WO1999044176A1

WO1999044176A1 - Method and device for checking coin for forgery

Info

Publication number: WO1999044176A1
Application number: PCT/JP1999/000881
Authority: WO
Inventors: Yonezo Furuya
Original assignee: Kabushiki Kaisha Nippon Conlux
Priority date: 1998-02-26
Filing date: 1999-02-25
Publication date: 1999-09-02
Also published as: CA2288297C; CA2288297A1; KR100562857B1; JPH11250305A; AU729021B2; JP3660496B2; EP0978807A4; MY123288A; EP0978807A1; KR20000076308A; AU2549499A

Abstract

A method and device for checking a coin for forgery by means of a difference in an uneven pattern on a coin surface, wherein an exciting coil is disposed in the vicinity of a passage wall on one side of a coin passage inclined at a preset angle so that the two magnetic poles of the exciting coil face the coin passage, and two receiving coils having approximately identical characteristics are disposed in the vicinity of the same passage wall for electromagnetic coupling with the exciting coil. The exciting coil is excited at a preset frequency to detect by the receiving coil an effect on a diamagnetic field by an eddy current produced on a coin surface. A different uneven pattern on the coin surface generates a different diamagnetic field strength to enable us to check the coin for forgery. The device, simple in construction and inexpensive to construct, can discriminate a coin of approximately the same material, shape and thickness according to a difference in its surface pattern.

Description

Specification

Method and apparatus for determining authenticity of coin

Technical field

The present invention relates to a method and an apparatus for judging the authenticity of coins by identifying coins, and particularly to the authenticity of coins used in vending machines, game machines and the like. It relates to the method and the device for discrimination.

Background technology

In recent years, electronic identification devices that use induction coils have become the mainstream of coin identification devices. This type of coin identification device generally uses the fall of the coin due to its own weight, so that a passage for guiding the coin inserted from the coin inlet is provided. It is provided. A plurality of sets of induction coils are arranged in this passage, and each set of induction coils is provided with an electromagnetic field that is excited by a different frequency.

The inspection of a coin is based on the fact that when a coin passes through an electromagnetic field, the amount of electrical change (frequency change, voltage change, phase change) obtained by the interaction between the electromagnetic field and the coin. Is detected to check the authenticity of the coin.

The coin inspection apparatus in the prior art is disclosed in US Pat. No. 3,870,13, since the characteristics of coin are often expressed in terms of frequency-dependent parameters. As No. 7 shows, it has been used as a technique for inspecting the material, outer diameter, thickness, etc. of coins by using multiple frequencies.

In recent years, coins from other countries have become Increasing numbers of cases have been identified, such as fraud by those who mistakenly or wrongfully make those coins. Some of the coins in each country are similar in material, outer diameter, thickness, etc. For example, 5 CENT coins in the United States and ヽ. The 5 CENT ESIMOS coin of Nama is a representative example. Such a coin has almost the same material, outer diameter, and thickness only with a different surface design (irregular pattern). In the configuration of the induction coil as in the prior art, a minute change cannot be detected only by using a plurality of frequencies for the uneven pattern on the surface of such a coil, and as a result, as described above. The coin could not be determined.

In addition, the 500 yen coin of Japan and the 500 won coin of Korea have almost the same material and outer diameter, and the 500 won coin is slightly thicker. For this reason, when this 500 won coin is processed and used as a 500 yen coin, the authenticity of the coin is checked with the thickness, outer shape, and material of the conventional coin. With this method, it was difficult to distinguish between the processed 500 won coin and the 500 yen coin.

Further, in the prior art, an optical method such as image processing has been attempted as a means for discriminating coins as described above. However, the optical device has a problem that dust or the like adheres to the device and impairs the determination of the authenticity of the coin.The problem is that the device becomes larger or more complicated, and as a result, more expensive. was there.

Disclosure of the invention

An object of the present invention is to provide a method and an apparatus for determining the authenticity of coins that can identify coins with high accuracy. A method of determining the authenticity of a coin according to the present invention is a step of arranging an exciting coil and a receiving coil near a coin path so as to be electromagnetically coupled to each other. And a frequency at which the effect of the demagnetizing field due to the eddy current generated on the surface of the coin when the coil passes through the electromagnetic field is detected by the receiving coil. A step of exciting the exciting coil to generate an electromagnetic field, and detecting the electromagnetic field affected by the demagnetizing field by the receiving coil as an electromotive force signal; and And a step of identifying a coin based on the electromotive force signal detected by the coil.

Because the surface of the coil passing through the coil path and the receiving coil should be close to each other, the coil path in which the exciting coil and the receiving coil are disposed is Form a coin passage so that the coin leans to one side. Further, depending on the material, the penetration of the electromagnetic field into the coin differs depending on the excitation frequency. From this force, the excitation frequency at which the difference in unevenness on the surface of the coin often appears as the difference in the signal from the receiving coil according to the material of the coin to be detected and identified. There is. Therefore, the frequency for exciting the exciting coil is selected and set according to the material of the coin to be identified.

More specifically, an excitation coil disposed near one side of the coin passage so that the magnetic poles face the coin passage inclined at a predetermined angle, and an excitation coil and an electromagnetic coil disposed in the vicinity of one side of the coin passage. The two receiving coils, which have similar characteristics and are arranged near the coin path so that they are coupled to each other, and the exciting coil is excited at a predetermined frequency to generate an electromagnetic field. Exciting means for generating, plunger circuit means including a receiving coil, differential amplifying means connected to the plunger means, and detecting means connected to the differential amplifying means. A signal which is connected to the detection means and obtained when the coin passes through the electromagnetic field is compared with a feature of a predetermined denomination stored in advance, and the signal has a predetermined tolerance for the feature. The authenticity of the coin is determined by an identification unit that determines that the coin is true when the coin is within the range.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1a is a front view showing a configuration of a detection coil for detecting a concavo-convex pattern on a coin surface according to the first embodiment of the present invention, FIG.

FIG. 2 is a block diagram showing a circuit configuration according to the embodiment of the present invention.

FIG. 3 is a specific diagram of the circuit in the embodiment,

FIG. 4 is a front view showing an apparatus for inspecting the authenticity of coins according to an embodiment of the present invention,

FIG. 5 a is a front view detailing the configuration of the coil in the embodiment of the present invention, FIG.

FIG. 6 is a characteristic diagram showing characteristics of a representative coin in the embodiment of the present invention.

FIG. 7 is a comparison diagram showing the specifications of a representative coin in the embodiment of the present invention.

FIG. 8 is a flowchart showing the operation according to the embodiment of the present invention. FIG. 9A is a front view showing a configuration of a detection coil for detecting an uneven pattern according to the second embodiment of the present invention, FIG. 9B is a sectional view thereof,

FIG. 10a is a front view showing a configuration of a detection coil for detecting an uneven pattern according to the third embodiment of the present invention, and FIG. 10b is a cross-sectional view thereof.

FIG. 11 a is a front view showing a configuration of a detection coil for detecting an uneven pattern according to a fourth embodiment of the present invention, FIG.

FIG. 12 is an explanatory diagram showing an example in which the portion of the coin passage wall where the receiving coil is arranged in each embodiment of the present invention is made of a material having high magnetic permeability.

BEST MODE FOR CARRYING OUT THE INVENTION

An embodiment of the present invention will be described with reference to FIG. 1A, FIG. 1B, and FIG.

As shown in Fig. 1a and Fig. 1b, the detector for identifying coin 3 is composed of one excitation coil 1 and two reception coin coils 2a and 2b. The rail is provided so as to be in contact with the passage wall 7 a on one side of the coin passage 6. The coin passage 6 is inclined at a predetermined angle in order to guide and drop the coin 3, and includes a coin rail 4 disposed at the bottom and a pair of passage walls 7 a and 7 b. It is configured. As shown in Fig. 1b, the passage walls 7a and 7b are arranged to be inclined with respect to the vertical direction so that the coin 3 falls down to the side of the passage wall 7a. It has been done. Also, the surface of the coin rail 4 for applying and guiding the coin is The configuration is such that the passing coin 3 is inclined in the direction of inclination of the passage walls 7a and 7b such that the coin 3 passing therethrough is inclined toward the passage wall 7a.

Each of the two receiving coils 2a and 2b is composed of a drum type core 43 and a coil 44 wound around the core 43 as shown in FIG. 5b. . As shown in FIG. 1a, the receiving coils 2a and 2b are connected to the line 5a above the coil coil 4 and connecting the centers of the coils 2a and 2b. Are arranged at a predetermined interval so as to be substantially parallel to the rule 4.

As shown in FIG. 5A, the excitation coil 1 is composed of a U-shaped core 40 made of a magnetic material and a coil 41 wound around the core 40. As shown in Fig. La, the exciting coil 1 is located above the receiving coils 2a and 2b, the center C3 of the core 40 is located at the center C1 of the receiving coil 2a and the receiving coil. Line 5c that is perpendicular to the line 5a connecting the center C2 of the line 2 and that passes through the midpoint M of the line segment C1C2, and that connects the centers of both pole faces 40a. b is arranged so that it is substantially parallel to coil rail 4. Further, as shown in FIG. Lb, the pole face 40a of the core 40 is arranged so as to be parallel to the plane of the coin 3 passing therethrough. Note that 42 in FIG. 5a and 45 in FIG. 5b indicate lead lines.

The excitation coil 1 and the receiving coils 2a and 2b arranged as described above are electromagnetically coupled by an electromagnetic field generated by the excitation of the excitation coil 1.

In FIG. 2, the oscillation circuit 11 is, for example, an MPU (My A square wave signal of a specified frequency generated by a cross-processor (unit) or the like is output to the output terminal. The output of the oscillation circuit 11 is connected to the excitation drive circuit 12, and the output of the excitation drive circuit 12 is connected to the excitation coil 1 to excite the excitation coil 1. As a result, the exciting coil 1 generates an electromagnetic field around the exciting coil 1 in response to the output signal of the exciting drive circuit 12.

On the other hand, an electromotive force corresponding to the intensity of the electromagnetic field generated by the exciting coil 1 is generated in the two receiving coils 2a and 2b. As described above, it is desirable that the excitation coil 1 and the receiving coils 2a and 2b be arranged close to the surface of the coin 3 and inspected.

When the coin 3 acts in the electromagnetic field, an eddy current is generated near the surface of the coin 3 which is excited by the excitation coil 1, and the action frequency of the eddy current increases. As a result, a remarkable demagnetizing field is generated near the outer periphery of the coin by the skin effect. The demagnetizing current generated near the outer peripheral surface of the coil due to the above phenomenon interacts with the receiving coils 2a and 2b with a slight change in the shape characteristic of the coil surface. . In the receiving coils 2a and 2b, an electromotive force corresponding to the change in the demagnetizing current caused by the change in the shape characteristic of the coil 3 is generated. Hereinafter, a signal generated by this electromotive force is referred to as a “detection signal”.

Further, since the magnetic pole of the exciting coil 1 is arranged near the receiving coils 2a and 2b, the electromagnetic field generated from the magnetic pole acts on the coin 3 The change in the induced demagnetizing current Can be captured in the immediate vicinity.

The demagnetizing current due to the skin effect appears remarkably near the outer periphery of the coin, but when the irregularities on the surface of the coin are conspicuous, the change is detected without being limited to the vicinity of the outer periphery of the coin. Can be issued. The detection signals of the reception coils 2a and 2b are converted into an AC voltage signal corresponding to the detection signals by a bridge circuit 13 configured to include the reception coils 2a and 2b. Is generated and output to the differential amplifier 14. The differential amplifier 14 amplifies the AC voltage signal generated by the bridge circuit 13 and outputs it to the detection circuit 15. The detection circuit 15 receives the AC voltage signal amplified by the differential amplifier 14 and outputs a DC voltage signal corresponding to the detection signal to the discrimination circuit 16. The discriminating circuit 16 receives the AD converter 17 DC voltage signal therein, converts it into a digital signal of a corresponding voltage, and outputs the digital signal to the signal inspection circuit 18 inside the discriminating circuit 16. The signal inspection circuit 18 inspects whether or not the coin 3 has a predetermined characteristic, and outputs the result of the inspection to the output terminal 19. The output of the signal inspection circuit 18 is used to drive a distribution solenoid (to be described later) such as a recorder / counter (not shown).

FIG. 3 is a detailed diagram specifically showing the block circuit of FIG. Fig. 4 is a front view showing a coin inspection device using a detection coil for detecting this uneven pattern. Fig. 5a is a front view detailing the configuration of the coil, and Fig. 5b is a sectional view thereof. In FIG. 3, the circuit configuration is described in detail with reference to the block diagram of FIG. 2.The oscillator circuit 11 is connected by dividing the internal reference clock using the MPU 20. It is configured using the divided frequency means. The excitation coil 1 is connected in parallel with the capacitor C1 so that resonance occurs near a predetermined frequency set by the oscillation circuit 11 to form an LC parallel resonance circuit. .

The excitation drive circuit 12 approximates the square wave output from the oscillation circuit 11 to a triangular wave by connecting the transistor TR1 and resistors R3 and R4 connected so as to perform the switching operation. Connected to an integrating coil consisting of a resistor R5, a canister C4, and a resistor R6 to make the waveform change, and to an exciting coil 1 forming an LC parallel resonance circuit. It is composed of a drive circuit consisting of a transistor TR2 and a resistor R7.

The bridge circuit 13 includes a capacitor C3 connected in parallel with the reception coil 2a, a capacitor C3 connected in parallel with the reception coil 2b, and a capacitor C3 connected in parallel with the reception coil 2b. And resistors R 1 and R 2.

The differential amplifier 14 includes capacitors C5 and C6, which are connected to the output of the bridge circuit 13 so as to couple in an AC manner, and an operational amplifier A1. And a resistor R8, RIO and R9, R11 connected to determine the gain of the operational amplifier.

The detection circuit 15 is a diode connected to the coupling capacitor C 7 connected to the output of the differential amplifier 14. It is composed of a rectifying circuit (voltage doubler rectifying circuit) of Dl and the diode D2, and an integrating circuit composed of the resistor R12 and the capacitor C8.

The AD converter 17 and the signal inspection circuit 18 of the discriminating circuit 16 are configured using an MPU 20 (microprocessor 'unit).

The oscillation circuit 11 outputs a square wave signal of a set predetermined frequency, and the frequency is controlled by the electromagnetic field in order to detect the difference in the irregularities of the coin 3 with good sensitivity. It is desirable that the frequency be such that it penetrates into the surface of the uneven pattern of the pin, does not penetrate to the center, and the effect of the demagnetizing field due to the eddy current appears remarkably. This frequency varies depending on the material of the coin to be discriminated.

When identifying CENTESIMOS coins, the material of these coins is white copper, and when the material of the coin is white copper, the excitation frequency of excitation coil 1 is 70 K (Hz) to 90 K ( The frequency of Hz) is desirable, and in the experiments according to the present invention described later, the frequency was set to 90 K (Hz).

The selection of the frequency for exciting this exciting coil 1 is determined by the material of the target coin.For a coil with the same outer shape but a different thickness, the exciting frequency is changed sequentially. The voltage detected by the receiving coils 2a and 2b is measured, and the frequency at which the change in the detected voltage is large is determined by the change in the thickness of the coil. This frequency is used as the excitation frequency.

For example, in the case of white copper, the excitation frequency is 70 K (H From experiments, it was found that the detected voltage varied the largest in the range of z) to 90 K (Hz) with the change in thickness. At frequencies higher or lower than these 70 K (Hz) to 90 K (Hz), the change in the detection voltage with respect to the change in the thickness of the coil becomes gradually smaller as the distance from the frequency band increases. In other words, in order to discriminate coins based on the difference in thickness, that is, the difference in the unevenness pattern on the surface of the coin, in the case of white copper coins, the excitation of 70 K (Hz) to 90 K (Hz) described above is used. The frequency is suitable.

Also, for example, when the material of the target coin is brass, the excitation frequency of about 7 K (Hz) to LOK (Hz) depends on the change in the thickness of the coin. Output voltage change is large. Therefore, in order to identify the coins made of brass by the uneven pattern on the surface, it is possible to efficiently identify the coins by using an excitation frequency of 7 K (Hz) to 10 K (Hz).

The excitation drive circuit 12 receives the square wave signal output from the oscillation circuit 11 and integrates the square wave by an integration circuit including a resistor R5, a capacitor C4, and a resistor R6. The excitation coil 1 is converted to a waveform approximating a triangular wave, and the excitation coil 1 is driven by the approximate triangular wave signal. The LC resonance circuit including the excitation coil 1 and the capacitor C1 resonates at the frequency, and both ends of the excitation coil 1 are driven with a sine waveform as a result.

The bridge circuit 13 having the above-described configuration constitutes an AC bridge circuit, and is constituted by an impedance comprising a reception coil 2a and a canister C2 connected in parallel. Zl The impedance of the signal coil 2b and the capacitor C3 connected in parallel is Z2, and the impedance of the resistor R1 is Z3 and the impedance of the resistor R2. Letting be Z 4, the condition under which the AC bridge is in an equilibrium state is

Ζ 1 · Ζ 4 = Ζ 2 · Ζ 3

It becomes.

Here, as shown in FIG. 3, the output of the bridge circuit 13 is connected to both the connection point between the receiving coils 2a and 2b and the connection point between the resistors R1 and R2. Since the signal appears between the points, the voltage across the receiving coil 2a is VI, the current flowing through the impedance Z1 is i1, and the voltage across the receiving coil 2b is Assuming that the current flowing through V 2 and impedance Z 2 is i 2, the voltage V def of the signal appearing between the two connection points is as follows (provided that the impedance Z of the resistor R 1 is equal to: 3 and the impedance Z 4 of the resistor R 2 are assumed to be equal).

V 1 = Z 1i 1

V 2 = Z 2 ■ i 2

V def = V 1-V 2

V def = Z 1i1-Z2i2

In this embodiment, the resonance frequency of the LC resonance circuit by the reception coil 2a and the canopy capacitor C2, and the LC resonance circuit by the reception coil 2b and the capacitor C3 And the impedances Z1 and Z2 are substantially equal to each other so that the resonance frequency of the oscillation circuit 11 is substantially equal to the oscillation frequency output by the oscillation circuit 11. The voltage of the signal that appears between the connection points is the current The voltage signal is given by the difference between i 1 and i 2. The differential amplifier 14 receives an AC voltage signal from the bridge circuit 13, amplifies the signal into a desired AC voltage signal, and outputs the signal to the detection circuit 15.

The detection circuit 15 receives the AC voltage signal output from the differential amplifier 14, performs detection rectification by the diode D 1, and outputs a resistor R 12 and a capacitor. The output is converted to a DC voltage signal corresponding to the output of the bridge circuit 13 by an integration circuit constituted by the capacitor C8.

The A / D converter 17 is realized by using, for example, a successive approximation conversion type A / D converter with a resolution of 8 bits built in the MPU 20. The AD converter 17 receives the analog DC voltage signal output from the detection circuit 15, performs sampling at predetermined intervals, and corresponds to the output of the bridge circuit 13. The signal is converted to a digital signal and the digital signal sequence is output to the signal test circuit 18.

The signal inspection circuit 18 inputs the digital signal sequence on the amplitude axis output from the AD converter 17, temporarily stores the digital signal sequence in a memory such as a RAM, and stores the digital data in the RAM temporarily. The statistical value of the signal sequence and the data sequence of the denomination previously stored and held in the memory 21 is obtained, and the statistical value is stored in the memory 21 in advance as a predetermined value. Compares with, checks whether it has the specified characteristics, and outputs the result of the check to output terminal 19.

As a specific method for obtaining the statistical value, a correlation coefficient is calculated. The following equation can be used

In the above equation (1), N is the number of samplings, the variable Xi is the value of the digital signal sequence obtained by measuring the test coin with the sampling value, and the variable Yi is the receiving value. It is a statistical value obtained by sampling the available denominations in advance using the apparatus of the present invention. X a and Y a are the respective average values.

If the processing speed of the MPU is taken into consideration, the sampling value Y i and the average value Y a of the acceptable denominations in the cross-product sum of deviation of the numerator in the above equation (1) can be obtained. Is calculated in advance with respect to the deviation value (Yi-Ya) of, and the sampling root Yi of the deviation between the sampling value Yi of the denominator of Equation (1) and its average value Ya. By storing the information in the memory 21, the subsequent processing speed can be remarkably increased.

Here, as is well known, the absolute value of the correlation coefficient r obtained by the equation (1) is in the range of 0 ≤ | r | ≤ 1, so that the correlation coefficient r is By comparing with a predetermined value stored in advance, it is possible to inspect whether or not the test sample has a predetermined characteristic, and the coefficient r is infinitely close to Γ1 ”. At this time, the coin under test can determine that the coin of the acceptable denomination is true. However, if the coefficient is infinitely close to zero as a result of the inspection, the coin shall be judged to be false. Can be done. Therefore, a value close to 1 which is less than or equal to 1 is set in accordance with the target coin for which the predetermined value of the true / false determination is to be determined, and a correlation coefficient r larger than the set value is obtained. When it is obtained, it is determined to be a genuine coin.

Here, the characteristics of the representative coin measured by the apparatus of the present invention will be described with reference to FIGS. Figure 6 shows the characteristics of the representative coin. Figure 7 is a comparison diagram showing the specifications of the representative coin. In Figure 7, the representative coin is US 5 CENT and NO. The 5 CENTESIMOS coins in Nama are coins whose material (white copper), diameter and thickness are almost similar. Visually, the only difference between the two coins is that the surface design of the coins is different.

FIG. 6 is a characteristic diagram showing the result of measuring the coin by exciting the exciting coil 1 at an exciting frequency of 90 K (Hz) using the apparatus according to the present invention. It is. In Figure 6, the symbol 50 (indicated by the bold line) is for the US 5 CENT coin, and the symbol 51 is for the Panama 5 CENTESIMOS coin. Fig. 6 It can be seen that the difference between the characteristics of the two cores appears in the first peak and the last peak. This is because the eddy current generated on the surface of the coin generates a demagnetizing field characterized by the unevenness of the pattern on the surface of the coin, thereby reducing the electromotive force generated in each of the two receiving coils. It is considered that a significant difference was detected. In the prior art, such a difference as described above could not be detected.

Next, the authenticity of coins is checked using Figs. 4 and 2. The operation of the device 30 will be described in detail.

In Fig. 4, the coin inspection device 30 checks the coin 3 inserted from the coin inlet 31 by the natural fall, and the coin 30 is below the coin inlet 31. Drop it to the coin rail 4 provided at The coin 3 that has fallen into the coil rail 4 does not roll downstream through the coin inlet 31 through the coin passage 6 (Fig.lb). Fall. While the coil 3 moves in the coin passage 6, the outer diameter detection coil 32, the material detection coil 33, the excitation coil 1 for the uneven pattern detection coil 1 and the reception coil 2 Pass through a and 2 b. The device 30 checks the authenticity of the coin 3 while the coin 3 passes through each of the detection coils. If coin 3 is determined to be authentic as a result of the inspection, gate 3 4 is operated by driving distribution solenoid 35 based on the signal output to output terminal 19. Then, Coin 3 is led to a spectacle passage (not shown). However, when coin 3 is determined to be a false loan as a result of the inspection, the coin 3 is not operated and the coin 3 is guided to a fake currency passage (not shown), and a discharge port (not shown) is provided. Discharge.

Here, assuming that coin 3 is a genuine coin, coin 3 guided to the genuine passage continues to fall freely, and eventually falls to coin lane 36. The dust 3 that has fallen into the coin tray 36 is sorted by denomination by well-known sorting means (not shown), and the discharge ports A, B, C, and D provided for each denomination are provided. Emitted from the corresponding outlet.

The outer diameter detection coil 32 and forest quality detection coil 33 A known technique can be used as the detection means.

Here, the operation of the apparatus 30 for inspecting the authenticity of coins by a detection coil for detecting an uneven pattern using the flowchart of FIG. 8 will be described in detail. In FIG. 8, when the power is turned on, the device performs initial settings such as input and output in the MPU 20 in step 100. After the execution of step 100, in the judgment process of step 101, a process of judging whether or not a coin has been injected into the device using the signal of the detection coil is executed. . If it is determined in step 101 that the coin has been input, the program proceeds to the AD conversion process of step 102. If it is determined in step 101 that the coin has not been input, the waiting process is looped so as to wait for the arrival of the coin.

If it is determined in step 101 that the coin has been input, the process proceeds to the AD conversion process of step 102. In the AD conversion process in step 102, when the coin arrives in the detection coil, the signal is received, and the reception coils 2a and 2b of the detection coil for detecting the uneven pattern are received. Sampling of the output signal of the detection circuit 15 which is a signal from the power source is started. The sampling result is temporarily stored in a memory such as the RAM of the MPU 20 進む, and the process proceeds to step 103.

The arithmetic processing in step 103 is performed by calculating the value of the digital signal sequence temporarily stored and held in the memory and the statistics of the acceptable coins previously stored in the memory 21. The value and are calculated by using the above equation (1) to obtain the correlation coefficient r. Proceed to 5 for truth judgment.

In step 105, the true / false judgment is made by comparing the correlation coefficient obtained by the arithmetic processing in step 103 with a predetermined value of the acceptable coin stored in advance. And the correlation coefficient! :〉 When the value is a predetermined value, it is determined that the coin to be inspected is the true one, and the process proceeds to step 106 of processing the genuine coin. However, when it is determined that the correlation coefficient r is smaller than the predetermined value, the coin to be tested is determined to be false, the false coin processing in step 104 is executed, and the process returns to the standby loop.

In this case, it is assumed that the tested coin is determined to be the true one in the truth determination processing in step 105, and the genuine processing in step 106 is performed. Shall be executed. The genuine processing in step 106 executes processing for outputting a genuine signal, a denomination signal, and the like based on the determination result, and returns to the standby loop.

9a and 9b show a configuration of a detector for detecting an uneven pattern according to the second embodiment of the present invention. The difference from the first embodiment described above is that the line 5b connecting the center of the pole face 40a at the longitudinal end of the U-shaped core 40 of the exciting coil 1 is the receiving coil. It is orthogonal to the line 5a connecting the centers of the coils 2a and 2b, and the line 5b passes through the center C1 of the receiving coil 2a and the midpoint M of the center C2 of the receiving coil 2b. Thus, it is only the point where the excitation coil 1 and the reception coils 2a and 2b are provided. The operation and effect are the same as those of the first embodiment, and thus the description thereof is omitted.

FIGS. 10a and 10b are diagrams showing a configuration of a detector for detecting an uneven pattern according to the third embodiment of the present invention. Above The difference from the first embodiment is that the line 5a connecting the centers of the receiving coils 2a and 2b is perpendicular to the coin rail 4 on which the coin 3 rolls and falls. The only difference is that they are shifted in the direction and pass through the central position of the target coin 3. In the case of the third embodiment, since the receiving coils 2 a and 2 b are arranged at the center of the target coin 3, detection is performed based on the difference in the unevenness pattern at the center of the coin 3. Since the values differ, it is suitable for discriminating whether a coin has a hole in the center of the coin or not.

FIGS. 11A and 11B are diagrams showing a configuration of a detector for detecting an uneven pattern according to the fourth embodiment of the present invention. The difference from the first embodiment described above is that the arrangement of the receiving coils is rotated by 90 degrees, and the line 5a connecting the centers of the receiving coils 2a and 2b is the core of the exciting coil 1. This point is orthogonal to the line 5 b connecting the centers of the magnetic pole faces, and intersects at the center of the exciting coil 1. Also in the fourth embodiment, since the receiving coils 2a and 2b are arranged at positions corresponding to the center of the target coin, the uneven pattern is changed at the center of the coin. The fourth embodiment is suitable for the case where true or false is determined for a certain coin and a non-coin.

As described above, the position of the receiving coils 2a and 2b (the position of the exciting coil corresponding to the position of the receiving coil) is determined to be true or false. According to the difference in the concave and convex pattern on the surface of the target coin to be tested (if there is a difference in the concave and convex pattern due to the absence of a hole in the center, the uneven pattern is If there is a difference, etc.), it should be changed.

Further, the present invention excites the exciting coil 1 at a frequency such that the electromagnetic field penetrates only on the surface of the coil and does not penetrate to the center, thereby forming an electromagnetic field, and a vortex generated near the surface of the coin. Since the effect of the demagnetizing field due to the current is measured, it is desirable that the surfaces of the receiving coils 2a and 2b facing the coin be closer to the surface of the coil.

Therefore, as shown in Fig. 12, the position of the reception walls 2a, 2b on the passage wall 7a, that is, the position of the reception walls 2a, 2b in Fig. 1a, By forming the position where the receiving coils 2a and 2b are disposed with a material 200 having high magnetic permeability along the line 5a connecting the centers, the receiving coils 2a and 2b are formed. You may make it form the state which made b substantially close to the coin surface.

In each of the above-described embodiments, the excitation coil 1 is shown as having a U-shape. However, the excitation coil 1 may be formed in any other shape without departing from the gist of the present invention. Is also good.

ADVANTAGE OF THE INVENTION According to this invention, a small and high-performance coin detection apparatus can be provided at low cost with respect to various coins.

Claims

The scope of the claims

1. A method of determining the authenticity of a coin by identifying it.

(a) a step of disposing an exciting coil and a receiving coil in the vicinity of a coil passage so as to be electromagnetically coupled to each other;

(b) a frequency at which the influence of the demagnetizing field due to the eddy current generated on the surface of the coin when the coil passes through the electromagnetic field is detected by the receiving coil; Exciting the exciting coil to generate an electromagnetic field, and detecting an electromagnetic field affected by the demagnetizing field by the receiving coil as an electromotive force signal; and

(c) a step of identifying the coin based on an electromotive force signal detected by the reception coil, the method comprising: determining the authenticity of the coin;

2. The authenticity of a coin according to claim 1, wherein said step (b) includes a step of setting said frequency in accordance with the material of the coin to be identified. How to determine gender.

3. The step (c) samples the electromotive force signal detected by the reception coil at predetermined intervals, and performs statistical processing based on the sampling value. 2. The method according to claim 1, further comprising the step of detecting characteristics of the detection coin.

4. The statistical processing includes a step of obtaining a correlation coefficient with a reference coin, and a step of calculating a coin according to the magnitude of the correlation coefficient. The method for determining authenticity of a coin according to claim 3, comprising a step of identifying the coin.

5. A method of determining the authenticity of a coin by identifying the coin.

(a) a step of disposing the exciting coil near one side of the coin passage so that the magnetic pole is directed to the coin passage inclined at a predetermined angle;

(b) A step of disposing two receiving coils having substantially the same characteristics near the one side of the coil path so as to be electromagnetically coupled to the exciting coil. When ,

(c) a step of exciting the exciting coil at a predetermined frequency to generate an electromagnetic field;

(d) a step of identifying the coin based on signals detected by the two receiving coils when the coin passes through the electromagnetic field. A method for determining the authenticity of a service.

6. In the step (a), a line connecting the center of the magnetic pole with the exciting coil at a predetermined interval from the receiving coil is substantially parallel to the extending direction of the coin passage. The step (b) is to place the two receiving coils above a coin rail arranged in the coin path and The coil according to claim 5, further comprising a step of arranging a line connecting the centers of the two receiving coils so as to be substantially parallel to an extending direction of the coin path. A method for determining the authenticity of a service.

7. The step (a) receives the exciting coil from the receiving coil. A step of arranging the coil at a predetermined interval so that a line connecting the centers of the magnetic poles is substantially perpendicular to the extending direction of the coin passage; b) is a line connecting the two receiving coils above the coin rail arranged in the coin path and connecting the centers of the two receiving coils with the extension of the coin path. 6. The method for judging the authenticity of a coin according to claim 5, comprising a step of arranging the coin so as to be substantially parallel to the direction in which the coin is located.

8. In the step (a), a line connecting the center of the magnetic pole with the exciting coil at a predetermined interval from the receiving coil is substantially parallel to the extending direction of the coin passage. The step (b) is to place the two receiving coils above a coin rail arranged in the coin path. 6. The coil according to claim 5, further comprising a step of arranging a line connecting the centers of the two receiving coils so as to be substantially perpendicular to an extending direction of the coin path. A method to determine the authenticity of an inn.

9. In the coin passage, the coin passing through the coin passage is inclined to one side of the coin passage in which the exciting coil and the receiving coil are disposed. A method for judging the authenticity of a coin according to claim 5, wherein the method is formed on a coin.

10. The step (d) compares a signal detected by the two receiving coils with a previously stored feature of a predetermined denomination, and compares the signal with the feature. A step to judge that the coin is true when it is within the specified tolerance. A method for determining the authenticity of coins according to claim 5, including:

11. The step (d) includes: a bridge circuit means including the reception coil; a differential amplifying means connected to the bridge circuit means; 6. The authenticity of a coin according to claim 5, wherein the coin is identified by using a detecting means connected to the amplifying means and a discriminating circuit means connected to the detecting means. how to.

12. The method according to claim 5, wherein the two receiving coils are differentially connected to the differential amplifying means.

13. The coil according to claim 5, wherein the exciting coil includes a U-shaped magnetic material having the magnetic poles on the same surface and a coil wound around the magnetic material. 13. A method for determining the authenticity of a service.

14. The coin according to claim 5, wherein the step (c) includes a step of setting the frequency according to a material of the coin to be identified. A method for determining the authenticity of a product.

15. The step (d) samples the electromotive force signal detected by the reception coil at predetermined intervals, performs statistical processing based on the sampling value, and performs detection processing. 6. The method for determining authenticity of a coin according to claim 5, comprising a step of detecting a feature of the coin.

16. The statistical processing finds a correlation coefficient with a reference coin and identifies the coin based on the magnitude of the correlation coefficient. The method for determining the authenticity of a coin according to claim 15, including a step.

17 7. A device that determines the authenticity of a coin by identifying it.

An exciting coil and a receiving coil arranged so as to be electromagnetically coupled to each other in the vicinity of the coil path;

The excitation is performed at such a frequency that the influence of a demagnetizing field due to an eddy current generated on the surface of the coin when the coin passes through the electromagnetic field is detected by the receiving coil. Exciting means for exciting the coil to generate an electromagnetic field;

The electromagnetic field affected by the demagnetizing field is detected by the receiving coil as an electromotive force signal,

An identification means for identifying a coin based on an electromotive force signal detected by the reception coil, wherein the apparatus determines the authenticity of the coin.

18. The apparatus for determining authenticity of a coin according to claim 17, wherein the frequency is set according to a material of the coin to be identified.

19. The discriminating means samples the electromotive force signal detected by the reception coil at predetermined intervals, performs statistical processing based on the sampling value, and performs the characteristic of the coin. The apparatus for judging the authenticity of a coin according to claim 17, which detects the coin.

20. The statistical processing finds a correlation coefficient with a reference coin, and identifies the coin based on the magnitude of the correlation coefficient. An apparatus for judging the authenticity of a coin according to claim 19, wherein the apparatus performs the authentication.

2 1. A device that determines the authenticity of a coin by identifying it.

An exciting coil disposed near one side of the coin passage so that a magnetic pole is directed to the coin passage inclined at a predetermined angle;

Two receiving coils having substantially the same characteristics and arranged near the one side of the coin path so as to be electromagnetically coupled to the exciting coil;

Exciting means for exciting the exciting coil at a predetermined frequency to generate an electromagnetic field;

Discriminating means for discriminating the coin based on signals detected by the two receiving coils when the coin passes through the electromagnetic field. apparatus.

22. The exciting coil is arranged at a predetermined distance from the receiving coil such that a line connecting the centers of the magnetic poles is substantially parallel to the extending direction of the coin path. In addition, the two receiving coils are located above the coin rails arranged in the coin passage and the line connecting the centers of the two receiving coils is in the extending direction of the coin passage. A device for judging the authenticity of coins described in Item 21 of the claim, which is arranged so as to be substantially parallel to the coin.

23. The exciting coil is arranged at a predetermined distance from the receiving coil such that a line connecting the centers of the magnetic poles is substantially perpendicular to the extending direction of the coin path. The two receiving cores The coil is arranged such that a line connecting the centers of the two receiving coils above the coin rail arranged in the coin passage is substantially parallel to the extending direction of the coin passage. An apparatus for judging the authenticity of coins according to claim 21, which is arranged in a claim.

24. The exciting coil is arranged at a predetermined distance from the receiving coil such that a line connecting the centers of the magnetic poles is substantially parallel to the extending direction of the coin path. In addition, the two receiving coils extend above the coil rail arranged in the coin path and connect the center of the two receiving coils with the extension of the coin path. A device for judging the authenticity of coins according to claim 21 which is arranged so as to be substantially perpendicular to the direction in which the coins are located.

25. In the coin passage, the coin passing through the coin passage is inclined to one side of the coin passage in which the exciting coil and the receiving coil are disposed. The apparatus for determining the authenticity of coins according to claim 21, wherein the apparatus is formed as described above.

26. The identification means compares a signal detected by the two reception coils with a feature of a predetermined denomination stored in advance, and determines that the signal has a predetermined tolerance for the feature. 22. The apparatus for judging authenticity of a coin according to claim 21, wherein said coin is judged to be true when the coin is inside.

27. The identification means includes a bridge circuit means including the reception coil, a differential amplifier connected to the bridge circuit, and a differential amplifier connected to the differential amplifier. Detection means and 21. The apparatus for determining authenticity of a coin according to claim 21, comprising: a determination circuit connected to the detection means.

28. The apparatus for determining authenticity of a coin according to claim 21, wherein said two receiving coils are differentially connected to said differential amplifying means.

29. The coil according to claim 21, wherein the excitation coil includes a U-shaped magnetic material having the magnetic poles on the same surface and a coil wound on the magnetic material. A device that determines the authenticity of the application.

30. The apparatus for determining authenticity of a coin according to claim 21, wherein the frequency is set according to a material of the coin to be identified.

31. The identification means samples the electromotive force signal detected by the reception coil at predetermined intervals, performs statistical processing based on the sampling value, and detects characteristics of the coin. Apparatus for determining the authenticity of coins described in paragraph 21.

32. The statistical processing is performed by obtaining a correlation coefficient with a reference coin, and identifying the coin based on the magnitude of the correlation coefficient. An apparatus for determining the authenticity of a coin described in the section 31.