JP2006133085A - Lapse indicator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lapse indicator which has a function to confirm lapse of detection tag and indicate. <P>SOLUTION: The lapse indicator for EM tags has a lapse magnet 2 having a lapse surface 8 formed by arranging S-poles 4 and N-poles 6 of a plurality of magnets by turns, a pair of plane coils 10, 12 arranging in parallel the lapse surface 8 and a coil surface, an output circuit 14 containing the pair of plane coils 10, 12 for taking out the differential output, and a data processor-indicator 16 for detecting higher harmonics from the taken-out differential output of the output circuit 14. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a deactivation device for an EM tag (hereinafter referred to as a detection tag). More specifically, the present invention relates to a hard magnetic layer of a detection tag formed by laminating at least a hard magnetic layer and a soft magnetic layer. The present invention relates to a deactivation device for a detection tag that can demagnetize a detection tag by magnetizing it and surely check the revocation state.

  Conventionally, there is known a magnetic detection tag that is attached to a product etc., moves with the product, and is detected when it passes through a predetermined gate to manage the product or prevent the product from being stolen. (For example, Patent Document 1). Such a magnetic detection tag is called an EM (Electric Magnetic) tag.

  FIG. 7 shows an example of a conventional detection tag. In FIG. 7, reference numeral 60 denotes a soft magnetic layer containing cobalt element or the like. On one surface of the soft magnetic layer 60, a hard magnetic layer 65 having a large number of through holes 63 is laminated via a polyester adhesive layer 62. The hard magnetic layer 65 contains a hard magnetic element such as nickel, for example. A protective layer 67 made of high-quality paper or a resin film is attached to the upper surface of the hard magnetic layer 65.

  A release material 69 is attached to the other surface of the soft magnetic layer 60 via an adhesive layer 68. When the detection tag is used, the release material 69 is peeled off and attached to a product to be managed.

  FIG. 8 shows gates 70 and 72 for detecting the detection tag, and an alternating magnetic field S is formed between the gates 70 and 72. Further, a detector (not shown) for detecting the magnetic field strength is attached to both the gates 70 and 72, and the magnetic field strength between the both gates 70 and 72 is detected by this detector. Reference numeral 74 denotes a detection tag. When the detection tag 74 is attached to a product or the like (not shown) and passes between the gates 70 and 72 as indicated by the arrow R, the magnetic field S formed between the gates 70 and 72 is distorted. By detecting the distortion of the magnetic field S, it is recognized that the detection tag 74 has passed between the gates 70 and 72.

  FIG. 9 shows an example of a specific method for detecting the distortion of the magnetic field. In FIG. 9, (a1) shows a waveform of an AC magnetic field having a constant frequency formed between the gates 70 and 72 in FIG. When the time axis is converted to the frequency axis using a simple mathematical method, the waveform shown in (a2) is converted.

  In FIG. 9, (b1) shows the waveform of the alternating magnetic field distorted by the detection tag 74 passing between the gates 70 and 72. When coordinate axis conversion is performed on the distorted waveform in the same manner as described above, the waveform shown in (b2) is obtained. In the waveform of (b2), harmonics 80 and 82 due to distortion of the alternating magnetic field are recognized. By detecting the presence or absence of this harmonic, the presence or absence of the detection tag 74 passing between the gates 70 and 72 is detected.

  For example, when a product or the like is properly purchased and can be taken out to the outside, a revocation operation is performed on the detection tag 74 attached to the product or the like. By performing this revocation operation, the magnetic field is not distorted even if the detection tag 74 attached to the product passes through the gates 70 and 72. As a result, goods etc. are safely taken outside.

  On the other hand, if the detection tag 74 is not expired when it is illegally taken outside, a distorted magnetic field is generated when goods etc. pass through the gates 70 and 72, and this distorted magnetic field is generated. By detecting this, unauthorized take-out is detected.

  The revocation is achieved by magnetizing the hard magnetic layer 65 of the detection tag shown in FIG. 7 using a deactivation device.

  FIG. 6 shows an example of a conventionally used invalidator. This deactivation device 50 is a base 52 in which disc-shaped permanent magnets having a diameter of 12 mm are arranged at intervals of about 10 mm, and each magnet has alternating N poles 54 and S poles 56. ing.

  When the detection tag shown in FIG. 7 touches the upper surface of the deactivation device 50, the hard magnetic layer 65 is magnetized, thereby deactivating the detection tag.

However, in the detection tag revocation method using the conventional revocation device, not all detection tags are reliably revoked, and there are cases where they are not revoked. In this case, although it is a product obtained by a legitimate procedure, it is detected at the gate and regarded as being obtained illegally, which is a big problem.
JP-A-6-342065 (Claim 1)

  The present inventor can confirm the revocation status of the detection tag subjected to the revocation process by providing a detection circuit having a pair of planar coils in the revocation device while variously examining to solve the above problem. I thought I could solve the problem. The present invention has been completed based on the above findings. Accordingly, an object of the present invention is to provide a detection tag revoker that solves the above problems.

  The present invention for achieving the above object is described below.

  [1] A deactivation magnet having a deactivation surface formed by alternately arranging S poles and N poles of a plurality of magnets, a pair of planar coils in which the deactivation surface and the coil surface are arranged in parallel, and the pair An EM tag deactivation device having an output circuit that includes a flat coil and outputs a differential output thereof, and a data processing / display unit that detects and displays harmonics from the differential output extracted from the output circuit.

  [2] The deactivating device according to [1], wherein a pair of planar coils are disposed on a surface opposite to the deactivating surface of the deactivating magnet.

  [3] The invalidator according to [1], in which an invalid magnet is interposed between the coils of the pair of planar coils.

  [4] The invalidator according to [1], wherein a pair of planar coils are disposed on the invalidation surface.

[5] The deactivation device according to [1], wherein the deactivation surface is formed by a magnet in which strip-shaped S poles and N poles are alternately arranged. [6] The magnet width between the S pole and N pole of the deactivation surface is 12 mm. The invalidator according to [1], which is as follows.

  [7] The invalidator according to [1], wherein the dimension of the invalidation surface is larger than the dimension of the planar coil.

  [8] The invalidator according to [1], wherein the magnetic flux density measured at a distance of 2 mm from the invalidation surface is 0.01 Tesla or more.

  Since the invalidator of the present invention has a detection tag detection circuit including a pair of planar coils, it can be immediately confirmed that the detection tag has expired when the detection tag is expired using this invalidator. For this reason, it is possible to reliably prevent an accident in which an unexpired detection tag is erroneously detected at the gate.

  Furthermore, when using a deactivation magnet in which a deactivation surface is formed by alternately arranging strip-shaped S poles and N poles, the detection tag can be deactivated more reliably than a conventional deactivation device.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows an example of the invalidator of the present invention. FIG. 1A is a side view of a deactivation device, and 2 is a deactivation magnet. The deactivation magnet 2 includes a plurality (three in FIG. 1A) of strip-shaped (rectangular) S poles 4 and a plurality (three in FIG. 1A) of strip-shaped (rectangular) N poles 6. And have revocation surfaces 8 arranged in close contact with each other. FIG. 1B shows a plan view of the invalidator.

  The width P of the strip-shaped S pole 4 and the width Q of the strip-shaped N pole 6 need to be smaller than the short side of the detection tag to be expired. The width P and the width Q are not necessarily the same width, and the magnet widths may be different.

  Specifically, when a detection tag having a standard size of about 16 mm × 26 mm is expired, the widths P and Q are each preferably 12 mm or less, more preferably 1 to 10 mm, and particularly preferably 2 to 8 mm.

  When the widths P and Q are larger than the short side of the detection tag to be revoked, there is a case where the revocation is not reliably performed. Further, the widths P and Q may be 1 mm or less. However, even if the widths P and Q are 1 mm or less, an increase in the revocation effect due to the 1 mm or less is not particularly observed.

  The magnetic flux density of the deactivating magnet 2 is preferably larger from the viewpoint of ensuring the deactivating action. Specifically, the magnetic flux density 2 mm away from the revocation surface 8 is 0.01 Tesla or more, and more preferably 0.02 to 0.1 Tesla.

  As such a deactivation magnet, what is marketed as a flexible magnetic anisotropic sheet can be used. This magnetic anisotropic sheet is produced by a method of kneading a hard magnetic powder such as a ferrite type or a rare earth type containing neodymium with rubber or plastic, followed by extrusion and magnetizing (Japanese Patent Laid-Open No. 2001-297911, Japanese Patent Laid-Open No. 11-293938).

  Further, permanent magnets in which S poles and N poles are formed in a strip shape may be alternately and closely arranged.

  In the above description, the belt-like S pole 4 and N pole 6 are arranged in close contact with each other. However, the present invention is not limited to this, and the S pole 94 and the N pole 96 are spaced from each other as shown in FIG. It may be arranged. The inter-magnet distance V between the S pole 94 and the N pole 96 is preferably 10 mm or less, and more preferably 1 to 5 mm.

  Further, as shown in FIG. 6, a deactivating magnet in which conventional disk-shaped magnets are arranged may be used.

  As shown in FIG. 1 (A), a pair of first planar coil 10 and second planar coil 12 are disposed on the lower surface of the deactivating magnet 2. The first planar coil 10 is disposed in close contact with the lower surface of the deactivation magnet 2, and the second planar coil 12 is arranged in parallel with the first planar coil 10 at a predetermined distance T from the first planar coil 10. It is set up. 11 is a spacer. Although there is no restriction | limiting in particular as the predetermined space | interval T, from a viewpoint of noise prevention, 30 mm or less is preferable and 5-20 mm is more preferable.

  As shown in FIG. 1C, the first planar coil 10 and the second planar coil 12 are loop coils in which an electric wire is spirally wound in a plane, and are rectangular as shown in FIG. What was wound in the shape of a circle, what was wound in a circle, what was wound in the shape of a rhombus, etc. can be used.

The winding direction of the first planar coil 10 and the second planar coil 12 is not particularly limited, but the magnetic field generated by the first planar coil 10 when configuring the detection circuit of the detection tag shown in FIG. It is necessary to connect so that the direction and the direction of the magnetic field generated by the second planar coil 12 cancel each other and output the difference between the outputs of both coils.
By connecting in this way, detection of external noise can be effectively prevented.

  The output circuit 14 amplifies the difference output of the bridge circuit composed of the first planar coil 10, the second planar coil 12, and resistors R 1 and R 2 described later, and supplies the amplified output to the data processing / display unit 16. It is.

  FIG. 2 shows the output circuit 14 of the invalidator shown in FIG. A bridge generated when alternating current power of a predetermined frequency is supplied from the power source E to a bridge circuit constituted by the first planar coil 10, the second planar coil 12, the resistor R1, and the resistor R2, and the detection tag is detected. The differential output of the circuit is amplified by the operation amplifier circuit DA and supplied to the data processing / display unit 16.

  The data processing / display unit 16 performs data processing for extracting the harmonic component of the AC power supplied from the power source E from the output of the output circuit 14 and confirms whether or not the harmonic component is detected. This data processing itself is known. When the harmonic component is not detected, the display unit displays that the detection tag is invalidated. When the harmonic component is detected, the display unit displays that the detection tag is not expired.

  Next, a case where the detection tag is expired using the invalidator shown in FIG. 1 will be described. For example, the hard magnetic layer is not magnetized in the initial state of a detection tag attached to a product or the like at a store. In this state, if the product is illegally taken outside, it is detected at the gate.

  On the other hand, when the price of this product is paid normally, in this state, the detection tag attached to the product is brought close to the revocation surface 8 of the deactivation device, and preferably the hard magnetic layer of the detection tag on the revocation surface 8 The detection tag is brought into contact with the revocation surface 8 while facing each other. As a result, the hard magnetic layer of the detection tag is magnetized, and as a result, the detection tag expires.

  The time for which the detection tag is brought close to the revoked surface in order to make it invalid or the contact time may be short. Specifically, any time may be used as long as it is 0.1 second or longer.

  When the detection tag expires by the above operation, since the harmonic component is not detected during the differential output of the bridge circuit, the data processing / display unit determines that it has expired and displays that fact on the display unit.

  On the other hand, when the revocation fails for some reason, the harmonic component of the AC power supplied to the bridge circuit is sent from the output circuit to the data processing / display unit. The data processing / display unit recognizes this, and displays on the display unit that it has not been revoked.

  The deactivation magnet of the deactivation device has a deactivation surface in which strip-shaped S poles and N poles are alternately arranged. A deactivation device using a deactivation magnet having this structure has a higher deactivation capability of a detection tag than a conventional deactivation device. The reason why the deactivation magnet reliably deactivates the detection tag has not been fully clarified, but the present inventors consider that the demagnetizer composed of the above-described strip-shaped magnetic pole arrangement is because the magnetic flux directions are easily aligned. On the other hand, in the case of a deactivation device in which conventional disk-shaped magnets are arranged, it is considered that the deactivation effect is uncertain because the magnetic flux density is reduced by forming the magnetic flux to diverge in the entire circumferential direction. .

  FIG. 3 shows another configuration example of the invalidator of the present invention.

  In this example, the deactivating magnet 32 is interposed between the pair of first planar coils 34 and the second planar coil 36. As shown in FIG. 3, the first planar coil 34 and the second planar coil 36 may be brought into close contact with the deactivating magnet 32, or the first planar coil 34 and the second planar coil 36 are separated by a predetermined distance, A deactivating magnet 32 may be disposed in the approximate center so as to be separated from the coils 34 and 36.

  The distance between the first planar coil 34 and the second planar coil 36 is preferably 30 mm or less, and more preferably 5 to 20 mm.

  The first planar coil 34 and the second planar coil 36 constitute a bridge circuit so that the direction of the lines of magnetic force are opposite to each other, and other configurations are the same as described above.

  FIG. 4 shows still another configuration example of the invalidator of the present invention.

  In this example, a pair of first planar coil 44 and second planar coil 46 are stacked on the upper surface of the deactivating magnet 42 with a spacer 45 spaced apart by a predetermined distance U. The predetermined interval U is preferably 30 mm or less, and more preferably 5 to 20 mm. The first planar coil 44 and the second planar coil 46 configure a bridge circuit so that the direction of the magnetic force lines are opposite to each other, and other configurations are the same as described above.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples.

Example 1
A commercially available ferrite rubber magnet (trade name anisotropic rubber magnet manufactured by Magtec Co., Ltd.) is cut, and the belt-like N poles and S poles shown in FIG. A deactivating magnet with a different structure was manufactured. The width P of the S pole 4 and the width Q of the N pole 6 were 2 mm, and the length L was 150 mm. The magnetic flux density 2 mm away from the deactivation surface of the ferrite rubber magnet was about 0.03 Tesla. The magnetic flux density was measured with a Gauss meter 5080 (manufactured by FW BELL).

  The electric wire was wound 1200 times in a spiral shape to produce two planar coils having a diameter of 120 mm, which were used as a first planar coil and a second planar coil. As shown in FIG. 1, the 1st planar coil and the 2nd planar coil were arrange | positioned on the lower surface of the deactivation magnet. The distance between the coils was 8 mm. A bridge circuit was constituted by two 470Ω resistors and the two planar coils, and a 20-v AC voltage (306 Hz) was supplied to the bridge circuit. At this time, the magnetic field intensity near the coil was 800 A / m. The magnetic field strength was measured with a Gauss meter GM-003 (manufactured by Electronic Magnetic Industry).

  A detection tag (trade name: EH-026, manufactured by Lintec Corporation) having a structure shown in FIG. 7 having a width of 16 mm and a length of 26 mm was brought into contact with the revocation surface of the deactivation device for 1 second. As a result, all of the 10 detection tags can be reliably revoked, and the display on the display unit indicates that 10 detection tags have been revoked.

  Next, the 10 expired detection tags were sequentially passed through the gate. The gate did not detect any of the 10 detection tags.

Example 2
A deactivation magnet was produced in the same manner as in Example 1 except that a neodymium rubber magnet (trade name rubber magnet manufactured by Magna Co., Ltd.) having S and N pole widths P and Q of 3 mm was used. went. The magnetic flux density 2 mm away from the dead surface was about 0.045 Tesla. The result was that all 10 detection tags could be revoked reliably. The display on the display indicates that 10 detection tags have expired.

  Next, the 10 expired detection tags were sequentially passed through the gate. The gate did not detect any of the 10 detection tags.

Example 3
A deactivating magnet was produced in the same manner as in Example 1 except that a neodymium magnet (trade name Neodymium magnet manufactured by Magna Co., Ltd.) having a width P and Q of S and N poles of 5 mm was used, and the same test was performed. . The magnetic flux density 2 mm away from the dead surface was about 0.08 Tesla. The result was that all 10 detection tags could be revoked reliably. The display on the display indicates that 10 detection tags have expired.

  Next, the 10 expired detection tags were sequentially passed through the gate. The gate did not detect any of the 10 detection tags.

Example 4
A deactivating magnet was produced in the same manner as in Example 1 except that a neodymium magnet having a width P and Q of S and N poles of 10 mm (trade name Neodymium magnet manufactured by Magna Co., Ltd.) was used, and the same test was performed. . The magnetic flux density 2 mm away from the lapsed surface was about 0.095 Tesla. The result was that all 10 detection tags could be revoked reliably. The display on the display indicates that 10 detection tags have expired.

  Next, the 10 expired detection tags were sequentially passed through the gate. The gate did not detect any of the 10 detection tags.

Example 5
A deactivated magnet was produced in the same manner as in Example 1 except that an anisotropic ferrite magnet having a width P and Q of S pole and N pole of 15 mm (trade name ferrite magnet manufactured by Magna Co., Ltd.) was used. Went. The magnetic flux density 2 mm away from the dead surface was about 0.055 Tesla. Eight of the ten detection tags could expire. The display on the display unit indicates that eight detection tags have been revoked and that two detection tags have not been revoked.

  Next, the 10 expired detection tags were sequentially passed through the gate. The gate did not detect any of the eight expired detection tags. However, the gate detected the remaining two stale detection tags. Further, when the two detection tags that have not been revoked are revoked again, the display on the display unit indicates that both of them have been revoked.

Example 6
A commercially available deactivation device having the structure shown in FIG. 6 was used as the deactivation magnet. The disk-shaped ferrite permanent magnets having a diameter of 12 mm were arranged as shown in FIG. 6, and the shortest distance between the disk-shaped magnets was 9 mm. The magnetic flux density 2 mm away from the dead surface was about 0.09 Tesla. A revocation device having an electronic circuit having the configuration of Example 1 was manufactured using this revocation magnet, and a revocation test was performed in the same manner as in Example 1. As a result, 3 out of 10 detection tags expired. The display on the display unit indicates that three detection tags have expired and that seven detection tags have not expired.

  Next, the ten detection tags subjected to the revocation process were sequentially passed through the gate. The gate did not detect any of the three expired detection tags. However, the gate detected the remaining seven non-expired detection tags.

Example 7
A deactivation device having a configuration in which planar coils are attached to both surfaces of the deactivation magnet shown in FIG. 3 was manufactured. The expired magnet, the electronic circuit, etc. used were the same as those used in Example 1, and the first planar coil and the second planar coil were brought into close contact with the expired magnet having a thickness of 5 mm.

  A detection tag (trade name: EH-026, manufactured by Lintec Corporation) having a structure shown in FIG. 7 having a width of 16 mm and a length of 26 mm was brought into contact with the revocation surface of the deactivation device for 1 second. As a result, all of the 10 detection tags can be reliably revoked, and the display on the display unit indicates that 10 detection tags have been revoked.

  Next, the 10 expired detection tags were sequentially passed through the gate. The gate did not detect any of the 10 detection tags.

Example 8
A deactivation device having a configuration in which two planar coils were laminated on the upper surface of the deactivation magnet shown in FIG. The same deactivation magnets and electronic circuits as those used in Example 1 were used.

  A detection tag (trade name: EH-026, manufactured by Lintec Corporation) having a structure shown in FIG. 7 having a width of 16 mm and a length of 26 mm was brought into contact with the revocation surface of the deactivation device for 1 second. As a result, all of the 10 detection tags can be reliably revoked, and the display on the display unit indicates that 10 detection tags have been revoked.

  Next, the 10 expired detection tags were sequentially passed through the gate. The gate did not detect any of the 10 detection tags.

Example 9
As shown in FIG. 5, a deactivation magnet similar to that in Example 1 was manufactured except that the S pole 94 and the N pole 96 were not closely contacted with each other except that a 1 mm inter-magnet distance V was provided, The same test as in Example 1 was performed. The result was that all 10 detection tags could be revoked reliably. The display on the display unit indicates that 10 detection tags have expired.

  Next, the 10 expired detection tags were sequentially passed through the gate. The gate did not detect any of the 10 detection tags.

It is explanatory drawing which shows an example of the invalidator of this invention, (A) is side explanatory drawing, (B) is plane explanatory drawing, (C) is explanatory drawing which shows a planar coil. It is a circuit diagram which shows an example of a structure of the electronic circuit of the invalidator of this invention. It is explanatory drawing which shows the other example of the invalidator of this invention. It is explanatory drawing which shows the further another example of the invalidator of this invention. It is explanatory drawing which shows the further another example of the invalidator of this invention. It is a plane explanatory view showing an example of the conventional invalidator. It is a side view which shows an example of a structure of the conventional detection tag. It is explanatory drawing which shows the detection method of a detection tag. It is explanatory drawing which shows the detection principle of a detection tag, (a) shows the waveform of the alternating current magnetic field formed between gates, (b) shows the waveform of the alternating current magnetic field when a detection tag is detected.

Explanation of symbols

2, 32, 42 Deactivating magnet 4, 56, 94 S pole 6, 54, 96 N pole 8 Deactivating surface 10, 34, 44 First planar coil 11, 45 Spacer 12, 36, 46 Second planar coil 14 Output circuit 16 Data processing / display unit 50 Deactivator 52 Base 60 Soft magnetic layer 62 Adhesive layer 63 Through hole 65 Hard magnetic layer 67 Protective layer 68 Adhesive layer 69 Release material 70, 72 Gate 74 Detection tag 80, 82 Harmonic E Power source DA Operation amplifier circuit L Length P, Q width R Arrow R1, R2 Resistance S Magnetic field T, U Predetermined distance V Distance between magnets

Claims (8)

A deactivation magnet having a deactivation surface formed by alternately arranging S poles and N poles of a plurality of magnets, a pair of plane coils in which the deactivation plane and the coil plane are arranged in parallel, and the pair of plane coils And a data processing / display unit for detecting and displaying harmonics from the difference output taken out of the output circuit. The deactivating device according to claim 1, wherein the pair of planar coils are arranged on the surface opposite to the deactivating surface of the deactivating magnet. The deactivation device according to claim 1, wherein a deactivation magnet is interposed between the coils of the pair of planar coils. The deactivating device according to claim 1, wherein a pair of planar coils are arranged on the deactivating surface. The deactivation device according to claim 1, wherein the deactivation surface is formed of a magnet in which strip-shaped S poles and N poles are alternately arranged. The deactivation device according to claim 1, wherein a magnet width between the S pole and the N pole on the deactivation surface is 12 mm or less. The deactivation device according to claim 1, wherein the dimension of the deactivation surface is larger than the dimension of the planar coil. The deactivation device according to claim 1, wherein the magnetic flux density measured at a distance of 2 mm from the deactivation surface is 0.01 Tesla or more.

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