Four-axis linkage laser fine carving machine based on laser path planning

Abstract

The application discloses a four-axis linkage laser fine carving machine based on laser path planning, and relates to the field of laser processing equipment. A first laser processing head, a second laser processing head, a third laser processing head and a fourth laser processing head adopt a unified modular structure, and comprise an optical coupling device, an XY galvanometer scanning module and a dynamic focusing module. The optical coupling device is used for collimating and importing incident laser beams into the XY galvanometer scanning module, and the XY galvanometer scanning module is used for controlling the two-dimensional scanning track of the laser beams in the processing plane. Through the collaborative design of the multi-Z-axis lifting module and the multiple laser processing heads, the application realizes multi-station synchronous processing and greatly improves the processing efficiency. Through the cooperation of the optical coupling device, the XY galvanometer scanning module and the dynamic focusing module, combined with a double-layer focal point compensation structure, the application realizes accurate adjustment of the laser focal point, improves the processing precision of curved surface workpieces, and ensures that the focal point of the light spot always adheres to the processing plane of the workpiece during the processing.

Description

Technical Field

[0001] This invention relates to the field of laser processing equipment technology, and in particular to a four-axis linkage laser engraving machine based on laser path planning. Background Technology

[0002] With the rapid development of the precision manufacturing industry, higher requirements are being placed on the accuracy, efficiency, and multi-station synchronous processing capabilities of workpieces. Traditional laser engraving equipment mostly adopts a single laser processing head structure, which has low processing efficiency and is difficult to meet the needs of batch precision processing; some multi-processing head equipment has problems with unreasonable structural design and poor coordination among processing heads, making it impossible to achieve independent and precise control.

[0003] In the machining of curved workpieces, the positional stability of the laser focus directly affects the machining accuracy. Traditional equipment relies solely on a single Z-axis lifting adjustment to control the focus, resulting in limited adjustment accuracy and slow response speed, making it difficult to adapt to the dynamic machining requirements of curved workpieces. Furthermore, the optical path coupling, scanning, and focusing modules of existing laser processing heads are mostly non-modular designs, leading to cumbersome assembly and debugging, high maintenance costs, and significant beam loss and instability during optical path transmission, further impacting machining quality.

[0004] In addition, the existing laser path planning and the coordinated control of various actuators of the equipment are not precise enough. They cannot adjust the position and focus parameters of each processing head in real time according to the workpiece surface model, which leads to problems such as spot deviation and decreased processing accuracy during the processing, making it difficult to meet the actual needs of high-precision machining. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a four-axis linkage laser engraving machine based on laser path planning. The technical solution is as follows: The four-axis linkage laser engraving machine based on laser path planning consists of a first Z-axis lifting module, a second Z-axis lifting module, a third Z-axis lifting module, and a fourth Z-axis lifting module, which are installed side by side along the X-axis on the gantry frame of the laser engraving machine body. The housings of the first laser processing head, the second laser processing head, the third laser processing head, and the fourth laser processing head are respectively mounted on the sliders of the first Z-axis lifting module, the second Z-axis lifting module, the third Z-axis lifting module, and the fourth Z-axis lifting module; The first, second, third, and fourth laser processing heads adopt a unified modular structure, including an optical path coupling device, an XY galvanometer scanning module, and a dynamic focusing module. The optical path coupling device is used to collimate the incident laser beam and guide it into the XY galvanometer scanning module. The XY galvanometer scanning module is used to control the two-dimensional scanning trajectory of the laser beam in the processing plane. The dynamic focusing module is set on the light-emitting side of the XY galvanometer scanning module and is used to adjust the position of the laser focus along the optical axis in real time during the processing. The laser is connected to the optical input of the optical path coupling device through the beam splitting and beam transmission system; the laser path planning controller is electrically connected to the electric cross slide, the first Z-axis lifting module, the second Z-axis lifting module, the third Z-axis lifting module, the fourth Z-axis lifting module, the first laser processing head, the second laser processing head, the third laser processing head, the fourth laser processing head, the laser, and the beam splitting and beam transmission system of the laser engraving machine body.

[0006] Optionally, the optical path coupling device includes an optical fiber interface flange, a collimating lens barrel, a collimating lens group, a collimating adjustment threaded pair, and a first fixed reflector; The fiber optic interface flange is fixedly installed at the top light inlet of the laser processing head housing, used to connect the fiber optic output end of the beam splitting and beam transmission system; the collimating lens tube is coaxially installed below the fiber optic interface flange; the collimating lens group is movably installed inside the collimating lens tube along the optical axis, and the collimating lens group includes at least two lenses for collimating the diverging laser beam output from the fiber into a parallel beam; the collimating adjustment thread pair is sleeved on the outside of the collimating lens tube and engages with the lens mount thread of the collimating lens group for manually adjusting the axial position of the collimating lens group; the first fixed reflector is fixedly installed at a 45° angle below the light output end of the collimating lens tube, horizontally folding the collimated parallel beam into the XY galvanometer scanning module.

[0007] Optionally, the XY galvanometer scanning module includes a galvanometer housing, an X-axis galvanometer motor, an X-axis reflector, a Y-axis galvanometer motor, a Y-axis reflector, a galvanometer drive board, and an angle encoder; The galvanometer housing is installed inside the laser processing head housing and has a light inlet and a light outlet. The light inlet is aligned with the outgoing light path of the first fixed reflector of the optical path coupling device. The X-axis galvanometer motor is fixedly installed inside the galvanometer housing, and an X-axis reflector is fixed on the output shaft. The Y-axis galvanometer motor is fixedly installed inside the galvanometer housing, with its installation direction perpendicular to that of the X-axis galvanometer motor. A Y-axis reflector is fixed on the output shaft. The galvanometer drive board is integrated inside the side wall of the galvanometer housing, electrically connected to the X-axis galvanometer motor and the Y-axis galvanometer motor, and electrically connected to the laser path planning controller through a digital communication interface; An angle encoder is coaxially set with the rotating shafts of the X-axis galvanometer motor and the Y-axis galvanometer motor, respectively, to detect the deflection angle of the reflector in real time and feed it back to the galvanometer drive board.

[0008] Optionally, the dynamic focusing module includes a focusing lens barrel, a fixed focusing lens, a movable focusing lens, a voice coil motor, a grating ruler displacement sensor, and a protective window. The focusing lens barrel is installed on the light outlet end face of the galvanometer housing of the XY galvanometer scanning module; the fixed focusing lens is installed in the upper part of the focusing lens barrel; The movable focusing lens is slidably mounted inside the focusing lens barrel along the optical axis and is located below the fixed focusing lens; The voice coil motor includes a stator coil and a mover yoke. The stator coil is installed on the inner wall of the focusing lens barrel, and the mover yoke is fixedly connected to the lens mount of the movable focusing lens. The voice coil motor is electrically connected to the laser path planning controller. The scale grating of the grating displacement sensor is mounted on the lens mount of the movable focusing lens, and the reading head is fixed to the inner wall of the focusing lens barrel. It is used to detect the axial displacement of the movable focusing lens in real time and feed it back to the laser path planning controller. The protective window is installed at the bottom of the focusing lens barrel at the light exit. The protective window is made of fused silica material and coated with anti-reflective film on both sides.

[0009] Optionally, the axial adjustment stroke of the movable focusing lens of the dynamic focusing module is ±5mm; the response bandwidth of the voice coil motor is not less than 200Hz; the dynamic focusing module constitutes the focusing axis, and together with the corresponding Z-axis lifting module, they form a double-layer focus compensation structure. The Z-axis lifting module is used for coarse focusing with a large stroke, and the dynamic focusing module is used for fine focusing with a small stroke.

[0010] Optionally, the beam splitting and beam transmission system includes a main beam splitting module, four high-speed optical shutters, four adjustable optical attenuators, and four independent fiber optic transmission channels. The main beam splitter is located at the output port of the laser and splits the incident laser beam into four beams according to a preset ratio. Four high-speed optical shutters are respectively set in the four output optical paths of the main beam splitter module and are electrically connected to the laser path planning controller to independently control the on / off state of the corresponding beam. Four adjustable optical attenuators are respectively set in the optical path after the four high-speed optical shutters and are electrically connected to the laser path planning controller; The fiber optic transmission channel includes a fiber optic coupler, a single-mode transmission fiber, and a fiber optic collimator output head. The fiber optic collimator output head is connected to the fiber optic interface flange of the optical path coupling device of the corresponding laser processing head.

[0011] Optionally, the main beam splitter is a 1-to-4 diffractive optical beam splitter; the high-speed optical shutter is an acousto-optic modulator.

[0012] Optionally, temperature sensors are also integrated inside the housings of the first, second, third, and fourth laser processing heads. The temperature sensors are attached to the outer wall of the galvanometer housing and electrically connected to the laser path planning controller to monitor the working temperature of the laser processing heads in real time.

[0013] Optionally, the electric cross slide is mounted on the platform base of the laser engraving machine body, and the workpiece platform of the laser engraving machine body is mounted on the planar moving part of the electric cross slide for clamping the workpiece to be processed. The laser path planning controller controls the execution action of the electric cross slide.

[0014] Optionally, the laser path planning controller includes a multi-axis motion control card, a galvanometer control card, and a laser control interface. The multi-axis motion control card is electrically connected to the servo motors of the electric cross slide, the first Z-axis lifting module, the second Z-axis lifting module, the third Z-axis lifting module, and the fourth Z-axis lifting module via servo drivers. The galvanometer control card is electrically connected to the galvanometer drive board of each laser processing head via a digital communication protocol. The laser control interface is electrically connected to the modulation port of the laser and the high-speed shutters of the beam splitting and beam transmission system. The laser path planning controller is configured to independently control the height position of each Z-axis lifting module and the focal position of each dynamic focusing module during the processing, based on the surface model of the workpiece and the planned path, so that the spot focus of each laser processing head is always kept on the preset processing plane of the workpiece surface.

[0015] In summary, the present invention has at least one of the following beneficial technical effects: This invention provides a four-axis linkage laser engraving machine based on laser path planning. Through the collaborative design of multiple Z-axis lifting modules and multiple laser processing heads, it can achieve synchronous processing at multiple workstations, greatly improving processing efficiency. The laser processing head adopts a modular structure, which simplifies the assembly and debugging process, reduces maintenance costs, and ensures the consistency of each processing head.

[0016] By combining the optical path coupling device, the XY galvanometer scanning module and the dynamic focusing module, along with the double-layer focus compensation structure, the laser focus can be precisely adjusted, improving the machining accuracy of curved workpieces and ensuring that the laser spot focus always fits the workpiece machining plane during the machining process.

[0017] The precise electrical connection between the laser path planning controller and each actuator enables multi-axis collaborative control, allowing for real-time adjustment of processing parameters based on the workpiece model, thus improving processing stability and consistency. The optimized design of the beam splitting and beam transmission system reduces beam loss, ensuring stable laser energy in each processing head and further enhancing processing quality. Attached Figure Description

[0018] Figure 1This is a three-dimensional structural diagram of the four-axis linkage laser engraving machine based on laser path planning according to the present invention; Figure 2 This is a front view structural schematic diagram of the four-axis linkage laser engraving machine based on laser path planning according to the present invention; Figure 3 This is a side view of the four-axis linkage laser engraving machine based on laser path planning according to the present invention. Figure 4 This is a top view of the four-axis linkage laser engraving machine based on laser path planning according to the present invention. Figure 5 This is a schematic diagram of the laser optical path transmission structure of the four-axis linkage laser engraving machine based on laser path planning according to the present invention; Figure 6 This is a schematic diagram of the combined state structure of the optical path coupling device, XY galvanometer scanning module, and dynamic focusing module of the four-axis linkage laser engraving machine based on laser path planning according to the present invention. Figure 7 This is a schematic diagram of the electrical component connection principle of the four-axis linkage laser engraving machine based on laser path planning according to the present invention.

[0019] Explanation of reference numerals in the attached drawings: 100. Laser engraving machine body; 101. Platform base; 102. Gantry frame; 11. Main beam splitter module; 12. High-speed optical shutter; 13. Adjustable optical attenuator; 14. Fiber optic transmission channel; 21. Workpiece platform; 4. Electric cross slide; 61. First Z-axis lifting module; 62. Second Z-axis lifting module; 63. Third Z-axis lifting module; 64. Fourth Z-axis lifting module; 71. First laser processing head; 72. Second laser processing head; 73. Third laser processing head; 74. Fourth laser processing head; 77. Temperature sensor Sensors; 811, Fiber optic interface flange; 812, Collimating lens barrel; 813, Collimating lens group; 814, Collimating adjustment thread pair; 815, First fixed reflector; 821, Galvanometer housing; 822, X-axis galvanometer motor; 824, Y-axis galvanometer motor; 826, Galvanometer drive board; 827, Angle encoder; 831, Focusing lens barrel; 832, Fixed focusing lens; 833, Movable focusing lens; 834, Voice coil motor; 835, Grating ruler displacement sensor; 836, Protective window plate; 9, Laser; 10, Laser path planning controller. Detailed Implementation

[0020] The present invention will be further described in detail below with reference to the accompanying drawings. See details below. Figures 1-7 .

[0021] This invention discloses a four-axis linkage laser engraving machine based on laser path planning.

[0022] Example 1: A four-axis linkage laser engraving machine based on laser path planning, wherein the first Z-axis lifting module 61, the second Z-axis lifting module 62, the third Z-axis lifting module 63 and the fourth Z-axis lifting module 64 are installed side by side along the X-axis on the gantry frame 102 of the laser engraving machine body 100. The housings of the first laser processing head 71, the second laser processing head 72, the third laser processing head 73, and the fourth laser processing head 74 are respectively mounted on the sliders of the first Z-axis lifting module 61, the second Z-axis lifting module 62, the third Z-axis lifting module 63, and the fourth Z-axis lifting module 64. The first laser processing head 71, the second laser processing head 72, the third laser processing head 73, and the fourth laser processing head 74 adopt a unified modular structure, including an optical path coupling device, an XY galvanometer scanning module, and a dynamic focusing module. The optical path coupling device is used to collimate the incident laser beam and guide it into the XY galvanometer scanning module. The XY galvanometer scanning module is used to control the two-dimensional scanning trajectory of the laser beam in the processing plane. The dynamic focusing module is set on the light-emitting side of the XY galvanometer scanning module and is used to adjust the position of the laser focus along the optical axis in real time during the processing. The laser 9 is connected to the optical path input of the optical path coupling device through the beam splitting and beam transmission system. The laser path planning controller 10 is electrically connected to the electric cross slide 4, the first Z-axis lifting module 61, the second Z-axis lifting module 62, the third Z-axis lifting module 63, the fourth Z-axis lifting module 64, the first laser processing head 71, the second laser processing head 72, the third laser processing head 73, the fourth laser processing head 74, the laser 9, and the beam splitting and beam transmission system of the laser engraving machine body 100.

[0023] By adopting the above technical solution, the first Z-axis lifting module 61, the second Z-axis lifting module 62, the third Z-axis lifting module 63, and the fourth Z-axis lifting module 64 are installed side by side along the X-axis on the gantry frame 102 of the laser engraving machine body 100. The housings of the first laser processing head 71, the second laser processing head 72, the third laser processing head 73, and the fourth laser processing head 74 are respectively fixed on the sliders of each Z-axis lifting module, and rise and fall independently with the sliders to adapt to changes in the workpiece surface height. Each laser processing head adopts a unified modular structure. The laser emitted by the laser 9 is distributed by the beam splitting and beam transmission system and then enters the optical path coupling device. The optical path coupling device collimates the beam and guides it into the XY galvanometer scanning module. The XY galvanometer scanning module controls the laser beam to scan at high speed in the processing plane, and the dynamic focusing module adjusts the axial position of the focal point in real time on the light-emitting side. The laser path planning controller 10 controls the electric cross slide 4 to move the workpiece in a plane according to the planned path. At the same time, it controls the independent lifting of the four Z-axis lifting modules and the coordinated work of the four laser processing heads to complete the four-axis linkage laser engraving.

[0024] Example 2: The optical path coupling device includes an optical fiber interface flange 811, a collimating lens barrel 812, a collimating lens group 813, a collimating adjustment threaded pair 814, and a first fixed reflector 815. The fiber optic interface flange 811 is fixedly installed at the top light inlet of the laser processing head housing for connecting the fiber optic output end of the beam splitting and beam transmission system; the collimating lens barrel 812 is coaxially installed below the fiber optic interface flange 811; the collimating lens group 813 is movably installed inside the collimating lens barrel 812 along the optical axis, and the collimating lens group 813 includes at least two lenses for collimating the diverging laser beam output from the fiber into a parallel beam; the collimating adjustment threaded pair 814 is sleeved on the outside of the collimating lens barrel 812 and engages with the lens mount thread of the collimating lens group 813 for manually adjusting the axial position of the collimating lens group; the first fixed reflector 815 is fixedly installed at a 45° angle below the light output end of the collimating lens barrel 812 to horizontally fold the collimated parallel beam into the XY galvanometer scanning module.

[0025] By adopting the above technical solution, the optical path coupling device is connected to the optical fiber output end of the beam splitting and beam transmission system through the optical fiber interface flange 811. After the laser beam enters the collimating lens tube 812, the collimating lens group 813 collimates the diverging beam into a parallel beam. The collimation adjustment thread pair 814 can manually adjust the axial position of the collimating lens group 813 to compensate for optical path deviation. The collimated parallel beam is deflected at a 45° angle by the first fixed reflector 815 and enters the XY galvanometer scanning module horizontally, providing high-quality parallel incident light for subsequent galvanometer scanning.

[0026] Example 3: The XY galvanometer scanning module includes a galvanometer housing 821, an X-axis galvanometer motor 822, an X-axis reflector, a Y-axis galvanometer motor 824, a Y-axis reflector, a galvanometer drive board 826, and an angle encoder 827. The galvanometer housing 821 is installed inside the laser processing head housing and has a light inlet and a light outlet. The light inlet is aligned with the outgoing light path of the first fixed reflector 815 of the optical path coupling device. The X-axis galvanometer motor 822 is fixedly installed inside the galvanometer housing 821, and an X-axis reflector is fixed on the output shaft; The Y-axis galvanometer motor 824 is fixedly installed inside the galvanometer housing 821, with its installation direction perpendicular to that of the X-axis galvanometer motor 822. A Y-axis reflector is fixed on the output shaft. The galvanometer drive board 826 is integrated in the side wall of the galvanometer housing 821, and is electrically connected to the X-axis galvanometer motor 822 and the Y-axis galvanometer motor 824, and is electrically connected to the laser path planning controller 10 through a digital communication interface; Angle encoder 827 is coaxially set with the rotating shafts of X-axis galvanometer motor 822 and Y-axis galvanometer motor 824, respectively, and is used to detect the deflection angle of the reflector in real time and feed it back to the galvanometer drive board 826.

[0027] By adopting the above technical solution, within the galvanometer housing 821 of the XY galvanometer scanning module, the X-axis galvanometer motor 822 drives the X-axis reflector to deflect, and the Y-axis galvanometer motor 824 drives the Y-axis reflector to deflect. The two reflectors cooperate in the vertical direction to change the emission angle of the laser beam, thereby achieving two-dimensional scanning trajectory control within the processing plane. The galvanometer drive board 826 receives instructions from the laser path planning controller 10 and drives the two motors to move. The angle encoder 827 detects the reflector deflection angle in real time and feeds it back to the galvanometer drive board 826 to form a closed-loop control, ensuring the accuracy of the scanning position.

[0028] Example 4: The dynamic focusing module includes a focusing lens barrel 831, a fixed focusing lens 832, a movable focusing lens 833, a voice coil motor 834, a grating ruler displacement sensor 835, and a protective window 836. The focusing lens barrel 831 is installed on the light outlet end face of the galvanometer housing 821 of the XY galvanometer scanning module; the fixed focusing lens 832 is installed in the upper part of the focusing lens barrel 831; The movable focusing lens 833 is slidably mounted inside the focusing lens barrel 831 along the optical axis and is located below the fixed focusing lens 832; The voice coil motor 834 includes a stator coil and a mover yoke. The stator coil is installed on the inner wall of the focusing lens barrel 831, and the mover yoke is fixedly connected to the lens mount of the movable focusing lens 833. The voice coil motor 834 is electrically connected to the laser path planning controller 10. The scale grating of the grating displacement sensor 835 is mounted on the lens mount of the movable focusing lens 833, and the reading head is fixed to the inner wall of the focusing lens barrel 831. It is used to detect the axial displacement of the movable focusing lens in real time and feed it back to the laser path planning controller 10. The protective window 836 is installed at the bottom light outlet of the focusing lens barrel 831. The protective window 836 is made of fused silica material and coated with anti-reflective film on both sides.

[0029] By adopting the above technical solution, the focusing lens barrel 831 of the dynamic focusing module is installed at the light outlet of the galvanometer housing 821. The fixed focusing lens 832 and the movable focusing lens 833 form a zoom optical system. The voice coil motor 834 receives the control signal from the laser path planning controller 10 and drives the movable focusing lens 833 to move along the optical axis, changing the lens group spacing and thus adjusting the axial position of the laser focus. The grating ruler displacement sensor 835 detects the displacement of the movable focusing lens 833 in real time and feeds it back to the laser path planning controller 10 to achieve closed-loop control. The protective window 836 prevents processing dust from contaminating the internal optical components.

[0030] In Example 5, the axial adjustment stroke of the movable focusing lens 833 of the dynamic focusing module is ±5mm; the response bandwidth of the voice coil motor 834 is not less than 200Hz; the dynamic focusing module constitutes the focusing axis, and together with the corresponding Z-axis lifting module, they form a double-layer focus compensation structure. The Z-axis lifting module is used for coarse focusing with a large stroke, and the dynamic focusing module is used for fine focusing with a small stroke.

[0031] By adopting the above technical solution, the axial adjustment stroke of the movable focusing lens 833 is set to ±5mm, which meets the focus compensation requirements of conventional curved surface processing. The voice coil motor 834 has a response bandwidth of not less than 200Hz, enabling it to quickly follow the focus adjustment commands issued by the laser path planning controller 10. The dynamic focusing module, as the focusing axis, forms a double-layer focus compensation structure with the corresponding Z-axis lifting module. The Z-axis lifting module is responsible for the initial focusing with a large stroke and coarse following of the workpiece contour, while the dynamic focusing module is responsible for high-frequency, small-amplitude fine-tuning of the focus during processing, ensuring that the focal spot accurately falls on the workpiece surface throughout the curved surface processing.

[0032] Example 6: The beam splitting and beam transmission system includes a main beam splitting module 11, four high-speed optical shutters 12, four adjustable optical attenuators 13, and four independent optical fiber transmission channels 14. The main beam splitting module 11 is located at the output port of the laser 9 and splits the incident laser beam into four beams according to a preset ratio. Four high-speed optical shutters 12 are respectively set in the four output optical paths of the main beam splitter module and are electrically connected to the laser path planning controller 10 to independently control the on / off state of the corresponding beam. Four adjustable optical attenuators 13 are respectively disposed in the optical path after the four high-speed optical shutters 12 and are electrically connected to the laser path planning controller 10; The optical fiber transmission channel 14 includes an optical fiber coupler, a single-mode transmission fiber, and an optical fiber collimation output head. The optical fiber collimation output head is connected to the optical fiber interface flange 811 of the optical path coupling device of the corresponding laser processing head.

[0033] By adopting the above technical solution, in the beam splitting and beam transmission system, the main beam splitting module 11 splits the single laser beam output from the laser 9 into four beams according to a preset ratio. The four laser beams pass through four high-speed optical shutters 12, which independently control the on / off state of each optical path under the control of the laser path planning controller 10. The beams passing through the high-speed optical shutters 12 then undergo fine power adjustment via four adjustable optical attenuators 13. Four independent fiber optic transmission channels 14 transmit each beam to the fiber optic interface flanges 811 of the optical path coupling devices of the four laser processing heads, achieving independent and controllable supply of the four beams.

[0034] In Example 7, the main beam splitter module 11 is a diffractive optical beam splitter that splits a beam into four; the high-speed optical shutter 12 is an acousto-optic modulator.

[0035] By adopting the above technical solution, the main beam splitting module 11 uses a 1-to-4 diffractive optical beam splitter, which utilizes surface micro-nano structures to efficiently split the incident laser beam. The high-speed optical shutter 12 uses an acousto-optic modulator, which controls the deflection of diffracted light in the acousto-optic medium through radio frequency signals to achieve rapid switching of the optical path, and the response speed meets the beam switching requirements of high-speed processing.

[0036] In Example 8, a temperature sensor 77 is also integrated inside the housing of the first laser processing head 71, the second laser processing head 72, the third laser processing head 73, and the fourth laser processing head 74. The temperature sensor 77 is attached to the outer wall of the galvanometer housing 821 and electrically connected to the laser path planning controller 10 for real-time monitoring of the working temperature of the laser processing head.

[0037] By adopting the above technical solution, the temperature sensor 77 is attached to the outer wall of the galvanometer housing 821 to detect the temperature change of the laser processing head in real time. The temperature sensor 77 transmits the temperature signal to the laser path planning controller 10, which can monitor the working status of the galvanometer motor and take protective measures or perform thermal drift compensation when the temperature is abnormal, so as to ensure the stability of long-term processing.

[0038] In Example 9, the electric cross slide 4 is mounted on the platform base 101 of the laser engraving machine body 100, and the workpiece platform 21 of the laser engraving machine body 100 is mounted on the planar moving part of the electric cross slide 4 for clamping the workpiece to be processed. The laser path planning controller 10 controls the execution action of the electric cross slide 4.

[0039] By adopting the above technical solution, the electric cross slide 4 is installed on the platform base 101 of the laser engraving machine body 100, and the workpiece platform 21 is fixed to the planar moving part of the electric cross slide 4. The workpiece to be processed, clamped on the workpiece platform 21, moves along the X and Y directions in the horizontal plane with the electric cross slide 4. The laser path planning controller 10 controls the servo motor of the electric cross slide 4 to perform actions, so that the relatively fixed laser processing head group of the workpiece can realize planar position changes, which together with the vertical movement of the Z-axis lifting module and the galvanometer scanning constitute a four-axis linkage processing capability.

[0040] Example 10: The laser path planning controller 10 includes a multi-axis motion control card, a galvanometer control card, and a laser control interface. The multi-axis motion control card is electrically connected to the servo motors of the electric cross slide 4, the first Z-axis lifting module 61, the second Z-axis lifting module 62, the third Z-axis lifting module 63, and the fourth Z-axis lifting module 64 via servo drivers. The galvanometer control card is electrically connected to the galvanometer drive board 826 of each laser processing head via a digital communication protocol. The laser control interface is electrically connected to the modulation port of the laser 9 and the high-speed shutters 12 of the beam splitting and beam transmission system. The laser path planning controller 10 is configured to independently control the height position of each Z-axis lifting module and the focal position of each dynamic focusing module during the processing according to the surface model of the workpiece to be processed and the planned path, so that the spot focus of each laser processing head is always kept on the preset processing plane on the workpiece surface.

[0041] By adopting the above technical solution, the multi-axis motion control card of the laser path planning controller 10 controls the servo motors of the electric cross slide 4, the first Z-axis lifting module 61, the second Z-axis lifting module 62, the third Z-axis lifting module 63, and the fourth Z-axis lifting module 64 through servo drivers, realizing the planar motion of the workpiece and the independent lifting motion of the four laser heads. The galvanometer control card sends scanning commands to each galvanometer driver board 826 through a digital communication protocol. The laser control interface controls the power modulation of the laser 9 and the on / off state of each high-speed optical shutter 12. According to the workpiece surface model and the planned path, the laser path planning controller 10 synchronously adjusts the height of each Z-axis lifting module and the focal position of each dynamic focusing module during the processing, ensuring that the laser spot focus of the four laser processing heads is always maintained on the preset processing plane on the workpiece surface, realizing high-precision four-axis linkage laser engraving.

[0042] The following specific embodiments illustrate the implementation principle of the present invention: taking the etching of curved surfaces of precision electronic components as an application scenario, it achieves four-station synchronous high-precision laser engraving. The specific implementation process is as follows: First, assemble the equipment. Install the electric cross slide 4 on the platform base 101 of the laser engraving machine body 100. Install the workpiece platform 21 of the laser engraving machine body 100 on the planar moving part of the electric cross slide 4. The workpiece platform 21 is used to clamp four identical curved electronic components to be processed. Install the first Z-axis lifting module 61, the second Z-axis lifting module 62, the third Z-axis lifting module 63, and the fourth Z-axis lifting module 64 in a parallel arrangement along the X-axis on the gantry frame 102 of the laser engraving machine body 100. Then, install the housings of the first laser processing head 71, the second laser processing head 72, the third laser processing head 73, and the fourth laser processing head 74 on the sliders of the first Z-axis lifting module 61, the second Z-axis lifting module 62, the third Z-axis lifting module 63, and the fourth Z-axis lifting module 64, respectively, ensuring that each laser processing head is directly facing the workpiece to be processed on the workpiece platform 21.

[0043] Each laser processing head adopts a unified modular structure and is equipped with an optical path coupling device, an XY galvanometer scanning module, and a dynamic focusing module. The assembly of the optical path coupling device follows these specifications: the fiber optic interface flange 811 is fixedly installed at the top light inlet of the laser processing head housing; the collimating lens tube 812 is coaxially installed below the fiber optic interface flange 811; the collimating lens group 813, consisting of at least two lenses, is movably installed inside the collimating lens tube 812 along the optical axis; the collimation adjustment threaded pair 814 is sleeved on the outside of the collimating lens tube 812 and threadedly engaged with the lens mount of the collimating lens group 813; and the first fixed reflector 815 is fixedly installed at a 45° angle below the light-emitting end of the collimating lens tube 812 to ensure that its emitted light path is aligned with the light inlet of the XY galvanometer scanning module.

[0044] The assembly process of the XY galvanometer scanning module is as follows: The galvanometer housing 821 is installed inside the laser processing head housing, aligning its light inlet with the output light path of the first fixed reflector 815 of the optical path coupling device; the X-axis galvanometer motor 822 is fixedly installed inside the galvanometer housing 821, and an X-axis reflector is fixed on its output shaft; the Y-axis galvanometer motor 824 is fixedly installed inside the galvanometer housing 821, with its installation direction perpendicular to the installation direction of the X-axis galvanometer motor 822, and a Y-axis reflector is fixed on its output shaft; the galvanometer drive board 826 is integrated into the side wall of the galvanometer housing 821 and electrically connected to the X-axis galvanometer motor 822 and the Y-axis galvanometer motor 824 respectively; the angle encoder 827 is coaxially set with the rotating shafts of the X-axis galvanometer motor 822 and the Y-axis galvanometer motor 824 respectively, ensuring that the deflection angle of the reflector can be detected in real time and fed back to the galvanometer drive board 826.

[0045] The dynamic focusing module is assembled as follows: The focusing lens barrel 831 is installed on the light-emitting end face of the galvanometer housing 821 of the XY galvanometer scanning module; the fixed focusing lens 832 is installed in the upper part of the focusing lens barrel 831; the movable focusing lens 833 is slidably installed in the focusing lens barrel 831 along the optical axis and located below the fixed focusing lens 832; the stator coil of the voice coil motor 834 is installed on the inner wall of the focusing lens barrel 831, and the moving magnetic yoke is fixedly connected to the lens mount of the movable focusing lens 833; the scale grating of the grating displacement sensor 835 is installed on the lens mount of the movable focusing lens 833, and the reading head is fixed to the inner wall of the focusing lens barrel 831; a protective window 836 made of fused silica material and coated with anti-reflection film on both sides is installed at the bottom light-emitting port of the focusing lens barrel 831. Among them, the axial adjustment stroke of the movable focusing lens 833 is set to ±5mm, the response bandwidth of the voice coil motor 834 is not less than 200Hz, the dynamic focusing module constitutes the focusing axis, and together with the corresponding Z-axis lifting module, they form a double-layer focus compensation structure. The Z-axis lifting module is used for coarse focusing with a large stroke, and the dynamic focusing module is used for fine focusing with a small stroke.

[0046] The assembly process of the beam splitting and beam transmission system is as follows: The main beam splitting module 11 is set at the output port of the laser 9. The main beam splitting module 11 adopts a 1-to-4 diffractive optical beam splitter to split the incident laser beam into four output beams according to a preset ratio. Four high-speed optical shutters 12 are respectively set in the four output optical paths of the main beam splitting module. The high-speed optical shutters 12 adopt acousto-optic modulators and are electrically connected to the laser path planning controller 10. Four adjustable optical attenuators 13 are respectively set in the optical paths after the four high-speed optical shutters 12 and are electrically connected to the laser path planning controller 10. Four independent optical fiber transmission channels 14 correspond to the four optical paths. Each optical fiber transmission channel 14 includes an optical fiber coupler, a single-mode transmission fiber, and an optical fiber collimation output head. The optical fiber collimation output head is connected to the optical fiber interface flange 811 of the optical path coupling device of the corresponding laser processing head to realize the optical path connection between the laser 9 and each laser processing head.

[0047] Temperature sensors 77 are integrated within the housings of each laser processing head and attached to the outer wall of the galvanometer housing 821, electrically connected to the laser path planning controller 10, for real-time monitoring of the working temperature of the laser processing head. The laser path planning controller 10 includes a multi-axis motion control card, a galvanometer control card, and a laser control interface. The multi-axis motion control card is electrically connected to the servo motors of the electric cross slide 4, the first Z-axis lifting module 61, the second Z-axis lifting module 62, the third Z-axis lifting module 63, and the fourth Z-axis lifting module 64 via servo drivers. The galvanometer control card is electrically connected to the galvanometer drive board 826 of each laser processing head via a digital communication protocol. The laser control interface is electrically connected to the modulation port of the laser 9 and the high-speed shutters 12 of the beam splitting and beam transmission system.

[0048] After the equipment is started, the electronic components to be processed are clamped on the four stations of the workpiece platform 21. The laser path planning controller 10 imports the surface model and planned path of the workpiece to be processed and starts the processing flow. The laser 9 emits a laser beam, which is split into four beams by the main beam splitting module 11 according to a preset ratio. The four laser beams pass through four high-speed optical shutters 12 respectively. The laser path planning controller 10 controls the high-speed optical shutters 12 to open, so that the laser beams enter the adjustable optical attenuator 13. After being adjusted to the preset power by the adjustable optical attenuator 13, they are transmitted through the optical fiber transmission channel 14 to the optical fiber interface flange 811 of the optical path coupling device of each laser processing head.

[0049] After the laser beam enters the optical path coupling device, the collimating lens group 813 collimates the diverging laser beam output from the optical fiber into a parallel beam. The axial position of the collimating lens group 813 is adjusted by rotating the collimating adjustment screw pair 814 to compensate for optical path deviation. The collimated parallel beam is then horizontally deflected at a 45° angle by the first fixed reflector 815 and enters the XY galvanometer scanning module. The galvanometer drive board 826 of the XY galvanometer scanning module receives instructions from the laser path planning controller 10 and drives the X-axis galvanometer motor 822 and the Y-axis galvanometer motor 824 to rotate, causing the X-axis and Y-axis reflectors to deflect. The two reflectors work together to change the exit angle of the laser beam, realizing two-dimensional scanning trajectory control within the processing plane. The angle encoder 827 detects the deflection angle of the reflectors in real time and feeds it back to the galvanometer drive board 826, forming a closed-loop control to ensure accurate scanning position.

[0050] After exiting the XY galvanometer scanning module, the laser beam enters the dynamic focusing module. The fixed focusing lens 832 and the movable focusing lens 833 form a zoom optical system. The laser path planning controller 10 sends a control signal to the voice coil motor 834, driving the movable focusing lens 833 to move along the optical axis, changing the lens group spacing, thereby adjusting the position of the laser focus along the optical axis in real time. The grating ruler displacement sensor 835 detects the axial displacement of the movable focusing lens 833 in real time and feeds it back to the laser path planning controller 10, forming a closed-loop control to ensure precise focus adjustment. At the same time, the laser path planning controller 10 controls the independent lifting of the first Z-axis lifting module 61, the second Z-axis lifting module 62, the third Z-axis lifting module 63, and the fourth Z-axis lifting module 64 to achieve large-stroke coarse focusing, which, together with the small-stroke fine focusing of the dynamic focusing module, forms a double-layer focus compensation structure to ensure that the laser focus is always in contact with the curved surface of the workpiece.

[0051] During processing, the laser path planning controller 10 controls the movement of the electric cross slide 4, driving the workpiece platform 21 and the workpiece to be processed to move along the X and Y directions in the horizontal plane. This works in conjunction with the vertical movement of each Z-axis lifting module, the galvanometer scanning of each laser processing head, and dynamic focusing, achieving four-axis linkage laser engraving. The temperature sensor 77 monitors the working temperature of the laser processing head in real time and transmits the temperature signal to the laser path planning controller 10. The controller monitors the working status of the galvanometer motor in real time, taking timely protective measures and performing thermal drift compensation when the temperature is abnormal, ensuring processing stability. The four laser processing heads work synchronously, etching the four workpieces on the workpiece platform 21 respectively. The high-speed optical shutter 12 can independently control the on / off state of the corresponding beam according to processing requirements, and the adjustable attenuator 13 adjusts the power of each beam in real time to ensure consistent processing quality for the four workpieces.

[0052] After processing is completed, the laser path planning controller 10 controls the laser 9 to stop emitting light, the high-speed optical shutter 12 closes, each Z-axis lifting module resets, and the electric cross slide 4 drives the workpiece platform 21 to the material picking position, completing the entire four-axis linkage laser precision engraving process.

[0053] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A four-axis linkage laser engraving machine based on laser path planning, characterized in that, The first Z-axis lifting module (61), the second Z-axis lifting module (62), the third Z-axis lifting module (63) and the fourth Z-axis lifting module (64) are installed side by side along the X-axis on the gantry frame (102) of the laser engraving machine body (100); The housings of the first laser processing head (71), the second laser processing head (72), the third laser processing head (73), and the fourth laser processing head (74) are respectively mounted on the sliders of the first Z-axis lifting module (61), the second Z-axis lifting module (62), the third Z-axis lifting module (63), and the fourth Z-axis lifting module (64); The first laser processing head (71), the second laser processing head (72), the third laser processing head (73), and the fourth laser processing head (74) adopt a unified modular structure, including an optical path coupling device, an XY galvanometer scanning module, and a dynamic focusing module. The optical path coupling device is used to collimate the incident laser beam and guide it into the XY galvanometer scanning module. The XY galvanometer scanning module is used to control the two-dimensional scanning trajectory of the laser beam in the processing plane. The dynamic focusing module is set on the light-emitting side of the XY galvanometer scanning module and is used to adjust the position of the laser focus along the optical axis in real time during the processing. The laser (9) is connected to the optical path input terminal of the optical path coupling device through the beam splitting and beam transmission system; the laser path planning controller (10) is electrically connected to the electric cross slide (4), the first Z-axis lifting module (61), the second Z-axis lifting module (62), the third Z-axis lifting module (63), the fourth Z-axis lifting module (64), the first laser processing head (71), the second laser processing head (72), the third laser processing head (73), the fourth laser processing head (74), the laser (9), and the beam splitting and beam transmission system of the laser engraving machine body (100); The laser path planning controller (10) independently controls the height position of each Z-axis lifting module and the focal position of each dynamic focusing module during the processing, so that the laser spot focus of each laser processing head is always kept on the preset processing plane on the workpiece surface.

2. The four-axis linkage laser engraving machine based on laser path planning according to claim 1, characterized in that, The optical path coupling device includes an optical fiber interface flange (811), a collimating lens barrel (812), a collimating lens group (813), a collimating adjustment thread pair (814), and a first fixed reflector (815). The fiber optic interface flange (811) is fixedly installed at the top light inlet of the laser processing head housing for connecting the fiber optic output end of the beam splitting and beam transmission system; the collimating lens tube (812) is coaxially installed below the fiber optic interface flange (811); the collimating lens group (813) is movably installed inside the collimating lens tube (812) along the optical axis direction, and the collimating lens group (813) includes at least two lenses for collimating the diverging laser beam output from the fiber into a parallel beam; the collimating adjustment thread pair (814) is sleeved on the outside of the collimating lens tube (812) and engages with the lens mount thread of the collimating lens group (813) for manually adjusting the axial position of the collimating lens group; the first fixed reflector (815) is fixedly installed at a 45° angle below the light output end of the collimating lens tube (812) to horizontally fold the collimated parallel beam into the XY galvanometer scanning module.

3. The four-axis linkage laser engraving machine based on laser path planning according to claim 2, characterized in that, The XY galvanometer scanning module includes a galvanometer housing (821), an X-axis galvanometer motor (822), an X-axis reflector, a Y-axis galvanometer motor (824), a Y-axis reflector, a galvanometer drive board (826), and an angle encoder (827). The galvanometer housing (821) is installed inside the laser processing head housing and has an inlet and an outlet. The inlet is aligned with the outgoing light path of the first fixed mirror (815) of the optical path coupling device. The X-axis galvanometer motor (822) is fixedly installed inside the galvanometer housing (821), and an X-axis reflector is fixed on the output shaft; The Y-axis galvanometer motor (824) is fixedly installed inside the galvanometer housing (821), with its installation direction perpendicular to that of the X-axis galvanometer motor (822). A Y-axis reflector is fixed on the output shaft. The galvanometer drive board (826) is integrated in the side wall of the galvanometer housing (821), electrically connected to the X-axis galvanometer motor (822) and the Y-axis galvanometer motor (824), and electrically connected to the laser path planning controller (10) through a digital communication interface; An angle encoder (827) is coaxially set with the rotating shafts of the X-axis galvanometer motor (822) and the Y-axis galvanometer motor (824) respectively, and is used to detect the deflection angle of the reflector in real time and feed it back to the galvanometer drive board (826).

4. The four-axis linkage laser engraving machine based on laser path planning according to claim 3, characterized in that, The dynamic focusing module includes a focusing lens barrel (831), a fixed focusing lens (832), a movable focusing lens (833), a voice coil motor (834), a grating ruler displacement sensor (835), and a protective window (836). The focusing lens barrel (831) is installed on the light outlet end face of the galvanometer housing (821) of the XY galvanometer scanning module; the fixed focusing lens (832) is installed in the upper part of the focusing lens barrel (831); The movable focusing lens (833) is slidably mounted inside the focusing lens barrel (831) along the optical axis and is located below the fixed focusing lens (832); The voice coil motor (834) includes a stator coil and a mover yoke. The stator coil is installed on the inner wall of the focusing lens barrel (831), and the mover yoke is fixedly connected to the lens mount of the movable focusing lens (833). The voice coil motor (834) is electrically connected to the laser path planning controller (10). The scale grating of the grating displacement sensor (835) is mounted on the lens mount of the movable focusing lens (833), and the reading head is fixed to the inner wall of the focusing lens barrel (831) for real-time detection of the axial displacement of the movable focusing lens and feedback to the laser path planning controller (10). The protective window (836) is installed at the bottom light outlet of the focusing lens barrel (831). The protective window (836) is made of fused silica material and coated with anti-reflection film on both sides.

5. The four-axis linkage laser engraving machine based on laser path planning according to claim 4, characterized in that, The axial adjustment stroke of the movable focusing lens (833) of the dynamic focusing module is ±5mm; the response bandwidth of the voice coil motor (834) is not less than 200Hz; the dynamic focusing module constitutes the focusing axis, and together with the corresponding Z-axis lifting module, they form a double-layer focus compensation structure. The Z-axis lifting module is used for coarse focusing with a large stroke, and the dynamic focusing module is used for fine focusing with a small stroke.

6. The four-axis linkage laser engraving machine based on laser path planning according to claim 5, characterized in that, The beam splitting and beam transmission system includes a main beam splitting module (11), four high-speed optical shutters (12), four adjustable optical attenuators (13), and four independent optical fiber transmission channels (14). The main beam splitting module (11) is located at the output port of the laser (9) and splits the incident laser beam into four beams according to a preset ratio. Four high-speed optical shutters (12) are respectively set in the four output optical paths of the main beam splitter module and are electrically connected to the laser path planning controller (10) to independently control the on / off state of the corresponding beams; Four adjustable optical attenuators (13) are respectively set in the optical path after the four high-speed optical shutters (12) and electrically connected to the laser path planning controller (10); The optical fiber transmission channel (14) includes an optical fiber coupler, a single-mode transmission fiber and an optical fiber collimation output head. The optical fiber collimation output head is connected to the optical fiber interface flange (811) of the optical path coupling device of the corresponding laser processing head.

7. The four-axis linkage laser engraving machine based on laser path planning according to claim 6, characterized in that, The main beam splitter (11) is a diffractive optical beam splitter that splits a beam into four; the high-speed optical shutter (12) is an acousto-optic modulator.

8. The four-axis linkage laser engraving machine based on laser path planning according to claim 7, characterized in that, Temperature sensors (77) are also integrated inside the housings of the first laser processing head (71), the second laser processing head (72), the third laser processing head (73), and the fourth laser processing head (74). The temperature sensors (77) are attached to the outer wall of the galvanometer housing (821) and electrically connected to the laser path planning controller (10) for real-time monitoring of the working temperature of the laser processing head.

9. The four-axis linkage laser engraving machine based on laser path planning according to claim 8, characterized in that, The electric cross slide (4) is installed on the platform base (101) of the laser engraving machine body (100). The workpiece platform (21) of the laser engraving machine body (100) is installed on the planar moving part of the electric cross slide (4) for clamping the workpiece to be processed. The laser path planning controller (10) controls the execution action of the electric cross slide (4).

10. The four-axis linkage laser engraving machine based on laser path planning according to claim 9, characterized in that, The laser path planning controller (10) includes a multi-axis motion control card, a galvanometer control card, and a laser control interface. The multi-axis motion control card is electrically connected to the servo motors of the electric cross slide (4), the first Z-axis lifting module (61), the second Z-axis lifting module (62), the third Z-axis lifting module (63), and the fourth Z-axis lifting module (64) via servo drivers. The galvanometer control card is electrically connected to the galvanometer drive board (826) of each laser processing head via a digital communication protocol. The laser control interface is electrically connected to the modulation port of the laser (9) and the high-speed shutters (12) of the beam splitting and beam transmission system. The laser path planning controller (10) is configured to independently control the height position of each Z-axis lifting module and the focal position of each dynamic focusing module during the processing according to the surface model of the workpiece to be processed and the planned path, so that the spot focus of each laser processing head is always kept on the preset processing plane on the workpiece surface.

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