JP2012073713A - Paper money identification device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable highly accurate detection of skewed or sliding paper money.SOLUTION: A paper money identification device includes: a motor for driving a conveyance belt or a conveyance roller for conveying paper money; a pulse encoder for outputting a pulse in sync with rotation of the motor; a two-dimensional movement amount detection sensor that is provided on the conveyance belt or at a position facing the conveyance roller through a paper money conveyance passage, and detects movement amounts of both the conveyance belt or the conveyance roller and conveyed paper money; and a conveyance state determination unit for obtaining reference data composed of information on the movement amount and a movement direction of the conveyance belt or the conveyance roller for a predetermined pulse of the pulse encoder and paper money conveyance state information composed of information on the movement amount and a movement direction of paper money being conveyed for the predetermined pulse of the pulse encoder, on the basis of output from the two-dimensional movement amount detection sensor, and detecting skewing and sliding of the paper money by comparing the reference data with the paper money conveyance state information.

Description

  The present invention relates to a bill validator.

  Conventionally, a bill recognition device is mounted on a vending machine or the like. The bill recognition device transports a bill inserted from a bill insertion slot with a transport belt or a transport roller and takes it into the device. During the transport, a bill sensor such as an optical sensor or a magnetic sensor provided along the bill transport path is used. The identity sensor identifies the authenticity and type of the banknote.

  A pulse encoder is attached to the shaft of the drive motor that drives the conveyance belt or the conveyance roller of the banknote identification device, and the characteristic data of the banknote detected by the identification sensor in synchronization with the pulse output from the pulse encoder, By comparing with the feature data stored in the memory, the authenticity and type of the banknote are identified, and the number of pulses of the pulse encoder until the banknote passes the position of a specific sensor is counted to determine the length of the banknote. It is made to judge.

  In the memory of the banknote identification device, banknote characteristic data used for comparison with the characteristic data detected by the identification sensor is stored in advance. When the inserted banknote is identified as not a genuine note in the above identification, an operation of rotating the drive motor in the reverse direction and returning the banknote is performed.

  In such a banknote identification device, the conveyance belt or the conveyance roller or the conveyance parts that the banknote comes into contact with, or a wet banknote, a broken banknote, or a shabby banknote without a strain is 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, when slipping occurs, the position of the detection result by the identification sensor shifts and a defective identification occurs.

  In Patent Document 1, in order to solve these problems, in a banknote identification device mounted on a vending machine or the like, a slip of a banknote is generated by a roller pulse attached to a pressing roller and a motor pulse attached to a motor shaft. A technique for performing identification corresponding to the above is disclosed.

  On the other hand, in Patent Document 2 and Patent Document 3, 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 2005-41623 A JP 2005-206307 A

  However, in the technique disclosed in Patent Document 1, slipping occurs in the pressing roller itself, and the slipping of the banknote may not be detected accurately. In addition, the skew could not be detected.

  In addition, in the techniques disclosed in Patent Document 2 and Patent Document 3, since there is an error (variation) in the two-dimensional movement amount detection sensor, it is not possible to detect skew or slip of the paper sheet with high accuracy. .

  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 calculated by reading the optical image from the lens with a CCD and using DSP (Digital
Due to the principle of the two-dimensional movement detection sensor that detects the movement distance in two directions with the 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. Say. 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.

  This invention is made | formed in view of such a condition, The objective is to provide the banknote identification device which can detect the inclination and slip of a banknote with high precision.

In order to achieve the above object, the banknote recognition apparatus of the present invention includes:
A motor for driving a conveyor belt or a conveyor roller for conveying banknotes;
A pulse encoder that outputs a pulse in synchronization with the rotation of the motor;
A two-dimensional movement amount detection sensor that is provided at a position facing the conveyance belt or the conveyance roller across a banknote conveyance path, and detects a movement amount of both the conveyance belt or the conveyance roller and the banknote to be conveyed; ,
Based on the output of the two-dimensional movement amount detection sensor,
Reference data consisting of information on the moving amount and moving direction of the conveying belt or the conveying roller per predetermined pulse of the pulse encoder,
Each of the transfer status information of the banknotes consisting of information on the movement amount and the movement direction of the banknotes being transferred per the predetermined pulse of the pulse encoder,
A conveyance state determination unit that detects the inclination and slip of the banknote by comparing the reference data with the state information of the banknote.
According to the present invention, it is possible to increase the inclination and slip of the banknote using the movement amount and movement direction of the conveyance belt or the conveyance roller per predetermined number of pulses of the pulse encoder and the movement amount and movement direction of the banknote per the same number of pulses. It can be detected with accuracy.

  Moreover, the banknote identification apparatus of this invention synchronizes with the rotation of the measurement member driven in conjunction with the conveyance belt or conveyance roller which conveys a banknote, the motor which drives the said conveyance belt or the said conveyance roller, and the said motor. A pulse encoder that outputs a pulse and a position on the conveyor belt or at a position facing the conveyor roller across a banknote transport path, and detects the amount of movement of both the measuring member and the banknote to be transported 2 Based on the output of the two-dimensional movement amount detection sensor, the reference data including the movement amount and movement direction information of the measuring member per predetermined pulse of the pulse encoder, and the pulse encoder Each of the movement amount information of the bill being conveyed per predetermined pulse and the conveyance state information of the bill consisting of information on the movement direction are obtained, respectively, and the reference data and the previous By comparing the status information of the banknote, characterized in that it and a transfer state judgment unit for detecting inclination and slipping of the bill. According to the present invention, the tilt and slip of a bill are detected with high accuracy using the amount and direction of movement of the measuring member per predetermined number of pulses of the pulse encoder and the amount and direction of movement of the bill per the same number of pulses. can do.

  According to the present invention, it is possible to detect the inclination and slip of a banknote with high accuracy.

It is principal part fracture | rupture sectional drawing of the banknote identification device which concerns on the 1st Embodiment of this invention. It is a figure which shows the structural example of a two-dimensional movement amount detection sensor. It is a side view which shows the outline of the banknote conveyance means and banknote identification means of the banknote identification device. It is a top view which shows the outline of the banknote conveyance means and banknote identification means of the banknote identification device. It is a block diagram which shows the function structural example of the control part of the banknote identification device. It is a flowchart explaining operation | movement of the banknote identification device which monitors the conveyance state of a banknote. It is a top view which shows the outline of the banknote conveyance means and banknote identification means of the banknote identification device which concerns on the 2nd Embodiment of this invention. It is a flowchart explaining other operation | movement of a banknote identification apparatus.

[First embodiment of the present invention]
<Configuration example of banknote identification device>
First, the basic configuration of the banknote recognition apparatus according to the first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a cutaway sectional view of a main part of a banknote recognition apparatus according to a first embodiment of the present invention.

  The banknote recognition apparatus 1 of FIG. 1 is provided in a vending machine, for example. The banknote recognition apparatus 1 is provided in the apparatus main body 3 which is a housing | casing provided with the banknote insertion slot 2, and the apparatus main body 3, and the banknote inserted in the banknote insertion slot 2 is followed along the banknote conveyance path | route in the apparatus main body 3. Banknote transporting means 4 for transporting the banknotes, banknote identification means 5 for identifying the authenticity and denomination of the banknotes transported by the banknote transporting means 4, and a stacker 6 for storing the banknotes identified by the banknote identification means 5 as authentic. It consists of.

  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. The driving pulley 42, the driven pulley 43, and the driven rollers 45A to 45D correspond to transport rollers.

  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 on the basis of a drive signal from the control unit described later 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 is rotated. 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 61 is provided at a position facing the banknote transport belt 44 across the banknote transport path. The two-dimensional movement amount detection sensor 61 is a sensor having a function similar to that of 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 example of the two-dimensional movement amount detection sensor 61.

  The two-dimensional movement amount detection sensor 61 includes a light source 81, a two-dimensional light receiving element array 83, and a lens 82 for converging 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. The principle of detection of the movement amount by the two-dimensional movement amount detection sensor 61 is a known technique as described in Japanese Patent Application Laid-Open No. 2005-41623 and the like, and thus detailed description thereof is omitted.

  The banknote identification device 1 is equipped with such a two-dimensional movement amount detection sensor 61, so that each movement amount of the banknote transported with the banknote transport belt 44 (a movement amount in the X direction and a movement amount in the Y direction). The amount of received light reflected from each of the banknote transport belt 44 and the banknotes to be transported is acquired, and the tilt and slip of the banknotes being transported are detected.

  The two-dimensional movement amount detection sensor 61 is disposed in the vicinity of the banknote transport belt 44 that is hung on the driven pulley 43. By disposing the two-dimensional movement amount detection sensor 61 at a position close to the driven pulley 44 and the drive pulley 42 in this way, the distance between the two-dimensional movement amount detection sensor 61 and the bill transport belt 44 becomes relatively constant. The amount of movement of the bill or bill transport belt 44 can be detected with high accuracy.

  Next, the banknote conveyance means 4, the banknote identification means 5, and the two-dimensional movement amount detection sensor 61 of the banknote identification apparatus 1 according to the first embodiment will be described in detail with reference to FIGS.

  FIG. 3 is a side view showing the outline of the banknote transporting means 4 and the banknote recognition means 5 of the banknote recognition apparatus 1 shown in FIG. 1, and FIG. 4 is a top view showing the outline of the banknote transporting means 4 and the banknote recognition means 5. It is.

  As shown by the white arrow # 1 in FIG. 3, the banknote inserted into the banknote insertion slot 2 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 into the apparatus pass through the positions of the driven roller 45A and the driven roller 45B, and reach the detection position of the two-dimensional movement amount detection sensor 61 indicated by the tip of the white arrow # 2. Further, it passes through the position of the driven roller 45 </ b> C and passes through the position where the identification optical sensor 71 including the light emitting element 51 and the light receiving element 52 is provided. When the bill passes through the identification optical sensor 71, the bill recognition device 1 determines the authenticity of the bill based on the output of the identification optical 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 identification optical sensors 71 are provided side by side in a direction orthogonal to the transport direction. In the example of FIG. 3, a two-dimensional movement amount detection sensor 61 is provided on the lower bill conveyance belt 44 side.

  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 motor 41 is provided with a motor pulse encoder 91 that outputs a pulse signal in synchronization with the rotation of the motor 41. The upper driven pulley 43 and the lower driven pulley are connected by a shaft (not shown).

  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 example of the control unit.

The CPU 101 functioning as a control unit implements a conveyance state determination unit 111, an identification unit 112, and a motor control unit 113 by executing a predetermined program stored in the memory 120 in advance.
The conveyance state determination unit 111 determines the slip and inclination of the banknote based on the information acquired by the two-dimensional movement amount detection sensor 61.

  The discriminating unit 112 discriminates the authenticity and denomination of the bill based on the output signal from the motor pulse encoder 91, the output signal from the bill discriminating means 5, and information from the transport state discriminating unit 111. The motor control unit 113 controls conveyance of bills in the receiving direction, conveyance in the return direction, and stopping. The transport state determination unit 111 includes a measurement unit 111A, a skew detection unit 111B, and a slip detection unit 111C, and the identification unit 112 includes an identification address correction processing unit 112A and an identification processing unit 112B.

  Each time the measuring unit 111A detects that a bill has been inserted based on the output signal of the entrance sensor 21, the motor pulse encoder 91 is based on the output of the two-dimensional movement amount detection sensor 61 in the absence of the bill. Reference data consisting of information on the amount and direction of movement of the conveying belt 44 or conveying roller per predetermined pulse is obtained and stored in the memory 120. Based on the amount of received light acquired by the two-dimensional movement amount detection sensor 61, the measurement unit 111A obtains a reference amount of received light, and stores the reference data and the reference amount of received light in the memory 120 in association with each other.

  The measuring unit 111 </ b> A detects that the inserted bill has reached the position of the two-dimensional movement amount detection sensor 61 based on the change in the amount of received light. When it is detected based on the change in the amount of received light that the bill has reached the position of the two-dimensional movement amount detection sensor 61, the measuring unit 111 </ b> A is based on the output of the two-dimensional movement amount detection sensor 61. The conveyance state information of the banknote which consists of the information of the movement amount and movement direction of the banknote being conveyed per predetermined pulse is obtained.

  The skew detection unit 111B detects the skew of the banknote by comparing the movement direction of the banknote included in the obtained banknote 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 bill by comparing the amount of movement of the bill included in the obtained bill conveyance state information with the amount of movement of the reference data stored in the memory 120. Information on the skew detected by the skew detection unit 111B and information on the slip 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 of the identification unit 112 corrects the identification address of the bill conveyed by the bill conveyance belt 44 based on the skew obtained by the skew detection unit 111B and the slip obtained by the slip detection unit 111C. To do.

  The identification processing unit 112B, for example, includes the feature data of each position of the banknote given in advance to the identification processing unit 112B and the banknote characteristic data after the identification address correction detected by the identification optical sensor 71. Match and identify the authenticity and type of banknotes. 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.

<Regarding the processing of the conveyance state determination unit 111>
Reference data acquisition method, acquisition of banknote conveyance state information after the banknote reaches the position of the two-dimensional movement amount detection sensor 61, and skew and slippage of banknotes performed by the skew detection unit 111B and the slip detection unit 111C The detection and a method for detecting that the banknote has reached the position of the two-dimensional movement amount detection sensor 61 based on the amount of received light will be described.

(Acquisition of reference data for the transport state before banknote transport)
In a state where no bill is inserted, the movement amount in the X direction (banknote transport direction) output by the two-dimensional movement amount detection sensor 61 per predetermined number of pulses of the motor pulse encoder 91 is set to X1, Y direction (banknote transport direction). The direction reference value α1, which is a value representing the direction reference in the reference data, is obtained by the following equation (1).

  α1 = ArcTan (Y1 / X1) (1)

  Further, assuming that the total movement amount obtained by adding X1 detected during a predetermined number of pulses P1 from the motor pulse encoder 91 is Xn and the total movement amount obtained by adding Y1 is Yn, the movement amount V1 of the reference data is It is obtained by the following formula (2).

V1 = SQRT (Xn ² + Yn ² ) (2)

(Acquisition of banknote transport status information after banknote transport)
Next, how to obtain the conveyance status information of the banknotes that are transported after the banknotes reach the position of the two-dimensional movement amount detection sensor 61 will be described. The amount of movement in the X and Y directions output from the two-dimensional movement amount detection sensor 61 is Xbill and Ybill, the predetermined number of pulses is IP, and the amount of movement output by the two-dimensional movement amount detection sensor 91 in the period per IP is When the movement amount is Xbilln and Ybilln, the bill movement direction αbill is obtained from the following equation (3), and the bill movement amount V2 is obtained from the following equation (4).
αbill ＝ ArcTan (Ybill / Xbill) (3)
V2 = SQRT (Xbilln ² + Ybilln ² ) (4)

The skew of the bill is obtained from the following formula.
Skew = α1bill – α1 (5)

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

(Method of detecting that the bill has reached the position of the two-dimensional movement detection sensor 61 based on the amount of light received by the two-dimensional movement detection sensor 61)
The banknote conveyor belt 44 of the banknote identification apparatus 1 uses a black belt, and the amount of light received by the banknote conveyor belt 44 (the amount of light received by the two-dimensional movement detection sensor 61) is reflected by the banknote. Less (darker) than the amount of light received. On the other hand, the bill has a larger amount of reflection (brighter) than the bill transport belt 44 as a whole. For this reason, the measurement unit 111A of the identification state determination unit 111 detects the position of the two-dimensional movement amount detection sensor 61 when the received light amount suddenly increases with respect to the reference received light amount obtained in a state where there is no bill. Can be detected.

Next, with reference to the flowchart of FIG. 6, the process which the banknote identification device 1 monitors the conveyance state of a banknote, and detects the slip and skew of a banknote is demonstrated.
In addition, apart from this flowchart, the output signal from the identification sensor is a known method until the banknote conveyed in parallel with the process of monitoring the conveyance state of the banknote reaches and passes through the identification sensor. The feature data of the sampled and time-series banknote is acquired.

  When the entrance sensor 21 detects insertion of a banknote (Yes in step S1), the motor control unit 113 controls the motor 41 to start conveying the inserted banknote (step S2).

  Next, the measuring unit 111 </ b> A determines the conveyance belt 44 per predetermined pulse of the motor pulse encoder 91 based on the output of the two-dimensional movement amount detection sensor 61 before the banknote reaches the position of the two-dimensional movement amount detection sensor 61. The reference data consisting of the information of the movement amount and the movement direction is obtained from the equations (1) and (2) (step S3). At this time, the measurement unit 111A also acquires a reference amount of received light.

  Next, the measuring unit 111A determines whether or not the bill has reached the position of the two-dimensional movement amount detection sensor 61 based on the change in the amount of received light detected by the two-dimensional movement amount detection sensor 61 (step S4). .

  In step S4, when it is determined that the banknote has reached the position of the two-dimensional movement amount detection sensor 61 (Yes in S4), the measuring unit 111A uses the motor pulse based on the output of the two-dimensional movement amount detection sensor 61. The conveyance state information of the banknote which consists of the information of the movement amount and movement direction of the banknote currently conveyed per predetermined pulse of the encoder 91 is calculated | required by Formula (3) (4) (step S5).

  Next, the skew detector 111B compares the bill conveyance state information acquired in step S5 with the reference data to detect the skew (step S6). For example, the skew detection unit 111B compares the value obtained by the above equation (5) with a predetermined threshold, and determines that the skew is detected when the threshold is exceeded (Yes in step S6).

  On the other hand, when no skew is detected (No in step S6), the skew detection unit 111B determines whether or not slip is detected (step S7). For example, the slip detection unit 111C compares the value obtained by the above equation (6) with a threshold value, and determines that a slip has been detected when a predetermined threshold value is exceeded (Yes in step S7).

  When slip is not detected in step S7 (No in step S7), it is determined whether or not the bill has passed the position of the two-dimensional movement amount detection sensor 61 (step S8). Whether or not the bill has passed through the two-dimensional movement amount detection sensor 61 is determined based on the change in the amount of light received by the two-dimensional movement amount detection sensor 61 described above. Here, when it is determined in step S8 that the banknote has not passed the position of the two-dimensional movement amount detection sensor 61, the process returns to step S5 and the same processing is repeated. On the other hand, when it is determined in step S8 that the banknote has passed through the two-dimensional movement amount detection sensor 61 (Yes in S8), the process ends.

  When the process of monitoring the conveyance state of the banknotes is completed, the banknote recognition apparatus 1 continues sampling until the banknotes pass through the identification optical sensor 71. When the sampling is completed, the banknote conveyance is stopped and the banknotes are stopped. On the basis of the characteristic data, the banknote identification process is executed to determine the banknote denomination and authenticity.

  On the other hand, if skew is detected in step S6 (Yes in S6), or if slip is detected in Step S7 (Yes in S7), identification address correction processing unit 112A determines whether correction is possible or not. Is determined (step S9).

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

  Specifically, when slipping occurs, the sampling that is usually performed in synchronization with the pulse output from the motor pulse encoder 91 is performed in synchronization with the bill movement information from the two-dimensional movement amount detection sensor 61. The identification address is corrected as described above. Also, when skew occurs, the correction address is corrected by widening the judgment threshold (threshold used for judgment of authenticity and type of banknote) in consideration of the variation of feature data for the place where the skew exceeds the specified value. I do. Note that a standard pattern for determination on the left and right of the reference line may be prepared in advance, a standard pattern for determination corresponding to a skew may be selected, and a banknote may be identified to improve the acceptance rate. And when correction | amendment is complete | finished in step S10, it will return to step S8.

  On the other hand, when it is determined in step S9 that correction is impossible (No in S9), the motor control unit 113 controls the motor 41 to stop the conveyance of the banknote, and further reversely rotates to transfer the banknote. A return operation is performed (step S11). When the bill is returned in step S11, the process returns to step S1.

  As described above, the conveyance state of the banknotes including the reference data including the movement amount and movement direction information of the conveyance belt 44 per predetermined number of pulses of the motor pulse encoder 91 and the movement amount and movement direction information of the banknotes being conveyed. This is a case where the actual conveyance speed differs from the assumed speed due to individual differences, temperature changes, changes with time, etc. of the banknote recognition device 1 by detecting the tilt and slip of the banknotes by comparing with the information. However, it becomes possible to detect the skew and slip of the banknote with high accuracy. Further, banknote skew and slip can be detected in real time, and when a large skew or slip is detected, banknotes can be prevented from being jammed by promptly returning the banknote.

[Second embodiment of the present invention]
FIG. 7 is a diagram showing another outline of the banknote transport unit 4 and the banknote recognition unit 5 of the banknote identification apparatus 1.

  In the configuration shown in FIG. 7, a measurement member 121 that is driven in conjunction with the banknote transport belt 44 or the transport roller is provided. In the example shown in FIG. 7, a measurement member 121 is attached to a driven pulley 43 serving as a conveyance roller. The diameter of the measuring member 121 provided on the driven pulley 43 is substantially the same as the diameter of the outer periphery of the conveying belt hung on the driven pulley 43, and the measurement is performed when the motor 41 is driven and the bill conveying belt 44 starts to move. The member 121 is driven integrally with the driven pulley 43. The two-dimensional movement amount detection sensor 61 is provided at a position facing the measurement member 121 across the conveyance path.

  In the configuration of FIG. 7, the above-described two-dimensional movement amount detection sensor 61 detects the movement amounts of both the measurement member 121 and the bill to be conveyed. Based on the output of the two-dimensional movement amount detection sensor 61, the measurement unit 111A obtains reference data including information on the movement amount and movement direction of the measurement member 121 per predetermined pulse of the motor pulse encoder 91. Further, based on the output of the two-dimensional movement amount detection sensor 61, the measuring unit 111 </ b> A obtains bill conveyance state information including information on the movement amount and movement direction of the bill being conveyed per predetermined pulse of the motor pulse encoder 91. . The skew detection unit 11B and the slip detection unit 11C detect the inclination and slip of the bill by comparing the reference data with the state information of the bill.

  Thereby, compared with the case where the two-dimensional movement amount detection sensor 61 is provided on the banknote transport belt 44, the instability of the banknote transport belt 44 can be eliminated to obtain reference data, or the skew and slip of the banknote can be detected.

[Modification of this embodiment]
Next, a modified example of the banknote identification device 1 will be described. FIG. 8 is a flowchart for explaining another operation of the banknote recognition apparatus. In this modification, the mode setting is not operated every time a bill is inserted, but is operated by an administrator such as a vending machine equipped with the bill recognition device 1 before the bill is inserted. The reference data is acquired at the timing when the switch is operated.

  When it is detected that the mode setting switch is operated, the measurement unit 111A determines the movement amount of the conveyance belt 44 or the conveyance roller per predetermined pulse of the motor pulse encoder 91 based on the output of the two-dimensional movement amount detection sensor 61. Reference data including movement direction information is obtained and stored in the memory 120.

  When insertion of a banknote is detected by the entrance sensor 21 (Yes in step S21), the motor control unit 113 controls the motor 41 and starts conveying the inserted banknote (step S22). The measuring unit 111A determines whether or not the bill has reached the position of the two-dimensional movement amount detection sensor 61 based on the change in the amount of received light detected by the two-dimensional movement amount detection sensor 61 (step S23).

  When it is determined that the banknote has reached the position of the two-dimensional movement amount detection sensor 61 (Yes in step S23), the measuring unit 111A determines whether the bill of the motor pulse encoder 91 is based on the output of the two-dimensional movement amount detection sensor 61. The conveyance state information of the banknote which consists of the movement amount of the banknote currently conveyed per predetermined pulse and the information of a movement direction is calculated | required (step S24).

  Next, the skew detection unit 111B detects the skew by comparing the bill conveyance state information acquired in step S24 with the reference data stored in advance in the memory 120 when the mode setting switch is operated. It is determined whether or not (step S25). If no skew is detected (No in step S25), the skew detection unit 111B determines whether or not slip has been detected (step S26).

  If no slip is detected (No in step S26), the slip detection unit 111C determines whether or not the bill has passed the position of the two-dimensional movement amount detection sensor 61 (step S27), and has not passed. (No in step S27), the process returns to step S24 and the same process is repeated. On the other hand, when it is determined that the bill has passed through the two-dimensional movement amount detection sensor 61 (Yes in step S27), the process is terminated.

  On the other hand, if skew is detected in step S25 (Yes in step S25), or if slip is detected in step S26 (Yes in S26), identification address correction processing unit 112A can perform correction or not. Is determined (step S28).

  If it is determined in step S28 that the correction is possible because the skew and slip are very small (Yes in step S28), the identification address correction processing unit 112A detects the skew or slip detected by the skew detection unit 111B. The identification address is corrected according to the slip detected by the detection unit 111C (step S29). When the correction is completed in step S29, the process returns to step S27. On the other hand, when it is determined in step S28 that correction is not possible (No in step S28), in step S30, the motor control unit 113 performs a bill return operation. When the banknote is returned in step S30, the process returns to step S21.

  As described above, it is possible to detect the skew and slip of the banknote with high accuracy by detecting the state of the banknote every time the banknote is received and comparing it with the previously measured state of the banknote transport belt 44 and the like. It becomes possible. In addition, since it cannot follow the change of the state of the conveyor belt 44 or the like as compared with the first and second embodiments in which the reference data is measured every time a bill is inserted, Data measurement is periodically performed, and the reference data stored in the memory 120 is updated each time.

  In the above, it is also possible to measure the reference data by detecting the state of the measurement member 121. Further, the reference data measurement mode may be periodically set at a timing such as when the banknote identification device 1 is in a standby state, and the measurement of the reference data may be executed. Further, instead of operating the mode setting switch, the reference data measurement mode may be set when a signal is input to the CPU 101 from the outside by other means. In the above description, the reference data is acquired at the timing when the switch is operated. However, for example, it may be performed at the time of shipment as the predetermined timing before the bill is inserted.

  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.

  In the above description, the two-dimensional movement amount detection sensor 61 is not arranged in the vicinity of the driven pulley 43, but identification is performed so that the detection start position of the feature data and the measurement start position of the two-dimensional movement amount detection sensor 61 are the same. You may mount in the position of the same line as the arrangement | sequence of the optical sensor 71 for an object. In this case, a driven pulley may be added at a position where the two-dimensional movement amount detection sensor 61 is arranged in order to suppress the banknote transport belt 44 from being ramped up. In addition, in the above, by counting the number of times the skew or slip has occurred in the banknote, it is possible to notify the administrator of the vending machine of cleaning the banknote transport belt 44 at an accurate timing. Thereby, troubles, such as banknote jam, can be prevented beforehand.

  In the above description, the case where the two-dimensional movement amount detection sensor 61 is provided on the banknote transport 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.

  Moreover, in the above, although the banknote identification device which conveys a banknote with a conveyance belt was demonstrated to the example, also in the banknote identification device which conveys a conventional banknote with a conveyance roller, the movement amount of a conveyance roller and the movement amount of a banknote A two-dimensional movement amount detection sensor is arranged at a position where both of the measurement can be measured, or a measurement member is provided so as to move in conjunction with the drive of the motor that drives the conveyance roller, and at the position where both the measurement member and the bill can be measured. Even if the two-dimensional movement amount detection sensor is arranged, the present invention can be implemented.

  In addition, when the bill is not inserted (standby state), the reference data is periodically acquired every few minutes, and after the bill is inserted, only the conveyance status information of the bill is obtained. It can also be configured to execute.

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 61 Two-dimensional movement amount detection sensor 71 Optical sensor for identification 101 CPU
111 Conveyance State Discriminating Unit 111A Reference Data Measuring 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

Claims (2)

A motor for driving a conveyor belt or a conveyor roller for conveying banknotes;
A pulse encoder that outputs a pulse in synchronization with the rotation of the motor;
A two-dimensional movement amount detection sensor that is provided on the conveyance belt or at a position facing the conveyance roller across a bill conveyance path and detects the movement amount of both the conveyance belt or the conveyance roller and the bill to be conveyed. When,
Based on the output of the two-dimensional movement amount detection sensor, reference data comprising information on the movement amount and movement direction of the conveying belt or the conveying roller per predetermined pulse of the pulse encoder, and per predetermined pulse of the pulse encoder. The bill movement state information consisting of information on the movement amount and the movement direction of the bill being conveyed is obtained, and the inclination and slip of the bill are detected by comparing the reference data and the state information of the bill. A conveyance state determination unit;
A bill discriminating apparatus comprising: A measuring member driven in conjunction with a conveying belt or a conveying roller for conveying bills;
A motor for driving the transport belt or the transport roller;
A pulse encoder that outputs a pulse in synchronization with the rotation of the motor;
A two-dimensional movement amount detection sensor that is provided on the conveyance belt or at a position facing the conveyance roller across a banknote conveyance path, and detects a movement amount of both the measurement member and the banknote to be conveyed;
Based on the output of the two-dimensional movement amount detection sensor, reference data consisting of information on the movement amount and movement direction of the measuring member per predetermined pulse of the pulse encoder, and during the conveyance per predetermined pulse of the pulse encoder The conveyance state determination part which calculates | requires the conveyance state information of the banknote which consists of the movement amount of a banknote, and the information of a movement direction, respectively, and compares the said reference data and the state information of the said banknote, and detects the inclination and slip of the said banknote. When,
A bill discriminating apparatus comprising:

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