HK1234526B - Coin processing device - Google Patents

Description

Coin processing device

Technical Field

The present invention relates to a coin processing device installed in a vending machine, an exchange machine, an actuary machine, a ticket vending machine, a service device, etc. (hereinafter referred to as "vending machine, etc."), and in particular to a coin processing device having an outer diameter detection sensor for detecting the outer diameter of a coin.

Background Art

A coin processing device is installed inside a vending machine or the like. This coin processing device determines the authenticity of inserted coins and sorts and stores the inserted coins deemed to be genuine by denomination. This coin processing device includes a coin sorting unit that determines the authenticity of inserted coins and sorts the coins by denomination.

The coin sorting unit is equipped with an outer diameter sensor that primarily detects the outer diameter of a coin, and a material detection sensor that primarily detects the material of the coin. The outer diameter detection sensor includes a coil, which is installed in the coin passage through which coins are inserted and connected to an oscillating circuit. The material detection sensor is similar. The oscillating circuit oscillates at a frequency corresponding to the coil's inductance. This oscillation frequency is set to a frequency at which the electromagnetic field generated by the oscillation is easily affected by the coin. As the electromagnetic field is affected by the coin, the amplitude of the oscillation signal also changes. This allows the outer diameter and material of the coin to be detected based on the oscillation frequency and voltage. This allows the authenticity and type of the coin to be determined.

However, coin processing devices sometimes determine the authenticity of multiple coins, including bimetallic coins. Bimetallic coins are coins whose central core is made of a different material than the annular portion surrounding the core. An example of a bimetallic coin is the Canadian two-dollar coin. To accurately detect the outer diameter of such bimetallic coins, a technology using an annular outer diameter detection sensor with a hollow center is known (see Patent Document 1).

With this annular outer diameter sensor, the core of the bimetallic coin overlaps with the sensor, resulting in a significantly lower electromagnetic field (magnetic flux density) at the core than at the annular portion. This allows for highly accurate detection of the bimetallic coin's outer diameter by primarily reflecting the annular portion of the coin's outer circumference.

Patent Document 1: Japanese Patent No. 4126668

However, when using the conventional outer diameter detection sensor, as shown in Figure 13 , the periphery of small coins (e.g., Canadian dimes) other than bimetallic coins (CO) overlaps with the space OP1 of the outer diameter detection sensor 4X. Consequently, as shown in Figure 14 , within the small coin outer diameter range RX, the relationship between the oscillation frequency and the outer diameter becomes disproportionate. Consequently, the outer diameter of small coins cannot be accurately detected, potentially leading to erroneous determination of coin authenticity and type.

Summary of the Invention

The present invention is proposed to solve the above-mentioned problem, and its object is to provide a coin processing device that can improve the detection accuracy of various coin outer diameters.

A coin processing device according to one embodiment of the present invention includes:

A coin channel for the inserted coins to pass through;

a material detection sensor having a first coil and a second coil facing each other in a manner of clamping the coin channel;

The outer diameter detection sensor includes a third annular coil surrounding the first coil and a fourth annular coil surrounding the second coil, wherein the third coil and the fourth coil face each other in a manner of sandwiching the coin passage.

a first oscillation circuit connected to the material detection sensor and oscillating a first oscillation signal in a single connection state, and connected to the material detection sensor and the outer diameter detection sensor connected in series and oscillating the first oscillation signal in a series connection state;

a second oscillation circuit, which, in a single connection state, is connected to the outer diameter detection sensor and oscillates a second oscillation signal;

a switching unit that switches between the individual connection state and the series connection state; and

The coin identification unit detects an outer diameter of the coin using the second oscillation signal in the individual connection state or the first oscillation signal in the series connection state, and identifies the coin based on the outer diameter.

According to the present invention, it is possible to improve the detection accuracy of various coin outer diameters.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a partial schematic structural diagram showing a coin processing apparatus according to one embodiment.

FIG2(a) is a side view showing one side of the recognition sensor, FIG2(b) is a side view showing another side of the recognition sensor, and FIG2(c) is a cross-sectional view showing the coin passage and the recognition sensor.

FIG3 is a block diagram showing a configuration related to authenticity determination and type discrimination of the coin handling apparatus of FIG1 .

FIG. 4 is a circuit diagram showing the connection of a switching unit in a single connection state.

FIG. 5 is a circuit diagram showing the connection of a switching unit in a series connection state.

Figure 6(a) is a diagram showing the positional relationship between bimetallic coins and the identification sensor, Figure 6(b) is a diagram showing the time variation of the frequency and voltage of the outer diameter detection sensor corresponding to Figure 6(a), Figure 6(c) is a diagram showing the positional relationship between coins other than bimetallic coins and the identification sensor, and Figure 6(d) is a diagram showing the time variation of the frequency and voltage of the outer diameter detection sensor corresponding to Figure 6(c).

Figure 7(a) is a diagram showing the positional relationship between bimetallic coins and the identification sensor, Figure 7(b) is a diagram showing the time variation of the frequency and voltage of the material detection sensor corresponding to Figure 7(a), Figure 7(c) is a diagram showing the positional relationship between coins other than bimetallic coins and the identification sensor, and Figure 7(d) is a diagram showing the time variation of the frequency and voltage of the material detection sensor corresponding to Figure 7(c).

Figure 8(a) is a diagram showing the positional relationship between bimetallic coins and the identification sensor, Figure 8(b) is a diagram showing the time variation of the frequency and voltage of the outer diameter and material detection sensor corresponding to Figure 8(a), Figure 8(c) is a diagram showing the positional relationship between coins other than bimetallic coins and the identification sensor, and Figure 8(d) is a diagram showing the time variation of the frequency and voltage of the outer diameter and material detection sensor corresponding to Figure 8(c).

FIG. 9 is a flowchart showing the authenticity determination process and the type determination process of the coin processing apparatus.

FIG10 is a diagram showing the data collection period.

FIG. 11 is a graph showing the relationship between the outer diameter of a coin other than a bimetallic coin and the frequency detected by the coin identification unit in a serially connected state in one embodiment.

FIG. 12 is a graph showing the relationship between frequency and voltage of a clad structure coin according to one embodiment.

FIG. 13 is a diagram showing the positional relationship between a conventional outer diameter detection sensor and a small coin.

FIG. 14 is a graph showing the relationship between the outer diameter of coins other than conventional bimetallic coins and the frequency.

DETAILED DESCRIPTION

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited to this embodiment.

FIG1 is a schematic partial structural diagram of a coin handling device 1 according to one embodiment. As shown in FIG1 , the coin handling device 1 includes an inlet 2 for inserting coins, a coin passage 3 disposed obliquely below the inlet 2 for passing inserted coins, and a recognition sensor 4 provided on a side wall of the coin passage 3. The side wall of the coin passage 3 is not shown.

A coin inserted from the insertion port 2 rolls in the coin passage 3 by its own weight and passes through the identification sensor 4. This allows the authenticity and type of the coin to be determined as described below.

FIG2(a) is a side view showing one side of the recognition sensor 4, and FIG2(b) is a side view showing another side of the recognition sensor 4. FIG2(c) is a cross-sectional view showing the coin passage 3 and the recognition sensor 4 of FIG1 taken along a plane perpendicular to the direction in which the coin CO passes.

The recognition sensor 4 includes a material detection sensor 4a and an outer diameter detection sensor 4b.

The material detection sensor 4a includes a first coil L1 and a second coil L2 facing each other so as to sandwich the coin passage 3. The first coil L1 and the second coil L2 are circular and planar coils. In other words, coins can pass through the material detection sensor 4a.

The outer diameter detection sensor 4b includes a ring-shaped third coil L3 surrounding the first coil L1 and a ring-shaped fourth coil L4 surrounding the second coil L2. The third coil L3 and the fourth coil L4 face each other, sandwiching the coin passage 3. In other words, coins can pass through the outer diameter detection sensor 4b.

In this manner, the outer diameter detection sensor 4b is provided in an annular shape so as to surround the material detection sensor 4a.

The first coil L1 and the third coil L3 are spiral coils arranged in a planar shape on the first printed circuit board. The second coil L2 and the fourth coil L4 are spiral coils arranged in a planar shape on the second printed circuit board. The use of spiral coils makes it possible to easily and accurately determine the relative position of the material detection sensor 4a and the outer diameter detection sensor 4b.

FIG3 is a block diagram showing the structure related to authenticity determination and coin type determination of the coin processing device 1 of FIG1. The coin processing device 1 includes a first oscillation circuit 11 that oscillates a first oscillation signal OSC1, a second oscillation circuit 12 that oscillates a second oscillation signal OSC2, envelope detection circuits 13 and 14, a switching unit 15, a coin identification unit 16, and a storage unit (memory) 17.

The first oscillator circuit 11 includes capacitors C1 and C2, and an amplifier IC1. One end of capacitor C1 is connected to one end of the first coil L1 and to the input terminal of amplifier IC1. The other end of capacitor C1 is connected to one end of capacitor C2 and to ground. The other end of capacitor C2 is connected to one end of the second coil L2 and to the output terminal of amplifier IC1. The signal at the input terminal of amplifier IC1 is the first oscillation signal OSC1. When no coin is present, the frequency of first oscillation signal OSC1 is determined by the inductance connected between the input and output terminals of amplifier IC1 and the capacitance values of capacitors C1 and C2.

The other end of the first coil L1 is connected to the switch S1 of the switching unit 15 . The other end of the second coil L2 is connected to the switch S2 of the switching unit 15 .

The second oscillator circuit 12 includes capacitors C3 and C4, and an amplifier IC2. One end of capacitor C3 is connected to switch S4 of the switching unit 15 and to the input terminal of amplifier IC2. The other end of capacitor C3 is connected to one end of capacitor C4 and to ground. The other end of capacitor C4 is connected to switch S3 of the switching unit 15 and to the output terminal of amplifier IC2. The other end of the third coil L3 is connected to the other end of the fourth coil L4. The signal at the input terminal of amplifier IC2 is the second oscillation signal OSC2. When no coin is present, the frequency of second oscillation signal OSC2 is determined by the inductance connected between the input and output terminals of amplifier IC2 and the capacitance values of capacitors C3 and C4.

The first oscillation signal OSC1 is supplied to the envelope detection circuit 13 and the coin identification unit 16. The envelope detection circuit 13 performs envelope detection on the first oscillation signal OSC1 and outputs the voltage of the first oscillation signal OSC1.

The second oscillation signal OSC2 is supplied to the envelope detection circuit 14 and the coin identification unit 16. The envelope detection circuit 14 performs envelope detection on the second oscillation signal OSC2 and outputs the voltage of the second oscillation signal OSC2.

The switching unit 15 includes switches S1 to S4, which can be switched between a single connection state and a series connection state. In the single connection state, the first oscillator circuit 11 is connected to the material detection sensor 4a, and the second oscillator circuit 12 is connected to the outer diameter detection sensor 4b. In the series connection state, the first oscillator circuit 11 is connected to the material detection sensor 4a and the outer diameter detection sensor 4b connected in series, and the second oscillator circuit 12 is not connected to the material detection sensor 4a or the outer diameter detection sensor 4b.

The coin recognition unit 16 includes, for example, an AD converter and a CPU (Central Processing Unit), and detects the frequencies of the first oscillation signal OSC1 and the second oscillation signal OSC2 . Furthermore, the coin recognition unit 16 controls the switching unit 15 .

The storage unit 17 includes, for example, a RAM (Random Access Memory) or a nonvolatile memory, and stores the voltage and frequency of the first oscillation signal OSC1 and the voltage and frequency of the second oscillation signal OSC2 supplied from the coin recognition unit 16 .

The coin identification unit 16 detects the coin's characteristic values (outer diameter and material) based on the first and second oscillation signals OSC1 and OSC2 using the values stored in the storage unit 17, and identifies the coin based on the detected characteristic values.

Figure 4 is a circuit diagram showing the connections of switching unit 15 in the single-connection state. As shown in Figure 4, in the single-connection state, switches S1 and S2 connect the other end of first coil L1 to the other end of second coil L2. Switch S3 connects one end of third coil L3 to the output terminal of amplifier IC2. Switch S4 connects one end of fourth coil L4 to the input terminal of amplifier IC2. Thus, first coil L1 and second coil L2 are connected in series between the input and output terminals of amplifier IC1, and third coil L3 and fourth coil L4 are connected in series between the input and output terminals of amplifier IC2.

Thus, the first oscillation circuit 11 is connected to the material detection sensor 4a in the single connection state and oscillates the first oscillation signal OSC1. The second oscillation circuit 12 is connected to the outer diameter detection sensor 4b in the single connection state and oscillates the second oscillation signal OSC2.

Figure 5 is a circuit diagram showing the connection of switching unit 15 in a series connection state. As shown in Figure 5, in the series connection state, switches S1 and S3 connect the other end of first coil L1 to one end of third coil L3. Switches S2 and S4 connect the other end of second coil L2 to one end of fourth coil L4. Thus, first coil L1, third coil L3, fourth coil L4, and second coil L2 are connected in series between the input and output terminals of amplifier IC1.

In this manner, the first oscillation circuit 11 is connected in series to the material detection sensor 4 a and the outer diameter detection sensor 4 b connected in series, and oscillates the first oscillation signal OSC1 .

Next, an example of the frequency and voltage of each sensor when a coin passes through the recognition sensor 4 will be described.

(Outer diameter detection sensor 4b in single connection state)

FIG6(a) shows the positional relationship between the bimetallic coin BCO and the recognition sensor 4. FIG6(b) shows the time-varying frequency and voltage of the outer diameter detection sensor 4b corresponding to FIG6(a). The frequency and voltage of the outer diameter detection sensor 4b represent the frequency and voltage of the second oscillation signal OSC2 in the single-connection state.

FIG6(c) is a diagram showing the positional relationship between a coin CO other than a bimetallic coin and the recognition sensor 4, and FIG6(d) is a diagram showing time variations in frequency and voltage of the outer diameter detection sensor 4b corresponding to FIG6(c).

As shown in FIG6(a), when the bimetallic coin BCO is at point P1, the bimetallic coin BCO has not yet reached the outer diameter detection sensor 4b. Therefore, as shown in FIG6(b), the frequency and voltage values of the outer diameter detection sensor 4b are substantially the same as those in the standby state without a coin inserted.

At the next point P2, the end of the bimetallic coin BCO reaches the end of the outer diameter detection sensor 4b, whereby the frequency and voltage of the outer diameter detection sensor 4b start to drop from the values in the standby state.

At the next point P3, the bimetallic coin BCO overlaps the entire outer diameter detection sensor 4b. At this point, the frequency and voltage of the outer diameter detection sensor 4b are at minimum values.

Thereafter, the overlapping area between the bimetallic coin BCO and the outer diameter detection sensor 4b decreases, and the frequency and voltage of the outer diameter detection sensor 4b increase accordingly to the values of the standby state.

6 (c), (d), when the coin CO other than the bimetallic coin is located at points P1a, P2a, and P3a, respectively, the frequency and voltage of the outer diameter detection sensor 4b change in the same manner as the bimetallic coin BCO.

(Material detection sensor 4a in single connection state)

FIG7(a) shows the positional relationship between the bimetallic coin BCO and the identification sensor 4, and FIG7(b) shows the time-varying frequency and voltage of the material detection sensor 4a corresponding to FIG7(a). The frequency and voltage of the material detection sensor 4a represent the frequency and voltage of the first oscillation signal OSC1 in the single-connection state.

FIG7(c) is a diagram showing the positional relationship between a coin CO other than a bimetallic coin and the identification sensor 4, and FIG7(d) is a diagram showing time variations in frequency and voltage of the material detection sensor 4a corresponding to FIG7(c).

As shown in FIG7(a), when the bimetallic coin BCO is at point P1, the bimetallic coin BCO has not reached the material detection sensor 4a. Therefore, as shown in FIG7(b), the frequency and voltage values of the material detection sensor 4a are substantially the same as those in the standby state.

At the next point P2, the annular portion BCO1 of the bimetallic coin BCO reaches the end of the material detection sensor 4a. As a result, the frequency of the material detection sensor 4a changes from the value in the standby state, and the voltage decreases.

At the next point P3, the core BCO2 of the bimetallic coin BCO reaches the end of the material detection sensor 4a. As a result, the frequency of the material detection sensor 4a changes from the value at point P2, and the voltage rises and then decreases from the value at point P2. In other words, the voltage waveform has a peak (concavity) 20 near point P3.

This is because the core BCO2 and the ring BCO1 of the bimetallic coin BCO are made of different materials. Therefore, when the ring BCO1 reaches the material detection sensor 4a, the electromagnetic field is affected to different degrees than when the core BCO2 reaches the material detection sensor 4a.

At the next point P4, the entire material detection sensor 4a overlaps the core BCO2 of the bimetallic coin BCO. The overlapping area between the bimetallic coin BCO and the material detection sensor 4a remains approximately constant before and after point P4. The frequency and voltage of the material detection sensor 4a remain approximately constant.

Thereafter, the overlapping area between the bimetallic coin BCO and the material detection sensor 4a decreases, and as the area decreases, the frequency and voltage of the material detection sensor 4a increase to the values of the standby state. At this time, the voltage waveform also has a peak.

On the other hand, when a coin CO other than a bimetallic coin reaches point P2a, the end of the coin CO reaches the end of the material detection sensor 4a. As a result, the frequency of the material detection sensor 4a changes from the value in the standby state, and the voltage decreases.

At the next point P3a, the area of the coin CO overlapping the material detection sensor 4a increases. As a result, the frequency of the material detection sensor 4a changes from the value at point P2a, and the voltage decreases from the value at point P2a.

Thereafter, within a range where the overlapping area between the coin CO and the material detection sensor 4a before and after the point P4a is substantially constant, the frequency and voltage of the material detection sensor 4a are substantially constant.

Thereafter, the overlapping area between the coin CO and the material detection sensor 4a decreases, and as the area decreases, the frequency and voltage of the material detection sensor 4a increase to the values of the standby state.

As described above, the coin CO other than the bimetallic coin is made of only one material, and therefore the voltage waveform of the material detection sensor 4a does not have a peak.

(Series connection state)

Figure 8(a) shows the positional relationship between the bimetallic coin BCO and the identification sensor 4. Figure 8(b) shows the time-varying frequency and voltage of the outer diameter and material detection sensors corresponding to Figure 8(a). The outer diameter and material detection sensors represent outer diameter detection sensor 4b and material detection sensor 4a connected in series. The frequency and voltage of the outer diameter and material detection sensors represent the frequency and voltage of the first oscillation signal OSC1 when connected in series.

FIG8(c) is a diagram showing the positional relationship between a coin CO other than a bimetallic coin and the recognition sensor 4, and FIG8(d) is a diagram showing the time variation of the frequency and voltage of the outer diameter and material detection sensor corresponding to FIG8(c).

As shown in FIG8 (a), when the bimetallic coin BCO is located at point P1, as shown in FIG8 (b), the frequency and voltage values of the outer diameter and material detection sensor are substantially the same as those in the standby state without inserting a coin.

At the next point P2, the end of the bimetallic coin BCO reaches the end of the outer diameter detection sensor 4b, whereby the frequency and voltage of the outer diameter and material detection sensor begin to decrease from the values in the standby state.

At the next point P3, the core BCO2 of the bimetallic coin BCO reaches the end of the material detection sensor 4a, whereby the outer diameter, frequency, and voltage of the material detection sensor decrease from the values at point P2.

At the next point P4, the entire material detection sensor 4a overlaps the core BCO2 of the bimetallic coin BCO. At this point, the frequency and voltage of the outer diameter detection sensor 4b are at minimum values.

Thereafter, the overlapping area between the bimetallic coin BCO and the outer diameter and material detection sensor decreases, and the frequency and voltage of the outer diameter and material detection sensor increase to the standby state value.

As shown in Figures 8(c) and 8(d), when the position of a coin (CO) other than a bimetallic coin changes from point P1a to P2a or P3a, the frequency of the outer diameter and material detection sensor changes, and the voltage decreases. At points P3a and P4a, the overlapping area between the coin (CO) and the outer diameter and material detection sensor remains constant, and the frequency and voltage of the outer diameter and material detection sensor remain constant.

Next, the authenticity determination and type determination processing will be described with reference to FIG9 and FIG10.

Fig. 9 is a flowchart showing the authenticity and type determination process of the coin processing apparatus 1. The process of Fig. 9 is performed under the control of the coin identification unit 16. Fig. 10 is a diagram showing the data collection period, corresponding to Figs. 6(b) and (d) above.

First, after the power is turned on, the device is set to a single connection state (step S1).

Then, the voltage of the outer diameter detection sensor 4b (the standby voltage Vs in FIG. 10 ) is stored in the storage unit 17 (step S2).

Then, the voltage of the outer diameter detection sensor 4b is measured (step S3).

If the voltage of the outer diameter detection sensor 4b does not reach 80% of the standby voltage Vs (No in step S4), the coin has not reached the vicinity of the outer diameter detection sensor 4b, and the process returns to step S3.

When the voltage of outer diameter detection sensor 4b reaches 80% of standby voltage Vs (Yes in step S4, time t1 in Figure 10), the coin has reached the vicinity of outer diameter detection sensor 4b, and the voltage and frequency of outer diameter detection sensor 4b are stored in storage unit 17 (step S5). This time t1 is the start point of data collection.

Then, the voltage and frequency of the material detection sensor 4a are stored in the storage unit 17 (step S6).

Then, the connection is switched to a series connection state (step S7).

Then, the voltage and frequency of the outer diameter and material detection sensor are stored in the storage unit 17 (step S8).

Then, the state is switched to the individual connection state (step S9).

If the voltage of the outer diameter detection sensor 4b has not returned to 85% of the standby voltage Vs (No in step S10), the process returns to step S5. In this way, the switching unit 15 alternates between the individual connection state and the series connection state.

When the voltage of outer diameter detection sensor 4b returns to 85% of standby voltage Vs (Yes in step S10, time t2 in Figure 7 ), the coin is determined to be bimetallic based on the voltage waveform of material detection sensor 4a stored in storage unit 17 (step S11). Specifically, time t2 in Figure 7 marks the end of data collection, and the period between times t1 and t2 constitutes the data collection period.

In this embodiment, as an example, the coin identification unit 16 determines whether a coin is bimetallic based on the voltage of the first oscillating signal OSC1 in the single connection state while the coin passes between the first coil L1 and the second coil L2 (material detection sensor 4a). The coin identification unit 16 then selects either the second oscillating signal OSC2 in the single connection state or the first oscillating signal OSC1 in the series connection state. In other words, the coin identification unit 16 determines whether the coin is bimetallic based on the difference in voltage waveform (Figures 7(b) and (d)) at the material detection sensor 4a.

Specifically, when the voltage waveform of the first oscillation signal OSC1 has a peak value during a predetermined judgment period while the coin passes between the first coil L1 and the second coil L2, the coin identification unit 16 determines that the coin is a bimetallic coin and selects the second oscillation signal OSC2 in a single connection state.

Furthermore, when the voltage waveform of the first oscillation signal OSC1 does not have a peak during the determination period, the coin identification unit 16 determines that the coin is other than a bimetallic coin and selects the first oscillation signal OSC1 in the series connection state.

The determination period may be, for example, the period from point P1 to point P3 in FIG. 7( b ) and the corresponding period in FIG. 7( d ).

In the case of bimetallic coins (YES in step S11), the outer diameter is detected using the frequency of the outer diameter detection sensor 4b (the selected second oscillation signal OSC2) stored in the storage unit 17, and the coin is identified based on the outer diameter (step S12). For example, the minimum frequency value can be compared with a frequency determination threshold value, and the outer diameter can be detected based on the comparison result.

Next, the material is detected using the voltage of the outer diameter detection sensor 4b, the frequency of the material detection sensor 4a, and the voltage of the outer diameter and material detection sensors stored in the storage unit 17, thereby identifying the coin based on the material (step S13). For example, the minimum voltage value can be compared with a voltage determination threshold, and the minimum frequency value can be compared with a frequency determination threshold, and the material can be detected based on these comparison results. The voltage determination threshold and frequency determination threshold can be pre-stored in the storage unit 17.

In step S13 , the material may be detected using at least one of the voltage of the outer diameter detection sensor 4 b , the frequency of the material detection sensor 4 a , the voltage of the material detection sensor 4 a , and the outer diameter and the voltage of the material detection sensor.

On the other hand, if the coin is not bimetallic (No in step S11), the outer diameter is detected using the frequency of the outer diameter and material detection sensor (the selected first oscillation signal OSC1) stored in the storage unit 17, and the coin is identified based on the outer diameter (step S14). For example, the minimum value of the frequency can be compared with a judgment threshold, and the outer diameter can be detected based on the comparison result.

The material of the coin is then detected using the voltage of the outer diameter detection sensor 4b, the frequency and voltage of the material detection sensor 4a, and the voltage of the outer diameter and material detection sensors stored in the storage unit 17, thereby identifying the coin based on the material (step S15). For example, the minimum voltage value can be compared with a voltage judgment threshold, and the minimum frequency value can be compared with a frequency judgment threshold, and the material can be detected based on these comparison results.

In step S15 , the material may be detected using at least one of the voltage of the outer diameter detection sensor 4 b , the frequency of the material detection sensor 4 a , the voltage of the material detection sensor 4 a , the outer diameter, and the voltage of the material detection sensor.

In this way, the coin identification unit 16 detects the outer diameter of the coin based on the second oscillation signal OSC2 in the individual connection state or the first oscillation signal OSC1 in the series connection state.

Furthermore, the coin identification unit 16 can detect the material of the coin using at least one of the first oscillation signal OSC1 in the individual connection state, the second oscillation signal OSC2 in the individual connection state, and the first oscillation signal OSC1 in the series connection state.

Figure 11 is a graph showing the relationship between the outer diameter of coins other than bimetallic coins and the frequency detected by the coin identification unit 16 in a series connection state according to one embodiment. In the series connection state, the electromagnetic field reaches the entire coin regardless of its outer diameter. Therefore, as shown in Figure 11, the frequency detected by the coin identification unit 16 decreases in proportion to the outer diameter. This allows for highly accurate outer diameter detection even of small coins.

Figure 12 is a graph showing the relationship between frequency and voltage for a coin with a clad structure according to one embodiment. The frequency of the material detection sensor 4a in the standalone state is set to _Finitial , while the frequency in the series state is set to _Flow . The inductance of the series state is greater than that of the material detection sensor 4a. Therefore, when no coin is present, the frequency Flow is _lower than the frequency _Finitial .

By using two frequencies, _Finitial and _Flow , the material can be detected at two surface depths. This allows for detection of the material of each layer of coins, including those made of multiple layers of material, such as plated or clad coins, in addition to bimetallic coins. This improves material detection accuracy.

In the example of Figure 12, the material of a test coin having a core material and a cladding material covering the core material is detected. At a frequency of _Finitial , the electromagnetic field is primarily affected by the surface material, allowing detection of the surface material. At a frequency of _Flow , the electromagnetic field is primarily affected by the core material, allowing detection of the core material. In this example, due to the influence of the coin, the frequencies _Flow and _Finitial are approximately equal.

As shown in the figure, when the frequency F is _low in the single connection state, the voltage is high, while when the frequency F _{is low} in the series connection state, the voltage is low. This allows for different voltages to be obtained in the two connection states, making it possible to detect coins with core and surface materials of different materials.

Although not shown in the figure, as described above, by using the voltage of the outer diameter detection sensor 4b, the frequency and voltage of the material detection sensor 4a, and the voltage of the outer diameter and material detection sensors, the material of each layer in the multilayer material can be further detected with high precision based on the three frequencies.

As described above, in this embodiment, a material detection sensor 4a and an annular outer diameter detection sensor 4b surrounding the material detection sensor 4a are provided. When the coin to be inspected passes through, whether the coin is a bimetallic coin is determined by judging whether the voltage waveform of the material detection sensor 4a has a peak.

Furthermore, if the coin is not a bimetallic coin, the outer diameter is detected using the outer diameter of the material detection sensor 4a and the outer diameter detection sensor 4b connected in series, as well as the frequency of the material detection sensor. This allows the electromagnetic field to reach the entire surface of the coin, even for coins with a small outer diameter, through the material detection sensor 4a and the outer diameter detection sensor 4b. Consequently, regardless of the coin's outer diameter, the outer diameter is proportional to the frequency, enabling high-precision outer diameter detection.

On the other hand, when the coin is determined to be a bimetallic coin, the outer diameter is detected using the frequency of the annular outer diameter detection sensor 4b. Therefore, the annular portion of the outer circumference of the bimetallic coin can be reflected, and the outer diameter can be detected with high accuracy.

This can improve the detection accuracy of various coin outer diameters.

Regardless of the type of coin, the material can be detected using the voltage of the outer diameter detection sensor 4b, the frequency and voltage of the material detection sensor 4a, and the voltage of the outer diameter and material detection sensors.

The ability to use three frequencies increases the amount of information available. Specifically, the depth to which the electromagnetic field reaches varies depending on the frequency. Therefore, even in the case of plated or clad coins made of multiple layers, the surface and internal materials can be distinguished and detected based on the frequency.

This can also improve the detection accuracy of various coin materials.

Furthermore, the first to fourth coils L1 to L4 may be formed by winding a conductive wire around a core made of a ferrite material or the like.

Furthermore, an example of alternating between the individual connection state and the series connection state, storing the voltage and frequency, and determining whether the coin is bimetallic after the data collection period has ended has been described, but the present invention is not limited to this. For example, it is possible to determine whether the coin is bimetallic at a time approximately corresponding to point P3 in Figure 7(b). Thereafter, based on the determination result, the individual connection state or the series connection state is fixed, and the obtained voltage and frequency are used to determine the outer diameter and material.

While several embodiments of the present invention have been described above, these embodiments are merely examples and the scope of the present invention is not limited thereto. These embodiments may be implemented in various other ways, and various omissions, substitutions, and modifications may be made without departing from the gist of the present invention. These embodiments and their variations are included within the scope and gist of the invention, and are also included within the invention described in the claims and their equivalents.

Explanation of symbols

1 Coin handling device

2 Input port

3 Coin Channel

4 Identification sensor

4a Material detection sensor

4b Outer diameter detection sensor

L1 first coil

L2 Second coil

L3 third coil

L4 fourth coil

11. First oscillation circuit

12. Second oscillation circuit

13, 14 Envelope Detection Circuit

15 Switching Unit

16 Coin Identification Unit

17 Storage

Claims (14)

1. A coin processing device, characterized by comprising: A coin channel for the inserted coins to pass through; a material detection sensor having a first coil and a second coil facing each other in a manner of clamping the coin passage; The outer diameter detection sensor includes a third annular coil surrounding the first coil and a fourth annular coil surrounding the second coil, wherein the third coil and the fourth coil face each other in a manner of sandwiching the coin passage. a first oscillation circuit connected to the material detection sensor and oscillating a first oscillation signal in a single connection state, and connected to the material detection sensor and the outer diameter detection sensor connected in series and oscillating the first oscillation signal in a series connection state; a second oscillation circuit, in the single connection state, connected to the outer diameter detection sensor and oscillating a second oscillation signal; a switching unit that switches between the individual connection state and the series connection state; and The coin identification unit detects an outer diameter of the coin using the second oscillation signal in the individual connection state or the first oscillation signal in the series connection state, and identifies the coin based on the outer diameter. 2. The coin processing device according to claim 1, characterized in that The coin identification unit selects the second oscillation signal in the single connection state or the first oscillation signal in the series connection state according to the first oscillation signal in the single connection state during the process of the coin passing between the first coil and the second coil, and uses the selected first oscillation signal or the second oscillation signal to detect the outer diameter of the coin. 3. The coin processing device according to claim 2, characterized in that The coin identification unit selects the second oscillation signal in the single connection state if the voltage waveform of the first oscillation signal has a peak value during a predetermined judgment period when the coin passes between the first coil and the second coil; and selects the first oscillation signal in the series connection state if the voltage waveform of the first oscillation signal does not have a peak value during the judgment period. 4. The coin processing device according to any one of claims 1 to 3, characterized in that: The coin identification unit detects the material of the coin using the first oscillation signal in the single connection state, and identifies the coin based on the material and the outer diameter. 5. The coin processing device according to claim 4, characterized in that The coin identification unit detects the material of the coin using the first oscillation signal in the individual connection state and the first oscillation signal in the series connection state. 6. The coin processing device according to any one of claims 1 to 3, characterized in that: The coin processing device further includes a storage unit for storing the voltage and frequency of the first oscillation signal and the voltage and frequency of the second oscillation signal. The switching unit alternately switches between the individual connection state and the series connection state. The coin identification unit identifies the coin using the value stored in the storage unit. 7. The coin processing device according to claim 4, characterized in that The coin processing device further includes a storage unit for storing the voltage and frequency of the first oscillation signal and the voltage and frequency of the second oscillation signal. The switching unit alternately switches between the individual connection state and the series connection state. The coin identification unit identifies the coin using the value stored in the storage unit. 8. The coin processing device according to claim 5, characterized in that The coin processing device further includes a storage unit for storing the voltage and frequency of the first oscillation signal and the voltage and frequency of the second oscillation signal. The switching unit alternately switches between the individual connection state and the series connection state. The coin identification unit identifies the coin using the value stored in the storage unit. 9. The coin processing device according to any one of claims 1 to 3, characterized in that: The first coil and the third coil are spiral coils arranged in a planar shape on a first substrate. The second coil and the fourth coil are spiral coils provided in a planar shape on a second substrate. 10. The coin processing device according to claim 4, characterized in that The first coil and the third coil are spiral coils arranged in a planar shape on a first substrate. The second coil and the fourth coil are spiral coils provided in a planar shape on a second substrate. 11. The coin processing device according to claim 5, characterized in that: The first coil and the third coil are spiral coils arranged in a planar shape on a first substrate. The second coil and the fourth coil are spiral coils provided in a planar shape on a second substrate. 12. The coin processing device according to claim 6, characterized in that The first coil and the third coil are spiral coils arranged in a planar shape on a first substrate. The second coil and the fourth coil are spiral coils provided in a planar shape on a second substrate. 13. The coin processing device according to claim 7, characterized in that: The first coil and the third coil are spiral coils arranged in a planar shape on a first substrate. The second coil and the fourth coil are spiral coils provided in a planar shape on a second substrate. 14. The coin processing device according to claim 8, characterized in that The first coil and the third coil are spiral coils arranged in a planar shape on a first substrate. The second coil and the fourth coil are spiral coils provided in a planar shape on a second substrate.