JPH064737A - Coin sensor - Google Patents

Abstract

PURPOSE:To provide the coin sensor which can surely sort coins if the coins have any diameter difference even among coins composed of the almost same material and can speedily discriminate coins in the case of discriminating prescribed coins. CONSTITUTION:A first transmission side coil 20 is provided at the almost center of a coin when the coin rolls over, a second transmission side coil 20u is provided adjacently to the first transmission side coil 20 and when received data satisfy prescribed conditions, signals are supplied only to the first transmission side coil 20. On the other hand, when the received data do not satisfy the prescribed conditions, signals are supplied to the first transmission side coil 20 and signals are supplied to the second transmission side coil 20u as well.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coin sensor used in a coin sorter or the like.

[0002]

2. Description of the Related Art A conventional coin sensor used in a coin sorter or the like utilizes a coil installed on a wall of a coin passage and the inductance of the coil changes when a coin approaches the coil. A sine wave current of about several kHz is applied to the coil. However, when trying to select coins in this way, among the coin series of aluminum series (1 yen), brass series (5 yen), copper series (10 yen), white copper series (50 yen, 100 yen, 500 yen) It is possible to sort the series, but among the bronze coins, it is not possible to sort between 50 yen coins and 100 yen coins, and also between 500 yen coins and 500 won coins. There is a drawback that you cannot do it.

To overcome this drawback, the Applicant has proposed a coin screening method which uses two signals of different frequencies. That is, the coil on the transmitting side and the coil on the receiving side are opposed to each other with the coin passage interposed therebetween, and a low-frequency current (for example, 10 kHz) and a high-frequency current (for example, 160 kHz) are alternately applied to the coil on the transmitting side to make the receiving side. Both signals are received by the coil and the minimum value of the low frequency voltage component,
The coins are sorted based on the minimum value of the high frequency voltage component. That is, when a coin exists between the coil on the transmitting side and the coil on the receiving side, an eddy current flows in the coin, which causes the electromagnetic field component generated on the transmitting side to be transmitted to the coil on the receiving side. Although the field component is attenuated, the amount of this attenuation varies from coin to coin, and even if two coins have the same amount of attenuation in a low-frequency electromagnetic field, they have different amounts of attenuation in a high-frequency electromagnetic field. Therefore, if two signals with different frequencies are used, the copper-based 500
It is possible to reliably select coins of almost the same shape such as a yen coin and a 500 won coin.

[0004]

However, since the coin of 500 yen and the coin of 1 ruble are almost the same in material, the above conventional device cannot select between them. However, the diameter of a coin of 500 yen is 26.5 millimeters, the diameter of a coin of one ruble is 27.0 millimeters, and the diameter between them is 0.5.
Although there is a millimeter difference, it is difficult to distinguish such a difference by the conventional technique.

It is an object of the present invention to provide a coin sensor which can discriminate coins of substantially the same material if they have slightly different diameters and can discriminate a predetermined coin quickly. It is what

[0006]

According to the present invention, when a coin rolls, a first transmitting side coil is provided substantially in the center of the coin, and a second transmitting side coil is provided close to the first transmitting side coil. A coil is provided, and when the received data satisfies the predetermined condition, the signal is supplied only to the first transmitting coil, while when the received data does not satisfy the predetermined condition,
The signal is supplied to the first transmitting side coil and also to the second transmitting side coil.

[0007]

According to the present invention, when the received data satisfies the predetermined condition, the signal is supplied only to the first transmitting side coil, so that the coin type can be quickly discriminated. When the condition is not satisfied, the signal is supplied to the first transmitting coil and the signal is also supplied to the second transmitting coil, so that the difference in coin diameter can be discriminated.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory view of an embodiment of the present invention.
1 (1) is an overall configuration diagram thereof, and FIG. 1 (2) is
FIG. 3 is an explanatory diagram showing the relationship between the first transmitting side coil 20 and the second transmitting side coil 20u in the above embodiment, and FIG.
FIG. 3 is a circuit diagram showing a specific example of the signal generating circuit 10 in the above embodiment. The transmission side coils 20 and 20u are installed at positions where the reception side coil 30 can receive the respective electromagnetic field components of the transmission side coils 20 and 20u.
And 20u are installed close to each other.

First, the signal generation circuit 10 has a frequency of 160 kHz.
And sine wave signals of 10 kHz are generated internally, and C
The PU 60 is a circuit in which the output frequency is switched and the destination of the generated signal is controlled. The high-frequency signal generation circuit 11 generates a sine wave signal of 160 kHz, and 10 k
Low frequency signal generating circuit 12 for generating a sine wave signal of Hz
, Switches 13, 14, 16, 17 and inverter 1
5 and 18. The switch 13 is turned on when the first switching signal from the CPU 60 is the H signal (High signal), and is a high frequency signal (160 kHz sine wave signal).
To the transmission side coils 20 and 20u, and the switch 14
When the first switching signal from the CPU 60 is the L signal (Low signal), it is inverted by the inverter 15 and turned on, and the low frequency signal (10 kHz sine wave signal) is sent to the transmission side coils 20 and 20u. It is a thing. The switch 16 is turned on when the second switching signal from the CPU 60 is the H signal and sends the signal to the transmission side coil 20, and the switch 17 is the second switching signal from the CPU 60 being L.
When it is a signal, it is inverted by the inverter 18 and turned on, and sends the signal to the transmission side coil 20u.

The transmitting side coils 20 and 20u are 160 kHz.
The receiving side coil 30 is a coil that allows a sine wave current of z and 10 kHz to flow, and the receiving side coil 30 is a coil that faces the transmitting side coils 20 and 20u and receives signals from the transmitting side coils 20 and 20u. The transmission side coils 20, 20u and the reception side coil 30 are wound around ferrite cores 21, 21u, 31 via bobbins (not shown), respectively. A coin passage 71 is provided between the transmission side coils 20 and 20u and the reception side coil 30, and the coin 70 rolls on the floor 72 of the coin passage 71. In addition, of the coin passage 71
A portion (coin detection area) located between the transmitting side coils 20 and 20u and the receiving side coil 30 is made of a material other than a conductor, for example, plastic. The length of the ferrite core 21u is shorter than that of the ferrite core 21.

Further, unlike the distance H1 from the floor 72 of the passage to the first transmitting side coil 20 and the distance H2 from the floor 72 to the second transmitting side coil 20u, the floor 72 to the first transmitting side coil 20 is different. The distance H1 to 20 is shorter than the distance H2 from the floor 72 to the second transmitter coil 20u. That is, the second transmission side coil 20u is installed in the vicinity of the first transmission side coil 20, and the coin 70 passes through the passage 7.
The center of the first transmitting coil 20 is installed at substantially the same height as the center position of the coin 70 when rolling 1 and the upper end of the coin 70 when the coin 70 is rolling in the passage 71. The second transmitter coil 2 is located at almost the same height as the locus of the part.
The center of 0u is installed. The first transmitting side coil 20 and the receiving side coil 30 mainly detect a difference in material of the coin 70, and the second transmitting side coil 20u.
The receiving side coil 30 mainly detects the difference in diameter of the coin 70.

Further, the differential amplifier circuit 40 is for amplifying the signal received by the receiving coil 30, the diode 51 rectifies the output signal of the differential amplifier circuit 40, and the capacitor 52 the rectified signal. Is smoothed and the peak value of the data is held. The electric charge charged in the capacitor 52 is constantly discharged through the resistor 53, but the switch 54 changes the electric charge charged in the capacitor 52 to
All the data is discharged after the data is taken in, and its on / off control is performed by the CPU 60, and is synchronized with the data taking operation. Further, when the discharge time is sufficient, the switch 54 may not be provided and spontaneous discharge may be performed. The A / D conversion circuit 55 converts an analog signal indicating the voltage across the capacitor 52 into a digital signal.

The CPU 60 always keeps the high frequency current (16
0 kHz) is sent to the transmission side coil 20, and the transmission side coil 2
The reception level (detection level) decreases to a value of a predetermined ratio (75%) of the reception level (non-shielding level) of the reception side coil 30 when the coin 70 does not pass between 0 and the reception side coil 30. When it is done, the discrimination of coins is actually started. That is, the first transmitting coil 2
A high-frequency signal and a low-frequency signal are supplied to 0, and when the level of the reception data of the high-frequency signal is higher than the level of the reception data of the low-frequency signal, a signal is sent to the first transmission-side coil 20. And does not supply a signal to the second transmitting coil 20u. On the other hand, when the above conditions are not satisfied, the signal is supplied to the first transmitting coil 20 and to the second transmitting coil 20u. Is also an example of means for controlling to supply a signal.

That is, the CPU 60 supplies a signal to the first transmitting side coil and does not supply a signal to the second transmitting side coil when the received data satisfies a predetermined condition.
On the other hand, when the received data does not satisfy the predetermined condition, the signal is supplied to the first transmitting coil and the signal is also supplied to the second transmitting coil.

Next, the operation of the above embodiment will be described.

First, the basic operation of the above embodiment will be described. FIG. 3 is an explanatory diagram of the basic operation of the above embodiment,
FIG. 3 (1) is a diagram showing a state in which a coin 70a having a relatively short diameter has passed, and FIG. 3 (2) is a diagram showing a state in which a coin 70b having a relatively long diameter has passed.

In FIG. 3 (1), since the diameter of the coin 70a is relatively short, the coil 20u from the transmitter coil 20u
Of the electromagnetic wave components that go toward 0, there are few components that are attenuated by the coin 70a. On the other hand, in FIG.
Since the diameter of 0b is relatively long, the coin 7
Many components are attenuated by 0b. Therefore, while the coins 70a and 70b pass through the coin detection area, the voltage components output by the receiving side coil 30 are different, and the receiving side coil 30 when the coin 70a having a short diameter passes through.
The minimum output voltage is higher than the minimum output voltage of the receiving coil 30 when the coin 70b having a long diameter passes. The difference in the diameter of the passing coin is detected by the difference in the output voltage.

Since the length of the ferrite core 21u is shorter than that of the ferrite core 21, the overall shape of the coin sensor becomes small.

FIG. 4 is a flow chart showing the operation of the above embodiment.

First, initialization is performed (S1), and the coin 7
When 0 is not rolling in the coin passage 71, the reception level V160 at which the reception side coil 30 receives the electromagnetic wave component of 160 kHz generated in the transmission side coil 20 is measured (S2). That is, the signal generation circuit 1 outputs the signal of 160 kHz to the transmission side coil 20 when the power supply is activated.
CPU 60 commands 0 to send side coil 20 160 k
Hz signal flows, the receiving side coil 30 receives the 160 kHz signal, the amplifier circuit 40 amplifies, and the diode 51
Passes only the positive half-wave component, and the capacitor 52 holds the positive peak value.

Although not shown in the figure, the amplifier circuit 4
A diode connected to the output terminal of 0 in the opposite direction to the diode 51, a capacitor for holding a negative peak value, a resistor similar to the resistor 53, a switch similar to the switch 54, A subtracter is provided for calculating the difference between the negative peak value and the positive peak value (that is, peak-peak value). Then, the peak-peak value is converted into a digital value by the A / D conversion circuit 55, and the CPU 60 takes in the digital value. The reception level V160 at this time is stored in the variable V0 as the non-shielding level (S3).

Then, the current reception level V160 is measured (S4), and the reception level V160 at this time is set to the variable V1.
(S5), the current reception level V160 is compared with the value of 75% of the non-shielding level V0 (S6). Here, the value of 75% of the non-shielding level V0 is the non-shielding level V0.
It is a value obtained by subtracting a value obtained by shifting the digital value of the non-shielding level V0 by 2 bits to the right (25% value of the non-shielding level V0) from the digital value of 0 (100% of the non-shielding level V0). . If the current reception level V160 is higher than the value of 75% of the non-shielding level V0, the non-shielding level V0 is used as it is until one minute elapses (S7), and the current reception level V160 is sampled every sampling. Is repeated with the value of 75% of the non-shielding level V0 (S4, S5, S6), and after 1 minute, the process returns to S2 to update the value of the non-shielding level V0 (S2, S3),
The current reception level V160 is 75% of the unshielded level V0.
Compare with the value of.

On the other hand, if the current reception level V160 is less than 75% of the non-shielding level V0 (S6), it can be determined that a coin is present in the coin detection area, and the coin determination operation is started in earnest. To do. That is, the CPU 60 instructs the signal generation circuit 10 to flow a signal of 10 kHz to the transmission side coil 20, and at this time, the transmission side coil 2
The receiving side coil 3 receives the electromagnetic wave component of 10 kHz generated at 0
0 measures the reception level V10 received (S11), and at this time, the size of the reception level V160 and the reception level V10 are measured.
The size of 10 is compared (S12).

If the reception level V160 is lower than the reception level V10, it may be a coin of 500 yen, and thus may be a 1-ruble coin of the same material as the coin of 500 yen. It is not possible to distinguish between a coin of 500 yen and a coin of 1 ruble by judging only the material, and it is necessary to judge the size of the diameter of the coin. That is, the first transmitting coil 2
The coin 7 inserted by sending a signal to the second transmitting side coil 20u installed at a position higher than 0
Examine the 0 diameter. In this case, the signal generation circuit 1 is configured so that a signal of 160 kHz is supplied to the second transmission side coil 20u.
The CPU 60 commands 0 to measure the reception level V160u in which the reception side coil 30 receives the electromagnetic wave component of 160 kHz generated in the transmission side coil 20u at this time (S21), and determines the minimum value of the reception level V160u. It is stored (S22).

That is, the reception level V1 measured up to immediately before
Minimum of 60u and reception level V16 measured this time
The smaller value of 0u is stored as the minimum value of the reception level V160u. When the reception level V160u is measured first, that value is set to the reception level V160u.
Is stored as the minimum value of. Then, when a value larger than the minimum value is detected (S23), the coin 70 keeps moving away from the coin detection area thereafter, and a value gradually larger than the minimum value is detected. Therefore, the reception level V160u The operation of detecting the minimum value of is stopped, and the current minimum value is confirmed as the minimum value.

At this time, the CPU 60 gives an instruction to the signal generating circuit 10 so that a signal of 10 kHz flows to the transmitting side coil 20, and at this time, the receiving side coil 30.
Of the reception level V10 is measured, and the reception level V10 is stored as the minimum value of the reception level V10 (S24).
That is, since the transmission side coils 20 and 20u are present at the same position in the moving direction of the coin 70, the reception level V10 detected when the reception level V160u becomes the minimum value is the minimum value of the reception level V10. is there. Next, the CPU 60 commands the signal generation circuit 10 to flow a signal of 160 kHz to the transmission side coil 20, at which time the reception level V160 of the reception side coil 30 is measured, and the reception level V160 is measured. It is stored as the minimum value of V160 (S25).

The reception level V1 thus detected
The type of coin is determined according to the minimum value of 60, V160u, and V10. Reception levels V160, V160u, V
Data associating each minimum value of 10 with the type of coin is stored in the memory 61 in advance.

According to the above-described embodiment, the second transmitting coil 20u is provided near the upper end portion of the coin 70 in addition to the first transmitting coil 20 provided at the center of the coin 70. Even if coins are made of almost the same material, if the diameters are slightly different, the difference in diameter can be grasped.

FIG. 5 shows a coin 70 in the above embodiment.
FIG. 7 is an operation explanatory diagram when determining a difference in material and diameter of the, and is a diagram showing an input signal of the A / D conversion circuit 55.

In FIG. 5, when there is no shielding (when the coin 70 is not in the coin detection area), 160 kH
The reception level V160 of z is 100%, 160 kHz
The signal z is flowing to the transmitting coil 20. At time t1, the reception level V160 of 160 kHz is reduced to 75% of the value at the time of non-shielding, a signal of 10 kHz flows to the transmission side coil 20, and at time t2, the reception level V160 and the reception level V10 are compared, and reception is performed. Since the level V160 is lower than the reception level V10, there is a possibility that it is a 500-yen coin.
The signal of z flows to the transmission side coil 20u, the reception level V160u is detected, and at time t3, the reception level V16u is detected.
0u becomes the minimum (this detection level is the reception level V16
0 um), at time t4, a signal of 10 kHz flows to the transmitting coil 20, the reception level V10 thereof is detected (this detection level is the receiving level V10m), and at time t5, a signal of 160 kHz is transmitted to the transmitting coil. 20, the reception level V160 is detected (this detection level is the reception level V160m).

By the way, returning to the flowchart shown in FIG. 4, in S12, if the receiving level V160 is not less than the receiving level V10, the inserted coin 70 is a coin other than 500 yen. It is easy to discriminate the coin even if the judgment is made, and the diameter of the coin is not judged. That is, the reception level V10 is measured (S41), and the minimum value of the reception level V10 is stored (S42). When a value larger than the minimum value is detected (S43), the coin 70
Is moving away from the detection area, and a value gradually larger than the minimum value will be detected. Therefore, the operation of detecting the minimum value of the reception level V10 is stopped, and the current minimum value is determined as the minimum value. . At this time, the reception level V160 is measured and the reception level V160 is stored as the minimum value of the reception level V160 (S4).
4). The coin type is determined according to only the two minimum values of the reception levels V160 and V10 detected in this way (S50). In S41 to S50, since the operation of detecting the difference in the diameter of the coin 70 is omitted,
Discrimination of coins other than the 500-yen coin can be performed quickly.

FIG. 6 shows a coin 70 in the above embodiment.
FIG. 6 is an operation explanatory diagram when only the material of the
6 is a diagram showing an input signal of a conversion circuit 55. FIG.

In FIG. 6, at time t11, 160 kHz
The reception level V160 of z is reduced to 75% of the value without shielding, and at this time, the signal of 10 kHz is transmitted to the transmitter coil 20.
Then, at time t12, the reception level V160 and the reception level V10 are compared with each other. Since the reception level V160 is larger than the reception level V10, it can be determined that a coin other than 500 yen has been inserted. Since the coin can be discriminated without checking the reception level V1
60u is not detected. At time t13, the reception level V10
Is minimized (this detection level is the reception level V10m), and at time t14, the reception level V160 is detected (this detection level is the reception level V160m).

The order of the combination of the signal and the transmitting side coil for supplying this signal and the order of the combination of the frequencies of the supplied signals may be other than the above, and the frequency to be used may be other than the above.

In the above embodiment, when the receiving level V160 is smaller than the receiving level V10, the size of the diameter of the coin 70 is discriminated, and when the receiving level V160 is the receiving level V10 or less, the coin 70 Although the size of the diameter is not discriminated, the size of the diameter of the coin 70 may be discriminated only when other conditions are satisfied. For example, the diameter of the coin 70 is determined only when the condition that the reception level V80 by the signal of 80 kHz is smaller than the reception level V10 or the condition that the reception level V80 is the reception level V10 or less is satisfied. You may

Further, in the above embodiment, only the currents having the same frequency are passed through the transmitting coil 20u, but the currents having two frequencies may be passed through the transmitting coil 20u. Even in this way, the difference in the shape of the coin can be detected.

In the above embodiment, the number of receiving coils is 1.
Although only one coil is provided, two reception side coils may be provided instead. That is, the receiving side coil may be provided in the vicinity of the first transmitting side coil, and another receiving side coil may be provided in the vicinity of the second transmitting side coil.

[0038]

According to the present invention, it is possible to discriminate a difference in diameter between coins made of almost the same material if the diameters are slightly different from each other, and to discriminate a predetermined coin quickly. It has the effect of being able to.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a specific example of a signal generation circuit 10 in the above embodiment.

FIG. 3 is an explanatory diagram of a basic operation of the above embodiment.

FIG. 4 is a flowchart showing the operation of the above embodiment.

FIG. 5 is an explanatory diagram of the operation of the above embodiment.

FIG. 6 is an explanatory diagram of the operation of the above embodiment.

[Explanation of symbols]

 10 ... Signal generating circuit, 11 ... High frequency signal generating circuit, 12 ... Low frequency signal generating circuit, 20 ... 1st transmission side coil, 20u ... 2nd transmission side coil, 30 ... Receiving side coil, 60 ... CPU.

Claims (4)

[Claims] 1. A receiving side coil is provided at a position where an electric current having a predetermined frequency is passed through the transmitting side coil and receives an electromagnetic field component from the transmitting side coil through a coin passage. In a coin sensor for determining the type of coin according to data, one of the above-mentioned transmitting side coils, which is located approximately in the center of the coin when the coin rolls, One of the transmitting side coils, and a second transmitting side coil installed close to the first transmitting side coil, and when the received data satisfies a predetermined condition, the first transmitting side coil To the first transmitting coil, but not to the second transmitting coil, and when the received data does not satisfy the predetermined condition, the first transmitting coil is supplied with the signal. Supply Both coin sensor and supplying a signal also to the second transmission coil. 2. The predetermined condition according to claim 1, wherein a high frequency signal and a low frequency signal are supplied to the first transmission side coil, and a level of received data by the high frequency signal is a level of the predetermined received data. A coin sensor characterized in that the condition is higher than that. 3. The coin sensor according to claim 1, wherein one or two receiving coils are provided. 4. The coin sensor according to claim 1, wherein the core of the second transmitting coil is shorter than the core of the first transmitting coil.