Deformed coin determination device, coin discriminator, coin processor, and deformed coin determination method

Abstract

To provide a deformed coin determination device, a coin identification machine, a coin processing machine, and a deformed coin determination method that enable even a slightly deformed coin to be detected as a deformed coin at a high accuracy.SOLUTION: The deformed coin determination device includes: radius calculation means for calculating, from an image of a coin, a plurality of radii of the coin; reference radius calculation means for calculating a reference radius of the coin from the image; first feature quantity calculation means for calculating a first feature quantity representing variations in data on the plurality of radii based on the plurality of radii with respect to data on the reference radius based on the reference radius; and deformed coin determination means for determining whether or not the coin is a deformed coin based on the first feature quantity.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a deformed coin determination device, a coin discriminator, a coin processor, and a deformed coin determination method. [Background technology]

[0002] Conventionally, a deformed coin discrimination method has been known in which an image of a coin is captured by a camera, the deformation level of the coin is determined based on the captured image, and whether or not the coin is a deformed coin is determined based on the determined deformation level.

[0003] For example, Patent Document 1 discloses a deformed coin discrimination method that is applied to a coin processing device that detects deformed coins, and that includes an image acquisition step of acquiring an image of the coin, a center setting step of setting the center of the coin based on the characteristics of the image acquired by the image acquisition step, a polar coordinate image acquisition step of acquiring an image that has been polar coordinate converted from the center of the coin set by the center setting step, an identification step of identifying the denomination of the coin based on the characteristics of the image acquired by the polar coordinate image acquisition step, a defect amount detection step of detecting the amount of defect in the orbit of the outer periphery of the coin based on the image acquired by the polar coordinate image acquisition step, and a discrimination step of determining whether the coin is deformed based on the amount of defect detected by the defect amount detection step and a threshold value that is pre-stored for each denomination of the coin identified by the discrimination step, and a coin processing device that executes the deformed coin discrimination method. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5572450 Summary of the Invention [Problem to be solved by the invention]

[0005] The method described in Patent Document 1 obtains the amount of loss along the periphery, so it is possible to detect deformation when the periphery of the coin is partially deformed significantly. However, in the case of minute deformation (for example, deformation in an elliptical shape), the amount of loss is small, so there is a problem that the detection accuracy is not high. One method to detect such minute deformations is to narrow the threshold range, but this creates the problem of false detection being more likely to occur if there is noise due to dust, mechanical parts, etc. Therefore, it has been difficult to improve detection accuracy by adjusting the threshold range.

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and the purpose of the present disclosure is to provide a deformed coin determination device, coin identification machine, coin processing machine, and deformed coin determination method that can detect even slightly deformed coins as deformed coins with high accuracy. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems and achieve the objectives, (1) a deformed coin determination device according to a first aspect of the present disclosure comprises a radius calculation means for calculating multiple radii of the coin from an image of the coin, a reference radius calculation means for calculating a reference radius of the coin from the image, a first feature calculation means for calculating a first feature representing the variation of multiple radius data based on the multiple radii relative to reference radius data based on the reference radius, and a deformed coin determination means for determining whether the coin is a deformed coin based on the first feature.

[0008] (2) In the deformed coin determination device described in (1) above, the radius calculation means may calculate the multiple radii so that the points for obtaining the multiple radii are positioned at predetermined intervals on the outer periphery of the coin.

[0009] (3) In the deformed coin determination device described in (1) or (2) above, the variation of the multiple radius data relative to the reference radius data may be the variation of the difference between the reference radius data and the multiple radius data, or the variation of the ratio of the multiple radius data to the reference radius data.

[0010] (4) In the deformed coin detection device described in any one of (1) to (3) above, the first feature amount may be a value calculated by the following formula (1).

[0011]

number

[0012] (5) In the deformed coin determination device described in any one of (1) to (4) above, the first feature calculation means may group the multiple radii into groups of p adjacent radii (where p is a natural number greater than or equal to 2), calculate a sum based on the p radii for each group as the multiple radius data, and calculate the first feature based on the sum.

[0013] (6) In the deformed coin determination device described in (5) above, the first feature calculation means may calculate, as the reference radius data, the product of the number of radii used to calculate the total value and the reference radius for each group.

[0014] (7) The deformed coin determination device described in any of (1) to (6) above may further include a second feature calculation means for calculating a second feature representing the variation of multiple diameters calculated from the image relative to a reference diameter calculated from the image, and the deformed coin determination means may determine whether the coin is a deformed coin based on the first feature and the second feature.

[0015] (8) In the deformed coin detection device described in (7) above, the variation of the multiple diameters relative to the reference diameter may be the variation of the difference between the reference diameter and the multiple diameters, or the variation of the ratio of the multiple diameters to the reference diameter.

[0016] (9) In the deformed coin detection device described in (7) or (8) above, the second feature amount may be a value calculated by the following formula (2).

[0017]

number

[0018] (10) The deformed coin determination device described in any of (7) to (9) above may further include a third feature calculation means for calculating a third feature based on the first feature and the second feature, and the deformed coin determination means may determine whether the coin is a deformed coin based on the third feature.

[0019] (11) In the deformed coin detection device described in (10) above, the third feature amount may be a product of the first feature amount and the second feature amount.

[0020] (12) A coin validator according to a second aspect of the present disclosure is equipped with the deformed coin determination device described in (1) or (2).

[0021] (13) A coin processing machine according to a third aspect of the present disclosure includes the coin validator described in (12).

[0022] (14) Furthermore, a deformed coin determination method according to a fourth aspect of the present disclosure includes a radius calculation step of calculating multiple radii of the coin from an image of the coin, a reference radius calculation step of calculating a reference radius of the coin from the image, a first feature calculation step of calculating a first feature representing the variation of multiple radius data based on the multiple radii relative to reference radius data based on the reference radius, and a deformed coin determination step of determining whether the coin is a deformed coin based on the first feature. [Effects of the Invention]

[0023] According to the present disclosure, it is possible to provide a deformed coin determination device, coin identification machine, coin processing machine, and deformed coin determination method that can detect even slightly deformed coins as deformed coins with high accuracy. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 is a block diagram illustrating the configuration of a deformed coin detection device according to the first embodiment. [Figure 2] FIG. 2 is a flowchart illustrating an example of the operation of the deformed coin detection device according to the first embodiment. [Figure 3A] FIG. 3A is an explanatory diagram schematically illustrating an example of a method in which the radius calculation means calculates a plurality of radii of a coin from an image of the coin in the deformed coin determination device according to the first embodiment of the present disclosure. [Figure 3B] FIG. 3B is an explanatory diagram schematically illustrating an example of a method in which the radius calculation means calculates a plurality of radii of a coin from an image of the coin in the deformed coin determination device according to the first embodiment of the present disclosure. [Figure 4] FIG. 4 is an explanatory diagram schematically illustrating an example of a method in which the reference radius calculation means calculates the reference radius of a coin from an image of the coin in the deformed coin detection device according to the first embodiment of the present disclosure. [Figure 5] FIG. 5 is an explanatory diagram schematically showing an example of a method for calculating radius data and reference radius data in a deformed coin determination device according to a modified example of the first embodiment. [Figure 6] FIG. 6 is a block diagram illustrating the configuration of a deformed coin determination device according to the second embodiment. [Figure 7] FIG. 7 is a flowchart illustrating an example of the operation of the deformed coin detection device according to the second embodiment. [Figure 8] FIG. 8 is an explanatory diagram schematically illustrating an example of a method in which the second feature amount calculation means calculates the diameter in the deformed coin determination device according to the second embodiment of the present disclosure. [Figure 9] FIG. 9 is a block diagram illustrating the configuration of a deformed coin determination device according to Modification 1 of Embodiment 2. As shown in FIG. [Figure 10]FIG. 10 is a block diagram illustrating the configuration of a deformed coin determination device according to Modification 2 of Embodiment 2. As shown in FIG. [Figure 11] FIG. 11 is a flowchart illustrating an example of the operation of the deformed coin determination device according to the second modification of the second embodiment. [Figure 12] FIG. 12 is an explanatory diagram schematically illustrating an example of a method in which the radius calculation means calculates a plurality of radii of a coin from an image of the coin in the deformed coin determination device according to Modification 2 of Embodiment 2 of the present disclosure. [Figure 13] FIG. 13 is a block diagram illustrating the configuration of the coin validator of the present disclosure. [Figure 14] FIG. 14 is a diagram illustrating an example of threshold information. [Figure 15] FIG. 15 is a side cross-sectional view that schematically illustrates an example of a coin processing machine according to the present disclosure. [Figure 16] FIG. 16 is a flowchart illustrating an example of the operation of the coin processing machine of the present disclosure.

[0025] Hereinafter, embodiments of a deformed coin determination device and a deformed coin determination method according to the present disclosure will be described in detail.

[0026] In the following description, the same reference numerals are used in common between different drawings to designate the same parts or parts having similar functions, and repeated explanations thereof will be omitted. In addition, the drawings explaining the structure show XYZ coordinate systems that are orthogonal to each other as appropriate.

[0027] (Embodiment 1) The deformed coin determination device according to a first embodiment of the present disclosure comprises a radius calculation means for calculating multiple radii of the coin from an image of the coin, a reference radius calculation means for calculating a reference radius of the coin from the image, a first feature calculation means for calculating a first feature representing the variation of multiple radius data based on the multiple radii relative to reference radius data based on the reference radius, and a deformed coin determination means for determining whether the coin is a deformed coin based on the first feature.

[0028] The principle by which a deformed coin can be detected in the deformed coin detection device according to the first embodiment of the present disclosure will be described. If the outline of a coin is a perfect circle when viewed in plan, the distance from the center of the coin to the outer periphery of the coin (i.e., the radius) is constant regardless of the outer periphery. However, when a coin is deformed, the outline of the coin when viewed in plan is distorted and it is no longer a perfect circle, so the distance from the center of the coin to its periphery changes depending on the position of the periphery. In other words, the distance from the center of the coin to its periphery is not constant but varies. Conversely, if there is a large variation in the distance from the center of the coin to the outer periphery of the coin, there is a high possibility that the coin is deformed. Therefore, by calculating the variation of multiple radii of the coin relative to the reference radius of the coin as one feature, it is possible to determine with high accuracy whether the coin is deformed. Furthermore, the variation in not only the radius and reference radius themselves but also parameters calculated from the radius and reference radius (for example, the sum of multiple radii or an integer multiple of the reference radius) can reflect the variation in radius. Therefore, the deformed coin determination device disclosed herein can determine with high accuracy whether the coin is deformed by calculating the variation of multiple radius data based on multiple radii relative to reference radius data based on a reference radius as the first feature. Such a deformed coin discriminating device will be described below with reference to the drawings.

[0029] FIG. 1 is a block diagram illustrating the configuration of a deformed coin detection device according to the first embodiment. As shown in FIG. 1, the deformed coin detection device 10 includes a radius calculation means 11, a reference radius calculation means 12, a first feature amount calculation means 13, and a deformed coin detection means 14. The radius calculation means 11, the reference radius calculation means 12, the first feature calculation means 13, and the deformed coin determination means 14 may be incorporated into an electronic computer and function by executing a program in a controller (processor) such as a CPU.

[0030] Next, the operation of the deformed coin detection device according to the first embodiment will be described with reference to FIG. FIG. 2 is a flowchart illustrating an example of the operation of the deformed coin detection device according to the first embodiment.

[0031] As shown in FIG. 2, in the deformed coin determination device 10, first, the radius calculation means 11 calculates a plurality of radii of the coin from an image of the coin (step S11).

[0032] Next, the reference radius calculation means 12 calculates the reference radius of the coin from the image of the coin (step S12).

[0033] Next, the first feature amount calculation means 13 calculates a first feature amount that represents the variation of a plurality of radius data based on a plurality of radii with respect to reference radius data based on a reference radius (step S13).

[0034] Next, the deformed coin determination means 14 determines whether or not the coin is a deformed coin based on the first feature amount (step S14), and the operation of the deformed coin determination device 10 ends.

[0035] Each step will be described in detail below with reference to the drawings.

[0036] <Radius calculation step (step S11)> 3A and 3B are explanatory diagrams schematically illustrating an example of a method in which the radius calculation means calculates a plurality of radii of a coin from an image of the coin in the deformed coin detection device according to the first embodiment of the present disclosure. In the radius calculation step (step S11), as shown in Figure 3A, first, an image of the coin is prepared in which the center 21 of the coin 20 has been detected (note that in the following explanation, "center of the coin," "outer circumference of the coin," etc. refer to the position on the image of the coin, and do not refer to the position of the coin itself). A conventionally known method can be used to detect the center 21 of the coin 20. For example, the outer periphery 22 of the coin may be detected, and the position of the center 21 of the coin may be detected based on the trajectory of the detected outer periphery 22 of the coin.

[0037] Next, as shown in FIG. 3B, the radius calculation means 11 calculates points P (P1 to P2) on the outer periphery 22 of the coin such that the coin 20 is divided into 32 parts with the center 21 of the coin as the axis. 32 ) is detected. Then, each point P (P1 to P 32 ) to the center 21 of the coin, 32 ) is calculated as

[0038] 3B, the multiple radii r are calculated such that the points P for obtaining the multiple radii r are positioned at equal intervals on the outer periphery 22 of the coin, but in the modified coin judgment device of the present disclosure, the intervals between the points P do not have to be equal, and the multiple radii r may be calculated such that the points P are positioned at predetermined intervals on the outer periphery 22 of the coin. The "predetermined intervals" are intervals that are arbitrarily set in advance, and the radius calculation means 11 may detect the points P according to that setting. In addition, in Figure 3B, multiple radii r are obtained based on points P on the outer periphery of the coin, which divide the coin 20 into 32 parts with the coin center 21 as the axis, but in the modified coin judgment device disclosed herein, the number of divisions is not particularly limited as long as two or more radii r can be obtained.

[0039] <Reference radius calculation step (step S12)> FIG. 4 is an explanatory diagram schematically illustrating an example of a method in which the reference radius calculation means calculates the reference radius of a coin from an image of the coin in the deformed coin detection device according to the first embodiment of the present disclosure. As shown in FIG. 4, in (Step S12), the reference radius calculation means 12 calculates the radius of each point P (P1 to P 32 ), a pair of points P is detected where the angle of the line segment connecting each point P from the center 21 of the coin is 180° (for convenience, P1 and P 17 are shown as paired points P), the distance between the paired points P (the sum of two radii calculated from the paired two points P, for example, r1 and r 17 The sum of these values ​​is calculated as the diameter R of the coin 20. Then, the calculated diameters R are sorted in order of length, and the average of the diameters R of the four central diameters is calculated to obtain the reference diameter R. s The reference diameter R s The reference radius r is 1 / 2 of the value of s It may also be possible to use the following. In the above explanation, the reference diameter R s is calculated as the average of the diameters R of the four central lines, but the reference diameter R is calculated by calculating the average of a predetermined number of central lines, for example, the two central lines. s It may also be possible to use the following.

[0040] Also, the reference radius r s The radius r of the multiple coins calculated above (step S11) may be sorted in order of length, and the average value of a predetermined number of the central radii r may be used, or the average value of all the radii r may be used.

[0041] In addition, in FIG. 4, the reference radius r is determined based on a point P on the periphery of the coin, which divides the coin 20 into 32 parts with the center 21 of the coin as the axis. s However, in the deformed coin determination device of the present disclosure, a point on the periphery of another coin different from point P for calculating radius r is used to calculate the reference radius r s may be calculated.

[0042] <First feature amount calculation step (step S13)> In step S13, the first feature amount calculation means 13 calculates the reference radius r s A first feature amount is calculated that represents a variation in a plurality of radius data based on a plurality of radii r with respect to reference radius data based on

[0043] Reference radius r s The reference radius data based on the reference radius r s It may be the reference radius r s In this way, the reference radius data may be an integer multiple of the reference radius r s The value may be based only on the

[0044] The plurality of radius data based on the plurality of radii r may be the plurality of radii r themselves, each of which may be the sum of a predetermined number of radii r, or each of which may be the average of a predetermined number of radii r. In this way, the plurality of radius data may be values ​​based only on the plurality of radii r.

[0045] The first feature value represents the variation of multiple radius data based on multiple radii r relative to reference radius data. The first feature value (variation) is zero or one if all radius data is the same as the reference radius data. In other words, when the first feature value is calculated based on the difference between the radius data and the reference radius data, the first feature value is zero if all radius data is the same as the reference radius data. When the first feature value is calculated based on the ratio between the radius data and the reference radius data, the first feature value is one if all radius data is the same as the reference radius data. When these numerical values ​​are used as a standard, the greater the variation in the radius data, the greater the deviation of the first feature value from the standard. When calculated based on the difference between the radius data and the standard radius data, the first feature value is usually a positive value, but may be a negative value. When calculated based on the ratio between the radius data and the standard radius data, the first feature value is usually a positive value. In this way, the variation of the plurality of radius data relative to the reference radius data may be either the variation of the difference between the reference radius data and the plurality of radius data, or the variation of the ratio of the plurality of radius data to the reference radius data.

[0046] The variation in the difference between the reference radius data and the plurality of radius data can be calculated, for example, by the following formula (1).

[0047]

number

[0048] In the above formula (1), the numbers assigned to the multiple radius data in order are consecutive numbers starting from 1 without overlapping among the radius data, and the maximum number is equal to the number of radius data used to calculate the first feature.

[0049] The first feature amount calculated by the above formula (1) is a value obtained by summing up the squares of the differences between the reference radius data and each radius data, and dividing the sum by the number of radius data. The reference radius data is the reference radius r s is the reference radius r s is the average value of each radius r, and each radius data is the radius r itself, the first feature amount means the variance of each radius r of the coin 20.

[0050] When the first feature value is obtained by the above formula (1), the value is large even if the deformation of the coin is slight. Therefore, by using such a first feature value, it is possible to detect deformed coins with high accuracy.

[0051] In addition, when the variation in the ratio of multiple radius data to the reference radius data is used as the variation in the variation of multiple radius data to the reference radius data, the first feature may be, for example, a value obtained by summing the ratios of each radius data to the reference radius data and dividing the sum by the number of radius data.

[0052] <Deformed coin determination step (step S14)> In (step S14), the deformed coin determination means 14 determines whether the coin 20 is a deformed coin based on the first feature amount. The standard for the determination may be such that a first threshold is set in advance, and whether or not the coin 20 is a deformed coin may be determined based on whether or not the first characteristic amount falls within the range of the first threshold. For example, if the first characteristic amount exceeds a first threshold, the coin having that first characteristic amount may be determined to be a deformed coin, and if the first characteristic amount is equal to or less than the first threshold, the coin having that first characteristic amount may be determined to be a non-deformed coin.

[0053] Various deformed coins can be detected by using the deformed coin detection device 10. In particular, V-shaped deformed coins (especially those with a small amount of curvature) can be effectively detected.

[0054] In the deformed coin determination device of the present disclosure, the order in which each step is performed is not limited as long as the radius data and reference radius data can be calculated before the <first feature amount calculation step (step S13)>.

[0055] (Modification of the first embodiment) Next, a modification of the first embodiment will be described. The deformed coin determination device of a modified example of embodiment 1 differs from the above-described deformed coin determination device 10 in that in (step S13), the first feature calculation means groups multiple radii into groups of p adjacent radii (where p is a natural number greater than or equal to 2), calculates a sum based on the p radii for each group as multiple radius data, and calculates the first feature based on the sum. In addition, in a deformed coin determination device related to a modified example of embodiment 1, the first feature calculation means may calculate, as the reference radius data, the product of the number of radii used to calculate the total value and the reference radius for each group.

[0056] A method for calculating the radius data and the reference radius data in this manner will be described below.

[0057] FIG. 5 is an explanatory diagram schematically showing an example of a method for calculating radius data and reference radius data in a deformed coin determination device according to a modified example of the first embodiment.

[0058] In the deformed coin determination device of the modified example of the first embodiment, in step S13, as shown in FIG. 5, the first feature amount calculation means classifies the radii into groups of four adjacent radii. That is, the first group G1 includes r1 to r4, the second group G2 includes r5 to r8, and the third group G3 includes r9 to r 12 The fourth group G4 contains r 13 ~r 16 The fifth group G5 includes r 17 ~r 20 The sixth group, G6, includes r 21 ~r 24 The seventh group, G7, includes r 25 ~r 28The eighth group, G8, includes r 29 ~r 32 The grouping is done so that it includes

[0059] Next, the first feature amount calculation means sums up the four radius r values ​​for each group and sets the sum as radius data. This allows eight radius data to be obtained. Also, the reference radius r s The value is multiplied by 4 to obtain the reference radius data. The first feature amount calculation means 13 may calculate the first feature amount using this radius data and the reference radius data. By calculating the first feature amount in this way, it is possible to calculate the radius data and the reference radius data for each group.

[0060] When the radius calculation means calculates multiple radii, there are cases where the image of the coin is unclear or where some radii cannot be obtained due to dust or noise on the image. In such a case, the data of that portion does not need to be used in calculating the radius data and reference radius data. In the modified deformed coin determination device of embodiment 1, radius data and reference radius data are calculated for each group, so even if one radius within a group cannot be obtained, the radius of other parts can be used to calculate the radius data and reference radius data for that group. For example, in FIG. 5, if the radius r1 of the first group G1 cannot be obtained, the radius data may be the sum of the radii r2, r3, and r4. Also, the reference radius data may be the sum of the number of radii used to calculate the radius data (i.e., 3) and the reference radius r s It may also be the product of

[0061] In Figure 5, the radii are grouped into groups of four adjacent radii, but in the modified coin determination device of embodiment 1, the number of radii r included in one group is not particularly limited as long as it is two or more.

[0062] (Method for determining deformed coins) The deformed coin determination device of the present disclosure determines whether a coin is a deformed coin by performing a radius calculation step of calculating multiple radii of the coin from an image of the coin, a reference radius calculation step of calculating a reference radius of the coin from the image, a first feature calculation step of calculating a first feature representing the variation of multiple radius data based on the multiple radii relative to reference radius data based on the reference radius, and a deformed coin determination step of determining whether the coin is a deformed coin based on the first feature. A method including these steps is also the deformed coin determination method of the present disclosure.

[0063] (Embodiment 2) The deformed coin determination device of embodiment 2 is equipped with a second feature calculation means in addition to a radius calculation means, a reference radius calculation means, a first feature calculation means, and a deformed coin determination means, and differs from the deformed coin determination device of embodiment 1 in that the deformed coin determination means determines whether a coin is a deformed coin based on the first feature and the second feature. The second feature amount means the variation of a plurality of diameters relative to a reference diameter. Such a deformed coin discriminating device will be described below with reference to the drawings.

[0064] FIG. 6 is a block diagram illustrating the configuration of a deformed coin determination device according to the second embodiment. As shown in FIG. 6, the deformed coin determination device 110 includes a radius calculation means 111, a reference radius calculation means 112, a first feature amount calculation means 113, a second feature amount calculation means 115, and a deformed coin determination means 114. The radius calculation means 111, the reference radius calculation means 112, the first feature calculation means 113, the second feature calculation means 115, and the deformed coin determination means 114 may be incorporated into an electronic computer and function by executing a program in a controller (processor) such as a CPU.

[0065] Next, the operation of the deformed coin detection device according to the second embodiment will be described with reference to FIG. FIG. 7 is a flowchart illustrating an example of the operation of the deformed coin detection device according to the second embodiment.

[0066] As shown in FIG. 7, in the deformed coin determination device 110, first, the radius calculation means 111 calculates a plurality of radii of the coin from an image of the coin (step S21).

[0067] Next, the reference radius calculation means 112 calculates the reference radius of the coin from the image of the coin (step S22).

[0068] Next, the first feature amount calculation means 113 calculates a first feature amount that represents the variation of a plurality of radius data based on a plurality of radii with respect to reference radius data based on a reference radius (step S23).

[0069] Next, the second feature amount calculation means 115 calculates a reference diameter and a diameter from the reference radius and the radius, and calculates a second feature amount that indicates the variation of the plurality of diameters relative to the reference diameter (step S24).

[0070] Next, the deformed coin determination means 114 determines whether or not the coin is a deformed coin based on the first characteristic amount and the second characteristic amount (step S25), and the operation of the deformed coin determination device 110 ends.

[0071] Each step will be described in detail below with reference to the drawings. Note that (Step S21) to (Step S23) are the same processes as (Step S11) to (Step S13) above, and therefore the explanation here will be omitted.

[0072] <Second feature amount calculation step (step S24)> <Diameter calculation substep (step S24-1)> FIG. 8 is an explanatory diagram schematically illustrating an example of a method in which the second feature amount calculation means calculates the diameter in the deformed coin determination device according to the second embodiment of the present disclosure. As shown in FIG. 8, in (Step S24), the radius calculation means 111 calculates the radius of each point P (P1 to P2) on the outer periphery 22 of the coin detected in (Step S21). 32), pairs of points P are detected where the angle of the line segment connecting each point P from the center 21 of the coin is 180°, and the distance between the paired points P (the sum of the two radii calculated from the two paired points P) is calculated as the diameter R (R1 to R 16 ) is calculated as

[0073] <Reference diameter calculation substep (step S24-2)> Next, the calculated diameters R of the coins 20 are sorted in order of length, and the average of the diameters R of the four central coins is calculated to obtain the reference diameter R. s In the above explanation, the reference diameter R s is calculated as the average of the diameters R of the four central lines, but the reference diameter R is calculated by calculating the average of a predetermined number of central lines, for example, the two central lines. s The average value of all diameters and the reference diameter R s It may also be possible to use the following.

[0074] In step S22, the reference radius r s When calculating the diameter R of the coin 20 and the reference diameter R s If the calculation is already performed, (Step S24-1) and (Step S24-2) may be omitted.

[0075] Also, the diameter R is the reference diameter R s If the value is larger than the reference diameter R, the value of the diameter R is s It is also possible to perform processing to make the value the same as The most common type of deformation in coins is bending of the main surface. When viewed from above, such a deformed coin appears elliptical. When a coin appears elliptical, the diameter of the deformed part is shorter. Furthermore, among the deformations of coins, it is rare for a part of the coin to be crushed in the thickness direction, causing the coin to protrude beyond the normal outline when viewed in plan. Therefore, the diameter R is the reference diameter R s If the value is larger than the actual value, it is highly likely that the calculated diameter R is larger than the actual value due to the influence of dust or noise on the image. If such a diameter R is used to determine whether or not the coin is deformed, it may cause a false detection. Therefore, the diameter R is the reference diameter R s If the diameter R is larger than the reference diameter R, s If the value is set to , the probability of the above-mentioned erroneous detection can be reduced.

[0076] <Second feature calculation sub-step (S24-3)> In this step, the second feature amount calculation means 115 calculates the reference diameter R s A second feature amount representing the variation of the plurality of diameters R for the

[0077] The second feature (variation) is the ratio of the total diameter R to the reference diameter R s If the second feature is the same as the diameter R, the result is zero or one. s When calculating based on the difference between the total diameter R and the reference diameter R, s If the second feature value is equal to the diameter R and the reference diameter R, the second feature value is zero. s When calculating based on the ratio of the total diameter R to the reference diameter R s If the second feature value is the same as the standard, the larger the variation in diameter R, the greater the deviation of the second feature value from the standard. Diameter R and standard R s When the second feature amount is calculated based on the difference between the diameter R and the reference diameter R, the second feature amount is usually a positive value, but may be a negative value. s When the second feature amount is calculated based on the ratio of In this way, the reference diameter R s The variation of multiple diameters R relative to the reference diameter R s and the variation in the difference between multiple diameters R and the reference diameter R s The ratio of the diameter R to the diameter R may vary.

[0078] Reference diameter R s The variation in the difference between the diameters R can be calculated, for example, by the following formula (2).

[0079]

number

[0080] In the above formula (2), the numbers assigned to the multiple diameters in order are numbers assigned consecutively from 1 without overlapping among the diameters, and the maximum number is equal to the number of diameters used to calculate the second feature.

[0081] The second feature calculated by the above formula (2) is the reference diameter R s The square of the difference between each diameter is summed up and divided by the number of diameters. Reference diameter R s is the average value of each diameter R, the second feature amount means the variance of each diameter R of the coin 20.

[0082] In addition, the reference diameter R s As the variation of multiple diameters R relative to the reference diameter R s When using the variation in the ratio of the reference diameter R to a plurality of diameters R, the second feature amount may be, for example, s Alternatively, the ratio may be calculated by adding up the ratios of each diameter R to the number of diameters R and dividing the total by the number of diameters R.

[0083] <Deformed coin determination step (step S25)> In (step S25), the deformed coin determination means 114 determines whether or not the coin 20 is a deformed coin based on the first characteristic amount and the second characteristic amount. The criteria for judgment may be to set a first threshold and a second threshold in advance, and determine whether coin 20 is a deformed coin based on whether the first characteristic amount falls within the range of the first threshold and whether the second characteristic amount falls within the range of the second threshold.

[0084] For example, if both the first characteristic amount is not within the range of the first threshold value and the second characteristic amount is not within the range of the second threshold value, the coin 20 may be determined to be a deformed coin, and if at least one of the first characteristic amount is within the range of the first threshold value and the second characteristic amount is within the range of the second threshold value, the coin 20 may be determined to be an undeformed coin. In addition, if at least one of the following conditions is met: the first characteristic amount is not within the range of the first threshold value, and the second characteristic amount is not within the range of the second threshold value, the coin 20 may be determined to be a deformed coin; and if both the first characteristic amount is within the range of the first threshold value and the second characteristic amount is within the range of the second threshold value, the coin 20 may be determined to be an undeformed coin. Such criteria can be set in advance.

[0085] In the deformed coin determination device according to the second embodiment of the present disclosure, the order in which each step is performed is not limited as long as the first feature amount and the second feature amount can be calculated before the <deformed coin determination step (step S25)>.

[0086] Here, the reason why the deformed coin detection device according to the second embodiment uses both the first feature amount and the second feature amount to determine whether or not a coin is a deformed coin will be explained.

[0087] The first feature amount represents a variation in a plurality of radius data based on a plurality of radii relative to reference radius data based on a reference radius. When calculating the first feature, if each radius is calculated based on the center of the coin, the variation of the multiple radius data from the reference radius data will be large if the coin is deformed and has a dent or bulge. In other words, the first feature is easily affected by the deformation of the coin. However, when calculating the radius of a coin, if the center of the coin is detected first, the detected center may be shifted from the true center of the coin. In this case, the variation of the multiple radius data relative to the reference radius data becomes large. In other words, the first feature is easily affected by the shift between the center of the detected coin and the true center of the coin. In other words, if there is a large variation in multiple radius data relative to the reference radius data, it may be difficult to determine whether the coin is deformed or whether the center of the detected coin is shifted from the true center of the coin based on the first feature alone.

[0088] The second feature amount represents the variation of the plurality of diameters relative to the reference diameter. When calculating the second feature amount, if each diameter is calculated from a line segment passing through the center of the coin, it is less affected even if the center of the detected coin is deviated from the center of the real coin. In other words, it can be said that the second feature amount is less affected by the deviation between the center of the detected coin and the center of the real coin.

[0089] Therefore, by using both the first and second features to determine whether or not a coin is deformed, a determination can be made that takes into account the deviation between the center of the detected coin and the center of the true coin.

[0090] In addition, if there is a dent at one end of the part where the diameter is calculated and a bulge at the other end, the diameter measured at that part may be approximately the same as the diameter measured at another part. In such a case, even though the coin is deformed, the variation of the multiple diameters relative to the reference diameter is unlikely to be large. On the other hand, even in such a case, with the first feature, the variation of the multiple radius data relative to the reference radius data will be large. In other words, it can be said that the first feature is a feature that is more susceptible to coin deformation than the second feature.

[0091] Therefore, by using both the first feature and the second feature to determine whether a coin is a deformed coin, it is possible to detect deformed coins more accurately than by using only the first feature or only the second feature.

[0092] As described above, the deformed coin detection device 110 according to the second embodiment is a deformed coin detection device that can detect deformed coins without being significantly affected by the deviation between the center of the detected coin and the center of the true coin.

[0093] (Modification 1 of Embodiment 2) Next, a first modification of the second embodiment will be described. FIG. 9 is a block diagram illustrating the configuration of a deformed coin determination device according to Modification 1 of Embodiment 2. As shown in FIG. As shown in FIG. 9, the deformed coin determination device 110a differs from the deformed coin determination device 110 in that it includes a third feature amount calculation means .

[0094] The deformed coin determination device 110a calculates a third characteristic amount based on the first characteristic amount and the second characteristic amount after (Step S24) and before (Step S25). Then, in step S25, the deformed coin determination means 114 determines whether the coin is a deformed coin based on the third feature amount. The standard for the determination may be such that a third threshold is set in advance, and whether or not the coin 20 is a deformed coin may be determined based on whether or not the third characteristic amount falls within the range of the third threshold. That is, if the third feature amount exceeds the range of the third threshold, the coin may be determined to be a deformed coin, and if the third feature amount is within the range of the third threshold, the coin may be determined to be a non-deformed coin.

[0095] The method for calculating the third feature amount is not particularly limited, but the third feature amount may be the product of the first feature amount and the second feature amount.

[0096] Here, we will take as an example a case where the first feature is a value calculated from the above formula (1), the second feature is a value calculated from the above formula (2), and the third feature is the product of the first feature and the second feature. Below, we will explain why it is possible to determine whether or not the coin is a deformed coin.

[0097] When the first feature amount is a value calculated from the above formula (1), the value increases as the variation in the plurality of radius data relative to the reference radius data increases, and decreases as the variation decreases. Furthermore, when the second feature amount is a value calculated from the above formula (2), the larger the variation of the plurality of diameters relative to the reference diameter, the larger the value becomes, and the smaller the variation, the smaller the value becomes.

[0098] In such a case, if the value of the first feature quantity is large, it is highly likely that at least one of the following has occurred: the coin is deformed and the center of the detected coin is shifted from the center of the real coin. On the other hand, if the value of the first feature quantity is small, it is highly likely that the coin is not significantly deformed and the center of the detected coin is not significantly shifted from the center of the real coin.

[0099] Furthermore, if the value of the second feature amount is large, there is a high possibility that the coin is significantly deformed. Furthermore, if the value of the second feature amount is small, there is a high possibility that the center of the detected coin is not significantly deviated from the center of the real coin.

[0100] When the coin is deformed, the first feature amount becomes large and the second feature amount also becomes large. If the coin is not deformed but the detected center of the coin is shifted from the true center of the coin, the first feature value tends to be large and the second feature value tends to be small. If the coin is not deformed and the detected center of the coin is not displaced from the true center of the coin, the first feature amount tends to be small and the second feature amount tends to be small. When the third feature is the product of the first feature and the second feature, the value of the third feature tends to be largest when the coin is deformed, next largest when the coin is not deformed but the center of the detected coin is shifted from the center of the true coin, and smallest when the coin is not deformed and the center of the detected coin is not shifted from the center of the true coin.

[0101] Therefore, by using the third feature, it becomes possible to set a threshold between the third feature calculated when the coin is deformed and the third feature calculated when the coin is not deformed but the center of the detected coin is shifted from the center of the true coin, making it possible to determine with greater accuracy whether the coin is deformed or not.

[0102] (Modification 2 of Embodiment 2) Next, a deformed coin determination device according to Modification 2 of Embodiment 2 of the present disclosure will be described. The deformed coin determination device of embodiment 2 differs from the above-mentioned deformed coin determination device 110 in that it is equipped with a diameter calculation means and a reference diameter calculation means in addition to a radius calculation means, a reference radius calculation means, a first feature calculation means, a deformed coin determination means and a second feature calculation means. In addition, in the above-mentioned deformed coin determination device 110, the reference diameter and diameter were calculated using the radius calculated by the radius calculation means, but the deformed coin determination device of variant example 2 of embodiment 2 of the present disclosure differs from the above-mentioned deformed coin determination device 110 in that a separate diameter calculation means and a separate reference diameter calculation means are used to calculate the diameter and the reference diameter separately.

[0103] FIG. 10 is a block diagram illustrating the configuration of a deformed coin determination device according to Modification 2 of Embodiment 2. As shown in FIG. The deformed coin determination device 110b shown in Figure 10 comprises a radius calculation means 111, a reference radius calculation means 112, a first feature calculation means 113, a diameter calculation means 117, a reference diameter calculation means 118, a second feature calculation means 115, and a deformed coin determination means 114. The radius calculation means 111, the reference radius calculation means 112, the first feature calculation means 113, the diameter calculation means 117, the reference diameter calculation means 118, the second feature calculation means 115, and the deformed coin determination means 114 may be incorporated into an electronic computer and function by executing a program in a controller (processor) such as a CPU.

[0104] Next, the operation of the deformed coin detection device according to the first embodiment will be described with reference to FIG. FIG. 11 is a flowchart illustrating an example of the operation of the deformed coin determination device according to the second modification of the second embodiment.

[0105] As shown in FIG. 11, in the deformed coin determination device 110b, first, the radius calculation means 111 calculates a plurality of radii of the coin from an image of the coin (step S31).

[0106] Next, the reference radius calculation means 112 calculates the reference radius of the coin from the image of the coin (step S32).

[0107] Next, the first feature amount calculation means 113 calculates a first feature amount that represents the variation of a plurality of radius data based on a plurality of radii with respect to reference radius data based on a reference radius (step S33).

[0108] Furthermore, as shown in FIG. 11, in the deformed coin determination device 110, the diameter calculation means 117 calculates a plurality of diameters of the coin from the image of the coin (step S34).

[0109] Next, the reference diameter calculation means 118 calculates the reference diameter of the coin from the image of the coin (step S35).

[0110] Next, the second feature amount calculation means 115 calculates a second feature amount that represents the variation of the plurality of diameters relative to the reference diameter (step S36).

[0111] In addition, the deformed coin determination device 110b may perform (Step S34) to (Step S36) in parallel with (Step S31) to (Step S33). In addition, in the deformed coin determination device according to variant 2 of embodiment 2, the order in which each step is performed is not limited as long as the first feature amount and the second feature amount can be calculated before the <deformed coin determination step (step S37)> described below.

[0112] Next, the deformed coin determination means 114 determines whether or not the coin is a deformed coin based on the first characteristic amount and the second characteristic amount (step S37), and the operation of the deformed coin determination device 110b ends.

[0113] Each step will be described in detail below with reference to the drawings. Note that (Step S31) to (Step S33) and (Step S37) are the same as (Step S21) to (Step S23) and (Step S25) in the deformed coin determination device 110, respectively, and therefore a description thereof will be omitted here.

[0114] <Diameter calculation step (process S34)> FIG. 12 is an explanatory diagram schematically illustrating an example of a method in which the radius calculation means calculates a plurality of radii of a coin from an image of the coin in the deformed coin determination device according to Modification 2 of Embodiment 2 of the present disclosure. In the diameter calculation step (step S34), as shown in FIG. 12, points P′ (P1′ to P′) on the outer periphery 22 of the coin are calculated so as to divide the coin 20 into 32 parts, with the center 21 of the coin as the axis. 32 ´) to detect.

[0115] Next, for each point P'(P1'~P 32 '), pairs of points P' are detected where the angle of the line segment connecting each point P' from the center 21 of the coin is 180°, and the distance between the paired points P' (the sum of the two radii calculated from the two paired points P') is calculated as the diameter R' (R1' to R 16 ´) is calculated as follows. In Figure 12, multiple diameters R' are calculated by positioning each point P' for obtaining multiple diameters R' at equal intervals on the outer periphery 22 of the coin, but in the modified coin judgment device disclosed herein, the intervals between each point P' do not have to be equal, and diameter R' can be calculated by positioning each point P' at a predetermined interval on the outer periphery of the coin. In addition, in Figure 12, multiple diameters R' are obtained based on points P' on the outer circumference of the coin, which divides the coin 20 into 32 parts with the coin center 21 as the axis, but in the modified coin judgment device disclosed herein, the number of divisions is not particularly limited as long as two or more diameters R' can be obtained. In addition, in Figure 12, each point P' on the outer periphery 22 of the coin is detected and then the diameter R' is calculated, but in the deformed coin determination device 110b, the diameter R' may also be calculated from the intersection of a straight line passing through the center 21 of the coin and the outer periphery 22 of the coin.

[0116] <Reference diameter calculation step (process S35)> Next, in step S35, the diameters R' calculated in step S34 are sorted in order of length, and the average of the diameters R' of the four central diameters is calculated to obtain the reference diameter R. s ' may be calculated. In the above explanation, the reference diameter R s' was calculated as the average of the diameters R' of the four central lines, but the reference diameter R was calculated by calculating the average of a predetermined number of central lines, for example, the two central lines. s ´, and the average value of all diameters and the reference diameter R s ´ can also be used.

[0117] Also, the diameter R' is the reference diameter R s If the value is larger than ', the value of the diameter R is set to the reference diameter R s It is also possible to perform processing to make it the same value as '.

[0118] <Second feature amount calculation step (step S36)> In step S36, the second feature amount calculation means 115 calculates the reference diameter R s A second feature value representing the variation of the plurality of diameters R' relative to the diameter R' is calculated. The method for calculating the second feature amount may be the same as the method described above (step S24-3).

[0119] (Embodiment 3) Next, a coin validator equipped with the deformed coin determination device of the present disclosure and a coin processing machine equipped with the coin validator will be described. FIG. 13 is a block diagram illustrating the configuration of the coin validator of the present disclosure. The coin validator 201 shown in FIG. 13 includes an imaging unit 231, a storage unit 234, and a control unit 235. In addition, the memory unit 234 stores image information 234a, standard image information 234b, and threshold information 234c, and the control unit 235 further includes an image acquisition unit 235a, a position determination unit 235b, a denomination identification unit 235c, and a deformed coin determination unit 210.

[0120] The coin validator 201 includes the deformed coin determination device according to the first or second embodiment of the present disclosure as the deformed coin determination unit 210.

[0121] The imaging unit 231 includes a light irradiation device that irradiates the coin with one or more light sources of visible light such as green light or infrared light, and a CCD (Charge Coupled Device) camera / CMOS (Complementary Metal Oxide Semiconductor) camera that receives the light irradiated from the light irradiation device and reflected by the coin. The imaging unit 231 then captures an image of the coin and passes the captured image data to the image acquisition unit 235a.

[0122] The storage unit 234 is a storage device such as a RAM (Random Access Memory) or a nonvolatile memory, and stores image information 234a and threshold information 234c. The image information 234a is image data of the coin captured by the imaging unit 231.

[0123] The threshold information 234c is threshold data used when determining whether a coin is a deformed coin. The deformed coin determination unit 210 determines whether a coin is a deformed coin based on whether the calculated feature amount (first feature amount, a combination of the first feature amount and the second feature amount, or the third feature amount) is within the threshold range of the threshold information 234c. Details of the threshold information 234c will now be described with reference to FIG. 14.

[0124] Fig. 14 is a diagram showing an example of threshold information. As shown in Fig. 14, threshold information 234c includes a "denomination" item and a "threshold" item.

[0125] A "threshold" is set for each "denomination," and when comparing the first feature, the combination of the first feature and the second feature, or the third feature with the threshold, the threshold corresponding to the coin denomination is used.

[0126] This allows the coin validator 201 to take into account differences in deformation rates due to the characteristics of each denomination of coins, and to determine with higher accuracy whether or not a coin is a deformed coin. Note that the threshold value information 234c may have only one type of threshold value, rather than for each denomination.

[0127] Returning to the explanation of Fig. 13, the coin identification machine 201 will be further described. The control unit 235 is a control unit that performs overall control of the coin identification machine 201. The image acquisition unit 235a is a processing unit that acquires image data of the coin captured by the imaging unit 231 and transfers the image data to the image information 234a in the storage unit 234.

[0128] The position determining unit 235b is a processing unit that performs processing to determine the center and periphery of the coin from the image information 234a. Specifically, the position determination unit 235b sets a tentative center of the coin shown in the image information 234a, cuts out a partial image including the outer periphery of the coin, and detects the outer periphery. Then, the position determination unit 235b corrects the center position of the coin based on the detected trajectory of the outer periphery of the coin. In this way, the positions of the center and outer periphery of the coin are determined.

[0129] The denomination identification unit 235c is a processing unit that performs processing to identify the denomination and the front and back of the coin based on the center position determined by the position determination unit 235b and the size and pattern of the coin reflected in the image information 234a. The denomination identification unit 235c also performs processing to identify whether the coin is genuine or not by comparing it with standard image information 234b for each denomination pre-stored in the storage unit 234. Note that the denomination identification unit 235c may also identify the denomination based on the weight, thickness, etc. of the coin.

[0130] The deformed coin determination unit 210 determines whether or not the coin is a deformed coin, as explained in the first and second embodiments above.

[0131] Next, a coin processing machine of the present disclosure equipped with the coin validator of the present disclosure will be described. FIG. 15 is a side cross-sectional view that schematically illustrates an example of a coin processing machine according to the present disclosure.

[0132] As shown in Figure 15, the coin processing machine 202 comprises a housing 240 having an approximately rectangular parallelepiped shape, an inlet 241 for inserting coins from the outside of the housing 240 to the inside, and a supply section 242 for supplying coins inserted into the inlet 241 to a coin dispensing unit 244 described later.

[0133] Furthermore, a control unit 260 is provided inside a housing 240 provided in the coin processing machine 202, and controls each component element. The control unit 260 is a part that controls the entire coin handling machine 202 including the coin validator 201 and the like.

[0134] The coin handling machine 202 further includes a coin feeding unit 244 that stores and feeds out coins supplied from the supply unit 242. A transport unit 245 that transports the fed coins inside the housing 240 is connected to the coin feeding unit 244.

[0135] The conveying section 245 is provided with a conveying path 246 that extends in a substantially horizontal direction, and coins dispensed from the coin dispensing unit 244 are conveyed one by one along the conveying path 246. A belt-like coin holding mechanism (not shown) is provided above the conveying path 246 to prevent coins being conveyed on the conveying path 246 from floating.

[0136] Furthermore, a coin validator 201 is provided upstream of the transport unit 245, and when a coin passes through the coin validator 201, an image of the coin is captured by an imaging unit of the coin validator 201. Meanwhile, a sorting unit 247 is provided downstream of the transport unit 245, and coins transported from the transport unit 245 via the transport path 246 are sorted based on the recognition results recognized by the denomination recognition unit 235c, and sent to each of the openings 248a, 248b, 248c, and 248d.

[0137] Specifically, coins that are determined to be deformed coins by the deformed coin determination unit 210 of the coin identification machine 201, coins that cannot be identified by the denomination identification unit 235c, or coins that are identified as not genuine coins are discharged to the reject unit 232 as rejected coins.

[0138] At this time, the rejected coins are discharged to the reject section 232 accessible from outside the housing 240 via a rejected coin opening 248a and a rejected coin chute 251 provided below the sorting section 247.

[0139] Furthermore, the coins are stored in the storage units 233 for each denomination identified by the denomination identification unit 235c through openings 248b, 248c, 248d and a chute 249 provided below the sorting unit 247.

[0140] In the above explanation, coins determined to be deformed coins are discharged to the reject unit 232, but they may not be recycled and may instead be stored in the storage unit 233. Also, a separate storage unit for rejected coins may be provided within the coin processing machine 202, and coins determined to be deformed coins may be sorted and stored in the storage unit for rejected coins.

[0141] In the above explanation, coins are sorted by denomination and stored in the storage unit 233, but multiple denominations may be stored in a mixed state. The coins stored in the storage unit 233 are collected by a bank employee or the like who handles cash collection operations by opening the door 243 of the housing 240.

[0142] In addition, a foreign matter discharge chute 250 is provided below the coin feed unit 244, and foreign matter etc. sent from the coin feed unit 244 to the foreign matter discharge chute 250 is discharged to the reject section 232 via a rejected coin chute 251.

[0143] Here, a temporary storage section (not shown) may be provided between openings 248b, 248c, 248d and storage section 233, and coins stored in the temporary storage section may be stored in storage section 233 at a predetermined time.

[0144] In this way, in the coin processing machine 202, coins inserted into the coin slot 241 are sent to the coin dispensing unit 244, and the coins dispensed from the coin dispensing unit 244 pass through the coin identifier 201 on the conveying path 246 and are then sorted by the sorting section 247.

[0145] Specifically, if the control unit 235 determines that the coin is a deformed coin, it is returned to the reject unit 232 as a rejected coin, and normal coins are stored in the storage unit 233.

[0146] Next, the operation of the coin processing machine of the present disclosure will be described with reference to FIG. FIG. 16 is a flowchart illustrating an example of the operation of the coin processing machine of the present disclosure.

[0147] As shown in FIG. 16, the image acquisition unit 235a acquires an image of the coin captured by the imaging unit 231 (step S101), and transfers it to the image information 234a in the storage unit 234.

[0148] Thereafter, the position determining unit 235b sets a tentative center of the coin based on the image information 234a (step S102), and determines the periphery of the coin based on the tentative center (step S103).

[0149] Then, the position determining unit 235b corrects the position of the center of the coin based on the periphery of the coin determined in (step S103) (step S104), and determines the periphery of the coin again based on the corrected center of the coin (step S105).

[0150] Next, the denomination identifying unit 235c identifies the denomination and the front and back of the coin based on the position of the center of the coin determined in (step S104) and the size and pattern of the coin shown in the image information 234a (step S106).

[0151] Then, the deformed coin determination unit 210 determines whether the coin is a deformed coin based on the center position and outer circumference of the coin determined in (step S104) and (step S105), and the threshold value corresponding to the denomination identified in (step S106) (step S107).

[0152] If the deformed coin determination unit 210 determines that the coin is a deformed coin (Yes in step S108), it ejects the coin to the reject unit 232 (step S109), and the deformed coin determination process executed by the coin handling machine 202 ends.

[0153] On the other hand, if the deformed coin determination unit 210 determines that the coin is not a deformed coin but a normal coin (step S108, No), it stores the coin in the storage unit 233 (step S110) and terminates the deformed coin determination process performed by the coin processing machine 202. [Industrial Applicability]

[0154] As described above, the deformed coin detection device according to the present disclosure is useful for detecting deformed coins with high accuracy. [Explanation of symbols]

[0155] 10, 110, 110a, 110b Deformed coin detection device 11, 111 Radius calculation means 12, 112 Reference radius calculation means 13, 113 First feature calculation means 14, 114 Deformed coin determination means 20 coins 21 Coin Center 22 Coin circumference 115 second feature calculation means 116 Third feature calculation means 117 Diameter calculation means 118 Reference diameter calculation means 201 Coin Identifier 202 Coin Processing Machine 210 Deformed coin detection unit 231 Imaging unit 232 Rejection Department 233 Storage area 234 Storage section 234a Image information 234b Standard Image Information 234c Threshold Information 235 Control Unit 235a Image acquisition unit 235b Positioning section 235c Denomination identification part 240 cabinet 241 Inlet 242 Supply section 243 Door 244 Coin Feeding Unit 245 Transport section 246 Transport Path 247 Sorting Department 248a, 248b, 248c, 248d opening 249 shots 250 Foreign object discharge chute 251 Reject Coin Chute 260 Control Unit

Claims

1. a radius calculation means for calculating a plurality of radii of the coin from an image of the coin; a reference radius calculation means for calculating a reference radius of the coin from the image; a first feature value calculation means for calculating a first feature value representing a variation of a plurality of radius data based on the plurality of radii with respect to reference radius data based on the reference radius; and a deformed coin determination means for determining whether the coin is a deformed coin based on the first feature amount.

2. 2. The deformed coin determination device according to claim 1, wherein the radius calculation means calculates the plurality of radii so that the points for obtaining the plurality of radii are positioned at predetermined intervals on the outer periphery of the coin.

3. A deformed coin determination device as described in claim 1 or 2, wherein the variation of the multiple radius data relative to the reference radius data is the variation of the difference between the reference radius data and the multiple radius data, or the variation of the ratio of the multiple radius data to the reference radius data.

4. The deformed coin determination device according to claim 1 or 2, wherein the first feature amount is a value calculated by the following formula (1): [Equation 1]

5. The first feature amount calculation means The plurality of radii are grouped into groups of p adjacent radii (where p is a natural number of 2 or more), calculating a sum based on p radii for each set as the plurality of radius data; The deformed coin determination device according to claim 1 or 2, wherein the first feature amount is calculated based on the summed value.

6. The deformed coin determination device described in claim 5, wherein the first feature calculation means calculates, as the reference radius data, the product of the number of radii used to calculate the total value and the reference radius for each group.

7. The deformed coin determination device further includes a second feature value calculation means for calculating a second feature value representing a variation of a plurality of diameters calculated from the image relative to a reference diameter calculated from the image, The deformed coin determination device according to claim 1 or 2, wherein the deformed coin determination means determines whether the coin is a deformed coin based on the first characteristic amount and the second characteristic amount.

8. The deformed coin determination device according to claim 7 , wherein the variation of the plurality of diameters relative to the reference diameter is the variation of the difference between the reference diameter and the plurality of diameters, or the variation of the ratio of the plurality of diameters to the reference diameter.

9. The deformed coin determination device according to claim 7 , wherein the second feature amount is a value calculated by the following formula (2): [Equation 2]

10. further comprising a third feature amount calculation means for calculating a third feature amount based on the first feature amount and the second feature amount; The deformed coin determination device according to claim 7 , wherein the deformed coin determination means determines whether the coin is a deformed coin based on the third feature amount.

11. The deformed coin determination device according to claim 10 , wherein the third feature amount is a product of the first feature amount and the second feature amount.

12. A coin discriminator comprising the deformed coin determination device according to claim 1 or 2.

13. A coin processing machine comprising the coin validator according to claim 12.

14. A processor comprising: a radius calculation step of calculating a plurality of radii of the coin from an image of the coin; a reference radius calculation step of calculating a reference radius of the coin from the image; a first feature value calculation step of calculating a first feature value representing a variation of a plurality of radius data based on the plurality of radii with respect to reference radius data based on the reference radius; a deformed coin determination step of determining whether the coin is a deformed coin based on the first feature amount.

Images