JP2017207991A - Medium identification device, medium identification method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a medium identification device and a medium identification method capable of accurately detecting coins without reducing reception performance.SOLUTION: The medium identification device includes: a magnetic medium detect means 4 that determines existence/non-existence of medium depending on the level of a magnetic sensor; and an optical medium detect means 5 that, when the magnetic medium detect means detects existence of medium, detect and outputs arrival of the medium by an optical sensor. With this, when a foreign matter of non-magnetic medium is transported following a coin, the medium identification device performs a series of image processing of desired coins only.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a medium identification device and a medium identification method.

  As a medium detection means for imaging a coin, there is a method using a photoelectric sensor. For example, in Patent Document 1, the arrival of the coin 2 is detected by monitoring whether or not the coin 2 transported on the transport path 1 blocks the light projected from the projector 11Aa.

  In addition, there is a method of using a magnetic sensor as a medium detection means for imaging a coin. For example, in Patent Document 2, when it is detected that the coin C has passed through the magnetic sensor 2, the denomination of the coin C is identified based on the peak level of the output signal, and the light 13 is emitted from the light source 12 at the irradiation timing. The authenticity of the coin C is determined based on the image of the surface of the coin C.

JP 2009-276951 A JP 2003-317127 A

  Patent Document 1 describes a method of using a photoelectric sensor as medium detection means for imaging a coin. When the medium is detected only by the photoelectric sensor, an image is taken even if a non-magnetic medium other than the coin that is originally intended to be handled is currency. Since the captured image is two-dimensional data, the amount of data is larger than that of magnetic one-dimensional data, and the transfer time from the sensor to the image storage means (memory) and the processing time of the image are greatly increased. For this reason, if a non-magnetic medium is mistakenly imaged, until the image processing is completed, the next medium that the user originally wants to handle cannot be imaged and processed, so that the acceptance cannot be determined, and the coin acceptance performance deteriorates. .

  Patent Document 2 describes a method of using a magnetic sensor as a medium detection means for imaging a coin. When the medium is detected only by the magnetic sensor, the medium detection position accuracy is lower than that of the photoelectric sensor, so that the imaging visual field range needs to be made larger than the coin to be originally handled. As a result, there is a problem in that the means for imaging increases, and the image transfer time and image processing time increase. Further, since it is premised that the denomination can be discriminated by magnetism, a means capable of discriminating the denomination by magnetism is required before imaging, and there is a problem that coins that cannot be denominated by magnetism cannot be handled.

  The present invention has been made in view of the above, and an object of the present invention is to provide a medium identifying device and a medium identifying method capable of accurately detecting coins without deteriorating reception performance.

  In order to solve the above-described problems and achieve the object, a medium identification device according to the present invention includes a magnetic medium detection unit that determines the presence or absence of a medium according to the level of a magnetic sensor, and the magnetic medium detection unit includes a medium. An optical medium detection unit that detects the arrival of the medium by an optical sensor when detected, and is configured as a medium identification device.

  The present invention is also grasped as a medium identification method performed by the medium identification device.

  According to the present invention, it is possible to accurately detect coins without deteriorating reception performance.

The side view showing the state at the time of imaging a coin. The figure seen from the top when imaging a coin. The change figure of a magnetic sensor level when the coin 2 passes the magnetic-medium detection means 4. FIG. The functional block diagram of an Example. Explanatory drawing when seeking the center of a coin. The figure which plotted the average of the ring-shaped brightness on the basis of the center. The figure which plotted the average of the brightness of a ring-shaped area for every radius. The figure seen from the top when a subsequent coin comes behind the image processing of a preceding coin. The figure seen from the top when a succeeding coin comes during image processing of a preceding foreign material.

  Embodiments of a medium identification device and a medium identification method according to the present invention will be described below in detail with reference to the accompanying drawings. In the example shown below, an example in which the medium identifying device identifies Japanese yen coins is shown. However, the present invention is not particularly limited to this, and can be applied to various media such as foreign coins and medals.

  1 and 2 show the configuration of a coin discriminating apparatus to which a medium discriminating apparatus and a medium discriminating method according to the present invention are applied. FIG. 1 is a side view of the coin identification device, and FIG. 2 is a view of the coin identification device as viewed from above. Coins 2 are transported in the transport direction 3 on the transport path 1. The medium detection means includes a magnetic medium detection means 4 and an optical medium detection means 5 located downstream of the magnetic medium detection means 4, and the optical medium detection means 5 further includes a projector 5a and a light receiver 5b. ing.

  When there is no coin, the light projected from the projector 5a is received by the light receiver 5b. However, when the coin 2 is conveyed, the projected light is blocked by the coin 2 and is not received by the light receiver 5b. In the coin identification device according to the present embodiment, the arrival of the target coin 2 can be accurately detected by monitoring the light receiver 5b only when the presence of a coin is detected by the magnetic medium detection means 4 described below. Can do.

In FIG. 3, when the time axis 31 is taken on the horizontal axis and the magnetic sensor level output from the magnetic medium detecting means 4 is taken as the magnetic sensor level axis 32, the coin 2 passes through the magnetic medium detecting means 4. It is the figure which plotted a state of going. In FIG. 3, the transition is shown as a magnetic sensor level waveform 33. As shown in FIG.
When the coin 2 is away from the magnetic medium detection unit 4, the magnetic sensor level is low, but the magnetic sensor level increases as the coin 2 approaches the magnetic medium detection unit 4. While the coin 2 passes over the magnetic medium detection means 4, the state close to the peak continues, and the original magnetic sensor level becomes lower as the coin 2 moves away from the magnetic medium detection means 4.
The magnetic medium detection unit 4 determines that there is a coin when the value of the plot is equal to or greater than the threshold 34 with magnetism, and determines that there is no coin when the value is less than the threshold 34 with magnetism. It can be determined whether or not there is a coin. Since the magnetic sensor level of coins is very high, by increasing the threshold 34 with magnetism to some extent, a magnetic medium having a small magnetic sensor level is handled as a non-magnetic medium (foreign matter) so that no image is taken. You can also.

  In addition, when the coin identification device discriminates the denomination of the coin, the accuracy of the magnetic sensor itself is required to separate similar magnetic sensor levels. Further, in order to secure the sensitivity of the magnetic sensor, the device for shortening the distance between the magnetic medium detecting means 4 and the coin 2 and the coin 2 for suppressing fluctuations in the magnetic sensor level due to the distance characteristics of the magnetic medium detecting means 4 and the coin 2 Ingenuity such as suppression of fluttering of its own is required, but an inexpensive method without such ingenuity can be achieved as compared with the case where the denomination is discriminated only for the presence / absence of magnetism. When the arrival of the coin 2 is detected by the magnetic medium detecting means 4 and the optical medium detecting means 5, light is emitted from the light emitting means 6 of FIG. 1 toward the coin 2. The reflected light from the surface of the coin 2 can be imaged by reaching the imaging means 7 arranged on the upstream side of the optical medium detection means 5. When the arrival of the coin 2 is detected, the magnetic medium detection means 4 determines that the plot value is equal to or greater than the threshold value 34 with magnetism, and the light is projected from the projector 5 a constituting the optical medium detection means 5. This is a case where light is blocked and is not received by the light receiver 5b.

  FIG. 4 is a functional block diagram of the coin identifying device in the present embodiment. When the coin 2 is transported on the transport path 1, the magnetic medium detection means 4 first detects the presence of a coin (S1), and then the optical medium detection means 5 detects the leading edge of the coin 2 with high accuracy (S2). The medium detection means 41 detects the moment when the coin arrives (S3), and notifies the light emission control means 42 and the imaging control means 43 (S4). The light emission control means 42 controls the light emission means 6 to emit light (S5). The light projected from the light emitting means 6 onto the surface of the coin 2 is reflected by the surface of the coin 2 and reaches the imaging means 7.

  The imaging control unit 43 that has received the notification from the medium detection unit 41 in S4 controls the imaging unit 7 to perform imaging (S6, S7). The image of the surface of the coin 2 obtained by the imaging means 7 is transferred to and stored in the image storage means 45 (S8). The discrimination means 46 compares the image of the surface of the coin 2 stored in the image storage means 45 with the template of the surface of each denomination stored in advance in the reference data storage means 44, thereby denomination and It is determined whether or not the denomination is accepted by making a true / false determination (S9).

  The details of denomination and true / false discrimination will be explained. The discriminating means 46 obtains the center C of the coin 51 as shown in FIG. 5 for the image of the surface of the coin 2 stored in the image storage means 45. As an embodiment, the intersections A1 and A2 with the coin 51 are obtained on a straight line in the X direction, and the X coordinate of the midpoint AC is set as the X coordinate of the center C. Further, intersections B1 and B2 with the coin 51 are obtained on a straight line in the Y direction, and the Y coordinate of the center point BC is set as the Y coordinate of the center C. As another embodiment, AC and BC may be obtained for each line in both the X direction and the Y direction, and the center C may be obtained using the average.

  When the center C is obtained as shown in FIG. 5, the discriminating means 46 obtains the average of the brightness of the image for each ring-shaped area 61 at the same distance from the center C as shown in FIG. In FIG. 6, it can be seen that the coin 51 is divided into three ring-shaped areas. When the average brightness level is plotted for each distance r, it is as shown in FIG. In the reference data storage means 44, templates serving as reference data corresponding to FIG. 7 are stored in advance for the front surfaces (front / back) of each denomination. The discriminating means 46 performs template matching between the average brightness for each ring derived from the surface image of the coin 2 stored in the image storage means 45 and the reference data stored in the reference data storage means 44. The denomination is confirmed by comparison. If the similarity is less than the specified value as a result of template matching, the determination unit 46 determines that there is no denomination. By detecting in this way, even if there is a nonmagnetic medium (foreign matter) before the coin, the next coin can be imaged without imaging the nonmagnetic medium (foreign matter). Here, the difference between the case where the medium is detected only by the optical medium detecting means 5 and the effect will be described in detail with reference to FIGS.

  FIG. 8 is a view seen from above like FIG. 2, and the preceding coin 81 and the succeeding coin 82 are conveyed in the direction of the conveyance direction 3 on the conveyance path 1. When the optical medium detection means 5 detects the preceding coin 81, the processing up to the discrimination means 46 is performed by the method described above, and this series of processing is called image processing. By multiplying the time required for the image processing by the conveyance speed, the time required for the image processing can be converted into a distance, and this distance is referred to as an image processing distance 83.

  The succeeding coin 82 is transported in such a state that the coin interval is widened so as to be transported after the image processing distance 83 of the preceding coin 81. For example, by combining belts having different conveyance speeds (not shown in FIG. 8) and arranging a belt having a high conveyance speed next to a belt having a low conveyance speed, the coin interval can be widened due to the difference in conveyance speed. . In this case, the same result can be obtained by the method according to the present embodiment or the detection by the optical medium detection means 5 alone.

  FIG. 9 is a view of the coin discriminating apparatus as seen from above, as in FIG. 2, in which the nonmagnetic medium (foreign matter) 91 precedes the transport path 1 and the coin 2 is transported in the transport direction 3 thereafter. . For the coins to be handled, the preceding coin and the succeeding coin can be separated by the above-described method or the like. For example, an unexpected foreign object that cannot be detected by the optical medium detecting means 5 cannot be sufficiently separated. The subsequent coin 82 may be conveyed within the image processing distance 83 of the foreign object 91.

  In this case, when the detection is performed only by the optical medium detection unit 5, the subsequent coin 82 reaches the optical medium detection unit 5 during the image processing of the preceding foreign material 91, so that the image processing of the subsequent coin 82 cannot be performed and the reception performance is reduced. It becomes. In the case of the method according to the present embodiment, since the preceding foreign matter 91 is not detected by the magnetic medium detecting means 4, image processing (for example, the processing after S7 shown in FIG. 4) is performed on the preceding foreign matter 91. The image processing of the succeeding coin 82 can be performed without executing it, and the deterioration of the reception performance can be prevented.

  In this embodiment, the imaging unit is arranged on the upper side and the magnetic medium detection unit is arranged on the lower side. However, the imaging unit may be arranged in any way, and the magnetic medium detection unit does not interfere with the imaging unit. What is necessary is just to be able to arrange.

  In this embodiment, the optical medium detection means 5 and the magnetic medium detection means 4 are arranged close to each other, and medium detection is performed at the timing when the medium is detected by the optical medium detection means while the medium is detected magnetically. However, the magnetic medium detection unit may be disposed at a distance sufficiently further upstream than the optical medium detection unit 5 on the upstream side in the transport direction, for example, further on the reverse transport direction side than the imaging unit. In this case, it may be considered that the magnetic medium detection unit 4 detects the presence of the medium and then detects it after the conveyance distance between the magnetic medium detection unit 4 and the optical medium detection unit 5. That is, the discriminating means 46 detects the arrival of the medium when the magnetism detecting means 4 detects the presence of the medium, and the optical detecting means 5 detects the medium after the passage of time or distance determined based on the medium conveyance speed. It may be considered that the arrival of is detected. This transport distance may be obtained by multiplying the transport speed by time or from a pulse count obtained from a rotary encoder.

  In the present embodiment, the transmission type example in which the projector and the light receiver are arranged to oppose each other as the optical medium detection means 5 is described. However, any photoelectric sensor using light with high directivity may be used. A reflection type arranged on the same side may be used.

  In the present embodiment, a foreign medium is handled as a non-magnetic medium for a coin that is a magnetic medium, and a case where a coin is detected with a magnetism threshold value of 34 or more and an optical medium is detected during this period is described. A magnetic medium may be used as a target, and foreign matter may be used as a magnetic medium, and a magnetic non-magnetic medium having a magnetism less than the threshold 34 may be imaged during this period.

  As described above, in this embodiment, as a medium detection unit for capturing an image of a coin, only when the presence of a coin is detected by a magnetic sensor, the position of the coin is accurately detected by accurately detecting the position of the medium by the photoelectric sensor. Can be detected well. Conventionally, there is a method of detecting with a photoelectric sensor in order to accurately measure the timing of imaging a target coin in coin identification, but by deviating the timing of imaging a coin originally intended to be imaged by imaging a non-target foreign object. There was a problem that reception performance deteriorated. However, according to the present embodiment, since the medium can be accurately detected for the originally intended coin, the image transfer time range and the image processing time can be originally handled by making the imaging field of view range the size of the originally desired coin. It is possible to suppress the increase in each processing time, and it is possible to suppress a decrease in reception performance even when a non-magnetic medium (foreign matter) passes. In addition, since it is not necessary to discriminate the denomination in advance, it is not always necessary to discriminate the denomination by magnetism before imaging, and it is possible to accurately detect and image even a coin that cannot be discriminated by magnetism. .

DESCRIPTION OF SYMBOLS 1 ... Conveyance path, 2 ... Coin, 3 ... Conveying direction, 4 ... Magnetic medium detection means, 5 ... Optical medium detection means, 5a ... Light projector, 5b ... Light receiver, 6 ... Light emission means, 7 ... Imaging means, 31 ... Time Axis 32: Magnetic sensor level axis 33 ... Magnetic sensor level waveform 34 ... Magnetic threshold value 41 ... Media detection means 42 ... Light emission control means 43 ... Imaging control means 44 ... Reference data storage means 45 ... Image Storage means 46... Discriminating means 81. Preceding coin 82. Subsequent coin 83 83 Image processing distance 91 Nonmagnetic medium (foreign matter)

Claims (5)

Magnetic medium detection means for determining the presence or absence of a medium according to the level of the magnetic sensor;
An optical medium detection means for detecting the arrival of the medium by an optical sensor when the magnetic medium detection means detects the presence of the medium;
A medium identification device comprising: An imaging unit that is disposed upstream of the optical medium detection unit and that images the medium detected by the magnetic medium detection unit as being present;
Discrimination means for executing image processing on the medium imaged by the imaging means, and discriminating the medium based on an image obtained by the image processing;
The medium identification device according to claim 1, further comprising: The magnetic detection means is disposed further upstream than the imaging means,
The discriminating unit detects the arrival of the medium when the magnetic detection unit detects the presence of the medium, and the optical detection unit detects the arrival of the medium after a lapse of time determined based on the conveyance speed of the medium. Is detected,
The medium identification apparatus according to claim 2, wherein A magnetic medium detection step in which the magnetic medium detection means determines the presence or absence of the medium according to the level of the magnetic sensor;
An optical medium detection step in which the optical medium detection means detects the arrival of the medium by an optical sensor when the presence of the medium is detected by the magnetic medium detection step;
A medium identification method comprising: An imaging step in which an imaging unit disposed on the upstream side of the optical sensor images the medium detected as having a medium in the magnetic medium detection step;
A discriminating step, wherein a discriminating unit executes image processing on the medium imaged in the imaging step, and discriminates the medium based on an image obtained by the image processing;
The medium identification method according to claim 4, further comprising:

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