Welding equipment and welding quality detection method

Abstract

The invention relates to welding equipment and a welding quality detection method. The welding equipment comprises a resistance spot welding machine and a control device of the resistance spot welding machine, a first electrode and a second electrode of the resistance spot welding machine are provided with an ultrasonic vibrator and an ultrasonic probe which are used for ultrasonic detection respectively and used for conducting ultrasonic detection on welding base metal located between the two electrodes, and ultrasonic detection signal output of the probe is connected into the control device. And the control system analyzes the ultrasonic detection signal to obtain an ultrasonic detection result. According to the welding quality detection method, real-time ultrasonic detection on a welding spot is carried out through the ultrasonic vibrator and the ultrasonic probe in the welding process, and the welding process and / or welding quality are / is analyzed according to ultrasonic detection data sent by the ultrasonic probe. According to the invention, ultrasonic self-detection and corresponding analysis can be implemented in the welding process.

Description

Technical Field

[0001] The invention relates to a self-detecting resistance spot welder with a self-detecting function, and also relates to a welding quality detection method based on the welding equipment. Background Art

[0002] Resistance spot welding, as a welding device, is the primary welding method used in automobile body manufacturing. Automotive manufacturing quality is closely linked to safety issues, particularly the quality of automobile body welding. However, resistance welding quality inspections currently rely on manual spot checks, which cannot guarantee 100% quality control. Quality issues such as porosity and cold welds cannot be detected promptly. Existing resistance welding machines can record welding parameters (current, voltage, and weld strength) in real time, storing welding process parameters and quality inspection data for traceability in automotive manufacturing. However, they cannot provide real-time quality monitoring of the welding process. The introduction of intelligent manufacturing systems in automotive manufacturing, in particular, requires highly efficient and reliable welding equipment and automated welding quality inspection equipment to improve welding quality, intelligently match welding parameters, automatically inspect welding quality, and reduce manual spot checks. Summary of the Invention

[0003] The purpose of the present invention is to enable welding equipment to perform ultrasonic self-detection during the welding process, so as to better ensure welding quality and save manpower.

[0004] The technical solution of the present invention is: welding equipment, including a resistance spot welder and a control device for the resistance spot welder, the resistance spot welder is provided with an electrode pair for resistance spot welding, the electrode pair is composed of a first electrode and a second electrode arranged opposite to each other, the first electrode and the second electrode are respectively provided with an ultrasonic vibrator and an ultrasonic probe for ultrasonic detection, which are used to perform ultrasonic detection on a welding base material (including a weld nugget) located between the two electrodes (the first electrode and the second electrode), the ultrasonic detection (scanning) signal output of the ultrasonic probe is connected to the control device, and the control system of the resistance spot welder (including the control device, and may or may not include a host computer and other supporting facilities) obtains an ultrasonic detection result based on the ultrasonic detection (scanning) signal analysis.

[0005] The end face of the first electrode (the end face opposite the second electrode, or the front face) and the end face of the second electrode (the end face opposite the first electrode, or the front face) serve as the electrode tip contact surfaces, intended for direct contact with the weld base metal. During use, the weld base metal is placed between the first and second electrodes, and the electrode drive mechanism (also known as the welding clamp tightening and movement mechanism, or pressure-applying mechanism) brings the electrode tip contact surfaces of the two electrodes into contact (pressure contact) with the weld base metal.

[0006] The positions of the first electrode and the second electrode can be flexibly set according to actual needs. The specific position setting should not hinder the welding action of the spot welder and ensure that ultrasonic testing can be effectively performed on the weld during the welding process (including the clamping and holding pressure stage).

[0007] Preferably, the spot welder is provided with a clamp-type mounting frame (or "clamp-type mounting frame"). The first electrode and the second electrode are mounted at opposite ends of the clamp-type mounting frame, respectively. At least one of the first electrode and the second electrode (the first electrode or the second electrode) is provided with an electrode drive mechanism, which is movably connected to the clamp-type mounting frame via the corresponding electrode drive mechanism. The electrode drive mechanism can thereby drive the corresponding electrode up and down, thereby changing the spacing between the two electrodes and clamping or loosening the base metal to be welded.

[0008] Preferably, the first electrode adopts a hollow structure (eg, a cylindrical / cup-shaped structure) and is provided with a cavity (cavity), and the ultrasonic vibrator is installed in the cavity of the first electrode.

[0009] Preferably, the second electrode adopts a hollow structure and is provided with a cavity (cavity), and the ultrasonic probe is installed in the cavity of the second electrode.

[0010] For example, both the first and second electrodes can be copper electrode caps (cup-shaped / cylindrical, open at the rear end and closed at the front end). The electrode caps can be positioned and installed according to existing techniques. If the end surface of the electrode cap that directly contacts the base metal during welding becomes worn, it can be reground using specialized tools. If wear is severe, the entire electrode cap can be replaced.

[0011] Preferably, a first elastic bracket (or elastic bracket, which acts as or mainly acts by elastic force with the supported / fixed part such as the ultrasonic vibrator or ultrasonic probe) is provided in the cavity of the first electrode for pressing and fixing the ultrasonic vibrator.

[0012] Preferably, a second elastic support for pressing and fixing the ultrasonic probe is provided in the cavity of the second electrode.

[0013] Preferably, the ultrasonic vibrator is located at the cavity axis position of the first electrode (the central position of the cavity cross section), and a gap is left between its circumference (side surface) and end surface and the corresponding cavity inner wall to form a first cooling medium channel. The first cooling medium channel is provided with a water inlet and a water outlet for connecting the input pipe and the output pipe of the cooling medium to achieve forced cooling.

[0014] Depending on the actual situation, the water inlet and outlet of the first cooling medium channel can be opened on the clamp-type fixing frame (or on the electrode driving mechanism) at the position connected to the rear end of the first electrode (the cup mouth end of the cup-shaped structure), connecting to the area (first cooling medium channel) at the corresponding end of the first electrode cavity that is not covered by the ultrasonic voltage vibrator, or opened on the side wall of the rear part of the first electrode, and the water inlet and outlet are symmetrically (mirror-symmetrical with respect to any longitudinal section of the cavity) arranged on both sides (on both sides of the symmetry plane).

[0015] A partition can be set between the circumferential surface of the ultrasonic vibrator and the inner wall of the cavity to divide the annular gap between the circumferential surface of the ultrasonic vibrator and the inner wall of the cavity into a water inlet channel connected to the water inlet and a water outlet channel connected to the water outlet. After the cooling medium (for example, cooling water or cooling oil) flows into the water inlet, it flows through the water inlet channel to the gap between the front end surface of the ultrasonic vibrator and the cavity, and then flows into the water outlet channel and flows out from the water outlet.

[0016] Preferably, the first elastic support is a water-permeable support, for example, formed by connecting a plurality of bent spring sheets, with gaps left between the spring sheets, through which the cooling medium can pass, thereby meeting the water-permeable requirement.

[0017] Preferably, the ultrasonic probe is a water immersion ultrasonic probe.

[0018] Preferably, the ultrasonic probe is located at the cavity axis position of the second electrode (the central position of the cavity cross section), and a gap is left between its circumference (side surface) and end surface and the corresponding cavity inner wall to form a second cooling medium channel. The second cooling medium channel is provided with a water inlet and a water outlet, which are used for the input and output pipes of the cooling medium to achieve forced cooling.

[0019] Depending on the actual situation, the water inlet and outlet of the second cooling medium channel can be opened on the clamp-type fixing frame (or on the electrode driving mechanism) at the position connected to the rear end of the second electrode (the cup mouth end of the cup-shaped structure), connecting the area of the corresponding end of the second electrode cavity that is not covered by the sensor (the second cooling medium channel), or opened on the side wall of the rear part of the second electrode, and the water inlet and outlet are symmetrically (mirror-symmetrically with respect to any longitudinal section of the cavity) arranged on both sides (on both sides of the symmetry plane). A partition can be set between the peripheral surface of the ultrasonic probe / ultrasonic sensor and the inner wall of the cavity to separate the annular gap between the peripheral surface of the ultrasonic probe / ultrasonic sensor and the inner wall of the cavity into an inlet channel connected to the water inlet and an outlet channel connected to the water outlet. After the cooling medium (for example, cooling water or cooling oil) flows into the water inlet, it flows through the water inlet channel to the gap between the front end face of the ultrasonic vibrator and the cavity, and then flows into the outlet channel and flows out from the outlet.

[0020] Preferably, the second elastic support is a water-permeable support, for example, formed by connecting a plurality of bent spring sheets, with gaps between the spring sheets, through which the cooling medium can pass, thereby meeting the water-permeable requirement.

[0021] Preferably, the output of the ultrasonic probe (eg, acoustic wave detection / scanning data output) is connected to a control device of the spot welder.

[0022] Preferably, the control device constitutes a welding control system (or called a spot welding machine control system), or the control device is connected to a host computer and together with the host computer constitutes a welding control system.

[0023] The control device is provided with a communication interface for connecting to a host computer and / or other devices, such as accessing a local area network.

[0024] The ultrasonic detection (scanning) information (data) from the ultrasonic probe can be analyzed and processed by the control device or the control device and the host computer to obtain the detection results, and the welding process (process parameters) can be adjusted and controlled according to the real-time detection results during the welding process to obtain better welding effects.

[0025] Preferably, the control device is connected to a host computer and together with the host computer constitutes a welding control system. When appropriate, the control device may be disconnected from the host computer and serve as a welding control system alone.

[0026] The host computer can send operation instructions to the execution terminal. The host computer can send relevant control instructions to each execution terminal through the internal bus, and the data of each execution terminal can be fed back to the host computer to maintain consistent working sequence.

[0027] Preferably, the control device is provided with an automatic control mode and a manual control mode.

[0028] Furthermore, both the control device and the host computer are provided with input devices (e.g., relevant buttons, a keyboard, a touch screen, and / or an interface or communication module capable of receiving relevant control instructions, etc.), through which data and / or instructions can be input. For example, the input device can be used to implement operating mode selection and switching.

[0029] In the automatic control mode, the control device controls the spot welding machine to operate according to the set automatic working mode (including timing), implements welding (each step) and quality inspection (including ultrasonic inspection data collection and transmission), and when receiving the control instructions issued by the host computer, it gives priority to executing the operation instructions of the host computer.

[0030] In manual control mode, the control device controls the operation of the spot welding machine according to the manually input operating instructions, and implements parameter setting, live testing, learning and teaching, quality judgment setting and intelligent learning based on manual input.

[0031] Preferably, the control device is provided with a remote control network interface, which is used for exchanging welding machine power supply parameters, work execution commands and external control data.

[0032] Furthermore, the control device constitutes a welding control system (or spot welding machine control system), or the control device is connected to a host computer and together with the host computer constitutes a welding control system.

[0033] The control device may be provided with a communication interface for connecting to a host computer and / or other equipment The control device may be provided with any part or all of the following: a welding basic parameter acquisition module, an ultrasonic excitation control module, an ultrasonic excitation synchronization module, a non-destructive testing data acquisition module, a non-destructive testing synchronization module, and a predictive quality analysis module. For example: The control device can be provided with a basic welding parameter acquisition module for collecting real-time welding process data (including process-related data). For example, current, voltage, clamping force, tightening time, welding temperature, ambient temperature and shift, etc. In particular, during the pre-reading welding process, the workpiece time point, preheating time start point, preheating time, welding start time point, welding time, post-weld pressure holding time point, pressure holding time and related information should be strengthened. Figure 1 Extraction and collection of welding machine control time nodes and timing.

[0034] The control device may be provided with an ultrasonic excitation control module for controlling the ultrasonic vibrator to generate acoustic vibration excitation. The ultrasonic excitation control module may be provided with an ultrasonic excitation generator control terminal connected to the ultrasonic vibrator, and the ultrasonic excitation generator control terminal is controlled by the ultrasonic excitation generator control terminal.

[0035] The control device may include an ultrasonic excitation synchronization module for controlling the synchronization of ultrasonic excitation and welding. For example, the ultrasonic excitation synchronization module may function as a switch to control whether ultrasonic excitation is active, connected to the ultrasonic vibrator, for example, by connecting to the ultrasonic vibrator's power supply circuit or power switch control circuit.

[0036] The ultrasonic excitation synchronization module has two control modes: synchronous welding machine current induction switch control and welding machine internal timing control.

[0037] The control device is provided with a non-destructive testing data acquisition module for acquiring ultrasonic testing data of the ultrasonic probe to obtain ultrasonic A-scan images (scan data) and C-scan images of the weld point.

[0038] The non-destructive testing data acquisition module has two data acquisition modes: full-time data acquisition and pressure-holding period data acquisition.

[0039] The control device is provided with a non-destructive testing synchronization module for implementing synchronous control of ultrasonic testing, welding and pressure maintenance.

[0040] The nondestructive testing synchronization module can be used as a switch to control whether nondestructive testing data collection is working, connected to the ultrasonic probe, for example, connected to the power circuit or startup control circuit of the ultrasonic probe.

[0041] The control device features a predictive quality analysis module, which performs predictive analysis and evaluation of welding quality based on real-time welding process data and ultrasonic testing data. This module can generate quality data curves based on actual needs, analyze weld quality control trends, and generate alarms when quality (quality evaluation indicators) exceed historical averages. Data processing and analysis can be performed with the support of relevant software.

[0042] The control device is provided with a storage and calculation module for storing welding (control) parameters, welding process data and ultrasonic detection data.

[0043] In the context of existing technologies, the above modules can use corresponding chips or other components / devices, or the data processor (data processing device) can be enabled with corresponding functions with the support of software. Welding quality can be determined based on non-destructive testing data images.

[0044] A welding quality detection method is provided, wherein resistance spot welding is performed using any of the welding devices disclosed in the present invention. During the welding process, real-time ultrasonic detection of the weld spot (weld parent material and the weld nugget formed) is performed using the ultrasonic vibrator and ultrasonic probe. The welding process and / or welding quality are analyzed based on the ultrasonic detection data sent by the ultrasonic probe.

[0045] Preferably, the ultrasonic detection data may be any one or more (including all) of A-scan data, B-scan data and / or C-scan data.

[0046] Preferably, the welding control system controls the spot welding machine in two modes: automatic control and manual control. In these two control modes, the spot welding machine can perform automatic welding or manual control welding respectively.

[0047] Preferably, the welding control system has an intelligent learning function and a learning and teaching function.

[0048] Preferably, the welding control system generates / outputs corresponding ultrasonic scanning images of the welding points according to ultrasonic detection data from the ultrasonic probe.

[0049] Preferably, the welding control system analyzes the quality control trend of the weld spot based on the ultrasonic detection data from the ultrasonic probe, and implements / issues an alarm prompt when the real-time quality analysis result exceeds the historical average value or the quality control threshold.

[0050] The beneficial effects of the present invention are as follows: due to the provision of an ultrasonic probe and an ultrasonic vibrator that match each other, ultrasonic waves are generated by the ultrasonic vibrator, and ultrasonic signals are collected by the ultrasonic probe, so that ultrasonic detection can be automatically carried out during the welding process and / or when welding is completed to obtain detection results, and the welding quality of all products can be obtained without the need for manual detection after welding; due to the ultrasonic vibration excitation effect generated by the ultrasonic vibrator during the welding process, it is beneficial to reduce welding pores and improve the welding quality of products; due to the provision of a cooling medium channel in the electrode, the forced cooling of the ultrasonic vibrator, ultrasonic probe and motor by connecting to a cooling medium circulation system is beneficial to ensuring the stability and service life of the work; due to the provision of a water-permeable bracket to The sonic vibrator and ultrasonic probe are pressed from the front end, which is conducive to ensuring stability under vibration conditions, and the water permeability of the bracket does not hinder the flow of the cooling medium; due to the provision of a control device and a host computer, automatic control and manual control can be realized, ultrasonic excitation and ultrasonic detection can be implemented, and better welding quality can be obtained through ultrasonic excitation. A-scan and C-scan images of the weld point can be obtained in real time through ultrasonic detection without hindering the welding process or consuming detection time. With the support of existing information technology, the welding quality can be evaluated, the welding quality trend can be analyzed, the welding process can be improved, and alarm prompts can be implemented when necessary; intelligent learning and learning teaching can be implemented with the support of existing information technology to continuously improve the welding quality under automatic control. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 is a schematic diagram of the present invention; Figure 2 This is a cross-sectional schematic diagram of the internal structure of the electrode and the clamp-type fixing frame according to the present invention; Figure 3 This is a cross-sectional schematic diagram of the cooling medium channel and the elastic water-permeable support according to the present invention; Figure 4 for Figure 3 AA view shown; Figure 5 is an architectural diagram of a control device that can be used in conjunction with the present invention; Figure 6 An ultrasonic excitation control logic diagram of a control device that can be used in conjunction with the present invention; Figure 7 A nondestructive testing control logic diagram of a control device that can be used in conjunction with the present invention; Figure 8 A quality intelligent evaluation learning logic diagram for a control device that can be used in conjunction with the present invention Figure 9 The figure is a diagram of a storage and calculation evaluation module of a control device that can be used in conjunction with the present invention.

[0052] Serial numbers in the figure: 1. Spot welding machine; 101. First electrode; 102. Second electrode; 103. Gap; 104. Ultrasonic probe; 105. Electrode head contact surface; 106. Weld core; 107. Welding base material; 108. First cooling medium channel; 109. Ultrasonic vibrator; 110. Electrode driving mechanism; 111. Clamp-type fixing frame; 112. Second elastic support; 113. Bending spring; 114. Spring connecting ring; 115. Water inlet; 116. Water outlet; 2. Control device; 201. Host computer; 202. Manual control; 203. Remote control network interface; 204. Basic welding parameter acquisition; 205. Ultrasonic excitation control module; 206. Ultrasonic excitation synchronization module; 207. Non-destructive testing data acquisition; 208. Non-destructive testing synchronization module; 209. Predictive quality analysis; 210. Storage and computing module. DETAILED DESCRIPTION

[0053] See also Figures 1 to 4 The spot welder 1 in the welding equipment is equipped with a clamp-type fixing frame 111. The ends of the clamp-type fixing frame 111 are used to mount a first electrode 101 and a second electrode 102. The first and second electrodes are generally arranged one above the other. Depending on actual needs, the first electrode can be positioned at the bottom or the top. The contact surfaces (front ends) 105 of the electrode tips of the first and second electrodes face each other. The first and second electrodes 101 and 102 both have a hollow structure. The first electrode 101 is equipped with an ultrasonic transducer (e.g., an ultrasonic piezoelectric transducer) 109 for emitting ultrasonic waves. The ultrasonic transducer 109 converts ultrasonic acoustic energy into mechanical vibration energy, providing vibration excitation during the welding process to refine the metal grain structure within the spot weld nugget, reduce weld porosity, and improve product processing quality. The second electrode 102 is equipped with an ultrasonic probe 104 for detecting ultrasonic waves. The ultrasonic probe 104 collects ultrasonic signals throughout the welding process. According to existing technologies, by analyzing the ultrasonic signals, changes in the fusion characteristics of the weld spot during the welding operation can be monitored in real time. By collecting scanning data, the quality of the welding operation can be easily determined.

[0054] The ultrasonic probe and vibrator can be set up according to existing technology to perform the required ultrasonic signal detection on the object located between the two electrodes (for example, the welding base material). Through the matching data processing device, for example, the data processing capability of the existing spot welding machine control device can be utilized to analyze the ultrasonic signal collected by the spot welding machine probe to obtain the detection result.

[0055] A first elastic bracket for fixing the ultrasonic vibrator is provided in the cavity of the first electrode 101, and a second elastic bracket 112 for fixing the ultrasonic probe is provided in the cavity of the second electrode 102, which respectively tighten and fix the ultrasonic vibrator and the ultrasonic probe 104. Both elastic brackets are water-permeable brackets, and are provided with a bottom ring 114 serving as a base for the spring and a plurality of bent springs 113 provided on the bottom ring. When in use, the water-permeable bracket is placed into the electrode cavity, and then the part to be fixed (probe or vibrator) is placed, so that the bracket is located between the front end face of the cavity and the front end face of the part to be fixed, and the bottom ring is attached to the front end inner wall of the cavity. The bent spring extends backward and inward (radially inward) through bending, and the end portion rests on the front end face of the part to be fixed, pushing the part to be fixed backward and pressing it tightly against the fixed structure located behind the part to be fixed.

[0056] A gap 103 is left between the circumference and front end surfaces of the ultrasonic probe (e.g., ultrasonic sensor) and ultrasonic vibrator and the inner wall of the cavity in which they are located, forming a cooling medium channel (a first cooling medium channel and a second cooling medium channel). The second cooling medium channel is provided with a water inlet and a water outlet, which are used as input and output pipes for the cooling medium to achieve forced cooling.

[0057] According to actual conditions, the water inlet 115 and the water outlet 116 of the cooling medium channel (the first cooling medium channel and the second cooling medium channel) can be opened on the clamp-type fixing frame (or on the electrode driving mechanism, if the corresponding electrode is installed on the electrode driving mechanism) to connect the rear end (cup mouth end of the cup-shaped structure) of the corresponding electrode (the first electrode or the second electrode), and connect the area of the corresponding end of the corresponding electrode cavity that is not covered by the ultrasonic voltage vibrator (the position connected to the cooling medium channel), or be opened on the side wall of the rear part of the corresponding electrode, and the water inlet and the water outlet are symmetrically (mirror-symmetrical with respect to any longitudinal section of the cavity) arranged on both sides (on both sides of the symmetry plane), and a partition can be set between the circumference of the ultrasonic vibrator and the inner wall of the cavity to divide the annular gap between the circumference of the ultrasonic vibrator and the inner wall of the cavity into an inlet channel connected to the water inlet and an outlet channel connected to the water outlet. After the cooling medium (for example, cooling water or cooling oil) flows into the water inlet, it flows through the water inlet channel to the gap between the front end face of the ultrasonic vibrator and the cavity, and then flows into the outlet channel and flows out from the outlet.

[0058] Because cooling water flows through the interior of each electrode cavity, it cools the probe, vibrator, and electrodes themselves. Ultrasonic probe 104 and ultrasonic vibrator 109 are immersed in water during operation, adapting to the underwater working environment. This ensures that the ultrasonic probe 104 and ultrasonic vibrator 109 operate within their normal operating temperature range, protecting the sensors. The cooling water also provides an excellent coupling medium for ultrasonic wave propagation, creating a favorable working environment for nondestructive testing. Nondestructive testing can be performed while maintaining the required operating temperature and water pressure.

[0059] The first elastic support 108 and the second elastic support 103 are both water-permeable supports and do not hinder the flow of the cooling medium.

[0060] The elastic brackets (first and second elastic brackets) can be made by stamping and folding stainless steel sheets, or alternatively, by using high-temperature-resistant materials. The mounting bracket secures the sensor in the center, maintaining a certain distance between the inner wall of the electrode cavity and the sensor. Together, the mounting bracket, the inner wall of the electrode cavity, and the sensor form the cooling water inlet and outlet channels.

[0061] The front end surfaces of the first electrode 101 and the second electrode 102 are the electrode tip contact surface 105. During use, the welding portion of the welding base material 107 is located between the first electrode 101 and the second electrode 102, and the electrode tip contact surface 105 is in contact with the welding base material 107. The electrode tip contact surface 105 is in direct contact with the welding base material 107. During the welding process, the electrode tip contact surface 105 is clamped to the surface of the welding base material 107, and the high temperature generated by the current causes the welding base material 107 to be completely fused together. After the welding is completed and the pressure is maintained and the temperature is reduced, a weld nugget 106 is formed between the welding base materials 107.

[0062] The spot welding machine (frame) 1 is provided with a clamp-type fixing frame 111, and an electrode driving mechanism 110 is provided on the clamp-type fixing frame 111. The number of the electrode driving mechanism 110 can usually be one, used to drive a certain electrode to move, and when necessary, can also be two, used to drive two electrodes to move respectively. Figure 2 In the illustrated embodiment, the first electrode 101 is mounted on an electrode driving mechanism 110 (a movable end base of the driving mechanism). Under the action of a driving electrode (or an air cylinder, an oil cylinder, etc.), the electrode driving mechanism 110 drives the electrodes to move toward each other (toward the other electrode), clamps / extrudes the welding base material 107 and maintains a certain pressure to achieve welding.

[0063] The ultrasonic probe 104 may be a suitable ultrasonic sensor.

[0064] The control device and control network of the spot welding machine can be configured according to actual needs. For example, manual control, remote control network interface, basic welding parameter acquisition, ultrasonic excitation control module, ultrasonic excitation synchronization module, non-destructive testing data acquisition, non-destructive testing synchronization module, predictive quality analysis and storage and calculation module can be set, and the host computer can be set.

[0065] The spot welding machine 1 can be equipped with a control device 2, and the ultrasonic analysis and processing device can be integrated into the control device, or the control device can have ultrasonic analysis and processing capabilities with the support of software, and can be connected to the host computer 201 to achieve data interaction and collaborative work.

[0066] See also Figures 5 to 9, the control device of the spot welding machine can be set according to the existing technology to set manual control 202, remote control network interface 203, welding basic parameter acquisition 204, ultrasonic excitation control module 205, ultrasonic excitation synchronization module 206, non-destructive testing data acquisition 207, non-destructive testing synchronization module 208, predictive quality analysis 209 and storage and calculation module 210. The host computer 201 is for the welding process and quality inspection. When it is running in automatic working mode, it issues a control command and sends it to each execution terminal through the internal bus. The data of the execution terminal can be fed back to the host computer 201 to keep the working sequence consistent; manual control 202 is for the welding process and quality inspection. When it is running in manual mode, through manual control 202, the connection terminal is selected to perform parameter setting, live testing, learning teaching, quality judgment setting, and intelligent learning; the remote control network interface 203 is used for the exchange of welding machine power parameters, work execution commands and external control data; welding basic parameter acquisition 2 04 collects real-time data of the welding machine operation process; the ultrasonic excitation control module 205 is an ultrasonic excitation generator control terminal, connected to the ultrasonic vibrator 109 to generate acoustic vibration excitation, and the ultrasonic excitation synchronization module 206 is connected to the ultrasonic vibrator 109 and is a switch that controls whether the ultrasonic excitation is working; the non-destructive testing data acquisition 207 is used to collect non-destructive testing data of the weld point through the ultrasonic probe 104 to obtain scanning images and data of the weld point; the non-destructive testing synchronization module 208 is connected to the ultrasonic probe 104 and controls whether the non-destructive testing data acquisition 207 is working; the predictive quality analysis 209 forms a quality data curve by performing statistical analysis on the collected data, analyzes the quality control trend of the weld point, and issues an alarm when the quality exceeds the historical average (or exceeds the quality control threshold); the storage and calculation module 210 is used to collect and store welding parameters and weld point non-destructive testing data, and judge the welding quality based on the collected non-destructive testing data image.

[0067] When the welding process and quality inspection are running in the automatic working mode, the host computer 201 issues a control command and sends it to each execution terminal through the internal bus. The data of the execution terminal can be fed back to the host computer 201 to keep the working sequence consistent. When the welding process and quality inspection are running in the manual mode, manual operation is performed to select the connection terminal, perform parameter setting, live testing, learning and teaching, quality judgment setting, and intelligent learning.

[0068] The ultrasonic piezoelectric vibrator 109 is started by the ultrasonic excitation synchronization module 206 to generate acoustic vibration excitation, reduce welding porosity, and improve product welding quality. The non-destructive testing synchronization module 208 is started to enable the ultrasonic probe 104 to collect non-destructive testing data of welds, obtain weld data, and provide data support for subsequent predictive quality analysis 209 and storage and calculation module 210. The predictive quality analysis 209 analyzes the welding parameters and quality evaluation data of each weld in the data to form a quality data curve, analyzes the trend of weld quality control, and issues an alarm when the quality exceeds the historical average. The welding parameters and weld non-destructive testing data are stored by the storage and calculation module 210, and the welding quality is determined based on the collected non-destructive testing data image.

[0069] The main functions of each part are: Host computer: The welding process and quality inspection run in automatic working mode. The host computer can issue control commands and send them to each execution terminal through the internal bus. The data of the execution terminal can be fed back to the host computer to keep the working sequence consistent.

[0070] Manual control mode: The welding process and quality inspection are run in manual mode. Through manual operation, select the connection terminal, perform parameter setting, live testing, learning and teaching, quality judgment setting, and intelligent learning.

[0071] Remote control network interface: used for welding machine power parameters, work execution commands and external control data exchange; Basic welding parameter acquisition module: collects real-time data of the welding machine operation process, such as current, voltage, clamping force, clamping time, welding temperature, ambient temperature, shift, especially the pre-reading of the workpiece clamping time point, preheating time start point, preheating time, welding start time point, welding time, post-weld pressure holding time point, pressure holding time and related Figure 1 Extraction and collection of welding machine control time nodes and timing.

[0072] Ultrasonic excitation control module: Ultrasonic excitation generator control terminal, connected to the ultrasonic piezoelectric vibrator to generate acoustic wave vibration excitation.

[0073] Ultrasonic excitation synchronization module: The ultrasonic excitation synchronization module is connected to the ultrasonic piezoelectric vibrator and controls whether the ultrasonic excitation is active. It ensures that the start and end times of ultrasonic excitation are synchronized with the start and end times of welding. It can synchronize the welder's current sensing switch control and the welder's internal timing control.

[0074] Nondestructive testing data acquisition module: This module uses ultrasonic probes to collect nondestructive testing data for welds, obtaining A-scan and C-scan images of the welds. Nondestructive testing can be set to either full-time acquisition or pressure-holding acquisition.

[0075] NDT Synchronization Module: This module connects to the ultrasonic probe and controls the on / off status of NDT data collection. This ensures that the NDT probe's start and end times are synchronized with the welding pressure hold time. This synchronization is achieved through both the welder's current sensing switch and the welder's internal timing control.

[0076] Predictive quality analysis module: The data analysis software records the welding parameters and quality evaluation data of each solder joint, forms a quality data curve, analyzes the trend of solder joint quality control, and issues an alarm when the quality exceeds the historical average.

[0077] Storage and calculation module: stores welding parameters and non-destructive testing data of weld points, and determines welding quality based on the collected non-destructive testing data images.

[0078] Under the existing technical background, the following ultrasonic tests can be mainly implemented: Ultrasonic nondestructive testing A-scan: reflects the longitudinal ultrasonic feedback wave length of the solder joint at a specific moment, detects whether there are defects such as pores, desoldering, burn-through, etc. at a certain point, and reflects the defect range perpendicular to the ultrasonic propagation direction; Ultrasonic nondestructive testing B-scan: reflects the longitudinal ultrasonic transmission feedback wave length of the weld point in a continuous time period, and detects the fusion change of a certain point during the welding process; Ultrasonic non-destructive testing C-scan: It is a cross-sectional view at a certain depth in the longitudinal direction of the weld to check whether there are pores, desoldering, or penetration. The effective area of the weld core and the welding quality rating can be calculated based on the cross-sectional area.

[0079] The basic / main working process of the present invention is as follows: the spot welding machine is powered on, and the electrode driving mechanism 110 drives the first electrode 101 to move upward under the action of the driving mechanism, and the welding base material 107 is clamped between the first electrode 101 and the second electrode 102. The voltage applied to the first electrode 101 and the second electrode 102 causes the current to pass through the welding base material 107, and the resistance effect generates heat energy, and the welding base material 107 is fused. After the welding is completed, the pressure is continuously tightened and maintained for a period of time, so that the welding point base material (107) is completely fused together to form a weld core.

[0080] Depending on actual needs, during welding, the ultrasonic vibrator and ultrasonic probe 104 operate to perform ultrasonic testing. This allows for real-time monitoring of changes in weld fusion characteristics throughout the welding process. Post-weld nondestructive testing of the weld can also be performed after or during the pressure-holding phase. Ultrasonic scanning data is collected by the probe and sent to a corresponding data processing device for analysis and assessment of weld quality. Furthermore, since ultrasonic acoustic energy is converted into mechanical vibration energy during welding, providing vibration excitation, it refines the metal grain structure within the spot weld nugget 106, reduces weld porosity, and improves product weld quality.

[0081] Welding and inspection workflows may include: Step 1: Press the electrode against the workpiece, start the welding current, and form a nugget; Step 2: Enter the pressure holding stage (50-200ms), and maintain the electrode pressure (2-4kN) after stopping the current; Step 3: 10ms before the pressure holding stage, trigger the ultrasonic probe, transmit the pulse wave, and receive the echo signal; Step 4: Extract echo features (time domain amplitude, frequency domain attenuation slope), input them into the judgment module, and determine the defect type; Step 5: When weld nuggets or defects are detected, intelligent learning is performed to level the weld quality.

[0082] Example 1. Welding and quality inspection: The welder is powered on for self-inspection, clamping the base material, powering on for preheating, welding with a high current, cooling under pressure, and releasing the clamp to complete a welding cycle. The welding machine working sequence, ultrasonic excitation, and non-destructive testing sequence are matched. Ultrasonic excitation works during the spot welding period to refine the weld nugget grains and increase the metal grain aggregation rate. Non-destructive testing is performed throughout the entire welding process, with A-scan and C-scan being performed from the start of welding to the pressure-holding cooling stage, recording the inspection data of the entire welding process. Pressure-holding non-destructive testing is performed during the welding pressure-holding cooling stage to collect A-scan, B-scan, and C-scan data. The A-scan determines whether there are welding defects, the B-scan reflects the fusion characteristics of the test point within a continuous time period, and the C-scan evaluates the weld nugget size and quality rating.

[0083] When the electric welder is welding, cooling water passes through the water-permeable shrapnel bracket to cool down the welding machine electrode head A. Cooling water passes through the water-permeable shrapnel bracket to cool down the welding machine electrode head B.

[0084] When the welding machine is preheating and welding, copper electrode cap A and copper electrode cap B are energized at the same time to heat, fuse and maintain pressure on the base material to form a weld nugget.

[0085] Example 2. Automatic welding mode operation process: The host computer initiates self-test, communicates with the welder via the remote control network interface, transmits welding parameters, and activates the welding power supply. The basic welding parameter acquisition module records the welding parameters and environmental parameters during the welding process. When the welding power supply discharges a second time, the ultrasonic excitation synchronization module triggers the ultrasonic excitation control module, which works with the connected ultrasonic piezoelectric vibrator to convert ultrasonic waves into mechanical vibrations. The non-destructive testing synchronization module initiates non-destructive testing (NDT), with options for full-time NDT or pressure-maintained NDT. The ultrasonic probe performs inspections, collects NDT data, and sends the collected data to the storage and computing module for data storage and quality control, resulting in a qualified or unqualified result and a warning for unqualified data.

[0086] Predictive quality analysis statistical data to form a quality trend curve.

[0087] The intelligent evaluation learning module obtains the quality judgment results of the storage and computing modules, analyzes the scanning data, and automatically iterates the quality evaluation specimens.

[0088] Example 3. Working process of manual control mode: set parameters of the ultrasonic excitation control module to control the working parameters of the ultrasonic piezoelectric vibrator; set parameters of the non-destructive testing synchronization module to control the ultrasonic probe detection working period, and set it to full-time non-destructive testing or pressure-maintaining non-destructive testing mode; design predictive quality analysis and set the quality analysis quality deviation rating bandwidth; set the storage and computing module and set the quality rating specimen; perform welding test in the welding machine live mode, obtain initial quality qualified specimens through non-destructive testing data collection, and set them as the initial value of the intelligent evaluation learning module. Example 4. Ultrasonic excitation control logic: In automatic mode, the host computer sends a start command, synchronizing other devices and programs to a standby state and performing self-tests on parameters such as the external power supply and ultrasonic frequency. Ultrasonic excitation can be triggered simultaneously in two ways. The first uses a host computer as a clock to control timing, activating ultrasonic excitation during the welding period according to the programmed sequence and stopping it at the end of welding. The second uses an external current sensing switch. When the secondary power supply current of the welding machine is turned on, the current sensing switch opens, activating ultrasonic excitation, and stops when the power supply ends. When ultrasonic excitation ends, data is sent to the storage and computation evaluation module.

[0089] In manual control mode, start the ultrasonic excitation standby state through the physical button or touch screen button mode, set the ultrasonic excitation control parameters, select the ultrasonic excitation trigger mode (program automatic synchronization welding machine or hardware sensor switch synchronization), the ultrasonic excitation trigger starts working, and when the ultrasonic excitation is completed, the data will be sent to the storage and calculation evaluation module.

[0090] Example 5. Nondestructive testing control logic: In automatic mode, the host computer controls self-test and synchronizes welding to start nondestructive testing according to the preset mode. After the test is completed, the generated test data and parameters and reports are sent to the storage and calculation evaluation module as big data statistical samples.

[0091] In manual mode, set parameters, manually select the mode and start the non-destructive testing trigger, start non-destructive testing during synchronous welding, generate test data and send parameters and reports to the storage and calculation evaluation module as big data statistical samples.

[0092] Example 6. Intelligent quality evaluation learning logic: In automatic mode, the host computer controls and initializes the quality evaluation specimens based on historical data. A / C scanning of a specific good base material is compared and the good data is automatically extracted and iterated. The welding parameters and ultrasonic acquisition images for optimal welding quality evaluation are extracted. Historical data is compared to generate good evaluation reference samples. Iterative reference data is produced and sent to the storage and calculation evaluation module to complete intelligent iterative learning.

[0093] In manual mode, manually collect the most recent non-destructive testing data of the weld, or perform a live test once, and set it as the initial value of the quality rating; perform teaching flaw detection data optimization, manually select the best and reset the initial value of the good product, compare historical data to generate excellent evaluation reference samples, and send them to the storage and calculation evaluation module to complete intelligent iterative learning.

[0094] Example 7. Storage and calculation evaluation: 1) Storage function: The welding parameters, environmental parameters, ultrasonic excitation, non-destructive testing parameters and scanning data during the welding process are stored in the time sequence of a single weld process; 2) Calculation and Evaluation Function: Compares the A-scan ultrasonic feedback pattern to determine whether welding defects exist and determines whether to issue a warning based on the rating criteria. C-scans are analyzed to generate a continuous depth-level weld quality pattern. Software is used to evaluate the weld nugget area in the base metal fusion zone and determine the quality grade.

[0095] In automatic mode, the host computer controls, self-test starts, extracts the most recent test data, compares and calculates the A / C scan data, generates the evaluation results, stores the results, determines whether there is an out-of-tolerance warning, compares the last historical data, and if it is the optimal data, matches the welding parameters and test results to the most accurate sample as the initial value for quality iteration; if it is not the optimal data, keeps the record and storage.

[0096] In automatic mode, start manually, select test data manually, manually teach and import A / C scan data of flaw detection, calculate and generate evaluation results, store the results, determine whether there is an out-of-tolerance warning, compare the last historical data, and if it is the optimal data, match the welding parameters and test results to the best sample as the initial value of quality iteration. If it is not the optimal data, keep the record and store it.

[0097] Example 8. Selectable welding process and detection mode: 1) Optional automatic or manual mode of resistance welding machine; 2) The ultrasonic excitation (ultrasonic piezoelectric vibrator) can be selected to be on or off. The ultrasonic non-destructive testing (ultrasonic probe) can be selected to be on or off. The ultrasonic non-destructive testing (ultrasonic probe) can be selected to be in full-time testing or pressure-holding testing mode. The non-destructive testing A, B, and C scans can be selected to be on in any one, any two, or all three.

[0098] Example 9. Welding Data Display and Retrieval: After the welding system is powered on, the parameter recording device is powered on, and the data acquisition terminal starts operating. When the welder begins welding, the acquisition card extracts data and transmits it to the memory and display device. The data is then calculated and evaluated for comparison. If the data is within the normal range, no alarm is triggered. If it is out of range, an alarm is triggered. Real-time data can be displayed and stored in the background. Real-time data can be displayed and stored at any time.

[0099] Compared with existing conventional resistance spot welding machines, the welding equipment of the present invention has the following characteristics: 1) An ultrasonic probe and vibrator are installed in the electrode, which can perform real-time ultrasonic self-detection during the welding process, so that the welder has ultrasonic non-destructive testing function; 2) While ensuring the water cooling function of the second electrode, the installation and setting of the ultrasonic flaw detection probe is realized. The ultrasonic probe (water immersion type) is fixed through the built-in water-permeable spring bracket to adapt to the corresponding working environment; 3) An ultrasonic vibrator is installed in the first electrode to provide vibration excitation independently during the welding process or to form vibration excitation based on ultrasonic detection, thereby refining the metal grain structure inside the spot welding core and reducing welding porosity; 4) Based on existing technologies, through appropriate ultrasonic data acquisition and data analysis, A-scan (longitudinal waveform reflection waveform), B-scan time-series scan diagram, and C-scan (longitudinal depth cross-sectional diagram) images can be generated, and ultrasonic inspection reports can be automatically generated with the support of software. For example, the ultrasonic A-scan waveform image can be used to determine whether there are pores and unfused defects, and the C-scan image can be used to determine the weld core area and fusion area of the weld spot, thereby determining whether the quality is qualified; 5) With the support of existing information technology, the welding quality error band can be set, the quality trend can be judged by the weld quality data, and the big data can be used for predictive judgment to take quality intervention measures; 6) With the support of existing information technology, a learning mode for welding machine quality determination can be set. When the welding base material or the base material thickness changes, manual teaching can be performed to collect weld quality inspection data, set the welding quality range, and perform quality determination.

[0100] Unless otherwise specified or when one preferred or optional technical means is a further limitation of another technical means, the preferred and optional technical means disclosed in the present invention can be arbitrarily combined to form several different specific implementation methods.

Claims

1. Welding equipment comprising a resistance spot welder and a control device for the resistance spot welder, wherein the resistance spot welder is provided with an electrode pair for resistance spot welding, the electrode pair comprising a first electrode and a second electrode arranged opposite to each other, characterized in that The first electrode and the second electrode are respectively provided with an ultrasonic vibrator and an ultrasonic probe for ultrasonic detection, which are used to perform ultrasonic detection on the welding base material located between the two electrodes. The ultrasonic detection signal output of the ultrasonic probe is connected to the control device, and the control system of the resistance spot welding machine obtains the ultrasonic detection result based on the ultrasonic detection signal analysis.

2. The welding device according to claim 1, characterized in that The first electrode and the second electrode both adopt a hollow structure and are provided with a cavity. The ultrasonic vibrator and the ultrasonic probe are respectively installed in the cavity of the first electrode and the second electrode.

3. The welding device according to claim 2, characterized in that A first elastic support for pressing and fixing the ultrasonic vibrator is provided in the cavity of the first electrode, and a second elastic support for pressing and fixing the ultrasonic probe is provided in the cavity of the second electrode.

4. The welding device according to claim 1, characterized in that The spot welding machine is provided with a clamp-type fixing frame, the first electrode and the second electrode are respectively installed at both ends of the clamp-type fixing frame, and at least one of the first electrode and the second electrode is provided with an electrode driving mechanism, and a movable connection on the clamp-type fixing frame is achieved through the corresponding electrode driving mechanism.

5. The welding device according to any one of claims 1 to 4, characterized in that The ultrasonic vibrator adopts an ultrasonic vibrator, which is located at the axis position of the cavity of the first electrode, and a gap is left between its circumference and end surface and the inner wall of the corresponding cavity to form a first cooling medium channel. The first cooling medium channel is provided with a water inlet and a water outlet, which are used to connect the input pipe and output pipe of the cooling medium to achieve forced cooling. The ultrasonic probe adopts an immersion ultrasonic probe, which is located at the axis position of the cavity of the second electrode, and a gap is left between its circumference and end surface and the inner wall of the corresponding cavity to form a second cooling medium channel. The second cooling medium channel is provided with a water inlet and a water outlet, which are used for the input pipe and output pipe of the cooling medium to achieve forced cooling.

6. The welding device according to claim 5, characterized in that The first elastic support is a water-permeable support, and the second elastic support is a water-permeable support.

7. The welding device according to any one of claims 1 to 4, characterized in that The output of the ultrasonic probe is connected to the control device of the spot welder.

8. The welding device according to claim 7, characterized in that The control device constitutes a welding control system, or the control device is connected to a host computer and together with the host computer constitutes a welding control system.

9. The welding device according to claim 8, characterized in that The control device is provided with a basic welding parameter acquisition module, an ultrasonic excitation control module, an ultrasonic excitation synchronization module, a non-destructive testing data acquisition module, a non-destructive testing synchronization module and a predictive quality analysis module. The basic welding parameter acquisition module is used to collect real-time data of the welding machine operation process; the ultrasonic excitation control module is used to implement synchronous control of ultrasonic excitation and welding; the ultrasonic excitation synchronization module is used to implement synchronous control of ultrasonic excitation and welding; the non-destructive testing data acquisition module is used to collect ultrasonic detection data of the ultrasonic probe; the non-destructive testing synchronization module is used to implement synchronous control of ultrasonic detection, welding and welding pressure maintenance; the predictive quality analysis module is used to implement welding quality prediction analysis and evaluation based on real-time welding process data and ultrasonic detection data.

10. Welding quality detection method, characterized in that Resistance spot welding is performed using the welding equipment according to any one of claims 1 to 9. During the welding process, real-time ultrasonic detection of the weld spot is performed using the ultrasonic vibrator and the ultrasonic probe, and the welding process and / or welding quality are analyzed based on the ultrasonic detection data sent by the ultrasonic probe.

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