JP2000268221A - Coin inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coin inspection device which precisely inspects and identifies the authenticity and kind of coins even when the materials and outer diameters of coins are similar. SOLUTION: Respective coils being an outer diameter detection means 11 for detecting the outer diameter of a coin, a material detection means 12 for detecting the material and a rugged pattern detection means for detecting the ragged pattern of the coin are arranged along a coin path. The rugged pattern detection means 13 is constituted of an exciting coil 1 and two reception coils 2a and 2b arranged so that they are electromagnetically connected to the coil 1. A frequency optimum for the material of the coil of an inspection object is selected and the exciting coil 1 is excited. Capacitor C1a or C1b, C2a or C2b, C3a or C3b in a resonance circuit are switched and the resonance circuit is resonated. The difference of the rugged pattern of the coin is detected by electromotive force generated from the reception coils 2a and 2b and the coin is identified by the outer diameter, the material and the pattern of the coin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for inspecting the authenticity of coins, and more particularly to an apparatus for inspecting the authenticity and type of coins used in vending machines, game machines and the like.

[0002]

2. Description of the Related Art In recent years, electronic devices using an induction coil are mainly used as inspection devices for authenticity and type of coins. This type of coin inspection device generally utilizes free fall of coins, and is provided with a passage for guiding coins inserted from a coin insertion slot. A plurality of sets of induction coils are arranged in the passage, and each set of induction coils is provided with an electromagnetic field which is excited at a different frequency.

[0003] The inspection of coins is based on a well-known principle. When a coin passes through the electromagnetic field, the amount of electric change (frequency change, voltage change, phase change) obtained by the interaction between the electromagnetic field and the coin. ) Is detected to check the authenticity and type of the coin. The coin inspection apparatus in the prior art has many parameters depending on the frequency of the coin, and as shown in U.S. Pat. No. 3,870,137, the coin material, outer diameter,
It has been used as a technique for inspecting thickness and the like.

[0004]

In recent years, coins from other countries have been easily brought in due to borderless technology, and fraudulent acts by those who mistakenly or illegally use those coins have been increasing. Some of these foreign coins have similar materials, outer diameters and thicknesses. For example, the US 5 CENT coin and the Panama 5 CENTESIMOS coin are representative examples. The representative coins as described above differ only in the design (concavo-convex pattern) of the coin surface, and the materials, outer diameters, and thicknesses are almost the same. 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 such an uneven pattern on the surface of the coin,
As a result, the coin as described above could not be determined.

A Japanese 500 yen coin and a Korean 500 yen coin
Won coins are almost the same in material and outer diameter, and have a thickness of 50
The 0 won coin is slightly thicker. Therefore, when this 500-won coin is processed and used as a 500-yen coin, the conventional method of inspecting the authenticity of the coin with the thickness, outer shape, and material of the coin uses the processed 500-won coin and the 500-yen coin. It was difficult to identify.

In the prior art, optical methods such as image processing have been tried as means for discriminating coins as described above. However, the optical device has a problem that dust or the like adheres to the coin, thereby impairing the authenticity determination of the coin. The device is not only large, but also complicated and expensive. SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a coin inspection device that accurately inspects and identifies a coin authenticity and type even when the coins have the same material and outer diameter.

[0007]

The coin inspection apparatus of the present invention includes either one or both of a coin outer diameter detecting means and a material detecting means, and further, an output signal changes depending on a difference in the concave and convex pattern of the coin. An uneven pattern detecting means is provided, whereby the authenticity and type of the coin are determined based on the difference between the outer diameter or / and material of the coin and the uneven pattern of the coin.

The uneven pattern detecting means includes an exciting coil forming a resonance circuit resonating with an exciting frequency, and a receiving coil arranged near the exciting coil to form a resonance circuit. The difference in the concave and convex pattern of the coin is detected by the power, and based on the output signal from either the outer diameter detecting means or the material detecting means, the exciting frequency for exciting the exciting coil is switched by the control means, and the switching is performed. The parameters of each resonance circuit are changed so as to resonate with the excitation frequency. The parameter is changed by switching the capacitance of the capacitor in the resonance circuit including the exciting coil and the capacitor and the receiving coil and the capacitor.

More specifically, the coin inspection device of the present invention comprises:
Either one or both of the coin outer diameter detecting means and the material detecting means are provided, and the uneven pattern detecting means whose output signal changes depending on the difference in the uneven pattern of the coin is provided. The uneven pattern detecting means includes an oscillating circuit means for oscillating a set frequency, an excitation driving means connected to an output of the oscillating circuit means, and two magnetic poles directed to a coin passage inclined at a predetermined angle. And an excitation coil connected to the excitation drive means and forming a resonance circuit together with a capacitor, and an excitation coil electromagnetically coupled to the excitation coil and disposed in the vicinity of the passage wall on one side of the coin path. An electromagnetic field is formed by the two receiving coils arranged having substantially the same characteristics, a capacitor connected to each of the receiving coils to form a resonance circuit, the excitation coil and the reception coil, and includes a resonance circuit by the reception coil. And amplifying and detecting means connected to the bridge circuit means.

Further, the coin inspection device switches a set frequency for exciting the exciting coil based on an output signal from either the outer diameter detecting means or the material detecting means, and resonates at the switched frequency. Control means for changing the capacitance of the capacitor of each resonance circuit; and an output signal from the outer diameter detecting means and / or a material detecting means and an output signal from an amplification detecting means of the uneven pattern detecting means, the outer diameter of the coin. And / or means for determining the authenticity and type of the coin based on the difference between the material and the uneven pattern of the coin.

[0011]

FIG. 1 is a schematic diagram of a coin inspection apparatus 30 according to an embodiment of the present invention for determining the authenticity and type of a coin. An outer diameter detecting coil 32, a material detecting coil 33, an exciting coil 1 of a concave and convex pattern detecting coil, and receiving coils 2a and 2b are arranged along a coin rail 4 as detecting coils for determining the authenticity and type of the coin. I have.

The coin 3 inserted from the coin insertion slot 31 of the coin inspection device 30 falls to the coin rail 4 provided below the coin insertion slot 31 by natural fall. The coin 3 that has fallen on the coin rail 4 falls while rolling on the downstream in the direction away from the coin insertion slot 31 through a coin passage formed by the coin rail 4. The coin 3 passes through the outer diameter detecting coil 32, the material detecting coil 33, the exciting coil 1 of the uneven pattern detecting coil, and the receiving coils 2a and 2b while moving in the coin path 6. Coin inspection device 3
0 inspects and determines the authenticity and type of the coin 3 while the coin 3 passes through each of the detection coils. When it is determined that the coin 3 is genuine as a result of the inspection and discrimination, the sorting solenoid 35 is driven to operate the gate 34 to guide the coin 3 to a genuine coin passage (not shown). However, when the coin 3 is determined to be a fake coin as a result of the inspection, the coin 3 is guided to a fake coin passage (not shown) without operating the gate 34 and is discharged from a discharge port (not shown).

The coin 3 is a genuine coin, and the coin 3 guided to the genuine coin passage continues to fall freely, and eventually falls on the coin rail 36. The coins 3 that have fallen onto the coin rail 36 are sorted by the type of coin determined by a well-known sorting means (not shown), and the discharge ports A, B,
C and D are discharged from corresponding outlets. The detection means of the outer diameter detection coil 32 and the material detection coil 33 described above are well-known and conventional means and are not special. Therefore, detailed description is omitted, and the authenticity of the coin is determined by the thickness change due to the uneven pattern of the coin. The detection coil for determining the type will be described.

FIG. 2 shows an embodiment of a concave / convex pattern detecting coil according to the present invention, which discriminates the authenticity and type of a coin based on a change in thickness due to the concave / convex pattern of the coin. FIG. 2A is a front view, and FIG. 2B is a cross-sectional view. In FIG. 2, a detection coil for detecting a concavo-convex pattern on the coin surface includes one excitation coil 1 and two reception coils 2 a and 2 b, and is arranged on a passage wall 7 a on one side of the coin passage 6. The coin passage 6 is inclined at a predetermined angle at which the coin 3 is guided and dropped, and the coin rail 4 is disposed at the bottom.
And a pair of passage walls 7a, 7b.
As shown in FIG. 2 (b), 7b is arranged perpendicular to the coin drop direction and inclined with respect to the vertical direction so that the coin 3 falls to one of the passage walls 7a. In addition, the passage wall 7 is arranged such that the coin 3 passing through the surface of the coin rail 4 for placing and guiding coins is inclined toward the passage wall 7a.
a, 7b is inclined in the inclination direction.

The two receiving coils have a drum-shaped core as shown in FIG. 3 (b), and a line 5a connecting the center of the two receiving coils above the coin rail 4 is connected to the coin rail 4. They are arranged at predetermined intervals so as to be substantially parallel. On the other hand, the exciting coil 1
As shown in FIG. 2A, a U-shaped core made of a magnetic material is used, and a coil is wound around the core. The exciting coil 1 is arranged above the receiving coil 2,
The center of the pole face of the core is arranged so that the line 5c connecting the centers between the receiving coils 2a and 2b arranged at the predetermined interval substantially coincides with each other and is substantially parallel to the coin rail 4. ing. Further, the magnetic pole surface of the core is arranged so as to be parallel to the surface of the coin 3.

The excitation coil 1 and the reception coils 2a and 2b arranged as described above are electromagnetically coupled to form an electromagnetic field. FIG. 4 shows the coin inspection device 30.
Is a block diagram of a control device in which the MPU 20 that determines the authenticity and type of a coin by software processing is provided, and at least an oscillation circuit unit 21, an AD conversion unit 22, a signal inspection unit 23, and a memory unit 24 are provided. The conventionally known outer diameter detecting means 11 constituted by the outer diameter detecting coil 32 and the material detecting means 12 constituted by the material detecting coil 33 are connected to the AD converting means 22 provided in the MPU 20. .

The oscillating circuit means 21 is constructed by using frequency dividing means connected to divide the internal reference clock by using the MPU 20. To change the oscillation frequency. The output of the oscillating circuit means 21 is connected to the excitation driving means 14 of the uneven pattern detecting means 13 comprising an uneven pattern detecting coil, and the excitation driving means 14 converts the square wave output from the oscillating circuit means 21 into a sine wave. Is output to the output excitation coil 1 in an approximate manner to drive the excitation coil 1.
A capacitor C1a or C1b is connected to the exciting coil 1 so as to resonate at a set predetermined frequency output from the excitation driving means 14 via the switch SW1, thereby forming an LC parallel resonance circuit. The resonance parameter can be changed. Then, an electromagnetic field is generated around the excitation coil 1 according to the output signal of the excitation drive unit 14.

On the other hand, the two receiving coils 2a and 2b configured as described above generate an electromotive force corresponding to the intensity of the electromagnetic field generated by the exciting coil 1. For this purpose, the exciting coil 1 and the receiving coils 2a and 2b are arranged such that the surface of the coin 3 approaches.

The receiving coil 2a has a capacitor C2 via a changeover switch SW2 for changing the resonance parameter.
a, C2b are connected in parallel, the receiving coil 2b is connected in parallel with capacitors C3a, C3b via a changeover switch SW3, and the parallel circuits are connected with resistors R1, R2, respectively, to form a bridge circuit. . A connection point between the receiving coils 2a and 2b, which is an output of the bridge circuit;
The voltage between both connection points between the connection points of the resistors R1 and R2 is input to the amplification detection circuit 15 which amplifies this voltage and performs detection rectification.

When the coin 3 acts in the electromagnetic field configured as described above, an eddy current is generated near the surface of the coin 3 which is excited by the exciting coil 1, and the eddy current becomes a skin effect as the operating frequency increases. As a result, a remarkable demagnetizing field is generated near the outer periphery of the coin. The demagnetizing field current generated near the outer peripheral surface of the coin due to the above phenomenon interacts with the receiving coils 2a and 2b with a slight change in the shape characteristic of the coin surface. The receiving coils 2a and 2b have the coin 3
Generates an electromotive force (hereinafter, this electromotive force is referred to as a "detection signal") in accordance with the change in the demagnetizing field current caused by the change in the shape characteristic of. Further, since the magnetic pole of the exciting coil 1 is disposed near the receiving coils 2a and 2b, a change in the demagnetizing current caused by the electromagnetic field generated from the magnetic pole acting on the coin 3 can be captured in the vicinity of the pole. it can.

Although the demagnetizing current due to the skin effect appears remarkably near the outer periphery of the coin, when the irregularities on the coin surface are remarkable, the change can be detected without being limited to the vicinity of the outer periphery of the coin. This receiving coil 2
The detection signals a and 2b are generated by a bridge circuit including the receiving coils 2a and 2b to generate an AC voltage signal corresponding to the detection signal and output the signal to the amplification detection means 15. The amplification detector 15 amplifies and rectifies the AC voltage signal generated by the bridge circuit, and outputs a DC voltage signal to the AD converter 22 in the MPU 20. The AD converter 22 converts the input DC voltage signal into a digital signal and outputs the digital signal to the signal inspecting unit 23. The signal inspection means 23 inspects whether or not the coin 3 has a predetermined characteristic, and outputs the result of the inspection to the output terminal 25. The output of the signal inspection means 23 is used to drive a sorting solenoid 35, a coin counter (not shown), and the like, which will be described later.

The oscillating circuit means 11 configured as described above outputs a square wave signal having a predetermined frequency set to excite the exciting coil 1. The frequency excited by the exciting coil 1 In order to detect the difference between the concave and convex patterns with high sensitivity, it is desirable that the frequency is such that the electromagnetic field penetrates into the surface of the concave and convex pattern of the coin, does not penetrate to the center, and the influence 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 discriminating between NT coins and 5 CENTESIMOS coins in Panama, the material of these coins is white copper, and when the coin material is white copper, the excitation frequency of the excitation coil 1 is 70K (Hz) to 9K.
A frequency of 0K (Hz) is desirable.

For this reason, the selection of the frequency for exciting the exciting coil 1 is determined by the material of the target coin. For coins having the same outer shape but changing only the thickness, the exciting frequency is sequentially changed and the receiving coils 2a and 2b change the exciting frequency. The detected voltage 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 coin, and this frequency is used as the excitation frequency.

For example, in the case of white copper, the excitation frequency is 7
It was found by experiments that the detection voltage changed most greatly in the range of 0 K (Hz) to 90 K (Hz) in accordance with the change in thickness. This 70K (Hz)-90K (Hz)
At higher or lower frequencies, the change in the detection voltage with respect to the change in the thickness of the coin gradually decreases as the distance from this frequency band increases, and in order to identify the coin by the difference in thickness, that is, the difference in the uneven pattern on the coin surface,
70K (Hz) to 90K (H
The excitation frequency of z) is suitable.

Further, for example, when the material of the target coin is brass, an excitation frequency of about 7 K (Hz) to 10 K (Hz) causes a large change in the output voltage due to a change in the thickness of the coin. Therefore, in order to identify the coin formed of brass by the uneven pattern on the surface, 7K (Hz) to 10K
(Hz), the coin can be efficiently identified.

Therefore, in the present invention, the oscillation frequency (excitation frequency) oscillated by the oscillation circuit means 21 is changed according to the material of the coin to be inspected and identified.
And the switch S corresponding to the changed excitation frequency.
By switching W1, the resonance parameters are changed by selecting the capacitors C1a and C1b so that the resonance by the LC resonance circuit occurs. Further, as described later, the switches SW2 and S
By W3, the capacitors C2a and C2b and the capacitors C3a and C3b are synchronously selected to change the resonance parameter. In the present embodiment, 2
There are two types of excitation frequencies, that is, two types of oscillation frequencies output from the oscillation circuit means 21, and either one is selected. The same frequency may be used as long as the optimum excitation frequency is the same even if the coins to be sorted are two kinds of materials or different materials, and the number, the materials, and the optimum for each material to be sorted out are the same. The number of oscillation frequencies output from the oscillation circuit means 21 is determined in accordance with the excitation frequency, and the capacity of the switched capacitor is determined in accordance with the oscillation frequency.

The excitation driving means 14 receives the square wave signal output from the oscillation circuit means 11, converts the signal into a waveform approximating a triangular wave by a conventionally known method, and outputs the waveform to drive the excitation coil 1. are doing. The LC resonance circuit composed of the exciting coil 1 and the capacitor C1a or C1b resonates at this exciting frequency, and both ends of the exciting coil 1 are driven with a sine waveform as a result.

An AC bridge circuit is configured so as to include the receiving coils 2a and 2b. The impedance formed by the receiving coil 2a and the capacitor C2a or C2b connected in parallel via the switch SW2 is Z1, the receiving coil 2b If the impedance formed by the capacitor C3a or C3b connected in parallel via the switch SW3 is Z2, the impedance of the resistor R1 is Z3, and the impedance of the resistor R2 is Z4, the condition that the AC bridge is in a balanced state is Z1 · Z4 = Z2 · Z
It becomes 3.

Here, as shown in FIG. 4, the output of the bridge circuit is a signal that appears between the connection points of the reception coils 2a and 2b and the connection points of the resistors R1 and R2, and hence the output is now obtained. The voltage across the receiving coil 2a is V1, the current flowing through the impedance Z1 is i1, the voltage across the receiving coil 2b is V2, and the current flowing through the impedance Z2 is i2.
Then, the voltage Vdef of the signal appearing between the two connection points is as follows (provided that the impedance Z3 of the resistor R1 is equal to the impedance Z4 of the resistor R2).

V1 = Z1 · i1 V2 = Z2 · i2 Vdef = V1−V2 Vdef = Z1 · i1−Z2 · i2 In this embodiment, the receiving coil 2a and the capacitor C2a
(Or C2b) and the resonance frequency of the LC resonance circuit,
Since the resonance frequency of the LC resonance circuit formed by the receiving coil 2b and the capacitor C3a (or C3b) is set to be substantially equal to the oscillation frequency output by the oscillation circuit means 21, the impedances Z1 and Z2 are substantially equal and the impedances Z1 and Z2 become substantially equal. The voltage of the signal appearing between the connection points is a voltage signal caused by the difference between the currents i1 and i2.

The amplification detection means 15 receives the AC voltage signal output from the bridge circuit, amplifies the signal into a desired AC voltage signal, performs detection rectification, and converts the signal into a DC voltage signal corresponding to the output of the bridge circuit. The data is converted and output to the AD conversion means 22 built in the MPU 20. AD conversion means 22
Receives analog DC voltage signals output from the outer diameter detecting means 11, the material detecting means 12, and the detecting circuit means 15 of the uneven pattern detecting means, performs sampling at predetermined intervals, and converts a digital signal sequence into a signal. Output to the inspection means 23.

The signal inspection means 23 inputs digital signal sequence data on the amplitude axis output from the AD conversion means 22 and temporarily stores the data in a memory means 24 such as a RAM.
Based on the digital data temporarily stored and held in the RAM, the authenticity and the type of the coin are determined. First, based on the data based on the DC voltage output from the outer diameter detecting means 11, the same true / false and type discrimination based on the coin outer diameter is performed as before, and based on the data based on the output of the material detecting means 12, In the same manner as above, the authenticity and the type of the coin are determined. The discrimination between the authenticity and the type of the coin based on the outer diameter and the material is conventionally known and used, and the details are omitted.

The discrimination between the authenticity and the type of the coin based on the concavo-convex pattern of the coin newly added according to the present invention will be described below. In the present embodiment, the digital data obtained by AD-converting the output of the amplification detection means 15 stored in the memory means 24 and the data string of the denomination previously stored and held in the memory means 24 are used for statistics. A value is obtained, the statistic is compared with a predetermined value stored in the memory means 24 in advance to check whether the statistic has a predetermined characteristic, and the result of the test is output to the output terminal 25. As a specific method for obtaining the statistical value, the following equation for obtaining a correlation coefficient can be used.

[0034]

(Equation 1) In the above formula, N is the number of samples, variable Xi is the value of the digital signal sequence obtained by measuring the test coin with the sampling value, and variable Yi is the acceptable denomination using the apparatus of the present invention. This is a statistical value obtained by sampling measurement. Xa and Ya are the respective average values. MP
If the processing speed of U20 is considered, the deviation (Yi-Ya) between the sampling value Yi of the acceptable denomination in the numerator cross product sum and the average value Ya thereof in the above equation (1),
And the sampling value Yi of the denominator of Equation 1 and its average value Y
By calculating in advance the square root of the sum of squares of the deviation of a and storing the value in the memory means 24, the subsequent processing speed can be remarkably increased.

Since the absolute value of the correlation coefficient r obtained by the equation (1) is in the range of 0 ≦ | r | ≦ 1 as is well known, the correlation coefficient r and the predetermined value stored in advance are used. By comparing, it is possible to inspect whether or not the coin to be inspected has a predetermined characteristic. When the coefficient r is infinitely close to “1”, the coin to be inspected is true with respect to coins of acceptable denominations. Can be determined. However, when the coefficient is infinitely close to zero as a result of the inspection, the coin can be determined to be false. Therefore, a value close to 1 is set to 1 or less in accordance with the target coin for which the predetermined value of the authenticity determination is to be determined, and when a correlation coefficient r larger than the set value is obtained, a genuine coin Of coins.

Here, the characteristics of the representative coin measured by the apparatus of the present invention will be described with reference to FIGS. FIG. 5 is a diagram showing characteristics of the representative coin. FIG. 6 is a comparison diagram showing the specifications of the representative coin. In FIG. 6, the US 5CENT representative coin and the 5CENTESIMOS coin in Panama are coins whose materials (bronze), diameter and thickness are almost similar. If the coin is viewed visually, the only difference between the two coins is that the design of the surface of the coin is different.

FIG. 5 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. In FIG. 5, reference numeral 50 (shown by a thick line) is that of the US 5 CENT coin, and reference numeral 51 is that of the Panama 5 CENTESIMOS coin. From this figure, it can be seen that the difference between the characteristics of the two coins appears at the first peak and the last peak. This is because the eddy current generated on the coin surface generates a demagnetizing field characterized by the unevenness of the pattern on the coin surface, thereby detecting a slight difference between the electromotive forces generated in each of the two receiving coils. Nothing else. In the prior art, such a difference could not be detected.

Next, the processing executed by the MPU of the coin inspection apparatus 30 shown in FIG. 7 will be described with reference to a flowchart.

In FIG. 1, the coin 3 inserted from the coin insertion slot 31 of the coin inspection device 30 falls to the coin rail 4 provided below the coin insertion slot 31 by natural fall, and the coin 3 is moved along the coin rail 4. Passage 6 (FIG. 2)
(B) and falls while rolling to the downstream in the direction away from the coin insertion slot 31. Coin 3 is coin passage 6
While moving inside, the outer diameter detecting means 11 by the outer diameter detecting coil 32, the material detecting means 12 by the material detecting coil 33, the exciting coil 1 and the receiving coil 2 of the uneven pattern detecting coil
The outer diameter, material, and uneven pattern are inspected by the uneven pattern detecting means 13 by a and 2b.

Therefore, first, when power is turned on to the coin inspection device 30, the MPU 20 performs initial settings such as input / output in the MPU 20 (step 100). Thereafter, a process of determining whether or not a coin has been inserted into the device 30 using the signal of the outer diameter detecting means 11 is executed (step 101). The process of determining whether or not the coin has been inserted is repeatedly executed to monitor the insertion of the coin. If it is determined in step 101 that a coin has been inserted,
A process for AD-converting the output signal of the outer diameter detecting means 11 is started. In this AD conversion process, the output signal of the outer diameter detecting means 11 is sampled, and the sampling result is temporarily stored and held in a memory means 24 such as a RAM in the MPU 20 (step 102). From the stored A / D conversion data, a discrimination process is performed based on the authenticity of the inserted coin and the outer diameter of the type in the same manner as in the related art (step 103), and the authenticity and type of the inserted coin are determined (step 104). ).

If the result of the determination is that the coin is a counterfeit coin, the process proceeds to step 112, where a counterfeit coin is processed. That is, the gate 3 is driven without driving the solenoid 35.
Without operating 4, guide coin 3 to a fake coin passage not shown,
It is discharged from a discharge port (not shown). In addition, when the coin is determined to be a genuine coin in the discrimination based on the diameter of the coin type that is permitted to be inserted, that is, when it is determined that the coin has an outer diameter within an allowable range with respect to the outer diameter of the coin of the type that is permitted to be inserted. Then, the output of the oscillating circuit means 22 is switched to an oscillating frequency optimum for detecting a thickness change due to the uneven pattern with respect to the material of the determined coin type. Further, a capacitor constituting a resonance circuit together with the excitation coil 1 and the reception coils 2a and 2b is selected by switching the switches SW1, SW2 and SW3 so as to resonate with the oscillation frequency (step 105). In this embodiment, two groups of different materials (for example, 500 yen for Japanese coins,
The material of each of the 100 yen and 50 yen coins is white copper,
The material of the yen coin is copper. Therefore, it is divided into two groups, white copper and copper.

Even if the material is different, if the optimum excitation frequency for detecting the uneven pattern is substantially the same, it is assumed that the coins are put into the same group. The configuration is such that the optimum excitation frequency can be selected by checking the thickness change due to the concavo-convex pattern for the group material, and the capacitors C1a or C1b, C2a or C2b, and the switches SW1, SW2, and SW3 generate resonance at each frequency. C3a or C3b is selected.

Next, the output signals of the material detecting means 12 and the uneven pattern detecting means 13 are subjected to AD conversion processing, and the converted data is temporarily stored in the RAM of the memory means 24 (step 106). The output signal of the material detecting means 12 is A / D converted and the material is discriminated from the stored data in the same manner as in the prior art (steps 107 and 108). If so, the process proceeds to step 109. That is, the authenticity of the coin is determined based on whether or not the detected value indicating the material is within the allowable range of the value indicating the material of the genuine coin with respect to the outer diameter determined in steps 103 and 104.

As described above, for the inserted coin whose outer diameter and material are determined to be genuine, (in step 109, the output signal of the amplification detector 15 of the uneven pattern detector 13 is AD-converted, and the stored data is , The authenticity of the inserted coin is determined (step 109).

The arithmetic processing of step 109 is performed by storing the data of the output signal of the amplification detection means 15 of the AD-converted concavo-convex pattern detection means 13 temporarily stored and held in the memory means 24 and the data stored in the memory means 21 in advance. A process is performed to obtain a correlation coefficient r with the statistical value of the acceptable coins using the above equation (1). The true / false judgment in step 110 is based on the correlation coefficient r obtained by the arithmetic processing in step 109 and the steps 103 and 104.
Is compared with a predetermined value stored in advance for an acceptable coin determined based on the outer diameter in the processing of the above, and a correlation coefficient r>
When the value is a predetermined value, it is determined that the inserted coin is genuine, and the processing proceeds to the true coin processing of step 110. However, the correlation coefficient r
<When it is determined that the value is the predetermined value, the inserted coin is determined to be false, the false coin processing of step 112 is executed, and the process returns to the standby loop.

Step 111 when it is determined in the authenticity determination processing in step 110 that the inserted coin is genuine
In the genuine money processing, a processing for outputting a genuine money signal, a denomination signal, and the like is performed based on the determination result, and the process returns to the standby loop. When a genuine coin signal is output from the output terminal 19, the sorting solenoid 35 is driven to operate the gate 34, and the coin 3
To the speculum passage (not shown), and then the coin rail 36
To fall. The coins 3 that have fallen on the coin rail 36 are sorted by denomination based on a denomination signal by a well-known distributing means (not shown), and a discharge port A provided for each denomination is provided.
B, C, and D are discharged from corresponding outlets.

In the above-described embodiment, coins inserted and discriminated are divided into two groups according to their materials. Therefore, two capacitors are provided as means for changing the parameters of the oscillation circuit, and one of them is selectively connected. However, the number of capacitors may be increased in accordance with the number of types of coin materials to be determined.

In the above-described embodiment, based on the outer diameter of the coin detected by the outer diameter detecting means, the excitation frequency suitable for the material of the genuine coin corresponding to the outer diameter is selected, and the capacitor is selected. Was switched, but based on the output signal from the material detecting means for detecting the material of the coin,
An excitation frequency and a capacitor suitable for the detection material may be selected. Further, the oscillation circuit formed by the excitation coil and the reception coil may be any oscillation circuit using a coil, and an oscillation circuit other than the above-described embodiment may be used.

[0049]

According to the present invention, in addition to the inspection of the authenticity and the type of the coin based on the outer diameter and the material of the coin, the unevenness pattern on the coin surface can be detected. The device can be provided at low cost.
In addition, since the uneven pattern of the coin is detected by the excitation frequency optimal for the target coin in accordance with the outer diameter and the material of the coin, the authenticity and type of the coin can be more accurately determined.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a coil inspection device according to an embodiment of the present invention.

FIGS. 2A and 2B are diagrams showing a configuration of a detection coil for detecting a concavo-convex pattern in the embodiment, wherein FIG. 2A is a front view and FIG.

3A and 3B are explanatory diagrams of a configuration of a detection coil for detecting a concavo-convex pattern according to the first embodiment. FIG. 3A is a front view of an excitation coil, and FIG. 3B is a cross-sectional view of a reception coil.

FIG. 4 is a schematic block diagram of a circuit in the embodiment.

FIG. 5 is a characteristic diagram showing characteristics of coins having the same material but different patterns.

FIG. 6 is a comparison diagram showing specifications of the coin.

FIG. 7 is a flowchart of an operation according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Exciting coil 2a, 2b Receiving coil 3 Coin 4 Coin rail 6 Coin passage 7a, 7b Passage wall of coin passage

Claims (4)

[Claims] 1. An inspection device for a coin that has been inserted,
Either or both of the outer diameter detecting means and the material detecting means of the coin are provided, and the uneven pattern detecting means whose output signal is changed by the difference of the uneven pattern of the coin is provided. A coin inspection apparatus characterized in that the authenticity and type of a coin are determined based on the difference in the uneven pattern of the coin. 2. An uneven pattern detecting means comprising: an exciting coil forming a resonance circuit resonating at an exciting frequency; and a receiving coil arranged near the exciting coil to form a resonance circuit. Detecting the difference in the concavo-convex pattern of the coin based on the generated electromotive force, and switching the excitation frequency for exciting the excitation coil based on an output signal from either the outer diameter detection means or the material detection means, The coin inspection device according to claim 1, further comprising control means for changing a parameter of each of the resonance circuits so as to resonate with a frequency. 3. The coin inspection device according to claim 2, wherein the resonance circuit includes the exciting coil and the capacitor, and the receiving coil and the capacitor, and the change of the parameter is performed by switching a capacitance of the capacitor. 4. An apparatus for inspecting inserted coins,
Either or both of the outer diameter detection means and the material detection means of the coin are provided, and the uneven pattern detection means whose output signal changes depending on the difference in the uneven pattern of the coin is provided. Oscillating circuit means for oscillating, excitation driving means connected to the output of the oscillating circuit means, and two magnetic poles directed toward the coin passage inclined at a predetermined angle, near the passage wall on one side of the coin passage. An excitation coil which is arranged and connected to the excitation drive means and forms a resonance circuit together with a capacitor; and two reception coils arranged near the passage wall so as to be electromagnetically coupled to the excitation coil and having substantially the same characteristics, A capacitor connected to each of the receiving coils and forming a resonance circuit, and an electromagnetic field is configured by the exciting coil and the receiving coil,
A bridge circuit means configured to include a resonance circuit by the receiving coil, and an amplification detection means connected to the bridge circuit means, wherein the output signal from either the outer diameter detection means or the material detection means A control means for switching a set frequency for exciting the excitation coil, and changing a capacitance of a capacitor of each resonance circuit so as to resonate with the switched frequency; and an outer diameter detecting means or / and a material detecting means. And a means for judging the authenticity and type of the coin based on the difference between the outer diameter or / and material of the coin and the unevenness pattern of the coin, based on the output signal of the coin and the output signal from the amplification detection means of the uneven pattern detection means.