A laser processing head for chemical milling protective glue, a processing system and a type carving method

Abstract

The application belongs to the technical field of laser engraving, and specifically discloses a laser processing head for chemical milling protective glue, a processing system and an engraving method, which comprises the following steps: obtaining a pre-built thickness conversion model and processing parameters, and determining a current laser processing point P1; making a confocal measurement point P2 fall on a processing track in front of P1; obtaining the glue layer surface distance of an unprocessed area in advance at P2, establishing a space-time matching relationship with the physical track position and caching; when P1 moves to the corresponding physical position of P2, the metal reference equivalent distance at the position is obtained by using a capacitive sensor; the matched glue layer surface distance is extracted, the metal reference equivalent distance is combined, the thickness conversion model is substituted, the current protective glue layer thickness is calculated, and the laser processing parameters are dynamically adjusted accordingly. The problems of distance measuring point deviation and processing smoke interference in complex surface processing are effectively overcome, and precise online measurement and calculation of the glue layer thickness and self-adaptive closed-loop regulation and control of the laser energy are realized.

Description

Technical Field

[0001] This invention belongs to the field of laser engraving technology, specifically relating to a laser processing head, processing system, and engraving method for chemical milling protective adhesive. Background Technology

[0002] In the aerospace manufacturing field, chemical milling is commonly used to achieve weight reduction for thin-walled metal structural components such as casings and skins. Before chemical milling, a protective adhesive is applied to the surface of the metal substrate, and a predetermined pattern is etched onto the adhesive layer using a multi-axis CNC laser to remove localized adhesive layers. Laser engraving, with its digital and flexible characteristics, has become an important method for pre-processing complex curved surface parts before chemical milling.

[0003] Since the protective adhesive is mostly applied manually, its thickness often fluctuates significantly on complex curved surfaces. To avoid localized overheating or adhesive residue caused by a fixed laser power, existing laser engraving equipment often incorporates optical sensors to obtain the thickness of the processing area. Currently, coaxial ranging or fixed off-axis ranging schemes are mainly used. The former ensures that the measuring beam and the processing beam pass coaxially through the focusing lens; the latter fixes the ranging sensor to the side of the laser processing head, measuring the distance to the adhesive layer surface on the side during processing, which serves as the basis for adjusting subsequent laser processing parameters.

[0004] However, existing technologies encounter the following problems in practical applications: First, when using a coaxial ranging scheme, the measuring beam needs to pass through the area being processed. The smoke, plasma, and carbonized residue generated by laser ablation of the protective adhesive significantly interfere with the optical measurement signal, leading to deviations in the acquired distance data. Second, when using a fixed off-axis ranging scheme to process complex curved surfaces, the measurement point of the side sensor drifts relative to the actual processing trajectory as the machine tool head's posture continuously changes. This causes the measured position to deviate from the path to be processed, and the collected distance information cannot accurately correspond to the state when the laser reaches that point, resulting in thickness calculation errors and affecting the protective effect on the underlying metal substrate. Summary of the Invention

[0005] This invention addresses the problems in the prior art by providing a laser processing head, processing system, and engraving method for chemical milling protective adhesives. It solves the problem in the prior art where, using a coaxial ranging scheme, the measuring beam must pass through the area being processed. The smoke, plasma, and carbonized adhesive layer generated by laser ablation of the protective adhesive significantly interfere with the optical measurement signal, leading to deviations in the acquired distance data. Simultaneously, it solves the problem in the prior art where, when processing complex curved surfaces using a fixed off-axis ranging scheme, the measurement point of the side sensor drifts relative to the actual processing trajectory as the machine tool head's posture continuously changes, causing the measured position to deviate from the path to be processed. This results in the collected distance information not accurately corresponding to the state when the laser reaches that point, leading to thickness measurement errors and affecting the protective effect on the underlying metal substrate.

[0006] The technical solution adopted in this invention is as follows: In a first aspect, this application provides a laser processing head for chemical milling protective adhesives, comprising: The main processing component includes a laser processing optical path, an A-axis motor with an output end, and a C-axis motor with an output end. The output end of the A-axis motor controls the movement of the A-axis, and the output end of the C-axis motor controls the movement of the C-axis. The laser processing optical path emits a laser beam along the optical axis direction. A capacitive ranging sensor is located at the end of the main processing assembly, with its detection surface facing the focal point of the laser beam, to collect the equivalent distance of a metal reference in the focal point region. ; A side-axis confocal sensor, comprising a confocal sensor fixture, wherein the side-axis confocal sensor is offsetly disposed on the side of the laser processing optical path via the confocal sensor fixture, and the angle between its measuring optical axis and the laser processing optical axis is a set installation angle; The confocal sensor attitude control motor has its stator fixed relative to the main machining assembly, and its rotor mechanically connected to the confocal sensor fixture. The confocal sensor attitude control motor receives drive electrical signals and drives the off-axis confocal sensor to rotate around the laser processing optical axis through the rotor.

[0007] Furthermore, it also includes: The voice coil motor is installed in the laser processing optical path with a focusing lens. The fixed end of the voice coil motor is installed in the main processing component, and the movable end is mechanically connected to the lens mount of the focusing lens. It receives the input current signal and drives the focusing lens to move linearly along the laser processing optical axis.

[0008] Furthermore, it also includes: An imaging module, whose optical axis is coaxially arranged or biased and fixed on one side of the main processing component with the laser processing optical path, acquires and outputs reflected optical image signals passing through the area affected by the laser beam.

[0009] Secondly, this application provides a processing system, including the processing head described in the first aspect, and further comprising: The memory contains preset processing head structure size parameters, confocal sensor bias parameters, thickness conversion model characterizing the numerical mapping relationship between adhesive layer surface distance and metal reference equivalent distance and protective adhesive layer thickness, as well as multi-axis CNC machining programs. The controller includes a microprocessor and a communication interface, and is electrically connected to the A-axis motor, the C-axis motor, the confocal sensor attitude control motor, the capacitive ranging sensor, the off-axis confocal sensor, and the trigger end of the laser processing optical path, respectively.

[0010] Furthermore, the controller reads the coordinate and angle data fed back from the machine tool axis and executes the multi-axis CNC machining program to determine the coordinate system position of the current laser processing point P1 and the confocal measurement point P2; The controller outputs a drive signal to the attitude control motor of the confocal sensor, driving the off-axis confocal sensor to rotate to the azimuth angle corresponding to P2; The controller reads the distance signal output by the off-axis confocal sensor as the distance to the adhesive layer surface. A cache queue is established in the memory, and the electrical signal of the capacitive ranging sensor is extracted as the equivalent distance of the metal reference when the interpolated coordinates reach the physical position corresponding to P2. ; The controller extracts the corresponding value from the cache queue. With the current description The thickness value is obtained by substituting it into the thickness conversion model, and a control signal with modulation parameters is generated and sent to the trigger end of the laser processing optical path.

[0011] Thirdly, this application provides a laser engraving method for chemical milling protective adhesives, using the processing system described in the second aspect, comprising the following steps: Step S1: Obtain the structural dimension parameters of the processing head, the attitude transformation relationship between the A-axis and C-axis, the installation angle of the off-axis confocal sensor, the installation offset of the off-axis confocal sensor relative to the laser processing optical axis, and the pre-established thickness conversion model. The thickness conversion model characterizes the numerical mapping relationship between the adhesive layer surface distance, the metal reference equivalent distance, the sensor installation parameters and the protective adhesive layer thickness. Step S2: Obtain the machining trajectory, machining speed, machine tool motion axis position, and current A-axis angle and current C-axis angle; Step S3: Determine the current laser processing point P1 based on the processing head structure size parameters, the current A-axis angle, and the current C-axis angle. P1 is located on the processing trajectory. Step S4: Calculate the confocal sensor attitude control angle based on the feed direction of the machining trajectory, the current A-axis angle, the current C-axis angle, and the mounting offset. Rotate and adjust the off-axis confocal sensor to the confocal sensor attitude control angle so that the corresponding confocal measurement point P2 falls on the machining trajectory in front of P1. Step S5: Calculate the trajectory spacing between P1 and P2 along the machining trajectory. The distance between the adhesive layer surface and the unprocessed area at P2 is obtained using the paraxial confocal sensor. ; Step S6: Based on the trajectory spacing The distance between the adhesive layer surfaces is established based on the processing speed. The spatiotemporal matching relationship between the physical trajectory position and the distance to the adhesive layer surface. Cache; Step S7: When P1 moves to the physical trajectory position corresponding to P2, the equivalent distance of the metal reference at that physical trajectory position is obtained using a capacitive ranging sensor. ; Step S8: Extract the cached data. , will the The above The thickness of the protective adhesive layer at the current position is calculated by substituting the installation angle into the thickness conversion model. ; Step S9: Based on the thickness of the protective adhesive layer The command to generate laser processing parameters is issued to execute laser engraving.

[0012] Furthermore, the off-axis confocal sensor is controlled to rotate around the laser processing optical axis, and the rotation is independent of the transmission path and focusing position of the laser processing optical path.

[0013] Furthermore, the trajectory spacing The arc length distance between P1 and P2 is calculated along the processing trajectory curve; The specific steps for establishing the spatiotemporal matching relationship and caching include: when the processing speed is a constant value. At that time, according to Calculate the The time lead relative to P1 is used as the matching benchmark; When the processing speed is not constant, the real-time speed is integrated or the value is established based on the CNC interpolation cycle. Mapping the coordinates to the physical trajectory and caching them.

[0014] Furthermore, in step S8, the thickness conversion model is specifically as follows: Using calibration function Calculate the thickness of the protective adhesive layer ,in The current A-axis angle, The current C-axis angle, The attitude control angle of the confocal sensor. The installation angle is mentioned above; Alternatively, a linear formula can be used. Calculate the thickness of the protective adhesive layer ,in and These are pre-calibrated coefficients.

[0015] Furthermore, step S5 also includes: Obtain the normal deviation distance of P2 relative to the machining trajectory. When the normal deviation distance exceeds a preset threshold range, the corresponding position obtained at that location is... Marked as low confidence data.

[0016] As can be seen from the above technical solutions, the advantages of the present invention are: By acquiring a pre-established thickness conversion model and controlling the off-axis confocal sensor to dynamically adjust the measurement orientation according to the machining head posture to obtain the surface distance in advance, and then combining the equivalent distance of the metal reference obtained by the capacitive distance sensor with the spatiotemporal matching relationship to calculate the thickness, stable tracking and anti-interference dual ranging of the measurement point are realized in the process of complex curved surface engraving. The laser parameters can be dynamically adjusted according to the accurately acquired real-time thickness to reduce the risk of thermal damage to the underlying metal.

[0017] By controlling the off-axis confocal sensor to rotate around the laser processing optical axis, and with the rotation action independent of the transmission path and focusing position of the laser processing optical path, flexible adjustment of the measurement orientation can be achieved without changing the optical characteristics of the main laser processing optical path, thus avoiding interference of the ranging mechanism's movement on the laser energy distribution and transmission accuracy.

[0018] By calculating the arc length spacing along the processing trajectory curve and establishing a cache mapping between distance data and physical coordinates based on the constant or changing state of processing speed, the surface distance data and substrate distance data collected at different time nodes and spatial locations are accurately aligned, which can effectively improve the spatial accuracy of thickness calculation.

[0019] By employing a calibration function that includes multi-axis angles and attitude control angles, or by using a linear formula based on sensor mounting bias to calculate the thickness of the protective adhesive layer, the measurement error caused by the change of the spatial normal of complex curved surfaces is corrected, which can meet the needs of accurate thickness conversion under different spatial processing postures.

[0020] By acquiring the normal deviation distance of the confocal measurement point relative to the processing trajectory, and marking the surface distance data as low-confidence data when the deviation distance exceeds a preset threshold, the validity of the distance measurement data is automatically filtered, which can avoid thickness calculation errors and laser parameter misadjustment caused by local derailment of the measurement point.

[0021] By setting the laser processing parameters to one or more of the following parameters: laser power, duty cycle, repetition frequency, pulse width, and scanning speed, multi-dimensional fine control of laser input energy is achieved, enabling precise output of matching removal doses for adhesive layers with varying thicknesses.

[0022] By setting a capacitive ranging sensor to directly acquire the distance to the metal reference in the main processing component, and configuring a confocal sensor attitude control motor to drive the side confocal sensor to rotate dynamically around the optical axis, a hardware configuration is achieved in which the ranging point is always in front of the current processing point trajectory, which can provide composite ranging support that is resistant to smoke and dust interference and has adaptive tracking capability.

[0023] By setting a voice coil motor mechanically connected to the focusing lens in the laser processing optical path and driving the focusing lens to move linearly along the optical axis, dynamic high-frequency adjustment of the laser focus is achieved, which can maintain the relative stability of the laser focus position when the surface morphology of the workpiece fluctuates or the gap changes.

[0024] By setting an imaging module coaxially or laterally offset on the main processing components, the reflected optical image signal passing through the laser beam action area is collected, realizing the synchronous optical data acquisition of the actual removal state of the protective adhesive layer after the engraving process. This can provide visual data basis for subsequent processing quality assessment or closed-loop re-engraving.

[0025] By integrating a memory that stores the thickness conversion model and CNC machining program, and configuring a controller that is electrically connected to each motion axis motor, attitude control motor and each measurement sensor, integrated hardware collaborative scheduling of feedforward point finding, dual-path ranging, data matching and laser control processes in the continuous machining of complex curved surfaces is realized. Attached Figure Description

[0026] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the structure of a laser processing head for chemical milling protective adhesive according to an embodiment of the present invention; Figure 2 This is a partial structural diagram of a laser processing head for chemical milling of protective adhesive according to an embodiment of the present invention. Figure 1 ; Figure 3 This is a partial structural diagram of a laser processing head for chemical milling of protective adhesive according to an embodiment of the present invention. Figure 2 ; Figure 4 This is a schematic diagram of the processing system according to an embodiment of the present invention; Figure 5 This is a framework diagram of the processing system according to an embodiment of the present invention.

[0028] Figure 6 This is a flowchart of a laser engraving method for chemical milling protective adhesive according to an embodiment of the present invention.

[0029] In the diagram: 1. Laser module; 2. Collimation module; 3. Imaging module; 4. Dichroic mirror; 5. C-axis motor; 6. First reflecting mirror; 7. A-axis motor; 8. Voice coil motor; 9. Second reflecting mirror; 10. Focusing mirror; 11. Confocal sensor attitude control motor; 12. Confocal sensor fixture; 13. Off-axis confocal sensor; 14. Capacitive ranging sensor; 15. Controller; 16. Chemical milling protective adhesive; 17. Metal substrate; m, capacitive ranging; n, optical ranging. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Please see Figures 1-3 As shown, this application provides a laser processing head for chemical milling protective adhesive, comprising: The main processing component includes a laser processing optical path, an A-axis motor 7 with an output end, and a C-axis motor 5 with an output end. The output end of the A-axis motor 7 controls the movement of the A-axis, and the output end of the C-axis motor 5 controls the movement of the C-axis. The laser processing optical path emits a laser beam along the optical axis direction. A capacitive ranging sensor 14 is located at the end of the main processing component to realize capacitive ranging m. Its detection surface faces the focal position of the laser beam and collects the metal reference equivalent distance de in the focal position area. A side-axis confocal sensor 13 includes a confocal sensor fixture 12. The side-axis confocal sensor 13 is biased and disposed on the side of the laser processing optical path through the confocal sensor fixture 12. The angle between its measuring optical axis and the laser processing optical axis is a set installation angle to realize optical ranging n. The confocal sensor attitude control motor 11 has its stator fixed relative to the main processing assembly, and its rotor mechanically connected to the confocal sensor fixture 12. The confocal sensor attitude control motor 11 receives a drive electrical signal and drives the off-axis confocal sensor 13 to rotate around the laser processing optical axis through the rotor.

[0032] In some embodiments, it also includes: The voice coil motor 8 is installed in the laser processing optical path, and a focusing lens 10 is provided inside the laser processing optical path. The fixed end of the voice coil motor 8 is installed in the main processing component, and the movable end is mechanically connected to the lens mount of the focusing lens 10. It receives the input current signal and drives the focusing lens 10 to move linearly along the laser processing optical axis.

[0033] In some embodiments, it also includes: Imaging module 3, whose optical axis is coaxial with or biased and fixed on one side of the main processing component, acquires and outputs reflected optical image signals passing through the area affected by the laser beam.

[0034] Please see Figure 4 and Figure 5 As shown, this application provides a processing system, which further includes: The memory contains preset processing head structure size parameters, confocal sensor bias parameters, thickness conversion model characterizing the numerical mapping relationship between adhesive layer surface distance and metal reference equivalent distance and protective adhesive layer thickness, as well as multi-axis CNC machining programs. The controller 15 includes a microprocessor and a communication interface, and is electrically connected to the A-axis motor 7, the C-axis motor 5, the confocal sensor attitude control motor 11, the capacitive ranging sensor 14, the off-axis confocal sensor 13, and the trigger end of the laser processing optical path.

[0035] Before the formal engraving process, the controller 15 calibrates the machining head and measurement link. The calibration includes: the attitude transformation relationship between the A-axis, C-axis and the machine tool motion axes; the structural dimension parameters L1, L2, and L3 of the laser machining point P1 relative to the A / C double pendulum axis mechanism; the installation offset parameter ds and installation angle dθ of the off-axis confocal sensor 13 relative to the machining optical axis; the correspondence between the confocal sensor attitude control angle φ and the position of the confocal measurement point P2; the conversion relationship between the zero position, range and metal reference equivalent distance de of the capacitive distance sensor 14; and the thickness conversion relationship for calculating the adhesive layer thickness h from dl, dθ and de.

[0036] Calibration can be performed using standard flat specimens, protective adhesive specimens of known thickness, bare metal reference surfaces, or calibration areas on actual parts. For complex curved surface parts, confocal ranging values, capacitance ranging values, and known adhesive layer thicknesses can be collected under several typical A / C axis attitudes to establish segmented lookup tables, linear compensation, or multi-parameter calibration models. During machining, the controller 15 calls up the above calibration data, without temporarily changing the measurement definitions, and only performs real-time matching and correction based on the current trajectory position and attitude.

[0037] During the calibration process, the allowable range of forward distances and the range of track-landing errors for measurement points can also be determined. When the deviation between the forward measurement point P2 and the processing trajectory exceeds the allowable range, the control system 15 can recalculate the confocal sensor attitude control angle φ, or mark the measurement data as low-confidence data and not use it as the main basis for calculating the adhesive layer thickness.

[0038] In some embodiments, the controller 15 reads the coordinate and angle data fed back from the machine tool axis and executes the multi-axis CNC machining program to determine the coordinate system position of the current laser processing point P1 and the confocal measurement point P2; The controller 15 outputs a drive signal to the confocal sensor attitude control motor 11, driving the off-axis confocal sensor 13 to rotate to the azimuth angle corresponding to P2. The controller 15 reads the distance signal output by the off-axis confocal sensor 13 as the adhesive surface distance dl and establishes a cache queue in the memory. When the interpolation coordinates reach the physical position corresponding to P2, the controller 15 extracts the electrical signal of the capacitive distance sensor 14 as the metal reference equivalent distance de. The controller 15 extracts the corresponding dl and the current de from the cache queue, substitutes them into the thickness conversion model to obtain the thickness value result, and generates a control signal with modulation parameters to send to the trigger end of the laser processing optical path.

[0039] The processing head body includes a main processing assembly, which internally forms a complete laser processing optical path and a spatial attitude adjustment mechanism. Specifically: The system includes a laser module 1, which generates the laser beam required for processing. After being emitted, the laser beam is first collimated by a collimation module 2, and then projected onto a dichroic mirror 4. The dichroic mirror 4 reflects and deflects the laser beam downwards into the subsequent optical path, while allowing the reflected visible light / illumination light to be transmitted upwards into the imaging module 3. The optical axis of the imaging module 3 is coaxial with the laser processing optical path, and is used to acquire reflected optical image signals from the area affected by the laser beam and output them to the controller 15, so as to monitor or visually align the actual removal status of the protective adhesive layer after the engraving process.

[0040] After being deflected by the dichroic mirror 4, the laser beam is transmitted downwards, passing sequentially through the internal hollow channel of the C-axis motor 5, the deflection of the first reflector 6, and the internal channel of the A-axis motor 7, before finally being projected onto the second reflector 9. The outputs of the C-axis motor 5 and the A-axis motor 7 work together to form a double-axis structure, used to adjust the spatial orientation of the machining head in real time according to the shape of complex curved workpieces.

[0041] The second reflecting mirror 9 deflects the laser beam downwards, directing it toward the focusing mirror 10. The focusing mirror 10's mount is mechanically connected to the movable end of the voice coil motor 8, while the fixed end of the voice coil motor 8 is mounted on the main processing assembly housing. The voice coil motor 8 receives the input current signal from the controller 15, driving the focusing mirror 10 to undergo linear displacement along the laser processing optical axis, achieving high-frequency dynamic fine-tuning of the focal position. The focused laser beam ultimately exits from the inner hole of the capacitive distance sensor 14 located at the very end of the processing head. The detection surface of the capacitive distance sensor 14 faces the focal position of the laser beam. Since the capacitive distance principle is insensitive to non-conductive protective adhesive layers, it is mainly used to penetrate the adhesive layer and directly acquire the equivalent distance of the metal reference in the focal position area (i.e., the current processing point).

[0042] A dynamic surface ranging mechanism is also configured at the end of the main processing assembly. This mechanism includes a confocal sensor attitude control motor 11, whose stator is fixed relative to the main processing assembly, and whose rotor is mechanically connected to the confocal sensor fixture 12. A side-axis confocal sensor 13 is fixedly clamped on the confocal sensor fixture 12. Thus, the side-axis confocal sensor 13 is offset to the side of the laser processing optical path, and the angle between its measuring optical axis and the laser processing optical axis is a fixed installation angle. The confocal sensor attitude control motor 11 receives the drive electrical signal from the controller 15 and drives the side-axis confocal sensor 13 to rotate around the laser processing optical axis through its rotor. This rotation only changes the azimuth angle of the side-axis confocal sensor 13 in the circumferential direction of the laser optical axis, independent of the transmission path and focusing position inside the laser processing optical path, and will not cause optical interference to the laser processing.

[0043] The system can provide an initial laser energy based on h, so that the chemical milling protective adhesive 16 is removed close to the metal substrate 17; during the confirmation stage, the imaging module 3 acquires the reflection image of the etched area under modulated illumination or auxiliary light source conditions, and judges the adhesive layer removal status based on the reflection brightness, color or texture characteristics, and can fine-tune the laser energy.

[0044] Please see Figure 6 As shown, this application provides a laser engraving method for chemical milling protective adhesive, the method comprising the following steps: Step S1: Obtain the structural dimension parameters of the processing head, the attitude transformation relationship between the A-axis and C-axis, the installation angle of the off-axis confocal sensor, the installation offset of the off-axis confocal sensor relative to the laser processing optical axis, and the pre-established thickness conversion model. The thickness conversion model characterizes the numerical mapping relationship between the adhesive layer surface distance, the metal reference equivalent distance, the sensor installation parameters and the protective adhesive layer thickness. Step S2: Obtain the machining trajectory, machining speed, machine tool motion axis position, and current A-axis angle and current C-axis angle; Step S3: Determine the current laser processing point P1 based on the processing head structure size parameters, the current A-axis angle, and the current C-axis angle. P1 is located on the processing trajectory. Step S4: Calculate the confocal sensor attitude control angle based on the feed direction of the machining trajectory, the current A-axis angle, the current C-axis angle, and the mounting offset. Rotate and adjust the off-axis confocal sensor to the confocal sensor attitude control angle so that the corresponding confocal measurement point P2 falls on the machining trajectory in front of P1. Step S5: Calculate the trajectory spacing between P1 and P2 along the machining trajectory. The distance between the adhesive layer surface and the unprocessed area at P2 is obtained using the paraxial confocal sensor. ; Step S6: Based on the trajectory spacing The distance between the adhesive layer surfaces is established based on the processing speed. The spatiotemporal matching relationship between the physical trajectory position and the distance to the adhesive layer surface. Cache; Step S7: When P1 moves to the physical trajectory position corresponding to P2, the equivalent distance of the metal reference at that physical trajectory position is obtained using a capacitive ranging sensor. ; Step S8: Extract the cached data. , will the The above The thickness of the protective adhesive layer at the current position is calculated by substituting the installation angle into the thickness conversion model. ; Step S9: Based on the thickness of the protective adhesive layer The command to generate laser processing parameters is issued to execute laser engraving.

[0045] In some embodiments, the off-axis confocal sensor is controlled to rotate around the laser processing optical axis, and the rotation is independent of the transmission path and focusing position of the laser processing optical path.

[0046] In some embodiments, the trajectory spacing The arc length distance between P1 and P2 is calculated along the processing trajectory curve; The specific steps for establishing the spatiotemporal matching relationship and caching include: when the processing speed is a constant value. At that time, according to Calculate the The time lead relative to P1 is used as the matching benchmark; When the processing speed is not constant, the real-time speed is integrated or the value is established based on the CNC interpolation cycle. Mapping the coordinates to the physical trajectory and caching them.

[0047] In some embodiments, in step S8, the thickness conversion model specifically refers to: Using calibration function Calculate the thickness of the protective adhesive layer ,in The current A-axis angle, The current C-axis angle, The attitude control angle of the confocal sensor. The installation angle is mentioned above; Alternatively, a linear formula can be used. Calculate the thickness of the protective adhesive layer ,in and These are pre-calibrated coefficients.

[0048] In some embodiments, step S5 further includes: Obtain the normal deviation distance of P2 relative to the machining trajectory. When the normal deviation distance exceeds a preset threshold range, the corresponding position obtained at that location is... Marked as low confidence data.

[0049] The above description is merely a preferred embodiment of one or more embodiments of this specification and is not intended to limit the scope of one or more embodiments of this specification. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments of this specification should be included within the protection scope of one or more embodiments of this specification.

Claims

1. A laser processing head for chemical milling protective adhesive, characterized in that, include: The main processing component includes a laser processing optical path, an A-axis motor (7) with an output end, and a C-axis motor (5) with an output end. The output end of the A-axis motor (7) controls the movement of the A-axis, and the output end of the C-axis motor (5) controls the movement of the C-axis. The laser processing optical path emits a laser beam along the optical axis direction. A capacitive ranging sensor (14) is located at the end of the main processing assembly, with its detection surface facing the focal position of the laser beam, and collects the metal reference equivalent distance de in the focal position area; A side-axis confocal sensor (13) includes a confocal sensor fixture (12). The side-axis confocal sensor (13) is biased and disposed on the side of the laser processing optical path through the confocal sensor fixture (12). The angle between its measuring optical axis and the laser processing optical axis is a set installation angle. The stator of the confocal sensor attitude control motor (11) is fixed relative to the main processing assembly, and the rotor is mechanically connected to the confocal sensor fixture (12). The confocal sensor attitude control motor (11) receives the drive electrical signal and drives the off-axis confocal sensor (13) to rotate around the laser processing optical axis through the rotor.

2. The laser processing head for chemical milling protective adhesive according to claim 1, characterized in that, Also includes: A voice coil motor (8) is provided in the laser processing optical path, and a focusing lens (10) is provided in the laser processing optical path. The fixed end of the voice coil motor (8) is installed on the main processing component, and the movable end is mechanically connected to the lens mount of the focusing lens (10). It receives the input current signal and drives the focusing lens (10) to move linearly along the laser processing optical axis.

3. The laser processing head for chemical milling protective adhesive according to claim 1, characterized in that, Also includes: The imaging module (3) has its optical axis coaxial with or offset fixed on one side of the main processing component, and collects and outputs reflected optical image signals passing through the laser beam action area.

4. A processing system comprising the processing head of claim 3, characterized in that, Also includes: The memory contains preset processing head structure size parameters, confocal sensor bias parameters, thickness conversion model characterizing the numerical mapping relationship between adhesive layer surface distance and metal reference equivalent distance and protective adhesive layer thickness, as well as multi-axis CNC machining programs. The controller (15) includes a microprocessor and a communication interface, and is electrically connected to the A-axis motor (7), the C-axis motor (5), the confocal sensor attitude control motor (11), the capacitive ranging sensor (14), the off-axis confocal sensor (13), and the trigger end of the laser processing optical path, respectively.

5. The processing system according to claim 4, characterized in that, The controller (15) reads the coordinate and angle data fed back by the machine tool axis and executes the multi-axis CNC machining program to determine the coordinate system position of the current laser processing point P1 and the confocal measurement point P2; The controller (15) outputs a drive signal to the confocal sensor attitude control motor (11) to drive the off-axis confocal sensor (13) to rotate to the azimuth angle corresponding to P2; The controller (15) reads the distance signal output by the off-axis confocal sensor (13) as the adhesive surface distance dl and establishes a cache queue in the memory. When the interpolation coordinate reaches the physical position corresponding to P2, the controller extracts the electrical signal of the capacitive distance sensor (14) as the metal reference equivalent distance de. The controller (15) extracts the corresponding dl and the current de from the cache queue, substitutes them into the thickness conversion model to obtain the thickness value result, and generates a control signal with modulation parameters to send to the trigger end of the laser processing optical path.

6. A laser engraving method for chemical milling protective adhesive, using the processing system as described in any one of claims 3-5, characterized in that, Includes the following steps: Step S1: Obtain the structural dimension parameters of the processing head, the attitude transformation relationship between the A-axis and C-axis, the installation angle of the off-axis confocal sensor, the installation offset of the off-axis confocal sensor relative to the laser processing optical axis, and the pre-established thickness conversion model. The thickness conversion model characterizes the numerical mapping relationship between the adhesive layer surface distance, the metal reference equivalent distance, the sensor installation parameters and the protective adhesive layer thickness. Step S2: Obtain the machining trajectory, machining speed, machine tool motion axis position, and current A-axis angle and current C-axis angle; Step S3: Determine the current laser processing point P1 based on the processing head structure size parameters, the current A-axis angle, and the current C-axis angle. P1 is located on the processing trajectory. Step S4: Calculate the confocal sensor attitude control angle based on the feed direction of the machining trajectory, the current A-axis angle, the current C-axis angle, and the mounting offset. Rotate and adjust the off-axis confocal sensor to the confocal sensor attitude control angle so that the corresponding confocal measurement point P2 falls on the machining trajectory in front of P1. Step S5: Calculate the trajectory spacing between P1 and P2 along the machining trajectory. The distance between the adhesive layer surface and the unprocessed area at P2 is obtained using the paraxial confocal sensor. ; Step S6: Based on the trajectory spacing The distance between the adhesive layer surfaces is established based on the processing speed. The spatiotemporal matching relationship between the physical trajectory position and the distance to the adhesive layer surface. Cache; Step S7: When P1 moves to the physical trajectory position corresponding to P2, the equivalent distance of the metal reference at that physical trajectory position is obtained using a capacitive ranging sensor. ; Step S8: Extract the cached data. , will the The above The thickness of the protective adhesive layer at the current position is calculated by substituting the installation angle into the thickness conversion model. ; Step S9: Based on the thickness of the protective adhesive layer The command to generate laser processing parameters is issued to execute laser engraving.

7. The laser engraving method for chemical milling protective adhesive according to claim 6, characterized in that, The off-axis confocal sensor is controlled to rotate around the laser processing optical axis, and the rotation is independent of the transmission path and focusing position of the laser processing optical path.

8. The laser engraving method for chemical milling protective adhesive according to claim 7, characterized in that, The trajectory spacing The arc length distance between P1 and P2 is calculated along the processing trajectory curve; The specific steps for establishing the spatiotemporal matching relationship and caching include: when the processing speed is a constant value. At that time, according to Calculate the The time lead relative to P1 is used as the matching benchmark; When the processing speed is not constant, the real-time speed is integrated or the value is established based on the CNC interpolation cycle. Mapping the coordinates to the physical trajectory and caching them.

9. The laser engraving method for chemical milling protective adhesive according to claim 8, characterized in that, In step S8, the thickness conversion model is specifically as follows: Using calibration function Calculate the thickness of the protective adhesive layer ,in The current A-axis angle, The current C-axis angle, The attitude control angle of the confocal sensor. The installation angle is mentioned above; Alternatively, a linear formula can be used. Calculate the thickness of the protective adhesive layer ,in and These are pre-calibrated coefficients.

10. The laser engraving method for chemical milling protective adhesive according to claim 6, characterized in that, Step S5 also includes: Obtain the normal deviation distance of P2 relative to the machining trajectory. When the normal deviation distance exceeds a preset threshold range, the corresponding position obtained at that location is... Marked as low confidence data.

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