JPS6327996A - Coin selector - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to public telephones, various vending machines, etc.
The present invention relates to a coin sorting device used to determine the authenticity and type of coins inserted.

[Conventional technology]

Conventionally, this type of device is disclosed in, for example, the published patent publication 1973.
There is one described in No. 500263 of 2008. This sorting is done by using oscillating magnetic fields of two frequencies, high and low, at a low frequency such that the generated magnetic flux passes through the coins to be sorted. On the other hand, the material is to be sorted by the lower oscillating magnetic field, and the thickness and diameter of the coil for material sorting are smaller than the diameter of the smallest diameter coin to be sorted. An oval coil whose major diameter is υ larger than the diameter of the above-mentioned minimum diameter coin, and the diameter is
Sorting signals can be obtained independently for each characteristic of thickness and material.

[Problem that the invention seeks to solve]

The above-mentioned conventional cargo sorting device has the advantage of being able to obtain independent outputs for each sorting element, but on the other hand, only the coil for diameter sorting is used for the diameter, and the coil for thickness sorting is used for the thickness and material. In this case, the output change is largest near the center of the coil where the magnetic flux is concentrated, and the accuracy is highest near the center. If there are two types of coins made of the same material but with slightly different diameters,
When a small diameter coin is wrapped with different materials and matched with a large diameter coin, there is a high probability that the two types of coins will be mistakenly judged to be the same coin.

[Means for solving problems]

The coin sorting device of the present invention includes a first oscillating coil that forms an oscillating magnetic field with a frequency that is closer to the coin, and a receiving coil that are arranged opposite to each other on the coin non-contact surface side and the contact surface side of the inclined coin passage. The above t on the coin contact surface side or non-contact surface side.
A second oscillation coil is arranged at a predetermined distance from the oscillation coil of J1 in the coin rolling direction, and is formed into a ring shape corresponding to the outer periphery of a specific type of coin and forms an oscillation magnetic field of a lower frequency. be. The coin sorting device of the present invention further includes means for detecting the maximum change in impedance of the first oscillation coil and the reception coil as the coin passes, and a means for detecting the maximum change in impedance of the first and second oscillation coils when the impedance changes of the first and second oscillation coils match. It is provided with means for detecting the amount of change in impedance and determining means for determining the authenticity and type of the coin from the detection results of each of these detecting means.

[Effect]

The maximum impedance change of the first oscillating coil when the coin passes changes depending on the thickness of the coin, and the maximum impedance change of the receiving coil changes depending on the material and thickness.
The material and thickness are determined from these impedance changes. Furthermore, when a rolling coin passes through the detection surfaces of the first and second oscillation coils that are arranged apart in the rolling direction, its impedance changes depending on the area covered by each detection surface. However, depending on the size of the diameter of the coin, a difference occurs in the timing at which the impedance changes of the two coincide. Therefore, the diameter is determined based on the amount of impedance change when they match. The impedance change of the first oscillation coil is also affected by the material, and in the end, unless the coin has a certain material, thickness, and diameter, the change in impedance of both coils for material and thickness sorting will match. This causes a deviation in the amount of change in impedance. Furthermore, the impedance change of the ring-shaped second oscillation coil varies depending on the material of the outer peripheral portion of the coil corresponding to the ring-shaped detection surface, even for coins having the same diameter.

In other words, there is a difference between an original coin with the same diameter and a coin with a smaller diameter wrapped around a different material to have the same diameter (hereinafter such pseudo coins are referred to as headband coins). Since the material of the outer circumferential portion of the oscillation coil on the detection surface is different, a difference occurs in the impedance change.

〔Example〕

FIG. 1 is a block diagram showing one embodiment of the present invention, FIG. 2 is a side view of the coin passage 1 seen from above in FIG. 1, and FIGS. 1--■ sectional view and IV-IV sectional view of the figure.

A first oscillating magnetic field that forms an oscillating magnetic field of a higher frequency (but within a lower frequency band where the generated magnetic flux passes through the coin; in this example, 20 KHz) on the non-contact side of the coin 2 of the inclined coin passage 1. A receiving coil A2 is arranged on the contact surface side of the coin 2 opposite to the oscillating coil A1, and a receiving coil A2 is further arranged on the contact surface side of the coin with a predetermined distance from the receiving coil A2 in the rolling direction of the coin. A second oscillation coil B1 is arranged to form an oscillation magnetic field of a lower frequency (8 KH in this embodiment).

In this embodiment, the positional relationship between the first oscillating coil A1, the receiving coil A2, and the second oscillating coil B1 is such that the former is placed above and the latter is placed below along the rolling direction of the coin. , it is also possible to reverse the procedure in relation to the signal processing procedure described later.

Further, a second oscillation coil B1 was placed on the coin contacting surface side. This is because it allows for a wider output fluctuation range and enables more accurate judgment, but it is also possible to place it on the coin non-contact surface side by providing a means to amplify the output signal. It is.

Near i#1. The distance d between A2 and coil B1 is such that when a coin is located at the center of coil AI, A2 and coil B1, the outer periphery is between coil A1 and coil B1.
For any of these, the detection range is set, preferably within a range in which a large output change can be obtained. This varies depending on the height of each coil from the bottom of the coin passage, and is also influenced by the shape of each coil. In this embodiment, the diameter of the coins to be sorted is assumed to be 16 to 33nx, and the outer diameter of the first oscillating coil A1 and receiving coil A2 is 14.0nx. w, the diameter of the detection range is 1On+, and the diameter of the range where a particularly large output change can be obtained is 6
A coil No. 111 is placed at a height of hl"9jtl from the bottom of the coin passage, with an interval of d=29mm, and the second oscillation coil B1 has an outer diameter of 36uI and an inner diameter of 21.5.
ms coil.

=12-5fi height. The detection range of the second oscillation coil B1 is a band-shaped portion between the inner diameter and the outer diameter.

10 to 30 are senna circuits connected to each coil,
11.31 is an oscillation circuit, 13, 21.33 is an amplifier circuit,
12.14, 22.32.34 are rectifier circuits, respectively. Reference numeral 40 denotes a temperature sensor circuit for temperature compensation, and based on this output, the detected data is temperature-corrected.

Next, the principle of detecting the characteristics of coin material, thickness, and diameter will be explained using FIGS. 5 and 6.

First, as the coin 2 rolls as shown in FIG. 5, the coil A1. When passing between the detection surfaces of A2, the coil A1
The impedance changes depending on the material of the coin and the distance from the detection surface of the coil A1 to the coin surface, in other words, the thickness of the coin. Due to this impedance change, the output oscillation @ of the oscillation circuit 11 changes, and the rectified output voltage Vh
1 also changes as shown in FIG. 6 (-). This minimum level is defined as the thickness characteristic level.

On the other hand, the alternating magnetic field excited by the coil A1 is applied to the coin 2.
An alternating voltage is excited in the coil A2 through the coil A2. The amplitude of this excited AC voltage varies depending on the material of the coin, but
Since the oscillating magnetic field generated by the primary coil AIK changes depending on the thickness of the coin as described above, it is also affected by the thickness. Therefore, after amplifying the AC voltage with , the rectified output voltage '/A! The minimum level (FIG. 6(b)) is taken as the material thickness characteristic level.

Note that the output changes depending on the material, as shown in Figure 7, the alternating magnetic field with a relatively low frequency is more noticeable, but the difference between the oscillating coil A1 side (Figure 7 (a)) and the receiving coil A2 side (Figure 7 (a))
There is a slight difference in the way it appears compared to Fig. 7(b)). In the same figure, curve I is iron, ■ is stainless steel, ■ is cupronickel, and ■
indicates phosphorus back copper, ■ indicates brass, and ■ indicates nickel.

Furthermore, when the rolling coin 2 passes through the detection surfaces of the first and second oscillation coils, the output varies depending on the area covered by each detection surface, but the impedance of both depends on the diameter of the coin. A timing error occurs when the changes coincide. For this reason, in this embodiment, coil A1
The level VD when the output voltage VAI of the coil B1 matches the output voltage 'f'll of the coil B1 is defined as the diameter characteristic level.

Further, the shape of the second oscillation coil B1 is determined according to the outer diameter of a specific type of coin, so that the excited alternating magnetic field is concentrated on the outer periphery of the coin. As a result, the voltage vm, which is the amplified and rectified output of the coil B1, changes depending on the material of the outer circumference of the coin.

The minimum level of this output voltage v1 is defined as the outer peripheral material characteristic level. By comparing the above-mentioned material thickness characteristics with predetermined characteristic values, it is possible to select coins that are made of the same material near the hard center but different materials on the outer periphery. In other words, it is possible to prevent headband coins from being mistaken for genuine coins.

In addition, in this embodiment, the output voltage V is further amplified by amplifying the output of the oscillation circuit 11 so that changes due to thickness can be more clearly captured. The minimum level of 1 is defined as a specific coin thickness level, and is used to determine whether a small-diameter coin has been crushed to appear as a large-diameter coin.

In FIG. 1, 50 is a control unit equipped with a processor unit (hereinafter abbreviated as CPU) 51 such as a well-known microprocessor.
only memory: read-only memory) 5
R as appropriate according to the program stored in advance in 2A.
AM (random access memory)
While accessing a predetermined area of the 52B (readable/writable memory), each part is controlled to detect each characteristic data of the inserted coin, and
programmable read only me
mory: electrically programmable ROM) 52C
The authenticity and type of coins are determined from the data stored in K, and the accumulation trajectory of K determined to be genuine coins is accumulated. This embodiment is a nine example in which a coin sorting unit)K of a public telephone is applied.When a specie coin is accumulated, a signal indicating the type of coin is sent to the main CPU of the telephone unit via a transmission line 6o. (not shown)

In addition, 53 is an AD converter for converting the output voltage of each sensor into digital data and taking in it, and 54 is its channel control circuit. Reference numeral 55 denotes a feeding detection circuit, which connects each coil person 1 in the coin track 1. A2. It is composed of a photocoupler etc. placed above B1,
This detects whether a coin has been inserted. The passage detection circuit 56 is also constructed of a photocoupler or the like, and is used to confirm that the coin has entered the accumulation orbit. Reference numeral 57 is a circuit that drives a sorting lever to guide the inserted coin to the accumulation trajectory.If the inserted coin is determined to be a fake coin, the sorting lever is not driven and the coin is automatically returned to the return slot. Ru. A sensor power supply control circuit 58 controls the power supply of each sensor circuit 10 to 40.

Next, this sorting operation will be explained in detail with reference to FIGS. 8 and 9.

In FIG. 9, the CPU 51 performs initial settings (initialization) (step 101) and then waits for coins to be inserted. When the insertion detection circuit 55 detects that a coin has been inserted (step 102), the power to each sensor is turned on (step 103), and the coin percentage is determined.

Measurement is performed (step 104).

In this coin characteristic measurement routine, the output "ml + '/Am + vMl" of each sensor DO path 10 to 30 is periodically A/D converted and taken in, and from this conversion data, the above-mentioned material primary characteristics, material 2 The coin characteristic measurement routine program will be explained below with reference to FIG. 9.

In FIG. 9, when the execution of the program shifts to the coin characteristic measurement routine, the CPU 51 clears all areas of the peak hold memory (PHM) and cross point memory (XPM) 7) provided in a predetermined area of the RAM 52B (step 201), AD of sensor circuit output
Conversion is performed (step 202). Initially, vAI + “A” is used to detect the characteristic level of material and thickness.
AD conversion is performed by selecting only the AI and vl channels. Next, after confirming that each sensor circuit is working normally without any abnormalities such as fresh green leaves by confirming that a certain output level is obtained (step 203), the output voltage Vh1+ of the AD-converted sensor circuit 10 is confirmed. When the detected value of Vl At does not reach the peak value (step 204), the
4.1 data to the first peak hold memory (PHM)
1), the data of VA 1 is stored in the second peak hold memory (PHM2) (step 20
5) Similarly, if the detected value of the output voltage vl of the sensor circuit 20 does not reach the peak value (step 206), the "A"
ffi data to third peak hold memory (P) 1M
3) (step 207). vAl + VA
Unless both peak values of I are detected! 11 (step 208), Vtt (vAAl) and van are similarly taken in repeatedly, and the contents of the peak hold memory are completely updated until the peak value is detected.

After the detection of the peak values of vAl, v, * is completed, step 208), CP (J51 is the diameter characteristic level ■).

is detected (step 209), VAI and Vll
1.XPM1.
2 (step 211), and its values are sequentially updated. Then, when VAI > Vat (step 210), the average value
seek. This detected value 'l'AI + vml is stored in the first and second cross point memories XPM1.
It is stored in XPM2 (step 112). Similarly, this time "AI>" 11 and 'atsu nine relevant detected value'/At +
”11 Kara, find its average value X! (Step 213
), and these X-ri and X! Take the average value of
This is set as a VD (step 214).

On the other hand, O'Vll 1vlA f is stored in the fourth and fifth peak hold memories PHM4 and PHM5 until the peak value of Vml is detected (step 215).
) Update and store the value (step 216).

When all the data corresponding to the five types of characteristics have been detected in this way (step 217), next CPt
J51 performs temperature correction on each of the above characteristic data (step 218). This depends on the temperature characteristics of each sensor circuit.
i. Since the analog signal input to the AD converter 53 changes depending on the ambient temperature, this is done in order to compensate for this influence, and each characteristic data obtained as described above is It is converted into a value at the reference temperature according to the detected output voltage Ttmp. To this end, in this embodiment, a predetermined area of the lPROM52C is divided in advance into blocks for each characteristic of material thickness characteristics, diameter characteristics, outer material characteristics, thickness characteristics, and specific coin thickness characteristics. Corresponding correction data is stored in a form that associates a specific address with a specific temperature.

Therefore, when a certain characteristic data is obtained for a certain characteristic, for example, a material thickness characteristic, and on the other hand, data indicating the ambient temperature at that time is obtained by AD converting the output of the temperature sensor circuit 40, the material thickness One complete address data is created by adding the above temperature data as a lower bit to the block address indicating the block storing the temperature correction data regarding the characteristics.
Specify a predetermined area of 2C (ADD indicates the address bus for this purpose). Then, since data indicating that a predetermined value should be subtracted or added is stored there, it is read out and corrections are made according to its contents. This is performed for each characteristic data to obtain corrected data. Note that such a temperature correction method is described in the applicant's separate application II (Japanese Patent Application Laid-Open No. 60-2622).
93 Publication) for details.

After completing the measurement of the coin characteristics as described above (step 104 in FIG. 8), the CPtJ 51 turns off the sensor power source (step 105), and then sequentially determines whether the coin is dressed properly for each characteristic (steps 106 to 110). This is done as follows. That is, in this embodiment, the EFROM
52 C is divided into blocks for each of the four types of characteristics, and the values of each characteristic data are allowed or not, and if the coin is a type of coin with a pinch, and if the coin is 100 yen, it is within the acceptable range as a genuine coin. Data indicating whether or not a specific characteristic data value is stored in a form that corresponds to a specific address. More specifically, this data includes, for example, the top 3
The bits correspond to coins of 100 yen, 50 yen, and 10 yen, respectively, and if the characteristic data value corresponding to that address is within the allowable range for a 100 yen coin, for example, the most significant bit is set to ``0''. '', and if it is acceptable as a genuine coin of 50 yen or 10 yen, the second and third bits are respectively set to rOJ. Other bits are set to "1".

Therefore, when certain characteristic data is obtained for a certain characteristic, for example, material thickness characteristic, the above characteristic data is added as a lower bit to the block address indicating the block that stores the acceptability data for the material thickness characteristic. 1
By creating two complete address data,
Specify a predetermined area of the EPROM 52C and read the data.

When each of the five pieces of data is read in this way,
Next, the CPU 51 comprehensively judges these five data and determines the type of the coin (step 111).
. In this embodiment, this determination is specifically performed as follows. In other words, the logical sum of the five data bits is calculated. For example, in the case of a genuine coin of 100 yen, all of the above four data sets have a "0" bit at the top, so the result of taking the logical sum is that the top bit is "0".
”. Therefore, conversely, if the most significant bit is "0", it can be seen that the coin is acceptable as a 100 yen coin. Similarly, it can be seen that if the second bit is "0", it can be accepted as a 50 yen coin, and if the third bit is "0", it can be accepted as a 10 yen coin. Note that such a determination method is detailed in Ratio B (Japanese Unexamined Patent Publication No. 60-262292) published by the present applicant.

In this way, if only one of the top three bits corresponding to each coin type is "0", it is determined that the coin is a genuine coin of the type corresponding to the bit position (step 112). In that case, the CPU 51 immediately operates the lever for distribution (
Step 113), after confirming that the coin has headed towards the accumulation trajectory (Step 114), the sorter restores the lever (Step 115) and outputs data indicating the type of the accumulated coin to the main processor ( Step 116
). As a result, the main processor can grasp the accumulated amount, display this on the display, and display the accumulated amount when the call charge obtained by multiplying the charging frequency by the unit call charge exceeds this accumulated amount. You will be able to forcefully disconnect a call.

If there is no bit "0" or two or more bits in the logically added data of the five data, it is determined to be a pseudo currency (step 112). In that case, the lever for sorting is not operated and the coins are automatically returned.

〔Effect of the invention〕

As explained above, according to the present invention, as a result of making a comprehensive judgment by correlating the sorting factors of material, thickness, and diameter, the probability of missorting is reduced so that headband coins are judged as genuine coins. can be done.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a side view of the coin passage seen from above in FIG. 1, FIGS. 3 and 4 are cross-sectional views, and FIG. Figure 5 is a diagram showing how the bar is rolling, Figure 6 is a diagram showing each output at that time, Figure 7 is a diagram showing the frequency dependence of material characteristic output, and Figure 8 is a diagram showing the frequency dependence of material characteristic output.
9 and 9 are flowcharts. DESCRIPTION OF SYMBOLS 1... Coin passage, 2... Coin, 5o... Control unit, 51... Processor unit, 52C... Fist/EPROM, A1/φ... First oscillation coil, A20
00. Receiving coil, B1. ...Second oscillation coil. Patent Applicant Tamura Electric Manufacturing Co., Ltd. Agent Masaki Yamakawa (and 2 others) Figure 2 Figure 3 Figure 4 Figure 7 Junpisanqfu

Claims (1)

[Claims] In a coin sorting device that determines the authenticity and type of coins by oscillating magnetic fields of two frequencies, high and low, in a low frequency band where the generated magnetic flux passes through the coin, A first oscillation coil that forms an oscillation magnetic field with a higher frequency on the contact surface side and a reception coil are arranged facing each other, and a coin rolling from the first oscillation coil is placed on the coin contact surface side or the non-contact surface side. A second oscillation coil is arranged at a predetermined distance in the direction, and is formed in a ring shape corresponding to the outer periphery of a specific type of coin, and generates an oscillating magnetic field of a lower frequency. means for detecting the maximum value of each impedance change of the oscillating coil and the receiving coil; means for detecting the amount of impedance change when the impedance changes of the first and second oscillating coils match; and detection of these detecting means. 1. A coin sorting device comprising means for determining the authenticity and type of a coin from the results.