JP5227267B2 - Paper sheet fatigue discrimination device, banknote processing device, paper sheet fatigue discrimination method - Google Patents

Description

  The present invention relates to a technique for detecting a fatigued banknote.

  2. Description of the Related Art Various types of banknote processing apparatuses that can take in, store, and pay out banknotes of multiple denominations in various applications such as vending machines, game media lending machines at game halls, ticket vending machines, and money changers have been known. Yes. In this type of banknote handling apparatus, the following Patent Documents 1 to 5 propose techniques for detecting a fatigued banknote.

  Patent Document 1 below collects passing sound generated when a paper sheet passes through a conveyance path, separates an electrical signal of the collected passing sound into a low frequency component and a high frequency component, A technique for determining whether a paper sheet is normal or not based on the number of pulses of a high-frequency component when the component is present is disclosed.

  Patent Document 2 below discloses a technique for discriminating between correct bills and damaged bills based on the strength of frequency components unique to a bill among frequency components of sound generated when the bill is bent.

  Patent Document 3 below discloses a technique for discriminating between correct bills and damaged bills based on the strength of frequency components unique to bills among frequency components of sound generated when a bill is struck.

  Patent Document 4 below discloses an apparatus for measuring the rigidity of a paper sheet based on the level of noise contained in sound generated when a bill is bent. Patent Document 5 listed below discloses money and securities. A technique is disclosed that collects sound at the time of hitting, performs Fourier expansion on the frequency component of the collected sound, and identifies the authenticity by the most frequency components.

JP-A-11-53602 Japanese Patent Laid-Open No. 61-169983 JP-A-61-168084 JP 58-86436 A JP 2000-251108 A

  However, the techniques of the above cited references 1 to 5 require frequency analysis, noise component extraction processing, and the like, and corresponding circuit parts are required to perform these processes, which increases the size of the apparatus. Incurs increased costs.

  The present invention has been made in view of such circumstances, and is a paper sheet fatigue determination device that can accurately determine the fatigue state of a bill while avoiding or suppressing an increase in size and cost of the device, and a bill. It is an object of the present invention to provide a processing apparatus and a paper sheet fatigue discrimination method.

  According to the first aspect of the present invention, there is provided a sampling unit that samples a signal corresponding to a sound generated during conveyance of a paper sheet as sampling data a plurality of times, the sampling data, and a predetermined sampled before the sampling data A difference in data value between the first sampling data and a difference in data value between the sampling data and a predetermined sampling data sampled after the sampling data is calculated as a first amplitude difference and a second amplitude difference, respectively. A set of data composed of the calculation unit and the first and second amplitude differences calculated for one sampling data is plotted in a predetermined coordinate system, and the paper is based on the distribution of the plotted data. A paper sheet fatigue discrimination device including a discrimination unit for discriminating a fatigue state of a leaf.

  The invention according to claim 7 is a sampling step in which the sampling unit samples a signal according to a sound generated during conveyance of the paper sheet as sampling data a plurality of times, and an amplitude difference calculation unit includes the sampling data A difference in data value between predetermined sampling data sampled before the sampling data and a difference in data value between each sampling data and predetermined sampling data sampled after the sampling data are respectively set to a first value. And a calculation step for calculating as a second amplitude difference, and a determination unit plots a set of data composed of the first and second amplitude differences calculated for one sampling data in a predetermined coordinate system. Determine the fatigue state of the paper based on the distribution of the plotted data A paper sheet fatigue determination method and a determination step.

  As in the first and seventh aspects of the invention, the inventor calculates the difference between the data values of the respective sampling data and the predetermined sampling data sampled before and after the sampling data as the first and second amplitudes, respectively. The paper sheets based on a distribution obtained by plotting a set of data composed of the first and second amplitude differences calculated for one sampling data in a predetermined coordinate system as a difference. It was found that the fatigue state of paper sheets can be accurately determined by determining the fatigue state of the paper.

  In this case, in the inventions of the first and seventh aspects, the first method is not a process that causes an increase in the size and cost of the apparatus, such as a frequency analysis or a noise component extraction process, as in the prior art. A relatively simple calculation for determining the fatigue state of the paper sheet based on the calculation of the second amplitude difference and the distribution of a set of data composed of these amplitude differences in the predetermined coordinate system. The fatigue state of the paper sheet can be determined by the processing.

  According to a second aspect of the present invention, in the paper sheet fatigue determination apparatus according to the first aspect, the determination unit is a two-dimensional coordinate system in which the first amplitude difference and the second amplitude difference are set as coordinate axes, respectively. A set of data composed of the first and second amplitude differences respectively calculated for the respective sampling data, and the distribution of the data plotted in the two-dimensional coordinate system is determined in advance. The sheet is converted into a distribution represented by a polar coordinate system as a coordinate system, and the fatigue state of the paper sheet is determined based on the distribution of data plotted in the polar coordinate system.

  The invention according to claim 8 is the paper sheet fatigue determination method according to claim 7, wherein in the determination step, the determination unit is set with the first amplitude difference and the second amplitude difference as coordinate axes, respectively. Plotting a set of data composed of the first and second amplitude differences calculated for each of the sampling data in the two-dimensional coordinate system, and the determination unit plots in the two-dimensional coordinate system Converting the distribution of the obtained data into a distribution expressed in a polar coordinate system as the predetermined coordinate system, and the discriminating unit based on the distribution of the data plotted in the polar coordinate system And determining the fatigue state.

  According to the second and eighth aspects of the present invention, a distribution obtained by plotting a set of data composed of the first and second amplitude differences calculated for each sampling data in the two-dimensional coordinate system. Is converted into a distribution expressed in a polar coordinate system, and the fatigue state of the paper sheet is determined based on this distribution. Therefore, the fatigue state of the paper sheet can be determined by relatively simple calculation and processing. Can do.

  According to a third aspect of the present invention, in the paper sheet fatigue determination apparatus according to the first aspect, the determination unit is set with the first amplitude difference and the second amplitude difference as coordinate axes, respectively. A set of data composed of the first and second amplitude differences calculated for each of the sampling data is plotted on a two-dimensional coordinate system as a coordinate system, and plotted on the two-dimensional coordinate system. The fatigue state of the paper sheet is determined based on the data distribution.

  The invention according to claim 9 is the paper sheet fatigue determination method according to claim 7, wherein in the determination step, the determination unit is set with the first amplitude difference and the second amplitude difference as coordinate axes, respectively. Plotting a set of data composed of the first and second amplitude differences calculated for each of the sampling data in a two-dimensional coordinate system as the predetermined coordinate system; and the determination And a step of determining a fatigue state of the paper based on a distribution of data plotted in the two-dimensional coordinate system.

  According to the third and ninth aspects of the invention, the two-dimensional coordinate system is obtained by plotting a set of data composed of the first and second amplitude differences respectively calculated for the respective sampling data. Since the fatigue state of the paper sheet is determined based on the distribution, the fatigue state of the paper sheet can be determined by a relatively simple calculation and processing.

  According to a fourth aspect of the present invention, in the paper sheet fatigue determination device according to any one of the first to third aspects, the determination unit includes a plurality of the predetermined coordinate systems in a predetermined form. The number of data plotted in each divided area is detected for each divided area, and the number of data detected for each divided area is made to correspond to a plurality of fatigue states for each divided area. And a plurality of reference values corresponding to the divided region among a plurality of reference values determined in advance, and the number of detected data corresponds to the closest reference value among the plurality of reference values to be compared Is determined as the fatigue state of the paper sheet.

  A tenth aspect of the present invention is the paper sheet fatigue determination method according to any one of the seventh to ninth aspects, wherein in the determination step, the determination unit determines the predetermined coordinate system in advance. Detecting for each divided region the number of data plotted in each divided region obtained by dividing the plurality of regions into a plurality of regions, and the determination unit determines the number of data detected for each divided region. , Comparing with a plurality of reference values corresponding to the divided region among a plurality of reference values predetermined corresponding to a plurality of fatigue states for each divided region, the number of the detected data is a plurality of the comparison target And determining a fatigue state corresponding to the closest reference value among the reference values as a fatigue state of the paper sheet.

  According to the fourth and tenth aspects of the present invention, the number of data plotted in each divided area obtained by dividing the predetermined coordinate system into a plurality of areas in a predetermined form is determined for each divided area. And a plurality of reference values corresponding to the divided areas among a plurality of reference values determined in advance corresponding to a plurality of fatigue states for each divided area, In comparison, the fatigue state corresponding to the closest reference value among the plurality of reference values of the comparison target is determined as the fatigue state of the paper sheet. The fatigue state of the paper sheet can be determined by simple calculation and processing.

  According to a fifth aspect of the present invention, in the paper sheet fatigue determination device according to any one of the first to third aspects, the determination unit is configured to perform the pre-preparation for a plurality of boundary setting paper sheets prepared in advance. The number of data plotted in each divided area obtained by dividing a predetermined coordinate system into a plurality of areas in a predetermined form is detected for each divided area, and the number of data in each divided area is expressed as a coordinate axis. In the determination coordinate system set as, coordinates indicating the number of data in each of the divided areas are respectively obtained, and a plurality of coordinates among the obtained coordinates on the determination coordinate system are set as coordinates for deriving the boundary. Then, after obtaining a boundary based on the coordinates for deriving the boundary and dividing the region of the determination coordinate system into a plurality of regions based on the boundary, the predetermined coordinate system is determined for the sheet to be determined. The number of data plotted in each divided area divided into a plurality of areas in a predetermined form is detected for each divided area, and on the determination coordinate system corresponding to the number of plotted data The coordinates of the sheet are detected, it is detected which of the plurality of areas divided by the boundary belongs to, and the fatigue state of the paper sheet is determined based on the detection result It is.

  The invention according to claim 11 is the paper sheet fatigue determination method according to any one of claims 7 to 9, wherein the determination step includes a plurality of boundary setting paper sheets prepared in advance by the determination unit. Detecting the number of data plotted in each divided area obtained by dividing the predetermined coordinate system into a plurality of areas in a predetermined form for each divided area; and A determination coordinate system in which the number of data in each divided region is set as a coordinate axis, respectively, a step of obtaining coordinates indicating the number of data in each divided region, and the determination unit includes the obtained determination A step of setting a plurality of coordinates as coordinates for deriving the boundary among the coordinates on the coordinate system, and the determination unit obtains a boundary based on the coordinates for deriving the boundary, and Dividing the region of the determination coordinate system into a plurality of regions, and the determination unit then converts the predetermined coordinate system into a plurality of regions in a predetermined form for the paper sheet to be determined A step of detecting the number of data plotted in each of the divided areas obtained by the division for each divided area; and the determination unit calculates coordinates on the determination coordinate system corresponding to the number of plotted data. And determining which of the plurality of regions divided by the boundary the coordinate belongs to, and determining a fatigue state of the paper based on the detection result Is.

  According to the fifth and eleventh aspects of the present invention, in the determination coordinate system in which the number of data in each divided area is set as a coordinate axis, a plurality of coordinates among the coordinates indicating the number of data in each divided area are set. Set as the coordinates for deriving the boundary, obtain the boundary based on the coordinates for deriving the boundary, and the coordinates corresponding to the number of data in each divided area detected for the paper sheet to be determined are divided by the boundary Since the fatigue state of the paper sheet is determined on the basis of which area of the determined areas belongs, it is possible to accurately determine the fatigue state of the paper sheet.

  The invention according to claim 6 is that the paper sheet is a banknote, a slot for inserting a banknote, a paper sheet fatigue determination device for determining a fatigue state of a banknote inserted from the slot, and 6. A banknote processing apparatus comprising: a storage unit that stores the banknotes sorted according to fatigue states based on a determination result by a paper sheet fatigue determination apparatus, wherein the paper sheet fatigue determination apparatus is any one of claims 1 to 5. It is the banknote processing apparatus used as the paper sheet fatigue discrimination apparatus of description.

  According to this invention, when a function for determining the fatigue state of a paper sheet is mounted on the banknote handling apparatus, it is possible to prevent the banknote handling apparatus from becoming large or increasing costs due to the mounting of the function. it can.

  According to the present invention, it is possible to accurately determine the fatigue state of a paper sheet. In addition, it is not a process that causes an increase in the size and cost of the apparatus such as frequency analysis and noise component extraction processing, but a set of computations of the first and second amplitude differences and these amplitude differences. Since the fatigue state of the paper sheet is determined based on the distribution of the data in the predetermined coordinate system, the fatigue state of the paper sheet can be determined by relatively simple calculation and processing. Therefore, it is possible to prevent or suppress the increase in size and cost of the apparatus.

It is a figure which shows the internal structure of one Embodiment of the banknote processing apparatus which concerns on this invention. It is a figure which shows the internal structure of one Embodiment of a banknote processing apparatus. It is a figure which shows the external appearance of a banknote processing apparatus. It is a figure which shows the external appearance of a banknote processing apparatus. It is a block diagram which shows the electrical structure of a banknote processing apparatus. It is explanatory drawing of the sampling operation | movement by a sampling part. It is explanatory drawing of the process by a plot part. It is explanatory drawing of the process by a plot part. It is a figure which shows an example of distribution of the plot point in the two-dimensional coordinate system about all the sampling data. (A) shows the signal waveform of the output signal (sound signal) of the microphone that collected the sound emitted during the transportation of the old bill, and (b) collected the sound emitted during the transportation of the new bill. It is a figure which shows the signal waveform of the output signal (sound signal) of a microphone. The polar coordinate system is divided in increments of π / 2, a divided region 1 having angles “0” to “π / 2”, a divided region 2 having angles “π / 2” to “π”, and angles “π” to “3π. / 2 ”and four divided regions 4 having angles“ 3π / 2 ”to“ 2π ”are set, and each plot point in the two-dimensional coordinate system shown in FIG. It is the figure which showed distribution when it represents with. It is a figure which shows the example of an aspect of distribution of the plot point about the old bill and new bill in a polar coordinate system. It is an example of the table memorize | stored in the reference value memory | storage part. It is a flowchart which shows the flow of the banknote at the time of money_receiving | payment by a banknote processing apparatus. It is a flowchart which shows the flow of the fatigue state identification process of a banknote. It is explanatory drawing of the modification of the fatigue state identification process of a banknote. It is a figure which shows an experimental result when the experiment which identifies the fatigue state of the predetermined number of banknotes prepared beforehand is performed with the banknote processing apparatus which concerns on this invention.

  Hereinafter, the embodiment of the bill processing device concerning the present invention is described. 1 and 2 show the internal structure of an embodiment of the banknote handling apparatus according to the present invention, and FIGS. 3 and 4 show the external appearance of the banknote handling apparatus.

  As shown in FIGS. 1-4, the banknote processing apparatus 1 has the casing 1a formed in the box shape of the predetermined magnitude | size which can accommodate each unit 2,3,4A-4C mentioned later, The casing 1 a includes a box-shaped casing main body 11 having an open front side (the right side in FIG. 1) and a door 12 that closes the front surface of the casing main body 11. In the upper part of the door 12 on the front surface of the casing 1a, an opening 14 for inserting bills and an opening 15 for dispensing are disposed.

  Inside the casing 1a, a deposit / withdrawal unit 2 located at the uppermost part, a base unit 3 located at the lowermost part, and one or a plurality of stages (in the illustrated example) located between these units 2,3. Three-stage intermediate units 4A to 4C are provided. Each intermediate unit 4A to 4C and base unit 3 stores bills by denomination. For example, the upper unit 4A of the intermediate unit has a thousand yen bill, the middle unit 4B has a five thousand yen bill, and the lower unit. Ten thousand yen bills are stored in 4C, respectively, and bills with high fatigue (old bills described later) are stored in the base unit 3.

  Further, if necessary, an auxiliary unit 5 for increasing the bill storage space is arranged above any one or a plurality of intermediate unit, and in the example shown, the auxiliary unit 5 is arranged on the intermediate unit 4A. Yes.

  The deposit / withdrawal unit 2, the base unit 3, and the intermediate units 4A to 4C can be separated from each other and can be attached to and detached from the casing 1a. A supported portion 17 provided on one side of each of the units 2, 3, 4A to 4C is coupled to a slide guide 16 provided on one side of the casing 1a so as to be slidable in the front-rear direction. Thus, the units 2, 3, 4A to 4C are supported in a cantilever state in a state in which the units 2, 3, 4A to 4C can be individually pulled out forward with respect to the casing 1a.

  As shown in FIG. 4, a control board 100 and a power supply 105 including a main CPU board 101, a sub CPU board 102, and the like are provided on the side of the casing 1 a. On the other hand, each unit 2, 3, 4A-4C is electrically connected via a detachable connector.

  The deposit / withdrawal unit 2 includes a bill introduction mechanism 21 for introducing a bill from the insertion port 20a into a frame 20 having an insertion port 20a and a payout port 20b, and a banknote derivation mechanism 23 for guiding the bill to the payout port 20b. And the transport mechanism 29 are accommodated in the upper part of the casing 1a in a state in which the insertion port 20a and the outlet 20b protrude from the openings 14 and 15 of the casing 1a.

  The bill introduction mechanism 21 has an identification device 22 for identifying the authenticity and denomination of the bill in the vicinity of the insertion slot 20a, and the banknote taken from the insertion port 20a via the identification device 22 is downward in the rear part of the unit 2. It has a bill introduction path 210 that guides it so that it is directed, and feed rollers 211 and 212 arranged on the upstream and downstream sides of the bill introduction path 210, a guide roller 213 arranged in the middle of the bill introduction path 210, etc. It has. The rollers 211, 212, 213, and 214 are driven by a motor 215 via a transmission mechanism 216 such as a belt.

  The banknote derivation mechanism 23 includes a mechanism that pays out banknotes to the payout opening 20b in accordance with a payout command, and a mechanism that rejects illegal banknotes and the like, and a payout reject disposed at a height corresponding to the payout opening 20b. Feeding belt device 24, a temporary storage unit 25 composed of a space above the belt device 24, a guide device 26 for guiding banknotes to the temporary storage unit 25, and a temporary storage unit 25 on the belt device 24. And a reject chamber 28 formed in a space below the belt device 24. The front surface of the reject chamber 28 can be opened by a door 280, and a lock 281 is provided on the door 280.

  The base unit 3 includes a banknote storage unit 31, a transport mechanism 32 that transports banknotes behind the banknote storage unit 31, a transport motor 33 that is a drive source of the transport mechanism 32, a transport mechanism 32, and banknote storage. A take-out / feeding mechanism 34 that takes in and out banknotes from / to the unit 31, a banknote stacking mechanism 35 that stacks banknotes in the banknote storage unit 31, and a drive mechanism 36 that drives the banknote stacking mechanism 35 are provided. ing.

  The banknote storage unit 31 includes both side plates, a bottom plate, a front door 310 (see FIG. 2), and the like, and is formed to have a space in which banknotes can be stored in an accumulated state. The door 310 is provided with a lock 311. A bill support table 312 is provided in the bill storage unit 31 at a predetermined height position.

  Each of the intermediate units 4A to 4C has the same structure, and each includes a banknote storage unit 41 and a transport mechanism 42 that transports banknotes in the range from the upper end to the lower end of the unit behind the banknote storage unit 41. In addition, it has a take-out / feeding mechanism 44 for taking in and feeding out banknotes between the transport mechanism 42 and the banknote storage unit 41, and a banknote stacking mechanism 45 for stacking banknotes in the banknote storage unit 41.

  The banknote storage part 41 is composed of both side plates, a bottom plate, a door 410 with a lock 411 on the front side (see FIG. 2), and the like, like the banknote storage part 31 of the base unit 3.

  In addition, the auxiliary unit 5 is provided with a storage space increasing portion 51 that communicates with the bill storage portion 41 of the unit 4A located below, and a transport mechanism 52 is provided behind the storage space increasing portion 51. Although not shown in detail, the transport mechanism 52 includes a pair of upper and lower rollers as well as the transport mechanism 42 of the intermediate unit 4A to 4C, and includes a gear provided on each roller shaft and one of the upper and lower rollers. A transmission belt is provided between pulleys provided on the roller shaft, and an intermediate transmission gear that meshes with a gear provided on the upper one roller shaft. The rollers interlock with each other, and the driving force can be transmitted from the lower unit to the upper unit while the driving force can be transmitted to the upper unit.

  Next, the electrical configuration of the banknote handling apparatus 1 shown in FIGS. 1 to 4 will be described. FIG. 5 is a block diagram showing an electrical configuration of the banknote handling apparatus 1. The same members as those shown in FIGS. 1 to 4 are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIG. 5, the banknote handling apparatus 1 includes a microphone 501, a banknote insertion sensor 502, a banknote passage sensor 503, and a control unit 600 in addition to the deposit / withdrawal unit 2, the base unit 3, and the intermediate unit 4 </ b> A to 4 </ b> C. .

  The microphone 501 converts sound into an electrical signal (analog signal), and collects sound generated during the conveyance of banknotes. The microphone 501 is installed in or near the conveyance path where the bills whose authenticity and denomination are identified by the identification device 22 are conveyed, and in this embodiment, as shown in FIG. The microphone 501 is installed in the vicinity of the roller 214 provided in the transmission mechanism 216.

  As shown in FIG. 1, the bill insertion sensor 502 is installed in the vicinity of the bill insertion slot 20 a and detects insertion of a bill into the opening 14. The bill insertion sensor 502 includes, for example, a pair of reflection type light projecting and receiving devices, and when the bill to be conveyed enters the detection position, the light output from the projector is reflected by the bill and received by the light receiving device. Is done. The bill insertion sensor 502 outputs a light reception signal (ON signal) to the control unit 600 while the light receiver receives reflected light from the bill. The rise timing and fall timing of the ON signal output from the bill insertion sensor 502 are used to determine the start and stop timing of the operation of the motor or the like provided in the bill introduction mechanism 21.

  As shown in FIG. 1, the bill passage sensor 503 is installed in the vicinity of the roller 214 provided in the transmission mechanism 216 and in the vicinity of the microphone 501 (the position downstream of the microphone 501). The passage of the banknote at the set detection position is detected. The bill passage sensor 503 has a configuration similar to that of the bill insertion sensor 502, and outputs a light reception signal (ON signal) to the control unit 600 while the light receiver receives reflected light from the bill. . The rise timing and fall timing of the ON signal output from the bill passage sensor 503 are used to determine the start and stop timings of the sound collection operation of the microphone 501.

  The control unit 600 includes a CPU (Central Processing Unit) (not shown), a ROM (Read Only Memory) that stores a program that defines the operation of the CPU, and a function and work area for temporarily storing data. The microcomputer comprises a RAM (Random Access Memory) or the like having the above functions and controls the banknote processing apparatus 1 as a whole. The control unit 600 includes circuit components on the main CPU board 101 and the sub CPU board 102 installed on the control board unit 100.

  By the way, the banknote processing apparatus 1 according to the present embodiment is intended for banknotes whose authenticity and denomination have been identified by the identification device 22, and fatigue (degree of paper sheets or wrinkles) is small, and the degree of tension or waist is small. Whether the bill is a large bill (hereinafter referred to as a new bill) or a bill with a large degree of fatigue or tension (hereinafter referred to as an old bill) The old bill is extracted from the bills inserted into the device 1 and stored inside the device 1 so that the old bill is not used again.

  In order to realize this function, the control unit 600 includes a sound collection control unit 601, a sampling unit 602, an amplitude difference calculation unit 603, a plot unit 604, a coordinate system conversion unit 605, and a plot number counting unit for each region. 606, a reference value storage unit 607, and a determination unit 608.

  The sound collection control unit 601 controls the sound collection operation of the microphone 501, and the rising timing of the output signal of the banknote passage sensor 503 from OFF to ON (the leading edge of the banknote passes through the detection position of the banknote passage sensor 503). Based on the timing), the sound collection operation by the microphone 501 is started, and the output signal of the bill passage sensor 503 falls from ON to OFF (the detection position of the bill passage sensor 503 is determined by the trailing edge of the bill). The sound collection operation by the microphone 501 is stopped based on the timing of the passage (corresponding to the start timing).

  FIG. 10A shows the signal waveform of the output signal (sound signal) of the microphone 501 that collects the sound emitted during the transportation of the old bill, and FIG. 10B is emitted during the transportation of the new bill. It is a figure which shows the signal waveform of the output signal (sound signal) of the microphone 501 which collected the sound. As can be seen from FIGS. 10A and 10B, the amplitude of the signal waveform is larger in the case of the new bill than in the old bill. On the other hand, in the case of an old bill, the signal waveform changes smoothly (amplitude increase / decrease mode is small) compared to a new bill.

  As shown in FIG. 6, the sampling unit 602 samples the analog signal S output from the microphone 501 at a constant sampling period T (for example, T = 1/5000 seconds). Hereinafter, the sampled data is referred to as sampling data. When the length in the banknote transport direction is, for example, 16 cm, the banknote transport speed is 8 cm / sec, and sampling is performed at a sampling period of 1/5000 (sec), 10000 (pieces) of sampling data is obtained per banknote. It will be.

  The amplitude difference calculation unit 603 calculates, for each sampling data acquired by the sampling unit 602, a data value difference from the previous sampling data and a data value difference from the next sampling data. Is. For example, when focusing on the sampling data indicated by the arrow Q1 in FIG. 6, the amplitude difference calculation unit 603 calculates the difference between the data value of the sampling data and the data value of the sampling data indicated by the immediately preceding arrow Q2 as the first amplitude difference. To do. Further, the amplitude difference calculation unit 603 calculates the difference between the data value of the sampling data indicated by the arrow Q1 and the data value of the sampling data indicated by the arrow Q3 immediately after that. The amplitude difference calculation unit 603 performs such processing for all the sampling data acquired by the sampling unit 602.

  Expressing this in a general form, the amplitude difference calculation unit 603 for the i-th sampling data D (i), the sampling data D (i), the previous sampling data, and D (i−1) The difference “D (i) −D (i−1)” is the first amplitude difference, and the difference “D (i + 1) −D between the sampling data D (i) and the next sampling data D (i + 1)”. (I) "is calculated as the second amplitude difference.

  The plot unit 604 sets a two-dimensional coordinate system in which the first amplitude difference is the X axis and the second amplitude difference is the Y axis, and the first amplitude calculated by the amplitude difference calculation unit 603 for each sampling data The points having the difference and the second amplitude difference as the X coordinate and the Y coordinate, respectively, are plotted in the two-dimensional coordinate system. That is, as illustrated in FIG. 7, the plot unit 604 calculates the first amplitude difference “D (i) −D (i−) for the i-th sampling data D (i) calculated by the amplitude difference calculation unit 603. 1) ”is the X coordinate Xi, and the second amplitude difference“ D (i + 1) −D (i) ”for the i-th sampling data D (i) calculated by the amplitude difference calculation unit 603 is the Y coordinate Yi. As shown in FIG. 8, the point Pi (Xi, Yi) is plotted in the two-dimensional coordinate system. An example of the distribution of plot points for all sampling data is shown in FIG.

The coordinate system conversion unit 605 converts the distribution of each plot point in the two-dimensional coordinate system obtained by the processing of the plot unit 604 into a distribution expressed in a polar coordinate system. Thereby, the position of each plot point is the distance r (= (Xi ² + Yi ² ) ^1/2 ) between the plot point and the origin in the two-dimensional coordinate system, and the plot point and the origin in the two-dimensional coordinate system. Is represented by an angle θ (= tan ⁻¹ (Yi / Xi)) with respect to the X axis of a line segment connecting the two.

  The area-specific plot number counting unit 606 divides the polar coordinate system into a plurality of areas in accordance with the angle θ, and calculates the number of plot points (number of plots) in each area. 11 divides the polar coordinate system in increments of π / 2, a divided region 1 with angles “0” to “π / 2”, a divided region 2 with angles “π / 2” to “π”, and an angle “ By setting four divided areas of divided areas 3 of π ”to“ 3π / 2 ”and divided areas 4 of angles“ 3π / 2 ”to“ 2π ”, each of the two-dimensional coordinate systems shown in FIG. The distribution when plot points are expressed in a polar coordinate system is shown.

  The area-specific plot number counting unit 606 counts the number of plot points in each of the divided areas 1 to 4 set in the polar coordinate system. FIG. 11 shows 5354 plot points in segmented area 1, 2145 plot points in segmented area 2, 5025 plot points in segmented area 3, and 1985 plot points in segmented area 4. This indicates that the area-specific plot number counting unit 606 has detected that each exists.

  In the case of an old bill, since the absolute amount of generated sound is small and relatively smooth, the first amplitude difference and the second amplitude difference for each sampling data have a small absolute amount and the first amplitude difference. And the second amplitude difference are opposite to each other. On the other hand, in the case of a new bill, since the absolute amount of generated sound is large and intense, the first amplitude difference and the second amplitude difference for each sampling data have a large absolute amount and the first amplitude difference. The positive and negative with the second amplitude difference tends to be the same.

  When the above points are combined, as shown in FIG. 12, when the polar coordinate system is divided into the four divided areas 1 to 4 as described above, the plot points for the old bill are divided into the divided areas 2 and 4. It becomes easy to be distributed near the origin, and the plot points for the new bill are likely to be distributed in the direction away from the origin of the divided areas 1 and 3.

The determination unit 608 determines the fatigue state of the banknote based on the number of plot points in each divided region 1 to 4 calculated by the region-by-region plot number counting unit 606. In the present embodiment, the reference value for the new bill and the reference value for the old bill are preset for each of the divided areas 1 to 4 for the number of plot points, and the reference value storage unit 607 stores the reference value in FIG. These reference values are stored in a table format as shown in FIG. For example, the reference value storage unit 607 stores “E ₁ ” as the reference value for the new bill for the divided region 1 and “F ₃ ” as the reference value for the old bill for the divided region 3.

The determination unit 608 calculates, for each divided region, a difference between the number of plot points in the divided region detected by the divided plot number counting unit 606 and a reference value for a new bill associated with the divided region. . For example, it is assumed that the number of plot points of the divided areas 1 to 4 detected by the area-specific plot number counting unit 606 is “D ₁ ”, “D ₂ ”, “D ₃ ”, and “D ₄ ”, respectively. The determination unit 608 calculates | D ₁ −E ₁ |, | D ₂ −E ₂ |, | D ₃ −E ₃ |, | D ₄ −E ₄ |. Then, the determination unit 608 adds these values. This addition result is referred to as addition result 1.

Similarly, the determination unit 608 determines, for each divided area, the number of plot points in the divided area detected by the area-specific plot number counting unit 606 and the reference value for the old bill associated with the divided area. Calculate the difference. For example, it is assumed that the number of plot points of the divided areas 1 to 4 detected by the area-specific plot number counting unit 606 is “D ₁ ”, “D ₂ ”, “D ₃ ”, and “D ₄ ”, respectively. The determination unit 608 calculates | D ₁ −F ₁ |, | D ₂ −F ₂ |, | D ₃ −F ₃ |, | D ₄ −F ₄ |. Then, the determination unit 608 adds these values. This addition result is referred to as addition result 2.

  The determination unit 608 compares the addition result 1 and the addition result 2 to derive an addition result having a smaller addition value, and based on the addition result, the fatigue state ( New bill / old bill). Specifically, the determination unit 608 determines that the banknote to be determined this time is a banknote in a fatigue state (new bill / old bill) corresponding to the reference value used when deriving the addition result with the smaller addition value. judge. That is, the determination unit 608 determines which reference value the number of plot points is closer to, and determines that the fatigue state corresponds to the closer reference value.

  For example, when the value indicated by the addition result 2 is smaller than the value indicated by the addition result 1, the determination unit 608 pays attention to the addition result 2 and uses the criterion used to derive the addition result 2. The value is a reference value for an old bill, and it is determined that the bill to be determined this time is an old bill. As described above, the determination unit 608 determines whether the number of plot points in each divided region detected by the region-by-region plot number counting unit 606 is approximate to the reference value for the new bill as a whole, or the old value. It is determined whether the bill is approximate to the reference value for bills, and it is determined that the bill is in a fatigue state (new bill / old bill) corresponding to the reference value that is approximated.

  Next, operation | movement of the banknote processing apparatus 1 is demonstrated below. FIG. 14 is a flowchart showing the flow of banknotes when depositing by the banknote handling apparatus 1.

  As shown in FIG. 14, when a detection signal (ON signal) indicating that a banknote has been inserted from the banknote insertion slot 20a is output from the banknote insertion sensor 502 provided in the vicinity of the banknote insertion slot 20a (step #). 1), the control unit 600 drives a motor (not shown) of the bill introduction mechanism 21 to cause the bill introduction mechanism 21 to take a bill into the apparatus 1 (step # 2). At this time, the bill is introduced at a relatively low speed by driving the motor.

  Next, the control unit 600 determines the denomination while the banknote is being conveyed (step # 3), and determines the authenticity of the banknote if the denomination can be determined (YES in step # 4). (Step # 5). When it is determined that the banknote is a true note (YES in step # 6), the control unit 600 identifies a fatigue state described later for the banknote (step # 7), and then determines the identified banknote. Depending on the denomination and fatigue state, the bill is taken into the unit that should take in the bill (step # 8).

  If the denomination cannot be identified (NO in step # 4), and if the control unit 600 determines that the banknote is a bill (NO in step # 6), the banknote is discharged. Transport toward 20b (step # 9).

  Next, the fatigue state determination process in step # 7 in FIG. 14 will be described. FIG. 15 is a flowchart showing a flow of fatigue state identification processing.

  As shown in FIG. 15, when the leading edge of the bill is detected by the bill passage sensor 503 (YES in step # 11), the sound collection control unit 601 causes the microphone 501 to start the sound collection operation, and also the sampling unit 602. Starts sampling the analog output signal output from the microphone 501 at a constant sampling period T (for example, T = 1/5000 seconds) (step # 12).

  When the trailing edge of the bill is detected by the bill passage sensor 503 (YES in step # 13), the sound collection control unit 601 stops the sound collection operation by the microphone 501, and the sampling unit 602 stops the sampling operation. The amplitude difference calculation unit 603 calculates the above-described first amplitude difference and second amplitude difference for each sampling data acquired by the sampling unit 602 (step # 14).

  Next, the plot unit 604 calculates the first and second amplitudes calculated for each sampling data in a two-dimensional coordinate system set in advance with the first amplitude difference as the X axis and the second amplitude difference as the Y axis. The points having the difference as the X coordinate and the Y coordinate are plotted (step # 15), and the coordinate system conversion unit 605 obtains the distribution of each plot point in the two-dimensional coordinate system obtained by the processing of the plot unit 604 as a polar coordinate. The distribution is converted into a system distribution (step # 16).

  Then, the area-specific plot number counting unit 606 detects (counts) the number of plot points in each divided area obtained by dividing the polar coordinate system into a plurality of angles θ (step # 17), and determines the determination unit 608. Finds the difference between the number of plots detected in step # 17 and the reference value for the new bill for each divided area, and derives a value obtained by adding them as addition result 1 (step # 18). Further, the determination unit 608 obtains a difference between the number of plots detected in step # 17 and the reference value for the old bill for each divided region, and derives a value obtained by adding them as an addition result 2 (step # 19).

  Then, the determination unit 608 compares the addition result 1 with the addition result 2, and determines whether or not the value indicated by the addition result 1 is smaller than the value indicated by the addition result 2 (step # 20). If not smaller (NO in step # 20), the banknote is determined to be an old bill and set as a collection target banknote (step # 21). The banknote set as the collection target banknote is stored in the base unit 3. If the old bills stored in the base unit 3 are distributed again in the market, there is a risk that the bill processing device 1 or a device such as a vending machine or a money changer may cause a bill jam and cause a failure. The bills are separated from other banknotes so that they are not distributed to the banknotes (not used again).

  On the other hand, when the value indicated by the addition result 1 is smaller than the value indicated by the addition result 2 (YES in step # 20), the determination unit 608 determines that the banknote is a new bill and does not collect it. A bill is set (step # 22). The banknotes set as non-collection banknotes are stored in the intermediate units 4A to 4C and the like.

  As described above, in the present embodiment, paying attention to fluctuations in amplitude in a time-series signal composed of sampling data, a difference in data value between the sampling data is used as a feature amount, and the feature amount is used as described above. Since the fatigue state of the banknote is determined by performing a relatively simple process, it is possible to accurately determine the fatigue state of the banknote while avoiding or suppressing an increase in size and cost of the apparatus.

  In addition, the present inventor conducted an experiment for verifying the identification degree with respect to the fatigue state of a predetermined number of banknotes using such a banknote processing apparatus 1. As a result, as shown in FIG. 17, the present applicant obtained a result that the identification rate of the new bill was 96.1% and the identification rate of the old bill was 91.9%. These identification rates are very high values, and the applicant has confirmed that the banknote handling apparatus according to the present case can identify the fatigue state of banknotes with a high identification rate.

  In this case, the following modifications may be employed instead of or in addition to the embodiment.

  [1] In the first embodiment, the distribution of each plot point in the two-dimensional coordinate system is converted into a distribution expressed in the polar coordinate system, and the distribution of the plot points in the divided region obtained by dividing the region of the polar coordinate system into a plurality of regions. Based on this, the fatigue state of the banknote is discriminated, but without performing the process of converting the distribution of each plot point in the two-dimensional coordinate system into the distribution represented by the polar coordinate system, You may make it discriminate | determine the fatigue state of a banknote based on distribution.

  However, it is easier to calculate the fatigue state if the fatigue state of the banknote is determined based on the distribution of the plot points on the polar coordinate system. That is, in the first embodiment, the two-dimensional coordinate system is divided into four, but this is not the case. For example, in the case where the two-dimensional coordinate system is divided into eight equal parts every 45 degrees, it is identified in which region the plot points are. In order to do this, an operation for comparing the relationship between the position (coordinates) of the plot point and the position of each straight line that divides the two-dimensional coordinate system into eight equal parts is necessary. No calculation is required, and only the angle and the distance to the origin can identify the divided area. As a result, the processing time can be shortened and the discrimination efficiency can be improved.

  [2] In the first embodiment, only whether the bill to be identified is a new bill or an old bill is identified by using the reference value for a new bill and the reference value for an old bill. However, the present invention is not limited to this mode, and the fatigue level of the banknote is set to three or more levels so that the fatigue level of the banknote to be identified can be identified, or the reference value for the new bill and the old bill For example, a plurality of reference values may be provided to identify which degree of fatigue the banknote to be identified corresponds to. In this case, a reference value is set in advance corresponding to the degree of fatigue to be set, and the determination unit 608 determines to which reference value the number of plot points for the banknote to be identified is closest, and the reference value The process which determines the fatigue degree corresponding to 1 as a fatigue degree of the banknote of identification object is assumed.

  [3] As a method for determining the fatigue state of a bill by the determination unit 608, in addition to the determination method according to the first embodiment, a determination method using SVM (support vector machine) technology can be employed.

  That is, before making a new / old discrimination on a bill to be discriminated between new and old, separately prepare a plurality of sample bills (corresponding to the boundary setting paper leaves) in the same manner as in the first embodiment. The control unit 600 divides the polar coordinate system into a plurality of regions (divided regions 1 to 4) according to the angle θ (90 ° in this case), and calculates the number of data in each divided region. Next, the determination unit 608 plots coordinates corresponding to the number of data in each of the divided regions in the determination coordinate system having the number of data in each of the divided regions as coordinate axes. The determination unit 608 performs this process for each sample banknote.

  Then, the determination unit 608 sets a plurality of coordinates selected by a predetermined method among coordinates corresponding to the number of data in each divided area obtained for each sample banknote as coordinates for deriving the boundary. The boundary having the maximum margin for each coordinate is obtained, and the region of the determination coordinate system is divided into a plurality of regions by the boundary. The determination part 608 complete | finishes the process which concerns on the said sample banknote by this.

  Subsequently, the control unit 600 calculates the number of data in each of the divided regions 1 to 4 set in advance with respect to the polar coordinate system for the banknote to be determined, and corresponds to the combination of the number of data. Find the coordinates on the coordinate system. And the determination part 608 detects to which area | region this coordinate belongs to among the several area | regions produced | generated by the said boundary, and discriminate | determines the fatigue state of the said banknote based on the detection result.

  For example, assuming that only the number of data in the divided area 1 and the number of data in the divided area 2 out of the divided areas 1 to 4 are focused on for easy understanding, as illustrated in FIG. Sets a two-dimensional coordinate system in which the number of data in the divided region 1 and the number of data in the divided region 2 are coordinate axes, as the determination coordinate system. Here, as the boundary deriving coordinates, a coordinate A indicating a combination of the number of data in the divided area 1 and the number of data in the divided area 2 for a sample banknote of a certain new bill, and a certain old bill It is assumed that the coordinate B indicating the combination of the number of data in the divided area 1 and the number of data in the divided area 2 for the sample banknote is set.

  At this time, the determination unit 608 derives a straight line L that passes through the midpoint C between the point A and the point B and is orthogonal to the line segment AB as the boundary where the margin with respect to the coordinates A and B is maximized. The region of the two-dimensional coordinate system is divided into a region G and a region H by L.

  Then, when the control unit 600 detects the number of data in each of the divided areas 1 and 2 for each banknote to be determined, the determination unit 608 calculates the number of data in the divided area 1 and the number of data in the divided area 2. It is determined whether a point on the determination coordinate system (hereinafter referred to as a detection point) corresponding to a combination belongs to the region G or the region H, and based on the result, a banknote is determined. Judgment of fatigue state.

  Even with such processing, it is possible to accurately determine the fatigue state of the banknote with relatively simple processing.

  Here, for simplification of description, attention is paid only to the divided area 1 and the divided area 2, but there are actually divided areas 3 and 4 as well. Therefore, the determination unit 608 performs the same processing as described above for each combination of the divided area 2 and the divided area 3, the divided area 3 and the divided area 4, and the divided area 4 and the divided area 1.

  In the above description, the boundary is a straight line. However, when three or more coordinates are selected as the coordinates for setting the boundary, the boundary is not necessarily a straight line, and may be a curved line or a bent line. . Furthermore, in the above description, focusing on the combination of two divided areas among the divided areas 1 to 4, the two-dimensional coordinate system is set as described above to determine the boundary in the coordinate system. Focusing on the combination of three divided areas among ˜4, and setting a three-dimensional coordinate system having the number of data in those divided areas as a coordinate axis to obtain the boundary in the coordinate system, the boundary Becomes a plane, a curved surface, a bent surface, or the like.

  [4] In the above embodiment, the polar coordinate system is divided in increments of π / 2 to generate divided regions, but the division unit of the polar coordinate system is not limited to π / 2, and π / 3, π / 4, π / 5 etc. can be suitably changed. This increment unit may be set arbitrarily. Also, if the step unit is set to π / 3 or π / 4 instead of π / 2, the distribution of plot points can be analyzed in more detail, and the features indicated by the distribution can be easily extracted.

  [5] In the above embodiment, the identification target of the fatigue state is a banknote, but the present invention is not limited to the banknote and can be applied to all paper sheets.

DESCRIPTION OF SYMBOLS 1 Banknote processing apparatus 3 Base unit 4A-4C Intermediate | middle part unit 21 Banknote introduction mechanism 210 Banknote introduction path 501 Microphone 502 Banknote insertion sensor 503 Banknote passage sensor 600 Control part 601 Sound collection control part 602 Sampling part 603 Amplitude difference calculation part 604 Plotting part 605 coordinate system conversion unit 606 area-specific plot number counting unit 607 reference value storage unit 608 determination unit

Claims (11)

A sampling unit that samples a signal corresponding to sound generated during conveyance of paper sheets as sampling data multiple times;
Data value difference between each sampling data and predetermined sampling data sampled before the sampling data, and data value difference between each sampling data and predetermined sampling data sampled after the sampling data Are respectively calculated as first and second amplitude differences;
A set of data composed of the first and second amplitude differences calculated for one sampling data is plotted in a predetermined coordinate system, and the fatigue of the paper sheets based on the distribution of the plotted data A paper sheet fatigue discrimination device including a discrimination unit for discriminating a state. The discrimination unit
In a two-dimensional coordinate system set with the first amplitude difference and the second amplitude difference as coordinate axes, a set of data composed of the first and second amplitude differences respectively calculated for each sampling data. Plot and
Converting the distribution of data plotted in the two-dimensional coordinate system into a distribution represented by a polar coordinate system as the predetermined coordinate system;
The paper sheet fatigue determination apparatus according to claim 1, wherein a fatigue state of the paper sheet is determined based on a distribution of data plotted in the polar coordinate system. The discrimination unit
The first and second amplitudes calculated for each of the sampling data in a two-dimensional coordinate system as the predetermined coordinate system set with the first amplitude difference and the second amplitude difference as coordinate axes, respectively. Plot a set of data consisting of differences,
The paper sheet fatigue determination apparatus according to claim 1, wherein a fatigue state of the paper sheet is determined based on a distribution of data plotted in the two-dimensional coordinate system. The discrimination unit
Detecting the number of data plotted in each divided area obtained by dividing the predetermined coordinate system into a plurality of areas in a predetermined form for each divided area;
The number of data detected for each divided region is compared with a plurality of reference values corresponding to the divided region among a plurality of predetermined reference values corresponding to a plurality of fatigue states for each divided region, The fatigue state corresponding to the closest reference value among the plurality of reference values to be compared is determined as the fatigue state of the paper sheet. The described paper sheet fatigue discrimination device. The discrimination unit
For a plurality of boundary setting paper sheets prepared in advance, the number of data plotted in each of the divided areas obtained by dividing the predetermined coordinate system into a plurality of areas in a predetermined form is determined for each divided area. To detect
In the determination coordinate system set with the number of data in each divided area as a coordinate axis, respectively, obtain coordinates indicating the number of data in each divided area,
A plurality of coordinates among the obtained coordinates on the determination coordinate system are set as coordinates for deriving a boundary,
After obtaining a boundary based on the coordinates for deriving the boundary and dividing the region of the determination coordinate system into a plurality of regions by the boundary,
For the paper sheets to be discriminated, the number of data plotted in each divided area obtained by dividing the predetermined coordinate system into a plurality of areas in a predetermined form is detected for each divided area,
Find the coordinates on the determination coordinate system corresponding to the number of plotted data, detect which region the coordinate belongs to among a plurality of regions divided by the boundary, The paper sheet fatigue determination apparatus according to any one of claims 1 to 3, wherein the fatigue state of the paper sheet is determined based on the detection result. The paper sheets are banknotes,
A slot for inserting bills;
A paper sheet fatigue discriminating device for discriminating the fatigue state of a bill inserted from the insertion slot;
A banknote processing apparatus comprising: a storage unit that sorts and stores the banknotes according to fatigue states based on a determination result by the paper sheet fatigue determination apparatus;
The paper sheet fatigue determination device is a paper money processing device which is the paper sheet fatigue determination device according to any one of claims 1 to 5. A sampling step in which the sampling unit samples a signal according to the sound emitted during the conveyance of the paper sheets as sampling data a plurality of times,
Difference in data value between each sampling data and predetermined sampling data sampled before the sampling data, and predetermined sampling data sampled after each sampling data and the sampling data And a calculation step for calculating a difference between the data values as first and second amplitude differences, respectively,
The discrimination unit plots a set of data composed of the first and second amplitude differences calculated for one sampling data in a predetermined coordinate system, and the paper is based on the distribution of the plotted data. A paper sheet fatigue discrimination method comprising: a discrimination step of discriminating a fatigue state of a leaf. The determination step includes
The discriminating unit is configured from the first and second amplitude differences calculated for each sampling data in a two-dimensional coordinate system set with the first amplitude difference and the second amplitude difference as coordinate axes, respectively. Plotting a set of data;
Converting the distribution of data plotted in the two-dimensional coordinate system into a distribution represented by a polar coordinate system as the predetermined coordinate system;
The paper sheet fatigue determination method according to claim 7, wherein the determination unit includes a step of determining a fatigue state of the paper sheet based on a distribution of data plotted in the polar coordinate system. The determination step includes
The determination unit sets the first amplitude difference and the second amplitude difference as coordinate axes, respectively. The two-dimensional coordinate system as the predetermined coordinate system is calculated for each of the sampling data. Plotting a set of data comprising a first and second amplitude difference;
The paper sheet fatigue determination method according to claim 7, wherein the determination unit includes a step of determining a fatigue state of the paper sheet based on a distribution of data plotted in the two-dimensional coordinate system. The determination step includes
A step of detecting, for each divided region, the number of data respectively plotted in each divided region obtained by dividing the predetermined coordinate system into a plurality of regions in a predetermined manner;
A plurality of reference values corresponding to the divided area among a plurality of reference values determined in advance by the determination unit corresponding to a plurality of fatigue states for each divided area corresponding to the number of data detected for each divided area. And determining the fatigue state corresponding to the closest reference value among the plurality of reference values to be compared as the fatigue state of the paper sheet. The paper sheet fatigue discrimination method according to any one of 7 to 9. The determination step includes
For each of a plurality of boundary setting paper sheets prepared in advance, the data plotted in each divided area obtained by dividing the predetermined coordinate system into a plurality of areas in a predetermined form Detecting a number for each divided region;
In the determination coordinate system in which the determination unit is set with the number of data in each divided region as a coordinate axis, respectively, obtaining coordinates indicating the number of data in each divided region;
The step of setting a plurality of coordinates among the determined coordinates on the determination coordinate system as coordinates for deriving a boundary;
The determination unit obtains a boundary based on the boundary derivation coordinates, and divides the region of the determination coordinate system into a plurality of regions by the boundary; and
The discriminating unit then divides the number of data plotted in each divided area obtained by dividing the predetermined coordinate system into a plurality of areas in a predetermined form for the paper sheet to be discriminated. Detecting for each region;
The determination unit obtains coordinates on the determination coordinate system corresponding to the number of plotted data, and the coordinates belong to any of a plurality of regions divided by the boundary. And detecting the fatigue state of the paper sheet based on the detection result. 10. The paper sheet fatigue determination method according to claim 7, further comprising:

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