Automatic electric leakage detection equipment and control method thereof

Abstract

The invention relates to automatic electric leakage detection equipment and a control method thereof, and relates to the technical field of electrical safety detection, and the automatic electric leakage detection equipment comprises a conveying structure used for conveying workpieces in sequence, a conduction structure used for electrifying heating parts in the workpieces, and a detection structure used for carrying out live detection on metal shells in the workpieces; the conveying structure is provided with an operation station which is convenient for synchronously electrifying and detecting a workpiece, the conduction structure comprises a conductive block which is in contact with the heating component, and the detection structure comprises a detection rod which is in contact with the metal shell; the conduction structure and the detection structure are installed on the conveying structure, and the conductive block and the detection rod are located on the operation station. The method has the effects of meeting the quality inspection requirements of large-scale production and improving the detection efficiency.

Description

Technical Field

[0001] This invention relates to the field of electrical safety detection technology, and in particular to an automated leakage current detection device and its control method. Background Technology

[0002] Electrical safety testing technology is a core technology branch that ensures the safety of electrical equipment, power systems, and personal and property safety. Its goal is to test key safety indicators of electrical equipment, such as insulation performance, leakage current, and grounding reliability.

[0003] There is a type of curling iron that includes a heat-resistant metal shell and a heating element embedded inside. The heating element is covered with an insulating layer to achieve electrical isolation. However, when the insulating layer is damaged, the heating element and the metal shell become conductive, causing the metal shell to become electrified, creating a leakage safety hazard. Current detection methods involve manually energizing the heating element and then using instruments to check whether the metal shell is electrified.

[0004] However, this testing method requires manual operation one by one, resulting in low testing efficiency and making it difficult to meet the quality inspection needs of large-scale production. Summary of the Invention

[0005] To meet the quality inspection needs of large-scale production and improve testing efficiency, this invention provides an automated leakage current detection device and its control method.

[0006] In a first aspect, the present invention provides an automated leakage current detection device, which adopts the following technical solution: An automated leakage current detection device includes a conveying structure for sequentially transporting workpieces, a conducting structure for energizing heating components in the workpieces, and a detection structure for detecting the electrical charge on the metal casing of the workpieces. The conveying structure has an operating station that facilitates simultaneous energization and testing of the workpiece; the conductive structure includes a conductive block that contacts the heating element; and the testing structure includes a testing rod that contacts the metal casing. The conductive structure and the detection structure are mounted on the conveying structure, and the conductive block and the detection rod are both located at the operating position.

[0007] By adopting the above technical solution, the workpiece to be tested is sequentially transported to the operating station by the conveying structure. The conductive block and the detection rod are simultaneously connected to the workpiece at the operating station, so as to realize the synchronous energization detection of the metal shell while the heating component is energized, achieving fully automated detection and improving detection efficiency.

[0008] Optionally, the conductive structure further includes a power supply component for providing high-voltage current to the conductive block and an adjustment plate for adjusting the position of the conductive block; The power supply component is electrically connected to the conductive block; The adjusting plate is slidably mounted on the conveying structure and connected to the conductive block.

[0009] By adopting the above technical solution, the adjusting plate is slidably installed on the conveying structure and connected to the conductive block. The spatial position of the conductive block can be adjusted by adjusting the adjusting plate, thereby adapting to workpieces of different specifications and sizes and improving the versatility of the equipment.

[0010] Optionally, the detection structure further includes a mounting base for mounting the detection rod, a tension spring for driving the detection rod to always have a tendency to conform to the workpiece, and a detection component for receiving and analyzing the data collected by the detection rod. The detection rod is electrically connected to the detection component; One end of the detection rod is rotatably connected to the mounting base, and the tension spring is fixedly installed between the detection rod and the mounting base.

[0011] By adopting the above technical solution, the elastic force of the tension spring in conjunction with the rotatable connection between the detection rod and the mounting base can drive the detection rod to always tend to fit against the workpiece, ensuring reliable contact between the detection rod and the metal shell of the workpiece, and avoiding the loss or error of detection data due to poor contact.

[0012] Secondly, this application provides a control method for an automated leakage current detection device, applied to an automated leakage current detection device as described in the first aspect, and adopts the following technical solution: A control method for an automated leakage current detection device includes: Step 10: In response to the detection signal, acquire the circuit breaker current and interval time, and continuously collect the resistance of the conductive block and the current of the detection rod; Step 11: Read the current of the detection rod based on the time interval and define it as the judgment current; Step 12: When the current is determined to be inconsistent with the circuit breaker current, acquire the acquisition time, moving speed and workpiece width; Step 13: Determine the number of bottom layers by combining the acquisition time, movement speed, and workpiece width; Step 14: Control the separation of the detection rod from the metal shell, read the resistance of the conductive block and define it as the detection resistance, and determine the number of workpieces by the detection resistance; Step 15: Determine the stacking shape by combining the current of the detection rod, the number of bottom layers, and the number of workpieces; Step 16: Determine the shaping parameters based on the stacking shape; Step 17: Shape the workpiece based on the shaping parameters and collect the shell resistance; Step 18: Determine the leakage current number by the casing resistance and reject it.

[0013] By adopting the above technical solution, the system determines whether there are multiple workpieces stacked in the operating station based on the resistance of the conductive block and the current of the detection rod. If there is stacking and leakage, the system identifies the stack shape and reshapes the workpieces into a single layer, re-identifies the specific workpieces with leakage and removes them, thereby improving the efficiency of leakage detection.

[0014] Optional methods for determining the stacking shape include: Step 20: Determine the current image based on the current of the detection rod; Step 21: Obtain the current peak value, number of peak values, and inter-peak interval from the current image; Step 22: Filter out the inter-peak intervals that are greater than the preset layer-switching threshold and use them as layer-switching nodes; Step 23: Divide the current image into several stable intervals based on the layer switching nodes; Step 24: Combine the number of workpieces and the number of bottom layers to set the stacking combination and obtain the corresponding number of outer workpieces; Step 25: Select stacked combinations where the number of outer workpieces matches the peak number and define them as target combinations; Step 26: Determine the stacking shape by combining the stable interval and the target combination.

[0015] By adopting the above technical solution, electrical signal features such as the number of peaks and the interval between peaks are extracted from the current image. The stable interval is divided by the layer-changing node. The electrical signal features are correlated with the number of vertical stacking layers. Then, the corresponding stacking shape is determined by combining all stacking combinations.

[0016] Optional methods for obtaining the number of peak values ​​include: Step 30: Obtain the coordinate nodes and their corresponding current amplitude and duration from the current image; Step 31: Determine the initial number of peak values ​​based on the current amplitude and its corresponding duration; Step 32: If the current amplitude is greater than the preset amplitude threshold and the duration is greater than the preset time threshold, define the corresponding coordinate node as a continuous leakage node. Step 33: Correct the current image by combining continuous leakage nodes; Step 34: Reacquire the number of peaks based on the corrected current image.

[0017] By adopting the above technical solution, continuous leakage nodes are determined by dual thresholds of current amplitude and duration, the interference of continuous leakage on the current image is identified, and the current image is corrected by combining the continuous leakage nodes, thereby obtaining the true number of peaks and avoiding the influence of leakage on the determination of the number of peaks.

[0018] Optionally, methods for correcting the current image include: Step 40: Read the no-load current from the current of the detection rod and extract the time nodes between consecutive leakage nodes and their corresponding current values; Step 41: Determine the current reference value based on the time node and its corresponding current value; Step 42: Determine the reference offset by combining the current reference value and the no-load current; Step 43: Correct the current value based on the reference offset; Step 44: Replace the current values ​​in the continuous leakage nodes in the current image with the corrected current values ​​to complete the correction of the current image.

[0019] By adopting the above technical solution, based on the no-load reference and combined with the current reference value between continuous leakage nodes, the reference offset value is determined, the current value affected by leakage interference is corrected, the true current value is restored, and thus the current image is corrected.

[0020] Optionally, methods for correcting layer-switching nodes include: Step 50: If the current amplitude is not greater than the amplitude threshold but is greater than the preset single contact threshold, define the corresponding current amplitude as the multi-contact current amplitude. Step 51: Calculate and determine the number of contacts based on the multi-contact current amplitude and the single-contact threshold. Step 52: Determine the new layer-switching nodes based on the number of contact points; Step 53: Correct the layer-switching nodes based on the newly added layer-switching nodes.

[0021] By adopting the above technical solution and combining the single contact threshold and amplitude threshold to screen the current amplitude, the abnormal situation of the detection rod contacting multiple workpieces at the same time can be accurately identified. Multiple workpieces will only be in contact at the same time when changing layers. The number of contacts can be calculated and determined by combining the multi-contact current amplitude and the single contact threshold, and the layer changing node can be corrected to avoid the loss of layer changing node and the incorrect division of stable interval due to multiple contacts.

[0022] Optionally, methods for determining the leakage current number include: Step 60: Collect the detection radius; Step 61: Determine the sampling interval based on the workpiece width, moving speed, and detection radius; Step 62: Sequentially assign workpiece numbers based on the number of workpieces; Step 63: Collect the casing resistance based on the acquisition interval and workpiece number; Step 64: Calculate the corresponding percentage coefficient by combining the workpiece number and its corresponding shell resistance; Step 65: Filter the corresponding workpiece number according to the proportion coefficient and define it as the leakage current number.

[0023] By adopting the above technical solution, the proportion coefficient is determined based on the shell resistance collected by the detection rod in contact with each workpiece. Based on the proportion coefficient, the influence value of each workpiece on the resistance in the circuit is judged. The larger the influence value, the more likely it is to be a workpiece with leakage, thereby specifically identifying the leakage number.

[0024] Optionally, the method for determining the leakage current number also includes: Step 70: Filter the proportion coefficients that are greater than the preset proportion threshold and define the corresponding shell resistance as the initial screening resistance; Step 71: Calculate the average resistance based on all the case resistances; Step 72: Calculate the resistance difference by combining the initial screening resistance and the average resistance; Step 73: Define the workpiece number corresponding to the resistance difference that is not greater than the preset difference threshold as the interference number and perform manual re-inspection; Step 74: Define the workpiece number corresponding to the resistance difference that is greater than the difference threshold as the leakage current number.

[0025] By adopting the above technical solution, the initial screening is performed using the proportion coefficient, and then a secondary screening is performed based on the difference threshold, which improves the accuracy of leakage current determination and effectively eliminates abnormal problems caused by non-leakage current factors such as contact vibration and electromagnetic interference.

[0026] In summary, the present invention has at least one of the following beneficial technical effects: The workpiece to be inspected is conveyed sequentially to the operating station by the conveying structure. The conductive block and the detection rod are simultaneously connected to the workpiece at the operating station, so that the heating component is energized while the metal shell is simultaneously energized for detection. This fully automated detection improves the detection efficiency. Based on the resistance of the conductive block and the current of the detection rod, it is determined whether there are multiple workpieces stacked in the operating station. In the case of stacking and leakage, the stacking shape is identified and the workpieces are reshaped into a single layer. The specific workpiece with leakage is re-identified and removed, which improves the leakage detection efficiency. The electrical signal features, such as the number of peaks and the interval between peaks, are extracted from the current image. The stable interval is divided by the layer-changing node. The electrical signal features are correlated with the number of vertical stacking layers. Then, the corresponding stacking shape is determined by combining all stacking combinations. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of an automated leakage current detection device according to this application. Figure 1 ; Figure 2 This is a schematic diagram of the structure of an automated leakage current detection device according to this application. Figure 2 ; Figure 3 yes Figure 2 Enlarged view of point A in the middle.

[0028] The parts referred to by the numbers in the above attached diagrams are as follows: 1. Conveying structure; 11. Belt conveyor; 12. Separator bar; 13. Operating station; 2. Conducting structure; 21. Conductive block; 22. Power supply component; 23. Adjusting plate; 3. Detection structure; 31. Support frame; 32. Detection rod; 33. Mounting base; 34. Tension spring; 35. Detection component. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0030] This invention discloses an automated leakage current detection device.

[0031] Reference Figure 1 and Figure 2 An automated leakage current detection device includes a conveying structure 1, a conducting structure 2, and a detection structure 3.

[0032] The conveying structure 1 includes a belt conveyor 11 and a separator 12, wherein the belt conveyor 11 is existing technology.

[0033] Multiple separator bars 12 are provided and evenly fixedly installed on the conveyor belt of the belt conveyor 11. The separator bars 12 move perpendicular to the conveying direction of the belt conveyor 11, and the cross-section of the separator bars 12 is triangular.

[0034] The belt conveyor 11 has an operating station 13 that facilitates the simultaneous energization and inspection of the workpiece.

[0035] Multiple workpieces are placed sequentially on the conveyor belt of the belt conveyor 11 and moved. The separator 12 corresponds to each workpiece. When the workpiece moves to the operating station 13, the conducting structure 2 contacts the heating component of the workpiece and energizes it. At the same time, the detection structure 3 contacts the metal shell of the workpiece and performs leakage detection.

[0036] The conductive structure 2 includes a conductive block 21, a power supply component 22, and an adjustment plate 23.

[0037] The conductive block 21 is fixedly installed on the adjusting plate 23, which is slidably installed on the frame of the belt conveyor 11. The adjusting plate 23 can be fixed to the belt conveyor 11 by bolts. The conductive block 21 is electrically connected to the power supply component 22.

[0038] The conductive block 21 is made of a highly conductive material, such as copper.

[0039] The power supply component 22 uses a high-voltage generator, which is existing technology.

[0040] According to the workpieces of different specifications and lengths, the control adjustment plate 23 slides along the frame of the belt conveyor 11. After sliding to the appropriate position, it is fixed by bolts. The adjustment plate 23 synchronously drives the conductive block 21 to move to ensure contact with the heating parts of the workpiece on the operating station 13. The power supply component 22 continuously provides high voltage current to the conductive block 21.

[0041] Reference Figure 1 , Figure 2 and Figure 3 The detection structure 3 includes a support frame 31, a detection rod 32, a mounting base 33, a tension spring 34, and a detection component 35.

[0042] The support frame 31 is fixedly installed on the frame of the belt conveyor 11, the mounting seat 33 is fixedly installed on the inner top of the support frame 31, one end of the detection rod 32 is rotatably connected to the mounting seat 33, the other end of the detection rod 32 is in contact with the workpiece on the operating station 13, the detection rod 32 is electrically connected to the detection assembly 35, and the tension spring 34 is fixedly installed between the detection rod 32 and the mounting seat 33.

[0043] The detection component 35 is fixedly installed on the upper end of the support frame 31. The detection component 35 adopts a leakage current tester, which is existing technology.

[0044] When the workpiece moves to the operating station 13, the tension spring 34 applies a force to the detection rod 32 in the opposite direction of the conveying direction, causing the detection rod 32 to always be in contact with the workpiece. Thus, the detection component 35 analyzes and judges the data collected on the detection rod 32 to realize leakage detection.

[0045] As the workpiece continues to move away from the operating station 13 following the belt conveyor 11, the workpiece pushes away the detection rod 32 and stretches the tension spring 34. When the workpiece is no longer in contact with the detection rod 32, the detection rod 32 resets under the force of the tension spring 34.

[0046] The partition bar 12 is set to support the workpiece to form a detection cycle, and at the same time can prevent the workpiece from moving away from its original position under the force of the detection rod 32.

[0047] Based on the same inventive concept, embodiments of the present invention provide a control method for an automated leakage current detection device.

[0048] A control method for an automated leakage current detection device includes the following steps: Step 10: In response to the detection signal, acquire the circuit breaker current and interval time, and continuously collect the resistance of the conductive block and the current of the detection rod.

[0049] The detection signal refers to the trigger signal used to trigger the system to start the detection process; after the photoelectric sensor installed on the belt conveyor 11 detects the workpiece, the system sends out the detection signal.

[0050] The circuit breaking current refers to the reference current value presented in the circuit where the detection rod 32 is located when the detection rod 32 is not in contact with the workpiece; when the detection rod 32 is completely separated from the workpiece and the circuit is in a stable no-load state, the current data collected by the detection component 35 is the circuit breaking current.

[0051] The interval time refers to the time interval at which the system reads the current data of the detection rod 32 in a regular manner; the distance between the two separator bars 12 on the belt conveyor 11 and the running speed are extracted from the system, and the result obtained by quotienting the distance between the separator bars 12 and the running speed is the interval time.

[0052] The resistance of the conductive block refers to the real-time resistance value of the conductive block 21 during the detection process; it is obtained by attaching a detection end of the detection component 35 to the conductive block 21 and continuously collecting data.

[0053] The current of the detection rod refers to the real-time current value of the detection rod 32 during the detection process; it is continuously acquired by the detection component 35.

[0054] Step 11: Read the current of the detection rod based on the interval time and define it as the judgment current.

[0055] The determination current refers to the current data at a specific time point extracted from the continuously collected detection rod current data based on the interval time. It represents the current data collected when the conductive block 21 comes into contact with the workpiece. The system reads the current from the detection rod according to the interval time after the detection rod 32 first touches the workpiece.

[0056] Step 12: When the current is determined to be inconsistent with the circuit breaker current, acquire the acquisition time, moving speed and workpiece width.

[0057] The discrepancy between the current and the circuit breaker current indicates that the detection rod 32 has come into contact with the metal shell of the workpiece and a current loop has been generated. This means that the metal shell is charged at this time, which corresponds to a leakage situation in the workpiece.

[0058] The acquisition time refers to the cumulative time from when the detection rod 32 contacts the leakage workpiece until it separates from the leakage workpiece; when the system determines that the current and the circuit current are inconsistent, it starts the built-in high-precision timing module until the determination ends and the timing stops. The data obtained at this time is the acquisition time.

[0059] The moving speed refers to the real-time linear speed of the belt conveyor 11; it is set by the operator when starting the belt conveyor 11 and the set data is stored in the system, and it is retrieved directly from the system.

[0060] The workpiece width refers to the reference width value of the workpiece in the vertical dimension along the running direction of the conveyor belt. The workpiece is pushed and conveyed by the separator 12. At this time, the workpiece width is the width dimension of the workpiece itself. The staff selects a workpiece sample in advance and measures the actual width dimension, and calculates the average value to obtain the workpiece width.

[0061] Step 13: Determine the number of bottom layers by combining the acquisition time, movement speed and workpiece width.

[0062] The bottom layer quantity refers to the number of workpieces arranged horizontally at the bottom layer when the workpieces are stacked on the belt conveyor 11; the calculation formula is: k=round((T×vr) / W)+1, where k is the bottom layer quantity, round is the rounding function, T is the collection time, v is the moving speed, r is the preset fixed distance, the fixed distance refers to the distance that a single workpiece moves from contacting the detection rod 32 to leaving the detection rod 32, and W is the workpiece width.

[0063] Step 14: Control the detection rod 32 to separate from the metal shell, read the resistance of the conductive block and define it as the detection resistance, and determine the number of workpieces by the detection resistance.

[0064] A robotic arm, pre-set near the operating station 13, grips and rotates the detection rod 32, causing the detection rod 32 to separate from the metal casing.

[0065] The detection resistance refers to the stable real-time resistance value of the conductive circuit where the conductive block 21 is located after the detection rod 32 is completely separated from the metal shell of the workpiece; the system reads the resistance value of the circuit where the conductive block 21 is located detected by the detection component 35, which is the detection resistance.

[0066] The number of workpieces refers to the total number of workpieces currently sent to the operating station 13 by the separator 12. At this time, the heating components of all workpieces are connected to the conductive block 21. The corresponding number of workpieces is found from the quantity correspondence table according to the detection resistance. The quantity correspondence table is a data table that records different detection resistances and their corresponding workpiece numbers. It is obtained by technicians through prior testing and will not be described in detail here.

[0067] When the heating element of the workpiece comes into contact with the conductive block 21, it is equivalent to connecting a resistor with a fixed parameter in parallel in the conductive circuit where the conductive block 21 is located. Therefore, the number of workpieces corresponds one-to-one with the detection resistor.

[0068] Step 15: Determine the stacking shape by combining the current of the detection rod, the number of bottom layers, and the number of workpieces.

[0069] The stacking shape refers to the specific combination of the number of vertical stacking layers of workpieces on the belt conveyor 11 and the number of workpieces arranged horizontally in each layer; the specific determination method will be disclosed in detail in subsequent steps, and will not be repeated here.

[0070] Step 16: Determine the shaping parameters based on the stacking shape.

[0071] Shaping parameters refer to a series of execution component parameters that regularize stacked workpieces into a single horizontal row with equal spacing. The corresponding shaping parameters are retrieved from the shaping correspondence table according to the stacking shape. The shaping correspondence table is a data table that records different stacking shapes and their corresponding shaping parameters. It is obtained by technicians through prior testing and will not be elaborated here.

[0072] Step 17: Shape the workpiece based on the shaping parameters and collect the shell resistance.

[0073] After the shaping is completed, the detection rod 32 is separated from the metal shell by the robotic arm, the belt conveyor 11 is controlled to run in the opposite direction, and the shaped workpieces are then passed through the operating station 13 in sequence.

[0074] The shell resistance refers to the resistance value collected when the detection rod 32 contacts all the shaped workpieces in sequence; the detection component 35 analyzes the data to obtain the shell resistance by contacting the workpiece shell with the detection rod 32 and collecting data.

[0075] Step 18: Determine the leakage current number by the casing resistance and reject it.

[0076] The leakage current number is a unique identifier for a workpiece that is determined to have a leakage current problem; the specific determination method will be disclosed in detail in subsequent steps, and will not be repeated here.

[0077] The method for determining the stacking shape includes the following steps: Step 20: Determine the current image based on the current of the detection rod.

[0078] A current image is a two-dimensional fluctuation image transformed using data visualization technology, with time as the horizontal axis and the current value of the detection rod as the vertical axis. Continuously collected detection rod current data is organized chronologically, and a built-in image generation algorithm converts the one-dimensional current data stream into a continuous current fluctuation curve, forming a visualized current image. The image generation algorithm can employ a combination of moving average filtering and linear interpolation fitting.

[0079] Step 21: Obtain the current peak value, number of peak values, and inter-peak interval from the current image.

[0080] The peak current refers to the sudden current change node presented in the current image, which represents the current data when the detection rod 32 comes into contact with the workpiece; the specific determination method will be disclosed in detail in subsequent steps, and will not be repeated here.

[0081] The number of peak values ​​refers to the total number of nodes in the current image that meet the characteristics of current peak values; the specific method for determining this will be disclosed in detail in subsequent steps and will not be repeated here.

[0082] The peak interval refers to the time difference between the start times of two adjacent current peaks in the current image, reflecting the time interval between the contact between the detection rod 32 and the two workpieces. The start time coordinates of each current peak are extracted from the current image by the image analysis algorithm, and the difference between the start times of two adjacent current peaks is calculated in chronological order, which is the peak interval.

[0083] Step 22: Filter the inter-peak intervals that are greater than the preset layer-switching threshold and use them as layer-switching nodes.

[0084] The layer-switching threshold is the critical value of the peak interval used to distinguish between "contact of workpieces stacked on the same layer" and "contact of workpieces stacked on different layers". The staff simulated the time required for the detection rod 32 to switch from the surface of two workpieces under different conditions through multiple experiments, and selected the median of the average layer-switching time and the average time without layer-switching as the layer-switching threshold. In this embodiment, the average layer-switching time is always greater than the average time without layer-switching.

[0085] Layer switching nodes refer to feature nodes in the current image that indicate the switching of the stacking layers of the workpiece. By traversing all the calculated inter-peak interval data through the algorithm, the inter-peak intervals with values ​​greater than the layer switching threshold are filtered out, and the next current peak node corresponding to the inter-peak interval is the layer switching node.

[0086] Step 23: Divide the current image into several stable intervals based on the layer switching nodes.

[0087] A stable interval refers to a continuous current fluctuation interval in the current image without any layer-switching nodes, with the layer-switching node as the dividing point. The current image is divided into several continuous current fluctuation intervals along the time axis by an image segmentation algorithm. The start time of each interval is the time coordinate of the previous layer-switching node, and the end time is the time coordinate of the next layer-switching node, which is the stable interval.

[0088] Step 24: Combine the number of workpieces and the number of bottom layers to set the stacking combination and obtain the corresponding number of outer workpieces.

[0089] Stacking combination refers to all possible combinations of vertical stacking layers and horizontal workpieces in each layer, generated according to the physical stability constraint of "wider at the bottom and narrower at the top". Using the number of workpieces and the number of bottom layers as input conditions, all possible stacking combinations are generated by exhaustive search.

[0090] Due to the limitations of the belt conveyor 11, in this embodiment, the maximum number of vertical stacking layers in the stacking combination is 3.

[0091] The number of outer workpieces refers to the number of outer workpieces that can contact the detection rod 32 for each generated stack combination. The number of workpieces that can contact the detection rod 32 when all stack combinations pass through the operation station 13 is calculated by experimental simulation and reading.

[0092] Step 25: Select stacked combinations where the number of outer workpieces matches the peak number and define them as target combinations.

[0093] The target combination refers to a stacked combination in which the number of outer workpieces is exactly the same as the number of peaks in the current image. The number of outer workpieces and the number of peaks corresponding to each stacked combination are compared one by one, and all stacked combinations in which the two are equal are selected, which are the target combinations.

[0094] Step 26: Determine the stacking shape by combining the stable interval and the target combination.

[0095] Stacking shape refers to the actual stacking distribution state of the corresponding workpieces on the belt conveyor 11. If there is only one target combination that meets the conditions, its corresponding shape is directly defined as the stacking shape. If there are multiple target combinations, the vertical layer number and the number of stable intervals of each target combination are further compared. The combination that matches the two is taken as the unique target combination, and its corresponding shape is defined as the stacking shape.

[0096] The stacking combinations and stacking shapes are set to correspond one-to-one. The corresponding stacking shape is retrieved from the stacking correspondence table based on the target combination or the unique target combination. The stacking correspondence table is a data table that records different stacking combinations and their corresponding stacking shapes. It is obtained by technicians through pre-testing and will not be described in detail here.

[0097] The method for obtaining the number of peak values ​​includes the following steps: Step 30: Obtain the coordinate nodes and their corresponding current amplitude and duration from the current image.

[0098] Coordinate nodes are two-dimensional coordinate points in a current image where the current value changes abruptly. By scanning the current image point by point using an edge detection algorithm, abrupt points where the current value suddenly rises or falls from a stable state are identified, i.e., coordinate nodes.

[0099] Current amplitude refers to the current value corresponding to the coordinate node, that is, the stable current value reached after a sudden change in current. When the coordinate node is generated, its corresponding current value is automatically stored in the system and can be directly read when needed.

[0100] Duration refers to the duration for which the current amplitude remains at the value after the abrupt change. The start and end times of the current abrupt change corresponding to each coordinate node are identified from the current image, and the difference between the two time points is calculated, which is the duration.

[0101] Step 31: Determine the number of initial peak values ​​based on the current amplitude and its corresponding duration.

[0102] The initial peak count refers to the total number of coordinate nodes in the current image that meet the characteristics of current peaks. All coordinate nodes are screened one by one, and the total number of nodes that meet the characteristics of current peaks is defined as the initial peak count.

[0103] In this embodiment, the current peak characteristic refers to the current amplitude being between 0.8 times and 1.2 times the standard current value, and the duration being between 0.5 times and 1.5 times the single workpiece passing time. The standard current value refers to the current value collected when a qualified workpiece contacts the detection rod 32. The single workpiece passing time refers to the time from when a single workpiece contacts the detection rod 32 to when it leaves the detection rod 32. Both are preset by the staff and stored in the system, and can be directly retrieved when needed.

[0104] If the current amplitude exceeds 1.2 times the standard current value but the duration is between 0.5 times and 1.5 times the single workpiece passing time, it means that only the workpiece at this point is leaking current, and there is no continuous leakage. This will not affect the one-to-one correspondence between the peak value and the workpiece. Therefore, its quantity can also be used as the initial peak value quantity.

[0105] When multiple workpieces are stacked, their metal shells come into contact with each other. If there is a workpiece with leakage current, it will cause the metal shells of all stacked workpieces to become charged. The surface current of qualified workpieces is weak, while the surface current of workpieces with leakage current is strong. If there are consecutive workpieces with leakage current, it is difficult to determine the peak position of the corresponding workpiece in the current image, thus affecting the determination relationship between the peak value and the workpiece.

[0106] Step 32: If the current amplitude is greater than the preset amplitude threshold and the duration is greater than the preset time threshold, define the corresponding coordinate node as a continuous leakage node.

[0107] The amplitude threshold refers to the maximum current amplitude that meets the current peak characteristics as explained in the above steps; it is preset by the staff and stored in the system, and can be retrieved directly when needed.

[0108] The time threshold refers to the maximum duration for which the current peak characteristics are met as explained in the above steps; it is preset by staff and stored in the system, and can be retrieved directly when needed.

[0109] A continuous leakage node refers to the initial node and the end node corresponding to the interval where both the current amplitude and duration exceed the threshold. When the current amplitude exceeds the threshold, the corresponding coordinate node is marked as the expected initial node. If the duration of the subsequent determination also exceeds the threshold, the coordinate node where the current change occurs next is marked as the end node, and the corresponding expected initial node is the initial node, thus obtaining the continuous leakage node.

[0110] If the current amplitude is greater than the amplitude threshold, it indicates that the corresponding workpiece is a leakage workpiece, and if the duration is greater than the time threshold, it indicates that the leakage workpiece appears continuously.

[0111] Step 33: Correct the current image by combining continuous leakage nodes.

[0112] The current image is corrected based on continuous leakage nodes. The specific correction method will be disclosed in detail in subsequent steps and will not be repeated here.

[0113] Step 34: Reacquire the number of peaks based on the corrected current image.

[0114] The method for obtaining the number of peak values ​​here is the same as the method for obtaining the initial number of peak values ​​mentioned earlier, and will not be repeated here.

[0115] The method for correcting current images includes the following steps: Step 40: Read the no-load current from the current of the detection rod and extract the time nodes and their corresponding current values ​​between consecutive leakage nodes.

[0116] The no-load current refers to the current value in the circuit where the detection rod 32 is located when the detection rod 32 is completely separated from the metal shell of the workpiece. After the detection rod 32 is completely separated from the metal shell of the workpiece, the system delays for 50 milliseconds before reading the current value in the circuit where the conductive block 21 is located, which is the no-load current.

[0117] A time node refers to the time coordinate in the two-dimensional coordinate system between the initial node and the end node of a continuous leakage current node; the time coordinates between continuous leakage current nodes are directly extracted from the current image, i.e., the time node.

[0118] The current value refers to the current data that corresponds one-to-one with the time node; it is accurately extracted directly from the corresponding time node in the current image.

[0119] Step 41: Determine the current reference value based on the time node and its corresponding current value.

[0120] The current reference value is the arithmetic mean of all current values ​​between consecutive leakage nodes; the average value of all time nodes and their corresponding current values ​​is calculated using the arithmetic mean formula, which is the current reference value.

[0121] Step 42: Determine the reference offset by combining the current reference value and the no-load current.

[0122] The reference offset is a quantitative value of the degree to which leakage interference affects the normal circuit condition; it is obtained by calculating the difference between the current reference value and the no-load current.

[0123] Step 43: Correct the current value based on the reference offset.

[0124] The corrected current value is obtained by subtracting the current value between consecutive leakage nodes from the reference offset value.

[0125] Step 44: Replace the current values ​​in the continuous leakage nodes in the current image with the corrected current values ​​to complete the correction of the current image.

[0126] The corrected current value eliminates leakage interference and restores the true characteristics of the current signal. The corrected current value replaces the original current value to regenerate the current image, thus completing the correction of the current image.

[0127] The method for correcting layer-switching nodes includes the following steps: Step 50: If the current amplitude is not greater than the amplitude threshold but is greater than the preset single contact threshold, define the corresponding current amplitude as the multi-contact current amplitude.

[0128] The single contact threshold refers to the critical value of the current amplitude used to distinguish between the simultaneous contact of the detection rod 32 with a single workpiece and multiple workpieces. The contact reference current when a qualified workpiece in contact with a leaking workpiece is individually contacted by the detection rod 32 is determined by experiment. 1.1 times the contact reference current is used as the single contact threshold, which is obtained in advance by the staff and stored in the system.

[0129] If the current amplitude is not greater than the amplitude threshold but is greater than the single contact threshold, it means that the detection rod 32 is in contact with multiple workpieces at the same time and none of these workpieces are leaking current.

[0130] The multi-contact current amplitude refers to the specific current amplitude value corresponding to the coordinate node between the single-contact threshold and the amplitude threshold. Since the detection rod 32 is in contact with multiple workpieces at the same time, the detection circuit exhibits different current amplitudes due to load changes. The magnitude of the current amplitude is positively correlated with the number of workpieces that the detection rod 32 is in contact with at the same time. The current amplitude at this time is directly read, which is the multi-contact current amplitude.

[0131] Step 51: Calculate and determine the number of contacts based on the multi-contact current amplitude and the single-contact threshold.

[0132] The number of contacts refers to the actual number of workpieces that the detection rod 32 contacts simultaneously. The multi-contact current amplitude is calculated by dividing the single-contact threshold by the multi-contact current amplitude, and the result is rounded to the nearest integer to obtain a positive integer, which is the number of contacts.

[0133] Step 52: Determine the new layer replacement node based on the number of contact points.

[0134] Adding a new layer-change node refers to inserting a virtual layer-change node at equal time intervals within the duration of the coordinate node based on the number of touch points; the number of virtual layer-change nodes is obtained by subtracting 1 from the number of touch points, and the corresponding number of virtual layer-change nodes are inserted into the duration of the node.

[0135] For example, if a certain coordinate node has three contact points, that is, it is in contact with three workpieces at the same time, based on the actual situation, it is possible that the edges of the three workpieces are on a line. That is, inserting two layer-changing nodes at this coordinate node indicates that two layer-changing situations have occurred consecutively here.

[0136] Step 53: Correct the layer-switching nodes based on the newly added layer-switching nodes.

[0137] The newly added layer-changing node is integrated with the original layer-changing node to obtain the corrected layer-changing node.

[0138] The method for determining the leakage current number includes the following steps: Step 60: Collect the detection radius.

[0139] The detection radius refers to the effective rotation radius of the detection rod 32; the straight-line distance between the contact point between the detection rod 32 and the workpiece and the rotation axis is measured in advance by the staff and stored in the system in advance.

[0140] Step 61: Determine the sampling interval based on the workpiece width, moving speed, and detection radius.

[0141] The acquisition interval refers to the time interval between the detection rod 32 contacting the outer shell of two adjacent workpieces in sequence. Based on the workpiece width, moving speed and detection radius, multiple experiments are conducted and the actual interval is collected. The average value of the multiple collected data is then used as the acquisition interval.

[0142] Step 62: Set the workpiece number sequentially according to the number of workpieces.

[0143] The workpiece number refers to a unique numerical sequential identifier assigned to each workpiece according to the order in which the workpieces pass through the operating station on the conveyor belt 11; based on the number of workpieces, a unique numerical identifier is assigned to each workpiece sequentially in ascending order of positive integers, starting from 1, and the total number of workpiece numbers is consistent with the number of workpieces.

[0144] Step 63: Collect the casing resistance based on the acquisition interval and workpiece number.

[0145] The casing resistance is collected sequentially based on the acquisition interval, and the casing resistance is matched one by one with the workpiece number.

[0146] Step 64: Calculate the corresponding percentage coefficient by combining the workpiece number and its corresponding shell resistance.

[0147] The proportion factor refers to the ratio of the shell resistance of a single workpiece to the sum of the shell resistances of all workpieces in the current batch of inspection, reflecting the influence of a single workpiece on the overall resistance. First, the total resistance value is calculated by summing all the statistical shell resistances. Then, the proportion factor is calculated by dividing each shell resistance by the total resistance value.

[0148] Step 65: Filter the corresponding workpiece number according to the proportion coefficient and define it as the leakage current number.

[0149] The leakage current number refers to the workpiece number corresponding to the workpiece with leakage current; the specific determination method will be disclosed in detail in subsequent steps, and will not be repeated here.

[0150] The method for determining the leakage current number also includes the following steps: Step 70: Filter the percentage coefficients that are greater than the preset percentage threshold and define the corresponding shell resistance as the initial screening resistance.

[0151] The percentage threshold is the criterion for distinguishing whether the percentage coefficient of the workpiece shell resistance is within the normal range or the abnormal range. The shell resistance data of qualified workpieces of the same type are collected in advance, and the percentage coefficient of all qualified workpieces is obtained according to the percentage coefficient calculation formula. 95% of the average percentage coefficient is used as the percentage threshold, which is obtained in advance by the staff and stored in the system.

[0152] The initial screening resistance refers to the casing resistance of workpieces suspected of leakage after removing qualified workpieces with normal proportion coefficients; all proportion coefficients are compared with the proportion threshold in turn, and the proportion coefficients that are greater than the proportion threshold are selected and their corresponding casing resistances are defined as the initial screening resistance.

[0153] Step 71: Calculate the average resistance based on all the case resistances.

[0154] Average resistance refers to the benchmark value of the overall resistance level of the casing of the workpiece in the current batch of inspection; the average resistance is calculated by the arithmetic mean formula for all casing resistances.

[0155] Step 72: Calculate the resistance difference by combining the initial screening resistance and the average resistance.

[0156] The resistance difference refers to the numerical value that quantifies the degree to which the resistance of a single initial screening unit deviates from the overall resistance level of the current batch of workpieces being inspected; the resistance difference is obtained by subtracting the initial screening resistance from the average resistance and calculating the average value.

[0157] Step 73: Define the workpiece number corresponding to the resistance difference that is not greater than the preset difference threshold as the interference number and perform manual re-inspection.

[0158] The difference threshold is the critical value of the resistance difference used to distinguish between workpieces with leakage current and abnormal workpieces caused by detection interference. By collecting a large number of shell resistance data corresponding to the contact of qualified workpieces and workpieces with leakage current through experiments, the minimum difference between the average resistance of workpieces with leakage current and qualified workpieces is calculated as the difference threshold, which is obtained in advance and stored in the system.

[0159] Interference number refers to the workpiece number corresponding to the initial screening resistor whose resistance difference is not greater than the difference threshold. The resistance difference corresponding to each initial screening resistor is compared with the difference threshold one by one, and the resistance difference that is not greater than the difference threshold is selected and the corresponding workpiece number is defined as the interference number.

[0160] It is difficult to determine whether the workpiece corresponding to the interference number has leakage, and further manual re-inspection is required.

[0161] Step 74: Define the workpiece number corresponding to the resistance difference that is greater than the difference threshold as the leakage current number.

[0162] A resistance difference greater than the difference threshold indicates that the corresponding workpiece is definitely in a leakage condition. The corresponding workpiece number is defined as the leakage number and is then rejected.

[0163] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. An automated leakage current detection device, characterized in that, It includes a conveying structure (1) for transporting workpieces sequentially, a conducting structure (2) for energizing the heating components in the workpiece, and a detection structure (3) for detecting the electrical charge on the metal shell of the workpiece. The conveying structure (1) has an operating station (13) that facilitates the simultaneous energization and detection of the workpiece. The conductive structure (2) includes a conductive block (21) that contacts the heating element. The detection structure (3) includes a detection rod (32) that contacts the metal casing. The conductive structure (2) and the detection structure (3) are installed on the conveying structure (1), and the conductive block (21) and the detection rod (32) are both located on the operating station (13).

2. The automated leakage current detection device according to claim 1, characterized in that, The conductive structure (2) also includes a power supply component (22) for providing high voltage current to the conductive block (21) and an adjustment plate (23) for adjusting the position of the conductive block (21). The power supply component (22) is electrically connected to the conductive block (21); The adjusting plate (23) is slidably mounted on the conveying structure (1) and connected to the conductive block (21).

3. The automated leakage current detection device according to claim 1, characterized in that, The detection structure (3) further includes a mounting base (33) for mounting the detection rod (32), a tension spring (34) for driving the detection rod (32) to always have a tendency to fit the workpiece, and a detection component (35) for receiving and analyzing the data collected by the detection rod (32). The detection rod (32) is electrically connected to the detection component (35); One end of the detection rod (32) is rotatably connected to the mounting base (33), and the tension spring (34) is fixedly installed between the detection rod (32) and the mounting base (33).

4. A control method for an automated leakage current detection device, applied to an automated leakage current detection device as described in any one of claims 1 to 3, characterized in that, include: Step 10: In response to the detection signal, acquire the circuit breaker current and interval time, and continuously collect the resistance of the conductive block and the current of the detection rod; Step 11: Read the current of the detection rod based on the time interval and define it as the judgment current; Step 12: When the current is determined to be inconsistent with the circuit breaker current, acquire the acquisition time, moving speed and workpiece width; Step 13: Determine the number of bottom layers by combining the acquisition time, movement speed, and workpiece width; Step 14: Control the detection rod (32) to separate from the metal shell, read the resistance of the conductive block and define it as the detection resistance, and determine the number of workpieces by the detection resistance; Step 15: Determine the stacking shape by combining the current of the detection rod, the number of bottom layers, and the number of workpieces; Step 16: Determine the shaping parameters based on the stacking shape; Step 17: Shape the workpiece based on the shaping parameters and collect the shell resistance; Step 18: Determine the leakage current number by the casing resistance and reject it.

5. The control method for an automated leakage current detection device according to claim 4, characterized in that, Methods for determining the stacking shape include: Step 20: Determine the current image based on the current of the detection rod; Step 21: Obtain the current peak value, number of peak values, and inter-peak interval from the current image; Step 22: Filter out the inter-peak intervals that are greater than the preset layer-switching threshold and use them as layer-switching nodes; Step 23: Divide the current image into several stable intervals based on the layer switching nodes; Step 24: Combine the number of workpieces and the number of bottom layers to set the stacking combination and obtain the corresponding number of outer workpieces; Step 25: Select stacked combinations where the number of outer workpieces matches the peak number and define them as target combinations; Step 26: Determine the stacking shape by combining the stable interval and the target combination.

6. The control method for an automated leakage current detection device according to claim 5, characterized in that, Methods for obtaining the number of peak values ​​include: Step 30: Obtain the coordinate nodes and their corresponding current amplitude and duration from the current image; Step 31: Determine the initial number of peak values ​​based on the current amplitude and its corresponding duration; Step 32: If the current amplitude is greater than the preset amplitude threshold and the duration is greater than the preset time threshold, define the corresponding coordinate node as a continuous leakage node. Step 33: Correct the current image by combining continuous leakage nodes; Step 34: Reacquire the number of peaks based on the corrected current image.

7. The control method for an automated leakage current detection device according to claim 6, characterized in that, Methods for correcting current images include: Step 40: Read the no-load current from the current of the detection rod and extract the time nodes between consecutive leakage nodes and their corresponding current values; Step 41: Determine the current reference value based on the time node and its corresponding current value; Step 42: Determine the reference offset by combining the current reference value and the no-load current; Step 43: Correct the current value based on the reference offset; Step 44: Replace the current values ​​in the continuous leakage nodes in the current image with the corrected current values ​​to complete the correction of the current image.

8. The control method for an automated leakage current detection device according to claim 7, characterized in that, The correction methods for layer-switching nodes include: Step 50: If the current amplitude is not greater than the amplitude threshold but is greater than the preset single contact threshold, define the corresponding current amplitude as the multi-contact current amplitude. Step 51: Calculate and determine the number of contacts based on the multi-contact current amplitude and the single-contact threshold. Step 52: Determine the new layer-switching nodes based on the number of contact points; Step 53: Correct the layer-switching nodes based on the newly added layer-switching nodes.

9. The control method for an automated leakage current detection device according to claim 4, characterized in that, The methods for determining the leakage current number include: Step 60: Collect the detection radius; Step 61: Determine the sampling interval based on the workpiece width, moving speed, and detection radius; Step 62: Sequentially assign workpiece numbers based on the number of workpieces; Step 63: Collect the casing resistance based on the acquisition interval and workpiece number; Step 64: Calculate the corresponding percentage coefficient by combining the workpiece number and its corresponding shell resistance; Step 65: Filter the corresponding workpiece number according to the proportion coefficient and define it as the leakage current number.

10. The control method for an automated leakage current detection device according to claim 9, characterized in that, Methods for determining leakage current numbers also include: Step 70: Filter the proportion coefficients that are greater than the preset proportion threshold and define the corresponding shell resistance as the initial screening resistance; Step 71: Calculate the average resistance based on all the case resistances; Step 72: Calculate the resistance difference by combining the initial screening resistance and the average resistance; Step 73: Define the workpiece number corresponding to the resistance difference that is not greater than the preset difference threshold as the interference number and perform manual re-inspection; Step 74: Define the workpiece number corresponding to the resistance difference that is greater than the difference threshold as the leakage current number.

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