JP5195565B2 - Detection tag, storage medium, and detection system - Google Patents

Description

  The present invention relates to a detection tag, a storage medium, and a detection system.

  There is a system that detects unauthorized take-out of an article by applying a magnetic material that causes a sharp magnetization reversal when an alternating magnetic field is applied to the article in advance (for example, Patent Documents 1 and 2). In the article management system of Patent Document 1, the canceling function of the magnetic material is canceled by providing a canceling magnetic material in the vicinity of the magnetic material. Patent Document 2 discloses a shape and material suitable for causing a steep magnetization reversal of a magnetic material when an alternating magnetic field is applied.

JP 2003-182847 A Japanese Patent Laid-Open No. 08-305971

  The present invention relates to a detection tag capable of providing a magnetic material with a magnetic characteristic that produces a large Barkhausen effect when an alternating magnetic field is applied without using a special device, a storage medium having the detection tag, and It is an object to provide a detection system having a detection tag.

  The detection tag according to claim 1 of the present invention includes a magnetic body and processing means for processing the magnetic body so as to produce a large Barkhausen effect when an alternating magnetic field is applied.

  In the detection tag according to claim 2 of the present invention, the magnetic body has a foil shape, and the processing means has a blade member for cutting the magnetic body.

  In the detection tag according to claim 3 of the present invention, the processing means cuts the magnetic body so that a horizontal length is 1/10 or less with respect to a vertical length.

  In the detection tag according to claim 4 of the present invention, the magnetic body is formed of an Fe-based amorphous soft magnetic material.

  A storage medium according to a fifth aspect of the present invention includes a housing provided with the detection tag according to any one of the first to fourth aspects, and a storage unit that is provided in the housing and stores information. And a switching unit that is linked to the processing unit and can switch permission and prohibition of writing of information to the storage unit, and when the switching unit is switched to a write-prohibited state, the processing unit The magnetic body is processed.

  A detection system according to a sixth aspect of the present invention includes the detection tag according to any one of the first to fourth aspects, a magnetic field application unit that applies an alternating magnetic field to a magnetic body of the detection tag, Whether the magnetic body is processed by the processing means based on at least one of the width and amplitude of the signal waveform of the response signal and a signal detection unit that detects a response signal emitted from the magnetic body to which an alternating magnetic field is applied Determining means for determining whether or not the detection tag has been detected when the magnetic body is processed by the processing means.

  According to the first aspect of the present invention, magnetic characteristics that generate a large Barkhausen effect when an alternating magnetic field is applied can be imparted to a magnetic material as needed without using a special device.

  According to the second aspect of the present invention, the magnetic material can be easily processed as compared with the case without this configuration.

  The invention of claim 3 can improve the detected performance as compared with the case where this configuration is not provided.

  According to the invention of claim 4, it is easier to give the magnetic material a magnetic property that causes a large Barkhausen effect than in the case where the present configuration is not provided.

  According to the fifth aspect of the present invention, the large Barkhausen effect can be produced in the magnetic material in a state where writing of information to the storage medium is prohibited.

  According to the sixth aspect of the present invention, it is possible to notify that a magnetic material processed so as to produce a large Barkhausen effect when an alternating magnetic field is applied is detected.

(A) is a top view which looked at the detection tag before the magnetic body foil was cut | disconnected from the upper direction regarding the detection tag of 1st Embodiment. (B) is a BB line sectional view of Drawing 1 (A). (C) is CC sectional view taken on the line of FIG. 1 (A). (A) is the fragmentary sectional top view which looked at the detection tag which shows the state which is cutting the magnetic body foil of the detection tag of 1st Embodiment from upper direction. (B) is the BB sectional drawing of FIG. 2 (A). (A) is the fragmentary sectional top view which looked at the detection tag after the magnetic body foil of the detection tag of 1st Embodiment was cut | disconnected from upper direction. (B) is a BB line sectional view of Drawing 3 (A). (A) is a diagram which shows the hysteresis loop of the amorphous magnetic material which produces the large Barkhausen effect. (B) is a diagram showing an alternating magnetic field applied to an amorphous magnetic material. (C) is a diagram showing a response signal generated by an amorphous magnetic material to which an alternating magnetic field is applied. It is a schematic block diagram for demonstrating the detection system of 1st Embodiment. (A) is a diagram which shows the hysteresis loop of a magnetic body foil, and the hysteresis loop of a magnetic body piece. (B) is a diagram showing a waveform of a response signal of the magnetic foil when an alternating magnetic field is applied. (C) is a diagram which shows the waveform of the response signal of the magnetic piece which cut | judged magnetic body foil. (A) is related with the detection tag of 2nd Embodiment, and is the top view which looked at the detection tag before magnetic body foil is cut | judged from the upper direction. (B) is the BB sectional drawing of FIG. 7 (A). (A) is a partial cross-sectional enlarged view showing a state in which the magnetic foil of the detection tag of the second embodiment is being cut. (B) is a partial cross-sectional enlarged view showing a state after cutting the magnetic foil of the detection tag of the second embodiment. (A) It is related with the detection tag of 3rd Embodiment, and is the top view which looked at the detection tag provided in the flexible disk from upper direction. FIG. 10B is an enlarged view showing a state before the magnetic foil of the detection tag of FIG. (C) It is an enlarged view which shows the state after the magnetic body foil of the detection tag of FIG. 9 (B) was cut.

[First embodiment]
A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1A shows a partial cross-sectional plan view of the detection tag 10 according to the present embodiment in an initial state (a state before a magnetic foil to be described later is cut) as seen from above, and FIG. 1 shows a cross-sectional view taken along the line BB in FIG. 1A, and FIG. 1C shows a cross-sectional view taken along the line CC in FIG. 1A. As shown in FIG. 1, the detection tag 10 is provided on a housing 12 made of resin, a foil-like magnetic body foil 20 (an example of a magnetic body) disposed inside the housing 12, and the housing 12. And a cutting mechanism 30 (an example of processing means) that cuts (processes) the magnetic foil 20 into a size that produces a large Barkhausen effect.

  Here, the large Barkhausen effect will be briefly described with reference to FIG. The large Barkhausen effect has BH characteristics as shown in FIG. 4A, that is, an amorphous material made of a material having a relatively small hysteresis loop and a relatively small coercive force Hp, for example, Fe-Co-B-Si. This is a phenomenon that causes a sharp magnetization reversal when a magnetic material is placed in an alternating magnetic field having an amplitude greater than the coercive force Hp. For example, when an alternating current is passed through the exciting coil and an alternating magnetic field having an amplitude equal to or greater than the coercive force Hp is applied to the amorphous magnetic material, the amorphous magnetic material repeats steep magnetization reversal. At this time, a sharp magnetization reversal of the amorphous magnetic material is detected as an electrical pulse-like response signal by the detection coil. A case where an alternating magnetic field as shown in FIG. 4B is applied to the amorphous magnetic material will be described. When an alternating magnetic field is applied to the amorphous magnetic material, a pulsed current flows through the detection coil, and a pulsed output voltage as shown in FIG. 4C is obtained.

  The material of the magnetic foil 20 includes a soft magnetic material, but it is preferable to use an Fe-based amorphous magnetic material having a basic composition of Fe—Co—Si as a magnetic material that easily generates a large Barkhausen effect.

  The Fe-based amorphous magnetic material has a size suitable for producing a large Barkhausen effect. In a cutting mechanism 30 described later, a magnetic piece 22 having a size that produces a large Barkhausen effect by cutting the magnetic body foil 20 is obtained. A plurality are formed. Here, the size suitable for generating the large Barkhausen effect is a size in which the horizontal length L2 is 1/10 or less with respect to the vertical length L1 of the magnetic piece 22, and this ratio is expressed as follows. More preferably, it is 1/100 or less and 1/1000 or less. In addition, since the magnetic piece 22 has a size in which the above ratio is 1/10 or less, the shape is a wire shape (line shape) or a belt shape.

The magnetic foil 20 of the present embodiment is made of an Fe-based amorphous magnetic material (composition: Fe—Co—B—Si), is a square having a thickness of 25 μm, a length of 50 mm, and has a hardness of The Vickers hardness is 1000 GN / m ³ . And as for the size of the magnetic body piece 22 cut | disconnected by the below-mentioned cutting mechanism 30, the vertical length L1 (length in a longitudinal direction) is 50 mm, and the horizontal length L2 is 5 mm.

  As shown in FIGS. 1A to 1C, a magnetic foil 20 is attached to the back surface 12B of the top surface 12A of the housing 12, and the magnetic foil 20 is parallel to the top surface 12A. It is exposed through a plurality of slits 14 formed as described above. The slits 14 are arranged at intervals such that the magnetic foil 20 can be cut to the above-described size (in this embodiment, the slits 14 are arranged so that the centers are at intervals of 5 mm). Moreover, in this embodiment, although the magnetic body foil 20 is affixed on the back surface 12B with the adhesive agent, if the magnetic body foil 20 is fixed inside the housing | casing 12, for example, a magnetic body will be interposed via a plate member etc. The foil 20 may be pressed against the back surface 12B and fixed, or the magnetic foil 20 may be directly fixed to the back surface 12B with a screw or the like.

  In addition, an adhesive layer 12 </ b> C for attaching the detection tag 10 to various articles is provided on the bottom surface of the housing 12. In this embodiment, the adhesive layer 12C is provided on the bottom surface of the housing 12 in order to attach the detection tag 10 to various articles. However, if the detection tag 10 can be attached to various articles, the detection tag 10 is removed. You may fix with a screw | thread etc., pinch and fix with a clip, and you may provide a storage space in the goods side and store in there.

The cutting mechanism 30 includes a substantially rectangular parallelepiped slider 34 disposed on the upper surface 12 </ b> A of the housing 12, and the slider 34 is disposed such that the longitudinal direction is orthogonal to the extending direction of the slit 14. ing. Further, a plurality of cutters 36 (the same number as the slits 14) extending downward are provided on the lower surface of the slider 34 at intervals in the longitudinal direction. These cutters 36 are inserted through the slits 14, respectively, and their tips are located at least below the lower surface of the magnetic foil 20. In addition, these cutters 36 are preferably made of metal (in this embodiment, capable of cutting the magnetic foil 20 having a Vickers hardness of 1000 GN / m ³ ) in order to cut the magnetic foil 20. In the initial state of the detection tag 10 shown in FIGS. 1A and 1B, the slider 34 is in a first position where the cutter 36 is not in contact with the magnetic body foil 20, and is a first stopper (not shown). The movement of the slider 34 is suppressed. The first stopper (not shown) may be formed of an elastic body, or may be formed of a resin that plastically deforms when the slider 34 moves from the first position.

  Further, a part of the slit 14 and the cutter 36 (in this embodiment, both the outer slit 14 and the cutter 36 corresponding thereto) is provided with a detachment prevention mechanism for preventing the slider 34 from being detached from the housing 12. It has been. This detachment prevention mechanism is composed of a concave portion 14A provided in the slit 14 and a convex portion 36A provided in the cutter 36 that engages with the concave portion 14A. In the present embodiment, the slider 34 is prevented from being detached from the casing 12 by engaging the concave portion 14A and the convex portion 36A. However, the present invention is not limited to this configuration, and the slider 34 is not limited to this configuration. Any other configuration may be used as long as it can be prevented from coming off.

  As shown in FIGS. 2A and 2B, the slider 34 is moved from the first position along the extending direction of the slit 14 toward the end of the slit 14 (the lower end in the drawing) (in the X direction). The cutter 36 cuts into the magnetic foil 20.

  Then, as shown in FIGS. 3A and 3B, when the slider 34 is moved along the X direction to the second position that is the end of the slit 14, the magnetic foil 20 is cut. Thereby, a plurality of magnetic body pieces 22 are formed. Further, when the slider 34 is moved to the second position, the movement for returning the slider 34 to the first position is suppressed by a second stopper (not shown).

  Next, the detection system 50 for detecting the detection tag 10 of the present embodiment will be described. FIG. 5 shows a schematic configuration of the detection system 50 according to the present embodiment. The detection system 50 includes the detection tag 10 described above and a detection device 51 that detects the detection tag 10. As will be described in detail later, the detection device 51 includes a gate antenna 52, a warning lamp 54 (an example of a notification unit), and a controller 56 (an example of a determination unit) that controls the operation thereof.

  As shown in FIG. 5, the detection system 50 is provided in a room S such as an office or a store. In the present embodiment, a security gate 62 is disposed at the entrance of the room S, and a person goes out of the room S to the outside. Sometimes it passes through the security gate 62.

  The security gate 62 is provided with the gate antenna 52 and the warning lamp 54 of the detection device 51. When a person detects the detection tag 10 when passing through the security gate 62, the controller 56 lights or blinks the warning lamp 54. It is supposed to let you. Note that the notification method is not limited to this, and it may be performed by an alarm or voice, or may be displayed on a display provided in a preset location. A combination of notification means may be used.

  The gate antenna 52 has an exciting coil 64 that generates an alternating magnetic field by electric power (AC power) supplied from the controller 56, and a magnetic material (the magnetic foil 20 and the magnetic piece 22 for the alternating magnetic field generated by the exciting coil 64. ) Includes a detection coil 66 for detecting a response signal. That is, a current corresponding to an alternating magnetic field generated by the exciting coil 64 is induced in the detection coil 66 and a current corresponding to a response signal generated by the magnetic material (the magnetic material foil 20 and the magnetic material piece 22) is induced. .

  The controller 56 has a filter (not shown) that removes a low-frequency component corresponding to the period of the alternating magnetic field from the current induced in the detection coil 66. The controller 56 includes a high-pass filter 58 that allows passage of the response signal emitted from the magnetic piece 22 and removes the response signal emitted from the magnetic foil 20 among the signals that have passed through the above-described filter. Yes. Specifically, as shown in FIG. 6A, the hysteresis loop (broken line in the figure) of the magnetic foil 20 is a hysteresis loop of the magnetic piece 22 that produces a large Barkhausen effect when an alternating magnetic field is applied. Compared with (solid line in the figure), the gradient of the magnetization characteristic is gentle. For this reason, when the alternating magnetic field shown in FIG. 4C is applied to the magnetic foil 20, the waveform of the response signal has a small amplitude and a wide waveform width as shown in FIG. The waveform width of the magnetic foil 20 is shown as the waveform width W1). On the other hand, when the alternating magnetic field shown in FIG. 4C is applied to the magnetic piece 22, the waveform of the response signal has a large amplitude and a narrow waveform width as shown in FIG. 6C. (In the figure, the waveform width of the magnetic piece 22 is shown as the waveform width W2.) For these reasons, the high-pass filter 58 allows the signal having the waveform width W2 to pass and prevents the signal having the waveform width W1 from passing. Then, the controller 56 determines that the detection tag 10 has been detected when the response signal passing through the high-pass filter 58 matches, and sends a detection signal to the warning lamp 54 so that the warning lamp 54 is lit or blinked. It has become.

  In the high-pass filter 58, the value of the waveform width W2 that allows passage may be given a slight width, and similarly, the value of the waveform width W1 that does not allow passage may also be given a slight width. Good. At this time, in order to make the high-pass filter 58 function reliably, the difference in the waveform width between the magnetic body foil 20 and the magnetic body piece 22 is increased with respect to the vertical length of the magnetic body foil 20. It is preferable to increase the ratio of the horizontal length to the vertical length of the magnetic piece 22 rather than the ratio of the horizontal length.

  The controller 56 may always be in an operating state (a state in which an alternating magnetic field is generated), or an optical sensor or the like is provided in the security gate 62 to detect the passing timing of personnel using this optical sensor. It may shift to an operating state.

Next, the operation of the first embodiment will be described.
When the slider 34 of the detection tag 10 is in the first position, that is, when the magnetic foil 20 is not cut and the detection tag 10 is held and passes through the security gate 62, the excitation by the excitation coil 64 of the gate antenna 52 is alternated. A magnetic field is applied to the magnetic foil 20, and the response signal is detected by the detection coil 66. At this time, since the waveform of the response signal of the magnetic foil 20 is removed by the high-pass filter 58, the controller 56 determines that the detection tag 10 is not detected. For this reason, when the slider 34 of the detection tag 10 is in the first position, the warning lamp 54 does not light up or blink.

  When the slider 34 of the detection tag 10 is moved to the second position and the magnetic foil 20 is cut to form the magnetic piece 22 and passes through the security gate 62 again, the alternating magnetic field generated by the excitation coil 64 is changed to the magnetic substance. When applied to the piece 22, the magnetic piece 22 produces a large Barkhausen effect. The pulse-like response signal emitted from the magnetic piece 22 that has caused the large Barkhausen effect is detected by the detection coil 66 and passes through the high-pass filter 58. Then, the controller 56 determines that the detection tag 10 has been detected, and sends the result to the warning lamp 54 as a detection signal. As a result, the warning lamp 54 does not light up or flashes. In other words, the detection tag 10 has different detection results depending on whether the internal magnetic body is in the state of the magnetic foil 20 or in the state of the cut magnetic body piece 22.

[Second Embodiment]
Next, 2nd Embodiment of the detection tag of this invention is described based on FIG.7 and FIG.8. In addition, about the same member as 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted. FIG. 7A shows a partial cross-sectional view of the detection tag 80 according to the present embodiment in an initial state (a state before the magnetic foil 20 is cut) as seen from above, and FIG. FIG. 7A is a cross-sectional view taken along line BB in FIG.

  As shown in FIGS. 7A and 7B, a detection tag 80 according to the second embodiment includes a resin casing 82 and a magnetic foil 20 disposed inside the casing 82. And a cutting mechanism 90 (an example of processing means) that is provided in the housing 12 and cuts (processes) the magnetic foil 20 into a size that produces a large Barkhausen effect.

  A circular opening 82B is formed in the central portion of the upper surface 82A of the housing 82, and a base portion 92 having a plurality of grooves 94 formed in parallel is provided on the lower surface inside the housing 82. Yes. On the upper surface of the base portion 92, the magnetic foil 20 is attached and covers the plurality of grooves 94. In addition, the grooves 94 are arranged at intervals such that the magnetic foil 20 can be cut into the size of the magnetic piece 22. In the present embodiment, the magnetic foil 20 is attached to the upper surface of the base portion 92 with an adhesive. However, if the magnetic foil 20 is fixed inside the housing 12, for example, via a plate member or the like. The magnetic foil 20 may be pressed against the upper surface of the base portion 92 and fixed, or the magnetic foil 20 may be directly fixed to the upper surface of the base portion 92 with a screw or the like.

  Further, an adhesive layer 82C for attaching the detection tag 80 to various articles is provided on the bottom surface of the housing 82. As long as the detection tag 80 can be attached to various articles, the detection tag 80 may have any configuration as in the first embodiment.

  The cutting mechanism 90 includes a support member 96 having a main body portion disposed inside the housing 82 and above the magnetic body foil 20, and is disposed between the support member 96 and the base portion 92 so as to support the base portion 92. A spring 98 as an urging means for urging 96 upward (separating direction), and a plurality of cutters 100 (as many as the grooves 94) provided on the lower surface of the support member 96 and extending downward. .

  A columnar protrusion is provided at the center of the support member 96, and this protrusion protrudes outside the housing 82 through the opening 82 </ b> B.

Each of the cutters 100 is disposed at a position corresponding to the groove 94, and the length in the longitudinal direction is set longer than the length of the magnetic foil 20, so that the magnetic foil 20 can be cut. Further, when the support member 96 is pushed downward, the tip of the cutter 100 is set so as to be positioned below at least the lower surface of the magnetic foil 20. In addition, the cutter 100 is preferably made of metal (in this embodiment, capable of cutting a magnetic foil having a Vickers hardness of 1000 GN / m ³ ) in order to cut the magnetic foil 20. In the initial state of the detection tag 80 shown in FIG. 7, the support member 96 is in a first position where the cutter 100 does not contact the magnetic foil 20, and is below the support member 96 (Z direction) by a first stopper (not shown). ) Is suppressed. The first stopper (not shown) may be formed of an elastic body, or may be formed of a resin that plastically deforms when the support member 96 moves in the Z direction.

  As shown in FIG. 8A, when the protrusion of the support member 96 is pushed to move the support member 96 in the Z direction, the tip of the cutter 100 is pressed against the magnetic foil 20 and the magnetic foil 20 is cut. Further, when the pressing of the button part is stopped, the support member 96 is pushed upward by being pushed by the spring 98 (upward in the Z direction).

Next, the operation of the second embodiment will be described.
As shown in FIG. 8, in the detection tag 80, the magnetic member 20 is cut by the cutter 100 by pressing the support member 96 through the protrusions, so that the magnetic piece 22 is formed. For this reason, since the magnetic body foil 20 can be cut by an operation of pushing the support member 96 through the protrusion, the user's operation is simplified.

  In the second embodiment, the support member 96 is biased by the spring 98. However, the present invention is not limited to this configuration. After the support member 96 is pushed in, the support member 96 is a stopper. It is good also as a structure which does not return to the original position by being caught in etc. By doing so, the state of the detection tag 80 (whether the magnetic foil 20 is cut) can be visually determined.

[Third embodiment]
Next, 3rd Embodiment of the detection tag of this invention is described based on FIG. In addition, about the same member as 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  As shown in FIGS. 9A to 9C, the detection tag 110 of the present embodiment is provided on a casing 122 of a general flexible disk 120 (hereinafter referred to as FD 120) as a storage medium. . The slider 34 of the detection tag 110 is integrated with an information writing prevention slider 112 (in this embodiment, an example of a switching unit) that is generally provided in the FD 120. Specifically, the first position of the slider 34 (the state in which the magnetic foil 20 is not cut) corresponds to the write permission position to the storage unit 124 of the FD 120, and the second position (the magnetic foil 20 is cut). Corresponds to the write-protection position in the storage unit 124 of the FD 120. Note that a reading device (not shown) for reading information on the FD 120 optically detects the position of the slider 34 and determines whether or not writing of information to the FD 120 is permitted.

Next, the operation of the third embodiment will be described.
After the user stores the confidential information in the FD 120, the slider 34 is moved from the first position to the second position. Thereby, writing of information to the FD 120 is prevented, and the detection tag 110 is detected by the detection device 51. That is, the magnetic foil 20 of the detection tag 110 is cut into the magnetic piece 22 and is detected by the detection device 51. Thereby, when the FD 120 storing the confidential information is about to be taken out from the room S, the warning lamp 54 is turned on or blinked, and it is understood that the confidential information is being taken out by mistake. In addition, since the detection tag 110 cuts the magnetic foil 20 into the magnetic piece 22, the magnetization characteristic that causes the large Barkhausen effect once applied is not lost, and external leakage of confidential information is effective. Will be suppressed.

  In the third embodiment, the detection tag 110 is provided in the housing 122 of the FD 120. However, the present invention is not limited to this configuration, and may be provided in another storage medium. Examples of other storage media include a magneto-optical disk and a magnetic tape.

  The embodiments of the present invention have been described with reference to the embodiments. However, these embodiments are merely examples, and various modifications may be made without departing from the scope of the invention. It goes without saying that the scope of rights of the present invention is not limited to these embodiments.

10 detection tag 20 magnetic foil (magnetic material)
22 Magnetic body piece (processed magnetic body)
30 Cutting mechanism (processing means)
36 Cutter (blade member)
50 detection system 54 warning light (notification means)
56 controller (determination means)
64 Excitation coil (magnetic field application unit)
66 Detection coil (signal detection part)
80 detection tag 90 cutting mechanism (processing means)
100 cutter (blade member)
110 Detection tag 120 Flexible disk (storage medium)
122 Case 124 Storage unit W1 Waveform width W2 Waveform width

Claims (6)

Magnetic material,
Processing means for processing the magnetic body to produce a large Barkhausen effect when an alternating magnetic field is applied;
Detection tag with The magnetic body is foil-shaped,
The detection tag according to claim 1, wherein the processing means includes a blade member that cuts the magnetic body.   The detection tag according to claim 2, wherein the processing means cuts the magnetic body so that a horizontal length is 1/10 or less with respect to a vertical length.   The detection tag according to claim 1, wherein the magnetic body is made of an Fe-based amorphous soft magnetic material. A housing provided with the detection tag according to any one of claims 1 to 4,
A storage unit provided in the housing for storing information;
In conjunction with the processing means, a switching unit capable of switching permission and prohibition of writing information to the storage unit,
Have
When the switching unit is switched to a write-prohibited state, the processing unit processes the magnetic body. The detection tag according to any one of claims 1 to 4,
A magnetic field application unit that applies an alternating magnetic field to the magnetic body of the detection tag;
A signal detector for detecting a response signal emitted by the magnetic body to which the alternating magnetic field is applied;
A determination unit that determines whether the magnetic body is processed by the processing unit based on at least one of a width and an amplitude of a signal waveform of the response signal;
Informing means for informing that the detection tag is detected when the magnetic body is processed by the processing means;
Having a detection system.

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