JPH0831158B2 - Thickness detection device for paper sheets - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Industrial field of application) The present invention is a paper sheet for detecting the thickness of a banknote to be conveyed, for example, in a banknote inspection device used for an automatic depositing machine. Related to a thickness detecting device.

(Prior Art) For example, in a device such as a banknote inspection device that reads information held by each banknote that is conveyed, detecting the thickness of the banknote is also an important item. . The thickness detection device for such a purpose is for determining whether or not one banknote has been conveyed and whether it is attached to a tape or the like, and is configured as follows. ing. That is, a movable detection roller is brought into contact with a reference roller that serves as a thickness measurement reference, and a bill conveyed by a conveyor belt is passed between these rollers to detect the thickness of the passing bill. Whether the amount of displacement of the roller is converted into an electric signal by, for example, a non-contact displacement meter, and the electric signal indicates whether there is one banknote, or whether it is a banknote with a tape or the like or two or more banknotes. Is to determine.

However, in the conventional thickness detecting device configured as described above, the surface of the reference roller is at a certain distance from its rotation axis and does not vary, that is, the thickness is detected as if the reference roller has no eccentricity. Was going on. Therefore,
If the reference roller is eccentric, the thickness of the banknote determined by the thickness detection device using the reference roller does not correctly detect the actual thickness. In order to eliminate this drawback, a reference roller without eccentricity may be used, but in order to obtain a reference roller without eccentricity, the reference roller must be manufactured using an expensive material, or the reference roller It is necessary to improve the processing accuracy of
There is a problem that it causes price increase.

(Problems to be Solved by the Invention) The present invention has been made to solve the problem that the thickness of a paper sheet cannot be correctly detected when the reference roller is eccentric as described above. An object of the present invention is to provide a paper sheet thickness detection device that can correctly detect the paper sheet thickness without being affected by the degree of eccentricity of the reference roller that differs depending on the material or processing degree.

[Structure of the Invention] (Means for Solving Problems) A thickness detecting device for a paper sheet according to the present invention includes a reference roller serving as a thickness measurement reference, and a displaceable detection roller contacting the reference roller. And a conveying means for feeding a paper sheet as an object to be measured between the reference roller and the detection roller, and a displacement of the detection roller when the paper sheet is fed between the reference roller and the detection roller. Conversion means for converting the amount into an electric signal, storage means for storing eccentricity data of the reference roller with respect to a plurality of surface positions of the reference roller in advance, and position recognition means for recognizing a plurality of surface positions of the reference roller , The eccentricity data of the reference roller corresponding to the position recognized by the position recognizing means is read from the storage means, and the read output eccentricity data is used to supplement the output signal of the corresponding converting means. It is provided with a correction means for.

(Operation) In the present invention, the eccentricity data of the reference roller for a plurality of surface positions of the reference roller is stored in the storage means in advance, and the reference roller of the reference roller when the sheet is conveyed and its thickness is detected. The position of the surface is recognized by the position recognizing means, the eccentricity data corresponding to the recognized position is read from the storage means, and the read eccentricity data is used to correct the corresponding thickness detection output. It is a thing.

(Example) Hereinafter, one example of the present invention will be described with reference to the drawings. In FIG. 2, reference numeral 1 is a reference roller that serves as a reference for measurement, 2 is a displaceable detection roller that contacts the reference roller 1, 3 is a converter that converts the displacement amount of the detection roller 2 into an electric signal, and 4 is a target. Banknotes 5 which are objects to be measured are conveyor belts for nipping and conveying the banknote 4.

When the bill 4 sandwiched between the reference roller 1 and the detection roller 2 by the conveyance belt 5 is conveyed in the direction of the arrow in the figure, the detection roller 2 moves up and down according to the thickness of the bill 4, and the converter 3 moves. A voltage corresponding to the movement amount of the detection roller 2 is output.

Further, 6 is a roller positioning member attached to the reference roller 1, and 7 is an optical timing sensor (detector) composed of a light emitting element and a light receiving element. The position of the reference roller 1 is recognized by detecting "dark" output at a rate of once.

Now, in this device, an adhesive tape 8 as shown in FIG.
It is assumed that the banknote 4 attached with is conveyed. Here, the thickness of the banknote 4 is 80 μm, the thickness of the adhesive tape 8 is 40 μm, and the circumference of the reference roller 1 is 50 μm as shown in FIG.
If it is divided into equal parts, as shown in FIG. 5 (a), when the reference roller 1 has no eccentricity, when the α point of the bill 4 passes, the output of the converter 3 indicates 120 microns, and this position is the roller. It corresponds to the x section from the position where the timing sensor 7 detects "dark" by the positioning member 6. Similarly, when the β point of the bill 4 passes, the output of the converter 3 is 12
It shows 0 micron, which corresponds to the y section. That is, assuming that the cross section of the banknote 4 is AB and the reference roller 1 is not eccentric, the output of the converter 3 has the waveform shown in FIG. Here, in order to detect a portion where the banknote 4 is thicker than usual, an excessively thick determination level is introduced, and if this level is set to 100 microns, the excessively thick region is recognized as a shaded portion in FIG. 5 (a). To be done.

On the other hand, when the reference roller 1 is eccentric, as shown in FIG. 5B, the output of the converter 3 is zero on the reference surface (the surface of the reference roller 1 without eccentricity) in the section x. Then, 10 micron is added to the reference plane to show 130 micron. Similarly, in the section y, 40 micron is subtracted from the reference plane to show 80 micron. Therefore, a region exceeding the overthickness determination level is recognized as a shaded portion. That is, even if the thicknesses of the bill 4 and the adhesive tape 8 are constant, the position (section) where the bill 4 contacts the reference roller 1
Therefore, the output of the converter 3 has a different value, and therefore the thickness of the bill 4 is erroneously detected as it is.

FIG. 1 is a configuration diagram of an electric circuit of the present embodiment, 9 is an amplifier for amplifying an output signal of the converter 3, 10 is an A / D converter for converting an analog signal output by the amplifier 9 into a digital signal, 11 is a counter that counts the digital signal output of the A / D converter 10 and holds the displacement amount of the detection roller 2 as a digital value, and 12 is the surface position of the reference roller 1 that receives the "dark" detection signal of the timing sensor 7. With the counter
A control unit for recognizing the displacement amount of the detection roller 2 by obtaining the output value of 11, and a storage unit 13 for storing the eccentricity data of the reference roller 1.

Next, the operation of the above configuration will be described. First, in order to set the correction value (eccentricity data) for each section of the reference roller 1, the reference roller 1 is driven without transporting the banknote 4. At this time, the control unit 12 recognizes the position of the roller positioning member 6 attached to the reference roller 1 by the timing sensor 7 as the section 0, and performs section recognition (position recognition) in which the circumference is divided into 50 parts. On the other hand, the voltage value output from the converter 3 in each section is amplified by the amplifier 9, and then the analog signal is converted into a digital signal by the A / D converter 10. Next, the converted digital signal is counted by the counter 11 as a signal corresponding to one section of the reference roller 1. The content of the counter 11 is sent to the control unit 12, and the control unit 12 uses the count value of each one section as the reference roller 1.
Is compared with the count value when there is no eccentricity, that is, the value of the reference surface, and the difference is stored in the storage unit 13 as a correction value.
For example, assuming that the section from the roller positioning member 6 is x and the output of the converter 3 is 10, as a result of comparison with the value of the reference surface, if [value of the reference surface <10], the correction value of the section x is -10 microns. Becomes Further, as a result of comparison with the value of the reference surface when the reference roller 1 is in the section y, if [value of the reference surface> 40], the correction value of the section y is +40 microns, and these values are stored in the storage unit 13, respectively. Remembered. In this way, the correction value for each section of the reference roller 1, that is, the eccentricity data is stored in the storage unit 13.

Next, when the bill 4 shown in FIG. 3 is conveyed, the thickness is detected by the converter 3, and the output of the converter 3 is cut by one section and input to the control unit 12 by the same process. At this time, when the control unit 12 determines that the section from the position of the roller positioning member 6 is x, the correction value corresponding to the section x, that is, the value of −10 microns is read from the storage unit 13 and converted. Output count value of device 3 to 130 microns -10
It is assumed that a thickness of 120 microns is detected by correcting only a micron. Similarly, when the control unit 12 determines that the section is y, a correction value corresponding to the section y, that is, a value of +40 microns is read from the storage unit 13, and the output count value of the converter 3 is set to 80 microns to +40 microns. It is assumed that a thickness of 120 microns is detected by correcting only a micron. Thereafter, when the correction is performed on the entire section of the reference roller 1 in the same manner, the output waveform of the corrected converter 3 as shown in FIG. 5C is obtained. This is the same as the waveform when the reference roller 1 shown in FIG. 5A has no eccentricity, and the thickness of the bill 4 can be correctly detected.

In addition, in the said Example, although the paper sheet which performs thickness detection demonstrated the case where it is a banknote, this invention is not limited to this, For example, in the case of securities other than banknotes or mail, it is the same. Applicable to

[Effects of the Invention] As described in detail above, according to the paper sheet thickness detection apparatus of the present invention, the eccentricity of the reference roller is measured and stored in advance, and the paper sheet thickness is actually measured. Since the correction is performed by referring to the stored value when performing, the correct result can be obtained even if the reference roller is eccentric. Further, it is not necessary to use an expensive material in order to obtain the reference roller having no eccentricity, and the processing accuracy is only required to be at a certain level, so that the price increase can be controlled.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a configuration diagram of an electric circuit, FIG. 2 is a configuration diagram of a thickness detection device, and FIG. 3 is an explanatory diagram showing a state of bills to be conveyed. FIG. 4 is an explanatory diagram showing division of the reference roller, FIG. 5 is an output waveform diagram of the converter, FIG. 5A is a waveform diagram when the reference roller has no eccentricity, and FIG. A waveform diagram when the reference roller has eccentricity, and FIG. 7C is a waveform diagram after the eccentricity is corrected. 1 ... Reference roller, 2 ... Detection roller, 3 ... Converter,
4 ... Banknotes (paper sheets), 5 ... Conveyor belt, 6 ... Roller positioning member, 7 ... Timing sensor (detector),
8 ... Adhesive tape, 9 ... Amplifier, 10 ... A / D converter, 1
1 …… Counter, 12 …… Control section, 13 …… Storage section.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Motota Yamada 70 Yanagi-cho, Sachi-ku, Kawasaki City, Kanagawa Prefecture, Toshiba Automatic Equipment Engineering Co., Ltd. (56) References JP-A-60-140118 (JP, A) JP-A-60 -169990 (JP, A) Actual opening Sho 56-37002 (JP, U) Actual opening Sho 61-143009 (JP, U)

Claims (3)

[Claims] 1. A reference roller serving as a thickness measurement reference, a displaceable detection roller in contact with the reference roller, and a conveyance for feeding a sheet to be measured between the reference roller and the detection roller. Means, a conversion means for converting the displacement amount of the detection roller when a sheet is fed between the reference roller and the detection roller into an electric signal, and the reference for a plurality of surface positions of the reference roller in advance. Storage means for storing roller eccentricity data, position recognition means for recognizing a plurality of surface positions of the reference roller, and eccentricity data for the reference roller corresponding to the position recognized by the position recognition means. And a correcting means for correcting the output signal of the corresponding converting means by using the read eccentricity data. 2. The position recognizing means includes a roller positioning member attached to the reference roller and a detector for detecting the roller positioning member, and a plurality of the reference rollers are detected based on outputs of the detector. The sheet thickness detecting device according to claim 1, wherein the surface position is recognized. 3. The paper sheet thickness detecting device according to claim 1, wherein the paper sheets are banknotes.