JP2001299288A - Method and apparatus for detecting foreign matter in dried laver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for detecting foreign matter in dried laver, capable of precisely detecting not only the foreign mater on the surface of the dried laver but also in the inner, and having sufficient accuracy for practical selecting of nondefective articles. SOLUTION: This apparatus for detecting the foreign matter in the dried laver ahs a belt conveyor 2, a feed bed plate 3, and feed rollers 4 and 4a. An infrared irradiating device 5, a diffuser 50 and a CCD area camera 6 are installed between the feed roller 4 and the belt conveyor 2. A distinguishing device for distinguishing the presence or absence of the foreign matter by image- processing the data of a taken picture, and various kinds of controllers for controlling the movement of a separating device 7 are housed in a control box 60. A photoelectric switch 61 is installed in the front side of the infrared irradiating device 5. The separating device 7 is installed in the rear part of the feed roller 4a, and a recovering container 8 for recovering the excluded dried laver N is arranged at the lower part thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method and an apparatus for detecting foreign matter in dried nori. More specifically, the present invention relates to a device that can reliably detect not only the surface of dried laver but also foreign substances such as metal particles that enter the inside and do not emerge from the surface.

[0002]

2. Description of the Related Art Various foreign matters are mixed in paper leaf-shaped dried laver during the operation of collecting nori algae at a cultivation farm and in the processing step using a dried laver manufacturing apparatus. In the work of collecting seaweed progenitors, straw and the like floating on the sea surface are likely to be mixed. Further, in the processing step, metal particles (or powder) such as rust that has peeled off from the movable parts of the machine are likely to be mixed. Most of the straw and the like mixed in the sampling operation are removed in a washing process or the like, but it is difficult to remove metal particles mixed in a final processing stage.

[0003] Therefore, an apparatus capable of detecting a foreign substance mixed in dried laver has been conventionally proposed. As an example, an apparatus that detects foreign matter adhering or mixed in paper-leaved dried laver, and sorts a product having no foreign material as a non-defective product and selecting a mixed product as a defective product (Japanese Unexamined Patent Application Publication No.
253142). In this apparatus, light is applied to the surface of dried nori being fed by a conveyor, the reflected light is imaged by a camera, and a change in the reflected light is analyzed to detect a foreign substance.

[0004]

However, the foreign matter detection device for dried seaweed described in the above publication has the following problems. In other words, although it is necessary to analyze the reflected light reflected on the surface of the dried seaweed, it is difficult to accurately analyze the vague change in the reflected light due to the inclusion of fine foreign substances, and to set the discrimination reference value. It is not easy because the quality (color, gloss, etc.) of nori varies.

Further, the determination as to whether or not a foreign substance has entered is made using reflected light, and it is necessary to irradiate light on both the front and back sides and image the reflected light on both sides. But,
In the first place, the configuration of this device is not functionally sufficient because foreign substances that enter the inside of the dried nori and do not appear on the surface cannot be detected. Therefore, sufficient accuracy cannot be expected in detecting non-contaminated foreign matter in dried nori and selecting non-defective and non-defective products, which is not practical.

(Object of the present invention) The present invention solves the above-mentioned problems. In detecting foreign matter in dried laver, the present invention is not limited to the surface of dried laver and does not enter the surface of the dried laver and does not emerge from the surface. It is an object of the present invention to provide a method and an apparatus for detecting foreign matter of dried laver, which are capable of reliably detecting foreign matter, and which are excellent in practicability to obtain sufficient accuracy in selecting good and defective products. I do.

[0007]

Means of the present invention taken to achieve the above object are as follows. According to the first invention, there is provided a method for detecting foreign matter of dried paper laver, which includes irradiating infrared light from one side of the dried seaweed and imaging the dried seaweed from the other side by a CCD area camera.
Image data is binarized by image processing, and the presence / absence of a foreign substance is determined by detecting a signal representing a foreign substance that does not transmit infrared light, from among the grayscale signals obtained by the binarization, thereby detecting foreign substance in dried laver. Is the way.

According to a second aspect of the present invention, there is provided an apparatus for detecting foreign matter of dried paper laver, comprising an infrared irradiation means for irradiating infrared light from one side of the dried seaweed, and an infrared irradiation means for irradiating the other side of the dried seaweed. A CCD area camera for picking up dried laver and image processing of image data from the CCD area camera to binarize the signal; and detecting a signal representing a foreign substance through which infrared light is not transmitted among the grayscale signals obtained by the binarization. And a determining means for determining the presence / absence of a foreign substance using the method.

According to a third aspect of the present invention, there is provided a paper leaf-shaped dried laver foreign matter detecting device, comprising: a conveyor for transporting the dried laver; a sensor for detecting that the dried laver is at a determination position; Infrared irradiation means for irradiating the dried laver with infrared light from one side, a CCD area camera arranged on the other side of the dried laver for imaging the dried laver, and image processing of the image data obtained by the CCD area camera. Binarization, of the grayscale signal by the binarization, by detecting a signal representing a foreign substance through which infrared light does not pass, by determining means for determining the presence or absence of a foreign substance, characterized by comprising
It is a foreign matter detection device for dried seaweed.

A fourth invention is characterized in that the dried seaweed containing no foreign matter is regarded as a good product and the dried seaweed containing the foreign matter is selected as a defective product. A foreign matter detection device for dried laver according to the second or third invention.

According to a fifth aspect of the present invention, the infrared irradiating means includes a required number of LEDs and means for diffusing and uniformizing the light of the LEDs.
Or a foreign matter detection device for dried laver according to a fourth invention.

An object to be discriminated as a foreign substance is a substance that does not transmit or substantially does not transmit infrared light. For example, various metals or stones such as iron, copper and aluminum,
Sand, mud, shells, etc.

[0013] The wavelength of the infrared light emitted from the infrared irradiating means is a wavelength that can transmit the dried seaweed cells most efficiently.
That is, it is set to 870 to 950 nm, preferably 920 nm, but is not limited to this.

The CCD area camera is of a digital type, and captures an image as a plane unlike a CCD image sensor which scans an image and captures it as an aggregate of lines.
Processing can be performed on still images. Therefore, there is an advantage that the accuracy is higher than the CCD image sensor and the cost is lower. The term “CCD” used in the present invention is an abbreviation for “charge coupled device”. Similarly, the term “LED” is used for “light emitting dio”
de ".

(Operation) The foreign matter detection device for dried laver according to the present invention operates as follows. First, dry nori is transported by a conveyor. The infrared irradiation means irradiates infrared light toward the upper determination position. When the sensor detects that the dried laver is at the determination position, the CCD area camera captures an image of a specific area of the dried laver. C
According to the CD area camera, an image can be taken regardless of whether the dried laver is moving or stopped.

The image data picked up by the CCD area camera is converted into an electric signal, which is converted into a dark signal (dark signal) and a light signal (bright signal) of 256 steps, for example, 256 gradations for each pixel. Further, these signals are binarized with a predetermined level as a boundary, and are converted into two kinds of signals, "1" (dark signal) and "0" (light signal). Then, for example, a portion where each pixel becomes “1” (dark signal) is detected as a foreign substance.

The dried nori containing no foreign matter is conveyed as a good product to the next step such as a packaging step by a conveyor. In addition, the dried seaweed mixed with the foreign matter is removed as a defective product by the sorting means. In addition, the reference value of the size and the number of foreign substances, which is a reference for selection, is appropriately set.

As described above, according to the apparatus for detecting foreign matter of dried laver according to the present invention, image data is binarized by image processing, and a signal representing a foreign substance that does not transmit infrared light among gray-scale signals obtained by the binarization. Since the presence / absence of a foreign substance is determined by the detection, it is possible to reliably detect not only the surface of the dried laver but also the foreign substance that enters the inside and does not come out of the surface. As a result, it is possible to select good and defective dry laver products with sufficient accuracy, which is excellent in practicality.

When the infrared irradiating means includes a required number of LEDs and means for diffusing and uniformizing the light of the LEDs, the image data obtained when the image is picked up includes the signal of the light source caused by the unevenness of the infrared light amount of the light source. Since no unevenness occurs, the accuracy of determining the presence or absence of a foreign substance is improved.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail with reference to the embodiments shown in the drawings. FIG. 1 is a schematic front view showing an embodiment of a foreign matter detection device for detecting foreign matter mixed in dried laver according to the present invention, and FIG. 2 is an operation block diagram showing a control system of the foreign matter detection device shown in FIG. .

Reference numeral A denotes a foreign substance detection device for dried laver, which has a frame 1. A caster 10 is provided at a lower portion of the frame 1. A belt conveyor 2 provided on the right side in FIG. 1 and a feed board plate 3 provided on the left side of the belt conveyor 2 at a required interval are provided on an upper portion of the frame 1.
And two sets of feed rollers 4 and 4a arranged at the front and rear portions of the feed base plate 3. The belt conveyor 2, the feed base plate 3, and the feed rollers 4, 4a constitute a transport line together with a belt conveyor 9 described later.

The feed rollers 4 and 4a are constituted by a lower drive roller 40 and an upper driven roller 41, respectively. The driving roller 40 and the driven roller 41 are both made of rubber. The upper driven roller 41 is placed on the drive roller 40 by using its own weight, and the outer peripheral surfaces thereof are in contact with each other. The driven roller 41 can be urged toward the driving roller 40 by a spring or the like, and the outer peripheral surface thereof is brought close to the driving roller 40 without damaging the dried seaweed N and not disturbing the conveyance. You can also. The heights of the upper surfaces of the belt conveyor 2, the feed plate 3 and the lower drive roller 40 are set to the same height. The belt conveyor 2 and the drive roller 40 are linked by a drive mechanism (not shown), and the feed speed is set to be the same.

Between the belt conveyor 2 and the feed roller 4, there is provided an infrared irradiator 5 and a diffusion plate 50 for diffusing and uniformizing the LED light of the infrared irradiator 5;
A D area camera 6 is provided. The infrared irradiation device 5
The irradiation direction is upward, and it is provided below the height of the upper surface of the belt conveyor 2, that is, the height at which the dried seaweed N is sent. The infrared irradiation device 5 is an LED that emits infrared light.
Are arranged as closely arranged vertically and horizontally to form a light source. Note that a light-emitting body other than the LED may be used as the light source.

The diffusion plate 50 is located above the infrared irradiation device 5 and below the height of the upper surface of the belt conveyor 2. The diffusion plate 50 is a milky white plastic plate,
Two sheets are provided above and below at required intervals. Note that the diffusion plate 50 may be a single sheet as long as the infrared light diffusion function is sufficient,
The number is not particularly limited. The material is not particularly limited as long as there is no functional problem.

The CCD area camera 6 is fixed to the control box 60 at a position higher than the height of the upper surface of the belt conveyor 2 with the image pickup direction downward. In the present embodiment, the CCD area camera 6 is a MC-SW201 (pixel number, 250,000 pixels: 510 bit × 492 bi) manufactured by Taiyo Elex Corporation.
t), but is not limited to this. In addition,
The two CCD area cameras 6 are arranged side by side in the width direction of the belt conveyor 2 (the depth direction in FIG. 1). The number of CCD area cameras 6 is not particularly limited. By using a plurality of CCD area cameras 6, the resolution per unit area at the time of imaging can be improved, and foreign substances can be more accurately determined.

The control box 60 is provided with a discriminating device for discriminating the presence or absence of foreign matter by performing image processing on image data obtained by the CCD area camera 6, the belt conveyor 2, the feed rollers 4, 4a.
And various control devices for controlling the operation of the sorting device 7 described later. In addition, C
A cover 61 covering the periphery of the CD area camera 6 is provided. On the front side of the infrared irradiation device 5, a photoelectric switch 6 serving as a sensor for detecting that the dried laver N is at the determination position.
2 is provided with the detection direction upward. Photoelectric switch 62
Is a reflection type, and detects dry laver N passing above. If there is no functional problem, another sensor can be used instead of the photoelectric switch 62.

Behind the feed roller 4a, a sorting device 7 is provided at the same height as the upper surfaces of the belt conveyor 2 and the feed base plate 3. The sorting device 7 has a structure in which the guide plate 70 is rotated within a required angle range by a rotary solenoid (not shown). In the present embodiment, the upper surface of the guide plate 70 is rotated upward from a horizontal state within a required angle (for example, 30 °).

Below the sorting device 7, a collecting container 8 for collecting dried nori removed from the transport line is disposed. The collection container 8 is attached to the rear part of the frame 1. In addition, a belt conveyor 9 for sending dried laver N determined as a non-defective product with no foreign matter mixed therein to the next process such as a packaging process is disposed behind the sorting device 7. Also,
An image of the dried seaweed N that has been subjected to image processing can be viewed on a monitor (not shown).

(Operation) With reference to FIGS. 1 and 2, the operation of the foreign matter detecting device A for dried laver according to the present invention will be described.
First, the CCD area camera 6 is set. That is,
Setting of imaging area, setting of quality criteria for foreign matter,
The quality standard and the sensitivity of the foreign matter are set.

(1) Main power supply is turned on. (2) The power of the infrared irradiation device 5 is turned on. → LED lights. The power of the CCD area camera 6 is turned on. → photoelectric switch 62
Actuation. Power ON the belt conveyors 2 and 9. → The belt conveyors 2, 9 and the feed rollers 4, 4a are operated. The switch of the sorting device 7 is turned on.

(3) Paper leaf-shaped dried laver N is sequentially placed on the belt conveyor 2 and sent. Dried seaweed N is in the imaging area (CC
It is sent in the direction between the D area camera 6 and the infrared irradiation device 5). Infrared rays are emitted upward from the lower infrared ray irradiating device 5. The infrared rays from the LED are diffused by the diffusion plate 50 and are almost uniform. The infrared rays pass through the lens of the CCD area camera 6 and enter the imaging device.

(4) When the tip of the dried seaweed N is detected by the photoelectric switch 62, the CCD area camera 6 releases the electronic shutter (for example, shutter speed: 1/200).
(0 second, 60 times / second), an image of a specific area of the dried seaweed N moving on the transport line is taken. Then, each image data is captured as a digital signal of 250,000 pixels as a still image.
In addition, according to the CCD area camera 6, it is possible to take an image even when the dried seaweed is moving or stopped.
It is not usually affected by movement speed.

(5) The image data picked up by the CCD area camera 6 is converted into an electric signal, which is converted into a dark signal (dark signal) and a light signal (bright signal) of 256 steps, for example, 256 steps for each pixel. You. Further, these signals are binarized with a predetermined level as a boundary, and are "1" (dark signal) and "0".
(Light signal). Then, a portion where each pixel becomes "1" (dark signal) is detected as a foreign substance. On the monitor, a portion of the nori that transmits infrared light (a portion that becomes a light signal) moves brightly, and a portion of a foreign substance that does not transmit infrared light (a portion that becomes a dark signal) moves darkly.

(6) If it is determined that foreign matter is mixed in the dried laver N, a defective signal is sent to the sorting device 7. When a defective signal is sent, the dried laver N
Is detected, the guide plate 7 of the sorting device 7 is detected.
0 rotates upward and guides the dried laver N to the lower collecting container 8 and removes it from the transport line. At this time, dried seaweed N
Is reliably pushed and fed by the front and rear feed rollers 4 and 4a, so that the guide to the collection container 8 is reliably performed. When no foreign matter is mixed in the dried laver N and no defect signal is sent, the guide plate 70 of the sorting device 7 does not operate, the dried laver N is sent to the belt conveyor 9, and the packaging process is performed. To the next step.

It should be noted that the terms and expressions used in the present specification are merely illustrative and not restrictive, and do not exclude terms and expressions equivalent to the above-mentioned terms and expressions. Further, the present invention is not limited to the illustrated embodiment, and various modifications can be made within the scope of the technical idea.

[0036]

The present invention has the above configuration and has the following effects. (A) According to the foreign matter detection device for dried laver according to the present invention,
The image data is binarized by image processing, and among the grayscale signals obtained by the binarization, the presence or absence of a foreign substance is determined based on a signal representing a portion that does not transmit infrared light. Even foreign substances that have not come out can be reliably detected. As a result, it is possible to select good and defective dry laver products with sufficient accuracy, which is excellent in practicality.

(B) The infrared irradiation means is a required number of LEDs
And a means for diffusing and uniformizing the light of the LED does not cause unevenness in the signal due to unevenness in the amount of infrared light of the light source in the image data at the time of imaging. The accuracy is improved.

[Brief description of the drawings]

FIG. 1 is a schematic front view showing an embodiment of a foreign matter detection device for dried laver according to the present invention.

FIG. 2 is an operation block diagram showing a control system of the foreign matter detection device for dried nori shown in FIG. 1;

[Explanation of symbols]

 A foreign matter detection device for dried seaweed 1 frame 10 caster 2 belt conveyor 3 feed base plate 4, 4a feed roller 40 drive roller 41 driven roller 5 infrared irradiation device 50 diffusion plate 6 CCD area camera 60 control box 61 cover 62 photoelectric switch 7 sorting Device 70 Guide plate 8 Collection container 9 Belt conveyor N Dried seaweed

Claims (5)

[Claims] 1. A method for detecting foreign matter of paper laver dried laver, comprising: irradiating infrared light from one side of the dried laver, imaging the dried laver from the other side by a CCD area camera, and imaging the captured data. A method for detecting foreign matter in dried laver, characterized by processing and binarizing the signal to detect presence or absence of a foreign matter by detecting a signal representing a foreign matter that does not transmit infrared light, from among the grayscale signals obtained by the binarization. 2. An apparatus for detecting foreign matter of paper laver dried laver, comprising: an infrared irradiator for irradiating infrared light from one side of the dried laver; and an infrared detector disposed on the other side of the dried laver to image the dried laver. C
Discriminating the presence / absence of foreign matter by detecting a signal representing a foreign matter that does not transmit infrared light, by binarizing the image data obtained by the CD area camera and the CCD area camera by image processing, and detecting a signal representing a foreign matter that does not transmit infrared light among the grayscale signals obtained by the binarization And a means for detecting foreign matter in dried laver. 3. A foreign matter detection device for a paper leaf-shaped dried laver, comprising: a conveyor for transporting the dried laver; a sensor for detecting that the dried laver is located at a discrimination position; An infrared irradiating means for irradiating infrared light from the side, and a C arranged on the other surface side of the dried laver for imaging the dried laver
Discriminating the presence / absence of foreign matter by detecting a signal representing a foreign matter that does not transmit infrared light, by binarizing the image data obtained by the CD area camera and the CCD area camera by image processing, and detecting a signal representing a foreign matter that does not transmit infrared light among the grayscale signals obtained by the binarization And a means for detecting foreign matter in dried laver. 4. The drying method according to claim 2, further comprising means for selecting dried laver containing no foreign matter as a good product and selecting dried laver containing foreign matter as a defective product. Nori foreign matter detection device. 5. The infrared irradiation means includes a required number of LEDs,
The apparatus for detecting foreign matter of dried laver according to claim 2, further comprising means for diffusing and uniformizing the light of the LED.