JPH04162190A - Automatic adjusting device for identification sensitivity for bank note identifier - Google Patents

Abstract

PURPOSE:To prevent the deterioration of the recognition rate of a real note by newly deciding the judgement range of the new note with a transmission factor nearest to an average value as a center when the total sum of the notes reaches a prescribed value and when the standard deviation of the transmission factor reaches a specified range in the identification of the real notes by means of the transmission factor of light. CONSTITUTION:A discrimination means 3 receives a transmission factor digital signal 2a for the inputted notes and discriminates whether it is within a transmission factor range where the notes can be recognized to be real. When the notes are recognized to be real, a real note signal 3a, a real note count pulse 3b and a real note count pulse by individual transmission factor S are outputted. When the total number of the real notes reaches a prescribed one, a total real note number counter 6 outputs a signal 6a. When the signal 6a is received, a divider 7, an average value computing element 8 and a standard deviation computing element 9 calculate the average value and the standard deviation of the transmission factor. A decision means 10 decides the transmission factor range of the recognition of the real notes with a transmission factor value nearest to the average value as the new center when the within standard deviation reaches within the specified range.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a banknote recognition machine used in, for example, a vending machine or a money changer, and particularly to an automatic recognition sensitivity adjustment device thereof.

BACKGROUND OF THE INVENTION Generally, in a banknote validating machine, the dimensions of the banknote to be identified,
The authenticity of the inserted banknotes is determined by detecting the thickness and density of printing ink. As an example,
As described in Japanese Patent No. 716, a method is disclosed in which the density of printing ink is detected by an optical sensor, compared with a reference value, and authenticity is determined based on whether the density is within an allowable error range.

Problems to be Solved by the Invention However, the density of printing ink varies slightly depending on when the banknote was manufactured, and changes quickly with use. There are differences.

Therefore, in conventional banknote validating machines, the genuine banknote recognition rate significantly decreases as the number of years of use increases.

In addition, there were some machines that made it possible to adjust the transmittance range that could be recognized as genuine notes, that is, the recognition sensitivity, and readjust the transmittance range once every few years, but by this time, banknote validators had already been widely dispersed in the market. Because of this, readjustment work was extremely time-consuming and labor-intensive.

The present invention solves the above problems, and by automatically adjusting the recognition sensitivity of a bill validator, it prevents a decline in the recognition rate of genuine bills due to the number of years of use of the bill validator, and also prevents the recognition rate of genuine bills from decreasing. An object of the present invention is to provide an automatic recognition sensitivity adjustment device for a banknote validator that eliminates the need for readjustment of the rate range.

Means for Solving the Problems In order to solve the above problems, the automatic recognition sensitivity adjustment device for a banknote validating machine of the present invention includes an optical sensor that detects the light transmittance of the printed part of the input banknote, and a An A/D converter converts the detected transmittance into a digital signal, and the A/D converter determines whether the transmittance converted into a digital signal is within a transmittance range that can be recognized as a genuine note. a counter for counting the total number of genuine bills of the input banknotes; and a counter for counting the total number of genuine bills having the transmittance value for each of a plurality of transmittance values within a transmittance range that can be recognized as genuine bills. a plurality of counter groups, a divider that divides the counted value of the plurality of counter groups by the total number of genuine notes, and a standard deviation of the transmittance when the total number of genuine notes reaches a certain value. When the computing unit that calculates the average value and the standard deviation reach a value within a specific range, a decision is made to determine a new transmittance range that can be recognized as a genuine note, with the transmittance closest to the average value as the center. It is equipped with means.

According to the above-described configuration, the present invention calculates the standard deviation and average value of the transmittance when the total number of genuine notes reaches a certain value,
Only when the standard deviation reaches a value within a specific range, a new transmittance range that can be recognized as a genuine note is determined using the transmittance closest to the average value as the center. Detects differences in shading depending on manufacturing date, automatically adjusts identification sensitivity, prevents decline in genuine note recognition rate due to age of bill validator, and readjusts magnetic susceptibility range for recognizing genuine notes. This eliminates the need for

EXAMPLE Hereinafter, an automatic recognition sensitivity adjustment device for a banknote validator according to an example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of an automatic recognition sensitivity adjustment device for a banknote validator according to an embodiment of the present invention.

In Figure 1, reference numeral 1 denotes an optical sensor that detects the light transmittance of the printing part of the inserted banknote and sends an analog signal corresponding to the transmittance. Output 1a
issue. 2 is an A/D converter which converts the analog signal output 1a of the optical sensor 1 into a digital signal output 2a and outputs the digital signal output 2a. 3 is a determining means which receives the digital signal output 2a of the A/D converter 2 and determines whether or not the transmittance is within a transmittance range that can be recognized as a genuine note. If the value is within the range that can be recognized as a genuine note, the genuine note signal 3& and genuine note count pulse 3b are output, and the transmittance value is within the range that can be recognized as a genuine note, with the transmittance value X as the center value. n (n is any integer) transmittance (i.e. "1 +"2+"""*
It is determined which transmission value of "ms""t"n-1,"n) it has, and the true bill count A)renu St corresponding to each transmission value is output.

Here, Si is Sl, S2. .......

S... Indicates the m++n-In output of either one of S and S.

In addition, if the note is not within the range that can be recognized as a genuine note, the counterfeit note signal 3
Output C. Reference numeral 4 denotes a banknote storage mechanism which receives the genuine banknote signal 3a from the discriminating means 3 and stores the inserted banknotes. In addition, based on the genuine note signal 3a, a vending machine performs a selling operation, a currency exchange machine performs a money exchange operation, etc. 6 is the banknote return mechanism,
Upon receiving the counterfeit bill signal 3C from the discriminating means 3, the inserted bill is returned.

Reference numeral 6 denotes a total number of genuine bills counter, which receives the genuine bill count pulse 3b from the discriminating means 3, counts the total number of genuine bills Nm, and outputs the counted value. Further, when the total number of genuine notes N8 reaches a certain fixed value, a count 1 sub signal 6a is output. here,
The certain constant value is a value large enough to examine the density of printing ink on banknotes on the market and the distribution of light transmittance of the printed portion. C1, C2,...'C
ml..., Cn, .

Cn is a group of counters for the number of genuine banknotes by transmittance value, and a genuine banknote count pulse S1 . S2゜・・・・・・
, Srn, 5n-1, Sn, the number of genuine notes by corresponding transmittance value N, , N2 .・・・・・・＋Nmt・
song·.

Count Nn-1 and Nn and output the counted value.

7 is a divider which receives the count-up signal 6a from the total number of genuine notes counter 6 and sequentially divides the number of genuine notes by transmittance value N1 from the above-mentioned transmittance value-based genuine notes counter Ci into the total number of true notes. The calculation is performed by dividing by the total number of genuine bills Ng from the ticket number counter 6, and the division result Qi
(=Ni/Ns) is output to the average value calculator 8 and standard deviation calculator 9. Here i is 1, 2.・・・・・・、
Indicates the value of m, n-1, or n. The average value calculator 8 receives the division result Qi from the divider 7, calculates the average value i according to equation (1) shown below, and sends the calculation result to the standard deviation calculator 9 and the determining means 10. Output to.

(1) The standard deviation calculator 9 receives the division result Qi from the divider 7 and the average value i from the average value calculator 8. Then, f2 shown below
>The standard deviation δ is calculated using the formula, and the calculation result is output to the determining means 10.

The determining means 10 receives the average value i from the average value calculator 8 and the standard deviation δ from the standard deviation calculator 9, and calculates the standard deviation δ of the printing part of banknotes distributed in the market. Only when a value within a certain range corresponding to a legitimate distribution of light transmittance is reached, the new transmittance value closest to the positive average value can be recognized as a genuine note. It functions to determine the transmittance range, output a determination signal 10a, and control the discrimination means 3.

The operation of the automatic recognition sensitivity adjustment device for the banknote validating machine configured as described above will be described below with reference to FIGS. 2 and 3.

First, the light transmittance of the printing part of a banknote circulating in the market at a certain point in time is the transmittance f, as shown in A in Figure 2.
Centered around f1xrQ! The distribution ranges from 1 to xxl, and the distribution is a normal distribution.

As years pass, the transmittance of banknotes circulating in the market changes as shown in B in FIG. 2 due to differences in the time of manufacture, but the distribution width remains almost constant.

Therefore, in order to detect this difference due to manufacturing time, the present device operates as follows, as shown in FIG. 3.

Here, the total number of genuine banknotes counter 6 counts and stores the total number of genuine banknotes N8 of the banknotes that have been input so far, and the number of genuine banknotes counter group c1. C2, hit”tq.

......, Cn,, Cn is the number of genuine notes by transmittance value NN ......, N ......, N knee,, Nn is the counting record 112'm' It is assumed that you remember it.

When a banknote is inserted into the banknote validator (5lop 1), the optical sensor 1 outputs an analog signal 1a corresponding to the transmittance, and the A/D converter 2 converts it into a digital signal 2& (5tep 2) ). If the inserted banknote is a counterfeit note (
5top 3), a counterfeit bill signal 3C is output from the discrimination means 3, and the inserted bill is returned by the bill return mechanism 6 (5top 4).

If the inserted bill is a genuine bill (5tep5), a genuine bill signal 3a is output from the discrimination means 3, and the inserted bill is stored in the bill storage mechanism 4 (5top 6). Then, the genuine bill count-up 3b is output, and the total number of genuine bills counter 6 counts the total number of genuine bills N1 (gtep 7).

Further, if the permeability value of the inserted banknote is Xa, the corresponding true note count pulse Sa by permeability value is output, and the corresponding genuine note count counter Ca by permeability value is counted by the permeability value. Count Na (gtep 8).

Next, when the total number of genuine notes NB reaches a certain value (5to
p9), the total number of genuine banknotes counter 6 outputs a count-up signal 6a (sl@p10). Here, the certain constant value is a value large enough to examine the distribution of light transmittance of the printed portion of the banknote. Next, the divider 8 receives the count-up signal 6a and sequentially performs division (5to
p 11 ), division result Q i (= Ni /Ns
) is output. Then, the average value calculator 8 performs the above (1).
According to the formula, calculate the average *x (gtep12),
Output the average value i. Then, the standard deviation calculator 9 calculates the standard deviation δ according to the above equation (-) (stop1
3) Output the standard deviation δ. Next, the determining means 10 receives the average value i and the standard deviation δ, and determines whether the standard deviation δ corresponds to a distribution that is considered to be valid for the light transmittance of the printed portion of banknotes distributed in the market. If a value within the range of (s
step14), average II! Determine the transmittance range that can be recognized as a genuine note, centering on the transmittance value closest to
The decision signal 10a is output to control the discrimination means 3 (st
ep15).

Then, the determining means 10 outputs a clear signal 10b,
The total number of genuine banknotes counter 6 and the group of genuine banknotes counters by transmittance value C1, C2, . . . , C, . . . p
c! 1-j Clear all PC Yu 5top 1
6) The total number of genuine notes counter 6 and the number of genuine notes per transmittance value counters C1, C2, . . . , CC start counting anew.

n-1'n According to the automatic discrimination sensitivity adjustment device of the banknote validating machine shown in the above embodiment, there is an optical sensor 1 that detects the light transmittance of the printing part of the inserted banknote, and a light transmittance detected by the optical sensor 1. an A/D converter 2 that converts transmittance into a digital signal, and the A/D
a determining means 3 for determining whether the transmittance converted into a digital signal by the converter 2 is within a transmittance range that can be recognized as a genuine note; and a total number of genuine bills for counting the total number of genuine bills of input banknotes. a counter 6, and a group CIPC2' of a plurality of genuine bill number counters by transmittance value that counts the number of genuine bills having a transmittance value for each of a plurality of transmittance values within a transmittance range that can be recognized as genuine bills.・・・・・・＊C
m+..., Cn-11cn, and the plurality of counter groups CI 1 C2? “”” l Crn1””・
, Cn-1, a divider 7 that divides the count value of Cn by the total number of genuine notes, and an average value calculator 8 that calculates the average value of transmittance when the total number of genuine notes reaches a certain value. and a standard deviation calculator 9 that calculates the standard deviation of the transmittance, and when the standard deviation reaches a value within a specific range, the transmittance value closest to the average value is newly set as the center and a genuine note is calculated. With the above configuration, when the total number of genuine notes reaches a certain certain value, the standard deviation and average value of the transmittance are calculated. , Only when the standard deviation reaches a value within a specific range, a new transmittance range that can be recognized as a genuine banknote is determined using the transmittance closest to the average value as the center. It detects the difference in the shade of printing ink depending on the manufacturing date and automatically adjusts the recognition sensitivity to prevent the decline in genuine note recognition rate due to the age of the banknote validator, and also to reduce the transmittance range that can be recognized as a genuine note. Since there is no need for readjustment work, the effort and time required for maintenance of banknote validators can be significantly reduced.

In addition, as mentioned above, the standard deviation and average value are used to determine the transmittance range that can be recognized as new genuine notes. Therefore, the transmittance range that can be recognized as a genuine note cannot be determined.

In addition, as described above, a plurality of genuine bill number counters C1, C2 for each transmittance value that can be recognized as a genuine bill...
, am, . . ., Cn, , 1. By providing Cn and using the divider 7 to divide the number of genuine bills for each transmittance value by the total number of genuine bills, the transmittance value can be calculated for each inserted banknote in calculating the average value and standard deviation. This method significantly simplifies the configuration compared to the method of storing data in memory.Also, when configuring this device using a microcomputer, it is possible to save memory capacity and improve the calculation processing algorithm. It is a chaotic method that can improve calculation speed through simplification.

In addition, the standard deviation δ calculation formula (formula 9 is shown below assuming that the total number of genuine notes Ns is sufficiently large) (by using the formula, the calculation processing algorithm can be further simplified and the calculation speed can be improved. It is something that can be achieved.

Effects of the Invention As described above, the present invention includes an optical sensor that detects the light transmittance of the printed part of the inserted banknote, and an A/D converter that converts the transmittance detected by the optical sensor into a digital signal. , a determining means for determining whether the transmittance converted into a digital signal by the A/D converter is within a transmittance range that can be recognized as a genuine note, and a counter for counting the total number of genuine bills of the inserted banknotes. a plurality of counter groups that count the number of genuine notes having a transmittance value for each of a plurality of transmittance values within a transmittance range that can be recognized as genuine notes; and a counter group of the plurality of counter groups. a divider that divides the numerical value by the total number of genuine notes; a calculator that calculates the standard deviation and average value of transmittance when the total number of genuine notes reaches a certain value;
A determination means for determining a new transmittance range that can be recognized as a genuine note, with the transmittance closest to the average value as the center, when the standard deviation reaches a value within a specific range, When the total number of genuine notes reaches a certain value, the standard deviation and average value of the transmittance are calculated, and only when the standard deviation reaches a value within a specific range, the transmittance closest to the average value is calculated. By determining a new transmittance range that can be recognized as a genuine note based on the ratio, the transmittance range that can be mistakenly recognized as a genuine note even if genuine notes with a specific transmittance are thrown unevenly is determined. It detects the difference in the shade of printing ink on banknotes depending on the manufacturing date and automatically adjusts the recognition sensitivity, thereby preventing the deterioration of the recognition rate of genuine banknotes due to the number of years of use of the banknote validator, and distinguishing between genuine and genuine banknotes. In order to eliminate the need to readjust the transmittance range that can be certified,
In addition to significantly reducing the effort and time required for maintenance of bill validators, by dividing the number of genuine bills for each transmittance value by the total number of genuine bills, it is possible to calculate the average value and standard deviation.
Compared to a method in which the transmittance is stored for each inserted banknote, the configuration is significantly simpler and the present device can be realized at a lower cost.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an automatic recognition sensitivity adjustment device for a banknote validating machine showing an embodiment of the present invention, FIG. 2 is a distribution diagram of the light transmittance of printing ink on banknotes, and FIG. 3 is a flowchart showing the operation of the embodiment. DESCRIPTION OF SYMBOLS 1... Optical sensor, 2... A/D converter, 3... Discrimination means, 4... Bill storage mechanism, 6... ...Banknote return mechanism, 6...Total genuine banknote counter, C1, C2, C work. 0n-1, On...... Genuine bill number counter by transmittance value,
7... Divider, 8... Average value calculator, 9
...Standard deviation calculator, 1o...Decision means. Name of agent Patent attorney Akira J. Kaji et al. 26th
1 Figure 112 Diagram tree

Claims (1)

[Claims] An optical sensor detects the light transmittance of the printing part of the inserted banknote, an A/D converter converts the transmittance detected by the optical sensor into a digital signal, and the A/D converter converts the transmitted banknote into a digital signal. A determining means for determining whether the transmittance is within a transmittance range that can be recognized as a genuine note, a counter that counts the total number of genuine bills of the inserted banknote, and a transmittance that is within a transmittance range that can be recognized as a genuine note. a plurality of counter groups that count the number of genuine notes having the transmittance value for each of the plurality of transmittance values; a divider that divides the counted value of the plurality of counter groups by the total number of genuine notes; A calculator that calculates the standard deviation and average value of transmittance when the number of genuine notes reaches a certain value, and a transmittance that is closest to the average value when the standard deviation reaches a certain value range. An automatic recognition sensitivity adjustment device for a banknote validating machine, which has a determining means for determining a transmittance range that can be recognized as a genuine banknote.