Multi-mode heat input cooperative regulation and control equipment of argon arc welding machine based on sheet metal part machining

Abstract

The invention relates to the technical field of intelligent welding, in particular to an argon arc welding machine multi-mode heat input cooperative regulation and control device based on sheet metal part machining, and the device comprises a sheet metal part welding quality evaluation module which obtains the welding quality score of each sheet metal part; the welding heat input interval limiting module is used for dividing the positions with the same thickness in all the sheet metal parts into one class, and determining a heat input suitable interval corresponding to each working mode in each class; the welding heat input optimization module is used for constructing a target function according to the heat input difference of adjacent welding positions of the current sheet metal part, and determining the optimal heat input of each welding position under each working mode when the current sheet metal part is welded; the welding arc voltage regulation and control module is used for determining the welding speed characteristic factor of each position in each type and the interference coefficient of each working mode in each type; and the regulation and control coefficient of each working mode is obtained, and the arc voltage at each moment under each working mode when the current sheet metal part is welded is regulated and controlled in real time. The welding quality of the sheet metal part is improved.

Description

Technical Field

[0001] This application relates to the field of intelligent welding technology, and specifically relates to an argon arc welding machine multi-mode heat input collaborative regulation device based on sheet metal processing. Background Art

[0002] An argon arc welding machine is a common welding device. It mainly uses argon gas as a shielding gas, generates an arc with a tungsten electrode, heats and melts metal workpieces through the high temperature of the arc, and finally completes the welding. The welding effect of the argon arc welding machine is stable and the weld seam is beautiful, especially suitable for high-quality and high-precision welding requirements. The processing of sheet metal parts often requires welding different metal plates together, and the argon arc welding machine is often used for sheet metal welding because of its precise control and welding effect.

[0003] In the welding of sheet metal parts by traditional argon arc welding machines, it is difficult for a single heat input mode to balance the deformation control of thin plate welding and the penetration requirement of thick plate welding. If the heat input is too high, it may cause coarsening of metal grains, embrittlement of the heat affected zone, and deformation of the workpiece; while if the heat input is too low, it may cause insufficient penetration, lack of fusion, or insufficient weld strength. At the same time, although existing equipment can adjust the heat input through independent parameters such as current and voltage, it lacks a dynamic coordination mechanism for parameters such as welding speed and arc voltage, resulting in unstable welding quality. Summary of the Invention

[0004] In order to solve the above technical problems, this application provides an argon arc welding machine multi-mode heat input collaborative regulation device based on sheet metal processing to solve existing problems.

[0005] The argon arc welding machine multi-mode heat input collaborative regulation device based on sheet metal processing of this application adopts the following technical solutions: An embodiment of this application provides an argon arc welding machine multi-mode heat input collaborative regulation device based on sheet metal processing. The device includes: Sheet metal part welding quality evaluation module: Obtain each sheet metal part welded by the argon arc welding machine in history, and obtain the welding quality score of each sheet metal part by evaluating the welding quality of each sheet metal part. Welding heat input interval limitation module: Divide the positions with the same thickness among all sheet metal parts into one category, and determine each reference position in each category based on the welding quality scores of the sheet metal parts corresponding to the positions in each category; Use the working modes during the welding process of the sheet metal parts corresponding to each reference position in each category and the heat input of the corresponding sheet metal parts to determine the appropriate heat input interval corresponding to each working mode in each category. Welding heat input optimization module: Before welding the current sheet metal part, take the appropriate heat input range as the value range of the heat input at each welding position of the current sheet metal part. Based on the heat input difference between adjacent welding positions of the current sheet metal part and in combination with the corresponding appropriate heat input range, construct an objective function, and use an optimization algorithm to determine the optimal heat input at each welding position under each working mode during the welding of the current sheet metal part; Welding arc voltage regulation module: Analyze the distribution of the welding speed at each position during welding in various types, and determine the welding speed characteristic factors at each position in various types; Based on the relationship between the welding quality score of the sheet metal part corresponding to each position under each working mode in various types and the change of the welding speed characteristic factor, determine the interference coefficients of each working mode in various types; Through the interference coefficients of all types under each working mode and in combination with the change rate of the above relationship, determine the regulation coefficients of each working mode. Based on the optimal heat input, determine the welding speed at each moment under each working mode during the welding of the current sheet metal part. In combination with the regulation coefficient and the arc voltage at each moment during the welding of the current sheet metal part, regulate the arc voltage at the next moment under each working mode during the welding of the current sheet metal part.

[0006] In one embodiment, the reference features for evaluating the welding quality of each sheet metal part include the weld forming coefficient, dimensional accuracy, and welding uniformity of the sheet metal part; The value range of the welding quality score is [0, 1].

[0007] In one embodiment, the reference position is the position corresponding to the sheet metal part where the welding quality score in various types is greater than the preset threshold.

[0008] In one embodiment, the determination of the appropriate heat input range corresponding to each working mode in various types includes: The working modes during the welding of the sheet metal part include the DC mode and the pulse mode. Obtain the minimum value and the maximum value of the heat input of the sheet metal parts corresponding to all reference positions belonging to the DC mode in various types, and use the numerical range composed of the minimum value and the maximum value as the appropriate heat input range corresponding to the DC mode in various types; Correspondingly, obtain the appropriate heat input range corresponding to the pulse mode in various types.

[0009] In one embodiment, the expression of the objective function is: ; where f is the objective function, is the difference between the heat input at the i-th position and the (i + 1)-th position during the welding of the current sheet metal part, is the difference between the heat input at the i-th position during the welding of the current sheet metal part and the middle value of the corresponding appropriate heat input range, and D is the number of welding positions of the current sheet metal part.

[0010] In one embodiment, the welding speed characteristic factor is the product of the reciprocal of the dispersion degree of the welding speed of the sheet metal parts corresponding to each position in each category during welding and the average level.

[0011] In one embodiment, determining the interference coefficient of each working mode in each category includes: For each working mode in each category, taking the welding speed characteristic factor of each position therein as the abscissa and the welding quality score of the sheet metal parts corresponding to each position therein as the ordinate, to obtain a fitting curve of the welding quality scores of the sheet metal parts corresponding to all positions in each working mode in each category with respect to the welding speed characteristic factor; Calculate the difference between the welding quality scores of each welding position on the fitting curve and its adjacent previous position, denoted as the first difference, and calculate the ratio of the sum value of all the first differences corresponding to the fitting curve to the sum value of the absolute values of all the first differences, as the interference coefficient of the working mode corresponding to the fitting curve in each category.

[0012] In one embodiment, determining the regulation coefficient of each working mode includes: Calculate the mean value of the slopes of all welding positions on the fitting curve, calculate the product of the mean value and the interference coefficient of the working mode corresponding to the fitting curve in each category, denoted as the first product, and take the mean value of the first products in all categories under each working mode as the regulation coefficient of each working mode.

[0013] In one embodiment, determining the welding speed at each moment in each working mode during the welding of the current sheet metal part includes: Using the calculation formula of the welding heat input, taking the optimal heat input of each welding position in each working mode during the welding of the current sheet metal part as a known quantity, and combining the arc voltage and current at the corresponding moment of each welding position during welding, to obtain the welding speed at each moment in each working mode during the welding of the current sheet metal part.

[0014] In one embodiment, regulating the arc voltage at the next moment of each moment in each working mode during the welding of the current sheet metal part includes: Calculate the product of the welding speed at each moment in each working mode during the welding of the current sheet metal part and the regulation coefficient of each working mode, denoted as the second product, and take the sum value of the arc voltage at each moment in each working mode during the welding of the current sheet metal part and the second product as the arc voltage at the next moment of each moment in each working mode during the welding of the current sheet metal part.

[0015] This application has at least the following beneficial effects: This application obtains each sheet metal part welded by the argon arc welder in the past, evaluates the welding quality of each sheet metal part, and obtains the welding quality score of each sheet metal part; the determination of the welding quality score quantifies the welding quality of the sheet metal part, improving the convenience of evaluating the welding quality of the sheet metal part; the positions with the same thickness among all sheet metal parts are divided into one category, and based on the welding quality scores of the sheet metal parts corresponding to the positions in each category, the reference positions in each category are determined; using the working mode during the welding process of the sheet metal parts corresponding to the reference positions in each category and the heat input of the corresponding sheet metal parts, the appropriate heat input range corresponding to each working mode in each category is determined, improving the accuracy of heat input parameter adaptation. Based on the welding mode and heat input data of the reference positions with the same thickness in the same category, a dynamic appropriate heat input range is established, avoiding the problems of insufficient penetration or burn-through defects caused by parameter deviation in the traditional process and solving the problem of heat input mismatch caused by local thickness mutation; before welding the current sheet metal part, the appropriate heat input range is used as the value range of the heat input at each welding position of the current sheet metal part. By the heat input difference between adjacent welding positions of the current sheet metal part and combining the corresponding appropriate heat input range, an objective function is constructed, and using an optimization algorithm, the optimal heat input at each welding position in each working mode during the welding of the current sheet metal part is determined, improving the accuracy and reliability of heat input determination during the welding of the sheet metal part and enhancing the scenario adaptability of heat input parameter determination; analyzing the distribution of the welding speed at each position during welding in each category, determining the welding speed characteristic factor at each position in each category, and the quantitative analysis of the welding speed characteristic factor realizes the quantitative evaluation of the stability and efficiency of the welding process, avoiding the insufficient adaptability of the traditional fixed speed strategy in variable working condition scenarios; based on the change relationship between the welding quality score of the sheet metal parts corresponding to each position in each category in each working mode and the welding speed characteristic factor, the interference coefficient of each working mode in each category is determined; through the interference coefficients of all categories in each working mode and combining the change rate of the change relationship, the regulation coefficient of each working mode is determined; based on the optimal heat input, the welding speed at each moment in each working mode during the welding of the current sheet metal part is determined, and combining the regulation coefficient and the arc voltage at each moment during the welding of the current sheet metal part, the arc voltage at the next moment in each working mode during the welding of the current sheet metal part is regulated. Through multi-parameter coupling closed-loop regulation, the thermodynamic state of the molten pool is maintained stable, and the hysteresis of single-parameter feedback control is avoided through coordinated control, improving the stability of sheet metal part welding and enhancing the welding quality. Description of the Drawings

[0016] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following-described drawings are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0017] Figure 1 Block diagram of the multi - mode heat input collaborative control device for an argon arc welder based on sheet metal processing provided by this application; Figure 2 Flow chart for adjusting the welding arc voltage. Specific embodiments

[0018] In order to further elaborate on the technical means and effects adopted by this application to achieve the intended invention purpose, the following combines the drawings and preferred embodiments to specifically describe the specific embodiments, structures, features and effects of the multi - mode heat input collaborative control device for an argon arc welder based on sheet metal processing proposed in this application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs.

[0020] The following specifically describes the specific solution of the multi - mode heat input collaborative control device for an argon arc welder based on sheet metal processing provided by this application with reference to the drawings.

[0021] The multi - mode heat input collaborative control device for an argon arc welder based on sheet metal processing provided by an embodiment of this application, specifically, provides the following block diagram of the multi - mode heat input collaborative control device for an argon arc welder based on sheet metal processing. Please refer to Figure 1 , The device includes: a sheet metal welding quality assessment module, a welding heat input range limiting module, a welding heat input optimization module, and a welding arc voltage control module.

[0022] S1. Sheet metal welding quality assessment module: Obtain each sheet metal welded by the argon arc welder in the past, and evaluate the welding quality of each sheet metal to obtain the welding quality score of each sheet metal.

[0023] Common argon arc welders usually include multiple working modes. Since for a continuous welding process, the main modes are the DC mode and the pulse mode, the working modes of the argon arc welder analyzed in this embodiment include the DC mode and the pulse mode. Among them, the DC mode is based on the DC positive - polarity connection method, with argon as the shielding gas, and the base metal and filler wire are melted by a stable arc to form a continuous weld. The current is always constant, and the arc stability is high, which is suitable for welding conventional thick plates; the pulse mode is based on DC argon arc welding, and the molten pool formation is controlled by periodically switching the base current and the peak current to form a dot - like superimposed weld.

[0024] During the process of welding sheet metal parts with different thicknesses, if the heat input is too high, it may cause coarsening of metal grains, embrittlement of the heat-affected zone, and deformation of the workpiece; while if the heat input is too low, it may result in insufficient penetration, lack of fusion, or insufficient weld strength. For sheet metal parts with different thicknesses under different working conditions, it is necessary to reasonably control the heat input during the welding process.

[0025] In this embodiment, taking any argon arc welding machine A as an example, all the sheet metal parts welded by the argon arc welding machine A in history are obtained, denoted as historical sheet metal parts. By comprehensively considering the weld formation coefficient, dimensional accuracy, whether there are defects, and the welding uniformity of each historical sheet metal part, these are used as reference factors, and the welding quality of each historical sheet metal part is scored manually to determine the welding quality score of each historical sheet metal part. Among them, the value range of the welding quality score is [0, 1], and the larger the welding quality score, the higher the welding quality of the historical sheet metal part.

[0026] S2, welding heat input interval limiting module: Divide the positions with the same thickness among all sheet metal parts into one category. Based on the welding quality scores of the sheet metal parts corresponding to each position in each category, determine each reference position in each category; use the working mode during the welding process of the sheet metal parts corresponding to each reference position in each category, and the heat input of the corresponding sheet metal parts, to determine the appropriate heat input interval corresponding to each working mode in each category.

[0027] For all the historical sheet metal parts of the argon arc welding machine, divide the positions with the same thickness among all the historical sheet metal parts into one category. For example, there are historical sheet metal parts B1, B2, B3, B4. Historical sheet metal part B1 includes thicknesses b11, b12, b13, historical sheet metal part B2 includes thicknesses b21, b22, b23, historical sheet metal part B3 includes thicknesses b31, b32, b33, and historical sheet metal part B4 includes thicknesses b41, b42, b43. Among them, b11 = b22 = b33, then divide the positions of the sheet metal parts corresponding to b11, b22, b33 into one category. If there is no same thickness, divide the position corresponding to a single thickness into one category.

[0028] It should be noted that the interval thickness of the sheet metal parts described in this embodiment is an interval range. For example, (0, 1mm] is one thickness, (1mm, 2mm] is one thickness, (2mm, 3mm] is one thickness, etc. One thickness corresponds to one position of the sheet metal part.

[0029] Obtain the welding quality scores of the historical sheet metal parts corresponding to all positions in each category. If the welding quality score is greater than the preset threshold, then take the corresponding position as the reference position in each category. In this embodiment, the preset threshold is set to 0.9, and the implementer can set it according to the actual situation, and this embodiment does not limit it here.

[0030] For all reference positions in each category, obtain the working modes during the welding process of the sheet metal parts corresponding to all reference positions, namely the DC mode and the pulse mode. Divide all reference positions with the same working mode in each category into a group. Since the working modes of welding analyzed in this embodiment include two types, the DC mode and the pulse mode, therefore, all reference positions in each category are divided into two groups, one group is the reference positions belonging to the DC mode, and the other group is the reference positions belonging to the pulse mode.

[0031] It should be noted that if there are reference positions in all reference positions in each category that do not belong to the DC mode nor the pulse mode, they will not be grouped.

[0032] For all reference positions belonging to the DC mode in each category, obtain the maximum value and the minimum value of the heat input of the sheet metal part corresponding to the reference position, and use the numerical interval formed by the minimum value and the maximum value as the appropriate heat input interval corresponding to the DC mode in each category.

[0033] For all reference positions belonging to the pulse mode in each category, obtain the maximum value and the minimum value of the heat input of the sheet metal part corresponding to the reference position, and use the numerical interval formed by the minimum value and the maximum value as the appropriate heat input interval corresponding to the pulse mode in each category.

[0034] It should be noted that the calculation method of the welding heat input is a well-known prior art, and the specific expression is ; in the formula, Q is the welding heat input, η is the heat efficiency, and for argon arc welding, the heat efficiency generally takes a value of 0.6 - 0.8, I is the welding current, U is the arc voltage, and v is the welding speed.

[0035] S3, welding heat input optimization module: Before welding the current sheet metal part, use the appropriate heat input interval as the value range of the heat input of each welding position of the current sheet metal part. Through the heat input difference between adjacent welding positions of the current sheet metal part, combined with the corresponding appropriate heat input interval, construct an objective function, and use an optimization algorithm to determine the optimal heat input of each welding position under each working mode during the welding of the current sheet metal part.

[0036] Since the magnitude of the welding heat input will directly affect the welding quality of the sheet metal part, therefore, in this embodiment, the optimal heat input during the welding of the current sheet metal part is determined with reference to the welding heat input of historical sheet metal parts, specifically: Before welding the current sheet metal part, optimize the heat input of each welding position during the welding of the current sheet metal part. Use the heat input of each welding position during the welding of the current sheet metal part as the optimization variable, and construct an objective function. The expression is: ; in the formula, f is the objective function, ΔQi is the difference in heat input between the i-th position and the (i + 1)-th position during the welding of the current sheet metal part, is the difference between the heat input at the i-th position during the welding of the current sheet metal part and the median value of the corresponding suitable heat input range, and D is the number of welding positions of the current sheet metal part.

[0037] In this embodiment, the particle swarm optimization algorithm is used to solve the objective function to obtain the optimal heat input at each welding position of the current sheet metal part during welding. Among them, the number of particles is set to 40, the value range of each dimension data of the particles is the suitable heat input range corresponding to the thickness at the corresponding position in the historical sheet metal parts, and the number of dimensions of the particles is the number of welding positions of the current sheet metal part. It should be understood that each welding position of the current sheet metal part corresponds to a thickness, and in the historical sheet metal parts, there will be a class corresponding to the equal thickness, and each of the two working modes in this class corresponds to a suitable heat input range. In this embodiment, the individual learning factor of the particle swarm optimization algorithm is set to 1.5, the social learning factor is set to 2.0, and the maximum number of iterations is set to 30 times. Implementers can set them according to the actual situation by themselves, and this embodiment does not limit them here. The particle swarm optimization algorithm solves the minimization of the objective function to obtain the optimal solution. The particle swarm optimization algorithm is a well-known prior art, and the specific process will not be elaborated. Implementers can choose other existing feasible optimization algorithms by themselves, and this embodiment does not limit them here.

[0038] It should be noted that since there are suitable heat input ranges for two working modes in the corresponding class of the historical sheet metal parts at each thickness position of the current sheet metal part, this embodiment can obtain the optimal heat input at each welding position under the two working modes during the welding of the current sheet metal part.

[0039] S4, welding arc voltage regulation module: (1) Analyze the distribution of welding speeds at each position during welding in each class to determine the welding speed characteristic factors at each position in each class; based on the relationship between the welding quality scores of the sheet metal parts corresponding to each position in each working mode in each class and the change of the welding speed characteristic factors, determine the interference coefficients of each working mode in each class.

[0040] Since the magnitude of the heat input is positively correlated with the voltage and current and negatively correlated with the welding speed; when the working mode during welding is in the DC mode, the current usually remains constant according to the equipment parameters of the argon arc welding machine. At this time, the heat input can be adjusted by adjusting the welding speed; specifically, according to the above steps, the optimal heat input at each welding position of the current sheet metal part is known, so the conversion of the welding speed can be directly carried out.

[0041] When the working mode during welding is in the pulse mode, the welding current is in a continuous changing process. At this time, when calculating the heat input, in this embodiment, the continuously changing welding current, that is, the dynamic current, is converted into a static current, and the static current is a fixed and unchanging current. The specific static conversion method is: Static current = Base current × Base duty cycle + Peak current × Peak duty cycle. At this time, based on the conversion method of the welding speed obtained in the DC mode, the welding speed in the pulse mode can be obtained.

[0042] During the process of welding sheet metal parts, when the welding speed increases, if the arc voltage remains constant, it may cause the arc length to be "stretched" or "compressed", resulting in the phenomenon of lack of fusion and a decline in welding quality. Therefore, it is necessary to coordinately control the welding speed and voltage.

[0043] It should be understood that the arc voltage and the arc length are approximately linearly related. When the welding speed increases, the arc voltage needs to increase slightly synchronously to maintain the stability of the arc length.

[0044] Therefore, this embodiment also analyzes based on various types divided by historical sheet metal parts, calculates the dispersion degree and average level of the welding speed when welding historical sheet metal parts at each position in each type, and takes the product of the reciprocal of the dispersion degree and the average level as the welding speed characteristic factor at each position in each type.

[0045] It should be noted that in this embodiment, the sampling time interval of the welding speed when welding historical sheet metal parts is 0.1 s, and the calculation method of the dispersion degree is variance. The implementer can set the sampling time interval and the calculation method of the dispersion degree according to the actual situation. For example, the dispersion degree can be calculated by methods such as standard deviation and coefficient of variation. This embodiment does not limit this here.

[0046] Furthermore, for each working mode in each type, taking the welding speed characteristic factor at each position as the abscissa and the welding quality score of the sheet metal parts corresponding to each position as the ordinate, the least squares method is used to perform curve fitting on all positions corresponding to each working mode in each type, and a fitting curve of the welding quality score of the sheet metal parts corresponding to all positions in each working mode in each type with respect to the welding speed characteristic factor is obtained. Among them, the least squares method is a well-known existing technology, and the implementer can select other existing feasible fitting algorithms by himself. This embodiment does not limit this here.

[0047] For each working mode in each type, calculate the difference between the welding quality score of each welding position on the fitting curve and its adjacent previous position, denoted as the first difference. Calculate the ratio of the sum value of all the first differences corresponding to the fitting curve to the sum value of the absolute values of all the first differences as the interference coefficient of the working mode corresponding to the fitting curve in each type, that is, the interference coefficient of each working mode in each type.

[0048] It should be understood that the value range of the interference coefficient is [-1, 1]. The closer this value is to -1, the more real the theoretical variation relationship between the welding quality and welding speed of the sheet metal parts is, and the higher the credibility of the obtained interference coefficient.

[0049] (2) Determine the regulation coefficient of each working mode through the interference coefficients of all classes under each working mode, combined with the change rate of the variation relationship. Based on the optimal heat input, determine the welding speed at each moment of each working mode during the welding of the current sheet metal part. Combine the regulation coefficient and the arc voltage at each moment during the welding of the current sheet metal part to regulate the arc voltage at the next moment of each moment of each working mode during the welding of the current sheet metal part.

[0050] For each working mode in each class, calculate the mean value of the slopes of all welding positions on the fitting curve, calculate the product of the mean value and the interference coefficient of the working mode corresponding to the fitting curve in each class, denoted as the first product. For all classes divided by all thickness positions on the historical sheet metal part, take the mean value of the first products in all classes of each working mode during the welding of the historical sheet metal part as the regulation coefficient of each working mode.

[0051] When welding the current sheet metal part, since the optimal heat input of each welding position of the current sheet metal part has been obtained in advance, therefore, using the calculation formula of the welding heat input, take the optimal heat input of each welding position of each working mode during the welding of the current sheet metal part as a known quantity, combined with the arc voltage and current at the corresponding moment of each welding position during welding, to obtain the welding speed at each moment of each working mode during the welding of the current sheet metal part. In this embodiment, it is set that when welding the current sheet metal part, the arc voltage at the initial moment of the argon arc welder is 12V, and the implementer can set it according to the actual situation, and this embodiment does not limit it here.

[0052] Furthermore, according to the relationship between the arc voltage and the welding speed, combined with the regulation coefficient of each working mode of the argon arc welder, the arc voltage of the argon arc welder is adjusted in real time. Specifically: Calculate the product of the welding speed at each moment of each working mode during the welding of the current sheet metal part and the regulation coefficient of each working mode, denoted as the second product. Take the sum value of the arc voltage at each moment of each working mode during the welding of the current sheet metal part and the second product as the arc voltage at the next moment of each moment of each working mode during the welding of the current sheet metal part, so as to complete the real-time adjustment of the arc voltage during the welding of the sheet metal part, thereby improving the welding quality of the sheet metal part. The flowchart of the welding arc voltage adjustment is as Figure 2 shown.

[0053] It should be noted that since two working modes of the argon arc welder are analyzed in this embodiment, and the real-time adjustment of the arc voltage can be completed in both working modes, the implementer can select the working mode of the argon arc welder according to the actual situation during actual operation, and this embodiment does not limit it here.

[0054] It should be noted that the above order of the embodiments of the present application is only for description and does not represent the superiority or inferiority of the embodiments. And the above specific embodiments of this specification have been described. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0055] Each embodiment in this specification is described in a progressive manner. For the same or similar parts between each embodiment, reference can be made to each other. The key point of each embodiment is to illustrate the differences from other embodiments.

[0056] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; modifying the technical solutions recorded in the foregoing embodiments, or equivalently replacing some of the technical features, does not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of each embodiment of the present application, and should all be included within the protection scope of the present application.

Claims

1. A multi-mode heat input coordinated control device for argon arc welding machine based on sheet metal processing, characterized in that: The equipment includes: Sheet metal welding quality assessment module: obtains the sheet metal parts welded by the argon arc welding machine in the past, evaluates the welding quality of each sheet metal part, and obtains the welding quality score of each sheet metal part; Welding heat input range limitation module: All positions of the same thickness in sheet metal parts are divided into one category, and the reference positions in each category are determined based on the welding quality scores of the sheet metal parts corresponding to each position in each category; the appropriate heat input range corresponding to each working mode in each category is determined by using the working mode of the sheet metal parts in the welding process corresponding to each reference position in each category and the heat input of the sheet metal parts; Welding heat input optimization module: before welding the current sheet metal part, the heat input suitable range is used as the value range of the heat input of each welding position of the current sheet metal part. The heat input difference of adjacent welding positions of the current sheet metal part is combined with the corresponding heat input suitable range to construct the objective function, and the optimization algorithm is used to determine the optimal heat input of each welding position under each working mode when welding the current sheet metal part; Welding arc voltage control module: Analyze the distribution of welding speed at each position in each category during welding, and determine the welding speed characteristic factor at each position in each category; Based on the relationship between the welding quality score of the sheet metal parts corresponding to each position in each working mode in each category and the change of the welding speed characteristic factor, determine the interference coefficient of each working mode in each category; The control coefficient of each working mode is determined by combining the interference coefficient of all classes under each working mode with the change rate of the change relationship. The welding speed at each moment in each working mode during the current sheet metal welding is determined based on the optimal heat input. The arc voltage at the next moment in each working mode during the current sheet metal welding is regulated by combining the control coefficient with the arc voltage at each moment during the current sheet metal welding.

2. The multi-mode heat input coordinated control device for argon arc welding machine based on sheet metal processing according to claim 1, characterized in that: The reference features for evaluating the welding quality of each sheet metal part include the weld formation coefficient, dimensional accuracy, and welding uniformity of the sheet metal part; the value range of the welding quality score is [0, 1].

3. The multi-mode heat input coordinated control device for argon arc welding machine based on sheet metal processing according to claim 1, characterized in that: The reference position is the position corresponding to the welding quality score of each type of sheet metal part being greater than a preset threshold.

4. The multi-mode heat input coordinated control device for argon arc welding machine based on sheet metal processing according to claim 1, characterized in that: The step of determining the appropriate heat input range corresponding to each working mode in each category includes: The working modes in the sheet metal welding process include direct current mode and pulse mode, and the minimum and maximum values ​​of the heat input of the sheet metal corresponding to all reference positions belonging to the direct current mode in each category are obtained, and the numerical range formed by the minimum and maximum values ​​is used as the suitable heat input range corresponding to the direct current mode in each category; Accordingly, the suitable range of heat input corresponding to each type of pulse mode is obtained.

5. The multi-mode heat input coordinated control device for argon arc welding machine based on sheet metal processing according to claim 1, characterized in that: The expression of the objective function is: ; Where f is the objective function, is the difference in heat input between the i-th position and the i+1-th position during the welding of the current sheet metal part. is the difference between the heat input at the i-th position during the welding of the current sheet metal and the middle value of the corresponding heat input suitable range, and D is the number of welding positions of the current sheet metal.

6. The multi-mode heat input coordinated control device for argon arc welding machine based on sheet metal processing according to claim 1, characterized in that: The welding speed characteristic factor is the product of the reciprocal of the discrete degree of the welding speed of the sheet metal parts corresponding to each position in each category during welding and the average level.

7. The multi-mode heat input coordinated control device for argon arc welding machine based on sheet metal processing according to claim 1, characterized in that: The determining of the interference coefficient of each working mode in each category includes: For each working mode in each category, the welding speed characteristic factor at each position is used as the horizontal coordinate, and the welding quality score of the sheet metal parts corresponding to each position is used as the vertical coordinate, so as to obtain the fitting curve of the welding quality score of the sheet metal parts corresponding to all positions under each working mode in each category with respect to the welding speed characteristic factor; The difference in welding quality score between each welding position on the fitting curve and its adjacent previous position is calculated and recorded as the first difference. The ratio of the sum of all the first differences corresponding to the fitting curve to the sum of the absolute values ​​of all the first differences is calculated as the interference coefficient of the working mode corresponding to the fitting curve in each category.

8. The multi-mode heat input coordinated control device for argon arc welding machine based on sheet metal processing according to claim 7, characterized in that: Determining the control coefficient of each working mode includes: The mean of the slopes of all welding positions on the fitting curve is calculated, and the product of the mean and the interference coefficient of the working mode corresponding to the fitting curve in each category is calculated, which is recorded as the first product. The mean of the first product in all categories under each working mode is used as the control coefficient of each working mode.

9. The multi-mode heat input coordinated control device for argon arc welding machine based on sheet metal processing according to claim 1, characterized in that: The determining of the welding speed at each moment in each working mode during the current sheet metal welding comprises: The calculation formula of welding heat input is used to take the optimal heat input of each welding position under each working mode during the current sheet metal welding as a known quantity. Combined with the arc voltage and current at each welding position at the corresponding moment during welding, the welding speed at each moment under each working mode during the current sheet metal welding is obtained.

10. The multi-mode heat input coordinated control device for argon arc welding machine based on sheet metal processing according to claim 1, characterized in that: The method of regulating the arc voltage at the next moment in each working mode during the current sheet metal welding comprises: Calculate the product of the welding speed at each moment in each working mode during the current sheet metal welding and the control coefficient of each working mode, record it as the second product, and take the sum of the arc voltage at each moment in each working mode during the current sheet metal welding and the second product as the arc voltage at the next moment in each working mode during the current sheet metal welding.

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