A laser brazing method and system for vertical welding position
By dynamically matching laser brazing process parameters within the vertical welding angle range, the problem of uneven weld quality at the vertical welding position was solved, achieving the formation of high-quality and stable welds and automated welding, thus expanding the application of laser brazing technology in complex vehicle body structures.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ANHUI JEE AUTOMATION EQUIP CO LTD
- Filing Date
- 2026-02-28
- Publication Date
- 2026-05-29
AI Technical Summary
Existing laser brazing technology, when used in vertical welding positions, struggles to dynamically match optimal process parameters based on real-time changes in the welding angle, resulting in poor weld quality stability. This is particularly problematic in complex vehicle body structures, where issues such as filler metal flow and uneven weld formation quality arise.
By dividing the vertical welding angle into multiple preset intervals and matching each interval with a specific combination of laser brazing process parameters, including laser power, wire feed speed and spot parameters, the controller dynamically adjusts these parameters in real time or in intervals to achieve automation of the welding process and adaptive matching of parameters.
Within a wide angle range of 0° to 60°, uniform weld formation and excellent sealing performance are achieved, significantly improving the level of welding automation and process adaptability, and overcoming the shortcomings of traditional process parameters that cannot adapt to angle changes.
Smart Images
Figure CN122099467A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of laser brazing technology, and in particular to a laser brazing method and system for vertical welding positions. Background Technology
[0002] Laser brazing technology, due to its advantages such as high energy density, fast heating speed, small heat-affected zone, and minimal welding deformation, has been widely used in the field of precision joining of metal materials, especially in automobile body manufacturing. It is commonly used for joining parts such as roof panels, side panels, tailgates, and drainage channels. Currently, mature laser brazing processes in industrial applications are mostly optimized for flat welds or small-angle inclined welds. Their process parameters (such as laser power, wire feed speed, and spot characteristics) ensure stable melting and spreading of the brazing filler metal in these positions, resulting in a high-quality weld.
[0003] However, in the manufacturing of complex vehicle body structures (such as side panels, pillars, and doors), there are numerous weld locations that require vertical or steeply angled upward welding. When the welding position changes from flat welding to vertical welding, the molten filler metal is prone to flowing downwards under the influence of gravity (i.e., "drooling"), resulting in insufficient filler metal filling at the upper part of the weld, forming undercut or incomplete penetration, while the filler metal accumulates at the lower part, forming weld beads. This severely impairs the weld's forming quality, sealing performance, and the uniformity of its mechanical properties.
[0004] To address the aforementioned issues, some improvements have been implemented in existing technologies, such as reducing wire feed speed or adjusting laser power to attempt to suppress brazing filler metal flow. However, most of these solutions are based on static parameter optimization for a single angle, or only make local adjustments for a specific vertical welding angle. When the welding angle varies continuously within the range of 0° to 60°, traditional static process parameter combinations are difficult to achieve global adaptation: if the parameter settings are biased towards small angles, brazing filler metal flow will be severe during welding at large angles; if the parameter settings are biased towards large angles, overheating and spattering may occur during welding at small angles. Therefore, existing technologies lack a laser brazing method that can dynamically match the optimal process parameter combination according to the real-time changes in the vertical welding angle, resulting in poor weld quality stability and insufficient process adaptability at vertical welding positions, which restricts the widespread application of laser brazing technology in welding complex spatial structures. Summary of the Invention
[0005] The purpose of this invention is to overcome the shortcomings of the prior art. To achieve the above objective, a laser brazing method and system for vertical welding positions are adopted to solve the problems mentioned in the background art.
[0006] A laser brazing method for vertical welding positions includes the following steps:
[0007] Determine the vertical welding angle of the weld seam on the workpiece to be welded; Based on the preset angle range to which the vertical welding angle belongs, a corresponding combination of laser brazing process parameters is selected. The process parameters include at least laser power, wire feed speed and laser spot parameters, and the combination of process parameters is different for different angle ranges. The workpiece to be welded is laser brazed using the selected combination of process parameters.
[0008] As a further aspect of the present invention: the vertical welding angle is 0°≤ i ≤60°; wherein, the vertical welding angle range of 0° to 60° is pre-divided into at least two consecutive angle intervals, and each angle interval is associated with a set of optimized process parameter combinations.
[0009] As a further aspect of the present invention: the laser power and / or wire feed speed in the process parameter combination vary with the vertical welding angle. i The increase corresponds to the increase in the value.
[0010] As a further aspect of the present invention: the angle interval includes a first angle interval, a second angle interval, a third angle interval, and a fourth angle interval.
[0011] As a further aspect of the present invention: the laser brazing is completed by driving an end effector that integrates a laser welding head and a wire feeding mechanism to move in coordination; the laser welding head and the laser are connected by an optical fiber and are coordinated and controlled by a controller.
[0012] As a further aspect of the present invention: the vertical welding angle i The angle of inclination of the weld relative to the horizontal plane, including vertical upward welding and vertical downward welding.
[0013] As a further aspect of the present invention: based on the vertical welding angle i The output power of the laser and the wire feeding speed of the wire feeding mechanism are dynamically adjusted in real time or in intervals according to the changes.
[0014] As a further aspect of the present invention: a protective gas is supplied to the molten pool area during the welding process.
[0015] The second aspect of the technical solution: a brazing system employing a laser brazing method for vertical welding positions as described in any of the above claims, comprising: Robots are used to drive the movement of end effectors; Laser, used to generate laser light; A laser welding head, mounted on the end effector of the robot, is used to focus the laser onto the workpiece; The wire feeding mechanism is used to feed brazing wire into the molten weld pool. Adjustable vertical welding fixture, used to clamp and adjust the workpiece to be welded to the required vertical welding angle; The controller is communicatively connected to the robot, laser, laser welding head, and wire feeding mechanism, and has pre-stored combinations of process parameters corresponding to different vertical welding angle ranges; the controller is configured as follows: Receive or calculate the vertical welding angle of the current weld. i ; According to the vertical welding angle i The corresponding combination of process parameters will be automatically called based on the given angle range. The robot, laser, and wire feeding mechanism are controlled to operate in coordination with the called parameter combination to complete the welding.
[0016] As a further aspect of the present invention: the laser welding head is a special welding head for laser filler wire welding, which can adjust the shape and position of the laser spot.
[0017] Compared with the prior art, the present invention has the following technical advantages: The above-described technical solution identifies the spatial angle of the weld seam to be welded (within the range of 0° to 60°); then, based on the preset interval to which this angle belongs, it automatically matches and calls a set of specific laser brazing process parameters (such as laser power, wire feed speed, etc.), with different parameter combinations corresponding to different intervals; finally, welding is performed using this parameter combination. This method, through a dynamic "angle-parameter" matching mechanism, effectively overcomes the problems of filler metal flow (drooling) caused by gravity during vertical welding in traditional laser brazing, as well as the inability of static parameters to adapt to angle changes. This achieves high-quality, stable weld seams with uniform formation and excellent sealing performance across a wide range of vertical welding angles, significantly improving the level of welding automation and process adaptability. Attached Figure Description
[0018] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the steps of the laser brazing method disclosed in this application. Figure 2 This is a schematic diagram of the structure of the test plate according to an embodiment of this application; Figure 3 This is a schematic diagram of the weld seam of the plate material according to an embodiment of this application. Detailed Implementation
[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0020] Please refer to Figure 1 In this embodiment of the invention, a laser brazing method for vertical welding positions includes the following steps: Step S1: Determine the vertical welding angle of the weld seam on the workpiece to be welded; Step S2: Select the corresponding combination of laser brazing process parameters according to the preset angle range to which the vertical welding angle belongs. The process parameters include at least laser power, wire feed speed and laser spot parameters, and the combination of process parameters is different for different angle ranges. In this embodiment, the vertical welding angle is 0°≤ i ≤60°; wherein, the vertical welding angle range of 0° to 60° is pre-divided into at least two consecutive angle intervals, and each angle interval is associated with a set of optimized process parameter combinations.
[0021] In this embodiment, the laser power and / or wire feed speed in the process parameter combination vary with the vertical welding angle. i The increase corresponds to the increase in the value.
[0022] In this embodiment, the angle range includes a first angle range corresponding to horizontal welding, a second angle range corresponding to small-angle vertical welding, a third angle range corresponding to medium-angle vertical welding, and a fourth angle range corresponding to large-angle vertical welding; wherein, the first range corresponds to i =0°, the second interval corresponds to 0°< i ≤30°, the third interval corresponds to 30°< i ≤45°, the fourth interval corresponds to 45°< i ≤60°.
[0023] In this embodiment, the laser brazing is completed by an industrial robot driving an end effector that integrates a laser welding head and a wire feeding mechanism to move in coordination; the laser welding head is connected to the laser via optical fiber and is coordinated and controlled by a controller.
[0024] In this embodiment, the vertical welding angle i The angle of inclination of the weld relative to the horizontal plane, including vertical upward welding and vertical downward welding.
[0025] In this embodiment, based on the vertical welding angle i The output power of the laser and the wire feeding speed of the wire feeding mechanism are dynamically adjusted in real time or in intervals according to the changes.
[0026] In this embodiment, a protective gas is supplied to the molten pool area during the welding process.
[0027] Step S3: Using the selected combination of process parameters, perform laser brazing on the workpiece to be welded.
[0028] The second aspect of the technical solution: a brazing system employing a laser brazing method for vertical welding positions as described in any of the above claims, comprising: Robots are used to drive the movement of end effectors; Laser, used to generate laser light; A laser welding head, mounted on the end effector of the robot, is used to focus the laser onto the workpiece; The wire feeding mechanism is used to feed brazing wire into the molten weld pool. Adjustable vertical welding fixture, used to clamp and adjust the workpiece to be welded to the required vertical welding angle; The controller is communicatively connected to the robot, laser, laser welding head, and wire feeding mechanism, and has pre-stored combinations of process parameters corresponding to different vertical welding angle ranges; the controller is configured as follows: Receive or calculate the vertical welding angle of the current weld. i ; According to the vertical welding angle i The corresponding combination of process parameters will be automatically called based on the given angle range. The robot, laser, and wire feeding mechanism are controlled to operate in coordination with the called parameter combination to complete the welding.
[0029] like Figure 3 As shown, the diagram illustrates the weld seam of the plate. Among them, (1) data acquisition Real-time data acquisition by the robot control system: Coordinates of weld feature points (such as the center point of the butt joint groove) under the base coordinate system ; Coordinates of the laser head TCP point under tool coordinates and laser head attitude angle ; The sampling frequency is synchronized with the robot's movement (≥50Hz) to ensure real-time performance.
[0030] (2) Angle calculation logic (core formula) Taking a vertical welding scenario as an example, calculate the angle between the weld axis and the vertical direction (base coordinate Z-axis). : Extract the direction vector of the weld in the base coordinate system:
[0031] in The starting point of the weld. This marks the end point of the weld. Vertical unit vector:
[0032] Vertical welding angle of weld:
[0033] The result range is 0° to 90°, with 90° being a pure vertical weld.
[0034] (3) Angle verification (optional, to improve accuracy) Combining the laser head attitude angle α (the angle between the laser head and the weld surface) with the tool coordinates, for Make compensation corrections:
[0035] Where k is the compensation coefficient for process calibration, with a value of 0.05 to 0.1.
[0036] In this embodiment, the laser welding head is a special welding head for laser filler wire welding, which can adjust the shape and position of the laser spot.
[0037] In this embodiment, the specific implementation steps are as follows: 1. Experimental preparation and environmental setup This embodiment was conducted on an automated laser brazing experimental platform. The core hardware of this platform includes: an industrial robot, a fiber laser (maximum power 6000W), a laser welding head (optical ratio 1.0), a push-pull wire feeder, and a controller. The laser is connected to the welding head via a 600μm core diameter optical fiber. The welding material is 1.0mm diameter CuSi3 welding wire, and the shielding gas is 99.99% pure argon.
[0038] 2. Workpieces to be welded and their pretreatment like Figure 2 As shown in the diagram, the workpiece consists of two galvanized steel sheets, each 1 mm thick and measuring 500 mm (length) × 150 mm (width). The two sheets are joined at an angle (one on top of the other, forming a lap weld). Before welding, the surfaces of the areas to be welded on both sheets are thoroughly wiped with anhydrous alcohol to remove oil and other impurities.
[0039] 3. Workpiece clamping and angle setting After cleaning, the upper and lower plates are stacked alternately according to the design requirements and placed on the experimental platform. Then, a set of dedicated adjustable vertical welding fixtures is used to fix the assembly. By adjusting this fixture, the entire plate, along with the weld seam to be welded, can be tilted at any desired angle within the range of 0° to 60°, simulating the vertical welding position in actual production. This embodiment requires the fixture positioning error to be ≤0.2mm and the plate tilt angle setting deviation to be ≤0.5°.
[0040] 4. Implementation of Angle-Parameter Adaptive Matching Mechanism The core of this invention lies in the preset angle-parameter matching database within the controller. This database divides the vertical welding angle θ from 0° to 60° into four consecutive intervals, and stores a set of coordinated parameter combinations optimized through extensive process experiments for each interval to suppress solder flow. The division is based on the inflection point of significant change in the influence of gravity on the molten pool behavior: The first interval (θ≈0°) is considered as the reference for flat welding.
[0041] Second interval (0°<θ≤30°): The effects of gravity begin to appear.
[0042] In the third interval (30°<θ≤45°): gravity has a significant effect.
[0043] The fourth interval (45°<θ≤60°): the influence of gravity is the most severe.
[0044] Once the workpiece is clamped, the system automatically identifies the current vertical welding angle θ (e.g., 30°) of the weld seam using tooling sensors or the robot coordinate system. The controller then automatically calls up the complete set of process parameters corresponding to the interval to which θ belongs (the second interval) and issues instructions to the laser, wire feeder, and other actuators. The specific collaborative parameters for each interval verified in this embodiment are shown in the table below:
[0045] 5. Welding execution and process control After the parameters are automatically set, the welding program is started. The robot moves along a predetermined trajectory (along the lap joint), driving the laser welding head and wire feeder to move in tandem. During the process, the laser outputs the set power, and the wire feeder synchronously pushes the CuSi3 welding wire into the molten pool at the set speed. The entire welding process is centrally monitored and controlled by the controller, requiring no manual intervention for parameter adjustment.
[0046] 6. Post-weld treatment After the welding trajectory is completed, the protective gas (argon) continues to be sprayed for 5-8 seconds until the weld pool is completely solidified, thereby preventing oxidation of the high-temperature weld.
[0047] 7. Implementation Results Using the above method, welding was performed at four representative vertical welding angles: 0°, 30°, 45°, and 60°. The results show that the welds at all angles are continuous, uniform, and smooth, effectively overcoming the "drooling" phenomenon caused by gravity in the molten brazing filler metal. The welds exhibit no undercut at the top and no weld beads at the bottom, demonstrating good consistency in sealing and mechanical properties. This verifies the effectiveness and superiority of the angle-parameter adaptive matching method of this invention.
[0048] It is understandable that, based on the optimized parameters of the above discrete angle points, those skilled in the art can fit or derive the optimal process parameters corresponding to any vertical welding angle within the same range through limited conventional experiments, without having to put in any creative effort.
[0049] The beneficial effects of this invention are mainly reflected in the following aspects: 1. Effectively overcomes the influence of gravity, achieving high-quality vertical welding: Addressing the core challenge of poor weld quality caused by molten filler metal flowing due to gravity in traditional laser brazing at vertical welding positions, this invention establishes a dynamic matching relationship between the vertical welding angle and key process parameters (such as laser power and wire feed speed), achieving precise control over filler metal flow behavior. This ensures that within a wide angle range of 0° to 60°, uniformly formed welds with no undercut, no weld beads, and a smooth, continuous surface can be obtained, significantly improving the sealing reliability and mechanical property consistency of the joint.
[0050] 2. Overcoming the limitations of process angular adaptability and expanding application scope: By dividing the continuous vertical welding angle space into multiple intervals based on gravity influence characteristics, and matching each interval with a collaboratively optimized parameter combination, this invention breaks the limitation that traditional process parameters are only applicable to fixed or small-angle welding. This allows the same system and process to be stably adapted to vertical welds in various complex spatial positions in vehicle body manufacturing, greatly enhancing the process flexibility and application breadth of laser brazing technology.
[0051] 3. Enhanced automation and intelligence in the welding process: Relying on an integrated control system, this invention achieves full automation from angle recognition and automatic parameter matching to welding execution. This "angle-parameter" adaptive mechanism significantly reduces reliance on operator experience, minimizes debugging time and human intervention, and not only greatly improves production efficiency and process stability, but also makes this technology particularly suitable for high-cycle, high-consistency automated production lines, effectively reducing overall production costs.
[0052] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention. The scope of the invention is defined by the appended claims and their equivalents, all of which should be included within the scope of protection of the invention.
Claims
1. A laser brazing method for vertical welding positions, characterized in that, Includes the following steps: Determine the vertical welding angle of the weld seam on the workpiece to be welded; Based on the preset angle range to which the vertical welding angle belongs, a corresponding combination of laser brazing process parameters is selected. The process parameters include at least laser power, wire feed speed and laser spot parameters, and the combination of process parameters is different for different angle ranges. The workpiece to be welded is laser brazed using the selected combination of process parameters.
2. The laser brazing method for vertical welding positions according to claim 1, characterized in that, The vertical welding angle is 0°≤ θ ≤60°; wherein, the vertical welding angle range of 0° to 60° is pre-divided into at least two consecutive angle intervals, and each angle interval is associated with a set of optimized process parameter combinations.
3. The laser brazing method for vertical welding positions according to claim 2, characterized in that, The laser power and / or wire feed speed in the process parameter combination vary with the vertical welding angle. θ The increase corresponds to the increase in the value.
4. The laser brazing method for vertical welding positions according to claim 3, characterized in that, The angle range includes a first angle range, a second angle range, a third angle range, and a fourth angle range.
5. The laser brazing method for vertical welding positions according to claim 4, characterized in that, The laser brazing is completed by driving an end effector that integrates a laser welding head and a wire feeding mechanism to move in coordination; the laser welding head is connected to the laser via an optical fiber and is coordinated and controlled by a controller.
6. The laser brazing method for vertical welding positions according to claim 5, characterized in that, The vertical welding angle θ The angle of inclination of the weld relative to the horizontal plane, including vertical upward welding and vertical downward welding.
7. The laser brazing method for vertical welding positions according to claim 6, characterized in that, According to the vertical welding angle θ The output power of the laser and the wire feeding speed of the wire feeding mechanism are dynamically adjusted in real time or in intervals according to the changes.
8. The laser brazing method for vertical welding positions according to claim 1, characterized in that, During the welding process, protective gas is supplied to the molten pool area.
9. A brazing system employing a laser brazing method for a vertical welding position as described in any one of claims 1 to 8, characterized in that, include: Robots are used to drive the movement of end effectors; Laser, used to generate laser light; A laser welding head, mounted on the end effector of the robot, is used to focus the laser onto the workpiece; The wire feeding mechanism is used to feed brazing wire into the molten weld pool. Adjustable vertical welding fixture, used to clamp and adjust the workpiece to be welded to the required vertical welding angle; The controller is communicatively connected to the robot, laser, laser welding head, and wire feeding mechanism, and has pre-stored combinations of process parameters corresponding to different vertical welding angle ranges; the controller is configured as follows: Receive or calculate the vertical welding angle of the current weld. θ ; According to the vertical welding angle θ The corresponding combination of process parameters will be automatically called based on the given angle range. The robot, laser, and wire feeding mechanism are controlled to operate in coordination with the called parameter combination to complete the welding.
10. The laser brazing method for vertical welding positions according to claim 1, characterized in that, The laser welding head is a special welding head for laser filler wire welding, which can adjust the shape and position of the laser spot.