Part turning chatter mark suppression method based on spindle current and related device

Abstract

The invention discloses a part turning chatter mark restraining method based on spindle current and a related device, and belongs to the technical field of turning machining. According to the method, the inhibition scheme of the turning chatter marks is determined by analyzing the generation reasons of the turning chatter marks; on the basis of the turning vibration mark restraining scheme, the spindle motor load and part machining information of a machining tool are collected; the radial cutting width is calculated through the spindle motor load and the part machining information; and the radial cutting width is fed back to a machine tool, machining parameters are adjusted according to changes of the radial cutting width, and turning vibration ripple suppression is achieved. According to the method, a chatter line generation rule is analyzed through a physical model, and a chatter line generation reason is determined; the radial cutting width is calculated based on a statistical analysis method, and the radial cutting width value is fed back to a machine tool, so that turning chatter mark suppression is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of turning machining, and relates to a method for suppressing turning vibration marks of parts based on spindle current and related devices. Background Art

[0002] Although automated machining improves machining efficiency, reduces manual intervention, and ensures product consistency. However, precisely due to the lack of manual intervention, abnormal situations during the machining process cannot be avoided, and the problem of occasional vibration marks on parts cannot be solved, resulting in a high rejection rate of parts and an increase in machining costs. To avoid similar problems, there are many active suppression methods and online monitoring methods used to systematically solve the problem of surface vibration marks of parts. Among them, the active suppression method has good effects in the new product trial production stage, but it cannot avoid the generation of vibration marks on parts during mass production; for the online monitoring method, it can timely detect abnormalities of parts during the machining process and avoid the outflow of parts with vibration marks, but the vibration marks on the surface of parts cannot be avoided after the abnormalities are detected, and the parts are scrapped. Especially for parts after heat treatment with high hardness and large differences, the problem of vibration marks is particularly prominent, especially the vibration marks generated on the surface of parts after finish machining cannot be effectively solved.

[0003] Generally, the machining parameters of mass-produced parts are fixed during the trial production stage (to ensure the stability of the process system). However, considering the changes in tool wear, thermal error, clamping stiffness, and uncertain factors during the machining process, the process system may become unstable, which in turn leads to the generation of vibration marks on the surface of parts. Once vibration marks are found, on-site personnel need to stop the line to check whether the process system is abnormal and retool for machining. In the case of heavy production tasks, it seriously affects the machining rhythm of the production line. Therefore, it is necessary to analyze the reasons for the generation of vibration marks in the finish machining stage according to the machining characteristics of parts and formulate corresponding measures to avoid the generation of vibration marks in the finish machining stage, so as to achieve the purpose of improving production efficiency and reducing production costs, which is urgently needed for automated production lines.

[0004] In summary, due to the lack of manual intervention in the current automated production line and factors such as high hardness of parts after heat treatment, turning vibration marks are likely to occur during the machining process of parts; there is an urgent need for a method for suppressing turning vibration marks to ensure part quality, reduce production costs, and improve the production efficiency of the production line. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for suppressing turning vibration marks of parts based on spindle current and related devices to solve the technical problem that turning vibration marks are likely to occur during the machining process in the prior art, affecting part quality and production efficiency.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] In the first aspect, the present invention provides a method for suppressing turning vibration marks of parts based on spindle current, including the following steps:

[0008] Based on the turning vibration pattern suppression solution, collect the spindle motor load and part machining information of the machining tool;

[0009] Calculate the radial cutting width through the spindle motor load and part machining information;

[0010] Feed back the radial cutting width to the machine tool, adjust the machining parameters according to the change of the radial cutting width, and achieve the suppression of turning vibration patterns.

[0011] Furthermore, the turning vibration pattern suppression solution is obtained by analyzing the causes of turning vibration patterns, and specifically includes:

[0012] The tool wears under the thermo-mechanical coupling effect. After the tool wears, it will cause an increase in the finishing allowance, thereby causing an increase in the turning force, making the process system unstable and generating vibration patterns; the calculation formula of the turning force is:

[0013] F = K·A (1)

[0014] Among them, K is the turning force coefficient; A is the turning area; F is the turning force;

[0015] Simplify the turning machining process system into a single-degree-of-freedom system, then the relationship between force and displacement is expressed as:

[0016]

[0017] Among them, f is the force; m is the mass; c is the damping; k is the stiffness; x is the displacement; is the velocity; is the acceleration;

[0018] Assume f = Fe iωt , x = Xe iωt , substitute into equation (2), and get:

[0019] (-ω 2 m + iωc + k)Xe iωt = Fe iωt (3)

[0020] Among them, t is the time; ω is the natural frequency of the system; i is the imaginary part of the complex number;

[0021] Then the relationship between the displacement X of the process system and the turning force F is expressed as:

[0022]

[0023] It can be obtained from equation (4) that as long as the turning force F fluctuates within the preset range, the fluctuation amount of the displacement X of the process system can be guaranteed to control the surface roughness of the part, thereby suppressing the vibration patterns;

[0024] Substitute the turning area A = b·h into Equation (5) to obtain:

[0025] F = K·b·h (5)

[0026] In the formula, b is the axial cutting width; h is the radial cutting width;

[0027] In mass production, if the axial cutting width b is changed, it will affect the production line rhythm. Therefore, the radial cutting width h is selected to control the turning force F.

[0028] Furthermore, the step of collecting the spindle motor load and part processing information in the turning vibration pattern suppression scheme specifically includes:

[0029] Since the workpiece to be machined is installed on the machine tool spindle through a chuck and the machine tool spindle is driven by a servo controller, the calculation formula for the motor load is:

[0030]

[0031] where T m is the motor load, K t is the torque coefficient, i u 、i v and i w are the phase currents;

[0032] The relationship between the turning force F and the motor load is expressed as:

[0033] F = T m R (7)

[0034] where R is the part diameter;

[0035] Collect part processing information; the part processing information includes the tool number, program block number, and spindle speed.

[0036] Furthermore, the step of calculating the radial cutting width through the spindle motor load and part processing information specifically includes:

[0037] Calculate the radial cutting width through the spindle motor load and part processing information;

[0038] According to the spindle motor load and part processing information, extract the time-frequency domain features to determine whether to reset the radial cutting width. The specific expression is:

[0039]

[0040] where T rms is the effective value of the time-frequency domain feature; T peak is the peak value of the time-frequency domain feature; T kurtosis is the kurtosis index of the time-frequency domain feature; Tcf is the margin factor; T min is the threshold lower difference; T max is the threshold upper difference;

[0041] When the calculation result of the extracted time-frequency domain feature exceeds the preset threshold upper difference or threshold lower difference, recalculate the radial cutting width.

[0042] Further, the step of recalculating the radial cutting width when the calculation result of the extracted time-frequency domain feature exceeds the preset threshold upper difference or threshold lower difference specifically includes:

[0043] When the calculation result of the extracted time-frequency domain feature exceeds the preset threshold upper difference, recalculate the radial cutting width. The specific calculation formula is:

[0044]

[0045] where h is the initial value of the radial cutting width; Δh is the change value of the radial cutting width; d ru is the upper difference of the rough-machined outer diameter; d rl is the lower difference of the rough-machined outer diameter; d is the actual value of the outer circle after rough machining; δ is the correction coefficient, δ ∈ [0.2, 0.7];

[0046] When the calculation result of the extracted time-frequency domain feature exceeds the preset threshold lower difference, recalculate the radial cutting width. The specific calculation formula is:

[0047]

[0048] where h is the initial value of the radial cutting width; Δh is the change value of the radial cutting width; h temp,i is the recalculated radial cutting width.

[0049] Further, it also includes:

[0050] Construct an evaluation index for the radial cutting width. The specific calculation formula of the evaluation index for the radial cutting width is:

[0051]

[0052] where C u is the index upper difference; C l is the index lower difference; T is the spindle load statistical index; μ is the target value; K c is the sample standard deviation;

[0053] Compare the sample value of the evaluation index of the adjusted radial cutting width during the machining process with the target value of the evaluation index when there is no vibration pattern. If the preset determination condition is met, execute the current adjustment method; if the requirement is not met, improve the adjustment method.

[0054] Further, the preset determination condition is as follows:

[0055]

[0056] where C u is the upper tolerance of the index; C l is the lower tolerance of the index.

[0057] In a second aspect, the present invention provides a part turning vibration mark suppression system based on spindle current, including:

[0058] A signal acquisition module, configured to acquire the spindle motor load and part machining information of the machining tool based on the turning vibration mark suppression scheme;

[0059] A radial cutting width calculation module, configured to calculate the radial cutting width through the spindle motor load and part machining information;

[0060] A feedback adjustment module, configured to feedback the radial cutting width to the machine tool, adjust the machining parameters according to the change of the radial cutting width, and achieve the suppression of turning vibration marks.

[0061] In a third aspect, the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the above method are implemented.

[0062] In a fourth aspect, the present invention provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, the steps of the above method are implemented.

[0063] Compared with the prior art, the present invention has the following beneficial effects:

[0064] The present invention discloses a part turning vibration mark suppression method and related device based on spindle current. By analyzing the influence laws of factors such as tool wear, clamping force fluctuation, and thermal error on the process system during the part turning machining process after heat treatment, the main reasons for the generation of vibration marks after part finish machining are found, and the turning vibration mark suppression scheme is determined; by collecting the spindle motor load and part machining information to calculate the change of the radial cutting width, and feeding back the change of the radial cutting width to the machine tool for adjustment, thereby realizing the suppression of turning vibration marks. The method of the present invention does not require the installation of sensors and is not restricted by the inconvenient installation of sensors and the harsh turning machining conditions. The change law of the turning force is obtained through the phase current of the spindle motor, and then the wear degree of the rough machining tool is reflected, solving the problem of occasional vibration marks during the machining process. And the present invention analyzes the vibration mark generation law through a physical model and determines the cause of the vibration mark generation; calculates the radial cutting width based on a statistical analysis method and feeds the radial cutting width value back to the machine tool. The obtained results can well avoid the generation of vibration marks during the machining process and have good engineering application value. Brief Description of the Drawings

[0065] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following accompanying drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related accompanying drawings can be obtained based on these accompanying drawings without creative efforts.

[0066] Figure 1 is a flowchart of the method of the present invention;

[0067] Figure 2 is a schematic diagram of the system of the present invention;

[0068] Figure 3 is a schematic diagram of the turning process of the embodiment of the present invention;

[0069] Figure 4 is a schematic diagram of the machine tool spindle and the workpiece of the embodiment of the present invention.

[0070] Among them, 1, finish machining surface; 2, rough machining surface; 3, tool position at time t; 4, tool position at time t + 1; 5, workpiece to be machined; 6 - spindle. Detailed Embodiments

[0071] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0072] The following detailed descriptions are all exemplary descriptions, aiming to provide further detailed descriptions of the present invention. Unless otherwise specified, all technical terms adopted by the present invention have the same meaning as commonly understood by those of ordinary skill in the art to which this application belongs. The terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the exemplary embodiments of the present invention.

[0073] See Figure 1 , an embodiment of the present invention discloses a method for suppressing turning vibration marks of parts based on spindle current, including the following steps:

[0074] S1. By analyzing the causes of turning vibration marks, determine the suppression scheme for turning vibration marks;

[0075] S101. Analysis of the causes of turning machining vibration marks

[0076] During the external turning machining process, when the tool contacts the workpiece, cutting force will be generated, which will in turn cause vibration. The vibration during the machining process will cause displacement changes in the weak links of the process system (the parts with relatively weak system stiffness), such as Figure 3As shown in the figure, it affects the surface roughness of the part, and vibration marks will be generated in severe cases. Taking the turning of the outer diameter of the part as an example, the cutting force F can be expressed by equation (1):

[0077] F = K·A(1)

[0078] Where: K is the cutting force coefficient, which is determined by the tool and workpiece materials; A is the cutting area, which is determined by the axial and radial cutting widths.

[0079] Generally, vibration causes a large change in the displacement between the tool and the workpiece. Especially during the rough machining process, the large cutting parameters lead to vibration, which causes an increase in the unevenness of the part surface. When finishing machining, the uneven surface makes the cutting parameters different, and self-excited vibration is likely to occur, and the vibration marks are reproduced on the part surface. This phenomenon is particularly prominent during the machining process of heat-treated parts. In addition, the tool wears under the action of thermo-mechanical coupling. After the tool wears, it will cause an increase in the finishing allowance, and the cutting force will increase accordingly, and then the process system becomes unstable and vibration marks are generated. In severe cases, the tool breaks.

[0080] S102, determining the turning vibration mark suppression scheme

[0081] At present, the solutions to vibration marks mostly involve increasing the rigidity of the process system, such as methods like auxiliary supports and increasing the clamping force of the part and the tool. This solution can well guarantee the part quality during the trial production stage. However, during the mass production stage, the differences between parts and the changes in tool conditions are the key factors affecting the generation of vibration marks. Especially in the automatic production line, when the process system stability is in a critical state, the vibration marks of the parts cannot be guaranteed, and defective products are likely to be produced in batches.

[0082] The present invention simplifies the process system into a single-degree-of-freedom system, and the relationship between force and displacement is expressed by equation (2):

[0083]

[0084] Where: f is the force; m is the mass; c is the damping; k is the stiffness; x is the displacement; is the velocity; is the acceleration.

[0085] Assume f = Fe iωt , x = Xe iωt , substituting into equation (2), it can be expressed by equation (3):

[0086] (-ω 2 m + iωc + k)Xe iωt = Fe iωt (3)

[0087] Where: t is the time; ω is the natural frequency of the system; i is the imaginary part of the complex number.

[0088] Therefore, the relationship between the displacement of the process system and the turning force can be expressed by Equation (4):

[0089]

[0090] It can be seen from Equation (4) that when the process system remains unchanged, as long as the force F fluctuates within a certain range, the fluctuation of the displacement X can be ensured, so that the unevenness of the part surface meets the roughness requirements, thereby suppressing the vibration pattern and indirectly ensuring the system stability.

[0091] To sum up, the core of suppressing the vibration pattern lies in controlling the magnitude of the turning force. Considering that the turning area A = b·h, the turning force F can be expressed by Equation (5):

[0092] F = K·b·h (5)

[0093] Where: b is the axial cutting width; h is the radial cutting width.

[0094] In mass production, changing the axial cutting width b will affect the production line rhythm. Therefore, choosing to change the radial cutting width h to control the change range of the force F is the best solution.

[0095] S2. Based on the suppression scheme of turning vibration pattern, collect the spindle motor load and part processing information of the processing machine tool;

[0096] As can be seen from the above analysis, by controlling the radial cutting width to ensure that the turning force fluctuates within a certain range, the stability of the process system is ensured, thus achieving the purpose of suppressing the vibration pattern. However, during the processing process, the change of the turning force cannot be sensed, nor can it be judged whether the vibration pattern occurs.

[0097] Considering that the workpiece is directly installed on the lathe spindle through the chuck, as Figure 4 shown, the lathe spindle is driven by a servo controller. Therefore, the relationship between the motor load and the three-phase current of the motor can be expressed by Equation (6):

[0098]

[0099] Where: T m is the motor load, K t is the torque coefficient, i u 、i v 、i w are the phase currents.

[0100] The relationship between the turning force F and the motor load can be expressed by Equation (7):

[0101] F = T m R (7)

[0102] Where: R is the part diameter.

[0103] Therefore, combining with equation (5), it can be known that the change of the radial cutting width in the rough machining process is reflected by monitoring the change of the motor load. In addition, the part is divided into rough and finish machining processes. Different tools are used in each machining process, and there is a tool change process. Continuously collecting the motor load affects the judgment and occupies memory. It is also necessary to collect machining process information such as tool number, program segment number, and spindle speed. Finally, using the TCP / IP protocol, the machining information and the spindle motor load signal are obtained through the numerical control system, and the collected information is saved to the folder at the specified path.

[0104] S3. Calculate the radial cutting width from the spindle motor load and the part machining information;

[0105] Based on the analysis of S102, it can be known that choosing to change the radial cutting width can suppress the generation of accidental vibration marks. Considering the influence of the wear of the rough machining tool on the radial cutting width in the actual machining, the motor load in the rough machining process is collected in real time and the time-frequency domain characteristics are extracted to judge whether it is necessary to reset the radial cutting width. The judgment method can be expressed by equation (8).

[0106]

[0107] Among them, T rms is the effective value of the time-frequency domain characteristics; T peak is the peak value of the time-frequency domain characteristics; T kurtosis is the kurtosis index of the time-frequency domain characteristics; T cf is the margin factor; T min is the lower difference of the threshold; T max is the upper difference of the threshold;

[0108] When the calculation result of the extracted time-frequency domain characteristic index exceeds the upper and lower differences of the set threshold (the upper and lower differences of the threshold are set according to experience), the radial cutting width needs to be recalculated. When it exceeds the upper difference of the set threshold, the calculation method of the radial cutting width can be expressed by equation (9):

[0109]

[0110] Among them, h is the initial value of the radial cutting width; Δh is the change value of the radial cutting width; d ru is the upper difference of the rough machining outer diameter; d rl is the lower difference of the rough machining outer diameter; d is the actual value of the outer diameter after rough machining; δ is the correction coefficient, δ ∈ [0.2, 0.7];

[0111] When it exceeds the lower difference of the set threshold, the calculation method of the radial cutting width can be expressed by equation (10):

[0112]

[0113] S4. Feed the radial cutting width back to the machine tool, adjust the machining parameters according to the change of the radial cutting width, and achieve the suppression of turning vibration marks.

[0114] S5. Evaluation of vibration mark suppression strategy

[0115] During the machining process, quality control is the key to ensuring the assessable consistency of product quality (low scrap rate, high qualification rate), and appropriate evaluation indicators are the key elements for evaluating and monitoring product quality. Considering that the vibration marks mentioned in this article are sporadic phenomena, the change of the radial cutting width is judged by real-time monitoring of the spindle load change for suppression. Therefore, the deviation between the sample value and the target value is used for judgment, which can be expressed by formula (11).

[0116]

[0117] In the formula: C u is the upper tolerance of the index; C l is the lower tolerance of the index; T is the spindle load statistical index; μ is the target value; K c is the sample standard deviation (calculated by 6 sigma).

[0118] Compare the sample value of the evaluation index of the adjusted radial cutting width during the machining process with the target value of the evaluation index when there are no vibration marks, which can be expressed by formula (12).

[0119]

[0120] If the judgment condition is met, execute the current adjustment method; if the requirement is not met, the adjustment method needs to be improved.

[0121] See Figure 2 , an embodiment of the present invention discloses a part turning vibration mark suppression system based on spindle current, including a signal acquisition module, a radial cutting width calculation module, and a feedback adjustment module.

[0122] Among them, the signal acquisition module is used to collect the spindle motor load and part machining information of the machining tool based on the vibration mark suppression scheme of turning; the radial cutting width calculation module is used to calculate the radial cutting width through the spindle motor load and part machining information; the feedback adjustment module is used to feed the radial cutting width back to the machine tool and adjust the machining parameters according to the change of the radial cutting width to achieve the suppression of turning vibration marks.

[0123] In one embodiment of the present invention, a computer device is provided, which includes a processor and a memory. The memory is used to store a computer program, and the computer program includes program instructions. The processor is used to execute the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, and is suitable for implementing one or more instructions. Specifically, it is suitable for loading and executing one or more instructions in the computer storage medium to implement the corresponding method flow or corresponding function. The processor described in the embodiment of the present invention can be used for the operation of the method for suppressing part turning vibration marks based on spindle current.

[0124] The present invention also provides a storage medium, specifically a computer-readable storage medium (Memory). The computer-readable storage medium is a memory device in a computer device and is used to store programs and data. It can be understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and, of course, the extended storage medium supported by the computer device. The computer-readable storage medium provides a storage space, and the operating system of the terminal is stored in this storage space. And, one or more instructions suitable for being loaded and executed by the processor are also stored in this storage space. These instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. One or more instructions stored in the computer-readable storage medium can be loaded and executed by the processor to implement the corresponding steps of the method for suppressing part turning vibration marks based on spindle current in the above embodiment.

[0125] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memory, CD-ROM, optical memory, etc.) that contain computer-usable program code.

[0126] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0127] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means that implement the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0128] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0129] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: still can modify the specific implementation manners of the present invention or make equivalent substitutions, and any modification or equivalent substitution that does not depart from the spirit and scope of the present invention shall be covered by the protection scope of the claims of the present invention.

Claims

1. A method for suppressing vibration marks in part turning based on spindle current, characterized in that, It includes the following steps: Based on the suppression scheme of turning vibration marks, collect the spindle motor load and part machining information of the processing machine tool; Calculate the radial cutting width from the spindle motor load and part machining information; Feed back the radial cutting width to the machine tool, and adjust the machining parameters according to the change of the radial cutting width to achieve the suppression of turning vibration marks.

2. A method for suppressing part turning vibration marks based on spindle current according to claim 1, characterized in that, The suppression scheme of the turning vibration marks is obtained by analyzing the causes of the generation of turning vibration marks, and specifically includes: The tool wears under the action of thermal-mechanical coupling. After the tool wears, it will cause an increase in the finishing allowance, thereby causing an increase in the turning force, making the process system unstable and generating vibration marks; the calculation formula of the turning force is: F = K·A (1) Wherein, K is the turning force coefficient; A is the turning area; F is the turning force; Simplify the turning processing process system into a single-degree-of-freedom system, then the relationship between force and displacement is expressed as: Where, f is the force; m is the mass; c is the damping; k is the stiffness; x is the displacement; is the velocity; is the acceleration; Assume f = Fe iωt , x = Xe iωt , substituting into equation (2), we get: (-ω 2 m + iωc + k)Xe iωt =Fe iωt (3) Wherein, t is time; ω is the natural frequency of the system; i is the imaginary part of the complex number; Then the relationship between the displacement X of the process system and the turning force F is expressed as: It can be obtained from formula (4) that as long as the turning force F fluctuates within a preset range, the fluctuation amount of the displacement X of the process system can be ensured to control the surface roughness of the part, thereby suppressing the vibration marks; Substitute the turning area A = b·h into formula (5) to get: F = K·b·h (5) In the formula, b is the axial cutting width; h is the radial cutting width; In mass production, if the axial cutting width b is changed, it will affect the production line rhythm. Therefore, choose to change the radial cutting width h to control the turning force F.

3. A method for suppressing vibration marks in part turning based on spindle current according to claim 1, characterized in that, The step of collecting the spindle motor load and part machining information in the suppression scheme based on turning vibration marks specifically includes: Since the workpiece to be machined is installed on the machine tool spindle through a chuck, and the machine tool spindle is driven by a servo controller, the calculation formula of the motor load is: Among them, T m is the motor load, K t is the torque coefficient, i u , i v and i w are the phase currents; The relationship between the turning force F and the motor load is expressed as: F = T m / R (7) Wherein, R is the part diameter; Collect part machining information; the part machining information includes the tool number, program segment number, and spindle speed.

4. A method for suppressing part turning vibration marks based on spindle current according to claim 1, characterized in that The step of calculating the radial cutting width from the spindle motor load and part machining information specifically includes: Calculate the radial cutting width from the spindle motor load and part machining information; Extract the time-frequency domain features according to the spindle motor load and part machining information to judge whether the radial cutting width needs to be reset, and the specific expression is: Among them, T rms is the effective value of the time-frequency domain feature; T peak is the peak value of the time-frequency domain feature; T kurtosis is the kurtosis index of the time-frequency domain feature; T cf is the margin factor; T min is the lower difference of the threshold; T max is the upper difference of the threshold; When the calculation result of the extracted time-frequency domain features exceeds the preset upper threshold or lower threshold, recalculate the radial cutting width.

5. A method for suppressing vibration marks in part turning based on spindle current according to claim 4, characterized in that, The step of recalculating the radial cutting width when the calculation result of the extracted time-frequency domain features exceeds the preset upper threshold or lower threshold specifically includes: When the calculation result of the extracted time-frequency domain features exceeds the preset upper threshold, recalculate the radial cutting width, and the specific calculation formula is: Among them, h is the initial radial cutting width value; Δh is the change value of the radial cutting width; d ru is the upper deviation of the rough-machined outer diameter; d rl is the lower deviation of the rough-machined outer diameter; d is the actual value of the outer diameter after rough machining; δ is the correction coefficient, and δ ∈ [0.2, 0.7]; When the calculation result of the extracted time-frequency domain features exceeds the preset lower threshold, recalculate the radial cutting width, and the specific calculation formula is: Among them, h is the initial radial cutting width value; Δh is the change value of the radial cutting width; h temp,i is the recalculated radial cutting width.

6. A method for suppressing the turning vibration marks of parts based on the spindle current according to claim 1, characterized in that, It also includes: Construct an evaluation index for the radial cutting width, and the specific calculation formula of the evaluation index for the radial cutting width is: Among them, C u is the upper tolerance of the index; C l is the lower tolerance of the index; T is the statistical index of the spindle load; μ is the target value; K c is the sample standard deviation; Compare the sample value of the evaluation index of the adjusted radial cutting width during the machining process with the target value of the evaluation index when there are no vibration marks. If the preset determination condition is met, execute the current adjustment method; If the requirements are not met, improve the adjustment method.

7. A method for suppressing part turning vibration marks based on spindle current according to claim 6, characterized in that The preset determination conditions are as follows: Among them, C u is the upper tolerance of the index; C l is the lower tolerance of the index.

8. A part turning vibration mark suppression system based on spindle current, characterized in that, Including: A signal acquisition module, configured to collect the spindle motor load and part processing information of the processing machine tool based on the turning vibration pattern suppression scheme; A radial cutting width calculation module, configured to calculate the radial cutting width through the spindle motor load and part processing information; A feedback adjustment module, configured to feedback the radial cutting width to the machine tool, adjust the processing parameters according to the change of the radial cutting width, and achieve the suppression of turning vibration patterns.

9. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, the steps of the method according to any one of claims 1-7 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, the steps of the method according to any one of claims 1-7 are implemented.

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