JP2012093874A - Bill identification device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bill identification device that is improved in acceptance rate by preventing a decrease in identification accuracy due to a slide or tilt of a bill.SOLUTION: A bill identification device 1 includes: a two-dimensional movement quantity detection sensor 50 which detects movement quantity data on a bill conveyor belt 44 from reflected light having irradiated a marker 100 on the bill conveyor belt 44, and detects movement quantity data on the bill from reflected light having irradiated the bill; a calibration processing unit 111A which calculates a reference movement quantity per unit output of the two-dimensional movement quantity sensor 50 based upon the movement quantity data on the bill conveyor belt 44, and acquires a measurement position where feature data on the bill is read based upon the calculated reference movement quantity; a bill identification sensor 71 which detects feature data at the measurement position from the bill; a memory 120 which stores the feature data at a predetermined position on the bill as reference data; and an identification unit 112 which compares the feature data at the measurement position with the reference data stored in the memory 120 to identify whether the bill is genuine.

Description

  The present invention relates to a bill validator.

  Conventionally, bill recognition devices are mounted on vending machines and money changers. The bill recognition device transports a bill inserted from a bill insertion slot by a transport belt or a transport roller and takes it into the device, and the authenticity of the bill is detected by an identification sensor such as an optical sensor or a magnetic sensor provided in the bill transport path. It identifies the type of false.

  A pulse encoder is attached to the shaft of the drive motor that drives the conveyance belt or conveyance roller of the banknote identification device, and the characteristic data of the banknote is detected by the identification sensor in synchronization with the pulse output from the pulse encoder. Is compared with the feature data stored in the memory to identify the authenticity and type of the banknote and to count the number of pulses of the pulse encoder until the banknote passes the position of a specific sensor. Judgment is made.

  In the memory of the banknote identification device, reference data (extracted from the characteristic data of the genuine banknote) used for comparison with the characteristic data detected by the identification sensor is stored in advance. When it is determined by the above identification that the bill inserted into the insertion slot is not a genuine note, an operation of rotating the drive motor in the reverse direction and returning the bill is performed.

  In such a banknote identification device, the contamination of parts such as a conveyor belt, a conveyor roller, etc., or wet banknotes, broken banknotes, and shabby banknotes without scrapes are inserted. In some cases, the banknotes being conveyed are inclined (skew) or slipped.

  When skew or slip occurs during the conveyance of banknotes, the banknotes are clogged, and even if a return operation is performed, the banknotes cannot be returned and the banknote identification device cannot be used. In addition, since the identification process is performed in synchronization with the pulse of the pulse encoder, if a slip occurs, the detection position (identification point) by the identification sensor is shifted, and an identification failure occurs.

  In Patent Document 1, in order to solve these problems, in a banknote identification device mounted on a vending machine or the like, slipping of banknotes is performed by a pulse encoder attached to a pressing roller and a pulse encoder attached to a motor shaft. A technique for performing identification corresponding to the above is disclosed. In other words, if there is a difference in the width of the pulse signals generated from both pulse encoders, it is determined that bill slipping has occurred, and the feature data of the bills is synchronized with the output signal of the pulse encoder on the pressing roller side. Detected.

  Patent Document 2 describes a technique in which a signal output in chronological order from an identification sensor is normalized by a bill conveyance distance and determined.

  On the other hand, in Patent Document 3 and Patent Document 4, in a paper sheet transport apparatus such as a copying machine, a two-dimensional movement amount detection sensor similar to that used in an optical mouse sensor or the like is used. A technique for detecting skew and slip in real time is disclosed.

JP 2000-348233 A JP-A-10-255098 JP 2005-41623 A JP 2005-206307 A

  However, as shown in Patent Document 1, even if the detection of the feature data by the identification sensor is synchronized with the output signal of the pulse encoder on the pressing roller side, if the slip of the banknote occurs on the pressing roller side, the deviation of the identification point Occurrence cannot be prevented, and the identification accuracy deteriorates.

  In the technique disclosed in Patent Document 2, since the output of the identification sensor is normalized by the conveyance distance of banknotes, when partial banknote slip occurs, all the identification points are shifted, and the identification accuracy is increased. There is a limit to improvement.

  On the other hand, in the technologies disclosed in Patent Document 2 and Patent Document 3, there is an error (variation) in the two-dimensional movement amount detection sensor itself, and thus it has not been possible to accurately detect skew or slip of paper sheets. .

  Here, the error of the two-dimensional movement amount detection sensor includes a drive angle error and a distance measurement error. The error in the driving angle of the two-dimensional movement amount detection sensor is an error in the driving angle of the measurement object with respect to a CCD (Charge Coupled Device Image Sensor) provided in the two-dimensional movement amount detection sensor. The error in the drive angle is caused by an assembly error of the two-dimensional movement amount detection sensor and the paper sheet transport device.

  In addition, the distance measurement error of the two-dimensional movement detection sensor is subject to the principle of the two-dimensional movement detection sensor that reads the optical image from the lens with a CCD and detects the movement distance in two directions with a DSP (Digital Signal Processor). The size of the optical image changes depending on the positional relationship between the object, lens, and CCD, and the distance per dot differs. An error in distance measurement is also caused by an assembly error of the two-dimensional movement amount detection sensor and the paper sheet transport device.

  By the way, from the above-described technique, by using a two-dimensional movement amount detection sensor in a bill recognition device mounted on a vending machine or the like, it is possible to detect a skew or slip during bill conveyance, and thereby It is considered that it is possible to accurately distinguish between authenticity and type.

  However, in the banknote identification device mounted in a vending machine or the like, a DC motor is used as a banknote transport drive source, and the banknote transport speed is not controlled. Moreover, since the banknote identification device mounted on the vending machine is a device having a wide range of environmental temperature to be used, which is −10 to 60 ° C. compared with general office equipment, the transport speed is around the device. It varies greatly depending on the temperature. Furthermore, the conveyance speed of a banknote changes for every apparatus by the individual difference of a banknote identification apparatus.

  Therefore, even if the individual difference (error) of the two-dimensional movement amount detection sensor as described above is corrected at the time of shipment, the conveyance speed for each banknote recognition apparatus is different, or the banknotes of the banknote identification apparatus after shipment are conveyed. Since the speed differs from the speed at the time of shipment depending on the temperature or the like, even if the output of the two-dimensional movement amount detection sensor corrected for individual differences at the time of shipment is compared with the output of the two-dimensional movement amount detection sensor during actual operation There has been a problem that skew and slip cannot be detected with high accuracy.

  For example, even if the individual difference of the two-dimensional movement amount detection sensor is corrected on the assumption that it is used in an environment of room temperature 25 ° C. at the time of shipment, the bill conveyance speed will be slow in a low temperature environment. It is erroneously determined that slipping has occurred. Further, in addition to the temperature, the conveyance speed of the banknotes is lower than that at the time of shipment due to wear of the conveyance rollers and the conveyance belt, and erroneously determined.

  An object of this invention is to provide the banknote identification device which prevented the fall of the identification accuracy by the slip and inclination of a banknote, and improved the acceptance rate in view of such a situation.

In order to solve the above-mentioned problem, the present invention is a bill identifying device for identifying the authenticity of a bill,
While detecting the movement amount data of the said conveyance means from the conveyance means which conveys the banknote inserted from the insertion port, the measurement parameter | index provided in the said conveyance device, and the reflected light which irradiated the measurement parameter | index on the said conveyance device, Movement amount detection means for detecting movement amount data of the banknote from reflected light irradiated on the banknote when the conveyance means is conveying the banknote, and movement amount data of the conveyance means detected by the movement amount detection means Based on the reference movement amount calculation means for calculating a reference movement amount per unit output of the movement amount detection means, and based on the reference movement amount calculated by the reference movement amount calculation means, the feature data on the banknote is obtained. Measurement position acquisition means for acquiring a measurement position to be read; feature data detection means for detecting feature data at the measurement position from the banknote; and feature data at a predetermined position on the banknote. Reference data storage means for storing data as reference data, and identification means for comparing the feature data at the measurement position with the reference data stored in the reference data storage means for identifying the authenticity of the bill. .

  In the above invention, the measurement index is preferably a plurality of indexes provided at a predetermined interval on the banknote transport belt or banknote transport roller.

  In the above invention, the movement amount detection means detects movement amount data of the measurement index until a bill inserted from the insertion slot reaches a detection position of the movement amount detection means.

  According to the present invention, the feature data is detected by the banknote identification sensor in synchronization with the output of the two-dimensional movement amount detection sensor. Decrease can be prevented, which helps improve the acceptance rate.

It is principal part sectional drawing of the banknote identification device which concerns on this invention. It is a figure which shows the structure of a two-dimensional movement amount detection sensor. It is a schematic side view which shows the mechanism of a banknote identification device. FIG. 4 is a top view of FIG. 3. It is a block diagram which shows the control function of a banknote identification device. It is a figure explaining the data reading timing of a banknote identification sensor. It is a flowchart explaining operation | movement of a banknote identification device. It is a figure explaining the data processing method at the time of skew generation. It is a figure which shows the modification of FIG. It is a figure which shows the modification of FIG. FIG. 10 is a side view of FIG. 9. It is a figure which shows the modification of FIG.

<Outline of configuration of bill validator>
First, a schematic configuration of the banknote recognition apparatus according to the present invention will be described with reference to FIG.
FIG. 1 is a cross-sectional view of an essential part of a bill identifying device according to the present invention.

  As shown in FIG. 1, this banknote identification apparatus 1 is mounted in, for example, a vending machine, and is provided in an apparatus main body 3 that is a housing having a banknote insertion slot 2, and in the apparatus main body 3. A banknote transport means 4 for transporting a banknote inserted into the insertion slot 2 along a banknote transport path in the apparatus main body 3, and a banknote identification means 5 for identifying the authenticity and denomination of the banknote transported by the banknote transport means 4. And a stacker 6 that accommodates banknotes identified as genuine bills by the banknote identifying means 5.

  The apparatus main body 3 includes a front mask 7 in which a bill insertion slot 2 is formed and disposed so as to be exposed from a part of a door constituting the front of a vending machine (not shown), and a front mounted with the front mask 7 on the front. It comprises a plate 8 and a rectangular housing 9 fixed to the front plate 8. The banknote insertion slot 2 is provided with an inlet sensor 21 that detects insertion of banknotes. The entrance sensor 21 is a reflection type optical sensor, but may be a transmission type optical sensor or a sensor that directly receives a bill and detects acceptance.

  The bill conveying means 4 and the bill identifying means 5 are provided in the unit box 11. The stacker 6 is supported below the housing 9 via bearing means 12 so as to be rotatable and detachable.

  The banknote transport means 4 includes a motor 41 provided in the upper part of the unit box 11, a drive pulley 42 that transmits the rotation of the motor 41 to an endless banknote transport belt 44, and the drive pulley 42. Are driven pulleys 43, and driven rollers 45 </ b> A to 45 </ b> D provided at predetermined intervals on the peripheral surface of the banknote transport belt 44.

  A gear train (not shown) is provided between the shaft 42a for supporting the drive pulley 42 and the drive shaft 41a of the motor 41, and the gear train functions as power transmission means. When the motor 41 is driven based on a drive signal from a control unit (not shown) and the drive shaft 41a rotates in one direction, the shaft 42a of the drive pulley 42 rotates in one direction via the gear train, and the banknote transport belt. 44 rotates in one direction.

  The driven rollers 45 </ b> A to 45 </ b> D are provided so as to be in pressure contact with the surface of the banknote transport belt 44. The inserted banknote is conveyed in the rotation direction of the banknote transport belt 44 while being sandwiched between the banknote transport belt 44 by the driven rollers 45A to 45D as the banknote transport belt 44 rotates.

  The bill identifying means 5 is composed of a plurality of light emitting elements 51 and a plurality of light receiving elements 52 that detect the density of a specific position of a passing bill as feature data. The plurality of light emitting elements 51 are mounted on a printed wiring board 54 accommodated in the unit box 11, and the plurality of light receiving elements 52 are mounted on a printed wiring board 55.

  A two-dimensional movement amount detection sensor 50 is provided at a position facing the banknote transport belt 44 across the banknote transport path. The two-dimensional movement amount detection sensor 50 is a sensor having the same function as a two-dimensional movement amount detection sensor mounted on an optical mouse used as a user interface of a personal computer or the like, and is a movement amount of an object to be measured. And a sensor that outputs information on the amount of movement in the X direction and the Y direction as information indicating the direction of movement and the amount of received light.

  FIG. 2 is a diagram illustrating a configuration of the two-dimensional movement amount detection sensor 50. The two-dimensional movement amount detection sensor 50 includes a light source 81, a two-dimensional light receiving element array 83, and a lens 82 for focusing the light irradiated from the light source 81 and reflected on the object to be measured on the two-dimensional light receiving element array 83. . The two-dimensional light receiving element array 83 is made of a complementary metal oxide semiconductor (CMOS). The two-dimensional light receiving element array 83 can also use another imaging device such as a charge coupled device (CCD).

  Based on the output from the two-dimensional light receiving element array 83, the arithmetic processing unit 85 calculates the amount of movement of the object in the X direction and the Y direction, and represents the amount of movement in the X direction and Y direction obtained by the calculation. And information indicating the amount of received light is output to the outside via the interface 86. Since the principle of detection of the movement amount by the two-dimensional movement amount detection sensor 50 is a known technique as described in Japanese Patent Application Laid-Open No. 2005-41623 and the like, detailed description thereof is omitted.

  The banknote handling apparatus 1 is equipped with such a two-dimensional movement amount detection sensor 50, so that each banknote transport belt 44 and each banknote transported (the X-direction movement amount and the Y-direction movement amount) are transferred. The amount of received light reflected from each of the banknote transport belt 44 and the banknotes to be transported can be acquired, and the tilt and slip of the banknotes being transported can be detected.

  The two-dimensional movement amount detection sensor 50 is disposed in the vicinity of the banknote transport belt 44 that is hung on the driven pulley 43. When the two-dimensional movement amount detection sensor 50 is arranged at a position close to the driven pulley 44 and the drive pulley 42 as described above, the distance between the two-dimensional movement amount detection sensor 50 and the banknote transport belt 44 is relatively constant. The amount of movement of the bills and bill transport belt 44 (the amount of movement in the X direction and the amount of movement in the Y direction) can be detected with high accuracy.

<Configuration of banknote transport mechanism>
Next, the banknote conveyance means 4, the banknote identification means 5, and the two-dimensional movement amount detection sensor 50 mounted on the banknote recognition apparatus 1 of this embodiment will be described in detail with reference to FIGS.
FIG. 3 is a schematic side view showing the mechanism of the banknote conveying means 4, and FIG. 4 is a top view of FIG. Of the configurations shown in FIGS. 3 and 4, the same reference numerals are given to the same configurations as the configurations shown in FIG. 1, and overlapping descriptions are omitted as appropriate.

  The banknote inserted into the banknote insertion slot 2 as shown by the white arrow # 1 in FIG. 3 is detected by the inlet sensor 21, and is driven by the banknote transport belt 44 driven by the motor 41 through the drive pulley 42. It is transported into the device.

  The bills conveyed to the inside of the apparatus pass through the positions of the driven roller 45A and the driven roller 45B, and the detection position of the two-dimensional movement amount detection sensor 50 indicated by the tip of the white arrow # 2 (two-dimensional movement amount detection sensor 50 To the position). Further, it passes through the position of the driven roller 45 </ b> C and passes through the position where the bill identification sensor 71 including the light emitting element 51 and the light receiving element 52 is provided. When the banknote passes the banknote identification sensor 71, the banknote processing apparatus 1 determines the authenticity of the banknote based on the output of the banknote identification sensor 71. If it is determined that the bill is authentic, the bill passes through the position of the driven roller 45D and is accommodated in the stacker 6.

As shown in FIG. 4, the bill identification device 1 is provided with two of the same configurations as the drive pulley 42, the driven pulley 43, and the bill transport belt 44 shown in FIG. 3 in parallel. A plurality of banknote identification sensors 71 are provided side by side in a direction orthogonal to the transport direction.
The upper drive pulley 42 and the lower drive pulley 42 are connected by a shaft 42a, and the motor 41 is connected to the shaft 42a via a gear train or the like serving as power transmission means. The upper driven pulley 43 and the lower driven pulley are connected by a shaft (not shown).
The two-dimensional movement amount detection sensor 50 is provided in the vicinity thereof to detect the movement amount of the lower banknote transport belt 44, and a marker as a measurement index is provided on the banknote contact surface of the lower banknote transport belt 44. A plurality of 100 are provided at predetermined intervals. The marker 100 on the bill conveyance belt 44 is irradiated by the two-dimensional movement amount detection sensor 50 until the bill conveyed by the bill conveyance belt 44 reaches the detection position of the two-dimensional movement amount detection sensor 50. The movement amount data of the banknote transport belt 44 is detected from the reflected light.
In the embodiment, the conveyor belt 44 is black and the marker 100 is white. The banknote recognition apparatus 1 detects the marker 100 on the conveyance belt 44 based on the change in the amount of received light acquired by the two-dimensional movement amount detection sensor 50.

  Next, the functional configuration of the control unit (CPU 101) of the banknote recognition apparatus 1 will be described in detail. FIG. 5 is a block diagram illustrating a functional configuration of the control unit 101.

As shown in FIG. 5, the CPU 101 functioning as a control unit executes a predetermined program stored in advance in the memory 120, thereby realizing a mouse sensor control unit 111, an identification unit 112, and a motor control unit 113. .
The two-dimensional movement amount detection sensor 50 is inserted from the banknote insertion slot 2, and until the banknote conveyed by the banknote conveyance belt 44 reaches the detection position of the two-dimensional movement amount detection sensor 50, the banknote conveyance belt 44. The movement amount data of the banknote transport belt 44 is detected from the reflected light irradiated on the upper marker 100. The two-dimensional movement amount detection sensor 50 detects the movement amount data of the banknote after the banknote passes the detection position of the two-dimensional movement amount detection sensor 50.

The mouse sensor control unit 111 discriminates slipping and inclination of the banknote based on information acquired by the two-dimensional movement amount detection sensor 50. The identification unit 112 discriminates the authenticity and denomination of the banknote based on the output signal from the banknote identification sensor 71 and the information from the mouse sensor control unit 111. The motor control unit 113 controls conveyance of bills in the receiving direction, conveyance in the return direction, and stopping. The memory 120 stores feature data at a predetermined position on the bill as reference data.
The mouse sensor control unit 111 includes a calibration processing unit 111A, a skew detection unit 111B, and a slip detection unit 111C. The identification unit 112 includes an identification address correction processing unit 112A and an identification processing unit 112B.

  Each time the calibration processing unit 111A detects that a banknote has been inserted based on the output signal of the entrance sensor 21, the calibration processing unit 111A is based on the movement amounts in the X direction and the Y direction acquired by the two-dimensional movement amount detection sensor 50. Thus, reference data representing the amount of movement and the direction of movement of the banknote transport belt 44 in a state in which there is no banknote (in other words, a state in which the banknote that has not yet been transported to the two-dimensional movement amount detection sensor 61) is obtained. Remember. Further, the calibration processing unit 11A obtains a reference received light amount based on the received light amount acquired by the two-dimensional movement amount detection sensor 50, and stores the reference data and the reference received light amount in the memory 120. The calibration processing unit 111 </ b> A detects that the inserted banknote has reached the position of the two-dimensional movement amount detection sensor 50 based on a change in the amount of received light. When the calibration processing unit 111 </ b> A detects that the banknote has reached the position of the two-dimensional movement amount detection sensor 50 based on the change in the amount of received light, the calibration processing unit 111 </ b> A obtains conveyance state information indicating the movement amount and movement direction of the banknote.

  The calibration processing unit 111A calculates the reference movement amount per unit output of the two-dimensional movement amount detection sensor 50 based on the movement amount data of the bill conveyance belt 44 detected by the two-dimensional movement amount detection sensor 50. Furthermore, the calibration processing unit 111A acquires a measurement position for reading the feature data on the banknote based on the calculated reference movement amount.

The skew detection unit 111B detects the skew of the banknote by comparing the movement direction of the banknote obtained by the calibration processing unit 111A as the conveyance state information with information indicating the movement direction of the reference data stored in the memory 120.
The slip detection unit 111 </ b> C detects the slip of the banknote by comparing the movement amount of the banknote obtained as the conveyance state information obtained by the calibration processing unit 111 </ b> A with the movement amount of the reference data stored in the memory 120.
Information on the skew detected by the skew detection unit 111B and information on the skew detected by the slip detection unit 111C are supplied to the identification unit 112 and the motor control unit 113.

  The identification address correction processing unit 112A corrects the identification address of the banknote transported by the banknote transport belt 44 based on the skew obtained by the skew detection unit 111B.

The identification processing unit 112B has the feature data at the measurement position acquired by the calibration processing unit 111A and the reference data of each position of the banknote stored in advance in the memory 120 and given in advance to the identification processing unit 112. And authenticate the bill.
Further, the identification processing unit 112B matches the characteristic data of the banknote after the identification address correction detected by the banknote identification sensor 71, and identifies the authenticity and type of the banknote. Information indicating the authenticity of the banknote identified by the identification processing unit 112B is output to the motor control unit 113.

  The motor control unit 113 starts driving the motor 41 when the insertion of the banknote is detected by the entrance sensor 21. Further, the motor control unit 113 controls the motor 41 when the skew detected by the skew detection unit 111B or the slip detected by the slip detection unit 111C is so large that the identification address correction processing unit 112A cannot correct the identification address. The bill is returned by rotating it in the reverse direction. The motor control unit 113 causes the banknotes to be returned in the same manner even when the identification processing unit 112B recognizes that the inserted banknote is not a genuine note.

(Acquisition of reference data for the transport state before banknote transport)
In a predetermined period (time T1) from when the insertion of the banknote is detected until the banknote reaches the position of the two-dimensional movement amount detection sensor 50, the X direction output by the two-dimensional movement amount detection sensor 50 (banknote transport direction). If the amount of movement is X1 and the amount of movement in the Y direction (direction perpendicular to the banknote conveyance direction) is Y1, the direction reference value α1, which is a value representing the direction reference in the reference data, is expressed by the following equation (1). Desired.
α1 = ArcTan (Y1 / X1) (1)

Further, the movement amount reference value V1 of the reference data in a predetermined period (time T1) from when the insertion of the banknote is detected until the banknote reaches the detection position of the two-dimensional movement amount detection sensor 50 is obtained by the following equation (2). It is done. Since the absolute value calibration is not performed, the movement amount reference value V1 is a relative value.
V1 = SQRT (X12 + Y12) / T1 (2)

(How to obtain the transport status information after the banknote arrives and banknote skew and slip detection)
When the banknote arrives at the position of the two-dimensional movement amount detection sensor 50, the banknote is processed in the same manner as the above-described method for obtaining the reference data based on the movement amounts in the X direction and Y direction output from the two-dimensional movement amount detection sensor 50. The moving direction information α1bill is obtained from the following equation (3).
α1bill ＝ ArcTan (Ybill / Xbill) (3)

Further, based on the movement amounts in the X direction and the Y direction output from the two-dimensional movement amount detection sensor 50, V2 which is a value indicating the movement amount of the banknote is calculated by the same method as that for obtaining the reference data described above. Calculated from (4).
V2 = SQRT (Xbill2 + Ybill2) / T2 (4)

The skew and slip of the bill are obtained from the following formula.
Skew = αbill-α1 (5)

The slip of the banknote is obtained from the following formula.
Slip = V2-V1 (6)

(Method of calculating the bill movement amount per unit output of the two-dimensional movement amount detection sensor 50)
When the entrance sensor 21 detects a bill, the calibration processing unit 111A drives the motor 41 to convey the belt 44 per dot (unit output) output from the two-dimensional movement amount detection sensor 50 in a state where there is no bill. The reference movement amount is obtained.
The interval between the markers 100 attached to the transport belt 44 is L0, and the number of dots output from the two-dimensional movement amount detection sensor 50 in the banknote transport direction (X direction) without banknotes per L0 is X0 (dots). The reference movement amount X2 (mm) per dot (unit output) in the case of being found is obtained from the following equation (7).
X2 = L0 / X0 (7)

(Sampling method using the output of the two-dimensional movement detection sensor 50)
The number of dots X3 output from the two-dimensional movement amount detection sensor 50 necessary for conveying a bill at a predetermined sampling interval L1 (mm) is obtained from Expression (8).
X3 = L1 / X2 (8)
Here, the number of dots X3 is a measurement position for reading feature data on a bill.
For example, when the interval L0 of the marker 100 on the conveyor belt 44 is 10 mm, and sampling is performed every 0.5 mm, the two-dimensional movement detection sensor between the markers output from the two-dimensional movement detection sensor 50 is used. When the number of 50 dots is 1000 dots,
When L0 = 10 mm, L1 = 0.5 mm, and X0 = 1000 dots,
・ Reference movement amount per unit output: X2 = 10/1000 = 0.01 mm / dot ・ Measurement position: X3 = 0.5 / 0.01 = 50 dots Therefore, in order to perform sampling every 0.5 mm, it is necessary to perform sampling every movement amount (measurement position) X3 = 50 dots of the two-dimensional movement amount detection sensor 50.

  Next, a method for sampling bill feature data will be described. FIG. 6 is a diagram illustrating a method for sampling feature data of banknotes, (a) is a diagram for explaining an identification point as a banknote sampling position, and (b) is a conventional example in which sampling is performed in synchronization with the output of a pulse encoder. FIG. 4C is a diagram for explaining the shift of the sampling position when the bill is slipped in the bill processing apparatus for sampling in synchronization with the output of the pulse encoder, and FIG. It is a figure which shows the method of sampling in synchronization with the output of the detection sensor. The output waveform and sampling timing of the banknote identification sensor 71 are shown in FIGS.

As shown in FIG. 6A, the banknote B has a large number of identification pointers A arranged at equal intervals. This identification point A is a sampling point of the banknote identification sensor 71. Conventionally, the output signal of the banknote identification sensor 71 is sampled in synchronization with the output signal of the pulse encoder attached to the motor 41 as shown in FIG.
However, as shown in FIG. 3C, when the bill slips, the sampling position of the bill recognition sensor 71 is moved away from the identification point A, and there is an error between the reference data on the identification point A and the actual measurement data. There was a problem that would cause.

  Therefore, in the present embodiment, as shown in FIG. 4D, by sampling the output signal of the banknote identification sensor 71 in synchronization with the output of the two-dimensional movement amount detection sensor 50, even if the banknote slips, The bill identification sensor 71 can accurately sample the feature data on the identification pointer A. Accordingly, it is possible to prevent a decrease in identification accuracy due to the slipping of banknotes and improve the acceptance rate.

Next, operation | movement of the banknote identification device 1 is demonstrated. FIG. 7 is a flowchart for explaining the operation of the banknote recognition apparatus.
As shown in FIG. 7, when insertion of a banknote is detected by the entrance sensor 21 in step S1 (Yes in step S1), in step S2, the motor control unit 113 controls the motor 41 to control the inserted banknote. Start conveyance.

In step S <b> 3, the calibration processing unit 111 </ b> A determines whether or not the bill is transferred based on the movement amount of the bill conveyance belt 44 detected by the two-dimensional movement amount detection sensor 50 before the bill reaches the position of the two-dimensional movement amount detection sensor 50. Reference data is obtained by equations (1) and (2).
Further, the calibration processing unit 111A acquires a reference received light amount.

  In addition, the calibration processing unit 111A uses the movement amount data of the banknote transport belt 44 detected by the two-dimensional movement amount detection sensor 50 to calculate the reference movement per unit output of the two-dimensional movement amount detection sensor 50 using Expression (7). Calculate the amount. Furthermore, the calibration processing unit 111A acquires a measurement position for reading the feature data on the banknote using Expression (8) based on the calculated reference movement amount.

In step S <b> 4, the calibration processing unit 111 </ b> A determines whether the banknote has reached the detection position of the two-dimensional movement amount detection sensor 50 based on the change in the amount of received light detected by the two-dimensional movement amount detection sensor 50. . When it is determined in step S4 that the bill has reached the detection position of the two-dimensional movement amount detection sensor 50 (Yes in step S4), in step S5, the calibration processing unit 111A uses the above equations (3) and (4). The processing for calculating the bill conveyance state information in real time is started.
When the banknote reaches the banknote identification sensor 71, the banknote characteristic data is sampled at each measurement position X3 obtained by the above equation (8).

In step S <b> 6, the skew detection unit 111 </ b> B compares the bill conveyance state information acquired in step S <b> 5 with reference data to determine whether skew has been detected.
For example, the value obtained by the above equation (5) is compared with a predetermined threshold value, and if it exceeds the threshold value, it is determined that the skew is detected (Yes in step S6).

  If no skew is detected in step S6 (No in step S6), in step S7, the slip detection unit 111C determines whether or not slip has been detected. For example, when the value obtained by the above equation (6) is compared with a threshold value and exceeds a predetermined threshold value, it is determined that slip has been detected.

  If no slip is detected in step S7 (No in step S7), whether or not sampling by the banknote identification sensor 71 is completed in step S8, that is, whether or not the identification area of the banknote identification sensor 71 has been passed. Determine. Whether or not the bill has passed through the bill recognition sensor 71 is determined based on a change in the amount of light received by the light receiving element 52 that constitutes the bill recognition sensor 71. Here, when it is determined in step S8 that the sampling by the banknote identification sensor 71 is completed, the process returns to step S5 and the same processing is repeated.

  On the other hand, if a skew is detected in step S6 (Yes in step S6), or if slip is detected in step S7 (Yes in step S7), the identification address correction processing unit 112A performs correction in step S9. Determine whether it is possible.

  If it is determined in step S9 that the correction is possible because the skew or slip is minute (Yes in step S9), the identification address correction processing unit 112A detects the banknote detected by the skew detection unit 111B in step S10. The identification address is corrected according to the skew amount.

  On the other hand, when it is determined in step S9 that correction is impossible (No in step S9), in step S11, the motor control unit 113 controls the motor 41 to stop the conveyance of banknotes, and the motor 41 is further turned off. Reverse rotation is performed to return bills. When the bill is returned in step S10, the process is terminated.

In step S8, when it is determined that the sampling by the banknote identification sensor 71 is completed (Yes in step S8), the identification process is performed in step S12, and when the acquisition of the feature data of all banknotes is completed, the identification processing unit 112B. Compares the characteristic data at the measurement position acquired by the calibration processing unit 111A and the reference data of each position of the banknote stored in advance in the memory 120 and given to the identification processing unit 112 in advance. To identify the authenticity of the bill.
Thus, since the output signal of the banknote identification sensor 71 is sampled in synchronism with the output of the two-dimensional movement amount detection sensor 50, the banknote identification sensor 71 is characterized on the identification point A even if the banknote slips. Data can be sampled accurately. Accordingly, it is possible to prevent a decrease in identification accuracy due to the slipping of banknotes and improve the acceptance rate.

Next, the correction method for the identification address in step S10 will be described.
8A and 8B are diagrams for explaining a data processing method when a skew occurs, FIG. 8A is a diagram for explaining identification lines −1 to +1 of the banknote and the banknote identification sensor 71, and FIG. 8B is an output waveform of the banknote identification sensor 71. The figure explaining sampling timing, (c) is a figure explaining the relationship between a skew amount and a threshold value.
Here, the case of three identification lines -1 to +1 is taken as an example, and these three identification lines correspond to the number of banknote identification sensors 71 in FIG.

The identification unit 112A corrects the identification address based on the skew information from the skew detection unit 111B. Specifically, when skew occurs, the correction address is set so that the determination threshold (threshold used for determining the authenticity and type of banknotes) is widened in consideration of the variation of feature data for the portion where the skew exceeds the specified value. Perform the correction.
In addition, another identification line ± 1 is set in advance on both sides of the reference identification line 0 in the center in the width direction of the banknote B (see FIG. 8A), and the banknote identification sensor 71 is set along each identification line. The output is scanned and stored in the memory 120. (See (b) of the figure).
Then, as shown in FIG. 5C, the determination pattern is selected according to the skew amount and identification is performed. Specifically, black circle data is determined based on the reference data of the reference identification line 0, black triangle mark data is determined based on the reference data of the identification line +1, and black inverted triangle mark data is determined based on the identification line −. The determination is based on the reference data of 1.
In any method, since the determination threshold value changes according to the skew amount, it is possible to prevent a decrease in identification accuracy due to the occurrence of skew, which is useful for improving the acceptance rate.

  Next, a modification of the embodiment of the present invention will be described. FIG. 9 is a diagram showing a modification of the embodiment of the present invention. In the present embodiment, the marker 100 is provided on the banknote transport belt 44. However, as shown in FIG. 9, the rim of the driven pulley 43 is enlarged to form the measuring roller 121, and the marker is formed on the circumferential surface of the measuring roller 121. 100 may be provided. The diameter of the measuring roller 121 is the same as the diameter of the banknote transport belt 44 hung on the driven pulley 43, and the peripheral speed of the measuring roller 121 is equal to the moving speed of the banknote transport belt 44. The two-dimensional movement amount detection sensor 50 is provided at a position facing the measurement roller 121 across the conveyance path. Thereby, the amount of movement of the measuring roller 121 can be measured with higher accuracy without being affected by the fluctuation caused by the tension of the banknote transport belt 44 or the wear of the banknote transport belt 44.

Next, a modified example of the bill transport mechanism will be described.
FIG. 10 is a top view schematically showing the bill transport mechanism, and FIG. 11 is a side view of FIG. Although the said embodiment demonstrated what conveyed a banknote with the banknote conveyance belt 44, there exists what transports a banknote with a banknote conveyance roller in a banknote conveyance mechanism.
The banknote transport machine 60 includes three sets of banknote transport bodies 63 provided with banknote transport rollers 62 at both ends of a shaft 61, and these banknote transport bodies 63 are rotated in the same direction by a motor 64. A pressure roller 65 is in pressure contact with each banknote transport roller 62, and the banknote B is bitten and transported by these rollers 62 and 65.

  When the banknote B is inserted from the direction indicated by the arrow # 1 in FIG. 11, the entrance sensor 21 detects the insertion of the banknote B, and each banknote transport roller 62 is rotated by driving the motor 41. The bill B is caught in the bill transport roller 62 and the pressure roller 65 and taken into the apparatus, and passes through the detection area of the two-dimensional movement amount detection sensor 50 when the direction is reversed by the bill transport roller 62 on the left side in the drawing. . The banknote B whose direction is reversed by the banknote transport roller 62 passes through the detection area of the banknote identification sensor 71 including the light emitting element 51 and the light receiving element 52 and is bitten by the banknote transport roller 62 and the pressing roller 65 on the right side in the drawing. Discharged outside the device. In such a banknote transport machine 60, the marker 100 is provided on the peripheral surface of the banknote transport roller 62 in the detection area of the two-dimensional movement amount detection sensor 50.

FIG. 12 shows a modification of FIG.
Although the structure itself of the transport mechanism 60 is the same as that described above, a measurement roller 66 is provided inside the banknote transport roller 62 that constitutes the banknote transport body 63 on the left side in the figure, and the measurement roller 66 is moved in two dimensions. It is arranged in the detection area of the detection sensor 50. The measuring roller 66 has the same diameter as that of the banknote transport roller 62 and is provided with a marker 100 on the peripheral surface thereof. In this transport mechanism 60, since the measuring roller 66 is not pressed against the pressing roller 65, there is no risk of deterioration of measurement accuracy due to wear.

  In the above description, the case where the two-dimensional movement amount detection sensor 50 is provided on the bill conveyance belt 44 or the rim of the driven pulley 43 has been described. However, it is provided at another position such as a position on the drive shaft for driving the drive pulley. It is also possible to do so.

  In the above description, the reference data is acquired based on an example in which the insertion of the banknote is detected every time the insertion of the banknote is detected. However, in the state where the banknote is not inserted (standby state), the reference data is obtained every few minutes. It is also possible to adopt a configuration in which data acquisition is performed periodically and only the acquisition of banknote conveyance state information is executed after the banknote is inserted.

  In addition, since all the banknote processing apparatuses according to this embodiment described above directly detect the movement amount of the banknotes by the two-dimensional movement amount detection sensor, the conventional banknote processing apparatus measures the movement amount of the banknotes. The configuration does not include the pulse encoder installed in

  The present invention is not limited to the above-described embodiment as it is, and in the implementation stage, the component may be modified and embodied without departing from the spirit of the invention, or a plurality of components disclosed in the above-described embodiment. Various inventions can be formed by appropriately combining the above. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine the component covering different embodiment suitably.

DESCRIPTION OF SYMBOLS 1 Banknote identification apparatus 21 Entrance sensor 42 Drive pulley 43 Driven pulley 44 Banknote conveyance belt 45A thru | or 45D Press roller 50 Two-dimensional movement amount detection sensor 62 Banknote conveyance roller 65 Press roller 71 Banknote identification sensor 100 Marker 111 Conveyance state discrimination | determination part 111A Calibration Processing unit 111B Skew detection unit 111C Slip detection unit 112 Identification unit 112A Identification address correction processing unit 112B Identification processing unit 113 Motor control unit 120 Memory 121 Measuring roller

Claims (3)

A bill recognition device for identifying the authenticity of a bill,
A transport means for transporting a bill inserted from the insertion slot;
A measurement index provided in the conveying means;
The movement amount data of the conveying means is detected from the reflected light irradiated with the measurement index on the conveying means, and the movement of the banknote from the reflected light irradiated on the banknote when the conveying means is conveying the banknote. Movement amount detection means for detecting amount data;
Reference movement amount calculation means for calculating a reference movement amount per unit output of the movement amount detection means based on movement amount data of the conveyance means detected by the movement amount detection means;
Measurement position acquisition means for acquiring a measurement position for reading feature data on the banknote based on the reference movement amount calculated by the reference movement amount calculation means;
Feature data detection means for detecting feature data at the measurement position from the bill;
Reference data storage means for storing feature data at a predetermined position on the banknote as reference data;
Identification means for comparing the feature data at the measurement position detected by the feature data detection means and the reference data stored in the reference data storage means to identify the authenticity of the bill;
A bill discriminating apparatus comprising:   The banknote identification device according to claim 1, wherein the measurement index is a plurality of indices provided at a predetermined interval on a banknote transport belt or a banknote transport roller.   The movement amount detection means detects movement amount data of the measurement index until a bill inserted from the insertion slot reaches a detection position of the movement amount detection means. Item 2. A bill identifying device according to Item 2.

Images