JPS5880777A - Pattern reader for paper sheet - Google Patents

Abstract

PURPOSE:To improve the accuracy of discrimination for the paper sheets, by sampling the reading signal of a sensor corresponding to a track which is decided previously in response to the fact that a part of a pair of sensor trains has detected the edge part of the paper sheet. CONSTITUTION:The clock signal (a) delivered from an oscillator is applied to image sensors 3 and 4 respectively to scan these sensors successively and fed to a counter 6 and the change detecting circuits 10a and 10b respectively. The signal of the sensor 3 is amplified 7a to be sample-held 8a as well as to be fed to a comparator 9a. If the reading signal is larger than the reference signal V, the output signal is sent to the circuit 10a. The circuit 10a detects an edge of a paper sheet 1 and delays 11a the detecting signal to feed it to an A/D converter 12a. The converter 12a is started with the sample pulse of the circuit 8a and converts the reading signal into the digital value to store it in a memory 13. In the same way, the reading signal given from the sensor 4 is also stored in the memory 13.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pattern reading device for paper sheets, which is used in automatic teller machines, etc., and is used to read characters and patterns printed on the surface of paper sheets such as banknotes during the transportation process. The present invention relates to a pattern reading device that reads patterns such as those for processing operations such as authenticity determination.

In automatic teller machines and the like, bills are inserted into an insertion slot so that the longitudinal direction of the bills is horizontal.

6- The inserted banknote is taken inside, and in the process, a specific pattern of 1 to 3000 is read on the banknote, and authenticity is determined based on whether or not the pattern matches a pre-stored pattern. It is done.

FIG. 1 is an illustrative diagram for explaining the principle of a conventional pattern reading device. In the figure, paper sheets 1 are conveyed from conveyor bell 1 to
2 in the X direction. During this conveyance process, the patterns on the symmetrical tracks 1a and Ib of the sheet 1 are read by the photoelectric sensors A and B. The reason for reading the patterns of the symmetrical tracks 1a and 1b in this way is to improve the accuracy of authenticity determination and to reduce the number of model patterns stored in the memory in advance.

That is, when conveying the paper sheet 1, it may be conveyed with its end 1A facing forward, or it may be conveyed with its edge 1B facing forward, or it may be turned over and conveyed with its edge 1A or 1B facing forward. Sometimes it is transported with the front facing up. therefore,
・If you store the model patterns of the symmetrical tracks 1a and lb in advance, you can process the paper sheets 1 by simply changing the order of successive model patterns no matter which direction the paper sheets 1 are conveyed.
This is because you can do ql.

However, when the paper sheet 1 is displaced in the path width direction Y perpendicular to the transport direction X, the track 1a.

1b is shifted from the position of sensors A and B. Therefore, sensors A and B read patterns of other tracks, causing malfunctions in determining authenticity.

In order to prevent such malfunctions, a method may be considered in which all 1-rack patterns included in the displacement width of paper sheet 1 are stored in memory in advance. However, in this method, when a read pattern is compared, if a pattern matches one of a plurality of patterns, the pattern is determined to be true, resulting in a decrease in determination accuracy.

In addition, if the displacement range of the paper sheet 1 is predicted to be large, it is necessary to store patterns of many tracks in the memory, resulting in an undesirably large memory capacity.

Therefore, the main object of the present invention is to provide a paper sheet pattern reading system 4 that can reliably read a predetermined symmetrical track pattern even if the paper sheet is displaced and conveyed. It is to provide.

To summarize this invention, first and second sensor rows are arranged in a direction crossing the conveyance direction of paper sheets, and the first sensor row is connected to one end of the paper sheets and two symmetrical tracks. The second sensor row reads the pattern on the other end of the paper sheet and the other track. Then, the first and second sensor rows are sequentially scanned toward the center of the paper sheet, and when some of the sensors included in the first sensor row detect one end of the paper sheet, one The reading output of the sensors corresponding to rack 1 is sampled, and when some of the sensors included in the second sensor array detect the other end of the paper sheet, all sensors 1 corresponding to the other track are sampled. It is configured to sample the read output of

The present invention will be explained in more detail below along with practical examples shown in the drawings.

Figure 2 and Figures 38 to 3C are 9- FIG. 2 is a diagram for explaining the principle of one embodiment of the present invention.

First, referring to FIG. 2, image sensors 3 and 4 forming first and second sensor arrays are arranged in a direction intersecting the direction in which conveyor belt 2 extends.

As such an image sensor, for example, a CCD type sensor is used. In such image sensors 3 and 4, for example, a light source (not shown) such as a lamp is arranged below the paper sheet 1, and the pattern of the paper sheet 1 is projected by the light from this light source. It is something to detect. The image sensor 3 is configured to read the pattern of the end of the paper sheet 1 in the direction intersecting with the conveying direction is configured to read the pattern of

As shown in FIG. 3A, when the paper sheet 1 is conveyed to the proper position by the conveyor belt 2, the sensor 3a included in the image sensor 3 detects one end of the paper sheet 1, and the sensor 3a
b reads the pattern of track 1a. Further, a 10-sensor 4a included in the image sensor 4 detects the other end of the paper sheet 1, and a sensor 4b reads the pattern of the track 1b. Further, as shown in FIG. 3B, when the paper sheet 1 is displaced in the Y1 direction, the sensor 3C detects one end of the paper sheet 1, and the sensor 3d reads the pattern of the track 1a. Further, the sensor 4c of the image sensor 4 detects the other end of the paper sheet 1, and the sensor 4d reads the pattern of the track 1b. Further, when the paper sheet 1 is displaced in the Y2 direction as shown in FIG. 3C, the V flap 3e detects one end of the paper sheet 1, and the hinge 3f reads the pattern of the track 1a. Further, the sensor 4e detects the other end of the paper sheet 1, and the sensor 4'' reads the pattern of the track 1b.
Even if the paper sheet 1 is displaced in a direction that intersects with the
By reading the patterns with the sensors corresponding to the patterns of tracks 1a and 1b, it is possible to read the patterns of tracks 1a and 1b without fail.

FIG. 4 is a schematic block diagram of an embodiment of the present invention,
FIG. 5 shows change detection circuits 10a and 10b included in FIG.
FIG. 6 is a concrete block diagram of the same (delay circuits 11a, 111), and FIG. 7 is a concrete block diagram of the same link hold circuits 8a, 81+. .

Next, the configuration of an embodiment of the present invention will be described with reference to FIGS. 4 to 7. Oscillator 5 receives clock signal a
The C1 clock signal 1g generation means is configured to generate the clock signal 1g. Clock signal a output from this oscillator 5
is applied to each of the image sensors 3 and 4, and the sensors included in each are sequentially scanned. Furthermore, clock I
i No. a is the counter 6 and change detection circuits 10a and 101)
and are applied to delay circuits 11a and 11b. counter 6
is given a reading command signal. When the counter 6 receives the read command signal, it outputs a start signal synchronized with the clock signal a, and the read signal from the image sensor 3 is outputted to the image sensor 3.4 by the amplifier 7a. , is applied to the sample and hold circuit 8a, and is also applied to the comparison input terminal of the comparator 9a. A reference signal V is applied to the reference input terminal of the comparator 9a. Then, the comparator 9a outputs the read signal and the reference signal @
If the level of the read signal is equal to or higher than the reference signal V, an output j signal is provided to the change detection circuit 10a.

As shown in FIG. 5, the change detection circuit 10a includes a D-type 7'J7101, an EXOR gate 103, an inverter 104, and an AND gate 105. This change detection circuit 10a is connected to the image sensor 3 as shown in FIG. 3A.
It detects one end of the paper sheet 1 based on the read signal, and constitutes a first end detection means. The detection signal of this change detection circuit 10a is given to a delay circuit 11a.

The delay circuit 11a is connected to the inverter 11 as shown in FIG.
1 and a preset counter 112.

This delay circuit 11a delays the detection signal of the change detection circuit 10a by a predetermined period of time. That is, as shown in FIG. 3A, for example, the delay circuit 11a controls the delay time from when the sensor 3a included in the image sensor 3 detects one end of the paper sheet 1 until when the sensor 3b reads the pattern on the track 13-rack 1a. Time the scan time. A delayed output signal 1 of this delay circuit 11a is given to a sample hold circuit 8a and an AD converter 12a.

The sample and hold circuit 8a samples the read output of the image sensor 3 when the delayed output signal, that is, the sample pulse 1 is applied.

The sample hold circuit 8a includes an analog switch 81, a content 1 node 82, and an operational amplifier 83, as shown in FIG.
including. The read signal of the track 1a sampled by the sample and hold circuit 8a is applied to the A-C1 converter 12a. The A/D converter 128 is activated by the sample pulse i and converts the read signal into a digital value and stores it in the memory 13.

In addition, the reading number 4'R of the image sensor 4 is also read in the same way.
The signal is applied to a sample and hold circuit 8b via an amplifier 7b. This read signal is also given to the comparator 9b! ! It is compared with the quasi-signal V, and the other end of the paper sheet 1 is detected 14- by the change detection circuit 10b. The detection signal is then delayed by the delay circuit 11b, and the delayed output is given to the sample and hold circuit 8b and the AD converter 12b. The output signal of the sample and hold circuit 8b is converted into a digital value by the AD converter 12b and stored in the memory 13.

FIGS. 8J and 9 are waveform diagrams of various parts of FIGS. 4 to 7.

Next, the specific operation of one embodiment of the present invention will be described with reference to FIGS. 2 to 9. In the following description, only the image sensor 3 side will be described in order to simplify the description. When the read command signal is applied to the counter 6, the counter 6 generates a start signal @b synchronized with the clock signal @a. When this start signal and the clock signal a are applied to the image sensor 3, the image sensor 3 starts scanning sequentially toward the conveyor belt 2 side.

When the paper sheet 1 is conveyed in the X direction by the conveyor belt 2 and passes the position where the image sensor 3 is arranged, the sensor 3a detects the end of the paper sheet 1 in the example shown in FIG. 3A. Then, as shown in FIG.
The level of read output becomes relatively high. The output signal of this image sensor 3 is amplified by an amplifier 7a, and a comparator 9
8 is compared with the reference signal. When the next sensor is scanned after the sensor 3a is scanned, the output level of the image sensor 3 becomes lower than the reference signal. The output signal d of the comparator 9a is input to the D-type flip 70 tube 101 included in the change detection circuit 10a.

Then, the D-type flip-flop 101 receives the clock signal a.
Based on this, the output of the comparator 9a is stored.

The output signal @e of this D-type flip-flop 101 is stored in the D-type flip-flop 102 by the next clock signal a. Then, E
Exclusive OR is performed with the output signal @r of the 0 tube 102, and samples 1 to 1 to Q are output. This sample goo 1
~Signal g is input to inverter 1 by AND gate 105.
04, and a sample pulse signal 1) is output from the AND gate 105. This sample pulse signal is processed by the delay circuit 11.
is delayed by a predetermined time by a. Then, the delayed signal) is sent to the sample hold circuit 8a and the A-D converter 12a.
given to. The sample hold circuit 8a samples the read output of the image sensor 3 based on the sample pulse i.

That is, the analog switch 81 is controlled by the sample pulse 1, and the analog value of the read signal input during the sampling period, that is, the read signal C of the pattern of the track 1a, is given to the capacitor 82, and the analog hold signal j is outputted via the operational amplifier 83. Output. The level of this analog hold signal j is held until the next sample pulse signal @i is applied to the analog switch 81. Therefore, the analog hold signal @j has a step-like waveform as shown in FIG.

Therefore, this analog hold signal j has a sample pulse signal ik:J! Accordingly, only the pattern data of the track 17-1a to be read is extracted, and this analog hold signal j is converted into a digital signal by the A-D converter 12a activated by the 1 number pulse signal 1, and then stored in the memory 13. is memorized.

On the other hand, in the same manner as described above, the image sensor 4 also detects the other end of the paper M type 1 with the hinge sensor 4a, and the reading signal of the pattern of the track 1b detected by the L sensor 41) is converted into a digital signal (memory 13). It will be stored in C.
11-The data of each pattern of the racks la and 11+ is compared with the data stored in advance, and -[liI false determination of the pattern is performed.

Note that in the case where the paper sheet 1 is displaced in the Y1 direction as shown in FIG. 3B, or in the case where it is displaced in the Y2 direction as shown in FIG. After a predetermined period of time has elapsed since then, the read signal of the scanned sensor is processed as a Zumbling 46, so that it is possible to read the pattern of a particular track la, 'llll.

18- FIGS. 10A to 10C are diagrams for explaining the principle of another embodiment of the present invention. First, with reference to FIG. 10A, four
Two image sensors 20 to 23 are arranged. The image sensor 20 is a first edge detection sensor array and is disposed at a position where one end of the paper sheet 1 passes, and the image sensor 21 is a first track detection sensor array and is disposed at a position where one end of the paper sheet 1 passes. placed in position. Further, the image sensor 22 is a second edge detection sensor array, and the image sensor 22 is a second edge detection sensor array.
The image sensor 23 is placed at a position where the other end passes through.
is the second rack detection sensor array, and the other 1-
It is placed at a position through which the rack 1d passes. Each of the image sensors 20 to 23 is scanned toward the center of the sheet 1 in synchronization with the clock signal. When the sensor 20a included in the image sensor 20 detects one end of the paper sheet 1, a reading signal is output from the sensor 21a of the image sensor 21 scanned in correspondence with the sensor 20a. Also, when the lens 22 a h' included in the image sensor 22 detects the other end of the paper sheet 1, this sensor 4. +228, the sensor 23a of the image sensor 23 scans and outputs a reading number 18. In this way, Sen+U detected the edge of 11 leaves 1.
Scanning sensor 21a corresponding to 20a and 22a,
By outputting a read signal from 23a, the 10th B
As shown in the figure and FIG. 10C, paper sheet 1 is Yl:/
In the case of displacement in the j direction or the Y2 direction, the patterns of tracks 1c and 1d can always be read in b1.

FIG. 11 is a schematic block diagram of another embodiment of the invention. This FIG. 11 is the same as FIG. 4 except for the following points. That is, the image sensors 20 to 23 are given Star 1 to Signal 1 from the counter 6. Then, the read signal of the image sensor 20 is applied to the comparator 9a via the amplifier 7a. Further, a read signal from the image sensor 21 is given to the sample bold 8a via an amplifier 24a. Further, the read signal of the image sensor 22 is given to a comparator 91) via an amplifier 7b. Image sensor 23 read signal +, IAG width gauge 24 . It is applied to the sample hold circuit 81) via the signal line b.

FIGS. 12 and 13 are waveform diagrams of each part of FIG. 11.

Next, the operation of another embodiment of the present invention will be described with reference to FIGS. 10A to 13. In addition, to simplify the explanation, -C is attached to the image sensor 20 and 21 sides.
I will only explain. The image sensors 20 and 21 are given the clock signal @a and the star 1 to signal S, so that
Each is scanned synchronously. Then, as shown in FIG. 10A, a sensor 20a included in the image sensor 20 is
When detecting one end of the paper sheet 1, the detection signal is given to the comparator 9a via the amplifier 7a and compared with the reference signal V. The change detection circuit 10a detects a level change caused by detecting one end of the paper sheet 1 based on the output signal of the comparator 9a, and provides a sample pulse i to the sample hold circuit 8a.

When the sensor 20a included in the image sensor 20 detects one end of the paper sheet 1, the read signal from the sensor 21a of the image sensor 21 being scanned corresponding to the sensor 20a is sent to the sample hold circuit via the amplifier 24a. 8a, the sample hold circuit 8a
samples the read signal. The analog hold signal j sampled by the sample hold circuit 8a is converted into a digital signal by the A/D converter 12a activated by the sample pulse 1, and is stored in the memory 13.

Regarding the image sensors 22 and 23, when the sensor 22a detects the other end of the paper sheet 1 in the same manner as described above, the read signal of the sensor 23a scanned corresponding to this sensor 22a is sent to the sample hold circuit. 8b and analog hold signal j#A-0
The signal is converted into a digital signal by the converter 12b and stored in the memory 13.

Therefore, as shown in FIGS. 108 and 10C, even if the paper sheet 1 is displaced and conveyed, when the image sensors 22 and 20 detect the edge of the paper sheet 1, the edge By reading the output of the sensor included in the image sensor 21 or 23 being scanned corresponding to the sensor that detected the
patterns can be read.

As described above, according to the present invention, a pair of sensor arrays are arranged in a direction intersecting the conveyance direction of paper sheets, and a part of each sensor array detects the edge of the paper sheet in advance. determine 1
Since the reading signals of the sensors corresponding to the two tracks are sampled, even if the paper sheet is displaced in a direction that intersects with the transport direction, it is always possible to
You can read the rack pattern. therefore,
When determining authenticity, it is not necessary to store model patterns of a plurality of tracks in memory in advance, and the memory capacity can be reduced. Furthermore, since the pattern compared with the model pattern stored in the memory is always a specific pattern, the discrimination accuracy can be improved.

[Brief explanation of the drawing]

FIG. 1 is an illustrative diagram of a conventional pattern reading device. Second
3A, 3B, and 3C are diagrams for explaining the principle of an embodiment of the present invention. FIG. 4 is a schematic block diagram of an embodiment of the present invention. Figure 5 is the 4th
FIG. 2 is a specific block diagram of the change detection circuit shown in the figure. FIG. 6 is also a concrete block diagram of the delay circuit. FIG. 7 is a waveform diagram. FIG. 10A, FIG. 10B, and FIG. 10C are diagrams for explaining the principle of another embodiment of the present invention. FIG. 11 is a schematic block diagram of another embodiment of the invention. FIGS. 12 and 13 are waveform diagrams of each part in FIG. 11. In the figure, 1 is paper sheets, 2 is a conveyor belt, 3°4.2
0 to 23 are image sensors, 5 is an oscillator, 8a, 8b
is a sample hold circuit, 9a, 9b are comparators, 11a
, 11114. L delay circuit, 12a. 12b is an A-D converter, and 13 is a memory. Foil 1 sub-OA drawing Atsushi 10B drawing 540- 1st QC drawing

Claims (7)

[Claims] (1) A pattern reading device that includes a conveying means for conveying 1Jt sheets and reads the pattern of two predetermined tracks at symmetrical positions from both ends parallel to the conveyance force 1 of the sheet. a first sensor arranged in a direction intersecting the conveyance direction of the paper sheets, at least a part of which detects one end of the paper sheets and reads a pattern of one of the two predetermined 1-racks; a second column arranged in a direction intersecting the conveyance direction of the first sheet, at least a part of which detects the other end of the sheet and reads the pattern of the other of the two predetermined tracks;
a sensor array, a scanning means for sequentially scanning the first and second sensor arrays toward the center of the paper sheet, and a part of the sensors included in the first sensor array scans one end of the paper sheet. Depending on the detection 1, the predetermined 2
a first sampling command means for instructing sampling of the read output of a sensor corresponding to one of the two tracks; ^1) According to the l? corresponding to the two predetermined tracks? m 2 +y) I) sampling command means for commanding sampling of the read output of the first sensor array; In response to a sampling command being given from the first assembly for sampling the reading output of the corresponding sensor and the second sampling command means, the corresponding sensor array of the second sensor array is A pattern reading device for leaves, comprising a second sampling means for sampling the read output of the sensor. (2) The first and second sensor arrays are each configured to output a read signal of the pattern by being supplied with a pulse signal, and the scanning means generates a clock signal to read the pattern. A paper sheet pattern reading device according to claim 1, which includes a clock signal generating means to be applied to the first and second sensor arrays. (3) The first sampling command hand g port J1 Some sensors included in the first sensor array detect one end of the paper sheet, and from 1 onwards, the scanning means scans the two 1-racks. A sambling command signal is output when the time required to scan the sensor corresponding to one J is elapsed, and the second sampling command means determines that some of the sensors in the second sensor row are in the front gr! A time elapses from when the other end of the composition is detected to when the scanning means scans the area corresponding to the other of the two tracks;
．． :When outputting sampling command signal J, sea urchin I
.: A pattern reading device for paper sheets according to claim 2. (4) The it'll's 1i degree combining command means derives a detection signal in response to any sensor of the first sensor array detecting one end of the paper sheet.
and a first delay means for delaying the sampling of the first end detection means Jj between the predetermined portions, the second sampling command means &3L1 the second sensor. a second end detecting means that detects the other end of the paper sheet in response to detection of the other end of the paper sheet by any sensor 1 in the column υ; and an output of the second end detecting means. and second delay means for delaying the predetermined time by the predetermined time.
Butter of the paper sheets mentioned]/Reading device. (5) The first delay means transmits a number of clock signals corresponding to the predetermined time in response to the output of the first edge detection means described in ^11. The second delay means, including the counting means, is configured such that: 1) the second end 81 of item 11;
The second 61 number of clock credits corresponds to 1.5
The paper sheet pattern reading device according to claim 4, wherein the 81 number means is whitened. (6) The first sensor array includes: a first edge detection sensor array arranged at a position through which one end of the paper sheet passes; and a first end detection sensor array arranged at a position through which one of the two racks passes. a first track detection sensor array, the second sensor array including: a second edge detection sensor array arranged at a position through which the other end of the paper sheet passes; a second track detection sensor arranged at a position where the other track passes;
The first edge detection sensor array, the first track detection sensor array, the second edge detection sensor array, and the second track detection sensor array are located at the center of the paper sheet, respectively. 3. The paper sheet pattern reading device according to claim 2, wherein the paper sheet pattern reading device scans the paper sheet pattern sequentially and synchronously. (7) The first sampling command means is configured to
In response to any sensor 5- of the edge detection sensor array detecting one end of the paper sheet, the first one-rack detection sensor array is scanned in synchronization with the scanning of the sensor. The second sampling command means, in response to any sensor of the second end detection sensor array detecting the other end of the sheet, instructs sampling of the read output of the sensor. The paper sheet pattern reading device according to claim 6, wherein the paper sheet pattern reading device instructs sampling of the readout output of the sensor of the second track detection sensor array being scanned in synchronization with the scanning of the sensor. .