Robot end effector for welding in tight spaces

Abstract

The application relates to a robot end swing welding device for narrow space welding, which is characterized by setting an independent autonomous swing welding module at the robot end, the module being integrated with an independent driving mechanism and a micro welding gun, and the overall structure being compact. During welding operation, the robot body only needs to complete macro positioning and track movement, the compact swing welding module is sent to the vicinity of the narrow welding area, and then the independent driving mechanism of the module drives the micro welding gun to perform precise swing welding action in the narrow space. The structural design separates the complex swing welding function from the heavy end wrist of the robot body, fundamentally solves the accessibility problem that the existing general robot cannot stretch into the workpiece gap due to the oversized end effector and is prone to interference and collision, and ensures that the welding gun can complete the welding operation in the limited space in the correct posture.

Description

Technical Field

[0001] This application relates to the field of robotic automated welding technology, and in particular to a robotic end-effector for welding in confined spaces. Background Technology

[0002] In modern industrial manufacturing, automated welding has become a key technology for improving production efficiency, ensuring product quality, and improving the working environment. Industrial robots, with their high repeatability and stability, are widely used in welding operations in the automotive, shipbuilding, and construction machinery industries. However, for some workpieces with special and complex structures, such as the manifold-type workpieces commonly found in the chemical and energy fields, the structural characteristics are that multiple branch pipes are densely converged on the main pipe, and the gaps between the branch pipes are usually very narrow, with the minimum gap in some areas reaching 45mm or even smaller. Their welds are not simple planar curves, but rather exhibit a complex three-dimensional saddle-shaped trajectory.

[0003] Currently, the welding of such complex workpieces still mainly relies on highly skilled welders for manual operation. This method requires extremely high skill and experience from the welders, and the arc light, fumes and high temperatures generated during the welding process also pose a threat to the health of the operators.

[0004] In addition, there are also attempts to apply general-purpose six-axis industrial robots to such scenarios. However, the welding torches and end wrists of existing general-purpose welding robots are usually large in size and their structural design is not optimized for narrow spaces. As a result, when the robot approaches the weld seam, its end effector or arm will interfere with and collide with the workpiece itself, making it impossible to accurately deliver the tip of the welding torch and maintain it in the ideal welding posture. Utility Model Content

[0005] To address the aforementioned problems, this application provides a compact robotic end-effector for welding in confined spaces.

[0006] To achieve the above objectives, the robotic end effector for welding in confined spaces designed in this application includes: A connecting bracket, suitable for installation at the end of a robot; A swaying welding module is mounted on the connecting bracket. The swaying welding module includes a driving mechanism and a welding torch mounted on the driving mechanism. The driving mechanism is used to drive the welding torch to sway relative to the connecting bracket. The control unit is connected to the oscillating welding module and is used to control the drive mechanism to perform oscillating welding actions.

[0007] Preferably, the system further includes a vision acquisition module mounted on the connecting bracket for acquiring three-dimensional information of the area to be welded; wherein, the control unit is also signal-connected to the vision acquisition module and is used to control the oscillating welding module to perform oscillating welding actions based on the three-dimensional information.

[0008] Preferably, the drive mechanism of the oscillating welding module includes a rotating platform and a motor for driving the rotating platform to rotate, and the welding torch is fixed on the rotating platform.

[0009] Preferably, the rotating platform has a hollow channel through which the welding wire of the welding gun is adapted to pass.

[0010] Preferably, the motor is a stepper motor; the control unit controls the oscillation frequency and oscillation amplitude of the welding torch by controlling the rotation direction, speed and angle of the stepper motor.

[0011] Preferably, the diameter of the welding torch head is less than 30 mm.

[0012] Preferably, the connecting bracket includes a multi-degree-of-freedom adjustment structure for adapting to different robot models and adjusting the relative posture of the vision acquisition module and the welding module.

[0013] Preferably, the connecting bracket includes a first base and a second base suitable for installation on the end of a robot, the oscillating welding module is installed on the second base, the first base has a protruding eaves plate, the vision acquisition module is installed on the eaves plate and located above the oscillating welding module; wherein, the first base and the second base are pivotally connected to form the multi-degree-of-freedom adjustment structure.

[0014] Preferably, the first base and the second base are hollow to form an accommodating space, and the driving mechanism is accommodated within the accommodating space.

[0015] Preferably, the control unit is integrated into the robot control system or configured as a stand-alone controller.

[0016] The robotic end effector for welding in confined spaces designed in this application features an independent autonomous oscillating welding module at the robot's end effector. This module integrates an independent drive mechanism and a miniature welding torch, resulting in a compact overall structure. During welding operations, the robot body only needs to perform macroscopic positioning and trajectory movement to deliver this compact oscillating welding module to the vicinity of the narrow welding area. The module's independent drive mechanism then drives the miniature welding torch to perform precise oscillating welding movements within the confined space. This structural design removes the complex oscillating welding function from the cumbersome end effector of the robot body, fundamentally solving the accessibility problem of existing general-purpose robots where the large size of the end effector prevents it from reaching into workpiece gaps and easily leads to interference and collisions. This ensures that the welding torch can complete welding operations in confined spaces with the correct posture. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a robotic end-effector welding device for welding in confined spaces, provided in an embodiment of this application.

[0018] Figure 2 This is a schematic diagram of the motor arrangement provided in the embodiments of this application.

[0019] Figure 3 This is an installation schematic diagram of a robotic end-effector welding device for welding in confined spaces, provided in an embodiment of this application.

[0020] The components include: robot 100, connecting bracket 10, first base 11, second base 12, eaves 13, oscillating welding module 20, drive mechanism 30, rotating platform 31, motor 32, welding gun 40, welding wire 41, and vision acquisition module 50. Detailed Implementation

[0021] The preferred embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit this application.

[0022] Please see the appendix Figures 1 to 3 As shown, this application provides a robotic end effector for welding in confined spaces. Figure 3 As shown, in a specific application scenario, the device is installed on the end flange of an industrial robot 100 to perform automated welding operations on workpieces with complex structures and narrow spaces, such as manifolds.

[0023] like Figure 1 , Figure 2 As shown, the robot end effector welding device of this embodiment mainly includes a connecting bracket 10, a welding module 20, and a control unit not shown in the figure.

[0024] Specifically, the connecting bracket 10 serves as the base of the entire device, with one end connected to the end of the robot 100 via a standard interface such as a flange, for fixing the entire device onto the robot 100. In this embodiment, the connecting bracket 10 includes a first base 11 and a second base 12 pivotally connected to each other. This pivotal structure forms a multi-degree-of-freedom adjustment structure, allowing for fine-tuning of the initial posture of the welding module 20 during installation and commissioning, thereby enabling flexible adaptation to different models of the robot 100 and handling of different welding conditions.

[0025] The oscillating welding module 20 is mounted on the connecting bracket 10, specifically on the second base 12. The oscillating welding module 20 includes a drive mechanism 30 and a welding torch 40 mounted on the drive mechanism 30. The drive mechanism 30 is used to drive the welding torch 40 to oscillate relative to the connecting bracket 10.

[0026] The control unit is signal-connected to the oscillating welding module 20 and is used to control the drive mechanism 30 to perform oscillating welding actions. In specific implementations, the control unit is integrated into the robot 100 control system or configured as an independent controller, such as a stand-alone industrial computer.

[0027] In some embodiments, such as Figure 1 , Figure 2 As shown, the system also includes a vision acquisition module 50, which is mounted on the connecting bracket 10 and is used to acquire three-dimensional information of the area to be welded. The control unit is also signal-connected to the vision acquisition module 50 and is used to control the oscillating welding module 20 to perform oscillating welding actions based on the three-dimensional information. In this embodiment, the vision acquisition module 50 can be a three-dimensional vision sensor such as a point cloud camera, and its function is to acquire three-dimensional information of the area to be welded, such as three-dimensional point cloud data of the weld seam.

[0028] Before the welding operation begins, the robot 100 moves the device to the vicinity of the welding start point. The control unit activates the vision acquisition module 50 to scan the actual weld and obtain its three-dimensional point cloud data. Subsequently, based on the point cloud data, the control unit automatically generates a precise macroscopic welding path to guide the robot's movement through the built-in image processing and path planning algorithm, and can simultaneously plan the swing parameters at each point along the path.

[0029] During the welding process, the control unit performs coordinated control: on the one hand, based on the generated macroscopic welding path, it sends motion commands to the robot 100, driving the connecting bracket 10 to move smoothly along the weld seam trajectory; on the other hand, based on preset process requirements or path planning results, it sends control signals to the drive mechanism 30 of the oscillating welding module 20, driving the welding torch 40 to perform high-frequency oscillating motion. In specific implementation, such as... Figure 1As shown, the welding torch 40 can be, for example, an argon arc welding torch or a gas shielded welding torch, with a head diameter of less than 30 mm. This ensures that the welding torch can reach into narrow areas, such as the gap between manifold branches, without physical collision, thereby meeting process requirements.

[0030] In this way, the macroscopic trajectory tracking of the robot body and the microscopic oscillation of the welding torch are decoupled, enabling the device to adapt in real time to the actual position and shape deviations of the workpiece caused by clamping or manufacturing, thereby ensuring the welding accuracy and quality of complex welds in narrow spaces.

[0031] It should be noted that those skilled in the art will understand that the technology of automatically generating welding paths based on 3D point cloud data by the control unit is a mature existing technology. Specific algorithms, such as point cloud filtering, feature extraction, and curve fitting, can be implemented using well-known methods, or can be adaptively developed according to specific application requirements. Therefore, this application will not elaborate on their specific implementation details here.

[0032] In some embodiments, such as Figure 1 , Figure 2 As shown, the drive mechanism 30 of the oscillating welding module 20 includes a rotating platform 31 and a motor 32, which serves as a power source to drive the rotating platform 31 to rotate. The welding torch 40 is fixed to the rotating platform 31, specifically through a dedicated clamping structure, and moves as part of the platform. The output shaft of the motor 32 is connected to the rotating platform 31 via a coupling or gear transmission. When the control unit sends a command to the motor 32, the rotation of the motor 32 directly drives the rotating platform 31 and the welding torch 40 fixed on it to reciprocate in an angular oscillation.

[0033] In some embodiments, the rotating platform 31 has a hollow channel (not shown), through which the welding wire 41 of the welding torch 40 is adapted to pass. With this structural design, the cable and welding wire 41 of the welding torch 40 can be led out from the robot end effector and directly pass through this hollow channel before connecting to the welding torch 40, thus avoiding tangling of the cable and welding wire during the torch's oscillation, interference with the workpiece or the device itself, and making the overall structure more compact and neat.

[0034] In some embodiments, the motor 32 is a stepper motor, or it can be a DC motor. The control unit controls the stepper motor by sending a sequence of pulse signals to the stepper motor driver: the frequency of the pulses determines the speed of the stepper motor, i.e., the oscillation frequency of the welding torch, while the number of pulses determines the total rotation angle of the stepper motor, i.e., the oscillation amplitude of the welding torch, and the logical sequence of the pulses controls its rotation direction. Therefore, the oscillation frequency and oscillation amplitude required for the welding process can be conveniently and accurately set and adjusted through software programming to achieve digital and high-precision control of the oscillation parameters.

[0035] In some embodiments, such as Figure 1 , Figure 2 As shown, the connecting bracket 10 includes a first base 11 and a second base 12 adapted for mounting on the end of the robot 100. The first base 11 is used to connect to the end of the robot 100, and the second base 12 is used to mount the oscillating welding module 20. The first base 11 and the second base 12 are pivotally connected, for example, by a pin connection, forming a multi-degree-of-freedom adjustment structure. This structure allows adjustment of the angle of the second base 12 relative to the first base 11 during installation and debugging, thereby adjusting the initial posture of the entire oscillating welding module 20. Furthermore, the first base 11 also has an integrally formed or additionally fixed eaves plate 13 extending forward and upward. The vision acquisition module 50 is mounted on the eaves plate 13 and located diagonally above the oscillating welding module 20, providing it with the best field of view for observing the weld seam while avoiding mutual interference between the two.

[0036] In some embodiments, such as Figure 2 As shown, the first base 11 and the second base 12 are hollow to form an accommodating space, and the drive mechanism 30 is housed within the accommodating space. This structure encloses the motor 32, effectively preventing damage from spatter and fumes generated during welding, and improving the durability and reliability of the motor 32. Secondly, this structure effectively reduces the external outline dimensions of the device, avoiding interference that may be caused by exposed components, resulting in a compact structure.

[0037] The robotic end effector for welding in confined spaces provided in this application embodiment features an independent autonomous oscillating welding module at the robot's end effector. This module integrates an independent drive mechanism and a miniature welding torch, resulting in a compact overall structure. During welding operations, the robot body only needs to perform macroscopic positioning and trajectory movement to bring this compact oscillating welding module to the vicinity of the narrow welding area. Then, the module's independent drive mechanism drives the miniature welding torch to perform precise oscillating welding movements within the confined space. This structural design removes the complex oscillating welding function from the robot's bulky end effector wrist, fundamentally solving the accessibility problem of existing general-purpose robots where the large size of the end effector prevents it from reaching into workpiece gaps and easily leads to interference and collisions. This ensures that the welding torch can complete welding operations in confined spaces with the correct posture.

[0038] In the description of this application, it should be noted that the terms "vertical", "up", "down", "horizontal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0039] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0040] Finally, it should be noted that the above descriptions are merely preferred embodiments of this application and are not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A robot end swing welding device for welding in a narrow space, characterized by, include: A connecting bracket, suitable for installation at the end of a robot; A swaying welding module is mounted on the connecting bracket. The swaying welding module includes a driving mechanism and a welding torch mounted on the driving mechanism. The driving mechanism is used to drive the welding torch to sway relative to the connecting bracket. The control unit is connected to the oscillating welding module and is used to control the drive mechanism to perform oscillating welding actions.

2. The robot end effector weaving device for welding in tight spaces according to claim 1, wherein, It also includes a vision acquisition module, which is mounted on the connecting bracket and is used to acquire three-dimensional information of the area to be welded; wherein, the control unit is also signal-connected to the vision acquisition module and is used to control the oscillating welding module to perform oscillating welding actions according to the three-dimensional information.

3. The robot end effector welding device for welding in tight spaces of claim 1, wherein, The drive mechanism of the oscillating welding module includes a rotating platform and a motor for driving the rotating platform to rotate, and the welding torch is fixed on the rotating platform.

4. The robot end effector weaving device for welding in tight spaces of claim 3, wherein, The rotating platform has a hollow channel through which the welding wire of the welding gun is adapted to pass.

5. The robotic end effector for welding in confined spaces according to claim 3, characterized in that, The motor is a stepper motor; the control unit controls the oscillation frequency and oscillation amplitude of the welding torch by controlling the rotation direction, speed and angle of the stepper motor.

6. The robot end effector welding device for welding in tight spaces of claim 1, wherein, The diameter of the welding torch head is less than 30mm.

7. The robot end effector welding device for welding in tight spaces of claim 2, wherein, The connecting bracket includes a multi-degree-of-freedom adjustment structure for adapting to different robot models and adjusting the relative posture of the vision acquisition module and the welding module.

8. The robot end effector welding device for welding in tight spaces of claim 7, wherein, The connecting bracket includes a first base and a second base suitable for installation at the end of a robot. The oscillating welding module is installed on the second base. An eaves plate is protruding from the first base. The vision acquisition module is installed on the eaves plate and located above the oscillating welding module. The first base and the second base are pivotally connected to form the multi-degree-of-freedom adjustment structure.

9. The robot end effector welding device for welding in tight spaces of claim 8, wherein, The first base and the second base are hollow to form an accommodating space, and the driving mechanism is accommodated in the accommodating space.

10. The robot end effector welding device for welding in tight spaces of claim 1, wherein, The control unit is integrated into the robot control system or configured as a standalone controller.

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