Steel cord detection rapid correction method and steel cord detection device

Abstract

The application provides a steel cord detection rapid correction method and a steel cord detection device. The rapid correction method is used for rapidly correcting the steel cord detection device and comprises the following steps: S100: determining the effective detection row number L based on the period number T, the steel cord detection device parameter information and the steel cord parameter information; S200: scanning the steel cord moving along the sub-scanning direction by the steel cord detection device; S300: performing effectiveness detection on the original scanning data obtained by scanning, determining at least one group of effective data passing the effectiveness detection from the original scanning data, and generating correction data based on the effective data, wherein the effective data comprises L rows of original scanning data; and S400: correcting the steel cord detection device by using the correction data. The technical scheme of the application can rapidly and accurately correct the steel cord detection device in the case that the steel cord detection device is in the normal detection state of the magnetic field.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of industrial nondestructive testing, in particular to the nondestructive testing technology of steel cord, and specifically provides a steel cord detection rapid correction method and a steel cord detection device. BACKGROUND

[0002] The steel cord is an industrial raw material with steel cord arranged at equal intervals inside and a wear-resistant layer (generally rubber or other materials) wrapped outside, which can be used to manufacture various load-bearing tires, conveyor belts, transportation pipelines and other products. In order to ensure the quality of the steel cord, the steel cord used as a framework and support is generally detected for defects during its production process.

[0003] At present, there are many devices and methods for real-time nondestructive testing of steel cord during its production process. Among them, the nondestructive testing method based on electromagnetic induction principle detects the steel cord inside the steel cord according to the change of the magnetic field caused by the movement of the steel cord in the magnetic field, which has the characteristics of economy, safety and convenience.

[0004] For the device for detecting the steel cord by using electromagnetic induction, the consistency accuracy of the magnetic sensor module for acquiring the magnetic signal of the front-end steel cord and each magnetic sensitive element contained therein will directly affect the accuracy of the generated magnetic image, so it is necessary to correct it. In order to achieve good correction effect, some online calibration methods used in existing steel cord detection devices based on magnetic field make the steel cord in a static state or make it away from the detection part through the design of some movement structure to reduce the influence on the magnetic sensitive element. When using the above correction method to correct the steel cord detection device, the following problems exist:

[0005] (1) The above correction method often needs to be carried out in a standard correction environment, and the steel cord is made away from the detection surface or removed from the detection device through the design of structure to avoid its interference with the magnetic sensitive element. However, through the analysis of the reasons for the error of the magnetic sensitive element, it is found that one of the important reasons for the error of the magnetic sensitive element is the mutual coupling between the steel cord and the excitation magnetic field in the normal scanning state, and the error caused by this reason will be continuously accumulated and amplified with the normal scanning, in addition, the parameters such as environment / product temperature are different from those in the static state during the continuous movement of the steel cord, therefore, the correction of the magnetic sensitive element contained in the magnetic sensor module when the steel cord is away from the detection device or in the static state cannot truly reflect the continuously changing magnetic field and environment in the normal detection, thus leading to poor correction effect.

[0006] (2) The above correction methods all need to design additional linkage structures, which are large in size and complex in structure, and after each correction, repositioning operation is needed, which undoubtedly increases the production cost and reduces the work efficiency. SUMMARY

[0007] The present application aims to solve the problems existing in the prior art, and provides a method for quickly correcting a steel cord detection device in the case of a normal detection state of the magnetic field of the steel cord detection device, and a steel cord detection using the method.

[0008] One aspect of the present application provides a method for quickly correcting a steel cord detection device, which includes the following steps:

[0009] S100: determining the number of effective detection rows L based on the period number T, the parameter information of the steel cord detection device, and the parameter information of the steel cord;

[0010] S200: scanning the steel cord moving along the sub-scanning direction by the steel cord detection device;

[0011] S300: performing effectiveness detection on the original scan data obtained by scanning, determining at least one group of effective data passing the effectiveness detection from the original scan data, and generating correction data based on the effective data, wherein the effective data contains L rows of original scan data;

[0012] S400: correcting the steel cord detection device using the correction data.

[0013] Further, the original scan data is the magnetic field intensity value obtained by scanning by the steel cord detection device when the steel cord moves.

[0014] Preferably, the period number T is an integer greater than or equal to 2.

[0015] Further, L is determined based on the following formula:

[0016] L = T * G * R / 25.4,

[0017] wherein G is the pitch of the steel cord in the steel cord along the sub-scanning direction, in mm, and R is the resolution of the magnetic sensor module included in the steel cord detection device, in DPI.

[0018] Further, each row of original scan data contains N magnetic field intensity values V0(j), j = 1, 2, …, N obtained along the scanning direction, wherein N is the number of magnetic sensitive elements included in the magnetic sensor module along the scanning direction; the scanning direction is perpendicular to the sub-scanning direction and parallel to the width of the steel cord.

[0019] Further, the validity detection in step S300 comprises the following steps:

[0020] S310: Extracting a group of L rows of original scanning data V0(i,j), i=1, 2, …, L, j=1, 2, …, N;

[0021] S320: Calculating the average value Ave V of each period of original scanning data based on the following formula: k

[0022]

[0023] S330: Comparing Ave V k pair by pair, and calculating the difference between any two Ave V k ;

[0024] S340: Determining whether the difference between any two Ave V k exceeds a preset threshold value, if the determination result is yes, executing step S350, otherwise executing step S360;

[0025] S350: Storing the group of L rows of original scanning data as invalid data V n (i,j), i=1, 2, …, L, j=1, 2, …, N, and returning to step S310;

[0026] S360: Storing the group of L rows of original scanning data as valid data V e (i,j), i=1, 2, …, L, j=1, 2, …, N which passes the validity detection, and ending the validity detection.

[0027] Further, the correction data is determined based on the following formula:

[0028]

[0029] Wherein, V is a preset correction reference value.

[0030] Further, step S400 comprises the following steps:

[0031] S410: Scanning the steel cord moving along the sub-scanning direction by the steel cord detection device and acquiring a plurality of rows of normal scanning data, wherein each row of normal scanning data contains N magnetic field strength values V(j), j=1, 2, …, N acquired along the scanning direction;

[0032] S420: Determining each row of corrected scanning data by the following formula:

[0033] EV(j)=V(j)+K(j), j=1, 2, …, N.

[0034] ​Preferably, the step S400 further comprises correcting the plurality of rows of original scanning data using the correction data.

[0035] Preferably, the steel cord detection rapid correction method is manually started when the steel cord detection device is in a stop state; or is manually or automatically started when the steel cord detection device is in a normal scanning state.

[0036] Preferably, when the steel cord detection device is in a normal scanning state, the timing of starting the steel cord detection rapid correction method each time is determined based on whether the result of the normal scanning data after being corrected by the last steel cord detection rapid correction method meets the uniformity requirement.

[0037] Another aspect of the present application provides a steel cord detection device for detecting defects of a steel cord, comprising a detection unit, an encoder, a processor and a storage unit, the detection unit comprising a magnetic field module, a magnetic sensor module and a steel cord detection channel formed by the magnetic field module and the magnetic sensor module.

[0038] The steel cord detection device is corrected by the above steel cord detection rapid correction method.

[0039] The technical solution provided by the embodiments of the present application sets the detection and correction steps to be performed in a normal scanning state, so that the correction of the steel cord detection device can effectively eliminate the magnetic sensor error caused by the mutual coupling between the steel cord and the excitation magnetic field and the resulting strip-shaped undulation of the steel cord magnetic image, thereby ensuring that the generated magnetic image can truly reflect the distribution of the steel cord inside the steel cord.

[0040] In addition, the rapid correction method of the present application performs effectiveness detection using the plurality of rows of original scanning data before generating the correction data, thereby avoiding the problem that the correction data itself has errors due to the existence of joints in the scanning position, steel cord defects and the like. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 FIG. 1 is a structural diagram of a magnetic sensor module in an existing steel cord detection device;

[0042] Figure 2 FIG. 2 is a schematic diagram of the working principle of the magnetic sensor module shown in FIG. 1; Figure 1

[0043] Figure 3 FIG. 3 is a schematic diagram of the magnetic image generated by the scanning data obtained by the steel cord detection device shown in FIG. 1 detecting the steel cord; Figure 1

[0044] Figure 4 ​​A flow chart of the method for rapid correction of the steel cord detection according to the embodiment of the present application;

[0045] Figure 5 A side view of a specific steel cord;

[0046] Figure 6a A specific magnetic field strength amplitude condition obtained by scanning a magnetic sensitive element and its average condition in an integer number of periods;

[0047] Figure 6b A specific magnetic field strength amplitude condition obtained by scanning a magnetic sensitive element and its average condition in a non-integer number of periods;

[0048] Figure 7 A schematic diagram of a magnetic image generated by the scanning data obtained by the corrected steel cord detection device detecting the steel cord;

[0049] Figure 8 A schematic diagram of the layout of the steel cord detection device according to the embodiment of the present application;

[0050] Figure 9 A side view of the steel cord detection device according to the embodiment of the present application;

[0051] Figure 10 A system framework diagram of the steel cord detection device according to the embodiment of the present application;

[0052] Figure 11 A data conversion schematic diagram when the steel cord detection device according to the preferred embodiment of the present application is corrected;

[0053] Figure 12 A data conversion schematic diagram when the steel cord detection device according to the preferred embodiment of the present application is corrected. DETAILED DESCRIPTION

[0054] Hereinafter, the present application will be further described based on the preferred embodiments and with reference to the accompanying drawings.

[0055] The words in the specification are used for explaining the embodiments of the present application, but are not intended to limit the present application. It should also be noted that, unless explicitly specified and limited, if the terms "arranged", "connected", "linked" appear, they should be understood broadly, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, can be directly connected, or indirectly connected through an intermediate medium, can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be specifically understood. In addition, in order to facilitate understanding, the various components on the drawing are enlarged or reduced, but this practice is not intended to limit the protection scope of the present application.

[0056] Figure 1 The structural diagram of a core component of an existing steel cord detection device, a magnetic sensor module, is shown, Figure 2 For its working principle, the specific structure and layout of the steel cord detection device can refer to the patent (such as the invention patent with application number CN202111032892.X) already applied by the inventor.

[0057] As shown in Figure 1 , Figure 2 , the magnetic sensor module 221 includes a shell 50, an array of multiple spaced magnetic sensitive elements 2210 arranged inside the shell (generally, the arrangement direction of the array is called the scanning direction), an excitation unit composed of a magnet 2121, and a serial output chip 2211, etc. Each magnetic sensitive element 2210 is placed in the excitation magnetic field generated by the excitation unit. When the detection object 40 moves in the excitation magnetic field (generally, the movement direction of the detection object is called the sub-scanning direction), the magnetic sensitive part 40' contained therein cuts the magnetic force lines of the excitation magnetic field, so that the magnetic sensitive element 2210 senses the change of the magnetic field, and transmits it to the serial output chip 2211 in the form of an electrical signal V o through the data line 70. The serial output chip 2211 outputs the V o output by the multiple magnetic sensitive elements 2210 in the form of a serial signal Vsig. In the process of continuously detecting, the magnetic sensor module 221 continuously performs the above-mentioned acquisition of Vsig signal according to the sampling interval, and each acquisition of Vsig is also called one row of scanning, Figure 3 The schematic diagram of the magnetic image of the steel cord obtained by scanning the steel cord using the magnetic sensor module is shown. In this image, each pixel in the vertical direction represents the magnetic field strength value obtained by each magnetic sensitive element during one row of scanning. By splicing multiple rows of scanning data, the magnetic image of the steel cord can be obtained. Through the magnetic image, Figure 3 , it can be seen that the steel cord in the steel cord is periodically distributed, and the steel cord in the steel cord is detected, such as the steel cord, the missing line, the intersection, the fracture, etc.

[0058] However, as shown in the upper and lower dashed box diagrams in Figure 3 , due to the difference in performance parameters between different magnetic sensitive elements, the scanning results of the same magnetic field intensity may be different, resulting in different light and dark areas in the magnetic image. Since the above light and dark difference is caused by the non-uniformity of the magnetic sensitive element itself, not by the performance difference of the steel cord, it is necessary to correct the magnetic sensitive element in the magnetic sensor module to eliminate the misjudgment of the steel cord defects caused by the above difference.

[0059] The common way to correct the steel cord detection device is to correct the steel cord detection device before it scans the steel cord normally, or to design some moving structure to move away from the detection part to reduce the influence on the magnetic sensitive element. However, the above-mentioned correction method for the magnetic sensitive element in the non-working state often fails to achieve the desired effect, because the magnetic image of the steel cord scanned by the magnetic sensor module in the working state is based on the change of the magnetic field caused by the cutting of the steel cord contained in the steel cord under the motion state. At the same time, the moving steel cord is magnetized by the excitation magnetic field, which in turn causes further change of the magnetic field. The mutual coupling between the steel cord in the steel cord and the excitation magnetic field of the magnetic sensor module is constantly accumulating and changing during the normal scanning process. The non-uniformity of each magnetic sensitive element caused by this is obviously impossible to eliminate by correcting the non-scanning state of the magnetic sensitive element, but needs to be corrected in the continuous normal scanning process. After each correction, it is still necessary to determine whether to restart the correction according to whether the new non-uniformity appears in the scanning data after correction due to the mutual action of the steel cord and the excitation magnetic field.

[0060] To realize more accurate correction of the steel cord detection device, the application provides a new steel cord detection fast correction method, Figure 4 The flow chart of the method is shown in some embodiments, as shown in the figure, the method comprises the following steps: Figure 4

[0061] S100: determining the effective detection row number L based on the period number T, the steel cord detection device parameter information and the steel cord parameter information;

[0062] S200: scanning the steel cord moving along the sub-scanning direction by the steel cord detection device;

[0063] S300: performing effectiveness detection on the original scanning data obtained by scanning, determining at least one group of effective data passing the effectiveness detection from the original scanning data, and generating correction data based on the effective data, the effective data containing L rows of original scanning data;

[0064] S400: correcting the steel cord detection device using the correction data.

[0065] ​The process involves first determining the number of validity detection rows L in step S100 (as explained earlier, one scan using the magnetic sensor module is equivalent to scanning one row), then scanning the steel wire curtain in motion in step S200, and further validating the raw scan data in step S300. Then, using the L rows of raw scan data that have passed the validity detection, correction data is generated. Finally, in step S400, the correction data is used to calibrate the steel wire curtain detection device.

[0066] The reason for performing validity checks on the multiple lines of raw scanning data acquired by the steel cord fabric inspection device is that, due to the presence of seams in the steel cord fabric, or defects such as strand bundling, missing strands, and crossings in certain locations, the distribution of steel cords at these locations is uneven. The corresponding raw scanning data itself is defective data. Therefore, it is necessary to remove the raw data acquired at these locations through validity checks to ensure the uniformity of the data used for subsequent correction.

[0067] The steps S100 to S400 described above will be explained in detail below with reference to the accompanying drawings and specific embodiments.

[0068] Step S100 is used to determine the number L of scan data for validity testing. In some preferred embodiments, L is determined based on the following formula:

[0069] L = T * G * R / 25.4,

[0070] Where T is the number of cycles, G is the spacing of the steel wire cords in the steel wire curtain along the sub-scanning direction in mm, and R is the resolution of the magnetic sensor module included in the steel wire curtain detection device in DPI. In some specific embodiments, the resolution can be calculated by parameters such as the number of pulses per encoder revolution P, the encoder wheel diameter D, and the frequency division coefficient α.

[0071] The following combination Figure 5 Explain the meaning of L.

[0072] Figure 5 A side sectional view of a specific steel wire curtain 4 is shown, as follows: Figure 5As shown, the steel cord 4 is made of a plurality of steel cords 41 evenly spaced and coated with rubber or the like. The distance between two adjacent steel cords 41 along the sub-scan direction (i.e. the movement direction of the steel cord) is G, in mm. T is the number of periods, and T*G is the length of T periods of steel cords. Further, R is the resolution of the magnetic sensor module in DPI, and dividing it by 25.4 gives the number of scans (the number of scanning lines) of the magnetic sensor module when the steel cord moves 1 mm. Finally, L is the number of scanning lines of the magnetic sensor module when the steel cord moves T periods of steel cords along the sub-scan direction.

[0073] In some preferred embodiments, T is an integer greater than or equal to 2, Figure 5 The scanning areas of the steel cord corresponding to L scanning lines when T = 2, 3 and n are shown respectively.

[0074] The following Figure 6a , Figure 6b explains the specific reasons for T taking an integer greater than or equal to 2 in the preferred embodiments of the application.

[0075] Figure 6a The upper half shows the amplitude of the magnetic field intensity output by a certain pixel point (i.e. a magnetic sensitive element) in the movement direction of the steel cord in 3 periods of steel cords. The magnetic sensitive element periodically appears directly above the steel cord, and the amplitude of its output signal also periodically appears maximum and minimum, further forming the peaks and troughs of the signal. However, in general, the sum of the amplitudes of each row of the output of the magnetic sensitive element in each period of the steel cord is the same, i.e. the area of the shadow in the figure in one period is the same. Then the average value in each period is also the same after averaging.

[0076] Figure 6a The lower half shows that the average output of the same magnetic sensitive element in 3 periods is the same. Similarly, the average output in 4 periods or 2 periods or the like and other integer periods should also be the same.

[0077] For comparison, Figure 6bThe average of the amplitude of the magnetic field intensity obtained by scanning the magnetic sensitive element in two half periods of the movement direction of the steel cord is calculated. As can be seen from the figure, the different starting positions of the calculation will lead to different averages when the average is calculated by taking non-integer periods. Obviously, only by taking the average of integer periods, the influence of the periodic change of the magnetic field intensity on the average calculation can be offset, and the output data average of each pixel point in the ideal standard working environment can be obtained. Using this data for correction calculation, the influence of the steel wire in the steel cord can be ignored. The steel cord is not adjusted in position at this time, and the environment of the steel cord detection device is exactly the same as the scanning state, which can be called a standard and ideal correction environment.

[0078] Further, by counting the phenomena of missing lines, parallel lines and intersections of steel cords in the steel cord, it is found that when the above-mentioned steel cord arrangement has problems, the affected area at least spans 1.5 arrangement periods. Therefore, in order to avoid that the correction data calculation area falls into the area where the above-mentioned steel cord arrangement has defects, it is necessary to detect the effectiveness of data of at least 2 integer periods, therefore, in some preferred embodiments, the number of periods T is an integer greater than or equal to 2.

[0079] In step S200, the steel cord detection device scans the steel cord moving along the sub-scanning direction and obtains multiple rows of original scan data. Specifically, each row of original scan data contains N magnetic field intensity values V0(j), j=1, 2…N obtained along the scanning direction, where N is the number of magnetic sensitive elements contained by the magnetic sensor module along the scanning direction.

[0080] Step S300 is used to detect the effectiveness of the multiple rows of original scan data obtained in step S200, and generate correction data using the L rows of original scan data detected by the effectiveness detection. Specifically, in some embodiments, the effectiveness detection in step S300 includes the following steps:

[0081] S310: extract a group of L rows of original scan data V0(i,j), i=1, 2…, L, j=1, 2…, N;

[0082] S320: calculate the average of the original scan data Ave V k :

[0083]

[0084] S330: compare Ave V k two by two, and calculate the difference between any two Ave V k ;

[0085] S340: determine whether there are any two Ave Vk If the difference exceeds a preset threshold value, step S350 is executed, otherwise step S360 is executed;

[0086] S350: store the L rows of original scanning data as invalid data V n (i,j), i=1,2…L, j=1,2…N, and return to step S310;

[0087] S360: store the L rows of original scanning data as valid data V e (i,j), i=1,2…L, j=1,2…N, and end the validity detection.

[0088] Specifically, the above steps S310 to S330 are described by taking T=3 as an example.

[0089] When T=3, the L rows of original scanning data collectively contain the results of scanning the range of 3 steel cord cycles. Each cycle contains L / 3 rows of original scanning data, and each row of original scanning data contains N magnetic field strength values obtained by the magnetic sensitive unit, wherein,

[0090] The original scanning data of the first cycle is denoted as V0(i,j), i=1,2,…,L / 3, j=1,2,…,N,

[0091] The original scanning data of the second cycle is denoted as V0(i,j), i=L / 3+1,L / 3+2,…,2*L / 3, j=1,2…N,

[0092] The original scanning data of the third cycle is denoted as V0(i,j), i=2*L / 3+1,2*L / 3+2,…,L, j=1,2…N.

[0093] The average values of the original scanning data of the above three cycles are calculated respectively, wherein,

[0094] The average value Ave V1 of the original scanning data of the first cycle is:

[0095]

[0096] The average value Ave V2 of the original scanning data of the second cycle is:

[0097]

[0098] The average value Ave V3 of the original scanning data of the third cycle is:

[0099]

[0100] Ave V1-Ave V2, Ave V2-Ave V3 and Ave V3-Ave V1 are calculated respectively. If any of the above three differences exceeds a preset threshold value, it means that the steel cord corresponding to the L rows of original scanning data may be at the joint, or there are defects in the three corresponding steel cords, resulting in a large difference in the mean value of the three periods. At this time, the L rows of original scanning data of this group are stored as invalid data V n (i,j), i=1, 2…L, j=1, 2…N, and then re-extracting L rows of original scanning data and repeating the above mean value calculation and comparison operation, otherwise the L rows of original scanning data of this group are stored as valid data V e (i,j), i=1, 2…L, j=1, 2…N and end the validity detection. The valid data of this group can be used for subsequent correction operation.

[0101] Further, the correction data is determined based on the following formula:

[0102]

[0103] Wherein, V is a preset correction reference value.

[0104] In the above formula, first, the L values V e obtained by scanning each magnetic sensitive element in the N magnetic sensitive elements are averaged, and then the difference between the above average value of each magnetic sensitive element and the preset correction reference value is calculated. The above difference represents the overall deviation of the output of each magnetic sensitive element after averaging the output of the magnetic sensitive element over an integer number of steel cord spacing periods relative to the correction reference value.

[0105] After obtaining the correction data through step S300, the above correction data can be used to calibrate the steel cord detection device in step S400. In some specific embodiments, step S400 further includes the following steps:

[0106] S410: scanning the steel cord moving along the sub-scanning direction by the steel cord detection device and obtaining multiple rows of normal scanning data, wherein each row of normal scanning data contains N magnetic field strength values V(j), j=1, 2,…,N obtained along the scanning direction;

[0107] S420: determining each row of corrected scanning data by the following formula:

[0108] EV(j)=V(j)+K(j), j=1, 2,…,N.

[0109] Figure 7 A schematic diagram of the magnetic image generated by the corrected scanning data obtained by the corrected steel cord detection device for detecting the steel cord is shown. By comparing Figure 7 withFigure 3 It can be seen that, after the steel cord detection device is corrected by the above correction method, the fluctuation phenomenon of the strip-shaped intensity caused by the unevenness of the different magnetic sensitive element performances is obviously eliminated, so that the corrected scanning data can truly reflect the magnetic field intensity change caused by the steel cord cutting excitation magnetic field, and the misjudgment of the steel cord defects caused by the performance difference of the different magnetic sensitive elements is avoided.

[0110] Further, in some preferred embodiments of the present application, step S400 further comprises correcting the multiple rows of original scanning data obtained in step S200 using the above correction data.

[0111] Specifically, as described above, the multiple rows of original scanning data obtained in step S200 are detected for validity and can be respectively stored as invalid data and valid data. The invalid data and the valid data are the results of the steel cord detection device detecting the steel cord, and there is an overall strip-shaped offset caused by the unevenness of the magnetic sensitive elements. Therefore, by correcting the multiple rows of original scanning data using the correction data, the corrected original scanning data is also used to generate the magnetic image of the steel cord, thereby ensuring the continuity of the steel cord defect detection.

[0112] Specifically, the invalid data is corrected as follows:

[0113] EV n (i,j)=V n (i,j)+K(i,j),i=1,2,…,L,j=1,2,…,N.

[0114] Specifically, the valid data is corrected as follows:

[0115] EV e (i,j)=V e (i,j)+K(i,j),i=1,2,…,L,j=1,2,…,N.

[0116] It should be noted that the steel cord detection rapid correction method can be manually started when the steel cord detection device is in a stopped state, like a conventional correction method, or can be manually or automatically started when the steel cord detection device is in a normal scanning state. In particular, when the steel cord detection device is in a normal scanning state, the method is started, since each magnetic sensitive element is in a real working state and in an excitation magnetic field environment, the deviation obtained relative to the preset correction reference value at this time is the real-time deviation under the real working state and environment, thereby effectively avoiding the problem of inaccurate correction results caused by correction in other correction environments.

[0117] It should be noted that after the steel cord detection device is corrected by using the method each time, the corrected normal scanning data still needs to be detected, because the cutting of the steel cord on the excitation magnetic field is a continuous process, and with the continuous process of the above process, the characteristics of each magnetic sensitive element change differently, and then after a period of time, the corrected data cannot truly reflect the deviation of the scanning value and the correction reference value of each magnetic sensitive element, resulting in the reappearance of the strip deviation of the corrected normal scanning data, at which time the correction needs to be performed again.

[0118] In some preferred embodiments, when the steel cord detection device is in a normal scanning state, the timing of starting the steel cord detection fast correction method each time is determined based on whether the result of the normal scanning data after the last steel cord detection fast correction method correction meets the uniformity requirement.

[0119] Specifically, each row of corrected normal scanning data EV(j), j = 1, 2, …, N, each value EV(1), EV(2), …, EV(N) should be equal or close to equal, so that the mean operation can be performed on multiple rows of scanning data as follows:

[0120]

[0121] Then, by comparing Ave EV(j) two by two to judge its uniformity, if there is at least one group of comparison results exceeding the preset threshold, it is judged that the current correction data has failed, and the method needs to be used to correct the steel cord detection device again.

[0122] The application also provides a steel cord detection device, which is corrected by the above-mentioned steel cord detection fast correction method. As described above, the correction can be started when the steel cord detection device is in a shutdown state, or can be started when the steel cord detection device is in a normal scanning state.

[0123] Figure 8 A layout diagram of the steel cord detection device in some preferred embodiments is shown, Figure 9 is a side view of the steel cord detection device, Figure 10 is a system framework diagram of the steel cord detection device.

[0124] As Figure 8 to Figure 10As shown, the steel cord detection device comprises a detection unit, an encoder 3, a processor 5 and a storage unit 6, wherein the detection unit comprises a magnetic field module 1 and a magnetic sensor module 2, the magnetic field module 1 and the magnetic sensor module 2 are oppositely arranged along the Z-axis direction at both sides of the width of the steel cord 4, thereby forming a steel cord detection channel 800. When the steel cord detection device detects and / or corrects the steel cord 4, the steel cord 4 is driven to move along the Y-axis direction (the sub-scanning direction) by the driving device such as a roller, and passes through the above-mentioned steel cord detection channel 800, the steel cord contained therein cuts the excitation magnetic field generated by the magnetic field module, and the changing magnetic field strength value is scanned and obtained by the magnetic sensor module. The encoder 3 is in good contact with the steel cord 4 through the encoder roller, and obtains the movement speed information of the steel cord 4.

[0125] Further, the magnetic field module 1 comprises a magnetic field module shell 12 and a permanent magnet 11 extending along the X-axis direction (the scanning direction), wherein the permanent magnet is fixedly arranged in the magnetic field module shell and close to the side of the magnetic field module shell 12 facing the magnetic sensor module 2; the magnetic sensor module comprises a chip substrate 21, a magnetic sensitive element array 211 and a magnetic sensor module shell 22, wherein the chip substrate 21 is fixedly arranged inside the magnetic sensor module shell 22 and close to the side of the magnetic sensor module shell 22 facing the magnetic field module 1, the magnetic sensitive element array 211 is arranged on the surface of the side of the magnetic sensor module shell 22 facing the magnetic field module 1, and comprises a plurality of magnetic sensitive elements arranged at intervals along the X-axis direction.

[0126] Preferably, the processor 5 and the storage unit 6 are fixedly arranged inside the magnetic sensor module shell 22, the processor is used to control the steel cord detection device to detect the steel cord, and the storage unit is used to store the data required in the detection and correction process and the generated data.

[0127] Figure 11 As shown, in a preferred embodiment, a data conversion schematic diagram when the steel cord detection device corrects is shown, as shown in Figure 11 As shown, in this embodiment, the processor 5 further comprises a scanning synchronization unit 501, an acquisition unit 502, a calculation processing unit 503, an image correction unit 504, a control, execution and processing unit 505 and an interface unit 506.

[0128] The scanning synchronization unit 501 provides line scanning synchronization signals for each subsequent scanning step based on the speed information of the steel cord 4 provided by the encoder. The acquisition unit 502 is connected to the detection unit and is used to acquire the multi-line raw scanning data in step S200 and the normal scanning data in step S400. In this embodiment, the acquisition unit 502 includes an A / D conversion module, which can convert analog voltage signals into digital signals. The calculation processing unit 503 is used to perform the validity detection and generate correction data in step S300. The storage unit 6 is used to store the multi-line raw scanning data, valid data, invalid data, correction data, and the steel cord detection device parameter information and the steel cord parameter information in step S100. The data correction unit 504 is used to perform the correction operation in step S400. The control, execution and processing unit 505 is used to provide clock signals, control operation instructions, accept data and instructions from the interface unit 506, control each unit to perform the steps of the above-mentioned correction method, and generate a magnetic map of the steel cord 4 based on the corrected normal scanning data. In addition, the control, execution and processing unit 505 also includes a determination module for calculating and determining the determination conditions for automatically starting the correction. The interface unit 506 is used to transmit the above-mentioned data and communicate with other external devices. The specific working process of the steel cord detection device for correction has been described in detail above, and will not be repeated here.

[0129] Figure 12 A data conversion schematic diagram of the steel cord detection device for correction in another preferred embodiment is shown.

[0130] The difference between this embodiment and the embodiment shown in Figure 11 In this embodiment, the data correction unit 504 has a DA conversion function. Specifically, after the steel cord detection device generates and stores the correction data, in the normal scanning state, Figure 11 In the embodiment shown in In this embodiment, the above-mentioned correction is performed in the analog electric signal field, that is, when the analog electric signals of each row of magnetic field strength acquired by the magnetic sensor module 2 are output in series, the control, execution and processing unit 505 controls the storage unit 503 to provide the corresponding correction data in sequence, which is converted into analog electric signals by the data correction unit 504 and fed back to the operational amplifier unit of the magnetic sensor module 2 for output deviation compensation.

[0131] The steel cord magnetic field image signal generated in the embodiment is compensated for deviation of each pixel point before being sampled and quantized by the acquisition unit 501, so that the analog signal output by the detection unit is a signal with uniform amplitude after compensation, i.e., the output signals of the corresponding magnetic sensitive units are substantially the same. Since the initial output analog signals of the magnetic sensitive elements are substantially the same, this method can also greatly increase the sensing range of the steel cord detection device, making it possible to detect more types of steel cord.

[0132] The specific embodiments of the application are described above in detail, and those skilled in the art can make some improvements and modifications to the application without departing from the principles of the application. These improvements and modifications also belong to the protection scope of the claims of the application.

Claims

1. A method for rapid correction of a steel cord detection device, for rapid correction of a steel cord detection device, characterized in that, The method comprises the following steps: S100: determining the effective detection row number L based on the cycle number T, the steel cord detection device parameter information, and the steel cord parameter information; S200: scanning the steel cord moving along the sub-scanning direction by the steel cord detection device; S300: performing effectiveness detection on the original scanning data obtained by scanning, determining at least one group of effective data passing the effectiveness detection from the original scanning data, and generating correction data based on the effective data, wherein the effective data contains L rows of original scanning data; S400: correcting the steel cord detection device using the correction data; The cycle number T is an integer greater than or equal to 2; The effectiveness detection in step S300 further comprises the following steps: S310: Extract a set of L rows of original scan data , ; Wherein N is the number of magnetic sensitive elements contained in the magnetic sensor module of the steel cord detection device along the scanning direction; S320: Calculate the mean of the raw scan data for each cycle based on the following formula : Wherein G is the pitch of the steel cord contained in the steel cord along the sub-scanning direction, with the unit of mm, and R is the resolution of the magnetic sensor module contained in the steel cord detection device, with the unit of DPI; S330: performing pairwise comparison on the difference between any two of the ​ S340: judging whether the difference between any two of the distances exceeds a preset threshold value, and if the result of the judgment is yes, executing step S350, otherwise executing step S360. S340: judging whether the difference between any two of the distances exceeds a preset threshold value, and if the result of the judgment is yes, executing step S350, otherwise executing step S360. S350: store the set of L rows of raw scan data as invalid data , and return to step S310; S360: store the set of L rows of raw scan data as valid data by validity detection , and end the validity detection; The correction data is determined based on the following formula: Wherein V is a preset correction reference value.

2. The steel cord detection rapid correction method according to claim 1, wherein: The original scanning data is the magnetic field intensity value scanned and obtained by the steel cord detection device when the steel cord moves.

3. The steel cord inspection quick correction method according to claim 1, characterized in that, L is determined based on the following formula: L = T G R / 25.4, Wherein G is the pitch of the steel cord contained in the steel cord along the sub-scanning direction, with the unit of mm, and R is the resolution of the magnetic sensor module contained in the steel cord detection device, with the unit of DPI.

4. The steel cord detection rapid correction method according to claim 3, wherein: Each row of raw scan data contains N magnetic field strength values taken along the scan direction where N is the number of magnetically sensitive elements contained in the magnetic sensor module along the scan direction; The scanning direction is perpendicular to the sub-scanning direction and parallel to the width of the steel cord.

5. The steel cord inspection quick correction method according to claim 1, characterized in that, Step S400 further comprises the following steps: S410: scanning the steel cord moving along the sub-scanning direction by the steel cord detection device and obtaining a plurality of rows of normal scanning data, wherein each row of normal scanning data contains N magnetic field strength values acquired along the scanning direction ; S420: determining each row of corrected scanning data by the following formula: 。 6. The steel cord detection rapid correction method according to claim 1, wherein: Step S400 further comprises correcting the original scanning data using the correction data.

7. The steel cord detection rapid correction method according to claim 1, wherein: The steel cord detection rapid correction method is manually started when the steel cord detection device is in a shutdown state; or, The steel cord detection rapid correction method is manually or automatically started when the steel cord detection device is in a normal scanning state.

8. The steel cord detection rapid correction method according to claim 7, wherein: When the steel cord detection device is in a normal scanning state, the timing of starting the steel cord detection rapid correction method each time is determined based on whether the result of the normal scanning data after being corrected by the steel cord detection rapid correction method last time meets the uniformity requirement.

9. A steel cord detection device for detecting defects of a steel cord, comprising a detection unit, an encoder, a processor, and a storage unit, the detection unit comprising a magnetic field module, a magnetic sensor module, and a steel cord detection channel formed by the magnetic field module and the magnetic sensor module, characterized in that: The steel cord detection device is corrected by the steel cord detection rapid correction method as claimed in any one of claims 1 to 8.

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