure, and holding time, and the parameter combination with the smallest warpage deformation is selected as a further optimization scheme.

[0038] Based on the analysis of raw material x1 and gate location x5, a DOE analysis was performed on fill time x2, holding pressure x3, and holding time x4, with two levels set for each factor. The two levels for fill time x2 were 2s and 3s, the two levels for holding pressure x3 were 30 MPa and 40 MPa, and the two levels for holding time x4 were 3s and 4s. The parameter combination that minimized warpage was selected as the solution for further optimization.

[0039] Specifically, DOE analysis was performed using Matlab software, and x2=2.5s, x3=35Mpa, and x4=3s were obtained. After the process parameters were determined, simulation analysis was performed in Moldflow, and the warpage deformation was obtained to be 7mm.

[0040] Furthermore, in step S2, if the warpage deformation of the product calculated based on the injection molding process parameters obtained through optimization analysis is greater than a first evaluation threshold, the wall thickness or rib position of the product is corrected until the warpage deformation is less than the first evaluation threshold.

[0041] As analyzed above, due to the large warpage deformation of 7mm, considering the product structure, the local wall thickness was thinned by 0.5mm, and the local ribs that have a large impact on the deformation were removed. Moldflow was used again to simulate the skylight bracket. The maximum warpage deformation result was 5mm, which is equal to the first evaluation threshold, and the optimization was more than 57%, controlling the large deformation within a smaller range.

[0042] It should be noted that if the three-dimensional data model of the sunroof bracket needs to be redesigned after optimizing and analyzing the injection molding process parameters, such as modifying the wall thickness or rib position, the theoretical data is the three-dimensional data of the sunroof bracket after the design is changed.

[0043] Furthermore, in step S3, performing pre-deformation analysis on the three-dimensional data model includes:

[0044] Select the pre-deformation magnification factor, divide the three-dimensional data model into a grid, and then import it into the mold flow analysis software for simulation analysis. The warpage deformation amount is compared with the theoretical data. If the difference between the maximum warpage deformation amount corresponding to the pre-deformation data and the maximum warpage deformation amount of the theoretical data is less than 10%, then the pre-deformation data is produced.

[0045] Specifically, pre-deformation is also called reverse deformation. First, the pre-deformation magnification coefficient α is set to 1, and the pre-deformation warping mesh export function of Moldflow is used to export it to stl format. Then, it is imported into Hypermesh mesh analysis software, and the mesh is divided and exported as a udm file. Then, it is imported into Moldflow for simulation. The maximum warping deformation is 5.7mm, which is compared with the theoretical data of 5mm. The difference percentage is 14%. The difference between the maximum warping deformation of the pre-deformation data and the maximum warping deformation of the theoretical data is >10%.

[0046] Reselecting the method coefficient α = 0.95 for simulation analysis, the warpage is 5.2mm, and the difference percentage is 4%, meeting the conditions and allowing the next step of pre-deformation data generation. If the difference between the maximum warpage corresponding to the pre-deformation data and the maximum warpage of the theoretical data is still greater than 10%, continue to reduce the pre-deformation magnification coefficient α by 0.05 and perform simulation analysis until the difference between the maximum warpage and the theoretical data is less than 10%.

[0047] Furthermore, in step S3, generating pre-deformation data includes:

[0048] Step S31: For the corner, draw a line as the center line at the edge where the warping deformation is 0, and perform flipping. Smoothing is divided into multiple steps, and each step is smoothed with a gradient thickness.

[0049] like Figure 3 As shown, at the corner, a line is drawn as the center line at the edge position AB where the warping deformation is 0, and the deformation of the maximum deformation point C is T1. Then the value of the flipped point C′ is αT1, and the smoothing is divided into N1 steps (when T1<3, N1=2, when T1>=3, N1=3), and each step is smoothed with a gradient of αT1 / N1 thickness.

[0050] In an example, a baseline is made with the warping deformation of A and B as 0 points, and the deformation of point C is T=5. Then the value of point C′ after flipping is T=5*0.8=4mm, N1=3, and the smoothing is divided into three steps, and each step is smoothed with 4 / 3=1.3mm; for point D, the deformation is T=3, then the value of point C′ after flipping is T=3*0.8=2.4mm, N2=2, and the smoothing is divided into 2 steps, and each step is smoothed with 2.4 / 2=1.2mm. The smoothing length is 50*2.4=120mm, and the width is 6*2.4=14.4mm.

[0051] Step S32: For the straight edge, the point of maximum deformation is flipped and smoothed into multiple steps, and each step is smoothed with thickness gradient;

[0052] For the straight edge, the deformation value of the maximum deformation point D is T2, so the value of the flipped point D′ is αT2, the smoothing length is 50*α*T2mm, and the width is 6*α*T2mm, which is divided into N2 steps (when T1<3, N2=2, when T1>=3, N2=3), and each step is smoothed with a gradient of αT2 / N2 thickness.

[0053] Step S33: Generate inverse deformed three-dimensional solid data, and import it into the mold flow analysis software for re-simulation.

[0054] Use software such as CATIA to smooth the matching surfaces again to generate three-dimensional solid data, export the three-dimensional solid data into the stp format, import the pre-deformed three-dimensional solid data into the Moldflow software again, and re-simulate the warpage deformation.

[0055] Step S34: Compare the new warping deformation result with the warping deformation of the theoretical data to obtain the deformation face difference value. If the deformation face difference value is less than or equal to the second evaluation threshold, the data is judged to be qualified.

[0056] Optionally, the second evaluation threshold is 0.5 mm. After re-simulation, the new simulation results are compared with the theoretical data to obtain the deformation face difference value. If the deformation face difference value is less than the second evaluation threshold, it is judged as qualified data.

[0057] Furthermore, in step S35, if the deformation face difference value is greater than the second evaluation threshold, fine-tuning is performed on the local unqualified area until the deformation face difference value is less than or equal to the second evaluation threshold.

[0058] Furthermore, the method for improving the warping deformation of the sunroof bracket also includes:

[0059] Step S5: Import the three-dimensional data model into the finite element analysis software, set the high-temperature working condition for high-temperature simulation analysis, and compare the simulation analysis results with the theoretical data to obtain the deformation surface difference value. If the deformation surface difference value is less than or equal to the second evaluation threshold, the data is judged to be qualified.

[0060] like Figure 4 As shown, the finite element analysis software can be ABAQUS. The 3D data of the skylight bracket is imported into ABAQUS. A high-temperature operating condition is set to 85°C for high-temperature simulation analysis. The simulation analysis results are compared with the theoretical data to obtain the deformation face difference value. If the deformation face difference value after simulation is less than or equal to the second evaluation threshold, the data is considered qualified.

[0061] Furthermore, in step S5, if the deformation face difference value is greater than the second evaluation threshold, the thickness of the bonding surface is adjusted for the local higher deformation area until the deformation face difference value is less than or equal to the second evaluation threshold.

[0062] If the deformation surface difference value is greater than the second evaluation threshold, the bonding surface thickness is adjusted for the local higher deformation area, for example, the position and number of mushroom buckle overlaps are adjusted until the deformation surface difference value is less than or equal to the second evaluation threshold.

[0063] Furthermore, the method for improving the warping deformation of the sunroof bracket also includes:

[0064] Step S6: Determine the mold shrinkage rate and make the mold according to the qualified data.

[0065] After considering the influence of injection deformation and / or high-temperature deformation, the mold is designed based on the adjusted optimization parameters. First, a trial mold is run on an existing mold using the optimized material, for example, ABS + GF30, to determine the actual material shrinkage, also known as mold shrinkage. The mold is then manufactured based on the qualified data from the simulation analysis and the actual measured material shrinkage.

[0066] The method for improving the warping deformation of the sunroof bracket provided in each embodiment of the present application includes product design, mold flow analysis, product correction, determination of pre-deformation amplification coefficient, production of pre-deformation data, high-temperature deformation analysis and mold design. The warping of the sunroof bracket is simulated by using mold flow analysis software to determine the material and flow channel design, and the injection molding process parameters are determined by DOE analysis. For products with large deformation, changes are made from the perspective of structural design to improve the success probability of pre-deformation, and the pre-deformation accuracy is improved by parameterizing and process-based design of pre-deformation data and performing verification. By combining product design, pre-deformation design and high-temperature deformation design, tedious problems such as repeated mold trials, modification of processes and molds, and rectification due to large pre-deformation errors caused by excessive deformation of parts and unsuccessful pre-deformation are avoided. Therefore, measures to improve the warping deformation of the sunroof bracket are proposed before mold design to avoid the warping deformation of the sunroof bracket and the bulging of the ceiling caused by injection molding or high temperature, reduce the failure rate, reduce customer complaints, increase economic profits, enhance brand image, and help improve customer satisfaction.

[0067] It should be noted that references in this specification to "one embodiment," "an embodiment," "an exemplary embodiment," "some embodiments," and the like indicate that the described embodiment may include a particular feature, structure, or characteristic, but not necessarily every embodiment includes that particular feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in conjunction with an embodiment, it is within the knowledge of those skilled in the art to implement such feature, structure, or characteristic in conjunction with other embodiments, whether explicitly described or not.

[0068] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for improving the warping deformation of a sunroof bracket, characterized in that: include: Establish a 3D data model of the skylight bracket and preliminarily determine the matching surface and bonding requirements of the skylight bracket; Importing the three-dimensional data model into mold flow analysis software for simulation analysis, optimizing and analyzing the injection molding process parameters that affect the warping deformation of the sunroof bracket through an experimental design method with the goal of minimizing the warping deformation; Calculating the warpage of the product based on the injection molding process parameters obtained through optimization analysis, and performing a pre-deformation analysis on the three-dimensional data model if the warpage is less than or equal to a first evaluation threshold; Importing the three-dimensional solid data after the pre-deformation analysis into the mold flow analysis software for simulation analysis again, and comparing the simulation analysis results with the theoretical data to obtain the deformation face difference value. If the deformation face difference value is less than or equal to the second evaluation threshold, the data is judged to be qualified; Performing pre-deformation analysis on the three-dimensional data model includes: Selecting a pre-deformation magnification factor, meshing the three-dimensional data model, and importing the model into mold flow analysis software for simulation analysis, and comparing the model with the warpage deformation of theoretical data; if the difference between the maximum warpage deformation corresponding to the pre-deformation data and the maximum warpage deformation of the theoretical data is less than 10%, then producing pre-deformation data; if the difference between the maximum warpage deformation corresponding to the pre-deformation data and the maximum warpage deformation of the theoretical data is greater than 10%, then reducing the pre-deformation magnification factor by an interval of 0.05 to perform pre-deformation analysis until the difference between the maximum warpage deformation corresponding to the pre-deformation data and the maximum warpage deformation of the theoretical data is less than 10%, then producing pre-deformation data; The producing of pre-deformation data comprises: For the corners, draw a line at the edge where the warping deformation is 0 as the center line for flipping, and the smoothing is divided into multiple steps. Each step is smoothed with a gradient thickness. For straight edges, the maximum deformation point is flipped, and the smoothing is divided into multiple steps. Each step is smoothed with a gradual thickness change. Generate anti-deformation 3D solid data and import it into mold flow analysis software to re-simulate the warpage deformation; Compare the new warping deformation result with the warping deformation of theoretical data to obtain the deformation surface difference value; If the deformation face difference value is less than or equal to the second evaluation threshold, the data is judged to be qualified.

2. The method according to claim 1, characterized in that The preliminary optimization analysis of the injection molding process parameters that affect the warping deformation of the sunroof bracket by the experimental design method includes: A full factorial experimental design analysis was conducted on the injection molding raw materials and gate positions, and the parameter combination with the smallest warpage deformation was selected as the preliminary optimization solution.

3. The method according to claim 2, characterized in that The preliminary optimization analysis of the injection molding process parameters that affect the warping deformation of the sunroof bracket by the experimental design method also includes: On the basis of the preliminary optimization scheme, a full factorial experimental design analysis was conducted on the filling time, holding pressure and holding time, and the parameter combination with the smallest warpage deformation was selected as the further optimization scheme.

4. The method according to claim 1, wherein If the warpage deformation of the product calculated based on the injection molding process parameters of the optimization analysis is greater than the first evaluation threshold, the wall thickness or rib position of the product is corrected until the warpage deformation is less than or equal to the first evaluation threshold.

5. The method according to claim 1, wherein If the deformation face difference value is greater than the second evaluation threshold, fine-tuning is performed on the local unqualified area until the deformation face difference value is less than or equal to the second evaluation threshold.

6. The method according to claim 1, wherein Also includes: The three-dimensional data model is imported into the finite element analysis software, a high-temperature working condition is set for high-temperature simulation analysis, and the simulation analysis results are compared with the theoretical data to obtain the deformation surface difference value. If the deformation surface difference value is less than or equal to the second evaluation threshold, the data is judged to be qualified.

7. The method according to claim 6, characterized in that If the deformation face difference value is greater than a second evaluation threshold, the thickness of the bonding surface is adjusted for the local higher deformation area until the deformation face difference value is less than or equal to the second evaluation threshold.

8. The method according to claim 1 or 7, characterized in that Also includes: Determine the mold shrinkage rate and make the mold according to the qualified data.

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