JP5163272B2 - Optical sensor device for paper sheet classifier - Google Patents

Description

  The present invention relates to an optical sensor device for a paper sheet discriminator for identifying the authenticity, type, etc. of a paper sheet, and more particularly to an output of an optical sensor in a bill discriminator mounted on a money changer, a ball lending machine or a vending machine. The present invention relates to an optical sensor device for a paper sheet classifier capable of adjusting a level.

  Conventionally, paper sheets have been required to prevent counterfeiting and tampering due to their properties. In particular, in banknote discriminators mounted on money change machines, ball lending machines, vending machines, etc., it is important that a large number of discriminating optical sensors are arranged in order to collect banknote data and maintain their discrimination accuracy. . In addition, as a measure to prevent counterfeiting and falsification of paper sheets such as banknotes, various data such as infrared light transmission light quantity, red light transmission light quantity, and infrared light / red light transmission light ratio data are available. An optical sensor device that collects may be used. Further, in order to stably perform the identification operation of the identification optical sensor, it is necessary to adjust the light emission intensity of the light emitting element to a predetermined reference value when the optical sensor device is manufactured.

  Conventionally, in order to set or adjust the light intensity of an optical sensor, one variable resistor must be connected for each light emitting element, and manual adjustment must be made to obtain the optimum current value flowing through the light emitting element. I had to. However, the current adjustment of the light emitting element not only requires manual labor, but also because the operation is cumbersome, the current value adjustment circuit of the light emitting element that automatically adjusts the current of the identification light emitting element of the bill validator etc. (For example, refer to Patent Document 1).

FIG. 4 is a block diagram showing a configuration of a conventional optical sensor device used for bill recognition.
The optical sensor 100 includes two light emitting elements 101 and 102 and two light receiving elements 103 and 104. The light emitting elements 101 and 102 are each composed of LEDs (light emitting diodes) for two wavelengths of infrared and red. In the optical sensor 100 arranged in the transport path 105, an identification signal is read from a bill transported through the vicinity thereof. In the light receiving elements 103 and 104 of the optical sensor 100, an identification signal received through the transport path 105 is converted into an electrical signal, amplified by amplifiers 106 and 107, and a microcomputer (hereinafter referred to as a CPU) constituting an arithmetic control unit. .) Is input to 120.

  On the other hand, the light emitting elements 101 and 102 are connected to infrared LED lighting circuits 108 and 109 and red LED lighting circuits 110 and 111, respectively, and are supplied with power from predetermined DC power sources 112 and 113, respectively. The four lighting circuits 108 to 111 are connected to electronic volumes 114 to 117 whose resistance values are varied by the CPU 120 to control the current values flowing through the light emitting elements 101 and 102. In addition, a nonvolatile memory 121 is connected to the CPU 120.

In such a conventional optical sensor device, the resistance variable means (electronic volumes 114 to 117) includes a plurality of fixed resistors and a plurality of transistors in which one terminal of the fixed resistors is connected to one end of the light emitting element or its power supply. The total resistance value can be varied by a combination of ON of these transistors. And, in the adjustment mode of the CPU 120 for controlling the banknote discriminator, the ON combination of the transistors is changed while detecting the light emission amounts of the light emitting elements 101 and 102, and when the light emission amount matches a predetermined value suitable for banknote recognition, The ON combinations of the transistors are stored in the non-volatile memory 121, and the transistors are turned on in the normal banknote recognition mode so that the ON combinations stored in the memory 121 are obtained.
Japanese Patent Laid-Open No. 05-226079 (paragraph numbers [0010] to [0014], FIG. 1)

  In the bill discriminator described above, the optical sensor 100 including the two sets of light emitting elements 101 and 102 and the light receiving elements 103 and 104 is arranged as an identification sensor. However, when a larger number of identification sensors are arranged, Electronic volumes 114 to 117 as voltage adjusting means are required according to the number of sensors. As a result, the number of components such as resistors and transistor switches increases. Therefore, the area occupied by the voltage adjusting means in the printed circuit board of the paper sheet discriminator increases, making it difficult to reduce the size of the optical sensor device. In addition, since the number of parts increases in proportion to the number of optical sensors, there has been a problem of increasing the product cost in improving the identification accuracy and improving the counterfeit bill elimination performance.

  The present invention has been made in view of the above points, and an optical sensor for a paper sheet classifier for manufacturing a paper sheet classifier having high identification accuracy using a plurality of optical sensors at a low cost and in a small size. An object is to provide an apparatus.

In the present invention, in order to solve the above-mentioned problem, a paper sheet identification in which an optical sensor composed of a plurality of light emitting elements and light receiving elements is arranged in a passage of a paper sheet and identifies the authenticity, type, etc. of the paper sheet. An optical sensor device is provided. Light sensor device of the paper sheet recognition apparatus includes a storage unit for storing an adjustment resistance value based on the reference made light amount before Ki受 optical element, the resistance by the current value control signal corresponding to the previous SL Luminous element a voltage adjusting means for varying the value, and switching means for connecting said voltage regulating means is switched by time division and each of the light emitting elements, sequentially and said voltage regulating means switches said switching means and before Symbol luminous element And a control means for outputting the current value control signal to the voltage adjusting means based on the adjustment resistance value corresponding to the light emitting element stored in the storage means, and the light emitting element includes: A fixed resistor connected in parallel to the voltage adjusting means is provided, and the light emitting element that is not connected to the voltage adjusting means by the switching means has a predetermined size of electric power by the corresponding fixed resistor. The Ru Der those allowed to flow, respectively.

  In this optical sensor device, the storage means is, for example, a non-volatile memory, and stores the adjustment resistance value based on the amount of light received as a reference of each light receiving element. The voltage adjusting means is, for example, an electronic volume, and the resistance value is varied by a current value control signal corresponding to each light emitting element. The switching means is, for example, an analog switch, and the voltage adjusting means is switched and connected to each light emitting element in a time division manner. The control means is a CPU, for example, and outputs a current value control signal to the voltage adjustment means based on the adjustment resistance value corresponding to the light emitting element stored in the storage means.

  According to the present invention, since only one electronic volume as voltage adjusting means is required for a large number of light emitting elements, an optical sensor device can be configured at low cost. Therefore, by providing a large number of light emitting elements in the optical sensor device, it is possible to improve the identification accuracy of a paper sheet classifier such as banknotes and improve counterfeit bill elimination performance. Further, even if the number of photosensors is increased, the area occupied by the voltage adjusting means in the printed circuit board does not increase so much, so that the cost of the photosensor device can be suppressed.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration of an optical sensor device according to an embodiment.
The optical sensor 10 includes two light emitting elements 11 and 12 and two light receiving elements 13 and 14, and each of the light emitting elements 11 and 12 includes LEDs for two wavelengths of infrared and red. In the optical sensor 10 disposed in the transport path 15, the identification signal is read from the bills that are transported through the vicinity thereof. In the light receiving elements 13 and 14 of the optical sensor 10, the identification signal received through the transport path 15 is converted into an electrical signal, and further amplified by the amplifiers 16 and 17 to the CPU 30 constituting the arithmetic control unit. Entered.

  Infrared LED lighting circuits 18 and 19 and red LED lighting circuits 20 and 21 are connected to the light emitting elements 11 and 12, respectively, and power is supplied from predetermined DC power sources 22 and 23. The lighting circuits 18 to 21 are supplied with a lighting control signal from the CPU 30, and are controlled to turn on and off so that the infrared and red LEDs of the light emitting elements 11 and 12 emit light at a predetermined timing by the DC power sources 22 and 23. ing.

  The lighting circuits 18 to 21 are connected to the electronic volume 25 via the analog switch 24. The analog switch 24 connects the electronic volume 25 to the lighting circuits 18 to 21 in a time-sharing manner and is controlled by a control signal from the CPU 30. The electronic volume 25 is a circuit for controlling a current value flowing through the light emitting elements 11 and 12 and has a configuration shown in FIG. 2 to be described later, and its resistance value is variable by a current value control signal from the CPU 30. Is set.

  Further, a nonvolatile memory 31 is connected to the CPU 30, and information relating to the resistance value of the electronic volume 25 adjusted based on the amount of light received as a reference for each of the light receiving elements 13 and 14 in the adjustment mode of the CPU 30. Etc. are memorized.

  Further, the lighting circuits 18 to 21 are respectively connected to one ends of fixed resistors 26 to 29 connected in parallel to the electronic volume 25, and the other ends of these fixed resistors 26 to 29 are grounded. Therefore, even when the LED connected to each of the lighting circuits 18 to 21 is not connected to the electronic volume 25 by the analog switch 24, a current of a predetermined magnitude always flows through these fixed resistors 26 to 29. .

FIG. 2 is a block diagram showing a configuration of an electronic volume used in the optical sensor device of FIG.
Here, two reference resistors R11 and R12 connected in series, a transistor switch S1 for selecting this series resistor circuit, reference resistors R21 and R22 connected in series, a transistor switch S2, and the like are included. Yes. The transistor switches S1, S2 and the like are on / off controlled by the current value control signal from the CPU 30. The plurality of series resistance circuits are configured by reference resistors R11 to R42 having different resistance values, and various parallel resistance circuits can be configured by arbitrarily selecting these transistor switches S1 and S2. Therefore, the resistance value of the electronic volume 25 as a whole can be variably set by the current value control signal from the CPU 30.

  In the adjustment mode of the CPU 30, the ON combination of the transistor switches S1 and S2 in the electronic volume 25 is changed while detecting the light emission amounts of the light emitting elements 11 and 12, and the transistor when the light emission amount matches a predetermined value suitable for banknote identification. This is stored in the nonvolatile memory 31 as a combination of turning on the switches S1 and S2. Then, during normal bill recognition operation, the transistor switches S1 and S2 are turned on so that the on combination stored in the nonvolatile memory 31 is obtained.

FIG. 3 is a timing chart showing the blinking operation of the light emitting element in the optical sensor device of FIG.
FIG. 4A shows a timer interrupt signal for reading the identification signals of the light receiving elements 13 and 14 in the CPU 30. In the CPU 30, the interval between timings t1 and t2 is set to 1 ms, and the interval is divided into n so that 2n photosensors 10 are sequentially turned on by the analog switch 24. FIGS. 7B to 7E show lighting timings of the two light emitting elements 11 and 12 shown in the optical sensor device of FIG.

  At the first lighting timing t1, the LEDs of the infrared wavelengths of the light emitting elements 11, 12 are controlled to be turned on, and at the next lighting timing t2, the LEDs of the red wavelengths of the light emitting elements 11, 12 are controlled to be turned on. In addition, the lighting period T1 is divided into the front and rear halves. The first light emitting element 11 is turned on in the first half period, and the second light emitting element 12 is turned on in the second half period. The current flowing through each light emitting element 11, 12 is set by the CPU 30 controlling the electronic volume 25 based on the reference resistance value stored in the nonvolatile memory 31, and the light emission luminance of each light emitting element 11, 12 is set. Can be adjusted.

  As described above, the CPU 30 selects the corresponding optical sensor 10 and simultaneously controls the electronic volume 25 by the adjustment resistance value stored in the nonvolatile memory 31 at the time of adjustment. Although the optical sensor 10 is in the lighting state during the lighting period T1, if it is not selected, a minimum reference current (for example, 1 mA) is passed through the optical sensor 10 by the fixed resistors 26-29. Therefore, the optical sensor 10 can be driven thermally and stably.

  Therefore, even when a plurality of optical sensors 10 are used in the bill validator, the electronic volume 25 for voltage adjustment is configured by only one (one set) while maintaining the identification performance of the optical sensor 10. Can do. Further, even when the number of optical sensors 10 is further increased, the voltage adjusting electronic volume 25 can be kept as one, so that an increase in the area occupied in the printed circuit board of the bill validator can be suppressed and the counterfeit bill can be inexpensively produced. Exclusion performance can be improved.

It is a block diagram which shows the structure of the optical sensor apparatus which concerns on embodiment. It is a block diagram which shows the structure of the electronic volume used for the optical sensor apparatus of FIG. FIG. 2 is a timing chart showing a blinking operation of a light emitting element in the optical sensor device of FIG. 1. It is a block diagram which shows the structure of the conventional optical sensor apparatus used for banknote identification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Optical sensor 11,12 Light emitting element 13,14 Light receiving element 15 Carriage path 16,17 Amplifier 18-21 Lighting circuit 22,23 DC power supply 24 Analog switch 25 Electronic volume 26-29 Fixed resistance 30 CPU (microcomputer)
31 Nonvolatile memory

Claims (4)

In the optical sensor device of the paper sheet classifier for identifying the authenticity, type, etc. of the paper sheet, an optical sensor comprising a plurality of light emitting elements and light receiving elements is disposed in the path of the paper sheet.
Storage means for storing an adjustment resistance value based on the received light amount as a reference before Ki受 optical element,
A voltage adjusting means for varying the resistance value by the current value control signal corresponding to the previous SL Luminous element,
Switching means for switching and connecting the voltage adjusting means to each of the light emitting elements in a time-sharing manner;
Thereby connecting said voltage adjusting means by switching said switching means and before Symbol Luminous element sequentially, the current value control signal based on the adjustment resistance values corresponding to the light emitting device stored in the storage means Control means for outputting to the voltage adjusting means;
Equipped with a,
Each of the light emitting elements includes a fixed resistor connected in parallel to the voltage adjusting unit,
An optical sensor for a paper sheet discriminator, wherein a current of a predetermined magnitude is caused to flow through each of the light emitting elements not connected to the voltage adjusting means by the switching means. apparatus.   2. The optical sensor device for a paper sheet classifier according to claim 1, wherein the storage means is a non-volatile memory that stores the adjustment resistance value.   2. The optical sensor device for a paper sheet identification machine according to claim 1, wherein the optical sensor includes a plurality of light emitting elements connected to lighting circuits having different wavelengths.   The voltage adjustment means is composed of a plurality of reference resistors and a transistor switch for selecting the reference resistance, and is an electronic volume that adjusts a resistance value by selecting the transistor switch by the voltage adjustment means. The optical sensor device for a paper sheet discriminator according to claim 1.

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