JPH09147249A - Commodity monitoring indicator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin and flexible commodity monitoring indicator which has a flat surface. SOLUTION: This indicator consists of a base material 11 that is primarily made of paper, synthetic resin, etc., an Fe-Si alloy wire 12 contained in the material 11, and the canceling magnetic powder 15 which is mixed in the periphery of the wire 12. The wire 12 is made of an Fe-Si alloy having the Si density of 6 to 7wt.% and has the sudden inversion of magnetization when an alternating magnetic field exceeding its coercive force is applied. The powder 15 is made of a magnetic material that can be magnetized in its hard or semi-hard state and applies a bias magnetic field to the wire 12 to prevent the inversion of magnetization of the wire in its magnetized state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an article monitoring sign used in a system for magnetically monitoring articles such as articles.

[0002]

2. Description of the Related Art A magnetic type article monitoring system uses a switchable magnetic element for a label or the like of an article.
Is provided, and a pulsed output due to magnetization reversal that occurs when an alternating magnetic field is applied to this magnetic sensitive element is detected by a coil or the like. Therefore, in this case, the passage of the article is monitored by providing the inspection gate with an alternating magnetic field generator and a detector for detecting a pulsed output due to the magnetization reversal. As the magnetic sensitive element, an element using an Fe-Co-Si-B based amorphous alloy, an Fe-Ni based alloy, or the like is known.

For example, when the above-mentioned magnetic sensitive element is used to monitor a product in a store, a process of attaching the magnetic sensitive element to the product and canceling the magnetization reversal function of this element at the stage of payment That is, it is necessary to perform processing that does not generate a detection signal even when passing through the inspection gate.

From such a demand, it is proposed to provide a hard or semi-hard canceling magnetic body in the vicinity of the magnetic sensitive element, as in the prior art described in US Pat. No. 3,665,449. Has been done. This prior art is similar to the article monitoring sign 1 shown in FIG.
A plate-shaped or wire-shaped canceling magnetic body 4 is arranged in the vicinity of the magnetic sensitive element 3 buried in the. Then, if necessary, the canceling magnetic body 4 is magnetized, and the magnetic sensitive element 3 is magnetized.
By applying a bias magnetic field to the magnetosensitive element 3, the magnetic sensitive element 3 does not cause magnetization reversal even when an alternating magnetic field is applied to the inspection gate.

[0005]

In the marker 1 having the canceling function as in the above-mentioned prior art, the canceling magnetic body 4 is arranged in the vicinity of the magnetic sensitive element 3, so that the manufacturing cost of the marker 1 is high. Moreover, when the element 3 and the canceling magnetic body 4 overlap in the thickness direction of the sign 1, there is a problem that the thickness of the sign 1 becomes large. In addition, since the surface of the sign 1 has large irregularities, it is difficult to print, for example, a barcode or a product price on the sign 1. Moreover, since the marker 1 itself is not easily bent, it is difficult to attach the marker 1 to a curved surface such as a bottle or a can. Therefore, it is an object of the present invention to provide an article surveillance sign which can be made thin and which is highly flexible and has a substantially flat surface.

[0006]

The article monitoring mark of the present invention developed to achieve the above object has a base material made of a non-magnetic material, and a Si concentration of 6 to 6 provided on the base material.
Fe which is made of 7 wt% Fe-Si alloy and causes a sharp magnetization reversal when an alternating magnetic field exceeding its coercive force is applied
-Si alloy wire and a magnetic substance that is magnetically hard or semi-hard and can be magnetized, and is mixed in the vicinity of the Fe-Si alloy wire of the base material and magnetized in a state of being magnetized. And a magnetic powder for canceling, which gives a bias magnetic field to the magnetization reversal to the alloy wire. F above
The e-Si alloy wire having an absolute value of saturation magnetostriction of 30 × 10 ⁻⁶ or less is recommended.

An example of the above-mentioned base material is a film-like material mainly made of a flexible material such as paper or synthetic resin, but the alloy wire is used as the base material constituting the article to be monitored or the container. The magnetic powder for canceling may be mixed.
Further, a transparent or opaque synthetic resin protective layer may be provided on the front surface side of the film-shaped substrate, and an adhesive layer may be provided on the back surface side of the substrate, and a release paper may be provided on this adhesive layer. . If necessary, product information such as an optically readable bar code and product price is printed on the surface of the sign.

When an alternating magnetic field exceeding the coercive force of the Fe--Si alloy wire is applied, the above-mentioned marker causes a sharp magnetization reversal with almost no magnetostriction due to the large Barkhausen effect (large Barkhausen jump). Therefore, when an alternating magnetic field exceeding the coercive force of the Fe-Si alloy wire is applied to the inspection gate or the like, a sharp magnetization reversal occurs in the Fe-Si alloy wire. A pulse-like output is detected by capturing the change in magnetic field associated with this magnetization reversal with a detector such as a detection coil. Then, by comparing the pulsed output with predetermined reference data or the like, it is possible to determine whether or not the marker is magnetized, that is, whether or not a bias magnetic field is applied to the Fe-Si alloy wire. You can

By magnetizing the canceling magnetic powder as needed, a magnetization reversal of the Fe--Si alloy wire can be prevented by applying a bias magnetic field to the Fe--Si alloy wire. By doing so, the magnetization reversal function of the alloy wire is canceled, and even if an alternating magnetic field is applied to the inspection gate or the like, a pulsed output cannot be detected.

Since the Fe-Si alloy wire causes almost no magnetostriction upon reversal of magnetization, embedding it in the base material does not affect the output. On the other hand, the amorphous ferromagnetic wire and Fe-Ni alloy wire used in conventional shoplifting prevention tags etc. have large magnetostriction, so if they are embedded in the base material, the output will drop extremely, No output can be obtained.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. In an example of the article monitoring sign 10 shown in FIGS. 1 and 2, a Fe-Si alloy wire 12 is embedded in a label-shaped (strip-shaped) substrate 11 made of a non-magnetic material. In addition, a large number of canceling magnetic powders 1 are formed on the substrate 11.
5 is mixed. The magnetic powder 15 will be described later.

A relatively soft material such as paper or synthetic resin is used for the base material 11, and the thickness of the base material 11 is Fe-Si.
If the film-shaped base material 11 having the same diameter as that of the alloy wire 12 is adopted, the sign 10 having a high flexibility can be obtained. As the material of the base material 11, a non-conductive material such as glass or ceramics can be used in addition to paper or synthetic resin.

The sign 10 is preferably provided with an adhesive layer 13 on the back surface side of the substrate 11 so that it can be attached to an article. However, in the case of a hanging tag such as a tag, the adhesive layer 13 can be omitted. Further, as in the sign 10 shown in FIG. 3, it is provided with a protective layer 20 covering the front surface side of the base material 11 and a peelable release paper 21 attached to the adhesive layer 13 on the back surface side of the base material 11. It may be. The sign 10 having the adhesive layer 13 can be attached to a desired position of the product via the adhesive layer 13 by peeling off the release paper 21. Further, like the sign 10 shown in FIG. 4, optically readable product information 27 such as a product identification barcode 25 and a product price 26 is provided on the surface of the sign 10.
May be printed.

The wire-shaped Fe-Si alloy wire 12 is arranged along the longitudinal direction of the base material 11 (the direction in which the marker 10 is magnetically scanned). However, the alloy wire 12 does not necessarily have to be provided at the center of the base material 11 in the width direction, and may be arranged at a position closer to one side. The alloy wire 12 is made of a Fe-Si alloy having a Si concentration of 6 to 7 wt% (more preferably 6.2 to 6.7 wt%). As an example of the size of the Fe-Si alloy wire 12, the wire diameter is 30 to 150 μm (for example, around 50 μm), and the length is 300 to 1000 times the wire diameter (for example, 40 m).
(around m) is recommended. The cross-sectional shape of the alloy wire 12 is preferably a circle, but may be a cross-section other than a circle such as an ellipse, a polygon, or a rectangle.

The Fe--Si alloy wire 12 has a strong magnetic anisotropy in the axial direction due to the magnetic effect of its shape and crystal structure, and the coercive force of the alloy wire 12 (for example, 0.1 to 0.1). When an alternating magnetic field with an amplitude greater than 1.0 Oersted is applied, the large Barkhausen effect causes a very steep magnetization reversal.

When this magnetization reversal is detected by, for example, a solenoid coil, a pulsed output P as shown in FIG.
Is obtained. That is, when the positive coercive force of the Fe-Si alloy wire 12 is Hp and the negative coercive force is -Hp, the Fe-Si alloy wire 12 has the moment when the alternating magnetic field exceeds these coercive forces Hp and -Hp.
Magnetization reversal occurs in the alloy wire 12, and a pulsed output voltage P corresponding to this magnetization reversal is detected. Since the width of this pulse is as small as 10 to 100 μsec, the output voltage contains many high frequency components of several KHz or more. The magnetization reversal hardly depends on the frequency of the alternating magnetic field applied,
Even if the frequency is low, the same pulsed output P can be obtained.

The Fe--Si alloy wire 12 has a length of 3 wire diameters.
If it is 00 times or more, it has a saturation magnetic flux density of about 1.2 to 2.0 times that of an amorphous alloy wire (amorphous wire), so that it is more than a conventional amorphous alloy wire. A large and sufficient output voltage can be obtained. The wire diameter is 30
In the case of an alloy wire of μm to 150 μm, if the length exceeds 1000 times the wire diameter, the size becomes too large to be practical, so the wire length is 300 to 1000 times the wire diameter. It is desirable that the range is set.

Since such an Fe--Si alloy wire 12 is extremely thin and flexible, it can be easily attached to not only articles having a flat surface but also articles having a curved surface such as bottles and cans. it can. Further, since the Fe-Si alloy wire 12 is extremely thin, even if the Fe-Si alloy wire 12 is embedded in the base material 11, the marker 1
Since the surface of 0 is almost flat, it is possible to print the product information 27 such as the barcode 25 as shown in FIG.

A large number of canceling magnetic powders 15 made of a magnetically hard or semi-hard substance are mixed in the base material 11. The material of the magnetic powder 15 has, for example, a coercive force of 10
Γ-Fe ₂ O of about 0 to 5000 oersted (Oe)
₃ and _{Co-γ-Fe 2 O 3} , Fe 3 O 4, Ba ferrite, ferromagnetic materials are suitable, including various ferrites such as Sr ferrite. This magnetic powder 15 is 0.2 μm
Those processed to have a particle size of ˜1.6 μm are suitable. The volume ratio between the base material 11 and the magnetic powder 15 is preferably in the range of about 1: 2 to 3: 1. In the conventional article monitoring label, it is necessary to arrange the plate-shaped canceling magnetic bodies at regular intervals and to arrange the wire-shaped canceling magnetic bodies at a narrow pitch. However, the treatment of mixing the magnetic powder 15 in the base material 11 as in this embodiment can be carried out at a low cost because only the alloy wire 12 is embedded in the base material 11.

When the magnetic powder 15 is magnetized, as shown in FIG.
A bias magnetic field can be applied to the Fe—Si alloy wire 12 as indicated by a two-dot chain line S in FIG. In the case of FIG. 5, the bias magnetic field shifts the alternating magnetic field acting on the Fe—Si alloy wire 12 above the coercive force (−Hp), so that the magnetization reversal does not occur and the pulsed output P does not occur.

FIG. 6 shows an article (commodity) to which the mark 10 is attached.
An inspection gate 40 for monitoring the passage of M is shown. The gate 40 includes a transmitter 42 as a magnetic field applying unit that generates an alternating magnetic field in an inspection area 41 through which a customer passes, and a receiver 43 as a receiving unit that outputs a change in the magnetic field in the inspection area 41 as an output signal. I have.

The transmitter 42 has a transmitting coil 45 and an AC generator 47 for supplying an alternating current to the transmitting coil 45 via an amplifier 46. The transmitting coil 45 generates an alternating magnetic field according to the alternating current supplied from the alternating current generator 47 via the amplifier 46, and applies the alternating magnetic field to the inspection region 41.

The receiver 43 includes a detection coil 50 that functions as an electromagnetic induction coil, and a detection circuit 51 connected to the detection coil 50. The detection coil 50 is disposed facing the transmitting coil 45 at an interval enough to allow a person to pass through, for example, at an interval of 1 m, and forms the inspection area 41 between the detecting coil 50 and the transmitting coil 45. Then, a current corresponding to the magnetic field in the inspection region 41 is induced in the detection coil 50 forming the receiving means, and this current is output to the detection circuit 51 as an output signal.

The detection circuit 51 includes a filter 52 connected to the detection coil 50, an amplifier 53, and a comparator 54. The filter 52 extracts the high frequency component of the pulsed output signal resulting from the steep magnetization reversal of the Fe—Si alloy wire 12 from the output signal received by the detection coil 50. Since the pulsed output periodically appears every time the positive and negative of the alternating magnetic field changes, the detection is performed almost in an instant without moving the article M with the mark 10 relative to the alternating magnetic field.

The comparator 54 compares the detected pulsed output with reference data prepared in advance,
Whether a pulsed output is generated (Fe-Si alloy wire 12
Whether or not the magnetization reversal has occurred), that is, whether or not the canceling magnetic powder 15 is magnetized. Article M
When passing through the gate 40, the canceling magnetic powder 15
If the magnetic field is not magnetized, the receiver 43 and the detection circuit 51 detect a pulsed output.

An informing means 56 is connected to the comparator 54 via a drive section 55. The drive unit 55 activates the notification unit 56 according to the comparison result of the comparator 54. The notifying means 56 notifies the administrator (a clerk or the like) of the gate 40 of the collation result by a display means such as a warning light or a notification sound.

Next, the operation of the marker 10 having the above structure will be described. Signs 10 to monitor goods at shops and the like
When using the mark, the marker 10 is attached to the product in advance. In addition, the inspection gate 40 is installed at the exit of the store, for example, at the exit of a checkout station (so-called cash register). A magnetic field generator (not shown) for magnetizing the canceling magnetic powder 15 is provided at the checkout place. When the customer pays for the product at the checkout point, the canceling magnetic powder 15 of the mark 10 attached to the product is magnetized by the magnetic field generator.

For this reason, the products that have already been paid for are the inspection gates 4.
As the Fe—Si alloy wire 12 does not cause magnetization reversal when passing through 0, this product is allowed to exit the inspection gate 40. In contrast, unchecked products are inspection gate 4
When passing through 0, the Fe—Si alloy wire 12 of the mark 10 attached to the product causes magnetization reversal. Therefore, the above-mentioned pulsed output is detected by the coil 50, and the detection circuit 51 activates the notification means 56 via the drive unit 55.

As shown in FIG. 7, the article M to be monitored is
The canceling magnetic powder 15 is mixed in a part of the base material 11 made of synthetic resin or paper constituting the case, the case, the container, etc., and the Fe—Si alloy wire 12 is mixed in the region where the magnetic powder 15 is mixed. May be buried. In this case, a label 28 printed with product information 27 such as an optically readable barcode 25 and a product price 26 is attached to the surface of the base material 11 of the product M.

[0030]

According to the present invention, since magnetic powder for canceling the magnetization reversal function of the Fe-Si alloy wire is mixed in the base material, the alloy wire is extremely thin and flexible. The flexibility of the sign is not impaired, and the sign can be easily attached not only to an article having a flat surface but also to an article having a curved surface such as a bottle or a can.

Further, the sign can be made thinner than the conventional one, and since the surface of the sign is almost flat, it is possible to print the product information such as the bar code and the product price. Moreover, since the Fe-Si alloy wire has a very small magnetostriction, the desired output can be obtained even when the Fe-Si alloy wire is embedded in the base material. The process of mixing the magnetic powder into the base material can be performed at low cost. Further, by embedding the alloy wire and the magnetic powder for canceling in the base material constituting the article itself or the container, a part of the article can be used as a marker.

[Brief description of the drawings]

FIG. 1 is a perspective view of an article monitoring mark showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is a cross-sectional view showing a modified example of the sign.

FIG. 4 is a plan view showing a modified example of a sign on which a barcode is printed.

5 is a diagram showing the relationship between the excitation magnetic field and the output of the marker shown in FIG.

FIG. 6 is a perspective view showing a configuration of a gate for detecting the marker shown in FIG. 1.

FIG. 7 is a perspective view of an article provided with a sign.

FIG. 8 is a plan view of a conventional marker having a canceling magnetic material.

[Explanation of symbols]

 10 ... Mark for article monitoring 11 ... Base material 12 ... Fe-Si alloy wire 13 ... Adhesive layer 15 ... Magnetic powder for cancellation 20 ... Protective layer 21 ... Release paper 25 ... Bar code 27 ... Product information

Claims (3)

[Claims] 1. A base material made of a non-magnetic material, and Fe- which is provided on the base material and has a Si concentration of 6 to 7 wt%.
An Fe-Si alloy wire formed of a Si alloy that causes a sharp magnetization reversal when an alternating magnetic field exceeding its coercive force is applied, and a magnetic substance that is magnetically hard or semi-hard and can be magnetized. Magnetic powder for cancelling, which is mixed in the vicinity of the Fe-Si alloy wire and gives a bias magnetic field to the alloy wire to prevent magnetization reversal of the alloy wire in a magnetized state, A sign for monitoring goods. 2. The base material is in the form of a film mainly composed of paper or a synthetic resin, a protective layer covering the front surface side of the base material, an adhesive layer provided on the back surface side of the base material, and an adhesive layer. The article monitoring sign according to claim 1, further comprising a release paper attached to the layer. 3. The magnetic powder for canceling is mixed in a part of a base material constituting an article to be monitored or a container in which the article is to be monitored, and the Fe--Si alloy is contained in a region in which the magnetic powder is mixed. The article monitoring sign according to claim 1, wherein a line is embedded.