Automatic laser marking machine and laser marking method thereof

Abstract

The invention discloses an automatic laser marking machine and a laser marking method thereof, and relates to the technical field of laser processing and automatic control, and the automatic laser marking machine comprises a laser marking device, a reference detection device, a rotatable part bracket with a plurality of tool seats, a bracket driving device, a state acquisition device and a controller. And the controller establishes a tool seat occupation state through state acquisition, shields a no-load tool seat, establishes a process load value, a mechanical constraint value and a cross-process retention value in combination with the extracted plane deviation and angular deviation, and generates a boundary modulation value for updating a state machine boundary. During marking, the rotatable part support bears angular compensation, the angular acceleration in the transposition process is restrained according to the additional eccentric radius, and plane compensation is executed by the galvanometer scanning assembly. According to the scheme, the secondary slippage risk is reduced, the marked parts are kept in the original tool state to enter the paint spraying procedure, and the positioning precision and the procedure cooperation efficiency of multi-station continuous machining are improved.

Description

Technical Field

[0001] This invention relates to the field of laser processing and automation control technology, and more specifically, to an automated laser marking machine and its laser marking method. Background Technology

[0002] Laser marking equipment is widely used in the processing of identification codes, characters, patterns, and process markings on products such as hardware, electronic structural components, plastic parts, and assemblies. With the development of flexible manufacturing and automated production, the production site not only requires accurate marking positions and stable processing cycles, but also demands that the equipment can adapt to different part postures, different marking patterns, and multi-station continuous processing needs, while minimizing manual handling of individual parts and repetitive alignment operations.

[0003] In the prior art, CN106964904B discloses a method that integrates machine vision positioning, laser galvanometer scanning optical path, Z-axis automatic focusing lifting stage, and... This laser marking equipment combines a multi-angle rotating worktable with product positioning learning and subsequent automatic adjustment to achieve automated laser marking on multiple working surfaces of a single product.

[0004] The core components and process of this solution can be summarized as follows: The product to be processed is mounted in a fixed fixture on the rotary table module; visual features of the product surface are captured using an industrial camera; and then, combined with red light preview, Z-axis autofocus, and... Angle adjustment is performed to learn the positioning of the workpiece and generate a processing document. During subsequent processing, the Z-axis coordinates of the product are adjusted based on the visual positioning information in the processing document. The laser marking is then completed by the laser and galvanometer assembly. In other words, this solution already possesses common technical features similar to the preceding part of this case, such as laser marking device, visual positioning, rotating worktable, and automatic marking after posture adjustment.

[0005] However, in application scenarios involving the simultaneous handling of multiple parts, switching between mixed pattern tasks, and seamless integration with subsequent painting processes, the aforementioned solution still primarily focuses on the visual learning and angle switching of multiple working surfaces of a single product. Its rotating worktable essentially still serves the multi-faceted processing of a single product. Furthermore, the processing flow described in its manual still includes manual loading and unloading, and sequential execution according to the processing document. Therefore, in scenarios requiring parallel loading of multiple parts, the presence of idle workstations, inconsistent initial placement deviations of parts, and the requirement to maintain the tooling posture after marking before proceeding to the next process, problems such as idle workstations, difficulty in balancing rotation and stability, and insufficient tooling flow coordination can still easily arise.

[0006] Therefore, it is still necessary to provide an automated laser marking machine and its laser marking method to further improve multi-station continuous processing capability, reduce manual intervention, improve the adaptability of part support rotation control, and enhance tooling connection efficiency with subsequent painting processes while maintaining laser marking accuracy. Summary of the Invention

[0007] In order to overcome the above-mentioned defects of the prior art, the embodiments of the present invention provide an automated laser marking machine and its laser marking method. By setting up a rotatable part support and combining reference detection, status acquisition and boundary modulation control, the continuous automatic marking of multiple parts can be realized, so as to solve the problems of low efficiency of manual one-by-one picking and placing, poor marking consistency and insufficient tooling cross-process flow capability mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: An automated laser marking machine includes a frame, a laser marking device, a reference detection device, a rotatable part support, a support drive device, a status acquisition device, and a controller. The laser marking device is disposed on the upper part of the frame, and the rotatable part support is disposed below the laser marking device. The rotatable part support includes a central rotating shaft, a support plate, and multiple tooling seats. The support plate is mounted on the central rotating shaft, and the multiple tooling seats are spaced apart circumferentially along the support plate. Each tooling seat is used to support a part to be marked. The reference detection device is used to detect reference features of the part and the tooling seats. The support drive device is used to drive the rotatable part support to rotate. The status acquisition device is used to acquire the status of the tooling and the operating status of the support. The controller is connected to the laser marking device and the reference detection device. The device, support drive device, and state acquisition device are connected. The controller is used to: establish the occupancy status of each tooling seat; extract part reference features and tooling reference features for candidate tooling seats, and establish the planar deviation and angular deviation of the current part relative to the tooling seat; establish process load value, mechanical constraint value, and cross-process retention value according to the planar deviation, angular deviation, support running status, and the requirements of the painting process for posture maintenance, tooling docking direction, and flow sequence, and generate boundary modulation value; update the state machine boundary according to the boundary modulation value and control the rotation of the rotatable part support; when the marking conditions are met, control the laser marking device to perform laser marking on the part on the target tooling seat, and write the current tooling seat into the marked and retained state after marking is completed, so that the part remains on the original tooling seat and enters the painting process.

[0009] In a preferred embodiment, the part reference feature includes at least one of a reference hole, reference edge, contour corner, positioning notch, or preset identification area on the part surface; the tooling reference feature includes at least one of a tooling mark, reference hole, reference edge, or positioning notch on the tooling base.

[0010] In a preferred embodiment, the reference detection device includes an industrial camera and a coaxial light source;

[0011] The industrial camera is used to acquire image data of the tooling and parts, the coaxial light source is used to improve the imaging clarity of the surface features of the parts, and the reference detection device is used to extract reference features of the parts and reference features of the tooling.

[0012] In a preferred embodiment, the tooling base includes a tooling base body, a positioning reference surface, a lateral limiting part, and an elastic holding part; the positioning reference surface is used to provide a placement reference for the part, the lateral limiting part is used to limit the lateral movement of the part; the elastic holding part is a holding structure with adjustable preload, used to apply an elastic holding force to the part.

[0013] In a preferred embodiment, the elastic holding part is a spring push rod mechanism or a pneumatic holding mechanism; the tooling seat adopts a detachable sub-tooling structure, the tooling seat is fixedly installed on the support plate to complete the marking, and after the marking is completed, it is removed from the support plate as a whole and enters the painting process together with the parts.

[0014] In a preferred embodiment, the laser marking device includes a laser, a galvanometer scanning assembly, and a focusing assembly; the support drive device includes a servo motor, a speed reduction transmission device, a braking and holding device, and an encoder; the status acquisition device includes a station presence sensor, a pressure displacement sensor, and a vibration detection unit; the galvanometer scanning assembly performs plane compensation based on the verified plane deviation within the static marking window and completes laser marking within the marking area.

[0015] A laser marking method includes the following steps: mounting multiple parts to be marked onto multiple fixtures of a rotatable part support, ensuring each part forms a stable fit with the positioning reference surface, lateral limiting part, and elastic holding part of the corresponding fixture; reading the detection results from a status acquisition device and calling a reference detection device to acquire images of each fixture, combining sensor information and image recognition results to establish the occupancy status of each fixture; for candidate fixtures, extracting part reference features and fixture reference features, and establishing the planar deviation and angular deviation of the current part relative to the fixture; and marking the part against the fixture based on the planar deviation, angular deviation, support operating status, and painting process. Requirements for attitude maintenance, tooling docking direction, and flow sequence are established. Process load values, mechanical constraint values, and cross-process retention values ​​are established, and boundary modulation values ​​are generated. The state machine boundary corresponding to the current candidate tooling is updated based on the boundary modulation values. The rotatable part support is controlled to rotate toward the target tooling, and when the marking conditions are met, the laser is controlled to obtain light emission permission. The galvanometer scanning component performs plane compensation based on the verified plane deviation, and then laser marking is completed in the marking area. After the current tooling is marked, the tooling is written to the marked and retained state, and the next tooling that has not been marked is selected until all valid toolings in the current batch are marked.

[0016] In a preferred embodiment, after establishing the planar deviation, the method further includes establishing an additional eccentric radius: establishing an additional eccentric radius of the part relative to the theoretical center of the tooling based on the planar deviation of the current candidate tooling seat; establishing a maximum permissible angular acceleration boundary based on the additional eccentric radius to constrain the maximum angular acceleration during the rotation process; and decreasing the corresponding maximum permissible angular acceleration when the additional eccentric radius increases.

[0017] In a preferred embodiment, the step of controlling the rotatable part holder to rotate toward the target fixture includes: starting from the current docking angle position, driving the rotatable part holder to rotate toward the target fixture along the shortest effective path, and switching to the fine rotation state after the remaining angular distance enters the cutting boundary; in the fine rotation state, allocating the angular deviation of the current part to the rotatable part holder, which then undertakes the angular compensation; after the fine rotation is completed, re-collecting the part reference features and fixture reference features of the target fixture, and comparing the deviation changes before and after rotation; for fixtures that have passed the verification, entering the position holding state; when the holding time of the current fixture reaches the preset boundary, and the instantaneous angular velocity fed back by the encoder is lower than the stable threshold, entering the static marking window.

[0018] In a preferred embodiment, the step of updating the state machine boundary corresponding to the current candidate tooling based on the boundary modulation value includes updating the entry boundary from coarse to fine indexing, the planar residual allowance boundary, the angular residual allowance boundary, the holding time boundary before marking, and the maximum angular acceleration boundary during the indexing process; the step of establishing the process load value includes establishing the process load value based on the pattern area, pattern complexity, accuracy level, and program switching cost of the part corresponding to the current candidate tooling; the step of establishing the mechanical constraint value includes establishing the mechanical constraint value based on the planar deviation, support vibration attenuation state, clamping stability state, and indexing path of the part corresponding to the current candidate tooling. The mechanical constraint value is established for the diameter length; the step of establishing the cross-process retention value includes establishing the cross-process retention value according to the requirements of the painting process for attitude maintenance, tooling docking direction and flow sequence; after the fine rotation is completed, when the change in plane deviation and the change in angular deviation after verification exceed the preset threshold, it is determined that the current tooling seat has a risk of secondary attitude drift; for the tooling seat with a risk of secondary attitude drift, the controller executes at least one of the following strategies: reduce the angular acceleration boundary during subsequent retry, extend the holding time boundary, and perform a fine rotation and verification again; when multiple verifications fail, the current tooling seat is marked as abnormal and skipped.

[0019] The technical effects and advantages of the automated laser marking machine and laser marking method of the present invention are as follows:

[0020] This invention enables multiple parts to be calibrated to achieve continuous automatic rotation and calibration on the same equipment by setting up a rotatable part support with multiple tooling seats and combining it with the coordinated control of a reference detection device, a status acquisition device and a controller. At the same time, by establishing the occupied status of the tooling seats and shielding the idle tooling seats, the idling problem caused by traditional station-by-station polling is avoided, thereby reducing manual intervention and invalid waiting time, improving the efficiency of multi-station continuous processing and the stability of equipment cycle time.

[0021] This invention extracts the planar and angular deviations of a part, assigns the angular deviation to the rotatable part support for macroscopic compensation, and assigns the planar deviation to the galvanometer scanning assembly for microscopic compensation, thus achieving decoupled error control between macroscopic angular compensation and microscopic planar compensation. Simultaneously, by establishing an additional eccentric radius based on the planar deviation and constraining the angular acceleration during the rotation process according to this additional eccentric radius, the risk of secondary slippage and attitude drift during high-speed rotation of the part can be reduced, thereby improving marking and positioning accuracy, processing stability, and product consistency.

[0022] This invention establishes process load values, mechanical constraint values, and cross-process retention values, and generates boundary modulation values ​​to update the state machine boundaries. This enables the equipment to adaptively adjust the indexing and marking process according to different part states, different marking tasks, and different requirements of subsequent processes, thereby improving the system's adaptability to tasks with multiple patterns, quantities, and operating conditions. In addition, this invention allows the marked parts to enter the painting process while maintaining their original tooling state, reducing repeated clamping and realigning in subsequent processes, and improving process connection efficiency and overall line coordination efficiency. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of an automated laser marking machine provided in an embodiment of the present invention.

[0024] Figure 2 This is a schematic diagram of the internal assembly structure of an automated laser marking machine provided in an embodiment of the present invention.

[0025] Figure 3 This is a partial structural diagram of the tooling base provided in an embodiment of the present invention.

[0026] Figure 4 This is a block diagram of the control system module provided in an embodiment of the present invention.

[0027] Figure 5 A flowchart of an automated laser marking method provided in an embodiment of the present invention.

[0028] Figure 6 This is a schematic diagram of the underlying rotating state machine provided in an embodiment of the present invention.

[0029] Figure 7 This is a schematic diagram of the shielding and straddle-type indexing of the unloaded tooling seat provided in an embodiment of the present invention.

[0030] Figure 8 An adaptive acceleration / deceleration curve provided for an embodiment of the present invention.

[0031] 100. Automated laser marking machine; 110. Frame; 200. Laser marking device; 210. Laser; 220. Galvanometer scanning assembly; 230. Focusing assembly; 300. Reference detection device; 310. Industrial camera; 320. Coaxial light source; 400. Rotatable part support; 410. Central shaft; 420. Support plate; 430. Tooling base; 431. Tooling base body; 432. Positioning reference surface; 433. Lateral limiting part; 434. Elastic holding part; 500. Part; 510. Part reference feature; 520. Marking area; 600. Support drive device; 610. Servo motor; 620. Reduction transmission device; 630. Braking and holding device; 640. Encoder; 700. Status acquisition device; 710. Station presence / absence sensor; 720. Holding displacement sensor; 730. Vibration detection unit; 800. Controller. Detailed Implementation

[0032] 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.

[0033] Example 1: This example provides an automated laser marking machine 100, which is used to continuously and automatically mark multiple parts 500 to be marked, and after the marking is completed, keep the parts 500 in the original tooling holder 430 in a clamped state so that they can enter the painting process later.

[0034] Please see Figure 1 and Figure 2 The automated laser marking machine 100 includes a frame 110, a laser marking device 200, a reference detection device 300, a rotatable part support 400, a support drive device 600, a status acquisition device 700, and a controller 800.

[0035] The frame 110 is used to support and install various functional components; the laser marking device 200 is located on the upper part of the frame 110; the rotatable part support 400 is located below the laser marking device 200; the reference detection device 300 is used to detect the reference features of the part 500 and the tooling base 430; the support drive device 600 is used to drive the rotatable part support 400 to rotate; the state acquisition device 700 is used to acquire the tooling state and the support running state; the controller 800 is connected to the laser marking device 200, the reference detection device 300, the support drive device 600 and the state acquisition device 700 respectively, and is used to complete parameter modeling, boundary modulation, state machine management and marking control.

[0036] For ease of understanding, the automated laser marking machine 100 in this embodiment does not adopt the traditional single-piece operation mode of manual picking, placing, aligning and marking each piece. Instead, it uses a rotatable part support 400 to carry multiple parts 500 at a time, and uses a controller 800 to screen, rotate, check and mark each tooling seat 430, thereby achieving continuous automatic processing.

[0037] The laser marking device 200 preferably includes a laser 210, a galvanometer scanning assembly 220, and a focusing assembly 230;

[0038] The laser 210 is used to emit a marking laser beam; the galvanometer scanning assembly 220 is used to control the laser beam to perform two-dimensional scanning within the marking area 520 on the surface of the part 500; the focusing assembly 230 is used to adjust the laser focal point position so that the laser beam can maintain a good focusing state under different height conditions of the part 500.

[0039] In this embodiment, the laser marking device 200 is preferably fixed, meaning that its body does not rotate with the rotatable part support 400 during operation. Instead, the rotatable part support 400 transfers the target tooling 430 to below the marking window, and then the laser marking device 200 performs marking on the target part 500. This arrangement helps maintain the stability of the laser head position and facilitates subsequent error decoupling control between the macroscopic angular compensation of the support and the microscopic planar compensation of the galvanometer.

[0040] The reference detection device 300 preferably includes an industrial camera 310 and a coaxial light source 320;

[0041] The reference detection device 300 is used to identify the part reference feature 510 on the part 500 and the tooling reference feature on the tooling base 430.

[0042] In this embodiment, the part reference feature 510 can be any one or more combinations of a reference hole, reference edge, contour corner, positioning notch, or preset identification area; the reference detection device 300 can identify the marking part, reference hole, reference edge, or positioning notch on the tooling base 430. By simultaneously identifying the part reference feature 510 and the tooling reference feature, the controller 800 can establish the deviation relationship between the part 500 and the tooling and the deviation relationship between the tooling and the marking window, thereby improving the reliability of positioning and verification.

[0043] In one embodiment, the image acquisition parameters of the reference detection device 300 are set according to the size and marking accuracy requirements of the part 500, and the part reference feature 510 and tooling reference feature are identified by at least one of template matching, contour extraction, edge detection or corner point extraction; preferably, the identification accuracy of the reference detection device 300 reaches below millimeter level to meet the subsequent requirements for planar deviation and angular deviation modeling.

[0044] The rotatable part support 400 includes a central rotating shaft 410, a support plate 420, and multiple tooling seats 430.

[0045] The support plate 420 is mounted on the central rotating shaft 410 and can perform intermittent or continuous rotational movements around the central rotating shaft 410; multiple tooling seats 430 are arranged at intervals along the circumference of the support plate 420. Each tooling seat 430 is used to support a part 500 to be marked.

[0046] Please see Figure 3 Preferably, the solid structure of the tooling base 430 mainly includes a tooling base body 431, a positioning reference surface 432, a lateral limiting part 433, and an elastic pressing part 434.

[0047] The tooling base body 431 is used to support the part 500; the positioning reference surface 432 is used to provide a placement reference for the part 500; the lateral limiting part 433 is used to restrict the lateral movement of the part 500; and the elastic holding part 434 is used to apply a holding force to the part 500 so that the part 500 remains basically stable during the rotation and marking process.

[0048] The tooling base 430 is further defined or provided with supporting functional areas and interfaces. Specifically, the surface of the tooling base 430 is provided with a tooling marking part for the reference detection device 300 to identify; the internal space of the tooling base body 431 defines a part accommodating area for placing the part 500; the exterior of the tooling base body 431 is also provided with a transfer interface for mechanical docking with subsequent painting stations, transfer robots or downstream fixtures, and a passage or non-obstructed area is reserved for subsequent painting processes as a painting avoidance area.

[0049] In one embodiment, the preload of the elastic holding part 434 is set according to the material, thickness and limiting method of the part 500, and is achieved by adjusting the preload amount or the drive parameters.

[0050] In this embodiment, the tooling base 430 preferably adopts a detachable sub-tooling structure. That is, the tooling base 430 can be fixedly installed on the support plate 420 for marking, or it can be completely removed from the support plate 420 after marking and enter the subsequent painting process together with the part 500. With this structure, the part 500 can remain in the original tooling base 430 after marking, thereby reducing secondary clamping and realignment, and improving the efficiency of the entire production line.

[0051] The bracket drive device 600 includes a servo motor 610, a speed reduction transmission device 620, a brake holding device 630, and an encoder 640.

[0052] The servo motor 610 is used to output drive torque; the reduction transmission device 620 is used to improve the low-speed control resolution and docking stability of the rotatable part support 400; the brake holding device 630 is used to brake and hold the rotatable part support 400 when it docks with the target tooling seat 430; the encoder 640 is used to collect the angular position, angular velocity and angular acceleration information of the rotatable part support 400 in real time.

[0053] In this embodiment, the support drive device 600 not only undertakes the basic workstation transfer function, but also performs macroscopic angular compensation, that is, controls the rotatable part support 400 to directly absorb most of the angular deviation of the target part 500 when it stops, so as to reduce the excessive overall rotation compensation amount borne by the galvanometer scanning assembly 220.

[0054] The status acquisition device 700 includes a station presence / absence sensor 710, a pressure displacement sensor 720, and a vibration detection unit 730.

[0055] In one embodiment, the vibration detection unit 730 uses the instantaneous angular velocity fluctuation fed back by the encoder 640, the micro-amplitude value after the support stops, or a combination of both as the basis for stability determination. After the target tooling 430 enters the position holding state, the controller 800 continuously detects the instantaneous angular velocity fluctuation or micro-amplitude value; when it is lower than the stability threshold within a preset duration, it determines that the rotatable part support 400 has entered the stationary marking window;

[0056] Preferably, the preset duration can be set to 20 milliseconds to 100 milliseconds, and the stability threshold is pre-calibrated and written into the controller 800 according to the precision level of part 500 and the rotational inertia of the bracket.

[0057] The workstation presence sensor 710 is used to determine whether a part 500 is loaded on the corresponding tooling base 430; the pressing displacement sensor 720 is used to detect whether the elastic pressing part 434 is in an effective pressing state, so as to determine whether there is a risk of the part 500 being loosened or lifted; the vibration detection unit 730 is used to detect the residual vibration or speed fluctuation of the rotatable part support 400 after it stops.

[0058] In this embodiment, the controller 800 establishes an occupancy status based on the output of the workstation presence / absence sensor 710 and the image recognition result of the reference detection device 300, thereby forming a set of effective tooling seats 430, and automatically shielding the unloaded tooling seats 430 during the subsequent rotation process.

[0059] Please see Figure 4 The controller 800 preferably includes functional units such as parameter modeling, boundary modulation, state machine management, and tooling state storage.

[0060] Specifically, parameter modeling is used to establish process load values, mechanical constraint values, and cross-process retention values ​​based on data collected by the reference detection device 300 and the state acquisition device 700; boundary modulation is used to generate boundary modulation values ​​based on the modeling results and update the migration boundary of the bottom-level rotation state machine of the rotatable part support 400 according to the boundary modulation values; state machine management is used to control the rotatable part support 400 to gradually enter states such as coarse indexing, fine indexing, residual verification, position holding, and static marking from the standby state; and tooling retention state storage is used to record the state information of the marked tooling seat 430 for subsequent painting processes to read and call.

[0061] In this embodiment, the controller 800 does not use a simple rule tree to directly determine the final action. Instead, it first establishes a parameter model, then modulates the boundary of the underlying state machine, and finally drives the rotatable part support 400 to gradually evolve to a state suitable for marking under boundary constraints.

[0062] This embodiment further includes a painting process, which may include a painting station, a transfer robot, and a downstream fixture.

[0063] After marking is completed, part 500 is preferably not removed from the fixture 430, but remains in its original clamped state. At this time, it can enter the painting process in any of the following ways: one way is to keep the entire rotatable part support 400 intact and transfer the whole tray to the painting station; another way is to remove the individual fixture 430 from the support tray 420 and load it into the downstream fixture through the transfer interface; yet another way is to have the transfer robot directly grab the fixture 430 instead of directly grabbing part 500.

[0064] The above settings enable the marking and painting processes to maintain a unified tooling standard, thereby improving the overall production line's turnover value.

[0065] This first embodiment mainly completes the specific disclosure of the present invention from the perspective of device structure, clarifying the overall composition, the relationship between each device, the structure of tooling base 430, the drive and detection structure, and the internal functional division of controller 800, thereby providing a complete hardware foundation for the implementation of subsequent method processes.

[0066] Example 2: This example provides a laser marking method based on the aforementioned automated laser marking machine 100. The method is based on a multi-station tooling base 430, with multi-source parameter modeling and low-level state machine boundary modulation as its core, a static marking window as the execution condition, and cross-process retention of the same tooling as the subsequent connection method.

[0067] Please see Figure 5 The laser marking method preferably includes the following steps:

[0068] Step S1: Multiple parts 500 to be marked are respectively loaded into multiple tooling seats 430 of the rotatable part support 400, and each part 500 is stably engaged with the positioning reference surface 432, the lateral limiting part 433 and the elastic pressing part 434 of the corresponding tooling seat 430.

[0069] Step S2, combined Figure 7 As shown, the controller 800 reads the detection results of the presence / absence sensor 710 at the workstation and calls the reference detection device 300 to perform image acquisition on each fixture 430. Combining the sensor information and image recognition results, the controller establishes the occupancy status of each fixture 430, forms a set of valid fixtures 430, and masks the unloaded fixtures 430 from the candidate migration paths.

[0070] In step S3, for the candidate tooling base 430, the reference detection device 300 extracts the part reference feature 510 and the tooling reference feature, and establishes the planar deviation and angular deviation of the current part 500 relative to the tooling base 430; the planar deviation is used to characterize the translation amount of the part 500 in the local coordinate system of the tooling, and the angular deviation is used to characterize the rotation error of the part 500 relative to the theoretical placement direction.

[0071] Step S4: Calculate the additional eccentricity radius of the current candidate tooling seat 430 based on the planar deviation; the preferred calculation formula is as follows: ; in: This represents the additional eccentricity radius of part 500 on the i-th tooling fixture 430 relative to the theoretical center of the tooling, in millimeters; This represents the offset of part 500 on the i-th fixture 430 in the lateral direction, in millimeters; This represents the offset of part 500 on the i-th fixture 430 in the longitudinal direction, in millimeters; This model allows plane deviations to be further transformed into fundamental quantities for subsequent dynamic modulation.

[0072] Step S5: The controller 800 establishes the process load value based on the pattern area, pattern complexity, accuracy level, and program switching cost of the part 500 corresponding to the current candidate tooling 430; the preferred calculation formula is as follows: ; in: This represents the process load value of part 500 corresponding to the i-th tooling fixture 430; Indicates the pattern area factor; This represents the pattern complexity factor; Indicates the precision level factor; Indicates the program switching cost factor; , , and These represent the weights of the pattern area factor, pattern complexity factor, accuracy level factor, and program switching cost factor, respectively. In practical applications, the pattern area factor can be obtained by the ratio of the actual marked area to the allowable safe marked area. The pattern complexity factor can be obtained by normalizing the stroke density, the number of contour segments, or the density of path turning points. The accuracy level factor can be discretely assigned values ​​according to low, medium, and high levels. The program switching cost factor can be discretely assigned values ​​according to the switching complexity between the current program and the target program.

[0073] In step S6, the controller 800 establishes mechanical constraint values ​​based on the additional eccentric radius, the vibration attenuation state of the support, the clamping stability state, and the rotation path length. The preferred calculation formula is as follows: ; in: This represents the mechanical constraint value corresponding to the i-th tooling fixture 430; Indicates the eccentricity factor; Indicates the vibration attenuation factor; This indicates the presence of an unstable factor. Indicates path factor; , , and These represent the weights of the eccentricity factor, vibration attenuation factor, clamping instability factor, and path factor, respectively. This model is used to reflect the stability requirements of the current candidate tooling 430 during the indexing and docking phases. In one embodiment, the input factors in the process load value and mechanical constraint value are preferably normalized before entering the modeling process, so as to map parameters of different dimensions to a unified numerical range.

[0074] The pattern area factor, pattern complexity factor, and program switching cost factor are quantified based on the current task characteristics; the eccentricity factor is quantified based on the additional eccentricity radius; the vibration attenuation factor is quantified based on the residual vibration amplitude, velocity fluctuation, or a combination of both; and the clamping stability factor is quantified based on the clamping state of the elastic clamping part 434.

[0075] In step S7, the controller 800 establishes cross-process retention values ​​based on the requirements of subsequent painting processes for posture maintenance, tooling docking direction, and flow sequence; preferably, a discrete hierarchical method is adopted: when there are no specific requirements, a low value is taken; when there is a single posture or docking requirement, a medium value is taken; when there are multiple requirements at the same time or when priority flow is required, a high value is taken.

[0076] Preferably, the cross-process retention value is represented by a normalized scalar value. The tooling base 430 without specific connection requirements is assigned a lower value, the tooling base 430 with a single posture maintenance requirement is assigned a medium value, and the tooling base 430 with multiple high-precision connection requirements is assigned a higher value.

[0077] This value reflects the importance of the current fixture 430 maintaining its original clamping state after marking and entering the painting process.

[0078] Step S8: After obtaining the process load value, mechanical constraint value, and cross-process retention value, the controller 800 generates the boundary modulation value. The preferred calculation formula is as follows: ; in: This represents the boundary modulation value of the i-th tool holder 430; This represents the cross-process retention value of the i-th tooling fixture 430; , and These represent the fusion weights of process load value, mechanical constraint value, and cross-process retention value, respectively.

[0079] In one embodiment, the fusion weights corresponding to the process load value, mechanical constraint value, and cross-process retention value satisfy a constant sum, and the controller 800 dynamically adjusts them according to the current batch task type; When processing heavy-duty hardware parts with high eccentricity, increase the fusion weight corresponding to the mechanical constraint value; when processing electronic components with complex patterns and high precision requirements, increase the fusion weight corresponding to the process load value; when the painting process has high requirements for tooling posture maintenance and tooling docking direction, increase the fusion weight corresponding to the cross-process retention value.

[0080] Preferably, the controller 800 pre-stores multiple sets of weight combinations corresponding to different processing scenarios and automatically selects them according to the part 500 category, pattern task type and subsequent process requirements; It should be noted that the boundary modulation value is not directly used as a motor action command, but is used to update the migration boundary in the bottom rotating state machine of the rotatable part support 400.

[0081] For step S9, please refer to [link / reference]. Figure 8 To reduce the risk of secondary slippage of the eccentric part 500 during the rotation process, the controller 800 establishes a maximum allowable angular acceleration model based on the additional eccentric radius; the preferred calculation formula is as follows: ; in: This represents the maximum permissible angular acceleration during the indexing process corresponding to the i-th tool holder 430; This represents the reference angular acceleration of the system under standard loading conditions; Indicates the eccentricity sensitivity coefficient; The meaning of this model is: the greater the eccentricity of part 500, the smaller the allowable rotation angle acceleration, so that the corresponding tooling 430 can obtain a smoother acceleration and deceleration curve during the rotation process. The eccentricity sensitivity coefficient used to establish the maximum permissible angular acceleration boundary is pre-calibrated according to the quality grade, clamping method and limit degree of part 500 and written into the parameter table of controller 800; controller 800 calls the corresponding eccentricity sensitivity coefficient according to the current part 500 category to establish the maximum permissible angular acceleration boundary adapted to the current working condition.

[0082] In step S10, the controller 800 updates the state machine boundary corresponding to the current candidate tooling 430 based on the boundary modulation value and the maximum permissible angular acceleration model. This includes at least the following: the entry boundary from coarse to fine indexing; the planar residual permissible boundary; the angular residual permissible boundary; the holding time boundary before marking; and the maximum angular acceleration boundary during the indexing process.

[0083] In one embodiment, the controller 800 has a built-in state machine boundary mapping table and updates the state machine boundary corresponding to the current candidate tooling 430 in a hierarchical manner using the boundary modulation value as an index.

[0084] The boundary modulation value can be divided into a low-sensitivity range, a medium-sensitivity range, and a high-sensitivity range. When the boundary modulation value is in the low-sensitivity range, the controller 800 uses a shorter deceleration advance and a shorter pre-marking hold time. When the boundary modulation value is in the medium-sensitivity range, the controller 800 uses a medium deceleration advance and a medium hold time. When the boundary modulation value is in the high-sensitivity range, the controller 800 uses a longer deceleration advance, a longer hold time, and a stricter residual allowance range.

[0085] Preferably, the state machine boundary mapping table is pre-stored in the controller 800 and can be updated according to the part 500 category and process task; In this embodiment, a hierarchical lookup table method can be preferred to complete the boundary update. The tooling 430 with a smaller boundary modulation value adopts a narrower deceleration advance and a shorter holding time, while the tooling 430 with a larger boundary modulation value adopts an earlier fine indexing entry, a stricter residual allowance, and a longer static holding time.

[0086] In step S11, the controller 800 starts from the current docking angle position and drives the rotatable part support 400 to rotate toward the target tooling seat 430 along the shortest effective path. During this stage, it approaches quickly at a higher speed, but the angular acceleration must not exceed the maximum allowable angular acceleration boundary corresponding to the current tooling seat 430.

[0087] Step S12: When the remaining angular distance between the current docking angle and the target docking angle enters the cutting boundary, the controller 800 switches to the fine rotation state. The controller 800 prioritizes the angular deviation of the current part 500 to the rotatable part support 400, and the docking angle of the support bears the main angular compensation, so that the part 500 completes the macroscopic angle correction at the mechanical level. In this way, all angular deviations can be avoided by having the galvanometer scanning assembly 220 handle them, thereby reducing the impact of large-angle optical compensation on the marking quality.

[0088] Step S13: After the fine indexing is completed, the reference detection device 300 re-acquires the part reference feature 510 and the tooling reference feature of the target tooling 430, and compares the deviation changes before and after indexing. When the changes in planar deviation and angular deviation are both within the allowable range after verification, it is determined that the current fixture 430 has not experienced significant secondary slippage and can proceed to the next state; when the deviation changes exceed the threshold, it is determined that the current fixture 430 has a risk of secondary attitude drift.

[0089] In one embodiment, the threshold values ​​for planar deviation change and angular deviation change under the residual verification state are set in stages according to the accuracy level of part 500. For high-precision electronic structural components, the threshold values ​​for planar deviation change and angular deviation change can be set to a smaller range; for ordinary hardware parts, the threshold values ​​for planar deviation change and angular deviation change can be appropriately relaxed.

[0090] Preferably, the threshold for the change in planar deviation can be set between 0.02 mm and 0.10 mm, and the threshold for the change in angular deviation can be set at... to between.

[0091] Furthermore, the controller 800 establishes an additional eccentric radius based on the planar deviation of the part 500 corresponding to the current candidate tooling 430, and uses the additional eccentric radius as the input quantity of the indexing dynamics constraint; the larger the additional eccentric radius, the smaller the allowable angular acceleration of the corresponding tooling 430 during the indexing process.

[0092] For fixture 430 which has the risk of attitude drift, controller 800 may execute any of the following strategies: reduce the angular acceleration boundary during subsequent retries; extend the holding time boundary; perform a fine rotation and verification again; if multiple verifications fail, mark fixture 430 as abnormal and skip it.

[0093] In one embodiment, when the same fixture 430 fails multiple consecutive indexing and residual verifications, the controller 800 marks the fixture 430 as an abnormal fixture 430 and skips it, and then drives the rotatable part support 400 to index to the next valid fixture 430 to maintain the processing cycle of the current batch.

[0094] Preferably, the number of consecutive multiple times can be set to 2 to 5 times, and more preferably 3 times.

[0095] After all valid tooling seats 430 in the current batch have been marked, the controller 800 will centrally transfer the abnormal tooling seats 430 to the loading and unloading area and trigger an alarm or prompt for manual verification.

[0096] By using the above methods, we can avoid a single abnormal tooling fixture 430 occupying the equipment cycle time for a long time, while ensuring that abnormal parts 500 can still be processed centrally later.

[0097] In step S14, for the tooling 430 that has passed the review, the controller 800 activates the brake holding device 630 and continuously monitors the residual vibration and speed fluctuation of the bracket. When the holding time of the current tooling 430 reaches the preset boundary and the instantaneous angular velocity fed back by the encoder 640 is lower than the stable threshold, it is considered to have entered the static marking window.

[0098] In step S15, within the stationary marking window, the laser 210 obtains light emission permission, the galvanometer scanning assembly 220 performs micro-plane compensation based on the verified plane deviation, and undertakes a small amount of residual angular compensation when necessary, and then completes laser marking within the marking area 520.

[0099] In this embodiment, the galvanometer scanning component 220 mainly undertakes the micro-compensation of planar deviation, rather than the task of large-angle overall compensation, thereby forming an error decoupling control mode of macro-angular compensation of the support plus micro-planar compensation of the galvanometer.

[0100] In step S16, after the current fixture 430 has been marked, the controller 800 does not control the elastic holding part 434 to release the part 500, but instead writes the marked and reserved state of the fixture 430. The reserved state of the fixture records at least: the fixture 430 number, the marked mark, the current posture information, and the retention requirements corresponding to the subsequent painting process.

[0101] In step S17, the controller 800 returns to the set of valid tooling seats 430 and continues to select the next tooling seat 430 that has not been marked. The above steps are repeated until all valid tooling seats 430 in the current batch have been marked.

[0102] In step S18, for tooling 430 that fails to meet the requirements in occupancy detection, deviation detection, residual verification, or clamping status detection, the controller 800 moves it into the abnormal queue, triggers an alarm or uploads an abnormal record, and allows subsequent manual verification.

[0103] For a fixture 430 marked as abnormal, after manually confirming the orientation of part 500 and re-clamping it, an abnormal reset can be triggered by the controller 800. After receiving the abnormal reset command, the controller 800 clears the abnormal mark of the corresponding fixture 430 and makes it re-enter the residual review state. When the review is passed again, the fixture 430 is reconnected to the subsequent marking process.

[0104] Using the above method, the recovery process of the abnormal tooling seat 430 can be completed without affecting the cycle time of the other effective tooling seats 430.

[0105] Please combine Figure 6 To facilitate implementation by those skilled in the art, the method flow in this embodiment is preferably driven by a low-level rotating state machine, which includes at least:

[0106] Standby state, candidate preparation state, boundary modulation generation state, coarse transposition state, fine transposition state, residual verification state, position holding state, stationary marking state, tooling retention and locking state, next tooling holder 430 migration state, and abnormal skip state.

[0107] In this design, the controller 800 does not directly output the final action from the rule tree. Instead, it first generates a boundary modulation value, then uses this value to update the state transition boundary, and subsequently drives the rotatable part support 400 to evolve gradually under the constraints of the modulation boundary. This control method is more conducive to improving the adaptability of the equipment under different patterns, quantities, eccentric placements, and cross-process requirements.

[0108] By using the above method, this embodiment can achieve at least the following effects: By establishing an occupied status and shielding the unloaded fixture 430, the invalid idle time caused by missing workstations is reduced; By adding an eccentric radius model and a maximum allowable angular acceleration boundary, the risk of secondary slippage during the rotation process is reduced; By establishing boundary modulation values ​​through process load values, mechanical constraint values, and cross-process retention values, the pertinence of state machine control is improved. By decoupling macroscopic angular compensation and microscopic planar compensation, the accuracy and consistency of marking positioning are improved; The static marking window mechanism ensures that the marking process is carried out under relatively stable mechanical conditions. By using a tooling retention writing mechanism, part 500 can maintain its original tooling posture after marking and enter the painting process, thereby improving the overall line efficiency.

[0109] It should be noted that, for the sake of brevity, the foregoing method embodiments are described as a series of actions, but this does not mean that the application limits the order of the steps. Based on the ideas of this application, some steps can be executed in different orders or in parallel without affecting the functional implementation. Secondly, those skilled in the art should also understand that the specific embodiments described in the specification are preferred embodiments of the technical solutions of this application, and not limitations on the scope of protection of this application. All equivalent improvements or substitutions made within the spirit and principles of this application should be covered within the scope of protection of this application.

[0110] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An automated laser marking machine, characterized in that, It includes a frame, a laser marking device, a reference detection device, a rotatable part support, a support drive device, a status acquisition device, and a controller; the laser marking device is located on the upper part of the frame, and the rotatable part support is located below the laser marking device; The rotatable part support includes a central rotating shaft, a support plate, and multiple tooling seats. The support plate is mounted on the central rotating shaft, and the multiple tooling seats are spaced apart around the circumference of the support plate. Each tooling seat is used to support a part to be marked. The reference detection device is used to detect reference features of the part and the tooling base, the bracket driving device is used to drive the rotatable part bracket to rotate, and the status acquisition device is used to acquire the tooling status and the bracket operating status. The controller is connected to the laser marking device, reference detection device, bracket driving device, and state acquisition device, respectively. The controller is used to: establish the occupancy status of each tooling seat; extract part reference features and tooling reference features for candidate tooling seats, and establish the planar deviation and angular deviation of the current part relative to the tooling seat; establish process load value, mechanical constraint value, and cross-process retention value according to the planar deviation, angular deviation, bracket running status, and the requirements of the painting process for attitude maintenance, tooling docking direction, and flow sequence, and generate boundary modulation value; update the state machine boundary according to the boundary modulation value and control the rotation of the rotatable part bracket; when the marking conditions are met, control the laser marking device to perform laser marking on the part on the target tooling seat, and write the current tooling seat into the marked and retained state after marking is completed, so that the part remains on the original tooling seat and enters the painting process.

2. The automated laser marking machine according to claim 1, characterized in that, The part reference features include at least one of the following on the part surface: reference hole, reference edge, contour corner, positioning notch, or preset identification area; The tooling reference features include at least one of the following: tooling markings, reference holes, reference edges, or positioning notches on the tooling base.

3. An automated laser marking machine according to claim 2, characterized in that, The reference detection device includes an industrial camera and a coaxial light source; The industrial camera is used to acquire image data of the tooling and parts, and the coaxial light source is used to improve the imaging clarity of the surface features of the parts. The reference detection device is used to extract reference features of the parts and reference features of the tooling.

4. An automated laser marking machine according to claim 1, characterized in that, The tooling base includes a tooling base body, a positioning reference surface, a lateral limiting part, and an elastic pressing part; The positioning reference surface is used to provide a placement reference for the part, and the lateral limiting part is used to restrict the lateral movement of the part; The elastic holding part is a holding structure with adjustable preload, used to apply an elastic holding force to the part.

5. An automated laser marking machine according to claim 4, characterized in that, The elastic holding part is a spring push rod mechanism or a pneumatic holding mechanism; The tooling base adopts a detachable sub-tooling structure. The tooling base is fixedly installed on the support plate to complete the marking. After the marking is completed, the entire tooling base is removed from the support plate and enters the painting process together with the parts.

6. An automated laser marking machine according to claim 1, characterized in that, The laser marking device includes a laser, a galvanometer scanning assembly, and a focusing assembly; The bracket drive device includes a servo motor, a reduction transmission device, a brake holding device, and an encoder; The status acquisition device includes a workstation presence / absence sensor, a pressure displacement sensor, and a vibration detection unit. The galvanometer scanning assembly performs planar compensation based on the verified planar deviation within the stationary marking window and completes laser marking within the marking area.

7. A laser marking method, characterized in that, Includes the following steps: Multiple parts to be marked are respectively loaded into multiple tooling seats of a rotatable part holder, and each part forms a stable fit with the positioning reference surface, lateral limiting part and elastic holding part of the corresponding tooling seat. Read the detection results from the status acquisition device, call the reference detection device to acquire images of each tooling, and combine the sensor information and image recognition results to establish the occupancy status of each tooling. For candidate tooling, extract part reference features and tooling reference features, and establish the planar deviation and angular deviation of the current part relative to the tooling. Based on the requirements of planar deviation, angular deviation, support operation status, and painting process for posture maintenance, tooling docking direction, and flow sequence, process load values, mechanical constraint values, and cross-process retention values ​​are established, and boundary modulation values ​​are generated. Update the state machine boundary corresponding to the current candidate tooling based on the boundary modulation value; The rotatable part support is controlled to rotate toward the target tooling, and when the marking conditions are met, the laser is controlled to obtain light emission permission. The galvanometer scanning assembly performs plane compensation based on the verified plane deviation, and then laser marking is completed in the marking area. After the current fixture is marked, the fixture is written to the marked and reserved state, and the next fixture that has not been marked is selected until all valid fixtures in the current batch are marked.

8. The laser marking method according to claim 7, characterized in that, After establishing the plane deviation, the step of establishing the additional eccentric radius is also included: Establish the additional eccentricity radius of the part relative to the theoretical center of the tooling based on the planar deviation of the current candidate tooling base; The maximum permissible angular acceleration boundary is established based on the additional eccentric radius to constrain the maximum angular acceleration during the rotation process; As the additional eccentric radius increases, the corresponding maximum permissible angular acceleration decreases.

9. The laser marking method according to claim 8, characterized in that, The step of controlling the rotation of the rotatable part support toward the target tooling base includes: Starting from the current docking angle position, drive the rotatable part bracket to rotate toward the target tooling seat according to the shortest effective path, and switch to the fine indexing state after entering the cutting boundary with the remaining angular distance; In the fine indexing state, the angular deviation of the current part is assigned to the rotatable part support, and the rotatable part support undertakes the angular compensation; After the precision indexing is completed, the part reference features and tooling reference features of the target tooling are re-acquired, and the deviation changes before and after indexing are compared. For fixtures that have passed the verification, they enter the position holding state; when the holding time of the current fixture reaches the preset boundary and the instantaneous angular velocity fed back by the encoder is lower than the stable threshold, they enter the static marking window.

10. A laser marking method according to claim 9, characterized in that, The step of updating the state machine boundary corresponding to the current candidate tooling based on the boundary modulation value includes updating the entry boundary from coarse to fine rotation, the planar residual permission boundary, the angular residual permission boundary, the hold time boundary before marking, and the maximum angular acceleration boundary during the rotation process. The step of establishing the process load value includes establishing the process load value based on the pattern area, pattern complexity, accuracy level and program switching cost of the part corresponding to the current candidate tooling. The step of establishing mechanical constraint values ​​includes establishing mechanical constraint values ​​based on the planar deviation of the part corresponding to the current candidate tooling, the vibration attenuation state of the bracket, the clamping stability state, and the length of the rotation path. The step of establishing cross-process retention values ​​includes establishing cross-process retention values ​​based on the requirements of the painting process for posture maintenance, tooling docking direction, and flow sequence. After the fine rotation is completed, if the changes in planar deviation and angular deviation after verification exceed the preset thresholds, it is determined that the current fixture has a risk of secondary attitude drift. For fixtures with a risk of secondary attitude drift, the controller executes at least one of the following strategies: reducing the angular acceleration boundary during subsequent retries, extending the holding time boundary, and performing a fine rotation and verification again. If multiple reviews fail, the current fixture will be marked as abnormal and skipped.

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