Spot welding topology design and optimization system and method

Abstract

The invention relates to the technical field of topological optimization, in particular to a spot welding topological design and optimization system and method, and the system comprises a welding spot density regulation and control module, a welding heat input adjustment module, a welding spot spacing adaptation module, a welding spot stress detection module and a welding structure optimization module. According to the method, the distance and number of the welding spots are optimized through accurate recognition of the stress categories of the welding spots and bearing analysis, the overall stress balance of the structure is improved, the welding sequence is optimized, temperature fluctuation is reduced, the fatigue life of the welding spots is prolonged, the heat accumulation influence is reduced, and the distance between the welding spots is dynamically adjusted according to the stress gradient, the local bearing capacity and the material utilization rate are optimized; welding spot connection is optimized through stress transfer path analysis, stress concentration is avoided, stability is improved, welding spot topological structure adjustment is based on a load transfer path, the structural rigidity, strength and lightweight level are improved, the adaptability and economic benefits of a spot welding structure are enhanced, the welding spot distribution adaptability is enhanced through a multi-level optimization strategy, and the welding quality is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of topology optimization, and in particular to a spot welding topology design and optimization system and method. Background Art

[0002] The field of topology optimization technology involves using mathematical optimization methods to improve structural design in order to enhance mechanical properties, reduce material consumption, and optimize manufacturing costs. The core content of this technical field is to optimize material distribution through computational methods based on a given design space, load conditions, and constraint requirements, so that the structure can achieve optimal performance while meeting the design objectives. Topology optimization is widely used in mechanical engineering, aerospace, automotive manufacturing, civil engineering, and other fields. It mainly involves computational strategies such as density method, transformation method, and hierarchical optimization method, and relies on numerical calculation methods such as finite element analysis for solution. The current development direction of the technology covers multi-scale optimization, additive manufacturing adaptive optimization, and multi-physics field coupling optimization, etc., to meet the needs of complex structures and extreme working conditions.

[0003] The spot welding topology design and optimization system is a system that optimizes the location, quantity, and distribution of welds in spot welding structures based on topology optimization theory to enhance structural strength, reduce weld redundancy, and improve connection performance. The system primarily involves weld topology optimization calculations, finite element analysis modeling, and parametric design of weld distribution. A finite element model is established based on the body-in-white structure or other spot-welded components, and the influence weights of key welds are calculated under different loads and boundary conditions. A topology optimization algorithm is used to identify weld areas that have a significant impact on structural stiffness and strength, and redundant welds are eliminated. Combined with a weld distribution optimization strategy, the weld location and spacing are adjusted through a parametric model to achieve an optimized weld topology.

[0004] Existing technologies mainly rely on static analysis in the process of weld topology optimization, and lack adaptive adjustment for changes in working conditions, resulting in the inability of weld arrangement to effectively cope with different stress environments. The optimization of the welding sequence does not fully combine the heat input balancing strategy, which easily leads to temperature gradient imbalance during the welding process, resulting in excessive local thermal stress in the weld, affecting the welding quality. The adjustment of weld spacing is based on the topology optimization results, but is not combined with the stress gradient for dynamic adaptation, resulting in insufficient load-bearing capacity of welds in high-stress areas and excessive density of welds in low-stress areas, affecting the rationality of weld distribution. The adjustment of weld connection methods is not combined with stress transfer path analysis, resulting in uneven load distribution in local high-stress areas and increased fatigue damage risk. The lack of targeted adjustment of the load transfer path in weld topology optimization makes the structure insufficiently adaptable under complex working conditions and makes it difficult to meet the comprehensive requirements of weld optimization for strength, stiffness and lightweight. Summary of the Invention

[0005] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a spot welding topology design and optimization system and method.

[0006] In order to achieve the above object, the present invention adopts the following technical solution: a spot welding topology design and optimization system includes:

[0007] The solder joint density control module obtains the stress category of the solder joint, analyzes the load condition, calls the solder joint distribution balance parameters, adjusts the solder joint spacing and quantity, sets the density limit, allocates the solder joint distribution area, corrects the load distribution, and obtains the optimized solder joint density value;

[0008] The welding heat input adjustment module obtains welding sequence information, analyzes heat input changes, screens abnormal heat input areas, adjusts welding paths, balances welding energy distribution, controls temperature fluctuations, and obtains welding heat input optimization values based on the weld spot density optimization value;

[0009] The solder point spacing adaptation module analyzes the relationship between solder point spacing and stress gradient based on the welding heat input optimization value, calls the solder point connection stress data, adjusts the solder point spacing, and sets the stress gradient area threshold, narrows the spacing in the high stress gradient area, and widens the spacing in the low stress gradient area, identifies the uniform distribution state of the solder points, and obtains the solder point spacing adaptation value;

[0010] The solder joint stress detection module obtains the solder joint stress transmission path based on the solder joint spacing adaptation value, analyzes the local stress condition, screens the stress abnormality area, calculates the solder joint load difference, adjusts the connection method, corrects the load distribution, and obtains the solder joint stress distribution parameters.

[0011] As a further solution of the present invention, the weld density optimization value includes weld spacing parameters, weld density threshold, weld load distribution coefficient, and weld connection correction data; the welding heat input optimization value includes welding path parameters, heat input balance coefficient, temperature fluctuation control value, and welding energy distribution data; the weld spacing adaptation value includes spacing adjustment range, stress gradient threshold, local load balance parameter, and weld distribution structure parameter; the weld stress distribution parameter includes stress transfer path, local load difference value, connection optimization parameter, and stress concentration correction coefficient.

[0012] As a further solution of the present invention, the solder point density control module includes:

[0013] The weld stress analysis submodule obtains the spot weld topology design, calls the weld connection node data, analyzes the stress conditions of the weld under different working conditions, calculates the load ratio of the weld in the direction of different loads, selects welds with load ratios lower than the weld load threshold, identifies the force distribution balance relationship between welds, and generates the weld load balance coefficient;

[0014] The solder point distribution adjustment submodule calls the solder point distribution balancing parameter based on the solder point load balancing coefficient, adjusts the solder point spacing, screens the density exceeding the limit area, allocates the solder point distribution area, calculates the adjusted solder point density, and generates the solder point distribution density value;

[0015] The solder point load optimization submodule identifies the solder point load distribution based on the solder point distribution density value, screens the offset exceeding limit area, adjusts the solder point load distribution, calculates the optimized solder point density, and generates the solder point density optimization value.

[0016] As a further solution of the present invention, the welding heat input adjustment module includes:

[0017] The welding heat accumulation analysis submodule obtains welding sequence information based on the weld density optimization value, analyzes the welding heat input changes in the weld area, calculates the heat accumulation index during the welding process, screens the weld heat input abnormal area, identifies the heat input deviation in the abnormal area, and generates the welding heat input deviation value;

[0018] The welding path adjustment submodule calls the welding sequence adjustment parameters based on the welding heat input deviation value, analyzes the welding path sorting optimization, adjusts the welding path distribution, screens the heat input difference of the weld points after the path change, and generates the welding path optimization value;

[0019] The welding temperature control submodule calls the welding heat distribution balancing parameter based on the welding path optimization value, calculates the welding energy distribution index, screens the temperature fluctuation range of the heat input area, adjusts the welding energy output, and generates the welding heat input optimization value.

[0020] As a further solution of the present invention, the solder joint spacing adaptation module includes:

[0021] The solder joint stress analysis submodule analyzes the relationship between solder joint spacing and stress gradient based on the welding heat input optimization value, selects the solder joint spacing adjustment range, calls the solder joint connection stress data, analyzes the local load of the solder joint, selects the high stress gradient area, and calculates and generates the solder joint spacing adjustment index;

[0022] The solder point spacing adjustment submodule sets a stress gradient region threshold based on the solder point spacing adjustment index, reduces the solder point spacing in the high stress gradient region, widens the solder point spacing in the low stress gradient region, calculates the adjusted solder point spacing value, and generates a solder point spacing adjustment result;

[0023] The solder point distribution optimization submodule calls the solder point distribution structural parameters based on the solder point spacing adjustment result, identifies the uniform distribution of solder points under differentiated stress states, calculates the optimized solder point arrangement density, and generates a solder point spacing adaptation value.

[0024] As a further solution of the present invention, the calculation formula of the solder joint spacing adjustment index is specifically:

[0025]

[0026] Among them, D adj Represents the solder joint spacing adjustment index, D avg Represents the average solder joint spacing in the solder joint area, S i Represents the local stress gradient value of the i-th solder joint, S avg represents the average stress gradient value of the solder joint area, n represents the total number of solder joints in the solder joint area, S max Represents the maximum stress gradient value of the solder joint in the solder joint area.

[0027] As a further solution of the present invention, the solder joint stress detection module includes:

[0028] The solder joint stress analysis submodule obtains the solder joint stress transfer path based on the solder joint spacing adaptation value, analyzes the local stress condition of the solder joint, screens the areas with abnormal stress changes in the solder joint, calls the solder joint strength distribution data, calculates the solder joint load difference value, screens the high stress concentration area, and calculates and generates the stress gradient distribution index;

[0029] The solder joint connection optimization submodule adjusts the connection mode of the solder joint based on the stress gradient distribution index, calculates the stress index of the solder joint connection after adjustment, selects the solder joint area with the changed connection mode, analyzes the balance degree of the solder joint connection after optimization, and generates the solder joint connection balance value;

[0030] The solder point load correction submodule calls the solder point stress distribution measurement value based on the solder point connection balance value, corrects the solder point load distribution method, calculates the adjusted solder point load gradient value, screens the load change abnormal area, and generates the solder point stress distribution parameters.

[0031] As a further solution of the present invention, the calculation formula of the solder joint load difference value is specifically:

[0032]

[0033] Among them, C cd Represents the difference in solder joint load, F j Represents the actual load-bearing capacity of the jth solder joint, F mean represents the average load-bearing capacity of the solder joint area, m represents the total number of solder joints in the solder joint area, and F peak Represents the maximum load-bearing capacity of the solder joint area, G j Represents the local stress gradient value of the jth solder joint, G mean Represents the average stress gradient value in the solder joint area.

[0034] As a further solution of the present invention, the system further includes a welding structure optimization module:

[0035] The welding structure optimization module analyzes the distribution state of the welding points in the overall structure based on the welding point stress distribution parameters, adjusts the topological density and arrangement of the welding points, optimizes the load transfer, balances the topological structure, and obtains the welding structure optimization results;

[0036] The welding structure optimization results include welding point topology density, load transfer parameters, welding point arrangement correction value, and topology balance adjustment factor;

[0037] The welding structure optimization module includes:

[0038] The welding load analysis submodule analyzes the distribution of the welds in the overall weld structure based on the weld stress distribution parameters, obtains the welding load transfer status, screens areas with abnormal weld topology, calls the weld structure stress distribution data, calculates the load distribution difference value, screens the load concentration area, and generates the welding load balancing result;

[0039] The solder joint topology adjustment submodule calls the topology distribution adjustment factor based on the welding load balancing result, adjusts the solder joint topology density, calculates the solder joint stress distribution after the topology density change, screens the topology balance change area, and generates the solder joint topology adjustment value;

[0040] The solder joint distribution optimization submodule adjusts the value based on the solder joint topology, calls the topology structure balance parameter, adjusts the solder joint distribution pattern, calculates the solder joint arrangement density change index, screens the solder joint force balance distribution area, and generates the welding structure optimization result.

[0041] A spot welding topology design and optimization method comprises the following steps:

[0042] S1: Obtain the stress category of the weld, analyze the load-bearing conditions of the weld under different working conditions, call the weld distribution balance parameters, calculate the weld spacing and number, set the weld density limit value, allocate the weld distribution area, call the weld connection node data, adjust the load distribution between welds, and obtain the weld density optimization value;

[0043] S2: Based on the optimized value of the weld density, obtain welding sequence information, analyze the welding heat input distribution in the weld area, calculate the heat accumulation index during the welding process, screen the abnormal heat input area, call the welding sequence adjustment parameters, reorder the welding path, identify the welding energy distribution state, adjust the temperature fluctuation of the heat input area, and obtain the optimized welding heat input value;

[0044] S3: Based on the welding heat input optimization value, analyze the trend of the solder joint spacing and stress gradient change, select the solder joint spacing adjustment range, call the solder joint connection stress data, calculate the local load of the solder joint, compare the stress gradient change between the solder joints, set the stress gradient area threshold, reduce the solder joint spacing in the high stress gradient area, relax the solder joint spacing in the low stress gradient area, call the solder joint distribution structure parameters, optimize the stress balance state of the solder joints, and obtain the solder joint spacing adaptation value;

[0045] S4: Based on the solder joint spacing adaptation value, obtain the solder joint stress transfer path, analyze the local stress condition of the solder joint, screen the area with abnormal stress change, call the solder joint strength distribution data, calculate the solder joint load difference value, identify the high stress concentration area, adjust the solder joint connection method, optimize the stress balance state of the solder joint, and obtain the solder joint stress distribution parameters;

[0046] S5: Based on the stress distribution parameters of the weld points, analyze the distribution of the weld points in the overall weld structure, obtain the welding load transfer characteristics, screen the abnormal areas of the weld point topology structure, call the topology distribution adjustment factor, optimize the weld point topology density, correct the weld point arrangement, call the topology structure balance parameter, optimize the weld point distribution pattern, and obtain the weld structure optimization result.

[0047] Compared with the prior art, the advantages and positive effects of the present invention are:

[0048] In the present invention, the spacing and number of welds are optimized through accurate identification of the stress categories of welds and load analysis, thereby improving the overall stress balance of the structure, optimizing the welding sequence to reduce temperature fluctuations, increasing the fatigue life of welds, and reducing the impact of heat accumulation, and dynamically adjusting the weld spacing according to the stress gradient to optimize the local bearing capacity and material utilization, and optimizing the weld connection through stress transfer path analysis to avoid stress concentration and improve stability, and adjusting the weld topology structure based on the load transfer path to improve the structural stiffness, strength and lightweight level, thereby enhancing the adaptability and economic benefits of the spot welding structure, and a multi-level optimization strategy to enhance the adaptability of weld distribution and improve welding quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 is a system flow chart of the present invention;

[0050] Figure 2 It is a submodule flow chart of the present invention;

[0051] Figure 3 This is a flow chart of the solder joint density control module of the present invention;

[0052] Figure 4 This is a flow chart of the welding heat input adjustment module of the present invention;

[0053] Figure 5 This is a flow chart of the solder joint spacing adaptation module of the present invention;

[0054] Figure 6 This is a flow chart of the solder joint stress detection module of the present invention;

[0055] Figure 7 This is a flow chart of the welding structure optimization module of the present invention;

[0056] Figure 8 The figure is a flow chart of the steps of the method of the present invention. DETAILED DESCRIPTION

[0057] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0058] In the description of the present invention, it should be understood that the terms "length," "width," "up," "down," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inside," "outside," and the like, indicating positions or relationships, are based on the positions or relationships shown in the accompanying drawings and are intended only to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limiting the present invention. Furthermore, in the description of the present invention, "plurality" means two or more, unless otherwise expressly and specifically defined.

[0059] See also Figure 1 and Figure 2 , a spot welding topology design and optimization system includes:

[0060] The solder joint density control module obtains the stress category of solder joints in the spot welding topology design and optimization, analyzes the load-bearing conditions of solder joints under different working conditions, calls solder joint distribution balancing parameters, adjusts the spacing and number of solder joints, sets the density limit of solder joints, allocates solder joint distribution areas, calls solder joint connection node data, performs correlation correction processing on the adjusted solder joint areas, adjusts the load distribution between solder joints, and obtains the optimized solder joint density value;

[0061] The welding heat input adjustment module optimizes the solder joint density value, obtains welding sequence information, analyzes the welding heat input changes in the solder joint area, calculates the heat accumulation index during the welding process, screens the areas with abnormal solder joint heat input, calls the welding sequence adjustment parameters, reorders the welding paths, identifies the welding energy distribution based on the welding heat distribution balance parameters, controls the temperature fluctuations in the heat input area, and obtains the optimized welding heat input value;

[0062] The solder joint spacing adaptation module optimizes the welding heat input value, analyzes the relationship between solder joint spacing and stress gradient, selects the solder joint spacing adjustment range, calls the solder joint connection stress data, obtains the local load of the solder joint, calculates the solder joint spacing adjustment index, and sets the stress gradient area threshold. It reduces the solder joint spacing in high stress gradient areas and relaxes the solder joint spacing in low stress gradient areas. It calls the solder joint distribution structure parameters, identifies the uniform distribution of solder joints under differentiated stress conditions, and obtains the solder joint spacing adaptation value.

[0063] The solder joint stress detection module obtains the solder joint stress transmission path based on the solder joint spacing adaptation value, analyzes the local stress condition of the solder joint, screens the areas with abnormal stress changes in the solder joint, calls the solder joint strength distribution data, calculates the solder joint load difference value, screens the high stress concentration areas, adjusts the solder joint connection method, optimizes the solder joint force balance, calls the solder joint stress distribution measurement value, corrects the solder joint load distribution method, and obtains the solder joint stress distribution parameters;

[0064] The welding structure optimization module analyzes the distribution status of welds in the overall welding structure based on the weld stress distribution parameters, obtains the welding load transfer situation, screens the abnormal areas of weld topology, calls the topology distribution adjustment factor, adjusts the weld topology density, and corrects the weld arrangement. It calls the topology structure balance parameter, adjusts the weld distribution pattern, and obtains the welding structure optimization results.

[0065] The weld density optimization value includes weld spacing parameters, weld density threshold, weld load distribution coefficient, and weld connection correction data; the welding heat input optimization value includes welding path parameters, heat input balance coefficient, temperature fluctuation control value, and welding energy distribution data; the weld spacing adaptation value includes spacing adjustment range, stress gradient threshold, local load balance parameter, and weld distribution structure parameter; the weld stress distribution parameter includes stress transfer path, local load difference value, connection optimization parameter, and stress concentration correction coefficient; the welding structure optimization result includes weld topology density, load transfer parameter, weld arrangement correction value, and topology balance adjustment factor.

[0066] See also Figure 3 and Figure 2 , the solder joint density control module includes:

[0067] The weld stress analysis submodule obtains the spot weld topology design, calls the weld connection node data, analyzes the stress conditions of the weld under different working conditions, calculates the load ratio of the weld in the direction of different loads, selects welds with load ratios lower than the weld load threshold, identifies the force distribution balance relationship between welds, and generates the weld load balance coefficient;

[0068] Obtain the spot welding topology design and call the weld connection node data to extract the weld coordinate information, material properties of the connected panels, weld spacing and stress conditions in the weld area. For the stress conditions of the weld under different working conditions, first read the load data, including static load, dynamic impact load and thermal expansion stress, etc., and apply the external force value of the corresponding working condition to the node where the weld is located, calculate the stress state of a single weld, including normal stress and shear stress, call the material parameters of the area where the weld is located, such as yield strength and ultimate strength, and calculate the bearing capacity of a single weld. Express the bearing ratio of a single weld in the form of a bearing capacity ratio, perform vector decomposition of the bearing capacity of the weld in different load directions, and obtain the bearing ratio in different directions. The load ratio of the weld under the comprehensive force is calculated based on the direction vector, and the weld load ratio is compared with the set weld load threshold, where the weld load threshold is determined according to the material type, weld diameter, and welding method. For example, for ordinary steel plate welding with a weld diameter of 5 mm, the load threshold can be 0.6 times the ultimate shear stress. Welds with a load ratio lower than the threshold are screened out. For the screened welds, the force balance between the welds is further calculated, the force changes of adjacent welds are counted, the force standard deviation between adjacent welds is calculated, and the weld load balance coefficient is calculated by dividing the standard deviation by the average force value. If the coefficient is greater than 0.15, it is considered that the weld force distribution is uneven, and the weld load balance coefficient is finally obtained.

[0069] The solder point distribution adjustment submodule calls the solder point distribution balancing parameters based on the solder point load balancing coefficient, adjusts the solder point spacing, screens the density exceeding the limit area, allocates the solder point distribution area, calculates the adjusted solder point density, and generates the solder point distribution density value;

[0070] The solder joint distribution balancing parameters are called, where the balancing parameters include the minimum spacing of solder joints, the maximum spacing of solder joints, the average spacing of solder joints, etc. The solder joint spacing data is extracted, and the stress conditions of the solder joints are partitioned. The solder joints are sorted according to the stress magnitude, and the density of solder joints in the area with greater stress is calculated. If the solder joint spacing is less than the minimum spacing (for example, 2mm), the area is marked as a high-density area. If the solder joint spacing is greater than the maximum spacing (for example, 10mm), the area is marked as a low-density area. When calculating the solder joint density, the number of solder joints per unit area is used for measurement. For example, if there are 10 solder joints in an area of 100mm×100mm, the solder joint density is 0.1 / mm 2 , screen out the density-exceeding areas, and adjust the solder joint spacing according to the solder joint load balance coefficient. In the high-density area, reduce the density by removing some solder joints with low load ratios, and calculate the adjusted solder joint density. In the low-density area, increase the density by adding solder joints in the area with greater stress, and calculate the adjusted solder joint density, and finally obtain the adjusted solder joint distribution density value.

[0071] The solder point load optimization submodule identifies the solder point load distribution based on the solder point distribution density value, screens the offset exceeding limit area, adjusts the solder point load distribution, calculates the optimized solder point density, and generates the solder point density optimization value;

[0072] Extract the stress data of the weld point, calculate the stress concentration degree of a single weld point, and screen out the area where the stress offset exceeds the limit. The judgment of the offset exceeding the limit is based on the load concentration degree of the weld point. If the stress of the weld point exceeds 1.5 times the average stress of the area, it is judged as the offset exceeding the limit. Based on this judgment, the area where the weld point is located is divided into high-load area and low-load area, and the load gradient is calculated. The area where the stress gradient between weld points is greater than 0.2 times the average stress is marked as the area to be optimized. During the optimization process, adjust the position of the weld point so that the weld point density in the high-load area is appropriately reduced, and allocate some weld points to the low-load area. Calculate the optimized weld point density value. If the optimized weld point density value meets the design requirements (for example, the density variation does not exceed 10%), the optimization is completed, and finally the optimized weld point density value is obtained.

[0073] See also Figure 4 and Figure 2 , welding heat input adjustment module includes:

[0074] The welding heat accumulation analysis submodule optimizes the value of the solder joint density, obtains the welding sequence information, analyzes the welding heat input changes in the solder joint area, calculates the heat accumulation index during the welding process, screens the solder joint heat input abnormal areas, identifies the heat input deviation in the abnormal area, and generates the welding heat input deviation value;

[0075] The welding sequence information is obtained, where the welding sequence information includes the welding order of the welds, the welding time interval and the welding current setting. The welding parameters of the weld area, including the welding current, welding voltage and welding time, are extracted, and the heat input of each weld is calculated. The thermal conductivity characteristic parameters of the weld area, such as the thermal conductivity and specific heat capacity of the material, are called, the diffusion of heat in the weld area during welding is analyzed, and the heat input change of the weld area is determined. For the first n welds in the welding sequence, the heat input is cumulatively calculated and compared with the average heat input value in the area. If the cumulative heat input of a certain area is higher than 20% of the average value, the area is marked as an abnormal welding heat input area. In the abnormal area, the local temperature distribution of the weld is extracted, and the deviation ratio between the maximum and minimum heat input values is calculated. If the deviation ratio exceeds 30%, it is determined that there is a significant heat input deviation in the area, and finally the welding heat input deviation value is obtained.

[0076] The welding path adjustment submodule calls the welding sequence adjustment parameters based on the welding heat input deviation value, analyzes the welding path sorting optimization, adjusts the welding path distribution, screens the heat input differences of the solder points after the path change, and generates the welding path optimization value;

[0077] The welding sequence adjustment parameters are called, where the welding sequence adjustment parameters include the minimum time interval between solder points, the temperature gradient threshold of adjacent solder points, etc. According to the welding sequence adjustment parameters, the welding path sorting optimization is analyzed, the current welding path information is extracted, and the temperature change between solder points is calculated. The areas where the temperature change rate exceeds the set threshold are screened. For example, if the temperature change rate of adjacent solder points exceeds 10℃ / s, the welding sequence needs to be adjusted. During the adjustment process, the welding sequence of the solder points is rearranged so that the high-temperature area and the low-temperature area are welded alternately to reduce local overheating. At the same time, the heat input value of the adjusted solder point is calculated. If the heat input fluctuation range of the adjusted solder point is less than 10%, the welding path optimization is determined to be completed, and the welding path optimization value is finally obtained.

[0078] The welding temperature control submodule uses the welding heat distribution balance parameters based on the welding path optimization value, calculates the welding energy distribution index, screens the temperature fluctuation range of the heat input area, adjusts the welding energy output, and generates the welding heat input optimization value;

[0079] Call welding heat distribution balancing parameters, which include welding energy input upper limit, welding area temperature fluctuation range, etc., extract welding energy input data, calculate the temperature change of the solder joint area, and screen out areas with temperature fluctuation exceeding the limit. For example, if the temperature fluctuation of a certain area exceeds 5°

[0080] C / s, the welding energy input needs to be adjusted. During the adjustment process, the temperature fluctuation rate in the weld area can be reduced to within the allowable range by reducing the welding current, increasing the welding dwell time or welding in steps, and finally the optimized welding heat input value is obtained.

[0081] See also Figure 5 and Figure 2 , the solder joint spacing adaptation module includes:

[0082] The solder joint stress analysis submodule optimizes the welding heat input value, analyzes the relationship between solder joint spacing and stress gradient, selects the solder joint spacing adjustment range, calls the solder joint connection stress data, analyzes the local load of the solder joint, selects the high stress gradient area, and calculates and generates the solder joint spacing adjustment index;

[0083] The calculation formula for the solder joint spacing adjustment index is as follows:

[0084]

[0085] Among them, D adj Represents the solder joint spacing adjustment index, D avg Represents the average solder joint spacing in the solder joint area, S i Represents the local stress gradient value of the i-th solder joint, S avgrepresents the average stress gradient value of the solder joint area, n represents the total number of solder joints in the solder joint area, S max Represents the maximum stress gradient value of the solder joint in the solder joint area;

[0086] Set up example data: Assume that there are 10 solder joints in the solder joint area. Through actual measurement, the local stress gradient S of the solder joint i are [15, 20, 25, 30, 10, 5, 50, 45, 35, 25] MPa / m. Then S avg and S max The calculation of is as follows:

[0087] The current average solder joint spacing D avg Set to 5mm. The calculation process of the adjustment coefficient is as follows:

[0088] Adjustment coefficient calculation:

[0089]

[0090] Solder point spacing adjustment:

[0091] D adj =5×0.776=3.88mm;

[0092] The calculations show that the weld spacing adjustment index is 3.88 mm. This result means that in areas with large stress gradients, the weld spacing needs to be reduced to enhance structural stability, ensure uniform stress distribution, and thus improve the overall performance of the welded structure. In this way, the weld spacing adjustment index directly affects the ultimate strength and durability of the welded structure.

[0093] The solder joint spacing adjustment submodule sets the stress gradient region threshold based on the solder joint spacing adjustment index, reduces the solder joint spacing in the high stress gradient region, and widens the solder joint spacing in the low stress gradient region. It calculates the adjusted solder joint spacing value and generates the solder joint spacing adjustment result.

[0094] The stress data of the area where the solder joint is located is called, and the area is divided into a high stress gradient area and a low stress gradient area according to the set stress gradient area threshold. In the high stress gradient area, the current solder joint spacing data is extracted to determine whether the solder joint spacing is greater than the minimum allowable value (such as 3mm). If it is greater than the minimum allowable value, the solder joint spacing is appropriately reduced, the solder joint spacing after reduction is calculated, and the stress change of the solder joint after adjustment is verified. In the low stress gradient area, the solder joint distribution data is extracted to determine whether the solder joint spacing is less than the maximum allowable value (such as 10mm). If it is less than the maximum allowable value, the solder joint spacing is appropriately relaxed, and the adjusted solder joint spacing value is calculated. During the adjustment process, the total number of solder joints is kept unchanged to ensure that the stress gradient between the solder joints tends to be balanced after adjustment, and the final solder joint spacing adjustment result is calculated.

[0095] The solder point distribution optimization submodule uses the solder point distribution structural parameters based on the solder point spacing adjustment results, identifies the uniform distribution of solder points under differentiated stress conditions, calculates the optimized solder point arrangement density, and generates the solder point spacing adaptation value;

[0096] Call the solder point distribution structural parameters, extract the adjusted solder point coordinate data, calculate the mean solder point arrangement spacing, analyze the distribution of solder points under differentiated stress states, calculate the solder point density distribution for the stress concentrated area, and screen the areas with uneven solder point arrangement density. In the high density area, calculate the stress gradient of adjacent solder points. If the solder point stress gradient is lower than the set value (such as 10%), the solder points in the area are judged to be redundant, and the solder point arrangement is appropriately adjusted. In the low density area, calculate the solder point force change rate. If the rate exceeds the threshold (such as 15%), increase the solder point distribution density, and calculate the optimized solder point arrangement density to finally generate the solder point spacing adaptation value.

[0097] See also Figure 6 and Figure 2 , the solder joint stress detection module includes:

[0098] The solder joint stress analysis submodule obtains the solder joint stress transfer path based on the solder joint spacing adaptation value, analyzes the local stress conditions of the solder joint, screens areas with abnormal solder joint stress changes, calls solder joint strength distribution data, calculates solder joint load difference values, screens high stress concentration areas, and calculates and generates stress gradient distribution indicators;

[0099] The calculation formula of the solder joint load difference value is as follows:

[0100]

[0101] Among them, C cd Represents the difference in solder joint load, F j Represents the actual load-bearing capacity of the jth solder joint, F mean represents the average load-bearing capacity of the solder joint area, m represents the total number of solder joints in the solder joint area, and F peak Represents the maximum load-bearing capacity of the solder joint area, G j Represents the local stress gradient value of the jth solder joint, G mean Represents the average stress gradient value of the solder joint area;

[0102] The formula is used to calculate the load difference value C of the solder joint cd , which reflects the stress uniformity of the weld in the structure. This formula takes into account the difference between the actual load-bearing capacity of the weld and its average value, as well as the discreteness of the stress gradient.

[0103] Set specific values to perform calculations:

[0104] Assume that the solder joint area has 5 solder joints.

[0105] The actual load-bearing capacity F of each welding point j , obtained through actual testing:

[0106] [1000N,950N,1200N,1100N,900N].

[0107] Average bearing capacity F mean Calculated as:

[0108] Maximum load capacity F peak The maximum value among these values is 1200N.

[0109] The stress gradient value G of each solder joint j Obtained through actual stress analysis:

[0110] [5MPa / m, 4.5MPa / m, 6MPa / m, 5.5MPa / m, 4MPa / m].

[0111] Average stress gradient G mean Calculated as:

[0112] Calculate the load difference value C cd :

[0113] Numerators sum for F j -F mean =|1000-1030|+|950-1030|+|1200-1030|+|1100-1030|+|900-1030|=30+80+170+70+130=480;

[0114] NumeratorforG j -G mean =(5-5) 2 +(4.5-5) 2 +(6-5) 2 +(5.5-5) 2 +(4-5) 2 =0+0.25+1+0.25+1=2.5;

[0115]

[0116] The results show that the load-bearing difference value of the weld is 0.0500, indicating that the weld has minimal nonuniformity in stress and load-bearing capacity. This value can be used to evaluate the stress uniformity of welded structures and guide the optimization of weld layout and welding processes, thereby improving the overall stability and reliability of the structure.

[0117] The solder joint connection optimization submodule adjusts the solder joint connection method based on the stress gradient distribution index, calculates the stress index of the adjusted solder joint connection, screens the solder joint areas with changed connection methods, analyzes the balance of the optimized solder joint connection, and generates the solder joint connection balance value;

[0118] Extract the connection method data of the solder joint, calculate the connection stress of the current solder joint, and judge whether the connection method needs to be adjusted. In the area with higher stress gradient, screen the solder joints with concentrated stress, and analyze the connection status of the solder joint. If the solder joint connection method is single-sided lap welding and the stress gradient exceeds 20%, it is adjusted to double-sided lap welding to reduce local stress concentration. In the area with lower stress gradient, screen the solder joints with smaller stress, and judge whether the solder joint connection method needs to be simplified. For example, if the solder joint adopts double-sided welding, but the stress gradient is less than 5%, it can be adjusted to single-sided welding to optimize the use efficiency of the solder joint. Calculate the stress index of the solder joint connection after adjustment, screen the solder joint area where the connection method changes, and compare the stress balance of the solder joint connection before and after optimization. Calculate the connection balance coefficient. If the optimized balance coefficient is less than 1.2, it is judged that the stress balance of the solder joint connection is good, and finally obtain the solder joint connection balance value.

[0119] The solder point load correction submodule uses the solder point stress distribution measurement value based on the solder point connection equilibrium value, corrects the solder point load distribution method, calculates the adjusted solder point load gradient value, screens the area with abnormal load changes, and generates the solder point stress distribution parameters;

[0120] Extract the measured values of stress distribution of solder joints, calculate the force balance of solder joints, judge whether the load distribution of solder joints meets the regional load requirements, and adjust the load distribution mode of solder joints in areas with uneven load distribution. For example, in high-load areas, if the force of a single solder joint exceeds 1.3 times the average force of the area, appropriately increase solder joints in adjacent areas to disperse local loads. In low-load areas, if the force of solder joints is lower than 0.7 times the average force of the area, appropriately reduce solder joints to optimize material utilization. Calculate the load gradient value of the adjusted solder joints, and screen out areas with abnormal load changes. If the load gradient of the solder joints exceeds the set threshold (such as 20%), further optimize the solder joint position to ensure a more uniform load distribution, and finally obtain the stress distribution parameters of the solder joints.

[0121] See also Figure 7 and Figure 2 , welding structure optimization module includes:

[0122] The welding load analysis submodule analyzes the distribution of welds in the overall weld structure based on the stress distribution parameters of welds, obtains the welding load transfer status, screens areas with abnormal weld topology, calls the stress distribution data of the weld structure, calculates the load distribution difference value, screens the load concentration area, and generates the welding load balancing result;

[0123] Extract the spatial distribution information of the welds, analyze the arrangement of the welds in the overall welded structure, call the structural force data, calculate the stress transfer path of the welds in different force directions, and determine whether the area where the welds are located is located in the main load path, obtain the welding load transfer situation, extract the force flow distribution of the structure where the welds are located, calculate the weld force gradient, and screen the areas with a large load change rate. If the weld force gradient in a certain area is greater than the set threshold (such as 25%), it is determined that there is an abnormal load transfer path in the area, screen the abnormal areas of the weld topology structure, and call the stress distribution data of the welded structure to calculate the difference between the mean and extreme values of the weld force. If the maximum force value exceeds 1.5 times the average force value, the area is marked as an area with uneven load distribution, screen the load concentration area, and calculate the load distribution balance coefficient. If the balance coefficient is lower than 0.8, the weld distribution needs to be adjusted to finally generate the welding load balance result.

[0124] The solder joint topology adjustment submodule calls the topology distribution adjustment factor based on the welding load balancing result, adjusts the solder joint topology density, calculates the solder joint stress distribution after the topology density change, screens the area where the topology balance changes, and generates the solder joint topology adjustment value;

[0125] The current topological density data of the solder joints is extracted, and the topological distribution adjustment factor is called to calculate the distribution density of solder joints in different stress areas. If the solder joint density in a certain area is high and the force is uniform, the original density is kept unchanged. If the solder joint density is high but the local force change rate exceeds 15%, the solder joint density is appropriately reduced. In the load concentration area, if the solder joint density is low and the local force exceeds 1.3 times the average force, the solder joint density is increased. After adjusting the solder joint topological density, the stress distribution of the solder joint after topological adjustment is calculated, the stress balance change area is screened, and the force gradient change rate before and after the topological density adjustment is calculated. If the gradient change rate after adjustment is reduced to within 10%, the topological structure optimization is determined to be effective, and the solder joint topology adjustment value is finally generated.

[0126] The solder joint distribution optimization submodule adjusts the values based on the solder joint topology, calls the topology structure balance parameters, adjusts the solder joint distribution pattern, calculates the solder joint arrangement density change index, screens the solder joint force balance distribution area, and generates the welding structure optimization results;

[0127] Extract the arrangement data of the solder joints, call the topological structure balance parameters, calculate the arrangement density of the current solder joints, and analyze the distribution pattern of the solder joints to determine whether there are areas with uneven force. In areas with high force gradients, if the solder joint arrangement density is lower than the structural load requirement (such as 0.08 / mm 2 ), then appropriately increase the density of solder joints. In the area with low force change rate, if the density of solder joints is higher than the set value (such as 0.15 / mm2 ), the number of welds is appropriately reduced, the weld spacing is readjusted, the weld density after optimization is calculated, and the weld force balanced distribution area is screened. If the force balance coefficient of the optimized weld is higher than 0.9, the weld distribution adjustment is determined to be reasonable, and the welding structure optimization result is finally generated.

[0128] See also Figure 8 , a spot welding topology design and optimization method, comprising the following steps:

[0129] S1: Obtain the stress category of the weld, analyze the load-bearing conditions of the weld under different working conditions, call the weld distribution balance parameters, calculate the weld spacing and number, set the weld density limit value, allocate the weld distribution area, call the weld connection node data, adjust the load distribution between welds, and obtain the weld density optimization value;

[0130] S2: Based on the optimized value of the solder joint density, obtain the welding sequence information, analyze the welding heat input distribution in the solder joint area, calculate the heat accumulation index during the welding process, screen the abnormal heat input area, call the welding sequence adjustment parameters, reorder the welding path, identify the welding energy distribution state, adjust the temperature fluctuation of the heat input area, and obtain the optimized welding heat input value;

[0131] S3: Based on the welding heat input optimization value, analyze the trend of the solder joint spacing and stress gradient change, select the solder joint spacing adjustment range, call the solder joint connection stress data, calculate the local load of the solder joint, compare the stress gradient change between the solder joints, set the stress gradient area threshold, reduce the solder joint spacing in the high stress gradient area, relax the solder joint spacing in the low stress gradient area, call the solder joint distribution structure parameters, optimize the stress balance state of the solder joint, and obtain the solder joint spacing adaptation value;

[0132] S4: Based on the solder joint spacing adaptation value, obtain the solder joint stress transfer path, analyze the local stress condition of the solder joint, screen the area with abnormal stress change, call the solder joint strength distribution data, calculate the solder joint load difference value, identify the high stress concentration area, adjust the solder joint connection method, optimize the stress balance state of the solder joint, and obtain the solder joint stress distribution parameters;

[0133] S5: Based on the stress distribution parameters of the weld points, analyze the distribution of the weld points in the overall weld structure, obtain the welding load transfer characteristics, screen the abnormal areas of the weld point topology structure, call the topology distribution adjustment factor, optimize the weld point topology density, correct the weld point arrangement, call the topology structure balance parameter, optimize the weld point distribution pattern, and obtain the weld structure optimization results.

[0134] The above are merely preferred embodiments of the present invention and do not limit the present invention in any other form. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A spot welding topology design and optimization system, characterized by: The system comprises: The solder joint density control module obtains the stress category of the solder joint, analyzes the load condition, calls the solder joint distribution balance parameters, adjusts the solder joint spacing and quantity, sets the density limit, allocates the solder joint distribution area, corrects the load distribution, and obtains the optimized solder joint density value; The welding heat input adjustment module obtains welding sequence information, analyzes heat input changes, screens abnormal heat input areas, adjusts welding paths, balances welding energy distribution, controls temperature fluctuations, and obtains welding heat input optimization values based on the weld spot density optimization value; The solder point spacing adaptation module analyzes the relationship between solder point spacing and stress gradient based on the welding heat input optimization value, calls the solder point connection stress data, adjusts the solder point spacing, and sets the stress gradient area threshold, narrows the spacing in the high stress gradient area, and widens the spacing in the low stress gradient area, identifies the uniform distribution state of the solder points, and obtains the solder point spacing adaptation value; The solder joint stress detection module obtains the solder joint stress transmission path based on the solder joint spacing adaptation value, analyzes the local stress condition, screens the stress abnormality area, calculates the solder joint load difference, adjusts the connection method, corrects the load distribution, and obtains the solder joint stress distribution parameters.

2. The spot welding topology design and optimization system according to claim 1, characterized in that: The weld density optimization value includes weld spacing parameters, weld density threshold, weld load distribution coefficient, and weld connection correction data; the welding heat input optimization value includes welding path parameters, heat input balance coefficient, temperature fluctuation control value, and welding energy distribution data; the weld spacing adaptation value includes spacing adjustment range, stress gradient threshold, local load balance parameter, and weld distribution structure parameter; the weld stress distribution parameter includes stress transfer path, local load difference value, connection optimization parameter, and stress concentration correction coefficient.

3. The spot welding topology design and optimization system according to claim 1, characterized in that: The solder point density control module includes: The weld stress analysis submodule obtains the spot weld topology design, calls the weld connection node data, analyzes the stress conditions of the weld under different working conditions, calculates the load ratio of the weld in the direction of different loads, selects welds with load ratios lower than the weld load threshold, identifies the force distribution balance relationship between welds, and generates the weld load balance coefficient; The solder point distribution adjustment submodule calls the solder point distribution balancing parameter based on the solder point load balancing coefficient, adjusts the solder point spacing, screens the density exceeding the limit area, allocates the solder point distribution area, calculates the adjusted solder point density, and generates the solder point distribution density value; The solder point load optimization submodule identifies the solder point load distribution based on the solder point distribution density value, screens the offset exceeding limit area, adjusts the solder point load distribution, calculates the optimized solder point density, and generates the solder point density optimization value.

4. The spot welding topology design and optimization system according to claim 1, characterized in that: The welding heat input adjustment module includes: The welding heat accumulation analysis submodule obtains welding sequence information based on the weld density optimization value, analyzes the welding heat input changes in the weld area, calculates the heat accumulation index during the welding process, screens the weld heat input abnormal area, identifies the heat input deviation in the abnormal area, and generates the welding heat input deviation value; The welding path adjustment submodule calls the welding sequence adjustment parameters based on the welding heat input deviation value, analyzes the welding path sorting optimization, adjusts the welding path distribution, screens the heat input difference of the weld points after the path change, and generates the welding path optimization value; The welding temperature control submodule calls the welding heat distribution balancing parameter based on the welding path optimization value, calculates the welding energy distribution index, screens the temperature fluctuation range of the heat input area, adjusts the welding energy output, and generates the welding heat input optimization value.

5. The spot welding topology design and optimization system according to claim 1, characterized in that: The solder joint spacing adaptation module includes: The solder joint stress analysis submodule analyzes the relationship between solder joint spacing and stress gradient based on the welding heat input optimization value, selects the solder joint spacing adjustment range, calls the solder joint connection stress data, analyzes the local load of the solder joint, selects the high stress gradient area, and calculates and generates the solder joint spacing adjustment index; The solder point spacing adjustment submodule sets a stress gradient region threshold based on the solder point spacing adjustment index, reduces the solder point spacing in the high stress gradient region, widens the solder point spacing in the low stress gradient region, calculates the adjusted solder point spacing value, and generates a solder point spacing adjustment result; The solder point distribution optimization submodule calls the solder point distribution structural parameters based on the solder point spacing adjustment result, identifies the uniform distribution of solder points under differentiated stress states, calculates the optimized solder point arrangement density, and generates a solder point spacing adaptation value.

6. The spot welding topology design and optimization system according to claim 5, characterized in that: The calculation formula for the solder joint spacing adjustment index is specifically as follows: Among them, D adj Represents the solder joint spacing adjustment index, D avg Represents the average solder joint spacing in the solder joint area, S i Represents the local stress gradient value of the i-th solder joint, S avg represents the average stress gradient value of the solder joint area, n represents the total number of solder joints in the solder joint area, S max Represents the maximum stress gradient value of the solder joint in the solder joint area.

7. The spot welding topology design and optimization system according to claim 1, characterized in that: The solder point stress detection module includes: The solder joint stress analysis submodule obtains the solder joint stress transfer path based on the solder joint spacing adaptation value, analyzes the local stress condition of the solder joint, screens the areas with abnormal stress changes in the solder joint, calls the solder joint strength distribution data, calculates the solder joint load difference value, screens the high stress concentration area, and calculates and generates the stress gradient distribution index; The solder joint connection optimization submodule adjusts the connection mode of the solder joint based on the stress gradient distribution index, calculates the stress index of the solder joint connection after adjustment, selects the solder joint area with the changed connection mode, analyzes the balance degree of the solder joint connection after optimization, and generates the solder joint connection balance value; The solder point load correction submodule calls the solder point stress distribution measurement value based on the solder point connection balance value, corrects the solder point load distribution method, calculates the adjusted solder point load gradient value, screens the load change abnormal area, and generates the solder point stress distribution parameters.

8. The spot welding topology design and optimization system according to claim 7, characterized in that: The calculation formula of the solder joint load difference value is specifically: Among them, C cd Represents the difference in solder joint load, F j Represents the actual load-bearing capacity of the jth solder joint, F mean represents the average load-bearing capacity of the solder joint area, m represents the total number of solder joints in the solder joint area, and F peak Represents the maximum load-bearing capacity of the solder joint area, G j Represents the local stress gradient value of the jth solder joint, G mean Represents the average stress gradient value in the solder joint area.

9. The spot welding topology design and optimization system according to claim 1, characterized in that: The system also includes a welding structure optimization module: The welding structure optimization module analyzes the distribution state of the welding points in the overall structure based on the welding point stress distribution parameters, adjusts the topological density and arrangement of the welding points, optimizes the load transfer, balances the topological structure, and obtains the welding structure optimization results; The welding structure optimization results include welding point topology density, load transfer parameters, welding point arrangement correction value, and topology balance adjustment factor; The welding structure optimization module includes: The welding load analysis submodule analyzes the distribution of the welds in the overall weld structure based on the weld stress distribution parameters, obtains the welding load transfer status, screens areas with abnormal weld topology, calls the weld structure stress distribution data, calculates the load distribution difference value, screens the load concentration area, and generates the welding load balancing result; The solder joint topology adjustment submodule calls the topology distribution adjustment factor based on the welding load balancing result, adjusts the solder joint topology density, calculates the solder joint stress distribution after the topology density change, screens the topology balance change area, and generates the solder joint topology adjustment value; The solder joint distribution optimization submodule adjusts the value based on the solder joint topology, calls the topology structure balance parameter, adjusts the solder joint distribution pattern, calculates the solder joint arrangement density change index, screens the solder joint force balance distribution area, and generates the welding structure optimization result.

10. A spot welding topology design and optimization method, characterized in that: The spot welding topology design and optimization system according to any one of claims 1 to 9 comprises the following steps: S1: Obtain the stress category of the weld, analyze the load-bearing conditions of the weld under different working conditions, call the weld distribution balance parameters, calculate the weld spacing and number, set the weld density limit value, allocate the weld distribution area, call the weld connection node data, adjust the load distribution between welds, and obtain the weld density optimization value; S2: Based on the optimized value of the weld density, obtain welding sequence information, analyze the welding heat input distribution in the weld area, calculate the heat accumulation index during the welding process, screen the abnormal heat input area, call the welding sequence adjustment parameters, reorder the welding path, identify the welding energy distribution state, adjust the temperature fluctuation of the heat input area, and obtain the optimized welding heat input value; S3: Based on the welding heat input optimization value, analyze the trend of the solder joint spacing and stress gradient change, select the solder joint spacing adjustment range, call the solder joint connection stress data, calculate the local load of the solder joint, compare the stress gradient change between the solder joints, set the stress gradient area threshold, reduce the solder joint spacing in the high stress gradient area, relax the solder joint spacing in the low stress gradient area, call the solder joint distribution structure parameters, optimize the stress balance state of the solder joints, and obtain the solder joint spacing adaptation value; S4: Based on the solder joint spacing adaptation value, obtain the solder joint stress transfer path, analyze the local stress condition of the solder joint, screen the area with abnormal stress change, call the solder joint strength distribution data, calculate the solder joint load difference value, identify the high stress concentration area, adjust the solder joint connection method, optimize the stress balance state of the solder joint, and obtain the solder joint stress distribution parameters; S5: Based on the stress distribution parameters of the weld points, analyze the distribution of the weld points in the overall weld structure, obtain the welding load transfer characteristics, screen the abnormal areas of the weld point topology structure, call the topology distribution adjustment factor, optimize the weld point topology density, correct the weld point arrangement, call the topology structure balance parameter, optimize the weld point distribution pattern, and obtain the weld structure optimization result.

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