A device and method for real-time adjustment of important parameters in synchronous laser-assisted processing

Abstract

The application discloses a device and method for adjusting important parameters in real time in synchronous laser-assisted machining, which comprises a machining platform, a laser module, a numerical control machine tool module, an industrial computer, a moving device, a detection module, a connecting device and a pose adjustment module. In the synchronous laser-assisted machining, the detection module detects the machining temperature field in real time, and the industrial computer controls the laser module, the numerical control machine tool module and the pose adjustment module in real time, so that the machining parameters such as laser power and tool-laser lag distance can be adjusted in real time. The application can adjust important machining parameters in real time according to the machining temperature field, avoids the use of unreasonable preset parameters in the machining process, reduces the adverse effects of fixed parameters on the machining quality of workpieces when the working conditions change, and meanwhile, the adaptive adjustment of main parameters by using a priority adjustment mode can make the use of the equipment more reasonable, and the energy utilization rate is improved.

Description

Technical Field

[0001] This invention belongs to the field of special processing and relates to a device and method for real-time adjustment of important parameters in synchronous laser-assisted processing. Background Technology

[0002] Materials such as laser crystals, optical glass, and fiber-reinforced ceramics are widely used in aerospace, industrial energy, and other fields due to their excellent mechanical properties. However, when these materials are processed in a conventional way, problems such as rapid tool wear, low processing quality, and inability to guarantee precision occur due to their high hardness and poor plasticity. Specialized machining has shown its advantages in addressing these problems.

[0003] Specialized machining includes methods such as electrical discharge machining (EDM), electron beam machining (EBM), and laser-assisted machining (LAM). EDM is suitable for machining conductive materials, while EBM has stringent environmental requirements. Compared to other specialized machining methods, laser-assisted machining has a wider range of applications, does not require specific material conductivity, can be performed in conventional machining environments, and effectively improves machining efficiency and reduces tool wear. Currently, this method is widely used for machining difficult-to-machine materials.

[0004] A common laser-assisted machining method involves simultaneously applying laser and mechanical processing to the workpiece. A high-energy laser beam serves as the heat source, heating the area to be processed by the cutting tool, causing a rapid increase in surface temperature and achieving surface modification for easier machining. Before laser-assisted machining, different processing parameters need to be set according to the material's characteristics. For example, in laser-assisted grinding, laser-related parameters include laser power and scanning speed; grinding-related parameters include spindle speed and grinding wheel feed rate. In addition, parameters such as laser defocusing and hysteresis distance need to be controlled. Hysteresis distance refers to the distance by which the cutting edge lags behind the center of the laser spot during processing. The optimal hysteresis distance is determined by the distance between the tool's softening temperature point and the highest temperature point in the laser irradiation temperature field. Maintaining the optimal hysteresis distance ensures that the material with the optimal surface modification can always be removed without the tool overheating and softening, thus preventing a decrease in its softening properties.

[0005] In synchronous laser-assisted machining, the laser irradiates the area to be machined in front of the tool to soften the material. The laser parameters, machining parameters, and the synergistic relationship between the two are particularly important for the high-quality and efficient machining of the workpiece.

[0006] Laser power primarily affects the temperature change of the irradiated area. Excessive power can ablate pits on the material surface, leading to uncontrollable workpiece quality in synchronous laser-assisted machining. The processed workpiece surface may have cracks and other damage, and a heat-affected zone may remain on the subsurface. Insufficient laser power, on the other hand, will not soften the material. Laser defocus refers to the vertical distance between the laser focus and the workpiece surface. Positive defocus means the focus is above the workpiece surface, while negative defocus means it is below. In negative defocus, the power density inside the material is higher than on the surface, resulting in greater laser penetration and a larger temperature gradient perpendicular to the surface, making subsurface damage more likely. Laser scanning speed affects heat accumulation in the material. Too slow a scanning speed leads to severe heat accumulation and increased subsurface damage. Too fast a scanning speed results in delayed heat transfer in the laser irradiation area, a smaller heating and modification zone, and the possibility of unmodified or insufficiently modified portions in the removed material, as well as increased tool wear. In summary, parameters such as laser power need to be adjusted in real time according to the working conditions; otherwise, consequences such as an increased heat-affected zone, severe subsurface damage, and reduced tool life may occur.

[0007] Hysteresis distance is a crucial parameter in synergistic laser and mechanical machining. If the hysteresis distance is too small, excessive tool temperature rise leads to decreased tool performance and compromised machining quality. Conversely, if the hysteresis distance is too large, the softened material in the machining area cannot be removed promptly, causing the material hardness to rise again and resulting in poor laser-assisted machining. Optimal hysteresis distance requires comprehensive consideration of the workpiece material softening temperature, the tool softening temperature, and the combined temperature field generated by laser irradiation and tool cutting. This requires coordination between the tool feed rate and the laser scanning speed during machining. However, in actual machining, this crucial parameter is not constant. Environmental factors such as air disturbances, machine vibrations, unstable laser power, and material heat accumulation can all cause variations in the machining temperature field, leading to deviations from the optimal hysteresis distance. Therefore, real-time adjustment of this parameter is essential.

[0008] Currently, laser-assisted machining technology has been applied to many types of difficult-to-machine materials. For example, Chinese patents "A Laser-Assisted Spot Grinding Method for Difficult-to-Machine Materials" and "A Laser-Assisted Cutting Method for Transparent Materials" (CN 109604832 A; CN 109454326 A) use finite element simulation to determine parameters such as laser power and hysteresis distance before machining, based on the temperature distribution of the material to be processed under laser heating. Then, the material is machined under the set machining parameters. However, due to uncertainties in the machining environment, material inhomogeneity, and potential tool wear, the heat generated by the laser and the heat dissipation between the workpiece, tool, and surrounding environment are all affected. Therefore, using the pre-set parameters inevitably has an adverse impact on the workpiece quality. For example, the Chinese patent "A laser-assisted grinding method for natural diamond scribing tools" (CN 109015131 B) uses a non-contact temperature sensor to measure the temperature information of the laser heating zone during processing and adjusts the output process parameters of the laser in real time to ensure high-quality processing of the diamond scribing tool edge. However, the grinding surface of the tool edge is heated by the laser while being ground by the grinding wheel. It does not take into account the situation where the grinding area lags behind the laser irradiation center. That is, it ignores the influence of the lag distance when the laser heats and modifies the area to be processed on the laser-assisted processing. Furthermore, it does not achieve real-time adjustment of the grinding wheel parameters. The laser heat transferred by the workpiece may reduce the hardness of the tool and aggravate the wear of the grinding wheel.

[0009] In summary, due to the existence of potential factors such as air disturbance, machine vibration, unstable equipment output, and defects in workpiece materials in the processing environment, variable parameter processing is required during laser-assisted processing. However, existing technologies have not achieved real-time adaptive adjustment of laser parameters, machining parameters, and hysteresis distance according to the on-site working conditions. Therefore, there is an urgent need for a device and method for real-time adjustment of important parameters in synchronous laser-assisted processing to solve the above problems. Summary of the Invention

[0010] In view of the problems mentioned in the background art, the present invention provides a device and method for real-time adjustment of important parameters in synchronous laser-assisted processing.

[0011] To achieve this objective, the technical solution adopted by the present invention is as follows:

[0012] A device for real-time adjustment of important parameters in synchronous laser-assisted processing includes a processing platform, as well as a laser module, a CNC machine tool module, an industrial computer, a moving device, a detection module, a connecting device, and a posture adjustment module;

[0013] The laser module includes a laser control line, a laser, and a laser head. Connected to an industrial computer, it executes commands from the industrial computer during processing and adjusts laser parameters in real time. The CNC machine tool module includes a cutting tool, a machine spindle, a machine tool control system, and machine tool control lines. Connected to the industrial computer, it executes commands from the industrial computer during processing and adjusts machining parameters in real time. The detection module includes a data transmission line and a thermal imager. Connected to the industrial computer, it collects and transmits the collected temperature field data to the industrial computer in real time. The pose adjustment module includes a precision XY displacement platform and displacement platform control lines. Controlled by the industrial computer, it adjusts the tool-laser hysteresis distance (the distance by which the tool's leading edge lags behind the laser spot) in real time during processing. The pose adjustment module and the CNC machine tool module are connected via the connecting device.

[0014] The detection module is connected to the mobile device, which is connected to the industrial control computer. The mobile device is used to execute the instructions issued by the industrial control computer during processing and adjust the position of the detection module.

[0015] Preferably, the industrial control computer receives temperature field data observed by the thermal imager in real time during processing, and detects and compares the real-time temperature field during processing according to preset parameters such as the optimal hysteresis distance and the melting point of the material. It records and analyzes the real-time temperature values ​​and actual hysteresis distances at various points on the workpiece surface in real time, and sends adjustment commands to each module in real time according to preset standards. The optimal hysteresis distance refers to the distance between the tool softening temperature point and the center point of the laser spot along the tool feed direction in the laser irradiation temperature field. Maintaining the optimal hysteresis distance can ensure that the material with the optimal surface modification can always be removed without the tool being heated and softened, thus reducing its performance.

[0016] Preferably, the thermal imager is fixed on a mobile device, which is driven by a servo motor to ensure the precise reciprocating motion of the thermal imager. The mobile device is placed near the processing area, and the moving speed of the thermal imager is the same as the feed speed of the tool, so that the camera of the thermal imager is always aligned with the laser heating area, ensuring that the real-time changing processing temperature field does not deviate from the imaging range of the thermal imager.

[0017] Preferably, the pose adjustment module is connected to the machine tool spindle via a connecting device, and the laser head is mounted on a precision XY displacement platform so that the laser always irradiates the area to be processed. The precision movement of the displacement platform is controlled by an industrial control computer to achieve real-time precision adjustment of the lag distance.

[0018] Preferably, the connecting device can be updated according to the processing requirements of end grinding, end milling and other processes. By cooperating with the precision XY displacement platform, the laser head can achieve five degrees of freedom of motion, including translation along three axes and rotation around the YZ axis. Different irradiation angles and heating ranges of the laser beam can be changed for end grinding, end milling and other working conditions.

[0019] Preferably, the workpiece can be a hard and brittle material that is difficult to process by traditional processing methods (engineering ceramics, fiber-reinforced composite materials, cemented carbide, etc.), or a material with high requirements for surface quality, processing accuracy and processing efficiency.

[0020] Preferably, the processing platform can be a vacuum adsorption platform to quickly fix and disassemble workpieces of block or thin plate shape, or it can be a special fixture designed according to the shape of the workpiece to achieve accurate positioning and clamping of workpieces with complex shapes.

[0021] Preferably, when milling or grinding, the cutting tool can be a milling cutter or a grinding wheel. Different processing requirements and different processing effects can be achieved by changing different types or models of cutting tools.

[0022] Preferably, a device and method for real-time adjustment of important parameters in synchronous laser-assisted machining are characterized by comprising the following steps during workpiece machining:

[0023] Step 1: Set the following standard values ​​in the industrial computer: laser power P (W), laser defocusing amount L 离焦 (mm), tool speed V (r / min), tool feed rate f (m / s), cutting width W 切削 (mm), Material melting point T 熔点 (°C), tool softening temperature T 刀具软化 (°C), Material softening temperature T 软化 (°C). Connect the thermal imager to the industrial computer and set its movement speed to the tool feed rate.

[0024] Step 2: Connect the industrial control computer to the laser module, CNC machine tool module, and posture adjustment module, and couple and control them respectively. The priority of each processing parameter adjustment is defined as follows: laser power or hysteresis distance > laser defocusing amount > tool feed speed > spindle speed. That is, when an abnormality is found in the processing temperature field, the high-priority processing parameter is adjusted first. If adjusting the high-priority parameter cannot restore the abnormality or the processing efficiency is reduced, then the next priority parameter is adjusted.

[0025] Step 3: Position and clamp the workpiece on the processing platform. According to the processing requirements, adjust the connecting device and control the precision XY displacement platform to move the laser spot to the surface of the workpiece to be heated and softened.

[0026] Taking into account factors such as processing quality, processing efficiency, and adjustment effect, the following real-time adjustment method for processing parameters is formulated to address common abnormal situations during processing:

[0027] (a-1). The thermal imager detected the highest temperature T in the temperature field of the area where the material to be removed. max Exceeding the material's melting point T 熔点 At this time, the industrial control computer controls the laser to reduce the laser output power;

[0028] (a-2). The thermal imager detected the lowest temperature T in the temperature field of the area where the material to be removed. min Below the material softening temperature T 软化 When the material's hardness and strength decrease by about 80% at this temperature, the industrial control computer controls the laser to increase the laser output power.

[0029] (b) The thermal imager detected the actual hysteresis distance L. 实际滞后 With the optimal lag distance L 最优滞后 When they are no longer equal, the industrial control computer controls the precision XY displacement platform to move the laser head in real time. 实际滞后 Greater than L 最优滞后 When the lag is small, the movement is in the negative direction of the Y-axis. When the lag is small, the movement direction is reversed. The movement distance is obtained by the difference between the actual lag distance and the optimal lag distance.

[0030] (c-1). The thermal imager detected the highest temperature T in the temperature field of the area where the material to be removed. max With the lowest value T min When the difference exceeds the rated value (which depends on the material properties), the material to be removed will soften unevenly, which will easily lead to increased tool wear. The industrial control computer controls the laser to increase the positive defocusing amount or decrease the negative defocusing amount.

[0031] (c-2). The thermal imager detected the highest temperature T in the temperature field of the area where the material to be removed. max With the lowest value T min When the difference between the two values ​​is lower than the rated value (which depends on the material properties), the depth of fully softened material is too shallow and less than the cutting depth of the tool. The industrial control computer controls the laser to increase the negative defocusing amount or decrease the positive defocusing amount.

[0032] (d-1). The thermal imager detected that the temperature field in the area of ​​material to be removed was between the highest temperature value T. max With the material softening temperature T 软化 Material width W 被软化材料 Less than the cutting width W 切削At this time, the material that is not fully softened will be cut off. The industrial control computer takes into account factors such as adjustment effect and processing efficiency and selects the control module according to priority. It prioritizes controlling the laser to increase the laser output power. When increasing the laser power will lead to a decrease in processing efficiency or an unsatisfactory adjustment effect, it increases the laser defocusing amount, or the CNC machine tool module reduces the feed speed.

[0033] (d-2). The thermal imager detected that the temperature field in the area of ​​material to be removed was between the highest temperature value T. max With the material softening temperature T 软化 Material width W 被软化材料 Greater than the cutting width W 切削 When the amount of material is twice or more, the softened material cannot be removed in one go. The industrial control computer takes into account factors such as adjustment effect and processing efficiency and selects the control module according to priority. It prioritizes controlling the laser to reduce the laser output power. When reducing the laser power will lead to a decrease in processing efficiency or an unsatisfactory adjustment effect, it will reduce the laser defocusing amount, or the CNC machine tool module will increase the feed speed.

[0034] (e) When the thermal imager detects that the temperature field in the area of ​​material to be removed is under suitable conditions (i.e., conditions abcd above are met), but the tool tip exceeds the tool softening temperature T under the combined effect of the laser beam and cutting heat. 刀具软化 When the hardness or strength of the cutting tool decreases by 20%, the industrial control computer controls the CNC machine tool to reduce the spindle speed and reduce cutting heat.

[0035] (f) When the thermal imager detects that the tool is about to cut into or out of the workpiece, the industrial control computer controls the laser module, CNC machine tool module, and posture adjustment module to open and close in a timely manner to increase energy utilization and avoid laser ablation of other devices besides the workpiece.

[0036] The present invention has the following beneficial effects:

[0037] (1) By adjusting important parameters such as laser power and tool-laser hysteresis distance in real time, the auxiliary effect of laser pre-softening of the material to be processed can be better realized, the wear of the tool can be reduced to a greater extent, and the service life of the tool can be greatly improved.

[0038] (2) The present invention can adjust the processing parameters in real time according to the on-site processing conditions, which reduces the adverse effects of fixed parameters on the processing quality of workpieces when faced with changes in working conditions. It can generally improve the quality of products, reduce the scrap rate, and increase efficiency.

[0039] (3) The present invention uses a priority parameter tuning method to adaptively adjust the main parameters such as laser power and tool main speed, which can make the use of the equipment more reasonable, avoid unnecessary waste of resources, and improve energy utilization.

[0040] (4) The present invention can detect and record in real time the temperature field data and laser power and other important processing parameters of a certain difficult-to-process material in synchronous laser-assisted processing, which can provide guidance for subsequent material processing and shorten the production cycle. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a schematic diagram of the area where the material to be removed and the area where the material has softened on the workpiece 2 in this invention.

[0043] Figure 2 This is a schematic diagram of the device for real-time adjustment of hysteresis distance in this invention.

[0044] Figure 3 This is a schematic diagram of the structure of the mobile device 6 in this invention.

[0045] Figure 4 This is a schematic diagram of the device for real-time adjustment of important parameters in synchronous laser-assisted processing in this invention.

[0046] Figure 5 This is a schematic diagram of the laser head 1-3 fixed on the precision XY displacement platform 9-1 in this invention.

[0047] Figure 6 This section describes common situations in synchronous laser-assisted processing and the corresponding adjustment measures for this device.

[0048] In the diagram: 1. Laser Module: 1-1, Laser control line, 1-2, Laser, 1-3, Laser head; 2. Workpiece; 3. Machining platform; 4. CNC Machine Tool Module: 4-1, Tool, 4-2, Machine tool spindle, 4-3, Machine tool control system, 4-4, Machine tool control line; 5. Industrial computer; 6. Moving device; 7. Detection Module: 7-1, Data transmission line, 7-2, Thermal imager; 8. Connecting device; 9. Pose Adjustment Module: 9-1, Precision XY displacement platform, 9-2, Displacement platform control line. Detailed Implementation

[0049] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0050] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0052] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0053] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0054] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0055] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0056] This invention discloses a device for real-time adjustment of important parameters in synchronous laser-assisted processing, including a processing platform 3, a laser module 1, a CNC machine tool module 4, an industrial computer 5, a moving device 6, a detection module 7, a connecting device 8, and a posture adjustment module 9;

[0057] The laser module 1 includes a laser control line 1-1, a laser 1-2, and a laser head 1-3, and is controlled by an industrial computer 5 to adjust the laser parameters in real time during processing. The CNC machine tool module 4 includes a cutting tool 4-1, a machine tool spindle 4-2, a machine tool control system 4-3, and a machine tool control line 4-4, and is controlled by an industrial computer 5 to adjust the machining parameters in real time during processing. The detection module 7 includes a data transmission line 7-1 and a thermal imager 7-2, which collects and transmits the machining temperature field data to the industrial computer 5 for analysis and processing in real time. The pose adjustment module 9 includes a precision XY displacement platform 9-1 and a displacement platform control line 9-2, and is controlled by an industrial computer 5 to adjust the tool-laser hysteresis distance (the distance by which the leading edge of the tool lags behind the laser spot) in real time during processing.

[0058] In this embodiment, the industrial control computer 5 receives temperature field data observed by the thermal imager 7-2 in real time during processing. Based on preset parameters such as optimal hysteresis distance and material melting point, it detects and compares the real-time temperature field during processing, records and analyzes the real-time temperature values ​​and actual hysteresis distances at various points on the surface of the workpiece 2 in real time, and sends adjustment commands to each module in real time according to preset standards.

[0059] In this embodiment, the thermal imager 7-2 is fixed on the mobile device 6 and placed next to the processing area. The movement speed of the thermal imager 7-2 is the same as that of the cutting tool 4-1, so that the camera of the thermal imager 7-2 is always aligned with the laser heating area, ensuring that the real-time changing processing temperature field does not deviate from the imaging range of the thermal imager 7-2.

[0060] In this embodiment, the pose adjustment module 9 is connected to the machine tool spindle 4-2 via the connecting device 8 to ensure that the laser always irradiates the area to be processed. The laser head 1-3 is mounted on the precision XY displacement platform 9-1 to make real-time precision adjustment of the lag distance.

[0061] In this embodiment, the connecting device 8 and the precision XY displacement platform 9-1 can realize the five-degree-of-freedom motion of the laser head 8, which can translate along three axes and rotate around the YZ axis. This allows for different irradiation angles and heating ranges of the laser beam for end grinding, end milling, and other working conditions.

[0062] In this embodiment, the workpiece 2 can be a hard and brittle material (ceramics, fiber-reinforced composites, cemented carbide, etc.) that is difficult to process by conventional methods, or it can be a material with high requirements for surface quality, processing accuracy, and processing efficiency.

[0063] The processing platform 3 in this embodiment can be a vacuum adsorption platform to quickly fix and disassemble workpieces 2 in block, thin plate, or other shapes. Alternatively, a special fixture can be used to accurately position and clamp workpieces 2 with complex shapes.

[0064] In this embodiment, when milling or grinding is performed, the tool 4-1 can be a milling cutter or a grinding wheel, which is driven by the machine tool spindle 4-2 to achieve different processing requirements.

[0065] A processing method for a device for real-time adjustment of important parameters in synchronous laser-assisted processing, characterized by the following preparatory steps before processing the workpiece:

[0066] Step 1: Set the following standard values ​​in the industrial control computer 5: laser power P (W), laser defocusing amount L 离焦 (mm), tool speed V (r / min), tool feed rate f (m / s), cutting width W 切削 (mm), Material melting point T 熔点 (°C), tool softening temperature T 刀具软化 (°C), Material softening temperature T 软化 (°C). Connect the thermal imager 7-2 to the industrial computer 5, and set the moving speed of the thermal imager 7-2 moving device 6 to the feed speed of the tool 4-2;

[0067] Step 2: Connect the industrial control computer 5 to the laser module 1, CNC machine tool module 4, and posture adjustment module 9, and couple and control them respectively. The priority of each processing parameter adjustment is defined as follows: laser power or hysteresis distance > laser defocusing amount > tool feed speed > spindle speed. That is, when an abnormality is found in the processing temperature field, the high-priority processing parameters are adjusted first. If adjusting the high-priority parameters cannot restore the abnormality or the processing efficiency is reduced, then the next priority parameter is adjusted. Otherwise, only the high-priority processing parameters need to be adjusted.

[0068] Step 3: Position and clamp the workpiece 2 on the processing platform 3. According to the processing requirements, adjust the connecting device 8 and control the precision XY displacement platform 9-1 to move the laser spot to the surface of the workpiece 2 to be heated and softened.

[0069] Taking into account factors such as processing quality, processing efficiency, and adjustment effect, the following real-time adjustment method for processing parameters is formulated to address common abnormal situations during processing:

[0070] (a-1). Thermal imager 7-2 detected the highest temperature T in the temperature field of the area where the material to be removed is located. max Exceeding the material's melting point T 熔点 At that time, the industrial control computer 5 controls the lasers 1-2 to reduce the laser output power;

[0071] (a-2). Thermal imager 7-2 detected the lowest temperature T in the temperature field of the area where the material to be removed. min Below the material softening temperature T 软化 (That is, when the material hardness and strength decrease by about 80% at this temperature), the industrial control computer 5 controls the laser 1-2 to increase the laser output power;

[0072] (b) Thermal imager 7-2 detected the actual hysteresis distance L. 实际滞后 With the optimal lag distance L 最优滞后 When they are no longer equal, the industrial control computer 5 controls the precision XY displacement platform 9-1 to move the laser head 1-3 in real time. 实际滞后 Greater than L 最优滞后 When the lag is small, the movement is in the negative direction of the Y-axis. When the lag is small, the movement direction is reversed. The movement distance is obtained by the difference between the actual lag distance and the optimal lag distance.

[0073] (c-1). Thermal imager 7-2 detected the highest temperature T in the temperature field of the area where the material to be removed. max With the lowest value T min When the difference exceeds the rated value (which depends on the material properties), the material to be removed will soften unevenly, which will easily lead to increased tool wear. The industrial control computer 5 controls the laser 1-2 to increase the positive defocusing amount or decrease the negative defocusing amount.

[0074] (c-2). Thermal imager 7-2 detected the highest temperature value T in the temperature field of the area where the material to be removed. max With the lowest value T min When the difference between the two values ​​is lower than the rated value (which depends on the material properties), the depth of the fully softened material is too shallow and less than the cutting depth of the tool. The industrial control computer 5 controls the laser 1-2 to increase the negative defocusing amount or decrease the positive defocusing amount.

[0075] (d-1). Thermal imager 7-2 detected that the temperature field of the area where the material to be removed is between the highest temperature value T. max With the material softening temperature T 软化 Material width W 被软化材料 Less than the cutting width W 切削 When the material is not fully softened, it will be cut off. The industrial control computer 5 takes into account factors such as adjustment effect and processing efficiency and selects the control module according to priority. The control methods include increasing the laser output power, increasing the laser defocusing amount, or controlling the CNC machine tool module 4 to reduce the feed speed. When adjusting the high priority parameter cannot meet the adjustment requirements, the next priority parameter will be adjusted.

[0076] (d-2). Thermal imager 7-2 detected that the temperature field of the area where the material to be removed is between the highest temperature value T. max With the material softening temperature T 软化 Material width W 被软化材料 Greater than the cutting width W 切削 When the laser output power is doubled or more, the softened material cannot be removed in one go. The industrial control computer 5 takes into account factors such as adjustment effect and processing efficiency and selects the control module according to priority. The control methods include reducing the laser output power, reducing the laser defocusing amount, or controlling the CNC machine tool module 4 to increase the feed speed. When adjusting the high priority parameter cannot meet the adjustment requirements, the next priority parameter is adjusted.

[0077] (e) When the thermal imager 7-2 detects that the temperature field of the area where the material to be removed is under suitable conditions (i.e., conditions abcd above are met), but the leading edge of the tool 4-1 exceeds the tool softening temperature T under the combined effect of the laser beam and cutting heat. 刀具软化 When the hardness or strength of the cutting tool decreases by 20%, the industrial computer 5 controls the CNC machine tool 4-3 to reduce the speed of the machine tool spindle 4-2 to reduce cutting heat.

[0078] (f) When the thermal imager 7-2 detects that the tool 4-1 is about to cut into or out of the workpiece, the industrial control computer 5 controls the laser module 1, the CNC machine tool module 4, and the posture adjustment module 9 to open and close in a timely manner.

[0079] Example 1

[0080] Taking synchronous laser-assisted face grinding as an example, the present invention will be explained in detail. It should be noted that the devices mentioned in this embodiment can be replaced by devices from other manufacturers that can perform the same or similar functions.

[0081] The workpiece 2 is made of block-shaped reaction-sintered silicon carbide (RB-SiC) ceramic. This material has the characteristics of high strength, high hardness and high specific stiffness, and is a typical difficult-to-machine material. The tool 4-1 is a metal-bonded diamond grinding wheel with a diameter of 8 mm and a grit size of 100. The feed rate is 2.5 mm / s, which can timely grind and remove the laser-softened machining area. For this machining material, the laser 1-2 is an FCL 2000 laser, and the laser head 1-3 is an FWC 300 laser head, which can emit a continuous and stable laser beam. The machining power is selected as 120 W. The minimum laser spot diameter formed after passing through the focusing lens is about 1.4 mm. The temperature generated by heating can reach the purpose of material modification and softening, and the width W of the material softening temperature region 被软化材料 is approximately equal to the cutting width W of the grinding wheel 切削 , as shown in Figure 1 . The numerical control machine tool module 4 uses a KMC600SUMT five-axis vertical machining center to process the workpiece 2. The industrial control computer 5 is of the model OEM-12, which can realize the linkage and coupling control of devices such as the laser module 1 and the numerical control machine tool module 4. The thermal imager 7-2 is an NIR series infrared thermal imager, with a maximum temperature measurement of up to 3000 °C. The precision XY-direction displacement platform 9-1 is an electric XY-direction displacement slide KSHY620, with a unidirectional positioning accuracy of within 15 μm, a stroke of 20 mm, and a maximum movement speed of 10 mm / s, which can meet the precise adjustment requirements of the lag distance in real time.

[0082] Before machining, the finite element simulation software ABAQUS is used to simulate the laser irradiation of RB-SiC, establish a simulation model identical to the actual machining conditions, simulate the magnitude and variation law of the temperature field, and calculate the optimal lag distance variation range and variation law according to the softening temperature of the grinding wheel and the softening temperature of RB-SiC, as shown in Figure 2 . The optimal lag distance detection method (the distance between the softening temperature point of the grinding wheel 4-1 and the laser heating center between the grinding wheel and the laser head 1-3) and the actual lag distance detection method (the distance between the leading edge of the grinding wheel and the laser heating center) are stored in the industrial control computer 5. Standard values such as the laser power, laser defocus amount, grinding wheel speed, and material melting point used in the initial machining are set in the industrial control computer 5, and the adjustment priority levels of each parameter are set, that is, laser power or lag distance > laser defocus amount > tool feed rate > spindle speed, ensuring that the industrial control computer can realize the real-time adjustment of each important machining parameter according to the existing program.

[0083] The thermal imager 7-2 is fixed on the moving device 6. The slider in the guide rail is driven by a servo motor to rotate the lead screw, achieving its linear reciprocating motion. The lead screw is fixed to both ends of the guide rail by a lead screw fixing seat. Figure 3 As shown in the diagram. The guide rail can be installed inside or outside the machine tool. The movement speed of the thermal imager 7-2 is set to match the feed speed of the grinding wheel 4-1 to ensure that the temperature field at the center of the machining area is constantly monitored by the temperature detection window of the thermal imager 7-2. Figure 4 As shown in the figure. By controlling the movement of the X-axis displacement platform in the precision XY-axis displacement platform 9-1, the movement path of the laser spot is aligned with the feed direction of the grinding wheel 4-1.

[0084] Laser head 1-3 is fixed to connecting device 8 via precision XY displacement platform 9-1, such as Figure 5 As shown, the laser head 1-3 fixed on the displacement platform 9-1 performs the same feed motion as the grinding wheel 4-1. The connecting device 8 includes a connecting plate and a retaining ring. The connecting plate is connected to the displacement platform, and the retaining ring is fastened to the machine tool spindle 4-2 by bolts. The relative position of the connecting plate and the retaining ring can be adjusted to ensure that the laser beam always irradiates the area to be processed in front of the grinding wheel 4-1, while the laser head can perform XY two-degree-of-freedom motion.

[0085] Multiple thin plate-shaped workpieces 2 are fixed on the vacuum adsorption platform 3. The grinding wheel 4-1 and thermal imager 7-2 are moved to their initial positions, and the industrial control computer controls the opening and closing of each module.

[0086] The industrial control computer 5 is connected to the laser module 1, the CNC machine tool module 4, and the posture adjustment module 9, respectively, and performs linkage coupling control on them. For example... Figure 6 As shown, when laser-synchronized assisted end grinding of RB-SiC encounters the following common situations, the industrial control computer 5 issues corresponding instructions to adjust the processing parameters in real time:

[0087] (a-1). When the thermal imager 7-2 detects that the highest temperature in the temperature field of the RB-SiC area to be removed exceeds the melting point of the material 1410 ℃, the industrial control computer 5 controls the laser 1-2 to reduce the laser output power.

[0088] (a-2). When the thermal imager 7-2 detects that the lowest temperature in the temperature field of the RB-SiC area to be removed is lower than the material softening temperature of 423 ℃, the industrial control computer 5 controls the laser 1-2 to increase the laser output power.

[0089] (b) When the thermal imager 7-2 detects that the actual hysteresis distance and the optimal hysteresis distance in the temperature field of the RB-SiC area to be removed are no longer equal, the industrial control computer 5 controls the precision XY displacement platform 9-1 to move the laser head 1-3 in real time. When the actual hysteresis distance is greater than the optimal hysteresis distance, it moves along the negative Y-axis. When the hysteresis distance is smaller, the movement direction is opposite. The movement distance is obtained by the difference between the actual hysteresis distance and the optimal hysteresis distance.

[0090] (c-1). When the thermal imager 7-2 detects that the temperature gradient between the highest and lowest values ​​in the temperature field of the RB-SiC area to be removed exceeds 900 ℃, the uneven softening of the material to be removed is likely to cause the grinding wheel to wear more severely. The industrial control computer 5 controls the laser 1-2 to increase the positive defocusing amount or decrease the negative defocusing amount.

[0091] (c-2). When the thermal imager 7-2 detects that the temperature gradient between the highest and lowest values ​​in the temperature field of the RB-SiC area to be removed is less than 200 ℃, the depth of the fully softened material is too shallow and less than the cutting depth of the grinding wheel. The industrial control computer 5 controls the laser 1-2 to increase the negative defocusing amount or decrease the positive defocusing amount.

[0092] (d-1). When the thermal imager 7-2 detects that the width of the material between the highest temperature and the softening temperature of RB-SiC in the temperature field of the area to be removed is less than 8 mm of the cutting width, the incompletely softened RB-SiC will be cut off. The industrial control computer 5 comprehensively considers factors such as adjustment effect and processing efficiency and selects the control module according to priority. The adjustment methods include increasing the laser output power by controlling the laser 1-2, increasing the laser defocusing amount, and controlling the CNC machine tool module 4 to reduce the feed speed. When the effect of adjusting the high priority parameter cannot meet the adjustment requirements, the next priority parameter is adjusted.

[0093] (d-2). When the thermal imager 7-2 detects that the width of the material between the highest temperature value and the softening temperature point of RB-SiC in the temperature field of the area to be removed is greater than 16 mm, the softened RB-SiC cannot be removed in one go. The industrial control computer 5 comprehensively considers factors such as adjustment effect and processing efficiency and selects the control module according to priority. The adjustment methods include controlling the laser 1-2 to reduce the laser output power, reduce the laser defocusing amount, and the CNC machine tool module 4 to increase the feed speed. When the effect of adjusting the high priority parameter cannot meet the adjustment requirements, the next priority parameter is adjusted.

[0094] (e). Thermal imager 7-2 detected that the temperature field in the RB-SiC region to be removed was under suitable conditions (i.e., T). max <1410℃, T min >423 ℃, (T max - T min )∈200 ℃~900 ℃, 16 mm>W被软化RB-SiC ≥8 mm, L 实际滞后 = L 最优滞后 When the diamond grinding wheel 4-1 exceeds the softening temperature of 2800 ℃ due to the combined effect of the laser beam and cutting heat, the industrial control computer 5 controls the CNC machine tool module 4 to reduce the speed of the machine tool spindle 4-2 to reduce cutting heat.

[0095] (f) When the thermal imager 7-2 detects that the grinding wheel 4-1 is about to cut into or out of the RB-SiC workpiece, the industrial control computer 5 controls the laser module 1, the CNC machine tool module 4, and the posture adjustment module 9 to open and close in a timely manner.

[0096] By adjusting key parameters in synchronous laser-assisted processing in real time, high-quality, high-efficiency, and high-precision processing of difficult-to-machine materials can be achieved.

[0097] This invention enables real-time adjustment of key processing parameters based on the processing temperature field, avoiding the use of unreasonable preset parameters during processing. It ensures that the material with optimal surface modification can always be removed without the tool's performance degrading due to overheating. This reduces the adverse effects of fixed parameters on workpiece processing quality when facing changes in working conditions. At the same time, the adaptive adjustment of key parameters such as laser power and machine tool spindle speed using priority adjustment methods can make the use of the equipment more reasonable and improve energy utilization.

[0098] The specific embodiments of the present invention have been described above with reference to the accompanying drawings. However, these descriptions should not be construed as limiting the scope of the present invention. The scope of protection of the present invention is defined by the appended claims. Any modifications based on the claims of the present invention are within the scope of protection of the present invention.

Claims

1. A method for real-time adjustment of important parameters in synchronous laser-assisted processing, characterized in that: The device used includes a processing platform (3), a laser module (1), a CNC machine tool module (4), an industrial computer (5), a moving device (6), a detection module (7), a connecting device (8), and a posture adjustment module (9). The laser module (1) includes a laser control line (1-1), a laser (1-2), and a laser head (1-3). The laser module (1) is connected to an industrial computer (5) and is used to execute the instructions issued by the industrial computer (5) during processing and to adjust the laser parameters in real time. The CNC machine tool module (4) includes a cutting tool (4-1), a machine tool spindle (4-2), a machine tool control system (4-3), and a machine tool control line (4-4). The CNC machine tool module (4) is connected to an industrial computer (5) and is used to execute the instructions issued by the industrial computer (5) during processing and to adjust the machining parameters in real time. The detection module (7) includes a data transmission line (7-1) and a thermal imager (7-2). The detection module (7) is connected to the industrial computer (5) and is used to detect and collect processing temperature field data in real time during processing and transmit the collected data to the industrial computer (5). The pose adjustment module (9) includes a precision XY displacement platform (9-1) and a displacement platform control line (9-2). The pose adjustment module (9) is connected to the industrial computer (5) and is used to execute the instructions issued by the industrial computer (5) during processing and to adjust the tool-laser hysteresis distance in real time. The posture adjustment module (9) and the CNC machine tool module (4) are connected by the connecting device (8); The detection module (7) is connected to the moving device (6), and the moving device (6) is connected to the industrial control computer (5). The moving device (6) is used to execute the instructions issued by the industrial control computer (5) during processing and adjust the position of the detection module (7). The specific processing method is as follows: The following preparatory steps are included before machining the workpiece: Step 1: Set the following standard values ​​in the industrial control computer (5): laser power P (W), laser defocusing amount L 离焦 (mm), tool speed V (r / min), tool feed rate f (m / s), cutting width W 切削 (mm), Material melting point T 熔点 (°C), tool softening temperature T 刀具软化 (°C), Material softening temperature T 软化 (°C); Connect the thermal imager (7-2) to the industrial computer (5), and set the moving speed of the thermal imager (7-2) to the feed speed of the tool (4-2); Step 2: Connect the industrial computer (5) to the laser module (1), the CNC machine tool module (4), and the pose adjustment module (9) and couple them to control them respectively. Set the priority of processing parameter adjustment. When an abnormality is found in the processing temperature field, the high priority processing parameters are adjusted first. If adjusting the high priority parameters cannot restore the abnormality or the processing efficiency is reduced, the next priority parameter is adjusted. Otherwise, only the high priority processing parameters are adjusted. Step 3: Position and clamp the workpiece (2) on the processing platform (3). According to the processing requirements, adjust the connecting device (8) and control the precision XY displacement platform (9-1) to move the laser spot to the surface of the workpiece (2) to be heated and softened. The following steps are included in the machining of the workpiece: Taking into account factors such as processing quality, processing efficiency, and adjustment effectiveness, the following real-time adjustment methods for processing parameters are formulated to address common abnormal situations during processing: (a-1). The thermal imager (7-2) detected the highest temperature T in the temperature field of the area where the material to be removed is located. max Exceeding the material's melting point T 熔点 At that time, the industrial control computer (5) controls the laser (1-2) to reduce the laser output power; (a-2). The thermal imager (7-2) detected the lowest temperature T in the temperature field of the area where the material to be removed. min Below the material softening temperature T 软化 At the same time, the industrial control computer (5) controls the laser (1-2) to increase the laser output power; (b). The thermal imager (7-2) detected the actual hysteresis distance L. 实际滞后 With the optimal lag distance L 最优滞后 When they are no longer equal, the industrial control computer (5) controls the precision XY displacement platform (9-1) to drive the laser head (1-3) to move in real time. 实际滞后 Greater than L 最优滞后 When the lag is small, the movement is in the negative direction of the Y-axis. When the lag is small, the movement direction is reversed. The movement distance is obtained by the difference between the actual lag distance and the optimal lag distance. (c-1). The thermal imager (7-2) detected the highest temperature T in the temperature field of the area where the material to be removed is located. max With the lowest value T min When the difference exceeds the rated value, the material to be removed will soften unevenly, which will easily lead to increased tool wear. The industrial control computer (5) controls the laser (1-2) to increase the positive defocusing amount or decrease the negative defocusing amount. (c-2). The thermal imager (7-2) detected the highest temperature T in the temperature field of the area where the material to be removed is located. max With the lowest value T min When the difference between the two values ​​is lower than the rated value, the depth of the fully softened material is too shallow and less than the cutting depth of the tool. The industrial control computer (5) controls the laser (1-2) to increase the negative defocusing amount or decrease the positive defocusing amount. (d-1). The thermal imager (7-2) detected that the temperature field of the area where the material to be removed is between the highest temperature value T. max With the material softening temperature T 软化 Material width W 被软化材料 Less than the cutting width W 切削 When the material that is not fully softened is cut off, the industrial control computer (5) comprehensively considers the adjustment effect and processing efficiency factors and selects the control module according to priority. The control methods include increasing the laser output power, increasing the laser defocusing amount, or controlling the CNC machine tool module (4) to reduce the feed speed. When adjusting the high priority parameter cannot meet the adjustment requirements, the next priority parameter is adjusted. (d-2). The thermal imager (7-2) detected that the temperature field in the area of ​​the material to be removed was between the highest temperature value T. max With the material softening temperature T 软化 Material width W 被软化材料 Greater than the cutting width W 切削 When the amount of softened material is twice or more, it cannot be removed in one go. The industrial control computer (5) comprehensively considers the adjustment effect and processing efficiency factors and selects the control module according to priority. The control methods include reducing the laser output power, reducing the laser defocusing amount, or controlling the CNC machine tool module (4) to increase the feed speed. When adjusting the high priority parameter cannot meet the adjustment requirements, the next priority parameter is adjusted. (e) When the thermal imager (7-2) detects that the temperature field of the area to be removed is under suitable conditions, but the cutting edge (4-1) exceeds the tool softening temperature T under the combined effect of the laser beam and cutting heat. 刀具软化 At that time, the industrial control computer (5) controls the CNC machine tool (4-3) to reduce the speed of the machine tool spindle (4-2) and reduce the cutting heat. The suitable conditions are the abcd conditions. (f). When the thermal imager (7-2) detects that the cutting tool (4-1) is about to cut into or out of the workpiece, the industrial control computer (5) controls the laser module (1), the CNC machine tool module (4), and the posture adjustment module (9) to open and close in a timely manner; In step two, the priority of adjusting each processing parameter is as follows: laser power or hysteresis distance > laser defocusing amount > tool feed speed > spindle speed.

2. The method according to claim 1, characterized in that: The industrial control computer (5) receives the temperature field data observed by the thermal imager (7-2) in real time during processing, and detects and evaluates the real-time temperature field during processing according to the preset optimal hysteresis distance and material melting point parameters. It records and analyzes the real-time temperature values ​​and actual hysteresis distances at various points on the surface of the workpiece (2) in real time, and sends adjustment instructions to each module in real time according to the preset adjustment method. The optimal hysteresis distance refers to the distance between the softening temperature point of the tool (4-1) and the center point of the laser spot in the laser irradiation temperature field along the feed direction of the tool (4-1). Maintaining the optimal hysteresis distance can ensure that the material with the best surface modification can always be removed without the tool (4-1) being heated and softened, thus reducing its performance.

3. The method according to claim 1, characterized in that: The thermal imager (7-2) is fixed on the mobile device (6) and placed next to the processing area. The movement speed of the thermal imager (7-2) is the same as that of the cutting tool (4-1), so that the camera of the thermal imager (7-2) is always aligned with the laser heating area, ensuring that the real-time changing processing temperature field does not deviate from the imaging range of the thermal imager (7-2).

4. The method according to claim 1, characterized in that: The pose adjustment module (9) is connected to the machine tool spindle (4-2) through the connecting device (8), and the laser head (1-3) is installed on the precision XY displacement platform (9-1) to make real-time precision adjustment of the lag distance.

5. The method according to claim 1, characterized in that: The connecting device (8) and the precision XY displacement platform (9-1) can realize the five-degree-of-freedom motion of the laser head (8) along the three axes of translation and around the YZ axis, and can change the different irradiation angle and heating range of the laser beam for end grinding and end milling conditions.

6. The method according to claim 1, characterized in that: The materials of the workpiece (2) include hard and brittle materials that are difficult to process by traditional processing methods, as well as materials with preset requirements for surface quality and processing efficiency.

7. The method according to claim 1, characterized in that: The processing platform (3) can be used to install workpieces by using a vacuum adsorption platform or a special fixture. By using a vacuum adsorption platform, block-shaped and thin-plate-shaped workpieces (2) can be quickly fixed and disassembled. By using a special fixture, workpieces (2) with complex shapes can be accurately positioned and clamped.

8. The method according to claim 1, characterized in that: Cutting tools (4-1) are selected according to specific machining requirements, including milling cutters and grinding wheels.

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