Water guide laser coupling device

Abstract

The application belongs to the technical field of laser processing application, and discloses a water guide laser coupling device, which comprises a base, an optical window module and a nozzle assembly arranged in the installation cavity in the base, and an air channel protection module arranged on the base, a coupling cavity is formed between the optical window module and the nozzle assembly, and the axial height of the coupling cavity is adjustable; the air channel protection module is located at the output end of the nozzle assembly, and the air channel protection module comprises an elastic air channel pipe which is coaxially arranged with the nozzle assembly and has an adjustable aperture. The axial height of the coupling cavity can be adjusted in real time according to laser power fluctuation, and the thickness of the high-pressure water layer can be dynamically changed, so that the coupling efficiency is improved; the aperture of the elastic air channel pipe can be adjusted, a tight physical barrier is constructed around the light beam to intercept residues, the problem that the water beam is easy to lose stability and break in the machining of a micro-hole with a large depth-diameter ratio is solved, and reliable equipment support is provided for realizing efficient and consistent industrial precision manufacturing.

Description

Technical Field

[0001] This invention relates to the field of laser processing application technology, and in particular to a water-guided laser coupling device. Background Technology

[0002] Water-guided laser processing technology utilizes a water beam to guide a laser beam to the workpiece surface for processing, offering unique advantages in both efficient cooling and precision machining. Existing water-guided laser processing devices generally employ a fixed gap design between the glass window and the ruby ​​nozzle, meaning the coupling cavity structure cannot be adjusted once it's finalized. Under continuous high-power laser action, a fixed-thickness water layer cannot dynamically adapt to the actual power density. As laser energy increases, an excessively thin water layer struggles to absorb and dissipate the rapidly accumulating heat, leading to significant heat conduction to the optical window, causing localized overheating or even burn-out, thus affecting the lifespan and safety of the optical system. Furthermore, the optimal coupling efficiency between the laser and the water beam is extremely sensitive to the water layer thickness; different power levels correspond to different optimal coupling cavities. Fixed-gap structures can only be designed as a compromise for specific power levels, failing to maintain ideal beam transmission conditions under high-power conditions, resulting in increased coupling energy loss and reduced processing efficiency.

[0003] To meet the high-power processing requirements of aerospace and other fields for micro-holes with large aspect ratios (aspect ratio > 20:1, aperture < 1mm), existing water-guided laser processing devices suffer from low processing efficiency and insufficient service life and safety. Moreover, as the processing depth of micro-holes increases, violent backsplashing occurs during material removal within the narrow space of the micro-holes with large aspect ratios. When a large amount of residue and water splash back, the air duct cannot effectively block contaminants from entering, causing contaminants to enter the air duct and interfere with the airflow field. This can easily disrupt the total reflection interface conditions of the water beam, or even directly cause the water beam to break, severely restricting the processing quality of micro-holes with large aspect ratios. Summary of the Invention

[0004] The purpose of this invention is to provide a water-guided laser coupling device to solve the problems of low efficiency and insufficient processing quality in the process of machining micro-holes with large aspect ratios, and to improve the manufacturing level of precision parts in aerospace and other fields.

[0005] To achieve this objective, the present invention adopts the following technical solution: A water-guided laser coupling device, comprising: The base has an internal mounting cavity; An optical window module, wherein the optical window module is disposed within the mounting cavity; A nozzle assembly is disposed within the mounting cavity and spaced apart from the optical window module. A coupling cavity is formed between the optical window module and the nozzle assembly, and the axial height of the coupling cavity is adjustable. An airway protection module is installed on the base and located at the output end of the nozzle assembly. The airway protection module includes a flexible airway tube, which is coaxially arranged with the nozzle assembly, and the orifice diameter of the flexible airway tube is adjustable.

[0006] In some embodiments, the water-guided laser coupling device further includes a coupling gap adjustment device disposed on the base and connected to the nozzle assembly. The coupling gap adjustment device is configured to drive the nozzle assembly to move along the axial direction of the mounting cavity to adjust the axial height of the coupling cavity.

[0007] In some embodiments, the base includes an inner base slidably disposed within the mounting cavity, the nozzle assembly is disposed on the inner base, and the coupling gap adjustment device is connected to the inner base to drive the inner base to move the nozzle assembly axially.

[0008] In some embodiments, the coupling gap adjustment device includes: A driving component, which is disposed on the base and located on the outside of the base; A transmission assembly is disposed at the output end of the drive component, and the transmission assembly is disposed through the base from the outside to the inside. A movable slider is fixedly connected to the inner base. The movable slider is located at the end of the transmission assembly opposite to the driving member. The driving member drives the movable slider to move axially through the transmission assembly.

[0009] In some embodiments, the transmission assembly includes a ball screw pair, which includes a screw shaft and a nut seat. The nut seat is fixedly mounted on the movable slider. One end of the screw shaft is connected to the output end of the drive member, and the other end of the screw shaft is engaged with the nut seat. When the drive member drives the screw shaft to rotate, the nut seat drives the movable slider to move axially.

[0010] In some embodiments, a linear guide rail is provided between the circumference of the inner base and the sidewall of the mounting cavity.

[0011] In some embodiments, the inner base has a stepped surface on its side facing the output end of the nozzle assembly. When the inner base moves toward the optical window module to the coupling cavity with a minimum axial height, the stepped surface abuts against the inner wall of the mounting cavity.

[0012] In some embodiments, an elastic element is provided between the end face of the inner base facing the output end of the nozzle assembly and the inner wall of the mounting cavity.

[0013] In some embodiments, the airway protection module further includes a plurality of compression components, which are evenly spaced around the circumferentially spaced elastic airway tube. The output end of each compression component can move toward or away from the elastic airway tube. When the output end of the compression component moves toward the elastic airway tube, it can compress the elastic airway tube, causing the orifice of the elastic airway tube to shrink.

[0014] In some embodiments, the extrusion assembly includes: A drive mechanism, the output end of which is arranged along the radial direction of the elastic airway tube; A transmission mechanism, one end of which is connected to the output end of the drive mechanism; A compression block is disposed at one end of the transmission mechanism away from the drive mechanism. The drive mechanism can drive the compression block to move toward the elastic airway tube through the transmission mechanism to compress the elastic airway tube.

[0015] In some embodiments, the airway protection module further includes a pressure auxiliary regulating device, which includes a housing, one end of which is fixed to the base and the other end is sealed to form a pressurization chamber; the housing is fitted with the elastic airway tube and the compression assembly, and the side wall of the housing is provided with an air inlet for injecting auxiliary pressurizing gas into the pressurization chamber; the drive mechanism is fixed to the housing.

[0016] In some embodiments, the water-guided laser coupling device further includes a control unit, which is communicatively connected to the coupling gap adjustment device and the airway protection module to control the axial height of the coupling cavity and the aperture of the elastic airway tube.

[0017] In some embodiments, the water-guided laser coupling device further includes a monitoring component, the monitoring component comprising: A first displacement sensor is mounted on the movable slider; A second displacement sensor is mounted on the extrusion block; A backwater splash monitoring sensor is installed on the housing at one end away from the base; The first displacement sensor, the second displacement sensor, and the backwater splash monitoring sensor are all communicatively connected to the control unit.

[0018] In some embodiments, the control unit controls the axial height of the coupling cavity, specifically by: The control unit monitors the laser energy in real time, and when the laser power P is detected... t Exceeding the preset laser threshold P th When this happens, the compensation equation of the coupling cavity is preset. The current axial height H of the coupling cavity is calculated in real time. t The target axial height H of the coupling cavity is reached th The difference between ; in, This is the heat flow compensation coefficient. For transient response factor, This represents the change in laser power. The control unit will calculate the difference. The pulse command is converted into a pulse and sent to the coupling gap adjustment device to adjust the axial height of the coupling cavity.

[0019] In some embodiments, the control unit controls the aperture of the flexible airway tube, specifically: The control unit receives the voltage signal V from the backwater splash monitoring sensor. t The voltage signal V t Converted to real-time backwash spray volume M t According to the real-time backflow spray volume M t Determine the target aperture D of the elastic airway tube. t ; When the real-time backflow splash volume M is detected t Exceeding the set threshold M th At that time, the control unit calculates the real-time backwater splash volume M. t Calculate the target stroke X of the extrusion block: in, The depth-to-diameter ratio protection factor, D is the transmission efficiency coefficient of the transmission mechanism. max The maximum initial aperture for the elastic airway tube in its naturally relaxed state; The control unit sends the target stroke to the extrusion assembly.

[0020] The beneficial effects of this invention are: The water-guided laser coupling device provided by this invention features an adjustable axial height of the coupling cavity, allowing for real-time adjustment of the cavity based on laser power fluctuations. This dynamically changes the thickness of the high-pressure water layer. When the laser power increases, the axial height of the coupling cavity is adjusted to compensate for the increase, ensuring the water layer thickness approaches the target value corresponding to the current laser power condition. The height-adjustable coupling cavity enhances water flow heat dissipation and reduces the thermal load on the optical window module. Furthermore, it brings the laser-water beam coupling state closer to the optimal matching state under that condition, thereby improving coupling efficiency. This adaptive adjustment mechanism helps suppress the thermal lensing effect under prolonged high-power laser operation, extends the lifespan of the optical window and core components, and improves the stability of high-power continuous processing equipment.

[0021] The water-guided laser coupling device provided by this invention, by setting an airway protection module, includes an elastic airway tube, which is coaxially arranged with the nozzle assembly. The aperture of the elastic airway tube is adjustable, thereby enabling flexible control of the aperture of the elastic airway tube. It can build a tight physical barrier around the beam to intercept residues, improve the problem of water beam instability and breakage in the processing of micro-holes with large aspect ratios using water-guided lasers, and provide reliable equipment support for achieving high-efficiency and high-consistency industrial precision manufacturing. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the external structure of the water-guided laser coupling device provided in an embodiment of the present invention; Figure 2 This is a cross-sectional view of the water-guided laser coupling device provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the coupling gap adjustment device in the water-guided laser coupling device provided in this embodiment of the invention; Figure 4 This is a schematic diagram of the airway protection module in the water-guided laser coupling device provided in this embodiment of the invention from a bottom-view angle. Figure 5 This is a schematic diagram of the airway protection module in the water-guided laser coupling device provided in this embodiment of the invention; Figure 6 This is a schematic diagram of the control principle of the control unit in the water-guided laser coupling device provided in an embodiment of the present invention; Figure 7 This is a flowchart of the process of machining microholes with a large aspect ratio using the water-guided laser coupling device provided in the embodiments of the present invention; Figure 8 This is a schematic diagram of the damage state of the optical window module during the machining of micro-holes with a large aspect ratio using a water-guided laser coupling device in the existing technology. Figure 9This is a schematic diagram showing the intact state of the optical window module when using the water-guided laser coupling device provided in the embodiments of the present invention to process micro-holes with a large aspect ratio.

[0023] In the picture: 100. Base; 101. Top seat; 1011. Water inlet channel; 1012. Protective gas channel; 102. Lower base; 103. Inner base; 1031. Stepped surface; 104. Linear guide rail; 105. Elastic element; 200. Optical window module; 300. Coupling cavity; 400. Nozzle assembly; 401. Nozzle; 402. Sleeve; 403. Flow guide seat; 500. Coupling gap adjustment device; 501. Driving component; 502. Transmission assembly; 503. Moving slider; 504. First displacement sensor; 600. Airway protection module; 601. Elastic airway tube; 602. Drive mechanism; 603. Transmission mechanism; 604. Compression block; 605. Housing; 6051. Air inlet; 606. Fixing plate; 607. Pressurization chamber; 608. Second displacement sensor; 609. Backwater splash monitoring sensor. Detailed Implementation

[0024] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0025] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0026] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0027] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0028] This invention provides a water-guided laser coupling device suitable for machining micro-holes with large aspect ratios, such as... Figures 1-5 As shown, the water-guided laser coupling device includes a base 100, an optical window module 200, a nozzle assembly 400, and an airway protection module 600. The base 100 has an internal mounting cavity; the optical window module 200 is disposed within the mounting cavity; the nozzle assembly 400 is disposed within the mounting cavity and spaced apart from the optical window module 200, forming a coupling cavity 300 between the optical window module 200 and the nozzle assembly 400. The axial height of the coupling cavity 300 is adjustable. The airway protection module 600 is mounted on the base 100 and located at the output end of the nozzle assembly 400. The airway protection module 600 includes an elastic airway tube 601, which is coaxially arranged with the nozzle assembly 400, and the aperture of the elastic airway tube 601 is adjustable.

[0029] The water-guided laser coupling device provided by this invention, such as Figure 1 and Figure 2As shown, the base 100 includes an upper top seat 101 and a lower base 102. The upper top seat 101 and the lower base 102 are sealed together to form an installation cavity. The side wall of the upper top seat 101 is provided with a water inlet channel 1011 and a protective gas channel 1012. The coupling cavity 300 is connected to the water inlet channel 1011 and forms a coupling cavity 300 between the bottom surface of the optical window module 200 and the plane where the nozzle assembly 400 is located. High-pressure water flow is introduced symmetrically and tangentially through the water inlet channel 1011 to form a stable water layer in the coupling cavity 300 for beam transmission and local heat absorption. By making the axial height of the coupling cavity 300 adjustable, the water layer thickness can be adjusted. This allows for real-time adjustment of the coupling cavity 300 based on the relationship between laser power and water layer thickness, dynamically changing the high-pressure water layer thickness according to laser power fluctuations. When the laser power increases, the axial height of the coupling cavity 300 is adjusted to compensate for this, ensuring the water layer thickness approaches the target value corresponding to the current laser power condition. The adjustable axial height of the coupling cavity 300 enhances water flow heat dissipation and reduces the thermal load on the optical window module 200. Furthermore, it brings the laser-water beam coupling state closer to the optimal matching state under this condition, thereby improving coupling efficiency. This adaptive adjustment mechanism helps suppress the thermal lensing effect under long-term high-power laser operation, extends the lifespan of the core components of the optical window module 200, and improves the stability of high-power continuous processing in the water-guided laser coupling device.

[0030] The water-guided laser coupling device provided by the present invention, by setting the aperture of the elastic air duct 601 to be adjustable, and by flexibly adjusting the aperture of the elastic air duct 601, can build a tight physical barrier around the beam to intercept residues, improve the problem of water beam instability and breakage in the processing of micro-holes with large aspect ratios, and provide reliable equipment support for achieving high-efficiency and high-consistency industrial precision manufacturing.

[0031] In some embodiments, the water-guided laser coupling device further includes a coupling gap adjustment device 500, which is disposed on the base 100 and connected to the nozzle assembly 400. The coupling gap adjustment device 500 is configured to drive the nozzle assembly 400 to move along the axial direction of the mounting cavity to adjust the axial height of the coupling cavity 300.

[0032] like Figure 1 and Figure 2 As shown, it can be understood that in the axial height adjustment scheme of the coupling cavity 300, the optical window module 200 can be fixed and the nozzle assembly 400 can be movable, or the nozzle assembly 400 can be fixed and the optical window module 200 can be movable. This embodiment of the invention uses a coupling gap adjustment device 500 to control the axial movement of the nozzle assembly 400, thereby adjusting the axial height of the coupling cavity 300, facilitating control and connection.

[0033] In some embodiments, the base 100 includes an inner base 103, which is slidably disposed in the mounting cavity. The nozzle assembly 400 is disposed on the inner base 103. The coupling gap adjustment device 500 is connected to the inner base 103 to drive the inner base 103 to move the nozzle assembly 400 axially.

[0034] like Figure 1 and Figure 2 As shown, the base 100 adopts a high-rigidity three-stage split structure. The upper base 101 has a rectangular notch channel, and the interior of the rectangular notch channel is provided with a first chamber. The first chamber is used for high-precision positioning and to accommodate the optical window module 200 and the inner base 103. The inner base 103 has a second chamber, which is used to install and set the nozzle assembly 400. A coupling cavity 300 is formed between the upper base 101 and the inner base 103. The lower base 102 has a third chamber, which is used to accommodate and connect the airway protection module 600. The first chamber, the second chamber and the third chamber are coaxially connected along the laser optical axis, and together they form a pressure space for laser coupling with high-pressure water flow. The first chamber and the third chamber constitute the mounting cavity. This split base 100 can ensure that the water-guided laser coupling device can withstand the environment of 10-30MPa high-pressure water impact, which helps to control the dynamic coaxiality error between the inner base 103 and the base 100 within 2μm, and helps to reduce the water beam eccentricity and optical path offset caused by adjusting the axial height of the coupling cavity 300.

[0035] The inner base 103 is disposed within the mounting cavity between the upper top seat 101 and the lower base 102. The inner base 103, nozzle assembly 400, and optical window module 200 are all coaxially arranged with the base 100. By providing a movable inner base 103, the nozzle assembly 400 can be mounted on the inner base 103, facilitating control of the movement of the nozzle assembly 400 via the inner base 103, and simplifying connection and drive control. In this embodiment, as... Figure 2 The nozzle assembly 400 is precision assembled from three parts: a nozzle 401, a sleeve 402, and a flow guide seat 403. The nozzle 401 is made of ruby, and its inlet is designed as a smooth, rounded conical transition surface with a radius of 0.5-1.0 mm. The sleeve 402 is made of stainless steel and has a hollow cylindrical structure with a central mounting hole. The sleeve 402 is fixed to the interface of the flow guide seat 403 by flange clamping. To ensure high-pressure water sealing, a sealing element is also provided between the contact surfaces of the sleeve 402 and the flow guide seat 403.

[0036] In some embodiments, the coupling gap adjustment device 500 in the water-guided laser coupling device includes a driving member 501, a transmission assembly 502, and a movable slider 503. The driving member 501 is disposed on the base 100 and located on the outside of the base 100. The transmission assembly 502 is disposed at the output end of the driving member 501 and passes through the base 100 from the outside to the inside. The movable slider 503 is fixedly connected to the inner base 103 and is disposed at the end of the transmission assembly 502 away from the driving member 501. The driving member 501 drives the movable slider 503 to move axially through the transmission assembly 502.

[0037] The movable slider 503 is rigidly connected to the inner base 103 (e.g., by welding). The drive component 501 can be configured as a rotary or linear output component, such as a micro servo motor, to achieve precise displacement control of the movable slider 503 and the inner base 103. The movement of the movable slider 503 is driven by a transmission assembly 502. The transmission assembly 502 facilitates the fixed installation and automatic control of the drive component 501, and also ensures a sealed installation between the transmission assembly 502 and the base 100.

[0038] Combination Figure 2 and Figure 3 As shown, the transmission assembly 502 employs a precision ball screw pair, which includes a screw shaft and a nut seat. The nut seat is fixedly mounted on the movable slider 503. One end of the screw shaft is connected to the output end of the drive component 501, and the other end is threadedly connected to the nut seat. The drive component 501 is connected to the screw shaft via a coupling. The screw shaft is parallel to the laser optical axis. The threaded connection between the screw shaft and the nut seat converts the rotational output of the drive component 501 into the axial movement of the movable slider 503, thereby achieving micron-level linear displacement of the inner base 103 and the nozzle assembly 400 along the laser optical axis. It can be understood that the screw shaft and nut seat combination in the transmission assembly 502 facilitate a sealed installation of the screw shaft through the base 100 from the outside in, and provides more precise displacement control. When the drive component 501 drives the screw shaft to rotate, the rotation of the screw shaft is converted into the movement of the nut seat and the movable slider 503 through the interaction of the screw shaft and the nut seat, thereby driving the axial movement of the inner base 103.

[0039] In some embodiments, a linear guide rail 104 is provided between the inner base 103 and the sidewall of the mounting cavity in the circumferential direction. Preferably, as shown in the figure... Figure 2Multiple linear guides 104 are provided, and the multiple linear guides 104 are evenly spaced around the circumference of the inner base 103. The linear guides 104 are nested in the inner wall of the mounting cavity or the outer wall of the inner base 103. The inner base 103 is constrained by the linear guides 104, ensuring that when the inner base 103 moves the nozzle assembly 400, the nozzle assembly 400 always maintains a high degree of coaxiality along the laser optical axis, thereby achieving precise adjustment of the water layer thickness. In some embodiments, the inner base 103 has a stepped surface 1031 on the side facing the output end of the nozzle assembly 400. When the inner base 103 moves toward the optical window module 200 and has a minimum axial height in the coupling cavity 300, the stepped surface 1031 abuts against the inner wall of the mounting cavity.

[0040] like Figure 2 The side wall of the upper base 101 is provided with a water inlet channel 1011 and a protective gas channel 1012 from top to bottom. The water inlet channel 1011 connects to the top of the inner base 103. The high-pressure water supply unit provides a stable water source to the coupling cavity 300 through the water inlet channel 1011. The protective gas channel 1012 connects to the bottom of the inner base 103. The coupling energy beam protective gas supply unit provides protective gas to the laser beam through the protective gas channel 1012. The inner base 103 is used to isolate and seal the water layer and the protective gas. The rail 104 is located on the side wall of the inner base 103 between the water inlet channel 1011 and the protective gas channel 1012. A stepped surface 1031 is provided on the circumferential side of the inner base 103 facing the output end of the nozzle assembly 400. This step limits the upward movement of the inner base 103, preventing the nozzle assembly 400 from completely disengaging from the optical window module 200, which could lead to the disappearance or excessively small water layer. This helps protect the optical window module 200 and the nozzle assembly 400, ensuring the water layer thickness remains within a safe range. It is understood that the inner wall of the mounting cavity is provided with a stop structure that mates with the stepped surface 1031.

[0041] In some embodiments, an elastic element 105 is provided between the end face of the inner base 103 facing the output end of the nozzle assembly 400 and the inner sidewall of the mounting cavity. For example... Figure 2 The elastic element 105 is a spring and is located below the inner base 103. In this embodiment, two elastic elements 105 are provided. The two elastic elements 105 are evenly spaced below the inner base 103. The elastic elements 105 are used to elastically support the inner base 103, provide elastic buffer for the inner base 103, and keep the inner base 103 in a balanced position after the drive element 501 contacts the drive control, so that the coupling cavity 300 above the inner base 103 has a predetermined water layer thickness.

[0042] In some embodiments, the airway protection module 600 further includes a plurality of compression components, which are evenly spaced around the elastic airway tube 601 in the circumferential direction. The output end of the compression component can move toward or away from the elastic airway tube 601. When the output end of the compression component moves toward the elastic airway tube 601, it can compress the elastic airway tube 601, causing the aperture of the elastic airway tube 601 to shrink.

[0043] like Figure 1 and Figure 2 As shown, the elastic air passage 601 is coaxially mounted below the output end of the nozzle assembly 400, employing a mechanical-pneumatic hybrid drive architecture. The elastic air passage 601 is made of corrosion-resistant elastic polymer material and is sealed to the lower base 102. The interior of the elastic air passage 601 forms a channel for the water supply jet, protective gas, and coupled light beam. When subjected to radial extrusion force and external air pressure, the elastic air passage 601 undergoes elastic deformation and exhibits shape self-recovery characteristics after the force is removed. By incorporating extrusion components, the elastic air passage 601 can be actively extruded to shrink its orifice when needed. Taking three extrusion components as an example, the three pressurizing components apply uniform circumferential pressure to the elastic air passage 601, causing it to shrink uniformly while maintaining a stable internal flow field.

[0044] Taking three circumferentially arranged extrusion components as an example, the three extrusion components have the same structure. Taking one of them as an example, the extrusion component includes a drive mechanism 602, a transmission mechanism 603, and an extrusion block 604. The three drive mechanisms 602 are evenly distributed around the outer periphery of the elastic air passage 601, and the output end of the drive mechanism 602 is arranged along the radial direction of the elastic air passage 601. One end of the transmission mechanism 603 is connected to the output end of the drive mechanism 602. The extrusion block 604 is located at the end of the transmission mechanism 603 away from the drive mechanism 602. The drive mechanism 602 can drive the extrusion block 604 to move toward the elastic air passage 601 to compress the elastic air passage 601 through the transmission mechanism 603, and conversely, release the compression of the elastic air passage 601.

[0045] like Figure 4 and Figure 5As shown, the drive mechanism 602 uses a micro servo motor, which is connected to the transmission mechanism 603 via a coupling to achieve coaxial drive. The transmission mechanism 603 is used to convert the rotational motion of the drive mechanism 602 into the movement motion of the extrusion block 604. The transmission mechanism 603 can be a precision ball screw pair. The end of the extrusion block 604 facing the elastic air passage 601 has an arc surface adapted to the outer wall of the elastic air passage 601. Three extrusion blocks 604 are attached to the outer wall of the elastic air passage 601 circumferentially. The three extrusion blocks 604 are located on the same cross-section of the elastic air passage 601. By synchronously moving radially, the three extrusion blocks 604 extrude the elastic air passage 601, allowing the air passage diameter of the elastic air passage 601 to achieve mechanical stepless contraction.

[0046] In some embodiments, the airway protection module 600 further includes a pressure auxiliary regulating device, which includes a housing 605. One end of the housing 605 is fixed to the base 100, and the other end is sealed to form a pressurization chamber 607. The housing 605 is fitted with an elastic airway tube 601 and a compression assembly. The side wall of the housing 605 is provided with an air inlet 6051, which is used to inject auxiliary pressurizing gas into the pressurization chamber 607. The drive mechanism 602 is fixed to the housing 605.

[0047] like Figure 1 and Figure 4The housing 605 is fixed on the lower base 102 and coaxially arranged with the lower base 102. A fixing plate 606 is provided at the end of the housing 605 away from the lower base 102 to seal the housing 605. The driving component 501 and the driving mechanism 602 are both fixed on the fixing plate 606, or are arranged on the housing 605. The flexible air passage 601 is coaxially installed inside the housing 605. The two ends of the flexible air passage 601 are sealed and connected to the lower base 102 and the fixing plate 606 respectively, and are connected to the output end of the nozzle assembly 400 for laser beam emission processing. The housing 605 is made of rigid material. The two ends of the housing 605 are sealed and connected between the lower base 102 and the fixing plate 606. The inner surface of the housing 605 and the outer surface of the flexible air passage 601 together form a sealed pressurization chamber 607. The air inlet 6051 on the housing 605 is connected to the pressurization chamber 607 and a high-pressure gas source (such as a high-pressure air source). When the orifice of the flexible air passage 601 decreases, the high-pressure gas source starts to supply gas and automatically increases the supply pressure of the auxiliary pressurizing gas. The auxiliary pressurizing gas is injected into the pressurization chamber 607 through the air inlet 6051 to assist the flexible air passage 601 to undergo radial centripetal contraction. When splashed water and residue affect the processing conditions, the air inlet 6051 can be opened, and the extrusion assembly can be used to control the orifice diameter of the elastic air passage 601, providing a basis for adaptive adjustment of the orifice diameter. Under the combined action of the mechanical extrusion of the extrusion assembly and the extrusion of the auxiliary pressurized gas from the pneumatic pressure regulating device, the orifice diameter of the elastic air passage 601 can be linearly adjusted. By precisely controlling the stroke of the extrusion block 604, the diameter of the elastic air passage 601 can be adjusted within its maximum diameter D. max To the minimum diameter D min (D) max The value range is 8.0-15.0 mm, D min The linear switching ranges from 0.5 to 5.0 mm, and is combined with protective gas to maintain a steady flow field within the elastic air passage 601.

[0048] To achieve automatic control of the axial height of the coupling cavity 300 and the aperture of the elastic air passage 601 in the water-guided laser coupling device, the device also includes a control unit. The control unit is communicatively connected to the coupling gap adjustment device 500 and the air passage protection module 600 to control the axial height of the coupling cavity 300 and the aperture of the elastic air passage 601. Specifically, the control unit is communicatively connected to the drive component 501 and the drive mechanism 602 to control the axial movement distance of the inner base 103 via the drive component 501 and the movement distance of the extrusion block 604 via the drive mechanism 602, thereby achieving automatic control.

[0049] Generally, the control unit is an industrial computer. When controlling the drive component 501 and the drive mechanism 602, the industrial computer collects or receives feedback signals and processes the data to issue production control commands. Specifically, the water-guided laser coupling device also includes monitoring components, such as a first displacement sensor 504, a second displacement sensor 608, and a backwater splash volume monitoring sensor 609. Figure 3 The first displacement sensor 504 is mounted on the movable slider 503 to collect the displacement of the movable slider 503 in real time; for example Figure 5 The second displacement sensor 608 is installed on the extrusion block 604 to monitor the displacement of the extrusion block 604 in real time; the backwater splash monitoring sensor 609 is installed on the housing 605 at one end away from the base 100; the first displacement sensor 504, the second displacement sensor 608 and the backwater splash monitoring sensor 609 are respectively connected to the control unit for communication.

[0050] The control unit monitors the processing of the water-guided laser coupling device in real time. Based on the displacement and backwater splash signals received from the first displacement sensor 504, the second displacement sensor 608, and the backwater splash monitoring sensor 609, it controls the coupling gap adjustment device 500 to adjust the axial height of the coupling cavity 300. Simultaneously, it controls the actions of the extrusion assembly and the pneumatic auxiliary adjustment device to adjust the orifice diameter of the elastic air passage 601. It should be noted that the water-guided laser coupling device is also equipped with a laser power detector or laser power meter to collect the laser power of the processing beam and send it to the control unit for real-time monitoring of the laser power. This is existing technology and will not be elaborated upon further.

[0051] The control unit controls the axial height of the coupling cavity 300 by acquiring laser power and feedback signals, combined with... Figure 6 As shown, specifically: The control unit monitors the laser energy in real time through a laser power detector. When the laser power P is detected... t Exceeding the preset laser threshold P th When this happens, the compensation equation of the pre-set coupling cavity 300 is applied. The current axial height H of the coupling cavity 300 is calculated in real time. t The target axial height H of the coupling cavity is 300. th The difference between ; in, This is the heat flow compensation coefficient, which depends on the specific heat capacity and flow rate of the cooling water, and is expressed in μm / W. It is used to calculate the additional water layer thickness required to offset steady-state heat accumulation. For transient response factor, It represents the change in laser power, used to provide feedforward compensation when a sharp increase in power is detected.

[0052] The control unit will calculate the difference. The pulse command is converted into a pulse and sent to the coupling gap adjustment device 500 to adjust the axial height of the coupling cavity 300. The coupling cavity 300 is supplied with high-pressure water by the high-pressure water supply unit to form a water layer with an initial height of H0. The drive unit 501 is activated, and the inner base 103 is moved a distance of ΔH by the moving slider 503 to adjust the axial height of the coupling cavity 300.

[0053] The control unit controls the orifice diameter of the flexible airway tube 601, such as... Figure 6 Specifically: The control unit receives the voltage signal V from the backwater splash monitoring sensor 609. t The voltage signal V t Converted to real-time backwash spray volume M t According to the real-time backflow spray volume M t Determine the target aperture D of the elastic airway tube 601. t ; When the real-time backflow splash volume M is detected t Exceeding the set threshold M th At that time, the control unit, based on the displacement-reverse water volume mapping equation, and based on the real-time reverse water splash volume M, t Calculate the target stroke X of the extrusion block 604: in, The depth-to-diameter ratio protection factor represents the change in real-time backwash spray volume M. t With the set threshold M th As the difference ΔV between them increases, the rate at which the orifice diameter of the elastic airway tube 601 needs to decrease. D is the transmission efficiency coefficient of transmission mechanism 603. max It is the maximum initial aperture of the elastic airway tube 601 in its naturally relaxed state; The control unit sends the target stroke X to the squeezing assembly and air pressure auxiliary adjustment device of the airway protection module 6. Multiple drive mechanisms 602 in the squeezing assembly are started synchronously and drive the squeezing block 604 to move a distance X through the transmission mechanism 603, compressing the orifice of the elastic airway tube 601. At the same time, the high-pressure air source is started and auxiliary pressurizing gas is added to the pressurizing chamber 607 to uniformly pressurize the circumference of the elastic airway tube 601 to ensure the roundness of the elastic airway tube 601. The coupling energy beam protection gas supply unit provides protection gas to ensure that the inner channel of the elastic airway tube 601 still has a stable water flow velocity after compression, thereby realizing the adjustment of the orifice of the elastic airway tube 601.

[0054] Applying the water-guided laser coupling device provided by this invention, combined with Figure 7The adaptive adjustment method for machining micro-holes with large aspect ratios is as follows: S1: Initialization and System Reference Calibration. Before performing the high aspect ratio micro-hole machining task, the control unit first performs a home reset operation on the coupling gap adjustment device 500 and the air passage protection module 600. The coupling gap adjustment device 500 is driven to move the inner base 103 of the nozzle assembly 400 relative to the optical window module 200 fixed in the upper top seat 101 to the initial height H0 of the coupling cavity 300; the extrusion assembly is controlled to be in the released state, and the auxiliary high-pressure gas in the pressurization chamber 607 is emptied, so that the elastic air passage 601 maintains its maximum initial aperture D in a naturally relaxed state. max Afterwards, high-pressure cooling water is injected into the coupling cavity 300 to establish a preliminary laminar flow optical guide channel between the optical window module 200 and the nozzle assembly 400.

[0055] S2: Adaptive adjustment of coupling cavity 300.

[0056] Once the processing stage begins, at the moment the laser emits light, the control unit monitors the laser power P in real time. t And the axial height of the coupling cavity is compensated by calculation.

[0057] When the laser power P t Exceeding the laser's set threshold P th At that time, based on the real-time laser power P t With the set threshold P th The difference between P, calculates the current axial height H of the coupling cavity 300 in real time. t Reaching the target axial height H th (H) th The height difference between the target axial height (assuming both thermal protection and optical-water coupling efficiency of the optical window module 200) under current laser power conditions. This then sends an execution command to the drive unit 501 of the coupling gap adjustment device 500. The height difference... In practical applications, the calculation can also be replaced by PID control or fuzzy control algorithms, and this invention does not impose any restrictions.

[0058] The axial height of the coupling cavity is adaptively adjusted: the drive component 501 drives the moving slider 503 to move axially through the transmission component 502, which causes the inner base 103 where the nozzle assembly 400 is located to move downward along the laser optical axis to generate a micron-level displacement, thereby adjusting the axial height of the coupling cavity 300.

[0059] Adaptive state maintenance of the coupling cavity: If the laser power remains stable for a certain period of time and the optical-water coupling efficiency reaches a high level, the control unit sends a command to the drive component 501 to lock the position of the currently moving slider 503, completing one adaptive adjustment cycle for energy fluctuations. When the laser power changes, the control unit controls the coupling gap adjustment device 500 to repeat the adjustment control of step S2 above.

[0060] S3: Real-time monitoring of water splash volume.

[0061] A backwash splash volume monitoring sensor 609 is arranged at the bottom of the housing 605 of the airway protection module 600. The backwash volume is monitored in real time by detecting the dynamic load generated by the impact of splashes on the surface of the backwash splash volume monitoring sensor 609. During the processing, when backwash water (including splashed water and residue) impacts the sensitive area of ​​the backwash splash volume monitoring sensor 609, the piezoelectric film in the backwash splash volume monitoring sensor 609 deforms under force and generates an electric charge signal proportional to the magnitude of the impact force. This signal is converted into a voltage signal V by the built-in charge amplifier. t The data is then transmitted to the control unit (such as an industrial computer) for status determination.

[0062] S4: Airway protection module 600 adaptive adjustment.

[0063] Deep hole protection mode determination and triggering: The control unit will determine the real-time voltage signal V. t Converted to real-time backwash spray volume M t (This can be based on the equation corresponding to the voltage signal and the amount of water splashing) (Obtained through test calibration.) When the real-time backflow splash volume M is detected... t Exceeding the set threshold M th When the risk of backflow splashing interfering with the processing operation is significantly increased, the system switches to deep hole protection mode. The control unit controls the airway protection module 600 to start and perform diameter adjustment.

[0064] Airway protection module 600 adaptive adjustment: The control unit adjusts according to the real-time backflow spray volume M t Determine the target stroke X of the extrusion block 604 and the target orifice D of the elastic air passage 601. tSubsequently, the control unit synchronously sends position commands to the three drive mechanisms 602. Each of the three drive mechanisms 602, through its respective transmission mechanism 603, drives the three compression blocks 604 to advance a preset distance X at the same rate, radially compressing the elastic air passage tube 601. Simultaneously, the pneumatic pressure assist regulating device injects auxiliary high-pressure gas into the pressurizing chamber 607 through the air inlet 6051, assisting the radial contraction of the elastic air passage tube 601 and ensuring the roundness of the cross-section. This allows the hydrostatic pressure to act evenly on the outer wall of the elastic air passage tube 601. Under the combined action of mechanical thrust and pneumatic assist, the elastic air passage tube 601 smoothly undergoes radial-centripetal contraction, with the orifice diameter decreasing from its initial maximum state D. max Smoothly and steplessly switch to the target aperture D corresponding to the current working condition. t This ensures both the precision of aperture adjustment and the ability to maintain the roundness of the airway cross-section after contraction through air pressure assistance.

[0065] Protective gas compensation: During the above adjustment process, the coupling energy beam protective gas supply unit is linked in a closed loop with the extrusion assembly and the pressurization chamber 607. As the orifice of the elastic air passage 601 decreases, the coupling energy beam protective gas supply unit automatically increases the protective gas supply pressure and provides protective gas through the protective gas channel 1012 to maintain a constant airflow velocity in the elastic air passage 601, thereby achieving protective gas compensation.

[0066] The control unit acquires the displacement feedback signals from the first displacement sensor 504 and the second displacement sensor 608 in real time and performs real-time adjustment and control.

[0067] S5: System standby reset. When the micro-hole processing task is completed, the extrusion assembly and the air pressure auxiliary adjustment device release pressure first, causing the elastic air passage 601 to quickly reset to its initial state. The coupling gap adjustment device 500 then drives the coupling cavity 300 to reset. The control unit initiates a high-flow-rate purging process to clean any residue or splashes that may be present in the elastic air passage 601, completing a full closed-loop processing cycle.

[0068] Through the above processing, the water-guided laser coupling device provided by the present invention realizes the adaptive state maintenance of the coupling cavity 300 and the adaptive adjustment of the gas passage protection module 600, and has protective gas pressure compensation, full-process closed-loop reset and automatic cleaning, providing a reliable equipment support for the processing of micro-holes with large aspect ratio.

[0069] During normal operation of the water-guided laser coupling device, the optical window module 200 needs to maintain complete light transmission. In existing water-guided laser coupling devices, due to the fixed water layer value in the coupling cavity 300, if the laser power increases during the processing of micro-holes with large aspect ratios, prolonged high-power operation will increase the thermal load on the optical window module 200, making it susceptible to thermal damage or breakage. Figure 8As shown. Under the same processing conditions, using the water-guided laser coupling device of the present invention, as the laser power increases, the thickness of the water layer inside the coupling cavity 300 can be adaptively adjusted according to the change in laser power, thereby effectively reducing the risk of thermal damage and breakage of the optical window module 200, such as... Figure 9 As shown, the optical window module 200 remains intact; at the same time, the water layer thickness is adjusted adaptively to meet the target coupling state under the current working conditions, thereby improving the coupling state between the laser and the water beam and enhancing coupling stability. When performing micro-hole processing with a large aspect ratio, the water-guided laser coupling device provided in this embodiment of the invention can achieve a laser beam length of 19cm, provided that the optical window module 200 is undamaged and the laser power meets the processing requirements.

[0070] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A water-guided laser coupling device, characterized in that, include: A base (100) having an internal mounting cavity; An optical window module (200) is disposed within the mounting cavity; A nozzle assembly (400) is disposed in the mounting cavity and spaced apart from the optical window module (200). A coupling cavity (300) is formed between the optical window module (200) and the nozzle assembly (400). The axial height of the coupling cavity (300) is adjustable. An airway protection module (600) is installed on the base (100) and located at the output end of the nozzle assembly (400). The airway protection module (600) includes an elastic airway tube (601), which is coaxially arranged with the nozzle assembly (400). The orifice diameter of the elastic airway tube (601) is adjustable.

2. The water-guided laser coupling device according to claim 1, characterized in that, It also includes a coupling gap adjustment device (500), which is disposed on the base (100) and connected to the nozzle assembly (400). The coupling gap adjustment device (500) is configured to drive the nozzle assembly (400) to move along the axial direction of the mounting cavity to adjust the axial height of the coupling cavity (300).

3. The water-guided laser coupling device according to claim 2, characterized in that, The base (100) includes an inner base (103), which is slidably disposed in the mounting cavity. The nozzle assembly (400) is disposed on the inner base (103). The coupling gap adjustment device (500) is connected to the inner base (103) to drive the inner base (103) to drive the nozzle assembly (400) to move axially.

4. The water-guided laser coupling device according to claim 3, characterized in that, The coupling gap adjustment device (500) includes: A driving member (501) is disposed on the base (100) and located on the outside of the base (100); A transmission assembly (502) is disposed at the output end of the drive member (501), and the transmission assembly (502) is disposed through the base (100) from the outside to the inside; A movable slider (503) is fixedly connected to the inner base (103). The movable slider (503) is located at one end of the transmission assembly (502) away from the driving member (501). The driving member (501) drives the movable slider (503) to move axially through the transmission assembly (502).

5. The water-guided laser coupling device according to claim 4, characterized in that, The transmission assembly (502) includes a ball screw pair, which includes a screw shaft and a nut seat. The nut seat is fixedly mounted on the movable slider (503). One end of the screw shaft is connected to the output end of the drive unit (501), and the other end of the screw shaft is engaged with the nut seat. When the drive unit (501) drives the screw shaft to rotate, the nut seat drives the movable slider (503) to move axially.

6. The water-guided laser coupling device according to claim 3, characterized in that, A linear guide rail (104) is provided between the inner base (103) and the side wall of the mounting cavity in the circumferential direction.

7. The water-guided laser coupling device according to claim 3, characterized in that, The inner base (103) has a stepped surface (1031) on its side facing the output end of the nozzle assembly (400). When the inner base (103) moves toward the optical window module (200) and has a minimum axial height in the coupling cavity (300), the stepped surface (1031) abuts against the inner wall of the mounting cavity.

8. The water-guided laser coupling device according to claim 3, characterized in that, An elastic element (105) is provided between the end face of the inner base (103) facing the output end of the nozzle assembly (400) and the inner wall of the mounting cavity.

9. The water-guided laser coupling device according to claim 4, characterized in that, The airway protection module (600) also includes a plurality of compression components, which are evenly spaced around the elastic airway tube (601) in the circumferential direction. The output end of the compression component can move toward or away from the elastic airway tube (601). When the output end of the compression component moves toward the elastic airway tube (601), it can compress the elastic airway tube (601) to shrink the aperture of the elastic airway tube (601).

10. The water-guided laser coupling device according to claim 9, characterized in that, The extrusion assembly includes: A drive mechanism (602) is provided with its output end arranged along the radial direction of the elastic airway tube (601); A transmission mechanism (603), one end of which is connected to the output end of the drive mechanism (602); A compression block (604) is provided at one end of the transmission mechanism (603) away from the drive mechanism (602). The drive mechanism (602) can drive the compression block (604) to move toward the elastic airway tube (601) through the transmission mechanism (603) to compress the elastic airway tube (601).

11. The water-guided laser coupling device according to claim 10, characterized in that, The airway protection module (600) further includes a pressure auxiliary regulating device, which includes a housing (605). One end of the housing (605) is fixed to the base (100), and the other end is sealed to form a pressurization chamber (607). The housing (605) is fitted with the elastic airway tube (601) and the compression assembly. The side wall of the housing (605) is provided with an air inlet (6051), which is used to inject auxiliary pressurizing gas into the pressurization chamber (607). The drive mechanism (602) is fixed to the housing (605).

12. The water-guided laser coupling device according to claim 11, characterized in that: It also includes a control unit, which is communicatively connected to the coupling gap adjustment device (500) and the airway protection module (600) to control the axial height of the coupling cavity (300) and the aperture of the elastic airway tube (601).

13. The water-guided laser coupling device according to claim 12, characterized in that: It also includes a monitoring component, which includes: A first displacement sensor (504) is disposed on the movable slider (503); A second displacement sensor (608) is disposed on the extrusion block (604); A backwater splash monitoring sensor (609) is disposed on the housing (605) at one end away from the base (100); The first displacement sensor (504), the second displacement sensor (608), and the backwater splash monitoring sensor (609) are respectively connected to the control unit in communication.

14. The water-guided laser coupling device according to claim 13, characterized in that: The control unit controls the axial height of the coupling cavity (300), specifically: The control unit monitors the laser energy in real time, and when the laser power P is detected... t Exceeding the preset laser threshold P th When this happens, the compensation equation of the pre-set coupling cavity (300) is applied. The current axial height H of the coupling cavity (300) is calculated in real time. t The target axial height H of the coupling cavity (300) is reached th The difference between ; in, This is the heat flow compensation coefficient. For transient response factor, This represents the change in laser power. The control unit will calculate the difference. The pulse command is converted into a pulse and sent to the coupling gap adjustment device (500) to adjust the axial height of the coupling cavity (300).

15. The water-guided laser coupling device according to claim 14, characterized in that: The control unit controls the aperture of the elastic airway tube (601), specifically: The control unit receives the voltage signal V from the backwater splash monitoring sensor (609). t The voltage signal V t Converted to real-time backwash spray volume M t According to the real-time backflow spray volume M t Determine the target aperture D of the elastic airway tube (601). t ; When the real-time backflow splash volume M is detected t Exceeding the set threshold M th At that time, the control unit calculates the real-time backwater splash volume M. t Calculate the target stroke X of the extrusion block (604): in, The depth-to-diameter ratio protection factor, D is the transmission efficiency coefficient of the transmission mechanism (603). max The elastic airway tube (601) is kept in its maximum initial aperture under natural relaxation. The control unit sends the target stroke X to the extrusion assembly.

Images