DE1499514A1 - Device for the automatic control of new banknotes before they are packed - Google Patents

Description

Applicant: Gualtiero GIORI

NEW REGISTRATION DOCUMENTS

Device for the automatic control of new banknotes before their packaging

The invention relates to a device for automatic Control of new banknotes before they are packed.

Banknotes must be printed after they have been printed and before they are bundled and Packaging must be checked for misprints. Such mistakes close color misprints, soiling, stains and The like and especially also centering errors of the colored print image in relation to the white edge of the note. The banknotes usually leave the press in the form of larger sheets, on which a certain number of banknote printing plates, line- and in rows. Depending on the format of the banknotes Such finished printed sheets, which are then cut up, can contain around 200 - 500 individual banknote prints. ' The banknote prints on each sheet are visually inspected by a person skilled in the art before cutting the sheet color misprints, stains or soiling and the banknote prints with errors for later Exchange of banknotes after cutting the sheet provided with a marking cross. Because centering error are only detectable on the finished cut banknotes or can be caused by cutting the arches,

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must be missing to sort out banknotes with zeroing errors the cut banknotes can also be checked again. Only when this check for misprints has been carried out and all, with Banknotes marked with a cross or incorrectly centered have been removed and replaced with new banknotes in perfect condition are, they are counted, bundled, provided with banderoles, labeled and packaged.

While the cutting of the sheets, the counting of the banknotes as well as the bundling, labeling and packaging operations can be carried out more or less automatically, up to now the checking of the banknotes for misprints, the marking of the misprints and the subsequent replacement of the misprints had to be carried out can be done by hand against new banknotes in perfect condition. These cumbersome and difficult control functions have so far accounted for around 65% of the total production costs of banknotes, whereby checking the banknotes for centering errors is a particularly strenuous and responsible task, since centering errors in the printed image are usually much more difficult to detect than color misprints or scraps. , .

Another disadvantage of the previous! -Handling concerns the off ·? ·. replacement of the detected and marked misprints with new banknotes, which is very unsatisfactory from the point of view of security. When preparing banknotes, it is desirable to have the individual notes under constant control from printing to final packaging and to avoid individual persons being able to intervene in the workflow? One such, undesirable._ An attack is j, but the mentioned Aijs change, the mistake. yon. i ,. . Hand.; ... - · .-. .— :, ■ - .. ;; .. ■ · .-. , --_. _v ·, _. ';. , -; .-. · - .:. _; -. ".. ..-.-.- ^ ότί; · -η: ον ^ c

The invention has the _r task underlying ,, the, above-mentioned parts and the previous control procedure TJnvollkommenheiten

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of banknotes as far as. possible to turn off and one under other devices working with photoelectric detectors • to create, on the one hand, the examiner from the difficult and exhausting visual determination of centering errors, so that the examiner only has to be relatively easy to do must pay attention to recognizable color misprints and soiling, and on the other hand the removal of misprints or their replacement with perfect new banknotes fully automatically allowed to carry out.

There are already devices for automatic authentication of banknotes in vending machines or automatic banknote changers known, in which, inter alia, photoelectric scans to identify certain characteristic color areas or color nuances or to determine characteristic Differences in brightness at certain bank note locations are used, but these are known prior art on the Areas of the automatic authenticity checker no suggestions for an automatic, photoelectric centering control of the To be taken from the printed image relative to the banknote edge, especially since such a centering check is irrelevant for authenticity checkers plays and is not used.

To solve the problem mentioned, the device for automatic Inspecting new banknotes before they are packaged using photoelectric detectors to scan banknote areas characterized by the following devices, which along the transport path of the banknotes between an automatic Cutting device in which the previously under marking of color misprints or soiled notes visually checked, having a certain number of banknote drafts Sheets are cut, and an automatic bundling

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and packaging device are arranged; a magazine receiving the bills leaving the cutting machine; a Counter; a first detector system for scanning the possibly present markings on one and the other banknote side; a second photoelectric detector system for detection of centering errors, each consisting of at least three photodetectors for scanning the top and off at least three detectors for scanning the underside of the banknotes, of which one detector shows the bright banknote edge on one side Banknote side at a reference point and two detectors put the bright note edge on the adjacent banknote side at two scan different reference points, with the brightness reflected when passing the three edge points mentioned serves as the actual value of the corresponding edge width and is electrically compared with a corresponding target value, one of the Detector systems when a marking is scanned and / or when an actual value does not match a corresponding one Target value with a time delay controlled removal device by an error signal for removing the banknotes with misprints from the transport route as well as one also by the false signals time-delayed input device for filling in the by the removal of banknotes created empty spaces with flawless Banknotes.

The device according to the invention thus allows an essential Relief for the experts checking the banknotes, an increase of security, since only those that are still connected in arcs Banknotes, but not the individual ones that have been cut to size Banknotes are accessible to the operating staff, and also an acceleration of the control and exchange functions, what a substantial saving of the previous very high control costs with standing brings.

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Fig. 1 : Fig 2: Fig. 3! Fig. 4:

Further features of the invention emerge from the subclaims.

The invention is based on the drawings of an embodiment, for example explained in more detail. Show it:

a block diagram of the device according to the invention, a schematic plan view of one of the photoelectric detector systems,

a schematic side view of the detector system according to FIG. 2,

a schematic representation of a bank note for illustration the detection of centering errors, and. .

Fig. 5a ^;

up to 5g: the function of the photoelectric. Detector system according to Figures 2 and 3 illustrate graphs showing that of a detector as a function of sampling time. . measured and corresponding to the reflected brightness Show signals.

After the sheet of banknotes »which have a certain number of in. Banknote images arranged in the form of a matrix and with numbering arranged according to a certain system, which have left printing machines and have been stacked, are inspected in sequence by an examiner. The auditor needs to be taken into account only to color · misprints or stained or soiled banknotes to be concentrated s ^ during the centering errors of the printed image in relation to the subsequent setting sen Score edge <can. The identified color or offset misprints are marked by him, for example with a mijb black. Cross drawn across the sheet of music. The so checked for "color - - _: > borrowed misprints or soiling and accordingly .--; .-

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marked sheets are cut into individual pieces in a cutting machine Banknotes cut up and the individual banknotes then, for example in stacks of 1000 notes with consecutive serial numbers, fed to one or more magazines.

In Fig. 1, the unit 1 means such a magazine, as an input station of the control system. From the magazine 1, the stack of banknotes arrives at a first counter 2 through which the banknotes can be chosen a first time under exfoliation. The banknotes of the stack are then withdrawn individually and one after the other placed one after the other in an adjusted position on a conveyor belt or another suitable, continuously moving transport device which one after the other the stations described below happen.

By the first detector sy star 4, which is both the upper and scanning the bottom of each note, it is determined whether the note is provided with the mentioned marking or not. to for this purpose there is at least one detector above and one Detector arranged below the transport device, which scans with certainty at least that area on which the possibly attached mark appears. In order to release the examiner applying the marking, apply the marking a precisely specified. Place the banknote to attach, the first detector system, if necessary using each several detector heads above and below the transport device, be arranged in such a way that the entire width of each bank note is detected by the detector system. This detector system can work optically. or on magnetic or electrical Address the properties of the selected marking color.

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In the case of light-optical scanning, it is expedient to use the value of the brightness of the light beam scanning the bank note reflected by the bank note, so that if the value falls below a certain reflection value as a result of the light-absorbing dark marking, an output signal is emitted by the photodetector in question. This signal is fed to the unit 9, whose function is described below. So that too The underside of the banknotes can be scanned on the transport device, the carrier holding the banknotes must of course be in such a way be designed that a sufficiently large area of the lower Banknote page is freely accessible. For this purpose, the Banknotes either only at the edge, for example due to jamming, held by the transport device, or the conveyor belt has correspondingly large windows through which most of the the back of the banknote is accessible. ^

The banknotes then pass the two light-optical detector systems 5 and 6, which center the print image Check each banknote with regard to the white banknote edge and its function will be explained in detail later with reference to FIGS. 2-5 will. If at least one of the detectors of these detector systems 5 and 6 detects an incorrect centering, then this detector also supplies an output signal to the unit 9.

The banknotes then pass a removal device 7 and then an input device 10. Both mentioned devices 7 and 10 are controlled by the mentioned unit 9, with a time delay with respect to the time of the output signals of the detector systems 4-6, in such a way that one of one of the Detectors of the systems 4, 5 or 6 as a defective bank note is removed from the transport device by a gripper when it passes through the device 7 and fed to a collecting container 8. The empty space created in this way on the transport

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device is then occupied by the input device 10 with a correct, new banknote, which is a special banknote magazine 11 is removed, previously with a bank

• the special series of notes has been filled. After all banknotes have passed of a certain stack by the control system, the number of misprints in the collecting container 8 must be the same

'be the number of banknotes around which the special series of banknotes in magazine 11 was reduced. This subsequent comparison of the banknote numbers in the container 8 and in the magazine 11 represents a simple additional control option.

The checked or, if necessary, exchanged then arrive Bank notes to a second counter 12, as an additional Check an interim count at the beginning, and then in the performance consisting of the units 13-20, in which

the notes are bundled, banded, labeled, again counted and finally finally packed. This automatic Units can be of a known type and should therefore not be described in more detail here. In ce'r unit 13 will be For example, the incoming notes are bundled 100 pieces-wise, whereby sub-bundles of 10 notes can also be provided; in the Unit14 these bundles are provided with a band, which labeled in the unit 15 by printing, so that the

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individual bundles are provided with information, which `` identify the content according to note value and serial number. In the unit 16, a certain number of bundles marked in this way are combined to form a further large bundle which, for example, can comprise ten sub-bundles of 100 banknotes each; this bundle with, for example, 1000 banknotes receives a second banderole which is in turn labeled by the unit 17 so that the content of the large bundle is indicated on the banderole. The unit

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includes a double count of the banknotes of each bundle that for example works in such a way that each bundle is peeled open at two different corners by bending and thereby is counted. The final packaging of the large bundles takes place in the unit 19, preferably in a well-protecting plastic sleeve. The packaged bundles are finally placed in an output magazine 20 saved.

The units denoted by 3 and 21-27 in FIG. 1 symbolize the electrical voltage sources, voltage dividers and, if necessary, amplifiers to feed the counters, detector systems as well as the unit 9 controlling the removal and input device 7 or 10. The counter values can be known per se Way displayed on a control panel and / or to trigger a warning device or to switch off the entire Systems are used when the lack of a banknote or an excess Note is determined by the counters.

The transport speed of the banknotes can, for example are of the order of magnitude of 3 m per second. The whole described Control system is preferably housed in a locked housing, so that the banknotes to any unauthorized person Intervention are withdrawn. All electrical circuits are preferred transistorized, designed in the form of printed circuits and into easily replaceable compact structural units, expediently in slide-in design, summarized. All switches, operating and setting buttons as well as display and warning lamps are located on a central control panel.

With reference to Fig. 2-5, the aforementioned photoelectric Detector system will be explained in more detail, which is the exact centering checks the print image in relation to the edge of the note,

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In Fig. 4, a bank note is shown schematically, in which the bright, generally white edge with 40 and the border of the colored print or print image 41 is denoted by 42. As shown, the boundary 42 needs the colored print not straight and symmetrical to the outer banknote edge run, but can be curvilinear, depending on the motif of the print. Despite this arbitrariness in the form of the colored Banknote imprint, which can change from note type to note type, the exact centering of the colored imprint in each Determine the trap by just three measurements, or in other words, the exact centering of a colored one with any border The printed note is determined by three lengths. These three reference lines are denoted in FIG. 4 by a1, a2 and b. the Lines a1 and a2-determine the width of the light edge of the banknote on one broad side A of the note in two different places, while b is the width of the light edge of the note on one narrow side B of the banknote is defined at a certain point. Any centering error of the imprint 41 makes itself felt in each case noticeable through the change of at least one of the three mentioned reference length measures:

A linear displacement of the imprint 41 in the direction of the arrow F. according to Fig. 4 relative to the outer edge of the note changes the mass a1 and a2 (in the example under consideration also the mass b, what however, this would not be the case if the narrow-sided delimitation of the imprint 41 ran in a straight line and parallel to the outer edge of the note).

A linear displacement of the imprint 41 perpendicular to the arrow F according to FIG. Λ changes the dimension number b in all cases. A linear displacement of the imprint 41 relative to the outer edge of the note in any direction generally changes all three dimensions.

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A tilt or rotation of the imprint 41 relative to the outside The edge of the note also usually changes all three dimensions.

So it is sufficient to use the photoelectric detection system to To determine the width of the light edge of the note in three different places, two of which are on one side of the note and the third position on one of these adjacent note pages can be selected, preferably, as shown in FIG. 4, on the one Broad side A of the note two measuring points and on one narrow side B the one measuring point. The transport movement of the Bank notes on the transport device are directed in the direction of arrow F according to FIG. It must of course be assumed that all banknotes pass the stationary detector systems at a given constant speed and in precisely adjusted and reproducible relative position happen. This is done by appropriate contact edges or other adjusting elements of the transport device achieved.

A detector system consisting of three individual detectors is shown schematically in FIGS. 2 and 3 and is used for scanning one side of the banknote, while a completely analog system is used to scan the other side of the banknote. These two detector systems corresponding to the units 5 and 6 according to FIG. 1. For scanning the masses a1 and a2 (FIG. 4), each is used consisting of a light source and an optical focusing system components 32a and 32b, through which a narrow, parallel to the broad side of a note or perpendicular to the direction of transport the banknote-oriented light line, which is designated in Fig. 4 with the numbers 32a and 32b, on those points is thrown, which the banknotes one after the other along the predetermined Pass reference measuring sections al or ä-2. That of the irradiated area of the banknote or, in the absence of it

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a bank note, light reflected from a dark background is through a gap 35a or 35b of a detector 31a and 31b measured, of which in Fig. 3 only schematically the cell or an electron multiplier 36 and an amplifier 37 are shown. By means of buttons 33a and 34a or 33b and 34b divides the entire optical system 3Za or 32b into two '' precisely adjust mutually perpendicular directions. The third detector unit for scanning the reference measurement length b the narrow side of the bank note comprises the same structural units 31c to 35c as the other detector units. In contrast to the two light bundles 32a and 32b of the first-mentioned two detector units however, the light bundle 32c (FIG. 4) of this third detector unit performs a rapid linear oscillating movement perpendicularly to the direction of transport of the banknotes, the amplitude of which is greater than the reference measurement length b to be determined, in such a way that, on the one hand, this oscillating scanning also results in the area outside of the bank note and on the other hand an area of the colored imprint 41 is covered. The frequency of oscillation of the scanning The light beam is much greater than the transport speed of the bank note, so that, as shown schematically in FIG. 4 by the zigzag line, the entire edge area is swept over many times on the narrow side B of the banknote when passing this detector.

If the bank note according to FIG. 4 with a steady constant transport movement in the direction of arrow F the scanning area of the two co

° bundles of rays 32a and 32b passed, then is in the two

corresponding photoelectric detectors eiii temporal voltage

to course generated, which is shown schematically in Fig. 5a and 5c for the

o Detector 31a or 31b is shown: As long as the front edge A

ο the banknote has not yet reached the scanning beam,

if they are practically absorbed by a dark background, see above that the output voltage V of the detectors is practically zero.

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At the point in time ti, the front edge A of the bank note passes the Scanning area, and as a result of the good reflection of the bundle of rays through the bright edge of the note, the output voltage increases Detectors to a maximum value, which is maintained until the scanning bundle the boundary 42 of the print image Exceed 41. Then the reflected brightness value falls, depending according to the reflectivity of the printed image, practically momentarily to a smaller value, which is a corresponding steep Drop in voltage V of the detectors.

This voltage drop is for the detector 31b at time t2 (Fig. 5c) and al for the detector 31a for later time points t3 (Fig _v 5a) instead of corresponding to the smaller width of the measurement path a2 towards the measurement section according to Fig. 4. The further The course of the output voltage V of the two detectors fluctuates in accordance with the reflectivity of the imprint 42, which generally differs from place to place, and is immaterial for the function of the detector units. Rather, it is crucial that the time interval between ti and t3 or between ti and t2, which is defined by a sharp rise or fall in the detector output voltage V, is an exact and direct measure of the length of the reference measurement sections a1 and a2. For better metrological detection of these time intervals, an electrical differentiation is expediently carried out in such a way that the instantaneous voltage changes in curves 5a and 5c are converted into one positive and one negative pulse, as shown in FIGS. 5b and 5d. The time interval between

° o these impulses is now the measure for the measured reference

co lengths al or a2. These photoelectrically determined time intervals

ο are used as actual values with corresponding specified setpoints

CD ».

O compared, for example, on the control panel of the control

systems can be set using scale buttons, the scales directly are calibrated in millimeters.

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For this purpose, the time intervals ti-t3 or ti-t2 are converted into electrical voltages, the size of which is proportional to the time intervals and the corresponding voltages serving as setpoints are compared. This conversion can take place in a known manner, for example with the aid of the charging or discharging characteristics of capacitors or using sawtooth-shaped voltages. The mentioned setting buttons for the setpoints bind then the taps of potentiometers.

These nominal values of the reference lengths a1 and aZ, as well as the reference length b, are determined beforehand for each banknote type and, as described, serve as the centering reference values. If the measured actual values of the time intervals exceed a certain, predeterminable tolerance range around the target value, then, as already described, an error signal is sent to the control unit 9, which triggers the actuation of the devices 7 and 10 with a corresponding time delay, the time delay of that time corresponds to which the bank note determined to be defective needs to get from the relevant detector into the device 7; or which subsequently requires the space formed by the removal of the faulty note in order to get into the device 10.

To determine the reference distance b through the third detector unit, it is necessary to ensure that the photoelectric Measurement only within a very defined time interval takes place when the reference distance b is in the detector area is located. For this purpose a gate circuit is provided in such a way that

^co that at the relevant time at which the reference route

° b reaches the beam 32c of this detector, a trigger '

pulse is given to this detector, which marks the beginning of the

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Measurement defined. This point in time is denoted by t4 in FIG. 5e. This trigger pulse is expediently by one of the two first-mentioned detector units controlled in such a way that the pulse at time t4 after a precisely predeterminable delay time with respect to the initial pulse ti is sent.

The voltage curve shown in Fig. 5f corresponds to that of the Detector unit 31c during the oscillating scanning of the edge reflected brightness measured on the narrow side B of the banknote. As long as the bundle of rays is outside the banknote edge loses in the dark underground, the output voltage is practically zero; when sweeping over the light edge of the note the output voltage reaches its maximum value and decreases while the print image immediately adjacent to the edge is being swept over to a medium value; when the light beam moves back during the other half cycle of an oscillatory oscillation the light edge of the note is then swept over again, what in turn corresponds to a time interval of maximum voltage, which then drops to zero when the bank note edge faces outwards is exceeded. As a result of the high speed of the oscillating In practice, only a mean reflected brightness is measured while the print image is passing through the scanning movement, see above that the medium-high voltage curve between two maximum Voltage ranges appear practically constant, as shown in Fig. 5f.

cd "

ο The circuit is now made in such a way that only the duration

co of that voltage pulse of maximum magnitude for the measurement

cd becomes effective, which immediately after the appearance of the trigger

ο pulse occurs at time t4. That is in the representation after

Q Fig. Si shows the voltage interval between times t5 and t6.

As in the case of the detectors already described, this voltage interval is determined by differentiating it into a pair of pulses, and although in a first positive pulse at time t5 and a

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subsequent negative pulse converted at time t6 (Fig. 5g), where the distance between the two pulses, again due to an electrical voltage with a time interval proportional to this Shown large, serves as the actual value, which is associated with a corresponding specified and adjustable on the control panel target value compared will. Mind you, only that becomes the actual value measurement Pulse pair t'5 and t6 (Fig. 5g) used, the pulse after the trigger t4 appears and at which the first pulse is the positive one Impulse is. One can easily see that the interval of this pair of pulses is in any case a measure of the width of the The edge of the note at the reference measuring point b is, irrespective of the point at which the voltage curve according to FIG. 5f is the trigger pulse t4 occurs. In fact, those shown in FIG. 5f are step-shaped Individual pulses, each corresponding to a back and forth movement of the scanning beam during an oscillation period, symmetrical, in such a way that the two areas of maximum tension, each corresponding to the width of the light edge of the note, are below one another are the same. ■

Suitable switching measures ensure that the detector output before time t4 and after time t6 is ineffective for the measurement, as are the outputs of the other two detector units 31a and 31b during the sweep of the lower edge of the note according to FIG. 4, the one for the measurement is not recycled. Such electrical circuits for time-selective sampling are known.

Within the scope of the invention it is of course also possible to use the decisive time interval representing the actual value during this a maximum reflected brightness is measured

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other than through differentiation and subsequent transformation of a time interval. into a time-proportional voltage in a manner suitable for a target / actual comparison. For example, you can also use the built-in reflected Use brightness value.

In principle, it is also possible to provide two oscillating scanning detectors for that bank note edge that is in Direction of transport of the banknote is oriented, while only one Detector scans the adjacent edge of the note, which is oriented perpendicular to the direction of transport. If also the one The print image boundary on the bank note deviates sufficiently strongly from a parallel to the outer note edge, then can You may also dispense with the use of an oscillating scanning detector, in which case the third, the detector unit 31c according to FIG. 4 corresponding detector the relevant bright note edge in the longitudinal direction up to the intersection with the print image boundary recorded.

In any case, it is possible by scanning three predetermined ones Reference widths of the bank note edge, as described, to check the exact centering of the bank note. These reference measuring points of the note edge are of course selected at those points that have a particularly striking jump in brightness bam have a transition from the light edge of the note to the dark printed image.

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Claims (6)

H995-H PATKNTAN8FRUECH £ 1. Device for the automatic control of new banknotes before their packaging using photoelectric detectors for scanning banknote areas, characterized by the following devices, the length of the transport path of the banknotes between an automatic cutting device, in which the previously marked by colored misprints or soiled notes visually checked sheets having a certain number of banknote prints are cut, and an automatic bundling and packaging device is arranged: a magazine fl) receiving the banknotes leaving the cutting machine; a counter (2); a first detector system (4) for scanning the possibly present markings on one and the other bank note side; a further photoelectric detection system (6, 5) for detecting centering errors, each consisting of at least three photodetectors (31a, 32a; 31b, 32b; 31c, 32c) for scanning the upper side and at least three detectors for scanning the lower side of the banknotes, of which one detector (31c, 32c) the bright banknote edge on one banknote side (B) at a reference point (b) and two detectors (31a, 32a; 31b, 32b) the bright banknote edge on the adjacent banknote side (A) at two different ones Scan reference points (a1, a2), the brightness reflected when passing through the three mentioned edges serves as the actual value of the corresponding edge width and is electrically compared with a corresponding target value, one of the detector systems when a marking is scanned and / or if an actual value does not match a corresponding setpoint value, a removal device (7) controlled with a time delay by an error signal, e.g. ur distance- > to remove the misprinted banknotes from the transport route so- ' such as an input device (10), also controlled with a time delay by the false signals, for the failure of the empty spaces with faultless banknotes created by the removal of banknotes »\ .'I ir ' 909849 / QÜOQ ' _ßAD ORIGINAL M 2 .. Device according to claim 1, characterized in that the two Photo detectors (31a, 32a; 31b, 32b) perpendicular to the direction of transport of the Banknote oriented edge on one banknote width (A) and the third photodetector (31c, 32c) scan the edge oriented in the transport direction of the banknote on one narrow side (B) of the banknote and this third detector can only be put into operation for a short period of time, during which the mentioned reference measuring point (b) is located within the detector range. . 3. Device according to claim 2, characterized by one of the output voltage of the detectors during the scanning of the reference measuring point applied electrical differentiation circuit for generating a dem sudden increase in brightness corresponding positive impulse (point in time tl, t5) and a negative pulse corresponding to the sudden decrease in brightness (time t2, t3, t6) and a time-to-voltage converter to generate one of the time intervals between a pair of pulses (tl-t2; tl-t3; t5-t6) proportional voltage as actual value, which corresponds to that on the Control panel of the device adjustable setpoint voltage is comparable. 4. Apparatus according to claim 3, characterized in that the Detek-_ gate (31c, 32c), which scans the edge (B) oriented in the transport direction (F) of the banknote, is an oscillating detector, the scanning speed of which is significantly greater than the transport speed of the banknote. 5. Apparatus according to claim 2, 3 or 4, characterized by one of the Beginning of the measurement period of the third detector (31c, 32c) by a pulse (Time t4) determining delay circuit, soft from one of the two detectors mentioned first is controllable when the scanning beam this Detector detects the bright banknote edge of the front banknote edge viewed in the transport direction (A). 909849/0009 H995H 6. Device na clv claim 1, characterized in that said Marking with a magnetic or electrically conductive paint is attached and the first detector system (4) on the magnetic or electrical properties of that color. BAD ORIGINAL 9 0 98A9 / 00 09