CN100349191C - Paper money identification device - Google Patents

Abstract

To solve the problem that discrimination capability deteriorates with time.The paper money identification apparatus comprises an insertion port 21 of a bank bill 5; a passage 22; pulleys 23 and 24, rollers 26 and 27, and a transport belt 25 for transporting the paper money 5; a sensor part 46 provided on a wall surface of the passage 22; amplifiers 35 and 45 connected to the sensor part 46; an A/D converter 37; a frequency analyzer 38 connected to an output of the A/D converter 37; a memory 41; a comparator 39; and a decision unit 42. An output signal from the A/D converter 37 is Fourier transformed by the frequency analyzer 38, and the authenticity of the paper money 5 is discriminated on the basis of the Fourier transformed waveform. Thus, the paper money identification apparatus of which the discrimination capability does not deteriorate with time is obtained.(C)2005,JPO&NCIPI.

Description

Paper money identifier

Technical field

The present invention relates to the paper money identifier that in various automation services machines such as automatic vending machine or ticket machine, uses.

Background technology

In recent years, along with the variation of peddling commodity, use the paper money identifier of the great number bank note more than 1,000 yen to be widely used with institutes such as automatic vending machine or ticket machines.On the other hand, development along with OA machines such as duplicating machine or color printers, use the trend that crime that these high-precision copy devices carry out pseudo-forge money also has growth, therewith correspondence require paper money identifier can further improve the paper money recognition ability with delinquency prevention in possible trouble.

Below, in the past paper money identifier is described.Fig. 8 is a paper money identifier block diagram in the past.In Fig. 8, transmit join on the side wall surface of passage 1 configuration red light emitting diodes 2 and infrarede emitting diode 3 with bank note, transmit configuration photodiode 4 on the opposite side wall of passage 1 at bank note.Utilize this structure, the bank note 5 that becomes identifying object by photodiode 4 in face of the time can check the optical characteristics of bank note.

In addition, configuration transmits the forwarder 6 (being made of travelling belt and roller) that passage 1 transmits bank note 5 here along bank note, sets bank note detecting device 7 at the inlet of forwarder 6, is connected to the controller 8 that is used to detect bank note position.Luminous in order to convey the join red light emitting diodes 2 and the infrarede emitting diode 3 that are provided with of wall that bank note transmits passage 1 in the suitable moment, also be connected on the controller 8.

Forwarder 6 is driven by motor 9.Motor 9 is driven by motor drive circuit 10 by controller 8.Be used on the motor 9 detect the clock-pulse generator 11 that motor 9 rotates with being connected, be connected on the controller 8.

The output signal of photodiode 4 is connected on the logarithm amplifying return circuit 12, and the output of this logarithm amplifying return circuit 12 is connected on the controller 8 by linear amplification loop 13 and AD transducer 14.In addition, the reference current of above-mentioned logarithm amplifying return circuit 12 is supplied with by DA transducer 15 slave controllers 8.In addition, reference value storer 16 and input value storer 17 also are connected on the controller 8.

Below, the action of paper money identifier in the past is described.At first, when starting paper money identifier, check that under the state of no bank note the state of each sensor carries out the benchmark of optical sensor.At first, make red light emitting diodes 2 luminous.And its output is input in the controller 8 by logarithm amplifying return circuit 12, linear amplification loop 13 and AD transducer 14 as the signal of photodiode 4.Controller 8 calculates the AD transformed value of this input voltage and shifts to an earlier date the poor of given reference values X r, according to the input value Yr of the direction that this difference is diminished with given interconversion rate change DA transducer 15.The reference current value of the output decision logarithm amplifying return circuit 12 of DA transducer 15.Therefore, change the benchmark magnification of logarithm amplifying return circuit 12, the output (input value of controller 8) that can make AD transducer 14 equates with reference values X r given in advance.

Next allow infrarede emitting diode 3 luminous,, adjust the magnification of logarithm amplifying return circuit 12, the output of AD transducer 14 is equated with reference values X ir with the input value Yir that changes DA transducer 15.

The benchmark of optical sensor so far finishes, later on by by controller 8 according to the luminous sequential of light emitting diode 2,3, change the input value of DA transducer 15, obtain given sensitivity for the wavelength of each light emitting diode 2,3.

After finishing as the benchmark of above-mentioned optical sensor, if detect the insertion of bank note 5 at the inlet bank note detecting device 7 of optical sensor portion, controller 8 actuating motors 9 also drive forwarder, introduce bank note 5.The conveying capacity of bank note 5, measure by the umber of pulse of measuring clock-pulse generator 11 generations with controller 8, transmit given distance from the bank note end, make red light emitting diodes 2 luminous at the measuring point of setting in advance, obtain the AD transformed value Sr of this moment, the AD transformed value Sir when obtaining making infrarede emitting diode 3 luminous then.The differential conversion of the installation site of red light emitting diodes 2 and infrarede emitting diode 3 is the umber of pulse that clock-pulse generator 11 produces, and the position is compensated, so that obtain the data of position much at one.

In order to discern bank note, in the process that transmits bank note 5, judge the numerical value of the AD transformed value Sir of AD transformed value Sr at the pairing red light emitting diodes 2 of a plurality of measuring points, infrarede emitting diode 3 and difference Sr-Sir thereof etc. by controller 8, whether in pressing the predefined specialized range of genuine note, synthetic determination is carried out in output with magnetic sensor etc., is genuine note or counterfeit money so that judge.

Also have, as the information of technical literature formerly of relevant this application invention, such as, known have a flat 8-7149 communique of Japanese Patent Application Laid-Open.

But, in this paper money identifier in the past, to be transformed to logarithm output amplitude information by logarithm amplifying return circuit 12 from the analog amplitude information of the bank note 5 of photodiode 4 output, after further amplifying by linear amplification loop 13 pairs of inputs carrying out ratio amplitude, be transformed to digital quantity with AD transducer 14, compare and differentiate bank note 5 according to the value of this amplitude amount information and reference value storer 16.Therefore, because the adjustment of the aging in time or logarithm amplifying return circuit 12 of light emitting diode 2,3 etc. or the temperature variation in linear amplification loop 13 and linear variation etc., it is about 20% that this amplitude amount information also changes, the problem that exists discriminating power to reduce.

Summary of the invention

The invention provides a kind of paper money identifier, has the sensor part that bank note transmits passage, is used to detect the feature of the bank note that has passed through this bank note transmission passage, carrying out bank note according to the output signal of this sensor part differentiates, it is characterized in that, the output signal of this sensor part is input in the frequency analyzer by the A/D transducer, the output of this frequency analyzer, by comparing, differentiate bank note with reference value; The output of frequency analyzer is the Fourier transform waveform.

Constitute according to this, a kind of high paper money identifier of discriminating power that can not reduce discriminating power because of the aging in time of sensor part or amplifier or influence that humidity changes can be provided.If this paper money identifier is applied in the various automation services machines such as vending machine or ticket machine, can very high degree of precision carry out that forge or true or paper money is judged and the judgement of amount of money kind etc.

Description of drawings

Fig. 1 represents the block diagram of paper money identifier in an embodiment of the present invention.

Fig. 2 represents the planimetric map of bank note.

Fig. 3 represents the time response oscillogram of bank note feature portion in an embodiment of the present invention.

Fig. 4 represents the frequency characteristic oscillogram of this bank note feature portion.

Fig. 5 represents to distinguish the 1st performance plot of genuine note and counterfeit money.

Fig. 6 represents to distinguish the 2nd performance plot of genuine note and counterfeit money.

Fig. 7 represents to distinguish the 3rd performance plot of genuine note and counterfeit money.

Fig. 8 represents the block diagram of paper money identifier in the past.

Embodiment

Below, utilize accompanying drawing that the embodiment of the invention is described.Fig. 1 represents the block diagram of paper money identifier in embodiments of the present invention.Fig. 2 represents an example of bank note 5 in addition.In Fig. 1, the paper money identifier of present embodiment, have the bank note that are provided with continuously from the insertion mouth 21 of bank note 5 and transmit passages 22 and be used to detect the sensor part of feature that transmits the bank note 5 of passage 22 through this bank note, carry out bank note according to the signal of this sensor part and differentiate.

Bottom surface in that bank note transmits passage 22 is provided with pulley 23,24.Between this pulley 23,24, travelling belt 25 is erected at its two ends.Relative respectively with pulley 23,24, roller 26,27 is set, bank note 5 folds transmission by travelling belt 25 and roller 26,27.In addition, pulley 24 is driving wheels, is connected to motor 28.This motor 28 is driven by the signal from control part 30 by motor drive circuit 29.In addition, the rotation of this motor 28 is by being connected to control part 30 and Be Controlled with clock-pulse generator 31.

Further, the sensor 32 that will enter the mouth is arranged on the inlet that bank note transmits passage 22, is connected to control part 30.In addition, above bank note drive access 22, light emitting diode 33 is set, is connected to control part 30.Face mutually with this light emitting diode 33, photodiode 34 is set, be connected to the input end of amplifier 35 in the bottom surface of bank note drive access 22.

Here, light emitting diode 33 is in the present embodiment used red light emitting diodes.Because the present invention uses following fourier transform technique, so only just can fully carry out the identification of bank note 5 with a kind of wavelength of color.Therefore, can provide small-sized and paper money identifier at a low price.In addition, because red wavelength is longer, when carrying out paper money recognition, be not easy to be subjected to the influence of using the bank note gauffer that produces to be brought because of bank note.

In order to allow this red light emitting diodes become high brightness, on the PN junction of light emitting diode, further append P layer or N layer sometimes.Like this, luminosity strengthens, and has improved the paper money recognition ability.At this moment, by appending P layer or N layer, except that red, also contain infrared colour sometimes.But, in the present invention,,, also can carry out the identification of bank note 5 by utilizing fourier transform technique even comprise this infrared colour.That is to say,, can carry out the high performance identification of low price owing to can under the situation of not using the infrared colour light filter, directly use the red light emitting diodes that comprises infrared light.

In addition, as light emitting diode 33, also can use the infrared colour light emitting diode.At this moment, not only can utilize the identification of the bank note 5 of infrared light, also can carry out the identification of the magnetic that in bank note 5, comprised.Therefore, also can carry out accurate recognition to the bank note 5 that contains magnetic information.

In addition, as light emitting diode 33, also can use blue LED.Because the blue LED wavelength is shorter, can detect the difference of transmitance according to the papery of bank note 5.Therefore, not only can discern bank note 5, also can discern the transmitance of bank note 5 by blue light.Therefore, can carry out accurate recognition to bank note 5.

Like this, light emitting diode 33 except redness, also can use infrared colour light emitting diode and blue LED., can carry out with aftertreatment easily by using light emitting diode 33 as sensor.In addition, also can realize low price.

The output of amplifier 35 is connected on square end of electronic switch 36.This electronic switch 36 can be realized with hardware, also can realize with software.Then, the public terminal of this electronic switch 36 is connected to the input end of A/D transducer 37, its output is connected to the input end of frequency analyzer 38 (following expression Fourier transformer).In addition, the output of this Fourier transformer 38 is connected to a side's of comparer 39 input end, is connected on the storer 41 by compensating circuit 40 simultaneously.

And, the output of this storer 41 is connected to another input end of comparer 39.The output of this comparer 39 is connected on the determinant 42, its output is connected on the lead-out terminal 43.Also have, from the switching signal of control part 30 output electronic switches 36.

Further, with magnetic sensor 44, be arranged side by side the bottom surface of transmitting passage 22 at bank note with photodiode 34.The output of this magnetic sensor 44 is connected on the opposing party's terminal of electronic switch 36 by amplifier 45.And, with this magnetic sensor 44 and light emitting diode 33 and photodiode 34 formation sensor part 46.In addition, control part 30, Fourier transformer 38, comparer 39, equalizing network 40, storer 41, determinant 42 are realized with software in microcomputer.

Paper money identifier to as above constituting the following describes its action.

Inlet sensor 32 1 detects bank note 5, just this detection signal is delivered to control part 30.Control part 30 makes driving circuit 29 work, rotating motor 28 with this detection signal.At this moment, the pulley 24 that is connected to motor 28 begins to rotate, and travelling belt 25 transmits bank note 5 to sensor part 46.Also have, the conveying capacity of bank note 5 detects and is delivered to control part 30 with clock-pulse generator 31 at this moment.That is to say,, measure the conveying capacity of bank note 5 by measuring from the umber of pulse of clock-pulse generator 31 outputs with control part 30.

Therefore,, use driving circuit 29 driving motors 28 simultaneously, the ad-hoc location of bank note 5 shown in Figure 2 can be sent to sensor part 46 by monitoring from the signal of clock-pulse generator 31 outputs.In addition, according to the outputting standard bank note 5 of this clock-pulse generator 31.That is, owing to pass through the transfer rate of driving circuit 29 standardization bank note 5, so can reduce the error that transfer rate causes.

Bank note 5 one arrives sensor part 46, and the light of light emitting diode 33 just sees through bank note 5 and is input in the photodiode 34.Like this, the signal that will change according to the apperance of bank note 5 is input in the photodiode 34.And this signal amplifies with amplifier 35.In addition, magnetic sensor 44, the signal that will change according to the magnetic of bank note 5 amplifies with amplifier 45.And, will be from the signal of the photodiode 34 of amplifier 35 output with from the signal of the magnetic sensor 43 of amplifier 45 outputs, carry out suitable selection with electronic switch 36 after, export to A/D transducer 37.And, be transformed to digital quantity with this A/D transducer 37.Be transformed to the signal of digital quantity, be transformed to the frequency information of fourier progression expanding method with Fourier transformer 38.That is, by fourier progression expanding method as described below, can with function f (x) arbitrarily with trigonometric function and form represent.That is, will be transformed to amplitude information at the amplitude information of time shaft at frequency axis.

$f\left(x\right)=\underset{n=1}{\overset{\&infin;}{\mathrm{\&Sigma;}}}{a}_n\sin \mathrm{nx}+{\mathrm{<figure-callout\; id="0"\; label="b"\; filenames="C20041007918300141.png"\; state="\{\{state\}\}">b</figure-callout>}}_0+\underset{n=1}{\overset{\&infin;}{\mathrm{\&Sigma;}}}{b}_n\cos \mathrm{nx}$

Wherein,

$a_n=\frac{1}{\mathrm{\&pi;}}{\&Integral;}_0^{2\mathrm{\&pi;}}f\left(x\right)\sin \mathrm{nxdx}$

${\mathrm{<figure-callout\; id="0"\; label="b"\; filenames="C20041007918300141.png"\; state="\{\{state\}\}">b</figure-callout>}}_0=\frac{1}{2\mathrm{\&pi;}}{\&Integral;}_0^{2\mathrm{\&pi;}}f\left(x\right)\mathrm{dx}$

$b_n=\frac{1}{\mathrm{\&pi;}}{\&Integral;}_0^{2\mathrm{\&pi;}}f\left(x\right)\cos \mathrm{nxdx}$

Fig. 3 represents the magnetic information of the ad-hoc location of bank note 5.In Fig. 3, transverse axis 51 express times, the longitudinal axis 52 expression amplitudes.Fig. 4 represents with Fourier transformer 38 Word message among this Fig. 3 53 to be carried out information behind the fourier progression expanding method.In Fig. 4, transverse axis 54 is frequencies, and the longitudinal axis 55 is amplitudes.The 56th, the fourier progression expanding method characteristic of Word message 53.By this fourier progression expanding method, change time shaft into frequency axis.

Fig. 5 is illustrated in the ad-hoc location of bank note 5, the performance plot of the characteristic 57 (dotting) of genuine note 70 and the characteristic 58 (representing with solid line) of counterfeit money 71.In Fig. 5, transverse axis 59 is frequencies, and the longitudinal axis 60 is amplitudes.By utilizing, can differentiate genuine note 70 and counterfeit money 71 in characteristic 57 and the bigger place 61,62,63 of characteristic 58 difference.

Fig. 6 represents the performance plot of the difference of the mean value 73 of genuine note 70 and counterfeit money 71.In Fig. 6, transverse axis 74 is frequencies, and the longitudinal axis 75 is amplitudes.Here be the lighter place of bank note 5, also can better show the feature of counterfeit money 71.That is, corresponding because genuine note 70 is intaglio inks, and the printer (inkjet color printing machine, laser printer etc.) that counterfeit money 71 uses dot matrix to form, the feature 76 of this dot matrix approximately appears at 250Hz to 350Hz.Therefore, by detecting this feature 76, can clearly distinguish genuine note 70 and counterfeit money 71.Also have, at present embodiment, its feature only occurred before 350Hz, this is owing to be subjected to comprising the restriction of the sensor part 46 of light emitting diode 33, in fact should occur the feature of dot matrix before 1KHz.

Fig. 7 represents the performance plot with the word segment feature of 100Hz standardization genuine note 70 and counterfeit money 71.In Fig. 7, transverse axis 81 is frequency numbers, and the longitudinal axis 82 is amplitudes.Here, the characteristic that compares the literal portion of bank note 5.The 83rd, the characteristic of genuine note 70, the 84th, the characteristic of counterfeit money 71.In such word segment, the feature of performance genuine note 70 and counterfeit money 71 more than 150Hz.The frequency of choice criteriaization is 100Hz, is the frequency stabilization because of this scope, and is not easy to have influence on the difference that amount of money kind is produced.

In addition, to the judgement of the amount of money kind of bank note 5,,, differentiate amount of money kind according to the difference of its waveform according to fourier progression expanding method to the ad-hoc location of the amount of money kind of expression bank note 5 etc.

Like this, with comparer 39 relatively in the value of the storer 41 of the oscillation amplitude change of frequency axis and Memory Reference value.And, judge genuine note 70 and counterfeit money 71 and amount of money kind with determinant according to its comparative quantity.And, its output is exported from lead-out terminal 43.Also have, the Fourier-transformed signal of this moment is used from the transfer rate standardization of the bank note 5 of clock-pulse generator 31 outputs.Therefore, the difference to the bank note transfer rate compensates.

More than show, according to paper money identifier of the present invention, with frequency analyzer the output signal of A/D transducer is carried out Fourier transform, can judge the true and false of bank note according to this Fourier transform waveform, like this, a kind of paper money identifier can be provided, can not reduce discriminating power owing to the influence aging in time or that humidity changes of sensor and amplifier.And, owing to there not be in the past simulation process, and the employing digital processing, be not easy to be subjected to the influence of noise etc.Further, owing to do not need to resemble the D/A transducer that adopts logarithmic amplifier the conventional art adjustment that gains, perhaps adopt the good linear amplification loop of rectilinearity, thereby can make circuit reduction and miniaturization.

Claims (15)

1, a kind of paper money identifier has the sensor part that bank note transmits passage, is used to detect the feature of the bank note that has passed through this bank note transmission passage, carries out bank note according to the output signal of this sensor part and differentiates, it is characterized in that,

The output signal of described sensor part is input in the frequency analyzer by the A/D transducer, and the output of described frequency analyzer by comparing with reference value, is differentiated bank note;

The output of described frequency analyzer is the Fourier transform waveform.

2, paper money identifier according to claim 1 is characterized in that,

According to the difference of described Fourier transform waveform, can distinguish bank note of making by intaglio ink and the bank note of making by the dot matrix printing.

3, paper money identifier according to claim 1 is characterized in that,

With the waveform character from 250Hz to 1KHz in the described Fourier transform waveform, differentiate the true and false of bank note.

4, paper money identifier according to claim 1 is characterized in that,

According to described Fourier transform waveform, when differentiating forge or true or paper money,, differentiate the amount of money kind of bank note by the output of identification bank note ad-hoc location.

5, paper money identifier according to claim 1 is characterized in that,

Described Fourier transform waveform is with the time of transmitting passage through described bank note, to the bank note standardization.

6, paper money identifier according to claim 1 is characterized in that,

Described reference value is stored in the storer.

7, paper money identifier according to claim 6 is characterized in that,

The reference value of storing in the described storer compensates with the output of described frequency analyzer.

8, paper money identifier according to claim 1 is characterized in that,

Described sensor part is by light emitting diode with receive the optical sensor that the photodiode of this luminous output is formed.

9, paper money identifier according to claim 8 is characterized in that,

Described light emitting diode, only the light emitting diode by a kind of color forms.

10, paper money identifier according to claim 8 is characterized in that,

Described light emitting diode is a red light emitting diodes.

11, paper money identifier according to claim 8 is characterized in that,

Described light emitting diode is the red light emitting diodes that contains infrared light.

12, paper money identifier according to claim 8 is characterized in that,

Described light emitting diode is a blue LED.

13, paper money identifier according to claim 8 is characterized in that,

Described sensor part further comprises magnetic sensor, by the output of the described optical sensor of suitable switching and the output of described magnetic sensor, carries out the differentiation of bank note.

14, paper money identifier according to claim 1 is characterized in that,

Described transmission passage further possesses travelling belt, possesses the motor that drives described travelling belt.

15, paper money identifier according to claim 14 is characterized in that,

Possess the clock-pulse generator that is connected to described motor, monitor the position of bank note according to its output.

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