A metal wire state detection method

Abstract

The application provides a metal wire state detection method for detecting an abnormal state of a metal wire in a running state, comprising the following steps: when the metal wire is in the running state, a first eddy current sensor is controlled to move along an axial direction of a corresponding processing roller at a set speed; a detection signal collected by the first eddy current sensor is acquired, and it is determined whether the metal wire wound on the processing roller is in an abnormal state based on the acquired detection signal. The application can detect the abnormal state of the metal wire in the running state.

Description

Technical Field

[0001] This invention relates to the field of detection, and in particular to a method for detecting the state of metal wires. Background Technology

[0002] In some applications, such as silicon wafer dicing, slicing machines are used to cut silicon wafers. The slicing machine's automatic wire routing system first releases a diamond wire, approximately 200-300 km long and with a finished diameter of 50-65 μm (even approaching 30 μm), from the feed roller into the dicing area. This wire is then evenly and precisely wound repeatedly onto the main roller within the dicing area. The main roller has fine winding grooves, within which individual diamond wires are arranged side-by-side to form a mesh of approximately 3,000 wires with a spacing of less than 250 μm. The wire is then taken out from the dicing area by the take-up roller. Since both the diamond wire diameter and mesh density are at the micrometer level, precise wire routing places high demands on the diamond wire management system. Its characteristics include fine wire (reducing silicon rod loss), high density (increasing the number of wafers produced per unit silicon rod length), and equal spacing (avoiding inconsistent silicon wafer thickness), which facilitates improved wafer output efficiency.

[0003] During silicon wafer dicing, the upper surface of the silicon rod is fixed in the dicing equipment. The silicon rod moves slowly downwards, and the linear velocity of the diamond wire mesh accelerates from a standstill to over 2,400 meters per minute (equivalent to 144 kilometers per hour) within 4 seconds. After maintaining this high speed for about 30 seconds, it decelerates to 0 meters per minute within 4 seconds; then the motion repeats in the opposite direction. The diamond wire mesh cuts the silicon rod through this reciprocating high-speed motion. Wire bowing refers to the degree of bending of the wire saw during cutting, which affects cutting efficiency. If the tensile strength or yield strength of the diamond wire is insufficient, the cutting force is insufficient, or the cutting parameters are not coordinated with the diamond wire parameters, wire breakage will occur, which will significantly damage production continuity and increase non-silicon costs. Therefore, the breakage rate of the diamond wire should be kept as low as possible, and wire breakage should be detected promptly. Summary of the Invention

[0004] To address the aforementioned technical problems, the technical solution adopted by this invention is as follows:

[0005] This invention provides a method for detecting the state of a metal wire, used to detect abnormal states of a metal wire in transit. The application scenario of the method includes at least: a first wiring roller, a second wiring roller, a first wiring roller drive unit, a second wiring roller drive unit, at least two parallel processing rollers, a processing roller drive unit, and a first eddy current sensor. The first eddy current sensor is disposed on the side of any one of the at least two processing rollers. The metal wire is wound around the at least two processing rollers, with one end connected to the first wiring roller and the other end connected to the second wiring roller. The first wiring roller and the second wiring roller rotate under the drive of the first wiring roller drive unit and the second wiring roller drive unit, respectively, so that the metal wire travels between the first wiring roller and the second wiring roller and wound around the at least two processing rollers driven by the processing roller drive unit. The method includes the following steps:

[0006] S100, when the metal wire is in a traveling state, control the first eddy current sensor to move along the axial direction of the corresponding processing roller at a set speed.

[0007] S200: Acquire the detection signal DS1 collected by the first eddy current sensor, and determine whether the metal wire wound on the processing roller is in an abnormal state based on DS1 and DS10; wherein, if (DS1-DS10)>d0, it is determined that the metal wire wound on the processing roller is in a parallel state, and if (DS10-DS1)>d0, it is determined that the metal wire wound on the processing roller is in a broken state, and the corresponding prompt signal is output; DS10 is the detection signal threshold corresponding to DS1, and d0 is the set error threshold.

[0008] The present invention has at least the following beneficial effects:

[0009] The metal wire state detection method provided in this embodiment of the invention can detect abnormal states of metal wires in real time, thereby improving the processing quality of the workpiece. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a schematic diagram illustrating an application scenario according to an embodiment of the present invention;

[0012] Figure 2 This is a structural schematic diagram of an application scenario according to another embodiment of the present invention;Figures 3 to 7 This is a schematic diagram of metal wire abnormality detection provided by the present invention;

[0013] Figure 8 This is a schematic flowchart of a metal wire state detection method provided in an embodiment of the present invention. Detailed Implementation

[0014] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] This invention provides a method for detecting the state of a metal wire, used to detect abnormal states of a metal wire in motion; such as... Figure 1 As shown, the application scenarios of the method include at least: a first wiring roller 1, a second wiring roller 2, a first wiring roller drive unit (not shown), a second wiring roller drive unit (not shown), at least two parallel processing rollers, a processing roller drive unit (not shown), and a first eddy current sensor 5.

[0016] In this embodiment of the invention, the processing roller drive unit is used to drive the at least two processing rollers, causing the at least two processing rollers to rotate around the same rotation direction. The processing roller drive unit may be a servo motor. The two processing rollers are arranged in parallel, and each processing roller has a plurality of grooves formed at a set interval on its outer circumferential surface. The depth and width of the grooves can be set according to actual needs. The number of grooves and the spacing between the grooves can also be set according to actual needs. In a non-limiting embodiment, the number of grooves may be 3000, and the spacing between the grooves may be less than 250 μm.

[0017] In embodiments of the present invention, such as Figure 1 As shown, the metal wire 6 is wound around the at least two processing rollers. One end of the metal wire is connected to the first wire distribution roller 1, and the other end is connected to the second wire distribution roller 2. The first wire distribution roller 1 and the second wire distribution roller 2 rotate under the drive of the first wire distribution roller drive unit and the second wire distribution roller drive unit, respectively, so that the metal wire travels between the first wire distribution roller and the second wire distribution roller and is wound around the at least two processing rollers driven by the processing roller drive unit. In an illustrative example, as... Figure 1 As shown, it may include two processing rollers, namely a first processing roller 3 and a second processing roller 4. In another illustrative embodiment, as... Figure 2 As shown, it may include three processing rollers, namely a first processing roller 3, a second processing roller 4, and a third processing roller 9. The three processing rollers may be arranged in an isosceles triangle. Further, as... Figure 1As shown, the first wire feeding roller 1 and the processing roller are connected by multiple guide wheels 7 for wire feeding, and the second wire feeding roller 2 and the processing roller are also connected by multiple guide wheels for wire feeding. In this embodiment of the invention, each guide wheel can be driven by a corresponding drive mechanism (not shown).

[0018] Specifically, when the number of metal wires wound on the first wiring roller exceeds a first preset threshold, the first wiring roller releases the metal wires, and the second wiring roller receives the metal wires. Conversely, when the number of metal wires wound on the first wiring roller is less than a second preset threshold, the first wiring roller receives the metal wires, and the second wiring roller releases the metal wires. In other words, the first wiring roller and the second wiring roller can function as both wire-feeding rollers and wire-receiving rollers. The first and second preset thresholds can be set based on actual needs. Each wiring roller can be driven by a corresponding drive unit, such as a servo motor.

[0019] In another embodiment of the present invention, the application scenario further includes a workpiece 8. The workpiece 8 is disposed above or below the processing roller. The metal wire wound on the processing roller is used to cut the workpiece when the processing roller is in a driving state. Specifically, in this embodiment of the present invention, when a single metal wire conveyed by the wiring roller is transmitted to the processing roller, since both ends of the metal wire are fixed by the wiring roller, it will be tightly wound in the wire groove of the processing roller under the action of the processing roller driving part, forming a tightly arranged metal wire mesh. During the cutting process of the workpiece, the upper surface of the workpiece is fixed in the cutting equipment, and the workpiece moves downward slowly. The linear speed of the metal wire mesh accelerates from a stationary state to a set speed of, for example, 2400 meters / minute (equivalent to 144 kilometers / hour) or more within a set time, for example, 4 seconds. After a set high-speed continuous operation for, for example, about 30 seconds, it decelerates to 0 meters / minute within 4 seconds; then the reverse movement is repeated; the metal wire mesh achieves the cutting of the workpiece through this reciprocating high-speed movement. In this embodiment of the present invention, the metal wire can be diamond wire, and the workpiece can be a silicon wafer. As those skilled in the art know, the core component of an eddy current sensor probe is a detection coil. When a high-frequency AC signal is applied to the detection coil, the high-frequency magnetic field generated by the coil induces eddy currents within the metal conductor. These eddy currents, in turn, affect the magnetic field strength and ultimately alter the inductance and resistance of the detection coil. The demodulation circuit, by acquiring the coil's impedance information and based on the relationship between impedance and distance, can demodulate the change in displacement. In this invention, utilizing the characteristics of diamond wire as a metal and the eddy current sensor, the abnormal state of the diamond wire is detected by utilizing the signal changes detected by the eddy current sensor.

[0020] In this embodiment of the invention, the eddy current sensor can be of an existing structure. For example, it can be divided into an integrated circuit type or a probe + controller type. The integrated circuit type has the circuitry integrated inside the probe, eliminating the need for an additional controller, thus facilitating installation and saving space. The probe + controller type features a low coefficient of thermal expansion and a large measurement range.

[0021] Furthermore, in this embodiment of the invention, the first eddy current sensor is disposed on the side of any one of the at least two processing rollers, and is used to move along the axial direction of the processing roller to detect the coiling and breaking states of the wound metal wire. Taking three processing rollers as an example, the first eddy current sensor 5 can be disposed on the side of the first processing roller 3 or the second processing roller 4, such as... Figure 3 As shown, the first eddy current sensor 5 can be positioned at a predetermined location on the left side of the first processing roller 3. The distance between the first eddy current sensor 5 and the processing roller can be determined based on actual conditions; theoretically, the closer the better, as this ensures more accurate detection signals. In one illustrative embodiment, the distance between the first eddy current sensor 5 and the metal wire can be 2 mm. The first eddy current sensor 5 can be driven by a corresponding drive unit (not shown) to move along the axial direction of the processing roller at a set speed. In this embodiment of the invention, the number of metal wires detected per unit ΔL1 by the first eddy current sensor 5, i.e., the number of metal wires that can be detected each time, can be determined based on actual conditions, as long as detection accuracy can be ensured. In one illustrative embodiment, ΔL1 can be 10 to 20 wires.

[0022] Furthermore, the methods provided in the embodiments of the present invention may include, for example: Figure 8 The steps shown are as follows:

[0023] S100, when the metal wire is in the traveling state, control the first eddy current sensor to move along the axial direction of the corresponding processing roller at a set speed.

[0024] S200: Obtain the detection signal DS1 collected by the first eddy current sensor, and determine whether the metal wire wound on the processing roller is in an abnormal state based on DS1 and DS10.

[0025] If (DS1-DS10)>d0, it is determined that the metal wire wound on the processing roller is in a parallel state; if (DS10-DS1)>d0, it is determined that the metal wire wound on the processing roller is in a broken state, and a corresponding prompt signal is output; DS10 is the detection signal threshold corresponding to DS1, and d0 is the set error threshold, which can be an empirical value.

[0026] In this embodiment of the invention, DS10 can be obtained in the following manner:

[0027] When the metal wire is in a normal state, i.e., without any wire breakage or tangling, the drive mechanism of the first eddy current sensor 5 drives the first eddy current sensor 5, which is installed at a set position, to move from one end to the other along the axial direction of the processing roller at a set speed, so as to scan the metal wire on the processing roller multiple times. After completing the i-th scan, the corresponding detection signal set I1 will be obtained. i ={I1 i1 I1 i2 , ..., I1 ij , ..., I1 in}, I1 ij Let be the signal detected by the first eddy current sensor 5 at the j-th scanning position during the i-th scanning process, where i ranges from 1 to m, m is the number of scans corresponding to each scan by the first eddy current sensor 5; and j ranges from 1 to n, where n is the number of scanning positions corresponding to the first eddy current sensor 51. P represents the number of metal wires arranged on the processing roller, and ΔL1 represents the number of metal wires detected per unit by the first eddy current sensor 5, i.e., the number of metal wires that can be scanned at each scanning position is the number of metal wires detected per unit. In this embodiment of the invention, the detection signal can be a voltage.

[0028] In one illustrative embodiment, the total average signal AvgI1 can be obtained. t =(I1) t 1+I1 t 2+……+I1 t i +……+I1 t m ) / m is DS10, where I1 t i Let I1 be the average detection signal corresponding to the i-th scan process. t i =(I1) i1 +I1 i2 +……+I1 ij +……+I1 in ) / n.

[0029] In another embodiment, the average signal AvgI1 at the j-th scan position can be obtained. j =(I1) 1j +I1 2j +……+I1 ij +……+I1 mj Let ) / m be the detection signal threshold corresponding to the j-th scan position. Compared with using the total average signal as the detection signal threshold, using the corresponding average signal as the detection signal threshold for each scan position can make the detection more accurate.

[0030] In another embodiment of the present invention, the application scenario further includes a second eddy current sensor 10, such as... Figure 5 As shown, the second eddy current sensor 10 is disposed between two processing rollers and is used to move along the axial direction of the processing rollers to detect whether the wound metal wire is in an abnormal bending state. Taking three processing rollers as an example, the second eddy current sensor 10 can be disposed between the first processing roller and the second processing roller 4, that is, disposed on the side above the horizontal metal wire, for example, on the left or right side. Figure 4 As shown. The distance between the second eddy current sensor 10 and the metal wire can be determined based on the actual situation; theoretically, the closer the better, as this will make the detection signal more accurate. In one illustrative embodiment, the distance between the second eddy current sensor 10 and the metal wire can be 2 mm.

[0031] Furthermore, the method provided in this embodiment of the invention further includes the following steps:

[0032] S300, when the metal wire is in the traveling state, control the second eddy current sensor to move along the axial direction of the corresponding processing roller at a set speed.

[0033] In this embodiment of the invention, the second eddy current sensor can be driven by a corresponding driving mechanism to move along the axial direction of the processing roller. In this embodiment, the number of metal wires detected per unit of the second eddy current sensor 10, ΔL2 (i.e., the number of metal wires that can be detected each time), can be determined based on actual conditions, as long as the detection accuracy can be ensured. In one illustrative embodiment, ΔL2 can be 10 to 20 wires.

[0034] S400, acquire the detection signal DS2 currently collected by the second eddy current sensor, if The degree of bending of the metal wire wound on the processing roller is determined to be an abnormal degree of bending, and a corresponding prompt signal is output; wherein, DB1 is the first degree of bending detection signal threshold, and DB2 is the second degree of bending detection signal threshold.

[0035] During the processing of a workpiece using metal wire, the metal wire needs to maintain a certain degree of curvature to improve cutting efficiency. In this embodiment of the invention, if the curvature of the metal wire is within a preset range, it indicates that the metal wire is in a normal curvature state; otherwise, it is in an abnormal curvature state. In one illustrative embodiment, the preset range can be [Hmin, Hmax], where Hmin is the preset minimum curvature and Hmax is the preset maximum curvature. In one illustrative embodiment, Hmin = 5mm and Hmax = 10mm. During the movement of the second eddy current sensor, its collected detection signal DS2 is acquired in real time. If... This indicates that the metal wire is in an abnormal bending state, that is, the degree of bending of the metal wire wound on the processing roller is determined to be abnormal.

[0036] In this embodiment of the invention, DB1 and DB2 can be obtained in the following manner:

[0037] When the metal wire is at a preset minimum level, the drive mechanism of the second eddy current sensor 10 drives the second eddy current sensor 10, which is installed at a set position, to move from one end to the other along the axial direction of the processing roller at a set speed, so as to scan the metal wire between the processing rollers multiple times. In this way, after completing the r-th scan, the corresponding detection signal set I2 will be obtained. min r ={I2 min r1 I2 min r2 , ..., I2 min rs , ..., I2 min rg}, I2 min rs Here, is the signal detected by the second eddy current sensor 10 at the s-th scan position during the r-th scan process, where r ranges from 1 to g, g is the number of scans corresponding to each scan by the second eddy current sensor 10, and s ranges from 1 to h, where h is the number of scan positions corresponding to the second eddy current sensor 10. P represents the number of metal lines arranged on the processing roller, and △L1 represents the number of metal lines detected per unit by the second eddy current sensor 10, that is, the number of metal lines that can be scanned at each scanning position is the number of metal lines detected per unit.

[0038] In one illustrative embodiment, the total average signal AvgI2 can be obtained. min t =(I2) min-t 1+I2 min-t 2+……+I2 min-t r +……+I2 min-t g ) / g is used as the threshold signal DB1 for the first degree of bending detection, where I2 min-t r I2 is the average detection signal corresponding to the r-th scan process. min-t r =(I2) min r1 +I2 min r2 +……+I2 min rs +……+I2 min rg) / g.

[0039] In another embodiment, the average signal AvgI2 at the s-th scan position can be obtained. min s =(I2) min 1s +I2 min 2s +……+I2 min rs +……+I2 min gs The value of ) / g is used as the threshold DB1 for detecting the first degree of curvature at the s-th scan position. Compared with using the total average signal as the detection signal threshold, using the corresponding average signal as the detection signal threshold for each scan position makes the detection more accurate.

[0040] When the metal wire is at its preset maximum extent, the drive mechanism of the second eddy current sensor 10 drives the second eddy current sensor 10, which is installed at a set position, to move from one end to the other along the axial direction of the processing roller at a set speed, so as to scan the metal wire between the processing rollers multiple times. In this way, after completing the r-th scan, the corresponding detection signal set I2 will be obtained. max r ={I2 max r1 I2 max r2 , ..., I2 max rs , ..., I2 max rg}, I2 max rs Here, is the signal detected by the second eddy current sensor 10 at the s-th scan position during the r-th scan process, where r ranges from 1 to g, g is the number of scans corresponding to each scan by the second eddy current sensor 10, and s ranges from 1 to h, where h is the number of scan positions corresponding to the second eddy current sensor 10. P represents the number of metal lines arranged on the processing roller, and △L1 represents the number of metal lines detected per unit by the second eddy current sensor 10, that is, the number of metal lines that can be scanned at each scanning position is the number of metal lines detected per unit.

[0041] In one illustrative embodiment, the total average signal AvgI2 can be obtained. max t =(I2) max-t 1+I2 max-t 2+……+I2 max-t r +……+I2 max-t g ) / g is used as the threshold signal DB2 for the second degree of bending detection, where I2max-t r I2 is the average detection signal corresponding to the r-th scan process. max-t r =(I2) max r1 +I2 max r2 +……+I2 max rs +……+I2 max rg ) / g.

[0042] In another embodiment, the average signal AvgI2 at the s-th scan position can be obtained. max s =(I2) max 1s +I2 max 2s +……+I2 max rs +……+I2 max gs DB2 is used as the second bending degree detection signal threshold at the s-th scan position. Compared with using the total average signal as the detection signal threshold, using the corresponding average signal at each scan position as the detection signal threshold makes the detection more accurate.

[0043] It should be noted that S300 and S400 can be executed synchronously or asynchronously.

[0044] Furthermore, in this embodiment of the invention, the application scenario further includes a third eddy current sensor and a fourth eddy current sensor. The third eddy current sensor is disposed on the side of the first vertical guide wheel and is linked to the first vertical guide wheel. The first vertical guide wheel is used to guide the metal wire conveyed by the first wiring roller to a vertical state, and is the first guide wheel for conveying the metal wire conveyed by the first wiring roller, such as... Figure 1 The guide wheel shown in Figure 71. The fourth eddy current sensor is disposed on the side of the second vertical guide wheel and is linked to the second vertical guide wheel. The second vertical guide wheel is used to guide the metal wire conveyed by the second wiring roller to a vertical state, and is the first guide wheel for conveying the metal wire conveyed by the second wiring roller, as shown in Figure 71. Figure 1 The guide wheel shown in 72.

[0045] In this embodiment of the invention, the eddy current sensor and its corresponding vertical guide wheel can share a mounting bracket to achieve linkage.

[0046] In this embodiment of the invention, the third eddy current sensor and the fourth eddy current sensor are used to detect the vertical state of a single metal wire. Hereinafter, the third eddy current sensor and the fourth eddy current sensor are collectively referred to as the metal wire vertical state detection sensor 11. Figure 5 As shown, the front end of the metal wire verticality detection sensor 11, i.e., the third and fourth metal wire detectors, is provided with a protective cover 12. The protective cover is a metal protective cover to prevent the diamond wire from cutting the probe when it breaks. In another illustrative embodiment, the front plug of the metal wire verticality detection sensor 11 can be set as a ceramic front plug, which can also play a protective role.

[0047] In an illustrative embodiment of the present invention, such as Figure 5 As shown, both the third and fourth metal wire detectors have a detection probe; the third eddy current sensor is perpendicular to the first vertical guide wheel, meaning the axis of the third eddy current sensor is perpendicular to the axis of the first vertical guide wheel. Thus, the probe of the third eddy current sensor faces the metal wire, meaning the axis of the third eddy current sensor and the metal wire are in the same plane; the fourth eddy current sensor is perpendicular to the second vertical guide wheel, meaning the axis of the fourth eddy current sensor is perpendicular to the axis of the second vertical guide wheel. Thus, the probe of the fourth eddy current sensor faces the metal wire, meaning the axis of the third eddy current sensor and the metal wire are in the same plane. It should be noted that, to avoid redundancy, Figure 5 This diagram only shows the setup of a metal wire verticality detection sensor. The distance between the sensor and the metal wire can be set according to actual needs, as long as the detection accuracy is ensured.

[0048] Furthermore, the method provided in this embodiment of the invention further includes the following steps:

[0049] S500, when the metal wire is in the traveling state, the detection signals DS3 and DS4 collected by the third eddy current sensor and the fourth eddy current sensor are acquired respectively.

[0050] S600, if |DSp-V0|>0, it is determined that the metal wire being conveyed by the corresponding vertical guide wheel is currently in a skewed state; where p=3 or 4, and V0 is the set vertical state detection signal threshold.

[0051] In this embodiment of the invention, V0 can be determined as follows: when the metal wire is in a vertical state and the metal wire vertical state detection sensor is located at a set position, for example, at a distance of about 1.5 mm from the metal wire, the detection signal of the metal wire vertical state detection sensor at this time is obtained as the vertical state detection signal threshold V0.

[0052] If |DSp-V0| > 0, it means that the metal wire being fed by the corresponding vertical guide wheel is currently in a skewed state. Specifically, if (DSp-V0) > 0, it means that the metal wire is skewed towards the direction closer to the eddy current sensor, i.e., skewed to the left. If (V0-DSp) > 0, it means that the metal wire is skewed away from the eddy current sensor, i.e., skewed to the right. If DSp = V0, it means that the metal wire being fed by the corresponding vertical guide wheel is currently in a vertical state.

[0053] It should be noted that those skilled in the art can also calculate the deflection angle of the metal wire based on trigonometric relationships. Specifically, the vertical distance 'a' between the metal wire vertical state detection sensor and the inlet or outlet point of the wiring roller is known, as is the horizontal distance 'b' between the sensor and the metal wire. The horizontal distance 'bc' between the metal wire and the metal wire vertical state detection sensor can be determined from the detection signal of the metal wire vertical state detection sensor. Thus, the deflection angle θ satisfies: tanθ=(b-bc) / a.

[0054] In this embodiment, the metal wire verticality detection sensor can identify the degree of skew in the direction parallel to the wire wheel plane, but skew in the direction perpendicular to the wire wheel plane will affect the detection accuracy. Furthermore, the probe mounting bracket must move with the wire wheel mounting bracket to form a whole; tilting within the plane perpendicular to the wire wheel will affect the detection accuracy. Therefore, to further improve the detection accuracy, in another embodiment of the invention, the metal wire verticality detection sensor adopts a different structure. The structure of the metal wire verticality detection sensor in this embodiment is basically the same as that of the metal wire verticality detection sensor in the previous embodiment, except that it has three detection probes, such as... Figure 6 As shown, both the third and fourth metal wire detectors have three detection probes: a central detection probe and left and right detection probes respectively positioned on either side of the central detection probe. The third eddy current sensor is arranged parallel to the first vertical guide wheel, meaning its axis lies in a plane parallel to the axis of the first vertical guide wheel. The fourth eddy current sensor is arranged parallel to the second vertical guide wheel, meaning its axis is parallel to the axis of the second vertical guide wheel.

[0055] It should be noted that, to avoid being redundant, Figure 6 This diagram only shows the setup of a metal wire verticality detection sensor. The distance between the sensor and the metal wire can be set according to actual needs, as long as the detection accuracy is ensured.

[0056] Furthermore, the method may also include the following steps:

[0057] S700, when the metal wire is in the traveling state, acquire the detection signal V31 collected by the three detection probes of the current third eddy current sensor. c V32 c and V33 c And to acquire the detection signal V41 collected by the three detection probes of the fourth eddy current sensor. c V42 c and V43 c Among them, V31 c The detection signal currently acquired by the left probe of the third eddy current sensor, V32 c The detection signal currently acquired by the intermediate probe of the third eddy current sensor, V33 c The current detection signal acquired by the right probe of the third eddy current sensor, V41 c The current detection signal acquired by the left probe of the fourth eddy current sensor, V42 c The detection signal currently acquired by the intermediate probe of the fourth eddy current sensor, V43 c This is the detection signal currently collected by the right probe of the fourth eddy current sensor.

[0058] S800, based on Vq1 c Vq2 c Vq3 c And V1, V2 and V3, to determine whether the metal wire currently being conveyed by the wire distribution roller is in a vertical state, where q is equal to 3 or 4, and V1, V2 and V3 are the first set detection signal threshold, the second set detection signal threshold and the third set detection signal threshold, respectively.

[0059] In this embodiment of the invention, V1, V2, and V3 can be obtained in the following manner: when the metal wire is in a vertical state and the metal wire vertical state detection sensor is located at a set position (e.g., when the metal wire is in a vertical state, the metal wire vertical state detection sensor is located at a set position). Figure 6 When the state is shown by the solid line L1 in the figure, the detection signals of the three detection probes of the metal wire vertical state detection sensor are obtained at this time, and are respectively used as the first set detection signal threshold, the second set detection signal threshold and the third set detection signal threshold.

[0060] Furthermore, the S800 may specifically include:

[0061] If V1 c =V1,V2 c =V2,V3 c =V3, confirming the metal wire is in a vertical state; if Vq1 c >V1, Vq2 c <V2, Vq3 c <V3, determine that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the first skew state; if Vq1 c>Vq1, Vq2 c >V2, Vq3 c <V3, determine that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the second skew state; if Vq1 c >V1, Vq2 c >V2, Vq3 c >V3, determine that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the third skew state; if Vq1 c <V1, Vq2 c <V2, Vq3 c >V3, determine that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the fourth skew state; if Vq1 c <V1, Vq2 c <V2, Vq3 c >V3, determine that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the fifth skew state; if Vq1 c <V1, Vq2 c <V2, Vq3 c <V3, and (Vq3) c -V3)<(Vq1 c -V1), determine that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the sixth skew state; if Vq1 c <V1, Vq2 c <V2, Vq3 c <V3, and (Vq3) c -V3)=(Vq1 c -V1), determine that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the seventh skew state; if Vq1 c <V1, Vq2 c <V2, Vq3 c <V3, and (Vq1) c -V1)>(Vq3 c -V3) determines that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the eighth skew state.

[0062] In this embodiment of the invention, the first skew state is the state after the metal wire has shifted from a vertical state to a leftward skew within the plane containing the circumferential surface of the parallel wire distribution roller, i.e., shifted in the direction indicated by arrow a1. Figure 6The states shown by the dashed line L2 on the left are as follows: the second deflection state is when the metal wire deflects from its vertical position in the second quadrant towards the direction closer to the detection probe, i.e., in the direction shown by arrow a2; the third deflection state is when the metal wire deflects from its vertical position in the plane containing the circumference of the vertical distribution roller towards the direction closer to the detection probe, i.e., in the direction shown by arrow a3; the fourth deflection state is when the metal wire deflects from its vertical position in the first quadrant towards the direction closer to the detection probe, i.e., in the direction shown by arrow a4; the fifth deflection state is when the metal wire deflects from its vertical position in the plane containing the circumference of the parallel distribution roller to the right, i.e., in the direction shown by arrow a5. Figure 6 The states shown by the dashed line L3 on the right are as follows: the sixth skew state is when the metal wire deviates from the vertical plane in the fourth quadrant towards the direction away from the detection probe, i.e., it shifts in the direction shown by arrow a6; the seventh skew state is when the metal wire deviates from the vertical plane on the circumferential surface of the vertical distribution roller towards the direction away from the detection probe, i.e., it shifts in the direction shown by arrow a7; and the eighth skew state is when the metal wire deviates from the vertical plane in the third quadrant towards the direction away from the detection probe, i.e., it shifts in the direction shown by arrow a8.

[0063] Furthermore, in another embodiment of the present invention, the metal wire verticality detection sensor adopts a different structure. The structure of the metal wire verticality detection sensor in this embodiment is basically the same as that of the metal wire verticality detection sensor in the aforementioned embodiments, except that it has four detection probes, such as... Figure 7 As shown, both the third and fourth metal wire detectors have four detection probes, including an upper detection probe group and a lower detection probe group. The upper detection probe group includes a first upper detection probe and a second upper detection probe arranged side by side. The lower detection probe group is located below the upper detection probe group and includes a first lower detection probe and a second lower detection probe arranged side by side. The first and second upper detection probes are tangent to each other, as are the first and second lower detection probes. Furthermore, the tangent lines between the first and second upper detection probes and the first and second lower detection probes are collinear, i.e., on the same straight line. Each detection probe has the same shape, but their detection signals are different. Specifically, the detection signal of the second lower detection probe is greater than that of the first lower detection probe, the detection signal of the first lower detection probe is greater than that of the first upper detection probe, and the detection signal of the first upper detection probe is greater than that of the second upper detection probe.

[0064] It should be noted that, to avoid being redundant, Figure 7This diagram only shows the setup of a metal wire verticality detection sensor. The distance between the sensor and the metal wire can be set according to actual needs, as long as the detection accuracy is ensured.

[0065] Furthermore, the method may also include the following steps:

[0066] S810, when the metal wire is in the traveling state, acquire the detection signal V31 collected by the four detection probes of the current third eddy current sensor. c Up to V34 c And to acquire the detection signal V41 collected by the four detection probes of the fourth eddy current sensor. c Up to V44 c Among them, V31 c The detection signal currently acquired by the first upper detection probe of the third eddy current sensor, V32 c The detection signal currently acquired by the second upper detection probe of the third eddy current sensor, V33 c The detection signal currently acquired by the second lower detection probe of the third eddy current sensor, V34 c This is the detection signal currently acquired by the second lower detection probe of the third eddy current sensor; V41 c The detection signal currently acquired by the first upper detection probe of the fourth eddy current sensor, V42 c The detection signal currently acquired by the second upper detection probe of the fourth eddy current sensor, V43 c The detection signal currently acquired by the second lower detection probe of the fourth eddy current sensor, V44 c This is the detection signal currently collected by the second lower detection probe of the fourth eddy current sensor.

[0067] S820, based on V31 c Up to V34 c Get the current position X1 of the first wiring roller. c and based on V41 c Up to V44 c Get the current position X2 of the second wiring roller. c ; where X1 c =((∣V34) c -V33 c |-|V31 c -V32 c ∣)-b1) / k1,X2 c =((∣V44) c -V43 c |-|V41 c -V42 c∣)-b2) / k2; b1 and b2 are the first and second set values, respectively, and k1 and k2 are the first and second set coefficients, respectively.

[0068] In this embodiment of the invention, the position of the vertical guide wheel is the coordinate of the center of the vertical guide wheel on the X-axis in a set rectangular coordinate system. The set rectangular coordinate system can be a custom rectangular coordinate system, such as the world coordinate system.

[0069] In this embodiment of the invention, b1 and k1 can be obtained through the following steps:

[0070] S8201, when the metal wire is in a vertical state (e.g.) Figure 7 When the state is shown by the solid line L in the diagram, and the third eddy current sensor is in the reference state corresponding to the set position, the detection signal V31 collected by the four detection probes of the third eddy current sensor is acquired. 0 Up to V34 0 and the position X1 of the first vertical guide wheel 0 The baseline parameter set P0 = (△C0, X1) is obtained. 0 ), where △C0 is the difference between the reference signals, and △C0=∣V34 0 -V33 0 |-|V31 0 -V32 0 |).

[0071] In this embodiment of the invention, when the metal wire is in a vertical state, the tangent of the metal wire and the detection probe of the third eddy current sensor overlaps in the vertical direction, such as... Figure 7 The solid line L in the diagram is shown.

[0072] S8202, control the first vertical guide wheel to shift to the left from the reference state according to the set offset Δd, until the corresponding metal wire is located at the edge of the first upper detection probe, and obtain the left offset parameter set PL = {PL1, PL2, ..., PL...} r , ..., PL w}, PL r Let r be the r-th parameter group in PL, where r ranges from 1 to w, and w is the number of parameter groups in PL; PL r =(△C L r X1 L r ), △C L r For PL r The corresponding signal difference, ΔC L r =∣V34 L r -V33 Lr |-|V31 L r -V32 L r |), V31 L r Up to V34 L r X1 represents the detection signals from the four probes of the third eddy current sensor after the first vertical guide wheel has shifted to the left for the rth time. L r This is to control the position of the first vertical guide wheel after it shifts to the left for the rth time. △d can be set based on actual needs, for example, 1–2 mm.

[0073] S8203 controls the first vertical guide wheel to shift to the right from the reference state according to the set offset Δd until the corresponding metal wire is located at the edge of the second upper detection probe, thus obtaining the right offset parameter set PR = {PR1, PR2, ..., PR...} r ... PR w}, PR r Let r be the r-th parameter set in PR, where r ranges from 1 to w, and w is the number of parameter sets in PR; r =(△C R r X1 R r ), △C R r For PR r The corresponding signal difference, ΔC R r =∣V34 R r -V33 R r |-|V31 R r -V32 R r |), V31 R r Up to V34 R r X1 represents the detection signals from the four probes of the third eddy current sensor after the first vertical guide wheel has shifted to the right for the rth time. R r To control the position of the first vertical guide wheel after it shifts to the right for the rth time.

[0074] S8204 uses the signal difference of each parameter group as the vertical axis and the position of the vertical guide wheel as the horizontal axis to plot the corresponding relationship curve, thus obtaining the signal difference-position curve.

[0075] S8205, obtain the curve that satisfies the linear relationship in the signal difference-position curve as the reference curve, and fit the obtained reference curve to obtain the signal difference-position relationship Y1=k1×X1+b1, where Y1 is the signal difference and X1 is the position of the first vertical guide wheel.

[0076] As those skilled in the art will know, b2 and k2 can be obtained by referring to the methods used to obtain b1 and k1. To avoid redundancy, the present invention omits a detailed description of them.

[0077] S830, if X1 c >X1 0 It is determined that the metal wire conveyed by the first wiring roller is in a left-biased state, if X1 c <X1 0 It is determined that the metal wire conveyed by the first wiring roller is in a right-biased state; if X2 c >X2 0 If X2 c <X2 0 It is determined that the metal wire conveyed by the second wiring roller is in a right-biased state; X1 0 X2 represents the position of the first wire-distributing roller when the conveyed metal wire is in a vertical state. 0 This refers to the position of the second wire distribution roller when the conveyed metal wire is in a vertical state.

[0078] Furthermore, the method also includes the following steps:

[0079] S840, if |X1 c -X1 0 |>X1 m , or |X2 c -X2 0 |>X2 m It outputs an alarm signal indicating that the metal wire is deviated too much.

[0080] Among them, X1 m X2 is the alarm position threshold corresponding to the first vertical guide wheel. m This is the alarm position threshold corresponding to the second vertical guide wheel. X1 m To correspond to the position of the first vertical guide wheel when the metal wire is located at the center line of the first upper detection probe of the third eddy current sensor, X2 m The position of the second vertical guide wheel is corresponding to the position of the metal wire located at the center line of the first upper detection probe of the fourth eddy current sensor.

[0081] Furthermore, the method provided in this embodiment of the invention further includes the following steps:

[0082] S900, when the metal wire is detected to be in a skewed state, the corresponding vertical guide wheel is controlled to perform a corresponding operation so that the metal wire is in a vertical state.

[0083] Those skilled in the art will understand that when it is determined that the metal wire is in a deflected state, the distance and direction that the corresponding vertical guide wheel needs to move can be determined based on the signal detected by the eddy current sensor, thereby controlling the corresponding vertical guide wheel to perform corresponding operations based on the determined distance and direction of movement. Any method for determining the distance and direction that the corresponding vertical guide wheel needs to move based on the signal detected by the eddy current sensor falls within the protection scope of this application. For example, with Figure 7 Taking the structure shown as an example, if X1 c >X1 0 Control the first vertical guide wheel to shift to the right (X1) c -X1 0 The corresponding offset is sufficient.

[0084] Those skilled in the art know that if the metal wire is in a vertical state, the force is minimal, thereby improving the service life of the metal wire. Therefore, the embodiments of the present invention detect the vertical state of the metal wire, and when a non-vertical state is detected, the position of the wiring roller is adjusted in time to make the metal wire vertical, thereby avoiding the problem of excessive force due to skew.

[0085] In this embodiment of the invention, the above method can be implemented by a processor, which is communicatively connected to the processing roller, the wiring roller, the eddy current sensor, the drive unit, etc.

[0086] As those skilled in the art will know, the application scenarios involved in the embodiments of the present invention may also include other structures of existing cutting equipment, such as frames.

[0087] In summary, the metal wire state detection method provided by the embodiments of the present invention can detect abnormal states of the metal wire in real time during the movement of the metal wire, thus improving the processing quality of the workpiece when applied in a processing scenario.

[0088] While specific embodiments of the invention have been described in detail by way of example, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of the invention. Those skilled in the art should also understand that various modifications can be made to the embodiments without departing from the scope and spirit of the invention. The scope of this invention is defined by the appended claims.

Claims

1. A method for detecting the state of a metal wire, characterized in that, This method is used to detect abnormal states of a traveling metal wire. The application scenarios include at least: a first wiring roller, a second wiring roller, a first wiring roller drive unit, a second wiring roller drive unit, at least two parallel processing rollers, a processing roller drive unit, and a first eddy current sensor. The first eddy current sensor is disposed on the side of any one of the at least two processing rollers. The metal wire is wound around the at least two processing rollers, with one end connected to the first wiring roller and the other end connected to the second wiring roller. The first wiring roller and the second wiring roller rotate under the drive of the first wiring roller drive unit and the second wiring roller drive unit, respectively, so that the metal wire travels between the first wiring roller and the second wiring roller and wound around the at least two processing rollers driven by the processing roller drive unit. The method includes the following steps: S100, when the metal wire is in the traveling state, control the first eddy current sensor to move along the axial direction of the corresponding processing roller at a set speed; S200: Acquire the detection signal DS1 collected by the first eddy current sensor, and determine whether the metal wire wound on the processing roller is in an abnormal state based on DS1 and DS10; wherein, if (DS1-DS10)>d0, it is determined that the metal wire wound on the processing roller is in a parallel state, and if (DS10-DS1)>d0, it is determined that the metal wire wound on the processing roller is in a broken state, and a corresponding prompt signal is output; DS10 is the detection signal threshold corresponding to DS1, and d0 is the set error threshold; The application scenario also includes a third eddy current sensor and a fourth eddy current sensor. The third eddy current sensor is disposed on the side of the first vertical guide wheel and is linked to the first vertical guide wheel, which guides the metal wire conveyed by the first wiring roller to a vertical position. The fourth eddy current sensor is disposed on the side of the second vertical guide wheel and is linked to the second vertical guide wheel, which guides the metal wire conveyed by the second wiring roller to a vertical position. Both the third and fourth eddy current sensors have three or four detection probes. The third eddy current sensor is arranged parallel to the first vertical guide wheel; the fourth eddy current sensor is arranged parallel to the second vertical guide wheel. When there are three detection probes, including a middle detection probe and a left detection probe and a right detection probe respectively disposed on both sides of the middle detection probe; the method further includes: S700, when the metal wire is in the traveling state, acquire the detection signal V31 collected by the three detection probes of the third eddy current sensor. c V32 c and V33 c And to acquire the detection signal V41 collected by the three detection probes of the fourth eddy current sensor. c V42 c and V43 c Among them, V31 c The detection signal currently acquired by the left probe of the third eddy current sensor, V32 c The detection signal currently acquired by the intermediate probe of the third eddy current sensor, V33 c The current detection signal acquired by the right probe of the third eddy current sensor, V41 c The current detection signal acquired by the left probe of the fourth eddy current sensor, V42 c The detection signal currently acquired by the intermediate probe of the fourth eddy current sensor, V43 c This is the detection signal currently collected by the right probe of the fourth eddy current sensor; S800, based on Vq1 c Vq2 c Vq3 c And V1, V2 and V3, determine whether the metal wire currently being conveyed by the vertical guide wheel is in a vertical state, where q is equal to 3 or 4, and V1, V2 and V3 are the first set detection signal threshold, the second set detection signal threshold and the third set detection signal threshold, respectively; When four detection probes are used, including an upper detection probe group and a lower detection probe group, the upper detection probe group includes a first upper detection probe and a second upper detection probe arranged side by side, and the lower detection probe group is located below the upper detection probe group, including a first lower detection probe and a second lower detection probe arranged side by side; the method further includes: S810, when the metal wire is in the traveling state, acquire the detection signal V31 collected by the four detection probes of the current third eddy current sensor. c Up to V34 c And to acquire the detection signal V41 collected by the four detection probes of the fourth eddy current sensor. c Up to V44 c Among them, V31 c The detection signal currently acquired by the first upper detection probe of the third eddy current sensor, V32 c The detection signal currently acquired by the second upper detection probe of the third eddy current sensor, V33 c The detection signal currently acquired by the second lower detection probe of the third eddy current sensor, V34 c This is the detection signal currently acquired by the second lower detection probe of the third eddy current sensor; V41 c The detection signal currently acquired by the first upper detection probe of the fourth eddy current sensor, V42 c The detection signal currently acquired by the second upper detection probe of the fourth eddy current sensor, V43 c The detection signal currently acquired by the second lower detection probe of the fourth eddy current sensor, V44 c This is the detection signal currently acquired by the second lower detection probe of the fourth eddy current sensor; S820, based on V31 c Up to V34 c Get the current position X1 of the first wiring roller. c and based on V41 c Up to V44 c Get the current position X2 of the second wiring roller. c ; where X1 c =((∣V34 c -V33 c |-|V31 c -V32 c |)-b1) / k1,X2 c =((∣V44 c -V43 c |-|V41 c -V42 c |)-b2) / k2; b1 and b2 are the first and second set values, respectively, and k1 and k2 are the first and second set coefficients, respectively; S830, if X1 c >X1 0 If X1 c <X1 0 It is determined that the metal wire conveyed by the first vertical guide wheel is in a right-biased state; if X2 c >X2 0 If X2 c <X2 0 It is determined that the metal wire conveyed by the second vertical guide wheel is in a right-biased state; X1 0 X2 represents the position of the first vertical guide wheel when the conveyed metal wire is in a vertical state. 0 This refers to the position of the second vertical guide wheel when the conveyed metal wire is in a vertical state.

2. The method according to claim 1, characterized in that, The application scenario also includes a second eddy current sensor, which is disposed between two processing rollers; the method further includes: S300, when the metal wire is in the traveling state, control the second eddy current sensor to move along the axial direction of the corresponding processing roller at a set speed; S400, acquire the detection signal DS2 collected by the second eddy current sensor. If DS2∉[DB1, DB2], determine that the bending degree of the metal wire wound on the processing roller is an abnormal bending degree, and output the corresponding prompt signal; where DB1 is the first bending degree detection signal threshold and DB2 is the second bending degree detection signal threshold.

3. The method according to claim 1, characterized in that, The S800 specifically includes: If Vq1 c >V1, Vq2 c <V2, Vq3 c <V3, it is determined that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the first skew state; If Vq1 c >Vq1, Vq2 c >V2, Vq3 c <V3, indicating that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the second skew state; If Vq1 c >V1, Vq2 c >V2, Vq3 c >V3, confirming that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the third skew state; If Vq1 c <V1, Vq2 c <V2, Vq3 c >V3, confirming that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the fourth skew state; If Vq1 c <V1, Vq2 c <V2, Vq3 c >V3, confirming that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the fifth skew state; If Vq1 c <V1, Vq2 c <V2, Vq3 c <V3, and (Vq3) c -V3) < (Vq1) c -V1), which determines that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the sixth skew state; If Vq1 c <V1, Vq2 c <V2, Vq3 c <V3, and (Vq3) c -V3) = (Vq1) c -V1), which determines that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the seventh skew state; If Vq1 c <V1, Vq2 c <V2, Vq3 c <V3, and (Vq1) c -V1) > (Vq3) c -V3), determine that the metal wire being conveyed by the corresponding vertical guide wheel is currently in the eighth skew state; The first deflection state is when the metal wire deflects to the left from its vertical position within the plane containing the circumferential surface of the parallel wiring roller; the second deflection state is when the metal wire deflects towards the detection probe from its vertical position within the second quadrant; the third deflection state is when the metal wire deflects towards the detection probe from its vertical position within the plane containing the circumferential surface of the vertical wiring roller; the fourth deflection state is when the metal wire deflects towards the detection probe from its vertical position within the first quadrant; the fifth deflection state is when the metal wire deflects to the right from its vertical position within the plane containing the circumferential surface of the parallel wiring roller; the sixth deflection state is when the metal wire deflects away from the detection probe from its vertical position within the fourth quadrant; the seventh deflection state is when the metal wire deflects away from the detection probe from its vertical position within the plane containing the circumferential surface of the vertical wiring roller; and the eighth deflection state is when the metal wire deflects away from the detection probe from its vertical position within the third quadrant.

4. The method according to any one of claims 1 to 3, characterized in that, It also includes the following steps: S900, when the metal wire is detected to be in a skewed state, the corresponding vertical guide wheel is controlled to perform a corresponding operation so that the metal wire is in a vertical state.

5. The method according to any one of claims 1 to 3, characterized in that, The front ends of the third eddy current sensor and the fourth eddy current sensor are provided with protective covers.

6. The method according to claim 1, characterized in that, The metal wire is diamond wire.

7. The method according to claim 1, characterized in that, The application scenario also includes the workpiece being processed; the metal wire wound on the processing roller is used to cut the workpiece when the processing roller is in a driving state.

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