3D galvanometer flying laser welding method and welding system

Abstract

According to the 3D galvanometer flying laser welding method and system, the machining positions of all busbars are scanned and height coordinates are established through a 3D vision module before laser welding, the characteristic that a 3D galvanometer can be finely adjusted in the Z-axis direction is utilized, the welding focus can be adjusted corresponding to each needed welding height, and the welding precision is improved. Therefore, each busbar can be independently welded, the welding machining precision is high, meanwhile, breadth limitation is avoided, the busbars in rows can be continuously welded, a laser power supply does not need to be turned off in the midway, coordinate system light cutting is recognized through a galvanometer, the laser starting and stopping frequency is reduced, the service life of the laser is prolonged, the welding efficiency is improved, and the production cost is reduced. And the station switching stroke is reduced, and the welding operation takt is accelerated.

Description

Technical Field

[0001] This invention relates to the field of laser processing technology, and in particular to a 3D galvanometer flying laser welding method and welding system. Background Technology

[0002] In the power battery packs of new energy vehicles, the welding quality of the busbar is crucial. Traditional robots typically use 2D galvanometer systems for operation. 2D galvanometer systems can only perform planar welding. For busbars with height differences (due to cell height tolerances or curved surface designs), the robot needs to frequently adjust the Z-axis (the planar direction is composed of the X and Y axes, and the Z-axis is the height direction perpendicular to the plane). This makes high-speed "flying welding" impossible, resulting in large motion inertia, low welding efficiency, complex programming, and high requirements for workpiece consistency.

[0003] When using a 2D galvanometer system for welding, multiple battery cell arrays are laid out on the processing plane. After the busbars are placed on the cells, the 2D laser galvanometer performs welding on each cell on the busbars. Due to the image size limitation of the galvanometer system itself, a unit pressing mechanism needs to be designed according to the image size. In a single-row busbar, the image size can usually only cover a few busbars in the row. The unit pressing mechanism corresponds to several busbars within this unit, each with an independent copper nozzle pressing device. The copper nozzle pressing device has cutouts corresponding to the welding positions on the busbars for laser welding operations. The copper nozzle is used to introduce nitrogen gas during welding and to extract waste gas and welding slag. When using a 2D galvanometer system for welding, due to the image size limitation of the 2D galvanometer, only one busbar within a unit can be operated at a time. When processing a large number of battery cell busbar arrays, the operation needs to be performed sequentially.

[0004] To address this, existing improvements to 2D galvanometer systems involve designing two sets of unit pressing mechanisms, operating in a dual-station configuration. While one set of mechanisms is pressing down and the galvanometer is performing laser welding, the other set moves to the next busbar to be processed and presses down. After the previous busbar is welded, the laser galvanometer is turned off, moves to the next station, and then turned on again for welding. This allows the next set of units to be pressed down and positioned during the welding process of the previous set, improving processing efficiency. However, this design requires space for the displacement of the unit pressing mechanisms, typically resulting in a long distance between the two sets of pressing mechanisms and a long travel distance between them. After the laser galvanometer finishes processing the previous unit, it needs to be turned off, moved to the next processing unit, and then turned on again. This workflow requires frequent opening and closing of the laser galvanometer, affecting its lifespan.

[0005] Meanwhile, in 2D galvanometer welding, for welding points within the busbars of the same unit, the rangefinder on the existing 2D galvanometer is used. Before welding, the rangefinder measures the height of the position to be welded and calculates the average height data. During welding, the average value is used as the reference height for actual processing. This reference height has height differences for each actual height, resulting in differences in welding accuracy. Summary of the Invention

[0006] The technical problem to be solved by this invention is: in order to overcome the shortcomings of the prior art, this invention provides a 3D galvanometer flying laser welding method and welding system. Before laser welding, the processing position of each busbar is scanned and the height coordinates are established. Utilizing the characteristic of the 3D galvanometer itself that can be finely adjusted in the Z-axis direction, the welding focus can be adjusted according to the welding height required for each busbar, thereby realizing independent welding for each busbar. The welding processing accuracy is high, and it is not limited by the width. Rows of busbars can be welded continuously without turning off the laser in the middle, reducing the number of laser start-ups and shutdowns. This not only extends the life of the laser but also improves welding efficiency, reduces the station switching stroke, and speeds up the welding operation cycle.

[0007] The technical solution adopted by the present invention to solve its technical problem is: a 3D galvanometer flying laser welding method for welding cell terminals and busbars. The method uses a 3D vision module to obtain the three-dimensional position information of each cell terminal and busbar welding point, and uses a 3D galvanometer to perform welding actions on each welding point according to the three-dimensional position information.

[0008] This method leverages the inherent Z-axis dynamic focusing module of the 3D galvanometer to achieve dynamic focus adjustment in the Z-axis during laser welding. This allows for independent operation based on the actual height of each welding point, effectively improving welding precision. Furthermore, for workpieces in the same row, independent operation for each workpiece overcomes the image frame limitations of traditional 2D galvanometers. During the entire row of welding operations, there is no need to turn off the light or switch positions, effectively accelerating the welding cycle and improving welding efficiency.

[0009] Furthermore, this 3D galvanometer flying laser welding method includes a 3D precision measurement step and a 3D welding step. In the 3D precision measurement step, the 3D vision module flies at a constant speed along the bus distribution direction and scans to obtain the three-dimensional position information of each cell electrode and bus welding point. In the 3D welding step, the 3D galvanometer performs welding actions on each cell electrode and bus based on the three-dimensional position information obtained in the 3D precision measurement step. The difference in height between different cell electrodes and buses in the Z direction is adjusted by the Z-direction dynamic focusing module of the 3D galvanometer by shifting the focus point in the Z direction.

[0010] Furthermore, prior to the 3D precision measurement step, there is a 2D coarse positioning step. In this step, the 2D vision module moves above the battery cell terminals and busbars to be welded, and uses its 2D camera to identify the busbar position information. This position information provides the basis for the 3D precision measurement step. The 2D coarse positioning operation provides basic positioning information for the welding operation, facilitating the calibration of the basic offset during welding.

[0011] A 3D galvanometer flying laser welding system is used to weld busbars to battery cell terminals. The system includes a frame and a robot. The frame has Y-axis moving modules distributed along the Y-axis, and X-axis moving modules are distributed on the Y-axis moving modules. The X-axis moving modules are equipped with a 3D vision module and a copper nozzle pressing mechanism. The 3D vision module moves along the X-axis and scans to acquire the three-dimensional position information of the welding point between the battery cell terminal and the busbar. The copper nozzle pressing mechanism presses downward against the busbar to be welded. The robot has a manipulator arm with a 3D galvanometer fixed to it. When the manipulator arm moves above a row of workpieces to be welded, it drives the 3D galvanometer to move along the X-axis and perform welding operations on the workpieces below.

[0012] Furthermore, after the robot's manipulator arm drives the 3D galvanometer to perform welding operations along the X-axis, it then drives the 3D galvanometer to move along the Y-axis to the next row of workpieces to be welded.

[0013] Furthermore, the robot's manipulator arm is equipped with a 2D vision module, which includes a 2D camera. The robot manipulator arm carries the 2D camera and moves horizontally along the X and Y directions respectively to identify and locate the workpiece to be welded below.

[0014] Furthermore, the battery has several rows of workpieces to be welded, and there are positioning posts at the four corners of the battery's circumference. A 2D camera identifies the position information of the positioning posts, and the robot's manipulator adjusts its basic position in the X and Y directions according to the position information of the positioning posts.

[0015] Preferably, the Y-axis moving module includes a Y-axis power mechanism and Y-axis guide rails symmetrically arranged on the frame. A Y-axis slider is slidably arranged on the Y-axis guide rail. The Y-axis power mechanism drives the Y-axis slider to slide along the Y-axis guide rail. A Z-axis slide rail is fixed on the Y-axis slider. A Z-axis power mechanism and a Z-axis slider are arranged on the Z-axis slide rail. The Z-axis slider moves along the Z-axis slide rail under the drive of the Z-axis power mechanism. The X-axis moving module is arranged on the corresponding Z-axis sliders on both sides.

[0016] Furthermore, the X-axis moving module includes an X-axis truss, a 3D vision module, and a copper nozzle pressing mechanism. A line scanning servo mechanism is slidably mounted on the X-axis truss. The 3D vision module is mounted on the line scanning servo mechanism and is driven by the line scanning servo mechanism to slide along the X-axis. A copper nozzle pressing mechanism is also provided on the X-axis truss.

[0017] Furthermore, on the end face of the X-axis truss corresponding to the copper nozzle pressing mechanism, a servo copper nozzle moving mechanism is provided along the X-axis. The servo copper nozzle moving mechanism includes a copper nozzle guide rail and an X-axis servo mechanism. The X-axis servo mechanism drives the copper nozzle pressing mechanism to translate along the copper nozzle guide rail in the X-axis direction. The arrangement of the copper nozzle guide rail and the X-axis servo mechanism further expands the workable space in the X-axis direction, enabling it to address situations where the busbar distribution of the battery is spaced out in the X-axis direction, further expanding the range of processing and adaptability.

[0018] The beneficial effects of this invention are that the 3D orthogonal flying laser welding method and welding system provided by this invention utilize the Z-axis height compensation of the 3D galvanometer itself. Each busbar can be scanned and its height coordinates established through a vision system. The welding focus of the 3D galvanometer is adjusted according to the height of each busbar, and processing is performed independently. During processing, it is not limited by the original width, enabling sequential and continuous processing of the entire row of busbars, reducing the station switching travel, effectively accelerating the operation cycle. During the entire row welding operation, the laser beam is cut based on the coordinate system identified by the galvanometer, eliminating the need to turn off the laser power supply, effectively extending the laser's lifespan. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] Figure 1 This is a schematic diagram of the welding system in an embodiment of the present invention.

[0021] Figure 2 This is a schematic diagram of the 3D galvanometer in an embodiment of the present invention.

[0022] In the diagram: 1. Manipulator arm; 2. Robot; 3. Copper nozzle guide rail; 4. X-axis servo mechanism; 5. Copper nozzle pressing mechanism; 6. Line scan servo mechanism; 7. 3D vision module; 8. Y-axis guide rail; 9. Y-axis slider; 10. Frame; 11. Battery cell; 12. Busbar; 13. Battery; 14. Z-axis slider; 15. Z-axis guide rail; 16. X-axis truss; 17. Z-axis power mechanism; 18. 3D galvanometer; 19. XY scanning galvanometer. Detailed Implementation

[0023] The invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention in a schematic manner. Therefore, they only show the components relevant to the invention, and the orientations and references (e.g., up, down, left, right, etc.) are only used to aid in the description of the features in the drawings. Therefore, the following specific embodiments are not intended to be limiting, and the scope of the claimed subject matter is defined solely by the appended claims and their equivalents.

[0024] This invention provides a 3D galvanometer flying laser welding method for welding busbars 12 to the terminals of battery cells 11 on a battery 13. Typically, battery cells 11 are arranged in an array on the battery 13, and busbars 12 are located on top of the cells 11. The busbars 12 and the cells 11 need to be welded together using a laser. In this embodiment, the workpieces to be welded are the terminals of the battery cells 11 and their corresponding busbars 12.

[0025] In this method, a 3D vision module 7 is used to acquire the three-dimensional position information of the welding points between the electrode post of each battery cell 11 and the busbar 12. A 3D galvanometer 18 is used to perform welding actions on each welding point based on the three-dimensional position information. In the three-dimensional position information acquired by the 3D vision module 7, the Z-axis height difference is adjusted as needed by the Z-axis dynamic focusing module of the 3D galvanometer 18, thereby enabling independent and precise welding actions based on the accurate welding height of each workpiece during laser welding. When welding an entire row, since the 3D vision module 7 can scan the three-dimensional position information of the entire row of workpieces to be welded, and the line scanning action of the 3D vision module 7 is separated from the welding action, the welding action is not limited by the width of the swath when the vision module acquires the three-dimensional position information. Therefore, welding actions can be performed on the entire row of workpieces without turning off the light.

[0026] Specifically, the 3D galvanometer flying laser welding method includes a 2D coarse positioning step, a 3D fine measurement step, and a 3D welding step.

[0027] 2D coarse positioning steps: The 2D vision module moves above the terminal of the battery cell 11 and the busbar 12 to be welded. The 2D camera of the 2D vision module identifies the position information of the busbar 12, which provides the positioning basis for the 3D fine measurement step. The 2D coarse positioning operation can provide basic positioning information for the welding operation, making it easy to calibrate the basic offset with this positioning information during welding.

[0028] 3D precision measurement steps: The 3D vision module 7 flies at a constant speed along the distribution direction of the busbar 12 and scans to obtain the three-dimensional position information of the welding point between the electrode of each cell 11 and the busbar 12.

[0029] 3D welding steps: Based on the three-dimensional position information obtained from the 3D precision measurement steps, the 3D galvanometer 18 performs welding operations on the terminal post of each battery cell 11 and the busbar 12 respectively. The difference in height between the terminal post of different battery cells 11 and the busbar 12 in the Z direction is adjusted by the Z-direction dynamic focusing module of the 3D galvanometer 18 to shift the focus in the Z direction.

[0030] This method utilizes the advantages of the Z-axis dynamic focusing module inherent in the 3D galvanometer 18 to achieve dynamic adjustment of the focus in the Z-axis during laser welding. This allows for independent operation based on the actual height of each welding point, effectively improving the precision of the welding operation. Furthermore, for workpieces in the same row, independent operation for each workpiece overcomes the image size limitations of the original 2D galvanometer. During the entire row of welding operations, there is no need to turn off the light or switch positions, effectively accelerating the welding cycle and improving welding efficiency. Compared to the original method using a 2D galvanometer, which required intermittent welding with multiple light switching operations due to image size limitations, this method uses the 3D galvanometer 18 for welding. During the welding process in the same row, there is no need to turn off the light. The 3D galvanometer 18, which can be used for welding, can be driven by the robot 2's manipulator arm 1 in a smooth linear motion, welding sequentially without interruption, hence the term "flying."

[0031] It should be noted that in this embodiment, "light off" refers to turning off the laser power supply. The statement "no need to turn off the light during the entire row of welding" means that during the welding process of the entire row of workpieces, the laser power supply does not need to be turned off. The laser beam is cut off during the welding process by the galvanometer identifying the coordinate system; all these optical actions are functions of the 3D galvanometer 18 itself. Once the entire row of welding is completed, the laser power supply of the 3D galvanometer 18 will be turned off and then turned on again after moving to the starting position of the next row of workpieces.

[0032] Based on this design concept, this embodiment introduces a 3D galvanometer 18 into the laser welding system, and designs as follows: Figure 1 This illustrates a 3D galvanometer flying laser welding system. In Figure 1 In the direction settings, the X and Y directions are located on the horizontal plane, with the X and Y directions intersecting at 90°, while the Z direction is perpendicular to the horizontal plane.

[0033] The 3D galvanometer flying laser welding system includes a frame 10 and a robot 2. The robot 2 has a manipulator arm 1, which can be driven by a control system and a drive system to move in the X, Y, and Z directions. A 2D vision module and a 3D galvanometer 18 are fixed on the manipulator arm 1. The 2D vision module preferably uses a 2D camera. The robot 2 manipulator arm 1, carrying the 2D camera, moves horizontally along the X and Y directions to identify and locate the workpiece to be welded below. This positioning information is used to locate the battery 13 below before the welding action. The outline of the busbar is identified through image processing, and the offset from the standard position is calculated, which facilitates the adjustment of the robot arm's offset as needed.

[0034] The racks 10 are typically arranged in pairs. In this embodiment, there are two racks 10, which are distributed parallel to each other in the X direction. A Y-axis moving module is connected between the ends of the two racks 10 on the same side, and an X-axis moving module is connected to the Y-axis moving module at both ends. Thus, the Y-axis moving module and the X-axis moving module form a frame structure, which is used to support and drive the 3D vision module 7 and the copper nozzle pressing mechanism 5 required in the laser welding process.

[0035] Specifically, the Y-axis movement module includes a Y-axis power mechanism and Y-axis guide rails 8. The ends of the two frames 10 on the same side are connected by Y-axis guide rails 8, and the Y-axis guide rails 8 on both sides are symmetrically arranged. Each Y-axis guide rail 8 has a sliding Y-axis slider 9, and the Y-axis power mechanism drives the Y-axis slider 9 to slide along the Y-axis guide rail 8. In this embodiment, when there are two X-axis movement modules, each Y-axis guide rail 8 has two Y-axis sliders 9, and the Y-axis sliders 9 on the two Y-axis guide rails 8 are arranged in a one-to-one correspondence, with the X-axis movement module positioned between the pairs of Y-axis sliders 9.

[0036] To effectively achieve the downward pressing action of the copper nozzle pressing mechanism 5, a Z-axis slide rail 15 is fixed on the Y-axis slider 9. The Z-axis slide rail 15 is equipped with a Z-axis power mechanism 17 and a Z-axis slider 14. The Z-axis slider 14 moves along the Z-axis slide rail 15 under the drive of the Z-axis power mechanism 17. The two ends of the X-axis moving module are respectively mounted on the corresponding Z-axis sliders 14 on both sides. The Z-axis power mechanism 17 controls the X-axis moving module to rise or fall in the Z-direction.

[0037] The X-axis moving module includes an X-axis truss 16, a 3D vision module 7, and a copper nozzle pressing mechanism 5. The 3D vision module 7 moves along the X-axis and scans to acquire the three-dimensional position information of the welding point between the battery cell 11 electrode and the busbar 12, accurately identifying the three-dimensional center coordinate point of the weld. The copper nozzle pressing mechanism 5 moves up and down along the Z-axis with the overall movement of the X-axis moving module, pressing down on the busbar 12 to be welded, realizing the pressing action during the welding process, and sucking and venting air during the welding process. The copper nozzle pressing mechanism 5 can adopt the same structure as the copper nozzle pressing mechanism 5 used in existing laser welding operations using 2D galvanometers. In the size design, it is adaptively improved according to the number and size of the battery cells 11 and busbars 12 arranged on the battery 13, based on the number of rows.

[0038] One end of the X-axis truss 16 is fixed to the left Z-axis slider 14, and the other end is fixed to the right Z-axis slider 14. The Z-axis power mechanism 17 drives the Z-axis slider 14, which in turn drives the X-axis truss 16 to move up and down. The corresponding Y-axis sliders 9 on both sides are driven by the Y-axis power mechanism to adjust the position of the X-axis truss 16 in the Y-axis.

[0039] A line scanning servo mechanism 6 is slidably mounted on the X-axis truss 16. The 3D vision module 7 is mounted on the line scanning servo mechanism 6 and is driven by the line scanning servo mechanism 6 to slide along the X-axis. In actual selection, the line scanning servo mechanism 6 can be in the form of a linear rail + slider + servo power mechanism. The 3D vision module 7 is fixed on the slider, which is controlled by the linear rail to slide along the rail. The 3D vision module 7 flies at a constant speed along the preset path (the linear rail on the X-axis truss 16). The line laser contour scanner of the 3D vision module 7 starts working, scanning and acquiring the three-dimensional coordinate information of the contour of the cross-section of the weld to be welded between the lower core column and the busbar 12, thereby providing coordinate information for the 3D galvanometer 18 to perform independent and precise operation on each workpiece to be welded.

[0040] Furthermore, if the battery 13 is located in the X-axis and the busbars 12 are distributed with a large gap, a servo copper nozzle moving mechanism can be provided along the X-axis on the end face of the copper nozzle pressing mechanism 5 corresponding to the X-axis truss 16. The servo copper nozzle moving mechanism can preferably be a copper nozzle guide rail 3 and an X-axis servo mechanism 4. In this case, the copper nozzle pressing mechanism 5 is fixed to one end of the X-axis servo mechanism 4 and is driven by the X-axis servo mechanism 4 to translate along the copper nozzle guide rail 3, realizing the translational movement of the copper nozzle pressing mechanism 5 in the X-axis. During the translational movement, cables and other items carried on the copper nozzle pressing mechanism 5 are protected by a drag chain installed between the servo mechanism and the rail. Thus, according to the distribution pattern of the workpieces to be welded in the X-axis, they can be pressed in groups as needed and welded by the 3D galvanometer 18. Similarly, unlike the width limitation of the 2D galvanometer, there is no limitation on the group length and number of workpieces to be welded; the length, width, and height of the copper nozzle pressing mechanism 5 can be adaptively designed according to the actual group length and number.

[0041] When using this welding system, the battery 13 needs to be transferred into the frame 10 via an AGV (Automated Guided Vehicle). After transfer, the battery 13 needs to be coarsely positioned using a 2D vision module. To achieve this, positioning posts need to be designed on the surface of the battery 13 for 2D camera recognition. In this embodiment, several cells 11 are arranged in an array on the battery 13, and each cell 11 has a busbar 12. The welding system is used to weld the cells 11 to the corresponding busbars 12. Positioning posts are located at the four corners of the battery 13. A worktable is located between the two open frames 10. After the AGV transfers the battery 13 to the worktable, the robot 2's manipulator arm 1 moves the 2D camera to the four corner positioning posts (photo capture positions) of the battery 13, captures and analyzes the positioning post position signals, and initially obtains the approximate area of ​​the workpiece to be welded. At this time, a QR code can also be used to identify the workpiece model on the battery 13. During 2D camera recognition, this code is used to identify the workpiece information and, combined with the positioning post position signals, calculates the offset between the position of the workpiece to be welded on the battery 13 and the standard position.

[0042] The X-axis moving module, Y-axis moving module, Z-axis slide rail 15, etc., drive the copper nozzle pressing mechanism 5 to perform position compensation in the X / Y / Z directions according to the offset. After the copper nozzle pressing mechanism 5 moves to the welding start point, it presses down, so that the copper nozzle presses the busbar and the battery cell 11 electrode to the preset pressure range.

[0043] The 3D vision module 7 begins to fly at a constant speed along a preset path. During flight, the line laser contour scanner in the 3D vision module 7 operates, acquiring the contour point cloud of the weld cross-section at each welding location on the workpiece to be welded. The control system processes the contour point cloud in real time: first, noise filtering is performed, and then edge extraction or centerline extraction algorithms are used to accurately identify the three-dimensional center coordinates of the weld, especially the position information of the pole welding point in the Z-axis.

[0044] Robot 2's manipulator arm 1, carrying a 3D galvanometer 18, performs laser welding on rows of workpieces after line scanning. The 3D galvanometer 18 includes an XY scanning galvanometer 19 and a Z-axis dynamic focusing module, as well as a weld pool detection camera designed by Shanghai Integrated Circuits. During operation, based on the three-dimensional position information of each workpiece acquired by the 3D vision module 7, the manipulator arm 1 begins to move along an S-shaped path (X and Y axes) at a speed of 200 mm / s. The Z-axis dynamic focusing module of the 3D galvanometer 18 dynamically adjusts the focal length based on the height data of the electrode welding point in the Z-axis, ensuring that the welding focus falls on the actual welding position of each workpiece and maintaining a constant laser power density. The weld pool detection camera captures images in real time as the 3D galvanometer moves. If the system detects abnormal spatter, it transmits the abnormal signal to the control system, which instantly (at the microsecond level) reduces the laser power by 5%, restoring it after 10 ms, effectively suppressing defects.

[0045] In actual operation, for rows of workpieces to be welded, a 3D line scan can be performed on the entire row of workpieces first to obtain their three-dimensional coordinates. Then, the robot 2 can be controlled to perform laser welding using the 3D galvanometer 18. Alternatively, the 3D line scan and the 3D galvanometer 18 welding can be organically combined, as long as each workpiece is scanned first and then the 3D galvanometer 18 welding is performed. For example, during line scanning, the line laser contour scanner of the 3D vision module 7 moves first, scanning the weld seam with an advance of approximately 50mm ahead of the welding point of the 3D galvanometer 18, providing real-time height data. The 3D galvanometer 18 then dynamically compensates for the Z-axis based on this height data, dynamically adjusting the focus position.

[0046] In this welding operation, for each workpiece to be welded, line scanning three-dimensional positioning comes first, followed by laser welding. Therefore, during the welding process, the Z-axis dynamic focusing module of the 3D galvanometer 18 can be used to independently adjust the focus of each workpiece in terms of height. Compared with the traditional welding operation that uses an average fixed focus height, it has higher welding accuracy.

[0047] In this embodiment, to further accelerate the cycle time, two sets of X-axis moving modules are designed in the X-axis direction. Similarly, the Y-axis guide rail 8 is also divided into two segments along the Y-axis according to the group of X-axis moving modules, with one segment corresponding to one group of X-axis moving modules. This avoids additional vibration interference to the other group of X-axis moving modules caused by vibration during the movement / processing of one group of X-axis moving modules, further ensuring processing accuracy.

[0048] When one set of X-axis moving modules is processing, while the corresponding X-axis moving module is performing laser welding, another set of X-axis moving modules can move to the position of another row of workpieces to be welded, performing the initial copper nozzle pressing and 3D vision module 7 line scanning actions. After the robot 2's operating arm 1 drives the 3D galvanometer 18 to complete the operation of the upper row, the robot 2's operating arm 1 drives the 3D galvanometer 18 to move along the Y direction to the next row of workpieces to be welded corresponding to the position of the next set of X-axis moving modules, and then perform the welding operation. Traditional 2D galvanometers need to be turned off when switching X-axis moving module groups, and also when switching workpieces to be welded in the same row according to width. However, the 3D galvanometer 18 provided in this embodiment only needs to be turned off when switching different groups of X-axis moving modules, which speeds up the cycle time and reduces the switching losses of laser welding within the galvanometer.

[0049] This 3D flying laser welding method and system utilizes the Z-axis height compensation of the 3D galvanometer 18. A vision system scans each busbar 12 and establishes its height coordinates. The welding focus of the 3D galvanometer 18 is adjusted according to the height of each busbar 12, allowing for independent processing. During processing, it is not limited by the width of the original 2D camera, enabling sequential and continuous processing of the entire row of busbars 12. This reduces station switching travel, effectively speeds up the operation cycle, and eliminates the need to turn off the laser during the entire welding operation, effectively extending the laser's lifespan.

[0050] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A 3D galvanometer flying laser welding method for welding battery cell terminals to busbars, characterized in that: The 3D vision module is used to obtain the three-dimensional position information of each cell terminal and busbar welding point. A 3D galvanometer is used to perform welding actions on each welding point based on the three-dimensional position information.

2. The 3D galvanometer flying laser welding method as described in claim 1, characterized in that: It features 3D precision measurement and 3D welding steps; The 3D precision measurement process involves a 3D vision module that flies at a constant speed along the busbar distribution direction and scans to obtain the three-dimensional position information of each cell terminal and busbar welding point. In the 3D welding process, the 3D galvanometer performs welding operations on each cell electrode and busbar based on the three-dimensional position information obtained from the 3D precision measurement process. The Z-axis height difference between different cell electrodes and busbars is adjusted by the Z-axis dynamic focusing module of the 3D galvanometer by shifting the focus point in the Z-axis.

3. The 3D galvanometer flying laser welding method as described in claim 2, characterized in that: Before the 3D precision measurement step, there is also a 2D coarse positioning step; In the 2D coarse positioning step, the 2D vision module moves to the top of the battery cell terminal and busbar to be welded, and identifies the position information of the busbar through the 2D camera of the 2D vision module. This position information provides the positioning basis for the 3D fine measurement step.

4. A 3D galvanometer flying laser welding system for welding busbars to cell terminals on a battery, characterized in that: It includes a frame and a robot, wherein Y-axis moving modules are distributed along the Y-axis on the frame, and X-axis moving modules are distributed on the Y-axis moving modules; The X-axis moving module is equipped with a 3D vision module and a copper nozzle pressing mechanism. The 3D vision module moves along the X-axis and scans to obtain the three-dimensional position information of the cell electrode and the busbar welding point. The copper nozzle pressing mechanism presses down against the busbar to be welded. The robot has an operating arm with a 3D galvanometer fixed on it. When the operating arm moves above a row of workpieces to be welded, it drives the 3D galvanometer to move along the X-axis and performs welding operations on the workpieces below.

5. The 3D galvanometer flying laser welding system as described in claim 4, characterized in that: After the robot's manipulator arm drives the 3D galvanometer to perform welding operations along the X-axis, it then drives the 3D galvanometer to move along the Y-axis to the next row of workpieces to be welded.

6. The 3D galvanometer flying laser welding system as described in claim 5, characterized in that: The robot's manipulator arm is equipped with a 2D vision module, which includes a 2D camera. The robot manipulator arm carries the 2D camera and moves horizontally along the X and Y directions to identify and locate the workpiece to be welded below.

7. The 3D galvanometer flying laser welding system as described in claim 6, characterized in that: The battery has several rows of workpieces to be welded, and there are positioning posts at the four corners of the battery. A 2D camera identifies the position information of the positioning posts, and the robot's manipulator adjusts its basic position in the X and Y directions according to the position information of the positioning posts.

8. The 3D galvanometer flying laser welding system as described in claim 4, characterized in that: The Y-axis movement module includes a Y-axis power mechanism and Y-axis guide rails symmetrically arranged on the frame. A Y-axis slider is slidably mounted on the Y-axis guide rail. The Y-axis power mechanism drives the Y-axis slider to slide along the Y-axis guide rail. A Z-axis slide rail is fixed on the Y-axis slider. A Z-axis power mechanism and a Z-axis slider are mounted on the Z-axis slide rail. The Z-axis slider moves along the Z-axis slide rail under the drive of the Z-axis power mechanism. The X-axis movement module is mounted on the corresponding Z-axis sliders on both sides.

9. The 3D galvanometer flying laser welding system as described in claim 8, characterized in that: The X-axis moving module includes an X-axis truss, a 3D vision module, and a copper nozzle pressing mechanism. A line scanning servo mechanism is slidably mounted on the X-axis truss. The 3D vision module is mounted on the line scanning servo mechanism and is driven by the line scanning servo mechanism to slide along the X-axis. The X-axis truss is also equipped with a copper nozzle pressing mechanism.

10. The 3D galvanometer flying laser welding system as described in claim 9, characterized in that: On the end face of the X-axis truss corresponding to the copper nozzle pressing mechanism, a servo copper nozzle moving mechanism is provided along the X-axis. The servo copper nozzle moving mechanism includes a copper nozzle guide rail and an X-axis servo mechanism. The X-axis servo mechanism drives the copper nozzle pressing mechanism to translate along the copper nozzle guide rail in the X-axis direction.

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