Auxiliary wire feeding regulation system and method of coaxial laser fuse cladding equipment

Abstract

The application discloses a kind of coaxial laser fuse cladding equipment auxiliary wire feeding regulation system and method.There is / are information input module for inputting the standard parameter of cladding equipment when cladding operation;Information receiving module is used to receive the molten pool camera equipment collected molten pool image information of cladding equipment when cladding operation;Information processing module, according to the molten pool image information and standard parameter calculation cladding operation actual parameter, compare actual parameter and standard parameter in predetermined deviation range, form control instruction for controlling the cladding equipment, and display relevant parameters in regulation interface.The application and coaxial laser fuse cladding equipment, molten pool camera equipment work cooperatively, by the judgment standard in auxiliary wire feeding regulation system, according to select corresponding solution strategy, improve the stability and safety of cladding equipment wire feeding system, to improve its production efficiency and production quality, to adapt to long time work plan and automation closed loop control demand.

Description

Technical Field

[0001] This invention relates to the field of laser cladding technology, specifically to an auxiliary wire feeding control system and method for coaxial laser cladding equipment, used for automatic control of process parameters during laser cladding to improve forming quality and efficiency. Background Technology

[0002] Coaxial laser cladding technology centers the filament and aligns it perpendicular to the processing surface. Utilizing different laser coupling techniques, it ensures the laser beam is focused on the filament's central axis, forming a molten pool at the focal point to complete the cladding process. This technology uses a laser as the heat source, allowing for more precise control of heat input and forming accuracy, and can handle more complex cladding environments. Furthermore, compared to electric arcs, laser cladding is more stable, with less spatter and explosion, resulting in fewer defects. Since lasers do not need to consider the material's conductivity, cladding materials can be chosen not only as metals but also as non-metals such as ceramics and plastics. Compared to off-axis laser methods, coaxial lasers suffer from less severe issues with scanning directionality and uneven heating, allowing for more complex forming paths.

[0003] However, as a novel cladding technology, coaxial laser wire cladding has some imperfections, one of which is the wire feeding control during the cladding process. Unlike the wire feeding control technology of arc wire cladding, the wire feeding system in coaxial laser wire cladding is relatively independent and does not have a strong correlation with the laser cladding system, lacking effective negative feedback regulation. Furthermore, research on wire feeding control in coaxial laser wire cladding scenarios is limited, leaving many gaps in our understanding. We have found that due to the unique laser coupling method, coaxial laser wire cladding requires a high wire elongation length, especially for long-duration continuous cladding tasks. Accumulated errors over time can lead to various problems in the cladding process, requiring manual intervention and reducing efficiency. It also carries potential risks such as decreased cladding quality and safety issues.

[0004] Currently, there is no complete system for adjusting wire elongation and feed speed during the wire melting process; most methods rely on operator experience. Operators primarily rely on real-time monitoring of the molten pool using a camera. While current molten pool image acquisition technology can obtain real-time, clear, and stable images and videos, it often only provides observation capabilities. Therefore, the current technology has the following shortcomings:

[0005] Operators can only observe the image or video of the molten pool with the naked eye and then make judgments on the cladding based on experience. Such judgments are often accompanied by large errors. Moreover, the time that passes between the operator's mental processing and action leads to a relative lag in adjustment, all of which will affect the stability of the cladding and are not conducive to ensuring product quality. Summary of the Invention

[0006] The purpose of this invention is to provide an auxiliary wire feeding control system and method for a coaxial laser cladding equipment, which can ensure the stability of the cladding process and meet the accuracy requirements of the cladding path, while reducing human interference and improving cladding efficiency.

[0007] The present invention adopts the following technical solution:

[0008] An auxiliary wire feeding control system for a coaxial laser cladding device includes:

[0009] The information input module is used to input the standard parameters of the cladding equipment during cladding operations;

[0010] The information receiving module is used to receive image information of the molten pool during cladding operations.

[0011] The information processing module calculates the actual parameters during the cladding operation based on the molten pool image information and standard parameters, compares the actual parameters with the standard parameters within a predetermined deviation range, and generates control commands for controlling the cladding equipment.

[0012] The information sending module is used to send the control commands to the cladding equipment.

[0013] Furthermore, the information processing module includes:

[0014] The real-time monitoring module is used to display the standard parameters, molten pool image information, and actual parameters;

[0015] The background safety protection module is used to compare actual parameters and standard parameters within a predetermined deviation range to identify abnormal situations during the wire feeding process of the cladding equipment and generate corresponding control commands.

[0016] The adaptive wire feeding control module is used to compare actual parameters with standard parameters within a predetermined deviation range, thereby generating control commands to adjust the wire dry elongation before melting and the wire feeding speed during melting.

[0017] The cladding equipment is a coaxial laser wire cladding equipment, which has walking, laser control and wire feeding control functions;

[0018] The molten pool image information is acquired by the molten pool camera device and transmitted to the information receiving module;

[0019] The information processing module segments the molten pool image information into pixel analysis regions for the wire part, the molten pool part, and the cladding layer part, and uses pixel image analysis to identify and analyze each pixel analysis region.

[0020] An auxiliary wire feeding control method for a coaxial laser cladding device includes the following steps:

[0021] 1) Obtain the standard parameters of the cladding equipment during cladding operations;

[0022] 2) Obtain image information of the molten pool during cladding operations;

[0023] 3) Analyze the molten pool image information and standard parameters to obtain the actual parameters during the cladding operation, and display the molten pool image information, standard parameters, and actual parameters in real time;

[0024] 4) Compare the actual parameters with the standard parameters within the predetermined deviation range, identify abnormal situations in the wire feeding process of the cladding equipment, and generate and send corresponding control commands to the cladding equipment;

[0025] 5) Compare the actual parameters with the standard parameters within the predetermined deviation range, generate and send control commands to the cladding equipment to adjust the wire dry elongation before cladding and the wire feeding speed during cladding.

[0026] Furthermore, in step 1, the standard parameters include:

[0027] True diameter D of the wire r Standard width of cladding channel W r0 Theoretical wire feeding speed V f0 Standard dry elongation length L of wire before melting r10 The standard length L of unmelted wire during the melting process. r20 , wire feed speed safety fluctuation coefficient F v 1. Safe fluctuation range of wire elongation L s Parameter L for adjusting the dry elongation of the filament a ;

[0028] In step 3, the molten pool image information and standard parameters are analyzed to obtain the actual parameters during the cladding operation, including:

[0029] 3-1) Pixelate the image in the molten pool image information, and divide the pixel analysis area of ​​the wire part, the pixel analysis area of ​​the molten pool part and the pixel analysis area of ​​the cladding layer part in the pixelated image interface;

[0030] 3-2) Obtain the brightness feature parameters of each pixel analysis region to get the number n of bright regions in the molten pool region. p ;

[0031] 3-3) Obtain the image parameters of each pixel analysis region to obtain the wire image diameter D. i Wire image without molten wire, dry elongation length L i1 The length L of the unmelted wire during the melting process. i2 and the reference area A of the molten pool image i ;

[0032] 3-4) Obtain the conversion ratio coefficient

[0033] 3-5) Calculate the actual dry elongation L of the filament before melting based on the scaling factor P and image parameters. r1 The actual length L of the unmelted wire during the melting process. r2 Actual reference area A of the molten pool r And the actual steady-state reference area A of the molten pool r0 Actual average wire feeding speed V fr .

[0034] Abnormal situations in step 4 include abnormal wire feeding, the bottom end of the wire detaching from the surface of the cladding channel and forming a ball, the wire swing amplitude exceeding the predetermined value during the wire melting process, and failure to melt the wire.

[0035] The steps for identifying the wire feeding abnormality and generating control commands include:

[0036] 4-11) Obtain standard parameters and actual parameters;

[0037] 4-12) Standard length L of unmelted wire when calibrating the fuse r20 ;

[0038] Where T w2 and T w1 For normal fuse operation, select the times at time node 2 and time node 1, L r2i This represents the actual elongation of the unmelted wire during the melting point between time nodes 2 and 1.

[0039] 4-13) When L r2 >L r20 +L s or L r2 <L r20 -L s At that time, it was determined that "the dry elongation of the filament is abnormal" and a control command to "stop moving, glazing and feeding the filament" was sent to the cladding equipment.

[0040] 4-14) When V fr >(1+F v V f0 or V fr<(1-F v V f0 When the error occurs, it is determined that the "wire feeding speed" is abnormal, and a control command to "stop moving, light output and wire feeding" is sent to the cladding equipment.

[0041] The steps for identifying and forming control commands regarding the bottom end of the filament detaching from the cladding surface and forming a ball include:

[0042] 4-21) Choose between normal regulation mode or conservative regulation mode;

[0043] 4-22) Obtain standard parameters and actual parameters;

[0044] 4-23) When n P =2, or L r2 <L r20 -L s At that time, it was determined to be an "abnormal state of the cladding channel";

[0045] 4-24) When an "abnormal state of the cladding channel" occurs;

[0046] If the conservative control mode is selected in step 4-21, a control command of "stop moving, light output and wire feeding" is sent to the cladding equipment.

[0047] If the normal control mode is selected in step 4-21, a "fast wire feeding" control command is sent to the cladding equipment, which increases the wire feeding speed V of the cladding equipment. f Adjusted to V f =1.5V f0 Then, when n P =1 and L r2 >L r20 -L s Then, a "normal wire feeding" control command is sent to the cladding equipment, which increases the wire feeding speed V of the cladding equipment. f Adjusted to V f =V f0 .

[0048] The steps for identifying and generating control commands when the wire oscillation amplitude exceeds a predetermined value during the wire melting process include:

[0049] 4-31) Choose between normal regulation mode or conservative regulation mode;

[0050] 4-32) Obtain standard parameters and actual parameters;

[0051] 4-33) Calculate the safe swing angle θ s ;

[0052] According to θ s Define a safe swing area in the pixelated image interface, and then determine the wire diameter D.r Delineate stable zones;

[0053] 4-34) When all pixels of the wire material feature are in the stable region, it is determined as "no swaying";

[0054] When some pixels of the wire material feature are within the safe swing area, and no pixels are outside the stable area and the safe swing area, it is judged as "normal swing".

[0055] When some pixels of the wire material feature are outside the stable region and the safe swing region, it is judged as "abnormal swing".

[0056] 4-35) When "abnormal oscillation" occurs;

[0057] If the conservative control mode is selected in step 4-31, a control command of "stop moving, light output and wire feeding" is sent to the cladding equipment.

[0058] If the normal control mode is selected in step 4-31, a "decelerate wire feeding" control command is sent to the cladding equipment to reduce the wire feeding speed V of the cladding equipment. f Adjusted to V f =0.9V f0 Then, when the pixels of the wire feature are in the "no wobbling" state, a "normal wire feeding" control command is sent to the cladding equipment, increasing the wire feeding speed V. f Adjusted to V f =V f0 .

[0059] In step 5, comparing the actual parameters and standard parameters within a predetermined deviation range, generating and sending a control command to the cladding equipment to adjust the wire dry elongation before cladding, includes the following steps:

[0060] 5-11) Obtain standard parameters and actual parameters;

[0061] 5-12) Obtain the image distance L from the bottom of the guide wire nozzle to the cladding surface from the image parameters of each pixel analysis region. di The actual distance from the bottom of the guide wire nozzle to the cladding surface is obtained by calculation.

[0062] 5-13) When L dr >L r10 +L a or L dr <L r10 -L a At that time, a control command for "start path coordinate value offset" is sent to the cladding equipment, and the cladding equipment moves the laser cladding head so that L dr =L r10Then, a control command to "stop path coordinate value offset" is sent to the cladding equipment.

[0063] 5-14) When L r10 -L a <L dr <L r10 +L a hour,

[0064] If L dr >L r10 Then, a "normal wire feeding" control command is sent to the cladding equipment at a wire feeding speed V. f0 Continue feeding the wire until L r1 =L dr Then, a "stop wire feeding" control command is sent to the cladding equipment.

[0065] If L dr <L r10 Then, a "normal wire drawing" control command is sent to the cladding equipment, with a wire drawing speed V. f0 Continue drawing the fibers until L is reached. r1 =L dr Then, a "stop wire drawing" control command is sent to the cladding equipment.

[0066] In step 5, comparing the actual parameters and standard parameters within a predetermined deviation range, generating and sending a control command to the cladding equipment to adjust the wire feeding speed during the cladding process, includes the following steps:

[0067] 5-21) Obtain standard parameters and actual parameters;

[0068] 5-22) When L r2 >L r20 +L a Send a "speed up wire feeding" control command to the cladding equipment to increase the wire feeding speed V of the cladding equipment. f Adjusted to V f =1.2V f0 until L r2 =L r20 Then, send a "normal wire feeding" control command to the cladding equipment; adjust the wire feeding speed V. f Adjusted to V f =V f0 ;

[0069] 5-23) When L r2 <L r20 -L a Send a "decelerate wire feeding" command to the cladding equipment to reduce the wire feeding speed V of the cladding equipment. f Adjusted to V f =0.9V f0until L r2 =L r20 Then, send a "normal wire feeding" control command to the cladding equipment; adjust the wire feeding speed V. f Adjusted to V f =V f0 .

[0070] This invention addresses the current imperfect wire feeding control design of coaxial laser filament cladding equipment. It utilizes molten pool image acquisition technology and pixel image analysis technology, and combines common problems and needs encountered in the cladding process of coaxial laser filament cladding equipment to design a set of practical and simple analysis methods and control means, which have high practical value and feasibility.

[0071] The beneficial effects of this invention are as follows:

[0072] By observing the change in wire elongation when the wire is fused (or not fused), the fused wire condition can be judged. Combined with the comparison of the reference area of ​​the molten pool with its steady state, it is possible to more reasonably and intuitively judge whether the matching between wire elongation and wire feeding speed is normal.

[0073] It has a certain degree of self-adjustment capability and good negative feedback adjustment function; and based on real-time and quantitative data, it can make timely adjustments for common situations, which can greatly improve stability and security.

[0074] During operation, it does not require much human intervention and has good adaptive adjustment capabilities. Therefore, it can significantly improve the production efficiency and quality of coaxial laser filament cladding equipment, and can also adapt to long-term work plans, making it easy to achieve automated closed-loop control production in the future. Attached Figure Description

[0075] Figure 1 This is a schematic diagram of the working scenario of an auxiliary wire feeding control system according to the present invention.

[0076] Figure 2 This is a schematic diagram of the viewfinder area of ​​the molten pool camera in this invention.

[0077] Figure 3 This is a schematic diagram of the image pixel analysis area in this invention.

[0078] Figure 4 This is a schematic diagram of the unfused screen in this invention.

[0079] Figure 5 This is a schematic diagram of the normal fuse screen in this invention.

[0080] Figure 6 This is a schematic diagram of the molten droplet pattern formed at the end of the wire in this invention.

[0081] Figure 7 This is a schematic diagram of the safe swing area of ​​the wire during the melting process in this invention.

[0082] Figure 8 This is a schematic diagram illustrating the actual wire feeding speed measurement principle in this invention.

[0083] In the diagram: 1. Display screen; 2. Computer host; 3. Coaxial laser cladding head; 4. Electrical control cabinet for coaxial laser cladding equipment; 5. Molten pool camera equipment; 6. Mounting bracket; 7. Guide nozzle;

[0084] 8. Laser; 9. Wire material; 10. Cladding layer; 11. Substrate; 12. Molten pool; 13. Molten droplet;

[0085] 14. Pixel analysis area of ​​the wire material; 15. Pixel analysis area of ​​the molten pool; 16. Pixel analysis area of ​​the cladding layer;

[0086] 17. The distance L between the bottom of the guide tip and the cladding surface d 18. Wire dry elongation length L when not fused r1 19. Length L of unmelted wire during melting r2 20. Safe swing angle θ s 21. Safe swing zone;

[0087] 22. Actual wire feeding speed measurement point 1; 23. Actual wire feeding speed measurement point 2; 24. Actual wire feeding speed measurement interval L t . Detailed Implementation

[0088] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0089] Example 1:

[0090] like Figure 1 and Figure 2 As shown, this invention provides an auxiliary wire feeding control system for a coaxial laser cladding equipment. This system works in conjunction with the coaxial laser cladding equipment and the molten pool camera equipment. The auxiliary wire feeding control system is installed in a computer host 2, which can transmit data with the coaxial laser cladding equipment and the molten pool camera equipment 5.

[0091] The auxiliary wire feeding control system mainly includes an information input module, an information receiving module, an information processing module, and an information sending module. The information input module is used to input the standard parameters of the cladding equipment during cladding operations; the information receiving module is used to receive molten pool image information collected by the molten pool camera equipment during cladding operations; the information processing module calculates the actual parameters during cladding operations based on the molten pool image information and the standard parameters, compares the actual parameters with the standard parameters within a predetermined deviation range, and generates control commands for controlling the cladding equipment (laser control and wire feeding control functions), and displays the relevant parameters on the control interface, including standard parameters and actual parameters; the information sending module is used to send control commands to the cladding equipment.

[0092] The information processing module mainly consists of three parts: a real-time monitoring module, a background safety protection module, and an adaptive wire feeding control module. The real-time monitoring module includes a display screen 1 connected to the computer host 2, used to display standard parameters, molten pool image information, and actual parameters. The background safety protection module compares the actual parameters with the standard parameters within a predetermined deviation range to identify abnormalities in the wire feeding process of the cladding equipment and generates corresponding control commands. The adaptive wire feeding control module compares the actual parameters with the standard parameters within a predetermined deviation range, thereby generating control commands to adjust the wire elongation before cladding and the wire feeding speed during cladding.

[0093] In this embodiment, the cladding equipment is a coaxial laser wire cladding device, which is an external device. It is equipped with a moving mechanism, a cladding unit, a laser and wire feeding control unit, and has normal control functions for movement, laser operation, and wire feeding. It can also receive control commands from an auxiliary wire feeding control system. Combined with... Figure 1 As shown, the cladding equipment includes a coaxial laser filament cladding head 3 and a coaxial laser filament cladding equipment control cabinet 4. The control unit of the coaxial laser filament cladding equipment is located in the coaxial laser filament cladding equipment control cabinet 4 and can receive external signals for regulation.

[0094] In this embodiment, the molten pool camera device 5 is an external device, equipped with a laser light source, a filter, an industrial camera, and an adjustable mounting bracket 6. The molten pool camera device 5 has the function of stably and in real-time collecting molten pool images and can transmit the data to the auxiliary wire feeding control system. The illumination laser light source used for the molten pool camera in the molten pool camera device 5 must be distinguished from the cladding laser light source of the coaxial laser wire cladding equipment; the two laser wavelengths have a certain difference to meet the requirement of non-interference. The filter used for the molten pool camera in the molten pool camera device 5 can eliminate the influence of other wavelengths of light to improve the quality of the captured images and videos. The mounting bracket 6 used to mount the molten pool camera in the molten pool camera device 5 has a certain degree of adjustability to meet the needs of different shooting angles of the molten pool camera.

[0095] At work,

[0096] Adjust the position of the molten pool camera equipment, and the framing area captured by the molten pool camera is as follows: Figure 2 As shown, multiple laser beams 8 surround the wire 9 and maintain the same angle with the wire, and the cladding layer 10 is located on the substrate 11;

[0097] The information receiving module acquires image data captured by the molten pool camera and transmits it to the information processing module;

[0098] Turn on the auxiliary wire feeding control system and input the relevant standard parameters through the information input module;

[0099] The real-time monitoring module is activated, and the display shows the real-time molten pool image. Then, the information processing module analyzes and calculates the molten pool image using pixel image analysis, and combines it with standard parameters to derive the actual parameters. The standard parameters and actual parameters are also displayed on the display.

[0100] Enable the background security protection module and select either "conservative control mode" or "normal control mode". When the requirements for the cladding surface morphology and quality are not high, select "normal control mode"; otherwise, select "conservative control mode". The auxiliary wire feeding control system will then make corresponding adjustment strategies according to the situation and transmit the control commands to the electrical control cabinet of the coaxial laser wire cladding equipment.

[0101] Once the adaptive wire feeding control module is activated, the auxiliary wire feeding control system will make corresponding adjustment strategies based on the situation, and the control commands will be transmitted to the electrical control cabinet of the coaxial laser wire cladding equipment.

[0102] After the coaxial laser filament cladding equipment adjusts according to the corresponding control commands, the molten pool camera captures images and videos in real time and feeds them back to the auxiliary wire feeding control system, thereby completing the entire auxiliary wire feeding control closed loop.

[0103] The real-time monitoring module in this invention displays real-time images of the molten wire pool and supports image and video saving; it can also display relevant parameters. The background safety protection module identifies unexpected situations during wire feeding, including: abnormal wire feeding; the bottom of the wire detaching from the cladding surface and forming a ball; excessive wire oscillation during the molting process; and failure to molten wire. It performs corresponding control and adjustment based on the specific unexpected situation. The adaptive wire feeding control function adjusts the wire's dry elongation before molting and provides a strategy for adjusting the wire feeding speed during molting.

[0104] Example 2:

[0105] Based on the above embodiment one, the present invention discloses an auxiliary wire feeding control method for a coaxial laser filament cladding device, comprising the following steps:

[0106] Step 1) Obtain the standard parameters of the cladding equipment during cladding operations;

[0107] After turning on the auxiliary wire feeding control system, select either "conservative control mode" or "normal control mode".

[0108] Standard parameters are input into the information processing module via the information input module. These standard parameters include the actual diameter D of wire 9. r Standard width of cladding channel W r0 Theoretical wire feeding speed V f0 Standard dry elongation length L of wire before melting r10 The standard length L of unmelted wire during the melting process. r20 , wire feed speed safety fluctuation coefficient F v 1. Safe fluctuation range of wire elongation L s Parameter L for adjusting the dry elongation of the filament a ;

[0109] Where L r10 The standard distance between the bottom end of the wire and the bottom end of the guide nozzle 7 when the wire is not fused; L r20 The standard distance between the bottom of the unmelted portion of the wire and the bottom of the wire guide nozzle during wire melting; L s L represents the tolerable deviation value when the dry elongation is safe and controllable. a To allow for a stable adjustment of the dry elongation, the allowable deviation value is determined.

[0110] Step 2) Obtain image information of the molten pool during the cladding operation;

[0111] The information receiving module receives the image information of the molten pool collected by the molten pool camera during the molten pool operation, and transmits the molten pool image information to the information processing module.

[0112] Step 3) Analyze the molten pool image information and standard parameters to obtain the actual parameters during the cladding operation, and display the molten pool image information, standard parameters and actual parameters in real time to realize the real-time monitoring function.

[0113] Step 3 specifically includes the following steps:

[0114] 3-1) Pixelate the image information in the molten pool, and divide the pixel analysis area 14 of the wire part, the pixel analysis area 15 of the molten pool part, and the pixel analysis area 16 of the cladding layer part in the pixelated image interface, as follows: Figure 3 As shown;

[0115] 3-2) Obtain the brightness feature parameters of each pixel analysis region to get the number n of bright regions in the molten pool region. p ;

[0116] 3-3) Obtain the image parameters of each pixel's analysis region, and combine them with... Figure 5 As shown, the image parameters include the wire image diameter D.i Wire image without molten wire, dry elongation length L i1 The length L of the unmelted wire during the melting process. i2 and the reference area A of the molten pool image i ; among which, L i1 It is the distance between the bottom of the wire and the bottom of the guide nozzle on the image when the wire is not fused; L i2 It is the distance between the bottom of the unmelted part of the wire and the bottom of the guide nozzle on the image during the wire melting process;

[0117] 3-4) Based on the diameter D of the wire image i and the actual diameter D of the wire r Calculate the proportionality coefficient

[0118] 3-5) Calculated based on the scaling factor P and image parameters:

[0119] Actual dry elongation of the wire before melting L r1 It is the distance between the bottom end of the wire and the bottom end of the guide nozzle when the wire is not fused.

[0120] Elongation of unmelted wire during melting L r2 It refers to the distance between the bottom of the unmelted portion of the wire visible during the melting process and the bottom of the wire guide nozzle;

[0121] Actual reference area of ​​molten pool and the actual steady-state reference area A of the molten pool r0 Actual average wire feeding speed V fr .

[0122] 3-6) Real-time display of molten pool image information, standard parameters, and actual parameters;

[0123] like Figure 1 As shown in the figure, the display screen 1 displays the molten pool image information in real time, the input standard parameters are displayed on the upper side, and the real-time actual parameters are displayed on the lower side.

[0124] On the side of the image and video display area, the upper side displays the input parameters, and the lower side displays some real-time output parameters of the molten pool and fuse.

[0125] The relevant input parameters include: the actual diameter D of the wire. r Standard width of cladding channel W r0 Theoretical wire feeding speed V f0 Standard dry elongation of the wire when it is not fused (standard distance between the bottom end of the wire and the bottom end of the guide nozzle when it is not fused) L r10 Standard length of unmelted wire during wire melting (standard distance between the bottom of the unmelted portion of the wire and the bottom of the wire guide nozzle) L r20, wire feed speed safety fluctuation coefficient F v 1. Safe fluctuation range of wire elongation (i.e., the acceptable deviation value when the elongation is safe and controllable) L s 1. Wire elongation adjustment range parameter (i.e., the tolerance value of stable elongation adjustment) L a .

[0126] The relevant output parameters include: the proportional coefficient P, and the actual dry elongation of the wire when it is not fused (the actual distance between the bottom of the wire and the bottom of the guide nozzle when it is not fused) L. r1 1. Actual length of unmelted wire during wire melting (actual distance between the bottom of the unmelted portion of the wire and the bottom of the wire guide nozzle) L r2 The distance L between the bottom of the guide wire tip and the cladding surface dr Number of highlighted areas in the molten pool, n p Actual reference area A of the molten pool r Actual steady-state reference area A of the molten pool r0 Actual average wire feeding speed V fr .

[0127] When there is no significant fluctuation in the filament material, a localized area can be observed on the filament surface using a molten pool camera. This area has a pigment brightness different from the filament material itself and is relatively stationary relative to the filament surface. Therefore, it can be identified as a special point and used as the actual average filament feeding speed V. fr Reference basis; accordingly, the actual average wire feeding speed V fr The method for obtaining it is as follows:

[0128] During the stable cladding process, based on the molten pool image information, specific points in the wire are captured, and the distance of these points from the bottom of the wire guide nozzle is recorded. Time T p1 and Time T p2 According to the formula Calculate the actual average wire feeding speed V fr ,like Figure 8 As shown.

[0129] Actual steady-state reference area A of the molten pool r0 The method for obtaining it is as follows:

[0130] During the stabilization cladding process, an equation is used based on the molten pool image information.

[0131] Where T w2 and T w1 To stabilize the time at time node 2 and time node 1 selected during the cladding process, A ri This represents the actual real-time reference area of ​​the molten pool corresponding to this range.

[0132] Actual average wire feeding speed V fr It can intuitively reflect the actual wire feeding situation and can be compared with the theoretical wire feeding speed V. f0 For comparison; actual reference area A of the molten pool r It can reflect the size of the molten pool and is related to the actual steady-state reference area A of the molten pool. r0 By comparing the two methods, the real-time stability of the fuse process can be qualitatively assessed, achieving good monitoring results.

[0133] Step 4) Compare the actual parameters and standard parameters within the predetermined deviation range, identify abnormal situations in the wire feeding process of the cladding equipment, generate and send corresponding control commands to the cladding equipment, and realize the background safety protection function.

[0134] Abnormal situations include:

[0135] Abnormal wire feeding, specifically including the actual average wire feeding speed V fr and theoretical wire feeding speed V f0 The difference is too large, or the wire feeder is stuck and not feeding wire;

[0136] Abnormalities in the cladding channel, such as the bottom end of the wire detaching from the surface of the cladding channel and forming a ball, will result in discontinuities on the cladding surface.

[0137] If the wire oscillation amplitude exceeds the predetermined value during the cladding process, it will lead to unstable cladding.

[0138] An unfused wire is usually caused by insufficient laser power or interruption of light output.

[0139] Step 4, which involves identifying wire feeding abnormalities and generating control commands, includes the following steps:

[0140] 4-11) Obtain standard and actual parameters, including the safe fluctuation range L of dry elongation. s and the safety fluctuation coefficient F of the wire feeding speed v ;

[0141] 4-12) Standard length L of unmelted wire when calibrating the fuse r20 ;

[0142] Under normal laser cladding conditions Where T w2 and T w1 For normal fuse operation, select the times at time node 2 and time node 1, L r2i This represents the actual elongation of the unmelted wire during the melting point between time nodes 2 and 1.

[0143] 4-13) When L r2 >L r20 +L s or L r2 <Lr20 -L s When the system detects an abnormality in the dry elongation of the filament, it displays the abnormality and sends a control command to the electrical control cabinet of the coaxial laser filament cladding equipment to "stop movement, light emission and filament feeding".

[0144] 4-14) When V fr >(1+F v V f0 or V fr <(1-F v V f0 When the system detects an abnormality in the "wire feeding speed", it displays the abnormal situation and sends a control command to the electrical control cabinet of the coaxial laser filament cladding equipment to "stop movement, light output and wire feeding".

[0145] Step 4, the steps of identifying and forming control commands for the bottom end of the wire detaching from the cladding surface and forming a ball, include:

[0146] 4-21) Before starting laser cladding work, select normal control mode or conservative control mode; when the requirements for cladding surface morphology and quality are not high, select normal control mode; otherwise, select conservative control mode.

[0147] 4-22) Obtain standard parameters and actual parameters, including the number of highlighted areas n. p ;

[0148] 4-23) When n P When the value is 2, it indicates that two bright pixel areas appear in the molten pool pixel area, including droplet 13 and molten pool 12, as shown. Figure 6 As shown in the figure, droplet 13 at the bottom of the wire is not connected to the cladding layer. This is considered an "abnormal state of the cladding channel" and the system enters the control mode. When L... r2 <L r20 -L s This indicates a potential for the bottom of the wire to detach from the surface of the cladding channel and form a ball, which is also identified as an "abnormal state of the cladding channel" and enters the control mode.

[0149] 4-24) When an "abnormal state of the cladding channel" occurs;

[0150] If the conservative control mode is selected in step 4-21, an abnormal situation will be displayed, and a control command of "stop moving, emitting light and feeding wire" will be sent to the electrical control cabinet of the coaxial laser filament cladding equipment.

[0151] If the normal control mode is selected in step 4-21, the abnormal situation is recorded, and a "rapid wire feeding" control command is sent to the electrical control cabinet of the coaxial laser filament cladding equipment to increase the wire feeding speed V of the cladding equipment. f Adjusted to V f =1.5V f0Then, when n P =1 and L r2 >L r20 -L s Then, a "normal wire feeding" control command is sent to the cladding equipment, which increases the wire feeding speed V of the cladding equipment. f Adjusted to V f =V f0 .

[0152] Step 4, the steps of identifying and generating control commands when the wire oscillation amplitude exceeds a predetermined value during the wire melting process, include:

[0153] 4-31) Select either the normal control mode or the conservative control mode; when the surface morphology and quality requirements of the cladding are not high, select the normal control mode; otherwise, select the conservative control mode.

[0154] 4-32) Obtain standard parameters and actual parameters, including the standard width W of the cladding channel. r0 Standard dry elongation L of the filament before melting r10 ;

[0155] 4-33) Calculate the safe swing angle θ s ;

[0156] According to θ s In the pixelated image interface, define the safe swing area 21, and then determine the wire diameter D. r Define stable regions, such as Figure 7 As shown;

[0157] 4-34) When all pixels of the wire material feature are in the stable region, it is determined as "no swaying";

[0158] When some pixels of the wire material feature are within the safe swing area, and no pixels are outside the stable area and the safe swing area, it is judged as "normal swing".

[0159] When some pixels of the wire material feature are outside the stable region and the safe swing region, it is judged as "abnormal swing".

[0160] 4-35) When "abnormal oscillation" occurs;

[0161] If the conservative control mode is selected in step 4-31, the electrical control cabinet of the coaxial laser filament cladding equipment will send a control command to "stop movement, light emission and wire feeding".

[0162] If the normal control mode is selected in step 4-31, a "decelerate wire feeding" control command is sent to the electrical control cabinet of the coaxial laser filament cladding equipment, thereby reducing the wire feeding speed V of the cladding equipment. f Adjusted to V f =0.9Vf0 Then, when the pixels of the wire feature are in the "no wobbling" state, a "normal wire feeding" control command is sent to the cladding equipment, increasing the wire feeding speed V. f Adjusted to V f =V f0 .

[0163] Step 4, which involves identifying unfused fuses and generating control commands, includes the following steps:

[0164] When there is no fuse, no molten pool will be generated. Therefore, when the highlighted pixel area in the pixel analysis region of the molten pool is 0, i.e., n... P =0, the system displays an abnormal situation and sends a control command to the electrical control cabinet of the coaxial laser filament cladding equipment to "stop movement, light output and wire feeding".

[0165] Step 5) Compare the actual parameters with the standard parameters within the predetermined deviation range, generate and send control commands to the cladding equipment to adjust the wire dry elongation before cladding and the wire feeding speed during cladding, so as to realize the adaptive wire feeding control function.

[0166] The adaptive wire feeding control function includes pre-adjustment of wire dry elongation before melting and adjustment of wire feeding speed during the melting process;

[0167] Pre-adjustment of wire dry elongation before cladding refers to determining the height of the cladding surface from the bottom of the wire guide before the laser cladding head reaches the designated welding or additive manufacturing area and before the cladding work begins, and adopting different wire dry elongation adjustment strategies according to different situations.

[0168] The wire feed speed adjustment during the wire melting process refers to adjusting the feed speed based on the actual length L of the unmelted wire during the cladding operation of the laser cladding head. i2 It determines the fuse state and takes adjustment strategies when the fuse is in a metastable state.

[0169] In step 5, the actual parameters and standard parameters are compared within a predetermined deviation range, and a control command is generated and sent to the cladding equipment to adjust the wire dry elongation before cladding. This includes the following steps:

[0170] For different cladding processes, especially additive manufacturing, a height difference often exists between the actual and theoretical cladding surfaces at higher elevations due to thermal expansion and contraction. Therefore, during intermittent cladding intervals, it is necessary to obtain the image distance L between the bottom of the guide nozzle and the cladding surface. di Therefore, a suitable strategy for adjusting the dry elongation of the filament before cladding can be selected, such as... Figure 4 As shown;

[0171] 5-11) Obtain standard and actual parameters, including the standard dry elongation length L of the filament. r10 The parameter L for adjusting the dry elongation of the filament a;

[0172] 5-12) Obtain the image distance L from the bottom of the guide wire nozzle to the cladding surface from the image parameters of each pixel analysis region. di The actual distance from the bottom of the guide wire nozzle to the cladding surface is obtained by calculation. And display L in the system dr ;

[0173] 5-13) When L dr >L r10 +L a or L dr <L r10 -L a If the actual distance between the bottom of the guide wire nozzle and the cladding surface is outside the stable adjustment range, the system will display an abnormality and send a "start path coordinate value offset" control command to the electrical control cabinet of the coaxial laser cladding equipment. The cladding equipment will then move the laser cladding head, causing L... dr =L r10 Then, a control command to "stop path coordinate value offset" is sent to the electrical control cabinet of the coaxial laser cladding equipment.

[0174] 5-14) When L r10 -L a <L dr <L r10 +L a When the actual distance between the bottom of the guide tip and the cladding surface is within the stable adjustment range, the system displays an abnormal situation and activates the dry extension pre-adjustment function.

[0175] At this time, if L dr >L r10 Then, a "normal wire feeding" control command is sent to the electrical control cabinet of the coaxial laser filament cladding equipment, with a wire feeding speed V. f0 Continue feeding the wire until L r1 =L dr Then, a "stop wire feeding" control command is sent to the electrical control cabinet of the coaxial laser filament cladding equipment.

[0176] If L dr <L r10 Then, a "normal wire drawing" control command is sent to the electrical control cabinet of the coaxial laser filament cladding equipment, with a wire drawing speed V. f0 Continue drawing the fibers until L is reached. r1 =L dr Then, a "stop drawing" control command is sent to the electrical control cabinet of the coaxial laser filament cladding equipment.

[0177] In step 5, the actual parameters and standard parameters are compared within a predetermined deviation range, and a control command is generated and sent to the cladding equipment to adjust the wire feeding speed when adjusting the cladding wire. This includes the following steps:

[0178] 5-21) Obtain standard and actual parameters, including the filament dry elongation length adjustment range parameter L. a The standard length L of unmelted wire during the melting process. r20 Function and actual elongation length L of unmelted wire during melting r2 ;

[0179] 5-22) When L r2 >L r20 +L a This indicates that the elongation of the unmelted wire during the cladding process exceeds the standard value. At this point, a "speed up wire feeding" control command is sent to the electrical control cabinet of the coaxial laser cladding equipment, increasing the wire feeding speed V of the cladding equipment. f Adjusted to V f =1.2V f0 until L r2 =L r20 Then, a "normal wire feeding" control command is sent to the electrical control cabinet of the coaxial laser filament cladding equipment; the wire feeding speed V is set to... f Adjusted to V f =V f0 ;

[0180] 5-23) When L r2 <L r20 -L a This indicates that the elongation of the unmelted wire during the cladding process is less than the standard value. At this point, a "decelerate wire feeding" command is sent to the control cabinet of the coaxial laser cladding equipment, adjusting the wire feeding speed V of the cladding equipment. f Adjusted to V f =0.9V f0 until L r2 =L r20 Then, a "normal wire feeding" control command is sent to the electrical control cabinet of the coaxial laser filament cladding equipment; the wire feeding speed V is set to... f Adjusted to V f =V f0 .

[0181] This invention discloses an auxiliary wire feeding control system and method for a coaxial laser filament cladding equipment. This system works in conjunction with the coaxial laser filament cladding equipment and the molten pool camera. Based on molten pool image acquisition technology, it obtains images and videos of the coaxial laser filament cladding process. Pixel image analysis is used to obtain real-time filament and molten pool conditions during the cladding process. The system selects appropriate solutions based on judgment criteria and bases within the auxiliary wire feeding control system, and controls the filament material of the coaxial laser filament cladding equipment through control commands. This achieves real-time monitoring of the cladding process, background safety protection, and adaptive wire feeding control.

[0182] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. An auxiliary wire feeding control method for a coaxial laser filament cladding device, characterized in that, Includes the following steps: 1) Obtain the standard parameters of the cladding equipment during cladding operations; 2) Obtain image information of the molten pool during cladding operations; 3) Analyze the molten pool image information and standard parameters to obtain the actual parameters during the cladding operation, and display the molten pool image information, standard parameters, and actual parameters in real time; 4) Compare the actual parameters with the standard parameters within the predetermined deviation range, identify abnormal situations in the wire feeding process of the cladding equipment, and generate and send corresponding control commands to the cladding equipment; 5) Compare the actual parameters with the standard parameters within the predetermined deviation range, generate and send control commands to the cladding equipment to adjust the wire dry elongation before cladding and the wire feeding speed during cladding; In step 1, the standard parameters include: True diameter D of the wire r Standard width of cladding channel W r0 Theoretical wire feeding speed V f0 Standard dry elongation length L of wire before melting r10 The standard length L of unmelted wire during the melting process. r20 , Safety fluctuation coefficient F of wire feeding speed v 1. Safe fluctuation range of wire elongation L s Parameter L for adjusting the dry elongation of the filament a ; In step 3, the molten pool image information and standard parameters are analyzed to obtain the actual parameters during the cladding operation, including: 3-1) Pixelate the image in the molten pool image information, and divide the pixel analysis area of ​​the wire part, the pixel analysis area of ​​the molten pool part and the pixel analysis area of ​​the cladding layer part in the pixelated image interface; 3-2) Obtain the brightness feature parameters of each pixel analysis region to get the number n of bright regions in the molten pool region. p ; 3-3) Obtain the image parameters of each pixel analysis region to get the wire image diameter D. i Wire image without molten wire, dry elongation length L i1 The length L of the unmelted wire during the melting process. i2 and the reference area A of the molten pool image i ; 3-4) Obtain the conversion ratio coefficient ; 3-5) Based on the proportionality coefficient The actual dry elongation L of the filament when it is not fused is calculated using image parameters. r1 The actual length L of the unmelted wire during the melting process. r2 Actual reference area A of the molten pool r And the actual steady-state reference area A of the molten pool r0 Actual average wire feeding speed V fr ; Abnormal situations in step 4 include abnormal wire feeding, the bottom end of the wire detaching from the surface of the cladding channel and forming a ball, the wire swing amplitude exceeding the predetermined value during the wire melting process, and failure to melt the wire. The steps for identifying the wire feeding abnormality and generating control commands include: 4-11) Obtain standard parameters and actual parameters; 4-12) Standard length L of unmelted wire when calibrating the fuse r20 ; T w2 and T w1 For normal fuse operation, select the times at time node 2 and time node 1, L r2i This represents the actual elongation of the unmelted wire during the melting point between time nodes 2 and 1. 4-13) When L r2 >L r20 +L s or L r2 <L r20 -L s At that time, it was determined that "the dry elongation of the filament is abnormal" and a control command to "stop moving, glazing and feeding the filament" was sent to the cladding equipment. 4-14) When V fr >(1+F v V f0 or V fr <(1-F v V f0 When the "wire feeding speed" is abnormal, a control command to "stop moving, light output and wire feeding" is sent to the cladding equipment.

2. The auxiliary wire feeding control method for a coaxial laser filament cladding device according to claim 1, characterized in that, The steps for identifying and forming control commands regarding the bottom end of the filament detaching from the cladding surface and forming a ball include: 4-21) Choose between normal regulation mode or conservative regulation mode; 4-22) Obtain standard parameters and actual parameters; 4-23) When n P =2, or L r2 <L r20 -L s At that time, it was determined to be an "abnormal state of the cladding channel"; 4-24) When an "abnormal state of the cladding channel" occurs; If the conservative control mode is selected in step 4-21, a control command of "stop moving, light output and wire feeding" is sent to the cladding equipment. If the normal control mode is selected in step 4-21, a "rapid wire feeding" control command is sent to the cladding equipment, which increases the wire feeding speed V of the cladding equipment. f Adjusted to V f =1.5V f0 Then, when n P =1 and L r2 >L r20 -L s Then, a "normal wire feeding" control command is sent to the cladding equipment, which increases the wire feeding speed V of the cladding equipment. f Adjusted to V f =V f0 .

3. The auxiliary wire feeding control method for a coaxial laser filament cladding device according to claim 1, characterized in that, The steps for identifying and generating control commands when the wire oscillation amplitude exceeds a predetermined value during the wire melting process include: 4-31) Choose between normal regulation mode or conservative regulation mode; 4-32) Obtain standard parameters and actual parameters; 4-33) Calculate the safe swing angle θ s ; θ s =arctan( According to θ s Define a safe swing area in the pixelated image interface, and then determine the wire diameter D. r Delineate stable zones; 4-34) When all pixels of the wire material feature are in the stable region, it is determined as "no swaying"; When some pixels of the wire material feature are within the safe swing area, and no pixels are outside the stable area and the safe swing area, it is determined to be "normal swing". When some pixels of the wire material feature are outside the stable region and the safe swing region, it is judged as "abnormal swing". 4-35) When "abnormal oscillation" occurs; If the conservative control mode is selected in step 4-31, a control command of "stop moving, light output and wire feeding" is sent to the cladding equipment. If the normal control mode is selected in step 4-31, a "decelerate wire feeding" control command is sent to the cladding equipment to reduce the wire feeding speed V of the cladding equipment. f Adjusted to V f =0.9V f0 Then, when the pixels of the wire feature are in the "no wobbling" state, a "normal wire feeding" control command is sent to the cladding equipment, increasing the wire feeding speed V. f Adjusted to V f =V f0 .

4. The auxiliary wire feeding control method for a coaxial laser filament cladding device according to claim 1, characterized in that, In step 5, comparing the actual parameters and standard parameters within a predetermined deviation range, generating and sending a control command to the cladding equipment to adjust the wire dry elongation before cladding, includes the following steps: 5-11) Obtain standard parameters and actual parameters; 5-12) Obtain the image distance L from the bottom of the guide wire nozzle to the cladding surface from the image parameters of each pixel analysis region. di The actual distance from the bottom of the guide wire nozzle to the cladding surface is obtained by calculation. ; 5-13) When L dr >L r10 +L a or L dr <L r10 -L a At that time, a control command for "start path coordinate value offset" is sent to the cladding equipment, and the cladding equipment moves the laser cladding head so that L dr =L r10 Then, a control command to "stop path coordinate value offset" is sent to the cladding equipment. 5-14) When L r10 -L a <L dr <L r10 +L a hour, If L dr >L r10 Then, a "normal wire feeding" control command is sent to the cladding equipment at a wire feeding speed V. f0 Continue feeding the wire until L r1 =L dr Then, a "stop wire feeding" control command is sent to the cladding equipment. If L dr <L r10 Then, a "normal wire drawing" control command is sent to the cladding equipment, with a wire drawing speed V. f0 Continue drawing the fibers until L is reached. r1 =L dr Then, a "stop wire drawing" control command is sent to the cladding equipment.

5. The auxiliary wire feeding control method for a coaxial laser filament cladding device according to claim 1, characterized in that, In step 5, comparing the actual parameters and standard parameters within a predetermined deviation range, generating and sending a control command to the cladding equipment to adjust the wire feeding speed during the cladding process, includes the following steps: 5-21) Obtain standard parameters and actual parameters; 5-22) When L r2 >L r20 +L a Send a "speed up wire feeding" control command to the cladding equipment to increase the wire feeding speed V of the cladding equipment. f Adjusted to V f =1.2V f0 until L r2 =L r20 Then, send a "normal wire feeding" control command to the cladding equipment; adjust the wire feeding speed V. f Adjusted to V f =V f0 ; 5-23) When L r2 <L r20 -L a Send a "decelerate wire feeding" command to the cladding equipment to reduce the wire feeding speed V of the cladding equipment. f Adjusted to V f =0.9V f0 until L r2 =L r20 Then, send a "normal wire feeding" control command to the cladding equipment; adjust the wire feeding speed V. f Adjusted to V f =V f0 .

6. An auxiliary wire feeding control system for a coaxial laser filament cladding device, used to implement the auxiliary wire feeding control method according to any one of claims 1 to 5, characterized in that, include: The information input module is used to input the standard parameters of the cladding equipment during cladding operations; The information receiving module is used to receive image information of the molten pool during cladding operations. The information processing module calculates the actual parameters during the cladding operation based on the molten pool image information and standard parameters, compares the actual parameters with the standard parameters within a predetermined deviation range, and generates control commands for controlling the cladding equipment. The information sending module is used to send the control commands to the cladding equipment.

7. The auxiliary wire feeding control system for a coaxial laser cladding device according to claim 6, characterized in that, The information processing module includes: The real-time monitoring module is used to display the standard parameters, molten pool image information, and actual parameters; The background safety protection module is used to compare actual parameters and standard parameters within a predetermined deviation range to identify abnormal situations during the wire feeding process of the cladding equipment and generate corresponding control commands. The adaptive wire feeding control module is used to compare actual parameters with standard parameters within a predetermined deviation range, thereby generating control commands to adjust the wire dry elongation before melting and the wire feeding speed during melting.

8. The auxiliary wire feeding control system of a coaxial laser filament cladding device according to claim 6, characterized in that: The cladding equipment is a coaxial laser wire cladding equipment, which has walking, laser control and wire feeding control functions; The molten pool image information is acquired by the molten pool camera device and transmitted to the information receiving module; The information processing module segments the molten pool image information into pixel analysis regions for the wire part, the molten pool part, and the cladding layer part, and uses pixel image analysis to identify and analyze each pixel analysis region.

Images