KR100948795B1 - Apparatus for detecting faulty coins - Google Patents

Abstract

PURPOSE: An apparatus for detecting faulty coins is provided to improved reliability of a test for faulty coin by obtaining an image photographed three times continuously. CONSTITUTION: A coin supplying unit(70) supplies a coin(40) to inspect a faulty coin. A feeding unit(60) transfers the supplied coin. A sensor(50) senses the existence of the coin. A camera(10) photographs the coin. A controller(100) controls for 3 time continuous image capturing of the same coin transferred from the transfer apparatus.

Description

Coin Inspector {Apparatus for Detecting faulty Coins}

The present invention relates to a coin inspection device, and in more detail, if there are minute scratches on the base surface of the coin to be inspected, the same coin may be solved to solve a problem that it is very difficult to identify the minute scratches only by the image photographed from the front of the camera. The present invention relates to a coin inspection device which improves such a problem by taking an image of a coin that is slightly squeezed from side to side in front of the coin, which is a portion of the camera lens.

Generally, coins are manufactured by stamping various patterns suitable for each coin value. Coins made in this way must pass a rigorous inspection process before they can be used as real currency. These tests included circular deficiency, one-sided indentation, vanta (slightly indented in some glyphs), glyph inconsistency, glyph misalignment, glyphs compared to positive

The process involves screening coins that are judged to be defective, scratched, discolored, stained, or polished.

Since these inspections were mainly performed by hand, it was inefficient in terms of time and labor costs, and it was difficult to keep up with the quantity of coins produced by high-speed stampers. Therefore, a high-speed precision inspection apparatus was required to replace manual labor.

On the other hand, in order to prevent malfunction of the machine due to defective coins and to prevent business loss, coin inspection devices are also required in vending machines and coin exchangers, and such devices are already known. Such conventional coin inspection apparatuses are largely classified into mechanical and electronic systems. In general, a conventional mechanical coin inspection device selects coins by standard through a plurality of frames corresponding to the diameter of each coin. The coins thus classified may be finally selected again through an identification plate for unevenness inspection. However, such a mechanical coin inspection device has a disadvantage that it is difficult to accurately pick out defective coins of similar material.

The electronic coin test apparatus developed to overcome the above-mentioned drawbacks of the mechanical coin test device arranges coils in the moving passages of the coin. Current flows through the excreted coil, so that when the positive passes, a certain magnitude of output frequency can be obtained. However, when the defective coins having different metal contents pass, different output frequencies appear, so that the defective coins can be determined using the frequency difference.

Such an electronic coin tester can accurately determine the material of a coin compared to a mechanical coin tester, but the pattern of the coin cannot be accurately identified. The conventional coin inspection apparatus as described above basically checks the size and material of the coin to determine whether there is a defect. Therefore, since it is used to sort out heterogeneous coins of different sizes and materials, in order to determine whether or not a coin of the same size and material is manufactured, a more precise inspection equipment capable of identifying the pattern of the coins is required.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and while improving the time and cost-effectiveness, the coin inspection apparatus that improves the reliability of the inspection of defective coins by obtaining three consecutive images of the same coin The purpose is to provide.

In order to achieve the above object, the coin inspection device according to the present invention, the coin supply unit 70 for supplying the coin 40 to inspect the bad coin, the conveying device 60 for conveying the supplied coin 40 ), A time delay set by receiving a sensor 50 for detecting the presence of the coin, a camera 10 for photographing the coin 40, and a signal for detecting the coin 40 from the sensor 50. And a control device 100 for continuously transmitting three photographing signals to the camera 10 so that the camera 10 photographs the coin 40 continuously.

The camera is characterized in that the area camera 10,

The lighting device includes a lighting device 20 that provides a constant lighting for photographing the coins 40, and a dome lighting device 30 which is an illuminator having a dome shape corresponding to one half of an egg shell. With

The controller 100 is characterized in that the photographed images of the standardized coin is stored in advance, the controller 100 is characterized in that the photographed image of the standardized coin according to the angle is stored in advance,

The control device 100 is characterized in that the photographed image of the coin is normalized in real time according to the extreme wear.

Coin inspection apparatus according to the present invention has the following excellent effects.

1. Lighting

Conventional coin inspection device relies only on the dome lighting to photograph the coin, but the present invention improves the quality of the coin inspection by using the dome lighting device and the lighting device.

2. Camera

In the conventional method of inspecting a bad coin by using a black and white line scan camera, since the moving speed of the conveyor belt for transporting the coin is not constant, the coin was often photographed in a distorted state. Therefore, there was a problem that the reliability of the coin test fell considerably. However, the coin inspection apparatus according to the present invention improves the reliability of coin inspection by using the area color camera 10 to obtain an accurate image at the time of photographing the coin even if the speed of the conveyor belt conveying the coin is fluid. .

3. Acquiring three consecutive shots by the camera for the same coin

If there are minute scratches on the base of the coin to be examined, it is very difficult to identify the minute scratches only with the image taken from the front of the camera. Therefore, in the present invention, the problem is solved by taking an image of a coin which is slightly rubbed left and right from the front of the coin with respect to the same coin.

4. Real time model update

A basic inspection method for inspecting defective coins using the coin inspection apparatus according to the present invention is to determine whether or not defective by examining a matching rate using a gold model. However, having only one model does not cope with the change of coins caused by extreme wear over time. Therefore, in order to perform accurate inspection without increasing the defective rate even in this polished die wear, a system was applied to the gold model in real time during the inspection.

5. Differential gold model by angle.

Coins don't have a constant angle and the image comes in differently depending on the angle. In particular, the image taken from different angles for the embossed portion of the coin is also different from the image taken due to the difference in shadow due to lighting.

In the present invention, in order to reduce the degradation of the reliability of the inspection due to the difference of the shadow, the inspection is performed by differentializing 36 gold models for each angle.

Advantages, features and preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings.

1 is an overall configuration diagram schematically showing each component of the coin test apparatus according to the present invention.

Referring to Figure 1, the coin inspection apparatus according to the present invention is a coin supply unit 70 for supplying the coin 40 to inspect the bad coin, the conveying device 60 for conveying the supplied coin 40, the coin The sensor 50 for detecting presence, the area camera 10 for photographing the coins 40, the illumination device 20 for providing constant illumination for photographing the coins 40, and half of the egg shells. Dome illumination device 30, which is an illuminator having a corresponding dome shape, and a signal that detects the coin 40 from the sensor 50 are received and three consecutive times for the same coin 40 after a predetermined time delay. And a control device 100 which transmits a photographing signal to the area camera 10 so that the area camera 10 photographs the coins 40 in succession.

The constant illumination provided by the illumination device 20 according to the present invention is a method of shooting light toward the coin 40, which is a pass-through body, and the light reflected from the coin 40, which is a subject, to face the area camera 10. A term commonly used in the field of vision for taking a picture of a subject with illumination.

In the dome lighting device 30 according to the present invention, the lights are installed along the inner part of the bottom rounded edge of the dome-shaped cover which is empty inside, and the lights radiate toward the entire dome surface of the inside and the emitted light is domed. It is a lighting device that reflects each other inside to provide light to the coin 40 that is the subject.

The conveying apparatus 60 according to the present invention may be composed of a motor and a conveyor belt driven by the motor.

FIG. 2 shows that the camera of the coin inspection apparatus according to the present invention takes three consecutive shots for one coin at a predetermined time interval. 3A to 3C show exemplary photographs in which three consecutive shots have been taken for one coin at regular time intervals by the camera of the coin inspection apparatus according to the present invention.

Referring to FIG. 2, the coin checker according to the present invention is configured to supply a coin 40 from the coin supply unit 70 to the conveying device 60, and detect the coin 40 conveyed by the conveying device 60. ) Detects and sends a coin detection signal to the trigger board of the control device 100, the trigger board puts a delay of a certain time in the coin detection signal to record three consecutive shooting signals. To the area camera (10).

The photographing signal of the present invention is received by the area camera 10, three consecutive shots are taken for the same coin 40, and the three images shot for the same coin 40 are transmitted to the controller 100. do. FIG. 3 shows exemplary photographs in which three consecutive shots have been taken for one coin 40 at a constant time interval by the area camera 10 of the coin inspection device according to the present invention.

When there are minute scratches on the base surface of the coin 40 to be inspected according to the present invention, it is very difficult to identify the minute scratches only by the image photographed from the front of the lens of the area camera 10. Therefore, in the present invention, in order to obtain an image by photographing the same coin 40 with the area camera 10, this problem is solved by taking an image of a coin at a position slightly rubbed left and right from the front of the lens of the area camera 10. It was.

In the coin inspection apparatus according to the present invention, in order to solve the above problem, in order to obtain a photographic image corresponding to the center of the lens of the area camera 10, a photograph image slightly projected to the center of right and left slightly for one coin 40. , Three consecutive photographings are performed, and three coincidence images of one coin 40 are inspected for defects.

In the control apparatus 100 according to the present invention, the standard images of the normal coins 40 photographed at various angles and various lighting environments are stored in advance, and the standard images are compared with the images photographed and transmitted by the area camera 10. If not, it is determined whether the coin 40 is defective in a manner that is determined as a defective coin.

In the defective coin test according to the present invention, five kinds of inspections of a pattern, a circle, a center, a color, and a vacancy of the coin 40 are performed to determine whether there is a defect.

4 is a flowchart illustrating a process of detecting whether a coin is defective by the coin inspection device according to the present invention.

Referring to Figure 4, the process of detecting whether or not the coin according to the present invention,

First step 100: supply the coins 40 to be examined to the transfer device 60 through the coin supply unit 70 according to the present invention,

Step 2 120: When the coin 40 conveyed by the feeder 60 approaches the sensor 50, the sensor 50 detects the presence of the coin 40, and the detected signal is controlled by the controller 100. ) Is sent.

Step 3 130: Coin in consideration of the speed at which the coin 40 is conveyed by the conveying device 60, the distance of the point indicated by the lens of the sensor 50 and the area camera 10 in the conveying device 60, etc. Is detected by the sensor 50, the delay time corresponding to the time of facing the lens of the area camera 10 is set, and three consecutive shots are taken for the same coin 40 in accordance with the delay time.

Step 4 140: The three images photographed for the same coin 40 are transmitted to the controller 100 and compared with the images of the standard coins corresponding to the acceptance criteria previously stored in the controller 100. do.

A basic discrimination method for determining a defective coin in the control device 100 according to the present invention is to determine the image of the standard coin corresponding to the acceptance criteria as a gold model, the matching ratio between the three images actually taken and the images of the gold model Investigate (Matching Rate) to determine whether it is defective.

In the present invention, in order to solve the problem of failing to cope with the change of coin due to extreme wear with time if only one model is used, the real time even during inspection to perform accurate inspection without increasing the defective rate even in this polished die wear. The extreme wear was applied to the gold model.

In addition, the coin 40 is not constant angle coming into the transfer device 60, the image is taken differently depending on the angle to be placed. For example, an embossed person in a 500-won coin may be placed upright, or may be turned upside down by 180 degrees, and may be fed to the conveying device 60 at different angles.

Therefore, the same coin 40 can be photographed at different angles, and the same coin 40 is photographed at different angles, the difference in the shadow of the embossed portion appears. In order to reduce the deterioration of inspection reliability due to this shadow difference, the inspection is performed using gold models of standard images photographed at 36 angles to the standard coin.

Step 5 150: The three images photographed for the same coin 40 are classified as defective coins when the controller 100 does not meet the set matching rate by comparing the images of the standard coins.

5A to 5D show exemplary pictures illustrating that there is a difference in the photographed image when photographing at different angles for the same coin.

Referring to FIG. 5, the angle of the coin 40 that is placed on the transfer device 60 is not constant, and the angle photographed by the area camera 10 varies according to the angle that is placed on the transfer device 60. In particular, the image of the embossed portion of the coin is slightly differently shadowed by the influence of lighting according to different angles.

In FIG. 5, each photographed image has a shape in which the same 100 won coin 40 is entered at different angles, and the difference in the image of the shade of the shade of the head of the embossed person is wearing it on the head. As such, a difference occurs in an image photographed with a difference in angle with respect to the same coin 40 due to the difference in the shadow of the lampshade, so that the reliability of the process of inspecting the bad coin may occur.

In order to alleviate this problem, a standardized gold model of photographed images taken at 36 different angles for the same coin corresponding to the standard model is compared with the image of the coin actually photographed during the inspection process.

Although preferred embodiments of the present invention have been described and illustrated using specific terms above, such terms are only for explaining the present invention, and various modifications of the present invention may be made by those skilled in the art without departing from the technical spirit of the present invention. It is obvious that it could be implemented.

Such modified embodiments should not be understood individually from the spirit and scope of the invention, but should fall within the claims appended to the invention.

1 is an overall configuration diagram schematically showing each component of the coin test apparatus according to the present invention.

FIG. 2 shows that the camera of the coin inspection apparatus according to the present invention takes three consecutive shots for one coin at a predetermined time interval.

3A to 3C show exemplary photographs in which three consecutive shots have been taken for one coin at regular time intervals by the camera of the coin inspection apparatus according to the present invention.

4 is a flowchart illustrating a process of detecting whether a coin is defective by the coin inspection device according to the present invention.

5A to 5D show exemplary pictures illustrating that there is a difference in the photographed image when photographing at different angles for the same coin.

** Explanation of symbols for main parts of drawings **

10: area camera 20: constant lighting device

30: dome lighting device 40: coin

50: sensor 60: feeder

70: coin supply unit 100: control device

Claims (6)

Coin supply unit 70 for supplying the coin 40 to inspect the bad coin, A transfer device 60 for transferring the supplied coins 40, A sensor 50 for detecting the presence of the coin 40, A camera 10 for photographing the coin 40, While the coin 40 is being transported by the transfer device 60, the sensor 50 detects the single coin 40 and receives a signal that detects the single coin 40. After the set time delay, the three consecutive photographing signals for the same coin 40 are transmitted to the camera 10 so that the camera 10 conveys the conveying device 60. Coin inspection apparatus, characterized in that it comprises a control device (100) for photographing the same one coin 40 in succession three times. The method of claim 1, Coin inspection apparatus, characterized in that the camera is an area camera (10). The method of claim 1, The coin inspection device further comprises a lighting device, The lighting device includes a dome lighting device 30 which is a lighting device having a dome shape corresponding to one half of the egg shell and the lighting device 20 for providing a constant lighting to photograph the coin 40 A coin inspection device characterized in that. The method of claim 1, The control device 100 is a coin inspection device, characterized in that pre-stored photographed images of the standardized coin. The method of claim 1, The control device 100, the coin inspection device, characterized in that the pre-stored photographed images of the coin according to the angle. delete

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