Coaxial multi-atmosphere water guided laser processing device

Abstract

The application discloses a coaxial multi-atmosphere water guide laser processing device, which comprises a laser generating module, a light-water coupling module, a protective gas flow generating module and a composite nozzle assembly. The light-water coupling module couples the water jet and the laser by total reflection to form a laser water jet. The protective gas flow generating module comprises a first protective gas flow generating module and at least one second protective gas flow generating module, and can generate multiple layers of coaxial protective gas flows. The first protective gas flow spirally surrounds the outside of the laser water jet, and the second protective gas flow further surrounds the outside of the first protective gas flow. The composite nozzle assembly is composed of a first nozzle and at least one second nozzle which are coaxially nested from inside to outside. Finally, the output is a coaxial composite jet composed of the laser water jet and the multiple layers of protective gas flows. The application solves the technical problems that are difficult to simultaneously realize efficient water drainage, prevent molten material from splashing back and maintain the stability of the water jet in the prior art.

Description

Technical Field

[0001] This invention relates to the field of water-guided laser technology, and in particular to a coaxial multi-atmosphere water-guided laser processing apparatus. Background Technology

[0002] In the field of water-guided laser processing, existing technologies often employ a single protective airflow to stabilize the water jet and isolate it from air. However, this single airflow has significant limitations when dealing with complex processing environments: its ability to drain accumulated water is limited, affecting processing efficiency; it provides insufficient protection against molten pool splashes and plasma, easily leading to contamination of optical components and disturbance of the water jet; more importantly, a single airflow cannot simultaneously achieve multiple objectives such as tightly enveloping the water jet to stabilize it, effectively removing liquid from the processing area, and actively creating a specific chemical reaction atmosphere in the working area, thus limiting the application of water-guided laser technology in high-quality, high-efficiency, and special material processing. Various solutions have been proposed in existing technologies to improve the stability and processing performance of the water jet. For example, Chinese Patent CN117086477B discloses a water-guided laser processing device with multiple water-gas composite modes. By optimizing the composite structure of water and gas to extend the stable section length of the water jet, the annular water curtain causes water accumulation on the workpiece surface, which is difficult to drain in time. When the laser enters the water accumulation area, it undergoes diffusion, resulting in uneven energy distribution and affecting processing quality and cutting depth. Summary of the Invention

[0003] The main objective of this invention is to propose a coaxial multi-atmosphere water-guided laser processing device, which aims to solve the technical problems in the prior art of simultaneously achieving efficient drainage, preventing molten material back splashing, and maintaining stable water jet.

[0004] To achieve the above objectives, the first aspect of the present invention provides a coaxial multi-atmosphere water-guided laser processing apparatus, comprising a laser generating module, an optical-water coupling module, a protective gas flow generating module, and a composite nozzle assembly; the laser generating module is used to emit a laser beam; the optical-water coupling module includes a liquid nozzle configured to couple a water jet with the laser beam via total internal reflection to form a laser-water jet; the protective gas flow generating module includes a first protective gas flow generating module and at least one second protective gas flow generating module; the first protective gas flow generating module is used to form a first protective gas flow coaxial with the laser-water jet and spirally surrounding the laser-water jet; the at least one second protective gas flow generating module is used to form a first protective gas flow coaxial with the laser-water jet and spirally surrounding the laser-water jet; the first ... The airflow generation module forms at least one layer of second protective airflow coaxial with the first protective airflow and surrounding the outside of the first protective airflow; the composite nozzle assembly includes a first nozzle and at least one second nozzle, the number of second nozzles corresponding to the number of second protective airflow generation modules; the first nozzle is connected to the outlet of the first protective airflow generation module; the at least one second nozzle is sequentially coaxially sleeved on the outer periphery of the first nozzle and respectively connected to the outlet of the corresponding second protective airflow generation module, so that the final output of the composite nozzle assembly is the laser water jet, the first protective airflow and the at least one layer of second protective airflow sequentially and coaxially distributed from the inside to the outside.

[0005] Preferably, the first protective airflow generation module includes a first gas mixing chamber, a second gas mixing chamber, and a gas-water coupling chamber coaxially arranged from the outside to the inside; the first gas mixing chamber is used to receive the input first protective gas; the second gas mixing chamber is connected to the first gas mixing chamber and is used to organize the gas from the first gas mixing chamber into a primary rotating airflow; the gas-water coupling chamber is connected to the second gas mixing chamber and is used to receive the primary rotating airflow and accelerate it to form the first protective airflow; the liquid nozzle is disposed at the center of the gas-water coupling chamber.

[0006] Preferably, the first protective airflow generation module further includes a first air inlet channel and a plurality of first spiral guide channels; the first air inlet channel is connected to the first gas mixing chamber and is used to input a first protective gas into the first gas mixing chamber; the inlet ends of the plurality of first spiral guide channels are connected to the first gas mixing chamber, and the outlet ends are connected to the second gas mixing chamber; the plurality of first spiral guide channels are evenly distributed around the axis of the gas-water coupling chamber, and the outlet direction is configured such that when the gas from the first gas mixing chamber enters the second gas mixing chamber, it generates a rotational motion around the axis, forming the primary rotating airflow.

[0007] Preferably, the first protective airflow generation module further includes a plurality of second spiral guide channels; the inlet end of the plurality of second spiral guide channels is connected to the second gas mixing chamber, and the outlet end is connected to the gas-water coupling chamber; the plurality of second spiral guide channels are evenly distributed around the axis of the gas-water coupling chamber, and the outlet direction is configured such that when the primary rotating airflow from the second gas mixing chamber enters the gas-water coupling chamber, it generates a rotational motion around the axis, forming the first protective airflow.

[0008] Preferably, the plurality of second spiral guide channels are located at a first height in the axial direction of the gas-water coupling cavity, and the plurality of first spiral guide channels are located at a second height in the axial direction below the first height, so that the gas undergoes at least two rotational accelerations as it flows toward the outlet; the flow cross-sectional area of ​​the second spiral guide channel is smaller than that of the first spiral guide channel, and is used to accelerate the airflow.

[0009] Preferably, the inlet end of the second spiral guide channel has a tapered guide structure, the inlet cross-section of which is larger than the flow cross-section of the channel body, for smoothly guiding the airflow in.

[0010] Preferably, an annular protective baffle is also coaxially arranged inside the gas-water coupling cavity; the annular protective baffle is arranged around the liquid nozzle and includes, from top to bottom, a connected inverted conical guide section and a cylindrical isolation section, with the lower end extending to a height lower than the outlet of the second spiral guide channel, thereby separating the inner laser water jet channel and the outer first protective gas flow channel inside the gas-water coupling cavity.

[0011] Preferably, the photo-water coupling module further includes a water inlet channel, a first mixing chamber, a second mixing chamber, an annular baffle, and an annular flow gap; the water inlet channel is connected to the annular first mixing chamber; the annular baffle is coaxially disposed between the first mixing chamber and the second mixing chamber, and the annular flow gap is formed between the annular baffle and the top wall of the first mixing chamber; the second mixing chamber is connected to the first mixing chamber through the annular flow gap, so that the liquid enters the second mixing chamber in a circumferentially symmetrical manner; the liquid nozzle is coaxially disposed at the center of the second mixing chamber.

[0012] Preferably, the at least one second protective airflow generating module includes a second air inlet channel, a third gas mixing chamber, multiple third guide channels, and a fourth gas mixing chamber; the second air inlet channel is connected to the third gas mixing chamber and is used to input a second protective gas into the third gas mixing chamber; the third gas mixing chamber is an annular cavity, and its axis coincides with the axis of the first protective airflow generating module; the inlet ends of the multiple third guide channels are connected to the third gas mixing chamber, and the outlet ends are connected to the fourth gas mixing chamber; the fourth gas mixing chamber is an annular cavity, coaxially sleeved on the outside of the first protective airflow generating module, and connected to the corresponding second nozzle through an annular airflow outlet channel.

[0013] Preferably, there are multiple second protective airflow generating modules; the fourth gas mixing chamber and the corresponding second nozzle of each second protective airflow generating module are coaxially nested in sequence, and the second air inlet channel of each second protective airflow generating module is independently set to input the same or different types of protective gas respectively; the composite nozzle assembly is configured to output a coaxial composite jet consisting of the laser water jet, the first protective airflow, and the multi-layer second protective airflow provided by the multiple independent second protective airflow generating modules, from the inside out.

[0014] The multifunctional adjustable water-guided laser head provided by this invention achieves graded and coordinated protection by setting up multiple coaxial and independently adjustable protective airflows, improving the efficiency of removing accumulated liquid and contaminants in the processing area and the isolation and protection effect on the core water jet. By forming a spiral flow in the innermost protective airflow to utilize its centrifugal and pumping effects, and by providing a stable gas sheath constraint for the outer airflow, the anti-interference capability and transmission stability of the water jet are improved. By adopting an inner and outer airflow division strategy, the inner layer can use a small flow rate of high-cost inert gas while the outer layer uses a large flow rate of low-cost gas, which significantly reduces the gas usage cost while ensuring an inert atmosphere in the processing area. The modular multi-layer nested design allows for flexible configuration of the number, type, and parameters of the protective airflow layers, improving the adaptability of the device to different material processing requirements and complex process environments.

[0015] Furthermore, this invention improves the formation efficiency and flow field stability of the rotating airflow by guiding and organizing the airflow step by step through a three-stage coaxial cavity; it enhances the energy concentration of the first protective airflow and its tight envelopment effect on the water jet by finally accelerating the rotating airflow within the air-water coupling cavity; it improves the efficiency and circumferential uniformity of the primary rotating airflow by efficiently generating rotating airflow using multiple first spiral guide channels with specific configurations in the outlet directions; it enhances the rotation intensity, flow order, and stable envelopment effect on the water jet by setting a second spiral guide channel to further organize and accelerate the rotating airflow; it improves the accumulation of rotational kinetic energy and airflow stability by setting the two-stage spiral guide channels at different axial heights to allow the gas to undergo two rotational accelerations; it increases the axial velocity and impact force of the final protective airflow by making the cross-sectional area of ​​the second spiral guide channel smaller than that of the first channel to accelerate the airflow; and it smoothly guides the airflow by setting a tapered guide structure at the inlet of the second spiral guide channel. The system incorporates several key technologies: First, it guides the flow, reducing flow loss and improving airflow quality. Second, it sets the outlet direction of the two-stage spiral guide channel tangentially, enhancing the formation efficiency and final intensity of the rotating airflow. Third, it establishes an axisymmetric flow channel composed of an annular baffle and a flow gap, ensuring circumferential symmetrical entry of the liquid into the second mixing chamber and improving the uniformity of water supply to the liquid nozzle. Fourth, it forces the liquid to smoothly transition through the annular gap, optimizing the flow field before the nozzle and improving the stability and symmetry of the formed water jet. Fifth, it uses an annular protective baffle with a combination of inverted conical and cylindrical structures within the air-water coupling cavity to physically isolate the laser water jet into a undisturbed and stable transmission channel, improving the water jet's forming quality and transmission stability. Sixth, it improves the uniformity and output stability of the outer protective airflow through independent gas path and cavity structure design. Finally, it enables flexible combination and separate control of multiple protective airflows through coaxial nesting of multiple modules and independent gas supply settings, improving the device's adaptability and economy to different processing atmosphere requirements.

[0016] In summary, the coaxial multi-atmosphere water-guided laser processing device proposed in this invention solves the technical problems in the prior art of simultaneously achieving efficient drainage, preventing molten material back splashing, and maintaining stable water jet. Attached Figure Description

[0017] 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.

[0018] Figure 1 These are schematic diagrams of the top and front views of a coaxial multi-atmosphere water-guided laser processing device according to the present invention; Figure 2 for Figure 1 Sectional view at point A in the middle; Figure 3 for Figure 1 Sectional view at point B; Figure 4 for Figure 3 Sectional view at point C; Figure 5 for Figure 3 Sectional view at point D; Figure 6 This is a schematic diagram of the base of a coaxial multi-atmosphere water-guided laser processing device according to the present invention; Figure 7 for Figure 2 Enlarged diagram of point E in the middle.

[0019] In the attached diagram: 1-Laser generating module, 2-Optical-water coupling module, 21-Liquid nozzle, 22-Water inlet channel, 23-First mixing chamber, 24-Second mixing chamber, 25-Annular baffle, 26-Annular flow gap 3-Protective airflow generation module, 31-First protective airflow generation module, 311-First gas mixing chamber, 312-Second gas mixing chamber, 313-Gas-water coupling chamber, 314-First air inlet channel, 315-First spiral guide channel, 316-Second spiral guide channel, 317-Annular protective baffle, 32-Second protective airflow generation module, 321-Second air inlet channel, 322-Third gas mixing chamber, 323-Third guide channel, 324-Fourth gas mixing chamber. 4-Composite nozzle assembly, 41-First nozzle, 42-Second nozzle.

[0020] 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

[0021] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] It should be noted that if the embodiments of the present invention involve directional indicators, such as up, down, left, right, front, back, etc., the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0023] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0024] like Figures 1 to 7 As shown, a coaxial multi-atmosphere water-guided laser processing device includes a laser generating module 1, an optical-water coupling module 2, a protective gas flow generating module 3, and a composite nozzle assembly 4. The laser generating module 1 emits a laser beam. The optical-water coupling module 2 includes a liquid nozzle 21 configured to couple a water jet with the laser beam via total internal reflection, forming a laser-water jet. The protective gas flow generating module 3 includes a first protective gas flow generating module 31 and at least one second protective gas flow generating module 32. The first protective gas flow generating module 31 forms a first protective gas flow that is coaxial with the laser-water jet and spirally surrounds it. The at least one second protective gas flow generating module 32 forms a first protective gas flow that is coaxial with the laser-water jet and spirally surrounds it. Block 32 forms at least one layer of second protective airflow coaxial with the first protective airflow and surrounding the outside of the first protective airflow; the composite nozzle assembly 4 includes a first nozzle 41 and at least one second nozzle 42, the number of second nozzles 42 corresponding to the number of second protective airflow generating modules 32; the first nozzle 41 is connected to the outlet of the first protective airflow generating module 31; at least one second nozzle 42 is sequentially coaxially sleeved on the outer periphery of the first nozzle 41 and is respectively connected to the outlet of the corresponding second protective airflow generating module 32, so that the final output of the composite nozzle assembly is a laser water jet, a first protective airflow and at least one layer of second protective airflow sequentially and coaxially distributed from the inside to the outside.

[0025] For details, see Figures 1 to 3In a specific embodiment of the present invention, the laser generating module 1 serves as an energy source, typically using a fiber laser or a solid-state laser. After collimation and focusing by a focusing lens group, the laser beam is guided to the top center inlet of the optical-water coupling module 2. The main body of the optical-water coupling module 2 is a sealed coupling cavity. The upper part of the cavity is provided with a laser entrance window, which is typically made of corrosion-resistant and high-transmittance materials such as sapphire or diamond. After being focused by the focusing lens group, the laser beam passes vertically through the laser entrance window and enters the coupling cavity. A liquid nozzle 21 is integrated at the bottom of the coupling cavity, and the central axis of the liquid nozzle 21 is coaxial with the optical axis of the laser beam. The side wall of the coupling cavity of the optical-water coupling module 2 is provided with a water inlet channel 22. A high-pressure water pump pumps water into the cavity through the water inlet channel 22, and finally ejects it at high speed from the small hole at the end of the liquid nozzle 21, forming a stable and continuous cylindrical water jet. When the focal point of the laser beam converged by the laser generating module 1 falls at or slightly above the inlet of the liquid nozzle, the laser beam is confined within this thin water jet by total internal reflection, forming a laser water jet as if it were propagated in an optical fiber. The protective airflow generation module 3 is integrated downstream of the optical-water coupling module 2, specifically comprising a first protective airflow generation module 31 and at least one second protective airflow generation module 32. The first protective airflow generation module 31 is constructed around the outlet section of the liquid nozzle 21 at the center of the optical-water coupling module 2, and its function is to generate a first layer of protective airflow. This first layer of protective airflow is coaxial with the internal laser water jet and spirals around it, rotating in either clockwise or counterclockwise direction. There are one or more second protective airflow generation modules 32, coaxially mounted around the first protective airflow generation module 31. Each second protective airflow generation module can independently generate a layer of protective airflow, which is also coaxial with the internal laser water jet and surrounds the previous layer. The gas type, pressure, flow rate, and rotation state of each layer of airflow can be independently controlled. The composite nozzle assembly 4 is the final forming and output component of these coaxial multi-layer jets, including a first nozzle 41 and at least one second nozzle 42 in a nested structure; the innermost first nozzle 41 is directly connected to the outlet of the first protective airflow generation module 31, which is used to constrain and guide the final shape of the first layer of spiral protective airflow containing the laser water jet; one or more second nozzles 42 are coaxially sleeved on the outside of the first nozzle 41, and each second nozzle 42 is connected to the outlet of its corresponding second protective airflow generation module 32; finally, what is output from the end of the composite nozzle assembly is a coaxial composite processing jet composed of the laser water jet, the spirally surrounding first layer of protective airflow, and one or more outer layers of second protective airflow from the inside out.

[0026] It should be noted that the first protective gas flow is usually made of inert gas such as helium. Since the first protective gas flow is in direct contact with the laser water jet, its main function is to provide an inert processing atmosphere and initially stabilize the water jet. Due to the high cost of helium, its flow rate is strictly limited. This invention innovatively incorporates at least one layer of secondary protective airflow at the periphery. This secondary protective airflow can utilize inexpensive compressed air or nitrogen. The core logic lies in forming a robust barrier through the outer layer of inexpensive yet high-flow-rate gas. This effectively resists external environmental interference and constrains the shape of the inner helium flow field, thereby significantly reducing the direct energy and mass exchange between the expensive internal helium and the chaotic external environment. This allows the inner helium to play its crucial role in a relatively calm and protected environment with a smaller required flow rate. Ultimately, this significantly extends the stable transmission length of the laser water jet and enhances the robustness of the overall processing without significantly increasing costs. Simultaneously, one or more secondary protective airflows at the outer layer can form a wider gas curtain, further isolating the environment, assisting in dispersing water in the processing area and propelling splashes radially away, or introducing specific reactive / protective gases to create a locally controllable processing atmosphere.

[0027] Understandably, this invention uses relatively inexpensive gases such as compressed air as the outer second protective airflow to effectively protect the expensive inner first protective airflow medium, significantly reducing the consumption and operating costs of high-cost gases. The outer protective airflow, with its high flow rate and velocity, provides a more reliable physical isolation and anti-interference barrier for the inner airflow and laser water jet, improving the stability of the core processing jet. Through the division of labor and synergy between the inner and outer airflows, the inner helium ensures an inert environment in the contact area with the jet, while the outer compressed air resists external disturbances and maintains flow field stability, improving system economy while ensuring processing quality. The independently adjustable multi-layered airflow structure allows the inner gas velocity and flow rate to be optimized to precisely meet isolation requirements, while the outer gas can flexibly employ higher flow rates to enhance the overall protection effect, improving the flexibility of process adjustment and overall efficiency.

[0028] Based on the above-described technical solution of the present invention, those skilled in the art can make corresponding equivalent improvements according to the application scenario. For example, the gas input to the outermost second protective airflow generation module can be replaced with nitrogen to obtain a drier and cleaner protective environment than compressed air; or the helium used in the first protective airflow generation module can be replaced with other inert gases such as argon to adapt to the processing atmosphere requirements of different materials; or the structure of the second protective airflow generation module can be designed to generate spiral airflow to further enhance the ability to resist and eliminate external disturbances.

[0029] Preferably, the first protective airflow generation module 31 includes a first gas mixing chamber 311, a second gas mixing chamber 312, and a gas-water coupling chamber 313 coaxially arranged from the outside to the inside; the first gas mixing chamber 311 is used to receive the input first protective gas; the second gas mixing chamber 312 is connected to the first gas mixing chamber 311 and is used to organize the gas from the first gas mixing chamber 311 into a primary rotating airflow; the gas-water coupling chamber 313 is connected to the second gas mixing chamber 312 and is used to receive the primary rotating airflow and accelerate the formation of the first protective airflow; the liquid nozzle 21 is disposed at the center of the gas-water coupling chamber 313.

[0030] For details, see Figures 1 to 3 In a specific embodiment of the present invention, the first gas mixing chamber 311 is an annular sealed chamber that receives a first protective gas, such as helium, from a gas source through an independent first air inlet channel, serving to initially collect and stabilize the incoming gas pressure. The second gas mixing chamber 312 is also annular and is coaxially nested inside the first gas mixing chamber 311. A specific airflow channel structure connects the first gas mixing chamber 311 and the second gas mixing chamber 312, allowing the gas entering the second gas mixing chamber 312 from the first gas mixing chamber 311 to be organized and guided within the second gas mixing chamber 312, forming a primary rotating airflow that rotates around a common axis. This can be achieved in various ways, such as by setting a guide structure at the connection point or by using the shape of the chamber itself to guide the gas to generate a tangential velocity component. Then, the primary rotating airflow enters the innermost gas-water coupling chamber 313 from the second gas mixing chamber 312 through a specific airflow channel structure. The center of the gas-water coupling chamber 313 is a liquid nozzle 21. Within the gas-water coupling cavity 313, the rotating airflow is further constrained and accelerated by a specific airflow channel structure, forming a first layer of protective airflow that tightly spirals around the laser water jet. This airflow is then finally ejected from the liquid nozzle 21 through the outlet of the gas-water coupling cavity 313. This cavity design, which nests from the outside in and organizes the gas flow in stages, allows the airflow to rotate in the intermediate chamber, ultimately achieving spiral output and providing a dynamic and stable inert atmosphere protection for the core processing area.

[0031] Understandably, this invention, by setting up a second gas mixing chamber and organizing the gas from the first gas mixing chamber into a rotating airflow within it, gives the output first protective airflow a spiral-forward characteristic, improving its ability to dissipate accumulated liquid and contaminants in the processing area and maintain the stability of the water jet; through the nested design of three coaxial cavities, the gas flow is guided and shaped step by step, ultimately achieving acceleration and focused output of the rotating airflow in the gas-water coupling chamber, improving the directionality, cohesion, and fit of the protective airflow to the water jet; by generating a spiral-forward protective airflow, its centrifugal effect and pumping action are utilized to improve the efficiency of local atmosphere replacement and slag removal in the processing area.

[0032] Preferably, the first protective airflow generation module 31 further includes a first air intake channel 314 and a plurality of first spiral guide channels 315; the first air intake channel 314 is connected to the first gas mixing chamber 311 and is used to input the first protective gas into the first gas mixing chamber 311; the inlet end of the plurality of first spiral guide channels 315 is connected to the first gas mixing chamber 311, and the outlet end is connected to the second gas mixing chamber 312; the plurality of first spiral guide channels 315 are evenly distributed around the axis of the gas-water coupling chamber 313, and the outlet direction is configured such that when the gas from the first gas mixing chamber 311 enters the second gas mixing chamber 312, it generates a rotational motion around the axis, forming a primary rotating airflow.

[0033] For details, see Figure 3 and Figure 4 In a specific embodiment of the present invention, the first air inlet channel 314 is an independent pipe interface used to connect an external gas source to the first gas mixing chamber 311, and to deliver a first protective gas, such as helium, into the first gas mixing chamber 311 for preliminary convergence and pressure balancing; the inlet ends of the plurality of first spiral guide channels 315 are all open on the inner peripheral wall of the first gas mixing chamber 311, and the outlet ends are connected to the inner second gas mixing chamber 312; in this embodiment, the plurality of first spiral guide channels 315 are not simple radial through holes, but are evenly distributed in the circumferential direction around the core axis of the entire device, namely the axis of the gas-water coupling chamber 313, for example, four, six or eight channels can be set; the path of each first spiral guide channel 315 from the inlet to the outlet is designed to have a specific orientation, and the outlet direction is not pointing to the radial direction of the second gas mixing chamber 312, but is approximately tangential to the circular peripheral wall of the second gas mixing chamber 312, or in other words, the airflow enters the annular space of the second gas mixing chamber 312 with a significant tangential velocity component. When gas is injected from the first gas mixing chamber 311 into the second gas mixing chamber 312 through these outlets arranged approximately tangentially, multiple gas streams converge and interact within the annular chamber, jointly driving the gas medium within the chamber to rotate around the central axis as a whole. This efficiently organizes what might have been a chaotic gas flow into a robust and uniform primary rotating gas flow. This design ensures that the rotation is initiated before the gas flow enters the final acceleration phase, guaranteeing the full development of the rotation and a uniform distribution of momentum in the circumferential direction.

[0034] Understandably, this invention efficiently converts the airflow from the first gas mixing chamber into a rotating flow by setting multiple first spiral guide channels with specific outlet directions, thereby improving the reliability and rotation intensity of the initial rotating airflow formation. By uniformly distributing the multiple first spiral guide channels around the axis, it ensures that the flow rate and direction of the airflow injected into the second gas mixing chamber from all directions are consistent, improving the circumferential uniformity and stability of the formed initial rotating airflow and avoiding the occurrence of asymmetric vortices. By using the spiral guide channels to pre-organize the airflow, a stable vortex is established before entering the subsequent chambers, which improves the efficiency of airflow organization and may reduce the total pressure loss compared to a design that generates rotation only in the final chamber.

[0035] Preferably, the first protective airflow generation module 31 further includes a plurality of second spiral guide channels 316; the inlet end of the plurality of second spiral guide channels 316 is connected to the second gas mixing chamber 312, and the outlet end is connected to the gas-water coupling chamber 313; the plurality of second spiral guide channels 316 are evenly distributed around the axis of the gas-water coupling chamber 313, and the outlet direction is configured such that when the primary rotating airflow from the second gas mixing chamber 312 enters the gas-water coupling chamber 313, it generates a rotational motion around the axis to form the first protective airflow.

[0036] For details, see Figure 3 and Figure 5 In a specific embodiment of the present invention, a plurality of second spiral guide channels 316 constitute the path for airflow from the second gas mixing chamber 312 to the gas-water coupling chamber 313. The inlet end of each second spiral guide channel 316 is opened on the inner wall surface of the second gas mixing chamber 312 to receive the primary rotating airflow that has been initially formed therein, and the outlet end leads to the innermost gas-water coupling chamber 313. Multiple second spiral guide channels 316 are evenly arranged in the circumferential direction around the central axis of the gas-water coupling cavity 313. For example, four, six, or eight channels can be set to ensure the balance of circumferential input. The path from the inlet to the outlet is designed to have a specific orientation. The outlet of the channel does not simply point to the radial center of the gas-water coupling cavity 313, but is designed so that the direction of the ejected gas flow is approximately tangential to the annular circumferential wall of the gas-water coupling cavity 313. When the primary rotating gas flow with rotational momentum is distributed from the second gas mixing cavity 312 into the multiple second spiral guide channels 316, the gas flow is constrained in the channel and guided according to the set tangential direction. Subsequently, multiple tangential jets with the same direction are synchronously injected into the annular space of the gas-water coupling cavity 313 from the outlet of these channels. They converge and merge in the gas-water coupling cavity 313 and jointly drive all the gas medium in the cavity to generate a composite gas flow that rotates at high speed and stably around the axis, which constitutes the first protective gas flow for tightly wrapping the laser water jet.

[0037] Understandably, this invention, by setting multiple second spiral guide channels to reorganize and guide the primary rotating airflow, transmits the rotational motion and ultimately shapes it within the air-water coupling cavity, thereby increasing the intensity of the rotational state of the first protective airflow. By configuring the outlet direction of the second spiral guide channels to generate tangential jets, it ensures that the rotational momentum is efficiently injected into the final chamber, improving the energy concentration and flow order of the formed spiral airflow. By utilizing the second spiral guide channels to ultimately shape the airflow pattern, the output first protective airflow has a clear and consistent rotational direction, improving its coaxial envelopment stability of the water jet and its protective effect on the processing area.

[0038] Preferably, the plurality of second spiral guide channels 316 are located at a first height in the axial direction of the gas-water coupling cavity 313, and the plurality of first spiral guide channels 315 are located at a second height in the axial direction below the first height, so that the gas undergoes at least two rotational accelerations in the process of flowing toward the outlet; the flow cross-sectional area of ​​the second spiral guide channel 316 is smaller than the flow cross-sectional area of ​​the first spiral guide channel 315, and is used to accelerate the airflow.

[0039] For details, see Figures 2 to 5 In one specific embodiment of the present invention, a plurality of first spiral guide channels 315 are located at a relatively low second height position in the axial direction of the overall structure, guiding the gas from the first gas mixing chamber 311 into the second gas mixing chamber 312 in a roughly tangential manner, thereby exciting and forming a primary rotating airflow in the lower region of the chamber; subsequently, the gas flows in rotation, and a plurality of second spiral guide channels 316 are arranged at a first height position in the axial direction above the outlet of the first spiral guide channels 315; after flowing through the second gas mixing chamber 312, the primary rotating airflow reaches this first height and enters the final gas-water coupling chamber 313 through the plurality of second spiral guide channels 316. Through the staggered arrangement in axial height, the gas undergoes a process of being given rotational momentum twice in space from low to high at different positions from entering the device to the final output, constituting at least two stages of rotational acceleration. Furthermore, the flow cross-sectional area of ​​the second spiral guide channel 316 is smaller than that of the first spiral guide channel 315. When the airflow flows out from the relatively spacious first spiral guide channel 315 and enters the relatively narrow second spiral guide channel 316, the airflow velocity will be increased according to the principles of fluid mechanics. Through the design of the difference in cross-sectional area, combined with the axial height difference, the gradual organization and acceleration of the rotating airflow are achieved.

[0040] Understandably, this invention, by setting multiple first spiral guide channels and multiple second spiral guide channels at different axial heights, allows the gas to undergo two rotational processes sequentially along its flow path, thereby improving the accumulation of rotational kinetic energy and airflow stability. By designing the flow cross-sectional area of ​​the second spiral guide channel to be smaller than that of the first spiral guide channel, the airflow undergoing primary rotation is accelerated, increasing the axial velocity and impact force of the final output airflow. Through the synergistic design of the axial height difference and the flow cross-sectional area difference, the separation and optimization of airflow rotation and acceleration in space and time are achieved, improving the reliability of the airflow shaping process and the overall performance of the final protected airflow.

[0041] Preferably, the outlet direction of the first spiral guide channel 315 is tangentially arranged relative to the peripheral wall of the second gas mixing chamber 312; the outlet direction of the second spiral guide channel 316 is tangentially arranged relative to the peripheral wall of the gas-water coupling chamber 313.

[0042] Understandably, this invention improves the efficiency and reliability of primary rotating airflow formation by efficiently stimulating rotational motion through tangential outlets; and enhances rotational momentum through secondary tangential injection, thereby increasing the rotational intensity and concentration of the first protective airflow.

[0043] Preferably, the inlet end of the second spiral guide channel 316 has a tapered guide structure, the inlet cross section of which is larger than the flow cross section of the channel body, for smoothly guiding the airflow in.

[0044] For details, see Figure 5 In a specific embodiment of the present invention, the inlet end of the second spiral guide channel 316 forms a tapered guide structure. The inlet cross-section of this guide structure has a large opening, and its area is larger than the flow cross-sectional area of ​​the main body of the channel. Starting from the inlet, the inner wall of the channel smoothly converges inward, and its outline can be trumpet-shaped, conical, or a specific streamlined curved surface, eventually transitioning to the standard flow cross-sectional size of the channel body. The tapered guide structure allows the primary rotating airflow entering from the second gas mixing chamber 312 to smoothly enter the inlet of the guide channel with a larger angle range and a more relaxed tolerance, instead of directly impacting the sized orifice edge. Under the guidance of the tapered section, the flow direction of the airflow is gradually adjusted to be consistent with the axis of the channel body, the streamline is straightened, and the flow cross-section is also steadily reduced, thereby reducing the eddies, flow separation, and local pressure loss caused by the sudden contraction and sharp change in flow direction at the inlet. This allows the airflow to enter and fill the entire second spiral guide channel 316 more efficiently and smoothly, laying a good foundation for subsequent acceleration within the channel and ultimately ejection as a high-quality tangential jet.

[0045] Preferably, an annular protective baffle 317 is also coaxially arranged inside the gas-water coupling cavity 313; the annular protective baffle 317 is arranged around the liquid nozzle 21, and includes a connected inverted conical guide section and a cylindrical isolation section from top to bottom, with the lower end extending to a height lower than the outlet of the second spiral guide channel 316, thereby separating the inner laser water jet channel and the outer first protective airflow channel inside the gas-water coupling cavity 313.

[0046] For details, see Figure 2 and Figure 3 In a specific embodiment of the present invention, the annular protective baffle 317 is coaxially sleeved outside the liquid nozzle 21. The entire structure consists of two continuous sections from top to bottom. The upper section is an inverted conical guide section, whose inner wall is a cone with a gradually decreasing inner diameter in the downstream direction. The top of this cone is sealed to the top structure of the gas-water coupling cavity 313. The lower section is a cylindrical isolation section, whose inner wall is a vertical cylindrical surface, smoothly connected to the lower edge of the inverted conical guide section, forming a continuous inner wall of the flow channel. The lower edge of the cylindrical isolation section is axially lower than the axial positions of all outlets of the second spiral guide channels 316. When the high-speed rotating airflow is ejected from the outlet of the second spiral guide channel 316, it flows along the outer conical surface of the inverted conical guide section, guiding the tangential airflow to smoothly change into a more axial flow and converge downstream. The straightened airflow then mainly spirals downwards along the outer wall of the cylindrical isolation section. Meanwhile, after the laser water jet is formed at the outlet of the liquid nozzle 21, it flows downward through the upper space formed by the inner wall of the inverted conical guide section and the outer wall of the liquid nozzle, and then enters the lower annular channel formed by the inner wall of the cylindrical isolation section and the outer wall of the liquid nozzle, and finally outputs stably.

[0047] Understandably, this invention provides a smooth turning guide surface for the high-speed rotating airflow on the outside by setting an inverted conical guide section, thereby reducing turbulence and energy loss caused by airflow impact; by connecting a cylindrical isolation section and extending its lower end below the airflow inlet, a geometrically stable physical isolation channel is constructed for the laser water jet, which is free from the direct action of external airflow shear force, thereby improving the stability of the water jet.

[0048] Preferably, the photo-water coupling module 2 further includes a water inlet channel 22, a first mixing chamber 23, a second mixing chamber 24, an annular baffle 25, and an annular flow gap 26; the water inlet channel 22 is connected to the annular first mixing chamber 23; the annular baffle 25 is coaxially disposed between the first mixing chamber 23 and the second mixing chamber 24, and an annular flow gap 26 is formed between the annular baffle 25 and the top wall of the first mixing chamber 23; the second mixing chamber 24 is connected to the first mixing chamber 23 through the annular flow gap 26, so that the liquid enters the second mixing chamber 24 in a circumferentially symmetrical manner; the liquid nozzle 21 is coaxially disposed at the center of the second mixing chamber 24.

[0049] For details, see Figure 1 , Figure 2 , Figure 3 and Figure 7 In a specific embodiment of the present invention, the water inlet channel 22 is used to guide the water flow pumped by the high-pressure water pump into a first mixing chamber 23 arranged around the central axis. The first mixing chamber 23 is an annular cavity, which provides space for the initial mixing of the water flow and the circumferential pressure equalization. Inside the first mixing chamber 23, a second mixing chamber 24 is coaxially arranged. The two chambers are physically separated by an annular baffle 25. The inner wall of the annular baffle 25 is the boundary of the second mixing chamber 24. Between the upper edge of the annular baffle 25 and the top wall of the first mixing chamber 23, a continuous annular flow gap 26 of a specific height is maintained, so that the liquid in the first mixing chamber 23 cannot directly flow into the second mixing chamber 24, but must flow upward uniformly, over the upper edge of the annular baffle 25, and then flow into the second mixing chamber 24 inside it evenly and symmetrically in the circumferential direction through the annular flow gap 26. This flow path forces the liquid to undergo thorough circumferential mixing and equilibration before entering the final chamber, effectively eliminating potential velocity or pressure unevenness caused by a single inlet channel. After undergoing a second mixing and stabilization in the second mixing chamber 24, the liquid finally ejects a stable and symmetrical cylindrical water jet from the liquid nozzle 21 located at the bottom center of the second mixing chamber 24, laying a crucial fluid dynamic foundation for the subsequent efficient total internal reflection coupling of the laser.

[0050] Understandably, this invention, by setting up a first annular mixing chamber and a second mixing chamber separated by an annular baffle, forces the water flow to undergo two distribution and mixing processes within the chambers before entering the final nozzle, significantly improving the pressure and velocity uniformity of the incoming flow in the circumferential direction. By utilizing the annular flow gap formed between the annular baffle and the top wall of the chamber as the only connecting path, the water flow is forced to smoothly transition to the second mixing chamber in a circumferentially axisymmetric manner, effectively eliminating asymmetric flow and eddies, and improving the initial stability and symmetry of the water jet. By optimizing the flow field quality before the nozzle, an ideal water-medium waveguide is provided for the total reflection coupling of the laser beam, reducing laser energy scattering and coupling efficiency loss caused by water flow disturbance.

[0051] Preferably, at least one second protective airflow generating module 32 includes a second air inlet channel 321, a third gas mixing chamber 322, multiple third guide channels 323, and a fourth gas mixing chamber 324; the second air inlet channel 321 is connected to the third gas mixing chamber 322 and is used to input the second protective gas into the third gas mixing chamber 322; the third gas mixing chamber 322 is an annular cavity, and its axis coincides with the axis of the first protective airflow generating module 31; the inlet ends of the multiple third guide channels 323 are connected to the third gas mixing chamber 322, and the outlet ends are connected to the fourth gas mixing chamber 324; the fourth gas mixing chamber 324 is an annular cavity, coaxially sleeved on the outside of the first protective airflow generating module 31, and connected to the corresponding second nozzle 42 through an annular airflow outlet channel.

[0052] For details, see Figures 1 to 2 In a specific embodiment of the present invention, the second air intake channel 321 is an independent pipe with its inlet connected to an external gas source for inputting a second protective gas, such as compressed air or nitrogen. The outlet of the second air intake channel 321 is connected to the third gas mixing chamber 322. The third gas mixing chamber 322 is an annular sealed chamber whose axis coincides with the core axis of the entire device, namely the axis of the first protective airflow generation module 31. The inlet ends of multiple third guide channels 323 are evenly opened on the inner peripheral wall of the third gas mixing chamber 322 for receiving the gas in the chamber, and the outlet ends are all connected to the fourth gas mixing chamber 324. The fourth gas mixing chamber 324 is another annular chamber located radially inside the third gas mixing chamber 322 and coaxially sleeved on the entire outer side of the first protective airflow generation module 31. The fourth gas mixing chamber 324 is sealed to the corresponding second nozzle 42 through an annular outlet airflow channel. During operation, the second protective gas enters the third gas mixing chamber 322 through the second intake channel 321 for initial pressure equalization and distribution. Then, it is guided into the fourth gas mixing chamber 324 through multiple third guide channels 323, where it is further mixed and stabilized. Finally, it is output from the second nozzle 42 through the annular outlet channel, forming a second protective gas curtain that wraps around the outer side of the inner first protective gas flow.

[0053] Understandably, this invention achieves independent gas supply and initial pressure stabilization for the outer protective gas by setting up an independent second air intake channel and a third gas mixing chamber, thereby improving the independence and stability of airflow parameter control. By utilizing multiple third guide channels to guide the gas from the third gas mixing chamber to the inner fourth gas mixing chamber, the airflow is redistributed and rectified, improving the uniformity of the airflow before entering the final output channel. By adopting a structure in which the fourth gas mixing chamber is coaxially sleeved on the outside of the inner module and connected to the annular air outlet channel, it is ensured that the outer protective airflow can be output in the form of a coaxial and uniform annular air curtain, improving its isolation effect against the external environment and its protective performance against the inner airflow.

[0054] Preferably, there are multiple second protective airflow generation modules 32; the fourth gas mixing chamber 324 of each second protective airflow generation module 32 and its corresponding second nozzle are coaxially nested in sequence, and the second air inlet channel 321 of each second protective airflow generation module 32 is independently set to input the same or different types of protective gas respectively; the composite nozzle assembly is configured to output a coaxial composite jet of laser water jet, first protective airflow and multi-layer second protective airflow provided by multiple independent second protective airflow generation modules 32, from the inside to the outside.

[0055] Understandably, this invention significantly enhances the multi-layered airflow output by setting up multiple independent second protective airflow generation modules in a coaxial nested manner, thereby significantly improving the multiple isolation and resistance capabilities against external environmental disturbances and increasing the purity and stability of the atmosphere in the core processing area. By configuring an independent air intake channel for each outer module to achieve independent control of airflow parameters, it provides the ability to flexibly match and optimize between cost, protective performance, and special atmosphere requirements, thereby improving process adaptability and economy. By outputting a clearly structured multi-layered coaxial composite jet, the high-flow-rate, high-speed airflow of the outer layer provides reliable protection for the expensive, low-speed airflow of the inner layer, reducing the consumption of high-cost protective gases while ensuring processing quality.

[0056] In specific implementation, the device of the present invention can be operated according to the following steps: First, the high-pressure water supply system is started, so that deionized water enters the coupling cavity through the water inlet channel of the photo-water coupling module and is ejected at high speed from the end of the liquid nozzle to form a stable and continuous cylindrical water jet; then, the gas supply system is started, and a first protective gas, such as helium, is introduced into the first gas mixing cavity through the first air inlet channel of the first protective airflow generation module. After passing through multiple first spiral guide channels, it is organized into a rotating airflow and enters the second gas mixing cavity to form a primary vortex. After passing through multiple second spiral guide channels, it is further accelerated and regulated, and finally output from the gas-water coupling cavity to form a tightly spiraled, inert first protective airflow around the outer layer of the water jet; then, through the independent second air inlet channels of one or more second protective airflow generation modules, a second protective gas, such as compressed air or nitrogen, is introduced into the corresponding third gas mixing cavity. After each layer of gas is distributed through its respective third guide channel, it is stabilized in the fourth gas mixing cavity and finally output from the corresponding second nozzle through the annular outlet channel to form one or more second protective airflows coaxially sleeved on the outside of the first protective airflow.

[0057] In the specific implementation process, when selecting the gas type for each layer of protective airflow, one can refer to the gas physical properties (such as dynamic viscosity, density, solubility, etc.) listed in authoritative physics handbooks such as the *American Institute of Physics Handbook* for comprehensive consideration and selection. It is particularly important to note that some gases (such as chlorine, hydrogen bromide, etc.) may have a certain solubility in water jets, some gases are flammable (such as hydrogen, acetylene), and others may be toxic or pose health hazards (such as chlorine, sulfur dioxide). When selecting such gases, caution must be exercised and appropriate safety precautions must be taken. In contrast, gases such as helium, argon, nitrogen, and carbon dioxide have the characteristics of high stability and good safety. Therefore, in the multi-layer coaxial protective airflow design of this invention, the inner first protective airflow typically uses high-purity inert gases such as helium or argon to ensure the purity and chemical inertness of the atmosphere in the contact area with the laser water jet. The outer one or more second protective airflows can use lower-cost gases such as nitrogen, compressed air, or argon, or even gases with other properties can be selected according to specific process requirements (such as auxiliary cooling, oxidation suppression, or the introduction of controllable reactions), thereby achieving an optimal balance between safety, economy, and process adaptability. In terms of airflow organization strategy, to improve the protective effect of the outer airflow on the inner airflow, a gas with a dynamic viscosity and density greater than or equal to the inner first protective gas is typically selected as the second protective gas, for example, compressed air is used to protect helium. Simultaneously, by adjusting the supply pressure, the average axial velocity component of the outer second protective airflow is made greater than or equal to that of the inner first protective airflow, thereby utilizing the high-speed outer airflow to constrain the inner flow field and more effectively eliminate environmental interference. Regarding the startup sequence, a sequential startup strategy can be adopted. First, the inner first protective airflow is started. After a preset delay time, allowing the flow field to fully develop and stabilize, the outer second protective airflow is then started. This delay time is the minimum time interval required for the first spiral airflow to establish a stable flow field. This avoids the outer airflow starting too early and impacting the still unstable inner flow field. Once the water jet and the inner and outer multi-layer spiral protective airflows together form a stable multi-atmosphere composite jet, the laser generation module is activated to emit a focused laser beam. The laser beam is precisely aligned with the liquid nozzle inlet and coupled into the center of the water jet via total internal reflection, forming a laser-water jet. Finally, a coaxial composite processing flow, consisting of the laser-water jet, the first spiral protective airflow, and one or more layers of second protective airflow, is output from the composite nozzle assembly and acts on the workpiece surface.

[0058] The multifunctional adjustable water-guided laser head provided by this invention achieves graded and coordinated protection by setting up multiple coaxial and independently adjustable protective airflows, improving the efficiency of removing accumulated liquid and contaminants in the processing area and the isolation and protection effect on the core water jet. By forming a spiral flow in the innermost protective airflow to utilize its centrifugal and pumping effects, and by providing a stable gas sheath constraint for the outer airflow, the anti-interference capability and transmission stability of the water jet are improved. By adopting an inner and outer airflow division strategy, the inner layer can use a small flow rate of high-cost inert gas while the outer layer uses a large flow rate of low-cost gas, which significantly reduces the gas usage cost while ensuring an inert atmosphere in the processing area. The modular multi-layer nested design allows for flexible configuration of the number, type, and parameters of the protective airflow layers, improving the adaptability of the device to different material processing requirements and complex process environments.

[0059] Furthermore, this invention improves the formation efficiency and flow field stability of the rotating airflow by guiding and organizing the airflow step by step through a three-stage coaxial cavity; it enhances the energy concentration of the first protective airflow and its tight envelopment effect on the water jet by finally accelerating the rotating airflow within the air-water coupling cavity; it improves the efficiency and circumferential uniformity of the primary rotating airflow by efficiently generating rotating airflow using multiple first spiral guide channels with specific configurations in the outlet directions; it enhances the rotation intensity, flow order, and stable envelopment effect on the water jet by setting a second spiral guide channel to further organize and accelerate the rotating airflow; it improves the accumulation of rotational kinetic energy and airflow stability by setting the two-stage spiral guide channels at different axial heights to allow the gas to undergo two rotational accelerations; it increases the axial velocity and impact force of the final protective airflow by making the cross-sectional area of ​​the second spiral guide channel smaller than that of the first channel to accelerate the airflow; and it smoothly guides the airflow by setting a tapered guide structure at the inlet of the second spiral guide channel. The system incorporates several key technologies: First, it guides the flow, reducing flow loss and improving airflow quality. Second, it sets the outlet direction of the two-stage spiral guide channel tangentially, enhancing the formation efficiency and final intensity of the rotating airflow. Third, it establishes an axisymmetric flow channel composed of an annular baffle and a flow gap, ensuring circumferential symmetrical entry of the liquid into the second mixing chamber and improving the uniformity of water supply to the liquid nozzle. Fourth, it forces the liquid to smoothly transition through the annular gap, optimizing the flow field before the nozzle and improving the stability and symmetry of the formed water jet. Fifth, it uses an annular protective baffle with a combination of inverted conical and cylindrical structures within the air-water coupling cavity to physically isolate the laser water jet into a undisturbed and stable transmission channel, improving the water jet's forming quality and transmission stability. Sixth, it improves the uniformity and output stability of the outer protective airflow through independent gas path and cavity structure design. Finally, it enables flexible combination and separate control of multiple protective airflows through coaxial nesting of multiple modules and independent gas supply settings, improving the device's adaptability and economy to different processing atmosphere requirements.

[0060] In summary, the coaxial multi-atmosphere water-guided laser processing device proposed in this invention solves the technical problems in the prior art of simultaneously achieving efficient drainage, preventing molten material back splashing, and maintaining stable water jet.

[0061] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A coaxial multi-atmosphere water-guided laser processing device, characterized in that, include: Laser generating module (1), used to emit laser beam; The optical-water coupling module (2) includes a liquid nozzle (21) configured to couple the water jet with the laser beam by total internal reflection to form a laser water jet; The protective airflow generation module (3) includes a first protective airflow generation module (31) and at least one second protective airflow generation module (32); the first protective airflow generation module (31) is used to form a first protective airflow that is coaxial with the laser water jet and spirally surrounds the laser water jet; the at least one second protective airflow generation module (32) forms at least one layer of second protective airflow that is coaxial with the first protective airflow and surrounds the outside of the first protective airflow; the first protective airflow generation module (31) includes a first gas mixing chamber (311), a second gas mixing chamber (312), and a gas-water mixture that are coaxially arranged from the outside to the inside. The coupling cavity (313) is further comprising a first air inlet channel (314) and a plurality of first spiral guide channels (315); the first air inlet channel (314) is connected to the first gas mixing cavity (311) and is used to input the first protective gas into the first gas mixing cavity (311); the inlet end of the plurality of first spiral guide channels (315) is connected to the first gas mixing cavity (311), and the outlet end is connected to the second gas mixing cavity (312); the plurality of first spiral guide channels (315) are evenly distributed around the axis of the gas-water coupling cavity (313), and the outlet end is... When gas from the first gas mixing chamber (311) enters the second gas mixing chamber (312), a rotational motion is generated around the axis, forming a primary rotating airflow. The first protective airflow generation module (31) also includes a plurality of second spiral guide channels (316). The inlet ends of the plurality of second spiral guide channels (316) are connected to the second gas mixing chamber (312), and the outlet ends are connected to the gas-water coupling chamber (313). The plurality of second spiral guide channels (316) are evenly distributed around the axis of the gas-water coupling chamber (313), and the outlet direction is configured to allow gas from the second gas mixing chamber (312) to enter the second gas mixing chamber (312). When the primary rotating airflow from the mixing chamber (312) enters the gas-water coupling chamber (313), it generates a rotational motion around the axis, forming the first protective airflow; a plurality of second spiral guide channels (316) are located at a first height in the axial direction of the gas-water coupling chamber (313), and a plurality of first spiral guide channels (315) are located at a second height below the first height in the axial direction, so that the gas undergoes at least two rotational accelerations in the process of flowing to the outlet; the flow cross-sectional area of ​​the second spiral guide channel (316) is smaller than the flow cross-sectional area of ​​the first spiral guide channel (315), and is used to accelerate the airflow; The composite nozzle assembly (4) includes a first nozzle (41) and at least one second nozzle (42), the number of the second nozzles (42) corresponding to the number of the second protective airflow generating modules (32); the first nozzle (41) is connected to the outlet of the first protective airflow generating module (31); the at least one second nozzle (42) is sequentially coaxially sleeved on the outer periphery of the first nozzle (41) and connected to the outlet of the corresponding second protective airflow generating module (32), so that the final output of the composite nozzle assembly is the laser water jet, the first protective airflow and the at least one layer of second protective airflow sequentially and coaxially distributed from the inside to the outside.

2. The coaxial multi-atmosphere water-guided laser processing apparatus as described in claim 1, characterized in that, The first gas mixing chamber (311) is used to receive the input first protective gas; the second gas mixing chamber (312) is connected to the first gas mixing chamber (311) and is used to organize the gas from the first gas mixing chamber (311) into a primary rotating airflow; the gas-water coupling chamber (313) is connected to the second gas mixing chamber (312) and is used to receive the primary rotating airflow and accelerate it to form the first protective airflow; the liquid nozzle (21) is located at the center of the gas-water coupling chamber (313).

3. The coaxial multi-atmosphere water-guided laser processing apparatus as described in claim 1, characterized in that, The inlet end of the second spiral guide channel (316) has a tapered guide structure, the inlet cross section of which is larger than the flow cross section of the channel body, for smoothly guiding the airflow in.

4. The coaxial multi-atmosphere water-guided laser processing apparatus as described in claim 1 or claim 3, characterized in that, An annular protective baffle (317) is also coaxially arranged inside the gas-water coupling cavity (313); the annular protective baffle (317) is arranged around the liquid nozzle (21), and includes a connected inverted conical guide section and a cylindrical isolation section from top to bottom, with the lower end extending to a height lower than the outlet of the second spiral guide channel (316), thereby separating the inner laser water jet channel and the outer first protective airflow channel inside the gas-water coupling cavity (313).

5. The coaxial multi-atmosphere water-guided laser processing apparatus as described in any one of claims 1 to 4, characterized in that, The photo-water coupling module (2) further includes a water inlet channel (22), a first mixing chamber (23), a second mixing chamber (24), an annular baffle (25), and an annular flow gap (26); the water inlet channel (22) is connected to the annular first mixing chamber (23); the annular baffle (25) is coaxially disposed between the first mixing chamber (23) and the second mixing chamber (24), and the annular flow gap (26) is formed between the annular baffle (25) and the top wall of the first mixing chamber (23); the second mixing chamber (24) is connected to the first mixing chamber (23) through the annular flow gap (26) so that the liquid enters the second mixing chamber (24) in a circumferentially symmetrical manner; the liquid nozzle (21) is coaxially disposed at the center of the second mixing chamber (24).

6. The coaxial multi-atmosphere water-guided laser processing apparatus as described in any one of claims 1 to 4, characterized in that, The at least one second protective airflow generating module (32) includes a second air inlet channel (321), a third gas mixing chamber (322), a plurality of third guide channels (323), and a fourth gas mixing chamber (324); the second air inlet channel (321) is connected to the third gas mixing chamber (322) and is used to input a second protective gas into the third gas mixing chamber (322); the third gas mixing chamber (322) is an annular cavity and its axis coincides with the axis of the first protective airflow generating module (31); the inlet end of the plurality of third guide channels (323) is connected to the third gas mixing chamber (322), and the outlet end is connected to the fourth gas mixing chamber (324); the fourth gas mixing chamber (324) is an annular cavity, coaxially sleeved on the outside of the first protective airflow generating module (31), and connected to the corresponding second nozzle (42) through an annular airflow outlet channel.

7. The coaxial multi-atmosphere water-guided laser processing apparatus as described in claim 6, characterized in that, The number of the second protective airflow generation modules (32) is multiple; the fourth gas mixing chamber (324) of each second protective airflow generation module (32) and its corresponding second nozzle are arranged coaxially in sequence, and the second air inlet channel (321) of each second protective airflow generation module (32) is independently arranged to input the same or different types of protective gas respectively; the composite nozzle assembly is configured to output a coaxial composite jet of the laser water jet, the first protective airflow and the multi-layer second protective airflow provided by multiple independent second protective airflow generation modules (32) from the inside to the outside.

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