Local vacuum laser welding device

Abstract

The application provides a local vacuum laser welding device, and belongs to the technical field of vacuum laser welding device design, which comprises a vacuum cover, wherein the vacuum cover comprises a sealed cover body and a vacuum cylinder connected to the side of the sealed cover body away from a workpiece to be welded; a laser incidence port is formed on the sealed cover body; a laser protection lens coaxially arranged with the laser incidence port is arranged in the end of the vacuum cylinder away from the laser incidence port; a smoke dust blocking piece is arranged in the end of the vacuum cylinder close to the laser incidence port; a laser via hole for laser to pass through is formed in the smoke dust blocking piece; and the diameter of the laser via hole is smaller than the diameter of the laser incidence port. The application effectively reduces the probability of the aforementioned pollutants contacting the laser protection lens along the vacuum cylinder upward, thereby prolonging the occurrence period of the particle adhesion, desublimation and frosting phenomenon of the pollutants on the laser protection lens, so that the problem of welding power reduction caused by lens pollution can be prevented, thereby ensuring the weld quality and preventing the phenomenon of long-time welding lens high-temperature burst.

Description

Technical Field

[0001] This invention belongs to the field of vacuum laser welding equipment design technology, and specifically relates to a local vacuum laser welding device. Background Technology

[0002] Localized vacuum laser welding creates a closed, low-pressure vacuum environment in a localized area of ​​the weld joint, effectively suppressing photo-induced plasma during laser welding, reducing weld oxidation, minimizing porosity defects, and increasing weld penetration. It is widely used in welding high-requirement components in aerospace, pressure vessels, precision machinery, and new energy industries.

[0003] In actual localized vacuum laser continuous welding operations, the high-power laser beam focuses and melts the workpiece, continuously generating a large amount of high-temperature metal vapor, suspended fumes, and molten spatter particles. These contaminants are vertically dispersed upwards along the laser beam path under the influence of the thermal plume. The laser protective lens at the bottom of the laser head is a vulnerable optical component. Long-term exposure to the upward contaminant environment easily leads to contamination problems such as particle adhesion, metal vapor sublimation and frost formation, and high-temperature ablation and oxidation. This reduces the laser beam transmittance, decreases welding power, and lowers weld quality. In addition, the contaminated lens will heat up, posing a risk of high-temperature breakage during prolonged welding. Summary of the Invention

[0004] Therefore, the present invention provides a local vacuum laser welding device that can overcome the contamination problems of laser protective lenses in related technologies, such as particle adhesion, metal vapor sublimation and frost formation, and high-temperature ablation and oxidation, which lead to a decrease in welding power, a reduction in weld quality, and a risk of lens high-temperature cracking during long-term welding.

[0005] To address the aforementioned problems, this invention provides a local vacuum laser welding device, comprising a vacuum hood, the vacuum hood including a sealed cover and a vacuum cylinder connected to the side of the sealed cover away from the workpiece to be welded, a laser inlet formed on the sealed cover, a laser protection lens coaxially disposed with the laser inlet at one end of the vacuum cylinder away from the laser inlet, and a fume blocking component at one end near the laser inlet, the fume blocking component having a laser through hole for laser passage, the diameter of the laser through hole being smaller than the diameter of the laser inlet.

[0006] Preferably, the smoke and dust blocking component includes a mounting cylinder coaxially arranged with the laser inlet and a plurality of blocking plates inside the mounting cylinder. Each blocking plate is spaced apart along the incident direction of the laser, and a laser through hole is formed at the center of each blocking plate. The diameter of the laser through hole on each blocking plate decreases along the incident direction.

[0007] Preferably, each of the blocking plates has a flow-deflecting protrusion formed on the side closest to the workpiece to be welded, each of the flow-deflecting protrusions is frustoconical, and the small-diameter end face of the flow-deflecting protrusion is close to the workpiece to be welded, and the laser via penetrates through both end faces of the flow-deflecting protrusion; and / or, an expansion cavity is formed between adjacent blocking plates; and / or, a buffer space is formed between the blocking plate closest to the laser inlet and the sealing cover.

[0008] Preferably, the diameter of each laser via decreases along the incident direction.

[0009] Preferably, the mounting cylinder is integrally formed with each of the blocking plates; and / or, the mounting cylinder has a mounting flange extending radially outward therefrom, the end of the vacuum cylinder near the workpiece to be welded is welded to the mounting flange, and the mounting flange is detachably connected to the sealing cover.

[0010] Preferably, the local vacuum laser welding device further includes an air curtain dust blocking component, which includes an air curtain output component located inside the vacuum cylinder and on the side of the laser protection lens near the laser entrance.

[0011] Preferably, a vacuum port is formed on the wall of the vacuum cylinder, the vacuum port is controllably connected to an external vacuum suction system, and the vacuum port is located between the smoke and dust blocking component and the air curtain dust blocking component.

[0012] Preferably, the air curtain output component includes a flow divider ring and a plurality of airflow nozzles spaced apart on the inner ring wall of the flow divider ring along the circumferential direction. An annular air passage is formed in the flow divider ring, and each of the airflow nozzles is connected to the annular air passage. The laser protection lens is assembled on the vacuum cylinder via a lens holder, and the flow divider ring is detachably assembled on the lens holder.

[0013] Preferably, the jet direction of each of the airflow nozzles forms an angle α with the central axis of the flow divider ring, where 10°≤α≤35°; and / or, the cross-section of the nozzle orifice is rectangular.

[0014] Preferably, the diameter of the laser via is not less than 2 mm and not more than 30 mm; and / or, the distance between two adjacent blocking plates is not less than 10 mm and not more than 40 mm; and / or, the surface roughness Ra of the dust blocking component is ≤0.8 μm; and / or, there are at least three blocking plates.

[0015] The local vacuum laser welding device provided by this invention has the following beneficial effects:

[0016] A fume-blocking component with a laser via is installed at the laser entrance. The diameter of the laser via is smaller than the diameter of the laser entrance. This allows the laser beam to reach the area to be welded on the workpiece without obstructing its propagation, while also actively blocking and isolating contaminants such as fumes and metal vapors at the welding location. This effectively reduces the probability of these contaminants coming into contact with the laser protective lens as they travel upwards through the vacuum cylinder. Consequently, it prolongs the period during which these contaminants adhere to the laser protective lens and undergo sublimation and frost formation. This prevents the lens from contaminating and causing a decrease in welding power, thus ensuring weld quality and preventing the lens from cracking due to high temperatures during prolonged welding. In addition, the fume-blocking component can also isolate the high temperature at the weld, effectively reducing the risk of thermal damage to the laser protective lens. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. The drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of the local vacuum laser welding device in an embodiment of the present invention;

[0019] Figure 2 yes Figure 1 A cross-sectional schematic diagram of the smoke and dust blocking component in the diagram;

[0020] Figure 3 yes Figure 1 A top view of the air curtain output component;

[0021] Figure 4 yes Figure 3 A cross-sectional schematic diagram of the air curtain output component.

[0022] The attached figures are labeled as follows:

[0023] 11. Sealing cover; 110. Laser entrance port; 111. Buffer space; 12. Vacuum cylinder; 121. Vacuum extraction interface; 13. Sealing ring; 2. Laser protection lens; 21. Lens mount; 3. Smoke and dust blocking component; 30. Laser through hole; 31. Mounting cylinder; 311. Mounting flange; 32. Baffle plate; 320. Expansion cavity; 321. Baffle ring; 41. Gas curtain output component; 410. Annular gas path; 411. Diverter ring; 412. Airflow nozzle; 42. Pressure tank; 43. On / off control valve; 44. Control component; 100. Workpiece to be welded; 200. Laser welding head; 300. Laser beam. Detailed Implementation

[0024] 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. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. 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.

[0025] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms 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, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0026] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90° or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0027] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0028] See also Figures 1 to 4As shown in the figure, according to an embodiment of the present invention, a local vacuum laser welding device is provided, including a vacuum hood (not indicated in the figure). The vacuum hood includes a sealing hood body 11 and a vacuum cylinder 12 connected to the side of the sealing hood body 11 away from the workpiece 100 to be welded. A sealing ring 13 is provided on the end face of the sealing hood body 11 that mates with the workpiece 100 to be welded. Generally, the sealing ring 13 should have a certain elastic deformation capacity and high temperature resistance and wear resistance to ensure the sealing isolation effect between the sealing hood body 11 and the surface of the workpiece 100 to be welded during the welding process. A laser inlet 110 is formed on the sealing hood body 11. The vacuum cylinder 12 has a laser protection lens 2 coaxially arranged with the laser entrance 110 at one end away from the laser entrance 110, and a smoke and dust blocking component 3 at the other end near the laser entrance 110. The smoke and dust blocking component 3 has a laser through hole 30 for the laser to pass through. The diameter of the laser through hole 30 is smaller than the diameter of the laser entrance 110. It is understood that the diameter of the aforementioned laser through hole 30 should be larger than the diameter of the laser beam 300 corresponding to the position of the laser through hole 30, so as to ensure that the laser beam 300 can be directed to the welding area of ​​the workpiece 100 below without obstruction.

[0029] In this technical solution, a fume blocking component 3 with a laser via 30 is provided at the laser entrance 110. The diameter of the laser via 30 is smaller than the diameter of the laser entrance 110. This allows the laser beam 300 to reach the area to be welded on the workpiece without obstructing the propagation of the laser beam 300. At the same time, it can actively block and isolate contaminants such as fumes and metal vapors at the welding position to the greatest extent. This effectively reduces the probability of the aforementioned contaminants coming into contact with the laser protection lens 2 as they travel upwards along the vacuum cylinder 12. This extends the period during which the aforementioned contaminants adhere to the laser protection lens 2 and undergo particle deposition and frost formation. This can prevent the problem of reduced welding power caused by lens contamination, thereby ensuring weld quality and preventing the phenomenon of high-temperature cracking of the lens during long-term welding. In addition, the aforementioned fume blocking component 3 may also isolate the high temperature at the weld to a certain extent, effectively reducing the risk of thermal damage to the laser protection lens 2.

[0030] It is understandable that during the vacuum welding process, a large amount of plasma, metal vapor, fumes and other contaminants will be generated at the weld pool. These contaminants will enter the vacuum cylinder 12 upwards from the laser inlet 110 in the form of airflow diffusion. Due to the setting of the fume blocking component 3 mentioned above, the contaminant fluid will be collided, intercepted and slowed down by the smaller diameter laser through hole 30. When the particulate matter (including metal vapor) in the contaminant flows through the fume blocking component 3, most of it will be intercepted and deposited, thereby reducing the deposition and frost formation of the contaminant fluid on the aforementioned laser protection lens 2. It is worth emphasizing that the metal vapor in the contaminant fluid will sublimate and frost on the fume blocking component 3 in advance, thereby achieving substitute protection for the laser protection lens 2.

[0031] Preferably, the smoke and dust blocking component 3 includes a mounting cylinder 31 coaxially arranged with the laser inlet 110 and a plurality of blocking plates 32 located inside the mounting cylinder 31. Each blocking plate 32 is spaced apart along the incident direction of the laser, and each blocking plate 32 has a laser via 30 formed at its center. The diameter of the laser via 30 on each blocking plate 32 decreases along the incident direction; that is, along the laser incident direction, the diameter of the laser via 30 on the upstream side is larger than that on the downstream side. The specific number of the aforementioned blocking plates 32 can be flexibly selected according to requirements. For example, the number of blocking plates 32 in the mounting cylinder 31 is not less than three. Figure 1 Three are shown to ensure that they block the aforementioned pollutants in a tiered manner, thereby improving the dust suppression effect.

[0032] In this technical solution, by simultaneously setting multiple blocking plates 32 spaced apart along the laser incident direction inside the mounting cylinder 31, multiple tiered blocking of various fumes generated during the welding process can be formed, effectively improving the interception effect of welding contaminants.

[0033] Please see Figure 2 As shown, an expansion cavity 320 is formed between adjacent blocking plates 32. The expansion cavity 320 is generally a cylindrical cavity with a diameter much larger than the diameter of each laser via 30. In practical applications, the flue gas (i.e., the aforementioned pollutant fluid) enters the expansion cavity 320 after passing through the laser via 30, causing it to expand and decelerate. The decelerated flue gas is more easily trapped and deposited on the bottom wall of the expansion cavity 320. This achieves both flue gas trapping and flue gas containment, preventing the trapped flue gas from falling back into the welding area below and adversely affecting the welding quality.

[0034] A buffer space 111 is formed between the blocking plate 32, which is closest to the laser inlet 110, and the sealing cover 11. That is, the blocking plate 32 has a height difference with the laser inlet 110, rather than being tightly attached vertically. The buffer space 111 helps to disperse the smoke and dust generated during the welding process in a timely manner, preventing the excessive concentration of plasma, plume, etc. from accumulating at the laser inlet 110, ensuring the smooth entry of the laser beam 300 and thus ensuring the quality of laser welding.

[0035] Generally speaking, the inner diameter of the aforementioned mounting cylinder 31 is not less than the diameter of the aforementioned laser inlet 110, so as to ensure the expansion effect of each of the aforementioned expansion cavities 320.

[0036] Preferably, each of the blocking plates 32 has a flow-deflecting protrusion 321 formed on one side near the workpiece 100 to be welded. Each flow-deflecting protrusion 321 is frustoconical, and the small-diameter end face of the flow-deflecting protrusion 321 is close to the workpiece 100 to be welded. The laser via 30 penetrates both end faces of the flow-deflecting protrusion 321. See [reference needed] Figure 2 As shown, the positions where each deflector ring 321 intersects with the bottom end face of each baffle plate 32 are rounded to smoothly guide the airflow of smoke and dust.

[0037] In this technical solution, by further setting a frustum-shaped baffle ring 321 on the side of each baffle 32 near the workpiece 100 to be welded, the flue gas flow entering the aforementioned buffer space 111, especially entering each expansion cavity 320, can form a reverse flow in the cavity, thereby improving the particle collision deposition and metal vapor sublimation attachment precipitation effect in the flue gas flow.

[0038] Preferably, the diameter of each laser via 30 decreases along the incident direction, see details below. Figure 2 As shown, each laser via 30 is objectively a conical hole, which can be matched with the size of the conical laser beam 300 at different heights, ensuring that the laser beam 300 passes through without obstruction while minimizing the probability of smoke and dust airflow passing directly through the laser via 30, thereby improving the smoke and dust interception effect.

[0039] To improve the service life of the aforementioned dust blocking component 3, it is preferably made of high-temperature resistant alloys such as 310S stainless steel. The outer wall surface of the dust blocking component 3 is polished to ensure that its surface roughness Ra≤0.8μm, so as to reduce the adhesion of metal vapor on it, thereby achieving the purpose of more easily falling off after sublimation, preventing excessive deposition and adhesion at the laser via 30, reducing the aperture, and thus obstructing the emission of the laser beam 300.

[0040] Preferably, the mounting cylinder 31 and each of the blocking plates 32 are integrally formed, which can reduce the number of components to be assembled, improve assembly and application efficiency, and more importantly, reduce the leakage of smoke and dust airflow caused by assembly gaps.

[0041] Preferably, the mounting cylinder 31 has a mounting flange 311 extending radially outward. The end of the vacuum cylinder 12 near the workpiece 100 to be welded is welded to the mounting flange 311 to reduce assembly gaps. This helps improve the sealing performance of the device and thus ensures the vacuum level. The mounting flange 311 is detachably connected to the sealing cover 11. For example, the mounting flange 311 has corresponding connection holes, and the detachable connection with the sealing cover 11 is achieved through each connection hole. During specific assembly, a corresponding sealing gasket or sealing ring should be provided at the fit gap between the mounting flange 311 and the sealing cover 11.

[0042] Preferably, the diameter of the laser via 30 is not less than 2 mm and not more than 30 mm, the distance between two adjacent blocking plates 32 is not less than 10 mm and not more than 40 mm, and the overall axial height of each of the aforementioned blocking plates 32 is 5 to 50 mm.

[0043] Preferably, the local vacuum laser welding device further includes an air curtain dust blocking component, which includes an air curtain output component 41. The air curtain output component 41 is located inside the vacuum cylinder 12 and on the side of the laser protection lens 2 near the laser entrance port 110. Generally, the airflow output by the aforementioned air curtain output component 41 is an inert airflow, such as argon, which will not affect the welding quality of the workpiece 100 to be welded.

[0044] In this technical solution, by setting an air curtain dust-blocking component in the inner area of ​​the laser protective lens 2 inside the vacuum cylinder 12, the airflow output by the air curtain dust-blocking component forms a positive pressure air curtain, which can further reduce the small amount of smoke and dust that rises from below, further reduce the probability of smoke and dust directly contacting the laser protective lens 2, and improve the laser protective lens 2 to be in a clean and pollution-free state.

[0045] See details Figure 1 As shown, the air curtain dust suppression assembly also includes a pressure tank 42 for storing pressurized gas (such as argon). The pressure tank 42 is connected to the air curtain output component 41 via a pipeline. An on / off control valve 43 is provided on the connecting pipeline, and a control component 44 (such as an industrial computer) is provided in conjunction with the on / off control valve 43 to control the on / off of the on / off control valve 43 according to set instructions, thereby realizing intermittent gas supply to the air curtain output component 41. The aforementioned control component 44 is used to store and execute programs for parameters such as the on / off interval and single connection duration of the on / off control valve 43.

[0046] Preferably, a vacuum port 121 is formed on the wall of the vacuum cylinder 12, the vacuum port 121 is controllably connected to an external vacuum suction system (not shown in the figure), and the vacuum port 121 is located between the smoke and dust blocking component 3 and the air curtain dust blocking component.

[0047] In this technical solution, the vacuum port 121 can be used to evacuate the space inside the cover in real time during the vacuum laser welding process, ensuring that the space inside the cover is dynamically at the target vacuum level. It should also be noted that placing the vacuum port 121 between the fume blocking component 3 and the air curtain dust blocking component, at a distance from the weld pool, can reduce the disturbance of the weld pool caused by the airflow generated during vacuum evacuation, thus ensuring welding quality. At the same time, the airflow output by the air curtain dust blocking component can be drawn from top to bottom into the vacuum cylinder 12 and will not enter the welding area below, which can also avoid the disturbance of the weld pool by the positive pressure airflow.

[0048] Preferably, in conjunction with see Figure 3 and Figure 4 As shown, the air curtain output component 41 includes a flow divider ring 411 and a plurality of airflow nozzles 412 spaced along the circumferential direction of the flow divider ring 411 on the inner ring wall of the flow divider ring 411. An annular air passage 410 is formed inside the flow divider ring 411, and each of the airflow nozzles 412 is connected to the annular air passage 410. The laser protection lens 2 is assembled on the vacuum cylinder 12 via a lens mount 21, and the flow divider ring 411 is detachably assembled on the lens mount 21 (e.g., by screws).

[0049] In this technical solution, the aforementioned diversion ring 411 is coaxially arranged with the laser protection lens 2, and each airflow nozzle 412 is uniformly arrayed around the central light-transmitting area of ​​the laser protection lens 2. This can form a relatively stable air curtain to isolate and block the upward smoke and dust at the last stage, without causing any adverse effects on the propagation of the laser beam 300.

[0050] Preferably, see details. Figure 4As shown, the jet direction of each airflow nozzle 412 (i.e., the axial direction of each airflow nozzle 412) forms an angle α with the central axis of the diversion ring 411 (i.e., the surface normal direction of the aforementioned laser protection lens 2), where 10°≤a≤35°. When α is less than 10°, the jet of the airflow nozzle 412 is almost vertically downward, and the airflow flows vertically almost against the inner wall of the vacuum cylinder 12. The lateral diffusion is extremely narrow, and the airflow of adjacent nozzles cannot merge. There are a lot of gaps in the annular air curtain, and rising dust will directly enter the lens from the gaps between the nozzles, resulting in poor protection. When α is greater than 35°, the airflow is not deflected downward enough, which leads to insufficient downward pressure on the dust leaking from the dust blocking component 3. The dust directly rushes to the lens from the gaps below the air curtain, meaning that the annular air curtain has a poor interception effect on dust. In addition, when α is greater than 35°, the jets ejected by the airflow nozzles 412 in opposite positions are prone to generating turbulent vortices, which will instead raise more dust and contaminate the lens.

[0051] Preferably, the angle is 20°≤a≤25°. This angle balances the downward pressure on the airflow with the lateral diffusion, provides sufficient vertical velocity to effectively suppress the rising smoke and dust, has a moderate lateral diffusion distance, allows at least some nozzles to form a seamless ring, has sufficient overlap, and will not have gaps even with slight fluctuations in air pressure, and has moderate air consumption, resulting in the highest overall cost-effectiveness.

[0052] Preferably, the number of the aforementioned airflow nozzles 412 is 6 to 12. The specific number can be reasonably selected according to the required airflow density covering the area below the lens. The cross-section of the nozzle orifice of the airflow nozzle 412 is rectangular, making each airflow nozzle 412 flat and elongated. The width of the aforementioned rectangle is 2 to 25 mm and the height is 1 to 15 mm.

[0053] Preferably, during the welding process, the vacuum level inside the local vacuum sealing cover is controlled at 0.01 to 100 Pa, the argon gas supply pressure is 0.12 to 0.3 MPa, the duration of a single purging is 0.2 to 2 s, and the interval period is 2 to 10 s.

[0054] The specific application should be carried out according to the following steps:

[0055] S1: Workpiece clamping: Fix the workpiece to be welded (i.e., the aforementioned workpiece to be welded 100, the same below) to the positioning fixture (not shown in the figure, not involved in this invention), align the welding seam, and fasten and lock the local vacuum sealing cover (i.e. the local vacuum laser welding device of this invention) to achieve a sealed welding area.

[0056] S2: Vacuum establishment: Start the vacuum pumping system (i.e., the aforementioned external vacuum suction system) to evacuate the inside of the local vacuum sealing cover, maintain the vacuum level inside the cavity at 0.01~100Pa, and keep the pressure stable;

[0057] S3: Optical path calibration: Adjust the laser welding head (i.e., the laser welding head 200 of this invention), calibrate the focus of the laser beam (i.e., the aforementioned laser beam 300), so that the laser is precisely focused on the weld seam to be welded;

[0058] S4: Composite protection activation: Start the electrical control system and simultaneously activate the funnel blocking component (i.e., the aforementioned smoke and dust blocking component 3) and the intermittent argon gas protection component (i.e., the aforementioned air curtain dust blocking component).

[0059] S5: Long-term welding operation: Start the high-power laser generator to perform continuous laser welding; during the welding process, high-temperature fumes and metal vapors rise into the funnel-shaped baffle, and after buffering and flow reduction, most of the particles settle and remain in the inner cavity between the multi-layered funnel shape (i.e., the aforementioned expansion cavities 320); at the same time, the electromagnetic pulse control valve (i.e., the aforementioned on / off control valve 43) opens intermittently according to the preset sequence, and sprays high-purity argon gas intermittently onto the lower surface of the lens to blow away the weak floating dust and sublimated metal particles, forming a thin layer of inert protective gas film (i.e., gas curtain) at the small opening of the optical path.

[0060] S6: Cyclic Continuous Operation: Maintain stable local vacuum throughout the process, with dual protection of funnel physical blockage and intermittent air blowing, ensuring uninterrupted continuous welding; after welding is completed, turn off the laser, pulse air blowing system (i.e., the aforementioned air curtain dust blocking component), and vacuum pumping system in sequence, slowly depressurize the cavity, and remove the workpiece.

[0061] It will be readily understood by those skilled in the art that, without conflict, the advantageous technical features of the above-mentioned methods can be freely combined and superimposed.

[0062] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A local vacuum laser welding device, characterized in that, The system includes a vacuum hood, which includes a sealing hood body (11) and a vacuum cylinder (12) connected to the side of the sealing hood body (11) away from the workpiece (100) to be welded. A laser inlet (110) is formed on the sealing hood body (11). A laser protection lens (2) is provided in the end of the vacuum cylinder (12) away from the laser inlet (110) and is coaxially arranged with the laser inlet (110). A dust blocking component (3) is provided in the end of the vacuum cylinder (12) close to the laser inlet (110). A laser through hole (30) is formed in the dust blocking component (3) for the laser to pass through. The diameter of the laser through hole (30) is smaller than the diameter of the laser inlet (110).

2. The local vacuum laser welding apparatus according to claim 1, characterized in that, The smoke and dust blocking component (3) includes a mounting cylinder (31) coaxially arranged with the laser inlet (110) and a plurality of blocking plates (32) inside the mounting cylinder (31). Each blocking plate (32) is spaced apart along the incident direction of the laser. Each blocking plate (32) has a laser through hole (30) formed at its center, and the diameter of the laser through hole (30) on each blocking plate (32) becomes smaller and smaller along the incident direction.

3. The local vacuum laser welding apparatus according to claim 2, characterized in that, Each of the blocking plates (32) has a flow-deflecting protrusion (321) formed on the side of the workpiece to be welded (100). Each of the flow-deflecting protrusions (321) is frustoconical, and the small-diameter end face of the flow-deflecting protrusion (321) is close to the workpiece to be welded (100). The laser via (30) passes through both end faces of the flow-deflecting protrusion (321). And / or, an expansion cavity (320) is formed between adjacent blocking plates (32). And / or, a buffer space (111) is formed between the blocking plate (32) closest to the laser inlet (110) and the sealing cover (11).

4. The local vacuum laser welding apparatus according to claim 3, characterized in that, The diameter of each laser via (30) decreases along the incident direction.

5. The local vacuum laser welding apparatus according to claim 2, characterized in that, The mounting cylinder (31) is integrally formed with each of the blocking plates (32); and / or, the mounting cylinder (31) has a mounting flange (311) extending radially outward therefrom, the vacuum cylinder (12) is welded to the mounting flange (311) at one end near the workpiece to be welded (100), and the mounting flange (311) is detachably connected to the sealing cover (11).

6. The local vacuum laser welding apparatus according to claim 5, characterized in that, It also includes an air curtain dust blocking component, which includes an air curtain output component (41) located inside the vacuum cylinder (12) and on the side of the laser protection lens (2) near the laser inlet (110).

7. The local vacuum laser welding apparatus according to claim 6, characterized in that, A vacuum port (121) is formed on the wall of the vacuum cylinder (12). The vacuum port (121) is controllably connected to an external vacuum suction system, and the vacuum port (121) is located between the smoke and dust blocking component (3) and the air curtain dust blocking component.

8. The local vacuum laser welding apparatus according to claim 6, characterized in that, The air curtain output component (41) includes a flow divider ring (411) and a plurality of airflow nozzles (412) spaced along the circumferential direction of the flow divider ring (411) on the inner ring wall of the flow divider ring (411). An annular air passage (410) is formed inside the flow divider ring (411), and each of the airflow nozzles (412) is connected to the annular air passage (410). The laser protection lens (2) is assembled on the vacuum cylinder (12) via a lens holder (21), and the flow divider ring (411) is detachably assembled on the lens holder (21).

9. The local vacuum laser welding apparatus according to claim 8, characterized in that, The jet direction of each of the airflow nozzles (412) forms an angle α with the central axis of the flow divider ring (411), where 10°≤a≤35°; and / or, the cross-section of the nozzle (412) is rectangular.

10. The local vacuum laser welding apparatus according to claim 2, characterized in that, The diameter of the laser via (30) is not less than 2 mm and not more than 30 mm; and / or the distance between two adjacent blocking plates (32) is not less than 10 mm and not more than 40 mm; and / or the surface roughness Ra of the dust blocking component (3) is ≤0.8 μm; and / or there are not less than three blocking plates (32).

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