EP1439499A1 - Verfahren und Vorrichtung zur Münzerkennung in einer Auswerteeinheit - Google Patents

Verfahren und Vorrichtung zur Münzerkennung in einer Auswerteeinheit Download PDF

Info

Publication number
EP1439499A1
EP1439499A1 EP03001095A EP03001095A EP1439499A1 EP 1439499 A1 EP1439499 A1 EP 1439499A1 EP 03001095 A EP03001095 A EP 03001095A EP 03001095 A EP03001095 A EP 03001095A EP 1439499 A1 EP1439499 A1 EP 1439499A1
Authority
EP
European Patent Office
Prior art keywords
coin
sensor
frequency
runway
coils
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP03001095A
Other languages
English (en)
French (fr)
Inventor
Carlo De Feo
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
IPM International SA
Original Assignee
IPM International SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by IPM International SA filed Critical IPM International SA
Priority to EP03001095A priority Critical patent/EP1439499A1/de
Publication of EP1439499A1 publication Critical patent/EP1439499A1/de
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G07—CHECKING-DEVICES
    • G07D—HANDLING OF COINS OR VALUABLE PAPERS, e.g. TESTING, SORTING BY DENOMINATIONS, COUNTING, DISPENSING, CHANGING OR DEPOSITING
    • G07D5/00—Testing specially adapted to determine the identity or genuineness of coins, e.g. for segregating coins which are unacceptable or alien to a currency

Definitions

  • the present invention relates to a method and a device to recognize coins in a validation unit.
  • a validation unit is a part of a coin-handling device which function is to determine if an inserted coin is acceptable or not.
  • a coin-handling device is an apparatus, which validates and accepts coins used as payment mean usually integrated in a vending machine or a payphone.
  • the coin-handling device comprises a housing equipped with several openings including the coin entry slot, which is accessible from the front panel of the machine.
  • a coin inserted in this slot gets into a runway generally inclined downwards before reaching a specific region or part called validation unit or validator where the coin is analysed according different parameters such as the dimensions and the material.
  • the coin comes through another opening into an escrow and finally in a cashbox (coin accepted), otherwise it is deviated to a coin return receptacle (coin rejected).
  • the invention concerns in particular a coin analysis method carried out by an electromagnetic sensor specially designed for applying this method.
  • the coin passes close by a sensor made of coils mounted in the wall of the runway which impedance is measured by a microprocessor driven unit.
  • the coil impedance is influenced by the nature of the coin metallic alloy and its volume (thickness and diameter). In some devices, the diameter could also be measured with optic cells, which are masked the time of the coin passage.
  • sensors are based on a variable frequency oscillator, which provides a signal through a coil.
  • the presence of the coin changes the signal shape in function of its characteristics. This response could also be collected by another coil coupled to the first one like in a transformer.
  • the response signals are compared to references stored in a non-volatile memory (EPROM, Flash memory).
  • EPROM non-volatile memory
  • Flash memory Flash memory
  • the sensor devices need a high precision mechanical and electronic hardware, which is driven by programs loaded in a non-volatile memory.
  • a coin validation unit has usually to recognize several kinds of coins and to distinguish them from other ones with similar characteristics. For example, a coin of a defined value in a country must not be confused with another coin from another country having very close dimensions and alloy, but with a different value. In order to minimise such errors, the device becomes rather complex and requires high performances.
  • the aim of the present invention is to propose a coin recognition method and device which main features lead to a high reliability, stability, and repeatability with the lowest manufacturing costs.
  • the reliability is defined here as the capacity to have a small failure rate.
  • the stability is the resistance to environmental parameters changes such as temperature, humidity and pressure.
  • the repeatability is the ability to provide results as close as possible on measures made successively on series of same coins.
  • the method is essentially based on calculations made on signal responses received in presence of a coin traversing the area controlled by the sensor.
  • the figure 1 shows the principle of operating of the coin-validating device.
  • a quadratic sinusoidal oscillator QO generates a pair of 90 degrees phase shifted sinusoidal signals V1 and V2 of frequency f.
  • the first signal V1 is applied to the coil of the sensor SE via a power amplifier PA in order to create a current in it.
  • the current-voltage converter IUC converts this current into a voltage V3.
  • the oscillator output signals V1, V2 enter into a comparator CP one after the other through a switch SW to provide a rectangular signal according to the sign of each sinusoidal signal V1 and V2.
  • the converter IUC output V3 is multiplied respectively, through the synchronous detector SD, by each sign signal issued from V1 and V2. Finally, the resulting signal is integrated during the input signal period 1/f providing a number proportional respectively to the conductance g and to the susceptance b of the sensor SE.
  • Both values are directly influenced by the presence of the coin travelling on the runway between the coils of the sensor.
  • Each kind of coin differentiated by the dimensions and the material will provide a specific pair of conductance and susceptance values.
  • the figure 2 shows the different signals at each step of the calculation.
  • the oscillator QO output V1 and V2 have the same frequency f but 90° phase shifted.
  • the rectangular signals SGN(V1) and SGN(V2) are provided by the comparator CP following the switch SW. These signals have fixed positive and negative amplitudes in function of the sign of the input signals V1 and V2.
  • the signal V3 is an image of the current flowing in the coil of the sensor SE. Its phase, relatively to the input signal V1, which is a voltage, depends on the admittance of the sensor in presence of a coin. It is known that a current in an inductance is phase shifted compared to the voltage applied at its ends. The admittance has then the same phase compared to the voltage than the current, according to the Ohm law.
  • This signal is then multiplied once by the sign signal determined by the first input signal V1 and once by the second signal V2 determined by the second signal V2.
  • the value proportional to the sensor conductance g is then calculated by the integrating analog / digital converter ADC providing the average of the produce of V3 by the sign of the input signal V1 (SGN(V1).
  • the value proportional to the sensor susceptance b is calculated with the second input signal V2.
  • the calculation of the sensor admittance Y components (g, b) brings more possibilities to define the admittance than the simple determination of the admittance modulus as it is usually performed in the prior art. In fact, for a same modulus value, there is infinity of pairs of real and imaginary part (g, b) combination.
  • the number of parameters has to be adapted so that the results obtained can be differentiated with the ones of other coins measurements.
  • This is realised by the measuring of the sensor admittance components g and b with several input signal V1, V2 frequencies f1, f2, ... fn.
  • Each coin passing close to the sensor provides a set of conductance and susceptance values (g, b), one pair for each frequency.
  • These values (g, b) are stored in a memory and compared with a reference table or with a reference diagram showing each value of the sensor admittance components g and b in function of the frequency.
  • the calculation circuitry needs n quadratic oscillators, 2n comparators CD, 2n synchronous detectors SD and 2n integrating analog digital converters ADC.
  • the integration period is one quarter of the period of maximum frequency and the integration is made on the signals that is the response to the sum of input frequency
  • the combination of the integration's results allows the separation of the different frequencies contribution. This is due when contributions of a frequency are summed for a time equal or multiple of its period, the result is equal to 0.
  • the summing of the first 8 integrations results with its sign will eliminate frequency f3 and f4 and remain only contributions of frequency f1 and f2; in the same way it is possible to eliminate contributions of f2 and then obtain only f1 response.
  • the first value f1 (minimum value) is determined by appropriate response of the sensor during the coin passage; maximum value is determined on the circuit accuracy, i.e. Analog / Digital converter (ADC) speed.
  • ADC Analog / Digital converter
  • the amplitude of the oscillators output signal varies in function of each frequency because the current flowing in a coil decreases when the frequency increase.
  • the oscillator signals are generated with an amplitude proportional to the frequency, according to f ⁇ where ⁇ is a parameter depending on the sensor design.
  • the present invention relates also to a coin validation device comprising a coin runway, at least one sensor constituted by two symmetrical halves forming a support disposed on each lateral side of the coin runway, a coil is mounted on each said half in the way that one is facing the other and let a gap between the coils faces having a width allowing the passage of a maximum thickness coin, calculation electronic circuitry characterized in that
  • the sensor constitutes the heart of the validator that is specially designed to recognize coins according to above described method.
  • the figure 4 shows an exploded view of a coin validation device or coin validator comprising two sensors placed one beside the other. Each sensor is made by two symmetric support halves (3a, 3a', 3b, 3b'), carrying each one a coil, and mounted on the right and left lateral side of the coin runway (1).
  • the validator is disposed vertically inside the host automate. Left (L) and right (R) sides are defined here as viewed from the front part of the validator near the coin input.
  • the coins enter into the runway (1) through a slot on the topside (coin input Cl) of the validator and leave the validator through another slot at its rear side (coin output CO).
  • the validator is constituted mainly by a right chassis (5) supporting the coin runway (1) and the right sensor halves (not visible on the figure), a left chassis (4) mounted above the coin runway (1) supporting the left sensor halves (3a, 3b).
  • the sensor area of the left chassis (4) is protected by a cover (6).
  • the figure 5 represents the right chassis (5) alone comprising the coins runway (1). On both edges of the runway, openings (7a, 7b) are provided for the junction of the right and left halves of each sensor.
  • Figure 6 shows the right chassis (5) with the sensors mounted in position.
  • the coil (2a, 2b) is mounted on each support half (3a, 3b) in the way that a coil is facing the other mounted on the other half of the sensor located behind the runway wall.
  • the coin passes on the runway through a gap between the two coils having a width allowing the passage of the maximum thickness coins.
  • Both support halves of each sensor thus assembled form a closed magnetic circuit surrounding the runway.
  • the material used for these coil supports is in general ferrite.
  • Figure 7 shows the right sensor halves (3a', 3b') alone with the coil (2a', 2b') formed by an ovoid shaped kernel where the larger part is directed to the bottom edge of the runway. This specific shape is adapted to the diameter range of the coins to be validated.
  • Figure 8 shows a printed circuit board (8) supporting the two complete sensors. This board is placed behind the runway wall of the right chassis (5) so that the runway (1) passes at the level of the junction of each sensor support halves (3a, 3a', 3b, 3b').
  • FIG 9 shows the left chassis (4) with the mounted left sensor halves (3a, 3b).
  • This chassis (4) forms the left wall of the runway and supports the left halves (3a, 3b) of each sensor by maintaining them facing respectively each corresponding right half (3a', 3b').
  • the two coils of one sensor are connected in serial mode, i.e. one end of the first coil is connected to one end of the second coil.
  • the two other ends are connected to the measuring circuitry in order to be supplied by the signals coming from the oscillator as described above.
  • the two sensors are connected in a balanced or differential mode.
  • the aim of such configuration is to compensate the output signal measurement errors due to environmental parameters changes as temperature or electronic component ageing.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Testing Of Coins (AREA)
EP03001095A 2003-01-20 2003-01-20 Verfahren und Vorrichtung zur Münzerkennung in einer Auswerteeinheit Withdrawn EP1439499A1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP03001095A EP1439499A1 (de) 2003-01-20 2003-01-20 Verfahren und Vorrichtung zur Münzerkennung in einer Auswerteeinheit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP03001095A EP1439499A1 (de) 2003-01-20 2003-01-20 Verfahren und Vorrichtung zur Münzerkennung in einer Auswerteeinheit

Publications (1)

Publication Number Publication Date
EP1439499A1 true EP1439499A1 (de) 2004-07-21

Family

ID=32524161

Family Applications (1)

Application Number Title Priority Date Filing Date
EP03001095A Withdrawn EP1439499A1 (de) 2003-01-20 2003-01-20 Verfahren und Vorrichtung zur Münzerkennung in einer Auswerteeinheit

Country Status (1)

Country Link
EP (1) EP1439499A1 (de)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5384453A (en) * 1976-12-29 1978-07-25 Fujitsu Ltd High-speed current-voltage converter
EP0392110A2 (de) * 1989-04-10 1990-10-17 Kabushiki Kaisha Nippon Conlux Münzauswähler
US5199545A (en) * 1991-02-28 1993-04-06 Takamisawa Cybernetics Co., Ltd. Metal body discriminating apparatus
DE10049390A1 (de) * 1999-10-06 2001-04-12 Nippon Conlux Co Ltd Münzinspektionsverfahren und -vorrichtung
EP1172772A2 (de) * 2000-06-30 2002-01-16 Azkoyen Medios de Pago, S.A. Verfahren und Einrichtung zum Feststellen von physikalischen Münzeigenschaften für ihre Identifikation
US6340082B1 (en) * 1999-10-22 2002-01-22 Japan Tobacco Inc. Coin discriminating apparatus

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5384453A (en) * 1976-12-29 1978-07-25 Fujitsu Ltd High-speed current-voltage converter
EP0392110A2 (de) * 1989-04-10 1990-10-17 Kabushiki Kaisha Nippon Conlux Münzauswähler
US5199545A (en) * 1991-02-28 1993-04-06 Takamisawa Cybernetics Co., Ltd. Metal body discriminating apparatus
DE10049390A1 (de) * 1999-10-06 2001-04-12 Nippon Conlux Co Ltd Münzinspektionsverfahren und -vorrichtung
US6340082B1 (en) * 1999-10-22 2002-01-22 Japan Tobacco Inc. Coin discriminating apparatus
EP1172772A2 (de) * 2000-06-30 2002-01-16 Azkoyen Medios de Pago, S.A. Verfahren und Einrichtung zum Feststellen von physikalischen Münzeigenschaften für ihre Identifikation

Similar Documents

Publication Publication Date Title
US6471030B1 (en) Coin sensing apparatus and method
US6047808A (en) Coin sensing apparatus and method
US6056104A (en) Coin sensing apparatus and method
US4184366A (en) Coin testing apparatus
US5351798A (en) Coin discrimination apparatus and method
JP3786887B2 (ja) 磁気検出器
US20040084278A1 (en) Coin-validation arrangement
US5199545A (en) Metal body discriminating apparatus
EP1668602B1 (de) Münzprüfer
US5715926A (en) Money validation
RU2155381C2 (ru) Устройство для проверки подлинности монет, жетонов и других плоских металлических предметов (варианты)
US6325197B1 (en) Method and device for checking coin for forgery
US6640955B1 (en) Coin inspection method and device
US8561777B2 (en) Coin sensor
EP1439499A1 (de) Verfahren und Vorrichtung zur Münzerkennung in einer Auswerteeinheit
US4124110A (en) Magnetic coin element sensor
CA2288297C (en) Method of and apparatus for determining authenticity of coins
RU2186422C2 (ru) Устройство для проверки подлинности монет, жетонов и других плоских металлических предметов
JPH0638088B2 (ja) 容量測定用回路
JP2966933B2 (ja) コイン検査方法及び装置
JPH0792849B2 (ja) 検銭装置
EP3287991A1 (de) Münzsensor
GB2266399A (en) Coin testing
GB2422941A (en) Coin validation
GB2040526A (en) Magnetic Coin Element Sensor

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT SE SI SK TR

AX Request for extension of the european patent

Extension state: AL LT LV MK RO

AKX Designation fees paid
REG Reference to a national code

Ref country code: DE

Ref legal event code: 8566

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20050129