Classifications

• • G—PHYSICS
  • G07—CHECKING-DEVICES
  • G07D—HANDLING OF COINS OR VALUABLE PAPERS, e.g. TESTING, SORTING BY DENOMINATIONS, COUNTING, DISPENSING, CHANGING OR DEPOSITING
  • G07D7/00—Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency
  • G07D7/02—Testing electrical properties of the materials thereof
  • G07D7/026—Testing electrical properties of the materials thereof using capacitive sensors
• • G—PHYSICS
  • G07—CHECKING-DEVICES
  • G07D—HANDLING OF COINS OR VALUABLE PAPERS, e.g. TESTING, SORTING BY DENOMINATIONS, COUNTING, DISPENSING, CHANGING OR DEPOSITING
  • G07D7/00—Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency
  • G07D7/06—Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency using wave or particle radiation
  • G07D7/12—Visible light, infrared or ultraviolet radiation

Definitions

• the invention relates to a method and devices for checking security documents according to the preamble of claim 1.
• DE-PS 1223594 describes a device for capacitive scanning of record carriers, in which the scanning capacitors consist of sensor electrodes arranged on both sides of the record carrier web. The scanning security of this device is not given with regard to inserted, pressed or applied electrically conductive strips, tapes or other particles.
• DE-PS 1774290 describes a measuring arrangement for the automatic evaluation of a characteristic feature of a bank note in a device for checking the authenticity of bank notes by means of capacitive coupling of electrodes which are arranged in a grid.
• This known measuring arrangement does not allow an exact determination of the relevant characteristic at the processing speeds required under today's conditions, and even with a slow test method, only the presence of such a characteristic is ascertained and thus does not do justice to the currently known counterfeits using electrically conductive components, for example in bank notes.
• DE-PS 2834287 describes a genuineness test of ferromagnetic security threads in security prints with exposure to a magnetic field. These test methods are too slow and each require an exact positioning of the test object or the test strip.
• DE-PS 2760165 describes a technically complex test device in which the authenticity of banknotes is determined in particular in the second test section by measuring differences in thickness and fluorescence properties. The examination of only these properties no longer corresponds to the status of the false certificates in circulation. Counterfeit money with watermarks and fluorescent paper or paint can no longer be recognized as false with this device.
• reading heads in processing machines described in DE-OS 3236373 and 3236374, which together with markings on security documents form an electrical capacitor and bring about a defined change in the capacitance value by introducing the ferroelectric between the capacitive electrodes of the reading device, are not for high-speed processing machines and not suitable for checking European banknotes currently in circulation.
• a test arrangement according to DE 4103832 is also known, by means of which capacitive and / or electro-optical and / or millimeter-wave sensors are used along a test section Examination are arranged.
• the examination of the dielectric properties of banknotes is the subject of this document.
• a disadvantage of the known measuring arrangements for testing the capacitive properties is that a sufficiently low capacitive resistance is only achieved in the intended low frequency ranges from 10 to 220 kHz and only with very small distances between the electrodes and the metal thread.
• the influence of the dielectric change is still very large in this frequency range, that is to say that a substance with a large dielectric constant leads to an increase in the capacitance and thus to a reduction in the capacitive resistance between the antennas. For example, a damp false certificate would be recognized as genuine.
• these arrangements in particular in the case of machine authenticity checking, have not yet proven successful.
• EP 589 195 A2 describes a method in which an assignment code is obtained for checking the authenticity of test objects via a detection signal obtained by scanning a scanning area with highly permeable magnetic elements with the aid of a device with an excitation coil and sensor coil, and the authenticity when the detection signal and the assignment code match is affirmed.
• This test method can only be used to a limited extent for plastic cards, paper documents containing magnetic or magnetizable particles and only a few non-European banknotes.
• test methods as described in EP 204 574 A2, 553 402 AI and 560 023 AI, in which geometric and / or physical properties of test objects are classified in the comparison method, can only be used for one type of object to be tested, very much complex and have not become established in practice for processing machines because of the high speed required as the only test method for authenticity in one processing step
• the object of the invention is to eliminate the existing disadvantages of the known test arrangements and methods and to propose a method with which a reliable detection of a characteristic test feature is possible, for many types of banknotes and currencies, for example even when moist or deliberately moistened and / or dirty test objects can be used, can differentiate between them, requires little technical effort, the application of which is suitable for retrofitting in processing machines and corresponds to the rapid throughput of test objects in processing machines.
• An electrically conductive security thread or tape or a flat security feature in banknotes and securities is used as a characteristic test feature. Furthermore, it is an object to design a test device for carrying out the method in such a way that it can be connected upstream in order to carry out an authenticity check before sorting according to currencies and types.
• the object of the invention for carrying out the method further consists in the development of a device for checking security documents which, as a security element, has an electrically conductive strip or thread-like strip for testing both continuously electrically conductive strips and strips which have several electrically conductive, but have mutually insulated areas.
• a security document are today's US banknotes which carry electrically conductive but mutually insulated identifiers on their security thread.
• the method according to the invention for checking security documents provides for electrical signals from transmit antennas to be transmitted and amplified via electrically conductive security features to receive antennas, which are then evaluated according to the amplitude and time profile and compared with existing signal profiles. by converting them into waveforms that are easy have comparable parameters.
• a test device is proposed for banknotes, documents, securities and the like with security strips or thread or a flat security feature using the capacitive coupling, which is used in a banknote processing machine, preferably a counting machine, for example. Is used.
• a test sensor system in the area of optical and / or magnetic and / or format sensors is arranged on a housing assembly.
• the machine guides the banknotes and / or securities past the test device.
• the test sensor system consists of several antennas and / or electrodes.
• the antennas and / or electrodes have an areal longitudinal extension transverse to the transport direction of the test objects that even with a defined lateral clearance of the test objects and regardless of whether a test object with the front or rear side facing upwards passes through the test device, in any case the security strip or -sufficiently sweeps the antennas and / or electrodes.
• the antennas and / or electrodes of the test unit correspond to sliding devices, pressure rollers and / or conveyor belts known per se in order to space the documents to be tested during their rapid passage to the antennas and / or to press them against the electrodes.
• One or more antennas and / or electrodes are fed with high and / or low frequency energy and / or with DC voltage, and one or more antennas and / or electrodes absorb part of the radiated energy again via a security strip or thread.
• the applied voltage changes at one or more receiving antennas and / or receiving electrodes.
• test conditions such as speed
• the antennas and / or electrodes supply the evaluation electronics with a voltage.
• the Evaluation electronics supply a slightly comparable voltage depending on the signal form of the received voltage.
• special filters and / or phase comparators can be used.
• the output pulse of the evaluation electronics is independent of the throughput speed
• a category-related (electrically conductive security strip or security thread or any conductive markings) definition of the evaluation electronics additional amplitude limits are set, the course of which is so close to the amplitude deflection of a test signal that the difference between the defined amplitude limit and the largest possible amplitude deflection of all objects to be tested authenticity is determined. This means that counterfeits that have appeared recently and give a signal that is usually used as an evaluator tesignal would be detected, is determined as a forgery of evaluation electronics according to the invention
• a currency-specific definition by means of evaluation electronics according to the invention - for example for all banknotes of individual countries with similar security strips - is achieved according to the invention in that a time limit for the amplitude of the test signal, for example by means of a controller, can be determined for a maintenance that differs from the duration of the amplitude profile of all other currencies
• an additional test is carried out, e.g. by color detection and / or differentiation and / or magnetic and / or format test method.
• the detection signals supplied by light barriers are linked to the signal of the test sensor system according to the invention and become a machine-specific one Output pulse generated
• a modification of the method consists in driving one or more pairs of transmitting antennas out of phase in order to check security documents capacitive coupling between one of the transmitting antennas, an electrically conductive marking on the security strip and the receiving antenna opposite to the transmitting antenna produces a authenticity-determining signal at an input of an amplifier. From a second transmitting antenna, which is driven out of phase with the first, there is no capacitive coupling of the signal to the receiving antenna, since there is no electrically conductive security strip in the effective range. This arrangement already makes it possible to test a continuously electrically conductive strip. Staggered in relation to these antenna pairs are further pairs of transmitting and receiving antennas, the dimensions and spacing of which are matched to electrically conductive markings on the security strip.
• characteristic amplitude and time signals and thus signals that can be evaluated are forwarded from the receiving antennas to an electronic evaluation system.
• a test is thus carried out which is able to recognize several electrically conductive markings which are insulated from one another and to evaluate them accordingly. It is irrelevant whether the insulation between electrically conductive markings is intended, such as. B. with a US banknote or whether the isolation z. B. by breaks in the continuous electrically conductive security strips, z. B. was called for German banknotes.
• a microcontroller can compare the number of these interruptions with stored values.
• the transmitting or receiving antennas are arranged over the entire working width of the processing machine, an authenticity check of the security documents which is neutral in position is possible. It is therefore irrelevant whether a document is fed with the front or back and / or left or right side security strips and / or shifted transversely to the transport direction. This makes it possible to check documents that can differ both in format and in the arrangement of the security strip in relation to the direction of transport.
• a further test sensor system can be arranged upstream and / or downstream in the transport direction of the banknotes linked (double test) without having to change the software for the processing machine in question, for example when retrofitting with a test device according to the method of the invention
• FIG. 5 block diagram of the evaluation circuit in double test
• FIG. 6 section through a schematic representation of a test device
• FIG. 8 block diagram of a test device.
• test unit and its test sensors are connected in a functional unit to evaluation electronics, essentially consisting of an analog / digital converter and controller or integrator 15, trigger 16, controller, mono-flop 17 and / or AND link 18, via shielded lines.
• evaluation electronics essentially consisting of an analog / digital converter and controller or integrator 15, trigger 16, controller, mono-flop 17 and / or AND link 18, via shielded lines.
• a possible evaluation electronics is shown as a block diagram in FIG. 1.
• the reference numerals 12 denote an RF transmitter, 13 the RF receiver, which absorbs the energy radiated by the receiving antenna 9, amplifies it in the selective amplifier 14 as a currency-specific and / or authenticity useful signal, 15 an integrator, 16 a trigger, which in addition to the existing signals which receives the signals of the light barriers 20 which activate the evaluation circuit and outputs them as time-coordinated pulses via the mono-flop 17 as an output signal for test objects which are found to be genuine.
• false signals 26 do not emit any output signals comparable to bank notes found to be genuine.
• FIG. 6 shows a schematic illustration of a test device in section, which is used in a bank note processing machine, preferably a counting machine, according to the method described above.
• the carrier material 6 has cutouts and / or openings 7 for the light transfer from the light barriers 4, 5. These cutouts and / or breakthroughs 7 can be omitted if crystal-clear carrier material 6 is used.
• the test sensor system consists of several strip sensors 8, 9, in this example two, namely a strip sensor 8 as a transmitting antenna and a strip sensor 9 as a receiving antenna.
• the strip sensors 8, 9 have such an areal longitudinal extension transversely to the transport direction of the banknotes 11 that even with a defined lateral clearance of the banknotes 11 and regardless of whether a banknote 11 with the front or back side facing upwards passes through the test device, in any case the Security strips or threads still pass over the strip sensors 8, 9 and are passed underneath them through the test device.
• conveyor belts 10 run at such a distance from the strip sensors 8 and 9 that the bank notes are pressed against the strip sensors 8 and 9 during their rapid passage.
• Light barriers 4, 5 are arranged between the conveyor belts 11 perpendicular to the direction of banknote passage
• the evaluation electronics are also housed in a shielded area of the processing machine, in this exemplary embodiment expediently in the area of the housing in which, for example, the paper thickness adjustment device is arranged
• test device The defined shielding of the test sensors and the evaluation electronics of electrical and electromagnetic fields as well as the arrangement of the test sensors in the area of the light barriers 4, 5 guarantee a high ratio of useful and fault signals and enable them in connection with the forced guidance by the conveyor belt 10 in connection with a defined one Banknote throughput speed, a currency-specific selectivity of the test device
• Another advantage of this test device according to the invention is that, for example, the moisture content and / or degree of soiling of the test objects no longer appear as a source of disturbance a further test sensor system, for example for a magnetic test, as shown in the block diagram in FIG. 5, can be arranged upstream and / or downstream.
• the output signal of this sensor system is combined with the Output signal of the test sensor system according to the invention linked (double test) without having to change the software for the processing machine in question, for example when retrofitting with a test device according to the invention
• the evaluation electronics connected to the test sensors and the light barriers - as shown in FIG. 2 and FIG. 3 - provide a DC voltage that is dependent on the amplitude profile of the received HF voltage. This is illustrated in the figures mentioned, the signals transmitted, shown in the respective curves a
• curve a shows the transmitted signal and curve b the output signal of the evaluation electronics. It corresponds to v, a passage of 500 bank notes per minute and v 2 a throughput of 1800 banknotes per minute.
• Curve b also illustrates how a banknote detection signal supplied by the light barriers is linked to the signal from the test sensor system and generated to form a machine-specific output pulse. This output pulse is independent of the throughput speed, as can be seen in the comparison of curves b in FIG. 2.
• FIG. 3 shows currency-specific acquisition curves when passing banknotes of different currencies.
• Curve a in turn shows the transmitted signal from the test sensor system, while curve b represents the evaluation signal of a selective amplifier, which was additionally coupled to the evaluation electronics in order to enable currency-specific selectivity of the test device without additional sensors.
• DE means German currency, CH Swiss currency, EG Egyptian currencies and CN Chinese yuan from the 1990 series.
• the amplitude profile of the received RF energy which is different from the different type of security strip, is clearly recognizable in the banknotes of different currencies and so on detectable by the evaluation electronics. If processing of the currency-specific signal is necessary, a signal that is additionally processed by the evaluation electronics for currency-specific classification is possible, for example using a controller.
• Fig. 4 shows detection curves of eleven banknotes in a money counter.
• the banknotes with the numbers 21 to 25 and 27 to 31 have been recognized as real banknotes.
• Test object no. 26 is a falsified certificate deliberately inserted for trial purposes. Due to the lack of a security strip or an imitated security strip, no signal was delivered by the test sensor system. In practice, if there is no signal or a signal that is not specific to banknotes, the processing machine is stopped, and the falsified product or the useless note is removed or stored separately by machine.
• this machine-specific output pulse indicates the detection of the respective security strip or thread and is AND-linked to the output signal of that additional test of the processing machine. If one of the two authenticity signals is missing, the machine is stopped and the operator can remove the incorrect or incorrect banknote.
• FIG. 3 Another possible application with a corresponding definition of the evaluation electronics results from the evaluation signals of the selective amplifier, as shown in FIG. 3.
• the amplitude limit A marked in FIG. 3 is exceeded for all currencies to be checked, then those with a speed v 2 are displayed with a real security strip or thread responding to the test sensor system recognized.
• a specific time t- ⁇ is assigned to each currency.
• tf of the German currency should be chosen larger than t 2 of the Swiss franc or tf of the Swiss franc larger than t 3 of the Egyptian currency.
• Processing machines are equipped with a test sensor system 54, as shown in FIG. 7, which consists of several transmitting and receiving antennas, all of which are arranged parallel to one another and orthogonal to the direction of transport, in particular for testing non-continuously electrically conductive security strips of documents
• Banknotes pass through the entire run in a processing machine, for example a banknote counting machine, onto a transport device such that the longest dimension of the security strip or thread in the banknote is approximately parallel to the direction of transport, for example a German banknote with its longest dimension
• the diagonally offset antenna pairs are offset preferably arranged between the transmitting antennas A2, A3 and the receiving antenna AI
• FIG. 8 shows the block diagram of the test device according to the invention with the control of the test sensor system according to FIG. 7. If a document is fed to a processing machine that contains the test device according to the invention, it is activated by light barriers or similar position-determining sensors.
• the frequency generator 41 controls the transmission antenna A2 and via one Phase shifter 42 on the transmission antenna A3.
• the phase-shifted control prevents interference from external energy and falsified products that have no difference in electrical conductivity are recognized.
• the frequencies that the signals of the two generators are chosen so that one frequency is not a multiple of the other or a multiple of the difference between the two in order to prevent signal distortions at the receiving antennas
• a capacitive coupling of the signal from the transmitting antenna A2 to the receiving antenna AI takes place via a continuously electrically conductive security strip, while the signal from the transmitting antenna A3 is not capacit
• the shortest distance between transmitting antenna A2 and receiving antenna AI is less than the longest dimension of the electrically conductive security strip in the smallest document to be checked. If the security strip is not at any time during the test in the range of effect of the transmitting antenna A2 and the receiving antenna AI, the security strip is in the range of action of the transmitting antenna A3 and the receiving antenna AI, so that the other functions are performed analogously to the case mentioned above.
• a signal is then present at the receiving antenna AI, which supplies a signal to the microcontroller 47 by means of a rectifier 45 and selective amplifier 46, which checks the authenticity classification by comparing the signal of the selective amplifier 46 with a signal stored in the microcontroller 47, e.g. B. causes a special threshold.
• the microcontroller 47 classifies the object to be checked as an object with a continuously electrically conductive security thread, ie as genuine for German banknotes. If there are electrically conductive markings in the security strip, which due to their expansion are not detected by the transmitting antenna A2 and the receiving antenna AI, the same can be recognized by the arrangement of the transmitting antennas B2.i and associated receiving antennas Bl.i according to the invention, since their spacing is around are several times smaller than the distance between the transmitting antenna A2 and the receiving antenna AI.
• the distance between the transmitting antenna B2.i and the receiving antenna Bl.i should be selected, for example, 1.3 mm in order to ensure reliable capacitive coupling.
• the security document to be tested is moved at a defined speed in the effective range of the test sensor system of the test device according to the invention.
• the shifted arrangement of the transmitting antennas B2.i and the receiving antennas Bl.i provides tolerance compensation for an orthogonal shift of the banknote in relation to the transport direction of the document.
• Signals generated at the receiving antennas Bl.i are rectified via 48..50 and Selective amplifier 51..53 fed to the microcontroller 47.
• the signals of the selective amplifiers 46, 51..53 arriving at the microcontroller 47 differ in frequency and amplitude characteristics.
• the document can be classified by the microcontroller 47 by frequency comparison and / or threshold value comparison with predetermined values and stored in the microcontroller 47. These values are determined by manual input, programming and / or comparison with values that have been parameterized with a comparison document that has already been classified.
• the microcontroller 47 generates a machine-specific signal which indicates the authenticity of the banknote to be checked. This classification signal of the microcontroller 47 is coupled to relevant display elements and / or to the corresponding interface of the processing machine for further processing.
• test sensor system 54 which is composed of the transmission antennas A2, A3, B2.i and the receiving antennas AI, Bl.i, is integrated into an existing guide device 56.
• the test sensor system 54 is tangential to the guide device 56 or tangential and offset from the transport roller 55 so that it additionally assumes its guiding function in the area of the test sensor system 54. A banknote to be checked therefore comes into the range of action of the sensors without additional pressure means.
• the test sensor system 54 is arranged tangentially to an existing guiding device 56 in such a way that a security document to be tested and driven by transport rollers 55 on the test sensor system 54 is at a defined distance and more defined Speed is passed.
• a defined distance between the transport roller 55 and the guide device 56 or the test sensor system 54 can be set by means of corresponding fastening means on the guide device 56, in particular wobble screws.
• the threshold values and classification variables are parameterized by switches (not shown in the figures) or by appropriate software of the microcontroller 47. As a result, the user is able to change the classification variables by simply switching over in order to check other currencies. In practice, if there is no signal or a signal that is not specific to banknotes, the processing machine is stopped and the false certificate or the useless note is removed.
• the lateral expansion of the antenna arrangement over the entire document width reduces the influence of paper quality, age, moisture, etc. on the authenticity classification.
• This also includes the possibility of classifying, for example, falsified, genuine banknotes and banknotes with a high degree of wear.
• This classification is carried out by appropriate evaluation of the amplitude and time profiles of the signals emitted by the selective amplifiers 46, 51..53 and corresponding threshold value parameterizations by the evaluating microcontroller 47.
• the microcontroller 47 is calibrated manually, software-controlled or by checking special calibration documents, of which the authenticity classification is known. In the latter method, a calibration document is checked by the test device according to the invention as described above. Instead of comparing the signals at the outputs of the selective amplifiers 46, 51..53 with existing signals in the microcontroller 47, these are stored in the microcontroller 47 as reference variables.
• test sensor system 54 can be arranged, for example, at the end of the circular guiding device 56, as shown in FIG. 10 here.
• the necessary pressure devices for the defined spacing and / or touching passing of the test objects past the test device are eliminated This option can be used if the above-mentioned tangentially offset installation of the test sensors 54 in the region of the guide device 56 in the form of a circular arc cannot be implemented.
• pressure means such as springs and pressure rollers are eliminated according to the invention, the test object itself is also subjected to less mechanical stress by the test device.

Priority Applications (18)

Applications Claiming Priority (6)

Publications (1)

Family

ID=27215024

Family Applications (1)

Country Status (22)

Cited By (5)

Families Citing this family (3)

Citations (5)

• 1996
  • 1996-03-29 EP EP96908011A patent/EP0818030B1/de not_active Expired - Lifetime
  • 1996-03-29 KR KR1019970706864A patent/KR100290690B1/ko not_active IP Right Cessation
  • 1996-03-29 DK DK96908011T patent/DK0818030T3/da active
  • 1996-03-29 DE DE19680204T patent/DE19680204D2/de not_active Expired - Lifetime
  • 1996-03-29 UA UA97094792A patent/UA44767C2/uk unknown
  • 1996-03-29 EE EE9700278A patent/EE03322B1/xx not_active IP Right Cessation
  • 1996-03-29 ES ES96908011T patent/ES2122806T3/es not_active Expired - Lifetime
  • 1996-03-29 AU AU51424/96A patent/AU696779B2/en not_active Ceased
  • 1996-03-29 HU HU9800726A patent/HU225082B1/hu not_active IP Right Cessation
  • 1996-03-29 GE GEAP19963893A patent/GEP19991883B/en unknown
  • 1996-03-29 RU RU97116487/09A patent/RU2155989C2/ru not_active IP Right Cessation
  • 1996-03-29 WO PCT/DE1996/000598 patent/WO1996030879A1/de active IP Right Grant
  • 1996-03-29 SK SK1200-97A patent/SK284274B6/sk unknown
  • 1996-03-29 TR TR97/00984T patent/TR199700984T1/xx unknown
  • 1996-03-29 AT AT96908011T patent/ATE170646T1/de not_active IP Right Cessation
  • 1996-03-29 PL PL96322422A patent/PL178898B1/pl not_active IP Right Cessation
  • 1996-03-29 DE DE59600520T patent/DE59600520D1/de not_active Expired - Fee Related
  • 1996-03-29 JP JP52867196A patent/JP3570725B2/ja not_active Expired - Fee Related
  • 1996-03-29 BR BR9607937A patent/BR9607937A/pt not_active IP Right Cessation
  • 1996-03-29 CZ CZ0267097A patent/CZ297280B6/cs not_active IP Right Cessation
  • 1996-03-29 CA CA002216627A patent/CA2216627A1/en not_active Abandoned
  • 1996-03-29 RO RO97-01716A patent/RO117405B1/ro unknown
• 1997
  • 1997-09-26 BG BG101920A patent/BG63353B1/bg unknown

Patent Citations (5)

Also Published As

Similar Documents

Legal Events