JP3051146B2 - Paper sheet counting device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a sheet counting apparatus, and more particularly to a sheet counting apparatus for non-contact batch counting of bills and the like.

[Conventional technology]

2. Description of the Related Art As devices for counting paper sheets such as bills, the following two types are generally known.

One is that the stacked sheets placed on the sheet placement section called a hopper are fed out one by one by a friction roller, and the passage of the sheets is detected by a photo sensor while being transported to the stacking section. Is counted.

On the other hand, five suction shafts are provided on a rotary disk, and each of the suction shafts is rotated in conjunction with the rotation of the rotary disk, and a part of paper sheets is suction-separated by suction holes of the suction shaft. It counts while doing.

In addition, there is a counting device disclosed in JP-A-1-321593. As shown in FIG. 15, this device presses the vicinity of the end of the stacked sheets with a projection to form a step on each sheet, moves the image pickup unit from bottom to top, and moves the image pickup section. The counting is performed by reading the change in the reflected light at the end.

[Problems to be solved by the invention]

However, the above two general types of counting devices need to separate the whole or a part of the sheets one by one, so that it takes six seconds to count 100 sheets by a friction roller, and the suction shaft Requires 4 seconds, and it is difficult to further reduce the counting time due to the mechanism.

Further, in the apparatus disclosed in the official gazette, it is necessary to move the imaging unit, and therefore, high-speed counting is not possible mechanically.
In addition, in this apparatus, when the edges of the sheets overlap and the change in the reflected light cannot be read, erroneous counting may occur.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and a sheet counting apparatus capable of accurately and collectively counting sheets in a very short time without moving a sheet and a detecting means during counting. The purpose is to provide.

[Means for solving the problem]

The paper sheet counting device according to the present invention is configured such that, for a plurality of paper sheets that are input with their ends aligned, the paper sheets are bent at a substantially right angle or more, and the edges of each paper sheet are shifted in a parallel state. A paper sheet shifting mechanism for shifting the paper sheets so as to generate light, light irradiating means for irradiating light substantially parallel to a surface formed by the paper sheet edge shifted by the paper sheet shifting mechanism, and this light Imaging means for imaging a shadow of a displaced portion generated on adjacent paper sheets by light emitted from the irradiating means; shadow width detecting means for detecting the width of the shadow obtained by the imaging means; The number of paper sheets is calculated from the width of each shadow detected by the width detection means to calculate whether the number of sheets is one or two, and the total number of input paper sheets is calculated. Display means for displaying the number of printed sheets.

(Operation)

When multiple sheets with aligned edges are forcibly shifted by the sheet shifting mechanism and illuminated with parallel light by the irradiating means, shadows are formed on the surface of adjacent sheets due to the thickness of each sheet. it can. Therefore, this shadow is photoelectrically converted by an image sensor,
By performing counting, high-speed counting can be performed without any movement of the mechanism.

〔Example〕

 FIG. 1 is an explanatory diagram showing the counting principle of the present invention.

When the stacked banknotes 1 are forcibly bent in the middle, a deviation occurs at the leading end, and a step occurs between the banknotes. The light emitted from the LED 2 is radiated to the leading end, and the brightness caused by the shadow generated by the step of the bill and the irradiated part without being affected by the step is changed by the lens 3 to the image sensor 4.
Focused on top.

FIG. 2 is a cross-sectional view illustrating the state of formation of a shadow at the leading end of a bill. The bills 1a, 1b, 1c, 1d, 1e are in a state of being shifted from each other, and when a light beam is irradiated substantially parallel to the line connecting the leading edges, it shows that a shadow is formed due to the thickness of the bill. ing.

FIG. 3 is a cross-sectional view for explaining the formation of the shadow in FIG. 2 in more detail, assuming that the tip of the bill having a thickness d is shifted L, and light is incident on the bill surface at an angle θ. If so, the horizontal length l ₁ of the shadow to be formed is l ₁ = d · cotθ
Where the length of the portion without shadow is l ₂ = Ld · cotθ
Becomes

Therefore, when observed with the image pickup device from above in FIG. 3, the shadowed portions are dark, and the non-shaded portions are bright,
Since this is repeated, the number of bills can be counted.

In this case, if the magnification by the lens is k, the number is N, the pitch distance of the image sensor is a, and the number of pixels of the image sensor is n, the image size on the image mentor is k × (l ₁ + l ₂ ) × There is a relationship of N = k × L × N = a × n.

For example, if the contrast ratio = 1, that is, l ₁ = l ₂ = l, the incident angle θ = 45 °, the bill thickness d = 0.1 mm, the number of sheets N = 120, the sensor pitch a = 0.01 mm, the number of pixels n = 1024 bits, then l ₁ = 0.1mm Lens magnification k = 0.43mm Since the entire bill edge face is 2lN = 24mm, the pixel resolution for light and dark is 2lk / a = 8.6. That is, the pixel is 8.6 for a pair of light and dark portions.
As a result, a sufficiently stable measurement can be performed.

FIG. 4 is a block diagram showing the configuration of the paper sheet counting apparatus 100 according to the present invention.

As described with reference to FIG. 1, the light irradiated on the banknote 1 by the optical system 10 including the light source 2 such as an LED and the lens 3 is photoelectrically converted by the image sensor 4. The converted electric signal is subjected to a predetermined counting process described later by the signal processing unit 20, and the counting result is displayed on the display unit 40 by the CPU 30. The signal processing unit 20 performs an appropriate process, and the digital output value is input to the CPU 30. In addition, RAM3
2 and ROM33 are also connected. And the whole is a battery
Driven by 50.

5 and 6 are block diagrams showing a detailed configuration of the signal processing unit 20.

In FIG. 5, after the photoelectric conversion signal generated by the image sensor 4 is amplified by the amplifier 21, the logical output converted by the comparator 23 through the peak hold circuit 22 is I / O.
Output from the circuit 24 is given to the CPU 30.

In FIG. 6, the output of the amplifier is directly connected to the A / D converter 3.
1 and the data is sequentially stored in the RAM 32 by a timing signal from the CPU, and then the processing is performed by software based on the stored data.

The operation in FIGS. 4 and 5 will be described with reference to the flowchart in FIG. 7 and the waveform chart in FIG.

8A is photoelectrically converted by the image sensor 4 and amplified by the amplifier 21 to obtain a waveform as shown in FIG. 8B.

The image sensor output has an envelope waveform as shown in FIG. 8 (c) by passing through the peak hold circuit 22. A predetermined threshold value is given to the comparator 23 for this waveform, comparison is performed, and the width of the shadow portion is detected (S103). The comparison waveform is as shown in FIG. 8 (d). The CPU section 30 obtains the number of sheets by counting the number of ON parts and measuring the length of the shadow part (S103) and displaying the number. A display is performed on the copy (S104). In the example in FIG. 6,
The output of each element of the image sensor is sequentially A / D-converted by a timing signal from the CPU unit 30 and stored in the RAM 32.
The unit 30 reads the output value of the image sensor stored from the RAM 32, and determines the threshold value by looking at the amplitude (S102).
This threshold value can be set in advance, or data can be taken before placing the paper sheet, and the threshold value can be determined from the value. Note that a fixed threshold may be used when the change in brightness is stable, and the threshold may be automatically set when the change is unstable.

Here, the calculation of the number of sheets will be described in detail. The width of the detected shadow is obtained, the width of each sheet is estimated, and the estimated value is compared with the width of each shadow, and there is an overlapped portion. If the number is calculated, the total number is calculated.

FIG. 9 shows waveform processing when a plurality of sheets overlap, and FIG. 9 (a) shows a case where two sheets overlap.
(B) shows a case where three sheets are overlapped, and the state of overlap is correlated with the waveform diagram corresponding to FIG. 8 (c).

If there is an overlap, the length of the shadow portion becomes longer according to the number of overlaps. In FIG. 9 (a), the width of the shadow for one image is t1, whereas in the overlap region of two images, the length of the shadow is t2. Has become. Similarly, in FIG. 9 (b), it is t3 in the portion where three sheets are overlapped.

When the value of t is in the range of 90% to 110% of the estimated value or set value corresponding to one sheet, one sheet, and 180%
When the number is within the range of 220%, two sheets are calculated, and when the number is within the range of 270% to 330%, three sheets are calculated.

If the width of the obtained shadow is not in such a range, an error is displayed and an instruction to reset the bill is issued.

The width of the shadow used when determining the number of sheets can be set as a standard shadow width per sheet and stored in a ROM or the like for use. Further, the comparison data may be set manually. Further, since the thickness varies depending on the circulation degree of the banknote, it is possible to select a standard value of the shadow width separately for "new ticket", "distribution ticket", and "fatigue ticket".

When the standard shadow width value is determined, the width per sheet may be estimated only when the actual shadow width is often different from the standard value. Further, a plurality of standard shadow width values corresponding to the thickness data of foreign banknotes may be stored in the ROM so that any one of them can be selected manually. The standard shadow width value may be read from the ROM.

In order to measure the number of sheets as described above, it is necessary that the edges of the bills are separated one by one and shifted. No.
FIGS. 10 to 14 show a bending mechanism for this purpose. FIG. 10 is a perspective view showing the appearance of a paper sheet counting apparatus 200 according to the present invention, and FIG. 11 is a partially cutaway front view thereof. As shown in these figures, a bill insertion slot 201 for inserting a bill bundle is provided on the upper surface of the counting device 200, and a substantially J-shaped cavity 202 is formed in this insertion slot. By operating the lever 203 provided near the insertion slot 201, the internal mechanism is driven, and the bill is bent following the bent portion of the cavity 202.

As shown in FIG. 11, inside the counting device main body 200, a pressing member 210 is provided so as to be rotatable around a shaft 212, and one end is fixed to a pressing plate 217 located at an insertion opening of the main body. A flexible member 216 such as a leaf spring is provided which is stretched over the rollers 213 and 214 on the pressing member 210 and the other end of which is locked to the pressing member 210 by a tension spring 215. The flexible member 216 pushes an object on the upper surface with a uniform force. That is, when a bill is inserted from the bill insertion slot 201, the state is as shown in FIG. When the lock (not shown) of the holding plate 217 is released, the banknote bundle 1 is pinched and fixed by a spring, and when the lever 203 is pressed down, the pressing member 210 is rotated in conjunction with this, and is stretched on the upper surface thereof. The flexible member 216 pushes the bill to conform to the shape of the cavity of the body. This state is shown in FIG. In this state, the leading ends of the bundled banknotes are appropriately shifted one by one. Note that a position detecting piece 219 is provided at a lower end of the pressing member 210 to detect a predetermined pressing position, and the detecting piece 219 is detected by, for example, a photo interrupter (not shown).

Inside the counting device 200, there are provided an LED 221 for irradiating light to the position of the bill tip and a condenser lens 222 and an image sensor 223 for detecting reflected light from the irradiation position. In order to secure these optical paths,
The flexible member 216 is provided with a slit 218 as shown in FIG.

As described above, the bills are counted based on the brightness information of the bills obtained by the image sensor. Therefore, since the bill and the counting device can perform counting without any movement, the counting of 100 sheets can be completed in a very short time of about 1 second or less. Further, since the movement during the counting is not required, the mechanism is simplified, the cost is reduced, the size is reduced, and the battery can be driven.

The mechanism that causes the tip of the banknote to shift is not limited to such a mechanism, but various types can be used, but a considerably large shift is formed so that a bright part is formed when the shadow of the adjacent banknote is formed. It is necessary to cause

〔The invention's effect〕

As described above in detail with reference to the embodiments, according to the present invention, a sheet is forcibly displaced by bending the sheet at a substantially right angle or more at the end of the sheet, and the parallel light is irradiated. As there is no moving part during counting, the shadow is clearly created by parallel light with a simple mechanism, and even if paper sheets partially overlap, the total number of sheets can be calculated accurately and quickly. It is possible to provide a small and low-cost sheet counting apparatus. In addition, high-speed counting becomes possible.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing the basic principle of the present invention, FIG. 2 is a cross-sectional view of a bill showing a shadow produced by irradiating a bill surface with light, and FIG. 3 is a relation between an irradiation angle and a length of the shadow. FIG. 4 is a block diagram showing the configuration of the paper sheet counting apparatus according to the present invention. FIGS. 5 and 6 are block diagrams showing details of the signal processing unit in FIG. 4, and FIG. Is a flowchart showing details of the counting operation in the present invention, FIG. 8 is an explanatory diagram showing the state of signal processing, FIG. 9 is an explanatory diagram showing processing in the case where bills overlap, FIG. FIG. 11 is a perspective view showing the appearance of such a paper sheet counting machine, FIG. 11 is a partially cutaway cross-sectional view in FIG. 10, and FIGS. 12 and 13 are illustrations showing how paper sheets are bent and displaced. Fig. 14,
The figure is a side view showing a state in which a slit for transmitting light is provided on a flexible member, and FIG. 15 is an explanatory view showing a conventional counting method. DESCRIPTION OF SYMBOLS 1 ... Sheets (banknotes), 2 ... Light-emitting means, 3 ... Lens, 4 ... Image sensors, 10 ... Optical systems, 20 ... Signal processing units, 21 ... Amplifiers, 22 ... Peak hold Circuit, 23
...... Comparator, 24 I / O, 30 CPU, 31 A / D
Converter, 40 display unit, 50 battery, 216 flexible member, 221 LED, 223 image sensor.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G06M ^7/ 00-11/04

Claims (1)

(57) [Claims] 1. A paper sheet having a plurality of paper sheets fed with their ends aligned so that the paper sheets are bent at a substantially right angle or more so that the edges of the paper sheets are parallel to each other and are shifted. A sheet shifting mechanism for shifting the sheet, light irradiating means for irradiating light substantially parallel to a surface formed by the sheet edges shifted by the sheet shifting mechanism, and light emitted from the light irradiating means. Imaging means for imaging a shadow of a displaced portion generated on adjacent paper sheets by light; shadow width detection means for detecting the width of the shadow obtained by the imaging means; and detection by the shadow width detection means Sheet number calculating means for calculating whether the number of sheets is one or two from the width of each shadow, and calculating the total number of inserted sheets; A sheet counting device comprising a display unit for displaying the number of sheets.