JP2006099197A - Bill identification unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To precisely detect a magnetic pattern of printed ink on a banknote with a wide dynamic range in a banknote identification unit structured of simple hardware. <P>SOLUTION: The banknote is transferred at a predetermined speed, and a trace data is obtained by detecting the magnetic pattern of the printed ink on the transferred banknote by means of a magnetic head, and by amplifying the detected magnetic pattern in a first amplifier circuit (sense amplifier). By comparing the above signal with a reference voltage, a binary signal is obtained, which is then integrated in an integrating circuit and amplified, so as to obtain an analog data. The binary signal and the analog data are respectively compared with reference data, and identification of the banknote is performed. By obtaining two data, each amplified with a different amplification factor from the analog data, respective magnetic patterns in a strong magnetic point and a weak magnetic point can be identified simply and accurately. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a banknote recognition apparatus, and more particularly to a banknote identification apparatus that can detect in detail a magnetic pattern of printing ink on a banknote in a wide dynamic range.

  The ink used for printing a banknote contains a magnetic component, but the strength varies depending on the pattern of the banknote. In order to identify these banknotes, there is a method of reading the magnetism contained in the banknotes using a magnetic head. When classified based on an output with a constant amplification factor, an output at a portion with a large magnetic component can be effectively identified, but an output at a portion with a small magnetic component hardly changes in voltage, making identification difficult. The following are some conventional banknote identification methods.

  The “banknote identification device” disclosed in Patent Document 1 can accurately identify banknotes having different print patterns. The magnetism contained in the predetermined printing part of the banknote printed with magnetic ink is detected by scanning. The type of bill is determined by pulsing the detection signal and comparing it with a reference signal stored in advance.

  The “banknote identification device” disclosed in Patent Document 2 is such that the acceptance rate of true banknotes does not decrease even if the transport speed of the transport means decreases. The amplification factor of the amplification unit is switched according to the conveyance speed of the conveyance unit. Alternatively, the reference voltage level of the voltage comparison means is switched. In this way, by analyzing the voltage level characteristic of the magnetic signal of the banknote, even if the transport speed of the transport means decreases due to a decrease in the supply power voltage to the banknote recognition device or a change in the ambient temperature, the banknote recognition performance Can be maintained.

  The "automatic adjustment device for a magnetic detection circuit in a banknote counter" disclosed in Patent Document 3 improves the reliability of banknote processing by precisely adjusting the level of a magnetic ink detection signal for banknotes. is there. The automatic adjustment device for the magnetic detection circuit of the bill counter is composed of a magnetic sensor, preamplifier, offset control D / A converter, voltage control amplifier, gain control D / A converter, A / D converter, and central processing unit. . The offset level is adjusted while the magnetic sensor has not detected the magnetic reference paper. After completion of the offset level adjustment, one sheet of magnetic reference paper is flowed to the conveyance path of the bill counter, and gain level adjustment is performed based on a signal detected from the magnetic reference paper.

  The “banknote identification device” disclosed in Patent Document 4 is a banknote identification apparatus that identifies a banknote using a differential magnetic head that detects the magnetic strength of a banknote to be transported. Even if the speed is set, a magnetic signal which is not affected by this can be obtained. The pulse generation means generates a pulse proportional to the bill conveyance distance. The signal correction means corrects the output signal from the magnetic detection means (magnetic head) using a de-emphasis circuit. Every time a predetermined pulse is generated by the pulse generation means, the signal from the magnetic detection means corrected by the signal correction means is sampled by the sampling means.

The “paper counting device” disclosed in Patent Document 5 is a bill counting device that can easily and accurately adjust the sensitivity of a magnetic sensor. The magnetic detection means outputs a signal value corresponding to the magnetic component amounts of a plurality of blocks included in the test medium having a magnetic component. The storage means stores each signal value output from the magnetic detection means. The difference calculation means compares each signal value stored in the storage means to determine a difference between the lowest signal value and the highest signal value. The average value calculation means discards the maximum signal value and calculates the average value of the remaining signal values when the difference calculated by the difference calculation means is equal to or greater than a preset set value. On the other hand, if the difference is less than the set value, the average value of all signal values is calculated. The average value calculated by the average value calculation means is notified to the outside by the notification means.
JP 61-82290 JP Japanese Patent Laid-Open No. 03-223994 JP 05-094569 A Japanese Unexamined Patent Publication No. 09-180026 Japanese Patent Laid-Open No. 11-066267

  However, the conventional banknote recognition apparatus has a problem that paper sheets obtained by copying a rough magnetic component included in a banknote may be identified as a genuine note. In order to increase the accuracy, a very precise magnetic sensor and amplifier are required, and there is a problem that the device becomes large and difficult to manage, and too expensive.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and to detect in detail a magnetic pattern of printing ink on a banknote in a wide dynamic range with a simple hardware banknote identification apparatus.

  In order to solve the above-described problems, in the present invention, the banknote recognition device includes a transport unit that transports banknotes at a predetermined speed, a magnetic head that detects a magnetic pattern of printing ink on banknotes transported by the transport unit, A first amplifying circuit for amplifying a signal detected by the magnetic head; an integrating circuit for integrating the output signal of the first amplifying circuit; a second amplifying circuit for amplifying the output signal of the integrating circuit; and an output signal of the second amplifying circuit First A / D conversion means for converting the output signal of the second amplification circuit, a third amplification circuit for amplifying the output signal of the second amplification circuit, and a second A / D for converting the output signal of the third amplification circuit to the second digital signal. D conversion means, a comparison circuit for comparing the output signal of the first amplifier circuit with the reference voltage and outputting a binary signal, a first comparison means for comparing the first digital signal with the first reference pattern, Digital signal as second reference pattern A second comparing means for comparing, a binary comparing means for comparing a binary signal with a binary reference pattern, an output signal of the first comparing means, an output signal of the second comparing means, and an output signal of the binary comparing means; And determining means for determining the authenticity of the banknote based on the above.

  As described above, according to the present invention, the output signal of the magnetic head is set to two outputs with different amplification factors, so that each of the magnetic pattern at the strong magnetic part and the magnetic pattern at the weak magnetic part can be easily and accurately obtained. Can be identified. Further, the identification accuracy can be improved by converting the data obtained by directly converting the output signal of the magnetic head into a binary signal as the identification data.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to FIGS.

  In the first embodiment of the present invention, the magnetic pattern of the banknote printing ink is detected, integrated, amplified, A / D converted into digital data, and the magnetic pattern data is compared with a reference voltage to be binary data. It is a banknote identification apparatus which compares two data with a reference pattern, respectively, and determines the authenticity of a banknote.

  FIG. 1 is a diagram for explaining an analog / digital conversion method of banknote magnetic data of the banknote identification apparatus according to the first embodiment of the present invention. FIG. 1A shows model data obtained by tracing a magnetic pattern of printing ink of a certain banknote with a magnetic head. FIG. 1B shows digital data obtained by converting output data of the magnetic head into binary data based on a threshold value. FIG. 1C shows analog data obtained by integrating the output data of the magnetic head.

  FIG. 2 is a block diagram showing the overall configuration of the banknote recognition / conveyance unit of the banknote recognition apparatus. In FIG. 2, the magnetic head 1 is a means for detecting the magnetic pattern of the printing ink of banknotes. The first amplifier circuit 2 is a circuit that amplifies a signal detected by the magnetic head. The integrating circuit 3 is a circuit that integrates the output signal of the first amplifier circuit. The second amplifier circuit 4 is a circuit that amplifies the output signal of the integrating circuit. The comparison circuit 6 is a circuit that compares the output signal of the first amplifier circuit with a reference voltage. The CPU 7 is a logical operation device that performs A / D conversion on the output signal of the second amplification circuit, compares the reference signal with the reference pattern, determines the authenticity of the bill, and controls the motor. The motor control circuit 8 is a circuit that controls the rotation of the motor. The motor 9 is means for transporting banknotes at a predetermined speed. The encoder 10 is means for detecting the rotational speed of the motor.

  The operation of the bill validator in the embodiment of the present invention configured as described above will be described. Initially, the conversion method of the magnetic data of a banknote is demonstrated, referring FIG. Trace data shown in FIG. 1 (a) is obtained by conveying a banknote at a predetermined speed, detecting a magnetic pattern of printing ink of the banknote being conveyed by a magnetic head, and amplifying it by a first amplifier circuit (sense amplifier). Get. The position and width of the banknote detected by the magnetic head are set to the optimum position and width according to the type of banknote. Usually, magnetic patterns at a plurality of positions are detected, but one case is shown as an example.

  An output signal obtained by amplifying the signal detected by the magnetic head by the first amplifier circuit and the reference voltage are compared by a comparison circuit to obtain a binary signal shown in FIG. Further, the signal amplified by the first amplifier circuit is integrated by the integrating circuit and amplified by the second amplifier circuit to obtain analog data shown in FIG. This analog data is converted into a digital signal by an A / D converter.

  Next, the operation of the bill validator will be described in detail with reference to FIG. The CPU 7 controls the motor control circuit 8, and the motor 9 transports the banknotes at a predetermined speed. The rotational speed of the motor 9 is detected by the encoder 10 and fed back to the CPU 7. Thereby, a banknote can be conveyed at arbitrary fixed speeds. The magnetic head 1 detects the magnetic pattern of the printing ink of the bills being conveyed. A signal detected by the magnetic head 1 is amplified by the first amplifier circuit 2. The output signal of the first amplifier circuit 2 is integrated by the integration circuit 3. The output signal of the integrating circuit 3 is amplified by the second amplifier circuit 4.

  An analog signal output from the second amplifier circuit 4 is input to the CPU 7. On the other hand, the output signal of the first amplifier circuit 2 is compared with the reference voltage by the comparison circuit 6, and a binary signal is output and input to the CPU 7. An analog signal output from the second amplifier circuit 4 is converted into a digital signal by an A / D converter built in the CPU 7. This digital signal is compared with a digital reference pattern. Also, the binary signal is compared with the binary reference pattern. Based on these comparison results, the authenticity of the banknote is determined.

  Next, the procedure of the banknote identification method of a banknote identification device is demonstrated, referring the flowchart of FIG. In Step 1, convert the analog data of the magnetic waveform into digital data. In Step 2, bills are identified by comparing digital data with reference data. In Step 3, check whether there is any problem in the identification result. If there is no problem, a bill recognition termination process is performed in Step 6. If there is a problem, Step 4 compares the binary data with the binary reference data to perform bill recognition. In Step5, check whether there is any problem in the identification result. If there is no problem, a bill recognition termination process is performed in Step 6. If there is a problem, error processing is performed in Step 7.

  In this example, bill recognition is performed using digital data preferentially, but bill recognition may be performed using binary data preferentially. Moreover, you may make it judge that it is a genuine note only when both data are always utilized and banknote identification is performed and both can be identified.

  As described above, in the first embodiment of the present invention, the banknote recognition device detects the magnetic pattern of the printing ink of the banknote, integrates and amplifies it, A / D converts it into digital data, and uses the magnetic pattern data as the reference voltage. Compared to binary data, the two pieces of data are each compared with a reference pattern to determine the authenticity of the banknote, so the banknote identification accuracy can be increased.

  In the second embodiment of the present invention, the magnetic pattern of the printing ink of the banknote is detected, integrated and amplified with two kinds of gains, respectively, A / D converted into digital data, and the two data are respectively compared with the reference pattern. It is a banknote identification device which determines the authenticity of a banknote.

  FIG. 4 is a diagram for explaining two digital conversion methods of banknote magnetic data of the banknote recognition apparatus. FIG. 4A shows model data obtained by tracing a magnetic pattern of printing ink of a certain banknote with a magnetic head. FIG. 4B shows analog data obtained by integrating the output data of the magnetic head and amplifying it with a small amplification degree. FIG. 4C shows analog data obtained by integrating the output data of the magnetic head and amplifying it with a large amplification degree.

  FIG. 5 is a block diagram showing the overall configuration of the banknote recognition / conveyance unit of the banknote recognition apparatus. In FIG. 5, the magnetic head 1 is a means for detecting the magnetic pattern of the printing ink of banknotes. The first amplifier circuit 2 is a circuit that amplifies a signal detected by the magnetic head. The integrating circuit 3 is a circuit that integrates the output signal of the first amplifier circuit. The second amplifier circuit 4 is a circuit that amplifies the output signal of the integrating circuit. The third amplifier circuit 5 is a circuit that amplifies the output signal of the second amplifier circuit. The CPU 7 is a logical operation device that performs A / D conversion on the output signals of the second amplifier circuit and the third amplifier circuit, compares the reference signal with the reference pattern, determines the authenticity of the bill, and controls the motor.

  Operation | movement of the banknote identification device in Example 2 of this invention comprised as mentioned above is demonstrated. Initially, the conversion method of the magnetic data of a banknote is demonstrated, referring FIG. Trace data shown in FIG. 4 (a), in which a bill is transported at a predetermined speed, a magnetic pattern of printed ink on the bill being transported is detected by a magnetic head and amplified by a first amplifier circuit (sense amplifier). Get.

  The signal amplified by the first amplifier circuit is integrated by the integrating circuit and amplified by the second amplifier circuit to obtain analog data shown in FIG. 4B. This analog data is converted into a digital signal by an A / D converter. Further, the signal amplified by the second amplifier circuit is amplified by the third amplifier circuit to obtain analog data shown in FIG. In this analog data, a portion with a large amplitude is lost due to saturation, but a portion with a small amplitude is amplified to an identifiable level. This analog data is converted into a digital signal by an A / D converter.

  Next, the operation of the bill validator will be described in detail with reference to FIG. The magnetic head 1 detects the magnetic pattern of the printing ink of the bills being conveyed. A signal detected by the magnetic head 1 is amplified by the first amplifier circuit 2. The output signal of the first amplifier circuit 2 is integrated by the integration circuit 3. The output signal of the integrating circuit 3 is amplified by the second amplifier circuit 4. An analog signal output from the second amplifier circuit 4 is input to the CPU 7. The output signal of the second amplifier circuit 4 is amplified by the third amplifier circuit 5. An analog signal output from the third amplifier circuit 5 is input to the CPU 7.

  The analog signal output from the second amplifier circuit 4 is converted into a digital signal by an A / D converter built in the CPU 7. This digital signal is compared with a digital reference pattern. The analog signal output from the third amplifier circuit 5 is converted to a digital signal by an A / D converter built in the CPU 7. This digital signal is compared with a digital reference pattern. Based on these comparison results, the authenticity of the banknote is determined.

  Next, the procedure of the banknote identification method of a banknote identification device is demonstrated, referring the flowchart of FIG. In Step 11, the two analog data of the magnetic waveform are converted into digital data. In Step 12, banknote identification is performed by comparing digital data with a small amplification level with reference data. In Step 13, check whether there is any problem with the digital data. That is, it is examined whether data having a small amplitude is lost due to A / D conversion. If there is a problem, in step 14, banknote identification is performed by comparing digital data with a large amplification degree with reference data. In Step 15, check whether there is any problem in the identification result. If there is a problem, error processing is performed in Step 16. If there is no problem, a banknote recognition end process is performed in Step 17.

  In this example, banknote recognition is performed using digital data with low amplification preferentially, but banknote identification may be performed using digital data with high amplification preferentially. Moreover, you may make it judge that it is a genuine note only when both data are always utilized and banknote identification is performed and both can be identified.

  As described above, in the second embodiment of the present invention, the banknote identification device detects the magnetic pattern of the printing ink of the banknote, integrates and amplifies it with two types of gains, and each A / D converts it into digital data. Since the two pieces of data are each compared with the reference pattern to determine the authenticity of the banknote, each of the magnetic pattern of the strong magnetism and the magnetic pattern of the weak magnetism can be easily and accurately identified.

  In the third embodiment of the present invention, the magnetic pattern of the printing ink of the banknote is detected, integrated, amplified by two types of gains, A / D converted, and the binary data obtained by comparing the magnetic pattern data with the reference voltage. The bill identification device determines the authenticity of the bill by comparing each of the three data with a reference pattern.

  FIG. 7 is a block diagram showing the overall configuration of the banknote recognition / conveyance section of the banknote recognition apparatus in Embodiment 3 of the present invention. In FIG. 3, a magnetic head 1 is a means for detecting a magnetic pattern of banknote printing ink. The first amplifier circuit 2 is a circuit that amplifies a signal detected by the magnetic head. The integrating circuit 3 is a circuit that integrates the output signal of the first amplifier circuit. The second amplifier circuit 4 is a circuit that amplifies the output signal of the integrating circuit. The third amplifier circuit 5 is a circuit that amplifies the output signal of the second amplifier circuit. The comparison circuit 6 is a circuit that compares the output signal of the first amplifier circuit with a reference voltage. The CPU 7 is a logical operation device that performs A / D conversion on the output signals of the second amplifier circuit and the third amplifier circuit, compares the reference signal with the reference pattern, determines the authenticity of the bill, and controls the motor.

  Operation | movement of the banknote identification device in Example 3 of this invention comprised as mentioned above is demonstrated. As shown in FIG. 7, the magnetic pattern of the printing ink of the bill to be conveyed is detected by the magnetic head 1. A signal detected by the magnetic head 1 is amplified by the first amplifier circuit 2. The output signal of the first amplifier circuit 2 is integrated by the integration circuit 3. The output signal of the integrating circuit 3 is amplified by the second amplifier circuit 4. An analog signal output from the second amplifier circuit 4 is input to the CPU 7. The output signal of the second amplifier circuit 4 is amplified by the third amplifier circuit 5. An analog signal output from the third amplifier circuit 5 is input to the CPU 7. On the other hand, the output signal of the first amplifier circuit 2 is compared with the reference voltage by the comparison circuit 6, and a binary signal is output and input to the CPU 7.

  An analog signal output from the second amplifier circuit 4 is converted into a digital signal by an A / D converter built in the CPU 7. The analog signal output from the third amplifier circuit 5 is converted into a digital signal by an A / D converter built in the CPU 7. These digital signals are compared with a digital reference pattern. Also, the binary signal is compared with the binary reference pattern. Based on these comparison results, the authenticity of the banknote is determined.

  The banknote identification method of a banknote identification device is demonstrated referring the flowchart of FIG. In Step 21, the two analog data of the magnetic waveform are converted into digital data. In Step 22, bill data is identified by comparing the digital data with a small amplification degree with the reference data. In Step 23, the digital data is checked for problems. That is, it is examined whether data having a small amplitude is lost. If there is a problem, in step 24, banknote identification is performed by comparing digital data with a large amplification degree with reference data. In Step 25, the identification result is checked for problems. If there is no problem, a bill recognition termination process is performed in Step 29. If there is a problem, in step 26, the binary data is compared with the binary reference data to perform bill recognition. In Step 27, the identification result is checked for problems. If there is no problem, a bill recognition termination process is performed in Step 29. If there is a problem, error processing is performed in Step 28.

  In this example, banknote recognition is performed using digital data with low amplification preferentially, but banknote identification may be performed using digital data with high amplification preferentially. Banknote recognition may be performed using binary data preferentially. Alternatively, the bill may be identified using three data at all times, and may be determined as a genuine note only when all three types can be identified. Or you may make it judge that it is a genuine note, when it can identify in any two ways.

  As described above, in the third embodiment of the present invention, the banknote identification device detects the magnetic pattern of the printing ink of the banknote, integrates and amplifies it with two types of gains, respectively A / D converts, and magnetic pattern data Is compared with the reference voltage, and the binary data is set, and the three data are respectively compared with the reference pattern to determine the authenticity of the banknote. Easy and accurate identification. Further, the identification accuracy can be improved by converting the data obtained by directly converting the output signal of the magnetic head into a binary signal as the identification data.

  The banknote identification device of the present invention can be used in a vending machine, a money changer, or the like as a device that can accurately identify banknotes with simple hardware. Moreover, since it is applicable not only to a banknote but to a medium mixed with a magnetic material, it can also be applied as an identification device for various securities and other printed matter.

It is a figure explaining the analog / digital conversion method of the banknote magnetic data of the banknote identification device in Example 1 of this invention. It is a figure which shows the banknote identification and conveyance whole structure of the banknote identification device in Example 1 of this invention. It is a flowchart which shows the procedure of the banknote identification method of the banknote identification apparatus in Example 1 of this invention. It is a figure explaining the analog / digital conversion method of the bill magnetic data of the bill discernment device in Example 2 of the present invention. It is a figure which shows the whole banknote identification and conveyance part structure of the banknote identification device in Example 2 of this invention. It is a flowchart which shows the procedure of the banknote identification method of the banknote identification apparatus in Example 2 of this invention. It is a figure which shows the banknote identification / conveyance part whole structure of the banknote identification apparatus in Example 3 of this invention. It is a flowchart which shows the procedure of the banknote identification method of the banknote identification device in Example 3 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Magnetic head, 2 ... 1st amplifier circuit, 3 ... Integration circuit, 4 ... 2nd amplifier circuit, 5 ... 3rd amplifier circuit, 6 ... Comparison circuit, 7 ..CPU, 8 ... motor control circuit, 9 ... motor, 10 ... encoder.

Claims (3)

A conveying means for conveying a bill at a predetermined speed; a magnetic head for detecting a magnetic pattern of printing ink on the bill conveyed by the conveying means; a first amplifier circuit for amplifying a signal detected by the magnetic head; An integration circuit for integrating the output signal of the first amplifier circuit; a second amplifier circuit for amplifying the output signal of the integration circuit; and a first A / D converter for converting the output signal of the second amplifier circuit into a first digital signal. Means for comparing the output signal of the first amplifier circuit with a reference voltage and outputting a binary signal; first comparing means for comparing the first digital signal with a first reference pattern; Binary comparison means for comparing a value signal with a binary reference pattern; and determination means for determining the authenticity of the bill based on the output signal of the first comparison means and the output signal of the binary comparison means. It is characterized by Nusa identification device. A conveying means for conveying a bill at a predetermined speed; a magnetic head for detecting a magnetic pattern of printing ink on the bill conveyed by the conveying means; a first amplifier circuit for amplifying a signal detected by the magnetic head; An integration circuit for integrating the output signal of the first amplifier circuit; a second amplifier circuit for amplifying the output signal of the integration circuit; and a first A / D converter for converting the output signal of the second amplifier circuit into a first digital signal. Means, a third amplifying circuit for amplifying the output signal of the second amplifying circuit, a second A / D converting means for converting the output signal of the third amplifying circuit into a second digital signal, and the first digital signal First comparison means for comparing with a first reference pattern; second comparison means for comparing the second digital signal with a second reference pattern; an output signal of the first comparison means and an output signal of the second comparison means; Based on before Bill identifying apparatus characterized by comprising a determination means for determining authenticity of the bill. A conveying means for conveying a bill at a predetermined speed; a magnetic head for detecting a magnetic pattern of printing ink on the bill conveyed by the conveying means; a first amplification circuit for amplifying a signal detected by the magnetic head; An integration circuit for integrating the output signal of the first amplifier circuit; a second amplifier circuit for amplifying the output signal of the integration circuit; and a first A / D converter for converting the output signal of the second amplifier circuit into a first digital signal. Means, a third amplifying circuit for amplifying the output signal of the second amplifying circuit, a second A / D converting means for converting the output signal of the third amplifying circuit into a second digital signal, and a first amplifying circuit. A comparison circuit that compares the output signal with a reference voltage and outputs a binary signal; first comparison means for comparing the first digital signal with a first reference pattern; and the second digital signal with a second reference pattern Second ratio to compare Means, a binary comparison means for comparing the binary signal with a binary reference pattern, an output signal of the first comparison means, an output signal of the second comparison means, and an output signal of the binary comparison means. And determining means for determining the authenticity of the banknote.

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