JPH0850671A - Correction device for paper money detecting sensor output - Google Patents

Abstract

PURPOSE:To improve the paper money detection capability and to considerably improve the reliability of counterfeit discrimination by correcting the variance or the paper money detection sensor output due to respective factors. CONSTITUTION:A read means which discharges the charged electric charge of an integrator 33 by a discharging means to successively reads in the output value at the end of discharge of the integrator 33 and that after charge of the integrator 33 and a calculating means which subtracts the just preceding output value at the time of the end of discharge from the output value after charge which is read in by the read means are provided, and the output of a paper money detecting sensor S4b is corrected based on the subtraction value in the calculating means. A means which corrects the variance of the paper money carrying speed and a means which corrects the error due to the change of the quantity of light of the light source of the paper money detecting sensor S4b are provided besides.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention processes a sensor output signal in a bill validator, and more particularly, a detection sensor receives fluorescent light reflected (or passed) by applying UV (fluorescent) lamp light to a bill. The present invention relates to a light-receiving signal correction device for determining the authenticity of a banknote (in particular, a banknote having a fluorescent substance, a banknote having no fluorescence as a genuine banknote; used for excluding a copy on paper).

[0002]

2. Description of the Related Art Judgment of authenticity of banknotes having a fluorescent substance is
Generally, the following method is used. First, UV
The lamp light is applied to the bill, and the reflected fluorescence is received by the light receiving sensor. Then, the output of the light receiving sensor is integrated by an integrating circuit for a certain period of time, and the authenticity is determined based on the integrated value. At that time, the constant of the integrating circuit is reduced to make a determination when the envelope exceeds the threshold value.

Further, the above-mentioned determination process is carried out after the motor for conveying bills is activated and after waiting until the rotation of the motor has stabilized. That is, since the correction for the fluctuation of the bill transport speed has not been performed conventionally,
When the transport speed is slow, the time until the specified mechanical clock is input is long, and when the transport speed is fast, the specified mechanical clock is short, so the fluorescence signals at the same banknote location are integrated. In that case, as a result, the longer the integration time, the higher the output voltage. As a result, since an appropriate value cannot be obtained when the transport speed is fluctuating, it is necessary to wait until the rotation of the motor stabilizes after starting. In addition, an AC motor must be used to rotate it at a constant speed, and even when it is used, feeding is started after the conveying speed is stabilized by using a clutch, a brake and the like. Also, a DC motor could not be used to make the device smaller.

Further, when the output of the fluorescence sensor drops to some extent due to secular change or the like, accurate determination processing cannot be performed. In such a case, conventionally, the life of the fluorescent sensor or the UV lamp is estimated, and the fluorescent sensor or the UV lamp is appropriately replaced with a new one.

[0005]

By the way, in the detection method using the envelope as described above, a slight difference occurs in the detected value when the position where the signal waveform is sampled is deviated (sampling is performed at a point). Therefore, there is a drawback in that the authenticity determination reliability is poor. For this reason, when sampling the data of a bill, the charge is discharged at every unit transport time of the bill for which the constant of integration is increased, a new integration is started, and the integrated value is calculated at each unit transport time of the bill. A / D conversion is performed, and then the integrated charges are discharged, and integrated for the next unit transport time. In this case, if the discharge is slow, some electric charge remains in the integrating capacitor, and the sampling voltage gradually rises.

Further, as described above, there is a drawback that a correct detection value cannot be obtained when there is a change in the bill conveyance speed. Therefore, even if there is a change in the conveyance speed, the output of the integration circuit does not change. Was desired. Furthermore, conventionally, when the output of the fluorescent sensor drops to some extent, it may be replaced with a new one even if the fluorescent sensor or UV lamp has not reached the end of its life, which shortens the maintenance period of the device, There was a problem that it resulted in increased expenses required for customer maintenance.

The present invention has been made under the circumstances as described above, and an object of the present invention is to improve the output of the bill detection sensor caused by each of the above factors without adding a circuit or a sensor. It is an object of the present invention to provide a bill detection sensor output correction device that can correct the bill and improve the bill detection ability and can significantly improve the reliability in the authenticity determination.

[0008]

The present invention relates to a bill detection sensor output correction device for correcting the output of a detection sensor in a bill identification device, and the above object of the present invention is to provide a conveyance means for conveying a bill, A fluorescent sensor having a light source for irradiating the banknote with light and a light-receiving sensor for receiving fluorescence from the banknote, an integrator for integrating the output of the fluorescent sensor for a certain period of time, and discharging the charge of the integrator In a bill detection sensor output correction device in a bill discriminating device, which is provided with a discharging means and is adapted to determine the authenticity of the bill based on the output of the fluorescent sensor, the discharging means discharges the charge accumulated in the integrator. Read means for sequentially reading the output value of the integrator at the end of discharge and the output value of the integrator after charging; and the charge means read by the read means. And an arithmetic means for subtracting the output value at the discharge end of the immediately preceding the output value after is achieved by correcting the output of the bill detecting sensor on the basis of the subtraction value in the calculating means.

[0009] Further, a transport means capable of transporting banknotes at different speeds on the transport path, a transport pulse generating means for generating a pulse according to the transport distance of the banknote by the transport means, and the banknote being irradiated with light. With a light source that has a light source that receives fluorescence from the bill, an integrator that integrates the output of the fluorescence sensor for a certain period of time, and a charge of the integrator for each generation of a predetermined number of the pulses. In the bill detection sensor output correction device in the bill discriminating device, which is provided with a discharging unit that discharges the bill, and determines whether the bill is true or false based on the output of the fluorescent sensor, the pulse counts the predetermined number. Means for measuring the generation time of the pulse; and the discharge value of the integrator by discharging the charge accumulated in the integrator by the discharging means and the previous value. Reading means for sequentially reading output values of the integrator after charging; first computing means for subtracting an output value immediately before the end of discharge from the output value after charging read by the reading means; Second calculating means for calculating the fluctuation amount of the transportation speed based on the pulse generation time measured by the time measuring means and the reference transportation speed of the bill,
This is achieved by correcting the output of the bill detection sensor based on the subtracted value by the first calculation means and the fluctuation amount calculated value by the second calculation means.

Further, a transport means for transporting the bill, a light source for irradiating the bill with light, and a fluorescence sensor having a light receiving sensor for receiving fluorescence from the bill, and an output of the fluorescence sensor for a predetermined time. Banknote detection sensor output correction in a banknote recognition device that includes an integrator that integrates and a discharge unit that discharges the charge of the integrator, and that determines the authenticity of the banknote based on the output of the fluorescent sensor In the apparatus, the discharging means discharges the charge accumulated in the integrator, and the reading means sequentially reads the output value of the integrator at the end of discharging and the output value of the integrator after charging; and the reading means. First computing means for subtracting the output value at the end of the discharge immediately before from the read output value after the charging; a light amount monitoring sensor for detecting the light amount of the light source; A second calculation means for calculating a variation of the light amount of the light source based on the output of the sensor, and the bill detection based on the subtraction value of the first calculation means and the variation calculation value of the second calculation means. It is achieved by correcting the output of the sensor.

[0011]

In the present invention, the voltage error caused by the discharging operation of the integrator that integrates the output of the bill detecting sensor (fluorescent sensor) can be corrected, so that the voltage that is not fully discharged remains in the integrating capacitor. Appropriate data can be obtained even if a rise occurs. Also, since proper data can be obtained even if the discharge time of the integration capacitor is shortened, shortening the discharge time can widen the data collection range for the banknote search surface and improve the detection capability of the banknote detection sensor. It becomes possible.

Further, since the output value of the integrator can be corrected to an appropriate value in accordance with the bill transport speed, proper data can be obtained even when the transport motor rises or the mechanical load causes a change in the transport speed. You will be able to get it.

Further, since the sensor output can be corrected according to the change in the light emission amount of the fluorescent sensor, it is possible to obtain proper data even when the output of the fluorescent sensor changes due to a change in ambient temperature or a change over time. become able to.

[0014]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 2 is a diagram showing an example of the external configuration of a paper sheet counting processor, which is the premise of the present invention, and FIG.
FIG. 5 is a vertical sectional view showing an example of the mechanical system, and FIG. 5 is a block diagram showing a schematic configuration of an electric circuit system. First, with reference to these drawings, an outline of a paper sheet counting processor, which is a premise of the present invention, will be described.

As shown in the external view of FIG. 2, a counting start button, an operation button for designating a speed mode and the like, a count value, etc. are displayed on the front surface of the housing 23 of the paper sheet counting processor 1. An operation panel 22 including a display unit for operating the display, an alarm lamp, and the like is provided, and the hopper 11 is provided above the operation panel 22 and the stacker 20 is provided below the operation panel 22, respectively. A power switch 24 is provided below the side wall of the housing 23. Then, the bills accumulated in the hopper unit 11 are fed into the housing 23 by the rollers 12, 13, and 14 by pressing the counting start button, and after the bills are discriminated and counted, the stacker fan 18 is used. The sheets are discharged and accumulated in the stacker 20.

Next, the internal mechanism will be described with reference to FIG. 3. The kicker roller 12 and the feed roller 1 in the housing 23 will be described.
The 3 and the gate roller 14 constitute a feeding means for feeding the banknotes 10 accumulated in the hopper unit 11. Further, the feed roller 13, the roller 15 facing the feed roller 13, the acceleration roller 16, and the flywheel 16
The accelerating roller 17 to which a is attached constitutes a conveying unit that conveys the banknote 10 fed by the feeding unit. Each part of the feeding means and the conveying means is driven by the DC motor M1 (see FIG. 5). The friction portion 13a of the feed roller 13 is configured to be fed and rotated by a predetermined angle (for example, 4 degrees) from the friction portion 12a of the kicker roller 12, and the acceleration rollers 16 and 17 are also provided.
Is a DC motor M1 and a one-way clutch (not shown)
Are linked by.

The guide plates 19a and 19b form a conveying path for guiding the conveyed bill 10 to the stacker fan 18. The stacker fan 18 takes in the banknotes 10 conveyed by the conveying means one by one into the blades and accumulates them in the stacker 20. The stacker fan 18 is configured to be driven by an independent DC motor M2 (see FIG. 5).

[0018] Here, each of these components, when the peripheral speed of the kicker roller 12 and _{V 1,} the peripheral velocity _{V 1} of the feed roller 13, the peripheral speed is 1.2V ₁ acceleration rollers 16, 17,
Circumferential speed of the stacker fan 18 is configured such that V _1/3.

A hopper sensor S1, a fluorescence detection sensor unit S4, a counting sensor S2, and a stacker sensor S3 are arranged in the transport section from the hopper unit 11 to the stacker unit 20, and the peripheral portion of the flywheel 6a is provided with:
An encoder S5 is provided. The outline of the function of each sensor will be described below.

The hopper sensor S1 detects the presence or absence of the banknote 10 in the hopper section 11.

The fluorescence detecting sensor unit S4 irradiates the bill 10 conveyed by the conveying means with UV lamp light, receives the reflected fluorescence and outputs a detection signal. Here, a configuration example of the fluorescence detection sensor unit S4 will be described.

FIG. 4 is a sectional view showing an example of the structure of the fluorescence detection sensor unit S4. As shown in FIG. 4, a UV lamp (cold-cathode UV lamp) 41 as a light source and an ultraviolet ray are provided in the unit container 44. A filter 42 that passes only light in a specific frequency range, a dichroic mirror 43 that coats a reflection surface that reflects the light source but passes the received light without reflecting it, and transmits visible light, and A light receiving sensor (photodiode) PD1 for converting into a current is provided, and a light source monitoring sensor PD2 for detecting the light amount of the light source is provided in the UV lamp 41.
Is provided in the vicinity of. The wirings to the UV lamp 41, the light receiving sensor PD1, the light source monitoring sensor PD2 and the like are gathered on the substrate 45 and connected to the outside by the connector 46. Hereinafter, the devices (PD1, 41 to 46) related to the output of the detection signal of the light receiving sensor PD1,
Called "fluorescent sensor S4a", light source monitoring sensor PD2
The devices (PD2, 45, 46) related to the above are referred to as "light amount monitoring sensor S4b".

Here, with reference to FIG.
The light of a specific wavelength that has passed through the filter 42 from the UV lamp 41, which is a light source, is incident on the A surface of the dichroic mirror 43 and reflected on the B surface, and the reflected light passes through the C surface and the bill Irradiate 10. The fluorescence emitted by the banknote 10 enters from the C surface of the dichroic mirror 43, passes through the B surface, is received by the light receiving sensor PD1, and the received light information is converted into a current and output. Then, the detection signal is corrected by a correction process described later, and the authenticity of the banknote 10 is determined based on the corrected detection signal.

The light receiving element S2 'and the light emitting element S2 "(see FIG. 3)
The reference sensor) constitutes a counting sensor S2 that counts the number of bills 10 conveyed by the above-mentioned conveying means.

The stacker sensor S3 detects the presence / absence of banknotes 10 in the stacker 20.

The encoder S5 detects the convergence by detecting the slits formed at regular intervals on the peripheral portion of the flywheel 6a which also serves as the slit disk. Thereby, the payout speed and the transport speed of the banknote 10 are calculated.

Next, the configuration of the electric circuit system will be described with reference to FIG. The control unit 21 includes a signal processing unit including a CPU, a memory, an A / D converter, etc., a sensor input unit, a mechanical clock counting unit input from the encoder S5, a clock unit, and the like. In the control unit 21, the operation panel 22
Based on the signals input from the sensors S1 to S5, control of the entire counting processor (drive control of the DC motors M1 and M2, abnormality processing, etc.) and bill discrimination / counting processing are performed. The correction process of the received light signal of the fluorescence sensor S4a according to the present invention is performed by the correction means in the control unit 21. In addition, the bill conveyance speed mode is 500
There are three modes of sheet / minute, 1000 sheets / minute, and 1500 sheets / minute, but the present invention is not limited to these three modes. Although a DC motor is used as an example of each drive motor, it goes without saying that an AC motor or the like may be used.

The banknote detection sensor output correction device of the present invention having such a configuration will be described in detail. FIG.
FIG. 5 is a block diagram showing an example of the hardware configuration of the bill detection sensor output correction device of the present invention. From the fluorescence detection sensor unit S4 shown in FIG. 4, the fluorescence detection signal SDa of the fluorescence sensor S4a and the light amount monitoring sensor are shown. The light amount detection signal SDb of S4b is output, and the smoothing circuits 31a and 31b are output.
It is input to 31b. The fluorescence detection signal SDa from the fluorescence sensor S4a is smoothed by the smoothing circuit 31a and sent to the offset adjusting circuit 32. On the other hand, the light amount monitoring sensor S
The light amount detection signal SDb from 4b is smoothed by the smoothing circuit 31b, sent to the offset adjusting circuit 32, converted into a digital value by the A / D converter 34b, and converted into a CP value.
It is sent to U30. The offset adjustment circuit 32 performs offset adjustment (described later) on the smoothed fluorescence detection signal SDa. The offset-detected fluorescence detection signal is integrated for a certain period of time by the integrator 33, amplified by an amplifier circuit (not shown), converted into a digital value by the A / D converter 34a, and sent to the CPU 30.

In the CPU 30, the light amount detection data SDb '
A control command UVD is sent to the control circuit 35 based on the above, and the fluorescent lamp 41 is passed through the control circuit 35 and the inverter 36.
Is adjusted (described later) so that the light emission amount of is a proper amount. CP
In U, the following correction process is performed based on the digitized fluorescence detection data SDa ′ and the light amount detection data SDb ′, and the authenticity of the bill is determined based on the corrected fluorescence detection data.

In the present invention, the detection sensor (fluorescence sensor S4
In order to improve the detection capability of a), the variation of the fluorescence sensor output caused by each factor is corrected. There are roughly three items to be corrected, and these correction processes will be sequentially described.

Example of correction of circuit error: After the carry motor is turned on, the discharging means in the integrator 33 causes the discharge means in the integrator 33 to carry out a predetermined amount of carry pulses (in this embodiment, every five mechanical timing pulses) in the integrator 33. The electric charge stored in the integration capacitor of is discharged. The waveform of the input signal voltage of the A / D converter 34a at that time is, for example, as shown in FIG. This discharge control is performed by turning on an analog switch connected to the integrating capacitor via a resistor for each carrier pulse. In this embodiment, the time constant at this time is 3
90Ω × 0.1 μF = 39 μsec. However,
When attempting to obtain data on the entire bill search surface, data cannot be collected during the discharge time td shown in FIG. If this discharge time td is shortened, the data collection time will be longer, but sufficient discharge cannot be performed due to the characteristics of the IC. Therefore, in the case where a constant DC voltage is input because charges that cannot be completely discharged remain in the integrating capacitor, as shown in FIG. 13, the A / D converter 3
Since the input signal voltage of 4a will gradually rise,
Accurate data cannot be obtained. As a result, if this data is used as it is, there will be a problem in the bill authenticity determination process. Therefore, in the present invention, the integrator 33
Then, the voltage that cannot be discharged at each reset is corrected by the following method.

In the CPU 30, the output value of the integrator 33 (at the timing when the analog switch is turned on) is discharged at the time when the charging of the integrating capacitor of the integrator 33 is discharged at every predetermined amount of carrier pulse and charging is started. The A / D conversion value) is read, a predetermined amount of carrier pulse is counted, and then the output value of the integrator 33 is read. Then, this reading operation is repeated for each discharge cycle, and the output value at the end of discharge and the output value after charging are sequentially read. At this time, the output value at the end of the immediately preceding discharge is subtracted from the output value after charging, and the subtracted value is stored in the memory. That is, V1 ′ and V1, shown in FIG.
The values of V2 'and V2, ... Are read sequentially and V1 "= V1
-V1 ', V2 "= V2-V2', ...
The i-th data is collected by the following formula 1.

[0033]

## EQU1 ## Vi "= Vi-Vi 'where Vi' is the A / D converted value of the integrated voltage when the integrating capacitor is discharged, and Vi is the A / D of the integrated voltage when 5 mechanical clocks have elapsed. It is a D conversion value.

By this process, the voltage that cannot be discharged at each reset is corrected by the integrator 33, and the true / false judgment process (to be described later) of the bill based on the calculated value Vi ″ is performed to determine the true value. The reliability of false judgment is improved.

Example of transport speed correction: A mechanical clock, which is a transport pulse generation means, is generated according to the transport distance of a bill. Converted to the rotation speed of the gear head of the motor, the bill conveyance speed is, for example, 500 rpm, 1000
In the case of rpm and 1500 rpm, the banknote transport speed is as shown in FIG. 15, and the data sampling cycle at every 5 mechanical clocks is 225 for each.
It becomes 0 μsec, 1125 μsec, and 750 μsec. That is, when the transport speed changes, the interval at which the mechanical clock is generated changes. Therefore, in the present invention,
The detected data is corrected by the following method.

As the procedure 1, the integration time is converted into the case of the reference transport speed (1000 rpm) by the following processing.
Here, data from the discharge end time point (= charge start time point) to the next discharge end time point (for example, V1′-
Data between V2 ': hereinafter referred to as "zone data")
In, if the i-th zone data is Di ′, then C
The PU 30 calculates Di ′ by the following equation 2.

[0037]

## EQU00002 ## Di '= Vi ".times. (Ct / ti) where Vi" is the calculated value by the above-mentioned equation 1, and Ct is
This is the number of counts of the internal clock counted by the CPU 30 during a predetermined amount of carrier pulse interval (5 mechanical clocks) in the case of feeding at the standard carrier speed. Further, ti is an internal clock count value of the CPU 30 when counting 5 mechanical clocks.

As a procedure 2, the output of the fluorescence sensor S4a is calculated from the zone data value Di 'when the medium (banknote) is present to the zone data value Do when the medium is absent by the following equation 3.
Is subtracted to correct the noise component that is always superimposed on the output.

[0039]

## EQU00003 ## Di "= Di'-Do Here, Do is Do = (Voi-Voi ') * (Ct
/ To) is the zone data value when there is no medium. However, a predetermined time (for example,
Sampling is performed for 20 seconds, and the largest value in the sampling is considered to be the noise weight, and the second largest value as the quasi-maximum value is set as the offset voltage Do (to is the internal clock count value of the CPU at that time).

By the processing of the above procedure 1, even when the conveyance speed changes due to the start-up of the motor or the mechanical load, the output value of the integrator is corrected to an appropriate value. By the processing, the noise component that is always superimposed on the output will be corrected.

Correction of sensor sensitivity / temperature: Since the UV lamp has a property that the output gradually increases until 100 seconds after the start of energization, correction is necessary for counting during this period. In addition, correction is necessary even when the output changes due to changes in ambient temperature or changes over time. FIG. 16 shows the rising characteristics of the fluorescent sensor. Due to the characteristics of the sensor, the voltage changes as shown in the graph immediately after the power is turned on. In this embodiment, the offset adjusting circuit 32 is adjusted by using a variable resistor (not shown) so that the voltage value of the integrator 33 when there is no medium becomes a constant voltage value (180 mV). When calculating the detection data, the A / D conversion value (180
For mV, "9") is subtracted.

However, as described above, the output voltage of the fluorescent sensor may become unstable due to the temperature environment, the aging of the UV lamp, and the like.
If the / D conversion value is subtracted, an error will occur.
Therefore, in the present invention, the light amount of the fluorescent lamp 41 is monitored by the light amount monitoring sensor S4b and is corrected using the output value SDb 'of the monitoring sensor S4b. Further, during standby (after turning on the power of the counting processor and before starting the counting process), the output voltage of the monitoring sensor S4b becomes the reference value (2.5 V in this embodiment) as shown in the graph of FIG. UV lamp 4
The light emission amount is adjusted by the lighting control of 1. By stabilizing the light emission amount of the UV lamp 41 by this adjustment processing, the variation of the output value SDa ′ of the fluorescence sensor S4b due to the environmental change such as the temperature change is indirectly corrected. Details of these correction processes will be described in the following description of the operation example.

Next, along with an operation example of the bill counting processor 1,
The above-mentioned correction processes (1) to (4) will be described in detail with reference to the flowcharts of FIGS. When the main power supply is turned on by the power switch 24 of the bill counting machine 1, the CPU 30 in the control unit 21 starts the elapsed timer (step S101), and causes the UV lamp 41 to be duty cycled through the control circuit 35 and the inverter 36. It is turned on at a ratio of 100% (step S102). Then, the light amount monitoring sensor S4
The A / D conversion value SDb 'of the detection signal of b is read (step S103), and it is determined whether or not the detection value SDb' is a set value (2.0 V in this embodiment) or more (step S).
104), if it is equal to or greater than the set value, ON / OFF control of the inverter 36 is performed at a predetermined duty ratio, and the outputs of the detection sensors S4a and S4b are reference values (2.5 in this embodiment).
V).

Explaining with reference to FIG. 17, first, it is judged whether or not the input signal voltage of the A / D converter 34b is 1.0 V or higher, and it reaches 1.0 V or higher within the specified time. If not, the process is considered to be abnormal and the process is stopped. If it is 1.0 V or more, the fluorescence sensor S4a
In order to prolong the lamp life, it is determined that the light source environment is ready, and from the time when the voltage value becomes equal to or higher than the set value (2.0 V), as shown in FIG.
Then, the inverter is turned on for one cycle and turned off for two cycles to control the lighting of the UV lamp 41, and the output of the light amount monitoring sensor S4b is adjusted to the reference value (2.5 V). The correction process of the fluorescence detection data based on the output of the light amount monitoring sensor, which will be described later, is performed with the above reference value as a reference (step S105).

Subsequently, in the control section 21, the hopper sensor S
It is determined whether or not the bill 10 is placed on the hopper 11 based on the detection signal 1 (step S106). If not, the process returns to step S103 and the above lighting control is repeated, so that the bill 10 is placed. If there is, it is determined whether or not the counting start button is pressed (step S1).
07). If the count start button is pressed,
The UV lamp 41 is turned on at a duty ratio of 100% (step S108), and the data SDa 'of the fluorescent sensor S4a is collected for a predetermined time. In this embodiment, 20 ms
In the meantime, sampling is performed every 1125 μs, and data in a state where the medium (banknote 10) does not exist is collected. And 20m
The largest one between s is considered to be noise superposition, and a quasi-maximum value among the collected voltages is set as the offset voltage Do.
However, the offset voltage Do is a value obtained by correcting an error due to a change in the transport speed of the banknote 10 (described later) (step S109).

Then, in the control section 21, the motors M1 and M are
The banknotes 10 accumulated in the hopper unit 11 are driven by the feeding means 2 and fed out by the feeding means, and the bills 10 fed out are conveyed by the conveying means (step S110). In the control unit 21,
Interrupt processing for each predetermined clock described later (step S20
0) fluorescence sensor S4a and light amount monitoring sensor S4b
It is determined whether or not the detection data reading process of 1 is completed (step S111), and if the interrupt process is not completed, the counting process of the banknotes 10 and the monitoring process of the conveyance abnormality and the like are performed. The techniques of the counting process and the abnormality monitoring process are the same as the conventional ones, and thus the description thereof will be omitted (step S112).

Here, the interrupt processing executed every predetermined clock (5 mechanical clocks in this embodiment) will be described with reference to FIGS.
It will be described according to the flowchart of Now, assuming the case of the n-th interrupt processing, the control unit 21
First, the value ti of the internal timer is read, the timer is reset and restarted (step S201), and A / D conversion of the detection signal of the fluorescent sensor S4a is started (step S202). In the control unit 21, after waiting for the conversion time of the A / D converter 34a (step S203), the A / D conversion value Vi of the fluorescence sensor S4a (A / D conversion value of the mountain portion of the zone data; V1 of FIG. 14). , V2, ...) is read (step S204). Then, the short circuit of the analog switch is turned on to start discharging the integrating capacitor in the integrator 33 (step S205), and the light amount monitoring sensor S4b is started.
A / D conversion of the detection signal of is started (step S20).
6). The control unit 21 waits for the conversion time of the A / D converter 34b (step S207) and then reads the A / D conversion value Vsi of the light amount monitoring sensor S4b (step S2).
08).

Subsequently, after waiting for the discharging time of the integrating capacitor which has started discharging in step S205, A / D conversion of the detection signal of the fluorescent sensor S4a is started (step S).
209, 210). Then, after waiting for the conversion time of the A / D converter 34a (step S211), the short circuit of the analog switch is turned off to end the discharge of the integrating capacitor (step S212), and the A of the fluorescent sensor S4a is A.
The / D conversion value Vi + 1 '(the A / D conversion value of the valley portion of the zone data; V2', V3 ', ... Of FIG. 14) is read (step S213), and the nth interrupt processing is ended.

When the data collection by the interrupt processing is completed (FIG. 6: step S111), the control unit 21 corrects the detected data. Here, there are two methods for correcting the detection data, and the correction processing (step S300) will be described later. When the correction of the detection data is completed, the control unit 21 determines whether or not one banknote 10 has passed (step S113). If the banknote 10 has not passed, the process returns to step S111 and the above process is repeated to pass one banknote. If so, the fluorescence detection data D1 to Dm after correction processing (m is the number of valid data) are rearranged in order from the maximum value, and the maximum value Xmax of the rearranged data Xmax to X1 is taken as the noise convolution weight. Consider and exclude,
The average value Ds of the m-1 pieces of data is calculated by the following mathematical expression 4 and used as the true / false determination value (step S114).

[0050]

## EQU00004 ## Ds = (Xmax-1 + ... + X2 + X1) / (m-1)

Then, the authenticity determination value Ds is compared with the threshold S (step S115), and the authenticity determination value Ds is compared with the threshold S.
If it is less than, it is determined as a fake note and the process proceeds to the abnormal process (step S116), and if the authenticity determination value Ds is the threshold value S or more, it is determined as a genuine note (step S117). And
It is checked whether or not the counting process has been completed for all the banknotes 10 (step S118), and if not completed, the process returns to step S111, and the authenticity determination process and counting of the banknote 10 to be conveyed next is performed. If the process is repeated and all banknotes 10 have been processed, the motor M
The drive of 1 and M2 is stopped and the operation of the bill counting processor 1 is ended.

FIG. 10 is a flow chart showing a first example of the correction processing of the detection data in step S300, and the first example of the correction processing will be described with reference to FIG. The speed of the carry motor M1 changes depending on the speed mode and the length of the bill, and also changes after the motor is started until the rotation becomes constant. Therefore, in the CPU 30, the above equation 2
Thus, the integration time of the detection data V is converted into the case of the reference transport speed, and the error due to the fluctuation of the transport speed is corrected (step S301).

Then, the fluorescence sensor S is obtained by the above-mentioned equation 3.
4a output, zone data value Di ′ when medium is present
Subtract the zone data value Do when there is no medium from
The noise component that is always superimposed on the output is corrected. Here, Do is the offset voltage Do calculated in the process of step S109 of FIG. 6 (see the mathematical formula described in the supplementary explanation of the above-mentioned mathematical expression 3) (step S302).

Next, using the value Vsi of the light amount monitoring sensor when Di ″ is calculated, the error of the fluorescence sensor output with respect to the environmental change caused by the sensor sensitivity and the temperature is calculated by the following equation 5.
Is corrected (step S302), and the process returns to the main process.

[0055]

## EQU00005 ## Di = Di ".times. (Vk / Vsi) where Vk is the reference voltage value (2.5 in this embodiment) of the light amount monitoring sensor S4b by the lighting control in step S105.
V).

Next, a second example of the detection data correction processing in step S300 will be described with reference to the flowchart of FIG. In the second example, the offset voltage value of the offset adjustment circuit 32 described in the above correction process is not used, but the offset voltage value is obtained from the output of the light amount monitoring sensor S4b using the conversion table. The offset voltage value of the offset adjustment circuit 32 is canceled prior to the correction process, or the offset adjustment circuit 32 itself is deleted from the hardware configuration.

FIG. 18 is a diagram showing the correspondence between the monitor voltage Vsi and the offset voltage Voffi. Corresponding values as shown in FIG. 18 are set in advance in the table. First, the CPU 30 determines whether or not a predetermined time (3 minutes in this embodiment) or more has elapsed since the UV lamp 41 was turned on (step S31).
1), if not elapsed, the standard offset voltage (18
0 mV is set as the offset voltage (Vsi = 180 mV) (step S312), and if 3 minutes or more has elapsed, the monitoring voltage Vsi of the optical monitoring sensor S4b is set as the offset voltage (step S313).

Subsequently, the offset value Voffi corresponding to Vsi is obtained from the conversion table (step S314),
The correction is performed by the following equation 6 (step S315), and the process returns to the main process.

[0059]

## EQU00006 ## Di = (Vi-Voffi) .times. (Vk / Vsi) where Vk is the reference voltage value of the light amount monitoring sensor S4b controlled by the lighting control of the UV lamp 41 (2.
5V).

By the above processing, the error of the fluorescence sensor output signal due to the fluctuation of the characteristics of the integrated circuit and the carrying speed,
Furthermore, it is possible to automatically correct the error in the fluorescent sensor output signal due to the characteristics of each sensor, temperature change, etc.
It becomes possible to obtain highly reliable data for banknote identification.

In addition to the above correction, the present invention corrects the data timing deviation caused by the displacement of the count sensor S2 for detecting the count timing and the fluorescence sensor S4a.

It is desirable that the data detection positions (positions of the light receiving sensors) of the counting sensor S2 and the fluorescence sensor S4a be the same position, but as shown in the arrangement example of FIG. 3, in view of physical restrictions and maintainability. Therefore, it may be necessary to shift the layout. FIG. 19A is a diagram showing output waveforms of the respective sensors when the fluorescent sensor S4a and the counting sensor S2 are arranged while being shifted by Lmm, and Ph is the counting sensor S2.
When Pt detects the leading edge of the bill, Pt is counting sensor S
2 indicates the time when the rear end of the bill is detected. In this case, in the fluorescence sensor S4a, the data corresponding to the leading end of the banknote is Lmm (Phase data Yn
The data before the Pt) and the data corresponding to the rear end of the bill is the data before Lmm (zone data Yn) before Pt. Therefore, if the data at the time of detection by the counting sensor S2 is used as it is, data corresponding to the actual bill cannot be obtained.

Therefore, in the present invention, as shown in FIG. 6B, the deviation is corrected so as to match the state when the counting sensor S2 and the fluorescence sensor S4a are at the same position. FIG. 20 shows a buffer for storing each zone data (A / D conversion value) of the fluorescence sensor output.
Is a buffer for cyclically storing the zone value until the counting sensor S2 detects a banknote (in the present invention,
It is called a "ring buffer"). Also, buffer B
Is a buffer that sequentially stores the zone values after the time when the bill is detected by the counting sensor S2. Thus, in addition to the fixed area, a ring-shaped storage area is provided in advance. The value of the zone data number Yn detected during the physical shift (Lmm) is set in advance.

The CPU 30 starts collecting the data of the fluorescence sensor output when the counting start button is pressed and the zone is set in the ring buffer A until the time when the counting sensor S2 detects the bill (Ph point in FIG. 19A). Save values cyclically. Then, when the counting sensor S2 detects the front end portion (point Ph) of the bill, the subsequent zone values are sequentially stored in the buffer B. And CPU
At 30, the valid data is from the zone data before Yn units at the leading end of the banknote to the zone data before Yn units at the rear end (Pt point). For example, the address R4 in FIG.
After storing the zone data of the banknote, when the leading edge of the bill is detected by the counting sensor S2, the data string is R5, R6.
The order is R1, ..., R4, and these data in the ring buffer A correspond to Yn zone data from the leading edge of the bill.

The data stored in each of the buffers A and B in the above-described deviation correction processing is the data that has been subjected to the other corrections described above, and the deviation correction is the detection data of the light amount monitoring sensor S4b. Is also done.

[0066]

As described above, according to the bill detection sensor output correction device of the present invention, the voltage error caused by the discharge operation of the integrator that integrates the output of the fluorescence sensor can be corrected. Reliability in false judgment is improved. Further, since the discharge time can be shortened and the data collection range for the banknote search surface can be expanded, it is possible to improve the detection capability of the banknote detection sensor.

Furthermore, since the output value of the integrator can be corrected to an appropriate value according to the bill conveyance speed, it is affected even when the conveyance speed changes due to the rise of the conveyance motor or mechanical load. It becomes possible to provide a bill validator that does not have a bill.

Further, since the sensor output can be corrected in accordance with the change in the light emission amount of the fluorescent sensor, the bill discriminating apparatus is not affected even when the output of the fluorescent sensor changes due to the ambient temperature change or the secular change. Will be able to provide. Further, it is possible to correct the data timing deviation caused by the displacement between the counting sensor and the fluorescence sensor, and the sensor can be arranged at an arbitrary position.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration example of a bill detection sensor output correction device of the present invention.

FIG. 2 is a diagram showing an example of an external configuration of a paper sheet counting processor that is a premise of the present invention.

FIG. 3 is a vertical cross-sectional view showing an example of a mechanical system of a paper sheet counting processor, which is a premise of the present invention.

FIG. 4 is a cross-sectional view showing a configuration example of the fluorescence detection sensor unit of FIG.

FIG. 5 is a block diagram showing a schematic configuration of an electric circuit system of a paper sheet counting processor, which is a premise of the present invention.

FIG. 6 is a part of a flowchart for explaining correction processing by the device of the present invention.

FIG. 7 is a continuation of the flowchart of FIG.

8 is a part of a flowchart for explaining an interrupt processing routine in FIG.

FIG. 9 is a continuation of the flowchart of FIG.

FIG. 10 is a flowchart illustrating a first example of a correction processing routine in FIG.

FIG. 11 is a flow chart for explaining a second example of the correction processing routine in FIG.

FIG. 13 is a time chart for explaining correction processing by the device of the present invention.

FIG. 14 is a time chart for explaining a correction process by the device of the present invention.

FIG. 15 is a time chart for explaining correction processing by the device of the present invention.

FIG. 16 is a time chart for explaining correction processing by the device of the present invention.

FIG. 17 is a time chart for explaining a correction process by the device of the present invention.

FIG. 18 is a diagram showing an example of setting contents of a conversion table used in correction processing by the device of the present invention.

FIG. 19 is a time chart for explaining a correction process by the device of the present invention.

FIG. 20 is a diagram showing a configuration example of a data storage buffer used in a correction process by the device of the present invention.

[Explanation of symbols]

 1 Paper Sheet Counting Processor 10 Banknote 11 Hopper 12 Kicker Roller 12a, 13a Friction Part 13 Feed Roller 14 Gate Roller 15 Roller 16, 17 Accelerating Roller 18 Stacker Fan 19a, 19b Guide Plate 20 Stacker 21 Control Unit 22 Operation Panel 23 Housing Body 30 CPU 31a, 31b Smoothing circuit 32 Offset adjustment circuit 33 Integrator 34a, 34b A / D converter 35 Control circuit 36 Inverter S1 Hopper sensor S2 Counting sensor S3 Stacker sensor S4 Fluorescence detection sensor unit S4a Fluorescence sensor S4b Monitoring sensor 41 UV lamp 42 Filter 43 Dichroic Mirror 44 Unit Container 45 Substrate 46 Connector

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] November 22, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration example of a bill detection sensor output correction device of the present invention.

FIG. 2 is a diagram showing an example of an external configuration of a paper sheet counting processor that is a premise of the present invention.

FIG. 3 is a vertical cross-sectional view showing an example of a mechanical system of a paper sheet counting processor, which is a premise of the present invention.

FIG. 4 is a cross-sectional view showing a configuration example of the fluorescence detection sensor unit of FIG.

FIG. 5 is a block diagram showing a schematic configuration of an electric circuit system of a paper sheet counting processor, which is a premise of the present invention.

FIG. 6 is a part of a flowchart for explaining correction processing by the device of the present invention.

FIG. 7 is a continuation of the flowchart of FIG.

8 is a part of a flowchart for explaining an interrupt processing routine in FIG.

FIG. 9 is a continuation of the flowchart of FIG.

FIG. 10 is a flowchart illustrating a first example of a correction processing routine in FIG.

FIG. 11 is a flow chart for explaining a second example of the correction processing routine in FIG.

FIG. 12 is a time chart for explaining correction processing by the device of the present invention.

FIG. 13 is a time chart for explaining correction processing by the device of the present invention.

FIG. 14 is a time chart for explaining a correction process by the device of the present invention.

FIG. 15 is a time chart for explaining correction processing by the device of the present invention.

FIG. 16 is a time chart for explaining correction processing by the device of the present invention.

FIG. 17 is a time chart for explaining a correction process by the device of the present invention.

FIG. 18 is a diagram showing an example of setting contents of a conversion table used in correction processing by the device of the present invention.

FIG. 19 is a time chart for explaining a correction process by the device of the present invention.

FIG. 20 is a diagram showing a configuration example of a data storage buffer used in a correction process by the device of the present invention.

[Explanation of reference numerals] 1 paper sheet counting processor 10 banknote 11 hopper 12 kicker roller 12a, 13a friction part 13 feed roller 14 gate roller 15 roller 16, 17 acceleration roller 18 stacker fan 19a, 19b guide plate 20 stacker 21 control part 22 Operation Panel 23 Housing 30 CPU 31a, 31b Smoothing Circuit 32 Offset Adjustment Circuit 33 Integrator 34a, 34b A / D Converter 35 Control Circuit 36 Inverter S1 Hopper Sensor S2 Counting Sensor S3 Stacker Sensor S4 Fluorescence Detection Sensor Unit S4a Fluorescence Sensor S4b Monitoring sensor 41 UV lamp 42 Filter 43 Dichroic mirror 44 Unit container 45 Substrate 46 Connector

Claims (3)

[Claims] 1. A transportation means for transporting a bill, a fluorescence sensor having a light source for irradiating the bill with light, and a light receiving sensor for receiving fluorescence from the bill, and an output of the fluorescence sensor for a predetermined time. Banknote detection sensor output correction in a banknote recognition device that includes an integrator that integrates and a discharge unit that discharges the charge of the integrator, and that determines the authenticity of the banknote based on the output of the fluorescent sensor A reading means for discharging the charge stored in the integrator by the discharging means, and sequentially reading the output value of the integrator after discharging and the output value of the integrator after charging; Compensating the output of the banknote detection sensor based on the subtracted value in the computing means, and the computing means for subtracting the output value at the end of the discharge just before from the output value after the charging read by the means. A bill detection sensor output correction device characterized in that. 2. Conveying means capable of conveying bills at different speeds on a conveying path, conveying pulse generating means for generating a pulse in accordance with the conveying distance of the bills by the conveying means, and irradiating the bills with light. With a light source that has a light source that receives fluorescence from the bill, an integrator that integrates the output of the fluorescence sensor for a certain period of time, and a charge of the integrator for each generation of a predetermined number of the pulses. A bill detection sensor output correction device in a bill identification device configured to determine the authenticity of the bill based on the output of the fluorescent sensor, and the discharge means to discharge the A clocking means for timing the generation time of a predetermined number of pulses; discharging the charge of the integrator by the discharging means, and outputting the output value of the integrator at the end of discharge and the integration. Reading means for sequentially reading output values after charging of the container; first calculating means for subtracting an output value at the end of the discharge immediately before from the output value after charging read by the reading means; Second calculation means for calculating the fluctuation amount of the conveyance speed based on the pulse generation time counted by the means and the reference conveyance speed of the bill, the subtraction value in the first calculation means and the second calculation A bill detection sensor output correction device, characterized in that the output of the bill detection sensor is corrected based on the calculated variation amount by the means. 3. A conveyance means for conveying a bill, a fluorescent sensor having a light source for irradiating the bill with light and a light receiving sensor for receiving fluorescence from the bill, and an output of the fluorescent sensor for a predetermined time. Banknote detection sensor output correction in a banknote recognition device that includes an integrator that integrates and a discharge unit that discharges the charge of the integrator, and that determines the authenticity of the banknote based on the output of the fluorescent sensor A reading means for discharging the charge stored in the integrator by the discharging means, and sequentially reading the output value of the integrator after discharging and the output value of the integrator after charging; First calculation means for subtracting the output value at the end of the discharge immediately before from the output value after the charging read by the means; a light amount monitoring sensor for detecting the light amount of the light source; Second calculation means for calculating a variation of the light quantity of the light source based on the output of the bill detection sensor based on the subtraction value of the first calculation means and the variation calculation value of the second calculation means. A bill detection sensor output correction device characterized in that the output of the bill detection sensor is corrected.