Welding Optimization Methods

Abstract

The present application discloses a welding optimization method, which belongs to the field of welding technology. The method includes: determining the sheet metal mid-surface model corresponding to each sheet metal model; determining multiple first welding points as target welding points in turn according to the preset welding order of multiple first welding points; combining the models to obtain a combined welding model; performing surface meshing and volume meshing on the model to obtain a model to be simulated; using the thickness of the sheet metal model, assigning a value to the thickness of the sheet metal mid-surface model corresponding to the sheet metal model; simulating the welding process of the assigned model to obtain a welding simulation process; simulating and analyzing the welding simulation process of multiple first welding points arranged in a preset welding order based on a simulation analysis algorithm to obtain a welding deformation; optimizing the welding simulation process of multiple first welding points based on the welding deformation. By adopting the present application, the deformation caused by the welding process can be evaluated to improve the control accuracy during the welding process.

Description

Technical Field

[0001] The present application relates to the field of welding technology, and in particular to a welding optimization method. Background Art

[0002] In the process of manufacturing the vehicle body, the control accuracy of the size and function of the vehicle body depends on the control accuracy of the vehicle body in the welding and other process. In the process of spot welding multiple stacked sheet metals, the fixture clamps the multiple sheet metals, and the welding gun heats the welding points of the multiple sheet metals, so that the steel at the first welding point of the sheet metals melts, and after cooling, the multiple sheet metals are joined together.

[0003] However, during the above welding process, the heating and cooling of the sheet metal, as well as the clamping force of the fixture on the sheet metal, will cause the sheet metal to deform to a certain extent, thereby affecting the control accuracy of the car body manufacturing.

[0004] Currently, there is a lack of a method to evaluate the deformation caused by welding and optimize the welding process. Summary of the invention

[0005] The embodiment of the present application provides a welding optimization method, which can solve the technical problems existing in the related art. The technical solution of the welding optimization method is as follows:

[0006] The present application provides a welding optimization method, the method comprising:

[0007] A welding optimization method, characterized in that the method comprises:

[0008] Acquire a model to be welded and a plurality of first welding points of each sheet metal model included in the model to be welded, wherein positions of the first welding points of the plurality of sheet metal models correspond to each other, and sections of the plurality of sheet metal models at the corresponding first welding point positions are parallel to and in contact with each other;

[0009] Determine a sheet metal mid-surface model corresponding to each sheet metal model and a second welding point included in each sheet metal mid-surface model, wherein a second welding point on each sheet metal mid-surface model corresponds to a first welding point on each sheet metal model;

[0010] Obtain two fixture models, two welding gun models and a weld core model corresponding to each first weld point;

[0011] According to a preset welding sequence of the plurality of first welding points, sequentially determining the plurality of first welding points as target welding points;

[0012] After the target weld point is determined each time, based on the relative position relationship between the weld core model and the first weld point, the relative position relationship between the weld core model and the two fixture models, and the relative position relationship between the weld core model and the two welding gun models, the multiple sheet metal mid-surface models, the weld core model corresponding to the target weld point, the two fixture models, and the two welding gun models are combined to obtain a combined welding model, in which two opposite side surfaces of the weld core model are respectively in contact with two adjacent sheet metal mid-surface models, the two fixture models are respectively located on both sides of the multiple sheet metal mid-surface models, and the two welding gun models are respectively located on both sides of the multiple sheet metal mid-surface models and are directly opposite to the weld core model;

[0013] Performing surface mesh division on multiple sheet metal mid-surface models in the combined welding model, the weld core model corresponding to the target weld point, the fixture model, and the welding gun model, and performing volume mesh division on the weld core model corresponding to the target weld point, the fixture model, and the welding gun model, to obtain a model to be simulated;

[0014] Using the thickness of the sheet metal model, assigning a value to the thickness of the sheet metal mid-surface model corresponding to the sheet metal model to obtain a model to be simulated after the assignment;

[0015] Performing welding process simulation on the model to be simulated after the assignment to obtain the welding simulation process corresponding to the target welding point;

[0016] Based on the simulation analysis algorithm, a simulation analysis is performed on the welding simulation process of a plurality of first welding points arranged in a preset welding sequence to obtain a welding deformation amount;

[0017] The welding simulation process of the plurality of first welding spots is optimized based on the welding deformation amount.

[0018] In a possible implementation, simulating the welding process on the assigned model to be simulated includes:

[0019] Based on a first preset force loading condition, force loading processing is performed on the fixture model at a first time point, wherein the direction of force loading in the first preset force loading condition is perpendicular to the direction of the sheet metal mid-surface model;

[0020] Based on a second preset force loading condition, force loading processing is performed on the welding gun model at a second time point, wherein the direction of force loading in the second preset force loading condition is perpendicular to the direction of the sheet metal mid-surface model, and the duration between the second time point and the first time point is the first preset duration;

[0021] Based on a preset heat loading condition, heat loading is performed on the weld nugget model corresponding to the target weld point at a third time point, wherein the duration between the third time point and the second time point is a second preset duration;

[0022] Establishing a binding contact relationship between the weld core model and the sheet metal mid-surface model at a fourth time point, wherein the time length between the fourth time point and the third time point is a third preset time length;

[0023] thermally unloading the weld core model corresponding to the target weld point at a fifth time point, wherein the duration between the fifth time point and the fourth time point is a fourth preset duration;

[0024] At a sixth time point, force unloading is performed on the welding gun model, wherein the time length between the sixth time point and the fifth time point is a fifth preset time length;

[0025] The fixture model is force unloaded at a seventh time point, wherein a time period between the seventh time point and the sixth time point is a sixth preset time period.

[0026] In a possible implementation, the performing force loading processing on the fixture model includes:

[0027] A force loading process is performed on a first preset node in the surface mesh corresponding to the fixture model.

[0028] In a possible implementation, the performing force loading processing on the welding gun model includes:

[0029] A force loading process is performed on a second preset node of the surface mesh corresponding to the welding gun model.

[0030] In a possible implementation, the step of performing heat loading on the weld nugget model corresponding to the target weld point includes:

[0031] A heat loading process is performed on the body mesh corresponding to the weld core model.

[0032] In a possible implementation, the optimizing the welding simulation process of the plurality of first welding points based on the welding deformation amount includes:

[0033] Based on the welding deformation amount and the preset deformation amount threshold, the welding simulation process of the plurality of first welding points is optimized.

[0034] In a possible implementation, the optimizing process of the welding simulation of the plurality of first welding points based on the welding deformation amount and the preset deformation amount threshold includes:

[0035] When the welding deformation amount is greater than or equal to the preset deformation amount threshold, the preset welding sequence is adjusted until the welding deformation amount is less than the preset deformation amount threshold.

[0036] In a possible implementation, the optimizing process of the welding simulation of the plurality of first welding points based on the welding deformation amount and the preset deformation amount threshold includes:

[0037] When the welding deformation amount is greater than or equal to the preset deformation amount threshold, the position of the first welding point is adjusted until the welding deformation amount is less than the preset deformation amount threshold.

[0038] In a possible implementation, the weld core model has a cylindrical structure, and an axial length of the cylindrical structure is equal to half of the sum of thicknesses of two adjacent sheet metal models corresponding to the weld core model.

[0039] In a possible implementation manner, both the fixture model and the welding gun model have a cylindrical structure.

[0040] The technical solution provided by the embodiments of the present application includes at least the following beneficial effects:

[0041] The embodiment of the present application provides a welding optimization method, in which a model to be welded and a plurality of first welding points of each sheet metal model included in the model to be welded are first obtained, and then a sheet metal mid-surface model corresponding to each sheet metal model and a second welding point included in each sheet metal mid-surface model are determined, and two fixture models, two welding gun models, and a welding core model corresponding to each first welding point are obtained. According to the preset welding sequence of the plurality of first welding points, the plurality of first welding points are determined as target welding points in sequence, and after each target welding point is determined, the plurality of sheet metal mid-surface models, the welding core models corresponding to the target welding points, the two fixture models, and the two welding gun models are combined to obtain a combined welding model. Then, the multiple sheet metal mid-surface models, weld core models, fixture models and welding gun models in the combined welding model are respectively meshed, and then the weld core model, fixture model and welding gun model in the combined model are meshed to obtain the model to be simulated, and the thickness of the sheet metal model is used to assign the thickness of the sheet metal mid-surface model corresponding to the sheet metal model to obtain the assigned model to be simulated, and the welding process is simulated on the assigned model to be simulated to obtain the welding simulation process corresponding to the target welding point. Based on the simulation analysis algorithm, the welding simulation process corresponding to the obtained multiple first welding points is simulated and analyzed to obtain the welding deformation. Then, based on the simulation analysis algorithm, the welding simulation process of the obtained multiple first welding points is simulated and analyzed to obtain the welding deformation, and then the welding method is optimized based on the welding deformation. With the present application, the deformation caused by the welding process can be evaluated based on the above-mentioned simulation process, and then the welding process is optimized based on the deformation, thereby improving the control accuracy in the welding process and improving the performance of the whole vehicle.

[0042] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0044] Figure 1 is a schematic diagram of a welding optimization method shown in an embodiment of the present application;

[0045] Figure 2 is a structural schematic diagram of a sheet metal mid-surface model and a first welding point shown in an embodiment of the present application;

[0046] Figure 3 It is a structural schematic diagram of a combined welding model shown in an embodiment of the present application;

[0047] Figure 4 is a structural schematic diagram of a model to be simulated shown in an embodiment of the present application;

[0048] Figure 5 It is a flow chart of a welding simulation process shown in an embodiment of the present application. DETAILED DESCRIPTION

[0049] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0050] The present application embodiment provides a welding optimization method, such as Figure 1 As shown, the method includes:

[0051] 101. Obtain a model to be welded and a plurality of first welding points of each sheet metal model included in the model to be welded.

[0052] The positions of the first welding points of the plurality of sheet metal models correspond to each other, and the cross-sections of the plurality of sheet metal models at the corresponding first welding point positions are parallel and in contact.

[0053] In the actual spot welding process, multiple sheet metals to be welded need to be stacked and placed, and the welding points of these multiple sheet metals need to be in contact. During welding, two clamps are used to clamp these multiple sheet metals together, and the clamping positions of the two clamps are located on both sides of the welding point. Then, two welding guns are used to heat both sides of the welding point of the stacked multi-layer sheet metals, so that the welding points of these multi-layer sheet metals are melted, thereby fusing the welding points of these multiple sheet metals together, and then leaving them to cool, thereby completing the welding process of one welding point.

[0054] Correspondingly, when performing the welding optimization method provided in the embodiment of the present application, it is necessary to first produce a model to be welded corresponding to the multi-layer sheet metal to be welded, and the model to be welded includes multiple sheet metal models, and the size of each sheet metal model can be the same as the size of the actual sheet metal. The number of sheet metal models included in the model to be welded can be any reasonable number, for example, it can be 2 or 4, etc., and the embodiment of the present application does not limit this. It is understandable that the structures of these multiple sheet metal models can be the same or different, and their structures need to be the same as the structure of the actual sheet metal.

[0055] The multiple sheet metal models all have multiple first welding points. The multiple sheet metal models are stacked and placed, and two adjacent sheet metal models are in contact at the positions of the multiple first welding points, that is, the cross-sections of the multiple sheet metal models at the positions of the corresponding first welding points are parallel and in contact with each other.

[0056] Among them, the first welding point on a sheet metal model can be a coordinate point on the surface where the sheet metal model contacts other sheet metal models. For example, among four stacked sheet metal models, the lower surface of the first layer of sheet metal model from top to bottom contacts the upper surface of the second layer of sheet metal model. Then, the first welding point of the first layer of sheet metal model is the coordinate point on the lower surface of the first layer of sheet metal model, and the first welding point of the second layer of sheet metal model can be a coordinate point on the upper surface of the second layer of sheet metal model, or a coordinate point on the lower surface.

[0057] Alternatively, the first welding point on a sheet metal model may also be a coordinate point located in the middle of the thickness of the sheet metal model. For example, if the coordinates of the welding point on the upper surface of the sheet metal model where spot welding is required are (100, 100, 100), and the coordinates of the welding point on the lower surface of the sheet metal model are (90, 100, 104), then the coordinates of the first welding point of the sheet metal model may be (95, 100, 102).

[0058] It can be understood that for the same welding point position, these multiple sheet metal models all have corresponding first welding points, and the positions of the first welding points of the multiple sheet metal models all correspond to each other. For example, in the case where there are three welding points in the actual welding process, each sheet metal model in the model to be welded also has three first welding points, and the three welding points of the sheet metal model correspond one by one to the positions of the three welding points of other sheet metal models.

[0059] 102. Determine a sheet metal mid-surface model corresponding to each sheet metal model and a second welding point included in each sheet metal mid-surface model.

[0060] Wherein, a second welding point on each sheet metal mid-surface model corresponds to a first welding point on each sheet metal model.

[0061] In implementation, based on the thickness of each sheet metal model in the model to be welded, the sheet metal mid-surface model of each sheet metal model is determined, and the sheet metal mid-surface model corresponding to the sheet metal model is the surface located between the upper surface and the lower surface of the sheet metal model.

[0062] After determining the sheet metal mid-surface model corresponding to each sheet metal model, the second welding point in the sheet metal mid-surface model corresponding to the first welding point in the sheet metal model can be determined based on the correspondence between each coordinate point included in the sheet metal mid-surface model and the coordinate points on the upper surface and the lower surface of the sheet metal model, such as Figure 2 As shown, the corresponding relationship between each first spot weld and the second spot weld can then be stored.

[0063] 103. Obtain two fixture models, two welding gun models, and a weld core model corresponding to each first weld point.

[0064] During implementation, workers can build fixture models, welding gun models and weld core models based on actual welding conditions.

[0065] When welding optimization is required, obtain pre-built fixture models, welding gun models, and weld nugget models.

[0066] Among them, the fixture model can be a model with the same structure and size as the actual fixture, or it can be a simplified model of the actual fixture. In order to reduce the amount of calculation, the clamping part of the fixture head can be simplified as a fixture model. In an embodiment of the present application, the fixture model can have a cylindrical structure, and the area of ​​the cross-section of the cylindrical structure perpendicular to the axis can be equal to the contact area between the actual clamping part of the fixture head and the sheet metal. In this way, the subsequent simulation analysis can be closer to reality, thereby improving the accuracy of the welding deformation obtained through simulation analysis.

[0067] Similarly, the welding gun model can be a model with the same structure and size as the actual welding gun structure, or it can be a simplified model of the actual welding gun. In the embodiment of the present application, the welding gun model can have a cylindrical structure, and the area of ​​the cross-section of the cylindrical structure perpendicular to the axis can be equal to the contact area between the head of the actual welding gun and the sheet metal. Since the welding gun will also exert a certain pressure on the sheet metal during the actual welding process, such a setting can also make the subsequent simulation analysis closer to reality, thereby improving the accuracy of the welding deformation.

[0068] For the weld core model, in order to make it correspond to the welding gun model, it can also have a cylindrical structure, and the diameter of the weld core model can be equal to the diameter of the welding gun model. As for the axial length of the weld core model, there can be multiple settings, two of which are listed below:

[0069] First, the axial length of the weld core model (ie, the axial length of the cylindrical structure) is equal to half of the sum of the thicknesses of two adjacent sheet metal models corresponding to the weld core model.

[0070] In this case, when the number of sheet metal mid-surface models is 2, the number of weld core models is 1, and when the number of sheet metal mid-surface models is greater than 2, the number of weld core models is one less than the number of sheet metal mid-surface models, and each weld core model is located between two adjacent sheet metal mid-surface models, and its axial length is equal to half of the sum of the thicknesses of the sheet metal models corresponding to the two adjacent sheet metal mid-surface models. It can be understood that the thickness of the sheet metal model here refers to the thickness at the location of the first weld point.

[0071] Second, the axial length of the weld core model is equal to the difference between the thickness of the multiple sheet metal models at the location of the first weld point and half of the thickness of the two sheet metal models located on both sides of the stacked structure. Regardless of the number of sheet metal mid-surfaces, the weld core model is located between the two sheet metal mid-surface models on both sides of the stacked structure.

[0072] 104. According to a preset welding sequence of the plurality of first welding points, determine the plurality of first welding points as target welding points in sequence.

[0073] During implementation, the staff may first set the welding sequence of the multiple first welding points based on experience, that is, obtain a preset welding sequence.

[0074] In implementation, multiple first welding points are determined as target welding points in sequence according to a preset welding sequence. After each target welding point is determined, steps 105-108 are performed to obtain a welding simulation process corresponding to the target welding point, thereby obtaining a welding model process corresponding to the multiple first welding points. For example, each sheet metal model has four first welding points. Based on the preset welding sequence, the first welding point A is determined as the target welding point in step 104, and then the first welding point A is processed by steps 105-108 to obtain the welding simulation process corresponding to the first welding point A. Then, according to the preset welding sequence, the first welding point B is determined as the target welding point, and then the first welding point B is processed by steps 105-108 to obtain the welding simulation process corresponding to the first welding point B. Then, according to the preset welding sequence, the first welding point C is determined as the target welding point, and then the first welding point C is processed by steps 105-108 to obtain the welding simulation process corresponding to the first welding point C. Finally, according to the preset welding sequence, the first welding point D is determined as the target welding point, and then the first welding point D is processed by steps 105-108 to obtain the welding simulation process corresponding to the first welding point D. In the above manner, the welding simulation processes corresponding to the four first welding points are obtained.

[0075] 105. After the target weld point is determined each time, based on the relative position relationship between the weld core model and the first weld point, the relative position relationship between the weld core model and the two fixture models, and the relative position relationship between the weld core model and the two welding gun models, multiple sheet metal mid-surface models, the weld core models corresponding to the target weld point, the two fixture models, and the two welding gun models are combined to obtain a combined welding model.

[0076] In implementation, the weld core model can be combined with multiple sheet metal mid-surface models based on the relative position relationship between the weld core model and the first weld point, and the relative position relationship between the first weld point and the second weld point. Then, based on the relative position relationship between the weld core model and the two fixture models, and the relative position relationship between the weld core model and the two welding gun models, the two fixture models, the two welding gun models, the combined weld core model, and the multiple sheet metal mid-surface models are combined to obtain a combined welding model.

[0077] It can be understood that, according to the preset welding sequence, after the first first weld point is determined as the target weld point, when determining the combined welding model, the sheet metal mid-surface model described in the above operation refers to the sheet metal mid-surface model determined in step 102, and when the subsequent other first weld points are respectively determined as target weld points, when determining the combined welding model, the sheet metal mid-surface model described above refers to the sheet metal mid-surface model after the welding process of the target weld point before the current target weld point is simulated.

[0078] Below, the structure in the combined welding model is introduced by taking the first weld core model as an example:

[0079] like Figure 3 As shown ( Figure 3 The fixture model and welding gun model shown in the figure are cross-sections of a cylindrical structure along the axial direction). In the combined welding model, two opposite side faces (or end faces) of the weld core model are in contact with two adjacent sheet metal mid-surface models respectively. The two fixture models are respectively located on both sides of the multiple sheet metal mid-surface models. The two welding gun models are respectively located on both sides of the multiple sheet metal mid-surface models and are directly opposite to the weld core model.

[0080] Furthermore, the axes of the cylindrical structures of the two fixture models are collinear, and the axes of the cylindrical structures of the fixture models are perpendicular to the cross-section at the corresponding position of the sheet metal mid-surface model, and the distance between the end face of the fixture model close to the sheet metal mid-surface model and the sheet metal mid-surface model on the side is half the thickness of the sheet metal model corresponding to the sheet metal mid-surface model on the side, wherein the sheet metal mid-surface model on the side refers to two sheet metal mid-surface models located on both sides of a plurality of stacked sheet metal mid-surface models.

[0081] Similarly, the axes of the cylindrical structures of the two welding guns are collinear, and the axis of the cylindrical structure of the welding gun model is perpendicular to the section at the corresponding position of the sheet metal mid-surface model, and the distance between the end face of the welding gun model close to the sheet metal mid-surface model and the sheet metal mid-surface model on the side is half the thickness of the sheet metal model corresponding to the sheet metal mid-surface model on the side.

[0082] 106. Perform surface meshing on multiple sheet metal mid-surface models in the combined welding model, weld core models corresponding to target weld points, fixture models and welding gun models, and perform volume meshing on weld core models, fixture models and welding gun models corresponding to target weld points to obtain the model to be simulated.

[0083] In implementation, after the combined welding model is obtained, surface meshing can be performed on multiple sheet metal mid-surface models, weld core models corresponding to target weld points, fixture models, and welding gun models in the combined welding model.

[0084] The shapes of the surface meshes of these models may be any reasonable shapes, for example, triangles, quadrilaterals, etc., and the shapes of the surface meshes of these models may be the same or different, which is not limited in the embodiments of the present application.

[0085] The size of the surface mesh of the above-mentioned model may also be any reasonable size, for example, 1-2 mm, etc., and the sizes of the surface meshes of these models may be equal or unequal, which is not limited in the embodiment of the present application.

[0086] After the surface mesh is established, the weld core model corresponding to the target weld point can be meshed into a volume based on multiple surface meshes, the fixture model can be meshed into a volume based on multiple surface meshes, and the welding gun model can be meshed into a volume based on multiple surface meshes, so as to obtain the model to be simulated, such as Figure 4 shown.

[0087] 107. Use the thickness of the sheet metal model to assign a value to the thickness of the sheet metal mid-surface model corresponding to the sheet metal model to obtain the assigned model to be simulated.

[0088] In implementation, the thickness of the sheet metal mid-surface model corresponding to the sheet metal model can also be assigned based on the thickness of each sheet metal model. In this way, in subsequent simulation analysis, simulation analysis can be performed based on the surface mesh of the sheet metal mid-surface model, without the need to perform simulation analysis based on multiple body meshes of the sheet metal model, which greatly reduces the amount of calculation and improves simulation efficiency.

[0089] 108. Perform welding process simulation on the model to be simulated after the assignment, and obtain the welding simulation process corresponding to the target welding point.

[0090] In implementation, the welding process of the model to be simulated after the assignment can be simulated based on the actual welding situation, so as to obtain the welding model process corresponding to the target welding point.

[0091] Through the above steps 105-108, the welding simulation process corresponding to the multiple first welding points can be obtained.

[0092] 109. Based on the simulation analysis algorithm, a simulation analysis is performed on the welding simulation process of multiple first welding points arranged in a preset welding sequence to obtain the welding deformation.

[0093] The simulation analysis algorithm may be any reasonable algorithm, for example, a CAE (Computer Aided Engineering) algorithm, etc., which is not limited in the embodiments of the present application.

[0094] 110. Optimize the welding simulation process of the plurality of first welding points based on the welding deformation amount.

[0095] During implementation, the staff can make an evaluation based on the obtained welding deformation. When the welding deformation is too large, the welding simulation process of the above-mentioned multiple first welds can be optimized, and then steps 101-109 can be performed again to determine the optimized welding deformation, thereby achieving the purpose of improving the control accuracy during the welding process.

[0096] In one possible implementation, Figure 5 As shown, the welding simulation process of the target weld point can be as follows:

[0097] 501. Based on a first preset force loading condition, perform force loading processing on a fixture model at a first time point.

[0098] Among them, the direction of force loading in the first preset force loading condition is a direction perpendicular to the mid-surface model of the sheet metal.

[0099] This step is used to simulate the clamping force of the fixture on multiple sheet metals during the actual welding process. The first preset force loading condition includes the magnitude and direction of the clamping force, the magnitude of which can be determined based on the magnitude of the clamping force of the fixture on the sheet metal during the actual welding process, and the direction is perpendicular to the mid-surface model of the sheet metal.

[0100] In one possible implementation, when force loading is performed on the fixture model, force loading can be performed on the first preset node in the surface mesh corresponding to the fixture model, wherein the first preset node of the surface mesh can be a preset vertex in the surface mesh, or the center point of the surface mesh, etc., which is not limited to this embodiment of the present application.

[0101] In implementation, force loading processing may be performed on the first preset nodes in the plurality of surface meshes on the end surface of the fixture model close to the sheet metal mid-surface model, that is, the clamping force and direction at each first preset node may be assigned.

[0102] 502. Based on a second preset force loading condition, perform force loading processing on the welding gun model at a second time point.

[0103] Among them, the direction of force loading in the second preset force loading condition is perpendicular to the direction of the sheet metal mid-surface model, and the time length between the second time point and the first time point is the first preset time length.

[0104] This step is used to simulate the force exerted by the welding gun on multiple sheet metals when the welding gun is placed at the position of the first welding point of the sheet metal during the actual welding process, wherein the first preset duration can be preset based on the duration between the two steps of setting the fixture position to setting the welding gun position during the actual welding process.

[0105] The second preset force loading condition includes the magnitude and direction of the force applied by the welding gun. The magnitude can be determined based on the magnitude of the force applied by the welding gun to the sheet metal during the actual welding process, and the direction is perpendicular to the direction of the mid-surface model of the sheet metal.

[0106] In one possible implementation, when the welding gun model is force loaded, the force loading process can be performed on the second preset node in the surface mesh corresponding to the welding gun model, wherein the second preset node of the surface mesh can be a preset vertex in the surface mesh, or the center point of the surface mesh, etc., which is not limited in this embodiment of the present application.

[0107] In implementation, force loading processing may be performed on a plurality of second preset nodes in the surface meshes on the end surface of the welding gun model close to the sheet metal mid-surface model, that is, the force and direction at each second preset node may be assigned a value.

[0108] 503. Based on a preset heat loading condition, perform heat loading processing on the weld core model corresponding to the target weld point at a third time point.

[0109] The duration between the third time point and the second time point is the second preset duration.

[0110] This step is used to simulate the situation of the sheet metal when the welding gun heats the first welding point of the sheet metal during the actual welding process, wherein the second preset time length can be preset based on the time length between the two steps of setting the welding gun position and controlling the welding gun to start heating during the actual welding process.

[0111] The preset heat loading condition includes the temperature of the weld nugget, which can be determined based on the temperature of the sheet metal or the temperature of the welding gun when the welding gun heats the sheet metal during the actual welding process.

[0112] In a possible implementation, when the weld core model is thermally loaded, the body mesh corresponding to the weld core model may be thermally loaded.

[0113] In implementation, if there are multiple weld core models at the target weld point, all of the multiple weld core models need to be subjected to heat loading treatment.

[0114] 504. At the fourth time point, a binding contact relationship is established between the weld core model and the sheet metal mid-surface model.

[0115] The duration between the fourth time point and the third time point is the third preset duration.

[0116] This step is used to simulate the situation in which multiple sheet metals are fused at the target welding point during the actual welding process, wherein the third preset duration can be preset based on the duration between the two steps of controlling the welding gun to start heating and the fusion of multiple sheet metals at the target welding point during the actual welding process.

[0117] 505. At a fifth time point, thermally unload the weld core model corresponding to the target weld point.

[0118] Among them, the duration between the fifth time point and the fourth time point is the fourth preset duration.

[0119] This step is used to simulate the situation when the welding gun is controlled to stop heating after multiple sheet metals are fused at the target welding point during the actual welding process, wherein the fourth preset time length can be preset based on the time length between the two steps of fusing multiple sheet metals at the target welding point to controlling the welding gun to stop heating during the actual welding process.

[0120] 506. At a sixth time point, force unloading is performed on the welding gun model.

[0121] Among them, the duration between the sixth time point and the fifth time point is the fifth preset duration.

[0122] This step is used to simulate the situation when the welding gun is removed from the sheet metal during the actual welding process (i.e., the situation when the welding gun no longer applies force to the sheet metal), wherein the fifth preset time length can be preset based on the time length between controlling the welding gun to stop heating and removing the welding gun.

[0123] 507. At the seventh time point, the fixture model is unloaded.

[0124] Among them, the duration between the seventh time point and the sixth time point is the sixth preset duration.

[0125] This step is used to simulate the situation when the clamp is removed from the sheet metal during the actual welding process (i.e., the situation when the clamp no longer applies clamping force to the sheet metal), wherein the sixth preset time length can be preset based on the time length between the two steps of removing the welding gun and removing the clamp.

[0126] In one possible implementation, the above setting is based on a simulation of a situation in which the position of the fixture corresponding to each first weld point is not the same during the actual welding process. If the position of the fixture remains unchanged when welding multiple first weld points, then when simulating welding for the first first weld point, only steps 501-506 need to be performed, and when simulating welding for the last first weld point, only steps 502-507 need to be performed. For other first weld points located between the first first weld point and the last first weld point, only steps 502-506 need to be performed.

[0127] In a possible implementation, the method for optimizing the welding simulation process of the plurality of first welds based on the welding deformation amount may be: optimizing the welding simulation process of the plurality of first welds based on the welding deformation amount and a preset deformation amount threshold.

[0128] During implementation, the staff can set preset deformation thresholds for the welding deformation of the multiple sheet metals based on actual needs.

[0129] When the welding deformation obtained by the simulation analysis is greater than or equal to the preset deformation threshold, it means that the simulated welding process will cause serious deformation of these multiple sheet metals. At this time, it is necessary to optimize the welding simulation process of the multiple first welding points to reduce the welding deformation, thereby improving the control accuracy in the welding process and further improving the performance of the entire vehicle.

[0130] When the welding deformation obtained by the simulation analysis is less than the preset deformation threshold, it means that the welding simulation process of the multiple first welding points causes less deformation to the sheet metal. Therefore, the actual sheet metal can be welded according to the welding simulation process of the multiple first welding points.

[0131] There are many ways to optimize the welding model process. The following two methods are introduced as examples:

[0132] The first one is that when the welding deformation amount is greater than or equal to the preset deformation amount threshold, the preset welding sequence is adjusted until the welding deformation amount is less than the preset deformation amount threshold.

[0133] In implementation, multiple preset welding sequences can be set, and simulation analysis can be performed on each of these preset welding sequences to obtain welding deformation amounts corresponding to different welding sequences. A preset welding sequence with the smallest welding deformation amount can be selected to weld actual sheet metal.

[0134] The second method is to adjust the position of the first welding point when the welding deformation amount is greater than or equal to the preset deformation amount threshold value until the welding deformation amount is less than the preset deformation amount threshold value.

[0135] During implementation, when the welding deformation is too large, the positions of all or part of the first welds on the sheet metal can be adjusted based on the actual situation on the sheet metal, and simulation can be performed again until the position of the first weld is determined when the welding deformation is less than the preset deformation threshold, and then the actual sheet metal is welded according to the position of the first weld.

[0136] The technical solution provided by the embodiments of the present application includes at least the following beneficial effects:

[0137] The embodiment of the present application provides a welding optimization method, in which a model to be welded and a plurality of first welding points of each sheet metal model included in the model to be welded are first obtained, and then a sheet metal mid-surface model corresponding to each sheet metal model and a second welding point included in each sheet metal mid-surface model are determined, and two fixture models, two welding gun models, and a welding core model corresponding to each first welding point are obtained. According to the preset welding sequence of the plurality of first welding points, the plurality of first welding points are determined as target welding points in sequence, and after each target welding point is determined, the plurality of sheet metal mid-surface models, the welding core models corresponding to the target welding points, the two fixture models, and the two welding gun models are combined to obtain a combined welding model. Then, the multiple sheet metal mid-surface models, weld core models, fixture models and welding gun models in the combined welding model are respectively meshed, and then the weld core model, fixture model and welding gun model in the combined model are meshed to obtain the model to be simulated, and the thickness of the sheet metal model is used to assign the thickness of the sheet metal mid-surface model corresponding to the sheet metal model to obtain the assigned model to be simulated, and the welding process is simulated on the assigned model to be simulated to obtain the welding simulation process corresponding to the target welding point. Based on the simulation analysis algorithm, the welding simulation process corresponding to the obtained multiple first welding points is simulated and analyzed to obtain the welding deformation. Then, based on the simulation analysis algorithm, the welding simulation process of the obtained multiple first welding points is simulated and analyzed to obtain the welding deformation, and then the welding method is optimized based on the welding deformation. With the present application, the deformation caused by the welding process can be evaluated based on the above-mentioned simulation process, and then the welding process is optimized based on the deformation, thereby improving the control accuracy in the welding process and improving the performance of the whole vehicle.

[0138] The above description is only an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A welding optimization method, characterized in that: The method comprises: Acquire a model to be welded and a plurality of first welding points of each sheet metal model included in the model to be welded, wherein positions of the first welding points of the plurality of sheet metal models correspond to each other, and sections of the plurality of sheet metal models at the corresponding first welding point positions are parallel to and in contact with each other; Determine a sheet metal mid-surface model corresponding to each sheet metal model and a second welding point included in each sheet metal mid-surface model, wherein a second welding point on each sheet metal mid-surface model corresponds to a first welding point on each sheet metal model; Obtain two fixture models, two welding gun models and a weld core model corresponding to each first weld point; According to a preset welding sequence of the plurality of first welding points, sequentially determining the plurality of first welding points as target welding points; After the target weld point is determined each time, based on the relative position relationship between the weld core model and the first weld point, the relative position relationship between the weld core model and the two fixture models, and the relative position relationship between the weld core model and the two welding gun models, the multiple sheet metal mid-surface models, the weld core model corresponding to the target weld point, the two fixture models, and the two welding gun models are combined to obtain a combined welding model, in which two opposite side surfaces of the weld core model are respectively in contact with two adjacent sheet metal mid-surface models, the two fixture models are respectively located on both sides of the multiple sheet metal mid-surface models, and the two welding gun models are respectively located on both sides of the multiple sheet metal mid-surface models and are directly opposite to the weld core model; Performing surface mesh division on multiple sheet metal mid-surface models in the combined welding model, the weld core model corresponding to the target weld point, the fixture model, and the welding gun model, and performing volume mesh division on the weld core model corresponding to the target weld point, the fixture model, and the welding gun model, to obtain a model to be simulated; Using the thickness of the sheet metal model, assigning a value to the thickness of the sheet metal mid-surface model corresponding to the sheet metal model to obtain a model to be simulated after the assignment; Performing welding process simulation on the model to be simulated after the assignment to obtain the welding simulation process corresponding to the target welding point; Based on the simulation analysis algorithm, a simulation analysis is performed on the welding simulation process of a plurality of first welding points arranged in a preset welding sequence to obtain a welding deformation amount; The welding simulation process of the plurality of first welding spots is optimized based on the welding deformation amount.

2. The welding optimization method according to claim 1, characterized in that: The step of simulating the welding process on the model to be simulated after the assignment includes: Based on a first preset force loading condition, force loading processing is performed on the fixture model at a first time point, wherein the direction of force loading in the first preset force loading condition is perpendicular to the direction of the sheet metal mid-surface model; Based on a second preset force loading condition, force loading processing is performed on the welding gun model at a second time point, wherein the direction of force loading in the second preset force loading condition is perpendicular to the direction of the sheet metal mid-surface model, and the duration between the second time point and the first time point is the first preset duration; Based on a preset heat loading condition, heat loading is performed on the weld nugget model corresponding to the target weld point at a third time point, wherein the duration between the third time point and the second time point is a second preset duration; Establishing a binding contact relationship between the weld core model and the sheet metal mid-surface model at a fourth time point, wherein the time length between the fourth time point and the third time point is a third preset time length; thermally unloading the weld core model corresponding to the target weld point at a fifth time point, wherein the duration between the fifth time point and the fourth time point is a fourth preset duration; At a sixth time point, force unloading is performed on the welding gun model, wherein the time length between the sixth time point and the fifth time point is a fifth preset time length; The fixture model is force unloaded at a seventh time point, wherein a time period between the seventh time point and the sixth time point is a sixth preset time period.

3. The welding optimization method according to claim 2, characterized in that: The force loading process on the fixture model comprises: A force loading process is performed on a first preset node in the surface mesh corresponding to the fixture model.

4. The welding optimization method according to claim 2, characterized in that: The force loading process on the welding gun model comprises: A force loading process is performed on a second preset node of the surface mesh corresponding to the welding gun model.

5. The welding optimization method according to claim 2, characterized in that: The step of performing heat loading processing on the weld nugget model corresponding to the target weld point comprises: A heat loading process is performed on the body mesh corresponding to the weld core model.

6. The welding optimization method according to claim 1, characterized in that: The optimizing process of the welding simulation of the plurality of first welding points based on the welding deformation amount includes: Based on the welding deformation amount and the preset deformation amount threshold, the welding simulation process of the plurality of first welding points is optimized.

7. The welding optimization method according to claim 6, characterized in that: The optimizing process of the welding simulation process of the plurality of first welding points based on the welding deformation amount and the preset deformation amount threshold comprises: When the welding deformation amount is greater than or equal to the preset deformation amount threshold, the preset welding sequence is adjusted until the welding deformation amount is less than the preset deformation amount threshold.

8. The welding optimization method according to claim 6, characterized in that: The optimizing process of the welding simulation process of the plurality of first welding points based on the welding deformation amount and the preset deformation amount threshold comprises: When the welding deformation amount is greater than or equal to the preset deformation amount threshold, the position of the first welding point is adjusted until the welding deformation amount is less than the preset deformation amount threshold.

9. The welding optimization method according to claim 1, characterized in that: The weld core model has a cylindrical structure, and the axial length of the cylindrical structure is equal to half of the sum of the thicknesses of two adjacent sheet metal models corresponding to the weld core model.

10. The welding optimization method according to claim 1, characterized in that: The fixture model and the welding gun model both have a cylindrical structure.

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