Silver-based alloy material automatic welding equipment based on visual detection and operation method

Abstract

The application discloses a silver-based alloy material automatic welding equipment based on visual detection and a running method thereof. The welding equipment comprises a PLC controller, a copper strip positioning device, a welding mechanism, a silver point shearing force detection mechanism, a size appearance online detection mechanism, a shearing device and a copper strip feeding device which are electrically connected with the PLC controller. The application utilizes a CCD image processor to realize online detection and processing of low-voltage alloy contact material welding products. If defective products are detected, the defective products are marked as substandard products (NG marking), and the substandard products are directly sheared and separated in a subsequent defective product shearing station, so that edge materials or waste materials are avoided from being mixed into normal good products. The welding technology and the visual detection technology are integrated, work efficiency is improved, human subjective error factors are reduced, and higher automation level is achieved.

Description

Technical Field

[0001] This invention belongs to the field of low-voltage electrical materials processing technology, specifically relating to an automatic welding equipment and operating method for silver-based alloy materials based on vision inspection. Background Technology

[0002] Currently, traditional medium-frequency DC inverter welding machines on the market are relatively simple in their mechanism and principle. Their main components include a workbench and a medium-frequency inverter power supply. The electrical control system often consists of only simple foot switches, AC contactors, small intermediate relays, power switches, limit switches, and operation buttons. This electrical control system can meet general manual operation requirements. For operators, under normal equipment operation, it is necessary to monitor the quality of the silver-based modules in real time, regularly inspecting their dimensions, silver spot overflow, silver spot location, and surface defects, which consumes a significant amount of time and effort. Furthermore, manual operation is extremely inefficient, and errors can increase the defect rate, reducing product profitability. The shortcomings of traditional medium-frequency DC inverter welding machines, such as slow speed, low efficiency, and the inability to automatically detect product appearance and dimensions, count and control shutdown, and separate defective products, severely restrict the development of silver-based module production technology and fail to improve enterprise production efficiency and reduce labor costs. Therefore, research on how to reduce human intervention, improve the operating efficiency of automated welding machines for silver-based modules, and address issues such as online detection and separation of defective products and automatic shutdown in case of malfunction has become a focus of attention in this field.

[0003] Chinese invention patent application CN 116100211 A discloses an automated welding system and method, including a PLC, a central processing unit (CPU), a power module, a vision module, and an execution system. The execution system includes a robotic arm and a welding system. The welding system is mounted on the robotic arm. The PLC is connected to the CPU, and the CPU communicates with the PLC, power module, vision module, and execution system. The vision module collects weld data from the workpiece to be welded and transmits it to the PLC. The PLC analyzes the collected data and matches it with a database. The PLC sends a start signal to the CPU, which then guides the welding operation of the execution system through the vision module. This invention utilizes the cooperation of the vision module and the execution system to provide more accurate data, expanding the application scenarios of the welding system. Combined with the PLC and CPU, it can inspect the welded workpiece to determine if the weld is completely welded, resulting in high automation, high welding precision, and high efficiency. However, the aforementioned solution only detects whether the weld is completely welded; it cannot assess the quality of the weld or handle welding defects. Summary of the Invention

[0004] This invention provides an automatic welding equipment and operating method for silver-based alloy materials based on vision inspection. By utilizing the logic control function of a PLC and combining a CCD image processor and a shearing device, it solves the defects of traditional medium-frequency DC inverter power supply welding systems that cannot automatically detect product appearance and size, or separate defective products.

[0005] To solve the above problems, the present invention is achieved through the following technical solution:

[0006] An automatic welding equipment for silver-based alloy materials based on vision detection includes a PLC controller and a copper strip positioning device arranged sequentially from the feeding tray to the receiving tray. The device is used to receive signals from the PLC control and to position and fix the copper strip.

[0007] The welding mechanism includes a silver strip feeding device and an upper and lower electrode welding device. The silver strip feeding device is used to receive signals controlled by the PLC and provide the function of feeding silver strip. The upper and lower electrode welding device is used to receive signals controlled by the PLC and work together with the silver strip feeding device to perform point contact discharge welding of silver.

[0008] The silver spot shear force detection mechanism is used to apply a certain pressure to the workpiece to detect whether the silver spot is poorly soldered, and then feeds back to the PLC controller.

[0009] The online size and appearance inspection mechanism is used to acquire images of workpieces, analyze and process the size information of the images, and transmit the processing result signal to the PLC controller.

[0010] The shearing device receives signals from the PLC controller and is responsible for cutting off defective workpieces;

[0011] The copper strip feeding device receives signals from the PLC controller and is responsible for feeding the copper strip.

[0012] As the preferred solution of the above scheme

[0013] The copper strip positioning device includes two U-shaped detection sensors, a positioning pin, a positioning cylinder, and a mechanical fixing mechanism. The positioning cylinder is mounted on the mechanical fixing mechanism, the positioning pin is connected to the output of the positioning cylinder and is located below the copper strip, and the U-shaped detection sensors are mounted on the positioning cylinder to detect the position of the cylinder's movement.

[0014] Preferably, the silver belt feeding device includes a servo controller and a servo motor, a transmission coupling, and a cam feeder. The output shafts of the servo controller and the servo motor are connected to the cam feeder via the transmission coupling, and the cam feeder is connected to the silver belt.

[0015] Preferably, the power supply system of the upper and lower electrode welding device mainly consists of a medium-frequency inverter controller and a transformer. The medium-frequency inverter controller includes a three-phase power input module, an IGBT module, a power drive module, a main control board, and a programmer. The transformer includes a secondary current transformer, a temperature sensor, and a transformer coil. The AC 380V power input to the three-phase power input module is converted to DC power input to the IGBT module. The IGBT module is driven by the power drive module controlled by the main control board. The two outputs of the IGBT module are connected to the input terminals of the transformer coil via current transformers, and the output terminals of the transformer coil are connected to the upper and lower electrodes via secondary current transformers. The two outputs of the IGBT module are also connected to the main control board via current transformers. The temperature sensor detects the transformer and inputs it to the main control board. The welding secondary current detected by the secondary current transformer is input to the main control board. The main control board also communicates with the programmer and the PLC controller.

[0016] Preferably, the silver point shear force detection mechanism includes a cylinder and a pressure sensor, both connected to a PLC controller, with the cylinder output connected to the pressure sensor.

[0017] Preferably, the online size and appearance inspection mechanism includes a CCD image processor, a bracket, a display, and a camera. The camera, display, and CCD image processor are mounted on the bracket. The camera is connected to the CCD image processor and is located above the workpiece. The CCD image processor is connected to the PLC controller and the display, respectively.

[0018] Preferably, the copper strip feeding device includes a servo controller and a servo motor, and a feeding roller. The output ends of the servo controller and the servo motor are connected to the feeding roller, and the feeding roller clamps the copper strip to realize the rolling feeding of the copper strip.

[0019] This invention also discloses an operation method for an automatic welding device for silver-based alloy materials based on vision inspection, comprising the following steps:

[0020] (1) Position the copper strip, and then transport the silver spot to be welded to the welding station for electrical discharge welding;

[0021] (2) After the welding action is completed, the copper strip moves down one station and enters the silver point shear force detection station. Each time, a certain pressure is applied to check whether the silver point is poorly welded. If there is a poor weld, it is marked as NG.

[0022] (3) After the shear force test is completed, the copper strip is moved to the appearance and size inspection station. The relevant defects are identified by CCD image detection. If there are defects, they are marked as NG.

[0023] (4) After completing the online image detection, the product enters the shearing station. If the station in step (2) and / or step (3) detects that the product is marked NG, the workpiece marked NG is cut off at the station to prevent defective products from entering the good products. The welding and quality inspection of the workpiece are completed. Each movement of the copper strip is controlled by the copper strip feeding device.

[0024] As a preferred option of the above scheme,

[0025] The implementation process of step (3) includes the following steps:

[0026] (31) CCD settings: Set the pixel count and sampling frequency respectively;

[0027] (32) Register images: Manually trigger the taking of pictures of normal and intact samples, save the collected template images, and provide rapid matching for subsequent detection;

[0028] (33) Window settings: Take three feature points in the X-axis direction for window recognition settings, namely X1, X2 and X3; all three windows use the image detection tool at the edge position, and the filter algorithm of X1 is contrast conversion and binarization;

[0029] The current X-axis pixel value is obtained after filtering; the filter algorithm for X2 is contrast conversion and averaging.

[0030] The current X-axis pixel value is obtained after filtering; the filter algorithm for X3 is contrast conversion and shrinkage.

[0031] After processing with a filter, the current X-axis pixel value is obtained as X3. The pixel value of the silver point in the X-axis direction is calculated as follows: ΔX = X3 - X2.

[0032] (34) Position correction: When the workpiece image shifts, a reference correction is performed; with X1 as the reference position, X2 and X3 take X1 as the correction reference. After the sampled image shifts, it is corrected according to the X1 position so that the relative positions between X2 and X3 are kept on the same X-axis.

[0033] (35) Calculation: After obtaining the values ​​of X1, X2 and X3 from step (33), the pixel value of the silver point in the X-axis direction on the workpiece needs to be calculated. The calculation formula is: ΔX = X3 - X2. At this time, the upper and lower tolerance limits of ΔX need to be set.

[0034] (36) Output setting: Select ΔX output. When the actual size exceeds the ΔX tolerance range, the image processor hardware output port will transmit the NG signal to the PLC for subsequent processing.

[0035] (37) Continuous detection: After completing the first 6 steps of settings, the image processor has completed the relevant size detection settings and can run the detection continuously; when the copper strip runs to the size and appearance online detection station during the welding process, the PLC controller triggers the CCD camera to take pictures through the transistor output port, collects the original image of the current workpiece, and then performs template matching, position correction, calculation, and output settings in the window settings.

[0036] Preferably, in step (4), the operation method of the servo motor encoder in the copper strip feeding device is as follows: during the copper strip feeding process, the servo motor encoder corresponding angle starts from 0° and ends at 60°; during the copper strip positioning process, the servo motor encoder corresponding angle starts from 61° and ends at 85°; then, the silver point feeding and silver point feeding position detection is performed, and the servo motor encoder corresponding angle starts from 86° and ends at 160°; next, the silver point welding is performed, and the servo motor encoder corresponding angle starts from 161° and ends at 200°; then, the shearing force detection is performed, and the servo motor encoder corresponding angle starts from 201° and ends at 240°; then, the CCD image detection is performed, and the servo motor encoder corresponding angle starts from 241° and ends at 300°; finally, the top dead point detection is performed, and the servo motor encoder corresponding angle starts from 301° and ends at 360°.

[0037] Compared with the prior art, the present invention has the following advantages:

[0038] 1. This invention utilizes a CCD image processor to achieve online inspection and processing of low-voltage alloy contact material welding products. If a defective product is detected, it is marked as an NG product and directly sheared and separated in the subsequent defective product shearing station, avoiding the mixing of edge material or waste material with normal good products. It integrates welding technology and visual inspection technology, which not only improves work efficiency and reduces human subjective error factors, but also has a higher level of automation.

[0039] 2. This invention utilizes a silver point shear force detection mechanism to determine the shear force of the silver point by adjusting the air pressure. If the welding is not firm or the welding shear force does not meet the requirements, the silver point will be pushed off without any shear force feedback value. The system determines that it is a defective product and will directly shear it in the shearing station, further reducing the product defect rate.

[0040] 3. The copper strip feeding device controls the copper strip transportation, enabling precise and efficient control of the equipment's operating rhythm, completing the fully automatic welding process, ensuring the stability of the equipment and the precise control of the welding process, and resulting in a higher yield of welded workpieces. Attached Figure Description

[0041] Figure 1 This is a schematic diagram illustrating the working principle of the present invention;

[0042] Figure 2This is a schematic diagram of the working principle of this power supply system;

[0043] Figure 3 A schematic diagram of the interface for registering images;

[0044] Figure 4 This is a schematic diagram before X1 filtering.

[0045] Figure 5 This is a schematic diagram after X1 filtering;

[0046] Figure 6 This is a schematic diagram before X2 filtering.

[0047] Figure 7 This is a schematic diagram after X2 filtering;

[0048] Figure 8 This is a schematic diagram before X3 filtering;

[0049] Figure 9 This is a schematic diagram after X3 filtering. Detailed Implementation

[0050] To make the objectives and advantages of the present invention clearer, the present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0051] like Figure 1 As shown, this invention discloses an automatic welding equipment for silver-based alloy materials based on vision inspection, including a PLC controller, and a copper strip positioning device, a welding mechanism, a silver spot shear force detection mechanism, an online dimensional appearance inspection mechanism, a shearing device, and a copper strip feeding device electrically connected to the PLC controller. The copper strip positioning device, welding mechanism, silver spot shear force detection mechanism, online dimensional appearance inspection mechanism, shearing device, and copper strip feeding device correspond to the copper strip positioning station, welding station, shear force detection station, online dimensional appearance inspection station, shearing station, and copper strip feeding station, respectively.

[0052] The welding mechanism includes a silver strip feeding device and upper and lower electrode welding devices. The copper strip positioning device, silver strip feeding device, upper and lower electrode welding devices, silver spot shear force detection mechanism, online dimensional and appearance inspection mechanism, shearing device, and copper strip feeding device are arranged sequentially from the feeding tray to the receiving tray.

[0053] The copper strip positioning device receives signals from the PLC control system and positions and fixes the copper strip. The device includes two U-shaped detection sensors, a positioning pin, a positioning cylinder, a linear guide rail, and a mechanical fixing mechanism. The positioning cylinder is mounted on the mechanical fixing mechanism. The positioning pin is connected to the output of the positioning cylinder and located below the copper strip. The U-shaped detection sensors are mounted on the positioning connection plate. The U-shaped detection sensors accurately detect the positioning cylinder's position, and the positioning pin precisely locks the copper strip to ensure it does not shift during welding. The mechanical fixing mechanism fixes the positioning cylinder, which drives the positioning pin to position the copper strip.

[0054] The silver belt feeding device receives signals from the PLC control system and performs the silver belt feeding function. It includes a servo controller and servo motor, a transmission coupling, and a cam feeder. The output shafts of the servo controller and servo motor are connected to the cam feeder via the transmission coupling, and the cam feeder is connected to the silver belt. The servo motor and servo controller primarily provide power for the silver belt feeding; the transmission coupling connects the servo motor and the cam feeder; the cam feeder's function is to provide the silver belt feeding function through the rotation of the servo motor.

[0055] The upper and lower electrode welding device is used in conjunction with a cam feeder and includes an upper electrode, a lower electrode, and a welding transformer connecting block. The upper electrode is a moving module driven by the cam feeder according to the silver spot feeding position, its function being to contact the silver spot for discharge welding. The lower electrode is a fixed module, its function being to support the lower surface of the copper strip and simultaneously form a welding circuit. The welding transformer connecting block's function is to provide a discharge cable for the welding power source. Figure 2 As shown, the power system of the upper and lower electrode welding device mainly consists of a medium-frequency inverter controller and a transformer. The medium-frequency inverter controller includes a three-phase power input module, an IGBT module, a power drive module, a main control board, and a programmer.

[0056] The power system of the upper and lower electrode welding device mainly consists of a medium-frequency inverter controller and a transformer. The medium-frequency inverter controller includes a three-phase power input module, an IGBT module, a power drive module, a main control board, and a programmer. The transformer includes a secondary current transformer, a temperature sensor, and a transformer coil. A 380V AC power input to the three-phase power input module is converted to DC power input to the IGBT module. The IGBT module is driven by the power drive module controlled by the main control board. The two outputs of the IGBT module are connected to the input terminals of the transformer coil via current transformers, and the output terminals of the transformer coil are connected to the upper and lower electrodes via secondary current transformers. The two outputs of the IGBT module are also connected to the main control board via current transformers. The temperature sensor detects the transformer current and inputs it to the main control board. The welding secondary current detected by the secondary current transformer is input to the main control board. The main control board also communicates with the programmer and the PLC controller. Welding parameters are entered by the programmer or the PLC touchscreen. The main control board provides an RS485 communication interface for communication between the welding power supply and the PLC. The power drive module is responsible for driving the IGBT module. The secondary current transformer on the transformer is responsible for feeding back the welding secondary current to the main control board, and the temperature sensor is used to protect the welding power supply from overheating. Meanwhile, this power supply system operates at a frequency of 1kHz and has a maximum output current of 18kA. It is mainly used for welding contacts and wires of various low-voltage components. In the current mainstream silver-based material welding, the medium-frequency inverter resistance welding machine is one of the technological requirements for achieving high current and short time. Due to the limited lifespan of the welding electrode material, the equipment is designed with a counting stop function. The welding power supply counts and provides feedback; when the set value for electrode re-grinding is reached, the PLC controls the equipment to stop, ensuring stable and reliable operation.

[0057] The silver spot shearing force detection mechanism is used to apply a certain pressure to the workpiece to detect whether the silver spot is poorly welded and to provide feedback to the PLC controller. The mechanism includes a cylinder shearing motion device and a pressure sensor; the cylinder's output shaft is connected to the pressure sensor. The cylinder drives the pressure sensor with a set pressure value, and the pressure sensor feeds back the actual detected pressure value to the PLC controller to determine whether the workpiece is qualified. The mechanism determines the shearing force required to push the silver spot by adjusting the air pressure. If the weld is not strong or the shearing force is insufficient, the silver spot will be pushed off without any shearing force feedback. The system determines this as a defective product and will directly shear it off at the shearing station. If the shearing force fails repeatedly, the system will automatically stop and alarm.

[0058] The online size and appearance inspection mechanism is used to acquire images of the workpiece, analyze and process the size information of the images, and transmit the processing result signal to the PLC controller. The online size and appearance inspection mechanism includes a CCD image processor, a bracket, a display, and a camera. The camera, display, and CCD image processor are mounted on the bracket. The camera is connected to the CCD image processor and located above the workpiece. The CCD image processor is connected to both the PLC controller and the display. The bracket serves to fix the camera, display, and CCD image processor; the camera's function is to acquire images of the workpiece; the CCD image processor's function is to analyze and process the size information of the images and transmit the processing result signal to the PLC; the display is responsible for displaying the CCD image processor interface and serves as the human-machine interface window.

[0059] The online size and appearance inspection mechanism is mainly used when the equipment is running normally. If a defective product is detected, it is first marked as an NG (Not Good) product. In the subsequent defective product shearing station, it is directly sheared and separated to avoid edge material or waste material from being mixed with normal good products. If the equipment continuously produces defective products, the system will automatically stop the machine and alarm.

[0060] The shearing device receives signals from the PLC controller and is responsible for cutting off defective workpieces. The shearing device includes a cylinder and a cutting blade motion mechanism; the cylinder provides power to the cutting blade; the cutting blade is responsible for cutting off non-compliant products.

[0061] The copper strip feeding device receives signals from the PLC controller and is responsible for feeding the copper strip. The device includes a servo controller, a servo motor, and a feeding roller. The outputs of the servo controller and servo motor are connected to the feeding roller, which clamps the copper strip. The feeding roller is responsible for clamping the copper strip and rolling it for feeding; the servo motor and servo controller are responsible for precisely rotating according to the set feeding length, driving the feeding roller to complete the copper strip feeding.

[0062] This invention also discloses an operation method for an automatic welding system for silver-based alloy materials based on visual inspection. After blanking and stamping, the formed copper strip enters the copper strip positioning station, welding station, silver point shearing force detection station, appearance dimension detection station, shearing station and copper strip feeding station in sequence through the feeding tray, and finally enters the receiving tray.

[0063] Specifically, the following steps are included:

[0064] (1) The PLC controller sends a signal to the copper strip servo controller to start the motor and drive the feeding roller to feed the copper strip; the PLC controller controls the positioning cylinder to push the positioning pin to position and fix the copper strip; at the same time, the PLC controller sends a signal to the silver strip servo controller to start the servo motor to drive the cam feeder to feed the silver strip. When the welding silver point is transported to the welding station, the PLC controller sends a signal to the medium frequency inverter power supply to perform discharge welding.

[0065] (2) After the welding action is completed, the copper strip moves down one station and enters the silver point shear force detection station. The PLC controller sends a signal to the cylinder of the silver point shear force detection mechanism. The cylinder drives the pressure sensor with a set pressure value. The pressure sensor feeds back the actual detected pressure value to the PLC controller to determine whether the silver point of the workpiece is poorly welded. If there is a poor weld, it is marked as NG.

[0066] (3) After the shear force test is completed, the copper strip is moved to the appearance and size inspection station. The PLC controller sends a signal to the online size and appearance inspection mechanism, and the relevant defects are identified by CCD image detection. If there are defects, they are marked as NG.

[0067] (4) After completing the online image detection, the product enters the shearing station. If the station in step (2) and / or step (3) detects that the product is marked as NG, the PLC controller sends a signal to the shearing device, and its cylinder pushes the cutter to cut off the NG product, so as to prevent the defective product from entering the good product; the welding and quality inspection of the workpiece are completed; each movement of the copper strip is controlled by the copper strip feeding device.

[0068] The touch screen of this invention provides settings for welding parameters, station movement angles, number of electrode replacement points, and welding speed. The touch screen allows for convenient and flexible setting of welding process parameters for each material, improving the versatility of the equipment.

[0069] As a preferred embodiment, the implementation process of step (3) includes the following steps:

[0070] The implementation process of step (3) includes the following steps:

[0071] (31) CCD settings: 2432*2050 pixels, 1KHz sampling frequency, and external terminal triggering (PLC output triggering).

[0072] (32) Image Registration: Manually trigger a photograph of a normal, intact sample, and save the acquired template image to a specified document named ref1_000.bmp, such as... Figure 3 As shown. The main function of the registered images is to provide fast matching for subsequent detection.

[0073] (33) Window Settings: A core function of image processing. To effectively check the measured size of the silver point, this invention uses three feature points along the X-axis for window recognition settings, namely X1, X2, and X3. All three windows use image detection tools at edge positions. The filter algorithm for X1 is contrast conversion and binarization; the filter processing results are as follows: Figure 4 , Figure 5 As shown.

[0074] After filtering, the current X-axis pixel value is 441.215; that is, X1 = 441.215. The filter algorithm for X2 is contrast conversion and averaging; the values ​​before and after filtering are as follows. Figure 6 , Figure 7 As shown.

[0075] After filtering, the current X-axis pixel value is 835.362; that is, X2 = 835.362. The filter algorithm for X3 is contrast conversion and shrinkage; the values ​​before and after filtering are as follows. Figure 8 , Figure 9 As shown.

[0076] After processing with the filter, the current X-axis pixel value is 1235.825; that is, X3 = 1235.825. To calculate the pixel value along the X-axis of the silver dot, ΔX = X3 - X2.

[0077] (34) Position Correction: This tool is mainly used to correct the workpiece image when it is offset by the selected reference. For example, with X1 as the reference position, X2 and X3 are corrected with X1 as the reference. After the sampled image is offset, it can also be corrected according to the X1 position, so that the relative position between X2 and X3 is kept on the same X-axis.

[0078] (35) Calculation: The image processor provides calculation functions. After obtaining the values ​​of X1, X2, and X3 from step 4, to calculate the pixel value (size) of the silver point on the workpiece in the X-axis direction, the formula in the calculation tool can be used:

[0079] ΔX = X3 - X2 = 1235.825 - 835.362 = 400.463. At this point, it is necessary to set the upper and lower tolerance limits for ΔX. Generally, the setting is determined according to the actual production process.

[0080] (36) Output setting: Select “Comprehensive judgment (OR terminal)” and select ΔX output. When the actual size exceeds the ΔX tolerance range, the image processor hardware output port will transmit the NG signal to the PLC for subsequent processing.

[0081] (37) Continuous detection: After completing the settings of the first 6 steps, the image processor has completed the relevant size detection settings and can run the detection continuously. When the copper strip runs to the size and appearance online detection station during the welding process, the PLC control system triggers the CCD camera to take pictures through the transistor output port, acquires the original image of the current workpiece, and then performs template matching, position correction, calculation and output settings in the window settings to realize the image processing function of the present invention.

[0082] In a preferred embodiment, in step (4), the operation method of the servo motor encoder in the copper strip feeding device is as follows: during the copper strip feeding process, the servo motor encoder corresponding angle starts from 0° and ends at 60°; during the copper strip positioning process, the servo motor encoder corresponding angle starts from 61° and ends at 85°; then, the silver point feeding and silver point feeding arrival detection is performed, with the servo motor encoder corresponding angle starting from 86° and ending at 160°; next, the silver point welding is performed, with the servo motor encoder corresponding angle starting from 161° and ending at 200°; then, the shearing force detection is performed, with the servo motor encoder corresponding angle starting from 201° and ending at 240°; then, the CCD image detection is performed, with the servo motor encoder corresponding angle starting from 241° and ending at 300°; finally, the top dead point detection is performed, with the servo motor encoder corresponding angle starting from 301° and ending at 360°. Through the design of motion control, the action rhythm of the equipment is precisely and efficiently controlled, completing the fully automatic welding process.

[0083] The above embodiments are merely specific examples to further illustrate the purpose, technical solution, and beneficial effects of the present invention, and the present invention is not limited thereto. Any modifications, equivalent substitutions, improvements, etc., made within the scope of the disclosure of the present invention are included within the protection scope of the present invention.

Claims

1. An automatic welding equipment for silver-based alloy materials based on vision inspection, characterized in that: This includes a PLC controller, and components arranged sequentially from the feeding tray to the receiving tray. A copper strip positioning device is used to receive signals from the PLC controller and to position and fix the copper strip. The welding mechanism includes a silver strip feeding device and an upper and lower electrode welding device. The silver strip feeding device is used to receive signals from the PLC controller and provide silver strip feeding function; the upper and lower electrode welding device is used to receive signals from the PLC controller and work together with the silver strip feeding device to perform silver point contact discharge welding. The silver spot shear force detection mechanism is used to apply a certain pressure to the workpiece to detect whether the silver spot is poorly soldered, and then feeds back to the PLC controller. The online size and appearance inspection mechanism is used to acquire images of workpieces, analyze and process the size information of the images, and transmit the processing result signal to the PLC controller. The shearing device receives signals from the PLC controller and is responsible for cutting off defective workpieces; The copper strip feeding device receives signals from the PLC controller and is responsible for feeding the copper strip. The power system of the upper and lower electrode welding device mainly consists of a medium-frequency inverter controller and a transformer. The medium-frequency inverter controller includes a three-phase power input module, an IGBT module, a power drive module, a main control board, and a programmer. The transformer includes a secondary current transformer, a temperature sensor, and a transformer coil. AC 380V power is input to the three-phase power input module, converted to DC power input to the IGBT module. The IGBT module is driven by the power drive module controlled by the main control board. The two outputs of the IGBT module are connected to the input terminals of the transformer coil via secondary current transformers, and the output terminals of the transformer coil are connected to the upper and lower electrodes via secondary current transformers. The two outputs of the IGBT module are also connected to the main control board via secondary current transformers. The temperature sensor detects the transformer current and inputs it to the main control board. The welding secondary current detected by the secondary current transformer is input to the main control board. The main control board also communicates with the programmer and the PLC controller. The operation method of the servo motor encoder in the copper strip feeding device is as follows: During the copper strip feeding process, the servo motor encoder angle starts from 0° and ends at 60°; during the copper strip positioning process, the servo motor encoder angle starts from 61° and ends at 85°; then, the silver point feeding and silver point feeding position detection are performed, with the servo motor encoder angle starting from 86° and ending at 160°; next, the silver point welding is performed, with the servo motor encoder angle starting from 161° and ending at 200°; then, the shearing force detection is performed, with the servo motor encoder angle starting from 201° and ending at 240°; next, CCD image detection is performed, with the servo motor encoder angle starting from 241° and ending at 300°; finally, the top dead point detection is performed, with the servo motor encoder angle starting from 301° and ending at 360°.

2. The automatic welding equipment for silver-based alloy materials based on vision inspection according to claim 1, characterized in that: The copper strip positioning device includes two U-shaped detection sensors, a positioning pin, a positioning cylinder, and a mechanical fixing mechanism. The positioning cylinder is mounted on the mechanical fixing mechanism, the positioning pin is connected to the output of the positioning cylinder and is located below the copper strip, and the U-shaped detection sensors are mounted on the positioning cylinder to detect the position of the cylinder's movement.

3. The automatic welding equipment for silver-based alloy materials based on vision inspection according to claim 1, characterized in that: The silver belt feeding device includes a servo controller and a servo motor, a transmission coupling, and a cam feeder. The output shafts of the servo controller and the servo motor are connected to the cam feeder via the transmission coupling, and the cam feeder is connected to the silver belt.

4. The automatic welding equipment for silver-based alloy materials based on vision inspection according to claim 1, characterized in that: The silver point shear force detection mechanism includes a cylinder and a pressure sensor, both of which are connected to a PLC controller. The output of the cylinder is connected to the pressure sensor.

5. The automatic welding equipment for silver-based alloy materials based on vision inspection according to claim 1, characterized in that: The online size and appearance inspection mechanism includes a CCD image processor, a bracket, a display, and a camera. The camera, display, and CCD image processor are mounted on the bracket. The camera is connected to the CCD image processor and is located above the workpiece. The CCD image processor is connected to the PLC controller and the display, respectively.

6. The automatic welding equipment for silver-based alloy materials based on vision inspection according to claim 1, characterized in that: The copper strip feeding device includes a servo controller and a servo motor, and a feeding roller. The output ends of the servo controller and the servo motor are connected to the feeding roller, and the feeding roller clamps the copper strip to achieve rolling feeding of the copper strip.

7. An operation method for an automatic welding equipment for silver-based alloy materials based on vision inspection, employing the automatic welding equipment for silver-based alloy materials as described in any one of claims 1 to 6, characterized in that, Includes the following steps: (1) Position the copper strip, and then transport the silver spot to be welded to the welding station for electrical discharge welding; (2) After the welding action is completed, the copper strip moves down one station and enters the silver point shear force detection station. Each time, a certain pressure is applied to check whether the silver point is poorly welded. If there is a poor weld, it is marked as NG. (3) After the shear force test is completed, the copper strip is moved to the appearance and size inspection station. The relevant defects are identified by CCD image detection. If there are defects, they are marked as NG. (4) After completing the online image detection, the product enters the shearing station. If the station in step (2) and / or step (3) detects that the product is marked as NG, the workpiece marked as NG is cut off at this station to prevent defective products from entering the good products; the welding and quality inspection of the workpiece are completed; each movement of the copper strip is controlled by the copper strip feeding device.

8. The operation method of the automatic welding equipment for silver-based alloy materials based on vision inspection according to claim 7, characterized in that: The implementation process of step (3) includes the following steps: (31) CCD settings: Set the pixel count and sampling frequency respectively; (32) Register images: Manually trigger the taking of pictures of normal and intact samples, save the collected template images, and provide rapid matching for subsequent detection; (33) Window settings: Take three feature points in the X-axis direction for window recognition settings, namely X1, X2 and X3; all three windows use the image detection tool at the edge position, and the filter algorithm of X1 is contrast conversion and binarization; The current X-axis pixel value is obtained after filtering; the filter algorithm for X2 is contrast conversion and averaging. The current X-axis pixel value is obtained after filtering; the filter algorithm for X3 is contrast conversion and shrinkage. After processing with a filter, the current X-axis pixel value is obtained as X3. The pixel value of the silver point in the X-axis direction is calculated as follows: ΔX = X3 - X2. (34) Position correction: When the workpiece image is offset, a reference correction is performed; with X1 as the reference position, X2 and X3 are corrected with X1 as the correction reference. After the sampled image is offset, it is corrected according to the X1 position so that the relative positions between X2 and X3 are kept on the same X-axis. (35) Calculation: After obtaining the values ​​of X1, X2 and X3 from step (33), the pixel value of the silver point in the X-axis direction on the workpiece needs to be calculated. The calculation formula is: ΔX=X3-X2. At this time, the upper and lower tolerance limits of ΔX need to be set. (36) Output setting: Select ΔX output. When the actual size exceeds the ΔX tolerance range, the image processor hardware output port will transmit the NG signal to the PLC controller for subsequent processing. (37) Continuous detection: After completing the settings of the first 6 steps, the image processor has completed the settings for the relevant size detection and can run the detection continuously; when the copper strip runs to the size and appearance online detection station during the welding process, the PLC controller triggers the CCD camera to take pictures through the transistor output port, collects the original image of the current workpiece, and then performs template matching, position correction, calculation and output settings in the window settings.

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