JPH02228582A - Discriminating apparatus of article - Google Patents

Abstract

PURPOSE:To make it possible to discriminate not only the presence or amount of an article, but also the kind thereof, by fitting a marker to the article. CONSTITUTION:A magnetic marker 20 different in permeability from one another being stuck on each article, an article 21 is made to run on a belt 15, while an AC voltage of a prescribed frequency is impressed on a coil 17 to generate an AC magnetic field. When the magnetic marker 20 passes through an AC magnetic field band 22, the magnetic marker 20 is magnetized and a magnetic flux is generated. By this magnetic flux the substantial inductance of the coil 17 is varied, the resonance frequency of a resonant circuit composed of the coil 17, a capacitor and a resistor is shifted and the value of a current flowing through the resonant circuit is varied. Since the magnitude of the magnetic flux generated by each magnetic marker 20 different in permeability from others is different, the variation in the inductance of the coil 17 is different for each magnetic marker 20 and the maximum variation in the value of the current flowing through the resonant circuit is also different for each magnetic marker 20. This maximum variation in the current value is read and compared in an electronic circuit element 18 and thereby discrimination of the article 21 is enabled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device attached to an article to identify m* or quantity of the article.

[Conventional technology]

It is said that a marker is attached to an article and the marker is used to detect the quantity of the article or to prevent the article from being stolen. For example, an alternating current magnetic field is passed through an article to which an amorphous magnetic ribbon or side edge is attached as a marker, and fluctuations in the magnetic field are detected.This method has been put into practical use as a theft prevention system. FIG. 4 is a schematic diagram of this anti-theft system, and FIG. 5 shows an example of the structure of the anti-theft marker. In FIG. 4, the anti-theft system consists of a marker l attached to the article 2 and a group of measuring instruments arranged to detect the marker l when the marker '1 passes through the interrogation zone 11.

Articles 21, such as clothing, 1t11, etc., are displayed in the store. Each article 2 is attached with a marker l having a configuration as shown in FIG. This marker 1 consists of a ribbon-shaped amorphous ferromagnetic material strip 12 and one or more small magnetized crystal metal ferromagnetic materials 13 on the IJ tube 12. It has become.

If the article 2 is taken out of the store without permission, the article 2 will pass through the interrogation zone 11 located in front of the exit IO, and this interrogation zone 11 is an alternating current magnetic field zone generated by the rescue coil 9. Therefore, the amorphous ferromagnetic strip 12 of the marker 1 attached to the article 2 is magnetized and generates a magnetic flux according to the frequency of the alternating current ffl field, and the horizontal thin coil 8
An identification signal indicating that the marker 1 is present in the interrogation zone 11 is given to the marker 1 .

This identification signal activates an alarm to prevent theft. Incidentally, at this time, the crystalline metal magnetic material 13 of the marker 1 has a high coercive force so as not to be magnetized. - 10,000, if the goods 2 are properly paid for, then at the time of payment the goods 2 are placed in the opening 6 of the deactivation system 4, which is electrically connected to the money increasing machine 3 by means of an electric terminal R5; A magnetic field is applied that is sufficient to permanently magnetize the crystalline metal ferromagnetic material 13 of the marker l. With this magnetization, the amorphous ferromagnetic strip 12 of the marker 1 is biased and the magnetic permeability of the marker 1 is substantially reduced.

In this state, even if the marker l enters the interrogation zone 11, no identification signal is given to the horizontal thin coil 8, so if the article 2 is properly paid and taken out of the store, the article 2
Marker 1 attached to is called m? The alarm will not be activated by passing through the FF area 11.

[Problem to be solved by the invention]

As described above, markers attached to articles have conventionally been used only to detect the presence or absence of the article or the quantity thereof, and cannot recognize the article itself or identify its type. However, for example, in a line where different types of products flow,
A process is required to classify the products according to type, and for this purpose, markers must have this function.

The present invention has been made in view of the above-mentioned points, and its object is to provide an article identification device that can identify not only the presence or absence and quantity of articles, but also the type, by attaching markers to articles. .

1 m] In order to solve the above problems, the article identification device of the present invention has the following components.

1) A belt that stretches along the outer periphery of two pulleys, places an article with a % magnetic marker affixed thereon, and runs the article in a fixed direction.

11) A guide is provided along the entire length of the belt and allows the article to which the marker is affixed to run at a predetermined position on the belt.

(mountain) An exchange &rttB which is placed near the side of the belt and magnetizes the marker affixed to the article when the marker passes.
A coil that forms a field band.

tv > AC power supply that supplies excitation fafi current to this coil.

■) An electronic circuit section that includes a capacitor and a resistor that forms a resonant circuit with the coil and AC power supply, and connects the coil and AC power supply.

[Effect]

When using the apparatus of the present invention, magnetic markers with different magnetic permeability are attached to each article, and the articles are run on a belt.
An alternating current voltage of a constant frequency is applied to the coil to generate an alternating magnetic field. Before the magnetic marker passes through this alternating current magnetic field band, the coil, capacitor, and resistor are adjusted so that they resonate, and when the al magnetic marker passes through the alternating current tap band, the magnetic marker is magnetized and generates magnetic flux. This magnetic flux changes the effective inductance of the coil, shifts the resonant frequency of the resonant circuit made up of the coil, capacitor, and resistor, and changes the value of the current flowing through this resonant circuit. Since the magnitude of the magnetic flux generated differs for each magnetic marker with different magnetic permeability, the change in coil inductance also differs for each magnetic marker.

The maximum change in the current value flowing through the resonant circuit also differs for each magnetic marker. By reading the maximum change in this current value using an electronic circuit and comparing it, the article can be identified.

〔Example〕

The present invention will be explained below based on examples.

Figure 1 is an external view showing the main part configuration of the article identification device of the present invention. In FIG. 1, this device includes a belt 15 stretched between two pulleys 14, a guide 16 is provided along the entire length of the belt 15, and a coil 17 is installed near the side of the belt 16. It includes an electronic circuit section 18 and an AC power source 19 connected to this coil 17.

When identifying an article using this device, the belt 15 is made to run in the direction of the arrow by the rotation of the pulley 14, and a magnetic thin wire or ribbon made of, for example, a CO-based amorphous alloy is placed on the belt 15. When the article 21 with the marker affixed thereon is placed, the magnetic marker also travels in the direction of the arrow along with the belt 15. At this time, the article 21 is placed along the guide 16 so that it always runs at a predetermined position on the belt 15. An alternating current voltage is applied to the coil 17 at a constant frequency by a power source 19 to generate an alternating current magnetic field band 4 in the region indicated by the dotted line. The basic circuit of this device consists of a coil 17. Condens. It consists of a resistor and an AC power source 19, and the capacitor and resistor are included in the electronic circuit section 18 of FIG. 1 along with other equipment (not shown) such as an amplifier. Below, referring to FIG. 1 and @211, the filter 17 and the capacitor n are connected in parallel to the AC power source 19, and before the magnetic marker passes through the AC magnetic field band n, the coil 17.
Capacitor Z3. I[, 24° Adjust so that the AC power supply 19 becomes a resonant circuit.

At this time, the electric current tlt* flowing in this resonant circuit is the resistance U
can be detected from both ends. When the article 4 with the magnetic marker affixed thereto travels in the direction of the arrow along with the belt 15 and enters the AC magnetic field band ρ, the magnetic marker head is magnetized and generates magnetic flux, and the change in magnetic flux causes the inductance of the resonant circuit to increase. As the resonant frequency of the resonant circuit shifts, the current value flowing through the resonant circuit also changes.

The relationship between the value of the current flowing through the resonant circuit and the frequency of the current at that time is shown in the diagram of FIG.

In Fig. 3, the curve showing the relationship between the current value flowing in the resonant circuit and the frequency before the magnetic marker I enters the AC magnetic field band n is B), and the current value at this time is A, and the resonance of the resonant circuit The frequency is fo.

For song *(E2), the current value and resonance frequency of the resonant circuit when a magnetic marker I with a certain value of magnetic permeability enters the alternating current magnetic field band n and the magnetic flux of the magnetic marker m changes as it passes through this band. , and the resonant frequency f of the resonant circuit at that time.

The current value for B changes from human to B.

Similarly, when magnetic markers having different magnetic permeabilities pass through the AC tapping zone n, the curve (a) shifts to curve rt and curve (a) corresponding to the permeability of each magnetic marker. That is, for the resonant frequency f of the resonant circuit,
Initially, before the magnetic marker passes through the alternating current magnetic field band n, the current value of the resonant circuit is A, but the current value of the magnetic marker is %f.
Due to the difference in fi rate, the electric R value varies from A to B, from A to C,
It changes from A to D. Magnetic markers 31 having different magnetic permeability are attached to each article 21, and these are attached to the AC magnetic field band n.
By passing the magnetic marker through the guide 16, the maximum deviation of the resonant frequency of the resonant circuit differs for each magnetic marker.
is provided to keep the peak frequency shift constant for each magnetic marker. Therefore, when the alternating current excitation frequency fo by the coil 17 is constant, the maximum value of the change in the current 11 is different for each magnetic marker, and these values are read by an electronic circuit and the comparison is made to soften the product n to which the magnetic marker is applied. It becomes possible to identify.

〔Effect of the invention〕

Conventionally, a device that detects an article by attaching a marker only knows the presence or absence and quantity of the article, but as described in the embodiment, the device of the present invention detects the magnetic permeability of each article. Attach materials as markers, place them on a belt, and run them one after another, picking up coils, capacitors, and resistors along the way.

Each magnetic marker is magnetized by passing through an AC a-field band excited by a coil of a resonant circuit made up of an AC power source, generating magnetic fluxes of different magnitudes.

Because the maximum change in the current flowing through the resonant circuit for a given resonant frequency of the resonant circuit is different for each magnetic marker, items equipped with these magnetic markers can be used not only to detect presence or quantity, but also to detect This makes it possible to identify even those 11@.

[Brief explanation of the drawing]

Figure WX1 is an external view showing the main part S configuration of the non-inventive device. Fig. 2 is a resonant circuit diagram used in the device of the present invention, Fig. 3 is an Iwao diagram showing the relationship between the current value of the resonant circuit and the frequency of its electric current for magnetic markers with different magnetic permeabilities, and Fig. 4 is a diagram of the resonant circuit used in the device of the present invention. A layout diagram showing each device used in a conventional anti-theft system, and FIG. 5 is an external view of a marker used in the anti-theft system shown in FIG. 14... Pulley, 15... Belt S16... Guide, 17... Coil, 18... Electronic circuit section, 19.
... AC power supply, power supply ... magnetic marker, 21 ... article, n ... father-flow magnetic field band, ... controller circle

Claims (1)

[Claims] 1) i) A belt stretched along the outer periphery of two pulleys, on which an article with a magnetic marker attached is placed, and the article travels in a fixed direction; ii) provided along the entire length of the belt; a guide for causing the article to which the marker is affixed to run at a predetermined position on the belt; iii) an alternating current magnetic field band that is placed near the side of the belt and magnetizes the marker affixed to the article when the marker passes therethrough; iv) an alternating current power source that supplies an exciting current to this coil; v) an electronic circuit section that includes a capacitor and a resistor that forms a resonant circuit with the coil and the alternating current power source, and is connected to the coil and the alternating current power source. An article identification device comprising: