A metal wire automatic processing machine tool for clamping workpiece and control method thereof

Abstract

The present application relates to the field of machine tool control technology, and specifically to an automated wire processing machine tool for workpiece clamping and a control method thereof. The method comprises: collecting a welding current sequence; obtaining the frequency domain of the welding current sequence, and then obtaining a welding cycle, dividing the welding current sequence into current subsequences based on the welding cycle, and obtaining the smooth continuity of the elements according to the difference in the local markings of the current subsequence elements; obtaining the current smooth transition amount based on the smooth continuity of the differential sequence elements and the coefficient of variation of its welding current change sequence; labeling the welding cycle, combining the current smooth transition sequence element value and the mean of the element at the corresponding position to obtain the time flow difference; and obtaining the automatic differential parameters of the current time period based on all the time flow differences of the current time period and the time flow differences of the first two adjacent time periods; and controlling the current of the processing machine tool in real time to weld according to the automatic differential parameters. The present application effectively improves the quality of wire welding.

Description

Technical Field

[0001] The present application relates to the technical field of machine tool control, and in particular to a workpiece clamping metal wire automatic processing machine tool and a control method thereof. Background Art

[0002] In the process of express sorting, storage cages are needed to temporarily store express. In order to ensure the high bearing capacity and durability of storage cages, metal wires are generally used for welding in the manufacture of storage cages. In the process of welding metal wires through processing machine tools, since the storage cage is a mesh structure, one metal wire is usually connected to multiple metal wires, resulting in multiple welding points. In the process of welding on the processing machine tool, it is necessary to move the electrode of the processing machine tool. When the electrode moves, the length of the arc of the processing machine tool will change, causing the voltage applied to the arc to change. As a result, the current of the processing machine tool changes, and the size of the welding current directly affects the quality of the welding point. Too small a current may cause the welding point to fail to melt completely and the strength is insufficient; while too large a current may cause spatter during welding or too deep indentations on the surface of the workpiece, resulting in reduced shear strength.

[0003] The machining center is a commonly used machining center with multi-dimensional automatic moving tracks. By inputting programming, the machining of the workpiece can be automatically completed. During machining, the workpiece is fixed on the machining table, and the machining of the workpiece is completed by the automatic shifting of the workpiece and the automatic feeding of the tool. Since all movements are mechanically controlled automatically, the machining accuracy is relatively high. The traditional technology generally adjusts and controls the current of the machining center through PID control. However, when using metal wire to weld the storage cage, there are many welding points on the storage cage with irregular shapes, which makes the stability and intensity of the current of the machining center different during the welding process. When using PID with fixed differential parameters to control the current of the machining center, unstable control is prone to occur, resulting in poor welding quality of the welding points between the metal wires. Summary of the invention

[0004] In order to solve the technical problem of poor welding quality caused by unstable current, the present application provides a workpiece clamping wire automatic processing machine tool and a control method thereof, and the technical solution adopted is as follows:

[0005] In a first aspect, the present application proposes a control method for a workpiece clamping wire automatic processing machine tool, the method comprising the following steps:

[0006] The metal wire is fixed and clamped on the welding table, and arranged horizontally and vertically for welding; a current sensor is installed on the processing machine tool to collect the current within a period of time to form a welding current sequence;

[0007] The welding current sequence is transformed into the frequency domain to obtain the welding cycle of the welding current sequence, and the welding current sequence is divided into multiple current subsequences based on the welding cycle; the difference sequence of the calculated current subsequence is recorded as the current difference sequence, and the absolute value of the elements in the current difference sequence is taken to obtain the welding current change sequence; the elements in the current difference sequence are marked, and a window is constructed for each element in each current difference sequence, and the smooth continuity of each element is obtained according to whether the marks of adjacent elements in the window are the same; for each element of the welding current change sequence, a window of the same size as the current difference sequence is constructed, and the current smooth transition amount of each element is obtained according to the smooth continuity of each element of the current difference sequence and the coefficient of variation of the local window sequence of the elements at the same position of the welding current change sequence;

[0008] The current smooth transition amounts of all elements of each current subsequence constitute a current smooth transition sequence, the welding cycles are marked with serial numbers in chronological order, and the time flow difference at each moment is obtained according to the difference between the value of each element of the current smooth transition sequence of all welding cycles and the mean value of all elements at the corresponding position and the serial number of the welding cycle; the time response difference is obtained based on the mean value of the time flow difference, and the automatic differential parameter of the current time period is obtained according to the difference between the time response differences of the two time periods before the current time period and the automatic differential parameter of the previous time period;

[0009] The current is controlled in real time according to the automatic differential parameters to complete automatic welding.

[0010] In the above scheme, the present application monitors the automated welding process of the metal wire and controls the welding parameters based on the current sensing technology and data analysis method, characterizes the dynamic characteristics of the welding current by real-time acquisition of the current data in the welding process; characterizes the stability and quality of the welding process by analyzing the fluctuation and change of the current data; combines the analysis of the influencing factors of the welding current to evaluate the relationship between the welding quality and the structural strength, thereby determining the current stability in the welding process, and intelligently controls the current fluctuation in the metal wire welding process by adjusting the automated differential parameters, thereby improving the accuracy and efficiency of the metal wire welding under various operating conditions. Therefore, the present invention avoids the problem of the inability to accurately control the welding current in the metal wire welding monitoring method in the prior art, and can effectively improve the accuracy and efficiency of the metal wire welding monitoring.

[0011] In one embodiment, the method of performing frequency domain conversion on the welding current sequence to obtain the welding cycle of the welding current sequence and dividing the welding current sequence into multiple current subsequences based on the welding cycle is:

[0012] Input the welding current sequence, obtain the frequency domain of the welding current sequence based on Fourier transform, obtain the amplitude corresponding to each frequency in the frequency domain, record the frequency corresponding to the maximum amplitude as the first frequency, take the inverse of the first frequency as the welding cycle of the welding current sequence, and divide the welding current sequence according to the welding cycle to obtain several current sub-sequences.

[0013] In one embodiment, the method of marking the elements in the current differential sequence, building a window for each element in each current differential sequence, and obtaining the smooth continuity of each element according to whether the marks of adjacent elements in the window are the same is:

[0014] Add a mark to the elements in the current differential sequence. When the value of the element is positive, it is marked as 1; when the value of the element is 0, it is marked as 0; when the value of the element is negative, it is marked as -1;

[0015] A local window is obtained with each element as the center in the current difference sequence, and all elements in the local window are recorded as a local window sequence;

[0016] Any element in the current differential sequence is recorded as the target element. If each element in the local window corresponding to the target element has the same mark value as the next element, the continuous value of the element is recorded as 1, otherwise the element value is recorded as 0, and the continuous value of the last element is recorded as 0. The continuous values ​​of all elements in the local window are accumulated as the smooth continuity of the target element.

[0017] In one embodiment, the method for obtaining the current smooth transition amount of each element according to the smooth continuity of each element of the current difference sequence and the coefficient of variation of the local window sequence of the elements at the same position of the welding current change sequence is:

[0018] The amount of current smooth transition is positively correlated with smooth continuity, and negatively correlated with the coefficient of variation of the local window sequence of the welding current change sequence elements.

[0019] In one embodiment, the method for obtaining the time flow difference at each moment according to the difference between the value of each element of the current smooth transition sequence of all welding cycles and the mean value of all elements at the corresponding position and the sequence number of the welding cycle is:

[0020] The serial number of the welding cycle is recorded as the time flow coefficient;

[0021] , It represents the time flow difference at the pth moment of the welding cycle; Indicates the number of welding cycles; represents the time flow coefficient; represents the pth element in the current smooth transition sequence of the qth welding cycle; Represents the mean value of the pth element in the current smooth transition sequence of all welding cycles.

[0022] In one embodiment, the method for obtaining the automatic differential parameter of the current time period according to the difference between the time response differences of the two time periods before the current time period and the automatic differential parameter of the previous time period is:

[0023] Record the current time period as the time period to be adjusted, record the previous time period of the time period to be measured as the first historical time period, and record the previous time period of the first historical time period as the second historical time period; calculate the time response difference of the last welding cycle in the first historical time period and the second historical time period;

[0024] The automatic differential parameter of the time period to be adjusted is obtained based on the difference in time response difference between the last welding cycle of the first historical time period and the second historical time period and the automatic differential parameter of the first historical time period.

[0025] In one embodiment, the expression of the automatic differentiation parameter is:

[0026] , The automatic differential parameter representing the time period to be adjusted; Indicates the automated differential parameter for the first historical period; represents the time response difference of the first period of history; represents the difference in time response for the second period of history; Represents the sigmoid function.

[0027] In one embodiment, the method for controlling the current in real time according to the automatic differential parameter is:

[0028] For the current time period, the automatic differential parameters of the current time period are calculated, the calculated automatic differential parameters are used to replace the existing differential parameters, the current of the current time period is input, and the current of the current time period is controlled based on the PID control algorithm.

[0029] In one embodiment, the expression of the current smooth transition amount is:

[0030] , It represents the current smooth transition amount of the kth element in the welding current change sequence; It represents the smooth continuity of the kth element in the periodic current difference sequence; represents the coefficient of variation of the kth element window sequence in the welding current variation sequence, Represents the adjustment factor.

[0031] In the second aspect, an embodiment of the present application also provides an automated wire processing machine tool for workpiece clamping, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein when the processor executes the computer program, the steps of the control method of the automated wire processing machine tool for workpiece clamping described in any one of the above items are implemented.

[0032] The beneficial effects of this application are:

[0033] The present application monitors the automated welding process of the metal wire and controls the welding parameters based on the current sensing technology and data analysis method, characterizes the dynamic characteristics of the welding current by real-time acquisition of the current data during the welding process; characterizes the stability and quality of the welding process by analyzing the fluctuations and changes of the current data; combines the analysis of the influencing factors of the welding current to evaluate the relationship between the welding quality and the structural strength, thereby determining the current stability during the welding process, and intelligently controls the current fluctuations during the metal wire welding process by adjusting the automated differential parameters, thereby improving the accuracy and efficiency of the metal wire welding under various operating conditions. Therefore, the present invention avoids the problem of the inability to accurately control the welding current in the metal wire welding monitoring method in the prior art, and can effectively improve the accuracy and efficiency of the metal wire welding monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 A flow chart of a control method for a workpiece clamping metal wire automatic processing machine tool provided by one embodiment of the present application;

[0036] Figure 2 Schematic diagram of welding current change. DETAILED DESCRIPTION

[0037] In order to further explain the technical means and effects adopted by the present application to achieve the predetermined invention purpose, the following is a detailed description of the specific implementation method, structure, features and effects of a workpiece clamping wire automatic processing machine tool and its control method proposed in the present application in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0038] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0039] An automatic wire processing machine tool for clamping a workpiece and a control method thereof Embodiment:

[0040] The specific scheme of the control method of the metal wire automatic processing machine tool for clamping a workpiece provided by the present application is described in detail below with reference to the accompanying drawings.

[0041] See also Figure 1 , which shows a flow chart of a control method for a workpiece clamping wire automatic processing machine tool provided by an embodiment of the present application, the method comprising the following steps:

[0042] Step S001, fix and clamp the metal wire on the welding table, arrange it horizontally and vertically for welding; install a current sensor on the processing machine tool, collect the current within a time period to form a welding current sequence.

[0043] When welding the metal wires, each metal wire is clamped by a clamping device, thereby fixing the metal wires on the welding table, and the metal wires are arranged horizontally and vertically, with the vertical wires at the bottom and the horizontal wires at the top; in this embodiment, the spacing between the vertical wires is 5 cm, and the spacing between the horizontal wires is 10 cm; in actual welding, the spacing between the metal wires is determined by the material of the metal wires and the size of the welding object.

[0044] A current sensor is installed on the processing machine to collect the current value of the processing machine during the welding process, collect the current within a period of time, arrange the collected current data in the order of the collection time, and use the mean interpolation method to complete the missing data of the arranged current, and the completed data is called a welding current sequence. In this embodiment, the collection frequency is 10kHz, and the total collection time is 0.1s, that is, every 0.1s is used as a time period, the current data of the processing machine is collected, and a welding current sequence is obtained every 0.1s. The calculation method of the mean interpolation method is a well-known technology and will not be repeated in this application.

[0045] At this point, the welding current sequence is acquired.

[0046] Step S002, obtain the frequency domain of the welding current sequence, and then obtain the welding cycle, divide the welding current sequence into current subsequences based on the welding cycle, and obtain the smooth continuity of the elements according to the differences in local markings of the current subsequence elements; obtain the current smooth transition amount of the elements based on the smooth continuity of the differential sequence elements of the current subsequence and the coefficient of variation of the local window of its welding current change sequence.

[0047] The welding point of the metal wire is the junction of the horizontal and vertical metal wires. When the metal wire moves for welding, the welding process includes three parts: arcing stage, pulse stage, and short circuit stage. In the arcing stage, the current of the processing machine tool will increase first, then remain constant, and then rise to the peak value; in the pulse stage, the current remains constant, and then quickly drops to the trough; in the short circuit stage, it remains constant, then rises and remains for a very short time, such as Figure 2 shown.

[0048] In a normal welding process, if you want to achieve better welding results, you need to maintain the stability of the welding current during the welding process. This is because during the welding process, unstable current can easily lead to irregular molten droplet transition during the arcing stage, causing molten droplet splashing during the welding process. In addition, unstable current leads to different degrees of melting of the molten droplets, thus affecting the quality of metal wire welding.

[0049] For each welding current sequence, it contains multiple welding cycles, and one welding cycle includes arcing stage, pulse stage, and short circuit stage. The welding current sequence is used as the input of Fourier transform, and the output is the frequency domain of the welding current sequence. The frequency in the frequency domain represents the number of periodic changes within the current gear time, and the frequency with the maximum amplitude represents the main periodic change of the welding current. Therefore, the frequency with the largest amplitude in the frequency domain data is recorded as the first frequency, and the reciprocal of the first frequency is used as the welding cycle length of the welding current sequence. The welding cycle length is the time length of one welding cycle.

[0050] The welding current sequence is divided according to the welding cycle length to obtain multiple subsequences with the same length as the welding cycle length, and each subsequence is recorded as a current subsequence to characterize the change state of the current of the processing machine tool during the welding process under different welding cycles. The method of obtaining the cycle length by Fourier transform is a well-known method, and the specific process is not repeated in this embodiment.

[0051] In an ideal welding situation, the changing state of the current should be smooth. At different stages of welding, the local state of the current is the same or similar. Therefore, the current subsequence is used as the input of the first-order difference method, and the differential sequence of the current subsequence is output, which is recorded as the current differential sequence. Since the current changes in the welding process, there are three situations: rising, stable, and falling. Therefore, the absolute value of the elements in the current differential sequence is taken, and the obtained sequence is used as the welding current change sequence, which is used to characterize the stability of the current during the welding process.

[0052] For the current differential sequence of the welding cycle, the elements in the sequence have continuity of local current signs under ideal conditions, that is, all local currents are positive, all local currents are negative, and all local currents are 0. Add a mark to the elements in the current differential sequence. When the value of the element is positive, it is marked as 1; when the value of the element is 0, it is marked as 0; when the value of the element is negative, it is marked as -1. For each current differential sequence, a local window is obtained with each element as the center. In this embodiment, the length of the local window is 15. All elements in the local window are recorded as a local window sequence. If the number of elements in the local window is insufficient, the mean filling method is used to fill it.

[0053] For the current difference sequence, the smooth continuity of each element is obtained according to the label difference of the adjacent elements in the local window corresponding to each element.

[0054] Any element in the current differential sequence is recorded as the target element. If the mark value of each element in the local window corresponding to the target element is the same as that of the next element, the continuous value of the element is recorded as 1, otherwise the element value is recorded as 0, and the continuous value of the last element is recorded as 0. The continuous values ​​of all elements in the local window are obtained, and the continuous values ​​of all elements are accumulated as the smooth continuity of the target element.

[0055] In the actual welding process, due to the complex welding environment, the welding current becomes unstable to a certain extent, resulting in different marked values ​​of the welding current and a continuous value of 0 for the element, which results in a smaller smooth continuity of the current of the element in the current differential sequence. This means that when welding the metal wire at this moment, the temperature of the molten droplet will be unstable, which will cause spattering during welding and lead to problems with the welding quality. Therefore, it is necessary to increase the control of the current of the processing machine tool during welding so that the current of the processing machine tool can run smoothly and ensure the welding quality of the metal wire.

[0056] For the welding current change sequence, a local window of the same size as each element of the current differential sequence is obtained for each element therein, and the corresponding local window sequence is obtained. Under ideal conditions, the welding current changes smoothly during welding without unstable changes. The smooth continuous length of the elements in the welding current change sequence is equal to the number of elements in the window sequence, and the elements in the window sequence differ slightly. The ideal welding state is conducive to the continuity and uniformity of the welding process, and reduces the problems of false solder joints and multiple solder joints in the metal wire welding.

[0057] The current smooth transition amount of each element is obtained based on the smooth continuity of each element in the current difference sequence and the coefficient of variation of the local window sequence of the elements at the same position in the welding current variation sequence.

[0058] The amount of current smooth transition is positively correlated with smooth continuity, and negatively correlated with the coefficient of variation of the local window sequence of the welding current change sequence elements.

[0059] It should be noted that positive correlation means that when one variable increases, the other variable also increases, and the two variables change in the same direction. When one variable changes from large to small or from small to large, the other variable also changes from large to small or from small to large. The specific relationship is determined by actual application and this application does not impose any special restrictions.

[0060] It should be noted that negative correlation means that when one variable increases, the other variable decreases accordingly, and the two variables change in opposite directions. When one variable changes from large to small or from small to large, the other variable also changes from small to large or from large to small. The specific relationship is determined by actual application and this application does not impose any special restrictions.

[0061] The expression of the current smooth transition amount is:

[0062] , It represents the current smooth transition amount of the kth element in the welding current change sequence; It represents the smooth continuity of the kth element in the periodic current difference sequence; represents the coefficient of variation of the kth element window sequence in the welding current variation sequence, Represents the adjustment factor, with a value of 0.1, which is used to prevent the denominator from being 0.

[0063] In the process of wire welding, when the welding is carried out smoothly, whether it is the arc burning stage, pulse stage or short circuit stage of welding, the current value has a long continuity in each change, so the value of the smooth continuity length of the elements in the current difference sequence is large; and the change state at different moments in each stage is similar or the same, so the value of the coefficient of variation of the window sequence of the elements in the welding current change sequence is small, making the value of the current smooth transition amount at this moment larger. Therefore, it shows that the current change monitored for the welding process at this moment is relatively smooth, the current is relatively stable, and the welding can weld the wire well.

[0064] At this point, the current smooth transition amount of each element in the welding current change sequence is obtained.

[0065] Step S003, label the welding cycle, and obtain the time flow difference at each moment by combining the corresponding current smooth transition sequence element value and the mean value of the element at the corresponding position; and obtain the automatic differential parameters of the current time period based on all time flow differences in the current time period and the time flow differences of the previous two adjacent time periods.

[0066] The current smooth transition amounts of all elements in the current subsequence are sorted according to the element order of the welding current change to obtain a current smooth transition sequence; a current smooth transition sequence can be obtained based on each welding cycle to characterize the stability of the welding current within the welding cycle.

[0067] In the process of welding metal wire, there are multiple welding cycles. As the welding time progresses, if the current smooth transition amount in the same stage of different welding cycles has a certain difference, it means that the stability of the welding current is disturbed, and the greater the change of the current smooth transition amount over time, the stronger the interference to the welding current. In the process of real-time automatic adjustment, the control intensity of the welding current should be enhanced to ensure the smooth operation of the current during welding, so that the automatic welding effect of the metal wire is better. Therefore, the welding cycles are marked with serial numbers in chronological order, and the serial numbers are recorded as time flow coefficients; the time flow difference at each moment is obtained by the difference between the value of each element of the current smooth transition sequence of all welding cycles and the mean of all elements in the corresponding position and the time flow coefficient, and the expression is:

[0068] , It represents the time flow difference at the pth moment of the welding cycle; Indicates the number of welding cycles; Indicates the time flow coefficient, which is used to reflect the importance of the welding cycle; represents the pth element in the current smooth transition sequence of the qth welding cycle; Represents the mean value of the pth element in the current smooth transition sequence of all welding cycles.

[0069] The greater the difference between the current steady transition amounts at the same time in different welding cycles, the worse the stability of the welding current becomes as time goes on during the welding process, making the difference between the current steady transition amounts at the same time, that is, The larger the value is, and as time goes by, the closer to the current moment, the worse the stability of the welding current is, and the greater the impact on the welding effect. Among them, the larger the value of the welding cycle number is, the closer it is to the current time. Therefore, the welding cycle number is used as the time flow coefficient to weight the smooth transition amount of the current in the welding cycle, so that the evaluation of the stability of the welding current during the welding process over time is more accurate. The welding current is controlled by this value, and the control effect is better, which has a better welding effect on the metal wire.

[0070] Furthermore, the mean of the time flow difference at all moments of the welding cycle is obtained as the time response difference of the welding cycle. The current of the processing machine is monitored, and in the process of automatic adjustment, when the current is regulated by the PID control algorithm, the differential parameter of the PID control is used to adjust the stability of the processing machine current. When the stability of the processing machine current is continuously reduced, the stability of the processing machine current can be increased by increasing the differential parameter, and vice versa.

[0071] The current time period is recorded as the time period to be adjusted, the previous time period of the time period to be measured is recorded as the first historical time period, and the previous time period of the first historical time period is recorded as the second historical time period. Since the closer the time period to be adjusted is, the greater the impact, the time response difference of the last welding cycle in the first historical time period and the second historical time period is calculated. The automatic differential parameters of the time period to be adjusted are obtained based on the difference in the time response difference of the last welding cycle in the first historical time period and the second historical time period and the automatic differential parameters of the first historical time period. The expression is:

[0072] , The automatic differential parameter representing the time period to be adjusted; Indicates the automated differential parameter for the first historical period; represents the time response difference of the first period of history; represents the difference in time response for the second period of history; Represents the sigmoid function.

[0073] The differential parameter, integral parameter and proportional parameter of the first time period are obtained by the extended response curve method in this embodiment. The extended response curve method is a well-known technology and will not be described in detail in this application.

[0074] When adjusting the current, if the time response difference of the first historical time period is greater than the time response difference of the second historical time period, that is, The value is large, indicating that the current stability of the processing machine tool is affected. Therefore, it is necessary to enhance the differential parameter of the first time period of the PID The value of The larger the value, the greater the instability suppression ability of the automatic welding system during the metal wire welding process, so that the welding of the metal wire can be carried out smoothly in the current time period, ensuring the automatic welding effect of the metal wire. Considering that in the adjustment process, excessively increasing the differential parameter of the PID control will extend the time it takes for the system to reach a stable state; excessively reducing the differential parameter of the PID will cause the system to respond more slowly to the deviation change, affecting the dynamic performance of the system. Therefore, the use of The function normalizes the data to ensure the adjusted value range.

[0075] At this point, the automatic differential parameters of the current time period are obtained.

[0076] Step S004, controlling the current of the processing machine tool in real time according to the automated differential parameters to complete automated welding.

[0077] For the automated differential parameters of the current of the processing machine tool in the current time period obtained above, as welding progresses, the automated differential parameters of each time period are continuously calculated, and then the automated welding PID current controller of the metal wire continuously receives the automated differential parameters, and then updates the differential parameters of the PID current controller. Based on the PID current controller, the current in the metal wire welding process is automatically controlled to make the current closer to the standard current, and based on this standard current, the metal wire is welded by the processing machine tool.

[0078] Based on the same inventive concept as the above method, an embodiment of the present invention also provides an automated wire processing machine for workpiece clamping, which includes a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, the steps of any one of the control methods of the above-mentioned automated wire processing machine for workpiece clamping are implemented.

[0079] It should be noted that the above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

[0080] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A control method for a workpiece clamping wire automatic processing machine tool, characterized in that: The method comprises the following steps: The metal wire is fixed and clamped on the welding table, and arranged horizontally and vertically for welding; a current sensor is installed on the processing machine tool to collect the current within a period of time to form a welding current sequence; The welding current sequence is transformed into the frequency domain to obtain the welding cycle of the welding current sequence, and the welding current sequence is divided into multiple current subsequences based on the welding cycle; the difference sequence of the calculated current subsequence is recorded as the current difference sequence, and the absolute value of the elements in the current difference sequence is taken to obtain the welding current change sequence; the elements in the current difference sequence are marked, and a window is constructed for each element in each current difference sequence, and the smooth continuity of each element is obtained according to whether the marks of adjacent elements in the window are the same; for each element of the welding current change sequence, a window of the same size as the current difference sequence is constructed, and the current smooth transition amount of each element is obtained according to the smooth continuity of each element of the current difference sequence and the coefficient of variation of the local window sequence of the elements at the same position of the welding current change sequence; The current smooth transition amounts of all elements of each current subsequence constitute a current smooth transition sequence, the welding cycles are marked with serial numbers in chronological order, and the time flow difference at each moment is obtained according to the difference between the value of each element of the current smooth transition sequence of all welding cycles and the mean value of all elements at the corresponding position and the serial number of the welding cycle; the time response difference is obtained based on the mean value of the time flow difference, and the automatic differential parameter of the current time period is obtained according to the difference between the time response differences of the two time periods before the current time period and the automatic differential parameter of the previous time period; The current is controlled in real time according to the automated differential parameters to complete automated welding.

2. The control method of a workpiece clamping wire automatic processing machine tool as claimed in claim 1, characterized in that: The method of performing frequency domain conversion on the welding current sequence to obtain the welding cycle of the welding current sequence and dividing the welding current sequence into a plurality of current subsequences based on the welding cycle is as follows: Input the welding current sequence, obtain the frequency domain of the welding current sequence based on Fourier transform, obtain the amplitude corresponding to each frequency in the frequency domain, record the frequency corresponding to the maximum amplitude as the first frequency, take the inverse of the first frequency as the welding cycle of the welding current sequence, and divide the welding current sequence according to the welding cycle to obtain several current sub-sequences.

3. The control method of a workpiece clamping wire automatic processing machine tool as claimed in claim 1, characterized in that: The method of marking the elements in the current differential sequence, constructing a window for each element in each current differential sequence, and obtaining the smooth continuity of each element according to whether the marks of adjacent elements in the window are the same is: Add a mark to the elements in the current differential sequence. When the value of the element is positive, it is marked as 1; when the value of the element is 0, it is marked as 0; when the value of the element is negative, it is marked as -1; A local window is obtained with each element as the center in the current difference sequence, and all elements in the local window are recorded as a local window sequence; Any element in the current differential sequence is recorded as the target element. If each element in the local window corresponding to the target element has the same mark value as the next element, the continuous value of the element is recorded as 1, otherwise the continuous value of the element is recorded as 0, and the continuous value of the last element is recorded as 0. The continuous values ​​of all elements in the local window are accumulated as the smooth continuity of the target element.

4. The control method of a workpiece clamping wire automatic processing machine tool as claimed in claim 1, characterized in that: The method for obtaining the current smooth transition amount of each element according to the smooth continuity of each element of the current difference sequence and the coefficient of variation of the local window sequence of the elements at the same position of the welding current change sequence is: The amount of current smooth transition is positively correlated with smooth continuity, and negatively correlated with the coefficient of variation of the local window sequence of the welding current change sequence elements.

5. The control method of a workpiece clamping wire automatic processing machine tool as claimed in claim 1, characterized in that: The method for obtaining the time flow difference at each moment according to the difference between the value of each element of the current smooth transition sequence of all welding cycles and the mean value of all elements at the corresponding position and the sequence number of the welding cycle is: The serial number of the welding cycle is recorded as the time flow coefficient; , It represents the time flow difference at the pth moment of the welding cycle; Indicates the number of welding cycles; represents the time flow coefficient; represents the pth element in the current smooth transition sequence of the qth welding cycle; Represents the mean value of the pth element in the current smooth transition sequence of all welding cycles.

6. The control method of a workpiece clamping wire automatic processing machine tool as claimed in claim 1, characterized in that: The method for obtaining the automatic differential parameter of the current time period according to the difference between the time response differences of the two time periods before the current time period and the automatic differential parameter of the previous time period is: Record the current time period as the time period to be adjusted, record the previous time period of the time period to be measured as the first historical time period, and record the previous time period of the first historical time period as the second historical time period; calculate the time response difference of the last welding cycle in the first historical time period and the second historical time period; The automatic differential parameter of the time period to be adjusted is obtained based on the difference in time response between the last welding cycle of the first historical time period and the second historical time period and the automatic differential parameter of the first historical time period.

7. The control method of a workpiece clamping wire automatic processing machine tool as claimed in claim 6, characterized in that: The expression of the automatic differentiation parameter is: , The automatic differential parameter representing the time period to be adjusted; Indicates the automated differential parameter for the first historical period; represents the time response difference of the first period of history; represents the difference in time response for the second period of history; Represents the sigmoid function.

8. The control method of a workpiece clamping wire automatic processing machine tool as claimed in claim 1, characterized in that: The method for real-time current control according to the automated differential parameter is: For the current time period, the automatic differential parameters of the current time period are calculated, the calculated automatic differential parameters are used to replace the existing differential parameters, the current of the current time period is input, and the current of the current time period is controlled based on the PID control algorithm.

9. The control method of a workpiece clamping wire automatic processing machine tool as claimed in claim 4, characterized in that: The expression of the current smooth transition amount is: , It represents the current smooth transition amount of the kth element in the welding current change sequence; Indicates the smooth continuity of the kth element in the periodic current difference sequence; represents the coefficient of variation of the kth element window sequence in the welding current variation sequence, Represents the adjustment factor.

10. An automated wire processing machine for clamping a workpiece, the machine comprising a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor implements a control method for an automated wire processing machine for clamping a workpiece as described in any one of claims 1 to 9 when executing the computer program.

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