CN115178909B - Welding quality detection method and device, terminal equipment and medium - Google Patents

Abstract

The invention discloses a welding quality detection method, a device, terminal equipment and a medium, wherein the method comprises the following steps: the method comprises the steps of obtaining the solder usage volume of a target welding spot and the solder overflow volume corresponding to the target welding spot, calculating the solder filling volume based on the solder usage volume and the solder overflow volume, judging the welding quality of the target welding spot based on the solder filling volume and the target filling volume, and reducing the detection difficulty and improving the detection coverage rate on the premise of ensuring the validity of a detection result.

Description

Welding quality testing methods, devices, terminal equipment and media

Technical field

The invention relates to the field of welding, and in particular to a welding quality detection method, device, terminal equipment and medium.

Background technique

Brazing is a connection method that uses solder with a lower melting temperature than the base metal. The heating temperature is lower than the solidus line of the base metal and higher than the liquidus line of the solder. Electronic assembly uses tin alloy as the soldering material. Achieve connection strength and electrical conduction.

For example, in frequency converters, servo drives, elevator cabinets and other products, IGBT (Insulated Gate Bipolar Transistor) are all welded on the entire machine assembly line. The brazing method is usually automatic spot welding, that is, by controlling the welding of automated equipment. Process control is carried out over time. After brazing and welding are completed, manual visual inspection is used to inspect the appearance of the solder joints and audit the quality of the solder joints. At the same time, the products will be randomly inspected, that is, the PCBA (Printed Circuit Board Assembly, printed circuit board) motherboard will be disassembled from the complete welded product, and the PCBA motherboard will be placed into an x-ray machine for x-ray inspection. The test results review the solder joint quality, and then the PCBA motherboard is installed back into the complete product after review.

The quality of the solder joints is not guaranteed by controlling the welding time. In this method, there may be only a small amount of tin alloy on the surface of the solder joints, and there is not enough tin alloy in the through holes of the solder joints to contact the pins, resulting in electrical failure of the solder joints. The characteristics are unstable. Even if manual visual inspection is performed after welding, manual visual inspection can only detect the appearance of the solder joints and cannot judge the tin filling situation in the through holes, that is, it cannot detect the tin filling height in the solder joint through holes. Therefore, The quality of solder joints cannot be guaranteed; the filling of tin alloy in the solder joint through holes can be detected using The sample cannot represent the entire product to a certain extent.

To sum up, all current solder joint quality inspection methods either cannot detect the actual solder joint quality, or the detection coverage is low due to high cost, and the detection results are not highly representative.

Contents of the invention

The main purpose of the present invention is to provide a welding quality detection method, device, terminal equipment and medium, aiming to solve the problem of how to reduce the difficulty of detection while ensuring the validity of the detection results during the whole machine welding process, thereby improving detection Technical issues with coverage.

In order to achieve the above object, the present invention provides a method for detecting welding quality. The method for detecting welding quality includes the following steps:

Obtain the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint, and calculate the solder filling volume based on the solder usage volume and the solder overflow volume;

Based on the solder filling volume and the target filling volume, the welding quality of the target solder joint is determined.

Optionally, the step of obtaining the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint also includes:

Obtain the welding time of the target solder joint;

If the target welding time is greater than the preset welding time threshold, then perform the steps of: obtaining the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point, and based on the solder usage volume and the solder overflow volume, Calculate solder fill volume.

Optionally, the step of obtaining the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint includes:

Use a camera to monitor the volume change of the solder ball formed during the contact between the solder corresponding to the target solder joint and the soldering head;

The maximum volume of the solder ball is used as the solder usage volume, and the volume of the solder ball outside the through hole corresponding to the target solder point is used as the solder overflow volume.

Optionally, the step of obtaining the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint also includes:

Obtain the welding time of the target solder joint;

If the target welding time is less than or equal to the preset welding time threshold, then perform the steps of: obtaining the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point, and based on the solder usage volume and solder overflow Volume, calculate the solder fill volume.

Optionally, the step of obtaining the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint includes:

Obtain the cross-sectional area of the solder corresponding to the solder joint and the usage length of the solder, and calculate the current solder usage volume based on the cross-sectional area and the usage length;

After the target solder point is welded, the solder overflow volume corresponding to the target solder point is obtained.

Optionally, the step of judging the welding quality of the target solder joint based on the solder filling volume and the target filling volume also includes:

Obtain the supplementary coefficient corresponding to the target solder joint;

The step of judging the welding quality of the target solder joint based on the solder filling volume and the target filling volume includes:

Based on the solder filling volume corresponding to the solder joint, the target filling volume and the supplementary coefficient, the current filling height is calculated, and based on the current filling height, the welding quality of the target solder joint is judged.

Optionally, the step of calculating the solder filling volume based on the solder usage volume and the solder overflow volume includes:

Obtain the solder quality fraction corresponding to the target solder joint;

Based on the solder usage volume, the solder overflow volume and the solder mass fraction, the current solder filling volume is calculated.

In addition, to achieve the above object, the present invention also provides a device for detecting welding quality. The device for detecting welding quality includes:

The acquisition module is used to obtain the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint, and calculate the solder filling volume based on the solder usage volume and the solder overflow volume;

A calculation module configured to determine the welding quality of the target solder joint based on the solder filling volume and the target filling volume.

In addition, in order to achieve the above object, the present invention also provides a terminal device, which includes a memory, a processor, and a welding quality detection program stored in the memory and executable on the processor. When the welding quality detection program is executed by the processor, the steps of the welding quality detection method as described above are implemented.

In addition, to achieve the above object, the present invention also provides a computer-readable storage medium, the computer-readable storage medium stores a welding quality detection program, and when the welding quality detection is executed by the processor, the above-mentioned The steps of welding quality detection method.

The present invention provides a welding quality detection method, device, terminal equipment and medium. By obtaining the solder usage volume of a target solder joint and the solder overflow volume corresponding to the target solder joint, and based on the solder usage volume and the solder The overflow volume is used to calculate the solder filling volume, and based on the solder filling volume and the target filling volume, the welding quality of the target solder joint is judged, which solves the problem that manual visual inspection cannot detect the filling height of the target solder joint, and this application The cost of filling height detection is greatly reduced compared to the detection cost of X-Ray machines. It can be applied to large-scale product inspection and improves the detection coverage.

Description of the drawings

Figure 1 is a schematic diagram of the functional modules of the terminal equipment belonging to the welding quality detection device of this application;

Figure 2 is a schematic flow chart of an exemplary embodiment of the welding quality detection method of the present application;

Figure 3 is a schematic flow chart of another exemplary embodiment of the welding quality detection method of the present application;

Figure 4 is a schematic flow chart of another exemplary embodiment of the welding quality detection method of the present application;

Figure 5 is a schematic flow chart of another exemplary embodiment of the welding quality detection method of the present application;

Figure 6 is a schematic flow chart of another exemplary embodiment of the welding quality detection method of the present application;

Figure 7 is a schematic flow chart of another exemplary embodiment of the welding quality detection method of the present application;

Figure 8 is a schematic flow chart of another exemplary embodiment of the welding quality detection method of the present application;

Figure 9 is a schematic diagram of part of the mechanism of the automatic spot welding machine involved in the welding quality detection method of this application;

Figure 10 is a schematic diagram before and after welding involved in the welding quality detection method of this application.

The realization of the purpose, functional features and advantages of the present invention will be further described with reference to the embodiments and the accompanying drawings.

Detailed ways

It should be understood that the specific embodiments described here are only used to explain the present invention and are not intended to limit the present invention.

The main solution of the embodiment of the present invention is to obtain the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point, and calculate the solder filling volume based on the solder usage volume and the solder overflow volume. The solder filling volume and the target filling volume are used to determine the welding quality of the target solder joint. Based on this application plan, from the perspective of current difficulty and high cost of complete machine detection, combined with visual capture computing technology, an effective complete machine detection method is provided. Compared with existing detection methods, this detection method greatly reduces the detection time. cost, so that it can be applied to detect large-scale products and improve detection coverage.

Relevant background involved in the embodiments of this application

Referring to Figure 9, Figure 9 is a partial structural diagram of an automatic spot welding machine involved in the welding quality detection method of the present application. The automatic spot welding machine includes: a hanging fixture 10, a welding machine handle 20, an industrial camera 30, and a tin feeding pipe 40 , the motherboard PCBA is 50, and the product is 60.

Referring to Figure 10, Figure 10 is a schematic diagram before and after welding (shown in Figure a) and after (shown in Figure B) involved in the welding quality detection method of the present application, in which 1 is the tin wire, 2 is the input solder, and 3 is For the soldering iron tip, 4 is the main board PCBA, 5 is the through hole, 6 is the component pin, and 7 is the solder after welding.

With the extensive application of robots in the field of industrial automation, visual systems have also been extensively developed and used as the "eyes" of automation equipment. The vision system combines visual inspection technology and industrial robot kinematics principles, aiming to install "eyes" on the robot, breaking through the limitation that the robot can only repeat the teaching trajectory, so that it can adjust the working trajectory in real time according to changes in the workpiece being operated. Promote production efficiency and improve production quality.

Specifically, refer to FIG. 1 , which is a schematic diagram of the functional modules of the terminal equipment to which the welding quality detection device of the present application belongs. The welding quality inspection device can be a device that is independent of the terminal equipment and can obtain the solder usage volume, obtain the solder overflow volume, calculate the solder filling volume, calculate the filling height, and judge the solder joint quality. It can be done through hardware or The form of software is carried on the terminal device. The terminal device can be a smart mobile terminal with data processing functions such as a mobile phone or a tablet computer, or a fixed terminal device or server with data processing functions.

In this embodiment, the terminal equipment to which the welding quality detection device belongs includes at least an output module 110, a processor 120, a memory 130 and a communication module 140.

The memory 130 stores an operating system and a program for welding quality inspection. The device for welding quality inspection can store information such as solder usage volume, solder overflow volume, solder filling volume, target filling volume, filling height, etc. in the memory 130; the output module 110 can be a display screen, etc. The communication module 140 may include a WIFI module, a mobile communication module, a Bluetooth module, etc., and communicates with external devices or servers through the communication module 140 .

Wherein, when the welding quality detection program in the memory 130 is executed by the processor, the following steps are implemented:

Obtain the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint, and calculate the solder filling volume based on the solder usage volume and the solder overflow volume;

Based on the solder filling volume and the target filling volume, the welding quality of the target solder joint is determined.

Further, when the welding quality detection program in the memory 130 is executed by the processor, the following steps are also implemented:

Obtain the welding time of the target solder joint;

If the target welding time is greater than the preset welding time threshold, then perform the steps of: obtaining the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point, and based on the solder usage volume and the solder overflow volume, Calculate solder fill volume.

Further, when the welding quality detection program in the memory 130 is executed by the processor, the following steps are also implemented:

Use a camera to monitor the volume change of the solder ball formed during the contact between the solder corresponding to the target solder joint and the soldering head;

The maximum volume of the solder ball is used as the solder usage volume, and the volume of the solder ball outside the through hole corresponding to the target solder point is used as the solder overflow volume.

Further, when the welding quality detection program in the memory 130 is executed by the processor, the following steps are also implemented:

Obtain the welding time of the target solder joint;

If the target welding time is less than or equal to the preset welding time threshold, then perform the steps of: obtaining the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point, and based on the solder usage volume and solder overflow Volume, calculate the solder fill volume.

Further, when the welding quality detection program in the memory 130 is executed by the processor, the following steps are also implemented:

Obtain the cross-sectional area of the solder corresponding to the solder joint and the usage length of the solder, and calculate the current solder usage volume based on the cross-sectional area and the usage length;

After the target solder point is welded, the solder overflow volume corresponding to the target solder point is obtained.

Further, when the welding quality detection program in the memory 130 is executed by the processor, the following steps are also implemented:

Obtain the supplementary coefficient corresponding to the target solder joint;

Based on the solder filling volume corresponding to the solder joint, the target filling volume and the supplementary coefficient, the current filling height is calculated, and based on the current filling height, the welding quality of the target solder joint is judged.

Further, when the welding quality detection program in the memory 130 is executed by the processor, the following steps are also implemented:

Obtain the solder quality fraction corresponding to the target solder joint;

Based on the solder usage volume, the solder overflow volume and the solder mass fraction, the current solder filling volume is calculated.

The present invention provides a welding quality detection method, device, terminal equipment and medium. By obtaining the solder usage volume of a target solder joint and the solder overflow volume corresponding to the target solder joint, and based on the solder usage volume and the solder The overflow volume is used to calculate the solder filling volume. Based on the solder filling volume and the target filling volume, the welding quality of the target solder joint is judged. By combining industrial vision, the welding quality of the whole machine is ensured and the welding quality is provided. An effective detection method for welding quality. Compared with existing detection methods, this detection method is simple to operate, safe in the detection process, and lower in cost. Ultimately, it improves the detection efficiency while ensuring the validity of the detection results. coverage effect.

Based on the above terminal device architecture but not limited to the above architecture, method embodiments of the present application are proposed.

Referring to Figure 2, Figure 2 is a schematic flow chart of an exemplary embodiment of the welding quality detection method of the present application. The welding quality detection method includes:

Step S1001, obtain the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point, and calculate the solder filling volume based on the solder usage volume and the solder overflow volume;

The solution of this embodiment is applied to the automatic spot welding machine to realize the welding quality detection of the product.

Specifically, the solder usage volume refers to the solder volume actually used by the target solder joint on the product, which can reflect the actual solder usage of the solder joint. Refer to Figure 10, label 2 is the solder usage volume.

The solder overflow volume refers to the volume of solder outside the through hole of the target solder joint after the target solder joint is soldered. By subtracting the solder overflow volume from the solder usage volume, we can obtain the volume of solder filled within the through hole after welding is completed, that is, the solder filling volume. Refer to Figure 10, number 7 is the solder overflow volume.

Example 1: After the welding of the target solder joint is started, the solder, that is, the solder is sent to the target solder joint through the robot arm, and the temperature is raised to the melting point by heating, and then melted. In this embodiment, a tin-based solder is used as an example of the solder. The melting point of tin is usually 183-227°C. The following example will use 220°C as the melting point of tin wire. After heating, the tin wire becomes liquid and converges into a spherical shape due to the tension of the liquid, forming a tin ball.

Due to continuous heating, the solder balls formed become larger and larger, and because the temperature of the PCBA motherboard has not yet reached 220°C, no tin will fall into the through holes of the target solder joints until the volume of the solder balls increases to the maximum. , where the solder ball volume is the actual solder volume. After the solder ball volume reaches the maximum, the temperature of the target solder joint of the PCBA motherboard also reaches 220°C, that is, it reaches the melting point of tin, but does not reach the melting point of the PCBA motherboard. At this time, the solder ball falls into the through hole.

Among them, when the volume of the solder ball is less than the volume of the through hole, the tin filling height in the through hole is less than the height of the through hole, that is, less than the thickness of the PCBA motherboard, and the through hole is in an unfilled state; when the volume of the solder ball is greater than the volume of the through hole, the through hole is in an unfilled state. The hole is filled with tin, and the excess overflows on the solder joint. The excess is the solder overflow volume.

The solder usage volume and solder overflow volume are captured through industrial cameras, and corresponding pixel images are generated. Then through visual calculation, the values of the solder usage volume and the solder overflow volume can be obtained. Finally, the solder usage volume value is subtracted from the solder. The value of the overflow volume is the value of the solder filling volume.

Example 2. This example uses tin-based solder as the solder. The welding process is captured by an industrial camera to obtain a pixel image corresponding to the real-time welding process. When the solder ball increases to the maximum, the solder ball on the pixel image is obtained. The number of pixels occupied by the diameter, combined with the pixel scale in visual calculations, can be used to obtain the corresponding volume value of the maximum volume of the solder ball, that is, the solder usage volume. After the solder ball partially falls into the through hole, the volume of the tin outside the through hole gradually decreases until it fills the through hole. The volume of the tin outside the through hole shrinks to the minimum. By acquiring the corresponding pixel image, the volume outside the through hole is The solder overflow volume can be obtained by converting the pixel area occupied by tin when it is at its minimum volume.

Example 3: This example uses tin-based solder as the solder. After welding the target solder joint, calculate the volume of the tin wire used. Specifically, calculate the cross-sectional area of the tin wire and compare the cross-sectional area with the length used. Multiply to get the value of the volume used by the tin wire, that is, the value of the volume used by the solder. Then use an industrial camera to obtain the pixel area occupied by the tin outside the through-hole on the corresponding pixel image when the volume of the tin outside the through-hole shrinks to the minimum. After conversion, the value of the solder overflow volume can be obtained. Finally, subtract the value of the solder overflow volume from the value of the solder usage volume, and the obtained value is the value of the solder filling volume.

In the above Example 2 and Example 3, the method of obtaining the solder overflow volume is the same, but the method of obtaining the solder usage volume is different. Among them, Example 2 is obtained using the dynamic method, that is, the entire welding process of the target solder joint is monitored in real time through an industrial camera. Example 3 is obtained using the static method, that is, after the welding of the target solder joint is completed, the reduced volume of the tin wire in the tin feeding pipe is calculated as the solder usage volume.

Step S1002: Determine the welding quality of the target solder joint based on the solder filling volume and the target filling volume.

First of all, the pre-entered target filling volume refers to the remaining volume in the through hole after the through hole of the target soldering point is welded into the part foot, that is, the through hole volume minus the volume corresponding to the welded part foot is the target filling volume. Among them, the mathematical formula of the target filling volume is expressed as:

Among them, T represents the thickness of the PCBA motherboard, that is, the height of the target solder joint through hole, Indicates the through hole diameter of the target solder joint,/> Indicates the diameter of the foot of the welded part. Since the remaining volume after the through hole is welded into the part foot is a hollow cylinder, the surface area of the through hole is calculated/> Subtract the surface area of the pin/> Find the base surface area of the hollow cylinder Then multiply the bottom surface area of the hollow cylinder by the height of the hollow cylinder, that is, the thickness T of the PCBA motherboard, to obtain the volume of the hollow cylinder, which is the target filling volume.

Specifically, after the solder filling volume is obtained through step S1001, combined with the pre-input target filling volume, the specific calculation is to divide the solder filling volume by the target filling volume to obtain a percentage. The percentage represents that the through hole is soldered into the part. After the foot, the filling degree of the solder in the through hole is obtained by multiplying the percentage and the through hole height T to obtain the value of the filling height. The value of the filling height is compared with the value of the target filling height. If the filling height If the value is less than the target filling height, the welding quality test result is unqualified. If the filling height value is greater than or equal to the target filling height value, the welding quality test result is qualified. Among them, the filling height value is greater than When setting the value of the target filling height, the larger part cannot exceed the preset range. Usually, the preset range is 10% of the target filling height.

Furthermore, since the remaining volume after the through hole is soldered into the part foot is the volume corresponding to a hollow cylinder, the filling height can be obtained by dividing the solder filling volume by the bottom area of the hollow cylinder. The mathematical expression is: Provide another algorithm that can obtain the fill height without obtaining the thickness T of the PCBA motherboard.

In this embodiment, through the above solution, specifically, the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point are obtained, and based on the solder usage volume and the solder overflow volume, the solder filling volume is calculated, and the solder filling volume is obtained. The target filling volume corresponding to the target solder joint, based on the solder filling volume and the target filling volume, determines the welding quality of the target soldering point, obtains the corresponding numerical value, and performs corresponding calculations to finally obtain the specific numerical value of the filling height, As one of the standards for judging welding quality, it provides an effective whole-machine inspection method. Compared with existing inspection methods, this inspection method greatly reduces the inspection cost, so it can be applied to inspect large-scale products and improve inspection. coverage.

Referring to Figure 3, Figure 3 is a schematic flow chart of another exemplary embodiment of the welding quality detection method of the present application. In step S1001, the step of obtaining the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point also includes:

Step A100, obtain the welding time of the target solder joint;

This embodiment explains the dynamic method for obtaining the solder usage volume.

Specifically, the welding time refers to the time for welding the target solder joint, and the length of time is selected according to the thickness, material, etc. of the solder. According to the different welding times of different products, different methods are used to obtain the solder volume of different products. For example, products with a longer welding time usually use a larger solder volume, while products with a shorter welding time usually focus on the welding volume. Accuracy: According to the different welding times of different products, different acquisition methods are used for the solder volume of different products, thereby improving the acquisition efficiency and thus improving the detection efficiency of solder joint quality.

Step A200, if the target welding time is greater than the preset welding time threshold, perform the steps of: obtaining the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point, and based on the solder usage volume and solder Overflow volume, calculate solder filling volume;

Specifically, when the welding time of product A is greater than the preset welding time threshold, the solder usage volume and solder overflow volume of product A are obtained using a dynamic method, that is, the entire welding process of the target solder joint is monitored in real time through an industrial camera, and in the corresponding frame In the pixel image, according to the pixel area occupied by the solder, the solder usage volume and solder overflow volume are obtained.

This embodiment adopts the above solution, specifically by obtaining the welding time of the target solder point. If the target welding time is greater than the preset welding time threshold, then perform the steps of: obtaining the solder usage volume of the target solder point, and the target solder joint. Point corresponding solder overflow volume, and calculate the solder filling volume based on the solder usage volume and solder overflow volume. Different actual filling volume calculation methods are used for different products corresponding to different welding times, because electronic products with longer welding times Electronic products that are more inclined to ensure the amount of tin used and have shorter welding times are more inclined to ensure the accuracy of welding. According to these different points, different calculation methods are used for the actual filling volume, which improves the calculation efficiency and thus improves the detection of welding quality. efficiency.

Referring to Figure 4, Figure 4 is a schematic flow chart of another exemplary embodiment of the welding quality detection method of the present application. Step S1001, the steps of obtaining the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point include:

This embodiment further explains the dynamic method in the embodiment corresponding to FIG. 3 .

Step A201, monitor the volume change of the solder ball formed during the contact between the solder corresponding to the target solder point and the soldering head through a camera;

Specifically, in this embodiment, 3 seconds is used as the preset welding time. When the welding time of product A is greater than 3 seconds, the solder usage volume of product A is obtained by dynamic acquisition. Dynamic acquisition means that through The industrial camera dynamically captures the entire process of welding the target solder point of Product A in real time, that is, the volume change process of the solder ball formed during the contact between the solder corresponding to the target solder point and the welding head, and converts the captured process into a frame. Frame image information, based on the pixel area occupied by the volume of the solder ball in the image of the corresponding frame, combined with the pixel scale, the solder usage volume and solder overflow volume of product A can be obtained through a visual algorithm.

Among them, the solder usage volume refers to the largest solder ball volume before the solder ball falls into the through hole of the target solder point. The solder overflow volume refers to the solder ball filling the through hole after falling into the target solder point through hole. During the process, when the volume of solder outside the through hole continues to decrease, it reaches the minimum volume.

More specifically, first, the industrial camera obtains the pixel image generated when the standard ruler is at a preset distance, where the preset distance is the distance between the industrial camera and the target solder joint. By dividing the length of the standard ruler by the pixel image of the standard ruler The number of pixels occupied in the distance is obtained to obtain the pixel scale at the preset distance, that is, the actual length represented by each pixel is obtained.

Then, using tin-based solder as the solder, the volume change process of the solder ball formed during the contact between the solder and the soldering head is as follows. The tin-wire-shaped tin-based solder melts to form a tin ball, that is, a solder ball. Due to continuous heating , the tin wire continues to melt before reaching the preset usage value, so the solder ball formed becomes larger and larger. Since the temperature of the PCBA motherboard has not yet reached 220°C, there will be no part of the tin ball before the volume increases to the maximum. After falling into the through hole of the target solder joint, the solder ball volume reaches the maximum, and the temperature of the target solder joint on the PCBA motherboard also reaches 220°C. At this time, the solder ball falls into the through hole. When the solder ball volume is larger than the through hole volume, The solder balls fill the through holes and the excess overflows on the solder joints.

Among them, through the infrared temperature sensing function in the industrial camera, the volume area in a fixed area is collected, and the volume change of the solder ball formed during the contact between the solder and the soldering head is accurately obtained. By emitting infrared radiation energy, the infrared radiation ability touches the object. The principle of back-reflection generates corresponding infrared images based on the received reflected infrared radiation energy, which can achieve more accurate capture and improve the accuracy of welding quality detection.

Step A202: Use the maximum volume of the solder ball as the solder usage volume, and use the volume of the solder ball outside the through hole corresponding to the target solder point as the solder overflow volume.

Specifically, before the solder ball falls into the through hole of the target solder point, the largest solder ball volume is used as the solder volume V _a ; after the solder ball falls into the through hole of the target solder point, the process of filling the through hole , when the volume of solder outside the through hole continues to decrease, the volume when it is reduced to the minimum is regarded as the solder overflow volume V _b . Calculate (V _a -V _b ), which is the actual filling volume of solder in the through hole of the target solder joint, that is, the solder filling volume, and then divide the solder filling volume (V _a -V _b ) by the pre-entered target filling volume Get the fill percentage of the target solder joint/> Then multiply the filling percentage by the thickness of the PCBA motherboard, that is, the through hole height T, to get the value of the filling height/> Then compare the filling height with the target filling height. If the filling height is greater than or equal to the target filling height, it is judged that the welding quality of the target solder joint corresponding to the filling height is qualified. If the filling height is less than the target filling height, it is judged that the filling height corresponds to The welding quality of the target solder joint is unqualified, where T represents the thickness of the PCBA motherboard, that is, the height of the target solder joint through hole,/> Indicates the through hole diameter of the target solder joint,/> Indicates the diameter of the leg of the soldered part. Since after the through hole is welded into the leg of the part, the remaining volume is a hollow cylinder. By calculating the surface area of the through hole and subtracting the surface area of the pin, the bottom surface area of the hollow cylinder is obtained, and then the hollow cylinder is The bottom surface area is multiplied by the height of the hollow cylinder, that is, the thickness T of the PCBA motherboard, to obtain the volume of the hollow cylinder, which is the target filling volume.

Further, when the filling height is less than the target filling height, the welding quality of the target solder joint is judged to be unqualified.

Furthermore, when the filling height is less than the target filling height, the step of determining that the welding quality of the target solder joint is unqualified may include:

When the filling height is less than the target filling height, the target soldering point corresponding to the filling height is welded again. If the filling height of the target soldering point after re-welding is still less than the target filling height, the position of the target soldering point is recorded, and finally the position of the target soldering point is judged. The welding quality of the target solder joint is unqualified.

In this embodiment, through the above solution, a camera is specifically used to monitor the volume change of the solder ball formed during the contact between the solder corresponding to the target solder point and the soldering head, and the maximum volume of the solder ball is used as the solder usage volume. The volume of the solder ball outside the through hole corresponding to the target solder point is used as the solder overflow volume to realize real-time dynamic capture of the target solder joint with a long welding time, and through the infrared temperature sensing function of the camera, the captured area is The volume area is obtained to obtain more accurate volume capture, thereby improving the accuracy of welding quality detection.

Referring to Figure 5, Figure 5 is a schematic flow chart of another exemplary embodiment of the welding quality detection method of the present application. Step S1001, the step of obtaining the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point includes:

Step B100, obtain the welding time of the target solder joint;

This embodiment explains the method of obtaining the solder usage volume using the static method.

Specifically, the welding time refers to the time for welding the target solder joint, and the length of time is selected according to the thickness, material, etc. of the solder. According to the different welding times of different products, different methods are used to obtain the solder volume of different products. For example, products with a longer welding time usually use a larger solder volume, while products with a shorter welding time usually focus on the welding volume. Accuracy: According to the different welding times of different products, different acquisition methods are used for the solder volume of different products, thereby improving the acquisition efficiency and thus improving the detection efficiency of solder joint quality.

Step B200, if the target welding time is less than or equal to the preset welding time threshold, perform the steps of: obtaining the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point, and based on the solder usage volume and the solder overflow volume to calculate the solder filling volume.

Specifically, when the welding time of product B is less than or equal to the preset welding time threshold, the solder usage volume and solder overflow volume of product B are obtained using the static method, that is, after the welding of the target solder joint is completed, the tin delivery pipe is calculated The reduced volume of the tin wire is used as the solder volume, and the solder volume outside the through hole of the target solder joint after welding is used as the solder overflow volume.

This embodiment adopts the above solution, specifically by obtaining the welding time of the target solder point. If the target welding time is less than or equal to the preset welding time threshold, then perform the steps of: obtaining the solder usage volume of the target solder point, and the The solder overflow volume corresponding to the target solder joint, and based on the solder usage volume and solder overflow volume, the solder filling volume is calculated. For different products corresponding to different welding times, different actual filling volume calculation methods are used, because the welding time is longer Electronic products are more inclined to ensure the amount of tin used, and electronic products with shorter welding time are more inclined to the accuracy of welding. According to these different points, different calculation methods are used for the actual filling volume, which improves the calculation efficiency and thus improves the welding quality. detection efficiency.

Referring to Figure 6, Figure 6 is a schematic flow chart of another exemplary embodiment of the welding quality detection method of the present application. Step S1001, the steps of obtaining the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point include:

This embodiment further explains the static method in the embodiment corresponding to FIG. 5 .

Step B201: Obtain the cross-sectional area of the solder corresponding to the solder joint and the usage length of the solder, and calculate the current solder usage volume based on the cross-sectional area and the usage length;

Specifically, the static method means that after the welding of the target solder joint is completed, the reduced volume of the tin wire in the tin feeding pipe is calculated as the solder usage volume, and the solder volume outside the through hole of the target solder joint after welding is used as the solder overflow volume. . More specifically, let's take tin wire as the solder. Tin wire is usually a cylinder. The solder volume of the tin wire is calculated through the cylinder volume formula. The specific calculation formula is: Among them, v represents the tin feeding speed, t represents the tin feeding time,/> Indicates the tin wire diameter and obtains the current solder usage volume.

Step B202: After the target solder point is welded, the solder overflow volume corresponding to the target solder point is obtained.

Specifically, after the target solder point is welded, an industrial camera is used to obtain the volume of the tin overflow outside the through hole corresponding to the target solder point as the solder overflow volume. Since the static method is applicable to products, during welding, the focus is on welding. Accuracy, the solder usage volume is smaller than the products applicable to the dynamic method, and usually no overflow will occur. Therefore, in this embodiment, the solder overflow volume is 0 for explanation. When the solder overflow volume is welded on the products applicable to the static method, The pixel area of the overflow volume can also be captured by an industrial camera and combined with a visual algorithm to obtain the value of the solder overflow volume. Obtain solder usage volume through static method Then, divide the solder usage volume by the pre-entered target fill volume/> Get the fill percentage of the target solder joint/> Then multiply the filling percentage by the thickness of the PCBA motherboard, that is, the through hole height T, to get the value of the filling height/> Then compare the filling height with the target filling height. If the filling height is greater than or equal to the target filling height, it is judged that the welding quality of the target solder joint corresponding to the filling height is qualified. If the filling height is less than the target filling height, it is judged that the filling height corresponds to The welding quality of the target solder joint is unqualified, where T represents the thickness of the PCBA motherboard, that is, the height of the target solder joint through hole, Indicates the through hole diameter of the target solder joint,/> Indicates the diameter of the leg of the soldered part. Since after the through hole is welded into the leg of the part, the remaining volume is a hollow cylinder. By calculating the surface area of the through hole and subtracting the surface area of the pin, the bottom surface area of the hollow cylinder is obtained, and then the hollow cylinder is The bottom surface area is multiplied by the height of the hollow cylinder, that is, the thickness T of the PCBA motherboard, to obtain the volume of the hollow cylinder, which is the target filling volume.

In this embodiment, through the above solution, specifically by obtaining the cross-sectional area of the solder corresponding to the solder point and the usage length of the solder, and calculating the current solder usage volume based on the cross-sectional area and the usage length, After the target solder point is welded, the solder overflow volume corresponding to the target solder point is obtained, and the filling height is calculated based on the solder usage volume and the solder overflow volume. According to the filling height, the welding quality is detected, and the welding quality is detected through static This method uses different calculation methods for the solder volume of products with short welding time, which improves the efficiency of welding quality detection.

Referring to Figure 7, Figure 7 is a schematic flow chart of another exemplary embodiment of the welding quality detection method of the present application. Step S1001, based on the solder usage volume and the solder overflow volume, the steps of calculating the solder filling volume include:

Step C100, obtain the supplementary coefficient corresponding to the target solder joint;

Specifically, in Example 1, since different products have different sizes of through holes, for smaller through holes, the target filling height needs to be as high as possible, otherwise the solder joints corresponding to the through holes will be blocked. For larger through holes, the solder joints corresponding to the through holes will be blocked. For holes, the target filling height may not be equal to the thickness of the PCBA motherboard. Usually, when the solder in a large through hole is not fully filled, the corresponding solder joint can conduct normally. Therefore, different standards of target filling height are used for different through holes.

Step C200: Calculate the current filling height based on the solder filling volume, the target filling volume and the supplement coefficient, and determine the welding quality of the target solder joint based on the current filling height.

Specifically, the supplement coefficient k is used to correct the ratio of the solder filling volume, that is, the actual solder material in the through hole, to the pre-input target filling volume, that is, the remaining volume in the through hole after the through hole is soldered to the part foot, so that Factor to adjust fill height. Taking the dynamic method as an example to illustrate, when using the dynamic method, the calculation formula for the filling height is: When the filling height is lower than the target filling height, the volume of solder used is adjusted by multiplying the supplementing coefficient k, and then the filling height is adjusted. The adjusted filling height is If the adjusted filling height reaches the target filling height, the welding quality of the target solder joint is judged to be qualified, the supplementary coefficient k is recorded, and the supplementary coefficient k is used to adjust when welding the next through hole with the same diameter.

In this embodiment, through the above solution, specifically by obtaining the supplementary coefficient corresponding to the target solder point, based on the solder filling volume, the target filling volume and the supplementary coefficient, the current filling height is calculated, and based on the current The filling height determines the welding quality of the target solder joint, and adjusts the solder usage volume through the supplementary coefficient. Based on the adjusted solder usage volume and the target filling volume, the adjusted filling height tends to the target filling height, that is, the target solder joint. The welding quality tends to be qualified, which provides a method for users to adjust the welding quality judgment standards according to actual needs.

Referring to Figure 8, Figure 8 is a schematic flow chart of another exemplary embodiment of the welding quality detection method of the present application. Step S1001, based on the solder usage volume and the solder overflow volume, the steps of calculating the solder filling volume include:

Step D100, obtain the solder mass fraction corresponding to the target solder joint;

Specifically, taking tin-based solder as an example, the actual tin content of the tin-based solder in the shape of a tin wire will decrease due to factors such as aging or inadequate manufacturing processes. When the target solder joint corresponds to the In the hole, although the filling height reaches the target filling height, due to the decrease in the tin wire mass fraction, the actual tin content in the through hole does not reach the target tin content, which may cause the electrical characteristics of the target solder joint to be unstable. Therefore, , in actual testing, it is necessary to take the solder mass fraction w into consideration when calculating the solder volume corresponding to the product.

Step D200: Calculate the current solder filling volume based on the solder usage volume, the solder overflow volume and the solder mass fraction.

Specifically, the dynamic method is used as an example to illustrate. When using the dynamic method, the calculation formula of the solder filling volume is (V _a -V _b ). When the tin content in the through hole is lower than the target tin content, the through hole corresponds to If the solder joint is not conductive, the current solder filling volume is obtained by dividing the solder filling volume by the tin wire mass fraction w. The calculation formula is ((V _a -V _b )/w), and then based on the current solder filling volume welding.

This embodiment adopts the above solution, specifically by obtaining the solder mass fraction corresponding to the target solder joint, calculating the solder filling volume based on the solder usage volume, the solder overflow volume and the solder mass fraction, and calculating the solder filling volume from the filler impurities. From the perspective that the filled target solder joints may not conduct normally, the tin content is used as one of the standards for detecting welding quality, providing a diversified judgment method for welding quality and ensuring the reliability of welding quality judgment.

An embodiment of the present invention provides a welding quality detection device. The welding quality detection device includes:

The acquisition module is used to obtain the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint, and calculate the solder filling volume based on the solder usage volume and the solder overflow volume;

A calculation module configured to determine the welding quality of the target solder joint based on the solder filling volume and the target filling volume.

For the principle and implementation process of detecting welding quality in this embodiment, please refer to the above embodiments and will not be described again here.

In addition, an embodiment of the present invention also proposes a terminal device. The terminal device includes a memory, a processor, and a welding quality detection program stored in the memory and executable on the processor. The welding quality detection program When the detection program is executed by the processor, the welding quality detection method as described in the above embodiment is implemented.

Since this welding quality inspection program uses all the technical solutions of all the foregoing embodiments when executed by the processor, it has at least all the beneficial effects brought by all the technical solutions of all the foregoing embodiments, which will not be described again here.

In addition, embodiments of the present invention also provide a computer-readable storage medium. The computer-readable storage medium stores a welding quality detection program. When the welding quality detection program is executed by a processor, the welding quality detection program is implemented as described in the above embodiments. Welding quality detection method described above.

Since the welding quality detection program uses all the technical solutions of all the foregoing embodiments when executed by the processor, it has at least all the beneficial effects brought by all the technical solutions of all the foregoing embodiments, which will not be described again here.

Compared with the existing technology, automated equipment cannot guarantee the welding quality by controlling the welding time. There may be bad solder joints with less solder. Such bad solder joints are not easy to be found during manual visual inspection and can only be detected through It can be discovered by disassembling the whole machine, taking out the PCBA motherboard, and placing the motherboard on an X-Ray machine for inspection. However, the X-Ray machine itself is expensive and difficult for small and medium-sized processing plants to afford. Secondly, if X-Ray is used for every complete machine inspection, high inspection costs will be incurred. Therefore, X-Ray is only suitable for sampling inspection, and is generally used in industries. The sampling frequency is 1%, thus resulting in a sample that is not highly representative. The invention of this application is based on automatic spot welding equipment and combined with industrial vision, and designs a method that is compatible with welding and detection operations at the same time. Through this application, the automatic spot welding equipment can effectively judge the welding quality. X-Ray ray machines greatly reduce costs and can achieve high coverage. Compared with X-Ray ray machines, the operation is simpler, safer and faster.

It should be noted that, as used herein, the terms "include", "comprising" or any other variation thereof are intended to cover a non-exclusive inclusion, such that a process, method, article or system that includes a list of elements not only includes those elements, but It also includes other elements not expressly listed or that are inherent to the process, method, article or system. Without further limitation, an element defined by the statement "comprises a..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

The above serial numbers of the embodiments of the present invention are only for description and do not represent the advantages and disadvantages of the embodiments.

Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus the necessary general hardware platform. Of course, it can also be implemented by hardware, but in many cases the former is better. implementation. Based on this understanding, the technical solution of the present invention can be embodied in the form of a software product in essence or that contributes to the existing technology. The computer software product is stored in one of the above storage media (such as ROM/RAM, magnetic disc, optical disk), including several instructions to cause a terminal device (which can be a mobile phone, a computer, a server, a controlled terminal, or a network device, etc.) to execute the method of each embodiment of the present invention.

The above are only preferred embodiments of the present invention, and do not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the description and drawings of the present invention may be directly or indirectly used in other related technical fields. , are all similarly included in the scope of patent protection of the present invention.

Claims (10)

1. A method for detecting welding quality, characterized in that the method for detecting welding quality includes the following steps: Obtain the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint, and calculate the solder filling volume based on the solder usage volume and the solder overflow volume; Based on the solder filling volume and the target filling volume, determine the welding quality of the target solder joint; Wherein, judging the welding quality of the target solder joint based on the solder filling volume and the target filling volume includes: dividing the solder filling volume by the target filling volume to obtain a percentage; dividing the proportion The percentage is multiplied by the through hole height to obtain the filling height; the filling height is compared with the target filling height. If the filling height is less than the target filling height, the detection result of the welding quality is determined to be unqualified. If the filling height is If the filling height is greater than or equal to the target filling height, the detection result of the welding quality is determined to be qualified. When the filling height is greater than the target filling height, the greater part cannot exceed the preset range. 2. The method for detecting welding quality according to claim 1, wherein the step of obtaining the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint further includes: Obtain the welding time of the target solder joint; If the target welding time is greater than the preset welding time threshold, then perform the steps of: obtaining the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point, and based on the solder usage volume and the solder overflow volume, Calculate solder fill volume. 3. The method for detecting welding quality according to claim 2, wherein the step of obtaining the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint includes: Use a camera to monitor the volume change of the solder ball formed during the contact between the solder corresponding to the target solder joint and the soldering head; The maximum volume of the solder ball is used as the solder usage volume, and the volume of the solder ball outside the through hole corresponding to the target solder point is used as the solder overflow volume. 4. The method for detecting welding quality according to claim 1, wherein the step of obtaining the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint further includes: Obtain the welding time of the target solder joint; If the target welding time is less than or equal to the preset welding time threshold, then perform the steps of: obtaining the solder usage volume of the target solder point and the solder overflow volume corresponding to the target solder point, and based on the solder usage volume and solder overflow Volume, calculate the solder fill volume. 5. The method for detecting welding quality according to claim 4, wherein the step of obtaining the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint includes: Obtain the cross-sectional area of the solder corresponding to the solder joint and the usage length of the solder, and calculate the current solder usage volume based on the cross-sectional area and the usage length; After the target solder point is welded, the solder overflow volume corresponding to the target solder point is obtained. 6. The method for detecting welding quality according to claim 1, wherein the step of judging the welding quality of the target solder joint based on the solder filling volume and the target filling volume further includes: Obtain the supplementary coefficient corresponding to the target solder joint; The step of judging the welding quality of the target solder joint based on the solder filling volume and the target filling volume includes: Based on the solder filling volume corresponding to the target solder joint, the target filling volume and the supplement coefficient, the current filling height is calculated, and based on the current filling height, the welding quality of the target solder joint is judged. 7. The method for detecting welding quality according to claim 1, wherein the step of calculating the solder filling volume based on the solder usage volume and the solder overflow volume includes: Obtain the solder quality fraction corresponding to the target solder joint; Based on the solder usage volume, the solder overflow volume and the solder mass fraction, the current solder filling volume is calculated. 8. A device for detecting welding quality, characterized in that the device for detecting welding quality includes: The acquisition module is used to obtain the solder usage volume of the target solder joint and the solder overflow volume corresponding to the target solder joint, and calculate the solder filling volume based on the solder usage volume and the solder overflow volume; A calculation module configured to determine the welding quality of the target solder joint based on the solder filling volume and the target filling volume; wherein the welding quality of the target solder joint is judged based on the solder filling volume and the target filling volume. The method includes: dividing the solder filling volume by the target filling volume to obtain a percentage; multiplying the percentage and the through hole height to obtain a filling height; comparing the filling height with the target filling height, If the filling height is less than the target filling height, the detection result of the welding quality is determined to be unqualified; if the filling height is greater than or equal to the target filling height, the detection result of the welding quality is determined to be qualified, where, When the filling height is greater than the target filling height, the greater part cannot exceed the preset range. 9. A terminal device, characterized in that the terminal device includes a memory, a processor, and a welding quality detection program stored on the memory and executable on the processor, and the welding quality detection program When executed by the processor, the steps of the method according to any one of claims 1-7 are implemented. 10. A computer-readable storage medium, characterized in that a welding quality detection program is stored on the computer-readable storage medium, and when the welding quality detection program is executed by a processor, the welding quality detection program is implemented as claimed in claims 1-7 The steps of any of the methods described.