Welding method and welding system

Abstract

The embodiment of the invention provides a welding method and a welding system. The method comprises the steps that a heat dissipation bonding pad is drawn based on bonding pad layout parameters so that the heat dissipation bonding pad composed of a plurality of sub bonding pads can be printed on a circuit board of the data transmission module, the bonding pad layout parameters at least comprise shape parameters and size parameters, and the interval between every two adjacent sub bonding pads in the multiple sub bonding pads is larger than a preset interval; a printing steel mesh corresponding to the heat dissipation bonding pad is manufactured based on steel mesh design parameters, the steel mesh design parameters at least comprise shape parameters and size parameters, the shape parameters in the steel mesh design parameters are the same as the shape parameters in the bonding pad layout parameters, and the size parameters in the steel mesh design parameters are the same as the size parameters in the bonding pad layout parameters; before the reflow soldering stage, a welding agent is printed on the heat dissipation bonding pad through the printing steel mesh, and welding of the data transmission module is achieved. In this way, the voidage after welding is reduced, and the influence on the use performance of the vehicle machine and the use experience of a user is avoided.

Description

Technical Field

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

[0002] With the development trend of intelligent automobiles, data transmission modules in smart vehicles (such as 4G&BT / Wi-Fi modules) are becoming increasingly important. The 4G&BT / Wi-Fi module integrates functions such as 4G, Bluetooth and Wi-Fi, and provides support for communication between vehicles and base stations, gateways, cloud devices and other devices.

[0003] In the related technology, since the GND PAD (heat dissipation pad) of the 4G & BT / Wi-Fi modules are all covered with copper, the solder paste coverage rate (the percentage of solder paste covering the heat dissipation pad) on the heat dissipation pad is relatively large during the welding process, which makes it more difficult to weld the module during SMT (Surface Mount Technology), resulting in a high bubble void rate caused by welding, which seriously affects the performance of the vehicle computer and the user experience. Summary of the invention

[0004] In view of this, the embodiments of the present application provide a welding method and a welding system to solve or alleviate the problem in the related art that the bubble void rate is high due to welding, which seriously affects the performance of the vehicle computer and the user experience.

[0005] According to a first aspect of an embodiment of the present application, a welding method is provided, the method comprising: drawing a heat dissipation pad based on a pad layout parameter so as to print the heat dissipation pad composed of a plurality of sub-pads on a circuit board of a data transmission module, the pad layout parameter comprising at least a shape parameter and a size parameter, and a spacing between two adjacent sub-pads among the plurality of sub-pads is greater than a preset spacing; based on a steel mesh design parameter, producing a printed steel mesh corresponding to the heat dissipation pad, the steel mesh design parameter comprising at least a shape parameter and a size parameter, the shape parameter in the steel mesh design parameter being the same as the shape parameter in the pad layout parameter, and the size parameter in the steel mesh design parameter being the same as the size parameter in the pad layout parameter; before the reflow soldering stage, printing solder onto the heat dissipation pad through the printed steel mesh to achieve welding of the data transmission module.

[0006] In some embodiments of the present application, a heat dissipation pad is drawn based on the pad layout parameters, including: drawing a square matrix in the area to which the heat dissipation pad belongs based on the shape parameters in the pad layout parameters; dividing the square matrix into a plurality of square blocks with equal intervals, and drawing a heat dissipation pad composed of a plurality of sub-pads in the area corresponding to the square blocks, wherein each of the plurality of sub-pads has the same shape.

[0007] In some embodiments of the present application, drawing the heat dissipation pad based on the pad layout parameters further includes: adjusting the size of each sub-pad to the same value based on the size parameter in the pad layout parameters.

[0008] In some embodiments of the present application, a printed steel mesh corresponding to the heat dissipation pad is manufactured based on the steel mesh design parameters, including: based on the shape parameters in the steel mesh design parameters, cutting multiple printed holes of the same shape as multiple sub-pads on the area of ​​the printed steel mesh to be cut corresponding to the heat dissipation pad to obtain the printed steel mesh, wherein the number of printed holes in the printed steel mesh is the same as the number of sub-pads.

[0009] In some embodiments of the present application, a printed steel mesh corresponding to the heat dissipation pad is produced based on the steel mesh design parameters, and also includes: based on the size parameters in the steel mesh design parameters, the size of each printed hole is adjusted to the same parameters, and the size of each printed hole is the same as the size of each sub-pad.

[0010] In some embodiments of the present application, the welding method also includes: adjusting the thickness of the steel mesh in the area corresponding to the printed steel mesh and the heat dissipation pad from the initial thickness to the target thickness; when printing solder onto the heat dissipation pad through the printed steel mesh, controlling the volume of the solder accommodated in the printing holes of the printed steel mesh to reach the target volume.

[0011] In some embodiments of the present application, the soldering method further includes: before the reflow soldering stage, printing solder onto a heat dissipation pad printed on a circuit board through a printed steel mesh so that the solder is distributed on each sub-pad of the heat dissipation pad.

[0012] In some embodiments of the present application, the soldering method further includes: in the reflow soldering stage, placing the circuit board at a liquefaction temperature of the solder.

[0013] In some embodiments of the present application, the welding method also includes: obtaining the solder liquefaction time of the reflow soldering stage; determining the solder liquefaction time of the heat absorption zone and the solder liquefaction time of the reflow soldering zone in the solder liquefaction time; liquefying the solder according to the solder liquefaction time of the heat absorption zone and the solder liquefaction time of the reflow soldering zone.

[0014] According to a second aspect of an embodiment of the present application, a welding system is provided, the system comprising: a drawing device, for drawing a heat dissipation pad based on a pad layout parameter so that a heat dissipation pad composed of a plurality of sub-pads can be printed on a circuit board of a data transmission module, the pad layout parameter comprising at least a shape parameter and a size parameter, and a spacing between two adjacent sub-pads among the plurality of sub-pads is greater than a preset spacing; a steel mesh production device, for producing a printed steel mesh corresponding to the heat dissipation pad based on a steel mesh design parameter, the steel mesh design parameter comprising at least a shape parameter and a size parameter, the shape parameter in the steel mesh design parameter being the same as the shape parameter in the pad layout parameter, and the size parameter in the steel mesh design parameter being the same as the size parameter in the pad layout parameter; a welding device, for printing welding agent onto the heat dissipation pad by means of a printed steel mesh before a reflow soldering stage, so as to achieve welding of the data transmission module.

[0015] According to the welding method and welding system provided in the embodiment of the present application, a heat dissipation pad is drawn based on the pad layout parameters, and a printed steel mesh corresponding to the heat dissipation pad is manufactured based on the steel mesh design parameters. Before the reflow soldering stage, the solder paste can be printed on the heat dissipation pad composed of a plurality of sub-pads through the printed steel mesh, so that the solder paste is evenly distributed on each sub-pad to realize the welding of the data transmission module. Moreover, since there is a certain interval between two adjacent sub-pads, the solder paste can diffuse to the interval between the two adjacent sub-pads, thereby reducing the void rate after welding and avoiding affecting the performance of the vehicle computer and the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0017] Figure 1 is a schematic flow chart of a welding method according to an embodiment of the present application;

[0018] Figure 2 It is a schematic diagram of a heat dissipation pad of a data transmission module in the related art;

[0019] Figure 3 It is a schematic diagram of the heat dissipation pad of the data transmission module after welding in the related art;

[0020] Figure 4 is a schematic diagram of a heat dissipation pad according to an embodiment of the present application;

[0021] Figure 5 is a schematic diagram of a printing steel mesh according to an embodiment of the present application;

[0022] Figure 6 The figure is a structural block diagram of a welding system according to one embodiment of the present application. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the embodiments of the present application should fall within the scope of protection of the embodiments of the present application.

[0024] The specific implementation of the embodiments of the present application is further explained below in combination with the embodiments of the present application and the accompanying drawings.

[0025] Figure 1 The figure is a schematic flow chart of a welding method according to an embodiment of the present application.

[0026] like Figure 1 As shown, the welding method includes:

[0027] S11: Drawing a heat dissipation pad based on pad layout parameters so as to print the heat dissipation pad composed of multiple sub-pads on a circuit board of a data transmission module, wherein the pad layout parameters include at least a shape parameter and a size parameter, and a spacing between two adjacent sub-pads among the multiple sub-pads is greater than a preset spacing.

[0028] Specifically, the data transmission module refers to the 4G&BT / Wi-Fi module, which integrates 4G, Bluetooth and Wi-Fi functions, and provides support for communication between the vehicle and base stations, gateways, cloud devices and other devices. The heat dissipation pad refers to the GND PAD of the 4G&BT / Wi-Fi module. The preset interval can be 0 or other parameters close to 0.

[0029] For example, Figure 2 is a schematic diagram of a heat dissipation pad of a data transmission module in the related art, Figure 3 This is a schematic diagram of the heat dissipation pad of the data transmission module after welding in the related art.

[0030] like Figure 2 As shown, the heat dissipation pad GND PAD is designed as a whole piece, which increases the copper covering area and is conducive to the rapid conduction and diffusion of the heat generated by the module.

[0031] However, during SMT reflow soldering, due to Figure 2The GND PAD in the figure is designed as a whole piece. Therefore, after the solder (such as solder paste) on the GND PAD melts, the solder paste absorbs more and more energy from the outside world during the heating (liquid to solid) process, and the solder paste tension becomes greater and greater. Therefore, the solder paste (liquid) will gather in one direction, and gradually form a situation where there is no solder paste coverage in some parts, forming the following on the surface of the GND PAD: Figure 3 The bubbles shown in the figure lead to a large void rate after welding (the void rate refers to the proportion of bubbles or areas without solder paste in the solder joint, usually the void rate is ≥70%), which directly affects the reliability and heat dissipation of the 4G&BT / Wi-Fi module, thereby seriously affecting the function of the car machine and the user's driving experience (for example, due to poor heat dissipation during navigation, the navigation system freezes or has no signal, causing the user to take the wrong road or lose the destination. In severe cases, the car will be destroyed and people will die).

[0032] Therefore, in order to reduce the void rate after SMT soldering, a heat dissipation pad is drawn based on pad layout parameters on a drawing device installed with drawing tools (such as AltiumDesigner, Mentor Pads, Cadence Allegro and other tools for drawing PCB boards) so that a heat dissipation pad composed of multiple sub-pads can be printed on the circuit board of the data transmission module. The pad layout parameters include at least shape parameters and size parameters, and the interval between two adjacent sub-pads among the multiple sub-pads is greater than the preset interval.

[0033] For example, Figure 4 is a schematic diagram of a heat dissipation pad according to an embodiment of the present application, such as Figure 4 As shown, a whole GND PAD is adjusted to a heat dissipation pad with a 36-grid layout consisting of multiple sub-pads. The number, shape, size and other parameters of the sub-pads can be Figure 4 As shown, other parameters may also be used, and this application does not limit them here.

[0034] It can be understood that when the GND PAD is adjusted as Figure 4 After the structure shown, during SMT welding, after the solder (such as solder paste) of each sub-pad on the GND PAD melts, since there is a certain gap between two adjacent sub-pads, the solder paste can diffuse to the gap between the two adjacent sub-pads, so that the solder paste is evenly distributed on each sub-pad, avoiding the situation where there is no local coverage of solder paste, thereby reducing the void rate after SMT welding and avoiding affecting the performance of the vehicle computer and the user experience.

[0035] S12: Based on the steel mesh design parameters, a printed steel mesh corresponding to the heat dissipation pad is manufactured, the steel mesh design parameters include at least shape parameters and size parameters, the shape parameters in the steel mesh design parameters are the same as the shape parameters in the pad layout parameters, and the size parameters in the steel mesh design parameters are the same as the size parameters in the pad layout parameters.

[0036] Among them, during the reflow soldering process, the printed steel mesh will cover the solder layer, and then the solder will be accurately printed on the heat sink pad area of ​​the PCB through the printed holes on the steel mesh, so as to achieve accurate soldering in the subsequent component mounting process. Therefore, after the heat sink pad is adjusted from a whole block layout to a 36-grid layout, the layout of the printed steel mesh used to print solder on the heat sink pad also needs to be adjusted accordingly.

[0037] For example, Figure 5 is a schematic diagram of a printed steel mesh according to an embodiment of the present application, such as Figure 5 As shown, a printed stencil corresponding to the heat sink pad is produced by a stencil production device based on stencil design parameters, and the area corresponding to the heat sink pad is also a 36-grid layout. When the layout of the heat sink pad is adjusted from a 36-grid form to another form, the area corresponding to the heat sink pad in the printed stencil should also be adjusted from a 36-grid form to another form.

[0038] It should be noted that when the printing steel mesh is made by the steel mesh making equipment, it can be made by chemical etching, electroforming or laser cutting. Among them, the chemical etching method is to lay a layer of acid-proof glue on the printing steel mesh, and then clean the acid-proof glue at the place where the opening is required, corrode the steel plate with acid, and finally form an opening to obtain a printing steel mesh that meets the requirements; the electroforming method is to electroform the inner wall and the opening chamfer at the opening on the basis of laser engraving the printing steel mesh, so that the inner wall of the opening is very smooth and conducive to tinning; the laser cutting method is to use laser to cut at the place where the opening is required on the printing steel mesh to obtain a printing steel mesh that meets the requirements, and the cutting parameters can be adjusted as needed to change the size.

[0039] S13: Before the reflow soldering stage, solder is printed onto the heat dissipation pad through a printed steel mesh to achieve soldering of the data transmission module.

[0040] In some embodiments, the soldering method further includes: before the reflow soldering stage, printing solder onto the heat dissipation pad printed on the circuit board through a printed steel mesh, so that the solder is distributed on each sub-pad of the heat dissipation pad.

[0041] That is to say, after the layout of the heat dissipation pad is adjusted based on the pad layout parameters, and the layout of the printed steel mesh is also adjusted accordingly based on the steel mesh design parameters, the soldering agent is printed on the heat dissipation pad printed on the circuit board through the printed steel mesh through welding equipment (such as a welding furnace) before the reflow soldering stage, so that the solder is distributed on each sub-pad of the heat dissipation pad, thereby realizing the welding of the data transmission module.

[0042] In this way, the present application draws the heat dissipation pad based on the pad layout parameters, and produces a printed steel mesh corresponding to the heat dissipation pad based on the steel mesh design parameters. Before the reflow soldering stage, the solder paste can be printed on the heat dissipation pad composed of multiple sub-pads through the printed steel mesh, so that the solder paste is evenly distributed on each sub-pad to achieve the welding of the data transmission module. Moreover, since there is a certain gap between two adjacent sub-pads, the solder paste can diffuse to the gap between the two adjacent sub-pads, thereby reducing the void rate after welding and avoiding affecting the performance of the vehicle computer and the user experience.

[0043] In some embodiments, a heat dissipation pad is drawn based on pad layout parameters, including: drawing a square matrix in the area to which the heat dissipation pad belongs based on shape parameters in the pad layout parameters; dividing the square matrix into a plurality of square blocks with equal intervals, and drawing a heat dissipation pad composed of a plurality of sub-pads in the area corresponding to the square blocks, wherein each of the plurality of sub-pads has the same shape.

[0044] Continue to refer to Figure 4 The area of ​​the heat dissipation pad in the data transmission module is 144mm 2 , based on the shape parameters, we get 144mm 2 The square matrix is ​​further divided into 36 square blocks with a vertical and horizontal interval of 0.9 mm (the 36 square blocks are distributed in the area where the heat dissipation pad belongs in a 6*6 array), and a heat dissipation pad composed of multiple sub-pads is drawn in the area corresponding to the square block. Figure 4 The sub-pad with a non-square block in the upper left corner is used to identify the location as pin 1.

[0045] Furthermore, in some embodiments, drawing the heat dissipation pad based on the pad layout parameters further includes: adjusting the size of each sub-pad to the same value based on a size parameter in the pad layout parameters.

[0046] Continue to refer to Figure 4 , based on the size parameters will be 144mm 2The sizes of the 36 sub-pads divided by the square matrix are all adjusted to 4 mm2 square blocks, so that the size of each sub-pad is the same. Among them, the size parameters and shape parameters in the pad layout parameters are parameters determined according to the characteristics of the data transmission module and the product characteristics of the intelligent cockpit domain controller. The pad layout parameters of the heat dissipation pads in the data transmission modules of different models can be adjusted according to actual needs.

[0047] In this way, by adjusting the heat dissipation pad of the data transmission module, solder paste is evenly distributed on each sub-pad after soldering, thereby reducing the void rate and manufacturing cost.

[0048] In some embodiments, based on the steel mesh design parameters, a printed steel mesh corresponding to the heat dissipation pad is manufactured, including: based on the shape parameters in the steel mesh design parameters, on the area of ​​the printed steel mesh to be cut corresponding to the heat dissipation pad, cutting multiple printed holes of the same shape as multiple sub-pads to obtain a printed steel mesh, wherein the number of printed holes in the printed steel mesh is the same as the number of sub-pads.

[0049] Furthermore, in some embodiments, based on the steel mesh design parameters, a printed steel mesh corresponding to the heat dissipation pad is produced, which also includes: based on the size parameters in the steel mesh design parameters, the size of each printed hole is adjusted to the same parameters, and the size of each printed hole is the same as the size of each sub-pad.

[0050] That is to say, after the shape and layout of the heat sink pad are adjusted, the shape and layout of the printed steel mesh for printing solder thereon also need to be adjusted 1:1.

[0051] Continue to refer to Figure 5 Based on the shape parameters in the steel mesh design parameters, the steel mesh production equipment cuts the area corresponding to the heat dissipation pad (i.e. 144mm) on the printed steel mesh to be cut (the outer frame size of the printed steel mesh to be cut is 735*735mm) by laser cutting. 2 ), 36 printing holes of the same shape as the 36 sub-pads are cut to obtain a printed steel mesh composed of 36 square blocks, and based on the size parameters in the steel mesh design parameters, the size of each square printing hole is adjusted to the same parameter, so that the size of each square printing hole and the size of each square sub-pad are both 4mm2. Among them, after cutting to obtain a printed steel mesh with a 36-grid layout, the printed steel mesh is polished. The structure of the printed steel mesh is an outer frame and a steel sheet stretching yarn + AB glue (another name for a two-liquid mixed hardening glue, one liquid is the glue, and the other liquid is the hardener). The material of the printed steel mesh is imported stainless steel SUS304, and the coating of the printed steel mesh is a nano coating.

[0052] In some embodiments, the welding method also includes: adjusting the thickness of the printed steel mesh and the heat dissipation pad corresponding areas from the initial thickness to the target thickness; when printing solder onto the heat dissipation pad through the printed steel mesh, controlling the volume of solder contained in the printing holes of the printed steel mesh to reach the target volume.

[0053] It can be understood that when the heat sink pad is a whole piece, when solder paste is printed on the heat sink pad, the coverage area of ​​the solder paste is larger; when the heat sink pad is distributed in a 6*6 matrix, when solder paste is printed on the heat sink pad, the solder paste usually only covers each sub-pad, and the gap between two adjacent sub-pads is not completely covered with solder paste. Therefore, in order to ensure that the welding performance of the optimized heat sink pad (6*6 matrix distribution) is consistent with that before optimization (whole block distribution), the present application optimizes the printed steel mesh so that when solder paste is printed on the optimized heat sink pad through the optimized printed steel mesh, the welding performance of the heat sink pad can be guaranteed, thereby ensuring the performance of the data transmission module.

[0054] Specifically, before the required printed steel mesh is cut by the steel mesh production equipment, the thickness of the printed steel mesh and the heat dissipation pad corresponding area is adjusted from the initial thickness of 0.12 mm to the target thickness of 0.15 mm. When the solder is printed on the heat dissipation pad through the printed steel mesh, the volume of the solder contained in the printing holes of the printed steel mesh is controlled to reach the target volume.

[0055] Continue to refer to Figure 5 In the 6*6 matrix area, the thickness of the steel mesh is adjusted from the initial thickness of 0.12mm to 0.15mm, and the thickness of the steel mesh outside the matrix area continues to be maintained at 0.12mm. Furthermore, when the welding equipment prints solder to the heat dissipation pad through the printed steel mesh, the volume of the solder contained in the printing holes of the printed steel mesh is controlled to reach the target volume. The target volume is the volume of the solder printed on each sub-pad when the printed steel mesh with a target thickness of 0.12mm prints solder, and the sum of the target volumes of the solder on each sub-pad is close to the target volume of the solder on a whole heat dissipation pad to ensure the welding performance of the heat dissipation pad.

[0056] It should be noted that the tension of the printed steel mesh after thickness adjustment is usually greater than 35N, the tension between two adjacent points is less than 10N, and the four sides of the printed steel mesh can be chamfered with R0.05mm to facilitate the disassembly of the printed steel mesh.

[0057] In some embodiments, the soldering method of the heat dissipation pad further includes: in a reflow soldering stage, placing the circuit board at a liquefaction temperature of the solder.

[0058] Furthermore, in some embodiments, the soldering method of the heat dissipation pad also includes: obtaining the solder liquefaction time in the reflow soldering stage; determining the solder liquefaction time in the heat absorption zone and the solder liquefaction time in the reflow soldering zone in the solder liquefaction time; and liquefying the solder according to the solder liquefaction time in the heat absorption zone and the solder liquefaction time in the reflow soldering zone.

[0059] Specifically, the liquefaction temperature varies according to the type of solder and the reflow temperature curve in the reflow process. The reflow temperature curve can be divided into four temperature zones: preheating zone (temperature between 20°C and 150°C), endothermic zone (temperature between 150°C and 190°C), reflow zone (temperature between 190°C and 210°C) and cooling zone (temperature between 210°C and 50°C).

[0060] In the preheating zone, the temperature rises slowly so that some solvents and water vapor in the solder paste can evaporate in time and activate the flux. The electronic parts (especially IC parts) are heated slowly to prepare for the high temperature later. Since the activation temperature of most fluxes is about 150°C, another purpose of uniform heating in the preheating zone is to make the solvent in the solder paste evaporate appropriately and activate the flux.

[0061] In the heat absorption zone, the solder paste is on the eve of melting, the volatiles in the solder paste will be further removed, the flux starts to work, and effectively removes the oxides on the soldering surface. If the temperature in this area rises too quickly, the rosin (flux) in the solder paste will expand and volatilize rapidly. Under normal circumstances, the rosin should slowly escape from the gaps between the solder pastes. When the rosin evaporates too quickly, quality problems such as pores, tin explosion, and solder beads will occur.

[0062] In the reflow zone (the area with the highest temperature in the entire reflow zone, also commonly called liquid holding time), the tin or nickel in the solder and the copper on the pad form intermetallic compounds due to diffusion;

[0063] In the cooling zone, the solder paste cools and solidifies the solder joints, which will be prepared for the subsequent data transmission module assembly process. Therefore, in the reflow soldering stage, the circuit board printed with the heat dissipation pad is placed at the liquefaction temperature of the solder, so that the solder on the heat dissipation pad melts and then the heat dissipation pad is soldered by SMT. Only when the temperature is high will larger bubbles be generated, so only the two areas with high temperature need to be adjusted.

[0064] It can be understood that in the SMT soldering process of the heat dissipation pad, bubbles are usually generated in the welding stage with higher temperature. Therefore, in order to further optimize the void rate problem, the present application adjusts the liquefaction time of the solder in the higher temperature heat absorption zone and the reflow soldering zone in the reflow soldering stage to minimize the generation of bubbles and ensure that the hardness of the data transmission module meets the standard.

[0065] Specifically, first obtain the solder liquefaction time of the reflow soldering stage, then determine the solder liquefaction time of the heat absorption zone in the solder liquefaction time, the liquefaction temperature of the solder in the heat absorption zone Soak is 150℃-180℃, and the solder liquefaction time is 60S-100S, and determine the solder liquefaction time of the reflow soldering zone, the liquefaction temperature of the solder in the reflow soldering zone Reflow is greater than 220℃, the solder liquefaction time is 60S-80S, and the liquefaction temperature peak PeakTem of the reflow soldering zone Reflow is between 235℃-250℃, finally, liquefy the solder according to the solder liquefaction time of the heat absorption zone and the solder liquefaction time of the reflow soldering zone, thereby reducing bubbles in the welding process.

[0066] In summary, this application adjusts the shape and layout of the GND PAD of the data transmission module, and also makes corresponding adjustments to the structure, shape and layout of the steel mesh, and makes corresponding adjustments to the reflow temperature curve Profile during the reflow process. Through multiple rounds of experiments, optimization and verification, the void rate of the data transmission module is reduced from 85% to below 40%, and the defective rate of the data transmission module is reduced from 85% to below 13%, ensuring the performance of the vehicle computer and the user experience.

[0067] The welding method of this embodiment can be executed by any appropriate electronic device with data processing capability, including but not limited to: a server, a mobile terminal (such as a mobile phone, a PAD, etc.) and a PC, etc.

[0068] Figure 6 The figure is a structural block diagram of a welding system according to one embodiment of the present application.

[0069] like Figure 6 As shown, the welding system 600 can perform Figure 1 The welding method comprises: a welding system 600 including: a drawing device 601, which draws a heat dissipation pad based on a pad layout parameter so as to print a heat dissipation pad composed of a plurality of sub-pads on a circuit board of a data transmission module, wherein the pad layout parameter includes at least a shape parameter and a size parameter, and a spacing between two adjacent sub-pads among the plurality of sub-pads is greater than a preset spacing; a steel mesh production device 602, which produces a printed steel mesh corresponding to the heat dissipation pad based on a steel mesh design parameter, wherein the steel mesh design parameter includes at least a shape parameter and a size parameter, wherein the shape parameter in the steel mesh design parameter is the same as the shape parameter in the pad layout parameter, and the size parameter in the steel mesh design parameter is the same as the size parameter in the pad layout parameter; and a welding device 603, which prints solder onto the heat dissipation pad through a printed steel mesh before a reflow soldering stage to realize welding of the data transmission module.

[0070] In some embodiments of the present application, the drawing device 601 is specifically used to: draw a square matrix in the area to which the heat dissipation pad belongs based on the shape parameters in the pad layout parameters; divide the square matrix into a plurality of square blocks with equal intervals, and draw a heat dissipation pad composed of a plurality of sub-pads in the area corresponding to the square blocks, wherein each of the plurality of sub-pads has the same shape.

[0071] In some embodiments of the present application, the drawing device 601 is specifically used to: adjust the size of each sub-pad to the same value based on the size parameter in the pad layout parameter.

[0072] In some embodiments of the present application, the steel mesh production equipment 602 is specifically used to: based on the shape parameters in the steel mesh design parameters, cut multiple printing holes of the same shape as multiple sub-pads on the area corresponding to the printed steel mesh to be cut and the heat dissipation pad to obtain a printed steel mesh, wherein the number of printing holes in the printed steel mesh is the same as the number of sub-pads.

[0073] In some embodiments of the present application, the steel mesh production device 602 is specifically used to: based on the size parameters in the steel mesh design parameters, adjust the size of each printing hole to the same parameters, and the size of each printing hole is the same as the size of each sub-pad.

[0074] In some embodiments of the present application, the welding method also includes an adjustment module (not shown in the figure): adjusting the thickness of the printed steel mesh and the heat dissipation pad in the area corresponding to the initial thickness to the target thickness; when printing solder to the heat dissipation pad through the printed steel mesh, controlling the volume of the solder contained in the printing holes of the printed steel mesh to reach the target volume.

[0075] In some embodiments of the present application, the welding device 603 is specifically used to: before the reflow soldering stage, print the solder onto the heat dissipation pad printed on the circuit board through the printed steel mesh, so that the solder is distributed on each sub-pad of the heat dissipation pad.

[0076] In some embodiments of the present application, the soldering device 603 is specifically used to place the circuit board at the liquefaction temperature of the solder during the reflow soldering stage.

[0077] In some embodiments of the present application, the welding equipment 603 is specifically used to: obtain the solder liquefaction time of the reflow soldering stage; determine the solder liquefaction time of the heat absorption zone and the solder liquefaction time of the reflow soldering zone in the solder liquefaction time; liquefy the solder according to the solder liquefaction time of the heat absorption zone and the solder liquefaction time of the reflow soldering zone.

[0078] In addition, the technical solutions of the above-mentioned embodiments of the present application can be combined with each other and are not limited here.

[0079] According to the welding system of the embodiment of the present application, a heat dissipation pad is drawn based on the pad layout parameters, and a printed steel mesh corresponding to the heat dissipation pad is manufactured based on the steel mesh design parameters. Before the reflow soldering stage, the solder paste can be printed on the heat dissipation pad composed of multiple sub-pads through the printed steel mesh, so that the solder paste is evenly distributed on each sub-pad to achieve the welding of the data transmission module. Moreover, since there is a certain interval between two adjacent sub-pads, the solder paste can diffuse to the interval between the two adjacent sub-pads, thereby reducing the void rate after welding and avoiding affecting the performance of the vehicle computer and the user experience.

[0080] The welding system 600 of this embodiment is used to implement the corresponding welding methods in the aforementioned multiple method embodiments, and has the beneficial effects of the corresponding method embodiments, which will not be described in detail here. In addition, the functional implementation of each module in the welding system 600 of this embodiment can refer to the description of the corresponding parts in the aforementioned method embodiments, which will not be described in detail here.

[0081] It should be pointed out that, according to the needs of implementation, the various components / steps described in the embodiments of the present application can be split into more components / steps, or two or more components / steps or partial operations of components / steps can be combined into new components / steps to achieve the purpose of the embodiments of the present application.

[0082] The above-mentioned method according to the embodiment of the present application can be implemented in hardware, firmware, or implemented as software or computer code that can be stored in a recording medium (such as a CD ROM, RAM, floppy disk, hard disk or magneto-optical disk), or implemented as a computer code originally stored in a remote recording medium or a non-temporary machine-readable medium downloaded through a network and to be stored in a local recording medium, so that the method described herein can be stored in such software processing on a recording medium using a general-purpose computer, a dedicated processor or programmable or dedicated hardware (such as an ASIC or FPGA). It can be understood that a computer, a processor, a microprocessor controller or programmable hardware includes a storage component (e.g., RAM, ROM, flash memory, etc.) that can store or receive software or computer code, and when the software or computer code is accessed and executed by a computer, a processor or hardware, the welding method described herein is implemented. In addition, when a general-purpose computer accesses the code for implementing the welding method shown here, the execution of the code converts the general-purpose computer into a dedicated computer for executing the welding method shown here.

[0083] Those of ordinary skill in the art will appreciate that the units and method steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the embodiments of the present application.

[0084] The above implementation methods are only used to illustrate the embodiments of the present application, and are not intended to limit the embodiments of the present application. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the embodiments of the present application. Therefore, all equivalent technical solutions also belong to the scope of the embodiments of the present application, and the scope of patent protection of the embodiments of the present application should be defined by the claims. The systems, devices or modules described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions.

Claims

1. A welding method, characterized in that: The method comprises: Drawing a heat dissipation pad based on a pad layout parameter so as to print the heat dissipation pad composed of a plurality of sub-pads on a circuit board of a data transmission module, wherein the pad layout parameter includes at least a shape parameter and a size parameter, and an interval between two adjacent sub-pads of the plurality of sub-pads is greater than a preset interval; Based on the steel mesh design parameters, the printed steel mesh corresponding to the heat dissipation pad is manufactured, the steel mesh design parameters at least include shape parameters and size parameters, the shape parameters in the steel mesh design parameters are the same as the shape parameters in the pad layout parameters, and the size parameters in the steel mesh design parameters are the same as the size parameters in the pad layout parameters; Before the reflow soldering stage, soldering agent is printed on the heat dissipation pad through the printed steel mesh to achieve soldering of the data transmission module.

2. The welding method according to claim 1, characterized in that: Draw thermal pads based on pad layout parameters, including: Based on the shape parameters in the pad layout parameters, a square matrix is ​​drawn in the area to which the heat dissipation pad belongs; The square matrix is ​​divided into a plurality of square blocks with equal intervals, and the heat dissipation pad composed of the plurality of sub-pads is drawn in the area corresponding to the square block, wherein each of the plurality of sub-pads has the same shape.

3. The welding method according to claim 2, characterized in that: Draw the thermal pad based on the pad layout parameters, including: Based on the size parameter in the pad layout parameters, resize each sub-pad to the same value.

4. The welding method according to claim 3, characterized in that: Based on the steel mesh design parameters, the printed steel mesh corresponding to the heat dissipation pad is manufactured, including: Based on the shape parameters in the steel mesh design parameters, multiple printing holes of the same shape as the multiple sub-pads are cut on the area of ​​the printed steel mesh to be cut corresponding to the heat dissipation pad to obtain the printed steel mesh, wherein the number of printed holes in the printed steel mesh is the same as the number of sub-pads.

5. The welding method according to claim 4, characterized in that: Based on the steel mesh design parameters, the printed steel mesh corresponding to the heat dissipation pad is manufactured, further comprising: Based on the size parameters in the steel mesh design parameters, the size of each printing hole is adjusted to the same parameter, and the size of each printing hole is the same as the size of each sub-pad.

6. The welding method according to claim 5, characterized in that: The method further comprises: Adjusting the thickness of the printed steel mesh and the steel mesh in the area corresponding to the heat dissipation pad from the initial thickness to the target thickness; When printing solder onto the heat dissipation pad through the printing steel mesh, the volume of the solder contained in the printing holes of the printing steel mesh is controlled to reach a target volume.

7. The welding method according to claim 1, characterized in that: The method further comprises: Before the reflow soldering stage, the solder is printed onto the heat dissipation pad printed on the circuit board through the printed steel mesh, so that the solder is distributed on each sub-pad of the heat dissipation pad.

8. The welding method according to claim 7, characterized in that: The method further comprises: During the reflow soldering stage, the circuit board is exposed to the liquidus temperature of the solder.

9. The welding method according to claim 8, characterized in that: The method further comprises: Obtaining the solder liquefaction time in the reflow soldering stage; Determining the solder liquefaction time of the heat absorption zone and the solder liquefaction time of the reflow zone in the solder liquefaction time; The solder is liquefied according to the solder liquefaction time in the heat absorption zone and the solder liquefaction time in the reflow zone.

10. A welding system, characterized in that: include: A drawing device, drawing a heat dissipation pad based on a pad layout parameter so as to print the heat dissipation pad composed of a plurality of sub-pads on a circuit board of a data transmission module, wherein the pad layout parameter includes at least a shape parameter and a size parameter, and an interval between two adjacent sub-pads of the plurality of sub-pads is greater than a preset interval; A stencil manufacturing device, which manufactures the printed stencil corresponding to the heat dissipation pad based on stencil design parameters, wherein the stencil design parameters at least include shape parameters and size parameters, wherein the shape parameters in the stencil design parameters are the same as the shape parameters in the pad layout parameters, and the size parameters in the stencil design parameters are the same as the size parameters in the pad layout parameters; The welding equipment prints welding agent onto the heat dissipation pad through the printed steel mesh before the reflow soldering stage to realize the welding of the data transmission module.

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