Ultrasonic assisted water-jet laser drilling device and method based on flow focusing

Abstract

This invention discloses an ultrasonic-assisted water-guided laser drilling device and method based on flow focusing, belonging to the field of water-guided laser processing technology. The device includes an optical path control module, an optical-liquid-gas coupling module, an ultrasonic assistance module, and a movement module. It employs a laser energy control method that uses in-situ monitoring and real-time adjustment during laser processing. A uniform laminar water jet is obtained through a multi-channel, distributed high-pressure water path design, and the coupling energy beam is controlled using flow-focused water-guided laser beam refinement technology. Ultrasonic vibration-assisted processing further improves the drilling quality. In summary, this invention can be used for the precision machining of hole structures in aerospace components, improving machining quality and thus enhancing the overall service performance of equipment.

Description

Technical Field

[0001] This invention belongs to the field of water-guided laser processing technology, specifically relating to an ultrasonic-assisted water-guided laser drilling device and method based on flow focusing. Background Technology

[0002] Water-guided laser, as an emerging precision machining technology, combines the advantages of laser processing with water jet cooling. It uses a "water beam fiber" to impact the workpiece surface to remove material. It has processing advantages such as a small heat-affected zone, no mechanical stress, and strong adaptability to workpiece surfaces, and can be widely used in the precision manufacturing of high-performance, difficult-to-machine parts in the aerospace field.

[0003] The prerequisite for realizing water-guided laser technology is the availability of a stable and collimated microjet. The smaller the diameter of the stable and collimated jet beam, the higher and more uniform the energy density, which is more conducive to obtaining a stable removal function. However, the current jet beam diameter often depends on the size of the fluid cavity nozzle. Nozzles with a diameter of less than 0.1 mm are expensive and prone to wear, so further exploration of the miniaturization technology of water-guided laser beams is needed. Flow focusing technology uses high-pressure gas flowing out coaxially to reduce the jet diameter, thereby obtaining a microjet with a diameter much smaller than that of the nozzle.

[0004] Aerospace components have a large number of holes, and drilling holes in difficult-to-machine materials can cause problems such as high thermal damage, low precision, large errors, and poor surface roughness. When machining blind holes, the tool has poor accessibility, coolant is difficult to inject, and chip blockage can easily cause drill bit breakage when machining deep and long holes.

[0005] Based on the above background, this invention proposes a water jet generation method based on the principle of flow focusing, which obtains a jet beam with a diameter much smaller than that of the nozzle. It uses a laser-jet fusion method to obtain a controllable coupled energy beam with a diameter on the order of ten micrometers. Furthermore, it employs ultrasonic-assisted machining technology to transmit high-frequency micro-impact to the machining area through a tool or workpiece, which helps to remove materials in a plastic manner, significantly reduces subsurface damage, obtains a smoother surface, improves machining quality, increases production efficiency, and effectively enhances the overall service performance of the equipment. Summary of the Invention

[0006] The purpose of this invention is to solve the above-mentioned problems and achieve efficient drilling of difficult-to-machine parts in the aerospace field. It provides an ultrasonic-assisted water-guided laser drilling device and method based on flow focusing.

[0007] The technical solution adopted in this invention is as follows:

[0008] The ultrasonic-assisted water-guided laser drilling device based on flow focusing includes: an optical path control module 1, an optical-liquid-gas coupling module 2, an ultrasonic auxiliary module 3, and a moving module 4.

[0009] The moving module 4 can control the up-and-down movement of the optical-liquid-gas coupling module 2, and can also control the horizontal movement of the ultrasonic auxiliary module 3 and the workpiece 41 above it.

[0010] The optical path control module 1 includes: a laser 11, a lens group, a reflector 14, a split mirror 15, a focusing double lens 16, a coupled observation CCD camera 17, and a monitoring and control group 18;

[0011] The laser beam emitted by the laser 11 is focused onto the laser window 23 of the optical-liquid-gas coupling module 2 by passing through a lens group, a reflector 14, a bipartite mirror 15, and a focusing double lens 16 in sequence.

[0012] The bipartite mirror 15 and the reflecting mirror 14 are arranged in parallel, and a coupled observation CCD camera 17 and a focusing double lens 16 are respectively arranged on the upper and lower sides of the bipartite mirror 15.

[0013] The monitoring and control group 18 includes an in-situ monitoring and acquisition unit 181, an industrial control computer 182, and a spatial light modulator 183;

[0014] The in-situ monitoring and acquisition device 181 is located in the processing area, and the spatial light modulator 183 is located between the reflector 14 and the bipartite mirror 15.

[0015] The optical-liquid-gas coupling module 2 includes: a liquid cavity top cover 21, a window pressure block 22, a laser window 23, a coupling unit 24, a gas-liquid partition 25, and a gas cavity bottom plate 26;

[0016] The liquid chamber top cover 21, coupling unit 24, gas-liquid partition 25 and gas chamber bottom plate 26 are sequentially and sealed from top to bottom;

[0017] The laser window 23 is a light-transmitting sheet, which is sealed and fixed to the lower end of the window pressure block 22; the window pressure block 22 is sealed and connected to the middle of the upper end of the coupling unit 24, and the center of the laser window 23 is through to the top.

[0018] The coupling unit 24 is provided with a water passage structure and an air passage structure at its upper and lower parts, respectively;

[0019] The waterway structure includes a high-pressure inlet 241, an upper annular dispersion cavity I 242, n evenly distributed flat U-shaped turning cavities 243, n vertical transmission cavities 244, a lower horizontal cylindrical cavity I 245, an optical-liquid coupling cavity 252, and a slow-flow boss 251 connected in sequence, where n ≥ 3;

[0020] The slow-flow boss 251 is located between the lower horizontal cylindrical cavity I 245 and the optical-liquid coupling cavity 252;

[0021] The gas path structure includes an air inlet 248, an upper annular dispersion cavity II 249, a vertically distributed transmission cavity 253 at the bottom of the ring, a lower horizontal cylindrical cavity II 261, a focusing and converging cone 262, and an outlet 263 connected in sequence.

[0022] The optical-liquid coupling cavity 252 and the outlet 263 are arranged vertically opposite each other.

[0023] Both the gas-liquid baffle 25 and the gas chamber bottom plate 26 are provided with horizontal adjustment margin and are provided with their own horizontal fine adjustment structures.

[0024] The relative position of the gas-liquid baffle 25 and the coupling unit 24 can be adjusted to adjust the laser focus at the axis of the optical-liquid coupling cavity 252;

[0025] The relative position of the gas chamber bottom plate 26 and the gas-liquid baffle 25 can also be adjusted to adjust the coaxial flow of the liquid jet and the focusing gas.

[0026] The focused laser beam is focused into the optical-liquid coupling cavity 252 through the laser window 23 and initially coupled with the liquid. After being refined by the annular focusing gas, it is emitted from the outlet 263, which is a circular hole with a diameter of 0.1-1 mm.

[0027] The ultrasound auxiliary module 3 includes an ultrasound input connection part 31, an ultrasound amplification unit 32, a fixing frame 33, and an ultrasound output connection plate 34.

[0028] The ultrasonic input connection part 31 is equipped with an ultrasonic generator at the lower part, and ultrasonic amplification units 32 are evenly distributed around its upper side using a fixing frame 33; the upper end of the ultrasonic amplification unit 32 is fixedly connected to the lower end of the workpiece fixing table 42 of the moving module 4 via an ultrasonic output connection plate 34.

[0029] The workpiece 41 is provided on the workpiece fixing table 42;

[0030] The ultrasonic amplification unit 32 includes, from bottom to top, an input block 321, a transmission block 322, a symmetrical first-stage amplification mechanism 323, a symmetrical second-stage amplification mechanism 324, a symmetrical stiffness-enhancing hinge 325, and an output block 326 connected in sequence.

[0031] The moving module 4 includes a workpiece 41, a workpiece fixing table 42, a horizontal moving table 43, a horizontal fixing table 44, a vertical moving table 45, a vertical fixing table 46, and a coupling block connecting plate 47.

[0032] The horizontal fixed platform 44 and the vertical fixed platform 46 are arranged vertically, and the horizontal moving platform 43 and the vertical moving platform 45 are respectively provided on the two platforms;

[0033] The horizontal moving stage 43 can drive the ultrasonic auxiliary module 3 and the workpiece 41 to move horizontally.

[0034] The vertical moving stage 45 can drive the coupling block connecting plate 47 and the photo-liquid-gas coupling module 2 fixed on it to move vertically.

[0035] Another objective of this invention is to provide an ultrasonic-assisted water-conducting laser drilling method based on flow focusing, comprising the following steps:

[0036] Step 1: Fix the workpiece 41 to be drilled onto the workpiece fixing table 42;

[0037] Step 2: Turn on the indicator light source of laser 11, observe and adjust the laser focus to the center position of coupling unit 24 with the help of coupling observation CCD camera 17, and precisely adjust the coupling coaxiality of optical-liquid-gas coupling module 2 by using optical-liquid coaxial adjustment screw 254 and liquid-gas coaxial adjustment screw 265.

[0038] Step 3: First, flowing focusing gas is introduced through the air inlet 248, and then high-pressure purified water of the water guide laser is introduced through the high-pressure water inlet 241 to form a refined water guide beam under the indicator light.

[0039] Step 4: Turn on the ultrasonic generator, and use the ultrasonic auxiliary module 3 to drive the workpiece 41 to generate ultrasonic vibration;

[0040] Step 5: Simultaneously turn on the processing laser beam and monitoring and control group 18, and adjust the laser parameters in real time through closed-loop control to perform drilling processing;

[0041] Step Six: After the drilling process is completed, first turn off the laser source and monitoring and control group 18, then turn off the ultrasonic generator, and stop the supply of high-pressure water and focusing gas.

[0042] The laser 11 is a nanosecond laser with a wavelength of 532nm or 1064nm. The pressure of the high-pressure purified water is 0.5MPa-3MPa, the pressure of the focusing gas is 0.1MPa-2.5MPa, and the frequency of the ultrasonic vibration is 20kHz-30kHz.

[0043] This invention provides a flow-focused, ultrasonic-assisted water-guided laser drilling device and method, belonging to the field of water-guided laser processing technology. The device includes an optical path control module, an optical-liquid-gas coupling module, an ultrasonic assistance module, and a movement module. It employs a laser energy control method that uses in-situ monitoring and real-time adjustment during laser processing. A uniform laminar water jet is obtained through a multi-channel, distributed high-pressure water path design, and the coupling energy beam is controlled using flow-focused water-guided laser beam refinement technology. Ultrasonic vibration-assisted processing further improves the drilling quality. In summary, this invention can be used for the precision machining of hole structures in aerospace components, improving machining quality and thus enhancing the overall service performance of equipment.

[0044] The beneficial effects of this invention are as follows:

[0045] 1. This invention uses a water-guided laser beam to drill holes in aerospace components. The laser energy is adjusted in real time through in-situ monitoring, which reduces the accumulation of processing deviations and improves processing efficiency and yield.

[0046] 2. The water-guided laser beam is refined using flow focusing technology to drill holes in the workpiece with a more stable removal function. The method is simple, low-cost, and produces good processing quality.

[0047] 3. The workpiece is vibrated axially along the laser beam direction by an ultrasonic generator, which directly assists in the ejection of molten material (processing residue);

[0048] 4. This invention adopts a modular design scheme, which is reasonable, compact in structure, and allows each functional module to work together, making it easy to integrate, maintain and replace.

[0049] In summary, this invention can be used for the precision machining of hole structures in aerospace components, improving machining quality and thus enhancing the overall service performance of the equipment. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of the overall structure of the ultrasonic-assisted water-guided laser drilling device based on flow focusing according to the present invention;

[0051] Figure 2 This is a schematic diagram of the overall structure of the optical path adjustment module of the ultrasonic-assisted water-guided laser drilling device based on flow focusing according to the present invention;

[0052] Figure 3 This is an exploded view of the optical-liquid-gas coupling module structure of the ultrasonic-assisted water-guided laser drilling device based on flow focusing according to the present invention;

[0053] Figure 4 This is a schematic diagram of the internal structure of the optical-liquid-gas coupling module of the ultrasonic-assisted water-guided laser drilling device based on flow focusing according to the present invention.

[0054] Figure 5 This is a schematic diagram of the water circuit structure of the optical-liquid-gas coupling module in the ultrasonic-assisted water-guided laser drilling device based on flow focusing of the present invention.

[0055] Figure 6 This is a schematic diagram of the gas path structure of the optical-liquid-gas coupling module in the ultrasonic-assisted water-guided laser drilling device based on flow focusing of the present invention.

[0056] Figure 7 This is a schematic diagram of the optical-liquid coaxial adjustment structure of the optical-liquid-gas coupling module in the ultrasonic-assisted water-guided laser drilling device based on flow focusing of the present invention;

[0057] Figure 8This is a schematic diagram of the liquid-gas coaxial adjustment structure of the optical-liquid-gas coupling module in the ultrasonic-assisted water-guided laser drilling device based on flow focusing of the present invention.

[0058] Figure 9 This is a schematic diagram of the adjustment through-hole structure of the optical-liquid-gas coupling module in the ultrasonic-assisted water-guided laser drilling device based on flow focusing of the present invention.

[0059] Figure 10 This is a three-dimensional structural diagram of the ultrasonic auxiliary module of the ultrasonic-assisted water-guided laser drilling device based on flow focusing according to the present invention;

[0060] Figure 11 This is a three-dimensional structural diagram of the ultrasonic amplification unit of the ultrasonic auxiliary module in the ultrasonic-assisted water-guided laser drilling device based on flow focusing of the present invention.

[0061] Figure 12 This is a three-dimensional structural diagram of the moving module of the ultrasonic-assisted water-guided laser drilling device based on flow focusing according to the present invention.

[0062] In the attached diagram:

[0063] 1. Optical path control module; 11. Laser; 12. Beam expander plano-concave lens; 13. Collimating plano-convex lens; 14. Mirror; 15. Divider lens; 16. Focusing double lens; 17. Coupled observation CCD camera; 18. Monitoring and control group; 181. In-situ monitoring and acquisition device; 182. Industrial control computer; 183. Spatial light modulator;

[0064] 2. Optical-liquid-gas coupling module; 21. Liquid chamber top cover; 22. Window pressure block; 23. Laser window; 24. Coupling unit; 241. High-pressure water inlet; 242. Upper annular dispersion cavity I; 243. 12 evenly distributed flat U-shaped turning cavities; 244. 12 vertical transmission cavities; 245. Lower horizontal cylindrical cavity I; 246. Upper inner and outer sealing rings; 247. Lower liquid-gas sealing ring; 248. Air inlet; 249. Upper annular... 25. Dispersion cavity II; 25. Gas-liquid baffle; 251. Slow-flow boss; 252. Optical-liquid coupling cavity; 253. Annular bottom evenly distributed vertical transmission cavity; 254. Optical-liquid coaxial adjusting screw; 255. Through hole I for connection; 26. Gas cavity bottom plate; 261. Lower horizontal cylindrical cavity II; 262. Focusing and converging cone; 263. Outlet; 264. Gas cavity bottom plate sealing ring; 265. Liquid-gas coaxial adjusting screw; 266. Through hole II for connection;

[0065] 3. Ultrasonic auxiliary module; 31. Ultrasonic input connection part; 32. Ultrasonic amplification unit; 321. Input block; 322. Transmission block; 323. Symmetrical first-stage amplification mechanism; 324. Symmetrical second-stage amplification mechanism; 325. Symmetrical stiffness-enhancing hinge; 326. Output block; 33. Fixing frame; 34. Ultrasonic output connection plate;

[0066] 4. Moving module; 41. Workpiece; 42. Workpiece fixing table; 43. Horizontal moving table; 44. Horizontal fixing table; 45. Vertical moving table; 46. Vertical fixing table; 47. Coupling block connecting plate. Detailed Implementation

[0067] Example 1

[0068] See appendix Figure 1 - Appendix Figure 12 An ultrasonic-assisted water-guided laser drilling device based on flow focusing includes: an optical path control module 1, an optical-liquid-gas coupling module 2, an ultrasonic auxiliary module 3, and a moving module 4.

[0069] The optical path control module 1 is a self-feedback optical path adjustment module, which includes: a laser 11, a beam expander plano-concave lens 12, a collimating plano-convex lens 13, a reflector 14, a bipartite lens 15, a focusing double lens 16, a coupled observation CCD camera 17, and a monitoring and control group 18.

[0070] The laser beam emitted by the laser 11 passes sequentially through a beam-expanding plano-concave lens 12, a collimating plano-convex lens 13, a reflector 14, a bipartite lens 15, and a focusing dual lens 16 before being focused onto the laser window 23 of the optical-liquid-gas coupling module 2.

[0071] The bipartite mirror 15 and the reflector 14 are arranged in parallel to each other on the left and right sides. The upper and lower sides of the bipartite mirror 15 are respectively equipped with a coupling observation CCD camera 17 and a focusing double lens 16.

[0072] The monitoring and control group 18 includes an in-situ monitoring and acquisition unit 181, an industrial control computer 182, and a spatial light modulator 183;

[0073] The in-situ monitoring and acquisition device 181 is located in the processing area, and the spatial light modulator 183 is located between the reflector 14 and the bipartite mirror 15.

[0074] The in-situ monitoring and acquisition device 181 transmits the real-time processing status signal to the industrial control computer 182. The industrial control computer 182 calculates the optimal processing result through an algorithm and feeds it back to the spatial light modulator 183. Then, the spatial light modulator 183 adjusts the laser energy magnitude and cross-sectional energy distribution to optimize the processing parameters.

[0075] The optical-liquid-gas coupling module 2 includes: a liquid cavity top cover 21, a window pressure block 22, a laser window 23, a coupling unit 24, a gas-liquid partition 25, and a gas cavity bottom plate 26;

[0076] The liquid chamber top cover 21, coupling unit 24, gas-liquid baffle 25 and gas chamber bottom plate 26 are arranged sequentially from top to bottom and fixedly connected by screws, and the connection points are all sealed.

[0077] The laser window 23 is a transparent sapphire disc, which is sealed and fixed in the groove at the lower end of the window pressure block 22; the window pressure block 22 is threaded and sealed to the middle of the upper end of the coupling unit 24; the center of the window pressure block 22 is a through structure, and a through hole is also opened at the corresponding position of the liquid cavity top cover 21 on its upper side to ensure that the laser beam can reach the laser window 23.

[0078] The coupling unit 24 is provided with a water passage structure and an air passage structure at its upper and lower parts, respectively;

[0079] The waterway structure includes a high-pressure inlet 241, an upper annular dispersion chamber I 242, 12 evenly distributed flat U-shaped turning chambers 243, 12 vertical transmission chambers 244, a lower horizontal cylindrical chamber I 245, a light-liquid coupling chamber 252, a slow-flow boss 251, upper inner and outer sealing rings 246, and a lower liquid-gas sealing ring 247, all connected in sequence.

[0080] The slow-flow boss 251 is located between the lower horizontal cylindrical cavity I 245 and the optical-liquid coupling cavity 252;

[0081] The upper inner and outer sealing rings 246 are located between the upper end face of the coupling unit 24 and the lower end face of the liquid chamber top cover 21;

[0082] The lower liquid-gas sealing ring 247 is located between the lower end face of the coupling unit 24 and the upper end face of the gas-liquid partition 25.

[0083] The gas path structure includes an air inlet 248, an upper annular dispersion cavity II 249, a vertically distributed transmission cavity 253 at the bottom of the ring, a lower horizontal cylindrical cavity II 261, a focusing and converging cone 262, an outlet 263, and a sealing ring 264 for the bottom plate of the gas cavity, which are connected in sequence.

[0084] The gas chamber bottom plate sealing ring 264 is located between the upper end face of the gas chamber bottom plate 26 and the lower end face of the gas-liquid partition 25;

[0085] The optical-liquid coupling cavity 252 and the outlet 263 are arranged vertically opposite to each other.

[0086] The optical-liquid-gas coupling module 2 also includes optical-liquid coaxial adjusting screws 254 and liquid-gas coaxial adjusting screws 265 arranged in an upper and lower cross-shaped circumference.

[0087] The optical-liquid coaxial adjusting screw 254 can adjust the relative position of the gas-liquid partition 25 and the coupling unit 24, thereby adjusting the laser focus at the axis of the optical-liquid coupling cavity 252.

[0088] The liquid-gas coaxial adjusting screw 265 can adjust the relative position of the gas chamber bottom plate 26 and the gas-liquid partition 25, thereby adjusting the liquid stream and the focusing gas to flow out coaxially, and avoiding uneven gas driving force on the liquid stream.

[0089] The gas-liquid partition 25 is provided with a horizontal adjustment margin connection through hole I 255, and the gas chamber bottom plate 26 is also provided with a horizontal adjustment margin connection through hole II 266.

[0090] The focused laser beam is focused into the optical-liquid coupling cavity 252 through the laser window 23, where it is initially coupled with the fluid. After being refined by the annular focusing gas, it is emitted from the outlet 263.

[0091] The outlet 263 is a circular hole with a diameter of 0.1-1 mm.

[0092] The ultrasonic auxiliary module 3 is located between the workpiece fixing stage 42 and the horizontal moving stage 43 of the moving module 4;

[0093] The ultrasound auxiliary module 3 includes an ultrasound input connection part 31, an ultrasound amplification unit 32, a fixing frame 33, and an ultrasound output connection plate 34.

[0094] The ultrasonic input connection part 31 is equipped with an ultrasonic generator at the lower part, and ultrasonic amplification units 32 with flexible hinge mechanisms are evenly distributed around the upper side of the fixed frame 33; the upper end of the ultrasonic amplification unit 32 is fixedly connected to the lower end of the workpiece fixed table 42 via the ultrasonic output connection plate 34.

[0095] The ultrasonic amplification unit 32 includes, from bottom to top, an input block 321, a transmission block 322, a symmetrical first-stage amplification mechanism 323, a symmetrical second-stage amplification mechanism 324, a symmetrical stiffness-enhancing hinge 325, and an output block 326 connected in sequence.

[0096] The moving module 4 includes: a workpiece 41, a workpiece fixing table 42, a horizontal moving table 43, a horizontal fixing table 44, a vertical moving table 45, a vertical fixing table 46, and a coupling block connecting plate 47.

[0097] The horizontal fixed platform 44 and the vertical fixed platform 46 are vertically arranged, and the horizontal moving platform 43 and the vertical moving platform 45 are respectively located on the two platforms; the horizontal moving platform 43 can drive the ultrasonic auxiliary module 3 and the workpiece 41 to move horizontally.

[0098] The photo-liquid-gas coupling module 2 is mounted on the coupling block connecting plate 47 of the moving module 4;

[0099] The vertical moving stage 45 can drive the coupling block connecting plate 47 and its optical-liquid-gas coupling module 2 to move vertically.

[0100] This invention also provides an ultrasonic-assisted water-conducting laser drilling method based on flow focusing, comprising the following steps:

[0101] Step 1: Fix the workpiece 41 to be drilled onto the workpiece fixing table 42;

[0102] Step 2: Turn on the indicator light source of laser 11, observe and adjust the laser focus to the center position of coupling unit 24 with the help of coupling observation CCD camera 17, and precisely adjust the coupling coaxiality of optical-liquid-gas coupling module 2 by using optical-liquid coaxial adjustment screw 254 and liquid-gas coaxial adjustment screw 265.

[0103] Step 3: First, the gas required for flow focusing is introduced through the air inlet 248. Then, high-pressure purified water for water-guided laser is introduced through the high-pressure water inlet 241 to form a refined water-guided beam under the indicator light.

[0104] Step 4: Turn on the ultrasonic generator, and use the ultrasonic auxiliary module 3 to drive the workpiece 41 to generate ultrasonic vibration;

[0105] Step 5: Simultaneously turn on the processing laser beam and monitoring and control group 18, and adjust the laser parameters in real time through closed-loop control to perform drilling processing;

[0106] Step Six: After the drilling process is completed, first turn off the laser source and monitoring and control group 18, then turn off the ultrasonic generator, and stop the supply of high-pressure water and focusing gas.

[0107] The laser 11 is a nanosecond laser with a wavelength of 532nm or 1064nm. The pressure of the high-pressure purified water is 0.5MPa-3MPa, the pressure of the focusing gas is 0.1MPa-2.5MPa, and the ultrasonic vibration frequency is 20kHz-30kHz.

Claims

1. An ultrasonic assisted water-jet laser drilling apparatus based on flow focusing, characterized in that, include: Laser (11), optical path control module (1), optical-liquid-gas coupling module (2), ultrasonic auxiliary module (3), and moving module (4); The optical-liquid-gas coupling module (2) includes: a liquid cavity top cover (21), a window pressure block (22), a laser window (23), a coupling unit (24), a gas-liquid partition (25), and a gas cavity bottom plate (26). The liquid chamber top cover (21), coupling unit (24), gas-liquid partition (25) and gas chamber bottom plate (26) are sequentially and sealed from top to bottom; The laser window (23) is a light-transmitting sheet, which is sealed and fixed to the lower end of the window pressure block (22); the window pressure block (22) is sealed and connected to the middle of the upper end of the coupling unit (24), and the center of the laser window (23) is through to the top. The coupling unit (24) is provided with a water passage structure and an air passage structure at the top and bottom, respectively; The waterway structure includes a high-pressure inlet (241), an upper annular dispersion cavity I (242), n evenly distributed flat U-shaped turning cavities (243), n vertical transmission cavities (244), a lower horizontal cylindrical cavity I (245), an optical-liquid coupling cavity (252), and a slow-flow boss (251) connected in sequence, where n≥3; The slow-flow boss (251) is located between the lower horizontal cylindrical cavity I (245) and the optical-liquid coupling cavity (252); The gas path structure includes an air inlet (248), an upper annular dispersion cavity II (249), a vertically distributed transmission cavity (253) at the bottom of the ring, a lower horizontal cylindrical cavity II (261), a focusing and converging cone (262), and an outlet (263) connected in sequence. The optical-liquid coupling cavity (252) and the outlet (263) are arranged vertically opposite each other; The ultrasound auxiliary module (3) includes an ultrasound input connection part (31), an ultrasound amplification unit (32), a fixing frame (33), and an ultrasound output connection plate (34). The ultrasonic input connection part (31) is equipped with an ultrasonic generator at the bottom, and ultrasonic amplification units (32) are evenly distributed around the upper side of the fixed frame (33); the upper end of the ultrasonic amplification unit (32) is fixed to the lower end of the workpiece fixing table (42) of the moving module (4) via the ultrasonic output connection plate (34); the workpiece (41) is mounted on the workpiece fixing table (42). The ultrasonic amplification unit (32) includes an input block (321), a transmission block (322), a symmetrical first-stage amplification mechanism (323), a symmetrical second-stage amplification mechanism (324), a symmetrical stiffness-enhancing hinge (325), and an output block (326) connected sequentially from bottom to top.

2. The flow-focussing based ultrasonic assisted water guided laser drilling apparatus as claimed in claim 1, wherein: The gas-liquid baffle (25) and the gas chamber bottom plate (26) are both provided with horizontal adjustment margin and are provided with their own horizontal fine adjustment structure; The relative position of the gas-liquid baffle (25) and the coupling unit (24) can be adjusted to adjust the laser focus at the axis of the optical-liquid coupling cavity (252); The relative positions of the gas chamber bottom plate (26) and the gas-liquid baffle (25) can also be adjusted to adjust the coaxial flow of the liquid jet and the focusing gas. The focused laser beam is focused through the laser window (23) into the optical-liquid coupling cavity (252) and initially coupled with the liquid. After being refined by the annular focusing gas, it is emitted from the outlet (263), which is a circular hole with a diameter of 0.1-1 mm.

3. The ultrasonic-assisted water-guided laser drilling device based on flow focusing according to claim 2, characterized in that: The optical path control module (1) includes: a lens group, a reflector (14), a bipartite mirror (15), a focusing double lens (16), a coupled observation CCD camera (17), and a monitoring and control group (18). The laser beam emitted by the laser (11) is focused onto the laser window (23) of the optical-liquid-gas coupling module (2) by the lens group, the reflector (14), the bipartite lens (15), and the focusing double lens (16) in sequence.

4. The ultrasonic-assisted water-conducting laser drilling device based on flow focusing according to claim 3, characterized in that: The bipartite mirror (15) and the reflector (14) are arranged in parallel. The upper and lower sides of the bipartite mirror (15) are respectively equipped with a coupled observation CCD camera (17) and a focusing double lens (16).

5. The ultrasonic-assisted water-conducting laser drilling device based on flow focusing according to claim 4, characterized in that: The monitoring and control group (18) includes an in-situ monitoring and acquisition unit (181), an industrial control computer (182), and a spatial light modulator (183). The in-situ monitoring and acquisition device (181) is located in the processing area, and the spatial light modulator (183) is located between the reflector (14) and the bipartite mirror (15).

6. The flow-focussing based ultrasonic assisted water guided laser drilling apparatus as claimed in claim 5, wherein: The moving module (4) includes a workpiece (41), a workpiece fixing table (42), a horizontal moving table (43), a horizontal fixing table (44), a vertical moving table (45), a vertical fixing table (46), and a coupling block connecting plate (47). The horizontal fixed platform (44) and the vertical fixed platform (46) are set vertically, and the horizontal moving platform (43) and the vertical moving platform (45) are respectively provided on the two platforms. The horizontal moving stage (43) can drive the ultrasonic auxiliary module (3) and the workpiece (41) to move horizontally; The vertical moving stage (45) can drive the coupling block connecting plate (47) and the optical-liquid-gas coupling module (2) fixed on it to move vertically.

7. The flow-focussing based ultrasonic assisted water guided laser drilling apparatus as claimed in claim 6, wherein: The laser (11) is a nanosecond laser with a wavelength of 532nm or 1064nm. The pressure of the purified water introduced into the water channel structure is 0.5MPa-3MPa, the pressure of the focusing gas is 0.1MPa-2.5MPa, and the ultrasonic auxiliary frequency is 20kHz-30kHz.

8. A flow-focused ultrasonic-assisted water-conducting laser drilling method, characterized in that: The ultrasonic-assisted water-conducting laser drilling device based on flow focusing as described in claim 4 includes the following steps: Step 1: Fix the workpiece (41) to be drilled onto the workpiece fixing table (42). Step 2: Turn on the indicator light source of the laser (11), observe and adjust the laser focus to the center position of the coupling unit (24) with the help of the coupling observation CCD camera (17), and precisely adjust the coupling coaxiality of the optical-liquid-gas coupling module (2) by using the optical-liquid coaxial adjustment screw (254) and the liquid-gas coaxial adjustment screw (265). Step 3: First, flowing focusing gas is introduced through the air inlet (248), and then high-pressure purified water of the water guide laser is introduced through the high-pressure water inlet (241) to form a refined water guide beam under the indicator light. Step 4: Turn on the ultrasonic generator and drive the workpiece (41) to generate ultrasonic vibration through the ultrasonic auxiliary module (3); Step 5: Simultaneously turn on the processing laser beam and the monitoring and control group (18), and adjust the laser parameters in real time through closed-loop control to perform drilling processing; Step 6: After the drilling process is completed, first turn off the laser source and monitoring and control group (18), then turn off the ultrasonic generator and stop the supply of high-pressure water and focusing gas.

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