Foamed board online detection method and device based on array type ultrasonic intelligent sensor

Abstract

The application relates to a foaming plate online detection method and device based on an array type ultrasonic intelligent sensor, and the method comprises the following steps: conveying the foaming plate to a detection station through a conveyor; controlling a telescopic electric cylinder to drive an ultrasonic probe to be close to the foaming plate and determining an initial detection interval; collecting ultrasonic signals and constructing an interval scoring function; controlling the telescopic electric cylinder to finely adjust the detection interval, and completing continuous online detection of the foaming plate under the best detection interval. The application realizes automatic optimization and dynamic maintenance of the best detection interval between the ultrasonic probe and the foaming plate by establishing an interval scoring mechanism based on detection signal quality, solves the problem that the fixed detection interval in the prior art is difficult to adapt to plate warping, thickness fluctuation and conveying vibration, and improves the stability, detection precision and automation level of the foaming plate online detection.

Description

Technical Field

[0001] This invention relates to the field of intelligent sensor technology, specifically to an online detection method and device for foamed boards based on an array-type ultrasonic intelligent sensor, which can be applied to the online quality inspection of foamed boards. Background Technology

[0002] Foamed panels for refrigerated containers are typically composed of a metal panel and a polyurethane foam insulation layer. The quality of the internal foaming directly affects the insulation performance, structural strength, and service life of the refrigerated container. During the foaming process, factors such as uneven distribution of the foaming agent, incomplete foaming reaction, poor interfacial adhesion, and fluctuations in the production process can easily lead to internal defects such as voids, delamination, layering, bubble aggregation, and localized low-density areas. Therefore, rapid and accurate online non-destructive testing of the internal quality of foamed panels during production is of great significance.

[0003] Currently, ultrasonic testing technology is widely used in the quality inspection of sandwich panels, composite materials, and foamed structures due to its ability to identify internal defects. Air-coupled ultrasonic testing uses a non-contact method to transmit and receive ultrasonic waves, eliminating the need for coupling agents. It can adapt to continuous production environments and offers advantages such as high testing efficiency and a high degree of automation. However, air-coupled ultrasonic signals experience significant attenuation in air, making its testing effectiveness highly sensitive to the air gap between the probe and the workpiece.

[0004] In existing technologies, such as CN114486625A, a method and system for detecting foaming defects in polyurethane sandwich insulation boards are disclosed. This method utilizes an air-coupled ultrasonic probe to detect the polyurethane sandwich insulation board. Ultrasonic signals are acquired by setting up transmitting and receiving probes, and a scanning mechanism is used to locate and identify foaming defects. In this technical solution, a preset detection distance is maintained between the air-coupled ultrasonic probe and the board being tested, and the probe scans along a set trajectory during the detection process to obtain information about internal defects in the board.

[0005] However, in actual production applications, it has been found that existing air-coupled ultrasonic testing systems typically use fixed or manually set testing intervals. When the foamed board experiences warping, thickness fluctuations, transport vibrations, or installation errors during transport, the actual air gap between the probe and the board surface will change. Because air-coupled ultrasonic signals are extremely sensitive to propagation distance, even small changes in distance can lead to significant attenuation of the received signal amplitude, decreased consistency between channels, and reduced testing stability, thereby affecting the accuracy of defect identification.

[0006] Especially on continuous production lines for foamed panels for refrigerated containers, the thickness of different batches of products varies, and different areas of the same panel may also exhibit localized warping and height fluctuations. When the detection system still uses a fixed-spacing detection method, it is often difficult to ensure that the air-coupled ultrasonic probe is always working in the optimal detection state, which can easily lead to false detections, missed detections, or large fluctuations in detection results.

[0007] Therefore, how to provide an air-coupled ultrasonic testing method and system that can automatically adjust the air gap between the probe and the foam plate according to the current detection signal quality and can continuously maintain the optimal detection distance during online testing has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0008] This invention aims to address the problems of fixed detection spacing and difficulty in adapting to changes in foam board thickness and surface warping in existing air-coupled ultrasonic testing technologies. This invention provides an online testing method and device for foam boards based on an array-type ultrasonic intelligent sensor.

[0009] In existing technologies, air-coupled ultrasonic probes are typically installed at a preset distance and maintained at a fixed detection interval during the testing process. However, due to variations in thickness, surface undulations, localized warping, and transport vibrations during the continuous production of refrigerated container foam panels, the actual air gap between the probe and the panel surface constantly changes. Since air-coupled ultrasonic waves experience significant attenuation in the air medium, their detection effectiveness is extremely sensitive to the air gap. Therefore, maintaining a fixed detection interval makes it difficult to ensure the probe always operates at its optimal detection state, easily leading to problems such as fluctuating detection signals, decreased defect identification accuracy, and false positives or false negatives.

[0010] To address this, the present invention proposes a dynamic optimization distance adjustment mechanism based on signal quality evaluation. By using a telescopic electric cylinder to adjust the detection distance between the air-coupled ultrasonic probe and the foam plate in real time, the probe is kept in the optimal coupling state, thereby improving the stability and accuracy of online detection.

[0011] To achieve the above objectives, the present invention adopts the following technical solution: An online detection method for foamed boards based on an array-type ultrasonic smart sensor, characterized by comprising the following steps: S1. The foam board is transported to the inspection station by the conveyor, and the foam board is identified and positioned. S2. Control the telescopic electric cylinder to drive the ultrasonic probe closer to the foam board, and determine the initial detection spacing according to the thickness parameters of the foam board and the preset detection parameters. S3. Acquire ultrasonic signals at the initial detection interval, extract the received signal amplitude of each probe channel and calculate the channel consistency parameter; S4. Normalize the received signal amplitude and channel consistency parameters respectively, establish a spacing scoring function based on the normalized parameters, and calculate the scoring value under different detection spacings. The spacing scoring function is used to characterize the coupling quality and detection stability between the ultrasonic probe and the foam plate. S5. Control the telescopic electric cylinder to fine-tune the distance between the ultrasonic probe and the foaming plate in a preset step size, compare the score values ​​corresponding to different detection distances, and determine the distance with the largest score value as the optimal detection distance. S6. Control the telescopic electric cylinder to maintain the optimal detection distance, so that the ultrasonic probe can continuously perform online detection on the foam board at the optimal detection distance; S7. During the detection process, if the score value corresponding to the current detection interval is lower than the preset threshold, control the telescopic electric cylinder to re-execute the fine-tuning scan to update the optimal detection interval. S8. Based on the changes in ultrasonic signals at each detection location, determine whether there are bonding defects, void defects, delamination defects, or bubble defects inside the foam board.

[0012] Preferably, the spacing scoring function in step S4 includes a normalized echo amplitude term and a normalized channel consistency term, and the two are fused with the same weight; Preferably, the fine-tuning scan in step S5 includes a coarse-tuning stage and a fine-tuning stage; In the coarse adjustment stage, the spacing is scanned using the first step length. In the fine adjustment stage, a second step length smaller than the first step length is used to scan near the spacing with the highest score, in order to lock in the optimal detection spacing.

[0013] Preferably, in step S7, when the score values ​​of multiple consecutive detection positions decrease, the telescopic electric cylinder is controlled to re-search for the optimal detection spacing in the opposite direction of the current adjustment direction.

[0014] Preferably, when a suspected defect area is detected, the telescopic electric cylinder is controlled to re-inspect the suspected defect area, and the fine-tuning scanning step size is reduced during the re-inspection process to determine the defect boundary range.

[0015] An online inspection device for foamed boards based on an array-type ultrasonic intelligent sensor, characterized in that it comprises: A conveyor is used to transport foamed boards to the testing station; Positioning and identification components are used to identify the location of the foam board. Telescopic electric cylinder is used to drive the ultrasonic probe to adjust the distance between the probe and the foaming plate; Ultrasonic probe, used for ultrasonic testing of foamed boards; The control system is communicatively connected to the conveyor, positioning and identification component, telescopic electric cylinder and ultrasonic probe, and is used to execute any of the above-described online detection methods for foamed boards.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention combines air-coupled ultrasonic testing with closed-loop distance control of a telescopic electric cylinder. Instead of using a fixed detection distance, it automatically finds the optimal detection distance based on the quality of the detection signal, fundamentally solving the problem of air-coupled ultrasonic testing being sensitive to distance changes.

[0017] This invention utilizes normalized echo amplitude and normalized channel consistency to construct a spacing scoring function, which can simultaneously take into account the detection signal strength and array channel stability, making the determination of the optimal detection spacing more in line with actual engineering needs.

[0018] This invention can adjust the probe position in real time according to changes in foam board thickness, board warping, and conveying vibration, so that the air-coupled ultrasonic probe always maintains the best coupling state, thereby improving the stability of the detection signal and the accuracy of defect identification.

[0019] This invention eliminates the need for repeated manual adjustment of the probe position, enabling continuous online inspection of foam board production lines, thereby improving the level of automation and production efficiency.

[0020] This invention is particularly suitable for large-scale online quality inspection of polyurethane foam insulation boards for refrigerated containers, and has good engineering application value and industrialization prospects. Attached Figure Description

[0021] Figure 1 This is a flowchart of an online detection method for foamed boards based on an array of ultrasonic smart sensors; Figure 2 This is a top view of the system structure of an online detection method for foamed boards based on an array of ultrasonic intelligent sensors; Figure 3 This is a side view of the system structure of an online detection method for foamed boards based on an array of ultrasonic intelligent sensors; Reference numerals: 1-Conveyor, 2-Positioning and identification component, 3-Telescopic electric cylinder, 4-Array-type ultrasonic probe mounting bracket. Detailed Implementation

[0022] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0023] like Figures 1-3As shown, this embodiment provides an online inspection method and device for foamed boards based on an array-type ultrasonic smart sensor. The object of inspection is a polyurethane foamed insulation board formed during the production of refrigerated containers. The foamed board typically includes an inner metal panel, an outer metal panel, and a polyurethane foam layer located between the two metal panels. The inspection targets mainly include defects such as voids within the foam layer, uneven foaming, interface debonding, delamination, and bubble aggregation.

[0024] The detection system used in this embodiment includes a conveyor 1, a positioning and identification component 2, a telescopic electric cylinder 3, an array of ultrasonic probes, and a control system. The array of ultrasonic probes includes multiple transmitting probes and multiple receiving probes arranged along the width of the foam board; the telescopic electric cylinder drives the array of ultrasonic probes to move in a direction perpendicular to the surface of the foam board; the control system adopts a PLC and industrial computer collaborative control architecture to realize conveyor control, ultrasonic signal acquisition, and distance optimization control.

[0025] The present invention adopts the following technical solution: An online detection method for foamed boards based on an array-type ultrasonic smart sensor, characterized by comprising the following steps: S1. The foam board is transported to the inspection station by the conveyor, and the foam board is identified and positioned.

[0026] In this embodiment, the foamed board enters the inspection and conveying section after being output from the production line. The conveyor preferably adopts a roller conveyor structure, with multiple powered rollers arranged sequentially along the conveying direction and driven by a variable frequency motor to achieve continuous conveying of the foamed board.

[0027] When the foam board enters the inspection area, a positioning and identification component, such as a photoelectric sensor, located at the entrance of the inspection station, first detects the leading edge position of the foam board. Once the photoelectric sensor detects that the board has entered the preset area, it sends a position signal to the control system.

[0028] After receiving the arrival signal, the control system calculates the current position of the foam board based on the conveying displacement information fed back by the conveyor encoder, and determines the position coordinates of the area to be detected by combining the foam board length parameter.

[0029] Preferably, a first laser displacement sensor is installed above the conveyor; a second laser displacement sensor is installed below the conveyor; these are used to detect the thickness of the foamed board. The thickness of the foamed board can be determined by averaging multiple measurements.

[0030] After completing the position calibration, the control system generates the current foam board inspection task information and stores the board number, size parameters, and production batch information into the inspection database to provide basic data for subsequent inspections.

[0031] S2. Control the telescopic electric cylinder to drive the ultrasonic probe closer to the foam board, and determine the initial detection spacing according to the thickness parameters of the foam board and the preset detection parameters.

[0032] Specifically, during ultrasonic testing, the air gap between the probe and the tested material directly affects the ultrasonic wave propagation loss and the received signal strength. Therefore, it is necessary to first determine a reasonable initial testing distance. S3. Acquire ultrasonic signals at the initial detection interval, extract the received signal amplitude of each probe channel, and calculate the channel consistency parameter.

[0033] S4. Normalize the received signal amplitude and channel consistency parameters respectively, establish a spacing scoring function based on the normalized parameters, and calculate the scoring value under different detection spacings. The spacing scoring function is used to characterize the coupling quality and detection stability between the ultrasonic probe and the foam plate.

[0034] Preferably, the spacing scoring function in step S4 includes a normalized echo amplitude term and a normalized channel consistency term, and the two are fused with the same weight; Since the effectiveness of air-coupled ultrasound detection is affected by both signal strength and channel consistency, this embodiment uses normalized echo amplitude and normalized channel consistency to jointly construct the spacing scoring function.

[0035] First, perform a distance scan within the preset adjustment range.

[0036] Specifically, the control system controls the telescopic electric cylinder to perform micro-step movements with a step length Δh.

[0037] Preferably: Δh = 0.5mm ~ 2mm.

[0038] The telescopic electric cylinder pauses its movement after each step and repeats step S3 to obtain the feature parameters A(h) and C(h) corresponding to the current detection interval.

[0039] All detection data obtained during the scanning process were normalized.

[0040] Because the echo amplitude range varies between different batches of products and under different testing conditions, the average echo amplitude is normalized. S5. Control the telescopic electric cylinder to fine-tune the distance between the ultrasonic probe and the foaming plate in a preset step size, compare the score values ​​corresponding to different detection distances, and determine the distance with the largest score value as the optimal detection distance.

[0041] Preferably, the fine-tuning scan in step S5 includes a coarse-tuning stage and a fine-tuning stage; In the coarse adjustment stage, the spacing is scanned using the first step length. In the fine adjustment stage, a second step length smaller than the first step length is used to scan near the spacing with the highest score, in order to lock in the optimal detection spacing.

[0042] S6. Control the telescopic electric cylinder to maintain the optimal detection distance, so that the ultrasonic probe can continuously perform online detection on the foam board at the optimal detection distance.

[0043]

[0044] During the continuous conveying of the foamed board, the air-coupled ultrasonic probe continuously acquires detection signals according to a preset sampling period and calculates the score corresponding to the current detection position in real time. Since the probe is working in the optimal acoustic coupling state at this time, it can obtain higher signal strength and better channel consistency, thereby improving the stability and accuracy of defect detection.

[0045] Meanwhile, the control system records the detection location, score, and ultrasonic test results in a correlated manner to form continuous detection data along the length of the foam board, providing basic data for subsequent defect identification and quality evaluation.

[0046] S7. During the detection process, if the score value corresponding to the current detection interval is lower than the preset threshold, control the telescopic electric cylinder to re-execute the fine-tuning scan to update the optimal detection interval.

[0047] Preferably, in step S7, when the score values ​​of multiple consecutive detection positions decrease, the telescopic electric cylinder is controlled to re-search for the optimal detection spacing in the opposite direction of the current adjustment direction.

[0048] During continuous online testing, the foam board may experience local warping, thickness fluctuations, or transport vibrations, which can cause changes in the actual distance between the air-coupled ultrasonic probe and the foam board, thereby reducing the quality of the detection signal.

[0049] Therefore, the control system monitors the score value corresponding to the current detection position in real time. When the current score value is lower than the preset threshold, it is considered that the current detection distance has deviated from the optimal working range. At this time, the control system re-executes the fine-tuning scanning process in step S5, searches for the detection position with the largest score value near the current detection distance, and updates it as the new optimal detection distance.

[0050] Preferably, the control system continuously records the trend of score changes at multiple detection positions. When the score values ​​at multiple consecutive detection positions show a downward trend, it indicates that the current adjustment direction may be causing the probe to gradually move away from the optimal coupling area.

[0051] At this point, the control system controls the telescopic electric cylinder to re-execute the distance search in the opposite direction of the current adjustment direction. For example, if the score value continues to decrease after the probe is adjusted towards the foam board, the telescopic electric cylinder is controlled to re-scan in the direction away from the foam board; conversely, if the score value continues to decrease after the probe is adjusted away from the foam board, the telescopic electric cylinder is controlled to re-scan in the direction towards the foam board.

[0052] Through the aforementioned dynamic compensation mechanism, the system can correct the probe position in real time according to the changes in the surface condition of the foam board, so that the air-coupled ultrasonic probe is always kept near the optimal detection distance, thereby ensuring signal quality and detection accuracy during the online detection process.

[0053] S8. Based on the changes in ultrasonic signals at each detection location, determine whether there are bonding defects, void defects, delamination defects, or bubble defects inside the foam board.

[0054] Preferably, when a suspected defect area is detected, the telescopic electric cylinder is controlled to re-inspect the suspected defect area, and the fine-tuning scanning step size is reduced during the re-inspection process to determine the defect boundary range.

[0055] After completing continuous online testing, the control system obtains ultrasonic testing data corresponding to each testing position of the foam board, including information such as echo amplitude, channel consistency parameters, and score values.

[0056] The control system continuously analyzes the detection data corresponding to each detection position according to the conveying direction of the foam board, and compares the detection result of the current detection position with the adjacent normal area.

[0057] When a certain detection area shows a significant decrease in echo amplitude, reduced channel consistency, or an abnormally reduced score, it indicates that the propagation state of ultrasound in that area has changed, and the control system identifies that area as a suspected abnormal area.

[0058] Furthermore, based on the attenuation level of the ultrasonic signal in the abnormal area, the abnormal distribution range, and the continuous change characteristics, the types of internal defects in the foam board are identified.

[0059] For example: When the overall echo amplitude in the detection area is significantly reduced and local areas are isolated, it can be determined as a foaming void defect. When signal attenuation occurs continuously at multiple adjacent detection locations within the detection area, it can be determined as an interface debonding defect or bonding defect. When a continuous abnormal area in the form of a band or sheet appears within the detection area, it can be identified as a layered defect. When multiple discretely distributed local abnormal areas appear within the detection area, it can be determined as a bubble aggregation defect.

[0060] The control system generates corresponding defect information based on the defect location, defect type, and degree of abnormality, and records it in the detection database.

[0061] Preferably, when a suspected defective area is detected, the control system initiates a re-inspection mode.

[0062] In re-inspection mode, the telescopic electric cylinder is controlled to move the air-coupled ultrasonic probe above the suspected defect area, and a local scan is re-executed with the optimal detection spacing corresponding to that area as the center.

[0063] Compared to the distance optimization process in step S5, the re-inspection process uses a smaller fine-tuning scanning step size for detection.

[0064] Preferably, the second step length in step S5 is 0.1 to 0.5 mm, while the scanning step length in the re-inspection process is further reduced to 0.05 to 0.2 mm.

[0065] The control system repeatedly acquires ultrasonic signals at multiple fine-tuning positions and compares the changes in the scoring values ​​and echo signals at each position to obtain more detailed detection results for suspected defect areas.

[0066] When the detection signal abruptly changes from a normal state to an abnormal state, the corresponding position is determined as the starting position of the defect boundary; when the detection signal recovers from an abnormal state to a normal state, the corresponding position is determined as the ending position of the defect boundary.

[0067] Based on the obtained defect boundary information, the control system calculates the defect length, defect width, and defect coverage area, and generates defect distribution results.

[0068] The above-mentioned re-inspection mechanism can further improve the accuracy of defect location and boundary identification, reduce the false detection rate and the missed detection rate, thereby improving the reliability of online inspection results of foamed boards.

[0069] An online inspection device for foamed boards based on an array-type ultrasonic intelligent sensor, characterized in that it comprises: A conveyor is used to transport foamed boards to the testing station; Positioning and identification components are used to identify the location of the foam board. Telescopic electric cylinder is used to drive the ultrasonic probe to adjust the distance between the probe and the foaming plate; Ultrasonic probe, used for ultrasonic testing of foamed boards; The control system is communicatively connected to the conveyor, positioning and identification component, telescopic electric cylinder and ultrasonic probe, and is used to execute the online detection method for foamed board as described in any one of claims 1-6.

[0070] Preferably, the ultrasonic probe includes multiple arrayed transmitting and / or receiving probes to cover multiple adjacent detection zones in a single detection.

[0071] Preferably, the control system includes an initial spacing setting unit, a scoring optimization unit, and a spacing holding unit; wherein, the initial spacing setting unit is used to determine the initial detection spacing based on the foam board thickness, conveying speed, and preset detection parameters; the scoring optimization unit is used to construct a spacing scoring function based on the acquired ultrasonic signals and control the telescopic electric cylinder to perform optimization; and the spacing holding unit is used to maintain the position of the ultrasonic probe at the optimal detection spacing.

[0072] Preferably, the system further includes a distance feedback component and a calibration unit; wherein, the distance feedback component is used to detect the actual distance between the ultrasonic probe and the foam plate in real time, and the calibration unit is used to perform distance calibration on the standard reference before detection begins, during detection intervals, or when detection is abnormal, and update the initial detection distance, the threshold of the distance scoring function, and / or fine-tune the scanning range accordingly.

[0073] Compared with the prior art, the present invention has the following beneficial effects: The present invention combines air-coupled ultrasonic detection with closed-loop distance adjustment control of telescopic electric cylinder, and no longer uses a fixed detection distance method, but automatically finds the optimal detection distance according to the quality of the detection signal, which fundamentally solves the problem of air-coupled ultrasonic detection being sensitive to distance changes.

[0074] This invention utilizes normalized echo amplitude and normalized channel consistency to construct a spacing scoring function, which can simultaneously take into account the detection signal strength and array channel stability, making the determination of the optimal detection spacing more in line with actual engineering needs.

[0075] This invention can adjust the probe position in real time according to changes in foam board thickness, board warping, and conveying vibration, so that the air-coupled ultrasonic probe always maintains the best coupling state, thereby improving the stability of the detection signal and the accuracy of defect identification.

[0076] This invention eliminates the need for repeated manual adjustment of the probe position, enabling continuous online inspection of foam board production lines, thereby improving the level of automation and production efficiency.

[0077] This invention is particularly suitable for large-scale online quality inspection of polyurethane foam insulation boards for refrigerated containers, and has good engineering application value and industrialization prospects.

Claims

1. A method for online detection of foamed boards based on an array-type ultrasonic intelligent sensor, characterized in that, Includes the following steps: S1. The foam board is transported to the inspection station by the conveyor, and the foam board is identified and positioned. S2. Control the telescopic electric cylinder to drive the ultrasonic probe closer to the foam board, and determine the initial detection spacing according to the thickness parameters of the foam board and the preset detection parameters. S3. Acquire ultrasonic signals at the initial detection interval, extract the received signal amplitude of each probe channel and calculate the channel consistency parameter; S4. Normalize the received signal amplitude and channel consistency parameters respectively, establish a spacing scoring function based on the normalized parameters, and calculate the scoring value under different detection spacings. The spacing scoring function is used to characterize the coupling quality and detection stability between the ultrasonic probe and the foam plate. S5. Control the telescopic electric cylinder to fine-tune the distance between the ultrasonic probe and the foaming plate in a preset step size, compare the score values ​​corresponding to different detection distances, and determine the distance with the largest score value as the optimal detection distance. S6. Control the telescopic electric cylinder to maintain the optimal detection distance, so that the ultrasonic probe can continuously perform online detection on the foam board at the optimal detection distance; S7. During the detection process, if the score value corresponding to the current detection interval is lower than the preset threshold, control the telescopic electric cylinder to re-execute the fine-tuning scan to update the optimal detection interval. S8. Based on the changes in ultrasonic signals at each detection location, determine whether there are bonding defects, void defects, delamination defects, or bubble defects inside the foam board.

2. The online detection method for foamed boards according to claim 1, characterized in that, The initial detection spacing in step S2 is determined by the thickness of the foam board and the center frequency of the ultrasonic probe.

3. The online detection method for foamed boards according to claim 1, characterized in that, The spacing scoring function in step S4 includes a normalized echo amplitude term and a normalized channel consistency term, and the two are fused with the same weight.

4. The online detection method for foamed boards according to claim 1, characterized in that, The fine-tuning scan in step S5 includes a coarse-tuning stage and a fine-tuning stage; In the coarse adjustment stage, the spacing is scanned using the first step length. In the fine adjustment stage, a second step length smaller than the first step length is used to scan near the spacing with the highest score, in order to lock in the optimal detection spacing.

5. The online testing method for foamed boards according to claim 1, characterized in that, In step S7, when the score values ​​of multiple consecutive detection positions decrease, the telescopic electric cylinder is controlled to search for the optimal detection spacing again in the opposite direction of the current adjustment direction.

6. The online detection method for foamed boards according to claim 1, characterized in that, When a suspected defect area is detected, the telescopic electric cylinder is controlled to re-inspect the suspected defect area, and the fine-tuning scanning step size is reduced during the re-inspection process to determine the defect boundary range.

7. An online inspection device for foamed boards based on an array-type ultrasonic intelligent sensor, characterized in that, include: A conveyor is used to transport foamed boards to the testing station; Positioning and identification components are used to identify the location of the foam board. Telescopic electric cylinder is used to drive the ultrasonic probe to adjust the distance between the probe and the foaming plate; Ultrasonic probe, used for ultrasonic testing of foamed boards; The control system is communicatively connected to the conveyor, positioning and identification component, telescopic electric cylinder and ultrasonic probe, and is used to execute the online detection method for foamed board as described in any one of claims 1-6.

8. The online testing device for foamed boards according to claim 7, characterized in that, The ultrasonic probe includes multiple arrayed transmitting and / or receiving probes to cover multiple adjacent detection zones in a single detection.

9. The online testing device for foamed boards according to claim 7, characterized in that, The control system includes an initial spacing setting unit, a scoring optimization unit, and a spacing maintenance unit; The initial spacing setting unit is used to determine the initial detection spacing based on the foam board thickness, conveying speed and preset detection parameters. The scoring optimization unit is used to construct a spacing scoring function based on the acquired ultrasonic signals and control the telescopic electric cylinder to perform optimization. The spacing holding unit is used to maintain the position of the ultrasonic probe at the optimal detection spacing.

10. The online testing device for foamed boards according to claim 7, characterized in that, The system also includes a distance feedback component and a calibration unit; The distance feedback component is used to detect the actual distance between the ultrasonic probe and the foam plate in real time. The calibration unit is used to perform distance calibration on the standard reference before the start of the test, during the test interval, or when the test is abnormal, and update the initial test distance, the threshold of the distance scoring function, and / or fine-tune the scanning range accordingly.

Images