Shell frame laser welding control method for camera module shell processing

Abstract

The present application relates to the field of welding control, in particular to a shell frame laser welding control method for camera module shell processing. It includes: obtaining the thermal conductivity of reference material and material parameters; calculating the welding resistance degree of the target camera module shell; calculating the laser welding urgency of each welding point of the target camera module shell in the target welding process according to the welding parameters and the welding resistance degree; obtaining the temperature reference coefficient, calculating the power setting necessity of the target welding process; obtaining the risk degree of pore proximity, calculating the power demand factor of the target welding process; obtaining the high heat presentation intensity of the target welding process, calculating the laser power demand degree of the target welding process; calculating the laser power of the target welding process. The present application can improve the welding control efficiency of camera module shell processing.

Description

Laser welding control method for camera module housing processing Technical Field

[0001] This invention relates to the field of welding control, and more specifically to a laser welding control method for a housing frame used in the processing of camera module housings. Background Technology

[0002] As a core component of the intelligent driving perception layer in automobiles, the reliability of the in-vehicle camera module greatly affects the user's driving experience. Poor sealing is a major cause of black screens and blurry images in the application of in-vehicle camera modules. Therefore, locking the upper and lower shells of the camera module during manufacturing can significantly improve driving safety.

[0003] In existing technologies, laser welding is commonly used to weld the two shells of an automotive camera module together. The principle of laser welding of automotive camera shells is based on the precise heating and melting of plastic or metal materials by laser energy. Through the thermal interaction between the materials, a firm connection of the shell components is achieved.

[0004] Traditionally, when welding the outer shell of an automotive camera module using lasers, a fixed laser emitter is used to perform laser pulse welding at the joint of the rotating upper and lower shells. The laser pulse power is usually set to a fixed value. However, in actual scenarios, the tolerance of the module shell to laser varies depending on the material and thickness. This results in low welding accuracy when using a fixed laser power value, which may lead to defects such as pores and insufficient welding in the automotive camera module shell. Summary of the Invention

[0005] This invention provides a laser welding control method for the housing frame of a camera module for processing, in order to solve existing problems.

[0006] The laser welding control method for the outer shell frame used in the processing of camera module housings of the present invention adopts the following technical solution:

[0007] One embodiment of the present invention provides a laser welding control method for a housing frame used in the processing of a camera module housing, the method comprising the following steps:

[0008] Obtain the reference material thermal conductivity of the reference camera module housing and the material parameters of the target camera module housing, wherein the material parameters include material thermal conductivity and housing thickness information;

[0009] Calculate the welding resistance of the target camera module shell based on the thermal conductivity and material parameters of the reference material;

[0010] The welding parameters of the target camera module shell in each welding process are obtained. Based on the welding parameters and welding resistance, the laser welding urgency of the target camera module shell at each welding point in the target welding process is calculated. The welding parameters include joint width information and welding distance information.

[0011] Obtain the temperature reference coefficient, and calculate the necessity of reducing the power of the target welding process based on the average value of the temperature reference coefficient and the laser welding urgency of the target camera module shell in the target welding process.

[0012] Obtain the porosity approach risk level, and calculate the power demand factor for the target welding process based on the porosity approach risk level and the necessity of power reduction;

[0013] The high heat intensity of the target welding process is obtained, and the laser power requirement of the target welding process is calculated based on the power demand factor and the high heat intensity.

[0014] Calculate the laser power required for the target welding process based on the laser power requirement of the target welding process.

[0015] Optionally, calculating the welding resistance of the target camera module housing based on the thermal conductivity and material parameters of the reference material specifically includes:

[0016] The thermal conductivity intensity factor of the target camera module shell is calculated based on the average thermal conductivity of the material and the reference material.

[0017] Based on the thermal conductivity factor and shell thickness information, the welding resistance of the target camera module shell is calculated.

[0018] Optionally, the step of calculating the laser welding urgency of each welding point of the target camera module housing during the target welding process based on welding parameters and welding resistance specifically includes:

[0019] The a-th welding process in the welding process is defined as the target welding process;

[0020] Obtain the joint width and welding distance information of the b-th welding point in the a-th welding process;

[0021] Based on the joint width and welding distance information of the b-th welding point in the a-th welding process, calculate the laser processing benefit rate of the b-th welding point in the a-th welding process;

[0022] Based on the welding resistance and the laser processing benefit rate of the b-th welding point in the a-th welding process, calculate the urgency of laser welding of the target camera module shell at the b-th welding point in the a-th welding process.

[0023] Obtain the laser welding urgency of each welding point in the a-th welding process of the target camera module shell, wherein the a-th welding process is not the first or second welding process of the target camera module shell.

[0024] Optionally, based on the joint width and welding distance information of the b-th welding point in the a-th welding process, the laser processing benefit rate of the b-th welding point in the a-th welding process is calculated, specifically including:

[0025] Take the reciprocal of the joint width information and welding distance information of the b-th welding point in the a-th welding process to obtain the joint width coefficient and welding distance coefficient respectively;

[0026] The product of the joint width coefficient and the welding distance coefficient is determined as the laser processing benefit rate.

[0027] Optionally, obtaining the temperature reference coefficient specifically includes:

[0028] Acquire historical welding data, which includes target historical welding data of the target camera module housing and reference historical welding data of the reference camera module housing. The target historical welding data includes temperature data of each welding point in each welding process of the target camera module housing, and the reference historical welding data includes temperature data of each welding point in each welding process of the reference camera module housing.

[0029] Obtain the average temperature of the (a-1)th welding process in the target historical welding data, and the average temperature of the welding process of the target reference camera module shell. The target reference camera module shell is the camera module shell with the same material parameters as the target camera module shell in the reference camera module shell. The (a-1)th welding process is not the first welding process of the target camera module shell.

[0030] The ratio of the average temperature of the (a-1)th welding process in the target historical welding data to the average temperature of the welding process of the target reference camera module shell is determined as the temperature reference coefficient.

[0031] Optionally, obtaining the stomatal proximity risk level specifically includes:

[0032] Acquire historical welding image data, which includes historical welding image data of the first welding process and historical welding image data of the second welding process. The first welding process is the welding process of the target reference camera module shell, and the welding power of the first welding process is the same as the welding power of the (a-1)th welding process.

[0033] Semantic segmentation algorithm was used to identify historical welding image data of the first welding process, and the identification results were obtained.

[0034] The welding process corresponding to the identification result is determined as the third welding process;

[0035] Calculate the sum of the number of processes in the first welding process and the number of processes in the second welding process, and subtract the number of processes in the third welding process to obtain the number of porosity processes.

[0036] The total number of processes is determined by the sum of the number of processes in the first welding process and the number of processes in the second process.

[0037] The ratio of the number of pore processes to the total number of processes is determined as the pore approach risk level.

[0038] Optionally, calculating the power demand factor for the target welding process based on the porosity proximity risk and the necessity of power reduction specifically includes:

[0039] The reciprocal of the stomatal proximity risk degree is used to obtain the stomatal proximity risk degree coefficient;

[0040] The power requirement factor for the target welding process is determined by multiplying the porosity proximity risk coefficient and the power reduction necessity.

[0041] Optionally, obtaining the high heat rendering intensity of the target welding process specifically includes:

[0042] Obtain the welding image of the (a-1)th welding process;

[0043] The Hough line detection method is used to detect the welding image of the (a-1)th welding process to obtain the detection line;

[0044] Calculate the area of ​​the molten region in the welding image of the (a-1)th welding process based on the detection line;

[0045] The Canny edge detection method is used to detect the welding image of the (a-1)th welding process to obtain the number of deep edges;

[0046] Normalize the product of the molten zone area and the number of deep edges to obtain the high heat rendering intensity of the target welding process.

[0047] Optionally, calculating the laser power requirement of the target welding process based on the power demand factor and high heat presentation intensity specifically includes:

[0048] The high heat intensity coefficient is obtained by taking the reciprocal of the high heat intensity.

[0049] The product of the power demand factor and the high thermal intensity coefficient is used to determine the laser power demand for the target welding process.

[0050] Optionally, calculating the laser power of the target welding process based on the laser power requirement of the target welding process specifically includes:

[0051] Obtain the laser power requirement and the actual laser power of the (a-1)th welding process;

[0052] Calculate the difference between the laser power demand of the target welding process and the laser power demand of the (a-1)th welding process to obtain the laser power demand difference.

[0053] The laser power demand coefficient is obtained by taking the hyperbolic tangent function of the difference in laser power demand.

[0054] The power offset is obtained by multiplying the actual laser power and the laser power demand coefficient for the (a-1)th welding process.

[0055] Calculate the sum of the actual laser power and power offset of the (a-1)th welding process to obtain the laser power of the target welding process.

[0056] The beneficial effects of the technical solution of the present invention are:

[0057] In this embodiment of the invention, the welding resistance is obtained by considering the material properties and thickness of the outer shell of the camera module. Then, the urgency of laser welding is determined by combining the joint width at the upper and lower shell splicing points and the orientation of the shell relative to the laser emission point. Furthermore, the necessity of lowering the power is determined by considering the shell temperature during welding. Simultaneously, the risk of porosity is determined by combining the actual laser beam intensity and historical porosity under the same material conditions. Based on the necessity of lowering the power and the porosity risk analysis, the laser power requirement is determined by the sufficiency of the weld coverage at the splicing point and the thermal deformation. The laser power during camera module shell welding is then negatively fed back and controlled by the real-time laser power requirement. Compared to traditional welding methods that use a preset fixed laser power value, this method can achieve a more suitable laser power control result by combining the material properties of the camera module shell and real-time operating conditions, thereby improving the welding control efficiency for camera module shell processing. Attached Figure Description

[0058] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0059] Figure 1 is a flowchart of a laser welding control method for processing a camera module housing frame according to an embodiment of the present invention. Detailed Implementation

[0060] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of the laser welding control method for processing camera module housings according to the present invention. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0061] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0062] The specific solution of the laser welding control method for the outer shell frame of the camera module shell processing provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0063] This invention provides a laser welding control method for a housing frame used in the processing of camera module housings. Referring to Figure 1, which shows a flowchart of a laser welding control method for a housing frame used in the processing of camera module housings according to an embodiment of this invention, the method includes the following steps:

[0064] S101. Obtain the reference material thermal conductivity of the reference camera module housing and the material parameters of the target camera module housing, wherein the material parameters include material thermal conductivity and housing thickness information.

[0065] For example, the tightness of the connection between the upper and lower housings of the vehicle camera module directly affects the clarity of the camera image, which in turn affects the driver's driving experience. If the welding tightness of the camera module housing in the welding process is poor, the internal circuit board will be affected by the air blown in, which will reduce the image quality and thus increase the driving risk.

[0066] Currently, laser welding technology is commonly used to weld the upper and lower shells of the camera module. The high-temperature laser melts the material at the joint, thus making the shells tightly connected.

[0067] When performing laser welding on the housing of an in-vehicle camera module, the upper and lower housings are pre-assembled and fixed to the operating table. During welding, the laser emitter is fixed, while the housing clamping device drives the housing to rotate at a certain angular velocity at a constant speed. This allows the laser to fully act on the splicing parts of the upper and lower housings of the camera module, achieving a tight weld. In contrast, traditional laser welding often uses a constant laser power, which makes this welding method less adaptable to the welding of camera module housings.

[0068] Therefore, based on the above issues, all already welded camera module housings can be obtained, denoted as reference camera module housings, and their material thermal conductivity can be obtained, denoted as reference material thermal conductivity. The target camera module housing can be a camera module housing that is already in the welding process, or a camera module housing that is about to undergo the welding process.

[0069] S102. Calculate the welding resistance of the target camera module shell based on the thermal conductivity and material parameters of the reference material.

[0070] In this embodiment, the welding resistance of the target camera module shell is calculated based on the thermal conductivity and material parameters of the reference material, specifically including:

[0071] The thermal conductivity intensity factor of the target camera module shell is calculated based on the average thermal conductivity of the material and the reference material.

[0072] Based on the thermal conductivity factor and shell thickness information, the welding resistance of the target camera module shell is calculated.

[0073] For example, considering the different thermal conductivity and thickness of the materials of different camera module housings, they exhibit different resistance to lasers. Lasers have a stronger melting effect on housing materials with low thickness and high thermal conductivity. Therefore, the welding resistance of the welding point in real time is first obtained based on the housing characteristics.

[0074] First, the materials used for the housings of different vehicle camera modules vary due to their performance characteristics, applicable scenarios, and costs. For example, aluminum alloys are lightweight, have high thermal conductivity, good mechanical strength, and are easy to process, while copper and copper alloys have excellent electromagnetic shielding effects but are expensive. Different housing materials have different thermal conductivity, and the difference in thermal conductivity results in differences in the heat resistance of the housing material to the laser during laser welding.

[0075] Therefore, calculating the thermal conductivity intensity factor of the target camera module shell based on the average thermal conductivity of the material and the reference material can specifically include: subtracting the average thermal conductivity of the reference material from the thermal conductivity of the material, and normalizing the difference to obtain the thermal conductivity intensity factor of the target camera module shell.

[0076] The thermal conductivity intensity factor of the target camera module shell is calculated based on the average thermal conductivity of the material and the reference material. The formula used is as follows:

[0077]

[0078] in, Indicates the thermal conductivity of the material. This represents the average thermal conductivity of the reference material. Represents the normalization function. This represents the thermal conductivity intensity factor of the target camera module shell. In the formula, a higher thermal conductivity of the target camera module shell material compared to other materials indicates that the target camera module shell is more easily melted under the same laser power.

[0079] Furthermore, due to the influence of applicable scenarios and production processes, the shell thickness of different vehicle camera modules varies. For thicker shells, higher laser power should be applied to help the material weld and melt.

[0080] Therefore, calculating the welding resistance of the target camera module shell based on the thermal conductivity intensity factor and shell thickness information can specifically include: taking the reciprocal of the thermal conductivity intensity factor to obtain the thermal conductivity intensity factor coefficient; and multiplying the thermal conductivity intensity factor coefficient and the shell thickness information to obtain the welding resistance of the target camera module shell.

[0081] The calculation formula used can be:

[0082]

[0083] in, Indicates welding resistance. This indicates the shell thickness information. In the formula, if the thickness of the target camera module shell is greater and the thermal conductivity factor of the shell material is smaller, it means that the laser beam has stronger penetration resistance to the target camera module shell, and therefore a higher laser power is required for melting and welding the shell material during laser welding.

[0084] S103. Obtain the welding parameters of the target camera module shell in each welding process, and calculate the laser welding urgency of each welding point of the target camera module shell in the target welding process based on the welding parameters and welding resistance. The welding parameters include joint width information and welding distance information.

[0085] In this embodiment, the urgency of laser welding at each welding point of the target camera module shell during the target welding process is calculated based on welding parameters and welding resistance. Specifically, this includes:

[0086] The a-th welding process in the welding process is defined as the target welding process;

[0087] Obtain the joint width and welding distance information of the b-th welding point in the a-th welding process;

[0088] Based on the joint width and welding distance information of the b-th welding point in the a-th welding process, calculate the laser processing benefit rate of the b-th welding point in the a-th welding process;

[0089] Based on the welding resistance and the laser processing benefit rate of the b-th welding point in the a-th welding process, calculate the urgency of laser welding of the target camera module shell at the b-th welding point in the a-th welding process.

[0090] Obtain the laser welding urgency of each welding point in the a-th welding process of the target camera module shell, wherein the a-th welding process is not the first or second welding process of the target camera module shell.

[0091] For example, in this embodiment, the welding process of the target camera module housing is divided into multiple welding processes. In a preferred embodiment, the duration of each welding process is 0.5 seconds. The duration of each welding process can be set according to actual conditions and is not specifically limited here. Each welding process may include multiple welding points, and the laser power remains constant within a single welding process.

[0092] During the laser welding process, the upper and lower shells of the camera module housing need to be pre-assembled and aligned to form a seam. Due to the influence of casting process precision, the seam width varies at different welding points on the camera module housing. For welding points with wider seams, higher laser power should be applied to form a sufficient molten area to cover the seam between the upper and lower shells and increase airtightness.

[0093] Furthermore, during the laser welding process, the module shell is carried by the clamping device and rotates at a constant speed. When the distance between the real-time welding point and the laser emitting head is closer, the laser energy attenuation is less. That is, if the joint width at the welding point is smaller and closer to the laser emitting head, the benefit rate of the laser to the welding point is higher and the welding effect is more complete.

[0094] Therefore, during the welding process of the target camera module housing, in the a-th welding process, the joint width information of the upper and lower housings at each welding point is obtained. Information on the welding distance between each welding point and the laser emitter. The a-th welding process can be considered either the process about to begin welding or the current welding process.

[0095] Based on the joint width and welding distance information of the b-th welding point in the a-th welding process, the laser processing benefit rate of the b-th welding point in the a-th welding process can be calculated, which can specifically include:

[0096] Take the reciprocal of the joint width information and welding distance information of the b-th welding point in the a-th welding process to obtain the joint width coefficient and welding distance coefficient respectively. The product of the joint width coefficient and welding distance coefficient is determined as the laser processing benefit rate.

[0097] Based on the joint width and welding distance information of the b-th welding point in the a-th welding process, the laser processing benefit rate of the b-th welding point in the a-th welding process can be calculated using the following formula:

[0098]

[0099] in, This indicates the benefit rate of laser processing.

[0100] In the formula, if the width of the joint between the upper and lower shells is small at the a-th welding process during the welding of the target camera module shell, then only a small amount of material needs to be melted by a low-power laser to meet the airtightness requirement. At the same time, if the distance between the laser emitter and the welding point is closer, the laser attenuation will be less, which further indicates that the laser has a more sufficient effect on the welding point, that is, the laser processing benefit rate is higher.

[0101] Based on the welding resistance and the laser processing benefit rate at the b-th welding point in the a-th welding process, the urgency of laser welding of the target camera module shell at the b-th welding point in the a-th welding process is calculated, specifically including:

[0102] The laser processing benefit rate coefficient of the b-th welding point in the a-th welding process is obtained by taking the reciprocal of the laser processing benefit rate of the b-th welding point in the a-th welding process.

[0103] The product of the laser processing benefit rate coefficient and the welding resistance at the b-th welding point in the a-th welding process is normalized, and the normalized result is determined as the laser welding urgency at the b-th welding point in the a-th welding process.

[0104] Based on the welding resistance and the laser processing benefit rate at the b-th welding point in the a-th welding process, the urgency of laser welding of the target camera module shell at the b-th welding point in the a-th welding process is calculated using the following formula:

[0105]

[0106] in, Indicates the urgency of laser welding. This represents the normalization function.

[0107] S104. Obtain the temperature reference coefficient. Based on the temperature reference coefficient and the average value of the laser welding urgency of the target camera module shell in the target welding process, calculate the necessity of power reduction in the target welding process.

[0108] In this embodiment, obtaining the temperature reference coefficient specifically includes:

[0109] Acquire historical welding data, which includes target historical welding data of the target camera module housing and reference historical welding data of the reference camera module housing. The target historical welding data includes temperature data of each welding point in each welding process of the target camera module housing, and the reference historical welding data includes temperature data of each welding point in each welding process of the reference camera module housing.

[0110] Obtain the average temperature of the (a-1)th welding process in the target historical welding data, and the average temperature of the welding process of the target reference camera module shell. The target reference camera module shell is the camera module shell with the same material parameters as the target camera module shell in the reference camera module shell. The (a-1)th welding process is not the first welding process of the target camera module shell.

[0111] The ratio of the average temperature of the (a-1)th welding process in the target historical welding data to the average temperature of the welding process of the target reference camera module shell is determined as the temperature reference coefficient.

[0112] For example, excessively high laser power may affect the performance of electronic components inside the camera module housing. Therefore, it is necessary to maintain the welding temperature within a reasonable range during the welding process. The temperature generated by the laser beam acting on the housing is mainly related to the housing material. That is, the heat generated by the same laser power acting on different positions of the same module housing can be approximated as the same. Therefore, the temperature value of each welding point in the (a-1)th welding process in the historical welding data is obtained and averaged to obtain the average temperature of the (a-1)th welding process. Furthermore, it acquires the target camera module shell with the same material parameters as the target camera module shell from historical welding processes, thus obtaining the target reference camera module shell. It then calculates the average temperature at each welding point throughout all welding processes of each target reference camera module shell, obtaining the average temperature of the welding process for the target reference camera module shell. .

[0113] Calculate the average temperature of the (a-1)th welding process. Average temperature of the welding process of the target reference camera module housing The ratio of these values ​​is used to obtain the temperature reference coefficient.

[0114] The average laser welding urgency of the target camera module shell in the a-th welding process is obtained by averaging the laser welding urgency of each welding point.

[0115] Based on the temperature reference coefficient and the average value of the laser welding urgency of the target camera module shell during the target welding process, the necessity of reducing the power of the target welding process is calculated, specifically including:

[0116] The laser welding urgency coefficient for the a-th welding process is obtained by taking the reciprocal of the mean value of the laser welding urgency for the a-th welding process.

[0117] The product of the laser welding urgency coefficient and the temperature reference coefficient for the a-th welding process is determined as the power reduction necessity for the target welding process.

[0118] Based on the temperature reference coefficient and the average laser welding urgency of the target camera module housing during the target welding process, the necessity of reducing the power in the target welding process is calculated. The calculation formula used is as follows:

[0119]

[0120] in, This indicates the necessity of reducing the power for the target welding process. This represents the average urgency of laser welding in the a-th welding process.

[0121] In the formula, if the temperature in the previous welding process (i.e., the (a-1)th welding process) is higher than the temperature level of the welding process with the same shell material and thickness in history, it reflects that the temperature of the previous welding process is more likely to be too high. This reflects that the laser power of the target welding process needs to be reduced compared to the previous process. Furthermore, the lower the urgency level of laser welding at each welding point in the target welding process, the higher the necessity of reducing the laser power of the target welding process compared to the previous process.

[0122] S105. Obtain the porosity approach risk level, and calculate the power demand factor for the target welding process based on the porosity approach risk level and the necessity of power reduction.

[0123] In this embodiment, obtaining the stomatal proximity risk level specifically includes:

[0124] Acquire historical welding image data, which includes historical welding image data of the first welding process and historical welding image data of the second welding process. The first welding process is the welding process of the target reference camera module shell, and the welding power of the first welding process is the same as the welding power of the (a-1)th welding process.

[0125] Semantic segmentation algorithm was used to identify historical welding image data of the first welding process, and the identification results were obtained.

[0126] The welding process corresponding to the identification result is determined as the third welding process;

[0127] Calculate the sum of the number of processes in the first welding process and the number of processes in the second welding process, and subtract the number of processes in the third welding process to obtain the number of porosity processes.

[0128] The total number of processes is determined by the sum of the number of processes in the first welding process and the number of processes in the second process.

[0129] The ratio of the number of pore processes to the total number of processes is determined as the pore approach risk level.

[0130] Based on the risk level of porosity approach and the necessity of power reduction, the power demand factor for the target welding process is calculated, specifically including:

[0131] The reciprocal of the stomatal proximity risk degree is used to obtain the stomatal proximity risk degree coefficient;

[0132] The power requirement factor for the target welding process is determined by multiplying the porosity proximity risk coefficient and the power reduction necessity.

[0133] For example, excessively high laser power may cause the weld to burn through due to excessive heat accumulation, resulting in porosity. Using a semantic segmentation algorithm to identify historical welding image data from the first welding process yields images that do not contain porosity.

[0134] Historical welding image data is acquired, and welding images of camera module shells with the same material parameters as the target camera module shell and the same welding power as the (a-1)th welding process are identified from the historical welding image data (i.e., historical welding image data of the first welding process). Welding images excluding porosity are identified using a semantic segmentation algorithm. The ratio of the number of processes exhibiting porosity (i.e., the number of third welding processes) to the total number of welding processes is then calculated and denoted as the porosity approach risk level. The larger this value, the greater the possibility that the laser power will cause porosity in the (a-1)th welding process. This indicates that the laser power value in the (a-1)th welding process is too high, and the laser power needs to be further reduced in the (a)th welding process.

[0135] Based on the risk of porosity approach and the necessity of power reduction, the power demand factor for the target welding process is calculated using the following formula:

[0136]

[0137] in, This represents the power demand factor.

[0138] S106. Obtain the high heat intensity of the target welding process, and calculate the laser power requirement of the target welding process based on the power requirement factor and the high heat intensity.

[0139] In this embodiment, obtaining the high heat rendering intensity of the target welding process specifically includes:

[0140] Obtain the welding image of the (a-1)th welding process;

[0141] The Hough line detection method is used to detect the welding image of the (a-1)th welding process to obtain the detection line;

[0142] Calculate the area of ​​the molten region in the welding image of the (a-1)th welding process based on the detection line;

[0143] The Canny edge detection method is used to detect the welding image of the (a-1)th welding process to obtain the number of deep edges;

[0144] Normalize the product of the molten zone area and the number of deep edges to obtain the high heat rendering intensity of the target welding process.

[0145] Based on the power demand factor and high heat presentation intensity, the laser power demand of the target welding process is calculated, specifically including:

[0146] The high heat intensity coefficient is obtained by taking the reciprocal of the high heat intensity.

[0147] The product of the power demand factor and the high thermal intensity coefficient is used to determine the laser power demand for the target welding process.

[0148] For example, when the laser power is too high, the area covered by the molten material will be too large, resulting in a thin shell material, which makes it difficult to guarantee the airtightness between the upper and lower shells of the camera module.

[0149] Therefore, the welding image of the (a-1)th welding process is obtained, and the image is processed using the Hough line detection technique to extract the straight lines on both sides of the molten area, thereby locating the area of ​​the molten area, i.e., the welding coverage area. The welding coverage area of ​​the previous welding process is denoted as... Furthermore, if the laser power is too high in the (a-1)th welding process, the redundant high heat may cause thermal deformation within the welding area, making the molten area uneven and rugged after cooling. This is reflected in the image as an increase in deep edges. Therefore, Canny edge detection is performed on the welding coverage area within the welding image of the (a-1)th welding process to obtain the number of detected deep edges. .

[0150] The formula for calculating the intensity of high heat presentation can be:

[0151]

[0152] in, This indicates the intensity of high heat. In the formula, the larger the welding coverage area of ​​the welding region corresponding to the (a-1)th welding process, and the stronger the deep texture performance within the coverage area, the more intense the high heat performance caused by the actual laser power on the shell in the (a-1)th welding process is.

[0153] Next, if the target camera module housing corresponds to the power demand factor during the target welding process... The larger the volume, the stronger the heat. The smaller the value, the greater the actual laser power requirement of the target welding process compared to the (a-1)th welding process. Therefore, the formula for calculating the laser power requirement can be:

[0154]

[0155] in, This indicates the laser power requirement.

[0156] S107. Calculate the laser power of the target welding process based on the laser power requirement of the target welding process.

[0157] In this embodiment, the laser power of the target welding process is calculated based on the laser power requirement of the target welding process, specifically including:

[0158] Obtain the laser power requirement and the actual laser power of the (a-1)th welding process;

[0159] Calculate the difference between the laser power demand of the target welding process and the laser power demand of the (a-1)th welding process to obtain the laser power demand difference.

[0160] The laser power demand coefficient is obtained by taking the hyperbolic tangent function of the difference in laser power demand.

[0161] The power offset is obtained by multiplying the actual laser power and the laser power demand coefficient for the (a-1)th welding process.

[0162] Calculate the sum of the actual laser power and power offset of the (a-1)th welding process to obtain the laser power of the target welding process.

[0163] For example, the formula for calculating the laser power of the target welding process can be:

[0164]

[0165] in, The laser power indicating the target welding process, This represents the laser power in the (a-1)th welding process. This represents the laser power requirement for the (a-1)th welding process. This indicates the difference in laser power demand. This represents the laser power demand coefficient. This indicates the power offset.

[0166] After obtaining the laser power of the target welding process, the target welding process is laser-melted using that power. Each subsequent process is then treated as a target welding process, and the laser power for each process is calculated to weld the target camera module housing. During laser welding, a protective gas is simultaneously applied to the welding position. Argon (Ar) or a helium-argon mixture (He+Ar) is commonly used in laser welding of metal camera modules. Once all welding positions on the current camera module housing have been processed, the laser input is stopped. A trimming machine is used to remove welding excess material (such as burrs and flash) to ensure a smooth appearance. The weld seams are then sanded with sandpaper (400-600 grit) to remove oxide scale and slag. Finally, a polishing machine (or chemical polishing) is used to smooth the surface of the target camera module housing, resulting in a welded camera module housing.

[0167] In summary, in this embodiment of the invention, the welding resistance is obtained by considering the material characteristics and thickness of the outer shell of the camera module. Then, the urgency of laser welding is determined by combining the joint width at the upper and lower shell splicing points and the orientation of the shell relative to the laser emission point. Furthermore, the necessity of reducing the power is determined by considering the shell temperature during welding. Simultaneously, the real-time risk of porosity is determined by combining the actual laser beam intensity and historical porosity under the same material conditions. Based on the necessity of reducing the power and the porosity risk analysis, the laser power requirement is determined by the sufficiency of the weld coverage at the splicing point and the thermal deformation. Finally, the laser power is negatively fed back and controlled during camera module shell welding based on the real-time laser power requirement. Compared to traditional welding methods that use a preset fixed laser power value, this method can achieve a more suitable laser power control result by combining the material characteristics of the camera module shell and the real-time operating conditions, thereby improving the welding control efficiency for camera module shell processing.

[0168] It should be noted that the order of the above embodiments of the present invention is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. The processes depicted in the accompanying drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0169] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0170] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A laser welding control method for a housing frame used in the processing of a camera module housing, characterized in that, include: The process involves: acquiring the reference material thermal conductivity of the reference camera module housing and the material parameters of the target camera module housing, including material thermal conductivity and housing thickness information; calculating the welding resistance of the target camera module housing based on the reference material thermal conductivity and material parameters; acquiring the welding parameters of the target camera module housing in each welding process; calculating the laser welding urgency of the target camera module housing at each welding point in the target welding process based on the welding parameters and welding resistance, where the welding parameters include joint width information and welding distance information; specifically, calculating the laser welding urgency of the target camera module housing at each welding point in the target welding process based on the welding parameters and welding resistance includes: determining the a-th welding process as the target welding process; acquiring the joint width information and welding distance information of the b-th welding point in the a-th welding process; and calculating the laser welding urgency of the b-th welding point in the a-th welding process based on the joint width information and welding distance information of the b-th welding point in the a-th welding process. The laser processing benefit rate at each welding point is calculated. Based on the welding resistance and the laser processing benefit rate at the b-th welding point in the a-th welding process, the urgency of laser welding for the target camera module housing at the b-th welding point in the a-th welding process is calculated. The urgency of laser welding for each welding point of the target camera module housing in the a-th welding process is obtained, where the a-th welding process is not the first or second welding process of the target camera module housing. The temperature reference coefficient is obtained, and the necessity of power reduction for the target welding process is calculated based on the temperature reference coefficient and the average value of the laser welding urgency of the target camera module housing in the target welding process. The porosity approach risk is obtained, and the power demand factor for the target welding process is calculated based on the porosity approach risk and the necessity of power reduction. The high heat presentation intensity of the target welding process is obtained, and the laser power demand for the target welding process is calculated based on the power demand factor and the high heat presentation intensity. The laser power demand for the target welding process is calculated based on the laser power demand for the target welding process.

2. The laser welding control method for the shell frame of a camera module shell processing according to claim 1, characterized in that, The step of calculating the welding resistance of the target camera module shell based on the thermal conductivity of the reference material and material parameters specifically includes: calculating the thermal conductivity intensity factor of the target camera module shell based on the average thermal conductivity of the material and the reference material; and calculating the welding resistance of the target camera module shell based on the thermal conductivity intensity factor and shell thickness information.

3. The laser welding control method for the shell frame of a camera module shell processing according to claim 1, characterized in that, The step of calculating the laser processing benefit rate of the b-th welding point in the a-th welding process based on the joint width information and welding distance information of the b-th welding point in the a-th welding process specifically includes: taking the reciprocal of the joint width information and welding distance information of the b-th welding point in the a-th welding process to obtain the joint width coefficient and welding distance coefficient respectively; and determining the laser processing benefit rate by multiplying the joint width coefficient and welding distance coefficient.

4. The laser welding control method for the shell frame of a camera module shell processing according to claim 1, characterized in that, The acquisition of the temperature reference coefficient specifically includes: acquiring historical welding data, which includes target historical welding data of the target camera module shell and reference historical welding data of the reference camera module shell. The target historical welding data includes temperature data of each welding point in each welding process of the target camera module shell, and the reference historical welding data includes temperature data of each welding point in each welding process of the reference camera module shell; acquiring the average temperature of the (a-1)th welding process in the target historical welding data and the average temperature of the welding process of the target reference camera module shell, wherein the target reference camera module shell is the camera module shell with the same material parameters as the target camera module shell, and the (a-1)th welding process is not the first welding process of the target camera module shell; and determining the ratio of the average temperature of the (a-1)th welding process in the target historical welding data to the average temperature of the welding process of the target reference camera module shell as the temperature reference coefficient.

5. The laser welding control method for the shell frame of a camera module shell processing according to claim 1, characterized in that, The method for obtaining the porosity approach risk level specifically includes: acquiring historical welding image data, wherein the historical welding image data includes historical welding image data of a first welding process and historical welding image data of a second welding process, the first welding process being the welding process of the target reference camera module shell, and the welding power of the first welding process being the same as the welding power of the (a-1)th welding process; using a semantic segmentation algorithm to identify the historical welding image data of the first welding process to obtain the identification result; determining the welding process corresponding to the identification result as the third welding process; calculating the sum of the number of processes of the first welding process and the number of processes of the second welding process, and subtracting the number of processes of the third welding process to obtain the number of porosity processes; determining the total number of processes as the sum of the number of processes of the first welding process and the number of processes of the second welding process; and determining the ratio of the number of porosity processes to the total number of processes as the porosity approach risk level.

6. The laser welding control method for the shell frame of a camera module shell processing according to claim 1, characterized in that, The calculation of the power demand factor for the target welding process based on the porosity approach risk degree and the necessity of power reduction specifically includes: taking the reciprocal of the porosity approach risk degree to obtain the porosity approach risk degree coefficient; and determining the power demand factor for the target welding process by multiplying the porosity approach risk degree coefficient and the necessity of power reduction.

7. The laser welding control method for the shell frame of a camera module shell processing according to claim 1, characterized in that, The process of obtaining the high heat rendering intensity of the target welding process specifically includes: acquiring the welding image of the (a-1)th welding process; using the Hough line detection method to detect the welding image of the (a-1)th welding process and obtaining a detection line; calculating the area of ​​the molten region in the welding image of the (a-1)th welding process based on the detection line; using the Canny edge detection method to detect the welding image of the (a-1)th welding process and obtaining the number of deep edges; and normalizing the product of the molten region area and the number of deep edges to obtain the high heat rendering intensity of the target welding process.

8. The laser welding control method for the shell frame of a camera module shell processing according to claim 1, characterized in that, The step of calculating the laser power requirement of the target welding process based on the power requirement factor and the high heat presentation intensity specifically includes: taking the reciprocal of the high heat presentation intensity to obtain the high heat presentation intensity coefficient; and determining the laser power requirement of the target welding process by multiplying the power requirement factor and the high heat presentation intensity coefficient.

9. The laser welding control method for the housing frame of a camera module housing according to claim 1, characterized in that, The step of calculating the laser power of the target welding process based on the laser power requirement of the target welding process specifically includes: obtaining the laser power requirement of the (a-1)th welding process and the actual laser power of the (a-1)th welding process; calculating the difference between the laser power requirement of the target welding process and the laser power requirement of the (a-1)th welding process to obtain the laser power requirement difference; taking the hyperbolic tangent function on the laser power requirement difference to obtain the laser power requirement coefficient; calculating the product of the actual laser power of the (a-1)th welding process and the laser power requirement coefficient to obtain the power offset; and calculating the sum of the actual laser power of the (a-1)th welding process and the power offset to obtain the laser power of the target welding process.

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