JPH0782565B2 - Banknote data correction method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a banknote data correction method in a banknote discriminating apparatus for discriminating banknote denomination, authenticity, and the like in a cash processing machine, an automatic transaction machine, and the like. .

(Prior Art) In a conventional bill discriminating apparatus, a conveyed bill is irradiated with light from a light source, and data such as reflected light or transmitted light from an optical sensor is collected and used as discrimination data. Further, the discrimination performance of the apparatus depends on whether the discrimination data is collected under the same condition as when the standard data is collected or the collected data is normalized so as to be the same as when collected under the same condition. However, since the discrimination data causes output fluctuations due to fluctuations in the light amount of the light source and disturbances such as external temperature, these fluctuation factors are eliminated and the optical sensor output (received light) is collected under the same conditions as the standard data. There is a bill data correction method for correcting (sensor output).

Hereinafter, an example of the bill data correction method of such a conventional bill discriminating apparatus will be described.

The conventional bill discriminating apparatus makes a determination as to whether it is a genuine bill or a counterfeit bill for the conveyed bills, and only when it is determined to be a genuine bill,
Data in a predetermined range of the collected data of the genuine bills, that is, the optical sensor output value A is stored in the nonvolatile RAM, and an average value of a plurality of the genuine bills (N sheets) is calculated,
Understand the current optical sensor output status. Further, the average value is calculated in advance by multiplying the magnification E with the sensor reference output value collected in the same manner as described above at the time of collecting the standard data, so that the magnification of the amplification portion of the optical sensor output of the present apparatus becomes the current E times. It was something to do.

(Problems to be Solved by the Invention) However, in the banknote data correction method of the conventional banknote discriminating apparatus, the output of the light receiving sensor or the output of the light source cannot follow the rapid fluctuation of the disturbance, and the optical sensor output Since the data requiring correction is data from a bill, correction data corresponding to the change over time is not generated when the bill does not pass when there is a change over time in the optical sensor. Therefore, there is a drawback that the correction data cannot follow a sudden change in disturbance or a change with time of the optical sensor.

Further, considering the variation amount of the collected data such as the follow-up of the correction data and the number of passed bills, it becomes necessary to increase the allowable value of the standard data to be compared and determined with the collected data. The permissible value is a factor that greatly affects the discrimination performance. Therefore, if the permissible value of standard data also needs to be increased, there is a risk that the performance will be deteriorated.

Therefore, an object of the present invention is to provide a banknote data correction method capable of obtaining desired collection data with high accuracy without incurring a deterioration in performance of the banknote discrimination device even when there is a sudden change in disturbance or a change over time. To provide.

(Means for Solving the Problem) The banknote data correction method of the present invention detects an optical pattern of a banknote by an optical detection means, and based on the detection output data, the banknote denomination and the insertion direction, and the banknote money. In the bill discriminating apparatus for discriminating the authenticity of the kind, the maximum output level of the detection output data of the discriminated bill by the optical detecting means is detected, and the multiplication factor between the maximum output level and the reference set value is calculated, By multiplying the detection output data of the bill to be discriminated by the magnification, the detection output data by the same optical detection means as described above is corrected.

(Operation) Therefore, the maximum output level of the detection output data of the bill to be discriminated by the optical detecting means is detected, the magnification between the maximum output level and the reference set value is calculated, and the magnification is the detection output of the bill to be discriminated. Since the output data (collected data) detected by the same optical detection unit of the bill to be discriminated is corrected by multiplying the data, the output fluctuation of the light source or the light receiving sensor in the optical detection unit is corrected. The detection output data (collected data) of the bill to be discriminated can be corrected in real time. Therefore, even if there is a change over time in the output of the optical detection unit or the optical detection unit due to the disturbance of the bill discriminating apparatus, without depending on these,
Highly accurate output data can be obtained based on the optical detecting means. Further, it becomes possible to reduce the allowable value of the standard pattern used for determining the authenticity of the denomination of the bill of the bill discriminating apparatus, and the performance of the bill discriminating apparatus can be improved.

(Example) Next, this invention is demonstrated with reference to drawings.

FIG. 1 is a block diagram showing an embodiment of a bill data correction method according to the present invention.

The banknote data correction method of the present invention detects an optical pattern of a banknote by an optical detection means, and based on this detection output data, a banknote that determines the denomination and insertion direction of the banknote and the authenticity of the denomination of the banknote. This is for normalizing the detection output data of the bill to be discriminated in the discrimination device.

In FIG. 1, 1 is a light receiving sensor that irradiates a bill (not shown) conveyed in a bill discriminating apparatus with light and detects reflected light or transmitted light thereof, and 2 is a voltage photoelectrically converted by the light receiving sensor 1. An amplification unit 3 that amplifies to an optimum value, and 3 is an analog / digital conversion unit (hereinafter, A / D conversion unit) that converts the analog voltage amplified by the amplification unit 2 into a digital value at each sample timing synchronized with the speed of bills being conveyed. 4) is a register for temporarily storing the data digitized by the A / D conversion unit 3, and 5 is the RA for the data.
It is a central processing unit (hereinafter referred to as CPU) that stores standard pattern data stored in M6 or ROM7 and generates correction data by arithmetic processing.

Next, the operation of this embodiment will be described with reference to FIGS. Note that FIG. 2 is a diagram showing a sensor output waveform of the light receiving sensor 1 of FIG. 1, and FIG. 3 is a normalization processing flowchart of the CPU 5 in one optical sensor as an optical detecting means,
FIG. 4 is a flow chart showing the arithmetic processing of the CPU 5 of FIG.

First, in the bill discriminating apparatus, the conveyed bill to be discriminated is irradiated with light, and its reflected light or transmitted light (hereinafter, only reflected light will be explained) is photoelectrically converted by the light receiving sensor 1, and photoelectrically converted analog. The output is amplified to the optimum value by the amplifier 2. This amplified analog signal is A / D
The conversion unit 3 converts the digital signal into a digital signal at a sample timing synchronized with the bill conveyance speed, and the converted digital data is temporarily stored in the register 4 and the CPU 5
Thus, the digital data is stored in the RAM 6 at a predetermined address.

Here, in FIG. 2, g _i (t) is a pattern when digital data before correction of the bill to be discriminated when scanning the light receiving sensor 1 in the denomination direction i stored in the RAM 6 is expressed as a continuous function. Is. Where i = 1,2, ..., j,
i represents the type number in the denomination direction, and the banknotes to be discriminated are 3 yen denominations of Japanese yen (10,000 notes, 5000 notes, 1000 notes), 4 directions (front,
(Face-up, reverse, reverse)), j = 12. Also, g _i
(T) is data when the light amount of the light source of the optical sensor that irradiates the bill to be discriminated is reduced.

Further, f _i (t) in the figure is a standard pattern when the light receiving sensor 1 is scanned in the same denomination direction i as in the case of g _i (t). g _i (t) is the standard pattern f _i (t)
On the other hand, the output is reduced due to the data collected under the different condition that the light amount of the light source of the optical sensor is reduced.

Next, the CPU 5 in the method for correcting the discriminated bill data g _i (t)
The signal processing by will be described with reference to FIG.

First, t = 0 to n of the standard pattern f _i (t) in advance (t: maximum value of sample timing value, n: sample timing value)
The maximum output level V ₀ is detected and the maximum output level V ₀ is stored in the ROM 7 as a sensor output reference value. Next, for the collected data g _i (t) of the bill to be discriminated, the maximum output level V _a of the collected data g _i (t) at t = 0 to n is detected (steps S1 and S2 in FIG. 3) _o. V _a is the value of g _i (t) at t = t _a . Here, the standard pattern f _i (t)
When the magnification C of the to-be-determined banknote data g _i (t) is obtained with the maximum output level of each pattern as a standard, a relational expression such as C = V _o / V _a (1) is established. Therefore, the optical sensor output data g _i (t) of the bill to be discriminated is corrected by the relational expression shown in the following equation (2).

g ′ _i (t) = C · g _i (t) (2) Then, in step S3 of FIG. 3, the ratio of the sensor output reference value V _O to the maximum output level V _a of the collected data of the bills to be discriminated. That is, the scale factor C is calculated, and the collected data g _i (t) is multiplied by the scale factor C in step S4 in FIG.
_{Find i} (t).

On the other hand, the above-described, the calculation of the calculation of the detection the magnification C of the maximum output level V _a of the discrimination bill data g _i (t), the discrimination bill data after correction (normalized data) g 'i _(t)
A calculation processing flowchart by the CPU 5 is shown in FIG. That is, as can be seen from steps S1 and S2, the time when the bill validator starts to operate is set to t = 0, and the maximum output level V _a is also set.
Start from V _a = 0. And the device is up and running,
In step S3, it is determined whether or not the collected data g _i (t) of the bill to be discriminated at the sample timing t is larger than the already-obtained V _a before the current sample timing t, and g
_{If i} (t) is not larger than V _a , the process proceeds to step S4,
Also with g _i (t) is g in a previous rather than value current sample timing t as V _a step S5 is greater than V _{a i} (t), i.e. as V _a = g _i (t) , And proceeds to step S4.

If the sample timing value t is not the maximum value n in step S4, the sample timing value is incremented by +1 in step S6, that is, the operation after step S3 is repeated at the next sample timing value. Then, when the sample timing value t reaches the maximum value n in step S4, the process proceeds to step S7. The above is the maximum output level detection of the collected data of the bills to be discriminated. Next, in step S7, the final value of V _a used before the shift to step S7 (this value is the largest) is used, and V ₀ is divided by this value of V _a to obtain the magnification C. (Magnification C
Calculation). Next, in step S8, the collected data g
_The correction data g ′ _i (t) is calculated by multiplying _i (t) by the scale factor C (calculation of normalized data g ′ _i (t)).

Further, (when the optical sensor is scanned with respect to a bill, obtained from an optical sensor (light receiving sensor), the entire detection output data for the bill) all data of scanning lines in one optical sensor in the present invention the maximum output level from V _o Is detected and the maximum output level V _o is set to the standard level necessary for normalizing the bill to be discriminated by the optical sensor, in the case of the conventional method in which the standard level for normalization detection is a fixed reading position. , When the reference level reading position of bills is accidentally soiled, the reference level does not reach the desired level,
It is possible to eliminate the problem that normalization cannot be performed accurately.
Therefore, in the present invention, even if the white part of the background of a part of the bill on the scanning line is contaminated when the optical sensor is scanned, the other white part of the background can be used, so that the optical sensor output reference level is accurate. Can be detected, and stable normalization becomes possible.

As can be seen from the above description, the present invention detects the maximum output level V _a of the detection output data of the bill to be discriminated by the optical sensor, and the maximum output level V _a and the preset sensor output reference value V _o . calculating a magnification _{C (C = V o / V} a), to correct the detection output data g _i of the discrimination bill (t) by multiplying the magnification detection output data g _i of the discrimination bill (t) It was done like this. Such processing is performed for each bill conveyed and for each optical sensor. By doing so, the detected output data (collected data) g _i (t) of the bill to be discriminated can be normalized in real time with respect to the output fluctuation of the light source in the optical sensor or the light receiving sensor 1. Therefore, even if there is a change in the output of the optical sensor due to a disturbance of the bill validator (including a sudden disturbance) or a change with time of the optical sensor, the output data from the optical sensor is highly accurate and does not depend on them. Things are obtained.
Further, the allowable value of the standard pattern data used for determining the authenticity of the denomination of the bill of the bill discriminating device can be reduced, and the performance of the bill discriminating device can be improved.

In the present embodiment, the reflected light sensor is used as the optical sensor, and the case where the reflected light is applied is described. However, the present invention is not limited to this, and a transmissive sensor or the like is used as the optical sensor. Of course, the same can be applied to.

(Effects of the Invention) As described above, according to the present invention, the detection output data (collected data) of the bill to be discriminated is real-time normalized with respect to the output fluctuation of the light source and the light receiving sensor in the optical detecting means. Therefore, even if there is a change in the output of the optical detection means or a change with time of the optical detection means due to the disturbance of the bill discriminating device, the output data based on the optical detection means is high without depending on them. You can get the precision.

Further, according to the present invention, it is possible to reduce the allowable value of the standard pattern used for the authenticity determination of the denomination of the bill of the bill validator, and the performance of the bill validator can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a bill data correction method according to the present invention, FIG. 2 is an output waveform diagram of the light receiving sensor 1 of FIG. 1, and FIG. 3 is a normalization process of the CPU 5 in one optical sensor. A flow chart, FIG. 4 is a flow chart showing the arithmetic processing of the CPU 5 of FIG. 1 ... Receiving sensor, 3 ... A / D converter, 5 ... CPU, 6 ...
… RAM, 7 …… ROM.

Claims (1)

[Claims] 1. A bill discriminating apparatus for detecting an optical pattern of a bill by an optical detecting means and discriminating the amount of bills, the inserting direction, the authenticity of the amount of bills, etc. based on the detected output data. By detecting the maximum output level of the detection output data of the bill to be discriminated by the dynamic detection means, calculating the magnification of the maximum output level and the reference set value, and multiplying the magnification by the detection output data of the bill to be discriminated. A bill data correction method, characterized in that the detection output data of the to-be-determined bill by the same optical detection means as that described above is corrected.