Blowing head and laser welding equipment

Abstract

The invention provides a blowing head and laser welding equipment, the blowing head comprises a body, the body is provided with a laser channel in a penetrating mode, the laser channel is provided with a light inlet end and a light outlet end, and a laser beam is transmitted to the light outlet end from the light inlet end; the protective glass is positioned on one side of the light inlet end; a blowing channel used for conveying protective gas into the laser channel is arranged on the side wall of the body in a penetrating mode. The end face, close to the light outlet end, of the body is provided with a spherical reflecting face which is concavely arranged towards the light inlet end, the spherical reflecting face and a space defined by a welded workpiece form a heat storage space, and the laser channel is communicated into the heat storage space. According to the method, the influence of protective gas on cooling of a welding spot area can be reduced, the laser absorption rate of a welded part is increased, and the welding depth and quality are guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of laser welding, and in particular to a blowing head and a laser welding device. Background Art

[0002] During the laser processing, smoke and dust will be generated at the solder joints of the workpieces to be welded. In order to prevent the smoke and dust from affecting the focusing lens, usually in the transmission direction of the laser beam, a protective glass is arranged downstream of the focusing lens to block the smoke and dust escaping in the reverse direction along the laser transmission direction, thereby effectively protecting the focusing lens and ensuring the effective focusing of the laser beam. Similarly, the protective glass also needs to be kept clean to ensure the smooth penetration of the laser beam. In the prior art, a blowing head is usually arranged at the light-emitting end of the laser welding head. The inside of the blowing head is hollow and has a laser channel. The blowing head is externally connected to a protective gas source, and a gas flow is formed by introducing a protective gas into the laser channel. On the one hand, the smoke and dust escaping in the reverse direction along the laser transmission direction (entering the laser channel from the welding area) can be dispersed, avoiding the pollution of the protective glass by this part of the dust and ensuring the light transmittance of the protective glass; on the other hand, the protective gas also disperses the air in the outlet area of the blowing head, that is, the laser welding area, to prevent the solder joints from being oxidized.

[0003] However, when the protective gas overflows from the light-emitting end, it inevitably impacts the solder joint area, resulting in a decrease in the temperature of the solder joint area, a decrease in the laser absorption rate, and further affecting the welding depth and quality. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the first object of the present invention is to provide a blowing head, which can effectively reduce the influence of the protective gas on the temperature reduction of the solder joint area, improve the laser absorption rate of the workpiece to be welded, and ensure the welding depth and quality.

[0005] The second object of the present invention is to provide a laser welding device, which can ensure that the solder joints are not oxidized, and at the same time can reduce the influence of the protective gas on the temperature reduction of the solder joint area, and ensure the welding depth and quality.

[0006] The embodiments of the present invention are realized by the following technical solutions:

[0007] A blowing head includes a body. A laser channel is disposed through the body. The laser channel has a light input end and a light output end, and a laser beam is transmitted from the light input end to the light output end. A protective glass is located on one side of the light input end. A blowing channel for delivering a protective gas into the laser channel is disposed through the side wall of the body. An end face of the body near the light output end is configured with a spherical reflecting surface recessed toward the light input end. A heat storage space is formed by the space defined by the spherical reflecting surface and the workpiece to be welded. The laser channel communicates with the heat storage space. Part of the light reflected by the workpiece to be welded is re-reflected back to the solder joint area under the action of the spherical reflecting surface, greatly improving the heating effect of the solder joint area, thereby reducing the influence of the protective gas on the temperature reduction of the solder joint area, enhancing the absorption rate of the workpiece to be welded to the laser beam, and achieving deep and stable welding of high-reflective materials such as copper. After the protective gas is discharged from the laser channel through the light output end, its flow path becomes wider. Therefore, the flow rate of the protective gas entering the heat storage space slows down and expands rapidly to fill the heat storage space, and then diffuses around, so that the air in this area, that is, around the solder joint, is dispelled, effectively preventing the solder joint from being oxidized. At the same time, after the speed of the protective gas slows down, the impact force on the solder joint can be reduced, further reducing the temperature reduction effect of the protective gas on the solder joint, and ensuring the welding depth and quality.

[0008] According to a preferred embodiment, the distance between the center of the spherical reflecting surface and the optical axis center line of the laser beam is 0 - 2 mm.

[0009] According to a preferred embodiment, the center of the spherical reflecting surface is on the optical axis center line of the laser beam.

[0010] According to a preferred embodiment, the center of the spherical reflecting surface coincides with the focus of the laser beam.

[0011] According to a preferred embodiment, the radius of the spherical reflecting surface is 5 mm - 10 mm.

[0012] According to a preferred embodiment, the body includes an air inlet part and a nozzle connected to each other. The spherical reflecting surface is disposed on the nozzle. The nozzle is rotatably connected to the air inlet part.

[0013] According to a preferred embodiment, the center of the spherical reflecting surface does not coincide with the optical axis center line of the laser beam.

[0014] According to a preferred embodiment, the blowing channel includes a first blowing channel and a second blowing channel. The first blowing channel is between the second blowing channel and the light input end. The first blowing channel is inclined toward the direction close to the light input end, and the second blowing channel is inclined toward the direction close to the light output end.

[0015] According to a preferred embodiment, the laser channel is coaxial with the laser beam.

[0016] A laser welding device includes a laser head and the aforementioned air-blowing head. Along the transmission direction of the laser beam in the laser head, a focusing lens and the protective glass are sequentially arranged, and the air-blowing head is assembled on the laser output head and is downstream of the protective glass. This laser welding device can ensure that the solder joints are not oxidized, and at the same time, it can reduce the temperature-lowering effect of the protective gas on the solder joint area, ensuring the welding depth and quality.

[0017] According to a preferred embodiment, the wavelength of the laser beam is less than 550 nm. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 A three-dimensional structural schematic diagram of the air-blowing head provided by an embodiment of the present invention;

[0020] Figure 2 A cross-sectional view of the assembly structure of the laser head and the air-blowing head provided by an embodiment of the present invention;

[0021] Figure 3 A schematic diagram of the flow state of the protective gas in the assembly structure of the laser head and the air-blowing head provided by an embodiment of the present invention;

[0022] Figure 4 A three-dimensional structural schematic diagram of the air-blowing head after assembling the adapter provided by an embodiment of the present invention;

[0023] Figure 5 A cross-sectional view of the air-blowing head provided by another embodiment of the present invention;

[0024] Figure 6 For Figure 5 A schematic diagram of the light spot projected on the workpiece to be welded after the air-blowing head is assembled with the laser head as shown.

[0025] Icon: 1. Body; 10. Laser channel; 101. Light input end; 102. Light output end; 103. Confluence acceleration cavity; 11. Air intake part; 111. First air blowing channel; 112. Second air blowing channel; 12. Nozzle; 120. Spherical reflecting surface; 1200. Center of the sphere; 1201. Auxiliary light spot; 121. Heat storage space; 122. Driven gear; 13. Adapter; 14. Bearing; 15. Motor; 151. Driving gear; 2. Laser head; 21. Focusing lens; 22. Protective glass; 3. Laser beam; 30. Optical axis center line; 4. Workpiece to be welded; 41. Welding point; 410. Welding light spot; a. First air flow beam; a1. First branch; a2. Second branch; b. Second air flow beam; c. Combined air flow; A. First convergence point; B. Second convergence point. Detailed implementation mode

[0026] For better understanding and implementation, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0027] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0029] Please refer to Figures 1 to 4 , a blowing head, which is assembled at the end of the laser head 2, is used to protect the protective glass 22 and at the same time divert the protective gas to the area of the welding point 41 during the processing of the laser welding head. For the convenience of description, as Figure 2 Figure 3 shown, the blowing head is matched with the laser head 2, and the sectional view of the assembly structure of the two is used for explanation. It should be noted that the laser head 2 has a channel for the transmission of the laser beam 3, and a focusing lens 21 and a protective glass 22 are sequentially assembled in this channel along the transmission direction of the laser beam 3.

[0030] Specifically, the gas blowing head includes a body 1. The body 1 is provided with a laser channel 10 running through it. The laser channel 10 is coaxial with the laser beam 3. The laser channel 10 has a light input end 101 and a light output end 102. The laser beam 3 is transmitted from the light input end 101 to the light output end 102. The protective glass 22 is located on one side of the light input end 101. A gas blowing channel for delivering protective gas into the laser channel 10 is provided through the side wall of the body 1. The end face of the body 1 near the light output end 102 is configured with a spherical reflecting surface 120 recessed towards the light input end 101. The space formed by the spherical reflecting surface 120 and the welded workpiece 4 constitutes a heat storage space 121. The laser channel 10 communicates with the heat storage space 121. During the welding process, part of the light reflected by the welded workpiece 4 is re-reflected back to the solder joint 41 area under the action of the spherical reflecting surface 120, greatly improving the heating effect of the solder joint 41 area, thereby reducing the influence of the protective gas on the temperature reduction of the solder joint 41 area, enhancing the absorption rate of the welded workpiece 4 to the laser beam 3, and achieving deep and stable welding of high-reflection materials such as copper.

[0031] Further, as Figure 2 and Figure 3 shown, in the horizontal direction, the width of the heat storage space 121 is greater than the width of the outlet end. This means that after the protective gas is discharged from the laser channel 10 through the light output end 102, its flow channel becomes wider. Therefore, the flow rate of the protective gas entering the heat storage space 121 slows down and expands rapidly to fill the heat storage space 121, and then diffuses around, so that the air around the solder joint 41, that is, in this area, is dispersed, effectively preventing the solder joint 41 from being oxidized. At the same time, after the speed of the protective gas slows down, the impact force on the solder joint 41 can be reduced, further reducing the temperature reduction effect of the protective gas on the solder joint 41 and ensuring the welding depth and quality.

[0032] Optionally, the gas includes but is not limited to nitrogen or inert gas.

[0033] Of course, in some embodiments, the laser beam 3 and the laser channel 10 may also be non-coaxial, and it is only necessary that their extending directions are parallel.

[0034] In some embodiments, the distance between the center of the sphere 1200 of the spherical reflecting surface 120 and the optical axis center line 30 of the laser beam 3 is 0 - 2 mm. Preferably, the distance between the center of the sphere 1200 of the spherical reflecting surface 120 and the optical axis center line 30 of the laser beam 3 is 0 - 1 mm. Further preferably, the distance between the center of the sphere 1200 of the spherical reflecting surface 120 and the optical axis center line 30 of the laser beam 3 is 0 mm, that is, the center of the sphere 1200 of the spherical reflecting surface 120 is on the optical axis center line 30 of the laser beam 3. In this way, the focus of the light beam reflected by the spherical reflecting surface 120 is closer to the center of the solder joint 41.

[0035] Furthermore, the center 1200 of the spherical reflecting surface 120 coincides with the focus of the laser beam 3. This makes the focusing point of the light beam reflected by the spherical reflecting surface 120 coincide with the center of the solder joint 41, achieving an optimal heating effect.

[0036] In this embodiment, the radius of the spherical reflecting surface 120 is between 5 mm and 10 mm. Preferably, the radius of the spherical reflecting surface 120 is 7.5 mm.

[0037] As Figure 2 and Figure 3 shown, the blowing channel includes a first blowing channel 111 and a second blowing channel 112. The first blowing channel 111 is located between the second blowing channel 112 and the light incident end 101; the first blowing channel 111 is inclined in the direction close to the light incident end 101, and the second blowing channel 112 is inclined in the direction close to the light exit end 102. In this embodiment, the laser beam 3 from the laser head 2 is focused by the focusing lens 21, and its focus is on the side of the light exit end 102. Under the laser welding condition, the focus of the laser beam 3 projects onto the workpiece 4 to be welded and generates smoke and dust. Part of the smoke and dust enters the laser channel 10 through the light exit end 102 and diffuses. This part of the smoke and dust will not only absorb the energy of the laser beam 3 and affect the welding quality, but also has the risk of moving towards the light incident end 101 and polluting the protective glass 22. In order to prevent the smoke and dust from entering the laser channel 10 through the light exit end 102 and effectively discharge the smoke and dust entering the laser channel 10 to prevent the pollution of the protective glass 22, protective gas is continuously input into the laser channel 10 through the first blowing channel 111 and the second blowing channel 112 respectively. Since the first blowing channel 111 is inclined in the direction close to the light incident end 101 and the second blowing channel 112 is inclined in the direction close to the light exit end 102, as Figure 3As shown in the figure, the shielding gas input through the first gas blowing channel 111 flows towards the light output end 102, i.e., the area where the shielding glass 22 is located, and finally impacts the side surface of the shielding glass 22 facing the light output end 102. After being blocked by the shielding glass 22, this part of the shielding gas forms an air flow layer near the side surface of the shielding glass 22 facing the light output end 102, and moves towards the light output end 102 along at least the inner wall of the laser channel 10 and is discharged from the laser channel 10. During this process, if there is some soot attached to the shielding glass 22, this part of the soot will be removed by the shielding gas input through the first gas blowing channel 111 impacting the shielding glass 22, and the shielding glass 22 can be effectively cooled during this process; for this part of the soot that is removed, as well as the soot suspended in the laser channel 10, they are blocked by the air flow layer and cannot adhere to the shielding glass 22; at the same time, when the shielding gas moves downward and is discharged from the laser channel 10, the soot in the laser channel 10 moves towards the light output end 102 following the shielding gas and is discharged. During the process of discharging the shielding gas at the light output end 102, on the one hand, the shielding gas can prevent the soot from entering the laser channel 10 through the light output end 102, and on the other hand, it can effectively disperse the air in the solder joint 41 area of the workpiece 4 to be welded, preventing the solder joint 41 from oxidizing.

[0038] Further, the shielding gas entering the laser channel 10 through the second gas blowing channel 112 flows towards the light output end 102. It can be understood that the shielding gas entering the laser channel 10 through the first gas blowing channel 111 and the second gas blowing channel 112 is discharged through the light output end 102. Therefore, the shielding gas in the laser channel 10 converges at least at the light output end 102. The shielding gas input into the laser channel 10 through the second gas blowing channel 112, on the one hand, can supplement the shielding gas input into the laser channel 10 through the first gas blowing channel 111 to ensure that the solder joint 41 area of the workpiece 4 to be welded is not oxidized; on the other hand, it can accelerate the shielding gas that enters the laser channel 10 through the first gas blowing channel 111 and flows between the second gas blowing channel 112 and the light output end 102, thereby forming a low-pressure environment in this area of the laser channel 10, which is more conducive to the soot in the laser channel 10 moving towards this area under the action of pressure and being discharged following the shielding gas.

[0039] Optionally, the inner diameter of the laser channel 10 gradually decreases from the light input end 101 to the light output end 102. With such a setting, from the light input end 101 to the light output end 102, that is, the flow channel area gradually decreases in the direction of the shielding gas discharge. Therefore, on the shielding gas discharge path, the shielding gas is in a gradually accelerating state, which also makes the pressure relatively small at the position near the light output end 102 in the laser channel 10, thus being more conducive to the soot in the laser channel 10 moving towards the light output end 102 and concentrating, which is beneficial to fully discharging the soot in the laser channel 10.

[0040] Preferably, the laser channel 10 is a rotary cavity.

[0041] Preferably, there are multiple first air blowing channels 111, and the multiple first air blowing channels 111 are evenly distributed at intervals along the circumferential direction of the laser channel 10. Further, there are multiple second air blowing channels 112, and the multiple second air blowing channels 112 are evenly distributed at intervals along the circumferential direction of the laser channel 10. In this embodiment, the number of the first air blowing channels 111 and the number of the second air blowing channels 112 are both four, so as to form a stable, uniform and sufficient protective gas flow in the laser channel 10.

[0042] As Figure 1 and Figure 4 shown, adapters 13 are assembled on both the first air blowing channel 111 and the second air blowing channel 112 for connecting to an external air source. In order to avoid interference during the assembly of the adapters 13, the first air blowing channel 111 and the second air blowing channel 112 are arranged in a circumferentially offset manner on the body 1. Of course, in another embodiment, if there is no interference during the assembly of the adapters 13, the first air blowing channel 111 and the second air blowing channel 112 may also be arranged in alignment or without offset in the circumferential direction of the body 1. As Figure 2 and Figure 3 shown, since this embodiment is a case where the first air blowing channel 111 and the second air blowing channel 112 are arranged in a circumferentially offset manner on the body 1, for the convenience of description, the air blowing head is constructed as a case where the first air blowing channel 111 and the second air blowing channel 112 are arranged in alignment or without offset in the circumferential direction of the body 1, and the first air blowing channel 111 is represented by a dotted line. It should be noted that whether the first air blowing channel 111 and the second air blowing channel 112 are circumferentially offset on the body 1 does not affect the flow mode of the protective gas in the laser channel 10, and only serves to avoid interference between the adapters 13.

[0043] As Figure 3As shown in the figure, it is defined that the protective gas entering the laser channel 10 through the first air blowing channel 111 forms a first air flow beam a. The multiple first air flow beams a corresponding to the multiple first air blowing channels 111 converge at the first convergence point A in the laser channel 10. After the first air flow beam a collides at the first convergence point A, it is divided into branches, mainly forming a first branch a1 and a second branch a2. Among them, the first branch a1 first diffuses and flows around the first convergence point A along the protective glass 22, and then moves along the inner walls of the laser head 2 and the air blowing head toward the light emitting end 102 side. The second branch a2 moves toward the light emitting end 102 side along a direction parallel to the optical axis center line 30 of the laser beam 3. The first branch a1 here can form an air flow layer on the side wall of the protective glass 22 facing the light emitting end 102, as well as on the inner walls of the laser head 2 and the air blowing head, effectively preventing soot from adhering, and at the same time being able to drive the soot in the area near the first branch a1 toward the light emitting end 102 side; the second branch a2 is closer to the optical axis center line 30 of the laser beam 3 than the first branch a1, that is, the second branch a2 is closer to the central area of the laser channel 10 than the first branch a1. Therefore, during the flow of the second branch a2 toward the light emitting end 102, a stable air flow is formed near the central area of the laser channel 10, and the soot existing in the vicinity of this area can be driven toward the light emitting end 102. Therefore, under the synergistic action of the first branch a1 and the second branch a2, it is possible to prevent soot from adhering to the protective glass 22, the laser head 2 and the laser channel 10 to the greatest extent, and at the same time a low pressure can be generated in the air flow path area, effectively driving the soot suspended in the laser channel 10 to move toward the light emitting end 102 and discharging it from the laser channel 10.

[0044] Preferably, the first convergence point A is on the optical axis center line 30 of the laser beam 3. More preferably, the first convergence point A is on the side of the protective glass 22 close to the light output end 102. Since the laser beam 3 is coaxial with the laser channel 10, when the first convergence point A is on the optical axis center line 30 of the laser beam 3 and on the side of the protective glass 22 close to the light output end 102, the first convergence point A coincides with the center point of the side of the protective glass 22 facing the light output end 102. Multiple first air flow beams a collide with each other at the first convergence point A and are blocked by the protective glass 22. Thus, the first air flow beam a can be split into a uniform first branch a1 and a uniform second branch a2 at the first convergence point A, making the air flow uniform throughout the laser channel 10, ensuring that the soot treatment degree in each space within the laser channel 10, especially in the spaces along the transmission path of the laser beam 3, is quite the same, to ensure the stability of the laser beam 3 and thus the stability of the welding quality. At the same time, the first convergence point A is at the center of the protective glass 22, making the cooling effect of the first air flow beam a on the central area of the protective glass 22 stable and effective. And the central area of the protective glass 22 coincides with the propagation path of the laser beam 3. Therefore, it can ensure that the protective glass 22 has a stable light transmission performance during welding, thereby ensuring the stability of the transmission of the laser beam 3 and further ensuring the stability of the welding quality.

[0045] It is defined that the protective gas entering the laser channel 10 through the second air blowing channel 112 forms a second air flow beam b. Multiple second air flow beams b corresponding to multiple second air blowing channels 112 converge at the second convergence point B within the laser channel 10. After the first air flow beam a collides and splits at the first convergence point A, it converges with the second air flow beam b at the second convergence point B to form a combined air flow c, which is discharged from the laser channel 10 through the light output end 102. Further, the second convergence point B is on the optical axis center line 30 of the laser beam 3. In this embodiment, preferably, both the first convergence point A and the second convergence point B are on the optical axis center line 30. Thus, a stable combined air flow c can be formed downstream of the second convergence point B to form a stable air flow blockage for the light output end 102, effectively preventing soot from entering the laser channel 10 from the light output end 102. At the same time, it can effectively discharge the soot entering the laser channel 10 and can evenly disperse the air in the area around the solder joint 41, making the protective gas evenly distributed in the solder joint 41 area and ensuring the stability of the welding quality.

[0046] Optionally, the area of the laser channel 10 close to the light output end 102 is conical, forming a confluence acceleration chamber 103. The small end of the confluence acceleration chamber 103 is the light output end 102. Through the gradually decreasing flow channel design, the flow velocity of the combined air flow c gradually increases, forming a low-pressure environment here to drive the soot in the laser channel 10 to be better discharged from the laser channel 10 through the light output end 102.

[0047] In this embodiment, the body 1 includes an air inlet portion 11 and a nozzle 12 which are connected to each other. The confluence acceleration chamber 103 is arranged in the nozzle 12. The first air blowing channel 111 and the second air blowing channel 112 are both arranged in the air inlet portion 11. The nozzle 12 is detachably connected to the air inlet portion 11. Preferably, the nozzle 12 is threadedly connected to the air inlet portion 11, which facilitates the replacement of the nozzle 12.

[0048] As Figure 2 shown, the included angle between the axis of the first air blowing channel 111 and the optical axis center line 30 of the laser beam 3 is α, and α = 30° - 60°. Preferably, α = 45°. The included angle between the axis of the second air blowing channel 112 and the optical axis center line 30 of the laser beam 3 is β, and β = 30° - 60°. Preferably, β = 45°.

[0049] As Figure 5 shown, the air blowing head provided for another embodiment is different from the air blowing head provided for the foregoing embodiment in the assembly form of the air inlet portion 11 and the nozzle 12, and the spherical reflecting surface 120 arranged on the nozzle 12. The structures other than this are the same, and the same structures will not be described herein again.

[0050] Specifically, as Figure 5 shown, the body 1 includes an air inlet portion 11 and a nozzle 12 which are connected to each other. The spherical reflecting surface 120 is arranged on the nozzle 12; the nozzle 12 is rotatably connected to the air inlet portion 11. Optionally, the nozzle 12 is rotatably connected to the air inlet portion 11 through a bearing 14. Further, the center of the sphere 1200 of the spherical reflecting surface 120 does not coincide with the optical axis center line 30 of the laser beam 3. Preferably, the center of the sphere 1200 of the spherical reflecting surface 120 is located on the workpiece 4 to be welded. Since the center of the sphere 1200 of the spherical reflecting surface 120 does not coincide with the optical axis center line 30 of the laser beam 3, that is, on the workpiece 4 to be welded, there is an offset radius between the center of the sphere 1200 and the welding spot 41. As Figure 6 shown, during the welding process, the laser beam 3 forms a welding light spot 410 at the welding spot 41. The light beam reflected by the workpiece 4 to be welded is reflected by the spherical reflecting surface 120 and focused at the center of the sphere 1200 to form an auxiliary light spot 1201. When the nozzle 12 rotates, the auxiliary light spot 1201 rotates around the welding light spot 410 with the offset radius as the radius to form an annular light spot, so as to preheat the annular light spot area, which is beneficial to improving the absorption rate of the workpiece 4 to be welded to the laser beam 3. At the same time, it helps to expand the molten pool area and reduce the amount of spatter, that is, the amount of soot, which can further reduce the probability of the protective glass 22 being contaminated and is beneficial to improving the welding depth and quality.

[0051] In this embodiment, the auxiliary light spot 1201 and the welding light spot 410 do not coincide.

[0052] In another embodiment, the auxiliary light spot 1201 and the welding light spot 410 at least partially coincide.

[0053] Optionally, the offset radius is D, where 0 < D ≤ 2 mm.

[0054] Preferably, 0 < D ≤ 1 mm. More preferably, D = 0.5 mm.

[0055] As Figure 5 shown, a motor 15 is provided on the outer wall of the air inlet portion 11. The drive shaft of the motor 15 is drivingly connected to a driving gear 151. A driven gear 122 meshing with the driving gear 151 is sleeved outside the nozzle 12. By driving the driving gear 151 with the motor 15, the nozzle 12 is driven to rotate through the driven gear 122. In this embodiment, the laser beam 3 is coaxial with the laser channel 10, and the rotation axis of the nozzle 12 coincides with the optical axis center line 30 of the laser beam 3.

[0056] As Figure 2 、 Figure 3 and Figure 5 shown, in this embodiment, a laser welding device is further provided, which includes a laser head 2 and the aforementioned air blowing head. Along the transmission direction of the laser beam 3 in the laser head 2, a focusing lens 21 and a protective glass 22 are sequentially arranged. The air blowing head is assembled on the light emitting head and is downstream of the protective glass 22. Based on the aforementioned air blowing head, the laser welding device can ensure that the solder joint 41 is not oxidized, and at the same time, can reduce the temperature reduction effect of the shielding gas on the solder joint 41 area, ensuring the welding depth and quality. In this embodiment, the laser beam 3 can be blue laser and / or infrared laser. It is better applied to the blue laser processing scenario, or in the processing scenario where the laser wavelength is less than 550 nm, so as to heat the solder joint 41 area of the workpiece 4 to be welded through the heat storage space 121, thereby improving the absorption rate of high reflectivity materials such as copper to short wavelength lasers and achieving a better welding effect. Of course, it can also be applied to the scenario of composite welding of red laser and blue laser.

[0057] The technical means disclosed in the solution of the present invention are not limited to the technical means disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present invention.

Claims

1. A blowing head, characterized in that, It includes a body (1) which is provided with a laser channel (10) running through it. The laser channel (10) has a light input end (101) and a light output end (102), and the laser beam (3) is transmitted from the light input end (101) to the light output end (102). The protective glass (22) is on the side of the light input end (101). A blowing channel for delivering protective gas into the laser channel (10) is provided through the side wall of the body (1). On the end face of the body (1) near the light output end (102), a spherical reflecting surface (120) recessed towards the light input end (101) is configured. The space defined by the spherical reflecting surface (120) and the workpiece to be welded (4) forms a heat storage space (121), and the laser channel (10) communicates with the heat storage space (121).

2. The blowing head according to claim 1, wherein, The distance between the center of the sphere (1200) of the spherical reflecting surface (120) and the optical axis center line (30) of the laser beam (3) is 0 - 2 mm.

3. The blowing head according to claim 1, characterized in that, The center of the sphere (1200) of the spherical reflecting surface (120) is on the optical axis center line (30) of the laser beam (3).

4. The air blowing head according to claim 1, wherein The center of the sphere (1200) of the spherical reflecting surface (120) coincides with the focus of the laser beam (3).

5. The blowing head according to claim 1, characterized in that, The radius of the spherical reflecting surface (120) is 5 mm - 10 mm.

6. The blowing head according to claim 1, wherein, The body (1) includes an air inlet part (11) and a nozzle (12) connected to each other, and the spherical reflecting surface (120) is arranged on the nozzle (12). The nozzle (12) is rotatably connected to the air inlet part (11).

7. The blowing head according to claim 6, characterized in that, The center of the sphere (1200) of the spherical reflecting surface (120) does not coincide with the optical axis center line (30) of the laser beam (3).

8. The blowing head according to claim 1, wherein, The blowing channel includes a first blowing channel (111) and a second blowing channel (112). The first blowing channel (111) is between the second blowing channel (112) and the light input end (101). The first blowing channel (111) is inclined towards the direction close to the light input end (101), and the second blowing channel (112) is inclined towards the direction close to the light output end (102).

9. The blowing head according to claim 1, characterized in that, The laser channel (10) is coaxial with the laser beam (3).

10. A laser welding device, characterized in that, It includes a laser head (2) and a blowing head as described in any one of claims 1 - 9. In the laser head (2), a focusing lens (21) and the protective glass (22) are sequentially arranged along the transmission direction of the laser beam (3), and the blowing head is assembled to the output laser head and is downstream of the protective glass (22).

11. The laser welding device according to claim 10, characterized in that, The wavelength of the laser beam (3) is less than 550 nm.

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