JP2908116B2 - Paper sheet thickness inspection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for inspecting the thickness of a thin sheet such as a bill.

2. Description of the Related Art In an automatic machine used for transfer of banknotes at a financial institution such as a bank, the thickness of a inserted banknote is inspected in the inside thereof, and whether or not to accept the inserted banknote is determined from the result of the thickness inspection. .

[0003]

2. Description of the Related Art In FIG. 4, a thickness roller 42 which is vertically displaceable in a posture traversing the conveyance path 40 is provided on a conveyance path 40. 44, respectively.

[0005] As shown in FIG. 5, paper sheets 46 (for example, bills) are conveyed along a conveyance path 40 and are fed to a thickness roller 42.
, The right and left ends of the thickness roller 42 are vertically displaced during this time, and outputs corresponding to those displacements are obtained by the two thickness sensors 44.

FIG. 6 shows an output waveform of a thickness sensor 44 obtained for a sheet 46 that has not been repaired by attaching a tape 48 (see FIG. 5). The output waveform of the sensor 44 is a simple rectangle.

Further, FIG. 7 shows the output waveform of the thickness sensor 44 obtained for the sheet 46 whose right corner of the sheet 46 has been repaired with the tape 48 at the corner in the transport direction. As shown in the drawing, the output of the right thickness sensor 44 increases at the repaired portion of the paper sheet 46.

FIG. 8 shows an output waveform of the sensor 44 obtained from a sheet 46 having a tape 48 attached to the center on the back side and the portion of which is repaired. As shown in FIG. Although the thickness sensor 44 increases at the repaired portion of the leaves 46, the amount of increase is small.

FIG. 9 illustrates a conventional sheet thickness inspection operation. The output of the thickness sensor 44 is compared with a fixed reference value a corresponding to the regular sheet thickness.
When the thickness of the paper sheet 46 is within the error range based on the value a and the thickness increase of the tape affixed portion is equal to or less than a specified amount,
It is determined that the thickness of the paper sheet 46 is normal (determination that the amount of adhered foreign matter is within an allowable range).

[0009]

In FIG. 10, a tape 48 is used.
The correlation between the position where the sheet is attached and the inspection result of the sheet thickness is explained. When the center of the surface of the sheet 46 is repaired with the tape 48 (the center of the sheet 46 is often torn). Does not sufficiently increase the sensor output at the tape restoration portion.

In particular, when the center of the back surface of the paper sheet 46 has been repaired, the increase in the sensor output at the tape repaired portion becomes extremely small. Is incorrectly recognized as acceptable.

In view of the above, a proposal has been made in which more thickness sensors 44 are arranged along the thickness roller 42, and all of the outputs obtained from these thickness sensors 44 are used for determining the thickness inspection.

However, more thickness sensors 44
In this case, it is necessary to change the configuration of the sensor part, which complicates the configuration and increases the manufacturing cost of the device.

The present invention has been made in view of the above-mentioned conventional circumstances, and an object of the present invention is to provide a device capable of sufficiently increasing the recognition rate of foreign substances attached to paper sheets while suppressing an increase in manufacturing cost. Is to provide.

[0014]

In order to achieve the above object, an apparatus according to a first aspect of the present invention is configured as shown in FIG. 1, and the apparatus shown in FIG. A plurality of sensor means 10 arranged to detect the thickness of the paper sheet, and a component included in the output of the sensor means 10 and corresponding to the thickness of the foreign matter attached to the paper sheet, and Sensor output correcting means 12 for increasing the correction according to the correlation characteristic of the above, a thickness comparing means 14 for comparing the corrected sensor output with the stored reference thickness of the sheet, and a reference for comparing with the output of the sensor means 10. A comparison reference storage unit 16 for storing the thickness, a normality determination unit 18 for determining the normality regarding the thickness of the paper sheet from the thickness of the paper sheet indicated by the output of the sensor unit 10 and the result of the thickness comparison, have.

The apparatus according to the second aspect of the present invention is configured as shown in FIG. 2. The apparatus shown in FIG. 2 includes a plurality of devices arranged across the moving path of the paper sheet to detect the thickness of the paper sheet. A thickness sensor means 10, a thickness comparing means 14 for comparing the output of the sensor means 10 with a stored reference thickness of the paper sheet, and a component corresponding to the thickness of the foreign substance attached to the paper sheet, From the comparison reference storage means 20 for storing the thickness of the comparison reference which has been reduced in accordance with the correlation characteristic with the output value of the sensor means, and the thickness of the paper sheet indicated by the output of the sensor means 10 and the result of the thickness comparison. And a normality judging means 18 for judging the normality regarding the thickness of the paper sheet.

Further, an apparatus according to a third aspect of the present invention is configured as shown in FIG. 3. The apparatus shown in FIG. 3 includes a plurality of devices arranged across the moving path of the paper sheet to detect the thickness of the paper sheet. Thickness sensor means 10, thickness comparison means 14 for comparing the output of sensor means 10 with the stored reference thickness, and comparison reference storage means for storing a reference thickness to be compared with the output of sensor means 10. 16 and the characteristic that the component corresponding to the thickness of the foreign matter attached to the paper sheet decreases in accordance with the correlation characteristic between the foreign matter attachment site and the output value of the sensor means.
A comparison reference correcting unit 22 for correcting the comparison reference thickness read out from the control unit 6 and providing the corrected comparison reference thickness to the thickness comparison unit 14;
A normality judging means 18 for judging the normality relating to the thickness of the paper sheet from the thickness of the paper sheet indicated by the output of 0 and the result of the thickness comparison.

[0017]

According to the first aspect of the invention, the thickness of the paper sheet indicated by the output of the sensor means is corrected so as to take into consideration the adhesion of foreign matter (tape), and the corrected thickness is compared with a reference thickness.

Therefore, only the sensor output correcting means 12 is provided, and the conventional sensor means 10 and thickness comparing means 1 are provided.
4. All of the comparison reference storage means 16 and the normality determination means 18 can be used as they are.

In the second invention, the reference thickness for comparison is predetermined in consideration of the attachment of foreign matter (tape), and the detected thickness of the sheet is compared with the reference thickness. .

Therefore, by simply changing the storage contents of the comparison reference storage means 16, all of the other sensor means 10, thickness comparison means 14, and normality judgment means 18 can be used as they are.

Further, in the third invention, the thickness serving as the reference for comparison is corrected to a value taking into account the adhesion of foreign matter (tape),
The corrected thickness is compared with the detected thickness of the paper sheet.
Therefore, only by providing the comparison reference correction means 22, the sensor means 10, the thickness comparison means 14, the comparison reference storage means 1
6. All of the normality determining means 18 can be diverted as it is.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a paper sheet thickness inspection apparatus according to the present invention will be described below with reference to the drawings.

FIG. 11 shows the configuration of the embodiment.
When paper sheets 46 (banknotes and securities) are inserted into this device,
The sheet is conveyed to the sheet detecting section 50 and the insertion of the sheet 46 is detected.

When the paper sheet detecting section 50 notifies the central processing section 52 of the insertion of the paper sheet 46, the central processing section 52 activates the sensor section 54, and the central processing section 24 sends the paper sheet to the sensor section 54. A synchronizing signal for class transport is supplied.

The sensor section 54 includes a pair of thickness sensors 44 and an optical sensor 5 for optically reading a sheet 46.
The output of the thickness sensor 46 and the output of the optical sensor 56 are sampled by using the synchronization signal of the sheet conveyance supplied from the central processing unit 52.

The sampling data obtained by the sensor unit 54 is supplied to an A / D conversion unit 60 via an amplification unit 58.
The data is converted into digital data by the A / D converter 60 and then supplied to the image processor 62.

The image processing unit 62 performs a process of processing the given digital data (for example, a process of rotating paper sheets represented by the image data to a fixed posture), and processes the processed data with a dictionary comparison unit. 64.

The dictionary comparison section 64 includes a dictionary data section 66
The dictionary data is also read from, the read dictionary data and the processed data (the read image of the paper sheet 46 and the digital data indicating the thickness) are compared, and whether or not the inserted paper sheet 46 should be accepted is determined. The inspection result indicating whether or not is written to the storage unit 68.

FIG. 12 illustrates the operation of the present embodiment using a flowchart. As shown in FIG. 13A, a tape 48 is attached to the center of the back surface and the thickness of the repaired paper sheet 46 is detected. Is performed by the thickness sensor 44, and when the output is sampled, the output (thickness output value) of the A / D converter 60 is applied to the coefficient (characteristic of FIG. A large number of pasted paper sheets 46 are prepared, their detected thicknesses are sampled, and the sampling results are statistically processed, which is almost a normal distribution curve.)
Is performed by the image processing unit 62 (see FIG. 12).
Step 1200).

As a result, the component included in the output of the thickness sensor 44 and corresponding to the thickness of the tape 48 attached to the paper sheet 46 is increased as shown in FIG. 13C, and the thickness of the paper sheet 46 is reduced. Is corrected to take account of the adhesion of

When the data (digital data indicating the thickness of the paper sheet 46) is read by the dictionary comparison section 64, the dictionary data (corresponding to the thickness of the regular paper sheet 44) read from the dictionary data section 66 is read. Fixed reference value a) and tape 48
Is compared with the data (digital data indicating the thickness of the paper sheet 46) whose thickness has been corrected (step 1 in FIG. 12).
202).

At this time, the thickness of the paper sheet 46 is equal to the reference value a.
If the increase in the thickness of the tape-attached portion is confirmed to be equal to or less than the specified amount within the error range of (1) (step 1204 in FIG. 12), it is determined that the paper sheet 46 is normal in thickness (foreign matter). Is determined to be within the allowable range (step 1206 in FIG. 12).

When it is confirmed that the thickness of the paper sheet 46 is out of the error range of the reference value a, or that the increase in the thickness of the tape-attached portion is equal to or more than the specified amount (FIG. 1).
Two steps 1208), it is determined that the paper sheet 46 is not regular (step 1210 in FIG. 12).

As described above, according to the present embodiment, the paper sheet 46 with the tape 48 affixed to the center of the back surface is inserted, and the sensor output at the tape affixed portion is moderate as shown in FIG. Even if the number increases, the tape 48 is corrected according to the characteristics shown in FIG. 7B and emphasized as shown in FIG. 7C, so that the tape 48 can be surely confirmed. It becomes possible to increase the recognition rate of the tape 48 (foreign matter) that has been performed.

In addition, the function of correcting the sensor output by storing the characteristics of FIG. 13B in advance is added to the image processing unit 62, and the other parts (the sensor unit 54, the dictionary comparison unit 6
4, the dictionary data section 66, etc.) can be used as it is, and therefore, an increase in manufacturing cost can be suppressed.

However, when it is required to divert the image processing unit 62 as it is, as shown in FIG.
A characteristic obtained by substantially inverting the characteristic of (B) is prepared in the dictionary data section 66 as dictionary data.

FIG. 15 illustrates the operation at this time using a flowchart. The thickness of the paper sheet 46 indicated by the digital data output from the A / D converter 60 is processed by the image processor 62. The data is directly read out into the dictionary comparison unit 64 (step 1500 in FIG. 15) and compared with the dictionary data in the dictionary data unit 66 having the characteristics shown in FIG. 14 (step 1502 in FIG. 15).

It is confirmed that the thickness of the sheet 46 is within the error range of the dictionary data (reference value a) having the characteristics shown in FIG. Then (FIG. 15, step 1504), the paper sheet 46
Is determined to be normal with respect to the thickness (determination that the amount of adhered foreign matter is within an allowable range) (step 1506 in FIG. 15), and the thickness of the paper sheet 46 is outside the error range of the reference value a. Or that the increase in the thickness of the tape-attached portion is equal to or greater than the specified amount (FIG. 1).
5 Step 1508), it is determined that the paper sheet 46 is not regular (step 151 in FIG. 15).
0).

When the dictionary data of the dictionary data section 66 cannot be changed (generally shipped products have difficulty changing the dictionary), the dictionary data is multiplied by a correction value and the dictionary data is converted to the characteristic shown in FIG. Is added to the dictionary comparison unit 64, or a dedicated circuit for performing the processing is provided.

FIG. 16 illustrates the operation at this time using a flowchart. Data indicating the thickness of the paper sheet 46 is read from the image processing section 62 (step 1600 in FIG. 16), and the data is read from the dictionary data section 66. When the dictionary data indicating the thickness reference value a is read (FIG. 16, step 1)
602), the dictionary data is multiplied by the correction value, and the dictionary data is corrected to the characteristics shown in FIG. 14 (step 1 in FIG. 16).
604).

The data indicating the thickness of the paper sheet 46 is compared with the corrected dictionary data (step 1 in FIG. 16).
606), by using this comparison result, it is determined whether or not the inserted paper sheet 46 is normal (FIG. 16).
Steps 1608, 1610, 1612, 161
4).

Incidentally, it is also possible to combine the processing of FIGS. 12, 15 and 16, and in that case, it is preferable that the correction by the coefficient is made as small as possible and that part is covered by the threshold value.

Further, when the number of the thickness sensors 44 is increased, the number of sensors is twice as large as the actual number, so that the recognition rate of the foreign matter (tape 48) is significantly increased.

[0044]

As described above, according to the present invention, a foreign matter adhering to a paper sheet can be reliably detected regardless of its adhering position without increasing the number of sensors for detecting the thickness of the paper sheet. For this reason, it is possible to increase the recognition rate of foreign matter attachment while suppressing an increase in manufacturing cost.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of the first invention.

FIG. 2 is a diagram illustrating the principle of the second invention.

FIG. 3 is a diagram illustrating the principle of the third invention.

FIG. 4 is an explanatory diagram of a device configuration for detecting the thickness of a paper sheet.

FIG. 5 is an explanatory diagram of a detection operation of a thickness of a paper sheet.

FIG. 6 is an explanatory diagram of a waveform of a sensor output obtained for a sheet to which a tape is not attached.

FIG. 7 is an explanatory diagram of a waveform of a sensor output obtained for a sheet on which a tape is stuck on the right side.

FIG. 8 is an explanatory diagram of a waveform of a sensor output obtained for a sheet having a tape adhered to the back side of a central portion.

FIG. 9 is a diagram illustrating the operation of a conventional thickness inspection.

FIG. 10 is a diagram illustrating a correlation between a tape attachment position and an inspection result.

FIG. 11 is a configuration explanatory view of an embodiment.

FIG. 12 is a flowchart illustrating the operation of the embodiment.

FIG. 13 is a flowchart illustrating the operation of the embodiment.

FIG. 14 is an explanatory diagram of characteristics of dictionary data.

FIG. 15 is a flowchart illustrating the operation of the embodiment.

FIG. 16 is a flowchart illustrating the operation of the embodiment.

[Explanation of symbols]

 Reference Signs List 40 conveyance path 42 thickness roller 44 thickness sensor 46 paper sheet 48 tape 50 paper sheet detection section 52 central processing section 54 sensor section 56 optical sensor 58 amplification section 60 A / D conversion section 62 image processing section 64 dictionary comparison section 66 dictionary Data section 68 Storage section

Claims (3)

(57) [Claims] 1. A plurality of sensor means arranged to traverse the paper sheet moving path to detect the thickness of the paper sheet, and correspond to the thickness of a foreign substance contained in an output of the sensor means and attached to the paper sheet. Sensor output correcting means for increasing the component in accordance with the correlation characteristic between the foreign matter attachment site and the output value of the sensor means, thickness comparing means for comparing the corrected sensor output with the stored reference thickness of the paper sheet, Comparison reference storage means for storing a reference thickness to be compared with the output of the sensor means; and normality relating to the thickness of the paper sheet is determined from the thickness of the paper sheet indicated by the output of the sensor means and the result of the thickness comparison. A sheet thickness inspection device, comprising: 2. A plurality of thickness sensor means arranged across the paper sheet movement path for detecting the thickness of the paper sheet, and comparing the output of the sensor means with the stored reference thickness of the paper sheet. Thickness comparing means, and a comparative reference storage for storing a comparative reference thickness having a characteristic that a component corresponding to the thickness of the foreign substance adhered to the paper sheet decreases according to the correlation characteristic between the foreign substance adhering portion and the output value of the sensor means. Means, and normality judging means for judging the normality with respect to the thickness of the paper sheet based on the thickness of the paper sheet indicated by the output of the sensor means and the result of the thickness comparison. Thickness inspection device. 3. A plurality of thickness sensor means arranged to traverse the moving path of the paper sheet and detecting the thickness of the paper sheet, and comparing the output of the sensor means with the stored reference thickness of the paper sheet. Thickness comparison means, comparison reference storage means for storing a reference thickness to be compared with the output of the sensor means, and a component corresponding to the thickness of the foreign matter adhering to the sheet is a portion where the foreign matter adheres and an output value of the sensor means. A comparison reference correction means for correcting the thickness of the comparison reference read from the comparison reference storage means to a characteristic that decreases in accordance with the correlation characteristic of the sheet, and applying the correction reference thickness to the thickness comparison means; And a normality determining means for determining the normality of the thickness of the paper sheet from the result.