JP5645271B2 - Paper sheet identification device - Google Patents

Description

  The present invention relates to a paper sheet identification device that determines the authenticity of paper sheets represented by banknotes, securities, and cash vouchers.

  In general, cash transaction devices such as ATMs (Automatic Tellers Machines) that handle printed matter such as banknotes and securities and counters installed at the windows of financial institutions determine the authenticity of banknotes and securities. An identification device having an identification function is provided.

  For example, in banknote identification in ATM, a banknote conveyed in a predetermined direction is scanned by a single sensor or a plurality of sensors provided in the identification apparatus, and the identification apparatus reads feature data indicating a print pattern of the banknote. Then, the identification device performs a predetermined calculation on the feature data in the desired area of the bill to calculate a plurality of statistics. It is checked whether or not this statistic (calculated value) is within an allowable range of values (for example, an upper limit value and a lower limit value) set as preset determination values (parameters). Then, if the identification device determines that it is within the set allowable range as a result of the check, the identification device determines that it is a genuine banknote, and if it determines that it is not within the allowable range, it is a fake It is determined that it is a bill. The upper limit value and the lower limit value are threshold values for determination values for determining the authenticity of banknotes.

  However, a sensor mounted on an identification device such as a bill causes sensor output fluctuations due to variations in sensitivity, variations in output level due to disturbance effects such as temperature and humidity, and aging degradation. Therefore, in consideration of these variations and fluctuations, the sensor performs sensor correction before or during operation and configures a correction mechanism that always obtains a constant output, and compares it with a fixed threshold prepared in advance. And true / false judgment is performed.

  As described above, for example, in Patent Document 1, paper sheets are fed out from a storage and identified after correcting the output of the sensor, and accumulated data based on the identification result is used. There has been proposed a paper sheet handling apparatus capable of creating a frequency distribution, an average value, and a standard deviation value, and changing the denomination or authenticity judgment value while checking these information.

JP 2008-15813 A

  The correction of each sensor in the identification device is an optimal correction at a certain time. Normally, there is no problem with such a correction method. However, if there is foreign matter such as dust or dust at the time of the correction, the correction including the influence is performed, but if the foreign matter existing at the time of correction disappears after that, the output of the sensor becomes an unexpected value. For this reason, there is a case where it deviates from the threshold value at the time of determination and causes erroneous determination. In other words, when foreign matter such as dust or dust is present, the sensor output is corrected according to the situation, but the sensor output remains unchanged when the foreign matter disappears thereafter. For this reason, there is a problem that the output of the sensor is not constant and an erroneous determination may occur.

  The present invention has been made in view of the above, and when a foreign object is recognized, it is possible to determine the authenticity of the paper sheet with a certain accuracy regardless of the presence or absence of the foreign object. An object is to provide an identification device.

  In order to solve the above-described problems and achieve the object, a paper sheet identification apparatus according to the present invention is a paper sheet identification apparatus that determines the authenticity of a paper sheet. A sensor for detecting, a storage unit for storing a determination threshold value for determining the authenticity of the paper sheet, a correction unit for correcting the output of the sensor so that an output value is constant, and an output of the sensor When the current correction amount changes abruptly compared to the past correction amount, an identification control unit that changes the determination threshold according to the changed correction amount, and the determination threshold after the change by the identification control unit And a true / false determination unit that determines the authenticity of the paper sheet.

  According to the present invention, when a foreign object is recognized, it is possible to provide a paper sheet identification device that can determine the authenticity of a paper sheet with a certain accuracy regardless of the presence or absence of the foreign object.

It is a figure which shows the structure of the paper sheet identification device in 1st Embodiment. It is a figure which shows an example of a structure of a line sensor. It is a figure which shows the image of the sensor output signal output from the line sensor at the time of production of a paper sheet identification device. It is a figure which shows the image of the sensor output signal output from the line sensor after operation of a paper sheet identification device. It is a figure which shows the example in case a foreign material exists in the line sensor shown in FIG. It is a figure which shows a mode that the output of a line sensor is correct | amended when a foreign material exists in a line sensor. It is a figure which shows the correction amount with respect to the line sensor in which the foreign material existed. It is a figure which shows the relationship between the output value of a line sensor after correction | amendment, and a width | variety (authenticity determination threshold value). It is a figure which shows a mode that the overcorrection is made | formed with respect to the line sensor. It is a figure which shows the example of a structure of a correction amount table. It is a figure which shows a mode that the identification part control program changed the authenticity determination threshold value according to the correction amount. It is a figure which shows a mode that each element of a line sensor was classified into the determination block for the element contained in the predetermined range of the main scanning direction. It is a figure which shows the example of initial determination block data. It is a figure which shows the example in the case of changing the weighting determination value (point) of a determination block according to a fluctuation | variation threshold value ratio. It is a figure which shows the structure of the paper sheet identification device in 2nd Embodiment. It is a figure which shows a mode that a paper sheet identification device performs the comprehensive determination of a banknote using a some sensor.

  Embodiments of a paper sheet identification apparatus according to the present invention will be described below in detail with reference to the accompanying drawings. Below, the case where the paper sheet identification device according to the present invention is configured as a device incorporated in an automatic teller machine such as an ATM (Automatic Tellers Machine) employed in a financial institution such as a banking system is taken as an example. explain.

  FIG. 1 is a diagram illustrating a configuration of a paper sheet identification apparatus 1000 according to the first embodiment. As shown in FIG. 1, the paper sheet recognition apparatus 1000 receives a transport roller 10 for transporting banknotes, a sensor 11 for reading banknote characteristics, and a sensor output signal 12 read according to banknote characteristics. And an identification control unit 13 for performing discrimination processing for authenticity of banknotes.

  The transport roller 10 is configured by a pair of an upper transport roller installed on the upper side of the transport path 18 and a lower transport roller installed on the lower side of the transport path 18, and transports the banknotes being transported in the transport direction. .

  The sensor 11 includes a light emitting unit 11 b disposed below the transport path 18 and a light receiving unit 11 a disposed above the transport path 18. The light emitting unit 11b outputs the transmitted light toward the light receiving unit 11a, and the light receiving unit 11a receives the transmitted light. The light receiving unit 11a outputs a sensor output signal 12 indicating a pattern of received transmitted light. In general, there are various sensors such as an optical image sensor and a magnetic sensor as sensors used in the identification device, but various conventionally known sensors can be used.

  The identification controller 13 discriminates the authenticity of the banknote by analyzing the sensor output signal 12 described above. The identification control unit 13 not only processes the sensor output signal 12 but also corrects the output of the sensor 11 in order to correct the output of the sensor 11, an identification control program 151 stored in a CPU (Central Processing Unit) 14 or a nonvolatile storage device 15. , The non-volatile storage device 15 for storing the authenticity determination control program 152, the initial sensor correction value 153, the authenticity determination initial threshold value 154, the correction amount 155, and the initial determination block data 156, and the sensor output signal 12 are processed. And a memory 16 for temporarily storing the bill data 161 or storing a true / false determination threshold 162 and a fluctuation threshold ratio 163 during operation. Specific processing contents using these units will be described later. As will be described later, the identification control program 151 has a function of correcting the output of the sensor 11 and a function of changing the authenticity determination threshold value. It is governed by the Lord.

  In FIG. 1, the banknote is transported at a predetermined speed in the direction of the arrow by the transport roller 10 and passes through the sensor 11. Before the banknote is transported so as to obtain a certain output in advance, Since the output is corrected, the feature of the banknote can be read. Thereafter, the sensor output signal 12 output according to the characteristic of the banknote read by the sensor 11 is processed using the CPU 14 and the memory 16 as banknote data, and is compared with the authenticity determination threshold value 162 to determine the authenticity determination control program 152. Authenticates banknotes.

  Next, a method for correcting the output of the sensor 11 will be described with reference to FIGS. 2, 3, 4, and 5. FIG. 2 is a diagram illustrating an example of the configuration of the sensor 11. As shown in FIG. 2, the sensor 11 is configured as a line sensor 20 having a plurality of elements (here, n elements) arranged in a line. In the line sensor 20, elements are arranged side by side in the main scanning direction orthogonal to the transport direction in FIG. Alphanumeric characters (01 to n) shown in FIG. 2 indicate numbers for identifying elements. Each element of the line sensor 20 outputs a sensor output signal 12 that reacts to the characteristics of the bills that have been conveyed.

  As a sensor correction procedure, first, as shown in FIG. 3, the identification unit control program 151 outputs the sensor output after the initial correction so as to eliminate the variation of each element of the line sensor 20 during the production of the paper sheet identification apparatus 1000. 21 corrects each element so that a certain output is obtained. Then, the identification unit control program 151 stores the initial correction value as the initial correction value 153 in the nonvolatile recording device 15 in the identification control unit 13.

  FIG. 3 is a diagram illustrating an image of the sensor output signal 12 output from the sensor 11 when the paper sheet identification apparatus 1000 is produced. In FIG. 3, the vertical axis indicates the sensor output value, and the horizontal axis indicates the detection position (each element) in the main scanning direction. Thereafter, when the paper sheet identification device 1000 is in operation, the identification unit control program 151 reads the initial correction value 153 stored in the nonvolatile recording device 15 before the banknote is conveyed, and sends the correction signal 17 to the sensor 11. As described above, by adopting a mechanism in which the sensor output 21 after the initial correction is equivalent in each element, it is possible to read the characteristic data of the banknote determined every time. Such correction includes, for example, light amount correction on the light source side and light reception sensitivity correction on the light receiving element side when the sensor 11 is an optical image sensor. Since this is applicable, it will not be shown in detail here.

  FIG. 4 is a diagram illustrating an image of the sensor output signal 12 output from the sensor 11 after the paper sheet identification apparatus 1000 is operated. As shown in FIG. 4, even when the sensor output signal 12 is reduced as the sensor output 22 before operation correction due to the output degradation of the sensor 11 after operation, the identification unit control program 151 has a certain fixed value. Correct the output. Specifically, the identification unit control program 151 corrects the sensor output 23 after operation correction so that an output equivalent to the sensor output 21 after initial correction is obtained. The identification unit control program 151 records the correction amounts (b1, b2,..., Bn) for each element at this time as the correction amount 155 shown in FIG. As will be described later, the correction amount 155 is recorded in a table (correction amount table) as shown in FIG. The identification unit control program 151 records the correction amount in the correction amount table each time correction is performed, records the past correction amount in a history format, and a statistical amount (for example, an average value) determined using these correction amounts. Is calculated and updated. As will be described later, the correction amount history recorded in the correction amount table (for example, the number of corrections such as the current time, the previous time, and the previous time) can be arbitrarily determined.

  FIG. 5 is a diagram illustrating an example when a foreign object is present in the line sensor 20 illustrated in FIG. 2. In the example shown in FIG. 5, the case where the foreign substance 30 exists in the element 03 portion among the elements constituting the line sensor 20 is shown. In the paper sheet identifying apparatus 1000, there is a case where foreign matters such as dust are also transported together in the banknote transport path 18 and then fall on the banknote transport path 18 at a site where the sensor 11 is disposed. Even in this case, as described above, the identification unit control program 151 corrects the sensor 11 to have a constant output when the paper sheet identification apparatus 1000 is in operation. Specifically, the identification unit control program 151 corrects the sensor output 23 after operation correction so that an output equivalent to the sensor output 21 after initial correction can be obtained in the presence of foreign matter.

  FIG. 6 is a diagram illustrating how the output of the line sensor 20 is corrected when the foreign matter 30 is present in the line sensor 20 as described above. As shown in FIG. 6, since foreign matter exists in the element 03, in order to make the output of the sensor 11 constant like the sensor output 23 after operation correction, the element 03 in which the foreign matter 30 is present. It is necessary to increase the correction amount of the sensor output 22 before operation correction only for the part.

  FIG. 7 is a diagram illustrating a correction amount for the line sensor 20 in which the foreign object 30 is present. The identification unit control program 151 corrects the output of each element in order to keep the output of the sensor 11 constant, but as shown in FIG. 7, only the element 03 where the foreign object 30 exists is corrected for the output of the sensor 11. 31 becomes larger. If the operation is continued in this state, the sensor output as before can be obtained when the foreign object 30 is present. However, for example, when the foreign object 30 has flowed to another part in accordance with the banknote transport operation in the same way as when the banknotes are transported after being transported, the identification unit control program 151 is: Since the correction is performed with the correction amount 31 in consideration of the foreign matter, the output of the portion (element 03 in the example shown in FIG. 7) is excessively corrected. Therefore, when the characteristic data of the bill is read, the output value is different from the original sensor output 21 after the initial correction.

  As described above, if the state changes from the presence of the foreign matter 30 to the absence of the foreign matter 30, the correction for the output of the sensor 11 becomes excessive, which causes a wrong determination of a bill. Therefore, in the present embodiment, in consideration of natural degradation of the sensor 11, a certain range is provided for the output value of the sensor 11 after correction, and the authenticity determination control program 152 outputs within that range, as will be described later. When the value is settled, it is determined that the bill is a genuine note.

  FIG. 8 is a diagram showing the relationship between the above-described corrected output value and width (true / false determination threshold). In the example shown in FIG. 8, the authenticity of a banknote is determined using an upper limit threshold 40 and a lower limit threshold 41 as thresholds that are conceptually easy to understand for the output value of the sensor 11 that has read the feature data of the banknotes. explain. The true / false determination control program 152 sets a predetermined threshold value (for example, an upper limit value 40 and a lower limit value 41) for each output information obtained from various sensors of the banknote recognition apparatus 1000, and if within the threshold value range, It is determined as a genuine ticket, and if it is outside the threshold range, it is determined as a fraudulent ticket. In the present embodiment, description will be given by taking an example of the element 03 where the foreign material 30 exists.

  As the authenticity determination threshold 162 stored in the memory 6, the identification unit control program 151 sets an upper limit threshold 40 and a lower limit threshold 41 that are stored in advance in the nonvolatile storage device 15 as the authenticity determination initial threshold 154. And the authenticity determination control program 152 is the characteristic of the banknote conveyed, if the sensor 11 is correct | amended so that an output may become fixed by the identification part control program 151 at the time of operation of the paper sheet identification device 1000. By comparing the output of the sensor 11 corresponding to the above and the above-described upper limit threshold 40 and lower limit threshold 41 and determining whether or not the output is included in the authenticity determination threshold range 42, the authenticity of the bill Can be accurately determined.

  However, as shown in FIG. 5 to FIG. 7, when the output of the sensor 11 is corrected in a state where the foreign matter 30 exists in the element 03, when the foreign matter 30 no longer exists, only that portion is included. It will be in the state of overcorrection. FIG. 9 is a diagram illustrating a state in which overcorrection is performed on such a sensor 11. As shown in FIG. 9, the corrected sensor output 23 during operation is in an overcorrection state only at the element 03 where the foreign object 30 exists, and is out of the true / false determination threshold range 42. Will mistakenly discriminate what is supposed to be a genuine ticket as a fraudulent ticket.

  For this reason, the identification unit control program 151 changes the authenticity determination threshold 162 (upper limit threshold 40 and lower limit threshold 41) in the element 03 where the foreign object 30 exists (that is, to partially relax the threshold) By performing the process of changing the value, a mechanism is provided whereby the authenticity determination control program 152 can correctly determine the correct bill even after the foreign object 30 no longer exists. Whether or not the authenticity determination threshold 162 is changed from the value of the authenticity determination initial threshold 154 depends on whether the identification unit control program 151 has corrected the output of the sensor 11 during operation due to the influence of the foreign object 30 in the past. It is determined by determining whether or not the change is abrupt compared to the correction amount.

  FIG. 10 is a diagram illustrating an example of the configuration of the correction amount table. The correction amount table stores the correction amount for the output of each element constituting the sensor 11 in a history format for each element. As shown in FIG. 10, the correction amount table includes a number for identifying each element arranged in the main scanning direction, a variation threshold ratio indicating the degree of change in the correction amount for each element, and the latest and the past. The correction amount of the sensor 11 is stored in association with each element.

  In the example shown in FIG. 10, the sensor 11 is composed of n elements from elements 01 to n, and the correction amount for the output from each element is g1, g2,. This indicates that it was gn. Similarly, j1, j2,..., Jn in the order from the element 01 in the previous time, k1, k2,... Kn in order from the element 01 in the previous time, and m1 in order from the element 01 in the previous time. , M2,... Mn.

The identification unit control program 151 calculates a statistical value (for example, an average value) of the correction amount with reference to the past record of the correction amount of each element, and the current correction amount and the statistical value until the previous time are calculated. In comparison, it is determined whether or not there is a significant change. If the identification unit control program 151 determines that the current correction amount has changed significantly compared to the statistical value up to the previous time, the fact that there is a sudden foreign object in the element causes the output of the element to It is determined that correction has been performed, and the true / false determination threshold 162 for the element is changed. For example, the identification unit control program 151 determines that the correction amount of the output of the sensor 11 is corrected in the past when the output value of the sensor 11 after correction by the current correction amount has changed to an extent that does not satisfy the authenticity determination threshold 162. It is also possible to determine that the amount has changed suddenly compared to the amount, and to change the authenticity determination threshold 162 according to the current correction amount.

  Note that a specific value such as how much the correction amount changes compared with the statistical value up to the previous time and the true / false determination threshold 162 is changed is influenced by the output characteristics of the sensor 11, etc. It is not specified here. However, if the sensor 11 is purely deteriorated, the correction amount is gradually changed. If the influence is due to foreign matter, the correction amount is abruptly changed, so that determination is easy.

  For example, if the previous correction amount j3 of the element 03 and the previous correction amount k3 are relatively close values, and the previous correction amount m3 is extremely smaller than these values, It can be determined that the output of the element has been corrected in the presence of foreign matter. On the other hand, when the previous correction amount j3, the previous correction amount k3, and the previous correction amount m3 of the element 03 are close to each other and gradually increase, the deterioration of the element gradually proceeds. Therefore, it can be determined that the correction amount has increased.

The change amount of the authenticity determination threshold 162 may be, for example, a change of the threshold for each element in accordance with the fluctuation rate of the correction amount as in the following equation.
True / false judgment threshold after change (i) = initial judgment threshold (i) × (1 + variation threshold ratio (i))
Fluctuation threshold ratio (i) = (current correction amount (i) −statistics up to previous time (i)) ÷ maximum correction amount
Here, (i) is the element number. In this way, the identification unit control program 151 changes the authenticity determination threshold 162 according to the correction amount, so that the authenticity determination control program 152 determines that it is genuine. It is no longer possible to mistakenly identify where to be a fraudulent ticket.

  FIG. 11 is a diagram illustrating a state in which the identification unit control program 151 changes the authenticity determination threshold 162 according to the correction amount. As shown in FIG. 11, after the output of the sensor 11 is corrected in a state where the foreign matter 30 exists in the element 03, when the foreign matter 30 no longer exists, only that portion is over-corrected. End up. However, the identification unit control program 151 changes only the true / false determination threshold 162 of the element 03 where the foreign object 30 exists so as to relax the value according to the correction amount (in order to increase the upper limit in FIG. 11). Therefore, the post-correction sensor output 23 during operation does not fall outside the range of the authenticity determination threshold range 42, and the authenticity determination control program 152 can determine the bill as a genuine note as it is originally.

  In the description so far, in the case where the correction amount for the output of each element of the sensor 11 has changed abruptly compared to the past statistical value, the identification unit control program 151 determines that the existing foreign matter is It was determined that the location no longer exists due to movement or the like, and the threshold was changed according to the correction amount. In this case, the line sensor 20 includes an element whose correction amount is increased due to the influence of the foreign matter and an element which is not affected by the foreign matter and is corrected based on the original correction amount. In the identification of banknotes, when the sensor output signal 12 in each element matches the value of the corresponding part of the predetermined printing pattern, the banknote is determined as a correct banknote, which element is affected by foreign matter Is very important in understanding the characteristics of the bill.

  For this reason, below, each element which comprises the line sensor 20 is classified into the block (determination block) matched with the printing pattern of a banknote, and the importance in a printing pattern with respect to the classified determination block Weighting according to. For example, a judgment block in a characteristic part of a banknote (for example, an important part including a face or a monetary amount) is weighted so as to be a high point, and a part that is relatively difficult to become a characteristic of a banknote (for example, only a background pattern of a banknote) A case will be described in which a banknote is identified with high accuracy by weighting the determination block in the included portion) so as to be a low point.

  FIG. 12 is a diagram illustrating a state in which each element of the line sensor 20 is classified into a determination block for elements included in a predetermined range in the main scanning direction. As shown in FIG. 12, each element of the line sensor 20 is divided into a plurality of determination blocks in the main scanning direction. In the example shown in FIG. 12, element 00 to element 03 are determined in determination block A, element 04 to element 06 are determined in determination block B, element 07 to element 08 are determined in determination block C, and element n-3 to element n are determined. The remaining element is divided into a block N and a determination block X.

  The identification unit control program 151 refers to initial determination block data 156 (described later) stored in advance in the nonvolatile storage device 15 for each denomination, and true / false determination in each determination block is true (sensor output signal of each element). When it is determined that 12 is within the range of the true / false determination threshold 162, that is, a correct note, a point (weighting determination value for the determination block) corresponding to the determination block is set, and the true / false determination is false (each element) If it is determined that the sensor output signal 12 is out of the range of the authenticity determination threshold 162, that is, a fraudulent ticket), the point corresponding to the determination block is left. And the identification part control program 151 adds together the value of the point of each determination block, and if it is more than a predetermined value as a whole, this banknote will be determined comprehensively and will be finally determined as a correct bill.

  FIG. 13 is a diagram illustrating an example of the initial determination block data 156 described above. As illustrated in FIG. 13, the initial determination block data 156 stores the above-described determination blocks, ranges indicating elements included in each determination block, and points assigned to the determination blocks in the range in association with each other. Data. In the example shown in FIG. 13, 50 points are awarded to the decision block A, 15 points are given to the decision block B, 20 points are given to the decision block C, and 5 points are given to the decision block X. The determination block N is assigned 10 points, and is set to be 100 points as a whole. In this example, it can be seen that the determination block A is an important block having a large banknote feature.

  In the present embodiment, the identification unit control program 151 is true for each block of a plurality of determination blocks divided for each range of elements in the main scanning direction, because the characteristics of the banknotes differ from banknote to banknote and from part to part. When false determination is performed and the results are added together, the authenticity of the entire banknote is determined (overall determination), and when one of the elements included in each determination block is outside the range of the authenticity determination threshold 162 Judged to be fraudulent. However, you may determine with a fraudulent ticket according to the number of each element contained in each determination block. For example, the identification unit control program 151 sets a point of a block composed of five elements only when a plurality of elements (for example, two elements) are outside the range of the authenticity determination threshold 162. It is good also as not (none). In this way, by determining the fraudulent bill according to the number of elements included in each block, it is possible to determine the authenticity of the bill more flexibly.

  Note that the range of blocks to be determined and the weighting determination values for the blocks have initial values determined in advance according to the characteristics of the banknotes, but the characteristic detection positions change depending on the banknote transport positions, so that the determination blocks corresponding to the elements Is often variable. That is, the determination block and the weighted determination value itself are set and not changed before the first banknote is conveyed, but the position of the determination block to be identified (that is, the position of each element) is determined according to the position of the banknote being conveyed. ) Also changes, so the position of the determination block with respect to the element is reset every time a bill is conveyed.

  Furthermore, as described with reference to FIGS. 5 to 11, when the authenticity determination threshold 162 is changed, the identification unit control program 151 also changes the weighted determination value (point) set for each determination block as described above. Change according to the threshold ratio. FIG. 14 is a diagram illustrating an example in which the weighting determination value (point) of the determination block is changed according to the variation threshold ratio. The identification unit control program 151 subtracts the weighting determination value of the determination block corresponding to the element i of the variation threshold ratio (i) according to the variation threshold ratio by using the following formula, for example, and the determination corresponding to other than the element i Conversely, the block is changed to a value obtained by adding the weighted determination value to each determination block. In the example illustrated in FIG. 14, the weighting determination value of the determination block A having the element 03 is reduced by 10%, while the weighting determination values of other determination blocks are increased by 10%.

Weight determination value of determination block A corresponding to element i = initial weight determination value of determination block A × (1-variation threshold ratio (i))
Weight determination value of determination block x corresponding to other than element i = initial weight determination value of determination block x × (1 + variation threshold ratio (i))
Here, “x” is a determination block symbol other than element i (B, C,...)
As described above, the identification unit control program 151 blocks the banknotes when determining the authenticity of the entire banknote (overall determination), and determines whether each block is within the threshold after changing the weighting determination value. In addition, a mechanism for determining the authenticity of the banknote is provided by combining the results. Therefore, after correcting the line sensor 20 in a state where there is a foreign object before the operation, even if the foreign object disappears during the operation and the sensor output of the line sensor 20 changes, the bill is set according to the threshold set by relaxing the condition. Can be correctly determined. Further, the identification unit control program 151 finely blocks the banknote part, recognizes the part including the threshold value set by relaxing, and then changes the weighting (reliability) for the judgment, and then determines the authenticity of the banknote. By determining for each block, it is possible to reduce the erroneous determination rate due to the relaxed threshold.

  The correction process described in the present embodiment may be performed only once before the banknotes are conveyed (for example, when the paper sheet identification apparatus 1000 is activated), and thereafter each time the banknotes are conveyed. Since there is no need to do this, the processing load for each banknote can be reduced. Therefore, it is possible to provide an identification process that is not easily affected by a foreign object without imposing a load during a banknote identification process for each banknote (usually, a true / false determination process performed by the paper sheet identification apparatus 1000).

  In this embodiment, determination blocks are assigned to all the elements (i). However, only a certain range of elements (for example, a part important for determining the authenticity of a banknote such as a face or amount) is determined. May be assigned. By assigning the determination block in this way, it is possible to determine the authenticity of the banknote with simpler processing.

  Moreover, in this Embodiment, although the comprehensive determination of a banknote is made for the line sensor 20 as an example, there is no restriction | limiting in the number of the sensors made into the object of such comprehensive determination, Moreover, several comprehensive determination is carried out about one sensor. May be performed. At this time, it is not necessary to adopt a method of performing a correction process of changing the weighting threshold value for each determination block by relaxing the threshold value for all the comprehensive determinations. For example, for a certain sensor, the threshold value is not relaxed. The authenticity determination may be performed as it is.

  As described above, in the present embodiment, the identification control program 151 recognizes the presence of foreign matter when correcting the output of the sensor 11, changes (relaxes) the authenticity determination threshold 162 of the part where the foreign matter exists, Since a mechanism that can make a determination without change when there is / without is present and there is a high possibility of erroneous determination just by relaxing the authenticity determination threshold 162, the determination is divided into blocks for each part, and the authenticity determination control program 152 Then, comprehensive determination is made by adding points to each block. Then, the identification control program 151 changes the weighting determination value of each block so that the points are lowered and the points of the other blocks are increased in the blocks where there is a foreign object and the authenticity determination threshold 162 is relaxed. In other words, it can be judged as point equal reliability, the degree of influence on erroneous determination of banknotes can be reduced, correction considering the influence of sudden foreign matter can be realized, and true / false determination processing with a low error determination rate can be realized It becomes.

  In the above-described first embodiment, the paper sheet identification device has been described as having a single line sensor. However, for example, depending on the country, there are many counterfeit banknotes, or when counterfeiting is elaborate, or when there are many banknotes with high levels of dirt, it is necessary to more accurately determine the authenticity of the banknotes depending on the banknote circulation mode. There are cases. Therefore, in preparation for such a case, in this embodiment, not only one sensor but also the output information of a plurality of sensors is regarded as one group, and the determination of the correction processing influence of one sensor is made to the determination block of another sensor. As an authenticity determination, an example in which a plurality of sensor information is determined as one block will be described.

  FIG. 15 is a diagram illustrating a configuration of the paper sheet identifying apparatus 2000 according to the second embodiment. As illustrated in FIG. 15, the paper sheet identification device 2000 includes a sensor 2011 and a sensor 100 in addition to the same configuration as each component included in the paper sheet identification device 1000 according to the first embodiment. This is different from the paper sheet recognition apparatus 1000 in the first embodiment. In the following description, the same components as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted. The sensor correction processing described in FIGS. 2 to 11 is also the same as that in the first embodiment, and thus the description thereof is omitted.

  In FIG. 15, the paper sheet identification device 2000 shows that a plurality of sensor configurations are regarded as one determination block and the authenticity of the banknote is determined. In 1st Embodiment, the site | part which gathered each element which comprises one sensor (line sensor 20) is divided | segmented into several determination blocks by making into one unit, and a weighting determination value is set for every determination block, and it is a banknote. Overall judgment was made. However, in this Embodiment, the paper sheet identification device 2000 is performing the comprehensive determination of a banknote using a some sensor. The sensor 2011 and the sensor 100 are provided according to the characteristics of the bill. For example, the sensor 2011 is an image sensor, and the sensor 100 is a magnetic sensor. Although the case where two sensors are used is described below, it is of course possible to make a comprehensive determination using three or more types of sensors. Next, comprehensive determination using each sensor will be described.

  FIG. 16 is a diagram illustrating a state in which the paper sheet recognition apparatus 2000 comprehensively determines banknotes using a plurality of sensors. As illustrated in FIG. 16, in the paper sheet identification device 2000, a plurality of determination blocks are associated with the sensor 2011, a plurality of other determination blocks different from the sensor 2011 are associated with the sensor 100, and these A weighting judgment value is set for the whole. In the example shown in FIG. 16, there are four blocks of determination blocks Q, R, T, and U in the main scanning direction of each sensor, which is the same as the initial determination block data (FIG. 13) described in the first embodiment. In addition, the entire determination block of the two sensors is set to 100 points. In this example, it can be seen that the determination block Q is an important block having a large bill feature. As described above, by performing authenticity determination using a plurality of different sensors according to the characteristics of the banknote, it is possible to perform appropriate determination according to the part. For example, the sensor 2011 scans the image of the face portion to determine the authenticity of the portion, while the pattern portion is suitable for each part corresponding to each determination block of the banknote, such as reading a magnetic pattern by the sensor 100. A bill can be determined.

  As in the case of the first embodiment, the identification unit control program 151 determines whether the foreign substance is present in the determination block Q of the sensor 11 and the correction amount of the sensor 11 has changed abruptly. Are subtracted according to the fluctuation threshold ratio. On the other hand, the discriminator control program 151 changes the decision blocks (determination blocks R, T, U) to values obtained by adding the respective decision blocks to the weighted decision values. The setting of such weight determination values is the same as that described in the first embodiment.

  In this way, the determination blocks T and U are not sensors 2011, but are different sensors corresponding to different sensors 100. However, by defining them as one block as a whole, they are handled as the same comprehensive determination target, By changing the weighting determination value for each determination block across the sensors, it is possible to make a comprehensive determination of banknotes by associating the influence of foreign matter with information from a plurality of sensors.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of a certain embodiment can be replaced with the configuration of another embodiment, and another embodiment can be added to the configuration of a certain embodiment. In addition, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment. Moreover, although the example applied to the banknote identification device of ATM was described in the said Example, this invention is not only a banknote identification unit which identifies a banknote, but paper sheets other than a banknote (for example, a check, a securities, a game machine) The present invention can also be applied to an apparatus for handling bills and the like.

1000 2000 Paper sheet identification device 10 Conveyance roller 11 2011 Sensor 100 Sensor 12 Sensor output signal 13 Identification control unit 14 CPU
15 Non-volatile storage device 151 Identification control program 152 Authenticity determination control program 153 Initial sensor correction value 154 Authenticity determination initial threshold 155 Correction amount 156 Initial determination block data 16 Memory 161 Banknote data 162 Authenticity determination threshold 163 Fluctuation threshold ratio 17 Correction signal 18 bill conveyance path 20 sensor (line sensor)
21 Sensor output 30 after initial correction Foreign matter 31 Foreign matter correction amount 40 Upper threshold 41 Lower threshold 42 Authentication threshold range.

Claims (13)

A paper sheet identification device for determining the authenticity of a paper sheet,
A sensor for detecting characteristics of the paper sheet;
A storage unit for storing a determination threshold value for determining the authenticity of the paper sheet;
A correction unit that corrects the output of the sensor so that the output value is constant;
An identification control unit that changes the determination threshold in accordance with the changed correction amount when the current correction amount of the sensor output has changed abruptly compared to a past correction amount;
Using the determination threshold after the change by the identification control unit, a true / false determination unit that determines the authenticity of the paper sheet,
A paper sheet identification device comprising: The storage unit stores the past correction amount as a history,
The identification control unit calculates a statistical value of the correction amount based on the past correction amount stored in the history, and compares the calculated statistical value with the current correction amount to thereby output the sensor. To determine whether or not the current correction amount has changed abruptly compared to the past correction amount,
The paper sheet identification apparatus according to claim 1. The identification control unit calculates a change amount indicating a degree of changing the determination threshold based on the statistical value and the current correction amount, and changes the determination threshold according to the calculated change amount.
The paper sheet identification device according to claim 2 . When the sensor output value after the correction by the current correction amount has changed to a level that does not satisfy the determination threshold, the identification control unit makes the correction amount of the sensor output suddenly compared to the past correction amount. And change the determination threshold according to the current correction amount,
The paper sheet identification apparatus according to claim 1 . The storage unit stores the determination threshold as a certain range having an upper limit value and a lower limit value,
The identification determination unit changes the determination threshold according to the current correction amount when the output value of the sensor after correction by the current correction amount is not included in the range.
The paper sheet identification apparatus according to claim 1 . The sensor is a line sensor having a plurality of elements,
The determination threshold is stored for each element,
The correction unit corrects the output of the sensor for each element,
The identification control unit, for each element, when the current correction amount of the sensor output has changed abruptly compared to the past correction amount, change the determination threshold according to the changed correction amount,
The authenticity determination unit determines the authenticity of the paper sheet using the determination threshold value changed for each element.
The paper sheet identification apparatus according to any one of claims 1 to 5, wherein The storage unit further stores block data in which a block in which the paper sheet is divided into a plurality of parts and an importance point determined according to the characteristics of the paper sheet included in the part are associated with each other. ,
The authenticity determination unit determines whether the paper sheet is true or false for each block, and determines whether to assign the importance point to each part of the paper sheet based on the determination result for each block. Determining, based on the total value of the assigned importance points, comprehensively determining the authenticity of the paper sheet,
The paper sheet identification apparatus according to claim 1, wherein The identification control unit increases or decreases the point according to a change in the correction amount.
The paper sheet identification apparatus according to claim 7. The identification control unit assigns the importance point to a block for which the authenticity determination of the paper sheet is true, and assigns the importance point to a block for which the authenticity determination of the paper sheet is false. No ,
The paper sheet identification apparatus according to claim 7 or 8, wherein The block is composed of a plurality of elements,
The identification control unit does not give the importance point to the block when a plurality of the elements included in the block are outside the range of the determination threshold ,
The paper sheet identification device according to any one of claims 7 to 9. The block is set only in a portion showing an important characteristic of the paper sheet,
The paper sheet identification apparatus according to any one of claims 7 to 10. The paper sheet identification device includes a plurality of sensors provided according to characteristics of the paper sheet,
The identification control unit changes the determination threshold for each of the sensors,
The authenticity determination unit determines the authenticity of the paper sheet using the determination threshold value after being changed for each of the sensors.
The paper sheet identification device according to any one of claims 1 to 11, The storage unit further stores whole block data in which a whole block including each block of the plurality of sensors is associated with the importance point in the whole block,
The authenticity determination unit determines whether the paper sheet is true or false for each block, and determines whether to assign the importance point to each part of the paper sheet based on the determination result for each block. Determining, based on the total value of the assigned importance points for the entire block, comprehensively determining the authenticity of the paper sheet,
The paper sheet identification apparatus according to claim 12, wherein:

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