JPH0795350B2 - Automatic adjustment device for bill sensitivity of bill validator - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bill validator used in, for example, an automatic vending machine or a money changer, and more particularly to an automatic identification sensitivity adjusting device.

2. Description of the Related Art Generally, in a bill validator, dimensions of bills to be identified,
The authenticity of the inserted bill is identified by detecting the thickness and the magnetic susceptibility of the magnetic substance contained in the printing ink. However,
The density of the printing ink varies slightly depending on the time when the banknote was manufactured, and changes rapidly with use. Therefore, the magnetic susceptibility of the magnetic substance contained in the printing ink also varies depending on the time. is there.

Therefore, in the conventional bill validator, the genuine bill recognition rate is remarkably reduced as the years of use pass.

In addition, there was a method in which the magnetic susceptibility range that can be recognized as a genuine note, that is, the identification sensitivity can be adjusted, and the magnetic susceptibility range is readjusted once every several years, but at this time, the bill validator has already been widely distributed in the market. Therefore, the readjustment work is very time-consuming and time-consuming.

In order to make up for this drawback, as described in Japanese Patent Laid-Open No. 59-105190, "Automatic adjustment device for identification sensitivity of bill validator", the magnetic susceptibility of each individual bill is different from the total number of genuine bills. When the ratio of the number of genuine bills having a value is obtained and the ratio reaches a specific value that is considered to occupy the majority of the total number of genuine bills, the magnetic susceptibility is newly set as the center of the genuine bill. By determining the magnetic susceptibility range that can be recognized as, it is possible to automatically adjust the discrimination sensitivity of the bill validator, prevent the reduction of the true bill recognition rate due to the years of use of the bill validator, and at the same time, determine the magnetic susceptibility that can be certified as a true bill. It was proposed that the readjustment work of the range is unnecessary.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the above-described device, when a genuine bill having a specific magnetic susceptibility is biased into the device, it is erroneously regarded as a genuine bill with the magnetic susceptibility as the center. The range of magnetic susceptibility that can be recognized was determined, and on the contrary, there was a risk of causing a decrease in the genuine bill recognition rate thereafter.

The present invention is to solve the above problems, and even if a genuine bill having a specific magnetic susceptibility is biasedly inserted, it does not mistakenly determine the magnetic susceptibility range that can be recognized as a genuine bill. An automatic sensitivity adjustment device is provided.

Means for Solving the Problems In order to solve the above problems, the identification sensitivity automatic adjustment device of the bill validator of the present invention is a magnetic sensor for detecting a magnetic susceptibility of a magnetic material of a printing unit of a deposited bill, and the magnetic sensor. By the A / D converter that converts the magnetic susceptibility detected by to a digital signal, and the magnetic susceptibility converted into a digital signal by the A / D converter, whether or not it is within a magnetic susceptibility range that can be recognized as a genuine note. A discriminating means for discriminating, a counter for calculating the total number of genuine bills, and a number of genuine bills having the magnetic susceptibility value for each of a plurality of magnetic susceptibility values within a magnetic susceptibility range that can be recognized as a genuine bill. A plurality of counter groups, a divider that divides the count value of the plurality of counter groups by the total number of genuine bills, and the total number of genuine bills, when reaching a certain constant value, the standard deviation of the magnetic susceptibility and When the calculator that calculates the average value and the standard deviation reach a value within a specific range, the average value With a new magnetic susceptibility as a center, a determining unit for determining a magnetic susceptibility range that can be recognized as a genuine bill is provided.

Effect The present invention, with the above-described configuration, calculates the standard deviation and average value of the magnetic susceptibility when the total number of genuine bills reaches a certain fixed value,
Only when the standard deviation reaches a value within a specific range, the magnetic susceptibility closest to the average value is newly set as the center, and the magnetic susceptibility range that can be recognized as a genuine bill is determined. Even if a genuine bill with a certain value is biasedly inserted, the identification sensitivity is automatically adjusted without deciding the magnetic susceptibility range that can be mistakenly recognized as a genuine bill, and the genuine bill recognition rate is reduced due to the years of use of the bill validator. In addition to the prevention, the readjustment work of the magnetic susceptibility range that can be recognized as a genuine note is unnecessary.

Embodiment An automatic identification sensitivity adjusting apparatus for a bill validator according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of an automatic discrimination sensitivity adjusting device of a bill validator according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a magnetic sensor, which detects the magnetic susceptibility of a magnetic substance contained in the printing ink of the inserted bill and outputs an analog signal output 1a corresponding to the magnetic susceptibility. 2 is an A / D converter,
The analog signal output 1a of the magnetic sensor 1 is converted into a digital signal output 2a and output. 3 is a discrimination means, which is the A /
The digital signal output 2a of the D converter 2 is received, and it is determined whether or not it is within the magnetic susceptibility range that can be recognized as a genuine note. If it is within the range that can be recognized as a genuine bill, the genuine bill signal 3a and the genuine bill count pulse 3b are output, and the magnetic susceptibility value x _m is output.
N (where n is any integer) magnetic susceptibility values (that is, x ₁ , x ₂ , ...
_m , ..., X _n-1 , x _n ) which magnetic susceptibility value has been discriminated, and a susceptibility-specific genuine bill count pulse Si corresponding to each is output. Where Si is S ₁ , S ₂ ,…, S _m ,…, S
The output indicates one of _n-1 and S _n .

If it is not within the range that can be recognized as a genuine bill, the counterfeit bill signal 3c
Is output. A bill storage mechanism 4 receives the true bill signal 3a from the discrimination means 3 and stores the inserted bill. Further, the genuine ticket signal 3a allows the vending machine to perform a selling operation and the money changing machine to perform a money changing operation. Reference numeral 5 denotes a bill returning mechanism, which receives the counterfeit bill signal 3c from the discrimination means 3 and returns the inserted bill.

Reference numeral 6 denotes a total true bill number counter, which receives the true bill count pulse 3b from the discriminating means 3, counts the total true bill number Ns, and outputs a count value. Further, when the total number of genuine bills Ns reaches a certain value, the count-up signal 6a is output. Here, the certain constant value is a sufficiently large value for examining the distribution of the magnetic susceptibility of the magnetic material contained in the printing ink of the banknotes distributed in the market. C ₁ , C ₂ , ..., C _m , ..., C _n−1 , C _n are susceptibility-value-based genuine bill number counters, and susceptibility-based genuine bill count pulses S ₁ and S of the discriminating means 3 ₂ , ..., S _m , ..., S _n-1 , S _n , and the corresponding susceptibility-value-specific genuine sheet numbers N ₁ , N ₂ , ..., N _m , ..., N _n-1 , N _n
Is counted and the count value is output.

Reference numeral 7 denotes a divider which receives the count-up signal 6a from the total genuine bill number counter 6 and sequentially receives the susceptibility-specific genuine bill number counter Ci.
Is calculated by dividing the number of genuine bills by magnetic susceptibility Ni from the total number of true bills Ns from the total number of true bill counters 6 into the division result Qi (= Ni / N
s) is output to the average value calculator 8 and the standard deviation calculator 9.
Here, i indicates any one of 1, 2, ..., M, n−1, n. The average value calculator 8 receives the division result Qi from the divider 7, calculates the average value according to the following equation (1), and outputs the calculation result to the standard deviation calculator 9 and the determining means 10. Output.

The standard deviation calculator 9 is a division result from the divider 7.
Upon receiving Qi and the average value from the average value calculator 8, the standard deviation δ is calculated by the following equation (2), and the calculation result is output from the determining means 10.

The determining means 10 receives the average value from the average value calculator 8 and the standard deviation δ from the standard deviation calculator 9,
The standard deviation δ corresponds to the distribution of the magnetic susceptibility of the magnetic substance contained in the printing ink of the banknotes in the market, which is considered to be valid. Only when the value within a specific range is reached, the magnetic susceptibility value closest to the average value is newly determined, the susceptibility range that can be recognized as a genuine bill is determined, and the determination signal 10a is output.
It functions to control the discrimination means 3.

The operation of the automatic discrimination sensitivity adjusting device of the bill discriminating machine configured as described above will be described below with reference to FIGS. 2 and 3.

First, the magnetic susceptibility of the magnetic substance contained in the printing ink of the banknotes circulating in the market at a certain time is from x ₁ to x _n with the magnetic susceptibility value x _m as the center, as shown in A of FIG. It is distributed in the width, and the distribution is a normal distribution. When the number of years has passed, the magnetic susceptibility of banknotes distributed in the market changes as shown in B of FIG. 2 due to the difference in the manufacturing time, but the distribution width is almost constant.

Therefore, in order to detect the difference due to the manufacturing time, this device operates as follows, as shown in FIG.

Here, the total genuine bill number counter 6 counts and stores the total genuine bill number Ns of the inserted bills so far, and the magnetic susceptibility value-based genuine bill number counter group C ₁ , C ₂ , ..., C _m , ..., C _n-1 , C _n are the numbers of genuine bills by magnetic susceptibility value N ₁ , N ₂ , ..., N _m , ..., N _n-1 , N _n, which are counted and stored. And

When a bill is inserted into the bill validator (step 1), the magnetic sensor 1 outputs an analog signal 1a corresponding to the magnetic susceptibility, and the A / D converter 2 converts the digital signal 2a (ste).
p2). When the inserted bill is a counterfeit bill (step 3), the discrimination means 3 outputs a counterfeit bill signal 3c, and the bill return mechanism 5 returns the inserted bill (step 4).

When the inserted bill is a genuine bill (step 5), the genuine bill signal 3a is output from the discrimination means 3 and the inserted bill is stored by the bill storing mechanism 4 (step 6). And genuine bill count pulse 3
When b is output, the total genuine bill counter 6 counts the total genuine bill number Ns (step 7). Further, if the magnetic susceptibility value of the inserted bill is Xa, the corresponding susceptibility value-specific genuine note count pulse Sa is output, and the corresponding susceptibility-value-specific genuine note number counter Ca is the susceptibility-specific genuine note. Count the number Na (step 8).

Next, when the number of genuine banknotes Ns reaches a certain value (step
9), the total genuine bill counter 6 outputs a count-up signal 6a (step 10). Here, the certain constant value is a sufficiently large value for examining the distribution of the magnetic susceptibility of the magnetic substance contained in the printing ink of the banknote. Next, the divider 8 receives the count-up signal 6a, sequentially performs division (step 11), and outputs the division result Qi (Ni / Ns). And the average value calculator 8
Calculates the average value according to equation (1) (st
ep12), output the average value. Then, the standard deviation calculator 9 calculates the standard deviation δ according to the equation (2) (step 13) and outputs the standard deviation δ. Next, the decision means 10
Is an average value and a standard deviation δ, and the standard deviation δ corresponds to the distribution of the magnetic susceptibility of the magnetic material contained in the printing ink of the banknotes in the market, which is considered to be valid. When the value within a specific range is reached (step 14), the magnetic susceptibility value closest to the average value is newly set as the center to determine the magnetic susceptibility range that can be recognized as a genuine note, and the determination signal 10a is output to determine the value. The means 3 is controlled (step 15). Then, the deciding means 10 outputs a clear signal 10b, and the total genuine bill number counter 6 and the magnetic susceptibility value-dependent genuine bill number counter groups C ₁ , C ₂ , ..., C _m , ..., C _{n- 1} and C _n are all cleared (step 16), and the total genuine bill number counter 6 and the magnetic susceptibility value-based genuine bill number counters C ₁ , C ₂ , ..., C _m , ..., C _n-1 , C _n are newly added. Start counting.

According to the automatic discrimination sensitivity adjusting device of the bill validator shown in the embodiment, the magnetic sensor 1 for detecting the magnetic susceptibility of the magnetic material of the printing portion of the inserted bill, and the magnetic susceptibility detected by the magnetic sensor 1 are converted into digital signals. A / D converter 2 for converting and the A
A discriminating unit 3 for discriminating whether or not the magnetic susceptibility converted into a digital signal by the / D converter 2 is within a magnetic susceptibility range that can be recognized as a genuine note, and a total true number for counting the total number of genuine bills of inserted bills. A bill number counter 6 and a plurality of genuine bill number counters for each magnetic susceptibility value for counting the number of genuine bills having the magnetic susceptibility value for each of a plurality of magnetic susceptibility values within a magnetic susceptibility range that can be recognized as a genuine bill. C ₁ , C ₂ ,…, C _m ,…, C _n-1 , C _n
, A divider 7 for dividing the count value of the plurality of counter groups C ₁ , C ₂ , ..., C _m , ..., C _n-1 , C _{n by} the total number of genuine bills, and the total number of genuine bills,
When a certain value is reached, an average value calculator 8 that calculates the average value of the magnetic susceptibility, a standard deviation calculator 9 that calculates the standard deviation of the magnetic susceptibility, and the standard deviation reaches a value within a specific range. In this case, the deciding means 10 for deciding the range of the magnetic susceptibility that can be recognized as a genuine bill by newly centering the magnetic susceptibility value closest to the average value
With the above configuration, when the total number of genuine bills reaches a certain fixed value, the standard deviation and average value of the magnetic susceptibility are calculated, and the standard deviation reaches a value within a specific range. Only in the case where the magnetic susceptibility closest to the average value is newly set as the center and the magnetic susceptibility range that can be recognized as a genuine bill is determined, even if genuine bills having a specific magnetic susceptibility are biased, Without discriminating the range of magnetic susceptibility that can be mistakenly recognized as a genuine note, the identification sensitivity is automatically adjusted to prevent the reduction of the true note recognition rate due to the years of use of the bill validator, and the magnetism that can be recognized as a genuine note. Since the readjustment work of the rate range is unnecessary, the labor and time required for the maintenance of the bill validator are significantly reduced.

Further, as described above, a plurality of susceptibility-value-based genuine bill number counters C ₁ , C ₂ , ..., C _m , ..., C _n−1 , for each susceptibility value that can be recognized as a genuine bill.
By providing C _n and using the divider 7 to divide the number of genuine bills for each magnetic susceptibility value by the total number of genuine bills, in the calculation of the average value and the standard deviation, the magnetic susceptibility value for each inserted bill is calculated. The configuration is remarkably simpler than the method of storing, and even when this device is configured by using a microcomputer, the memory capacity is saved and the arithmetic processing algorithm is simplified. The calculation speed can be improved by.

Further, by using the formula (2) of the standard deviation δ as a formula in which the total number of genuine bills Ns is sufficiently large, the following formula (3) is used to further simplify the calculation processing algorithm and reduce the calculation speed. It can be improved.

As described above, the present invention is a magnetic sensor that detects the magnetic susceptibility of the magnetic material of the printing portion of the inserted bill, and an A / D that converts the magnetic susceptibility detected by the magnetic sensor into a digital signal.
With the converter and the A / D converter, the magnetic susceptibility converted into a digital signal is discriminating means for discriminating whether or not it is within the magnetic susceptibility range that can be recognized as a genuine note, and the total number of genuine bills inserted. A counter for counting, a plurality of counter groups for counting the number of genuine notes having the magnetic susceptibility value for each of a plurality of magnetic susceptibility values within a magnetic susceptibility range that can be recognized as a genuine note, and the plurality of counter groups Of the total number of genuine bills, a divider that calculates the standard deviation and average value of the magnetic susceptibility when the total number of genuine bills reaches a certain value, and the standard deviation When the value within the range is reached, the magnetic susceptibility closest to the average value is newly provided, and the determining means is provided for determining the magnetic susceptibility range that can be recognized as a genuine note,
When the total number of genuine bills reaches a certain value, the standard deviation and average value of magnetic susceptibility are calculated, and only when the standard deviation reaches a value within a specific range, the magnetization closest to the average value is calculated. By deciding the magnetic susceptibility range that can be recognized as a genuine bill with a new rate as the center, even if a genuine bill with a specific magnetic susceptibility is biasedly inserted, the magnetic susceptibility range that can be mistakenly recognized as a genuine bill To automatically adjust the recognition sensitivity without determining the , The time and effort required for maintenance of the bill validator are significantly reduced, and the number of genuine bills for each magnetic susceptibility value is divided by the total number of genuine bills to calculate the average value and the standard deviation. Compared to the method of storing the magnetic susceptibility value for each Configuration is simplified, in which the apparatus can be stably realized.

[Brief description of drawings]

FIG. 1 is a block diagram of an automatic discrimination sensitivity adjusting device for a bill validator showing an embodiment of the present invention, FIG. 2 is a distribution diagram of magnetic susceptibility of printing ink of bills, and FIG. 3 is an embodiment of the present invention. 3 is a flowchart showing the operation of FIG. 1 ... Magnetic sensor, 2 ... A / D converter, 3 ... Discrimination means, 4 ... Banknote storage mechanism, 5 ... Banknote return mechanism, 6 ...
Total genuine note number _{counter, C 1, C 2, C} m, C n-1, C n ...... susceptibility value-genuine bill number counter, 7 ...... divider, 8 ...... average value calculator, 9 ......
Standard deviation calculator, 10 ... Determination means.

Claims (1)

[Claims] 1. A magnetic sensor for detecting a magnetic susceptibility of a magnetic material of a printing portion of a deposited bill, an A / D converter for converting the magnetic susceptibility detected by the magnetic sensor into a digital signal, and the A / D.
A discriminating means for discriminating whether or not the magnetic susceptibility converted into a digital signal by the converter is within a magnetic susceptibility range that can be recognized as a genuine note, a counter for counting the total number of genuine bills inserted, and a genuine bill For each of a plurality of magnetic susceptibility values in the magnetic susceptibility range that can be recognized as, a plurality of counter groups that count the number of genuine bills having the magnetic susceptibility value, and the count value of the plurality of counter groups are the total number of genuine bills. When the total number of genuine bills reaches a certain value, the divider that calculates the standard deviation and average value of the magnetic susceptibility, and when the standard deviation reaches a value within a specific range In addition, a discrimination sensitivity automatic adjusting device for a bill discriminating machine having a deciding unit for deciding a magnetic susceptibility range that can be recognized as a genuine bill with a magnetic susceptibility closest to the average value as a center.