JPH02108185A - Discriminating device for paper or the like - Google Patents

Abstract

PURPOSE:To make proper corrections even if pattern detecting means have large variation in characteristics by correcting pattern detection errors due to the temperature characteristics of the pattern detecting means and other factors by the pattern detecting means. CONSTITUTION:A pattern signal obtained by a pattern detecting means 5 include an error factor due to the temperature characteristics, etc., of the pattern detecting means 5, but this is corrected by the correction arithmetic of a CPU 12 using a pattern correcting value to obtain a corrected pattern signal. Then this corrected pattern signal is compared with a reference pattern signal stored in a reference pattern signal storage means 14 to discriminate the paper, etc., correctly. In this case, the pattern correcting value is set by the individual pattern detecting means 5 on the basis of the reference pattern signal. Consequently, the signal which is corrected according to the characteristics of the respective pattern detecting means 5 is obtained.

Description

[Detailed Description of the Invention] [Industrial Application Fields] The present invention is applicable to the identification of banknotes inserted into automatic teller machines, automatic vending machines, etc., or the identification of paper sheets similar to banknotes. The present invention relates to a paper sheet identification device.

[Prior Art] For example, in automatic teller machines, automatic vending machines, etc., when a banknote is inserted into the banknote input section, the denomination of the banknote (
Processing is performed to determine the authenticity of the banknote (types of banknotes such as 1,000 yen bill, 5,000 yen bill, -10,000 yen hole), or the authenticity of the banknote.

A banknote validating device is used as a device for determining the denomination and authenticity of the banknote.

This banknote identification device detects optical patterns such as reflected light and transmitted light that occur in correspondence with the patterns and shapes of banknotes when the banknotes are not irradiated with light, or is used in banknote printing. Detects a magnetic pattern caused by magnetism that remains in ink, etc., and compares it with a preset standard pattern based on its similarity, or combines this similarity with the detection result of the outer diameter of the banknote. I was conducting a differential diagnosis.

In this case, an LED, a photodiode, a phototransistor, or the like is used as a pattern detection means for detecting the optical pattern, and a magnetic head or the like is used for detecting the magnetic pattern.

Incidentally, the output of these photoelectric conversion elements such as LEDs, photodiodes or phototransistors, or magnetoelectric conversion elements such as magnetic heads changes depending on temperature.

Therefore, in order to prevent this, a temperature correction circuit has conventionally been used to perform these temperature corrections.

FIG. 2 is a block diagram showing a conventional banknote validating device that uses an LED as a photoelectric conversion element and performs temperature correction on the LED.

In FIG. 2, reference numerals 5a, . In this case, the drive circuit 7 is subjected to temperature correction by the correction circuit 7 and drives each of the LEDs. This correction circuit 7 sends an output corresponding to the temperature inside the banknote validating device detected by the temperature sensor 6 to the drive circuit 7, and applies temperature correction to the output.

Moreover, the symbols 5b, -, 5b are the LEDs 5a.

. . , are photodiodes for detecting the light reflected by the banknote from 5a. Incidentally, these photodiodes 5b, . . . , 5b and the LEDs 5a, . The photodiode 5b
, . . , 5b output section is an amplifier circuit 9. . . . is connected to the input section of 9. This amplifier circuit 9. . . , 9 are photocurrents (
The signal corresponding to the banknote pattern) is amplified to a predetermined voltage and the output is sent to the multiplexer 10.

The multiplexer 10 is connected to the amplifier circuit 9. . . . 9, selects one of the signals, and sends it to the analog input section of the A/D converter 11.

The A/D converter 11 is connected to the multiplexer 10.
It inputs the analog signal sent out from the bus, converts it into a digital signal, and sends it out to the data bus DB.

A CPU 12, a read/write memory 13, and a reference value memory 14 are respectively connected to the data bus DB.

The CPU 12 reads the digital signal (pattern signal) sent from the A/D converter 11 and stores it in the read/write memory 13,
This read digital signal is stored in the reference value memory 1.
The banknotes are compared with a reference value (reference pattern signal) stored in the memory card 4 to determine the degree of similarity with the reference value, and the banknotes are discriminated based on the results.

Figure 3 shows the LED used in the above-mentioned bill validator.
5a is a graph showing the temperature characteristics (characteristics when temperature correction is not performed).

In the figure, the vertical axis represents the light output (IO>) of the LED 5a, and the horizontal axis represents the ambient temperature of the LED 5a (temperature inside the bill validator) (T
).

As is clear from this graph, the light output value at temperature T is significantly different from the light output value at temperature T2.

Moreover, FIG. 4 shows an example of reading reflected light (in the case where temperature correction is not performed) in which a banknote is irradiated with light using the LED 5a having the temperature characteristics shown in FIG. 3 and the intensity of the reflected light is observed. This is a graph showing. In addition, in the figure,
The vertical axis represents the reflected light intensity (IR), and the horizontal axis represents the position (X) of the banknote in the scanning direction.

Further, in the figure, a curve a shows an example of reading at temperature T1, and a curve a shows an example of reading at temperature T2.

As is clear from the above graph, even if the same LED 5a is used, the reading values will be significantly different due to different temperatures.

Therefore, as shown in FIG. 2, conventionally, the L
A correction circuit 8 applies temperature correction to the drive circuit 7 that drives the ED 5a, thereby attempting to compensate for the temperature characteristics of the LED 5a.

[Problem to be Solved by the Invention] By the way, the temperature compensation method adopted in the conventional device described above is limited to the temperature compensation of the LED, photodiode, and
For photoelectric conversion elements such as phototransistors, or magnetoelectric conversion elements such as magnetic heads.

It is assumed that there is little variation in temperature characteristics. Therefore, if there are large variations in temperature characteristics among these elements, temperature compensation using this method is no longer effective.

This situation will be explained below.

FIG. 5 is a graph showing an example of the temperature characteristics of LEDs used at the same location in three different bill validators of the same model. Note that the vertical and horizontal axes in this figure are the same as in FIG. 3 above. In addition, in the figure, curves A, B, and C represent LEs used at the same location in each device.
This is a curve showing the temperature characteristics of D, and is expressed as a relative value, with the light output at temperature T0 being 1.

When exhibiting such characteristics, for example, L indicating curve B
When the correction circuit is set to compensate for the temperature characteristics of this LED with ED as a reference, the temperature characteristics of this LED and the other LEDs showing curves A and C are greatly different. Temperature compensation for LEDs showing other curves A and C cannot be performed. That is, FIG. 6 is a graph showing this situation. If temperature correction is applied to the LED showing the temperature characteristic shown by the curve B to make it show the temperature characteristic shown by the curve B1 in this figure, other LEDs is necessarily the curve A1. It exhibits a temperature characteristic indicated by Ct.

L in each banknote validating device with such temperature compensation
When the same banknote is irradiated with light using an ED and the reflected light that changes depending on the shade of the figure or pattern is read, the intensity distribution of the reflected light will be the curves A2 and B2 shown in Figure 7.
, C2.

In other words, as is clear from the above graph, the distribution curve of reflected light intensity for the same figure or pattern on the same banknote differs depending on the device used, and there is a risk that the identification results will differ depending on the device. come.

The above explanation is for the case where temperature compensation is applied to the LED 5a, but other sensors used in this type of banknote validation device,
For example, the same situation applies when temperature compensation is applied to photoelectric elements such as photodiodes and phototransistors, or magnetoelectric conversion elements such as magnetic heads. The same applies to other paper sheet validating devices similar to the banknote validating device.

In this way, with the temperature compensation method adopted in conventional paper sheet identification devices, if there are variations in the photoelectric elements such as LEDs used, or the magnetoelectric elements such as magnetic heads, it is difficult to stably identify paper sheets. There remained an element of anxiety from the perspective of conducting the project.

In addition, this type of paper sheet discrimination device uses the above-mentioned LED
In addition to error factors due to the temperature characteristics of the elements that make up the pattern detection means, there are also error factors due to aging of these elements or dust adhering to these elements. No consideration was given to error factors other than characteristics.

An object of the present invention is to be able to correctly correct even if elements with large variations in temperature characteristics are used as elements constituting the above-mentioned pattern detection means, and at the same time to compensate for other error factors other than temperature characteristics. It is an object of the present invention to provide a paper sheet discrimination device that can also correct changes in characteristics caused by.

[Means for Solving the Problems] In short, the paper sheet discrimination device according to the present invention uses a pattern signal obtained by a pattern detection means for detecting patterns such as patterns and figures on paper sheets, and a pattern signal set in advance. A pattern correction value for each predetermined temperature range is determined for each of the pattern detecting means based on the reference pattern signal obtained by The obtained pattern signal is corrected using the pattern correction value to obtain a corrected pattern signal, and then this corrected pattern signal is compared with the reference pattern signal, and based on the comparison result, the paper sheet to be identified is determined. This makes it possible to correct pattern detection errors caused by temperature characteristics of the pattern detection means and other factors for each pattern detection means, and as a result, the pattern detection means has a large This makes it possible to perform appropriate correction even when there are variations in characteristics, and specifically has the following configurations.

(1) In a paper sheet identification device that detects optical or magnetic characteristics of paper sheets to identify the paper sheets, an optical or magnetic pattern representing the optical or magnetic characteristics of the paper sheets is used. a pattern detection means for obtaining a pattern signal corresponding to the temperature detection means for detecting the temperature within the paper sheet discrimination device; and a temperature detection means for detecting the temperature within the paper sheet discrimination device; a reference pattern signal storage means for storing a reference pattern signal of a paper sheet that has been detected by the optical or magnetic detection means at each temperature; pattern correction value storage means for storing pattern correction values for each temperature set in advance for each of the pattern detection means based on the pattern signal; A pattern correction value at a temperature corresponding to the temperature detected by the temperature detection means is selected from the above, and the selected pattern correction value is used to perform an operation to correct the pattern signal detected by the pattern detection means. a calculating means for obtaining a pattern signal; and a determining means for determining paper sheets by comparing the corrected pattern signal obtained by the calculating means with a reference pattern signal stored in the reference pattern signal storage means. Equipped with a configuration.

(2) In addition to the configuration (1), a counter counts the cumulative number of paper sheets that have been identified so far at the temperature detected by the temperature detection means; After determining the type, the integral value of the pattern signal detected by the pattern detection means and the integral value of the reference pattern signal are determined, and the value of the ratio of these integral values is determined, and the value of this ratio and the value of the counter calculation means for performing a pattern correction value correction calculation in which the cumulative average of the pattern correction values is taken as a new pattern correction value by using the count number of , and the pattern correction values stored in the pattern correction value storage means; Configuration with.

[Function] In the configuration (1), the pattern signal obtained by the pattern detection means includes error factors such as temperature characteristics of the pattern detection means, but this is because the pattern correction value is not used. A corrected pattern signal is obtained by the corrected correction calculation. This correction pattern signal is then compared with the reference pattern signal stored in the reference pattern signal storage means to correctly identify the paper sheet.

In this case, the pattern correction value is set for each individual pattern detection means based on the reference pattern signal, and therefore the correction pattern signal obtained using this pattern correction value is based on the characteristics of each pattern detection means. This is a value that has been corrected accordingly. Therefore, even if there are multiple pattern detection means and their characteristics are significantly different from each other, appropriate corrections will be made for each,
Therefore, even in such a case, the error will not become large.

Further, although the pattern correction value is a correction value classified for each temperature, it is not a correction value only for temperature characteristics, but also changes in characteristics due to not only temperature characteristics but also other factors, such as changes in characteristics of the pattern detection means. Since the correction value includes all changes in sensitivity over time and changes in sensitivity due to foreign matter adhering to the surface of the pattern detection means, it is possible to perform more accurate correction than when only temperature correction is performed. It is possible.

Further, according to the configuration (2), the pattern correction value is a cumulative average, taking into account the characteristics of the pattern detection means at the time of discrimination and the correction values used in previous discriminations. As a result, the corrected value is corrected every time the discrimination is made, and the new corrected value is used in the next discrimination, so there is no risk that the correction value itself becomes inappropriate over time.

Embodiment FIG. 1 is a block diagram showing a bill validating device according to an embodiment of the present invention, and FIG. 8 is a perspective view showing sensor arrangement of the bill validating device shown in FIG. 1. , the banknote validating device shown in these figures has most of its configuration in common with the conventional example shown in FIG. The description will be omitted, and in the following description, the characteristic portions of this embodiment will be mainly described in detail.

In FIG. 8, reference numeral 1 denotes a bill conveying device, and the bill conveying device 1 conveys inserted banknotes 2 in the conveying direction indicated by the arrow in the figure.

A bill detector 3 for detecting whether a bill has been inserted is provided in a bill insertion section of the bill conveying device 1 on the near side in the figure. This banknote detector 3 includes a light source 3a such as an LED,
It consists of a light receiving sensor 3b such as a photodiode that detects the light from the light source 3a by sandwiching the conveyance device 1, and detects when the light from the light source 3a is blocked by the banknote and the amount of light reaching the light sensor 3b is weakened. detects that a banknote has been inserted, and sends the detection signal to the data bus D.
It is sent to B.

A pair of magnetic sensors 4, 4 arranged in a direction perpendicular to the banknote transport direction are provided at a position slightly apart from the banknote detector 3 in the banknote transport direction. These magnetic sensors 4.4 are composed of elements, such as magnetic heads, that detect the magnetic density of the banknote 2 and detect the magnetic pattern of the banknote.

Further, at positions further away from these magnetic sensors 4, 4 in the conveyance direction, there are four reflected light detectors 5. ..., 5
is provided.

These reflected light detectors5. . . , 5 constitutes a pattern detection means for detecting an optical pattern corresponding to the pattern or figure of the banknote, and the LED 5a constitutes a light source that irradiates light toward the transport bag M1, and This L
A pair of photodiodes 5b as light receiving sensors provided at a predetermined interval so as to detect the reflected light generated when the light emitted from the ED 5a is reflected by the banknotes conveyed by the conveyance device 1. It is configured.

Furthermore, the reflected light detector 5. . . , 5 (pattern detection means), there is a reflected light detector 5
A temperature detector 6 (temperature detection means for detecting the temperature inside the banknote validating device) is provided to detect the ambient temperature of the banknote validating device.

Note that this embodiment is an example in which correction is applied only to the reflected light detector 5 in order to make the explanation [41]. However, it goes without saying that the magnetic sensor 4 may also be corrected in substantially the same manner as in this embodiment.

Now, the main differences between this embodiment and the conventional example shown in FIG. 2 are as follows.

First, in the conventional example, the LEDs 5a, . . .

While a correction circuit 8 is connected to the drive circuit 7 that drives the sensor 5a, in this embodiment, instead of the correction circuit 8, the temperature signal detected by the temperature detector 6 is converted into a predetermined analog signal. A temperature detection circuit 16 is used, the output of the temperature detection circuit 16 is connected to the input of an A/D converter 17, and the output of this A/D converter 17 is connected to a data bus DB. The point is that there is.

Second, a nonvolatile memory 15 constituting a new pattern correction value storage means is connected to the data bus DB. This non-volatile memory 15 is previously stored in the LEDs 5a, -=, 5a and the photodiode 5b by a method to be described later.

..., 5b, and a predetermined temperature range (i.e., a temperature range expressed as tJ<t≦tJ+1, where t'' and tJ+1 are preset temperatures, and j = 1.2, 3, . . .)) is stored therein.

Thirdly, the CPU 12 includes, as detailed below,
The data sent from the temperature detection circuit 16 digitized by the A/D converter 17 and the data stored in the nonvolatile memory 15 are taken in and sent from each amplifier circuit 9 to the multiplexer 10 and the A/D.
The difference is that a procedure for correcting each data (pattern signal) of the reflected light intensity of a banknote sent through the converter 11 and other necessary procedures are incorporated.

Fourthly, a counter 30 is connected to the data bus DB for counting the number of passing bills detected by the bill detector 3 based on a command from the CPU 12.

The present embodiment will be described in further detail below, including its operation. In the following description, each operation is performed based on instructions from the CPU 12.

In the banknote validating device of this embodiment, when a banknote is inserted, the denomination of the banknote (type of 1,000 yen bill, 5,000 yen bill, -10,000 yen hole, etc.) and its insertion direction are first determined. The front-back direction of a banknote, or the insertion direction of a banknote determined by the front and back sides of the banknote. ) (hereinafter abbreviated as denomination/direction). Then, the pattern correction value C is corrected to complete one cycle of operation, and each time a banknote is inserted. This cycle is repeated.

FIG. 8 is a flowchart showing the operation for determining the denomination and direction of banknotes in this embodiment.

The operation for determining the denomination and orientation of banknotes will be described in detail below with reference to FIG. 9 and FIGS. 1 and 8.

First, when the bill validating device is set to perform a bill validating operation, the CPU 12 enters the state at the beginning of step 301 in FIG. 3, and immediately proceeds to the next step 302.

In this state, as shown in FIG. 8, when the banknote 2 is transported by the transport device 1 in the direction indicated by the arrow in the figure,
The banknote detector 3 detects a banknote, and this detection signal is CP
Sent to U12. In step 302, the presence or absence of this detection signal is determined. If the detection signal is not received, the process proceeds to the next step 303. On the other hand, if there is no detection signal, the process returns to step 301.

In step 303, the digital value (1) of the temperature at that point sent from the A/D converter 17 is stored in the read/write memory 13. When this step is completed, the process proceeds to the next step 304.

During this time, the banknote 2 is further conveyed, and the reflected light detector 5.・
. . . reaches the part 5 (pattern detection means).

These reflected light detectors5. . . , 5 detect reflected light corresponding to the shading of the figure or pattern of the banknote 2, and send the output to the amplifier circuit 9 . . . . Sends to 9. These amplifier circuits9. ..., 9 is the input reflected light detector 5. . . , 5 is amplified to a predetermined voltage and sent to the multiplexer 10. This multiplexer 10 connects each of the amplifiers 9. . . , cyclically selects the signals sent from 9, multiplexes them in time series, and sends them to the A/D.
It is sent to converter 11. This A/D converter 11 converts the input analog signal into a digital value Dt at a predetermined period.
(Composes a pattern signal. Note that i=1.2.3° . . . , n indicates the sample timing. However, n is the number of samples.) Note that the selection period and the conversion period to digital values are set to appropriate values depending on the conveyance speed of the banknote 2, subsequent calculation ability, and the like.

The step 304 reads this digital value D+ (pattern signal) and sends it to the read/write memory 13 (constituting a pattern signal storage means) via the data bus DB for storage.

FIG. 10 is a diagram showing an example of the data DI stored in the read/write memory 13 in this way, and the curve shown by the solid line a in the figure shows the data D1. In addition, in the figure, the vertical axis d is the size of the data (relative value)
, and the horizontal axis i is the sample timing.

When step 304 is completed, step 305
Proceed to. In this step 305, the non-volatile memory 1
The pattern correction value Cj previously stored in 3 is selected and read out. Next, the process proceeds to step 306, and as shown in equation (1) below, the pattern correction value C4 read out in step 305 is multiplied by the data DI corresponding to the CJ to calculate correction data El. death,
This calculation result is stored in the read/write memory 13.

Ei"D+XCJ (1) An example of the correction data EI stored in this way is shown as a dotted curve in FIG.

When step 306 is completed, step 30
Proceed to step 7. In this step 307, the reference values Rzn, d, which are preset and stored for each denomination and direction, are stored in the reference value memory 14 (reference pattern signal storage means).
> (Constitutes the reference pattern signal. However, k is the denomination,
d indicates the direction), and the squared error ε(k, d) of the correction data EI with respect to this is calculated for each denomination and direction by performing calculations expressed by the following equation (2).

ε. , d, = Sanskrit (Rz<k, a+ E+)'...
(2); Hatake! When step 307 is completed, step 30
Proceed to step 8. In this step 308, the obtained ε(k
, d) that takes the minimum value (denote this as !1ε(k, d)).

When step 308 is completed, step 30
Proceed to step 9. In this step 309, the above-described calculation is performed. 1゜ε
(k, d) and a preset limit value εg. ．． If 1fiε(k, d) < ε, proceed to step 311; otherwise, proceed to step 31
Go to 0.

Step 310 is the step 309 in which the ml. ε(
This is a case where it is determined that k, d) ≥ ε1, and in this case, there is no combination of d for which the squared error ε(k, d) takes a value less than the critical value ε. , a higher-level device (not shown) (for example,
The result is output to a device (such as a device that sorts banknotes by aligning the directions for each denomination), and the process proceeds to step 313, where the series of operations ends.

On the other hand, step 311 is the step 309 described above.
This is a case where it is determined that ε(i, dl < ε, but in this case, ε(k, dl is the preset limit value ε
If there is only one combination of d that takes a value of 1 or less, then the combination of d is determined to be the denomination and direction of the banknote 2, and ε. , d) takes a value less than or equal to the preset limit value ε1, and if there are multiple combinations of d, select the combination of d with the smallest value of the squared error ε(k, d). are determined to be the denomination and direction of the banknote 2, and output the results to a higher-level device (not shown).

When step 311 is completed, step 31
Proceed to step 2. In this step 312, as expressed by the following equation (3), 1 is added to the count number PJ counted in the passed sheet number counter provided for each temperature range stored in the nonvolatile memory 15. The result is stored in the non-volatile memory 15 again, and then the process proceeds to step 313 to end the series of operations.

P t = P j+ 1 (3) When the denomination/direction discrimination operation is completed in this way, the operation of correcting the pattern correction value C is performed next.

FIG. 11 is a flowchart showing the CJ correction calculation operation.

In FIG. 11, when the denomination/direction discrimination operation is completed, the process moves to the initial state of step 501 and immediately proceeds to the next step 502.

In this step 502, the integral value I of the data Ds at the temperature t is determined as expressed by the following equation (4).

■=Exhaust DI...(4) When this step 502 is completed, next step 503
Proceed to. In this step 503, an integral reference value J <*, which is an integral value of the reference value R+<k, d> stored in advance in the reference value memory 14 for each denomination and direction, is determined.
d) from the reference value memory 14 and perform the following (5).
) formula, this J(m, d> and the step 502
Find the ratio K to I obtained in .

K = J <*, d)/I - (5) Note that the above J (k, d) is calculated in advance by the following equation (6) and stored in the reference value memory 14.

J(k, d>=ΣR1(k, d)...(6)llt When step 503 is completed, next step 50
Proceed to step 4. In this step 504, the step 50
Using the value of K obtained in step 3, the count number PJ of the bill passing counter, and the value of C obtained in the previous discrimination operation, calculate K using the following equation (7). By calculating the cumulative average, the corrected value C′ of CI
” and store the result in the nonvolatile memory 15 as a new CI value.

CJ = (CJ X (PJ 1) +K)
/PJ...(7) When this step 504 is completed, the next step 505
Proceed to , and end the CJ correction operation.

Then, when the next banknote is inserted, the denomination/direction discrimination operation is started again, and the same operation as above is performed, and this is repeated every time a banknote is inserted.

In this case, the value of C4 used when a banknote is inserted for the first time is stored in advance in the nonvolatile memory 15 as an initial value. This initial value is, for example, the integral value of data D at each temperature for a banknote of known denomination and direction, and the reference value Rs nc for that denomination and direction.
Calculate the integral reference value J <k, a) by integrating d>, and take the ratio of these as expressed by the following equation (8),
The value of this ratio may be used as the initial value of Cj, or
It may be determined experimentally.

CJ (initial stiffness value> = J <k, d> / r
(8) This initial value is corrected by the correction operation each time a banknote is inserted, and is corrected to a more appropriate value.

According to the embodiment described above in detail, the reflected light detector 5
．． . . , 5 are individually corrected based on the reference value J (+c, d). Therefore, if the reflected light detector 5. Even if the characteristics of .

Furthermore, although the pattern correction value C'' is a correction value classified for each temperature, it is not a correction value only for temperature characteristics, but also changes in characteristics due to not only temperature characteristics but also other factors, such as reflected light detection. Changes in the sensitivity of the detector 5 over time and the reflected light detector 5
Since the correction value includes all changes in sensitivity due to foreign matter adhering to the surfaces of the LED 5a and photodiode 5b that make up the sensor, it is possible to perform more accurate correction than when only temperature correction is performed. It is.

Furthermore, the above-mentioned correction value C' is not fixed, but is calculated for each discrimination by taking the cumulative average by taking into account the characteristics at the time of discrimination and the correction values used in previous discriminations. Since the corrected value is used, the correction value is always correct, and therefore there is no possibility that the correction value itself becomes inappropriate over time.

In the above embodiment, the operation of determining the denomination and direction and the operation of correcting the pattern correction value are all carried out by the CPU 12.
Although the present invention is not limited to this, for example, a part of each of the above operations can be performed by using a multiplication type D/A converter, a digital multiplication circuit, etc. It may also be processed. According to this, it becomes possible to speed up the banknote discrimination process compared to the case where all the operations are performed by the CPU 12.

Further, in the above-mentioned embodiment, an example has been described in which the pattern detection means is corrected when an optical pattern of a banknote is detected by irradiating light onto the banknote and detecting the reflected light. The present invention is not limited to, and can be applied to other optical pattern detection means, such as those using transmitted light, or pattern detection means other than optical pattern detection means, such as magnetic pattern detection means.

Further, in the embodiment described above, the present invention is applied to a banknote validating device, but it can also be applied to a device for validating paper sheets other than banknotes, such as securities.

[Effects of the Invention] As described in detail above, the paper sheet discrimination device according to the present invention basically uses a pattern signal obtained by a pattern detection means for detecting patterns such as patterns and figures on paper sheets;
Based on the preset reference pattern signal,
A pattern correction value for each predetermined temperature range is determined for each of the pattern detection means, and then a pattern signal of the paper sheet to be identified is determined by the pattern detection means, and the obtained pattern signal is subjected to the pattern correction. A device having a configuration in which a corrected pattern signal is obtained by correcting using the value, and then this corrected pattern signal is compared with the reference pattern signal, and the paper sheet to be discriminated is discriminated based on the comparison result. This makes it possible to correct pattern detection errors caused by temperature characteristics of the pattern detection means and other factors for each pattern detection means, and as a result, even if there are large variations in the characteristics of the pattern detection means, appropriate correction can be made. This makes it possible to do the following.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a bill validating device according to an embodiment of the present invention, FIG. 2 is a block diagram showing a conventional bill validating device, and FIG. 3 is a block diagram showing a conventional bill validating device shown in FIG. FIG. 4 is a graph showing the temperature characteristics of the LED 5a used (characteristics without temperature correction), and the reflected light is irradiated onto a banknote using the LED 5a having the temperature characteristics shown in FIG. 3. Graph showing an example of reading the reflected light observed for the intensity (in the case of no temperature correction), 5th
The figure is a graph showing an example of the temperature characteristics of LEDs used at the same location in three different banknote validators of the same model in a conventional banknote validator. A graph showing the situation when temperature compensation is applied as a reference, and FIG. 7 is a graph showing the shape of the same banknote by illuminating the same banknote with light using the LED in each banknote discrimination device that has undergone temperature compensation as shown in FIG. 6. FIG. 8 is a perspective view showing the sensor arrangement of the banknote validating device shown in FIG. 1; FIG. The figure is a flowchart showing the operation for determining the denomination and direction of banknotes in one embodiment shown in FIG. 1, and FIG. 10 shows an example of data Dl stored in the read/write memory 13 in FIG. 11 are flowcharts showing the operation of correcting the pattern correction value CJ. 5... Reflected light detector constituting pattern detection means, 6
．． 16...A temperature sensor and a temperature detection circuit constituting the temperature detection means; 12...A computing device for obtaining a correction pattern signal, a discriminating means for discriminating paper sheets, and a computing means for performing a correction computation of a pattern correction value. Constituent CPU, 14.
. . . Reference value memory constituting the reference pattern signal storage means; 15 . . . Non-volatile memory configuring the pattern correction value storage means; 30 . Agent Toshiaki Suzuki, Ya11. ′,,,,I
Fig. 7 shows the temperature characteristics of the σ1-no LFD. Fig. 4 shows the reflected light intensity distribution after temperature correction. Fig. 7 shows the denomination/direction discrimination operation. ) Figure 9 shows an example of the 7° routine timing readout stage (7) Figure 1o (a-fr) of the correction operation of Cj) Figure 11

Claims (2)

[Claims] (1) In a paper sheet identification device that detects optical or magnetic characteristics of paper sheets to identify the paper sheets, an optical or magnetic pattern representing the optical or magnetic characteristics of the paper sheets is used. a pattern detection means for obtaining a pattern signal corresponding to the temperature detection means for detecting the temperature within the paper sheet discrimination device; and a temperature detection means for detecting the temperature within the paper sheet discrimination device; a reference pattern signal storage means for storing a reference pattern signal of a paper sheet that has been detected by the optical or magnetic detection means at each temperature; pattern correction value storage means for storing pattern correction values for each temperature set in advance for each of the pattern detection means based on the pattern signal; A correction pattern is created by selecting a pattern correction value at a temperature corresponding to the temperature detected by the temperature detection means, and using the selected pattern correction value, performing an operation to correct the pattern signal detected by the pattern detection means. a calculation means for obtaining a signal; and a discrimination means for comparing the corrected pattern signal obtained by the calculation means with a reference pattern signal stored in the reference pattern signal storage means to discriminate paper sheets. A paper sheet identification device characterized by: (2) The paper sheet identification device according to claim (1), further comprising: a counter that counts the cumulative number of paper sheets that have been classified so far at the temperature detected by the temperature detection means; After discriminating paper sheets by the discriminating means, an integral value of the pattern signal detected by the pattern detecting means and an integral value of the reference pattern signal are determined, and a value of the ratio of these integral values is determined; A pattern correction value that uses the value of this ratio, the count number of the counter, and the pattern correction value stored in the pattern correction value storage means to take a cumulative average of the pattern correction values and sets it as a new pattern correction value. What is claimed is: 1. A paper sheet discrimination device characterized by comprising a calculation means for performing a correction calculation.