JP2006047046A - Article inspectable by inspection system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an article inspected by an inspection system for determining whether an article under inspection is authentic or not, and easily handled in shipping. <P>SOLUTION: In the inspection system 2, a ferromagnetic body 17 is previously attached to an authentic article to detect the magnetic characteristics of the ferromagnetic body, thereby determining whether the article under inspection is authentic or not. The system comprises an excitation coil 4 for impressing a magnetic field changing at a prescribed frequency on the article 8 under inspection, a detection coil 6 for detecting a change in magnetic flux density caused by the change in the magnetic field, an FFT calculation part 20 for acquiring a frequency spectrum corresponding to the change in the magnetic field, and a determination part 22 for determining whether the article is authentic or not on the basis of the frequency spectrum. In the ferromagnetic body, sharp reversal of magnetization takes place when a magnetic field exceeding its coercive force is impressed thereon. As to the ferromagnetic body, its frequency spectrum corresponding to a change in magnetic flux relative to a magnetic field changing at a low frequency has a frequency component of large amplitude. The ferromagnetic body has an upper limit value smaller than the weight of a needle detectable by a needle check system. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an article that can be inspected by a system that inspects a product such as a bag, a bag, a wallet, and clothing for the purpose of finding a counterfeit or a cross-flow.

  In recent years, there has been a tendency for imitation and cross-flowing of brand-name products and the like (selling genuine products in a route different from the regular route, for example, a place that does not have a sales license at a factory commissioned for manufacturing). In order to control this, inspections are carried out at customs, etc., but in reality, it is difficult for customs officials to see counterfeit products due to the advancement of imitation, and authentic products are also used for cross-flow products. Because the quality is the same, the detection is virtually impossible.

  In order to reduce the burden of inspection, an IC chip is incorporated in the genuine product in advance, and the information contained in the IC chip, such as the manufacturer and the country of origin, is read by a reader at customs, etc. 2. Description of the Related Art An inspection system is known in which it can be determined whether or not an inspection target product is a cross-flow product, and an inspection target product in which an IC chip is not incorporated can be determined as a counterfeit product.

  In Patent Document 1, a ferromagnetic material is embedded in a security paper such as securities, an alternating magnetic field is applied to the safety paper, a change in magnetic flux density caused by this is detected, and the change in the magnetic flux density is detected. There is disclosed a true / false determination device that obtains a corresponding frequency spectrum and determines whether the safety protection paper is authentic or not based on whether or not the frequency spectrum matches a frequency spectrum prepared in advance.

In Patent Document 2, a crystalline metal fiber having a circular cross section obtained by melt spinning an alloy containing 80% by weight or more of iron is attached to an object to be monitored, and the object is an excitation coil and a detection coil. There is disclosed a monitoring system for detecting a high frequency component of an output signal induced in a detection coil due to a sharp magnetization reversal of a metal fiber caused by passing through an object detection unit incorporating a.
JP-A-8-199498 Japanese Patent Application Laid-Open No. 3-198195

  However, the IC chip is expensive and is therefore reflected in the price of the article, and the inspection system to be used must be complicated.

  Therefore, an object of the present invention is to provide an article that can be detected by an inspection system that can be easily inspected by attaching a relatively inexpensive ferromagnetic material and that is easy to handle at the time of shipment. .

  In order to achieve the above object, in the first aspect of the article according to the present invention, whether a product to be inspected is a genuine product by attaching a ferromagnetic material to a genuine product and detecting the magnetic characteristics of the ferromagnetic material. It is an article to which a ferromagnetic material having a lower limit value of the weight that can be detected by the inspection system for determining whether or not is attached. The inspection system includes a magnetic field application unit that applies a magnetic field that changes at a predetermined frequency to the inspection target product, a magnetic flux detection unit that detects a change in magnetic flux density due to the magnetic field change, and a frequency spectrum corresponding to the magnetic flux density change. Frequency spectrum acquisition means to be acquired, and determination means for determining whether or not the inspection target product is a genuine product based on the frequency spectrum acquired by the frequency spectrum acquisition means. Ferromagnetic materials cause a steep magnetization reversal when a magnetic field exceeding the coercive force is applied, and are smaller than the weight of the needle that can be detected by a meter reading system that detects whether or not a needle is present in the target object. The value is the upper limit of weight.

  The second aspect of the article according to the present invention is the inspection for determining the attribute of the inspection object by attaching a ferromagnetic material having the same material and different shape to the plurality of the same article when the attribute of the article is different. An article to which a ferromagnetic material having a lower limit of weight that can be detected by the system is attached. The inspection system includes a magnetic field application unit that applies a magnetic field that changes at a predetermined frequency to the inspection target product, a magnetic flux detection unit that detects a change in magnetic flux density due to the magnetic field change, and a frequency spectrum corresponding to the magnetic flux density change. Frequency spectrum acquisition means for acquiring, frequency spectrum acquired by applying the same magnetic field change as the magnetic field change to a sample of the same material and shape as the ferromagnetic material, and the attribute of the article to which the ferromagnetic material is attached A determination unit configured to determine an attribute of the inspection object based on the frequency spectrum acquired by the frequency spectrum acquisition unit. The upper limit value of the weight of the ferromagnetic material is smaller than the weight of the needle that can be detected by the meter reading system that detects whether or not the needle is present in the meter reading target product.

  According to the first aspect of the article of the present invention, a ferromagnetic material that causes a sharp magnetization reversal when a magnetic field exceeding the coercive force is applied is attached in advance to a genuine product. The inspection system acquires a frequency spectrum by applying an alternating magnetic field to the inspection target product. This ferromagnetic material is not only a paramagnetic material and a diamagnetic material, but is different from a general ferromagnetic material in which a relatively gentle magnetization reversal occurs, and responds to a change in magnetic flux density for a magnetic field changing at a low frequency. The frequency spectrum has a high frequency component with a large amplitude. As a result, it can be easily determined whether the inspection target product is a genuine product. Furthermore, since the ferromagnetic material attached to the article is smaller in weight than the needle used when the sewing process is included in the manufacture of the article, it is not mistaken for the needle in the inspection process when the article is shipped, and the handling of the article is not necessary. Easy.

  According to the second aspect of the article according to the present invention, ferromagnetic materials having the same material and different shapes are attached to the same article when the attributes (for example, producers) of the article are different. The inspection system obtains a frequency spectrum by applying an alternating magnetic field to the inspection object, and compares it with a frequency spectrum sample acquired in advance for samples of the same material and shape as each ferromagnetic material. Determine the attributes of. As a result, the user of the system can check whether the inspection target product is not a cross-flow product based on the determination result. Furthermore, as in the first aspect, the ferromagnetic material attached to the article is not mistaken for a needle in the inspection process when the article is shipped.

  Embodiments according to the present invention will be described below with reference to the accompanying drawings.

First Embodiment FIG. 1 shows an inspection system for inspecting a first embodiment of an article according to the present invention. This system 2 is a system for determining whether or not the target product is a genuine product by attaching a predetermined ferromagnetic material to the genuine product in advance and detecting the magnetic characteristics of the product to be inspected. Specifically, the inspection system 2 detects an excitation coil (magnetic field generation means) 4 for generating a magnetic field and a magnetic flux density generated in parallel with the excitation coil 4 and generated by the magnetic field generated by the excitation coil 4. The excitation and detection coils 4 and 6 are arranged so as to face the region 10 on which the entire inspection target product 8 or a part thereof is placed. A core having a high magnetic permeability may be inserted in the center of the exciting coil 4. Excitation and detection coils 4 and 6 may be arranged so as to sandwich the mounting area 10. The exciting coil 4 is connected to a low frequency oscillator 12, whereby an alternating current is applied to the exciting coil 4 to generate a periodically changing magnetic field H.

The detection coil 6 is connected to a frequency analyzer 16 via an amplifier 14. If an inspection object 8 is not placed in the region 10 and an alternating current is applied to the excitation coil 4, the detection coil 6 causes the periodically changing magnetic flux density B = μ ₀ H (μ ₀ is a vacuum permeability). A voltage signal (analog signal) corresponding to the magnetic susceptibility is output to the amplifier 14. On the other hand, when the ferromagnetic material 17 is attached to the inspection object 8 placed in the region 10, the ferromagnetic material 17 has a magnetic polarization represented by magnetization M = χH (χ is a magnetic susceptibility). As a result, the magnetization M changes periodically. A curve representing the relationship between the magnetic field H and the magnetization M is called a magnetization curve. In general, χ is not a constant in a ferromagnet (that is, χ varies depending on H), and the magnetization curve is obtained with respect to a periodically changing magnetic field H. Thus, a non-linear closed curve called a hysteresis loop as shown in FIGS. For this reason, the detection coil 6 outputs to the amplifier 14 a voltage signal corresponding to the magnetic flux density B = M + μ ₀ H (MKSA EH compatible unit system) that periodically changes.

  In this embodiment, the ferromagnetic material 17 attached to the genuine product is a crystalline metal fiber having a circular cross section formed by melt spinning an alloy containing 80% by weight or more of iron. In this metal fiber, for example, as shown in FIG. 2 (a), when a magnetic field exceeding the coercive force is applied, a steep magnetization reversal occurs (see Japanese Patent Application Laid-Open No. 3-198195 filed by the present applicant). .

  The frequency analyzer 16 includes an A / D converter 18 that converts the analog voltage signal amplified by the amplifier 14 into a digital voltage signal, and an FFT (Fast Fourier transform) that obtains frequency spectrum data by Fourier transforming the digital voltage signal. ) A calculation unit (frequency spectrum acquisition means) 20 is provided. When the frequency spectrum data is represented by a graph with the horizontal axis representing frequency and the vertical axis representing amplitude, for example, as shown in FIGS. 3A and 3B, the frequency (excitation frequency) of the low-frequency oscillator 12 (for example, 60 Hz) and Amplitude peaks appear at multiples of that frequency. However, paramagnetic materials, diamagnetic materials, and the like, since M is proportional to H (the magnetic susceptibility χ is constant), frequencies other than the excitation frequency do not appear, and for example, a comparatively gentle as shown in FIG. Even in a general ferromagnet that causes a reversal of magnetization, the frequency spectrum does not have a high-frequency component whose amplitude exceeds a certain level as shown in FIG. 3B (the amplitude peak at a frequency that is a multiple of the excitation frequency is low). .) On the other hand, in the said metal fiber, as shown to Fig.3 (a), a frequency spectrum has a high frequency component.

  The frequency analyzer 16 is connected to a determination unit 22 for determining whether the inspection target product 8 is a genuine product. The determination unit 22 is a storage unit (database) 23 that stores frequency spectrum sample data obtained by applying a magnetic field of the same excitation frequency prior to inspection with respect to a sample of the same material and shape as the ferromagnetic material attached to the genuine product. The sample data is compared with the frequency spectrum data output from the FFT calculation unit 20 of the frequency analyzer 16 to determine whether the inspection target product 8 is a genuine product. For example, when the frequency spectrum sample data stored in the storage unit 23 and the amplitude of the high frequency component of the newly acquired frequency spectrum data are substantially equal, the determination unit 22 determines that the inspection target product 8 is a genuine product. judge. The determination unit 22 is connected to a determination result output unit 24 for notifying a user (for example, a customs officer) of the inspection system 2 of the determination result via a buzzer or the like.

  Instead, the determination unit 22 includes, for example, a high-pass filter with a cutoff frequency of, for example, 10 kHz, and the inspection target product 8 is genuine when the filtered frequency spectrum data includes a high-frequency component with an amplitude equal to or greater than the threshold value. You may determine that there is.

  In the inspection system 2 having such a configuration, when a low-frequency alternating current is applied from the low-frequency oscillator 12 to the excitation coil 4 with the entire inspection target product 8 or a part thereof being placed on the region 10, an alternating magnetic field is obtained. H is generated. As a result, the detection coil 6 outputs an analog signal corresponding to the periodically changing magnetic flux density B to the amplifier 14. This analog signal is amplified by the amplifier 14, digitally converted by the A / D converter 18, and then Fourier-transformed by the FFT operation unit 20, and as a result, frequency spectrum data is obtained. The determination unit 22 compares this data with the frequency spectrum sample data acquired in advance, and determines whether or not the inspection target product 8 is a genuine product. The determination result is provided to the user of the system 2 via the determination result output unit 24.

  According to the present embodiment, not only a paramagnetic material and a diamagnetic material but also a comparatively gentle magnetization can be obtained by attaching to the genuine product the metal fiber 17 that undergoes steep magnetization reversal when a magnetic field exceeding the coercive force is applied. Unlike a general ferromagnet in which inversion occurs, a frequency spectrum corresponding to a change in magnetic flux density has a high-frequency component with a large amplitude for a magnetic field that changes at a low frequency. Whether or not can be easily determined.

  It is preferable to fix the position and orientation of the metal fiber 17 to the article and to inform the system user in advance of the position and orientation of the metal fiber. For example, when attaching to a jacket, as shown in FIG. 1, when the metal fiber 17 is attached along the sleeve in parallel with the cuff and the user places the inspection object 8 in the region 10, the excitation and detection coils 4, The metal fiber 17 with respect to 6 takes a predetermined direction. In this state, a frequency spectrum is acquired and compared with the frequency spectrum stored in advance in the storage unit 23 for the sample in the predetermined direction. This is because the peak value of the frequency spectrum differs when the orientation of the metal fiber is different. However, if the frequency spectrum data is obtained after the sample is oriented in various directions prior to inspection, the amount of data to be stored in the storage unit 23 increases, but the user activates the inspection target product 8 with the excitation and detection coils. It is possible to inspect even if it is placed in the region 10 without considering the direction with respect to 4 and 6.

  The object to which the metal fiber is attached can be any article such as a textile product, clothing, bag, wallet, belt, miscellaneous goods, tape, container, and tool. In particular, in the case of textile products, by sewing a very small amount of metal fibers into the textile product, the textile product itself can be provided with a function to prevent imitation, rather than attaching metal fibers to quality and price labeling labels. Furthermore, it has the effect of making it difficult to prevent imitation. Since the metal fiber is flexible, the original function and texture of the fiber product are not impaired. When long fibers (filaments) are used as the metal fibers, they may be monofilaments or multifilaments. Long fibers can be used as a substitute for sewing thread in bags, wallets, belts, sundries, etc., and have a reinforcing effect.

  When consigning production of an article, it is desirable to provide the producer with metal fibers in an amount corresponding to the number of articles produced. Even if the producer makes a counterfeit product of the same quality as the authentic product with the remainder of the material, the counterfeit product cannot be attached to the counterfeit product, so that the counterfeit product can be found using the inspection system 2. In order to prevent the producer from improperly changing the direction of attachment of the metal fiber to the article, in a state where the metal fiber is sewn into the sheet-like fabric used for the display label or the like, the attachment position / orientation being fixed to the article It may be provided to the producer.

  When sewing into a textile product, the fiber diameter of the metal fiber varies depending on the sewing position, but is 200 μm or less, preferably 100 μm or less. When it exceeds 200 μm, rigidity is developed, and when the metal fiber is sewn into a sheet-like fabric, the texture changes and it feels a little hard. In addition, since it will become thin too much and it will be difficult to handle when it becomes 1 micrometer or less, it is preferable that it is larger than 1 micrometer. The fiber length of the metal fiber is 40 mm or more, preferably about 50 mm, although it varies depending on the sewing position. However, it is also possible to use metal fibers as long fibers. In this case, if the texture does not change, it can be used as a multifilament.

  As described above, an amorphous fiber (amorphous metal fiber) having a square hysteresis characteristic may be used instead of the metal fiber as a ferromagnetic material that causes a sharp magnetization reversal when a magnetic field exceeding the coercive force is applied. Good.

  By the way, a needle (hand-sewn needle) used when sewing an article with a needle-reading device (meter-reading system) before shipment for an article attached with a ferromagnetic material that causes a sharp magnetization reversal when a magnetic field exceeding the coercive force is applied. In this application, it is inspected whether there are any remaining needles (sewing needles, waiting needles, etc.) (meter reading process). The meter reading system is for detecting a needle of a predetermined weight or more made of steel (an Fe-C alloy containing iron and carbon of 2% or less, and an alloy added with a third element if necessary). . The size of the ferromagnetic material attached to the article has an upper limit that is detectable by the meter reading system and smaller than the needle used to sew the article, and thus is strong when the article is read by the meter reading system. The magnetic material does not respond to the meter reading system (in other words, prevents the ferromagnetic material from being mistaken as a needle in the meter reading process). On the other hand, if the ferromagnetic material attached to the article is too small, the ferromagnetic material will not react to the inspection system 2, so the weight of the ferromagnetic material has a lower limit value that can be detected by the inspection system 2. .

  FIG. 4 shows an example of a meter reading system. The meter-reading system 30 includes a transport belt 34 for transporting a meter-read target product 32 (a bag in the example in the figure), and a permanent magnet 36 disposed to face the transport belt 34. The permanent magnet 36 is magnetized in a direction (vertical direction in the figure) perpendicular to the conveyance belt 34 so that the conveyance belt 34 side becomes an N pole or an S pole (N pole in the figure). The permanent magnet 36 is surrounded by a high-permeability magnetic shield 37 except for the N pole side so that a DC magnetic field having a predetermined magnetic field strength is formed in the N pole side space of the permanent magnet 36. An electromagnet may be used in place of the permanent magnet 36 as means for generating a DC magnetic field. A detection coil 38 is disposed in a DC magnetic field formed in the N pole side space of the permanent magnet 36 so that the magnetic flux of the DC magnetic field generated by the permanent magnet 36 is linked. The detection coil 38 is connected to the determination unit 42 via the amplifier 40. The detection coil 38 outputs to the amplifier 40 a voltage signal (analog signal) corresponding to the number of magnetic fluxes generated by the permanent magnet 36 and interlinked with the detection coil. Assuming that the meter-reading object 32 includes a remaining needle, when the meter-reading object 32 is transported along the transport belt 34 in a region where the permanent magnet 36 and the detection coil 38 face each other, a DC magnetic field generated by the permanent magnet 36 is used. If there is a remaining needle in the moving meter-reading object 32, the distribution state of the magnetic flux changes depending on the remaining needle (in other words, the number of magnetic fluxes linked to the detection coil 38 changes). The amplifier 40 amplifies the voltage signal detected by the detection coil 38 and outputs it to the determination unit 42. The determination unit 42 is for determining whether or not the remaining needle is included in the meter-reading target product 32. If the peak of the voltage signal amplified by the amplifier 40 is not less than a predetermined threshold value, the meter-reading target It is determined that the needle remains in the product 32. The determination unit 42 is connected to a determination result output unit 44 for notifying a user (for example, a shipping manager) of the meter reading system 30 of the determination result via, for example, a buzzer.

  Generally, the production of an article includes a sewing process, but needles used at the time of sewing include hand-sewn needles (cotton needles, gas needles, silk needles, silk needles, meriken needles), sewing needles, and waiting needles. Regarding each needle of hand-sewn needles, the smallest is a cotton needle of about 170 mg (JIS standard No. 5), a gas needle of about 170 mg (JIS standard No. 9), and a heel needle of about 98 mg (JIS standard No. 5), The silk thread is about 39 mg (JIS standard No. 13), and the Meriken needle is about 45 mg (JIS standard No. 9). The waiting needle is about the same size as a hand-sewn needle. The sewing needle is larger than the hand-sewn needle, and even if the sewing needle is broken, the broken piece is usually larger than the smallest one of the hand-sewn needles. Therefore, by setting the upper limit of the weight of the ferromagnetic material attached to the article to about 30 mg, the peak of the magnitude of the voltage signal amplified by the amplifier 40 with respect to the ferromagnetic material becomes smaller than a predetermined threshold, and the meter reading system 30 It can prevent that the determination part 42 misidentifies that a needle | hook exists in the meter-reading object 32. FIG. In addition, when using the metal fiber mentioned above as a ferromagnetic material, the weight ratio of iron is 80% or more. If the weight ratio of iron is close to 100%, the weight of iron is smaller than 30 mg, so that misidentification with a needle is reliably prevented. In the case of the above-described metal fiber having a smaller iron weight ratio, if the weight of the metal fiber is about 30 mg, the iron weight is smaller than 30 mg, so that misidentification with the needle is surely prevented. Even if it is (for example, about 35-40 mg), since the weight of iron is about 30 mg at most, misidentification with a needle | hook can be prevented.

Second Embodiment An inspection system for inspecting a second embodiment of an article according to the present invention has substantially the same configuration as the inspection system 2 shown in FIG. This makes it possible for the user of the system to determine whether or not the target product has been distributed through a regular route.

  Specifically, crystalline metal fibers having a circular cross section formed by melt spinning an alloy containing 80% by weight or more of iron as a ferromagnetic material are attached in advance to a plurality of the same articles (for example, textile products). Each article is provided with a ferromagnetic material having a different shape when the attribute (for example, the producer) of the article is different (the material is the same). Referring to FIG. 5, for example, depending on the producer, one metal fiber may be linear or L-shaped as shown in (a) and (b), or shown in (c) and (d). Make one or more notches in the metal fiber, or attach one or more knots to the metal fiber as shown in (e), (f), or (g), (h) As shown, the two metal fibers are attached to the article in a state where they are linearly parallel or crossed. In addition, although a short fiber is used suitably as a metal fiber, a long fiber may be sufficient and a monofilament or a multifilament may be sufficient in this case. A frequency spectrum sample is acquired for a sample of the same material and shape as such a metal fiber, and is stored in the storage unit 23 of the determination unit 22 together with the attribute of the article. In the frequency spectrum, an amplitude peak appears at the excitation frequency and a frequency that is a multiple of the excitation frequency, but the peak value varies depending on the shape of the metal fiber. At the time of inspection, the frequency spectrum of the inspection target product 8 is acquired in the same manner as described in the first embodiment, and the determination unit 22 acquires the frequency spectrum and the sample acquired in advance for the sample based on this spectrum. The attribute of the inspection object 8 is determined by referring to the storage unit 23 that stores the relationship with the attribute of the article to which the ferromagnetic material of the same material and shape is attached. An example of the determination result output unit 24 is a monitor that displays an attribute of an article such as a producer.

  Thus, according to this embodiment, since the attribute of the inspection target product can be determined, the user confirms, for example, who the producer of the inspection target product is based on the determination result. It can be confirmed whether it is a product. In addition, since the same material is used as the ferromagnetic material (no different material is attached to each article), the manufacturing cost of the ferromagnetic material attached to the article can be reduced.

  In the present embodiment, unlike the first embodiment, the ferromagnetic material does not need to cause a sharp magnetization reversal when a magnetic field exceeding its coercive force is applied, and has a general strength that causes a gentle magnetization reversal. Magnetic materials are also possible.

  Similarly to the first embodiment, in this embodiment, in order to reduce the amount of frequency spectrum sample data stored in the storage unit 23, the attachment position / orientation of the ferromagnetic material to the article is constant, and the ferromagnetic material It is preferable to inform the user of the position / orientation in advance.

  Similarly to the first embodiment, this embodiment also sets the upper limit value to a value that cannot be detected by the meter reading system (for example, the meter reading system 30 in FIG. 4) as the weight of the ferromagnetic material attached to the article. This prevents the ferromagnetic material from reacting to the meter reading system when the item is read by the meter reading system. On the other hand, if the ferromagnetic material attached to the article becomes too small, the ferromagnetic material will not react to the inspection system according to the present embodiment, so the weight of the ferromagnetic material is set to a value that can be detected by the inspection system. This is the lower limit.

  Although specific embodiments according to the present invention have been described above, the present invention is not limited to these and can be variously modified. For example, in the above-described embodiment, the magnetic coil 6 is used as magnetic flux detection means for detecting a change in magnetic flux density in the inspection system 2, but a Hall element, an MR (magneto-resistive) element, or the like may be used instead.

  With respect to the meter reading system 30, it is unknown at which position of the meter-reading object 32 the needle remains (especially when the object-to-be-inspected 32 is relatively thick) and the relative position of the remaining needle and the conveyor belt 34 (position of the center of gravity). The peak of the magnitude of the voltage signal output from the detection coil 38 is also different when the difference is also included. Therefore, various relative positions of the smallest needle used in the sewing process (for example, one silk thread of about 39 mg (JIS standard No. 13)) with respect to the conveyor belt 34 are set, and the meter reading system 30 performs meter reading. The peak of the magnitude of the voltage signal output from the detection coil 38 may be obtained in various ways, and the smallest of these peaks may be used as a threshold value as a determination criterion of the determination unit 22.

  When the ferromagnetic material contains a metal, the meter reading system is not limited to the above-described magnetic induction type, but an electromagnetic induction type (so-called metal detector) is also possible.

The block diagram which shows the inspection system for inspecting 1st Embodiment of the articles | goods based on this invention. (A) Magnetization curve at room temperature is shown for Fe 93.5 wt% -Si 6.5 wt% metal fiber having a circular cross-sectional diameter of 70 μm and a length of 50 mm. (B) As a comparative example, a magnetization curve at room temperature is shown for a Fe 20 wt% -Ni 80 wt% metal fiber having a circular cross-sectional diameter of 120 μm and a length of 50 mm. (A) and (b) are frequencies obtained when a magnetic field having an excitation frequency of 60 Hz and a magnetic field amplitude of 5 Oe (Oersted) is applied at room temperature to a metal fiber having the characteristics shown in FIGS. The spectrum is shown (the amplitude of 0 dBm corresponds to the case where the impedance is 600Ω and 1 mW of power is consumed). The lineblock diagram showing an example of the meter-reading system for meter-reading the 1st embodiment of the article concerning the present invention. The figure which shows the example of the shape of the ferromagnetic material attached to articles | goods in the inspection system for inspecting 2nd Embodiment of the articles | goods concerning this invention.

Explanation of symbols

2 Inspection system 4 Excitation coil (magnetic field generation means)
6 Detection coil (magnetic flux detection means)
8 Product to be inspected 16 Frequency analyzer 17 Ferromagnetic material 22 Judgment unit 30 Meter reading system 32 Product to be inspected

Claims (7)

A ferromagnetic material having a lower limit of weight that can be detected by an inspection system that determines whether or not an inspection target product is a genuine product by attaching a ferromagnetic material to the genuine product and detecting the magnetic characteristics of the ferromagnetic material. In an article with a body attached,
Inspection system is
A magnetic field applying means for applying a magnetic field that changes at a predetermined frequency to a product to be inspected;
Magnetic flux detection means for detecting a change in magnetic flux density due to the magnetic field change;
Frequency spectrum acquisition means for acquiring a frequency spectrum corresponding to the magnetic flux density change;
A determination unit that determines whether the inspection target product is a genuine product based on the frequency spectrum acquired by the frequency spectrum acquisition unit;
With
The ferromagnetic material causes a sharp magnetization reversal when a magnetic field exceeding the coercive force is applied,
The above-mentioned ferromagnetic material is characterized in that the upper limit value of the weight is a value smaller than the weight of the needle that can be detected by the meter-reading system that detects whether or not the needle is present in the meter-reading object.   2. The article according to claim 1, wherein the upper limit of the weight of the ferromagnetic material is 30 mg.   3. The article according to claim 1, wherein the ferromagnetic material is a crystalline metal fiber having a circular cross section made of an alloy containing 80% by weight or more of iron.   The determination means includes a storage unit that stores a frequency spectrum sample acquired by applying the same magnetic field change as the magnetic field to a sample of the same material and shape as the ferromagnetic material, and acquires the frequency spectrum sample. The article according to any one of claims 1 to 3, which is compared with a frequency spectrum obtained by means. The magnetic field applying means applies a magnetic field changing at a low frequency,
The determination means includes a high-pass filter, and when the frequency spectrum related to the inspection target product after filtering by the high-pass filter includes a high-frequency component whose amplitude is greater than or equal to a threshold value, the inspection target product is determined to be a genuine product. The article according to any one of claims 1 to 3.   The article according to any one of claims 1 to 5, wherein the article is a textile product, and the metal fibers are sewn into the textile product. For a plurality of same articles, when the attributes of the articles are different, a ferromagnetic material having the same material and different shape is attached, and the lower limit value of the weight that can be detected by the inspection system for determining the attributes of the inspection object is provided. In an article with a ferromagnetic body attached,
Inspection system is
A magnetic field applying means for applying a magnetic field that changes at a predetermined frequency to a product to be inspected;
Magnetic flux detection means for detecting a change in magnetic flux density due to the magnetic field change;
Frequency spectrum acquisition means for acquiring a frequency spectrum corresponding to the magnetic flux density change;
A storage unit is provided for storing the relationship between the frequency spectrum obtained by applying the same magnetic field change to the sample of the same material and shape as the ferromagnetic material and the attribute of the article to which the ferromagnetic material is attached. Determining means for determining the attribute of the inspection object based on the frequency spectrum acquired by the frequency spectrum acquiring means;
With
The above-mentioned ferromagnetic material is characterized in that the upper limit value of the weight is a value smaller than the weight of the needle that can be detected by the meter-reading system that detects whether or not the needle is present in the meter-reading object.

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