JPH0555917B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to various types of printed paper sheets such as banknotes,
The present invention relates to a device for determining authenticity and fitness.

[Conventional technology]

Banknotes currently in circulation in Japan include the 1,000 yen bill,
There are three types: 5,000 yen bills and 10,000 yen bills. In order to automatically handle these items using terminal equipment installed at banks, etc., the terminal equipment must identify the denomination of the deposited banknotes, determine their authenticity, determine whether they are fit or not, and determine whether the banknotes are genuine or not. Banknotes with little damage should be stored for withdrawal by the terminal user, and counterfeit or heavily damaged banknotes should be rejected so as not to be returned to the terminal user.

Conventional banknote determination devices for this purpose include those described in, for example, Japanese Patent Laid-Open Nos. 57-196382 and 56-149684. In this conventional device, a partial image in a predetermined area is cut out from the entire image of a captured banknote, and the degree of similarity between this partial image and a corresponding partial image of a valid banknote is determined to determine the type of banknote and whether it is correct or not.

[Problem to be solved by the invention]

The conventional device described above determines the type of banknote, etc. based on a partial image of the banknote, so if there is damage in a location that is outside the partial image, it cannot be determined that the banknote is a damaged note. There is a problem. For example, if the image of the central part of a banknote is used as the image for determining whether the banknote is correct or not, even if the corner of the banknote has a crease, or a large area other than the partial image for determination is stained with ink, etc. Unable to reject banknotes.

Further, the conventional device described above performs pattern matching of detailed images of a predetermined area of a banknote to determine the degree of similarity with a genuine bill image, which results in a problem that the device configuration becomes complicated and manufacturing costs increase.

An object of the present invention is to provide a discriminating device that can determine the type, authenticity, and fitness of paper sheets with a simple device configuration.

[Means to solve the problem]

The above objects are: (a) a sensor that receives light from a light emitting source through a sheet of paper, the sensor comprising a group of light-receiving elements arranged one-dimensionally longer than the sheet of paper; (b) (c) a memory that stores data indicating the standard dimensions of paper sheets for each type of paper sheets and data indicating the standard dimensions of the printed portion of the paper sheets; (d) means for capturing the detected value of each of the light receiving elements every predetermined conveyance distance when the sensor passes between the sensor and the light emitting source in a direction intersecting the longitudinal direction; (e) a first comparison means that compares the detected value of each of the light receiving elements with a first threshold value to produce a binary signal of "presence" or "absence" of the paper sheet; and (e) a second threshold value different from the first threshold value. (f) a second means that compares the printed pattern with the value and converts it into a binary signal of "presence" or "absence" of the printed pattern on the paper sheet; A determining means that compares the obtained cumulative number data of the paper sheet "present" signal and the cumulative number data of the print pattern "present" signal with data stored in the memory to determine the type of paper sheet to be inspected and whether or not it is defective. This is achieved by configuring a paper sheet determination device with and.

[Effect]

Paper sheets often have different external dimensions depending on their type. Furthermore, the dimensions of the patterns (printed parts) printed on the surface of paper sheets often differ. Therefore, by determining the combination of the two, it is possible to determine the type of paper sheet.

Therefore, in the present invention, each time a paper sheet is conveyed a predetermined distance, the detection signal of each light-receiving element of the sensor (even if the one-dimensional sensor is scanned every time the paper sheet is conveyed a predetermined distance and each detection signal is obtained, It is also possible to make all the light emitting sources emit light and obtain detection signals from all the light receiving elements at the same time.)
A binary signal indicating the presence or absence of paper sheets is extracted from the first threshold value, and the external dimensions of the paper sheet in the lateral direction (direction perpendicular to the transport direction) are obtained. The width of the paper sheet in the vertical direction (conveyance direction) is determined from the accumulated data of the signal, and these are compared with the standard dimensions stored in the memory.

Furthermore, the horizontal dimension of the printed part is obtained by extracting a binary signal indicating the presence or absence of the printed part from the detection signal of the one-dimensional sensor using the second threshold, and the printed part is determined from the accumulated data of the printed part presence/absence signal for each predetermined conveyance distance. Find the vertical width of and compare these with standard dimensions stored in memory.

These results make it possible to determine the type of paper sheet.

Regarding paper sheets to be inspected, count values in the one-dimensional sensor direction (horizontal direction) of paper sheet presence/absence signals and printing presence/absence signals obtained from the detection values of each light receiving element of the one-dimensional sensor, and for each predetermined transport distance (vertical direction) are calculated. The cumulative number of vertical directions (directions) is the vertical direction at the corresponding position of the sheet,
Matches standard horizontal dimensions within tolerance.
However, if the paper sheet has folds, holes, stains, etc., there will be parts where the above-mentioned counted value or cumulative value deviates from the standard size. Therefore, it can be determined that the paper sheet has folds, holes, or stains.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows the arrangement of sensors for detecting the condition of printed matter such as paper sheets, especially banknotes, and a signal processing circuit, and this figure will be described below. In the figure, numeral 1 indicates a banknote that is conveyed in the horizontal direction, and passes through the sensor section one after another while being held by a conveyor belt (not shown). This sensor unit (constituent feature (a) in the claims) includes a light emitting source 2, such as an LED, which irradiates the banknote 1 with light from the back surface, and a group of light receiving elements 3a, 3b, 3c, and 3d arranged in an array. ，
3e, the light emitting source 2 and the light receiving element group 3
The amount of transmitted light of the banknote 1 passing through the gaps between a to 3e is photoelectrically converted. The light-receiving element groups 3a to 3e each have 8 light-receiving elements such as photodiodes arranged in a series of arrays, and have a total of 5 bends, including 3 bends and both ends that occur when the banknote 1 is folded into quarters. Scan each area separately. This area is particularly effective in detecting the degree of damage to banknotes during the distribution process, as well as tears, folds, etc. The outputs of the light-receiving element groups 3a to 3e are output every clock at a constant distance from the encoder 4 synchronized with the conveyance speed.
The address control unit 5 sequentially scans from the light receiving element group 3a to the light receiving element group 3e. The outputs of each of the eight light receiving elements constituting each of the light receiving element groups 3a to 3e are sent to multiplexers 6a, 6b, 6c, 6d, 6
The preamplifiers 7a, 7b, 7c,
7d and 7e, respectively.

Each output of the preamplifiers 7a to 7e is further sequentially switched by a multiplexer 8 and then input to an automatic gain compensation circuit 9. Automatic gain compensation circuit 9
consists of a RAM 10 and a main amplifier 11 whose amplification factor can be freely set using the output of the RAM 10. This function increases or decreases the amplification factor for each of the 40 light-receiving elements in total without passing the banknote 1, and when the light-receiving output reaches the specified value, this amplification factor is sequentially written to the RAM 10. put. When the bill 1 passes, the values corresponding to each light receiving element are read out from the RAM 10 and the main up 1 is loaded.
An amplification factor of 1 is set. This compensates for variations in sensitivity, temperature and aging of individual amplifiers,
A constantly stable output signal is obtained and binarization can be performed using a common threshold value. Note that the component (c) described in the claims is comprised of multiplexers 6a to 6e, preamplifiers 7a to 7e, and multiplexer 8 in this embodiment.

The gain-compensated output of the light receiving element is sent to the comparators 12 (first comparison means: feature (d) in the claims) and 12' (second comparison means: feature (e) in the claims). is input. Comparator 12
As shown in the characteristic diagram of FIG. 2, the light reception output is binarized at a threshold value V ₁ (first threshold value) for detecting the presence or absence of a banknote 1, and a signal indicating the presence of a banknote is output.

On the other hand, the comparator 12' has a threshold value for detecting the presence or absence of a printed pattern, as shown in the characteristic diagram of FIG.
The configuration is such that the output of the light receiving element is binarized at V ₂ (second threshold value) and a signal with a printed pattern is output.

The banknote presence signal is from counters 13m, 13ae,
13bd, 13c, RAMs 14a, 14e, counter group 15, and holding circuit 16, respectively. Among these, the counter 13m is located in the entire banknote area of the light receiving element groups 3a to 3e.
ea is connected to the light receiving element groups 3a and 3e, counter 13bd is connected to the light receiving element groups 3b and 3d, and the counter 13
c corresponds to each area of the light receiving element group 3c, and
The number of pixels with banknotes is counted sequentially for each scan from the start to the end of the passage. RAM14a corresponds to the light receiving element group 3a, RAM14e corresponds to the light receiving element group 3e,
The number of pixels with banknotes for each scan is sequentially stored. The counter group 15 is composed of 24 counters (8 elements x 3 groups) corresponding to each of the light receiving elements of the light receiving element groups 3b, 3c, and 3d, and sequentially counts the pixels with banknotes of each light receiving element for each scan.

Furthermore, when the holding circuit 16 is scanned in synchronization with the clock of the encoder 4 at fixed distance intervals, during the period from the time when any one of the 40 elements detects that there is a banknote present, to the time when all the elements detect that there is no banknote. ,
It outputs a signal while passing.

On the other hand, the signal indicating the presence of a print pattern is sent to counter 1.
7m, 17ae, 17bd, and 17c, the counter 17m is the entire area of the banknotes in the light receiving element groups 3a to 3e, the counter 17ae is the light receiving element groups 3a and 3e, the counter 17bd is the light receiving element groups 3b and 3d, Counter 17c is counter 3
The number of pixels with a print pattern for each scan is sequentially counted for each area of c.

When data reading for one bill is completed from the start to the end of passage of bill 1, the counters 13m, 13
ae, 13bd, 13c and 17m, 17ae, 1
The counting results of 7bd and 17c are input to the comparison and determination section 18. Then, in this comparison and determination section 18,
In addition to the number of pixels with each denomination of banknotes and the number of pixels with a printed pattern corresponding to each counting result stored in the memory 19 (constituent feature (b) of the claims),
The lower limit value is also input, and the comparison/judgment unit 18 (constituent feature (f) of the claims) sequentially compares and collates the two, and if all the results indicate the same denomination, the denomination is If there is a banknote in the special area and the number of pixels is small, or if there is a printed pattern and the number of pixels is large or small, it will be determined that there is significant damage, dirt, or oil adhesion, and the paper will be rejected. Outputs the next judgment result. Note that 20 is an arithmetic determination unit for determining the number of pixels with banknotes in the sensor group, and 21 is a comprehensive determination unit, which are configured as part of a microcomputer 22 as a determination means. Further, 19' is a memory inserted before the arithmetic and determining section 20, and once the number of pixels with a bill is stored in this memory 19', the arithmetic and determining section 20
This is for inputting information to the user.

A second judgment is further carried out based on the storage results of the RAMs 14a and 14e and the counting results of the counter group 15, which are used to detect holes, tears,
This detects the presence or absence of defects in the banknote 1, such as folded edges. This will be explained with reference to the plan view of FIG.

FIG. 3 shows the relationship between the banknote 1 and the banknote presence pixels (hatched portions) obtained from the output of each light-receiving element, and the RAMs 14a and 14e include light-receiving element groups 3a and 3e, which are the opposite ends of the banknote 1. The bill present pixel state for each scan is stored. First, banknote 1
In order to find the four corner positions of
0, the contents of the RAMs 14a and 14e are sequentially read out. Then, in the light receiving element group 3e in FIG.
Assuming search lines A, B, C, and D with angles of 45°,
The point where this intersects the pixel with paper for the first time is found.

Specifically, taking the four corner positions ( _{Xe 1} , Ye ₁ ) in the upper right corner of the paper in FIG. } The position that satisfies the condition, that is, (Ln=5,
n=5) are the four corner positions (Xe ₁ ,
Ye ₁ ). Thereafter, the remaining three four corner positions are determined in the same manner.

The four corner positions obtained in this way are (Xa ₁ , Ya ₁ ) = (3, 1) (Xa ₂ , Ya ₂ ) = (5, 11) (Xe ₁ , Ye ₁ ) = (5 , 5) (Xe ₂ , Ye ₂ ) = (2, 17).

Next, the inclination SKW of the transported bill 1 is determined by the following formula, and it is detected that the inclination SKW does not exceed the allowable value read from the memory 19'.

SKW=|Ya ₁ , Ye ₁ |=|1-5|=4 In addition, the outer dimensions of the banknote 1 are determined from the following formula.

_X1 =Xa _{1 + Xe 1 = 3} +5 _{= 8} Since Y1 is shorter than the standard size read out from the memory 19', folded edges can be detected at the four corner positions (Xa ₂ , Ya ₂ ) at the lower left of the paper in FIG.

Furthermore, the presence or absence of tearing at the end can be determined from the following formula, which sequentially adds the dimensions of both ends between the Y1 and Y2 dimensions.

Xa ₃ +Xe ₃ =4+5=9 Xa ₄ +Xe ₄ =4+5=9 Xa ₅ +Xe ₅ =4+4=8 Xa ₆ +Xe ₆ =4+4= _{8 Xa 7 +} Xe ₇ = ₄ +4=8 From this , Xa ₈ +Xe ₈ is shorter than the standard size read from the memory 19', and a break in Xe ₈ can be detected.

On the other hand, the counter group 15 counts the number of paper pixels of the banknote 1 corresponding to each of the 24 light-receiving elements, that is, the width dimension of each light-receiving element. These counting results are sequentially input to the calculation/judgment section 20,
It is compared with the standard dimensions stored in the memory 19' in the following manner.

3b ₁ =13 3b ₂ =13 3b ₃ =11 3b ₄ =13 3b ₅ =13 3b ₆ =13 3d ₄ =13 3d ₅ =11 3d ₆ =13 3d ₇ =13 3d ₈ =13 This makes 3b ₃ and 3d _6It is detected that the item is shorter than the standard size, has tears, or has holes.

Therefore, in the second determination, it is possible to accurately detect defects such as folded edges, tears, holes, etc. that are difficult to detect using only the first count of pixels with paper.

The thus obtained defect determination results, such as bent edges, tears, and holes, are input to the comprehensive determination section 21 shown in FIG. 1 together with the first denomination determination results.
This comprehensive judgment section 21 performs a logical product of the first denomination result (output of the comparison judgment section 18) and the second defect presence/absence result (output of the calculation judgment section 20), The determination result as to whether the banknote should be stored or rejected is output from the terminal 23.

In the above embodiment, the description focused on determining the denomination of the banknote 1, but if you also want to determine whether the banknote is good or bad, the upper and lower limit values of each standard data may be set to the boundary value between a good note and an unfit note. All you have to do is set . In other words, for the number A of pixels with paper in the first determination, A1 (upper limit)>
Set the standard data of A2 (boundary value) > A3 (lower limit value), (1) If A1≧A>A2, it is a good note (2) If A2≧A>A3, it is an unfit note (shrinkage after washing, missing) (3) Reject if A>A1 or A3>A.

In addition, for the number of pixels with printing pattern P, set P1 (upper limit) > P2 (upper boundary value) > P3 (lower boundary value) > P4 (lower limit), and (1) If P2≧P>P3, Good note (2) If P1≧P>P2 or P3≧P>P4, the note is damaged (stained, discolored, or oily) (3) If P>P1 or P4>P, reject.

Also, in the second defect determination, as with the first paper present pixel number, if (upper limit value)>(boundary value)>(lower limit value) is set, it is possible to determine whether the image is normal or defective.

In the above-described embodiment, the scanning area of the banknote 1 is divided into five parts, and the detection means is constituted by a group of light-receiving elements each consisting of eight light-receiving elements. More detection element groups can also be used for this purpose. Furthermore, even with a minimum of two divisions and one light-receiving element for each, defects in banknotes, etc. can be sufficiently detected.

In addition, if it is necessary to correct the positional deviation of the printed matter in the number of pixels with a printed pattern in the first judgment, it is necessary to correct the positional deviation based on the size comparison of the end dimensions in areas 3a and 3e on the left and right sides of the paper in Figure 3. What is necessary is to detect the amount of positional deviation and prepare standard data corresponding to this amount of positional deviation.

Furthermore, in FIG. 3, a case has been described in which the banknote 1 is conveyed in an inclined manner, but a conveyance direction correcting means is provided so that the banknote 1 can be conveyed at right angles to the scanning direction of the sensor. In some cases, the circuit configuration may be a little simpler. That is,
The transport inclination SKW of banknote 1 is a negligible value (SKW≦
In the case of 1), there is no need to temporarily store the banknote present pixel state in the RAM, and the number of banknote present pixels of both left and right sensor groups can be immediately input to the calculation/judgment section 20, so the memory 19' shown in FIG. 1 is unnecessary. becomes.

The embodiments described above relate to paper sheets in which the printed portion is smaller than the entire surface of the paper. Some paper sheets are printed on the entire surface of the paper. The standard dimensions of such paper sheets are characterized in that the external dimension and the dimension of the printed part are the same, and this characteristic data stored as the standard dimension in the memory 19,
It can be determined from the detection signal of the one-dimensional sensor and the signals extracted at the first and second threshold values.

Furthermore, some paper sheets have a watermark area in the printed portion. When determining such paper sheets, if the standard dimensions stored in the memory 19 have only the dimensions of the outermost contour of the printed portion, the outermost contour of the printed portion is determined based on the sheet presence detection signal. Find the dimensions of. In addition, if the standard dimensions are given as the sum of the dimensions of the left and right printed parts excluding the watermark area (the watermark area is white, it will not be printed in the judgment of the second threshold value), then the one-dimensional sensor The determination is made by calculating the total number of printing presence detection signals and comparing this with the standard dimensions.

According to the above embodiment, since damaged paper sheets can be accurately rejected, the occurrence of jams during the conveyance process is greatly reduced, and there is no need to visually re-check the paper sheets. It has the advantages of high reliability, high speed, and labor saving.

〔Effect of the invention〕

According to the present invention, the type of paper sheet can be accurately determined without being affected by the conveyance direction, and folded edges, defects, etc. can also be detected with high precision at high speed, and a highly reliable paper sheet discrimination device is provided. can be obtained.

[Brief explanation of the drawing]

Fig. 1 is for explaining one embodiment of the present invention, and shows the sensor arrangement and signal processing circuit diagram, Fig. 2 is a received light output waveform diagram of the printed matter detection sensor, and Fig. 3 shows the conveyance state of the printed matter, and the printed matter. FIG. 3 is a diagram illustrating the relationship between the damaged state and the paper-present pixel of the printed matter. 1...paper leaves, 2, 3a, 3b, 3c, 3d,
3e...Sensor, 13m, 13ae, 13bd, 1
3c, 15, 17m, 17ae, 17bd, 17c
... Counting means, 18 ... Comparison means, 19, 19'
...Memory, 20, 21...Discrimination means.

Claims (1)

[Scope of Claims] 1 (a) A sensor that receives light from a light emitting source through a sheet of paper and is composed of a group of light-receiving elements arranged one-dimensionally longer than the sheet of paper; (b) a memory that stores data indicating the standard dimensions of paper sheets for each type of paper sheets and data indicating the standard dimensions of the printed portion of the paper sheets; means for capturing detection values of each of the light receiving elements every predetermined transport distance when the sensor is transported in a direction intersecting the longitudinal direction of the sensor and passes between the sensor and the light emitting source; (d) detection of each of the light receiving elements; (e) a first comparing means that compares the value with a first threshold value and converts the value into a binary signal of "presence" or "absence" of the paper sheet; (f) a second comparison means that compares it with a second threshold value and converts it into a binary signal of "presence" or "absence" of the printed pattern on the paper sheet; Compare the cumulative number data of the paper sheet "presence" signal and the cumulative number data of the print pattern "presence" signal obtained for each transport distance with the data stored in the memory to determine the type of paper sheet to be inspected and whether or not it is defective. A paper sheet discriminating device comprising: a determining means for determining;