Metal detection system and method with partition detection function

Abstract

The invention provides a metal detection system and method with a partition detection function. The metal detection system comprises a conveying device which is provided with a conveying frame and a conveying belt arranged on the conveying frame; the metal detector comprises a shell located on the conveying frame and a detector arranged in the shell, the detector is provided with a transmitting assembly and a receiving assembly, in the width direction of the conveying belt, the transmitting assembly forms an annular transmitting area, and the receiving assembly forms an independent detection area and a composite detection area corresponding to the annular transmitting area; wherein in response to the movement of the conveyor belt, the detector is used for determining the positions of the metal foreign matters passing through the annular emission area, the independent detection area and the composite detection area in the materials on the conveyor belt. According to the invention, the position of the metal foreign matter in the material is rapidly and accurately positioned, the accuracy and reliability of detection are improved, and the subsequent targeted treatment on the material containing the metal foreign matter is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of metal detection equipment, and in particular to a metal detection system and method with a partition detection function. Background Art

[0002] With the development of modern industry, metal detection technology has been widely used in various fields, especially in industries such as food safety, mineral development, and material sorting. Traditional metal detection equipment mainly works based on the eddy current principle. That is, the transmitting coil generates an alternating magnetic field. When a metal object enters this field, eddy currents are generated, which in turn change the surrounding magnetic field. This change is captured by the receiving coil, thus achieving detection.

[0003] However, while traditional metal detection equipment can detect metal foreign matter in materials to a certain extent, most of them have certain limitations. These traditional devices have deficiencies in detection accuracy, positioning accuracy, and the ability to adapt to different materials and production environments. For example, many metal detection systems can only perform a relatively rough inspection of the material as a whole and cannot accurately determine the specific location of the metal foreign matter in the material. This makes it difficult to efficiently remove the metal foreign matter during subsequent processing, often requiring shutdown for manual inspection, which greatly reduces production efficiency. In addition, traditional metal detectors have low detection sensitivity for metal foreign matter with irregular shapes and small sizes, or metal foreign matter in complex material environments (such as materials containing multiple different materials and substances of similar colors), and are prone to missed detections. They cannot meet the requirements of modern industrial production for high-precision and high-reliability metal detection.

[0004] In view of this, the existing technology needs to be further improved and enhanced. Summary of the Invention

[0005] In view of the above problems, the present invention provides a metal detection system and method with a partitioned detection function. By setting up a ring-shaped transmitting area, an independent detection area and a composite detection area formed by the transmitting component and the receiving component in the metal detector, accurate detection of the position of metal foreign objects in the material in the width direction of the conveyor belt can be achieved.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] In a first aspect, the present invention provides a metal detection system with a partition detection function, comprising:

[0008] A conveying device comprising a conveying frame and a conveyor belt arranged on the conveying frame;

[0009] The metal detector comprises a housing located on a conveyor frame and a detector disposed inside the housing. The detector comprises a transmitting assembly and a receiving assembly. Along the width direction of the conveyor belt, the transmitting assembly forms an annular transmitting area, and the receiving assembly forms an independent detection area and a composite detection area corresponding to the annular transmitting area.

[0010] In response to the movement of the conveyor belt, the detector is used to determine the position of the metal foreign matter in the material on the conveyor belt passing through the annular emission area, the independent detection area and the composite detection area.

[0011] Furthermore, the transmitting component has multiple transmitting coils nested in each other, the receiving component has multiple receiving coils partially overlapping each other, and the annular transmitting area is the area formed by the alternating magnetic field generated by the multiple transmitting coils, the independent detection area is the area formed by the non-overlapping parts between the multiple receiving coils for inducing changes in the alternating magnetic field, and the composite detection area is the area formed by the overlapping parts between the multiple receiving coils for inducing changes in the alternating magnetic field.

[0012] Furthermore, the multiple transmitting coils are configured to be located in a first plane parallel to the horizontal direction, and the multiple receiving coils are configured to be located in a second plane parallel to the horizontal direction; wherein the first plane and the second plane are the same plane, or the first plane and the second plane are different parallel planes.

[0013] Furthermore, the area of the overlapping portion between two adjacent receiving coils is between 1 / 5 and 4 / 5.

[0014] Furthermore, two adjacent transmitting coils have the same winding direction but different numbers of winding turns, while two adjacent receiving coils have different winding directions but the same number of winding turns; or, two adjacent transmitting coils have the same winding direction but different numbers of winding turns, while two adjacent receiving coils have different winding directions and different numbers of winding turns; or, two adjacent transmitting coils have different winding directions and different numbers of winding turns, while two adjacent receiving coils have different winding directions and the same number of winding turns; or, two adjacent transmitting coils have different winding directions and different numbers of winding turns, while two adjacent receiving coils have different winding directions and different numbers of winding turns.

[0015] Furthermore, a first shielding layer is provided between two adjacent transmitting coils, and a second shielding layer is provided between two adjacent receiving coils.

[0016] Furthermore, the metal detection system further includes a cutting device provided on the conveyor frame, the cutting device including:

[0017] X-axis translation components are arranged on both sides of the conveyor frame along the length direction of the conveyor belt;

[0018] The Y-axis translation assembly cooperates with the X-axis translation assembly along the width direction of the conveyor belt and is located above the conveyor frame;

[0019] The Z-axis translation assembly cooperates with the Y-axis translation assembly in the vertical direction and has a rotating cutter capable of contacting the material.

[0020] Furthermore, the X-axis translation assembly includes horizontal guide rails respectively arranged on both sides of the conveying frame and first sliders respectively matched with the horizontal guide rails, and a first driving unit for driving the first slider to move along the horizontal guide rails; the Y-axis translation assembly includes a transverse guide rail connected to the first slider and a second slider matched with the transverse guide rails, and a second driving unit for driving the second slider to move along the transverse guide rails; the Z-axis translation assembly includes a fixed seat connected to the second slider, a vertical guide rail arranged on the fixed seat, a third slider matched with the vertical guide rail, a cutting seat connected to the third slider and used to fix the rotary cutter, and a third driving unit for driving the third slider to move along the vertical guide rail.

[0021] Furthermore, the metal detection system also includes a winding device respectively arranged on both sides of the conveying device, and the winding device includes: a mounting frame; a pressure roller arranged on the mounting frame; and a fourth drive unit connected to the pressure roller, and under the drive of the fourth drive unit, the pressure roller can rotate relative to the mounting frame to reel in the material on the conveying device.

[0022] In a second aspect, the present invention further provides a metal detection method with a partition detection function, which is applied to the above metal detection system and comprises the following steps:

[0023] Under the conveying device, the material can move along the length of the conveyor belt;

[0024] In response to the connection with the external high-frequency alternating current, the metal detector starts to work, and the transmitting component and the receiving component in the detector respectively form a ring-shaped transmitting area, an independent detection area and a composite detection area;

[0025] When the material is transported to the annular launch area by the conveyor belt, the alternating magnetic field generated by the launch component acts on the metal foreign matter at different positions in the material to form different eddy currents;

[0026] Different eddy currents form different induced magnetic fields, and the different induced magnetic fields can act on the independent detection area and / or the composite detection area in the receiving component respectively, and cause the receiving component to generate magnetic field signals corresponding to the independent detection area and / or the composite detection area;

[0027] According to the received magnetic field signal, the specific location of the metal foreign matter in the material is determined.

[0028] Due to the adoption of the above technical solution, the technical effects achieved by the present invention are as follows:

[0029] On the one hand, the metal detection system with a partitioned detection function provided by the present invention includes a conveying device and a metal detector. The metal detector includes a shell and a detector, and the detector has a transmitting component and a receiving component. Specifically, the annular transmitting area formed by the transmitting interval, and the independent detection area and the composite detection area formed by the receiving component are set up, so that the detector can perform partitioned detection on materials at different positions in the width direction of the conveyor belt. For example, when the material passes through the annular transmitting area, the alternating magnetic field generated by the transmitting coil covers the entire width of the conveyor belt, while the independent detection area (non-overlapping area) and the composite detection area (overlapping area) of the receiving coil can respectively sense the magnetic field changes in different areas. By combining the conveyor belt movement speed and the timing analysis of the signal, the horizontal (width direction) and longitudinal (conveying direction) positions of the metal foreign matter in the material can be dynamically determined, thereby realizing rapid and accurate positioning of the metal foreign matter position, improving the accuracy and reliability of the detection, and facilitating the subsequent targeted treatment of the material containing the metal foreign matter. In addition, the annular emission area can ensure that the magnetic field evenly covers the material, and the combined design of the independent detection area and the composite detection area expands the effective detection range of metal foreign matter. At the same time, through the comparative analysis of signal superposition (composite detection area) and independent signals (independent detection area), the size and burial depth of metal foreign matter can be distinguished, further improving the detection sensitivity of the equipment.

[0030] On the other hand, the metal detection method with partition detection function provided by the present invention realizes the rapid and accurate detection and positioning of metal foreign matter in materials, effectively improves the efficiency and accuracy of metal detection, and provides reliable technical support for the quality control and safety assurance of materials in industrial production, which helps to reduce production costs, improve product quality and production efficiency.

[0031] The above description is only an overview of the technical solutions of the embodiments of the present invention. In order to more clearly understand the technical means of the embodiments of the present invention, they can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiments of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are specifically listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are only used to illustrate the embodiments and are not to be considered as limiting the present invention. In addition, the same reference symbols are used to represent the same components throughout the drawings. In the drawings:

[0033] Figure 1 It is a structural schematic diagram of a metal detection system provided by the present invention;

[0034] Figure 2 is a side view of a metal detection system provided by the present invention;

[0035] Figure 3 This is a structural diagram of a launch assembly provided by the present invention;

[0036] Figure 4 It is a structural schematic diagram of a receiving component provided by the present invention;

[0037] Figure 5 It is a structural schematic diagram of another metal detection system provided by the present invention;

[0038] Figure 6 It is a structural schematic diagram of a cutting device provided by the present invention;

[0039] Figure 7 It is a structural schematic diagram of another cutting device provided by the present invention;

[0040] Figure 8 It is a structural schematic diagram of another cutting device provided by the present invention;

[0041] Figure 9 It is a structural schematic diagram of another metal detection system provided by the present invention.

[0042] Reference numerals:

[0043] 100 conveying device, 110 conveying rack, 120 conveyor belt;

[0044] 200 metal detector, 210 housing, 220 transmitting assembly, 221 transmitting coil, 230 receiving assembly, 231 receiving coil;

[0045] 300 cutting device, 310 X-axis translation assembly, 311 horizontal guide rail, 312 first slider, 320 Y-axis translation assembly, 321 transverse guide rail, 322 second slider, 323 second drive unit, 330 Z-axis translation assembly, 331 rotary cutter, 332 fixing base, 333 vertical guide rail, 334 third slider, 335 cutting base, 336 third drive unit;

[0046] 400 reeling device, 410 mounting frame, 420 pressure roller. DETAILED DESCRIPTION

[0047] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0048] A metal detector is an electronic instrument that uses the principle of electromagnetic induction to detect metal. It is widely used in mining, cement, coal preparation, thermal power generation, metallurgy, chemicals, papermaking, forestry, environmental protection, and building materials. Based on their signal acquisition, comparison, and analysis methods, metal detectors can be categorized as single-coil and balanced-coil metal detectors. Balanced-coil metal detectors typically contain three coils: a transmitting coil and two receiving coils of equal area. An oscillator connected to the transmitting coil generates a high-frequency variable magnetic field. In the idle state, the induced voltages in the two receiving coils cancel each other out, achieving equilibrium, unless the magnetic field is disturbed. Once a metallic foreign object enters the magnetic field, this equilibrium is disrupted, and the induced voltages in the two receiving coils no longer cancel each other out. The remaining induced voltages are amplified by the control circuit and generate an alarm signal, effectively detecting the metallic foreign object.

[0049] Different models of balanced coil metal detectors have different internal detection coil distribution methods. For example, in one model of metal detector, the two receiving coils are located directly above or below the transmitting coil; in another model of metal detector, the two receiving coils are located on either side of the transmitting coil; and in another model of metal detector, the two receiving coils can be located in the same plane as the transmitting coil, and both receiving coils are located inside the transmitting coil.

[0050] Regardless of the aforementioned metal detector model, due to limitations in the distribution of the detection coils, most are only able to perform metal detection on materials within the overall detection area formed by the detection coils. In other words, because the detection area formed by the aforementioned detection coils is substantially equal to the projected area of the detection coils (or transmitting coils, or receiving coils), when materials on the conveyor belt enter this detection area, while metal foreign matter mixed in the materials can be promptly detected, the specific location of the metal foreign matter across the width of the conveyor belt cannot be further detected. In other words, existing metal detectors are unable to further accurately detect the exact location of metal foreign matter across the width of the conveyor belt.

[0051] The existence of the above-mentioned problems often leads to the need for frequent shutdowns in the actual production process to remove metal foreign matter mixed in the material, which seriously affects the production and processing efficiency. Especially in the detection process of waste rubber materials, the compacted rubber material is in a strip-like structure, and a winding device needs to be set at the end of the strip rubber to wind it up. If the existing metal detector is used for detection during the winding process of the strip rubber, once the presence of metal foreign matter is detected, the machine needs to be shut down first, and then manual assistance is required to check the specific location of the metal foreign matter in the strip rubber. The strip rubber containing the metal foreign matter must be removed by a cutter or other equipment before the equipment can continue to work. It can be seen that the existing metal detector cannot timely and accurately identify the metal foreign matter mixed in the strip rubber, which will greatly affect the subsequent processing efficiency of the strip rubber.

[0052] In view of this, refer to Figure 1-Figure 4 As shown, the present invention provides a metal detection system with a partition detection function, including a conveying device 100 and a metal detector 200. Specifically, the conveying device 100 has a conveying frame 110 and a conveyor belt 120 arranged on the conveying frame 110; the metal detector 200 includes a shell 210 located on the conveying frame 110 and a detector (not marked in the figure) arranged inside the shell 210, and the detector has a transmitting component 220 and a receiving component 230. Along the width direction of the conveyor belt 120, the transmitting component 220 forms an annular transmitting area, and the receiving component 230 forms an independent detection area and a composite detection area corresponding to the annular transmitting area. In response to the movement of the conveyor belt 120, the detector is used to determine the position of metal foreign matter in the material on the conveyor belt 120 that passes through the annular transmitting area, the independent detection area and the composite detection area.

[0053] It should be noted that the conveyor frame 110 in the conveyor device 100 provided by the present invention provides a stable support structure for the conveyor belt 120, which is responsible for carrying the material and conveying it along its length. In practical applications, the conveyor belt 120 can be selected with appropriate size and material based on the characteristics of the material and the requirements of the production process. For example, in the field of ore sorting, a more wear-resistant conveyor belt 120 can be selected, and a motor-driven roller can be used to drive the conveyor belt 120 to operate stably at a set speed, transporting the material sequentially to the detection area of the metal detector 200.

[0054] Regarding the specific structure of the shell 210 in the metal detector 200, the present application can be implemented in a variety of different ways. In one way, the shell 210 can adopt a frame structure, and the frame shell has a cavity for the conveyor belt 120 to pass through. The transmitting component 220 and the receiving component 230 in the detector can be respectively arranged on the upper frame beam and the lower frame beam of the shell; in another way, the shell 210 can adopt a flat plate structure, and the flat plate shell can be arranged below the conveyor belt 120, and the transmitting component 220 and the receiving component 230 in the detector are jointly arranged in the flat plate shell.

[0055] It should also be noted that the annular emission zone formed by the transmitting assembly 220 refers to an area centered on the transmitting assembly 220 and in the surrounding space where the alternating magnetic field strength generated by the transmitting assembly 220 reaches or exceeds a preset magnetic field strength threshold; the preset magnetic field strength threshold is used to ensure that when a metal object enters this area, eddy currents of sufficient strength can be generated in the metal object. Alternatively, the annular emission zone refers to an area where the alternating magnetic field generated by the transmitting assembly 220 at its operating frequency can effectively cover and act on the surrounding space, specifically a three-dimensional spatial area extending outward from the surface of the transmitting assembly 220 to the point where the magnetic field strength decays to a specific ratio (such as 1 / e of the initial magnetic field strength or other ratio set according to detection requirements).

[0056] The independent detection zone and composite detection zone formed by the receiving assembly 230 are determined based on the overlapping areas between the multiple receiving coils 231 in the receiving assembly 230. The area formed by the non-overlapping portions of the multiple receiving coils 231 used to sense the alternating magnetic field is defined as the independent detection zone, while the area formed by the overlapping portions of the multiple receiving coils 231 used to sense the alternating magnetic field is defined as the composite detection zone. Both the independent detection zone and the composite detection zone refer to the region in space where, when a metal object is within this region, the magnetic field changes generated by the eddy currents in the metal object can induce a signal exceeding a set induced electromotive force threshold in the receiving assembly 230; alternatively, they refer to the region in the space surrounding the receiving assembly 230 that has detection sensitivity to the eddy current magnetic field changes generated by the metal object. This region can be represented as a spatial range centered on the receiving assembly 230, with its boundaries determined by the maximum detection range of the receiving assembly 230 for metal objects of a specific size and material at a given detection sensitivity. Within this region, the receiving assembly 230 can effectively receive and respond to magnetic field disturbances caused by the metal object.

[0057] To better understand the present invention, the working principle of the metal detection system provided by the present application is described below:

[0058] First, the material is placed on the conveyor belt 120 of the conveying device 100. As the conveyor belt 120 starts, the material begins to move along the length direction of the conveyor belt 120. The conveyor frame 110 of the conveying device 100 provides stable support for the conveyor belt 120 and the material, ensuring that the material can smoothly enter the metal detection area.

[0059] Secondly, when the material enters the detection range of the metal detector 200, the transmitting component 220 starts working. The transmitting component 220 includes multiple transmitting coils 221 nested in each other. When these transmitting coils 221 are energized, they will generate an alternating magnetic field, thereby forming an annular transmitting area in the width direction of the conveyor belt 120; the material continues to move along the conveyor belt 120. When the material containing metal foreign matter passes through the annular transmitting area, the metal foreign matter will generate eddy currents under the action of the alternating magnetic field. These eddy currents will form a new induced magnetic field. The multiple receiving coils 231 in the receiving component 230 are responsible for sensing these changing magnetic fields. Among them, the independent detection area is formed by the non-overlapping parts between the receiving coils 231, which is used to independently sense the changes in the alternating magnetic field; the composite detection area is formed by the overlapping parts between the receiving coils 231, which is used to simultaneously sense the changes in the alternating magnetic field in the coverage area of multiple receiving coils 231.

[0060] Finally, receiving coil 231 converts the sensed magnetic field changes into electrical signals. After preprocessing through amplification and filtering, these signals are transmitted to the signal processing unit. The signal processing unit uses a specific algorithm to analyze the received signal characteristics, combined with the signal differences between the independent detection area and the combined detection area, to determine the specific location of the metal foreign matter in the material.

[0061] In some embodiments, reference Figure 3 and Figure 4 As shown, the transmitting component 220 has multiple transmitting coils 221 nested with each other, and the receiving component 230 has multiple receiving coils 231 partially overlapping with each other, and the annular transmitting area is the area formed by the alternating magnetic field generated by the multiple transmitting coils 221, the independent detection area is the area formed by the non-overlapping part between the multiple receiving coils 231 for inducing the change of the alternating magnetic field, and the composite detection area is the area formed by the overlapping part between the multiple receiving coils 231 for inducing the change of the alternating magnetic field.

[0062] The use of multiple nested transmitting coils 221 and partially overlapping receiving coils 231 not only enhances the generation and induction of the alternating magnetic field, but also cleverly creates independent and composite detection zones. This coil layout allows the detector to cover a wider detection area, improving detection efficiency. Furthermore, the presence of independent and composite detection zones enables the detector to perform a more comprehensive and detailed analysis of the eddy currents and induced magnetic fields generated by metal foreign objects, further improving detection accuracy and the ability to identify different types of metal foreign objects.

[0063] It should be noted that this application does not limit the specific number of transmitter coils 221 and receiver coils 231. Users can reasonably adjust the number based on different detection requirements, the specific application scenarios of the equipment, and the size specifications. For example, there can be three transmitter coils 221 and three receiver coils 231, and the three transmitter coils 221 are nested within each other, and the three receiver coils 231 partially overlap.

[0064] In some embodiments, the plurality of transmitting coils 221 are configured to be located in a first plane parallel to the horizontal direction, and the plurality of receiving coils 231 are configured to be located in a second plane parallel to the horizontal direction; wherein the first plane and the second plane are the same plane, or the first plane and the second plane are different parallel planes.

[0065] The transmitting coil 221 and receiving coil 231 are respectively arranged in a first plane and a second plane parallel to the horizontal direction, and the two planes can overlap or be parallel. This design helps optimize the structural layout of the detector, ensure the uniformity and stability of the magnetic field, and minimize magnetic field direction distortion. When the first plane and the second plane overlap, efficient interaction between the transmitting and receiving magnetic fields within the same plane can be achieved, enhancing the strength and consistency of the detection signal. When the two planes are parallel, the orderly transmission and reception of the magnetic field can be guaranteed to a certain extent, reducing magnetic field distortion and interference, thereby improving the detector's sensitivity and accuracy in detecting metal foreign objects.

[0066] Furthermore, this configuration of multiple transmitting coils 221 and multiple receiving coils 231 is compatible with metal detector housings 210 having different structures. When the first and second planes are coplanar, the structure of the transmitting assembly 220 and receiving assembly 230 is more compatible with flat-panel metal detectors 200. When the first and second planes are parallel, the structure of the transmitting assembly 220 and receiving assembly 230 is more compatible with frame-type metal detectors 200.

[0067] In some embodiments, the area of the overlapping portion between two adjacent receiving coils 231 is between 1 / 5 and 4 / 5. Preferably, the area of the overlapping portion between two adjacent receiving coils 231 is 1 / 3.

[0068] By limiting the overlapping area between two adjacent receiving coils 231 to between 1 / 5 and 4 / 5, the coverage and detection accuracy of the detection area can be effectively balanced. If the overlapping area is too small, gaps may appear in the detection area, making some metal foreign objects undetectable; while too large an overlapping area will increase signal interference and reduce detection efficiency. Keeping the overlapping area within this reasonable range ensures that there is sufficient overlap between adjacent receiving coils 231 to form a stable composite detection area, achieving cross-detection and accurate positioning of metal foreign objects, while also avoiding excessive signal interference, ensuring that the receiving component 230 can clearly sense the different types and intensities of induced magnetic fields generated by metal foreign objects, thereby improving the performance of the entire detection system.

[0069] In some embodiments, two adjacent transmitting coils 221 have the same winding direction but different numbers of winding turns, while two adjacent receiving coils 231 have different winding directions but the same number of winding turns; or, two adjacent transmitting coils 221 have the same winding direction but different numbers of winding turns, while two adjacent receiving coils 231 have different winding directions and different numbers of winding turns; or, two adjacent transmitting coils 221 have different winding directions and different numbers of winding turns, while two adjacent receiving coils 231 have different winding directions and the same number of winding turns; or, two adjacent transmitting coils 221 have different winding directions and different numbers of winding turns, while two adjacent receiving coils 231 have different winding directions and different numbers of winding turns.

[0070] By setting different combinations of winding directions and numbers of turns for adjacent transmitting coils 221 and receiving coils 231, the characteristics of the transmitting and receiving magnetic fields can be flexibly adjusted. For example, when adjacent transmitting coils 221 have the same winding direction, the alternating magnetic fields generated by each transmitting coil 221 have the same direction. This allows the magnetic fields in the transmitting assembly 220 to overlap, thereby increasing the magnetic field strength and effectively exciting eddy currents, thereby improving the metal detector 200's detection sensitivity for metal objects.

[0071] When the winding directions of adjacent transmitting coils 221 are different or opposite, the electromagnetic coupling between adjacent transmitting coils 221 can be reduced, the mutual interference between the coils can be reduced, and the uniformity of the magnetic field distribution can be improved;

[0072] When adjacent transmitting coils 221 have different numbers of turns, the outer coils can have relatively fewer turns, while the inner coils can have relatively more turns. This ensures that a sufficiently strong external detection magnetic field is generated while also generating a magnetic field of appropriate strength in the inner region. It is important to note that when setting the number of turns, the effect of different numbers of turns on the total magnetic field distribution and energy loss must be considered, and a reasonable design must be made based on the power and detection range requirements of the detector.

[0073] When the winding directions of adjacent receiving coils 231 are different or opposite, the magnetic field induction directions in the overlapping area of the receiving component 230 are opposite, and the eddy current magnetic field changes generated by the metal object in the overlapping area will induce electromotive forces in opposite directions in the two receiving coils 231. This setting can reduce the influence of background noise by comparing the signal difference between the two receiving coils 231, enhance the ability to identify real metal signals, and thus improve the anti-interference performance of the detector. If the winding directions are the same, a large mutual induction magnetic field will be generated between the adjacent receiving coils 231, which will interfere with the metal detector 200's detection of the weak magnetic field generated by the target metal, resulting in inaccurate signals.

[0074] When adjacent receiving coils 231 have the same number of turns, their response characteristics to magnetic field changes in the overlapping region are essentially the same, ensuring uniform detection performance of the receiving coils 231 in the overlapping region and facilitating signal processing and analysis. For example, in a signal processing circuit, the same number of turns means that under the same magnetic field changes, the induced electromotive force generated by the two receiving coils 231 is essentially the same, facilitating signal comparison and integration.

[0075] When adjacent receiving coils 231 have different numbers of turns, their sensitivity to magnetic field changes will vary within the overlapping region. Coils with more turns are more sensitive to magnetic field changes and induce stronger electromotive forces. For example, by properly selecting different combinations of turns, optimal detection of metal objects of different sizes or distances can be achieved. For example, a coil with fewer turns can be used to detect metal objects that are farther away or larger, while a coil with more turns can be used to detect metal objects that are closer or smaller.

[0076] By rationally adjusting the winding direction, number of turns, etc. of the transmitting coil 221 and the receiving coil 231, the present application can, on the one hand, enable the transmitting component 220 to achieve a balance between the magnetic field coverage range and penetration capability; on the other hand, it can also enable the receiving component 230 to achieve a balance between the response sensitivity and accuracy of the induced magnetic field, thereby improving the metal detector 200's detection adaptability and resolution capability for metal foreign objects of various shapes, sizes and materials.

[0077] In some embodiments, a first shielding layer (not shown) is provided between two adjacent transmitting coils 221, and a second shielding layer (not shown) is provided between two adjacent receiving coils 231. Optionally, both the first shielding layer and the second shielding layer may be permalloy or a conductive coating.

[0078] The provision of the first and second shielding layers effectively reduces electromagnetic interference between the coils. Furthermore, the presence of the shielding layers prevents mutual induction between the transmitting coils 221 and signal crosstalk between the receiving coils 231, ensuring that the alternating magnetic field generated by each transmitting coil 221 accurately impacts the metallic foreign matter in the material and enabling the receiving coils 231 to independently and clearly sense the induced magnetic field signal generated by the metallic foreign matter. This improves the detector's detection accuracy and stability, avoiding misjudgments or missed detections due to electromagnetic interference. Furthermore, the provision of the shielding layers reduces the detector's background noise, enabling the system to detect even weaker magnetic field variations, making it particularly suitable for the high-precision medical and electronics industries.

[0079] In some embodiments, reference Figure 5 and Figure 6 As shown, the metal detection system further includes a cutting device 300 disposed on the conveyor frame 110. The cutting device 300 includes an X-axis translation assembly 310, a Y-axis translation assembly 320, and a Z-axis translation assembly 330. The X-axis translation assembly 310 is disposed on both sides of the conveyor frame 110 along the length of the conveyor belt 120. The Y-axis translation assembly 320 cooperates with the X-axis translation assembly 310 along the width of the conveyor belt 120 and is located above the conveyor frame 110. The Z-axis translation assembly 330 cooperates with the Y-axis translation assembly 320 in the vertical direction and has a rotating cutter 331 capable of contacting the material.

[0080] By introducing the cutting device 300, the system can quickly and accurately cut and remove materials containing metal foreign matter based on the metal foreign matter location information detected by the detector. The coordinated use of the X-axis, Y-axis, and Z-axis translation components 330 enables the flexible movement of the rotary cutter 331 in three-dimensional space, enabling it to adapt to materials of different sizes and shapes, as well as metal foreign matter in different locations. The application of this automated cutting device 300 not only improves production efficiency and reduces the cost and labor intensity of manual intervention, but also effectively avoids the risk of misjudgment and secondary contamination that may result from manual operation, ensuring the quality of materials and the safety of production.

[0081] Optionally, the X-axis, Y-axis and Z-axis translation assemblies 330 can be linear modules, guide rail-slider structures, or lead screw-nut structures. This application does not limit the specific structure of the X-axis, Y-axis and Z-axis translation assemblies 330.

[0082] Furthermore, the angle between the rotary cutter 331 and the conveyor belt 120 is less than 90°. This arrangement disperses the cutting force exerted by the rotary cutter 331 on the material, making the cutting action softer and more continuous. This avoids problems such as edge chipping, breakage, or uneven cutting caused by excessive localized force on the material caused by vertical cutting, thereby improving cutting quality, making the edges of the cut material neater and smoother, and enhancing the stability of the cutting process.

[0083] In some embodiments, reference Figure 6-Figure 8 As shown, the X-axis translation assembly 310 includes horizontal guide rails 311 respectively arranged on both sides of the conveyor frame 110 and first sliders 312 respectively matched with the horizontal guide rails 311, and a first driving unit (not shown in the figure) for driving the first slider 312 to move along the horizontal guide rails 311; the Y-axis translation assembly 320 includes a transverse guide rail 321 connected to the first slider 312 and a second slider 322 matched with the transverse guide rail 321, and a second driving unit 323 for driving the second slider 322 to move along the transverse guide rail 321; the Z-axis translation assembly 330 includes a fixed base 332 connected to the second slider 322, a vertical guide rail 333 arranged on the fixed base 332, a third slider 334 matched with the vertical guide rail 333, a cutting base 335 connected to the third slider 334 and used to fix the rotary cutter 331, and a third driving unit 336 for driving the third slider 334 to move along the vertical guide rail 333.

[0084] The rational configuration of the guide rails, sliders, and drive units within the aforementioned components ensures smooth and accurate movement of the cutting device 300, ensuring that the rotary cutter 331 cuts the material along the predetermined path and position. This structural design also helps extend the lifespan and reliability of the cutting device 300, reducing maintenance costs.

[0085] In some embodiments, reference Figure 9 As shown, the metal detection system also includes a winding device 400 respectively arranged on both sides of the conveying device 100, and the winding device 400 includes a mounting frame 410 and a pressure roller 420 arranged on the mounting frame 410, and a fourth drive unit (not marked in the figure) connected to the pressure roller 420, and under the drive of the fourth drive unit, the pressure roller 420 can rotate relative to the mounting frame 410 to reel in the material on the conveying device 100.

[0086] The reeling device 400 effectively reels the material on the conveyor 100, facilitating the sorting and subsequent processing of the inspected material. Driven by the fourth drive unit, the pressure roller 420 evenly reels the material onto the mounting frame 410, preventing looseness, wrinkles, or damage during the reeling process. The use of the reeling device 400 not only improves material collection efficiency but also provides strong support for the automation and continuity of the production process, facilitating centralized material management and optimal resource utilization.

[0087] In other embodiments, the metal detection system may further include an image acquisition device (not shown in the figure), and a control device (not labeled in the figure) electrically connected to the image acquisition device, the cutting device 300, the conveying device 100, and the metal detector 200. In response to image information captured by the image acquisition device, the control device may control the rotary cutter 331 in the cutting device 300 to cut the material on the conveyor belt 120 based on the received image information and the magnetic field signal sent by the metal detector 200.

[0088] For ease of understanding, the above control process is described below using a specific example:

[0089] When the metal detector determines the presence of metal foreign matter through signal changes in an independent detection zone or a composite detection zone, the system immediately triggers the following actions:

[0090] Calculate the horizontal and vertical positions of the metal foreign body in the material based on the electromagnetic signal and record the preliminary coordinates (X1, Y1) of the metal foreign body;

[0091] The control device then controls the conveyor belt to decelerate to a low speed mode (e.g., 0.1 m / s) to reduce the impact of motion blur on image acquisition;

[0092] The image acquisition device (such as an industrial camera) installed above the detector housing can be equipped with a ring-shaped LED light source (wavelength 450-650nm) and trigger high-speed continuous shooting (3-5 frames) near the coordinates of the metal foreign body. The viewing angle of the image acquisition device covers the width of the conveyor belt, and the focus and angle are adjusted by the servo pan-tilt platform to ensure a clear image of the target area.

[0093] De-noising, contrast enhancement and perspective correction are performed on the images captured by the image acquisition device to eliminate interference from conveyor belt texture or packaging pattern on the captured images;

[0094] The collected images are analyzed in real time using a preset convolutional neural network model (such as YOLOv5) to identify the outline, reflective properties, and differences between the metal foreign body and the background.

[0095] If there are bright reflective spots, irregular edges or areas with abnormal density in the image, the area will be identified as a candidate area for metal foreign matter;

[0096] The pixel coordinates (u, v) of the metal foreign body in the image are converted to the conveyor belt coordinates (X2, Y2) through the calibration matrix. The formula is:

[0097]

[0098] Among them, k x , k y is the pixel-physical size conversion coefficient, u0, v0 is the image center offset, t delay is the time difference between magnetic field signal detection and image acquisition;

[0099] If the deviation between the preliminary coordinates (X1, Y1) of the metal foreign body and the conveyor belt coordinates (X2, Y2) is less than or equal to 3mm, the metal foreign body is determined to be a credible target and the cutting coordinates (X, Y) = ((X1+X2) / 2, (Y1+Y2) / 2) are generated. If the deviation is greater than 3mm, the conveyor belt is controlled to move in the opposite direction for 0.5m, and the preliminary coordinates of the metal foreign body and the conveyor belt coordinates are recollected for verification.

[0100] According to the cutting coordinates (X, Y), the X / Y axis translation component of the cutting device moves along the length (X axis) and width (Y axis) of the conveyor belt to the top of the target. The motion trajectory is optimized by the B-spline curve interpolation algorithm to avoid collision with materials or equipment.

[0101] The contact force between the rotary cutter and the material is monitored in real time by a pressure sensor installed on the Z-axis translation assembly to ensure that the cutting depth is adaptive to the thickness of the material (e.g., cutting depth = material thickness + 2mm);

[0102] When the rotary cutter is cutting, the resection area can be a dynamic-size square centered on the metal foreign object, and the image acquisition device continuously monitors the resection area. If residual metal fragments are detected, a secondary cutting action is triggered. The size of the dynamic-size square is determined according to the following standards: when the size of the metal foreign object is less than or equal to 1mm, the size of the dynamic-size square can be 30×30mm; when the size of the metal foreign object is greater than 1mm, the size of the dynamic-size square can be 50×50mm.

[0103] In addition, the present invention also provides a metal detection method with a partition detection function, which is applied to the above metal detection system and includes the following steps:

[0104] S100. Under the conveyance of the conveying device, the material can move along the length direction of the conveyor belt.

[0105] S200: In response to the connection with the external high-frequency alternating current, the metal detector starts to work, and the transmitting component and the receiving component in the detector respectively form a ring-shaped transmitting area, an independent detection area, and a composite detection area.

[0106] S300. When the material is transported to the annular launch area by the conveyor belt, the alternating magnetic field generated by the launch component acts on the metal foreign matter at different positions in the material to form different eddy currents.

[0107] S400. Different eddy currents form different induced magnetic fields, and the different induced magnetic fields can act on the independent detection area and / or the composite detection area in the receiving component respectively, and enable the receiving component to generate magnetic field signals corresponding to the independent detection area and / or the composite detection area.

[0108] S500: Determine the specific location of the metal foreign matter in the material based on the received magnetic field signal.

[0109] The method provided by the present invention enables rapid and precise detection and location of metallic foreign matter in materials. By conveying the material through a circular emission zone, an independent detection zone, and a composite detection zone, the material is transported by a conveyor. By utilizing the interaction between the alternating magnetic field generated by the emission component and the metallic foreign matter, and the reception and analysis of the induced magnetic field signal by the receiving component, the specific location of the metallic foreign matter in the material can be accurately determined. This method effectively improves the efficiency and accuracy of metal detection, provides reliable technical support for material quality control and safety assurance in industrial production, and helps reduce production costs, improve product quality, and increase production efficiency.

[0110] In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the present invention may be practiced without these specific details. Similarly, in order to streamline the present invention and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, various features of embodiments of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. The claims that follow the detailed description are hereby expressly incorporated into that detailed description, with each claim itself serving as a separate embodiment of the present invention.

[0111] It should be noted that the above embodiments illustrate rather than limit the invention, and that alternative embodiments may be devised by a person skilled in the art without departing from the scope of the appended claims. In the claims, any reference signs placed between brackets should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present invention may be implemented by means of hardware comprising several different elements and by means of appropriately programmed computers. In a unit claim enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third etc. does not indicate any order. These words may be interpreted as names. The steps in the above embodiments should not be understood as limiting the order of execution unless otherwise specified.

Claims

1. A metal detection system with partition detection function, characterized in that: include: A conveying device comprising a conveying frame and a conveyor belt arranged on the conveying frame; A metal detector comprising a housing located on the conveyor frame and a detector disposed within the housing, the detector comprising a transmitting assembly and a receiving assembly, wherein the transmitting assembly forms an annular transmitting area along the width direction of the conveyor belt, and the receiving assembly forms an independent detection area and a composite detection area corresponding to the annular transmitting area; Wherein, in response to the movement of the conveyor belt, the detector is used to determine the position of the metal foreign matter passing through the annular emission area, the independent detection area and the composite detection area in the material on the conveyor belt.

2. The metal detection system according to claim 1, characterized in that The transmitting component has multiple transmitting coils nested in each other, the receiving component has multiple receiving coils partially overlapping each other, and the annular transmitting area is the area formed by the alternating magnetic field generated by the multiple transmitting coils, the independent detection area is the area formed by the non-overlapping parts between the multiple receiving coils for inducing changes in the alternating magnetic field, and the composite detection area is the area formed by the overlapping parts between the multiple receiving coils for inducing changes in the alternating magnetic field.

3. The metal detection system according to claim 2, characterized in that The plurality of transmitting coils are configured to be located in a first plane parallel to the horizontal direction, and the plurality of receiving coils are configured to be located in a second plane parallel to the horizontal direction; The first plane and the second plane are the same plane, or the first plane and the second plane are different parallel planes.

4. The metal detection system according to claim 3, characterized in that The area of the overlapping portion between two adjacent receiving coils is between 1 / 5 and 4 / 5.

5. The metal detection system according to claim 2, characterized in that: The winding directions of the two adjacent transmitting coils are the same but the number of winding turns is different, and the winding directions of the two adjacent receiving coils are different but the number of winding turns is the same; or, The winding directions of the two adjacent transmitting coils are the same but the number of winding turns is different, and the winding directions of the two adjacent receiving coils are different but the number of winding turns is different; or, The winding directions and the number of winding turns of the two adjacent transmitting coils are different, and the winding directions and the number of winding turns of the two adjacent receiving coils are different, and the number of winding turns of the two adjacent receiving coils are the same; or, The winding directions and the number of winding turns of the two adjacent transmitting coils are different, and the winding directions and the number of winding turns of the two adjacent receiving coils are different.

6. The metal detection system according to claim 2, characterized in that: A first shielding layer is provided between two adjacent transmitting coils, and a second shielding layer is provided between two adjacent receiving coils.

7. The metal detection system according to claim 1, characterized in that The metal detection system further includes a cutting device provided on the conveyor frame, the cutting device including: X-axis translation components are arranged on both sides of the conveyor frame along the length direction of the conveyor belt; a Y-axis translation assembly, cooperating with the X-axis translation assembly along the width direction of the conveyor belt and located above the conveyor frame; The Z-axis translation assembly cooperates with the Y-axis translation assembly in a vertical direction and has a rotary cutter capable of contacting the material.

8. The metal detection system according to claim 7, characterized in that: The X-axis translation assembly includes horizontal guide rails respectively provided on both sides of the conveyor frame, first sliders respectively matched with the horizontal guide rails, and a first driving unit for driving the first sliders to move along the horizontal guide rails; The Y-axis translation assembly includes a transverse guide rail connected to the first slider, a second slider matched with the transverse guide rail, and a second driving unit for driving the second slider to move along the transverse guide rail; The Z-axis translation assembly includes a fixed seat connected to the second slider, a vertical guide rail arranged on the fixed seat, a third slider cooperating with the vertical guide rail, a cutting seat connected to the third slider and used to fix the rotary cutter, and a third driving unit for driving the third slider to move along the vertical guide rail.

9. The metal detection system according to claim 1, characterized in that: The metal detection system further includes a reeling device respectively provided on both sides of the conveying device, and the reeling device includes: Mounting rack; A pressure roller provided on the mounting frame; and a fourth driving unit connected to the pressure roller, and under the drive of the fourth driving unit, the pressure roller can rotate relative to the mounting frame to reel in the material on the conveying device.

10. A metal detection method with a partition detection function, characterized in that: The method is applied to the metal detection system according to any one of claims 1 to 9, comprising the following steps: Under the conveying device, the material can move along the length of the conveyor belt; In response to the connection with the external high-frequency alternating current, the metal detector starts to work, and the transmitting component and the receiving component in the detector respectively form a ring-shaped transmitting area, an independent detection area and a composite detection area; When the material is transported to the annular launch area by the conveyor belt, the alternating magnetic field generated by the launch component acts on the metal foreign matter at different positions in the material to form different eddy currents; Different eddy currents form different induced magnetic fields, and the different induced magnetic fields can act on the independent detection area and / or the composite detection area in the receiving component respectively, and cause the receiving component to generate magnetic field signals corresponding to the independent detection area and / or the composite detection area; According to the received magnetic field signal, the specific location of the metal foreign matter in the material is determined.

Images