A robotic arm welding apparatus

Abstract

The application discloses a mechanical arm welding device, and belongs to the technical field of laser welding devices.The mechanical arm welding device comprises a mechanical arm mechanism and a laser welding mechanism.A protective lens and a nozzle are arranged in a vertical cylinder of the laser welding mechanism.A cleaning unit and a protective gas unit are arranged between the protective lens and the nozzle.The cleaning unit comprises an annular air ring seat, and air blowing ports and air suction ports corresponding to the protective lens are arranged on the air ring seat.The air blowing ports and the air suction ports are respectively connected with a gas supply component and an exhaust component.The gas supply component sprays clean gas to the surface of the protective lens to form a flowing protective gas film, and the exhaust component directs the gas and pollutants to be discharged.The air ring seat can be driven by a rotary driving assembly to rotate around an axis, so that the protective lens is cleaned without any dead angle around the whole circumference.The active cleaning structure with the blowing and suction integrated together can effectively block welding splashes and smoke dust from eroding the protective lens, greatly prolongs the service life of consumables, does not interfere with the main protective gas flow field, is suitable for multi-posture welding working conditions, and improves the production efficiency of the device.

Description

Technical Field

[0001] This invention relates to the field of laser welding equipment technology, and in particular to a robotic arm welding device. Background Technology

[0002] Robotic arm welding equipment is an integrated industrial equipment that combines robotics technology, welding processes, and automated control. It uses a welding torch and other actuators mounted on the end flange of a multi-degree-of-freedom robotic arm. A programmable control system precisely controls the welding torch to automatically complete the welding task according to a preset trajectory and welding process parameters. Among these, fiber laser welding heads, as commonly used end-effectors in welding robotic arms, are widely used in automated welding production scenarios such as new energy, precision hardware, and medical devices due to their advantages of high energy density, low welding thermal deformation, and high welding speed.

[0003] In existing technologies, laser welding heads typically employ a horizontal light-inlet, beam-splitter-deflected, vertical light-outlet optical path layout. This allows for the integration of coaxial vision positioning and molten pool monitoring modules, enabling weld seam location and process monitoring, and is suitable for high-precision automated welding operations. This type of welding head utilizes a graded chamber sealing structure, with a collimating lens group, beam splitter, focusing lens group, and protective lens arranged sequentially along the optical path. The protective lens acts as a sacrificial shielding element to isolate upstream precision optical components. Simultaneously, a coaxial protective gas outlet is provided at the nozzle, relying on the forward airflow at the outlet to block welding impurities and protect the molten pool. This is currently the mainstream structural solution in the industry.

[0004] However, in actual continuous industrial production, the keyhole effect of laser deep penetration welding generates high-temperature, high-pressure metal vapor inside the molten pool, accompanied by a large number of molten spatter particles. Among them, large-sized spatter possesses extremely high initial kinetic energy, and its inertial force is far greater than the resistance force of the shielding gas flow, allowing it to penetrate the shielding gas layer in reverse and directly impact the surface of the protective lens. The high-speed metal vapor jet ejected from the keyhole also disturbs the flow field structure at the nozzle exit, forming a local instantaneous reverse transport channel that pushes metal vapor and fine particles into the nozzle cavity, where they condense and deposit upon encountering the low-temperature lens. At the same time, during the transient stages of arc initiation and arc termination, the shielding gas flow has not yet established a stable flow field or has already begun to decay, creating a gap in the protection sequence. Explosive spatter and residual high-temperature vapor can easily enter the cavity under these circumstances. For submicron-sized ultrafine condensed dust, the thermophoretic force generated by the temperature gradient drives the particles to continuously migrate and deposit on the lower-temperature surface of the protective lens. This process is not affected by the airflow direction, and long-term accumulation will also cause lens contamination. In addition, robotic arm welding equipment needs to be adapted to various working conditions such as vertical welding, overhead welding, and inclined welding of spatial curved surfaces. The protective airflow is deflected and distorted by gravity, and the protective capability of the airflow weak area is significantly reduced, further aggravating the risk of impurity intrusion.

[0005] Therefore, based on the above reasons, even if the laser beam path and the shielding gas outlet are coaxially aligned in existing laser welding heads, the positive pressure at the outlet formed by the coaxial shielding gas at the nozzle still cannot completely block metal spatter, metal vapor, and ultrafine welding fumes. Impurities will still concentrate and contaminate the central optical path area of ​​the protective lens, resulting not only in rapid consumption of protective lens materials and low material utilization, but also in laser power attenuation and thermal lensing effects, leading to insufficient weld penetration and poor forming consistency. If the fumes continue to penetrate upwards and contaminate high-value components such as focusing lenses and beam splitters, it will also cause blurred coaxial visual imaging and reduced weld seam positioning accuracy. Furthermore, the upstream optical component disassembly, cleaning, and optical path calibration processes are complex and have high maintenance costs, severely reducing the production uptime of the equipment. Summary of the Invention

[0006] The main objective of this invention is to provide a robotic arm welding device that integrates a blow-suction cleaning unit and an optimized protective gas unit under the protective lens to achieve active gas film protection and real-time cleaning of the protective lens, thereby improving the reliability of the protection system, extending the service life of consumables, reducing equipment operation and maintenance costs, and increasing production utilization.

[0007] To achieve the above objectives, the present invention proposes a robotic arm welding device, including a robotic arm mechanism and a laser welding mechanism connected to the robotic arm mechanism. The laser welding mechanism includes a vertical cylinder with a nozzle at one end, and a protective lens is disposed inside the vertical cylinder. It also includes a cleaning unit and a protective gas unit disposed between the protective lens and the nozzle. The protective gas unit is used to spray protective gas outward through the nozzle. The cleaning unit includes an air ring seat disposed within a vertical cylinder. The air ring seat has an annular structure and is located below the periphery of the protective lens. The air ring seat is provided with an air blowing port and an air intake port corresponding to the protective lens. The air blowing port and the air intake port are symmetrically arranged on the air ring seat and are respectively connected to an air supply component and an air exhaust component. The air supply component is connected to the air blowing port and is used to spray clean gas onto the surface of the protective lens through the air blowing port to form a flowing air film on the surface of the protective lens. The air exhaust component is connected to the air intake port and is used to guide the gas at the protective lens outward through the air intake port and discharge it to the outside.

[0008] In one possible implementation, the air ring seat is rotatably assembled into the vertical cylinder, and a rotation drive assembly is provided between the air ring seat and the vertical cylinder. The rotation drive assembly is used to drive the air ring seat to rotate along the center of the protective lens within the vertical cylinder. It also includes a transmission structure provided between the air ring seat and the air supply component and the air exhaust component. The transmission structure is used to ensure that the air supply component and the air exhaust component are always connected to the air blowing port and the air intake port when the air ring seat rotates.

[0009] In one possible implementation, the air ring seat is composed of a first ring seat and a second ring seat, the first ring seat and the second ring seat are coaxially arranged and linked to each other to achieve synchronous rotation; the air blowing port is arranged on the first ring seat and the air intake port is arranged on the second ring seat; the transmission structure includes a first transmission component arranged between the first ring seat and the air supply component, and a second transmission component arranged between the second ring seat and the exhaust component.

[0010] In one possible implementation, the air ring seat further includes a guide ring seat fixedly disposed within the vertical cylinder. The guide ring seat has a guide opening at its top that is obliquely disposed relative to the surface of the protective lens, and a rotating groove at its bottom that communicates with the guide opening. The tops of the first ring seat and the second ring seat both have protruding extensions. The extensions are arc-shaped and coaxial with the guide ring seats, with their ends extending into the rotating groove and rotatable along the rotating groove. The air blowing port and the air suction port are respectively disposed at the ends of the extensions located in the rotating groove.

[0011] In one possible implementation, the outer circumference of the first ring seat is recessed inward to form a fitting ring groove, and the second ring seat is sleeved in the fitting ring groove to achieve coaxial arrangement with the first ring seat; the extension of the second ring seat abuts against the top of the first ring seat and can be spliced ​​with the extension of the first ring seat to form a ring structure.

[0012] In one possible implementation, both the first transmission assembly and the second transmission assembly include a transfer air chamber disposed around the first ring seat and the second ring seat, the transfer air chamber being connected to an air intake or an air blowing port; and further include a sealing ring strip rotatably disposed at the opening of the transfer air chamber, the sealing ring strip having a connecting pipe connected to an air supply component or an air exhaust component.

[0013] In one possible implementation, an airflow channel is provided between the air supply component and the air outlet on the first ring seat. The airflow channel is located on the vertical cylinder and includes a distribution pipe disposed inside the vertical cylinder and located around the first ring seat. It also includes a first air chamber disposed inside the first ring seat and connected to the air outlet. The first air chamber is connected to a transfer air chamber on the first ring seat, and the distribution pipe is connected to the transfer air chamber on the first ring seat through a corresponding connecting pipe.

[0014] In one possible implementation, the rotary drive assembly includes a drive ring groove disposed around the periphery of the first ring seat, with a plurality of obliquely arranged blades fixedly disposed on the inner wall of the drive ring groove; it also includes a pressurizing chamber disposed in a vertical cylinder and communicating with a distribution pipe, the pressurizing chamber being disposed around the drive ring groove, and the inner wall of the vertical cylinder being provided with a plurality of air jet holes communicating with the pressurizing chamber, the plurality of air jet holes being disposed toward the blades, for driving the first ring seat to rotate by blowing the blades.

[0015] In one possible implementation, the vertical cylinder is provided with an exhaust channel corresponding to the position of the transfer chamber on the second ring seat, and the exhaust channel is used to connect the exhaust component with the transfer chamber on the second ring seat.

[0016] In one possible implementation, the protective gas unit includes a guide ring plate disposed on the inner wall of the vertical cylinder. The guide ring plate has a U-shaped structure with an open bottom and a connection hole on its inner wall that connects to the gas delivery component. It also includes a guide pipe disposed in the vertical cylinder and located at the nozzle. The guide pipe is hollow and has several guide holes on its upper part facing the nozzle. The vertical cylinder has a gas passage that connects the connection hole and the guide pipe.

[0017] Compared with the prior art, the beneficial effects of this application are as follows: This invention features an annular air ring seat with both an air blowing port and an air suction port located below the protective lens. Clean gas is sprayed onto the surface of the protective lens by an air supply component to form a flowing protective air film. This film can block welding spatter and metal vapor from directly impacting and condensing on the lens surface, thus reducing the impact of high-energy particles. Furthermore, it can continuously clean the lens surface, promptly removing ultrafine fumes deposited by thermophoresis. This transforms passive protection into active cleaning, significantly extending the service life of the protective lens and reducing the frequency and cost of consumable replacement.

[0018] Simultaneously, the exhaust components draw in gas, directing the purged gas and entrained contaminants out of the equipment to prevent secondary diffusion of contaminants within the cavity, prevent upstream penetration of contaminants, and avoid downward flow of clean gas interfering with the main protective gas flow field, thus ensuring the stability of the welding process.

[0019] The symmetrically arranged air inlets and outlets create a localized directional airflow, preventing contaminants from spreading towards the nozzle and ensuring that the protective gas unit's effect on the molten pool remains undisturbed. As the gas ring seat rotates, the blowing and suction action covers the entire surface of the protective lens, eliminating cleaning dead zones. This is particularly suitable for multi-position welding operations by robotic arms, improving the consistency of protection. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0021] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a structural diagram showing the connection between the robotic arm mechanism and the laser welding mechanism. Figure 3 This is a three-dimensional view of the laser welding mechanism structure in this invention; Figure 4 This is a cross-sectional view of the laser welding mechanism of the present invention; Figure 5 This is an exploded view of the cleaning unit in this invention; Figure 6 This is a structural diagram of the protective lens in this invention; Figure 7 for Figure 4 Enlarged view of the protective gas unit at point A; Figure 8 This is a structural diagram of the gas ring seat in this invention; Figure 9 This is a cross-sectional view of the cleaning unit in this invention; Figure 10 for Figure 9 Enlarged view of point B in the middle.

[0022] Explanation of icon numbers: 1. Robotic arm mechanism; 10. End flange; 2. Laser welding mechanism; 21. Horizontal cylinder; 22. Vertical cylinder; 23. Nozzle; 24. Protective lens; 25. Beam splitter; 26. Collimation unit; 27. Coaxial vision unit; 28. Focusing lens group; 3. Cleaning unit; 31. Air ring seat; 311. First ring seat; 312. Second ring seat; 313. Air outlet; 314. Air inlet; 315. Extension; 316. Fitting ring groove; 32. Air supply pipe; 33. Exhaust pipe; 34. Rotary drive assembly; 341. Drive ring groove; 342. Blade; 343. Pressurization chamber; 344. Air jet hole; 35. Transmission structure; 351, transfer air chamber; 352, sealing ring; 353, connecting pipe; 36, guide ring seat; 361, guide port; 362, rotating groove; 37, airflow channel; 371, distribution pipe; 372, first air chamber; 38, exhaust port; 4, protective gas unit; 41, guide ring plate; 42, connecting hole; 43, guide pipe; 44, guide hole; 45, air passage; 51, focusing lens mounting section; 52, lens mounting section; 53, cleaning mounting section; 54, protective gas mounting section; 55, nozzle connecting section; 61, drawer seat; 62, lens pressure ring; 63, buffer ring; 65, locking screw.

[0023] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0025] Reference Figures 1 to 10 As shown in the figure, the robotic arm welding equipment described in this embodiment is as follows: Figures 1 to 2 As shown, the system includes a robotic arm mechanism 1 and a laser welding mechanism 2 connected to the end flange 10 of the robotic arm mechanism 1. The robotic arm mechanism 1 is a six-degree-of-freedom industrial robot that can drive the laser welding mechanism 2 to complete welding operations in any posture within space. This is a mature existing technology in the field, and its specific structure will not be described in detail in this embodiment.

[0026] like Figures 3 to 4 As shown, the laser welding mechanism 2 is a right-angle bend fiber laser welding head, comprising a horizontal cylinder 21 and a vertical cylinder 22 that are perpendicularly connected to each other. A collimation unit 26 is installed inside the horizontal cylinder 21. A beam splitter 25 is installed at the corner connecting the horizontal cylinder 21 and the vertical cylinder 22. A coaxial vision unit 27 is installed at the top of the vertical cylinder 22. A focusing lens group 28 and a protective lens 24 are sequentially arranged from top to bottom along the optical path inside the vertical cylinder 22. A nozzle 23 is installed at the lower end of the vertical cylinder 22. The basic optical path structure of the laser welding mechanism 2 described above is all existing technology.

[0027] Inside the vertical cylinder 22, between the protective lens 24 and the nozzle 23, a cleaning unit 3 and a protective gas unit 4 are arranged sequentially from top to bottom. The protective gas unit 4 is used to supply welding protective gas to the nozzle 23, so that the protective gas and the laser are coaxially ejected from the nozzle 23 to achieve gas protection of the molten pool. The cleaning unit 3 is used to perform active gas film protection and purging cleaning on the lower surface of the protective lens 24.

[0028] Specifically, such as Figure 5 , Figures 8 to 10 The cleaning unit 3 mainly includes an air ring seat 31, an air supply component, an exhaust component, a rotary drive assembly 34, and a transmission structure 35.

[0029] The gas ring seat 31 has an overall ring structure and is coaxially arranged inside the vertical cylinder 22, below the periphery of the protective lens 24. The center of the gas ring seat 31 is the light-transmitting area, and the light-transmitting aperture is larger than the maximum diffusion diameter of the laser beam and the coaxial visual field range, so it will not block the laser light path and the visual imaging path.

[0030] like Figure 8 As shown, the air ring seat 31 adopts a split structure, consisting of a first ring seat 311, a second ring seat 312, and a guide ring seat 36.

[0031] The guide ring seat 36 is a fixing component, which is snapped onto the inner wall step of the vertical cylinder 22 and is located directly below and abuts against the protective lens 24. The top of the guide ring seat 36 has a guide opening 361, which is obliquely arranged relative to the lower surface of the protective lens 24, which can constrain the blowing airflow to extend along the lens surface and improve the air film formation effect; the bottom of the guide ring seat 36 has an annular rotating groove 362, which is connected to the guide opening 361.

[0032] Both the first ring seat 311 and the second ring seat 312 are annular components, coaxially assembled and linked to each other for synchronous rotation. Specifically, the outer circumference of the first ring seat 311 is recessed inward to form a fitting annular groove 316, and the second ring seat 312 is fitted into the fitting annular groove 316 to achieve a fixed connection.

[0033] Both the first ring seat 311 and the second ring seat 312 have upwardly protruding extensions 315 at their tops. The extensions 315 are arc-shaped structures coaxial with the guide ring seat 36. The upper ends of the extensions 315 extend into the rotating groove 362 and can slide circumferentially along the rotating groove 362. The extensions 315 of the second ring seat 312 abut against the top of the first ring seat 311. The extensions 315 of the two ring seats can be joined to form a complete ring structure that matches the shape of the rotating groove 362. This maintains the airtightness of the airflow in the groove during rotation and also enables the limiting contact between the first ring seat 311 and the second ring seat 312, ensuring stable rotation.

[0034] The blowing port 313 is located on the upper end face of the extension 315 of the first ring seat 311, and the suction port 314 is located on the upper end face of the extension 315 of the second ring seat 312. The outlets of the blowing port 313 and the suction port 314 are both facing the lower surface of the protective lens 24 and are arranged symmetrically in the circumferential direction to ensure that the blowing and suction paths are matched and to improve the efficiency of pollutant collection.

[0035] The air supply component includes an air supply pipe 32 and an external clean and dry air source, which can be compressed air or inert protective gas that has been filtered to remove water and oil. It is connected to the air outlet 313 through an airflow channel 37 opened in the vertical cylinder 22. The airflow channel 37 includes a tubular distribution pipe 371 arranged around the first ring seat 311. A first air chamber 372 is opened inside the first ring seat 311, and the upper end of the first air chamber 372 is connected to the air outlet 313.

[0036] The exhaust component includes an exhaust pipe 33 and an external negative pressure suction device, which can be a vacuum generator or connected to a negative pressure dust removal pipeline in the workshop. It is connected to the suction port 314 through the exhaust channel 38 opened in the vertical cylinder 22.

[0037] To ensure continuous airflow during the rotation of the air ring seat 31, the transmission structure 35 is divided into a first transmission component and a second transmission component, corresponding to the air supply side and the exhaust side, respectively.

[0038] The first transmission assembly and the second transmission assembly have the same structural principle, both including a transfer air chamber 351, a sealing ring 352, and a connecting pipe 353. Taking the first transmission assembly as an example: the transfer air chamber 351 is an annular groove opened on the outer periphery of the first ring seat 311, which is connected to the first air chamber 372; the sealing ring 352 is made of wear-resistant self-lubricating material (such as polytetrafluoroethylene filling), and is installed at the opening of the transfer air chamber 351 by rotational sealing, and the outer side of the sealing ring 352 is fixed relative to the inner wall of the vertical cylinder 22; the connecting pipe 353 is opened on the sealing ring 352, one end of which is connected to the distribution pipe 371, and the other end is connected to the transfer air chamber 351.

[0039] When the first ring seat 311 rotates, the sealing ring 352 remains stationary, and the transfer air chamber 351 rotates synchronously with the ring seat, always maintaining airflow communication with the connecting pipe 353 through the sealing ring 352. Simultaneously, the sealing ring 352 ensures gas sealing between the moving and stationary parts, preventing leakage. The structure of the second transmission assembly is the same as the first transmission assembly. The transfer air chamber 351 is located on the outer periphery of the second ring seat 312, communicating with the intake port 314, and maintaining communication with the exhaust port 38 through the sealing ring 352.

[0040] like Figures 7-10 As shown, the rotary drive assembly 34 is used to drive the first ring seat 311 and the second ring seat 312 to rotate synchronously. In this embodiment, a pneumatic drive method is used, which does not require an additional motor.

[0041] Specifically, a drive ring groove 341 is formed on the outer periphery of the first ring seat 311, and several obliquely arranged blades 342 are uniformly fixed on the inner wall of the drive ring groove 341 along the circumference; an annular pressurizing chamber 343 is formed on the inner wall of the vertical cylinder 22 at the corresponding position, the pressurizing chamber 343 is arranged around the drive ring groove 341, and the pressurizing chamber 343 is connected to the distribution pipe 371; several air jet holes 344 are formed on the inner side wall of the pressurizing chamber 343, and the orientation of the air jet holes 344 corresponds to the inclination direction of the blades 342.

[0042] During operation, a portion of the high-pressure clean gas in the distribution pipe 371 enters the first air chamber 372 to clean the lens, while the other portion enters the pressurization chamber 343 and is sprayed at high speed onto the blades 342 through the jet nozzles 344. The airflow thrust drives the first ring seat 311 to rotate slowly around its axis, which in turn drives the second ring seat 312 to rotate synchronously. This driving method can be achieved using existing air sources, has a compact structure, no mechanical vibration, is suitable for the narrow installation space inside the welding head, and does not affect the optical path accuracy.

[0043] like Figure 7As shown, the protective gas unit 4 is located below the cleaning unit 3 and above the nozzle 23, and mainly includes a guide ring plate 41 and a guide tube 43.

[0044] The guide ring plate 41 is fixed to the inner wall of the vertical cylinder 22 and has a U-shaped annular structure with an open bottom, forming a closed annular distribution cavity inside. A connecting hole 42 is provided on the outer wall of the guide ring plate 41, which is connected to an external welding protective gas source (gas supply component). After the external protective gas enters the annular distribution cavity, it first undergoes expansion, deceleration, and circumferential pressure equalization to eliminate pressure deviation caused by unilateral air intake, providing a uniform and stable gas source for the downstream gas path. Simultaneously, the bottom opening of the guide ring plate 41 provides guidance for the airflow to move towards the nozzle 23, thereby constraining the airflow.

[0045] The guide tube 43 is coaxially fixed at the lower end of the vertical cylinder 22, near the nozzle 23. The guide tube 43 is a hollow annular high-pressure cavity structure. Several guide holes 44 are evenly opened on its wall along the circumference. The guide holes 44 are inclined towards the nozzle 23, and the diameter of the holes is smaller than the cross-section of the inner cavity of the guide tube 43, forming a throttling hole structure.

[0046] An air passage 45 is provided inside the side wall of the vertical cylinder 22. The upper end of the air passage 45 is connected to the connecting hole 42 of the guide ring plate 41, and the lower end is connected to the hollow inner cavity of the guide pipe 43.

[0047] During operation, the welding shielding gas enters the annular distribution cavity of the guide ring plate 41 through the connecting hole 42 to complete pressure equalization and rectification. At the same time, a small portion of the gas flow is transported downwards along the gas passage 45 at the connecting hole 42 to the inner cavity of the guide pipe 43. The high-pressure gas is accelerated by throttling through the guide hole 44, forming multiple high-speed jets that are axially downwards. The high-speed jets continuously entrain the surrounding gas downwards through viscous shearing, forming a stable low-pressure zone around the jets. This exerts a downward traction and ejection effect on the overall gas in the vertical cylinder 22 located at the guide ring plate 41, forcing most of the gas flow in the cylinder to flow orderly towards the nozzle 23, and finally being coaxially ejected from the nozzle 23 to cover the molten pool.

[0048] This structure actively constrains the airflow direction by using high-speed jet ejection, which can eliminate the upward backflow vortex caused by unilateral air intake at the source and cut off the internal pollution path of the pipeline itself carrying pollutants upward. At the same time, it can homogenize the airflow velocity distribution of the cylinder cross section, weaken the central low-pressure area, reduce the probability of reverse diffusion of smoke and dust, improve the laminar flow stability of the jet at the nozzle 23 outlet and the molten pool protection effect, and adapt to multi-posture welding conditions.

[0049] Based on the above structure, such as Figures 3-5As shown, the vertical cylinder 22 adopts a modular segmented design, which is split into multiple segments along the axial direction, processed independently, and then assembled. This ensures the machining accuracy and coaxiality of the internal cavity of each segment, and also facilitates the step-by-step assembly and subsequent maintenance of internal optical components and gas circuit components. From top to bottom, it is divided into a focusing lens mounting section 51, a lens mounting section 52, a cleaning mounting section 53, a protective gas mounting section 54, and a nozzle connection section 55. The segments are connected by a unified stop positioning, flange locking, and end face sealing method.

[0050] Specifically, the mating end faces of adjacent sections are machined with male and female stops respectively. The stop fit is a clearance fit, which reduces the coaxiality error of the inner cavity axes of each section after assembly, preventing optical path eccentricity from affecting the quality of the focused spot. In addition, an annular sealing groove is opened at the root of the male stop, and a fluororubber O-ring is embedded in the groove. After locking, the O-ring is deformed by the pressure of the flange surface, achieving static sealing between sections. This effectively prevents external dust and moisture from entering the cylinder, while separating different functional chambers and preventing gas flow.

[0051] Each section of the vertical cylinder 22 has a radially extending flange at the joint. The flange face has 65 holes for internal hexagonal locking screws evenly arranged around the circumference. After assembly and alignment, the screws are axially locked, ensuring reliable connection strength and convenient assembly and disassembly.

[0052] In addition, the protective lens 24 assembly adopts the industry-standard side-drawer module structure, which is a mature quick-change design. The circular protective lens 24 is embedded in the central through hole of the drawer base 61. An inwardly protruding step is provided above the through hole to support the upper surface of the lens, and a thin fluororubber buffer ring 63 is placed on the step surface. A lens pressure ring 62 is provided below the lens, and a buffer ring 63 is also placed on the upper surface of the lens pressure ring 62 to prevent the locking stress from cracking the lens, while ensuring that the lens is subjected to uniform force in the circumference.

[0053] The side wall of the lens mounting section 52 has a rectangular insertion port that matches the shape of the drawer seat 61. The drawer seat 61 is pushed horizontally into the cylinder along the insertion port. A positioning pin is set at a corresponding position inside the cylinder, which precisely matches the positioning hole on the side of the drawer seat 61. After being pushed in, it automatically completes radial positioning, ensuring that the center of the lens is completely aligned with the optical path axis. A locking screw 65 is set on the outside of the drawer seat 61. After being pushed in, tightening it will complete the axial locking and prevent loosening during operation.

[0054] A ring-shaped sealing groove is opened on the upper and lower end faces of the drawer seat 61, and an O-ring is installed in the groove. After assembly, the upper sealing ring abuts against the lower step surface of the focusing lens cavity, and the lower sealing ring abuts against the upper step surface of the cleaning cavity, completely physically separating the upstream precision optical cavity from the downstream cleaning air cavity. This not only prevents the smoke and water vapor below from eroding the focusing lens and beam splitter 25 upwards, but also prevents the upstream clean gas from flowing downwards and interfering with the gas path balance.

[0055] When replacing the protective lens 24, simply loosen the locking structure and pull out the drawer seat 61 horizontally to complete the lens replacement. There is no need to disassemble other sections of the cylinder and optical components. The replacement time can be controlled within 30 seconds, which greatly reduces the downtime of equipment maintenance and is suitable for the fast-paced production needs of automated production lines.

[0056] Working process: Before welding starts, the gas supply and exhaust components are turned on in advance. Clean gas enters the first gas chamber 372 through the airflow channel 37, distribution pipe 371, and transfer gas chamber 351, and is finally sprayed obliquely from the blowing port 313 onto the lower surface of the protective lens 24, extending along the lens surface to form a flowing protective gas film. At the same time, the exhaust component generates negative pressure through the suction port 314, synchronously drawing out the purged gas and the air in the chamber. Meanwhile, part of the airflow enters the pressurization chamber 343, blows the blades 342 through the jet port 344, and drives the gas ring seat 31 to start rotating at a low speed, establishing full-circumference active protection before laser emission, covering the protection gap during the arc initiation stage.

[0057] Laser beams are used for welding. The protective gas unit 4 uses a high-speed jet to guide the overall airflow inside the cylinder downwards in an orderly manner. The gas is then coaxially ejected from the nozzle 23 to cover the molten pool, isolating it from air and preventing weld oxidation. When spatter and metal vapor generated during welding diffuse upwards, they are first blocked by the downward mainstream field at the nozzle 23. When a small amount of contaminants penetrate the main gas layer and reach the cleaning unit 3 area, they are blocked by the dynamic gas film below the protective lens 24 and cannot directly contact the lens surface. At the same time, the gas ring seat 31 continues to rotate, and the air blowing port 313 circulates and sweeps the entire circumference of the lens, blowing up ultrafine fumes, which are then sucked out by the adjacent air intake port 314 to prevent the accumulation of contaminants.

[0058] In this embodiment, the suction flow rate of the exhaust component is set to 1.1 to 1.2 times the jet flow rate of the gas supply component. All the purging gas is drawn away in a directional manner, and will not flow downwards to interfere with the main protective gas flow field, thus ensuring the stability of welding process parameters and not affecting the weld formation quality.

[0059] After the laser is turned off, the gas supply and exhaust components shut down after a delay, continuously blowing away the residual high-temperature metal vapor in the suction chamber to prevent the vapor from cooling and condensing on the surface of the protective lens 24, thus filling the protection gap during the arc termination phase.

[0060] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this application, it should be understood that if terms such as "upper," "lower," "left," and "right" 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, the terms used to describe positional relationships in the accompanying drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0061] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A robotic arm welding device, comprising a robotic arm mechanism (1) and a laser welding mechanism (2) connected to the robotic arm mechanism (1), wherein the laser welding mechanism (2) comprises a vertical cylinder (22) with a nozzle (23) at one end, and a protective lens (24) is disposed inside the vertical cylinder (22); characterized in that, It also includes a cleaning unit (3) disposed between the protective lens (24) and the nozzle (23) and a protective gas unit (4), the protective gas unit (4) being used to spray protective gas outward through the nozzle (23); The cleaning unit (3) includes an air ring seat (31) disposed in a vertical cylinder (22). The air ring seat (31) has an annular structure and is located below the periphery of the protective lens (24). The air ring seat (31) is provided with an air blowing port (313) and an air intake port (314) corresponding to the protective lens (24). The air blowing port (313) and the air intake port (314) are symmetrically disposed on the air ring seat (31) and are respectively connected to an air supply component and an air exhaust component. The air supply component is connected to the air blowing port (313) and is used to spray clean gas onto the surface of the protective lens (24) through the air blowing port (313) to form a flowing air film on the surface of the protective lens (24). The air exhaust component is connected to the air intake port (314) and is used to guide the gas at the protective lens (24) outward and discharge it to the outside through the air intake port (314).

2. The robotic arm welding equipment according to claim 1, characterized in that, The air ring seat (31) is rotatably assembled inside the vertical cylinder (22). A rotary drive assembly (34) is provided between the air ring seat (31) and the vertical cylinder (22). The rotary drive assembly (34) is used to drive the air ring seat (31) to rotate within the vertical cylinder (22) along the center of the protective lens (24). It also includes a transmission structure (35) provided between the air ring seat (31) and the air supply component and the air exhaust component. The transmission structure (35) is used to ensure that the air supply component and the air exhaust component are always connected to the air blowing port (313) and the air intake port (314) when the air ring seat (31) rotates.

3. The robotic arm welding equipment according to claim 2, characterized in that, The air ring seat (31) is composed of a first ring seat (311) and a second ring seat (312). The first ring seat (311) and the second ring seat (312) are coaxially arranged and linked to each other to achieve synchronous rotation. The air blowing port (313) is arranged on the first ring seat (311) and the air intake port (314) is arranged on the second ring seat (312). The transmission structure (35) includes a first transmission component arranged between the first ring seat (311) and the air supply component, and a second transmission component arranged between the second ring seat (312) and the exhaust component.

4. The robotic arm welding equipment according to claim 3, characterized in that, The air ring seat (31) also includes a guide ring seat (36) fixedly installed in the vertical cylinder (22). The top of the guide ring seat (36) is provided with a guide port (361) obliquely arranged relative to the surface of the protective lens (24), and the bottom of the guide ring seat (36) is provided with a rotating groove (362) communicating with the guide port (361). The tops of the first ring seat (311) and the second ring seat (312) are both raised to form an extension (315). The extension (315) is an arc shape coaxial with the guide ring seat (36), and its end extends into the rotating groove (362) and can rotate along the rotating groove (362). The blowing port (313) and the suction port (314) are respectively provided at the end of the extension (315) located in the rotating groove (362).

5. The robotic arm welding equipment according to claim 4, characterized in that, The first ring seat (311) has an inwardly recessed groove (316) on its outer circumference. The second ring seat (312) is fitted into the groove (316) to achieve coaxial arrangement with the first ring seat (311). The extension (315) of the second ring seat (312) abuts against the top of the first ring seat (311) and can be combined with the extension (315) of the first ring seat (311) to form a ring structure.

6. The robotic arm welding equipment according to claim 3, characterized in that, Both the first transmission assembly and the second transmission assembly include a transfer air chamber (351) disposed around the first ring seat (311) and the second ring seat (312), the transfer air chamber (351) being connected to an air inlet (314) or an air outlet (313); and also include a sealing ring (352) rotatably disposed at the opening of the transfer air chamber (351), the sealing ring (352) being provided with a connecting pipe (353) connecting to an air supply component or an air exhaust component.

7. The robotic arm welding equipment according to claim 6, characterized in that, An airflow channel (37) is provided between the air supply component and the air outlet (313) on the first ring seat (311). The airflow channel (37) is provided on the vertical cylinder (22) and includes a distribution pipe (371) provided in the vertical cylinder (22) and located on the periphery of the first ring seat (311); it also includes a first air chamber (372) provided in the first ring seat (311) and connected to the air outlet (313). The first air chamber (372) is connected to the transfer air chamber (351) on the first ring seat (311). The distribution pipe (371) is connected to the transfer air chamber (351) on the first ring seat (311) through a corresponding connecting pipe (353).

8. The robotic arm welding equipment according to claim 7, characterized in that, The rotary drive assembly (34) includes a drive ring groove (341) disposed around the first ring seat (311), and a plurality of obliquely arranged blades (342) are fixedly disposed on the inner wall of the drive ring groove (341); it also includes a pressurizing chamber (343) disposed in the vertical cylinder (22) and connected to the distribution pipe (371), the pressurizing chamber (343) is disposed around the drive ring groove (341), and a plurality of jet holes (344) connected to the pressurizing chamber (343) are disposed on the inner wall of the vertical cylinder (22), and the plurality of jet holes (344) are disposed toward the blades (342) for driving the first ring seat (311) to rotate by blowing the blades (342).

9. A robotic arm welding device according to claim 6, characterized in that, The vertical cylinder is provided with an exhaust channel (38) corresponding to the position of the transfer air chamber (351) on the second ring seat (312). The exhaust channel (38) is used to connect the exhaust component with the transfer air chamber (351) on the second ring seat (312).

10. A robotic arm welding device according to claim 1, characterized in that, The protective gas unit (4) includes a guide ring plate (41) disposed on the inner wall of the vertical cylinder. The guide ring plate has a U-shaped structure with an open bottom and a connecting hole (42) for communicating with the gas delivery component on its inner wall. It also includes a guide pipe (43) disposed in the vertical cylinder and located at the nozzle (23). The guide pipe (43) is hollow and has several guide holes (44) on its upper part facing the nozzle (23). The vertical cylinder has a gas passage (45) for communicating with the connecting hole (42) and the guide pipe (43).

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