Welding quality real-time monitoring system, welding system and electric resistance welding method

Abstract

The invention provides a welding quality real-time monitoring system, a welding system and a resistance welding method. The welding quality real-time monitoring system comprises a data acquisition module, a waveform processing module, a real-time comparison module and a judgment alarm module. The data acquisition module is used for acquiring process parameters of multiple stages in the welding process in real time, and the process parameters at least comprise current, resistance, energy and pressure; the waveform processing module is used for processing the collected process parameters into a continuous real-time welding waveform curve; the real-time comparison module is used for comparing the real-time welding waveform curve with a preset standard waveform curve in real time; and the judgment and alarm module is used for generating and sending prompt or alarm information when any stage in the real-time welding waveform curve exceeds the corresponding qualified range. The system can monitor data in the welding process in real time and analyze the monitored data in real time, so that transient abnormity during welding is effectively obtained, and the welding quality of a product can be controlled.

Description

Technical Field

[0001] This invention relates to the field of welding equipment technology, and in particular to a real-time welding quality monitoring system, a welding system, and a resistance welding method. Background Technology

[0002] Welding technology, as a key process in modern manufacturing, is widely used in high-precision industrial fields such as automotive batteries, steel rails, aerospace, and energy equipment. Welding quality directly affects the safety, reliability, and service life of products. Traditional welding quality monitoring relies heavily on manual experience and post-production sampling, which suffers from poor real-time performance, discontinuous data, and delayed defect detection, making it difficult to achieve refined management of the entire welding process.

[0003] In existing technologies, some welding monitoring systems can collect basic parameters such as current, voltage, and pressure during the welding process, but they lack real-time analysis and intelligent criteria for welding waveforms, and cannot effectively warn of transient anomalies during the welding process.

[0004] Therefore, existing welding monitoring systems need to be improved to overcome the shortcomings of existing technologies. Summary of the Invention

[0005] To overcome the problems existing in related technologies, one of the objectives of this invention is to provide a real-time welding quality monitoring system. This system can monitor data during the welding process in real time and analyze the monitored data in real time, thereby effectively obtaining transient anomalies during welding, which helps to control the welding quality of products.

[0006] A real-time welding quality monitoring system, comprising: The data acquisition module is used to acquire process parameters at multiple stages of the welding process in real time. The process parameters include at least current, resistance, energy and pressure. The waveform processing module is used to process the acquired process parameters into continuous real-time welding waveform curves. The real-time comparison module is used to compare the real-time welding waveform curve with the preset standard waveform curve in real time. The alarm detection module is used to generate and issue prompts or alarm messages when any stage in the real-time welding waveform curve exceeds the corresponding qualified range.

[0007] In a preferred embodiment of the present invention, a standard waveform library is also included for storing preset standard waveform curves; The standard waveform curve includes waveform ranges for different welding stages. For example, it includes waveform ranges for the preheating stage, pre-welding stage, and welding stage of the welding process.

[0008] In a preferred embodiment of the present invention, the alarm determination module further includes: During different welding stages, if the process parameters in the current time unit differ from those in the previous time unit by only a set threshold, a prompt or alarm message is generated and issued. In this application, the current time unit and the previous time unit can be the current millisecond and the previous millisecond, that is, the time unit can be milliseconds.

[0009] In a preferred embodiment of the present invention, the welding process includes at least a preheating stage, a pre-welding stage, and a welding stage. The acceptable range for any stage of the standard waveform curve is set independently for different stages.

[0010] In a preferred embodiment of the present invention, a visual interactive interface is also included; The visual interactive interface is used for: The real-time welding waveform curve and the standard waveform curve are dynamically displayed in waveform diagram format. Different colors are used to visually distinguish between qualified and out-of-limit waveform segments; Upon receiving a user instruction, the selected historical welding waveform is set as a new standard waveform and stored in the standard waveform library.

[0011] In a preferred embodiment of the present invention, a data association structure is provided, which is used to obtain the identifier of the workpiece during welding and bind the welding data of the welding process to the workpiece. The welding data includes at least: welding process parameter waveforms, equipment number and program number used, quality judgment results, and timestamps; The data association structure also includes a memory for storing welding data after the pre-workpiece is bonded.

[0012] In a preferred embodiment of the present invention, all welding data stored in the memory is obtained; Welding data were analyzed to obtain the standard deviation and drift trend of process parameters; If the standard deviation and drift trend of the process parameters exceed the preset threshold, an equipment maintenance prompt will be issued.

[0013] A second objective of this invention is to provide a welding system, including a body and a control system, wherein the control system is used to implement the welding quality real-time monitoring system as described above.

[0014] A third objective of this invention is to provide a resistance welding method, implemented based on the welding system described above.

[0015] The beneficial effects of this invention are as follows: This invention provides a real-time welding quality monitoring system, comprising a data acquisition module, a waveform processing module, a real-time comparison module, and a judgment and alarm module. The data acquisition module collects process parameters at multiple stages during the welding process in real time, including at least current, resistance, energy, and pressure. The waveform processing module processes the collected process parameters into continuous real-time welding waveform curves. The real-time comparison module compares the real-time welding waveform curves with preset standard waveform curves in real time. The judgment and alarm module generates and issues prompts or alarm messages when any stage of the real-time welding waveform curve exceeds the corresponding acceptable range. Through real-time comparison of the entire waveform and the entire process, this system can accurately capture transient anomalies (such as instantaneous current spikes or instantaneous pressure drops) that are extremely short in duration but highly dangerous, thus refining the granularity of quality monitoring from "a single weld point" to "every millisecond within a weld point." Furthermore, by setting independent acceptable ranges for different welding stages, the system can identify the specific process step where the anomaly occurs. This avoids the limitations of a single threshold criterion, making quality judgment more scientific and accurate, while eliminating the problem of inconsistent judgment standards caused by differences in personnel experience.

[0016] This application also provides a welding system including the above-mentioned real-time welding quality monitoring system and a resistance welding method based on the welding system. The welding system can improve the welding quality of the workpiece and ensure product yield. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the real-time welding quality monitoring system provided in an embodiment of the present invention; Figure 2 This is a flowchart of the method based on the above-described real-time welding quality monitoring system embodiment provided in the embodiments of the present invention; Figure 3 These are schematic diagrams illustrating different stages of the welding process provided in embodiments of the present invention; Figure 4 This is a schematic diagram illustrating resistance monitoring at different stages of the welding process provided in an embodiment of the present invention; Figure 5 This is a schematic diagram illustrating the monitoring of current at different stages of the welding process provided in an embodiment of the present invention.

[0018] Figure label: 1. Data acquisition module; 2. Waveform processing module; 3. Real-time comparison module; 4. Judgment and alarm module; 5. Visual interactive interface; 6. Data association structure. Detailed Implementation

[0019] Preferred embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While preferred embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0020] Welding technology, as a key process in modern manufacturing, is widely used in high-precision industrial fields such as automotive batteries, steel rails, aerospace, and energy equipment. Welding quality directly affects the safety, reliability, and service life of products. Traditional welding quality monitoring relies heavily on manual experience and post-production sampling, which suffers from poor real-time performance, discontinuous data, and delayed defect detection, making it difficult to achieve refined management of the entire welding process.

[0021] In existing technologies, some welding monitoring systems can collect basic parameters such as current, voltage, and pressure during the welding process, but they lack real-time analysis and intelligent criteria for welding waveforms, and cannot effectively warn of transient anomalies during the welding process.

[0022] Based on this, this application provides a real-time welding quality monitoring system.

[0023] Example 1 like Figures 1-5 As shown in the figure, this embodiment provides a real-time welding quality monitoring system, including: Data acquisition module 1 is used to acquire process parameters at multiple stages of the welding process in real time. The process parameters include at least current, resistance, energy and pressure. Waveform processing module 2 is used to process the acquired process parameters into continuous real-time welding waveform curves; Real-time comparison module 3 is used to compare the real-time welding waveform curve with the preset standard waveform curve in real time; The alarm module 4 is used to generate and issue prompts or alarm information when any stage in the real-time welding waveform curve exceeds the corresponding qualified range.

[0024] Specifically, data acquisition module 1 collects process parameters in real time for the three core stages of the welding process: preheating, pre-welding, and welding, with an acquisition frequency of no less than 1kHz (ensuring millisecond-level data accuracy). Data acquisition parameters should include at least welding current (A), welding resistance (Ω), input energy (J, calculated from current, voltage, and time), and welding pressure (N). The parameter acquisition error should be ≤ ±0.5%. Furthermore, the analog signal is converted into a digital signal and transmitted to the waveform processing module 2 via a current sensor, resistance detection unit, pressure sensor and energy calculation chip connected in series in the welding circuit.

[0025] Waveform processing module 2 is directly coupled to data acquisition module 1. It receives discrete data streams from data acquisition module 1 and, through data smoothing and interpolation algorithms, processes and synthesizes the discrete process parameter data points into a continuous, time-axis-aligned real-time welding waveform curve. This curve fully demonstrates the dynamic changes of each parameter throughout the entire welding cycle.

[0026] The real-time comparison module 3 has a pre-stored library of standard waveform curves. These standard waveform curves are ideal process curves derived from statistical summarization of a large amount of qualified weld point data. Furthermore, corresponding acceptable ranges (usually represented as tolerance bands formed by a certain percentage fluctuation above and below the standard curve) are independently set for different stages such as the preheating stage, pre-welding stage, and welding stage. During the welding process, this module obtains the latest real-time welding waveform curve from the waveform processing module 2 in real time and compares it with the corresponding standard waveform curve point by point and stage by stage.

[0027] The alarm judgment module 4 is connected to the output of the real-time comparison module 3. Based on the result of the real-time comparison module 3, it executes strict pass / fail judgment logic: once it detects that the real-time welding waveform curve exceeds the preset pass / fail range for any stage (e.g., the current value of the pre-welding section, the resistance value of the welding section) at any point, an alarm message is immediately generated. This alarm message is displayed as a red flashing indicator on the system interface, an audible alarm, or a notification sent to the manager's mobile terminal via the integrated industrial IoT platform.

[0028] See Figure 4 , Figure 4 A schematic diagram showing the change of the monitored resistance over time is provided, in which... Figure 4 The shaded area in the diagram represents the reasonable range of resistance. When the monitored real-time resistance value exceeds the upper or lower limit of the shaded area, the monitoring system generates and issues a prompt or alarm message.

[0029] When the system is in operation, the operator selects the appropriate welding program and starts the task on the host computer software. The system then begins operation: S100, Data Acquisition Module 1 continuously captures raw parameters; S100 and waveform processing module 2 combine them into a continuous waveform; S300, Real-time Comparison Module 3 compares the real-time waveform being formed with the standard waveform in real time; S400, the alarm module 4 will sound an alarm immediately when any "out-of-bounds" behavior is detected.

[0030] Furthermore, it also includes a standard waveform library for storing preset standard waveform curves; The standard waveform curve includes waveform ranges for different welding stages (preheating stage, pre-welding stage, welding stage).

[0031] Furthermore, the alarm determination module 4 also includes: During different welding stages, if the process parameters in the current time unit differ from those in the previous time unit (e.g., between the previous millisecond and the next millisecond) by only a difference exceeding a set threshold, a prompt or alarm message is generated and issued. During welding, there may be extremely brief but highly dangerous anomalies, such as instantaneous spikes, drops, or oscillations caused by power grid disturbances, electromagnetic interference, or mechanical transmission jamming. These anomalies are extremely short-lived and may be averaged out in overall energy or average value calculations, making them undetectable by criteria based on the overall stage range. However, the resulting microstructural defects (such as incomplete welds or overheating) are real. This application, by analyzing historical data and trends of abrupt alarms, allows maintenance personnel to detect potential faults in equipment before batch quality incidents occur; for example, the response speed of a solenoid valve is slowing down. This achieves an upgrade from "reactive maintenance" to "predictive maintenance," reducing unplanned downtime and avoiding more serious equipment damage and production losses.

[0032] By setting independent acceptable ranges for different stages such as preheating, pre-welding, and welding, the specific process step where the abnormality occurred can be located immediately.

[0033] For example, when the system alarms and displays "Pre-welding current exceeds limit," process engineers can directly focus on checking parameter settings related to the pre-welding current, electrode tip condition, or material surface cleanliness. If it's "Insufficient welding energy," the main circuit power supply or welding time can be checked. This greatly shortens troubleshooting time, transforming problem diagnosis from "finding a needle in a haystack" to "precise navigation," significantly improving production and maintenance efficiency.

[0034] Different welding stages have their unique physical processes and parameter characteristics. A uniform, broad tolerance range may miss minor anomalies in some stages or misjudge normal fluctuations in others as abnormal. This application allows for independent adjustment of the process characteristics of each stage, enabling stricter tolerances for stages with high stability requirements and more reasonable tolerances for stages with drastic dynamic changes. This design makes quality judgment more scientific and reasonable, ensuring detection sensitivity while reducing false alarm rates and improving system reliability and trustworthiness.

[0035] Furthermore, the welding process includes at least a preheating stage, a pre-welding stage, and a welding stage. The acceptable range for any stage of the standard waveform curve is set independently for different stages.

[0036] Furthermore, it also includes a visual interactive interface 5; The visual interactive interface 5 is used for: The real-time welding waveform curve and the standard waveform curve are dynamically displayed in waveform diagram format. Different colors are used to visually distinguish between qualified and out-of-limit waveform segments; Upon receiving a user instruction, the selected historical welding waveform is set as a new standard waveform and stored in the standard waveform library.

[0037] Furthermore, the data association structure 6 is used to obtain the identifier of the workpiece during welding and bind the welding data of the welding process to the workpiece; The welding data includes at least: welding process parameter waveforms, equipment number and program number used, quality judgment results, and timestamps; The data association structure 6 also includes a memory for storing welding data after the pre-workpiece is bonded.

[0038] Furthermore, retrieve all the welding data stored in the memory; Welding data were analyzed to obtain the standard deviation and drift trend of process parameters; If the standard deviation and drift trend of the process parameters exceed the preset threshold, an equipment maintenance prompt will be issued.

[0039] Example 2 This embodiment provides a welding system, including a body and a control system, wherein the control system includes the welding quality real-time monitoring system described above.

[0040] This control system is the brain of the welding system, integrating the real-time welding quality monitoring system described in the preceding embodiments as a core functional unit. This means that the hardware (such as an industrial computer or PLC) and software of the control system contain all the necessary components and programs to achieve functions such as data acquisition, waveform processing, real-time comparison, alarm judgment, data association, and storage.

[0041] During operation, the operator selects the welding program on the control system's interactive interface and places the workpiece with a unique identifier (such as a QR code) at the welding station. The barcode scanner automatically reads the workpiece identifier.

[0042] Welding Execution and Data Acquisition: The operator initiates welding. The welding power source, pressure mechanism, and other components within the machine begin operating, executing the welding sequence. Simultaneously, the data acquisition module 1 in the control system collects process parameters such as current and pressure in real time through sensors on the machine body.

[0043] Real-time quality monitoring and feedback: The collected data is sent to the waveform processing module and the real-time comparison module for comparison with preset standard waveforms. The judgment and alarm module makes millisecond-level judgments based on the comparison results.

[0044] Closed-loop control is tied to results: Once a defect is determined to be non-compliant, the system can immediately issue an instruction to the machine to interrupt the current welding process or mark the workpiece as non-compliant to prevent the defect from flowing into the next process.

[0045] Regardless of whether the weld is qualified or not, all the data from this welding process, including real-time waveforms, equipment number, program number, quality judgment results, and timestamps, will be bound to the workpiece identifier read at the beginning through a data association structure and stored in the database.

[0046] Example 3 This embodiment provides a resistance welding method, implemented based on the welding system described above.

[0047] The method is as follows: The workpiece to be welded is clamped into the welding system's workstation. A unique identifier (such as a part identification card or QR code) is obtained from the workpiece using a barcode scanner integrated into the system. The welding program corresponding to that workpiece is selected or invoked in the control system. The system establishes an association between the workpiece identifier and the current welding task.

[0048] The operator initiates the welding cycle. The welding system begins executing the welding sequence (typically including: pressurization → preheating → pre-welding → welding → holding → rest). Simultaneously, the system's data acquisition module 1 is automatically activated and begins real-time acquisition of process parameters for each stage of the welding process at high frequency (e.g., ≥1kHz), including at least current, resistance, energy, and pressure.

[0049] The waveform processing module synthesizes the collected discrete parameter data into a continuous real-time welding waveform curve. The real-time comparison module synchronously compares the emerging real-time welding waveform curve with the corresponding standard waveform curve retrieved from the standard waveform library. The standard waveform curve has independent acceptable ranges for the preheating section, pre-welding section, and welding section.

[0050] The alarm detection module makes a judgment based on the comparison results: a) If the real-time waveform exceeds the acceptable range for any stage, an alarm message will be generated immediately.

[0051] b) Simultaneously, millisecond-level transient anomaly detection is performed. If the parameter difference between adjacent milliseconds exceeds the set threshold, an alarm is immediately triggered.

[0052] Based on the judgment result, the system executes closed-loop control: If a serious non-compliance is determined, an instruction can be sent to the welding system to immediately interrupt the welding process, preventing waste of resources and damage to equipment.

[0053] Regardless of whether the system is interrupted, the system interface will issue an audible and visual alarm to remind the operator.

[0054] After the welding task is completed, the system automatically binds the entire welding process data with the workpiece identifier obtained from the barcode scanner. The entire process data includes: complete process parameter waveforms, equipment number, program number, quality judgment results, alarm records, and timestamps.

[0055] The bound data packets are stored in the memory to form a traceable production record.

[0056] The system periodically analyzes the historical welding data of a certain device in the memory and calculates the standard deviation and drift trend of key process parameters (such as welding energy and peak current).

[0057] When the analysis results indicate that the stability or accuracy of the parameters continues to deteriorate and exceeds the preset threshold, the system automatically sends equipment maintenance prompts to maintenance personnel to achieve predictive maintenance.

[0058] This method transforms the previously experience-dependent, "black box" welding process into a transparent, data-driven, measurable, and analyzable process. The quality of each weld point is supported by objective, quantifiable data, laying a solid foundation for process standardization and quality control. Furthermore, this method shifts quality inspection from "after-the-fact" to "during-the-process," and can immediately prevent defects from occurring by interrupting welding. This not only saves raw materials and energy but also prevents defective parts from flowing into subsequent, higher-value assembly stages, significantly reducing overall quality costs.

[0059] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings. In the description of this application, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0060] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways, and the spatial relative descriptions used herein will be interpreted accordingly.

[0061] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, these terms have no special meaning and therefore should not be construed as limiting the scope of protection of this application. The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A real-time welding quality monitoring system, characterized in that, include: The data acquisition module is used to acquire process parameters at multiple stages of the welding process in real time. The process parameters include at least current, resistance, energy and pressure. The waveform processing module is used to process the acquired process parameters into continuous real-time welding waveform curves. The real-time comparison module is used to compare the real-time welding waveform curve with the preset standard waveform curve in real time. The alarm detection module is used to generate and issue prompts or alarm messages when any stage in the real-time welding waveform curve exceeds the corresponding qualified range.

2. The real-time welding quality monitoring system according to claim 1, characterized in that: It also includes a standard waveform library for storing preset standard waveform curves; The standard waveform curve includes waveform ranges for different welding stages.

3. The real-time welding quality monitoring system according to claim 2, characterized in that: The alarm determination module also includes: At different welding stages, if the process parameters in the current time unit differ from those in the previous time unit by more than a set threshold, a prompt or alarm message will be generated and issued.

4. The real-time welding quality monitoring system according to claim 2, characterized in that: The welding process includes multiple stages, including at least a preheating stage, a pre-welding stage, and a welding stage; The acceptable range for any stage of the standard waveform curve is set independently for different stages.

5. The real-time welding quality monitoring system according to any one of claims 1-4, characterized in that: It also includes a visual interactive interface; The visual interactive interface is used for: The real-time welding waveform curve and the standard waveform curve are dynamically displayed in waveform diagram format. Different colors are used to visually distinguish between qualified and out-of-limit waveform segments; Upon receiving a user instruction, the selected historical welding waveform is set as a new standard waveform and stored in the standard waveform library.

6. The real-time welding quality monitoring system according to any one of claims 1-4, characterized in that: A data association structure is used to obtain the identifier of the workpiece during welding and bind the welding data of the welding process to the workpiece. The welding data includes at least: welding process parameter waveforms, equipment number and program number used, quality judgment results, and timestamps; The data association structure also includes a memory for storing welding data after the pre-workpiece is bonded.

7. The real-time welding quality monitoring system according to claim 6, characterized in that: Also includes: Retrieve all welding data stored in the memory; Welding data were analyzed to obtain the standard deviation and drift trend of process parameters; If the standard deviation and drift trend of the process parameters exceed the preset threshold, an equipment maintenance prompt will be issued.

8. A welding system, comprising a body and a control system, characterized in that: The control system includes the welding quality real-time monitoring system as described in any one of claims 1-7.

9. A resistance welding method, characterized in that: Implemented based on the welding system as described in claim 8.

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