Automatic ultrasonic detection equipment and method for differential welding assembly

Abstract

The invention provides an automatic ultrasonic detection device and method for a differential mechanism welding assembly, and the device comprises an ultrathin sheet-shaped ultrasonic probe which is installed below a welding seam of the differential mechanism welding assembly in a height-adjustable manner; the active jet flow coupling system forms a stable sound wave conduction medium layer between the ultrathin sheet-shaped ultrasonic probe and the welding seam; the ultrasonic analyzer and control unit is connected with the ultrathin sheet-shaped ultrasonic probe and is used for collecting ultrasonic echo signals and analyzing, identifying and quantifying weld defects in real time by adopting a perimeter algorithm, and when defect echoes exceeding a preset threshold value are found, perimeter equivalent calculation is immediately started and all the defects are automatically graded; outputting a final judgment conclusion of qualification or not; and the mechanical scanning mechanism is used for clamping and driving the differential mechanism welding assembly to rotate. According to the invention, efficient, accurate and reliable automatic detection which is deeply fused with an intelligent manufacturing system can be realized.

Description

Technical Field

[0001] The present invention belongs to the technical fields of nondestructive testing and intelligent manufacturing, and particularly relates to an automated ultrasonic testing device and method for differential welding assemblies. Background Art

[0002] Differential welding assemblies are key safety components in the automotive drive system, and the quality of their welds directly affects the safety and reliability of the entire vehicle. Ultrasonic testing is an effective means to evaluate the internal quality of welds. However, due to the complex structure of differential welding assemblies, the weld areas to be inspected (such as circumferential welds and saddle-shaped welds) usually have a narrow space and irregular geometric shapes, resulting in the following severe technical bottlenecks for conventional ultrasonic testing: 1. Poor probe accessibility: The weld area is often closely surrounded by the surrounding matrix structure, and the operating space is extremely cramped. Due to the limitations of the size and shape of traditional circular ultrasonic probes, they cannot approach and scan the entire weld cross-section at the optimal sound beam incident angle, resulting in detection blind spots. In particular, defects in the weld root and fusion line areas are extremely likely to be missed.

[0003] 2. Extremely unstable acoustic coupling: When using the traditional immersion coupling method, after the assembly is immersed in the coupling liquid, sealed air cavities are easily formed at the complex surfaces around the weld (such as the gaps between stiffeners, sleeves and the housing). The air layer between the probe and the workpiece interface causes a serious mismatch in acoustic impedance (Z) {Z(air) << Z(water)Z(steel)}, resulting in almost total reflection of ultrasonic waves at the interface and unable to effectively penetrate into the weld area for detection.

[0004] 3. Inconsistent weld defect quantification standards: The defect evaluation algorithm cores used in ultrasonic devices of different manufacturers are different. For example, the reference device uses a perimeter-based algorithm to evaluate the equivalent size and harmfulness of defects such as pores and slag in welds, while other devices may use an area algorithm, which leads to systematic deviations in the acceptance grading results for the same weld defect and poses a great risk to quality control.

[0005] 4. Disconnection between inspection and production management: Existing inspection devices are mostly information islands, lacking the ability of automatic grading decision-making based on preset standards, and the generation of inspection reports and data entry rely on manual labor. They cannot upload the results to the manufacturing execution system (MES) in real time and automatically, and cannot meet the stringent requirements of digital factories for the full-process automation and traceability of quality inspection. Summary of the Invention[[ID=②]]

[0006] To overcome the deficiencies of the prior art, the present invention proposes an automated ultrasonic testing device and method for differential welding assemblies, realizing efficient, accurate, reliable and deeply integrated automated testing with the intelligent manufacturing system.

[0007] The technical solution adopted in this invention is: An automated ultrasonic testing device for differential welded components, comprising: An ultra-thin sheet-like ultrasonic probe is installed at an adjustable height below the weld seam of the differential welding assembly; An active jet coupling system forms a stable acoustic wave transmission medium layer between an ultrathin sheet-like ultrasonic probe and the weld. The ultrasonic analyzer and control unit are connected to the ultra-thin sheet-like ultrasonic probe to collect ultrasonic echo signals and perform real-time analysis using a perimeter algorithm to identify and quantify weld defects. When a defect echo exceeding a preset threshold is detected, the perimeter equivalent calculation is immediately initiated and all defects are automatically graded, outputting a final judgment on whether the weld is qualified. A mechanical scanning mechanism is used to clamp and drive the differential welding assembly to rotate; The data integration and communication module, which connects to the ultrasonic analyzer and control unit, is used to automatically generate test reports and upload test data to the manufacturing execution system; The alarm and execution unit is connected to the ultrasonic analyzer and control unit. It is used to trigger an alarm and output an interception signal when the final judgment is that the result is unqualified.

[0008] Furthermore, the front end of the ultrathin sheet-like ultrasonic probe is a sheet-like structure no larger than 3mm, which contains a rectangular piezoelectric crystal.

[0009] Furthermore, the piezoelectric wafer has a dimension of no more than 2 mm in the thickness direction of the ultrathin sheet-like ultrasonic probe and a dimension of 5 mm to 3 mm in the length direction.

[0010] Furthermore, the ultrathin sheet-like ultrasonic probe operates at a frequency of 5MHz to 15MHz.

[0011] Furthermore, the active jet coupling system includes an adjustable flow supply device and a nozzle disposed near the ultra-thin sheet-like ultrasonic probe. The nozzle is connected to the adjustable flow supply device, and the spray direction of the nozzle is adjustable.

[0012] Furthermore, the adjustable flow supply device is a variable frequency water pump or a servo proportional valve, used to provide coupling fluid with an adjustable flow rate in the range of 0.5L / min to 2.0L / min.

[0013] Furthermore, the spray direction of the nozzle forms an angle of 60° to 80° with the detection surface of the ultrathin sheet-like ultrasonic probe.

[0014] Furthermore, the ultrasonic analyzer and control unit have the following built-in features: The weld defect evaluation module is used to execute a quantization algorithm based on defect perimeter equivalent to accurately quantify and rate common defects in welds. The automatic rating module is used to automatically compare the defect analysis results with the preset acceptance criteria and output a final judgment of whether the defect is qualified or unqualified.

[0015] Furthermore, the mechanical scanning mechanism is a precision rotary table or a lathe-type chuck structure.

[0016] The specific steps of the testing method using the automated ultrasonic testing equipment for differential welded components described above are as follows: S1, Fix the differential welding assembly to the mechanical scanning mechanism; S2, activate the active jet coupling system to spray coupling fluid between the fixedly installed ultra-thin sheet ultrasonic probe and the weld area to be inspected of the differential welding assembly to form a stable acoustic wave transmission medium layer; S3, the mechanical scanning mechanism drives the differential welding assembly to rotate, while the ultrasonic analyzer and control unit excite the ultra-thin sheet-like ultrasonic probe and collect ultrasonic echo signals; S4, the ultrasonic analyzer and control unit use the perimeter algorithm for real-time analysis, identify and quantify weld defects. When a defect echo exceeding the preset threshold is found, the perimeter equivalent calculation is immediately started and all defects are automatically graded, and the final judgment conclusion on whether it is qualified is output. S5 automatically generates inspection reports through the data integration and communication module, and uploads the inspection data and grading conclusions to the manufacturing execution system; S6, if the workpiece is deemed qualified, the production line is controlled to release it; if the workpiece is deemed unqualified, the alarm is triggered by the alarm and execution unit and a signal is output to intercept the differential welding assembly.

[0017] The beneficial effects of this invention are: 1. Achieved comprehensive blind-spot-free inspection of complex welds: Through the innovative ultra-thin sheet probe design, it breaks through the physical limitations of traditional circular probes, enabling it to flexibly enter and scan the narrow space around the weld, and cover key dangerous areas such as the weld root and fusion line with the optimal sound beam angle, significantly improving the detection rate of dangerous defects and fundamentally eliminating blind spots in the inspection.

[0018] 2. Ensures acoustic coupling reliability under extreme conditions: By using active jet coupling technology, stable and controllable laminar flow is used to actively displace and suppress air gaps, achieving a stable coupling rate of over 99% in complex and narrow spaces where traditional methods cannot couple. This provides a fundamental guarantee for obtaining high signal-to-noise ratio and high repeatability ultrasonic signals from welds.

[0019] 3. Unified authoritative evaluation criteria for weld defects: By using the same perimeter algorithm as the benchmark equipment in the built-in analyzer as the defect evaluation kernel, the consistency of the test results at the principle level is ensured, the system deviation caused by different algorithms is eliminated, and the acceptance rating results are accurate and reliable, and seamlessly integrated with the established quality system.

[0020] 4. Achieved intelligent closed-loop control from detection to judgment to execution: This invention, through an automatic judgment module and an alarm and execution unit, realizes unmanned decision-making from detection to execution. The equipment can make immediate decisions: qualified workpieces are automatically released, and unqualified workpieces are alarmed and intercepted in real time. This completely eliminates the reliance on manual judgment, eliminates misjudgments and omissions, and achieves seamless integration of quality control within the production cycle.

[0021] 5. Achieved digitalization and full-process traceability of inspection data: Through automatic report generation and MES integration, seamless integration of quality inspection and production management was realized. All inspection results, defect maps, and workpiece information are automatically uploaded to the MES system, providing a solid data foundation for product quality big data analysis, production process optimization, and full lifecycle traceability, greatly improving the efficiency and digitalization level of quality management. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the present invention.

[0023] Figure 2 This is a schematic diagram of the structure of the ultrathin sheet-like ultrasonic probe and the active jet coupling system of the present invention.

[0024] Figure 3 This is a schematic diagram of the structure of the active jet coupling system of the present invention for forming water mist.

[0025] Figure 4 This is a schematic diagram of the differential welding assembly of the present invention. Detailed Implementation

[0026] The present invention will be further described below with reference to specific embodiments, but the invention is not limited to these specific embodiments. Those skilled in the art should recognize that the present invention covers all alternatives, improvements and equivalents that may be included within the scope of the claims.

[0027] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and 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 of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more, unless otherwise expressly defined.

[0028] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0029] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0030] See Figure 1-3 This embodiment provides an automated ultrasonic testing device for differential welding components, comprising: An ultra-thin sheet-like ultrasonic probe 100 is installed at an adjustable height below the weld seam of the differential welding assembly 200; An active jet coupling system 300 forms a stable acoustic wave transmission medium layer between an ultra-thin sheet-like ultrasonic probe 100 and the weld. The ultrasonic analyzer and control unit 400 is connected to the ultra-thin sheet-like ultrasonic probe 100. It is used to collect ultrasonic echo signals and perform real-time analysis using a perimeter algorithm to identify and quantify weld defects. When a defect echo exceeding a preset threshold is detected, the perimeter equivalent calculation is immediately started and all defects are automatically graded, and the final judgment conclusion on whether it is qualified is output. A mechanical scanning mechanism 500 is used to clamp and drive the differential welding assembly 200 to rotate. The data integration and communication module, which is connected to the ultrasonic analyzer and control unit 400, is used to automatically generate test reports and upload test data to the manufacturing execution system; The alarm and execution unit is connected to the ultrasonic analyzer and control unit 400. It is used to trigger an alarm and output an interception signal when the final judgment is that the result is unqualified.

[0031] The ultrathin sheet-like ultrasonic probe 100 described in this embodiment has a sheet-like structure at its front end that is no larger than 3 mm, which can adapt to the extremely narrow scanning space around the weld. The ultrathin sheet-like ultrasonic probe 100 incorporates a rectangular piezoelectric crystal. The piezoelectric crystal has a dimension of no more than 2 mm in the thickness direction and a dimension of 5 mm to 3 mm in the length direction of the ultrathin sheet-like ultrasonic probe. The operating frequency of the ultrathin sheet-like ultrasonic probe 100 is 5 MHz to 15 MHz, preferably 7.5 MHz, to achieve the best balance between penetration and resolution, and to adapt to the detection of coarse-grained structures in welds.

[0032] The active jet coupling system 200 described in this embodiment includes an adjustable flow supply device 310 and a nozzle 320 disposed near the ultrathin sheet-shaped ultrasonic probe 100. The nozzle 320 is connected to the adjustable flow supply device 310, and the spray direction of the nozzle 320 is adjustable. The adjustable flow supply device 310 is a variable frequency water pump or a servo proportional valve, used to provide coupling fluid with an adjustable flow rate in the range of 0.5 L / min to 2.0 L / min. The spray direction of the nozzle 320 forms an angle of 60° to 80° with the detection surface of the ultrathin sheet-shaped ultrasonic probe 100. The nozzle 320 directionally sprays coupling fluid into the narrow gap between the ultrathin sheet-shaped ultrasonic probe 100 and the weld area of ​​the workpiece, forming a stable laminar flow to continuously displace and suppress air in the gap, ensuring the formation of a continuous, high acoustic impedance-matched acoustic wave transmission medium layer.

[0033] The ultrasonic analyzer and control unit 400 described in this embodiment have the following built-in features: The weld defect evaluation module is used to execute a quantization algorithm based on defect perimeter equivalent (i.e., perimeter algorithm) to accurately quantify and rate common defects in welds. The automatic rating module is used to automatically compare the defect analysis results with the preset acceptance criteria and output a final judgment of whether the defect is qualified or unqualified.

[0034] The quantization algorithm based on defect perimeter equivalent is used to convert the defect echo signal into a defect equivalent size that is consistent with the perimeter algorithm used by the reference ultrasonic testing equipment.

[0035] The mechanical scanning mechanism 500 described in this embodiment is a precision rotary table or lathe-type chuck structure, used to precisely clamp the differential welding assembly 200 and drive the workpiece to rotate around its axis. The ultra-thin sheet-like ultrasonic probe 100 is fixedly mounted relative to the frame or only performs axial feed movement, thereby achieving high-precision relative movement between the probe and the workpiece along the weld seam trajectory.

[0036] The data integration and communication module described in this embodiment communicates with the manufacturing execution system via the industrial Ethernet protocol. This module automatically acquires complete test data from the ultrasonic analyzer and control unit 400 and generates a structured test report. It has a standard industrial communication interface (TCP / IP) for automatically uploading the test report and key data to the manufacturing execution system (MES).

[0037] The alarm and execution unit described in this embodiment includes an audible and visual alarm. Upon receiving the "non-conforming" judgment, the audible and visual alarm is immediately triggered to issue a warning. Simultaneously, an interception signal is sent to the production line control system to prevent non-conforming workpieces from flowing into the next process.

[0038] The testing method of the automated ultrasonic testing equipment for differential welding components described in this embodiment has the following specific steps: S1, Fix the differential welding assembly 200 to the mechanical scanning mechanism 500; S2, activate the active jet coupling system 300, spray coupling fluid between the fixedly installed ultra-thin sheet ultrasonic probe 100 and the weld area 201 to be inspected of the differential welding assembly 200 to form a stable acoustic wave transmission medium layer 600, i.e., coupling water curtain. S3, the mechanical scanning mechanism 500 drives the differential welding assembly 200 to rotate, while the ultrasonic analyzer and control unit 400 excite the ultra-thin sheet ultrasonic probe 100 and collect ultrasonic echo signals. S4, the ultrasonic analyzer and control unit 400 uses a perimeter algorithm for real-time analysis, identifies and quantifies weld defects. When a defect echo exceeding the preset threshold is detected, the perimeter equivalent calculation is immediately started and all defects are automatically graded, and the final judgment conclusion on whether it is qualified is output. S5 automatically generates inspection reports through the data integration and communication module, and uploads the inspection data and grading conclusions to the manufacturing execution system; S6, if the workpiece is deemed qualified, the production line is controlled to release it; if the workpiece is deemed unqualified, an alarm is triggered by the alarm and execution unit and a signal is output to intercept the differential welding assembly 200.

[0039] Specific implementation examples of this invention are as follows: This embodiment is used to inspect the circumferential weld between a certain type of differential housing and a drive flange. The weld is located below the flange, with a peripheral clearance of only 4.5mm, and 100% inspection of incomplete penetration defects at the root of weld 202 is required.

[0040] The implementation process is as follows: 1. Equipment configuration and installation: An ultra-thin sheet-shaped ultrasonic probe 100 with a thickness of 3mm, a chip size of 3mm×4mm, and a center frequency of 7.5MHz was selected.

[0041] The ultra-thin sheet-shaped ultrasonic probe 100 is rigidly fixed to the frame by a bracket, and its position and angle are adjusted to ensure that the sound beam can be accurately aligned with the root of the weld 202.

[0042] The differential welding assembly 200 is clamped onto a precision rotary table (i.e., mechanical scanning mechanism 500) driven by a servo motor.

[0043] 2. Workpiece clamping and inspection start-up: The detection program is started on the human-machine interface of the ultrasonic analyzer and control unit 400. In this embodiment, the Waygate USM100 device has been modified with an algorithm.

[0044] 3. Automatic coupling and scanning detection: The system first starts the active jet coupling system 300. The variable frequency water pump outputs coupling fluid (water) at a flow rate of 1.2 L / min. The fluid forms a stable laminar flow through the nozzle 320, instantly squeezing out the air between the ultra-thin sheet-like ultrasonic probe 100 and the differential welding assembly 200, forming a uniform coupling water curtain.

[0045] Subsequently, the mechanical scanning mechanism 500 drives the differential welding assembly 200 to rotate at a constant speed around its central axis, thereby achieving a spiral full-coverage scan of the entire circumferential weld.

[0046] 4. Signal Processing and Intelligent Classification: The ultrasonic analyzer and control unit 400 acquires, amplifies, and digitizes ultrasonic echo signals in real time. Its built-in weld defect evaluation module (reconstructed into a perimeter algorithm) analyzes the signals in real time, and immediately initiates perimeter equivalent calculation when a defect echo exceeding a preset threshold is detected.

[0047] After the inspection is completed, the automatic grading module automatically grades all defects according to the preset weld acceptance standards (e.g., the equivalent circumference of a single pore shall not exceed Φ1.0mm) and generates a final conclusion of "qualified" or "unqualified".

[0048] 5. Data upload and closed-loop control: The data integration and communication module automatically acquires complete test data from the ultrasonic analyzer and control unit 400, automatically generates standardized test reports (such as PDF format) that meet quality system requirements, and stores them on a local server. Simultaneously, this module uploads key data from the test reports to the shop floor-level Manufacturing Execution System (MES) in real time via an industrial Ethernet interface.

[0049] Intelligent classification and process control: (1) If it is determined to be "qualified": the system sends a "qualified release" signal to the production line PLC, and the workpiece is automatically transferred to the unloading area.

[0050] (2) If the workpiece is determined to be "non-conforming": the system immediately activates the red warning light and buzzer through the alarm and execution unit, and sends a "non-conforming interception" signal to the production line PLC, triggering actions such as stopping the production line and activating the push rod to remove the workpiece to the rework area. All alarm and interception events are bound to the workpiece ID and uploaded to the MES system together.

[0051] Effect verification: To verify the effectiveness of this invention, rigorous comparative tests were conducted: (1) Test objects: a set of weld comparison test blocks containing artificially simulated defects (such as Φ0.5mm flat bottom hole), and a batch of real differential welding components extracted from the production line.

[0052] (2) Comparison benchmark: Industry-recognized ultrasonic flaw detection equipment.

[0053] (3) Test results: (a) Defect detection rate: The detection rate of artificial defects in the equipment of the present invention is 100%.

[0054] (b) Quantitative consistency: For all detectable defects, the maximum relative error of the perimeter equivalent size is ±0.3%, and the amplitude fluctuation range is within ±0.02dB, which is far below the industry-standard allowable error of ±2dB.

[0055] (c) Acceptance rating consistency: In the random inspection of actual workpieces, the final rating results of "pass / fail" given by the two machines are 100% consistent.

[0056] (4) Automation and traceability: Successfully achieved 100% automatic classification, report generation, MES data uploading and closed-loop control of qualified release / unqualified interception.

[0057] Test results show that the equipment provided by this invention not only completely solves the accessibility and coupling problem of differential welding components, but also achieves industry-leading levels in terms of detection capabilities, intelligence level, and integration with the production system, fully meeting the stringent requirements of large-scale industrial production for quality inspection.

[0058] This invention achieves comprehensive, blind-spot-free detection of complex welds: Through an innovative ultra-thin sheet-like probe design, it overcomes the physical limitations of traditional circular probes, enabling flexible entry and scanning of the narrow space surrounding the weld. It covers critical hazardous areas such as the weld root and fusion line with optimal sound beam angle, significantly improving the detection rate of dangerous defects and fundamentally eliminating detection blind spots. It ensures reliable acoustic coupling under extreme conditions: Utilizing active jet coupling technology, it actively displaces and suppresses air gaps using stable and controllable laminar flow, achieving a stable coupling rate exceeding 99% in complex, confined spaces where traditional methods are ineffective. This provides a fundamental guarantee for obtaining high signal-to-noise ratio and high repeatability ultrasonic signals from welds. It unifies the authoritative evaluation criteria for weld defects: By employing a perimeter algorithm consistent with benchmark equipment as the defect evaluation kernel in the built-in analyzer, it ensures the consistency of detection results at the principle level, eliminating systemic biases caused by different algorithms. This makes the acceptance rating results accurate and reliable, seamlessly integrating with the established quality system. This invention achieves intelligent closed-loop control from detection to judgment to execution: Through an automatic judgment module and alarm and execution units, it realizes unmanned decision-making from detection to execution. The equipment can make immediate decisions: qualified workpieces are automatically released, and unqualified workpieces are alarmed and intercepted in real time. This completely eliminates the reliance on manual judgment, eliminates misjudgments and omissions, and achieves seamless integration of quality control within the production cycle. It also achieves the digitization of inspection data and full-process traceability: Through automatic report generation and MES integration functions, it achieves seamless connection between quality inspection and production management. All inspection results, defect maps, and workpiece information are automatically uploaded to the MES system, providing a solid data foundation for product quality big data analysis, production process optimization, and full lifecycle traceability, greatly improving the efficiency and digitization level of quality management.

Claims

1. An automated ultrasonic testing device for differential welding components, characterized in that: include: An ultra-thin sheet-like ultrasonic probe is installed at an adjustable height below the weld seam of the differential welding assembly; An active jet coupling system forms a stable acoustic wave transmission medium layer between an ultrathin sheet-like ultrasonic probe and the weld. The ultrasonic analyzer and control unit are connected to the ultra-thin sheet-like ultrasonic probe to collect ultrasonic echo signals and perform real-time analysis using a perimeter algorithm to identify and quantify weld defects. When a defect echo exceeding a preset threshold is detected, the perimeter equivalent calculation is immediately initiated and all defects are automatically graded, outputting a final judgment on whether the weld is qualified. A mechanical scanning mechanism is used to clamp and drive the differential welding assembly to rotate; The data integration and communication module, which connects to the ultrasonic analyzer and control unit, is used to automatically generate test reports and upload test data to the manufacturing execution system; The alarm and execution unit is connected to the ultrasonic analyzer and control unit. It is used to trigger an alarm and output an interception signal when the final judgment is that the result is unqualified.

2. The automated ultrasonic testing equipment for differential welding components according to claim 1, characterized in that: The front end of the ultrathin sheet-like ultrasonic probe is a sheet-like structure no larger than 3mm, which contains a rectangular piezoelectric crystal.

3. An automated ultrasonic testing device for differential welding components according to claim 2, characterized in that: The piezoelectric wafer has a thickness of no more than 2 mm in the thickness direction of the ultrathin sheet-like ultrasonic probe and a length dimension of 5 mm to 3 mm.

4. An automated ultrasonic testing device for differential welding components according to claim 1, characterized in that: The ultrathin sheet-like ultrasonic probe operates at a frequency of 5MHz to 15MHz.

5. An automated ultrasonic testing device for differential welding components according to claim 1, characterized in that: The active jet coupling system includes an adjustable flow supply device and a nozzle located near an ultra-thin sheet-like ultrasonic probe. The nozzle is connected to the adjustable flow supply device, and the spray direction of the nozzle is adjustable.

6. An automated ultrasonic testing device for differential welding components according to claim 5, characterized in that: The adjustable flow supply device is a variable frequency water pump or a servo proportional valve, used to provide coupling fluid with an adjustable flow rate in the range of 0.5L / min to 2.0L / min.

7. An automated ultrasonic testing device for differential welding components according to claim 5, characterized in that: The spray direction of the nozzle forms an angle of 60° to 80° with the detection surface of the ultrathin sheet-like ultrasonic probe.

8. An automated ultrasonic testing device for differential welding components according to claim 1, characterized in that: The ultrasonic analyzer and control unit have the following built-in features: The weld defect evaluation module is used to execute a quantization algorithm based on defect perimeter equivalent to accurately quantify and rate common defects in welds. The automatic rating module is used to automatically compare the defect analysis results with the preset acceptance criteria and output a final judgment of whether the defect is qualified or unqualified.

9. An automated ultrasonic testing device for differential welding components according to claim 1, characterized in that: The mechanical scanning mechanism is a precision rotary table or a lathe-type chuck structure.

10. A testing method for an automated ultrasonic testing device for differential welding components according to any one of claims 1 to 9, comprising the following specific steps: S1, Fix the differential welding assembly to the mechanical scanning mechanism; S2, activate the active jet coupling system to spray coupling fluid between the fixedly installed ultra-thin sheet ultrasonic probe and the weld area to be inspected of the differential welding assembly to form a stable acoustic wave transmission medium layer; S3, the mechanical scanning mechanism drives the differential welding assembly to rotate, while the ultrasonic analyzer and control unit excite the ultra-thin sheet-like ultrasonic probe and collect ultrasonic echo signals; S4, the ultrasonic analyzer and control unit use the perimeter algorithm for real-time analysis, identify and quantify weld defects. When a defect echo exceeding the preset threshold is found, the perimeter equivalent calculation is immediately started and all defects are automatically graded, and the final judgment conclusion on whether it is qualified is output. S5 automatically generates inspection reports through the data integration and communication module, and uploads the inspection data and grading conclusions to the manufacturing execution system; S6, if the workpiece is deemed qualified, the production line is controlled to release it; if the workpiece is deemed unqualified, the alarm is triggered by the alarm and execution unit and a signal is output to intercept the differential welding assembly.

Images