JP2019179435A - Magnetic identification sensor and magnetic identification device - Google Patents

Abstract

To provide a magnetic identification sensor and a magnetic identification device capable of simultaneously reading a magnetic print pattern on a medium and determining a coercivity level of the medium with simple magnetizing means and one magnetic detection element.SOLUTION: A sensor body 4 includes a sliding member 5, magnets 7 and 8, and a magnetic detection element 9 disposed immediately below the sliding member 5, and is disposed between a transport paths 10 and 11. The sliding member 5 has a surface opposed to the surface on which the magnets 7 and 8 and the magnetic detection element 9 are disposed as a sliding surface 6, and a magnetic medium 1 is transported in contact with the sliding surface 6. The magnet 7 has an NS direction perpendicular to the sliding surface 6 and can generate a magnetic field intensity sufficient to magnetically saturate all magnetic printing parts of a magnetic medium 1 on the sliding surface 6. The magnet 8 is disposed such that the NS direction is perpendicular to the sliding surface 6 and the NS direction is opposed to the magnet 7, and has a magnetic field intensity that allows magnetization reversal of only a part of the magnetic printing part having a small coercivity.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a magnetic identification sensor that performs magnetic detection on a paper-like medium in which a magnetic ink containing magnetic material such as banknotes or a paper-like medium incorporating a magnetic foil band is incorporated, and performs type determination and authenticity determination. The present invention relates to a magnetic identification device.

  Conventionally, in banknote recognition, printed magnetic ink is magnetized by a magnetic field application means such as a magnet in a magnetic sensor, a change in the magnetic field related to the print pattern is detected by a magnetic detection element, and the type is determined from recognition of the magnetic pattern. And authenticity judgment.

  In recent years, new technologies have been incorporated as measures for preventing counterfeiting. Among them, those with a magnetic printing part having a high coercive force Hc have appeared, and a technique for identifying the part has become necessary. It was.

  Until now, in addition to hard magnetic printing with a large residual magnetization Br, there are magnetic media that incorporate a magnetic printing section with a soft magnetism with a very small residual magnetization Br. A method of comparing with a plurality of sensors has been proposed (see Patent Documents 1 and 2).

Japanese Patent No. 5889697 JP 2006-127167 A Special table 2008-517360 gazette

  However, although this method seems to be able to detect a magnetic printing part having a high coercive force, it is necessary to use a plurality of sensors, which is disadvantageous in terms of an increase in size and cost. In another method, there is a description of a method for detecting a medium having different coercive forces of high and low, but it is necessary to prepare magnets at the top and bottom, which complicates the magnetizing method, and is a method for detecting by one magnetic detection element. (See Patent Document 3).

  As described above, there have been many proposals of a magnetic detection method for discriminating the type of a magnetic medium including the level of coercive force. However, it is necessary to compare the outputs of two or more sensors, or there is a magnetization method. There is a problem that it is complicated.

  The present invention has been made in view of such problems. The object of the present invention is to read a magnetic print pattern on a medium and to measure the coercive force contained therein with a simple magnetizing means and one magnetic detection element. It is an object of the present invention to provide a magnetic identification sensor and a magnetic identification device capable of simultaneously performing high / low discrimination.

  In order to solve the above-described problem, an aspect of the present invention is a magnetic identification sensor that magnetizes a medium to be conveyed and identifies a magnetic field strength distribution of the magnetized medium, and includes a magnetic body portion of the medium. A first magnetic field peak that is magnetized in a first direction is generated, and only a part of the magnetic body portion magnetized in the first direction is provided downstream from the first magnetic field peak in the transport direction of the medium. A medium magnetizing unit that generates a second magnetic field peak that is magnetized in a second direction opposite to the first direction, and the medium that is disposed downstream of the medium magnetizing unit in the transport direction of the medium is generated. And a magnetic detection element for detecting a magnetic field intensity distribution.

  In another aspect, the magnetic body portion further includes a high coercive force portion and a low coercive force portion, and the first magnetic field peak has a magnetic field strength equal to or higher than the coercive force of the high coercive force portion, The magnetic field peak is a magnetic field strength that is equal to or greater than the coercive force of the low coercive force portion and smaller than the coercive force of the high coercive force portion.

  In another aspect, the medium magnetizing means further includes first and second magnets, and the first magnet is arranged such that an NS direction is perpendicular to a conveyance direction of the medium, and the first magnet The second magnet is arranged such that the NS direction is opposite to the first NS direction.

  In another aspect, the magnetic field strength of the first magnet is 2 k Oersted (hereinafter abbreviated as Oe) or more, and the magnetic field strength of the second magnet is 0.8 kOe or more and less than 2 kOe. .

  In another aspect, the medium magnetizing means further includes a multipolar magnet having two pairs of magnetic poles whose NS directions are opposite to each other.

  In another aspect, the medium magnetizing means further includes a magnet having a pair of magnetic poles, and the magnet is arranged so that an NS direction is parallel to a transport direction of the medium.

  Another aspect is a magnetic identification device that identifies a magnetization direction of the magnetic body portion based on a magnetic identification sensor and a magnetic field intensity distribution generated by the medium detected by the magnetic identification sensor, and the magnetization And an identification unit for identifying the coercive force of the magnetic body according to the direction.

  According to the present invention, it is possible to simultaneously read a magnetic print pattern of a medium and determine the level of coercivity in the medium with a simple magnetizing means and one magnetic detection element.

(A) is a perspective appearance figure showing the example of composition of the magnetic discernment sensor concerning Embodiment 1 of the present invention, and (b) is the figure showing the example of composition of the fluxgate sensor as an example of a magnetic sensing element. (A) is sectional drawing showing the structural example of the magnetic identification sensor which concerns on Embodiment 1 of this invention, (b) is a mode which showed distribution of the magnetic field Hx of the conveyance direction on the sliding surface of a magnet (C) is a figure which shows the magnetic field strength distribution of the magnetic field component Hx of the X direction of the low coercive force printing part and the high coercive force printing part or the magnetic field component Hz of the Z direction orthogonal to the X direction. It is a figure which shows the magnetization characteristic of the low coercive force printing part 2 and the high coercive force printing part 3 by making saturation magnetization into 100%. It is a figure which shows the structural example of the multipolar magnet which has two pairs of magnetic poles with NS direction opposite. It is a figure which shows the structure of the test medium prepared as a magnetic medium. (A) is a figure which shows the output waveform from the magnetic detection element at the time of using only one magnet as a magnetization means, (b) is the magnetic detection element 9 at the time of using two magnets as a magnetization means. It is a figure which shows the output waveform from. It is a magnetic identification sensor which concerns on Embodiment 1 of this invention, Comprising: It is a figure which shows another structural example from which a conveyance direction becomes both directions. It is a perspective appearance figure showing the example of composition of the magnetic discernment sensor concerning Embodiment 2 of the present invention. (A) is sectional drawing showing the structural example of the magnetic identification sensor which concerns on Embodiment 2 of this invention, (b) is a mode which showed distribution of the magnetic field Hx of the conveyance direction on the sliding surface of a magnet FIG. (A) is a figure which shows the structural example of the magnetic identification sensor which arranged two or more magnets and the magnetic detection elements in the Y direction orthogonal to a conveyance direction, (b) is on a sliding surface with an opposing roller. It is a figure which shows a mode that a magnetic medium is conveyed. It is the schematic of a paper sheet transaction apparatus. It is a figure which shows the structural example of the control unit of a paper sheet transaction apparatus.

  Hereinafter, embodiments of the present invention will be described in detail.

(Embodiment 1)
FIG. 1A is a perspective external view showing a configuration example of a magnetic identification sensor according to Embodiment 1 of the present invention. 2 is a perspective external view showing a positional relationship between a paper-like magnetic medium 1 to be identified, magnets 7 and 8 and a magnetic detection element 9 constituting a sensor body 4. FIG.

  The sensor body 4 includes a sliding member 5, magnets 7 and 8 and a magnetic detection element 9 disposed immediately below the sliding member 5, and is disposed between the conveyance paths 10 and 11. The sliding member 5 has a surface facing the surface on which the magnets 7 and 8 and the magnetic detection element 9 are disposed as a sliding surface 6, and the magnetic medium 1 is conveyed in contact with the sliding surface 6. The sliding member 5 is made of a nonmagnetic metal such as a copper alloy.

  The magnet 7 has a NS direction perpendicular to the sliding surface 6 and can generate a magnetic field intensity sufficient to magnetically saturate all the magnetic printing portions of the magnetic medium 1 on the sliding surface 6. The magnet 8 is arranged so that the NS direction is perpendicular to the sliding surface 6 and the NS direction is opposite to the magnet 7, and a magnetic field that reverses the magnetization of only a part of the magnetic printing part having a small coercive force. Has strength.

  FIG. 1B shows a configuration example of a fluxgate sensor as an example of the magnetic detection element 9. The magnetic detection element 9 is a magnetic detection element that can detect either the magnetic field Hx in the conveyance direction of the magnetic medium 1 or the magnetic field Hz perpendicular to the magnetic field 1 and is, for example, a fluxgate sensor shown in FIG. Can do. On the detection surface 21 of the fluxgate sensor, an elongated magnetic thin film 22 having a high magnetic permeability such as permalloy, amorphous, or microcrystalline structure and a planar coil 23 made of a conductive metal thin film such as copper or aluminum are interposed via an insulating film (not shown). Are stacked and drawn to the electrode 24, respectively. The magnetic field detection direction is the longitudinal direction of the magnetic thin film 22.

  In the magnetic identification sensor according to the first embodiment, when the magnetic medium 1 conveyed from the upstream conveyance path 10 reaches the sensor body 4, the magnet 7 aligns the magnetization direction of the entire magnetic medium 1 and the magnet 8 maintains the magnetization direction. After reversing the magnetization of only a part of the magnetic printing portion having a low magnetic force, the magnetic detection of the magnetic medium 1 is performed by the magnetic detection element 9.

The magnetic medium 1 as a main identification target in the present invention has a plurality of rectangular magnetic printing parts in which ink containing a magnetic material is printed on paper like bills, and the magnetic printing part has a coercive force Hc. A small low coercive force printing unit 2 and a high coercive force printing unit 3 having a large coercive force Hc are included. The low coercive force printing portion 2 can be detected by a magnetic sensor that generates a magnetic field of about 0.8 kOe at the position of the sliding portion as in the prior art, and includes gamma hematite (γ-Fe ₂ O ₃ ) and magnetite (Fe Pigments containing iron oxide such as ₃ O ₄ ) are mainly used. The high coercive force printing unit 3 has a coercive force Hc of over 2 kOe, and magnetic materials such as metal magnetic recording materials used for storage media, epsilon iron oxide (ε-Fe ₂ O ₃ ) and strontium ferrite (SrO · 6Fe ₂ O ₃ ). The body is used.

  In the present invention, in order to identify the magnetic pattern of the magnetic medium 1, it is necessary to change the magnetization direction of the magnetic printing unit according to the coercive force. However, since the magnetization state of each magnetic printing part of the magnetic medium 1 is unknown until magnetism is detected, all the magnetic printing parts regardless of the coercive force are first magnetically saturated, and the low coercive force printing part 2 and the high coercive printing part 2 are detected. The magnetization direction of the magnetic printing unit 3 is aligned. Therefore, the magnet 7 generates a magnetic field intensity sufficiently exceeding the coercive force Hc of the high coercive force printing unit 3 on the sliding surface 6. For example, the magnetization level by the magnet 7 is desirably 80% or more of the saturation magnetization of the high coercive force printing unit 3 as 100.

  On the other hand, the magnet 8 generates a magnetic field intensity that can reverse the magnetization of only the low coercive force printing unit 2 among the magnetic printing units magnetized in the same direction by the magnet 7. That is, the magnet 8 has a magnetic field strength that is greater than or equal to the coercive force Hcb of the low coercive force medium 2 and smaller than the coercive force Hca of the high coercive force medium 3.

  2A to 2C, the relationship between the magnetic fields from the magnets 7 and 8 and the magnetization of the low coercive force printing unit 2 and the high coercive force printing unit 3 will be described in detail. FIG. 2A is a cross-sectional view illustrating a configuration example of the magnetic identification sensor according to the first embodiment of the invention. As shown in FIG. 2A, the magnets 7 and 8 generate Φp and Φm magnetic fluxes from the magnetic poles on the sliding surface 6 side, and the magnetic medium 1 passing on the sliding surface 6 receives the magnetic fluxes. . Since the magnetic printing portion of the magnetic medium 1 is easily magnetized in the in-plane direction of the magnetic medium 1, the magnetization level depends on the magnetic field Hx of the transport direction component.

  FIG. 2B shows the distribution of the magnetic field Hx in the transport direction on the sliding surface 6 of the magnets 7 and 8. The magnetic printing part that has passed over the magnet 7 is magnetized by a magnetic field peak Ha having a large peak on the exit side (upstream side in the transport direction). As described above, the magnetic field peak Ha on the sliding surface 6 of the magnet 7 is set to be equal to or greater than the coercive force Hca of the high coercive force printing unit 3 in order to align the magnetization directions of all the magnetic printing units.

  FIG. 3 shows the magnetization characteristics of the low coercive force printing unit 2 and the high coercive force printing unit 3 with a saturation magnetization of 100%. Assuming that 80% is the susceptibility J in FIG. 3, the magnetic field peak Ha of the magnet 7 is desirably about 20% larger than the coercive force Hca of the high coercive force printing unit 3. The coercive force Hca of the high coercive force printing unit 3 is often used and is often 2 kOe, and the magnetic force of the magnet 7 is preferably at least 2.2 kOe, more preferably about 2.4 kOe to 3 kOe. It is desirable to have

  The magnetic printing section that has passed over the magnet 7 and further passed over the magnet 8 has a magnetization detected by the magnetic detection element 9 by a magnetic field peak Hb on the exit side (upstream side in the transport direction) as shown in FIG. The state is confirmed. As described above, since the magnet 8 reverses the magnetization of only the low coercive force printing unit 2, the magnetic field peak Hb on the sliding surface 6 of the magnet 8 is higher than the coercive force Hcb of the low coercive force printing unit 2. The magnetic force is adjusted to have a magnetic field strength smaller than the coercive force Hca of the printing unit 3. The coercive force Hcb of the low coercive force printing unit 2 is sufficiently magnetized as long as 0.8 kOe is used in existing banknotes. Therefore, it is practical to set the magnetic force of the magnet 8 to be approximately 0.8 kOe or more and smaller than 2 kOe. It seems to be the target.

  To summarize, in the present invention, the relationship between the magnetic field strength on the sliding surface 6 by the magnets 7 and 8 and the coercive force of the magnetic printing portion of the magnetic medium 1 is represented by the order of the magnetic field strength in absolute value expression: The following conditions are met.

| Ha |> | Hca |> | Hb |> | Hcb | (1)
Assuming that the coercive force Hca of the high coercive force printing unit 3 is about 2 kOe, the magnetic field peak Ha on the sliding surface 6 by the magnet 7 is set to 2 kOe or more, and the magnetic field peak Hb on the sliding surface 6 of the magnet 8 is It is preferably 0.8 kOe or more and less than 2 kOe.

  The magnetic field peaks Ha and Hb can be adjusted by the magnitude of the magnetic force of the magnets 7 and 8, the magnitude of the magnetic pole surface, the distance from the sliding surface 6, the distance between the magnets, and the like.

  As shown in FIG. 2A, the low coercive force printing unit 2 and the high coercive force printing unit 3 that have passed over the magnets 7 and 8 having such a magnetic field strength are magnetized so that the NS direction is relatively reversed. Is done. The magnetic detection element 9 uses the magnetic flux emitted from the low coercive force printing unit 2 and the high coercive force printing unit 3 as a magnetic field component Hx in the X direction or a magnetic field component Hz in the Z direction perpendicular to the X direction (or a magnetic field component Hy in the Y direction). The distribution of the magnetic field intensity is shown in FIG. 2 (c).

  The magnetic field component Hx can be detected as a quantitative waveform, and if the output of the magnetic detection element 9 is DC amplified, the detection sensitivity can be increased. Further, since the attenuation is gentle even if the distance between the magnetic detection element 9 and the magnetic medium 1 is increased, detection is possible even when the distance from the sliding surface 6 is close to 1 mm. On the other hand, the magnetic field component Hz becomes a differential waveform of the magnetic field component Hx, and a component having a high frequency increases. Therefore, the resolution of the magnetic detection element 9 can be improved by bringing the tip as close as possible to the sliding surface 6. The magnetic medium 1 is preferably conveyed so as to be in contact with the sliding surface 6 as much as possible, but there is no problem if it floats about 0.2 to 0.3 mm.

  As an example of the magnetic detection element 9, a fluxgate (FG) sensor is shown in FIG. 1 (b). However, the magnetic detection element 9 is not limited to a specific element, and a magnetoresistive element (SMR, AMR, GMR). Or a magnetic impedance element (MI). Further, the magnetic detection element 9 may be arranged so as to detect either the X direction or the Z direction (direction perpendicular to the X direction) of the magnetic field according to the characteristics of the various elements. Whichever magnetic detection element is used, if the magnetic medium 1 is magnetized using two magnets satisfying the condition shown in the above formula (1), whether it is a differential waveform or a quantitative waveform, The level of coercive force can be identified from the output waveform of one magnetic detection element showing the magnetic field distribution reflecting the difference in polarity, that is, the difference in NS direction. What is important in the present invention is how to magnetize in accordance with the coercive force of the magnetic medium 1, and there are no restrictions on the type and detection direction of the magnetic detection element 9.

  Next, the result of verifying the waveform actually detected using the magnetic identification sensor having the following configuration will be described.

FIG. 5 shows the configuration of a test medium prepared as the magnetic medium 1. The magnetic medium 1 includes a rectangular paper having a thickness of 0.1 mm, a low coercive force printing portion 2 having a coercive force Hc = 0.6 kOe containing a magnetic material of gamma hematite (γ-Fe ₂ O ₃ ), a metal A high coercive force printing portion 3 having a coercive force Hc = 2 kOe including a magnetic material of a magnetic recording material was printed, and each rectangular pattern size was set to 0.75 × 1.5 mm.

  The magnet 7 is an Nd—Fe—B magnet having a residual magnetic flux density of 1.3 T, the magnetic pole size is 10 × 0.8 mm, the NS interval is 1.6 mm, and the magnetic field peak Ha shown in FIG. 2B is 2.8 kOe. It became. The magnet 8 was made of the same material as the magnet 7, and the magnetic pole size was reduced to 10 × 0.4 mm, the NS interval was the same 1.6 mm, the magnetic force was reduced, and the NS direction was reversed and the magnet 8 was installed downstream. The magnetic field peak Hb was 1.35 kOe. If the widths of the magnetic poles of these magnets 7 and 8 are set as wide as 10 mm, the medium can be surely magnetized and a stable magnetic field can be obtained even if the target magnetic detection unit is displaced.

  As the magnetic detection element 9, a flux gate sensor having a detection width of 1.6 mm for detecting a magnetic field component Hz in a direction orthogonal to the transport direction (X direction) is used, and the magnetic field distribution is captured with a differential waveform.

  The sensor body 4 having such a configuration was scanned from the magnet 7 side along the line indicated by the arrow with respect to the magnetic medium 1 shown in FIG.

  FIG. 6A shows an output waveform from the magnetic detection element 9 when only the magnet 7 is used as the magnetization means, and FIG. 6B shows magnetic detection when the magnets 7 and 8 are used as the magnetization means. The output waveform from the element 9 is shown. When only the magnet 7 is magnetized, the rising edges of the waveforms corresponding to the low coercive force printing unit 2 and the high coercive force printing unit 3 are both downward, indicating that the polarities are aligned (FIG. 6A). ). On the other hand, when the magnet 8 is added to the magnet 7 as the magnetizing means, only the rising edge of the waveform corresponding to the low coercive force printing unit 2 is upward, and only the polarity of the low coercive force printing unit 2 is reversed. (FIG. 6B). As described above, in the present invention, for example, in a forged banknote, when a low coercive force magnetic material is used at a position where the high coercive force printing unit 3 should be, the output waveform detected by one magnetic detection element 9 is used. Authentication can be easily determined from the phase.

  In addition, since the present invention can identify not only the presence / absence of phase inversion but also the amplitude voltage of each waveform at the same time, a function for easily determining the coercive force is added while retaining the conventional amplitude voltage pattern identification function. it can.

  In the first embodiment, the two magnets 7 and 8 are used as the magnetizing means as described above. However, as a modification of the magnetizing means, the magnets 7 and 8 are integrated and a magnetizing jig is used as shown in FIG. A multipolar magnet 12 having two pairs of magnetic poles whose NS directions are reversed can be used. In this case, the magnetic field peaks Ha and Hb on the sliding surface 6 can be adjusted by adjusting the ratio Wa: Wb of the magnetic pole surfaces.

  FIG. 7 shows a configuration example of a magnetic identification sensor in which the transport direction is both directions. The magnets 7 and 8 and the magnets 7 'and 8' may be arranged on both sides so as to sandwich the magnetic detection element 9. The polarity of the magnet is only required to be reversed between the magnet 7 and the magnet 8 and between the magnet 7 'and the magnet 8', and the magnet polarity on the entry side (outside) is limited to the N pole. is not.

(Embodiment 2)
FIG. 8 is a perspective external view showing a configuration example of a magnetic identification sensor according to Embodiment 2 of the present invention. In the first embodiment, two magnets 7 and 8 or a multipolar magnet 12 having two pairs of magnetic poles are used to arrange their NS directions perpendicular to the sliding surface 6. Only one magnet 13 having a pair of magnetic poles is used, and its NS direction is arranged parallel to the sliding surface 6. The magnet 13 is a weak magnetic field in which the magnetization direction of the magnetic medium 1 is aligned with a strong magnetic field generated in a portion between the magnetic poles, and the magnetic field direction generated in the vicinity of the magnetic pole on the exit side (downstream in the transport direction) is reversed with respect to the magnetic poles. Only the low coercive force printing unit 2 is adjusted to reverse the magnetization.

  FIG. 9A is a cross-sectional view illustrating a configuration example of the magnetic identification sensor according to the second embodiment of the present invention. FIG. 9B shows the distribution of the magnetic field Hx in the transport direction on the sliding surface 6 of the magnet 13. As shown in FIGS. 9A and 9B, the magnetic field component Hx in the X direction between the NS poles of the magnet 13 becomes maximum at the center, and the magnetic field peak Ha is determined by the maximum magnetic field strength here. In addition, in the vicinity of the magnetic pole on the exit side, here the S pole, a magnetic flux Φm in the direction opposite to the magnetic flux Φp is generated, and the magnetic field peak Hb is determined by the magnetic flux Φm orthogonal to the S pole surface. The relationship between the magnitudes of the magnetic field peaks Ha and Hb and the coercive forces Hcb and Hca of the low coercive force printing unit 2 and the high coercive force printing unit 3 is the same as the equation (1) in the first embodiment.

  The magnetic field peaks Ha and Hb can be adjusted by adjusting the NS interval L of the magnet 13 and the area of the magnetic poles, and the magnitude and balance of the magnetic field peaks Ha and Hb. Further, as shown in FIG. 9A, the NS direction of the magnet 13 is rotated around an axis parallel to the sliding surface 6 (θ direction) to change the distance between the center of the magnet 13 and the magnetic pole, It is also possible to adjust the magnitudes of the magnetic field peaks Ha and Hb and their balance by moving them in the Zd direction perpendicular to the sliding surface 6.

  In the first and second embodiments, the configuration of a single magnetic identification sensor is described. However, it is a matter of course that a plurality of magnets 13 and magnetic detection elements 9 are arranged in the Y direction orthogonal to the transport direction. It can respond. FIG. 10A shows a configuration example of a magnetic identification sensor in which a plurality of magnets 13 and magnetic detection elements 9 are arranged in the Y direction orthogonal to the transport direction. What is necessary is just to set the width | variety of the sensor main body 4 and the sliding member 5 according to the width | variety of magnetic media, such as a banknote to identify. The magnets 13 can eliminate detection omissions by arranging them without gaps so that they can be magnetized wherever magnetic information is present. The configuration of the present invention is easy to extend in the direction perpendicular to the transport direction and has a high degree of freedom.

  The magnetic detection element 9 is also placed in parallel with the magnet 13, but the track as a detection unit is divided into necessary units to function as a multi-channel sensor. An output signal from the magnetic detection element 9 is converted into a serial output by a circuit board prepared on the side opposite to the sliding surface 6 and transmitted to the control unit.

  The bill as a magnetic medium is conveyed so as not to float on the sliding surface 6 by the opposing roller 30 as shown in FIG. 10B, and the magnetic medium is magnetized by the magnetic field from the magnet or from the magnetized magnetic medium. To enable stable detection of magnetic field strength. In addition to the facing roller 30, a urethane sponge may be used to restrict the gap, or a brush may be used to suppress the gap by applying a little pressure.

  In FIG. 11, the schematic of a paper sheet transaction apparatus (banknote transaction apparatus) is shown. The magnetic identification sensor of the present invention is assumed to be incorporated into such a paper sheet transaction apparatus, and a specific example of the paper sheet transaction apparatus is an automatic cash machine installed in a financial institution such as a bank or a convenience store. There is a transaction device (ATM).

  In the paper sheet transaction apparatus 100, a touch panel unit 104 that receives a customer's operation is installed on the surface of the apparatus as an input unit, and a banknote is inserted from a banknote insertion slot 103 nearby.

  A bill inserted from the bill insertion slot 103 is transported on a transport path 105 by a roller 106, and first, the discrimination unit 101 performs denomination determination and authenticity determination. The discrimination unit 101 is a mechanical unit on which a plurality of sensors such as the optical sensor 31 and the magnetic identification sensor 4 are mounted. Control of the mechanism and sensor and reception of the signal are performed by the control unit 102, and after the denomination and authenticity determination, sorting is performed downstream of the conveyance path 105, and each denomination is put into the respective denomination storages 108A to 108D. The counterfeit ticket is returned to the original by switchback or is put into the reject storage box 107.

  FIG. 12 shows a configuration example of the control unit of the paper sheet transaction apparatus. The CPU 201 controls the discrimination unit 101 using programs such as discrimination device control, denomination determination control, authenticity determination control, and threshold setting in the ROM 202. Data of various sensors is stored in the RAM 203, and a determination is made in light of each threshold value. The output waveform output from the magnetic identification sensor of the present invention is also read into the authenticity determination program, and the phase is inverted based on the position information of the high coercive force printing unit and the low coercive force printing unit recorded in advance for each denomination. It is determined whether or not the corresponding position corresponds to the recorded information. The CPU 201 can exchange data with the host computer 300 via the communication unit 204.

  The identification of the type of magnetic material in a conventional magnetic medium requires the use of a complicated magnet configuration and two or more magnetic detection elements, making it difficult to combine them into a single sensor, resulting in space-saving and cost issues. It was big.

  As described above, the present invention is specially designed to detect a magnetic material having a high coercive force, and is designed so that the magnetization direction of the magnetic printing part is reversed according to the coercive force for the need to increase the identification accuracy. By magnetizing the magnetic medium with the magnetizing means for generating the magnetic field intensity distribution, the high coercive force printing portion can be detected easily and with high accuracy from the magnetic field intensity distribution of the magnetic medium detected by one magnetic detection element. The present invention can provide a conventional magnetic identification sensor with a function of improving identification accuracy at low cost.

DESCRIPTION OF SYMBOLS 1 Magnetic medium 2 Low coercive force printing part 3 High coercive force printing part 4 Sensor main body 5 Sliding member 6 Sliding surface 7, 8, 7 ', 8', 12, 13 Magnet 9 Magnetic detection element 10, 11 Conveyance path 30 Opposite Roller 31 Optical sensor 100 Paper sheet transaction apparatus 101 Identification unit 102 Control unit 103 Banknote slot 104 Touch panel unit 105 Transport path 106 Roller 107 Reject storage box 108A-108D Money storage box

Claims (7)

A magnetic identification sensor that magnetizes a medium to be conveyed and identifies a magnetic field strength distribution of the magnetized medium,
A first magnetic field peak that magnetizes the magnetic body portion of the medium in a first direction is generated, and the magnetism magnetized in the first direction downstream from the first magnetic field peak in the transport direction of the medium. Medium magnetization means for generating a second magnetic field peak for magnetizing only a part of the body part in a second direction opposite to the first direction;
A magnetic detection element that is disposed downstream of the medium magnetization means in the conveyance direction of the medium and detects a magnetic field intensity distribution generated by the medium;
A magnetic identification sensor comprising: The magnetic body portion includes a high coercive force portion and a low coercive force portion,
The first magnetic field peak is a magnetic field strength equal to or higher than the coercive force of the high coercive force portion,
2. The magnetic identification sensor according to claim 1, wherein the second magnetic field peak has a magnetic field strength that is equal to or greater than a coercive force of the low coercive force portion and smaller than a coercive force of the high coercive force portion. The medium magnetization means includes first and second magnets,
The first magnet is arranged so that an NS direction is perpendicular to a conveyance direction of the medium,
3. The magnetic identification sensor according to claim 1, wherein the second magnet is arranged such that an NS direction is opposite to the first NS direction. 4.   The magnetic field strength according to any one of claims 1 to 3, wherein the magnetic field strength of the first magnet is 2 kOe or more, and the magnetic field strength of the second magnet is 0.8 kOe or more and less than 2 kOe. Identification sensor.   The magnetic identification sensor according to claim 1, wherein the medium magnetization unit includes a multipolar magnet having two pairs of magnetic poles whose NS directions are opposite to each other. The medium magnetization means includes a magnet having a pair of magnetic poles,
The magnetic identification sensor according to claim 1, wherein the magnet is arranged so that an NS direction is parallel to a conveyance direction of the medium. A magnetic identification sensor according to any one of claims 1 to 6,
An identification unit that identifies a magnetization direction of the magnetic body unit based on a magnetic field intensity distribution generated by the medium detected by the magnetic identification sensor, and identifies a coercive force of the magnetic body unit according to the magnetization direction;
A magnetic identification device comprising:

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