JP2532631B2 - Shape determination method for paper sheets - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Industrial field of application) The present invention relates to a sheet shape determining apparatus for determining the shape of a bill or the like used in an automatic depositing machine or the like.

(Prior Art) Conventionally, a device for discriminating the shape of a paper sheet has been used in an automatic depositing machine or the like, and in the conventional device, it is obtained by scanning the entire paper sheet with a line sensor. By comparing the area with the area originally possessed by the paper sheet, it is detected whether the corner of the paper sheet is broken or damaged.

However, when the entire paper sheet is scanned by the line sensor, the front and rear edges of the paper sheet may block a part of the scanning line of the line sensor. The scanning signal becomes unstable.

Therefore, for example, the length in the direction orthogonal to the transport direction is 160 m.
When a line sensor scans every 1 mm of a sheet of paper that is conveyed by m, if the front and back of the sheet cannot be detected, even if the sheet has a normal shape, a 160 mm interview (sheet corner Is 18 mm 1
The same area as when it is damaged by 8 mm) is mistakenly determined to be damaged.

For this reason, in the conventional device, it is not possible to discriminate a shape abnormality such as a bent corner of a paper sheet.

(Problems to be Solved by the Invention) The present invention has been made based on the above circumstances, and provides a sheet shape determining apparatus capable of surely determining a shape abnormality such as a corner break of a sheet. Is what you are trying to do.

[Structure of the Invention] (Means and Actions for Solving the Problems) In order to solve the above problems, the present invention provides the above-mentioned structure through a light projecting unit that irradiates the paper sheet with light and a conveyed paper sheet. It has a detecting means which is provided facing the light projecting means and receives the light from the light projecting means, and the paper sheets are sequentially scanned by this detecting means, and the light from the light projecting means is blocked by the paper sheets. In the method for discriminating the diameter of a sheet by discriminating the shape of the sheet, the legitimate length in the direction orthogonal to the conveying direction of the sheet is determined based on the detection signal by the detecting means, and the detecting means The skew angle of the paper sheet is calculated based on the detection signal, and the original nature of the paper sheet on the scanning line separated from the leading end of the paper sheet by the first distance in the transport direction based on the calculated length and skew angle. The position of the side edge that should be Area within the first distance in the transport direction and within the second distance in the direction orthogonal to the transport direction from the calculated position of the side edge where the paper sheet should originally be, the area where the paper sheet exists Is calculated and the shape of the paper sheet is discriminated by comparing the calculated area where the paper sheet exists and the original area of the above range.

(Operation) The original side of the paper sheet on the scanning line that is separated from the leading end of the paper sheet by the first distance in the transport direction based on the legitimate length and skew angle in the direction orthogonal to the paper sheet transport direction. The position of the end portion is calculated, and within the first distance from the leading end portion of the paper sheet in the conveying direction, and the second side in the direction orthogonal to the conveying direction from the calculated position of the side end portion where the paper sheet should originally be. By calculating the area where the paper sheet exists in the range within the distance and comparing it with the original area of this range, it is possible to determine only the corners of the paper sheet.

(Example) Hereinafter, the Example of this invention is described with reference to drawings.

As shown in FIG. 1, the banknote inspection unit 10 is a unit that is incorporated into an automatic depositing machine or the like, and the LED array 11 that irradiates the entire surface of the banknote with light and the LED array 11 form a banknote transport path. A line sensor 12 is provided opposite to each other with the line sensor 12 receiving the light of the LED array 11 interposed therebetween. A lens array 13 that guides the light of the LED array 11 to the line sensor 12 is provided between the line sensor 12 and the LED array 11.

The banknote is nipped by the conveyor belt 14 and conveyed between the LED array 11 and the line sensor 12.

As shown in FIG. 2, the line sensor 12 scans the entire surface of the bill, and when the bill is conveyed, the light of the LED array 11 is blocked and the bill shadow area does not receive the light. Become a signal.

The line sensor 12 has a 256-bit detection element, and scans one line each time a bill is conveyed by 1 mm. The resolution of the line sensor 12 is 1 line / 1 mm.

As shown in FIG. 3, the line sensor 12 is driven by the line sensor processing circuit 15, and the output signal of the line sensor 12 is quantized by the line sensor processing circuit 15 and sent to the microprocessor 16.

The microprocessor 16 determines the shape of the paper sheet based on the scanning signal from the line sensor 12, and the memory
Numeral 17 is adapted to temporarily store the detection data in order to discriminate the shape of the paper sheet.

Further, the memory 18 stores in advance a software program and data for discriminating the shape of paper sheets.

 Next, the operation of the above configuration will be described.

First, the banknote is transported and the LED array 11 and the line sensor 1
When it enters between 2 and 2, the output signal of the line sensor 12 changes, and the tip is first detected as indicated by A1 in FIG.

The microprocessor determines when the signal first changes based on the scanning signal as the leading edge of the bill, and stores the data of the right end and the left end of the bill at this time in the memory.

At the right end and the left end of the banknote, it is determined how many bits the output signal of the line sensor 12 has changed from bright to dark and from dark to bright, and the bit number of the change point is set as shown in FIG. The data is stored in the memory for each scanning line.

Then, every time the bill is conveyed by 1 mm, it is scanned by the line sensor 12, and each scanning signal is sent to the microprocessor to perform the above operation.

Then, when there is no change in the scanning signal and there is no data at the right end and the left end, it is determined that the bill has passed through the line sensor 12, and the determination of the shape is started.

The right end data and the left end data are stored for each scanning line, and the length of the bill in the direct light direction and the conveyance direction is determined.

The microprocessor calculates the length by calculating the difference between the data on the right and left edges and compares the length with the length on the previous scan line and the next scan line.

Then, when the change in the length of three consecutive scanning lines is within 1 mm, the length of the central scanning line is determined to be a valid length, and the length data and the scanning line are the number of times of scanning from the leading edge of the bill. I remember what was.

This determination is performed for each scanning line, and when the determined length has already appeared, the sixth scan is performed by storing the number of scans in the memory area of the corresponding length.
Create a histogram of the length data as shown.

Then, the frequency of the histogram is checked from the one having the largest length, and the length having a frequency of 10 or more is determined as the length of the bill. In addition, the number of scans of the last scan line in which this length is detected is stored as data: P.

Next, the skew angle of the bill is determined to determine the shape.

That is, the 30th bit from the center of the 256-bit line sensor (E1, E2) detects the number of scans at which the leading edge of the bill is detected.

As shown in Fig. 4, when the leading edge is detected at E2 (right 30-bit) at the next scan after the leading edge is detected at E1 (30-bit left), the line sensor conveys the bill by 1 mm. Since it is scanned every time and is scanned at 1 line / mm, it is obtained by the following formula.

Skew angle: = tan-1 (1/60) When the length and skew angle of the bill are obtained, the position B'of the left end of the bill in the P-th scanning described above is obtained as shown in FIG.

Next, the position of C, which is the same position as B'in the scanning direction, is calculated on the line: L 20 mm from the tip A of the bill.

Then, based on the skew angle described above, the correct correct left end position C'on the line L is obtained by C '= C + (P-L) * tan.

Next, a position D of 20 mm is obtained inside the C ', and an area S of the banknote region in the region shown by the diagonal lines outside the C'and D is obtained.

That is, the difference between the position of the left end of each scanning line and the position of D is calculated, and the total sum up to the 20th line is calculated.

20mm in the transport direction from the tip of the bill to the position D
Since the distance between C'and D is 20 mm, the damage amount O is "400-
Area S ”.

As described above, based on the legitimate length and skew angle in the direction orthogonal to the paper sheet conveyance direction and the skew angle, the paper sheet should originally exist on the scanning line that is separated from the leading end of the paper sheet in the conveyance direction by the first distance. The position of the side edge portion is calculated, and within the first distance from the leading end portion of the paper sheet in the transport direction, and from the calculated position of the side edge portion where the paper sheet should originally be, in the direction orthogonal to the transport direction. Two
Since the area where the paper sheet exists in the range within the distance is calculated and compared with the original area of this range, the corner area of the paper sheet with an abnormal shape such as a bent corner is calculated. It can be accurately calculated, and it is possible to reliably determine the abnormality in the shape of the corner portion of the paper sheet, such as the bent corner.

In addition, in the above-mentioned embodiment, only the upper left judgment is explained, but it is needless to say that the corner folding is similarly judged for the three corners of the bill.

Further, the above-described length determination and skew angle determination may be performed during scanning of the line sensor or after the banknote has passed, and the determination timing is not limited.

[Effects of the Invention] As described above, according to the present invention, it is possible to reliably determine a shape abnormality such as a corner break of a paper sheet.

[Brief description of drawings]

FIG. 1 is a perspective view of a paper sheet shape discriminating apparatus of the present invention, and FIG.
FIG. 4 is a plan view for explaining a scanning region of the apparatus shown in FIG. 1, FIG. 3 is an electric block diagram, FIG. 4 is a diagram showing scanning signals of a line sensor, and FIGS. 5 and 6 are data. 7 is a diagram for explaining the memory state of FIG. 7, and FIG. 7 is a diagram for explaining the action of shape discrimination.

Front Page Continuation (72) Inventor Masato Ochikazu 70 Yanagicho, Sachi-ku, Kawasaki City, Kanagawa Prefecture Toshiba Intelligent Technology Co., Ltd. (72) Motota Yamada 70, Yanagicho, Sachi-ku, Kawasaki City, Kanagawa Toshiba Intelligent Technology Corp. (56) References JP 57-142504 (JP, A) JP 58-96205 (JP, A) JP 50-51756 (JP, A) JP 58-96209 (JP, A) Japanese Patent Publication 2-46097 (JP, B2) Actual Public Publication 5-3924 (JP, Y2)

Claims (1)

(57) [Claims] 1. A light projecting means for irradiating a paper sheet with light, and a detecting means provided opposite to the light projecting means via the conveyed paper sheet and receiving light from the light projecting means. In the paper shape determining method, the paper shape is sequentially scanned by the detecting means, and the shape of the paper is determined by blocking the light from the light projecting means by the paper. The proper length of the paper sheet in the conveying direction and the orthogonal direction is determined based on the detection signal of the paper sheet, and the skew angle of the paper sheet is calculated based on the detection signal of the detection unit. The position of the side edge, which should be the original position of the paper sheet, on the scanning line distant from the front end portion of the paper sheet by the first distance is calculated based on Within the distance of and the calculated side edge of the paper sheet should be The area where the paper sheet exists is calculated in a range within a second distance from the position in the direction orthogonal to the transport direction, and the calculated area where the paper sheet exists is compared with the original area of the range. A method for discriminating the shape of a paper sheet, characterized by discriminating the shape of the paper sheet by doing so.