JP4721509B2 - Paper sheet detection sensor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a paper sheet detection sensor for use in discriminating the type and authenticity of paper sheets such as banknotes.
[0002]
[Prior art]
Conventionally, there is JP-T 9-507326 as a technique in such a field. The apparatus described in this publication irradiates the banknotes with ultraviolet light, measures the level of ultraviolet light reflected by the banknotes using the first photocell, and at the same time, determines the amount of fluorescence generated on the banknotes by the second level. It measures with a photocell, compares each measured quantity with a reference level, and discriminates the authenticity of a banknote.
[0003]
[Problems to be solved by the invention]
However, the conventional apparatus described above has the following problems. That is, the amount of ultraviolet light irradiated on the banknote may become unstable at the beginning of lighting of the light source, and may vary with voltage fluctuation or deterioration over time. When inspected, there is a possibility that the authenticity of banknotes cannot be accurately detected.
[0004]
The present invention has been made to solve the above-described problems, and in particular, an object of the present invention is to provide a paper sheet detection sensor that appropriately monitors the light amount of a light emitting element in a housing.
[0005]
[Means for Solving the Problems]
The paper sheet detection sensor according to the present invention is a paper sheet detection sensor that irradiates light on a paper sheet and receives light from the surface of the paper sheet while the paper sheet is being conveyed. A light emitting element that receives light from the surface of the paper sheet through the light receiving window, and a light emitting element that irradiates light toward the conveyance path of the paper sheet through the illumination window; , by disposed toward the light-emitting element in the housing, an illumination monitor light-emitting element in the field of view illumination window enters and the field of view provided in a position not enter Bei example, the driving circuit board mounted to the housing Fix the lead part of the light emitting element, the lead part of the light receiving element, and the lead part of the illumination monitor, bend the lead part of the illumination monitor, and place the illumination monitor so that the light receiving center line of the illumination monitor faces the drive circuit board side It was made to be characterized.
[0006]
If the light applied to the paper sheets being transported is not always managed in a certain state, there is a risk that accurate paper sheet inspection (for example, bill type or authenticity) may not be possible. The paper sheets are continuously transported with a certain gap, and the light emitting element always illuminates the paper sheet portion and the paper sheet non-existing portion (interval between the paper sheets) on the transport path. It will be. Thereby, the case where the reflected light from the paper enters from the illumination window and the case where the reflected light from the paper does not occur occur, and the amount of light incident on the illumination window changes intermittently. Further, the amount of light reflected on the surface varies depending on the type of paper sheet. Therefore, when the illumination monitor is randomly arranged in the housing, the amount of light received by the illumination monitor changes intermittently due to the influence of the paper sheet, and it is difficult to accurately monitor the light quantity change of the light emitting element. It was. Therefore, the illumination monitor applied to the paper sheet detection sensor of the present invention is directed to the light emitting element at a position where the light emitting element enters the field of view and the illumination window does not enter the field of view. That is, as a result of placing the illumination window outside the field of view of the illumination monitor, the influence of light reflected from the paper sheet and incident from the illumination window is eliminated as much as possible, and as a result, the effect of continuous conveyance of the paper sheet And the effect of the type of paper is extremely reduced.
[0007]
In addition, the lead part of the light emitting element, the lead part of the light receiving element, and the lead part of the illumination monitor are fixed to the drive circuit board attached to the housing, the lead part of the illumination monitor is bent, and the light receiving center line of the illumination monitor is driven. Ru is arranged illumination monitor to direct toward the circuit board. That is, by bending the lead part of the illumination monitor so that the light receiving center line of the illumination monitor is directed to the drive circuit board side, the illumination part of the illumination monitor can be easily directed to the light emitting element side. The lead part, the lead part of the light receiving element, and the lead part of the illumination monitor can be fixed on the same drive circuit board by soldering or the like.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a preferred embodiment of a paper sheet detection sensor according to the present invention will be described in detail with reference to the drawings.
[0009]
FIG. 1 is a cross-sectional view showing a paper sheet inspection device 1, and the paper sheet inspection device 1 is an object of inspection for authenticity determination of banknotes as an example of paper sheets. Specifically, it is a discrimination between a color copied counterfeit bill and a regular bill. This color copy sheet contains a large amount of fluorescent components, and authenticity determination is performed by paying attention to this point.
[0010]
The paper sheet inspection device 1 is provided with a linear conveyance path 4 formed so as to be sandwiched between upper and lower guide plates 2 and 3. In the middle of the conveyance path 4, conveyance rollers 5 and 6 are provided. It arrange | positions and the banknote 7 is reliably conveyed toward the discharge side by each conveyance roller 5 and 6. FIG. A bill recognizing device 8 for identifying a denomination is arranged in the middle of the transport path 4.
[0011]
Although not shown, the bill (paper sheet) recognition device 8 has a structure in which the surface of the bill 7 is illuminated by a light source such as an LED and the reflected light from the bill 7 is captured by a CCD camera. And the collation with the image imaged with the camera and known image data is performed, and the money type of a banknote is discriminated. However, in recent years, due to the high accuracy of color copying, it is difficult to determine the authenticity of the banknote 7 by image recognition alone.
[0012]
Therefore, a fluorescence detection sensor 10 that is an example of a paper sheet detection sensor is disposed on the upstream side of the bill recognition device 8. As shown in FIG. 2, the fluorescence detection sensor 10 has a partition portion 20 that divides the internal space of the housing 11 in the vertical direction. The partition portion 20 divides the light emitting element 12 and the light receiving element 16, and the housing. 11 window portions 13 are divided into an illumination window 23 and a light receiving window 24. And in one space formed by the partition part 20 of the housing 11, an ultraviolet LED (light emitting element) 12 that irradiates light toward the transport path 4 of the banknote 7 is accommodated, and the ultraviolet LED 12 has a lead part 12a. And is fixed to the drive circuit board 25 of the housing 11.
[0013]
The LED 12 used here is an ultraviolet lamp containing a visible light component. The reason why the LED 12 is used as the light source is that even if the housing 11 is small, the housing space is small, the luminance variation is small, and the light fluctuation with time is small. 10 is optimal.
[0014]
A rectangular window portion 13 is provided on the lower surface of the housing 11 so as to face the drive circuit board 25 on the upper surface. A dust-proof glass plate 14 is fitted into the window portion 13 with an adhesive or the like. For No. 14, quartz glass having an extremely high ultraviolet transmittance is employed. Further, on the light emitting element 12 side, an ultraviolet transmission filter 15 is attached to the upper surface (inner surface) of the dust-proof glass plate 14 so as to match the illumination window 23. Accordingly, when the light emitted from the ultraviolet LED 12 passes through the ultraviolet transmission filter 15, an ultraviolet component (for example, about 300 to 400 nm) is emitted to the transport path 4 through the dust-proof glass plate 14. And the banknote 7 sent to the right under the dust-proof glass plate 14 through the conveyance path | route 4 is illuminated with this ultraviolet-ray.
[0015]
A light receiving element (photosensor) 16 for detecting fluorescence emitted from the surface of the banknote 7 is accommodated in the other space formed by the partition portion 20 of the housing 11. It fixes to the drive circuit board 25 of the housing 11 via the part 16a. Therefore, when the banknote 7 illuminated by the ultraviolet rays contains a fluorescent component, the excited fluorescence is emitted from the banknote 7 and is detected by the light receiving element 16. That is, when the counterfeit banknote 7 that has been color-copied is fed into the transport path 4, the light-receiving element 16 detects a large amount of fluorescence because the color copy paper contains a large amount of fluorescence components. On the other hand, the regular banknote contains almost no fluorescent component, and the voltage change of the sensor 16 is extremely small.
[0016]
On the light receiving element 16 side, an ultraviolet cut filter 17 is attached to the upper surface (inner surface) of the dust-proof glass plate 14 so as to match the light receiving window 24. The reason for adopting such an ultraviolet cut filter 17 is that light reflected on the surface of the banknote 7 contains an ultraviolet component, and this ultraviolet component has high energy characteristics, so that erroneous detection is avoided. This is because it is necessary to remove the ultraviolet component in order to achieve this.
[0017]
Here, the light applied to the banknote 7 in the middle of conveyance may not be able to accurately inspect the banknote 7 (for example, the type and authenticity of the banknote) unless it is always managed in a constant state. The banknote 7 on 4 is continuously transported at a high speed with a predetermined gap, and the light emitting element 12 always moves the part of the banknote 7 and the part where the banknote 7 does not exist (interval between the banknotes 7) on the transport path 4. It will continue to illuminate. Thereby, the case where the reflected light from the banknote 7 enters from the illumination window 23 and the case where the reflected light from the banknote 7 does not occur occur, and the amount of light entering the illumination window 23 changes intermittently.
[0018]
Furthermore, the amount of light reflected differs depending on the type of banknote 7 (for example, a thousand-yen bill and a 10,000-yen bill), regardless of whether each sheet is inspected or continuously examined. That is, every time the denomination of the bill changes, the amount of light incident on the illumination window 23 changes intermittently.
[0019]
Therefore, an illumination monitor 18 made of a photosensor is disposed on the light emitting element 12 side of the housing 11 in order to accurately monitor the light quantity change of the light emitting element 12. The illumination monitor 18 emits light at a position where the light emitting element 12 enters the field of view of the illumination monitor 18 and the illumination window 23 does not enter the field of view in order to eliminate the influence of the reflected light on the banknote 7 as much as possible. It is directed to the element 12. Therefore, in this fluorescence detection sensor 10, an output signal is generated from the illumination monitor 18 in a state where the influence of the reflected light from the banknote 7 is eliminated as much as possible, and based on the voltage value of this output signal, the light emitting element 12 The amount of light is managed over time. The illumination monitor 18 is the same component as the light receiving element 16, and has a wide field of view (for example, a viewing angle α = 110 degrees).
[0020]
Further, when the lead portion 18a of the illumination monitor 18 is bent in a V shape so that the light receiving center line P of the illumination monitor 18 faces the drive circuit substrate 25 side, the lead portion 18a is fixed to the drive circuit substrate 25. The light receiving surface 18b of the illumination monitor 18 can be easily directed to the light emitting element 12 side. Moreover, by bending the lead portion 18a, the lead portion 12a of the light emitting element 12, the lead portion 16a of the light receiving element 16, and the lead portion 18a of the illumination monitor 18 are arranged on the same drive circuit board 25 by soldering or the like. Can be fixed.
[0021]
Since the illumination monitor 18 has a wide field of view, if the bending angle β of the lead portion 18a is in the range of 30 to 45 degrees, the light receiving element 12 can be accommodated in the field of view of the illumination monitor 18. Out. Thus, having a predetermined allowable width (for example, 15 degrees) at the bending angle β means that the illumination monitor 18 does not require strict setting, and improves the assembly workability of the sensor 10. .
[0022]
The paper sheet detection sensor according to the present invention is not limited to the above-described embodiment. For example, the paper sheet detection sensor is not limited to fluorescence detection, and may be a sensor that detects light of other wavelengths. Further, the paper sheets are not limited to banknotes, but may be cards or securities.
[0023]
【The invention's effect】
Since the paper sheet detection sensor according to the present invention is configured as described above, the following effects are obtained. That is, in the middle of transporting paper sheets, a paper sheet detection sensor that irradiates the paper sheets with light and receives light from the surface of the paper sheets is accommodated in the housing and is passed through the illumination window. A light-emitting element that emits light toward the leaf transport path, a light-receiving element that is received in the housing and receives light from the surface of the paper sheet through the light-receiving window, and toward the light-emitting element in the housing so arranged, e Bei an illumination monitor light-emitting element in the field of view illumination window enters and the field of view provided in a position not enter, the lead portion and the light receiving element of the light emitting element driving circuit board mounted to the housing By fixing the lead part and the lead part of the illumination monitor, bending the lead part of the illumination monitor, and arranging the illumination monitor so that the light receiving center line of the illumination monitor faces the drive circuit board side, light emission in the housing The light quantity of the element can be monitored appropriately.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an example of a paper sheet inspection device to which a paper sheet detection sensor according to the present invention is applied.
FIG. 2 is a cross-sectional view showing an embodiment of a paper sheet detection sensor according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 4 ... Conveyance path, 7 ... Banknote (paper sheet), 10 ... Fluorescence detection sensor (paper sheet detection sensor), 11 ... Housing, 12 ... LED (light emitting element), 12a ... Lead part, 16 ... Light receiving element, 16a DESCRIPTION OF SYMBOLS ... Lead part, 18 ... Illumination monitor, 18a ... Lead part, 23 ... Illumination window, 24 ... Light receiving window, 25 ... Drive circuit board, P ... Light receiving center line.

Claims (1)

In the middle of conveying the paper sheet, in the paper sheet detection sensor that irradiates light to the paper sheet and receives light from the surface of the paper sheet,
A light emitting element that is housed in a housing and irradiates light toward the transport path of the paper sheet through an illumination window;
A light receiving element that is housed in the housing and receives light from the surface of the paper sheet through a light receiving window;
Said inside housing is located towards the light emitting element, Bei example an illumination monitor the light emitting element within the field of view is the illumination window enters and within the field of view provided in a position not enter,
The lead part of the light emitting element, the lead part of the light receiving element, and the lead part of the illumination monitor are fixed to a drive circuit board attached to the housing, and the lead part of the illumination monitor is bent, A paper sheet detection sensor , wherein the illumination monitor is arranged so that a light receiving center line is directed toward the drive circuit board .

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