Adjustment and control method for angle compensation technology of flanging machine

Abstract

The invention relates to the technical field of flanging machines, in particular to a regulation and control method for an angle compensation technology of a flanging machine. Comprising the following steps: determining an angle deviation influence factor of the flanging machine; performing factor experiment design and working condition analysis; simulation and test data correction; establishing a polynomial response surface compensation model; according to the method, accurate forming can ensure that the angle deviation of a flanging product meets the precision requirement, so that the overall quality of the product is improved, material waste and the requirement for secondary machining are reduced, the production cost is reduced, and the economic benefit and the production efficiency are improved.

Description

Technical Field

[0001] The invention relates to the technical field of folding machines, and in particular to a control method for angle compensation technology of folding machines. Background Art

[0002] The folding machines currently on the market have the following problems: 1. Due to the promotion and popularization of lightweight structures, some machine tools lack rigidity and are easily deformed when folding with large loads, thus affecting the forming accuracy. 2. There are too many types and specifications of plates at present, and the forming accuracy is easily affected by material rebound and hardness, and the current theoretical model cannot be applied to all processed materials, resulting in low angle accuracy. Both of the above conditions have a great impact on the overall quality of the product, resulting in material waste and secondary processing, resulting in high production costs. Therefore, how to accurately control the angle compensation of the folding machine is a technical problem to be solved. Summary of the invention

[0003] The problem to be solved by the present invention is to provide a method for controlling the angle compensation technology of a folding machine, which has a fast control cycle and high compensation accuracy.

[0004] In view of the shortcomings of the prior art, the technical solution adopted by the present invention to solve the technical problems is: a method for controlling the angle compensation technology of a folding machine, comprising the following steps: S1. Determine the factors affecting the angle deviation of the folding machine: Based on the clamping force Y, folding force F, sheet width b, sheet thickness t, target angle D, gap multiple N, material yield strength , elastic modulus E, hardening index , establish the correlation model between angle deviation and folding force F; S2. Factor test design and operating condition analysis: Sample points are selected and the value range is set for the clamping force y, sheet width b, and sheet thickness t to generate simulation and test test groups, which are labeled , , , is the total number of experiments that need to be simulated and tested; S3. Simulation and test data correction: Finite element analysis of the folding machine model was performed using forming simulation software to obtain the folding force F and angle compensation P under each working condition, and the simulation results were reversely corrected based on the measured data. S4. Establish a polynomial response surface compensation model: Fitting the hemming force F and angle compensation P model based on orthogonal polynomial selection method; S5. Model verification and compensation implementation: Import the compensation model into the control system, verify the model accuracy by initializing the calibration conditions, and implement angle compensation control for different plate widths and thicknesses based on the calibration values.

[0005] Preferably, in step S1: the correlation model of the hemming force F further includes the material yield strength , elastic modulus E, hardening index , target angle D and gap multiple N, and are defined by the following proportional relationship: .

[0006] Preferably, in step S4: the polynomial response surface selects significant items by orthogonalization method and defines the error reduction ratio Filter key items, the expression is: , in, is the orthogonal coefficient, is the jth orthogonal coefficient, The target response value calculated for the kth sampling, , L is the total number of samplings; is the orthogonal term under the kth sampling, which can be obtained by Orthogonal transformation is obtained, retaining Items that are greater than the set threshold.

[0007] Preferably, in step S5: the input parameters for initializing the calibration working condition include sheet thickness t, sheet width b, target angle D, the output is folding force F and angle compensation P, and dynamic adjustment of parameters is achieved through the control system interface.

[0008] Preferably, in step S3: the boundary conditions for the forming simulation software to perform finite element analysis on the folding machine model include fixing the clamping die, applying a bending load to the contact surface of the sheet metal, and meshing using an adaptive encryption strategy to improve the calculation accuracy of the stress concentration area.

[0009] Preferably, the model of the folding force F and the angle compensation amount P is as follows: ; ; Where D is the target angle, N is the gap multiple, is the yield strength of the material, E is the elastic modulus, is the hardening index, A, B, C are fitting coefficients; t is the sheet thickness, b is the sheet width, F is the folding force, Y is the clamping force, are fitting coefficients, 16 in total.

[0010] The beneficial effects of the present invention are as follows: The present invention develops a control method for the angle compensation model of the folding machine based on the polynomial response surface function by means of multi-factor experimental design and the combination of simulation and testing. The present invention significantly improves the precision of the folding machine components, reduces the cost of test pieces, and can efficiently and reliably meet the processing requirements. The method of the present invention has important practical research significance for the control of the forming precision of the folding machine. Accurate forming can ensure that the angle deviation of the folded product meets the precision requirements, thereby improving the overall quality of the product, reducing material waste and the need for secondary processing, thereby reducing production costs, and improving economic benefits and production efficiency. In addition, high-precision folding forming can support more complex and innovative product designs, broaden the design space of products, and enhance market competitiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 A flowchart of a control method for the angle compensation technology of a folding machine provided by the present invention; Figure 2 A flowchart of the actual application operation of the folding machine angle compensation model provided by the present invention; Figure 3 The interaction relationship between the pressing die and the folding die involved in the present invention; Figure 4 It is a schematic diagram of the sheet material folding forming according to the present invention; Explanation of the accompanying drawings: 1. Pressing die; 2. Sheet material; 3. Folding die. DETAILED DESCRIPTION

[0012] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present invention are provided for the purpose of illustration and description, and are not intended to be exhaustive or to limit the present invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention, and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

[0013] In order to solve the problem raised in the background technology, the present invention provides a method for controlling the angle compensation technology of a folding machine, such as Figure 1 The figure shows a flow chart of the control method of the folding machine angle compensation technology, which specifically includes the following steps: S1. Determination of factors affecting the angle deviation of the folding machine: According to the working principle of the folding machine, the angle forming process mainly depends on the interaction between the pressing die 1 and the folding die 3, such as Figure 3The figure shows the interaction between the clamping die 1 and the folding die 3. The clamping die 1 is located above the sheet 2 and mainly plays the role of fixing the sheet 2, thereby preventing the sheet 2 from shifting or deforming during the folding process. The folding die 3 is located below the sheet 2 and is mainly responsible for bending the sheet 2 to form the desired folding shape. The clamping die 1 and the folding die 3 cooperate with each other to achieve the target angle. Therefore, the factors affecting the angle deviation mainly include: ; Among them, Y is the pressing force, F is the folding force, b is the sheet width, and t is the sheet thickness. The factors affecting the folding force mainly include: ; Where D is the target angle, N is the gap multiple, is the yield strength of the material, E is the elastic modulus, is the hardening index.

[0014] S2. Test condition analysis based on multi-factor experimental design: According to the three adjustable variable parameters (clamping force Y, sheet width b and sheet thickness t) determined in the above step S1, the number of sample points and value ranges of different variables are determined, and a simulation and test table is established accordingly, and a variety of different working condition test groups are obtained, which are labeled as , , is the total number of experiments that need to be simulated and tested.

[0015] S3. Compensation value solution based on simulation and test data: According to the various working condition test groups with different forming angles determined in the above step S2, the simplified models of the clamping device and the folding device of the folding machine are imported into the SimufactForming software for forming simulation analysis. The meshing of the simplified model is performed by automatic division. The forming trajectory of the folding die 3 and the load required for the clamping force are applied in the pre-processing. According to each group of working conditions in the test table, the corresponding folding force F and angle compensation P are obtained based on the simulation software solution, where , is the total number of tests. On this basis, some working conditions were selected for test verification based on the test method of folding angle forming, and the finite element calculation results were reversely corrected by the test and simulation error values ​​to ensure the accuracy and reliability of simulation data modeling.

[0016] S4. Establishment of angle deviation compensation model based on polynomial response surface: According to the parameters of different working condition combinations determined in step S2, combined with the simulation in step S3, the folding force and angle compensation corresponding to each group of working conditions are solved, and the polynomial response surface function is fitted for the folding force F and angle compensation P corresponding to different working conditions in the numerical analysis software.

[0017] The polynomial response surface represents the response function as a complete polynomial combination of n parameters, that is, ; In the formula, For variables The complete polynomial of ; is the coefficient to be determined; is the total number of items, The expression is: .

[0018] The multinomial selection method was used to The significance of each term in is evaluated, and effective polynomial terms are selected based on the concept of optimal error reduction ratio, redundant terms are removed, and the optimal polynomial response surface is obtained.

[0019] To determine the polynomial model and its coefficients, Transformed into an orthogonal set form, that is: ; In the formula, The target response value calculated for the kth sampling, , L is the total number of samplings; is the orthogonal term under the k-th sampling, which can be obtained by Orthogonal transformation is obtained; is the orthogonal term coefficient.

[0020] according to The orthogonal relationship among the terms in the equation can be deduced as follows: .

[0021] use Orthogonalization, It is expressed as: ; In the formula, ; is the kth sampling polynomial; orthogonal polynomial coefficients It can be expressed as: ; Define the error function for: ; right middle Taking the derivative and setting it equal to 0, it can be expressed as: ; Will Substitution In, based on Each term is orthogonal, and is a constant, the error function It can be expressed as: ; The maximum value of , orthogonal terms right The reduced contribution is Therefore, the error reduction ratio is defined to quantify the effect of each orthogonal term on the error function The reduced contribution rate is: ; In the formula, .

[0022] After each orthogonal transformation, calculate each pair Reduced contribution rate , select the item with the largest error reduction ratio, and repeat the above method until the largest error is found in the remaining items. If it is less than the set threshold, the remaining items are discarded. Then solve , obtained by inverse orthogonal transformation The coefficient of the reserved term.

[0023] According to the influencing factors of the angle deviation in step S1 and the compensation value obtained by test and simulation in step S3, the folding force calculation model is established based on the above polynomial fitting method: ; Where D is the target angle, N is the gap multiple, is the yield strength of the material, E is the elastic modulus, is the hardening index, and A, B, and C are the fitting coefficients for calculating the folding force.

[0024] The above-mentioned folding force F is converted into units (from N to ton), and the angle deviation compensation model is also established based on polynomial fitting: ; Among them, t is the sheet thickness, b is the sheet width, F is the folding force, and Y is the clamping force. (i is the subscript number) is the angle deviation fitting coefficient, there are 16 in total.

[0025] S5. Verification and correction based on compensation model: The angle compensation model is encapsulated and imported into the control system. According to the polynomial response surface function fitting in the above S4 step, the folding force F and angle compensation P corresponding to a single working condition (i.e., the initialization calibration condition) are obtained for a single machine model, and the required initialization calibration value is solved. The angle compensation switch is turned on in the operation interface, and the calibration value is input in the system interface. Based on the calibration value, the calculation of different plate widths under the same thickness can be realized.

[0026] The parameters involved in the above text are as follows: Y: clamping force; F: folding force; b: sheet width; t: sheet thickness; D: target angle; N: gap multiple; : material yield strength; E: elastic modulus; : Hardening index; P: Angle compensation; : coefficient to be determined; : orthogonal term under the k-th sampling; : orthogonal term coefficient; : orthogonal polynomial coefficients; : Contribution rate of the jth orthogonal polynomial to the error function; A, B, C: Fitting coefficients for folding force calculation; : Angle deviation fitting coefficient.

[0027] Taking a folding machine as an example, the actual application operation process of the compensation model under the working condition of plate thickness of 1.5mm is carried out. Before the angle compensation model is applied, it is necessary to ensure that the machine tool has been debugged and inspected and can be delivered for normal use. Before initializing the calibration working condition test, it is necessary to turn off all angle compensation settings in the system to ensure the accuracy of the initialization calibration results. Taking the working condition of sheet thickness t of 1.5mm and sheet width b of 1000mm as an example, firstly, the required clamping force Y is obtained as 88% through load debugging, and then the angle deviation is measured and calculated using an angle ruler. The angle deviation is 3.55°, and then the angle deviation is subtracted from the modeling data value when the sheet thickness t is 1.5mm, and the initial calibration value is -1.87°. Finally, turn on the angle compensation switch, enter -1.87 in the system interface, and select the appropriate clamping force according to the different plate widths. After all is completed, start bending. Using this compensation technology, the angle deviation before and after is reduced from ±5° to ±1°. When the compensation model fails (the compensated forming angle fails to meet the accuracy requirements), the angle compensation switch can be turned off, and higher-precision folding forming can be achieved by manually changing the angle deviation.

[0028] The present invention provides a method for angle compensation and control of a folding machine based on multi-factor experimental design and a polynomial response surface model. By systematically analyzing the factors affecting the angle deviation and combining simulation with measured data correction, a high-precision compensation model is constructed. This method significantly improves the angle accuracy of folding forming, reducing the deviation from ±5° of the traditional method to ±1°, effectively reducing material waste and secondary processing requirements, and reducing production costs. Through dynamic parameter adjustment and model verification, the present invention can adapt to different sheet specifications and processing scenarios, support complex product design, and enhance market competitiveness. In addition, the modular compensation model design simplifies system maintenance and has broad industrial application prospects.

Claims

1. A method for controlling the angle compensation technology of a folding machine, characterized in that: The following steps are involved: S1. Determine the factors affecting the angle deviation of the folding machine: Based on the clamping force Y, folding force F, sheet width b, sheet thickness t, target angle D, gap multiple N, material yield strength , elastic modulus E, hardening index , establish the correlation model between angle deviation and folding force F; S2. Factor test design and operating condition analysis: Sample points are selected and the value range is set for the clamping force Y, sheet width b, and sheet thickness t to generate simulation and test groups, labeled as , , is the total number of experiments that need to be simulated and tested; S3. Simulation and test data correction: Finite element analysis of the folding machine model was performed using forming simulation software to obtain the folding force F and angle compensation P under each working condition, and the simulation results were reversely corrected based on the measured data. S4. Establish a polynomial response surface compensation model: Fitting the hemming force F and angle compensation P model based on orthogonal polynomial selection method; S5. Model verification and compensation implementation: Import the compensation model into the control system, verify the model accuracy by initializing the calibration conditions, and implement angle compensation control for different plate widths and thicknesses based on the calibration values.

2. The control method of the folding machine angle compensation technology according to claim 1 is characterized in that: In step S1: the correlation model of the hemming force F further includes the material yield strength , elastic modulus E, hardening index , target angle D and gap multiple N, and are defined by the following proportional relationship: 。 3. The control method of the folding machine angle compensation technology according to claim 2 is characterized in that: In step S4: the polynomial response surface selects significant items through orthogonalization method and defines the error reduction ratio Filter key items, the expression is: ， in, is the orthogonal coefficient, is the jth orthogonal coefficient, The target response value calculated for the kth sampling is, , L is the total number of samplings; is the orthogonal term under the kth sampling, which can be obtained by Orthogonal transformation is obtained, retaining Items that are greater than a set threshold.

4. The method for controlling the angle compensation technology of the folding machine according to claim 1, characterized in that: In the step S5: the input parameters of the initialization calibration working condition include the sheet thickness t, the sheet width b, and the target angle D, and the output is the folding force F and the angle compensation amount P, and the parameters are dynamically adjusted through the control system interface.

5. The method for controlling the angle compensation technology of the folding machine according to claim 1, characterized in that: In step S3: the boundary conditions for the finite element analysis of the folding machine model by the forming simulation software include fixing the clamping die (1), applying a bending load to the contact surface of the sheet material (2), and meshing using an adaptive encryption strategy to improve the calculation accuracy of the stress concentration area.

6. The method for controlling the angle compensation technology of the folding machine according to claim 3, characterized in that: The model of folding force F and angle compensation P is as follows: ； ； Where D is the target angle, N is the gap multiple, is the yield strength of the material, E is the elastic modulus, is the hardening index, A, B, C are fitting coefficients; t is the sheet thickness, b is the sheet width, F is the folding force, Y is the clamping force, are fitting coefficients, 16 in total.

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