Water-jet guided laser processing system for sheet material

Abstract

The invention provides a water-jet guided laser processing system for sheet materials. The water-jet guided laser processing system comprises a laser; a spectroscope; a focus lens; a water guide processing head; the to-be-machined thin plate is subjected to water-guided laser cutting machining through water jet; the array porous supporting thin plate is attached to the bottom of the to-be-machined thin plate from the bottom direction, and an integrated supporting structure is formed for the to-be-machined thin plate; the first clamp is used for clamping the thin plate to be machined and the array porous supporting thin plate from the upper surface of the thin plate to be machined and the lower surface of the array porous supporting thin plate; and the drainage device is positioned below the array porous supporting thin plate. Thin plate deformation control and water flow control of a water guide laser system are achieved by optimizing the thin plate supporting design, the direction and strength of water flow are accurately controlled, interference of water flow to the thin plate is reduced, the cooling effect and the laser transmission mode are improved, deformation and displacement of thin plate materials are effectively restrained, and the machining precision, stability and surface quality are improved. The problems that in the prior art, thin plate machining precision is poor, and the surface is unstable are solved.

Description

Technical Field

[0001] The invention relates to the technical field of water-conducting laser processing, and in particular to a water-conducting laser processing system for thin plate materials. Background Art

[0002] When the existing water-guided laser processes thin plate materials, due to the diffusion effect of the water flow, the thin plate materials are prone to displacement or deformation during the processing, resulting in reduced processing accuracy. In particular, during the thin plate processing, due to the uneven effect of the water flow, the thin plate is subjected to unbalanced forces, which in turn causes slight movement or warping, affecting the stability of the processing. This deformation caused by the water flow not only causes irregular cutting lines and dimensional deviations in the water-guided processing, but also causes thermal stress cracks on the processed surface.

[0003] Through long-term testing and research, the inventors found that the main reason for the above-mentioned problems is that the diffusion effect of the water flow is not effectively controlled, and the processing system lacks the ability to dynamically adapt to the thin plate material, cannot accurately compensate for the deformation or displacement caused by the water flow, and cannot meet the needs of high-precision processing of thin plate materials, resulting in poor precision, poor stability and unstable surface quality of thin plate processing.

[0004] In addition, the deformation and warping of thin plate materials cause the incision deviation of water jet processing, resulting in large deviations in the incision position size and defects, further causing problems of unstable accuracy and surface quality. Summary of the invention

[0005] The purpose of the present invention is to provide a water-guided laser processing system for thin plate materials, optimize the thin plate support, realize water flow control, avoid defects such as deformation, displacement and warping caused by water flow, improve processing accuracy and surface quality, and reduce the defect rate in Jiangdu.

[0006] According to a first aspect of the present invention, a water-conducting laser processing system for thin plate materials is provided, comprising:

[0007] Lasers;

[0008] Beam splitter;

[0009] Focusing lens;

[0010] A water-guided machining head, used for ejecting a machining water jet by coupling a light beam with a water beam;

[0011] The thin plate to be processed, located below the water-guided processing head, is subjected to water-guided laser cutting processing by the water jet;

[0012] An array of porous support sheets is attached to the bottom of the sheet to be processed from the bottom direction to form an integrated support structure for the sheet to be processed;

[0013] A first clamp is used to clamp the thin plate to be processed and the array porous support plate from the upper surface of the thin plate to be processed and the lower surface of the array porous support plate; and

[0014] A drainage device is located below the array porous support sheet.

[0015] In a further embodiment, the hole shape of the array porous support plate is circular or regular hexagonal.

[0016] In a further embodiment, the diameter of the hole is set to 1-5 mm.

[0017] In a further embodiment, the array porous support thin plate is a thin plate supported by a material having a thermal expansion coefficient matching that of the thin plate to be processed.

[0018] In a further embodiment, the first fixture clamps the thin plate to be processed and the array porous support plate in a multi-point positioning manner.

[0019] In a further embodiment, the water-conducting laser processing system is provided with a CCD camera for capturing images of the cutting area at a set sampling frequency to obtain an image of the processing area.

[0020] In a further embodiment, the sampling frequency of the CCD camera is set to capture one frame of image every time the water-guided machining head moves 0.1 mm.

[0021] In a further embodiment, the control system of the water-guided laser processing system is connected to a CCD camera, and an angle deviation between the incision and the vertical direction is calculated based on image processing according to the image of the processing area as the verticality deviation of the incision.

[0022] In a further embodiment, the control system establishes a water-guided machining state space prediction model based on a water jet impact force model, a thin plate thermal deformation model, and a laser energy absorption and transfer model, with laser power, water jet pressure, and cutting speed as input vectors and a verticality deviation of the cut as an output vector;

[0023] Based on the process parameters of each time step obtained by actual measurement and the verticality deviation of the cut, the coefficient matrix in the state space model is determined by a parameter identification method;

[0024] The objective function is to minimize the sum of squares of the verticality deviation of the incision in the predicted time domain in the future, and the process parameter constraints are determined. The optimization solution is performed to obtain the input control sequence that minimizes the objective function while satisfying the process parameter constraints, and the compensation amount of the water-conducting laser processing process parameters is obtained, thereby ensuring the verticality of the processed incision.

[0025] In a further embodiment, the calculating the angle deviation between the incision and the vertical direction based on the image processing according to the processing area image includes:

[0026] Preprocess and remove noise from the processed area image and convert it into a grayscale image;

[0027] The edge of the grayscale image is extracted through edge detection, and the pixel points of the cut edge contour are obtained;

[0028] Perform straight line fitting on the pixel points of the edge contour of the incision and calculate the slope and intercept of the fitting line to determine the shape and direction of the incision;

[0029] The verticality deviation of the cut is calculated based on the angle between the fitting straight line and the ideal vertical direction.

[0030] The water-guided laser processing system for thin plate materials of the present invention has the following significant advantages:

[0031] In view of the processing quality defects caused by the deformation, warping and movement of thin plate materials in the water-guided laser processing process in the prior art, the water-guided laser processing system for thin plate materials proposed by the present invention sets an array of porous support thin plates at the bottom of the thin plate to be processed, and fits the thin plate to be processed from the bottom direction to form an integrated support structure, so as to prevent the thin plate from being deformed due to the impact force of the water jet and other factors during the processing process, reduce the dimensional deviation, cracks and thermal deformation caused by the deformation of the thin plate, and ensure the processing accuracy. At the same time, the CCD camera is further combined to perform real-time image acquisition and processing of the cutting position, obtain the incision verticality deviation, and obtain the compensation amount of the water-guided laser processing process parameters through the water-guided processing state space prediction model, so as to ensure the verticality of the processing incision, adapt to the changes in the actual cutting process, correct the deviation in time, improve the stability of the processing process, and improve the processing accuracy.

[0032] It should be understood that all combinations of the aforementioned concepts and the additional concepts described in more detail below can be considered as part of the inventive subject matter of the present disclosure as long as such concepts are not mutually inconsistent. In addition, all combinations of the claimed subject matter are considered as part of the inventive subject matter of the present disclosure.

[0033] The foregoing and other aspects, embodiments and features of the present invention can be more fully understood from the following description in conjunction with the accompanying drawings. Other additional aspects of the present invention, such as the features and / or beneficial effects of the exemplary embodiments, will be apparent from the following description or learned from the practice of the specific embodiments according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings are not intended to be drawn to scale. In the accompanying drawings, each identical or nearly identical component shown in each figure may be represented by the same reference numeral. For clarity, not every component is labeled in each figure. Embodiments of various aspects of the present invention will now be described by way of example and with reference to the accompanying drawings.

[0035] Figure 1 4 is a schematic diagram of a water-guided laser processing system for thin plate materials according to an embodiment of the present invention.

[0036] Figure 2 Schematic diagram of an array porous support plate of a water-guided laser processing system for thin plate materials according to an embodiment of the present invention.

[0037] Figure 3 Schematic diagram of a clamping method of a water-guided laser processing system for thin plate materials according to an embodiment of the present invention.

[0038] Figure 4 It is a flowchart of algorithm processing of a state space model of a water-guided laser processing system for thin plate materials according to an embodiment of the present invention.

[0039] Figure 5 and Figure 6 The schematic diagrams respectively show the processing results of the stainless steel sheet by the water-conducting laser processing system according to the present invention and the processing results by the traditional processing technology. DETAILED DESCRIPTION

[0040] In order to better understand the technical content of the present invention, specific embodiments are given and described as follows in conjunction with the accompanying drawings.

[0041] Various aspects of the present invention are described in this disclosure with reference to the accompanying drawings, in which many illustrative embodiments are shown. The embodiments of the present disclosure are not necessarily intended to include all aspects of the present invention. It should be understood that the various concepts and embodiments introduced above, as well as those described in more detail below, can be implemented in any of many ways, because the concepts and embodiments disclosed by the present invention are not limited to any implementation. In addition, some aspects disclosed by the present invention can be used alone or in any appropriate combination with other aspects disclosed by the present invention.

[0042] {Example 1}

[0043] Combination Figure 1-3 The water-conducting laser processing system for thin plate materials of the illustrated embodiment includes a laser 1, a beam splitter 2, a focusing lens 3, a water-conducting processing head 4, a first fixture 6, a drainage device 50 and a control system.

[0044] Combination Figure 1As shown, the water-conducting machining head 4 couples the light beam with the water beam to emit a machining water jet 5. The thin plate 10 to be machined is clamped by the first clamp 6 and is located below the water-conducting machining head 4, and the water jet 5 performs water-conducting laser cutting.

[0045] Combination Figure 1 , Figure 2 As shown, the array porous support sheet 20 is attached to the bottom of the thin sheet 10 to be processed from the bottom direction to form an integrated support structure for the thin sheet 10 to be processed.

[0046] The first clamp 6 clamps the thin plate 10 to be processed and the array porous support plate 20 from the upper surface of the thin plate 10 to be processed and the lower surface of the array porous support plate 20 .

[0047] It is particularly preferred that the first fixture 6 clamps the thin plate 10 to be processed and the array porous support thin plate 20 in a multi-point positioning manner. Figure 2 , Figure 3 As shown, for the thin plate 10 to be processed, multi-point positioning and clamping are performed from the four corner edge positions.

[0048] Combination Figure 1 As shown, a drainage device 50 is also provided below the array porous support sheet 20 for receiving the water flow of the water guide processing and discharging it through the guide design.

[0049] As an optional embodiment, the hole shape of the array porous support thin plate 20 is circular or regular hexagonal. The regular hexagonal hole shape is used as an example for description in conjunction with the figure.

[0050] The diameter of the hole is set to 1-5 mm.

[0051] In a particularly preferred embodiment, the array porous support plate 20 is supported by a material that matches the thermal expansion coefficient of the thin plate 10 to be processed, and in particular, is supported by a supporting material with the same thermal expansion coefficient. For example, for aluminum alloys, stainless steel, ceramic materials, composite fiber-reinforced metal materials (such as CFRP thin plates), etc., corresponding materials with similar or identical thermal expansion coefficients can be used for support.

[0052] In combination with the above embodiments, the design of the present invention solves the problem of thin plate displacement and deformation caused by water flow diffusion during water-guided laser processing of thin plate materials, thereby affecting the processing accuracy and surface quality. Since the prior art fails to effectively control the diffusion of water flow, the thin plate material is subjected to uneven force during the processing, causing displacement or warping, which is particularly obvious in high-precision processing. In addition, the prior art has insufficient control over thermal stress and deformation, and lacks an effective dynamic compensation mechanism, resulting in instability during the processing. To this end, the present invention optimizes water flow control and improves thin plate deformation through a thin plate support design, which can accurately control the direction and intensity of the water flow, reduce the impact of water flow diffusion, and at the same time improve the cooling effect and prevent deformation caused by thermal stress, thereby solving the problems of poor thin plate processing accuracy, poor stability and unstable surface quality in the prior art.

[0053] {Example 2}

[0054] In this embodiment, combined with Figure 1 As shown, the water-guided laser processing system is provided with a CCD camera 8 for capturing images of the cutting area at a set sampling frequency to obtain an image of the processing area.

[0055] The sampling frequency of the CCD camera 8 is set to capture one frame of image every time the water-guided machining head 4 moves 0.1 mm.

[0056] The control system of the water-guided laser processing system is connected to the CCD camera 8, and the angle deviation between the incision and the vertical direction is calculated based on image processing according to the image of the processing area as the verticality deviation of the incision.

[0057] As an optional embodiment, the calculating the angle deviation between the incision and the vertical direction based on the image processing according to the processing area image includes:

[0058] Preprocess and remove noise from the processed area image and convert it into a grayscale image;

[0059] The edge of the grayscale image is extracted through edge detection, and the pixel points of the cut edge contour are obtained;

[0060] Perform straight line fitting on the pixel points of the edge contour of the incision and calculate the slope and intercept of the fitting line to determine the shape and direction of the incision;

[0061] The verticality deviation of the cut is calculated based on the angle between the fitting straight line and the ideal vertical direction.

[0062] In this embodiment, a high-resolution CCD camera captures and images the cutting area at a set sampling frequency (eg, one frame of image is captured every 0.1 mm of movement) to obtain a digital image signal.

[0063] The captured digital image is transmitted to the image processing module in the control system through a high-speed communication interface. Image preprocessing can use existing noise reduction algorithms to perform image denoising and then grayscale conversion operations. Denoising can use methods such as median filtering to remove interference factors such as salt and pepper noise and Gaussian noise in the image.

[0064] Then, the color image is converted into a grayscale image through grayscale processing, which reduces the amount of data and highlights the edge information of the image, preparing for subsequent edge detection and shape analysis.

[0065] Furthermore, the Canny edge detection algorithm is used to process the preprocessed grayscale image. First, the image is smoothed by Gaussian filtering to reduce the influence of noise on edge detection, and then the gradient amplitude and direction of the image are calculated. The pixel points of the incision edge are extracted through non-maximum suppression and double threshold detection.

[0066] For example, the kernel size of the Gaussian filter can be selected according to the image noise level. In this example, 3*3 pixels are selected. The high and low threshold settings of the dual threshold are adjusted according to the contrast and edge strength of the image. The low threshold can be set between 20-50 grayscale values, and the high threshold can be set between 50-100 grayscale values ​​to ensure that the incision edge can be accurately detected while reducing false detection and missed detection.

[0067] After extracting the edge pixel points of the incision, the least squares method is used to fit the edge points to a straight line. The approximate shape and direction of the incision are determined by calculating the slope and intercept of the fitted straight line. Then, the verticality deviation of the incision is calculated based on the angle between the fitted straight line and the ideal vertical direction (such as the y-axis direction of the image coordinate system). For example, for a fitted straight line y=fx+b, its slope f reflects the degree of inclination of the straight line. The angle between the straight line and the x-axis is obtained by calculating arctan(f), and then the angle deviation from the vertical direction is calculated, which is the verticality deviation of the incision.

[0068] As an optional embodiment, the control system establishes a water-guided machining state space prediction model based on the water jet impact force model, the thin plate thermal deformation model, and the laser energy absorption and transfer model, with the laser power, water jet pressure, and cutting speed as input vectors and the verticality deviation of the cut as the output vector;

[0069] Based on the process parameters of each time step obtained by actual measurement and the verticality deviation of the cut, the coefficient matrix in the state space model is determined by a parameter identification method;

[0070] The objective function is to minimize the sum of squares of the verticality deviation of the incision in the predicted time domain in the future, and the process parameter constraints are determined. The optimization solution is performed to obtain the input control sequence that minimizes the objective function while satisfying the process parameter constraints, and the compensation amount of the water-conducting laser processing process parameters is obtained, thereby ensuring the verticality of the processed incision.

[0071] Combination Figure 4 As shown, in this embodiment, by combining the thermal deformation model of the thin plate, the water jet impact force model, the laser energy absorption and transfer model and the motion model of the water-guided processing head, a state space model of water-guided laser cutting processing is constructed, and their mutual influence on the verticality of the cut is comprehensively considered. By solving an optimization problem, the compensation amount of the process parameters required to keep the verticality of the cut within the target range in the future time step (such as the next 10-100ms) is calculated. The objective function of the optimization problem is selected to minimize the deviation of the verticality of the cut, and the constraints include the range of values ​​of process parameters such as laser power, water jet pressure, cutting speed, and the motion limit of the water-guided processing head.

[0072] As an example, the construction of a thin plate thermal deformation model includes the following steps:

[0073] Based on Fourier's law of heat conduction, for thin plate materials, the heat conduction equation is obtained as follows:

[0074]

[0075] Among them, ρ represents the density of the thin plate material, c represents the specific heat capacity, T represents the temperature field, t represents the time, k represents the thermal conductivity, and q represents the heat source term, that is, the laser energy input;

[0076] In the case of a two-dimensional thin plate (assuming that the temperature is uniform in the thickness direction of the thin plate), the heat conduction equation is further equivalent to:

[0077]

[0078] The equation is discretely solved by the finite difference method or the finite element method to obtain the temperature distribution T(x, y, t) of the thin plate at different positions and times;

[0079] Furthermore, according to the thermal expansion coefficient α of the thin plate material, the relationship between the thermal deformation ΔL and the temperature change ΔT is obtained as follows:

[0080] ΔL=αLΔT;

[0081] Where L is the original length before deformation;

[0082] For any point (x, y) on the thin plate, the thermal deformation in the x and y directions is expressed as:

[0083] Δx=αxΔT(x, y, t), Δy=αyΔT(x, y, t);

[0084] Thus, the shape change of the thin plate caused by thermal deformation is obtained.

[0085] As an example, the water jet impact force construction includes the following steps:

[0086] The momentum equation of the water jet is established and expressed as:

[0087]

[0088] Among them, ρ w represents the density of water, represents the water jet velocity vector, p represents the pressure, μ w Represents the dynamic viscosity of water; by solving the momentum equation, the velocity and pressure distribution of the water jet at different positions are obtained;

[0089] When the water jet impacts the thin plate material, according to the momentum theorem, the impact force is expressed as:

[0090]

[0091] Where A is the contact area between the water jet and the thin plate, is the normal vector of the plate surface.

[0092] Furthermore, the impact force of the water jet at different positions on the thin plate surface is integrated to obtain the total water jet impact force and its moment, so as to analyze its influence on the deformation of the thin plate and the verticality of the cut.

[0093] As an example, the construction of the laser energy absorption and transfer model includes the following steps:

[0094] Regarding the absorption of laser energy by thin plate materials, according to the Beer-Lambert law, the intensity of the laser in the thin plate is expressed as:

[0095]

[0096] Among them, I 0 is the incident laser intensity, α m is the absorption coefficient of the thin plate material to the laser, and z is the coordinate in the thickness direction of the thin plate. The energy Q absorbed by the laser in the thickness direction of the thin plate is calculated by integration:

[0097]

[0098] Where, d is the thickness of the sheet;

[0099] Part of the absorbed laser energy is used to melt and vaporize the material, and part is transferred in the thin plate in the form of heat conduction; according to the melting latent heat L of the thin plate material m and latent heat of vaporization L υ , calculate the energy required to melt and vaporize the material, and the remaining energy causes the temperature of the thin plate to increase, further affecting the thermal deformation.

[0100] The construction of the motion model of a water-guided machining head as an example includes the following steps:

[0101] According to Newton's second law, the motion equation of the water-guided machining head motion platform is constructed:

[0102]

[0103] Where m is the mass of the machining head motion platform and load, is the displacement vector of the worktable, F m is the driving force of the platform motor, is the friction force, It is the cutting force, that is, the impact force of the water jet.

[0104] Furthermore, by solving the equations, the motion trajectory, velocity and acceleration of the workbench are obtained.

[0105] Combination Figure 4 As shown, on the basis of establishing the model, the key variables in the above model are combined into a state vector:

[0106]

[0107] It includes the temperature field of the thin plate, the impact force of the water jet, the displacement of the workbench, the water jet velocity and other related variables. The input vector includes the laser power P, the water jet pressure p w , cutting speed c Equal process parameters, output vector Indicates the verticality deviation of the cut.

[0108] The state space model is thus established:

[0109]

[0110] Among them, A, B, and C are coefficient matrices, and are the process noise and measurement noise vectors respectively, and k represents the time step index.

[0111] By systematically identifying the coefficient matrix of the established multi-factor correlation model, the coefficient matrices A, B, and C in the state space model can be determined by using the least squares parameter identification method through experimental data. For example, under different combinations of laser power, water jet pressure, and cutting speed, the temperature change of the thin plate, the impact force of the water jet, the movement of the worktable, and the verticality deviation data of the cut are measured, and then the model parameters are fitted based on these data, so that the model can accurately describe the actual cutting process.

[0112] Set the prediction time domain N p and control time domain N u The prediction horizon refers to the number of time steps that the algorithm predicts the future system behavior. For example, if N p =10, that is, predicting the system state for the next 10 time steps. The control time domain refers to the number of time steps of future control input changes determined at the current moment, such as N u =5, indicating the change strategy of the control inputs such as laser power and water jet pressure in the next five time steps.

[0113] Furthermore, by solving the optimization problem, the optimal control input sequence is obtained and the compensation amount of the process parameters is determined.

[0114] As an optional embodiment, the objective function is set to minimize the sum of squares of the verticality deviations of the cuts in a future period of time (prediction time domain), that is:

[0115]

[0116] in, is the reference cut verticality (usually set to 0), Q k is a weight matrix, which is used to adjust the weights of deviations at different time steps. The closer to the current moment, the larger the weight, so as to pay more attention to the correction of recent deviations.

[0117] At the same time, considering the change range of the control input, a penalty term is added:

[0118]

[0119] Among them, R k The weight matrix for controlling input changes is used to prevent the control input from fluctuating violently.

[0120] The constraints of process parameters are further determined, including the constraints of laser power, water jet pressure, and cutting speed.

[0121] For example, the laser power P min ≤P≤P max ;

[0122] Water jet pressure p w，min ≤p w ≤pw,max ;

[0123] Cutting speed c,min ≤υ c ≤υ c，max .

[0124] Platform motion constraints: including the platform's maximum acceleration a max , maximum speedυ max wait, υ c，k ≤υ max .

[0125] Then, an optimization algorithm such as the quadratic programming (QP) algorithm or the interior point method is used to solve the above optimization problem. Under the constraints, the control input sequence that minimizes the objective function is found. in That is, the compensation amount of process parameters such as laser power, water jet pressure and cutting speed that need to be adjusted at the current moment.

[0126] For example, when solving using the interior point method, the optimization problem is first converted into a standard form, and then a series of linear equations and linear programming problems are solved iteratively to gradually approach the optimal solution. In each iteration, the current solution is judged to be within the feasible region based on its position. If it is on the boundary, special processing is performed to maintain the feasibility of the iteration until the convergence condition is met and the optimal control input sequence is obtained.

[0127] As an optional embodiment, the parameters of the prediction model may be further regularly modified according to the difference between the measurement data and the actual cutting process to achieve feedback and model modification.

[0128] As an optional embodiment, at each time step, the state vector in the prediction model is corrected using the measured values ​​of the actual cut verticality deviation and other related state variables measured by a laser interferometer and a machine vision system.

[0129] A state estimation method such as Kalman filtering can be used to update the state vector based on the difference between the measured value and the predicted value:

[0130]

[0131] in, is the predicted state vector based on the previous moment: is the predicted output vector based on the previous moment, K k is the Kalman gain matrix.

[0132] The Kalman gain matrix is ​​obtained by solving the Riccati equation. It is determined based on the covariance matrix of system noise and measurement noise so that the mean square error of state estimation is minimized.

[0133] According to the difference between the measured data and the actual cutting process, the parameters of the prediction model can be corrected regularly. For example, if it is found that the actual cut verticality deviation is significantly different from the model prediction value, check the possible error sources in the model, such as whether the thermal conductivity parameters in the thermal deformation model are accurate, whether the water jet velocity distribution assumption in the water jet impact force model is reasonable, etc. Through experimental data or simulation analysis, these parameters are adjusted so that the model can better adapt to the changes in the actual cutting process. For example, if the thermal conductivity parameters are found to be inaccurate, the thermal conductivity can be re-measured by conducting heat conduction experiments on the thin plate material at different temperatures, and the thermal conductivity parameters in the thermal deformation model can be updated to improve the accuracy of the model prediction.

[0134] {Example 3}

[0135] Combination Figure 5 , Figure 6 As shown, according to the above-mentioned embodiment 1 of the present invention, a water-guided laser processing system with optimized support for thin plate materials is designed. By optimizing the thin plate support design, thin plate deformation control and water flow control of the water-guided laser system are achieved, the direction and intensity of the water flow are accurately controlled, the interference of the water flow on the thin plate is reduced, the cooling effect and the laser transmission method are improved, the deformation and displacement of the thin plate material are effectively suppressed, and the problems of poor thin plate processing accuracy and surface instability in the prior art are solved.

[0136] exist Figure 6 The processing results show that the edge transition of the cut is not smooth, and there are burrs and gaps. Figure 5 As shown, the incision edge transition of the design and processing proposed by the present invention is smooth and has no defects such as chipping, burrs, cracks, and notches. It can be seen that the water-guided laser processing system for thin plate materials designed by the present invention can significantly improve the processing accuracy, stability and surface quality.

[0137] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. A person with ordinary knowledge in the technical field to which the present invention belongs may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the definition of the claims.

Claims

1. A water-guided laser processing system for thin plate materials, characterized in that: include: Laser (1); Spectroscope (2); Focusing lens (3); A water-guided processing head (4) is used to eject a processing water jet (5) by coupling a light beam with a water beam; The thin plate (10) to be processed, which is located below the water-conducting processing head (4), is subjected to water-conducting laser cutting processing via the water jet (5); An array of porous support thin plates (20) is attached to the bottom of the thin plate (10) to be processed from the bottom direction to form an integrated support structure for the thin plate (10) to be processed; A first clamp (6) is used to clamp the thin plate to be processed (10) and the array porous support plate (20) from the upper surface of the thin plate to be processed (10) and the lower surface of the array porous support plate (20); as well as A drainage device (50) is located below the array porous support sheet (20).

2. The water-conducting laser processing system for thin plate materials according to claim 1, characterized in that: The hole shape of the array porous support thin plate (20) is circular or regular hexagonal.

3. The water-conducting laser processing system for thin plate materials according to claim 2, characterized in that: It is characterized in that The diameter of the hole is set to 1-5 mm.

4. The water-conducting laser processing system for thin plate materials according to claim 1, characterized in that: The array porous support thin plate (20) is a thin plate supported by a material having a thermal expansion coefficient matching that of the thin plate (10) to be processed.

5. The water-conducting laser processing system for thin plate materials according to claim 4, characterized in that: The first clamp (6) clamps the thin plate to be processed (10) and the array porous support thin plate (20) in a multi-point positioning manner.

6. The water-conducting laser processing system for thin plate materials according to any one of claims 1 to 5, characterized in that: The water-conducting laser processing system is provided with a CCD camera (8) for collecting and photographing the cutting area according to a set sampling frequency to obtain an image of the processing area.

7. The water-conducting laser processing system for thin plate materials according to any one of claims 1 to 5, characterized in that: The sampling frequency of the CCD camera (8) is set to capture one frame of image every time the water-guided machining head (4) moves 0.1 mm.

8. The water-conducting laser processing system for thin plate materials according to claim 6, characterized in that: The control system of the water-conducting laser processing system is connected to a CCD camera (8), and obtains an angle deviation between the incision and the vertical direction based on image processing calculation according to the image of the processing area, which is used as the verticality deviation of the incision.

9. The water-conducting laser processing system for thin plate materials according to claim 8, characterized in that: The control system establishes a water-guided machining state space prediction model based on a water jet impact force model, a thin plate thermal deformation model, and a laser energy absorption and transfer model, with laser power, water jet pressure, and cutting speed as input vectors and a cut verticality deviation as an output vector; Based on the process parameters of each time step obtained by actual measurement and the verticality deviation of the cut, the coefficient matrix in the state space model is determined by a parameter identification method; The objective function is to minimize the sum of squares of the verticality deviation of the incision in the predicted time domain in the future, and the process parameter constraints are determined. The optimization solution is performed to obtain the input control sequence that minimizes the objective function while satisfying the process parameter constraints, and the compensation amount of the water-conducting laser processing process parameters is obtained, thereby ensuring the verticality of the processed incision.

10. The water-conducting laser processing system for thin plate materials according to claim 8, characterized in that: The step of calculating the angle deviation between the incision and the vertical direction based on the image of the processing area based on image processing includes: Preprocess and remove noise from the processed area image and convert it into a grayscale image; The edge of the grayscale image is extracted through edge detection, and the pixel points of the cut edge contour are obtained; Perform straight line fitting on the pixel points of the edge contour of the incision and calculate the slope and intercept of the fitting line to determine the shape and direction of the incision; The verticality deviation of the cut is calculated based on the angle between the fitting straight line and the ideal vertical direction.

Images