Coil structure, walk-through detector, and coil control method

Abstract

A coil structure, a walk-through detector, and a coil control method, relating to the technical field of detector design. The coil structure comprises a transmitting coil group, and the transmitting coil group comprises a first transmitting coil group and a second transmitting coil group. The first transmitting coil group and the second transmitting coil group are arranged in an overlapping manner. The positions of blind zones of magnetic induction lines in the Z-axis direction of the first transmitting coil group are different from the positions of blind zones of magnetic induction lines in the Z-axis direction of the second transmitting coil group, and at least one blind zone of a magnetic induction line in the Z-axis direction is opposite to an overlapping area of the first transmitting coil group and the second transmitting coil group.

Description

Coil structure, pass-through detector, and coil control method

[0001] This application claims priority to the Chinese patent applications filed with the Patent Office of China on December 15, 2023, with application number 2023234312152 and application name “A coil structure, a pass-through detector, and a method for controlling a coil” and filed with the Patent Office of China on April 26, 2024, with application number 202410511545.2 and application name “A coil structure, a pass-through detector, and a method for controlling a coil”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of detector design, and in particular to a coil structure, a pass-through detector, and a coil control method. Background Art

[0003] In public places such as airports and train stations, detectors are usually used to detect metals or contraband, such as setting up walk-through detectors to detect objects.

[0004] Traditional walk-through detectors have coils installed in the door panels on both sides. The magnetic lines of force inside the detector are distributed primarily horizontally (in the X direction) from one door panel to the other, but there are significant blind spots in the Y and Z directions. If the person being measured is carrying a metal panel or mobile phone, and they pass through the walk-through detector with their largest cross-section parallel to the horizontal magnetic lines of force, the metal panel or phone will have a very small cross-section on the side that passes through the horizontal magnetic lines of force. Consequently, fewer magnetic lines of force will pass through, resulting in a smaller eddy current effect and a weaker eddy current signal. This can cause the detector to miss detections, significantly reducing the reliability of the detection results.

[0005] It can be seen that how to improve the reliability of detector detection results is a technical problem that people in this field urgently need to solve. Summary of the Invention

[0006] Based on this, it is necessary to provide a coil structure, a pass-through detector and a coil control method.

[0007] A coil structure includes a transmitting coil assembly, the transmitting coil assembly including a first transmitting coil assembly and a second transmitting coil assembly. The first transmitting coil assembly and the second transmitting coil assembly are arranged overlappingly. The positions of the blind areas of the first transmitting coil assembly and the second transmitting coil assembly in the Z-axis direction are different, and at least one of the blind areas of the Z-axis direction magnetic flux lines is opposite to the intersection of the first and second transmitting coil assemblies.

[0008] A walk-through detector includes a door panel structure comprising a first door panel and a second door panel. It also includes a coil structure, wherein the coil structure includes two sets of transmitting coil assemblies disposed opposite each other, one set of transmitting coil assemblies disposed in the first door panel and the other set of transmitting coil assemblies disposed in the second door panel. The coil structure includes transmitting coil assemblies, each comprising a first transmitting coil assembly and a second transmitting coil assembly. The first transmitting coil assembly and the second transmitting coil assembly are positioned overlapping. The blind area of ​​the first transmitting coil assembly in the Z-axis direction is located differently from the blind area of ​​the second transmitting coil assembly in the Z-axis direction, and at least one blind area of ​​the Z-axis direction magnetic flux lines is opposite the intersection of the first and second transmitting coil assemblies.

[0009] A coil control method is applied to a coil structure, wherein the coil structure includes two transmitting coil groups arranged opposite to each other, the transmitting coil groups including a first transmitting coil group and a second transmitting coil group; the first transmitting coil group and the second transmitting coil group are arranged overlappingly;

[0010] The position of the blind area of ​​the magnetic flux lines of the first transmitting coil group in the Z-axis direction is different from the position of the blind area of ​​the magnetic flux lines of the second transmitting coil group in the Z-axis direction, and at least one of the blind areas of the magnetic flux lines in the Z-axis direction is opposite to the intersection area of ​​the first transmitting coil group and the second transmitting coil group;

[0011] The method comprises:

[0012] Controlling the coil structure to alternately switch between three operating modes;

[0013] The three working modes include:

[0014] Working mode 1: the first transmitting coil group is energized and the second transmitting coil group is not energized, and the currents flowing through the first transmitting coil groups arranged opposite to each other have the same direction;

[0015] Working mode 2: the first transmitting coil group is energized, the second transmitting coil group is not energized, and the directions of the currents flowing through the first transmitting coil groups arranged opposite to each other are opposite;

[0016] Working mode three: the first transmitting coil group is controlled to be de-energized and the second transmitting coil group is energized, and the directions of the currents flowing through the second transmitting coil groups arranged opposite to each other are opposite.

[0017] The details of one or more embodiments of the present application are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, without paying any creative work, they can also obtain drawings of other embodiments based on these drawings.

[0019] FIG1 is a schematic diagram of a pass-through detector provided in an embodiment of the present application;

[0020] FIG2 is an exploded view of a coil structure provided in an embodiment of the present application;

[0021] FIG3 is a schematic diagram of the first transmitting coil group in the coil structure shown in FIG2 forming a superposition field;

[0022] FIG4 is a schematic diagram of a repulsive field formed by the first transmitting coil group in the coil structure shown in FIG2 ;

[0023] FIG5 is a schematic diagram of a repulsive field formed by the second transmitting coil group in the coil structure shown in FIG2 ;

[0024] FIG6 is a schematic diagram of the magnetic flux lines in the X-axis direction of the coil structure shown in FIG2 in the working mode;

[0025] FIG7 is a schematic diagram of magnetic flux lines in the Y-axis direction of the coil structure shown in FIG2 in working mode 2;

[0026] FIG8 is a schematic diagram of magnetic flux lines in the Z-axis direction of the coil structure shown in FIG2 in working mode 2;

[0027] FIG9 is a schematic diagram of magnetic flux lines in the Z-axis direction of the coil structure shown in FIG2 in working mode three;

[0028] FIG10 is a schematic diagram of a coil structure provided by another embodiment.

[0029] The reference numerals are as follows: 10 is a first door panel, 20 is a second door panel, 30 is a top panel, 1 is a transmitting coil group, 11 is a first transmitting coil group, 12 is a second transmitting coil group, 111, 112, 113, and 114 are respectively first sub-coils on the first transmitting coil group 11, 121 is a sub-coil group on the second transmitting coil group 12, and 1211 and 1212 are respectively second sub-coils in the sub-coil groups. DETAILED DESCRIPTION

[0030] To facilitate understanding of the present application, a more comprehensive description of the present application will be provided below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present application. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present application.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit this application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0032] The above description includes examples of one or more embodiments. Of course, it is not possible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it will be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, to the extent that the term "comprising" is used in the specification or claims, the term is intended to be encompassed in a manner similar to the term "including", as explained by the use of "including" as a transitional word in the claims. In addition, any use of the term "or" in the specification of the claims is intended to mean a "non-exclusive or".

[0033] The embodiments of the present application provide a coil structure, a pass-through detector, and a coil control method to solve the technical problem of low reliability of detector detection results.

[0034] It should be noted that the coil structure provided in the embodiment of the present application is used in a device for detecting a target object, wherein the target object is, for example, metal. The coil structure can be applied to a pass-through detector (such as a security gate) and is suitable for a variety of places, such as airports, stations, etc.

[0035] In order to help those skilled in the art better understand the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific implementations. The present invention provides a coil structure including a transmitting coil assembly 1 .

[0036] The transmitting coil assembly 1 includes a first transmitting coil assembly 11 and a second transmitting coil assembly 12. The first transmitting coil assembly 11 and the second transmitting coil assembly 12 are arranged overlapping. The blind area of ​​the magnetic flux lines in the Z-axis direction of the first transmitting coil assembly 11 is located at a different position than the blind area of ​​the magnetic flux lines in the Z-axis direction of the second transmitting coil assembly 12, and at least one blind area is opposite the intersection area of ​​the first transmitting coil assembly 11 and the second transmitting coil assembly 12.

[0037] In conventional coil structures used for detection, the magnetic flux lines inside the detector are distributed between the two door panels, essentially along the horizontal direction, i.e., the X-axis direction. However, there are numerous blind spots in the Y-axis and Z-axis directions, which can cause the detector to miss detections. Therefore, in the embodiment of the present application, the transmitting coil assembly 1 includes a first transmitting coil assembly 11 and a second transmitting coil assembly 12. To facilitate the description of the coil structure, the directions of the X-axis, Y-axis, and Z-axis are first described using FIG1 as an example. FIG1 is a schematic diagram of a pass-through detector provided in an embodiment of the present application. As shown in FIG1 , the pass-through detector includes a first door panel 10, a second door panel 20, and a top panel 30. A detection channel is formed between the first door panel 10 and the second door panel 20. A transmitting coil assembly 1 is provided on each of the first door panel 10 and the second door panel 20. The Y-axis is parallel to the bottom edge m of the first door panel 10 (i.e., the direction in which a pedestrian walks through the pass-through detector), the X-axis is perpendicular to the bottom edge m of the first door panel 10, and the Z-axis is parallel to the side edge n of the first door panel 10. FIG1 is only a reference diagram of the directions of the X-axis, the Y-axis, and the Z-axis. In practice, the directions of the X-axis, the Y-axis, and the Z-axis may be changed according to actual conditions.

[0038] The first transmitting coil assembly 11 and the second transmitting coil assembly 12 are placed overlapping. The structure of the first transmitting coil assembly 11, the structure of the second transmitting coil assembly 12, the position of the first transmitting coil assembly 11, the position of the second transmitting coil assembly 12, the direction of the current in the first transmitting coil assembly 11, and the direction of the current in the second transmitting coil assembly 12 are not limited and are determined according to actual conditions.

[0039] Specifically, overlapping placement includes completely overlapping the first transmitting coil assembly 11 and the second transmitting coil assembly 12 (e.g., the entire second transmitting coil assembly 12 is stacked on the first transmitting coil assembly 11) or partially overlapping (e.g., only a portion of the live wires of the second transmitting coil assembly 12 are stacked on the first transmitting coil assembly 11). The intersection region is the area where the first transmitting coil assembly 11 and the second transmitting coil assembly 12 overlap. For example, in Figures 1 and 2, the entire second transmitting coil assembly 12 is stacked on the first transmitting coil assembly 11. The intersection region is defined as the area between live wires r and q in the first transmitting coil assembly 11 and the area between live wires s and t in the second transmitting coil assembly 12.

[0040] Of course, in other embodiments, if the second transmitting coil assembly 12 moves upward or downward, then the first transmitting coil assembly 11 and the second transmitting coil assembly 12 partially overlap, and the intersection area is only the area where the first transmitting coil assembly 11 and the second transmitting coil assembly 12 overlap.

[0041] The term "blind zone" for magnetic flux lines in the Z-axis direction refers to a zone where there are no magnetic flux lines in the Z-axis direction. For ease of description, this "blind zone for magnetic flux lines in the Z-axis direction" will be referred to as the Z-axis blind zone. The Z-axis blind zone is located within the detection area, for example, within the detection channel of a pass-through detector. Therefore, if an object passes through the detection channel and happens to be within the Z-axis blind zone, it cannot be detected. In this embodiment, the Z-axis blind zones of the first transmitting coil assembly 11 and the second transmitting coil assembly 12 are located differently, meaning that the location of at least one Z-axis blind zone of one of the first transmitting coil assembly 11 and the second transmitting coil assembly 12 is different from the location of all Z-axis blind zones of the other. The different locations of the two Z-axis blind zones include either the two Z-axis blind zones not overlapping at all or the two Z-axis blind zones partially overlapping. As shown in Figures 2, 4, and 6, the Z-axis blind zone A corresponding to the first transmitting coil assembly 11 and the Z-axis blind zone B on the second transmitting coil assembly 12 do not overlap at all. Similarly, the Z-axis blind zone A and the Z-axis blind zone C do not overlap at all. Alternatively, if the first transmitting coil assembly 11 has a Z-axis blind zone covering a height of [1m, 1.3m], and the Z-axis blind zone closest to the Z-axis blind zone of the second transmitting coil assembly 12 covers a height of [1m, 1.1m], i.e., the heights of the two Z-axis blind zones intersect but are not identical, this situation also falls within the scope of protection of this embodiment. Of course, if none of the Z-axis blind zones of the second transmitting coil assembly 12 have a height within the range of [1m, 1.3m], it also falls within the scope of protection of this embodiment. Furthermore, the positions referred to in this embodiment primarily refer to the Z-axis positions. In other words, two Z-axis blind zones are considered to be different as long as their Z-axis positions differ.

[0042] It should be understood that the "blind zone" referred to in this embodiment refers to a spatial region. As shown in Figure 4, taking the Z-axis blind zone A as an example, when the first transmitting coil assembly 11 on the first door panel 10 and the first transmitting coil assembly 11 on the second door panel 20 are operating, a Z-axis blind zone A is formed between the live wires a and b of the first transmitting coil assembly 11 on the first door panel 10, extending along the X-axis to the first transmitting coil assembly 11 on the second door panel 20.

[0043] Similarly, as shown in FIG5 , the Z-axis blind zone B in this embodiment is defined as the spatial region between the live wires c and d on one door panel, extending along the X-axis to the second transmitting coil assembly 12 on the other door panel when the second transmitting coil assembly 12 on both door panels is in operation. The Z-axis blind zone C is defined as the spatial region between the live wires e and f on one door panel, extending along the X-axis to the second transmitting coil assembly 12 on the other door panel when the second transmitting coil assembly 12 on both door panels is in operation.

[0044] In this embodiment, in addition to the different locations of the Z-axis blind zones of the first and second transmitting coil assemblies 11, 12, at least one Z-axis blind zone is defined to be opposite the intersection region between the first and second transmitting coil assemblies 11, 12. In other words, the Z-axis height of at least one Z-axis blind zone intersects the Z-axis height of the intersection region. It should be noted that the intersection region here is not limited to the entire intersection region between the first and second transmitting coil assemblies 11, 12; a partial intersection region is also acceptable. That is, as long as the first and second transmitting coil assemblies 11, 12 overlap within the height range of the Z-axis blind zone, it suffices. If the first transmitting coil assembly 11 has a Z-axis blind zone opposite the intersection region, then this Z-axis blind zone can at least be opposite the second transmitting coil assembly 12. If the second transmitting coil assembly 12 does not have a Z-axis blind zone at this location, the second transmitting coil assembly 12 can be used to overcome the Z-axis blind zone of the first transmitting coil assembly 11 at this location.

[0045] Specifically, for example, the Z-axis blind zone B of the second transmitting coil assembly 12 is located at the position shown in FIG. 5 . In conjunction with FIG. 1 and FIG. 2 , since the Z-axis blind zone B is opposite the intersection of the first transmitting coil assembly 11 and the second transmitting coil assembly 12, specifically the area between the energized lines 1 and k in the first transmitting coil assembly 11, if the energized lines 1 and k are oriented in the same direction, these two energized lines will not create a Z-axis blind zone. Therefore, by energizing the first transmitting coil assembly 11 and the second transmitting coil assembly 12 sequentially, the first transmitting coil assembly 11 can compensate for the Z-axis blind zone B of the second transmitting coil assembly 12. In other words, if a target is within the Z-axis blind zone B, although the second transmitting coil assembly 12 does not transmit Z-axis magnetic flux lines to the target, the first transmitting coil assembly 11 can transmit magnetic flux lines to the target.

[0046] To help those skilled in the art better understand the coil structure in the embodiments of the present application, the following describes the scheme in the embodiments of the present application using a specific coil structure. FIG2 is an exploded view of a transmitting coil structure provided in an embodiment of the present application. As shown in FIG2 , the transmitting coil assembly 1 includes a first transmitting coil assembly 11 and a second transmitting coil assembly 12. The first transmitting coil assembly 11 and the second transmitting coil assembly 12 both include first current conducting wires along the Y-axis direction (such as current conducting wires a and b in the first transmitting coil assembly 11, and current conducting wires c, d, e, and f in the second transmitting coil assembly 12 in FIG2 ).

[0047] To improve the reliability of detection results obtained when using the coil structure, the Z-axis blind zone of the first transmitting coil assembly 11 is positioned differently from the Z-axis blind zone of the second transmitting coil assembly 12 in the embodiment of the present application. It should be noted that in this embodiment, the Z-axis blind zones of the first transmitting coil assembly 11 and the second transmitting coil assembly 12 are generated by two adjacent current-carrying wires extending along the Y-axis and with opposite current directions.

[0048] With reference to Figures 2, 4, and 5, assume that two adjacent current lines a and b in the first transmitting coil assembly 11, extending along the Y-axis and with opposite currents flowing in opposite directions, form a Z-axis blind zone A in the Z-axis direction; two adjacent current lines c and d in the second transmitting coil assembly 12, extending along the Y-axis and with opposite currents flowing in opposite directions, form a Z-axis blind zone B in the Z-axis direction; and two adjacent current lines e and f, with opposite currents flowing in opposite directions, form another Z-axis blind zone C in the Z-axis direction. Z-axis blind zone A is located in the middle region of the detection channel, while Z-axis blind zone B and Z-axis blind zone C are located in the upper and lower regions of the detection channel, respectively. That is, the location of Z-axis blind zone A is different from that of Z-axis blind zone B and Z-axis blind zone C. Therefore, the second transmitting coil assembly 12 can detect the middle region that the first transmitting coil assembly 11 cannot detect. The first transmitting coil group 11 can detect the upper and lower areas that the second transmitting coil group 12 cannot detect. Through the above configuration, the first transmitting coil group 11 and the second transmitting coil group 12 can compensate for each other's Z-axis blind areas.

[0049] In practice, although the Z-axis blind zones of the first transmitting coil assembly 11 and the second transmitting coil assembly 12 are positioned at different locations, to ensure that the Z-axis blind zones can be compensated for by each other as much as possible, this embodiment provides at least one blind zone opposite the intersection of the first transmitting coil assembly 11 and the second transmitting coil assembly 12. For example, the Z-axis blind zone A of the first transmitting coil assembly 11 is opposite the area between the live wires i and j in the second transmitting coil assembly 12. Since the area between the live wires i and j and the area between the live wires i and j is located in the intersection area, and the current directions of the live wires i and j are the same, normal detection is possible. Therefore, with the cooperation of the first transmitting coil assembly 11 and the second transmitting coil assembly 12, if a target passes through the channel area corresponding to the area between the live wires a and b (also corresponding to the area between the live wires i and j), it can be normally detected.

[0050] In the coil structure provided in this embodiment, the coil arrangement in which the first transmitting coil assembly 11 and the second transmitting coil assembly 12 are overlapped is arranged. Since the position of the Z-axis blind zone of the first transmitting coil assembly 11 is different from the position of the Z-axis blind zone of the second transmitting coil assembly 12, and at least one blind zone is opposite the intersection area of ​​the first transmitting coil assembly 11 and the second transmitting coil assembly 12, the first transmitting coil assembly 11 and the second transmitting coil assembly 12 can compensate for each other's Z-axis blind zone, thereby increasing the probability of detecting the target in various postures, improving the sensitivity and reliability of monitoring, and facilitating practical production applications.

[0051] In the above embodiment, the Z-axis blind zone of the first transmitting coil assembly 11 does not overlap with the Z-axis blind zone of the second transmitting coil assembly 12. However, in other embodiments (not shown), the Z-axis blind zone of the first transmitting coil assembly 11 and the Z-axis blind zone of the second transmitting coil assembly 12 may partially overlap.

[0052] To maximize the compensation of the blind spot in the Z-axis direction, in some embodiments, the projection of the region between two adjacent first current-carrying lines with opposite current directions in the first transmitting coil group 11 on the plane defined by the Y-axis and the Z-axis does not intersect or partially intersects with the projection of the region between two adjacent first current-carrying lines with opposite current directions in the second transmitting coil group 12 on the plane defined by the Y-axis and the Z-axis.

[0053] Because two adjacent first conducting lines with opposite current directions will generate a Z-axis blind zone, this embodiment is equivalent to limiting the Z-axis blind zone of the first transmitting coil assembly 11 to non-intersecting or partially intersecting the Z-axis blind zone of the second transmitting coil assembly 12. For example, as shown in Figures 2 and 4, the projection of the area between two adjacent first conducting lines with opposite current directions (conducting lines a and b) in the first transmitting coil assembly 11 on the plane formed by the Y and Z axes does not intersect with the projection of the area between two adjacent first conducting lines with opposite current directions (the area between conducting lines c and d, or the area between conducting lines e and f) in the second transmitting coil assembly 12 on the plane formed by the Y and Z axes. That is, Z-axis blind zone A does not intersect with Z-axis blind zone B, and Z-axis blind zone A does not intersect with Z-axis blind zone C. In the coil structure provided in this embodiment, by setting the Z-axis blind zone of the first transmitting coil assembly 11 and the Z-axis blind zone of the second transmitting coil assembly 12 to non-intersecting, the coil structure is guaranteed to have no blind zone on the Z axis, thereby improving the accuracy of coil structure detection.

[0054] In other embodiments, the Z-axis blind areas of the first transmitting coil assembly 11 and the second transmitting coil assembly 12 may also partially intersect. If they do, this means their Z-axis blind areas partially intersect and partially disjoint. For this disjoint portion, the first transmitting coil assembly 11 and the second transmitting coil assembly 12 can similarly compensate for each other's Z-axis blind areas (the principle is similar to the aforementioned non-intersection scenario and will not be further elaborated here), thus similarly reducing the extent of the Z-axis blind area.

[0055] The coil structure shown in FIG. 2 is further described below. In the coil structure shown in FIG. 2 , both the first transmitting coil assembly 11 and the second transmitting coil assembly 12 further include a second conducting line along the Z-axis. Specifically, the second conducting line along the Z-axis in the first transmitting coil assembly 11 is exemplified by conducting line g, and the second conducting line along the Z-axis in the second transmitting coil assembly 12 is exemplified by conducting line h.

[0056] The first transmitting coil assembly 11 includes multiple first sub-coils. The projections of each first sub-coil on the plane defined by the Y-axis and the Z-axis are nested one after another, and the current flowing through them is in the same direction. There is no limit on the number of first sub-coils in the first transmitting coil assembly 11. All first sub-coils can be located in the same plane or in different planes. A first sub-coil includes a first current conducting wire and a second current conducting wire, and the first current conducting wire and the second current conducting wire are connected. For example, a first sub-coil is rectangular and enclosed by two first current conducting wires and two second current conducting wires. Figure 2 shows four first sub-coils in the first transmitting coil assembly 11: first sub-coils 111, 112, 113, and 114, nested in sequence. The direction of the current flowing through the first sub-coils is not limited; it suffices to ensure that the current flows in the same direction across all first sub-coils in the first transmitting coil assembly 11. FIG3 is a schematic diagram illustrating the formation of a superposition field by the first transmitting coil assembly 11 in the coil structure shown in FIG2 . As shown in FIG3 , the direction of the current flowing through each first sub-coil in the first transmitting coil assembly 11 on the first door panel 10 is counterclockwise, and the direction of the current flowing through each first sub-coil 11 on the second door panel 20 is counterclockwise. FIG4 is a schematic diagram illustrating the formation of a repulsive field by the first transmitting coil assembly 11 in the coil structure shown in FIG2 . As shown in FIG4 , the direction of the current flowing through each first sub-coil in the first transmitting coil assembly 11 on the first door panel 10 is counterclockwise, and the direction of the current flowing through each first sub-coil 11 on the second door panel 20 is clockwise.

[0057] The second transmitting coil group 12 includes a plurality of sub-coil groups 121 . The sub-coil groups 121 are sequentially arranged along the Z axis, and two adjacent sub-coil groups 121 are spaced apart or overlapped. The directions of the currents in adjacent sub-coil groups 121 are opposite.

[0058] The number of sub-coil assemblies 121 in the second transmitting coil assembly 12 and the specific structure of each sub-coil assembly 121 are not limited and are determined based on actual conditions. Furthermore, the direction of the current flowing through each sub-coil assembly 121 is not limited, as long as the currents flowing through adjacent sub-coil assemblies 121 are in opposite directions.

[0059] As shown in FIG3 , because the first transmitting coil assembly 11 includes multiple first sub-coils nested one after another and with currents flowing in the same direction, in the repulsive field mode, the two first conducting lines, namely, conducting line a and conducting line b, in the innermost first sub-coil (i.e., first sub-coil 114) of the first transmitting coil assembly 11 are located in the center and have currents flowing in opposite directions. Conducting lines a and conducting line b create a Z-axis blind spot A. Simultaneously, as shown in FIG5 , because the second transmitting coil assembly 12 includes multiple sub-coil assemblies 121, with currents flowing in opposite directions between two adjacent sub-coil assemblies 121, if there are two sub-coil assemblies 121, these two sub-coil assemblies 121 can be arranged vertically along the Z-axis. Furthermore, these two sub-coil assemblies 121 have two adjacent first conducting lines, namely, conducting line i and conducting line j, with currents flowing in the same direction and located exactly in the center. This compensates for the Z-axis blind spot of conducting lines a and conducting line b, which are also located in the center of the first transmitting coil assembly 11.

[0060] Furthermore, each sub-coil group 121 includes multiple second sub-coils whose projections on the plane defined by the Y-axis and the Z-axis intersect, and the currents in each second sub-coil have the same direction. All second sub-coils may be located in the same plane or in different planes. The second sub-coils also include a first current conducting wire and a second current conducting wire, which are connected. For example, the second sub-coil is rectangular and enclosed by two first current conducting wires and two second current conducting wires. As shown in Figures 2 and 5, the second transmitting coil group 12 may specifically include two spaced-apart sub-coil groups 121, each of which includes two overlapping second sub-coils 1211 and 1212. Figure 5 is a schematic diagram of the repulsive field formed by the second transmitting coil group in the coil structure shown in Figure 2. As shown in Figure 5, the second transmitting coil group 12 includes two spaced-apart sub-coil groups 121, with the currents in the two sub-coil groups 121 flowing in opposite directions, and the currents in the second sub-coils 1211 and 1212 in each sub-coil group 121 have the same direction.

[0061] In other embodiments not shown, two adjacent sub-coil assemblies 121 may also be arranged in an overlapping manner. For example, in Figures 2 and 5, the upper sub-coil assembly 121 and the lower sub-coil assembly 121 may have an overlapping region. Specifically, the overlapping region of two adjacent sub-coil assemblies 121 may be formed by the second sub-coil 1212 in the upper sub-coil assembly 121 overlapping the second sub-coil 1211 in the lower sub-coil assembly 121. Because the current directions of the conductive lines i and j are the same, the overlapping arrangement of two adjacent sub-coil assemblies 121 can also compensate for the Z-axis blind spot caused by the conductive lines a and b in the first sub-coil assembly 11.

[0062] Specifically, in Figure 5 , the direction of the current in the second sub-coil 1211 and the direction of the current in the second sub-coil 1212 in the sub-coil group 121 on the upper portion of the first door panel 10 are both counterclockwise, and the direction of the current in the second sub-coil 1211 and the direction of the current in the second sub-coil 1212 in the sub-coil group 121 on the lower portion of the first door panel 10 are both clockwise. The direction of the current in the second sub-coil 1211 and the direction of the current in the second sub-coil 1212 in the sub-coil group 121 on the upper portion of the second door panel 20 are both clockwise, and the direction of the current in the second sub-coil 1211 and the direction of the current in the second sub-coil 1212 in the sub-coil group 121 on the lower portion of the second door panel 20 are both counterclockwise.

[0063] To enable the second transmitting coil assembly 12 to compensate for the Z-axis blind spot of the first transmitting coil assembly 11 and improve the accuracy of coil structure detection results, in some embodiments, the projection of the area between two adjacent first current lines with the same current flow direction in adjacent or intersecting second sub-coils on the plane defined by the Y and Z axes intersects with the projection of the area between two adjacent first current lines with opposite current flows in the first transmitting coil assembly 11 on the plane defined by the Y and Z axes.

[0064] Among them, the two adjacent or intersecting second sub-coils can be two intersecting second sub-coils in the same sub-coil group. Alternatively, they can also be a second sub-coil in each of the two sub-coil groups, and the distance between the two second sub-coils is the shortest. In addition, if the two sub-coil groups intersect, the two second sub-coils also intersect. If the two sub-coil groups are spaced apart, the two second sub-coils are adjacent. Regarding two adjacent first current lines with the same current flow direction, one of the first current lines is located in one second sub-coil, and the other first current line is located in the other second sub-coil. Among them, the intersection of projections includes partial overlap of one, partial overlap of both, and complete coverage. Complete coverage means that all projections of the two are completely intersected. Partial overlap of one means that all projections of one intersect with the projection of the other and some projections of the other do not intersect. Partial overlap of the two means that only some projections of both intersect, which are all within the scope of protection of this application.

[0065] With specific reference to Figures 1, 2, and 5, the process of compensating for the Z-axis blind spot of the first transmitting coil assembly 11 is described using the example of the second transmitting coil assembly 12 on the first door panel 10. Specifically, two adjacent first conducting lines with opposite current directions in the first transmitting coil assembly 11 are conducting lines a and b, which form a Z-axis blind spot A. To compensate for the Z-axis blind spot A formed by the first transmitting coil assembly 11, the two intersecting second sub-coils (i.e., second sub-coil 1211 and second sub-coil 1212) in the upper sub-coil assembly 12 of the second transmitting coil assembly 12 have two adjacent first conducting lines (i.e., conducting lines d and conducting lines i) with the same current flow direction. The partial area between conducting lines d and conducting lines i corresponds to the partial area between conducting lines a and conducting lines b in the first transmitting coil assembly 11, partially overlapping the two areas. Therefore, conducting lines d and conducting lines i can compensate for the Z-axis blind spot A. In addition, the second sub-coil 1212 in the upper sub-coil group 121 is adjacent to the second sub-coil 1211 in the lower sub-coil group 121, and these two second sub-coils have two adjacent first conducting wires (i.e., conducting wire i and conducting wire j). The entire area between conducting wire i and conducting wire j is opposite to the partial area between conducting wire a and conducting wire b, which is a case of partial overlap of one of the above. In this case, conducting wire i and conducting wire j can also compensate for the Z-axis blind area A.

[0066] The manner in which the second transmitting coil group 12 on the second door panel 20 compensates for the Z-axis blind area of ​​the first transmitting coil group 11 is the same as the manner in which the second transmitting coil group 12 on the first door panel 10 compensates for the Z-axis blind area of ​​the first transmitting coil group 11 , and will not be further described here.

[0067] Furthermore, to ensure that the Z-axis blind spot can be completely compensated as much as possible, in the embodiment, the projection of the area between two adjacent first conducting lines with the same current flow direction in two adjacent or intersecting second sub-coils on the plane defined by the Y-axis and the Z-axis covers the projection of the area between two adjacent first conducting lines with opposite current flows in the first transmitting coil assembly 11 on the plane defined by the Y-axis and the Z-axis.

[0068] In this embodiment, two adjacent or intersecting second sub-coils can be located in different sub-coil groups. If the two sub-coil groups are spaced apart, the two second sub-coils are adjacent. If the two sub-coil groups intersect, the two second sub-coils intersect. The projection of the former (such as the area between the two first current lines with the same current flow direction) covers the projection of the latter (such as the area between the two adjacent first current lines with opposite current flow directions in the first transmitting coil group 11) and can include: the entire projection of the latter is within the projection of the former, and the projection area of ​​the former is larger than that of the latter. Alternatively, it can also mean that the projection areas of the two are the same and completely intersect. For example, as shown in FIG10 , the projection of the area between live wires i and j on the plane defined by the Y-axis and the Z-axis completely covers the projection of the area between live wires a and b on the plane defined by the Y-axis and the Z-axis. In other words, the Z-axis position of the area between live wires i and j is exactly the same as the Z-axis position of the area between live wires a and b. This ensures that the Z-axis blind spot A in the first transmitting coil assembly 11 can be completely compensated by the second transmitting coil assembly 12.

[0069] To further improve coil structure detection accuracy, this embodiment also uses the first transmitting coil assembly 11 to compensate for the Z-axis blind spot of the second transmitting coil assembly 12. The projection of the area between two adjacent first current lines in the first transmitting coil assembly 11, with currents flowing in the same direction, on the plane defined by the Y and Z axes, intersects with the projection of the area between two adjacent first current lines in the second transmitting coil assembly 12, with currents flowing in opposite directions, on the plane defined by the Y and Z axes. Projection intersection includes partial overlap, partial overlap, and complete overlap. Complete overlap means that all projections of the two completely intersect. Partial overlap means that all projections of one intersect with the projection of the other, while some projections of the other do not intersect. Partial overlap means that only some projections of the two intersect. All of these are within the scope of protection of this application. Referring to Figures 2, 4, and 5, the blind spot compensation process is described using the first transmitting coil assembly 11 on the first door panel 10 as an example of compensating for the Z-axis blind spot of the second transmitting coil assembly 12. Specifically, the second transmitting coil assembly 12 includes two adjacent first conducting wires with opposite current directions, for example, conducting wires c and d, which have a Z-axis blind spot B. The projection of the area between conducting wires c and d on the plane defined by the Y and Z axes intersects with the projection of the area between conducting wires l and k, two adjacent conducting wires in the first transmitting coil assembly 11, which have the same current flow direction, on the plane defined by the Y and Z axes. Therefore, conducting wires l and k can compensate for Z-axis blind spot B. Furthermore, referring to FIG1 , the projection of the entire area between conducting wires l and k intersects with the projection of a portion of the area between conducting wires c and d, representing a partial overlap.

[0070] The second transmitting coil assembly 12 includes two adjacent first conducting wires, such as conducting wires e and conducting wires f, with currents flowing in opposite directions. This creates a Z-axis blind zone C. The projection of the area between conducting wires e and f on the plane defined by the Y and Z axes intersects with the projection of the area between conducting wires o and p, two adjacent conducting wires in the first transmitting coil assembly 11, with currents flowing in the same direction. Therefore, conducting wires o and p can compensate for the Z-axis blind zone C. Furthermore, referring to FIG1 , the projection of the entire area between conducting wires o and p intersects with the projection of a portion of the area between conducting wires e and f, representing a partial overlap between the two aforementioned areas.

[0071] As can be seen, the first transmitting coil assembly 11 on the first door panel 10 compensates for the Z-axis blind spot of the second transmitting coil assembly 12. The method for compensating the Z-axis blind spot of the second transmitting coil assembly 12 on the second door panel 20 by the first transmitting coil assembly 11 is the same as that for the first door panel 10, and will not be further described here.

[0072] Furthermore, to ensure that blind spots are fully compensated as much as possible, in practice, the projection of the area between two adjacent first current lines with the same current flow direction in the first transmitting coil assembly 11 on the plane defined by the Y and Z axes overlaps the projection of the area between two adjacent first current lines with opposite current flow directions in the second transmitting coil assembly 12 on the plane defined by the Y and Z axes. The projection of the former (e.g., the area between two adjacent first current lines with the same current flow direction in the first transmitting coil assembly 11) overlapping the projection of the latter (e.g., the area between two adjacent first current lines with opposite current flow directions in the second transmitting coil assembly 12) can include: the entire projection of the latter is within the projection of the former, and the projection area of ​​the former is larger than that of the latter, i.e., the projection area of ​​the area between two adjacent first current lines with the same current flow direction in the first transmitting coil assembly 11 on the plane defined by the Y and Z axes is larger than the projection area of ​​the area between two adjacent first current lines with opposite current flow directions in the second transmitting coil assembly 12 on the plane defined by the Y and Z axes. Alternatively, the projection areas of the two projections can be the same and completely intersect.

[0073] For example, as shown in FIG10 , the projection of the area between live wires 1 and k on the plane defined by the Y and Z axes completely overlaps the projection of the area between live wires c and d on the plane defined by the Y and Z axes, ensuring that the Z-axis blind spot B in the second transmitting coil assembly 12 can be completely compensated by the first transmitting coil assembly 11. As described above, the projection of the area between live wires o and p on the plane defined by the Y and Z axes completely overlaps the projection of the area between live wires e and f on the plane defined by the Y and Z axes, ensuring that the Z-axis blind spot C in the second transmitting coil assembly 12 can be completely compensated by the first transmitting coil assembly 11.

[0074] In one embodiment, referring to Figures 1 to 5 above, the coil structure includes two sets of transmitting coil assemblies 1 disposed opposite to each other. The direction of the current flowing through the first transmitting coil assembly 11 of the opposite transmitting coil assemblies 1 switches between the same direction (Figure 3) and the opposite direction (Figure 4), and the direction of the current flowing through the second transmitting coil assembly 12 of the opposite transmitting coil assembly is opposite (Figure 5).

[0075] The two transmitting coil assemblies 1 can be located at the left and right ends, respectively, resulting in two oppositely positioned first transmitting coil assemblies 11 and two oppositely positioned second transmitting coil assemblies 12. It should be noted that the first transmitting coil assemblies 11 and the second transmitting coil assemblies 12 can operate alternately. That is, when the oppositely positioned first transmitting coil assemblies 11 are operating, the oppositely positioned second transmitting coil assemblies 12 are inoperative. When the oppositely positioned second transmitting coil assemblies 12 are operating, the oppositely positioned first transmitting coil assemblies 11 are inoperative. If the currents flowing through the two first transmitting coil assemblies 11 are in the same direction, a superposition field is formed (i.e., operating mode 1), primarily generating X-component magnetic field lines uniformly distributed within the detection channel. As shown in Figure 6, in this mode, there are no blind spots in the magnetic flux lines along the X-axis. If the currents flowing through the two first transmitting coil assemblies 11 are in opposite directions, a repulsive field is formed (operating mode 2). In this mode, the currents in the vertically connected wires in the same column all have the same direction, and no wires in the same column have opposite currents. As shown in Figure 7, there are no blind spots in the magnetic flux lines along the Y-axis. However, regarding the Z-axis magnetic flux lines, a Z-axis blind zone exists in the central region, as shown in Figure 8. If the currents flowing through the two opposing sets of second transmitting coil assemblies 12 are in opposite directions (operating mode three), Z-axis blind zones will be generated in the upper and lower regions. However, because the locations of the Z-axis blind zones in operating mode two (e.g., Z-axis blind zone A) differ from those in operating mode three (e.g., Z-axis blind zone B and Z-axis blind zone C), there is effectively no blind zone in the Z-axis direction, thereby improving detection accuracy.

[0076] In practice, in order to effectively reduce the resistance of the entire coil structure and thus power consumption, and to achieve normal detection without requiring excessively high drive voltages, thereby improving electromagnetic conversion efficiency, in some embodiments, the first transmitting coil assembly 11 is formed by winding a first conductive wire, and the second transmitting coil assembly 12 is formed by winding a second conductive wire, and the first and second conductive wires are connected to the same power interface.

[0077] In the coil structure provided in this embodiment, the first transmitting coil assembly 11 and the second transmitting coil assembly 12 are wound with two separate wires and connected to the same power supply port. That is, the first transmitting coil assembly 11 and the second transmitting coil assembly 12 are arranged in parallel. This effectively reduces the resistance of the entire coil structure and power consumption. Furthermore, it eliminates the need for excessively high drive voltages for proper detection, thereby improving electromagnetic conversion efficiency.

[0078] Based on the coil structure provided above, this embodiment also provides a coil control method. This coil control method can be executed by a processor, a single-chip microcomputer, a controller, or the like. For example, the processor can be electrically connected to the coil structure to control the coil structure to alternately switch between three operating modes, with no particular order of precedence.

[0079] Specifically, the control method includes:

[0080] The control coil structure switches alternately among three working modes.

[0081] Among them, the three working modes include the following.

[0082] Working mode 1: the first transmitting coil group 11 of the relatively arranged transmitting coil groups 1 is controlled to be energized and the second transmitting coil group 12 is controlled to be de-energized, and the directions of the currents flowing through the relatively arranged first transmitting coil groups 11 are the same.

[0083] Working mode 2: the first transmitting coil group 11 in the opposite transmitting coil groups 1 is controlled to be energized and the second transmitting coil group 12 is controlled to be de-energized, and the directions of the currents flowing through the opposite first transmitting coil groups 11 are opposite.

[0084] Working mode three: the first transmitting coil group 11 of the oppositely arranged transmitting coil groups 1 is controlled to be de-energized and the second transmitting coil group 12 is energized, and the direction of the current flowing through the oppositely arranged second transmitting coil group 12 is opposite.

[0085] Specifically, for operating mode one, please refer to Figures 2 and 3 above. In Figure 3, the current direction of the first transmitting coil group 11 on the two door panels is the same, both counterclockwise, forming a superposition field. At this time, in this mode, the magnetic fields of the two door panels are superimposed on each other, mainly generating X-component magnetic field lines uniformly distributed within the detection channel. Figure 6 is a schematic diagram of the magnetic flux lines in the X-axis direction of the coil structure shown in Figure 2 in operating mode one. As shown in Figure 6, there is no blind spot in the magnetic flux lines in the X-axis direction in operating mode one.

[0086] For operating mode two, please refer to Figures 2 and 4 above. In Figure 4, the first transmitting coil assembly 11 on the first door panel 10 rotates counterclockwise, while the first transmitting coil assembly 11 on the second door panel 20 rotates clockwise. The first transmitting coil assemblies 11 on both door panels form a repulsive field. In this mode, the current directions of the vertical conducting wires (such as conducting wire g) in the same column on each door panel are the same, and there are no cases where the current directions of conducting wires in the same column are opposite. Figure 7 is a schematic diagram of the magnetic flux lines along the Y-axis of the coil structure shown in Figure 2 in operating mode two. As shown in Figure 7, there are no blind spots in the magnetic flux lines along the Y-axis.

[0087] In addition, the first transmitting coil group 11 also generates magnetic flux lines in the Z-axis direction. Since the currents in the two horizontal conducting lines a and b of the first sub-coil 114 are in opposite directions, a blind spot for the magnetic flux lines in the Z-axis direction is formed in the middle of the door panels on both sides, namely, the Z-axis blind spot A, as shown in FIG8 . FIG8 is a schematic diagram of the magnetic flux lines in the Z-axis direction of the coil structure shown in FIG2 in operating mode 2.

[0088] Regarding operating mode three, please refer to Figures 2 and 5 above. As shown in Figure 5, the currents flowing through the second transmitting coil assemblies 12 on the two door panels are in opposite directions. Specifically, the currents flowing through the sub-coil assembly 121 on the upper portion of the first door panel 10 and the sub-coil assembly 121 on the upper portion of the second door panel 20 are in opposite directions, and the currents flowing through the sub-coil assembly 121 on the lower portion of the first door panel 10 and the sub-coil assembly 121 on the lower portion of the second door panel 20 are in opposite directions. As shown in Figure 5, the currents flowing through line d of the second sub-coil 1211 and line c of the second sub-coil 1212 are in opposite directions. Therefore, a blind zone for the magnetic flux in the Z-axis direction exists between lines c and d, namely, Z-axis blind zone B. Similarly, a blind zone for the magnetic flux in the Z-axis direction exists between lines e and f, namely, Z-axis blind zone C. This is shown in Figure 9, which is a schematic diagram of the magnetic flux in the Z-axis direction for the coil structure shown in Figure 2 under operating mode three.

[0089] In the solution provided in the embodiment of the present application, the three working modes are executed alternately, which has the following advantages:

[0090] For the X-axis magnetic flux lines, working mode one can generate X-axis magnetic flux lines with no blind spots. For the Y-axis magnetic flux lines, working mode two can generate Y-axis magnetic flux lines with no blind spots. For the Z-axis magnetic flux lines, although in working mode three, the second transmitting coil group 12 will form two blind spots on the Z-axis magnetic flux lines, located at the upper and lower parts respectively, and in working mode two, the first transmitting coil group 11 will generate a blind spot in the middle, but because the blind spot positions of working modes two and three are different, by alternating these three working modes, essentially all areas in the Z-axis direction can also be detected, which is equivalent to having no blind spots in the Z-axis direction. Therefore, the solution provided in the embodiment of the present application can achieve detection without blind spots in the X-axis, Y-axis, and Z-axis directions when a person passes through the detection channel.

[0091] The above describes a coil structure and a coil control method. In this embodiment, the coil structure mentioned above can be applied to a pass-through detector. The pass-through detector includes:

[0092] The door panel structure includes a first door panel 10 , a second door panel 20 and a top panel 30 .

[0093] As described above, the coil structure includes two sets of transmitting coil groups that are arranged opposite to each other. One set of transmitting coil groups 1 is arranged in the first door panel 10 , and the other set of transmitting coil groups 1 is arranged in the second door panel 20 .

[0094] One set of transmitting coils 1 is disposed on the first door panel 10, and another set of transmitting coils 1 is disposed on the second door panel 20. A detection channel (not shown in the drawings) is formed between the first door panel 10, the second door panel 20 and the top panel 30.

[0095] The embodiment of the pass-through detector provided in this embodiment has the same technical features as the coil structure described above. The embodiment of the coil structure has been described in detail above, and the embodiment of the pass-through detector will not be repeated here, and has the same beneficial effects as the coil structure mentioned above.

[0096] The above is a detailed introduction to a coil structure, a pass-through detector, and a coil control method provided by the present application. The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of this application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of this application.

[0097] It should be noted that many of the components mentioned in this application are universal standard parts or components known to those skilled in the art, and their structures and principles can be known to those skilled in the art through technical manuals or conventional experimental methods.

[0098] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0099] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A coil structure, comprising a transmitting coil group, wherein the transmitting coil group comprises a first transmitting coil group and a second transmitting coil group; the first transmitting coil group and the second transmitting coil group are overlapped and placed; The position of the blind area of ​​the magnetic flux lines of the first transmitting coil group in the Z-axis direction is different from the position of the blind area of ​​the magnetic flux lines of the second transmitting coil group in the Z-axis direction, and at least one blind area of ​​the magnetic flux lines in the Z-axis direction is opposite to the intersection area of ​​the first transmitting coil group and the second transmitting coil group.

2. The coil structure according to claim 1, characterized in that: The first transmitting coil group and the second transmitting coil group both include a first conducting line along the Y-axis direction; and a projection of a region between two adjacent first conducting lines with opposite current directions in the first transmitting coil group on a plane formed by the Y-axis and the Z-axis does not intersect or partially intersects with a projection of a region between two adjacent first conducting lines with opposite current directions in the second transmitting coil group on a plane formed by the Y-axis and the Z-axis.

3. The coil structure according to claim 2, characterized in that: The first transmitting coil group includes a plurality of first sub-coils, each of the first sub-coils includes a first conducting wire and a second conducting wire extending along the Z-axis direction, and the first conducting wire is connected to the second conducting wire; the projections of the first sub-coils on the plane formed by the Y-axis and the Z-axis are arranged in a circle, and the directions of the currents flowing through the first sub-coils are the same; The second transmitting coil group includes a plurality of sub-coil groups, each of which is arranged in sequence along the Z axis, and two adjacent sub-coil groups are arranged at intervals or overlapped, and the directions of currents of adjacent sub-coil groups are opposite.

4. The coil structure according to claim 3, characterized in that: Each of the sub-coil groups includes a plurality of second sub-coils whose projections on the plane formed by the Y-axis and the Z-axis intersect, and the current directions of the second sub-coils are the same; the second sub-coil includes the first conducting wire and a second conducting wire along the Z-axis direction; the first conducting wire and the second conducting wire are connected.

5. The coil structure according to claim 4, characterized in that: A projection of an area between two adjacent first conducting lines with the same current flow direction in two adjacent or intersecting second sub-coils on a plane formed by the Y axis and the Z axis intersects with a projection of an area between two adjacent first conducting lines with opposite current directions in the first transmitting coil group on a plane formed by the Y axis and the Z axis.

6. The coil structure according to claim 5, characterized in that: The projection of the area between two adjacent first conducting lines with the same current flow direction in two adjacent or intersecting second sub-coils on the plane formed by the Y axis and the Z axis covers the projection of the area between two adjacent first conducting lines with opposite current directions in the first transmitting coil group on the plane formed by the Y axis and the Z axis.

7. The coil structure according to claim 3, characterized in that: A projection of a region between two adjacent first conducting wires in the first transmitting coil group with the same current flow direction on a plane formed by the Y axis and the Z axis intersects with a projection of a region between two adjacent first conducting wires in the second transmitting coil group with opposite current flow directions on a plane formed by the Y axis and the Z axis.

8. The coil structure according to claim 7, characterized in that: A projection of an area between two adjacent first conducting lines with the same current flow direction in the first transmitting coil group on a plane formed by the Y axis and the Z axis covers a projection of an area between two adjacent first conducting lines with opposite current flow directions in the second transmitting coil group on a plane formed by the Y axis and the Z axis.

9. The coil structure according to claim 1, characterized in that: The coil structure includes two groups of transmitting coil groups arranged opposite to each other, and the direction of the current flowing through the first transmitting coil group in the transmitting coil groups arranged opposite to each other is switched between the same direction and the opposite direction, and the direction of the current flowing through the second transmitting coil group in the transmitting coil groups arranged opposite to each other.

10. The coil structure according to claim 1, characterized in that: The first transmitting coil group is formed by winding a first conductive wire, and the second transmitting coil group is formed by winding a second conductive wire, and the first conductive wire and the second conductive wire are connected to the same power interface.

11. The coil structure according to claim 1, characterized in that: The first transmitting coil group and the second transmitting coil group are completely overlapped.

12. The coil structure according to claim 1, characterized in that: The blind area of ​​the magnetic flux lines of the first transmitting coil group in the Z-axis direction is located between two blind areas of the magnetic flux lines of the second transmitting coil group in the Z-axis direction along the height direction.

13. The coil structure according to claim 1, characterized in that: The position of the blind area of ​​the magnetic flux lines of the first transmitting coil group in the Z-axis direction does not overlap with the position of the blind area of ​​the magnetic flux lines of the second transmitting coil group in the Z-axis direction.

14. A coil structure, comprising a transmitting coil group, wherein the transmitting coil group comprises a first transmitting coil group and a second transmitting coil group; the first transmitting coil group and the second transmitting coil group are completely overlapped; The first transmitting coil group and the second transmitting coil group both include a first conducting line along the Y-axis direction; and a projection of a region between two adjacent first conducting lines with opposite current directions in the first transmitting coil group on a plane formed by the Y-axis and the Z-axis does not intersect or partially intersects with a projection of a region between two adjacent first conducting lines with opposite current directions in the second transmitting coil group on a plane formed by the Y-axis and the Z-axis.

15. The coil structure according to claim 14, characterized in that: The first transmitting coil group includes a plurality of first sub-coils, each of the first sub-coils includes a first conducting wire and a second conducting wire extending along the Z-axis direction, and the first conducting wire is connected to the second conducting wire; the projections of the first sub-coils on the plane formed by the Y-axis and the Z-axis are arranged in a circle, and the directions of the currents flowing through the first sub-coils are the same; The second transmitting coil group includes a plurality of sub-coil groups, each of which is arranged in sequence along the Z axis, and two adjacent sub-coil groups are arranged at intervals or overlapped, and the directions of currents of adjacent sub-coil groups are opposite.

16. The coil structure according to claim 15, characterized in that: Each of the sub-coil groups includes a plurality of second sub-coils whose projections on the plane formed by the Y-axis and the Z-axis intersect, and the current directions of the second sub-coils are the same; the second sub-coil includes the first conducting wire and a second conducting wire along the Z-axis direction; the first conducting wire and the second conducting wire are connected.

17. The coil structure according to claim 16, characterized in that: The projection of the area between two adjacent first conducting lines with the same current flow direction in two adjacent or intersecting second sub-coils on the plane formed by the Y axis and the Z axis intersects with the projection of the area between two adjacent first conducting lines with opposite current flow directions in the first transmitting coil group on the plane formed by the Y axis and the Z axis; Alternatively, the projection of an area between two adjacent first conducting lines with the same current flow direction in two adjacent or intersecting second sub-coils on the plane formed by the Y axis and the Z axis covers the projection of an area between two adjacent first conducting lines with opposite current flow directions in the first transmitting coil group on the plane formed by the Y axis and the Z axis.

18. The coil structure according to claim 15, characterized in that: The projection of the area between two adjacent first conducting wires in the first transmitting coil group with the same current flow direction on the plane formed by the Y axis and the Z axis intersects with the projection of the area between two adjacent first conducting wires in the second transmitting coil group with opposite current flow directions on the plane formed by the Y axis and the Z axis; Alternatively, a projection of an area between two adjacent first conducting lines with the same current flow direction in the first transmitting coil group on the plane formed by the Y axis and the Z axis covers a projection of an area between two adjacent first conducting lines with opposite current flow directions in the second transmitting coil group on the plane formed by the Y axis and the Z axis.

19. A pass-through detector, comprising: A door panel structure, the door panel structure comprising a first door panel and a second door panel; A coil structure, wherein the coil structure comprises two sets of transmitting coil groups arranged opposite to each other, one set of transmitting coil groups is arranged in the first door panel, and the other set of transmitting coil groups is arranged in the second door panel; The coil structure comprises a transmitting coil group, wherein the transmitting coil group comprises a first transmitting coil group and a second transmitting coil group; the first transmitting coil group and the second transmitting coil group are overlapped and placed; The position of the blind area of ​​the magnetic flux lines of the first transmitting coil group in the Z-axis direction is different from the position of the blind area of ​​the magnetic flux lines of the second transmitting coil group in the Z-axis direction, and at least one blind area of ​​the magnetic flux lines in the Z-axis direction is opposite to the intersection area of ​​the first transmitting coil group and the second transmitting coil group.

20. A coil control method, applied to a coil structure, the coil structure comprising two groups of transmitting coil groups arranged opposite to each other, the transmitting coil groups comprising a first transmitting coil group and a second transmitting coil group; the first transmitting coil group and the second transmitting coil group are placed overlapping; The position of the blind area of ​​the magnetic flux lines of the first transmitting coil group in the Z-axis direction is different from the position of the blind area of ​​the magnetic flux lines of the second transmitting coil group in the Z-axis direction, and at least one blind area of ​​the magnetic flux lines in the Z-axis direction is opposite to the intersection area of ​​the first transmitting coil group and the second transmitting coil group; The method comprises: Controlling the coil structure to switch alternately between three working modes; The three working modes include: Working mode 1: controlling the first transmitting coil group in the relatively arranged transmitting coil groups to be energized and the second transmitting coil group to be de-energized, and the directions of the currents flowing through the relatively arranged first transmitting coil groups are the same; Working mode 2: controlling the first transmitting coil group in the relatively arranged transmitting coil groups to be energized and the second transmitting coil group to be de-energized, and the directions of the currents flowing through the relatively arranged first transmitting coil groups are opposite; Working mode three: controlling the first transmitting coil group in the relatively arranged transmitting coil groups to be de-energized and the second transmitting coil group to be energized, and the directions of the currents flowing through the relatively arranged second transmitting coil groups are opposite.

Images